[libpng17] Imported from libpng-1.7.0alpha10.tar

on SUN OS cc 5.9, which demonstrates the tokenization problem previously
avoided by using /lib/cpp.  Since all .dfn output is now protected
in double quotes unless it is to be macro substituted the fix should work
everywhere.

ANNOUNCE

@@ -1,5 +1,5 @@
 
-Libpng 1.2.10rc1 - April 19, 2006
+Libpng 1.7.0alpha10 - February 7, 2013
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -9,68 +9,141 @@ Files available for download:
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script
 
-   1.2.10rc1.tar.gz
-   1.2.10rc1.tar.bz2
-
-Source files with LF line endings (for Unix/Linux) without the
-"configure" script
-
-   1.2.10rc1-no-config.tar.gz
-   1.2.10rc1-no-config.tar.bz2
+   1.7.0alpha10.tar.xz (LZMA-compressed, recommended)
+   1.7.0alpha10.tar.gz
 
 Source files with CRLF line endings (for Windows), without the
 "configure" script
 
-   lp1210r01.zip
-   lp1210r01.tar.bz2
-
-Project files
-
-   1.2.10rc1-project-netware.zip
-   1.2.10rc1-project-wince.zip
+   lp170a10.7z  (LZMA-compressed, recommended)
+   lp170a10.zip
 
 Other information:
 
-   1.2.10rc1-README.txt
-   1.2.10rc1-KNOWNBUGS.txt
-   1.2.10rc1-LICENSE.txt
-   1.2.10rc1-Y2K-compliance.txt
+   1.7.0alpha10-README.txt
+   1.7.0alpha10-LICENSE.txt
 
-Changes since the last public release (1.2.9):
+Changes since the last public release (1.6.0):
 
-version 1.2.10beta1 [April 15, 2006]
-  Renamed "config.h" to "png_conf.h" and revised Makefile.am to add
-    -DPNG_BUILDING_LIBPNG to compile directive, and modified pngconf.h
-    to include png_conf.h only when PNG_BUILDING_LIBPNG is defined.
+Version 1.7.0alpha01 [December 15, 2012]
+  Started 1.7.0 branch from libpng-1.6.0beta33.
+  Made 8-bit compose and rgb_to_grayscale accuracy improvements.  These
+    changes cause 16-bit arithmetic to be used for 8-bit data in the gamma
+    corrected compose and grayscale operations.  The arithmetic errors have
+    three sources all of which are fixed in this commit:
+    1) 8-bit linear calculations produce massive errors for lower intensity
+       values.
+    2) The old 16-bit "16 to 8" gamma table code erroneously wrote the lowest
+       output value into a table entry which corresponded to multiple output
+       values (so where the value written should have been the closest to the
+       transformed input value.)
+    3) In a number of cases the code to access the 16-bit table did not round;
+       it did a simple shift, which was wrong and made the side effects of (2)
+       even worse.
+  The new gamma code does not have the 16-to-8 problem at the cost of slightly
+    more calculations and the algorithm used to minimize the number of
+    calculations has been extended to all the 16-bit tables; it has advantages
+    for any significant gamma correction.
+  Rearranged png_struct, remove unused members, change png_set_filter handling
+    png_struct members rearranged - partly to reorder to avoid packing, partly
+    to put frequently accessed members at the start and partly to make
+    the grouping more clear. png_set_filter code has been rewritten and the
+    code shared with png_write_start_row moved to a common function.  Comments
+    in png.h have been made more clear. Minor fixes to
+    contrib/libtests/timepng.c and some of the png_*_tRNS logic, including
+    more error detection in png_set_tRNS.
+  Cleaned up USER_LIMITS feature, removing members from png_struct when not
+    required.
+  Rearranged ARM-NEON optimizations to isolate the machine specific code to
+    the hardware subdirectory, and add comments to pngrutil.c so that
+    implementors of other optimizations will know what to do.
+  Fixed cases of unquoted DESTDIR in Makefile.am.
+  Rebuilt Makefile.in, configure, etc., with autoconf-2.69 and automake-1.12.5.
 
-version 1.2.10beta2 [April 15, 2006]
-  Manually updated Makefile.in and configure.  Changed png_conf.h.in
-    back to config.h.
+Version 1.7.0alpha02 [December 17, 2012]
+  Removed functions that were deprecated in libpng-1.6.0:
+    png_reset_zstream(), png_info_init_3(), and png_data_freer() and its
+    associated flags.
+  Removed some duplicated lines from contrib/tools/scale.c and png.c.
+  Changed some instances of png_warning() to png_app_error().
+  Updated some left over "1.6.0beta32" in code sources.
+  Fixed a "png_structp" prototype (should be png_structrp) in arm_init.c
+  Updated the version-number hack in pngvalid.c
 
-version 1.2.10beta3 [April 15, 2006]
-  Change png_conf.h back to config.h in pngconf.h.
+Version 1.7.0alpha03 [December 19, 2012]
+  Cleaned up and enhanced the configure option; libpng now correctly
+    links and tests against zlib with a prefix; tests have been clarified; and
+    irrelevant or obsolete things (as defined by the autotools man page) have
+    been removed.
+  Documented new PNG_ABORT behavior in the manual and commentary in pngerror.c
+  Cleaned up whitespace in the synopsis portion of the manpage "libpng.3"
+  Fixed previous support for Z_PREFIX in configure builds, corrected sCAL APIs;
+    some of these use floating point arithmetic so they need to be disabled if
+    floating point arithmetic is switched off.  This is a quiet API change -
+    previously it appeared that the APIs were supported if fixed point
+    arithmetic was used internally, however they required certain APIs (floor,
+    modf, frexp, atof) that are part of C floating point support. Changed
+    png_fixed and the gamma code specific version of the same to avoid floor(),
+    which may be a library function (not an intrinsic). Removed unused #if 0
+    code.
+  Disassembled the version number in scripts/options.awk (necessary for
+    building on SunOs).
 
-version 1.2.10beta4 [April 16, 2006]
-  Change PNG_BUILDING_LIBPNG to PNG_CONFIGURE_LIBPNG in config/Makefile*.
+Version 1.7.0alpha04 [December 23, 2012]
+  Added scripts/makefile.msys contributed by Christopher M. Wheeler
+  Made default Zlib compression settings be configurable. This adds #defines to
+    pnglibconf.h to control the defaults.
+  Fixed Windows build issues, enabled ARM compilation. Various warnings issued
+    by earlier versions of GCC fixed for Cygwin and Min/GW (which both use old
+    GCCs.) ARM support is enabled by default in zlib.props (unsupported by
+    Microsoft) and ARM compilation is made possible by deleting the check for
+    x86. The test programs cannot be run because they are not signed.
 
-version 1.2.10beta5 [April 16, 2006]
-  Added a configure check for compiling assembler code in pnggccrd.c
+Version 1.7.0alpha05 [December 24, 2012]
+  Discontinued distributing libpng-1.x.x.tar.bz2.
+  Discontinued distributing libpng-1.7.0-1.6.0-diff.txt and similar.
 
-version 1.2.10beta6 [April 17, 2006]
-  Revised the configure check for pnggccrd.c
-  Moved -DPNG_CONFIGURE_LIBPNG into @LIBPNG_DEFINES@
-  Added @LIBPNG_DEFINES@ to arguments when building libpng.sym
+Version 1.7.0alpha06 [January 1, 2013]
+  Fixed 'make distcheck' on SUN OS - libpng.so was not being removed
 
-version 1.2.10beta7 [April 18, 2006]
-  Change "exec_prefix=$prefix" to "exec_prefix=$(prefix)" in makefiles.
+Version 1.7.0alpha07 [January 10, 2013]
+  Fixed conceivable but difficult to repro overflow. Also added two test
+    programs to generate and test a PNG which should have the problem.
 
-version 1.2.10beta8 [April 19, 2006]
-  Ensure pngconf.h doesn't define both PNG_USE_PNGGCCRD and PNG_USE_PNGVCRD
-  Fixed "LN_FS" typo in makefile.sco and makefile.solaris.
+Version 1.7.0alpha08 [January 17, 2013]
+  Corrected previous attempt at overflow detection in png_set_unknown_chunks().
+
+Version 1.7.0alpha09 [January 21, 2013]
+  Pulled changes to multi-chunk handling from libpng-1.6.0beta40.
+
+Version 1.7.0alpha10 [February 7, 2013]
+  Make symbol prefixing work with the ARM neon optimizations. Also
+    allow pngpriv.h to be included for preprocessor definitions only, so
+    it can be used in non-C/C++ files.
+  Added png_get_palette_max() function.
+  Changed png_size_t to size_t throughout headers, make sRGB check numbers
+    consistent.
+  Fixed ARM support (Mans Rullgard).
+  Removed stray out-of-order #endif and #ifdef (Mans Rullgard).
+  Ported libpng 1.5 options.awk/dfn file handling to 1.7, fixed one bug.
+  Rebuilt Makefile.in, configure, etc., with autoconf-2.69 and automake-1.13.
+  Minor fixes to assembler changes, verified with a dummy .S file
+  Removed cc -E workround, corrected png_get_palette_max API. Tested on
+    SUN OS cc 5.9, which demonstrates the tokenization problem previously
+    avoided by using /lib/cpp.  Since all .dfn output is now protected
+    in double quotes unless it is to be macro substituted the fix should work
+    everywhere.
+
+  ===========================================================================
+                       NOTICE November 17, 2012:
+     The location of the git repository at SourceForge has changed.
+               Visit http://libpng.sf.net/ for details.
+  ===========================================================================
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement
-to subscribe) or to glennrp at users.sourceforge.net
+to subscribe)
+or to glennrp at users.sourceforge.net
 
 Glenn R-P

CMakeLists.txt

@@ -0,0 +1,379 @@
+# CMakeLists.txt
+
+# Copyright (C) 2007-2011 Glenn Randers-Pehrson
+
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+cmake_minimum_required(VERSION 2.4.4)
+set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS true)
+
+if(UNIX AND NOT DEFINED CMAKE_BUILD_TYPE)
+  if(CMAKE_MAJOR_VERSION EQUAL 2 AND CMAKE_MINOR_VERSION EQUAL 4)
+    # workaround CMake 2.4.x bug
+    set(CMAKE_BUILD_TYPE "RelWithDebInfo" CACHE STRING
+        "Choose the type of build, options are:
+           None(CMAKE_CXX_FLAGS or CMAKE_C_FLAGS used)
+           Debug
+           Release
+           RelWithDebInfo
+           MinSizeRel.")
+  else()
+    set(CMAKE_BUILD_TYPE "RelWithDebInfo" CACHE STRING
+        "Choose the type of build, options are:
+           None(CMAKE_CXX_FLAGS or CMAKE_C_FLAGS used)
+           Debug
+           Release
+           RelWithDebInfo
+           MinSizeRel.")
+  endif()
+endif()
+
+project(libpng C)
+enable_testing()
+
+set(PNGLIB_MAJOR 1)
+set(PNGLIB_MINOR 7)
+set(PNGLIB_RELEASE 0)
+set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
+set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})
+
+# needed packages
+find_package(ZLIB REQUIRED)
+include_directories(${ZLIB_INCLUDE_DIR})
+
+if(NOT WIN32)
+  find_library(M_LIBRARY
+    NAMES m
+    PATHS /usr/lib /usr/local/lib
+  )
+  if(NOT M_LIBRARY)
+    message(STATUS
+      "math library 'libm' not found - floating point support disabled")
+  endif()
+else()
+  # not needed on windows
+  set(M_LIBRARY "")
+endif()
+
+# COMMAND LINE OPTIONS
+if(DEFINED PNG_SHARED)
+  option(PNG_SHARED "Build shared lib" ${PNG_SHARED})
+else()
+  option(PNG_SHARED "Build shared lib" ON)
+endif()
+if(DEFINED PNG_STATIC)
+  option(PNG_STATIC "Build static lib" ${PNG_STATIC})
+else()
+  option(PNG_STATIC "Build static lib" ON)
+endif()
+
+option(PNG_TESTS  "Build libpng tests" YES)
+
+# Many more configuration options could be added here
+option(PNG_DEBUG         "Build with debug output" NO)
+option(PNGARG            "Disable ANSI-C prototypes" NO)
+
+# SET LIBNAME
+set(PNG_LIB_NAME png${PNGLIB_MAJOR}${PNGLIB_MINOR})
+
+# to distinguish between debug and release lib
+set(CMAKE_DEBUG_POSTFIX "d")
+
+# Use the prebuilt pnglibconf.h file from the scripts folder
+# TODO: fix this by building with awk; without this no cmake build can be
+# configured directly (to do so indirectly use your local awk to build a
+# pnglibconf.h in the build directory.)
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt
+               ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h)
+include_directories(${CMAKE_CURRENT_BINARY_DIR})
+
+# OUR SOURCES
+set(libpng_public_hdrs
+  png.h
+  pngconf.h
+  ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h
+)
+set(libpng_sources
+  ${libpng_public_hdrs}
+  pngdebug.h
+  pnginfo.h
+  pngpriv.h
+  pngstruct.h
+  png.c
+  pngerror.c
+  pngget.c
+  pngmem.c
+  pngpread.c
+  pngread.c
+  pngrio.c
+  pngrtran.c
+  pngrutil.c
+  pngset.c
+  pngtrans.c
+  pngwio.c
+  pngwrite.c
+  pngwtran.c
+  pngwutil.c
+)
+set(pngtest_sources
+  pngtest.c
+)
+set(pngvalid_sources
+  contrib/libtests/pngvalid.c
+)
+set(pngstest_sources
+  contrib/libtests/pngstest.c
+)
+# SOME NEEDED DEFINITIONS
+
+if(MSVC)
+  add_definitions(-D_CRT_SECURE_NO_DEPRECATE)
+endif(MSVC)
+
+if(PNG_DEBUG)
+  add_definitions(-DPNG_DEBUG)
+endif()
+
+# NOW BUILD OUR TARGET
+include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${ZLIB_INCLUDE_DIR})
+
+if(PNG_SHARED)
+  add_library(${PNG_LIB_NAME} SHARED ${libpng_sources})
+  if(MSVC)
+    # msvc does not append 'lib' - do it here to have consistent name
+    set_target_properties(${PNG_LIB_NAME} PROPERTIES PREFIX "lib")
+    set_target_properties(${PNG_LIB_NAME} PROPERTIES IMPORT_PREFIX "lib")
+  endif()
+  target_link_libraries(${PNG_LIB_NAME} ${ZLIB_LIBRARY} ${M_LIBRARY})
+endif()
+
+if(PNG_STATIC)
+# does not work without changing name
+  set(PNG_LIB_NAME_STATIC ${PNG_LIB_NAME}_static)
+  add_library(${PNG_LIB_NAME_STATIC} STATIC ${libpng_sources})
+  if(MSVC)
+    # msvc does not append 'lib' - do it here to have consistent name
+    set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES PREFIX "lib")
+  endif()
+  target_link_libraries(${PNG_LIB_NAME_STATIC} ${ZLIB_LIBRARY} ${M_LIBRARY})
+endif()
+
+if(PNG_SHARED AND WIN32)
+  set_target_properties(${PNG_LIB_NAME} PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)
+endif()
+
+if(PNG_TESTS AND PNG_SHARED)
+  # does not work with msvc due to png_lib_ver issue
+  add_executable(pngtest ${pngtest_sources})
+  target_link_libraries(pngtest ${PNG_LIB_NAME})
+  add_test(pngtest ./pngtest ${CMAKE_CURRENT_SOURCE_DIR}/pngtest.png)
+  #
+  add_executable(pngvalid ${pngvalid_sources})
+  target_link_libraries(pngvalid ${PNG_LIB_NAME})
+  add_test(pngvalid ./pngvalid)
+  add_executable(pngstest ${pngstest_sources})
+  target_link_libraries(pngstest ${PNG_LIB_NAME})
+  add_test(pngstest ./pngstest
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g01.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g02.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g04.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn0g16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn2c08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn2c16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p01.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p02.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p04.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn4a08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn4a16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn6a08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/basn6a16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g01.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g02.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn0g04.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn2c16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbbn3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbgn2c16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbgn3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbrn2c08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbwn0g16.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbwn3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftbyn3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n0g08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n2c08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp0n3p08.png
+    ${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/ftp1n3p08.png
+  )
+endif()
+
+# Ensure the CMAKE_LIBRARY_OUTPUT_DIRECTORY is set
+IF(NOT CMAKE_LIBRARY_OUTPUT_DIRECTORY)
+  SET(CMAKE_LIBRARY_OUTPUT_DIRECTORY "lib")
+ENDIF(NOT CMAKE_LIBRARY_OUTPUT_DIRECTORY)
+
+# Set a variable with CMake code which:
+# Creates a symlink from src to dest (if possible) or alternatively
+# copies if different.
+macro(CREATE_SYMLINK SRC_FILE DEST_FILE)
+  FILE(REMOVE ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE})
+  if(WIN32 AND NOT CYGWIN AND NOT MSYS)
+    ADD_CUSTOM_COMMAND(
+        OUTPUT ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE}   ${CMAKE_CURRENT_BINARY_DIR}/${DEST_FILE}
+        COMMAND ${CMAKE_COMMAND} -E copy        ${CMAKE_CURRENT_BINARY_DIR}/${SRC_FILE} ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE}
+        COMMAND ${CMAKE_COMMAND} -E copy        ${CMAKE_CURRENT_BINARY_DIR}/${SRC_FILE} ${CMAKE_CURRENT_BINARY_DIR}/${DEST_FILE}
+        DEPENDS ${PNG_LIB_NAME} ${PNG_LIB_NAME_STATIC}
+        )
+    ADD_CUSTOM_TARGET(${DEST_FILE}_COPY ALL DEPENDS ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE})
+  else(WIN32 AND NOT CYGWIN AND NOT MSYS)
+    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink ${SRC_FILE} ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink ${SRC_FILE} ${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+  endif(WIN32 AND NOT CYGWIN AND NOT MSYS)
+endmacro()
+
+# libpng is a library so default to 'lib'
+if(NOT DEFINED CMAKE_INSTALL_LIBDIR)
+  set(CMAKE_INSTALL_LIBDIR lib)
+endif(NOT DEFINED CMAKE_INSTALL_LIBDIR)
+
+# CREATE PKGCONFIG FILES
+# we use the same files like ./configure, so we have to set its vars
+# Only do this on Windows for Cygwin - the files don't make much sense outside
+# a UNIX look alike
+if(NOT WIN32 OR CYGWIN OR MINGW)
+  set(prefix      ${CMAKE_INSTALL_PREFIX})
+  set(exec_prefix ${CMAKE_INSTALL_PREFIX})
+  set(libdir      ${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR})
+  set(includedir  ${CMAKE_INSTALL_PREFIX}/include)
+  set(LIBS        "-lz -lm")
+  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng.pc.in
+    ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc @ONLY)
+  CREATE_SYMLINK(${PNGLIB_NAME}.pc libpng.pc)
+
+  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng-config.in
+    ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config @ONLY)
+  CREATE_SYMLINK(${PNGLIB_NAME}-config libpng-config)
+endif(NOT WIN32 OR CYGWIN OR MINGW)
+
+# SET UP LINKS
+if(PNG_SHARED)
+  set_target_properties(${PNG_LIB_NAME} PROPERTIES
+#   VERSION 17.${PNGLIB_RELEASE}.1.7.0alpha10
+    VERSION 17.${PNGLIB_RELEASE}.0
+    SOVERSION 17
+    CLEAN_DIRECT_OUTPUT 1)
+endif()
+if(PNG_STATIC)
+  # MSVC doesn't use a different file extension for shared vs. static
+  # libs.  We are able to change OUTPUT_NAME to remove the _static
+  # for all other platforms.
+  if(NOT MSVC)
+    set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES
+      OUTPUT_NAME ${PNG_LIB_NAME}
+      CLEAN_DIRECT_OUTPUT 1)
+  endif()
+endif()
+
+# If CMake > 2.4.x, we set a variable used below to export
+# targets to an export file.
+# TODO: Use VERSION_GREATER after our cmake_minimum_required >= 2.6.2
+if(CMAKE_MAJOR_VERSION GREATER 1 AND CMAKE_MINOR_VERSION GREATER 4)
+  set(PNG_EXPORT_RULE EXPORT libpng)
+elseif(CMAKE_MAJOR_VERSION GREATER 2) # future proof
+  set(PNG_EXPORT_RULE EXPORT libpng)
+endif()
+
+# INSTALL
+if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
+  if(PNG_SHARED)
+    install(TARGETS ${PNG_LIB_NAME}
+        ${PNG_EXPORT_RULE}
+        RUNTIME DESTINATION bin
+        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})
+
+    # Create a symlink for libpng.dll.a => libpng17.dll.a on Cygwin
+    if(CYGWIN OR MINGW)
+       get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})
+       get_filename_component(BUILD_TARGET_FILE ${BUILD_TARGET_LOCATION} NAME)
+       CREATE_SYMLINK(${BUILD_TARGET_FILE} libpng${CMAKE_IMPORT_LIBRARY_SUFFIX})
+       install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_IMPORT_LIBRARY_SUFFIX}
+         DESTINATION ${CMAKE_INSTALL_LIBDIR})
+    endif(CYGWIN OR MINGW)
+
+    if(NOT WIN32)
+      get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})
+      get_filename_component(BUILD_TARGET_FILE ${BUILD_TARGET_LOCATION} NAME)
+      CREATE_SYMLINK(${BUILD_TARGET_FILE} libpng${CMAKE_SHARED_LIBRARY_SUFFIX})
+      install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_SHARED_LIBRARY_SUFFIX}
+         DESTINATION ${CMAKE_INSTALL_LIBDIR})
+    endif(NOT WIN32)
+  endif(PNG_SHARED)
+
+  if(PNG_STATIC)
+    install(TARGETS ${PNG_LIB_NAME_STATIC}
+        ${PNG_EXPORT_RULE}
+        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR})
+    if(NOT WIN32 OR CYGWIN OR MINGW)
+      get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME_STATIC} LOCATION_${CMAKE_BUILD_TYPE})
+      get_filename_component(BUILD_TARGET_FILE ${BUILD_TARGET_LOCATION} NAME)
+      CREATE_SYMLINK(${BUILD_TARGET_FILE} libpng${CMAKE_STATIC_LIBRARY_SUFFIX})
+      install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${CMAKE_STATIC_LIBRARY_SUFFIX}
+         DESTINATION ${CMAKE_INSTALL_LIBDIR})
+    endif(NOT WIN32 OR CYGWIN OR MINGW)
+ endif()
+endif()
+
+if(NOT SKIP_INSTALL_HEADERS AND NOT SKIP_INSTALL_ALL )
+  install(FILES ${libpng_public_hdrs}   DESTINATION include)
+  install(FILES ${libpng_public_hdrs}   DESTINATION include/${PNGLIB_NAME})
+endif()
+if(NOT SKIP_INSTALL_EXECUTABLES AND NOT SKIP_INSTALL_ALL )
+  if(NOT WIN32 OR CYGWIN OR MINGW)
+    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config DESTINATION bin)
+    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config
+            DESTINATION bin)
+  endif(NOT WIN32 OR CYGWIN OR MINGW)
+endif()
+
+if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
+  # Install man pages
+  if(NOT PNG_MAN_DIR)
+    set(PNG_MAN_DIR "share/man")
+  endif()
+  install(FILES libpng.3 libpngpf.3      DESTINATION ${PNG_MAN_DIR}/man3)
+  install(FILES png.5                    DESTINATION ${PNG_MAN_DIR}/man5)
+  # Install pkg-config files
+  if(NOT WIN32 OR CYGWIN OR MINGW)
+    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng.pc
+            DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
+    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config
+            DESTINATION bin)
+    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc
+            DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
+    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config
+            DESTINATION bin)
+  endif(NOT WIN32 OR CYGWIN OR MINGW)
+endif()
+
+# On versions of CMake that support it, create an export file CMake
+# users can include() to import our targets
+if(PNG_EXPORT_RULE AND NOT SKIP_INSTALL_EXPORT AND NOT SKIP_INSTALL_ALL )
+  install(EXPORT libpng DESTINATION lib/libpng FILE lib${PNG_LIB_NAME}.cmake)
+endif()
+
+# what's with libpng-$VER%.txt and all the extra files?
+
+# UNINSTALL
+# do we need this?
+
+# DIST
+# do we need this?
+
+# to create msvc import lib for mingw compiled shared lib
+# pexports libpng.dll > libpng.def
+# lib /def:libpng.def /machine:x86
+

INSTALL

@@ -1,22 +1,39 @@
 
-Installing libpng version 1.2.10rc1 - April 19, 2006
+Installing libpng
 
 On Unix/Linux and similar systems, you can simply type
 
-    ./autogen.sh
-    ./configure [--prefix=$HOME]
+    ./configure [--prefix=/path]
     make check
     make install
 
 and ignore the rest of this document.
 
-Or you can use one of the custom-built makefiles in the
+If configure does not work on your system, or if you have a need to
+change configure.ac or Makefile.am, and you have a reasonably
+up-to-date set of tools, running ./autogen.sh in a git clone before
+running ./configure may fix the problem.  To be really sure that you
+aren't using any of the included pre-built scripts, you can do this:
+
+    ./configure --enable-maintainer-mode
+    make maintainer-clean
+    ./autogen.sh --maintainer --clean
+    ./autogen.sh --maintainer
+    ./configure [--prefix=/path] [other options]
+    make
+    make install
+    make check
+
+Instead, you can use one of the custom-built makefiles in the
 "scripts" directory
 
     cp scripts/makefile.system makefile
     make test
     make install
 
+The files that are presently available in the scripts directory
+are listed and described in scripts/README.txt.
+
 Or you can use one of the "projects" in the "projects" directory.
 
 Before installing libpng, you must first install zlib, if it
@@ -24,13 +41,19 @@ is not already on your system.  zlib can usually be found
 wherever you got libpng.  zlib can be placed in another directory,
 at the same level as libpng.
 
+If you want to use "cmake" (see www.cmake.org), type
+
+   cmake . -DCMAKE_INSTALL_PREFIX=/path
+   make
+   make install
+
 If your system already has a preinstalled zlib you will still need
 to have access to the zlib.h and zconf.h include files that
 correspond to the version of zlib that's installed.
 
 You can rename the directories that you downloaded (they
-might be called "libpng-1.2.10rc1" or "lpng109" and "zlib-1.2.1"
-or "zlib121") so that you have directories called "zlib" and "libpng".
+might be called "libpng-x.y.z" or "libpngNN" and "zlib-1.2.5"
+or "zlib125") so that you have directories called "zlib" and "libpng".
 
 Your directory structure should look like this:
 
@@ -40,19 +63,25 @@ Your directory structure should look like this:
           README
           *.h
           *.c
+          CMakeLists.txt    =>  "cmake" script
+          configuration files:
+             configure.ac, configure, Makefile.am, Makefile.in,
+             autogen.sh, config.guess, ltmain.sh, missing, libpng.pc.in,
+             libpng-config.in, aclocal.m4, config.h.in, config.sub,
+             depcomp, install-sh, mkinstalldirs, test-pngtest.sh
           contrib
              gregbook
+             pngminim
              pngminus
              pngsuite
              visupng
           projects
-             beos
-             c5builder (Borland)
-             visualc6 (msvc)
-             netware.txt
-             wince.txt
+             visualc71
+             vstudio
           scripts
              makefile.*
+             *.def (module definition files)
+             etc.
           pngtest.png
           etc.
       zlib
@@ -67,83 +96,13 @@ distribution of libpng.  It is available in both tar.gz (UNIX style line
 endings) and zip (DOS style line endings) formats.
 
 If you are building libpng with MSVC, you can enter the
-libpng projects\visualc6 directory and follow the instructions in
-projects\visualc6\README.txt.
+libpng projects\visualc6 or visualc71 directory and follow the instructions
+in README.txt.
 
-You can build libpng for WindowsCE by downloading and installing
-the projects\wince directory as instructed in the projects\wince.txt file, and
-then following the instructions in the README* files.  Similarly, you can
-build libpng for Netware or Beos as instructed in projects\netware.txt
-or projects\beos.
-
-Else enter the zlib directory and follow the instructions in zlib/README,
+Otherwise enter the zlib directory and follow the instructions in zlib/README,
 then come back here and run "configure" or choose the appropriate
 makefile.sys in the scripts directory.
 
-The files that are presently available in the scripts directory
-include
-
- makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a)
- makefile.elf      =>  Linux/ELF makefile symbol versioning,
-                       gcc, creates libpng12.so.0.1.2.10rc1)
- makefile.linux    =>  Linux/ELF makefile
-                       (gcc, creates libpng12.so.0.1.2.10rc1)
- makefile.gcmmx    =>  Linux/ELF makefile
-                       (gcc, creates libpng12.so.0.1.2.10rc1,
-                       uses assembler code tuned for Intel MMX platform)
- makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a)
- makefile.knr      =>  Archaic UNIX Makefile that converts files with
-                       ansi2knr (Requires ansi2knr.c from
-                       ftp://ftp.cs.wisc.edu/ghost)
- makefile.aix      =>  AIX/gcc makefile
- makefile.cygwin   =>  Cygwin/gcc makefile
- makefile.darwin   =>  Darwin makefile, can use on MacosX
- makefile.dec      =>  DEC Alpha UNIX makefile
- makefile.freebsd  =>  FreeBSD makefile
- makefile.hpgcc    =>  HPUX makefile using gcc
- makefile.hpux     =>  HPUX (10.20 and 11.00) makefile
- makefile.hp64     =>  HPUX (10.20 and 11.00) makefile, 64-bit
- makefile.ibmc     =>  IBM C/C++ version 3.x for Win32 and OS/2 (static)
- makefile.intel    =>  Intel C/C++ version 4.0 and later
- libpng.icc        =>  Project file for IBM VisualAge/C++ version 4.0 or later
- makefile.netbsd   =>  NetBSD/cc makefile, uses PNGGCCRD, makes libpng.so.
- makefile.ne12bsd  =>  NetBSD/cc makefile, uses PNGGCCRD,
-                       makes libpng12.so
- makefile.openbsd  =>  OpenBSD makefile
- makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
- makefile.sggcc    =>  Silicon Graphics (gcc,
-                       creates libpng12.so.0.1.2.10rc1)
- makefile.sunos    =>  Sun makefile
- makefile.solaris  =>  Solaris 2.X makefile (gcc,
-                       creates libpng12.so.0.1.2.10rc1)
- makefile.so9      =>  Solaris 9 makefile (gcc,
-                       creates libpng12.so.0.1.2.10rc1)
- makefile.32sunu   =>  Sun Ultra 32-bit makefile
- makefile.64sunu   =>  Sun Ultra 64-bit makefile
- makefile.sco      =>  For SCO OSr5  ELF and Unixware 7 with Native cc
- makefile.mips     =>  MIPS makefile
- makefile.acorn    =>  Acorn makefile
- makefile.amiga    =>  Amiga makefile
- smakefile.ppc     =>  AMIGA smakefile for SAS C V6.58/7.00 PPC compiler
-                       (Requires SCOPTIONS, copied from scripts/SCOPTIONS.ppc)
- makefile.atari    =>  Atari makefile
- makefile.beos     =>  BEOS makefile for X86
- makefile.bor      =>  Borland makefile (uses bcc)
- makefile.bc32     =>  32-bit Borland C++ (all modules compiled in C mode)
- makefile.tc3      =>  Turbo C 3.0 makefile
- makefile.dj2      =>  DJGPP 2 makefile
- makefile.msc      =>  Microsoft C makefile
- makefile.vcawin32 =>  makefile for Microsoft Visual C++ 5.0 and later (uses
-                       assembler code tuned for Intel MMX platform)
- makefile.vcwin32  =>  makefile for Microsoft Visual C++ 4.0 and later (does
-                       not use assembler code)
- makefile.os2      =>  OS/2 Makefile (gcc and emx, requires pngos2.def)
- pngos2.def        =>  OS/2 module definition file used by makefile.os2
- makefile.watcom   =>  Watcom 10a+ Makefile, 32-bit flat memory model
- makevms.com       =>  VMS build script
- descrip.mms       =>  VMS makefile for MMS or MMK
- SCOPTIONS.ppc     =>  Used with smakefile.ppc
-
 Copy the file (or files) that you need from the
 scripts directory into this directory, for example
 
@@ -153,7 +112,7 @@ scripts directory into this directory, for example
 Read the makefile to see if you need to change any source or
 target directories to match your preferences.
 
-Then read pngconf.h to see if you want to make any configuration
+Then read pnglibconf.dfa to see if you want to make any configuration
 changes.
 
 Then just run "make" which will create the libpng library in
@@ -171,37 +130,26 @@ do that, run "make install" in the zlib directory first if necessary).
 Some also allow you to run "make test-installed" after you have
 run "make install".
 
-If you encounter a compiler error message complaining about the
-lines
-      __png.h__ already includes setjmp.h;
-      __dont__ include it again.;
-This means you have compiled another module that includes setjmp.h,
-which is hazardous because the two modules might not include exactly
-the same setjmp.h.  If you are sure that you know what you are doing
-and that they are exactly the same, then you can comment out or
-delete the two lines.  Better yet, use the cexcept interface
-instead, as demonstrated in contrib/visupng of the libpng distribution.
-
-Further information can be found in the README and libpng.txt
+Further information can be found in the README and libpng-manual.txt
 files, in the individual makefiles, in png.h, and the manual pages
 libpng.3 and png.5.
 
-
 Using the ./configure script -- 16 December 2002.
 =================================================
 
-
 The ./configure script should work compatibly with what scripts/makefile.*
-did, however there are some options you need to add to configure explicitly,
-which previously was done semi-automatically (if you didn't edit
+did, however there are some options you might need to add to configure
+explicitly, which previously was done semi-automatically (if you didn't edit
 scripts/makefile.* yourself, that is)
 
-
-CFLAGS="-Wall -O3 -funroll-loops \
+CFLAGS="-Wall -O -funroll-loops \
 -malign-loops=2 -malign-functions=2" ./configure --prefix=/usr/include \
 --with-pkgconfigdir=/usr/lib/pkgconfig --includedir=/usr/include
 
 You can alternatively specify --includedir=/usr/include, /usr/local/include,
-/usr/include/png12, or whatever.
+/usr/include/libpng%NN%, or whatever.
 
+If you find that the configure script is out-of-date or is not supporting
+your platform properly, try running autogen.sh to regenerate "configure",
+"Makefile.in", and the other configuration files. Then try configure again.
 

KNOWNBUG

@@ -1,23 +0,0 @@
-
-Known bugs in libpng version 1.2.10rc1
-
-1. April 22, 2001: pnggccrd.c has been reported to crash on NetBSD when
-   reading interlaced PNG files, when assembler code is enabled but running
-   on a non-MMX i386 platform.
-
-   STATUS: Under investigation.  The change to pnggccrd.c in libpng-1.2.1
-   fixed a problem under FreeBSD but not the problem with NetBSD, which
-   still fails as of libpng-1.2.2rc1.
-
-2. February 23, 2006: The custom makefiles don't build libpng with -lz.
-
-   STATUS: This is a subject of debate. The change will probably be made
-   as a part of a major overhaul of the makefiles in libpng version 1.3.0.
-
-3. February 24, 2006: The Makefile generated by the "configure" script
-   fails to install symbolic links
-   libpng12.so => libpng12.so.0.1.2.9betaN
-   that are generated by the custom makefiles.
-
-   STATUS: For now, system library builders should use the custom makefiles.
-

LICENSE

@@ -8,8 +8,10 @@ COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
 If you modify libpng you may insert additional notices immediately following
 this sentence.
 
-libpng versions 1.2.6, August 15, 2004, through 1.2.10rc1, April 19, 2006, are
-Copyright (c) 2004, 2006 Glenn Randers-Pehrson, and are
+This code is released under the libpng license.
+
+libpng versions 1.2.6, August 15, 2004, through 1.7.0alpha10, February 7, 2013, are
+Copyright (c) 2004, 2006-2013 Glenn Randers-Pehrson, and are
 distributed according to the same disclaimer and license as libpng-1.2.5
 with the following individual added to the list of Contributing Authors
 
@@ -106,4 +108,4 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-April 19, 2006
+February 7, 2013

Makefile.am

@@ -1,91 +1,114 @@
 # Makefile.am:
 #   Source file for Makefile.in (and hence Makefile)
 #
-# Makefile.am need only be changed on a major version number
-# change (e.g. libpng12 --> libpng13).  In that case seach
-# this file for every instance of the old base name (libpng12)
-# and change to the new one (libpng13), then change the
-# -version-number settings below so that the new values have
-# the correct major part (first field).
 
-PNGLIB_BASENAME= libpng@PNGLIB_MAJOR@
+PNGLIB_BASENAME= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@
 
-# libpng does not follow GNU file name conventions
-AUTOMAKE_OPTIONS = foreign
+ACLOCAL_AMFLAGS = -I scripts
 
 # test programs - run on make check, make distcheck
+TESTS_ENVIRONMENT= srcdir=$(srcdir)
 check_PROGRAMS= pngtest
 pngtest_SOURCES = pngtest.c
-pngtest_LDADD = libpng12.la
+pngtest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 TESTS = test-pngtest.sh
-TESTS_ENVIRONMENT= srcdir=$(srcdir) 
+
+# Only do the following if the contrib directory is present.
+check_PROGRAMS+= pngvalid pngstest pngunknown
+pngvalid_SOURCES = contrib/libtests/pngvalid.c
+pngstest_SOURCES = contrib/libtests/pngstest.c
+pngunknown_SOURCES = contrib/libtests/pngunknown.c
+pngvalid_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+pngstest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+pngunknown_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+TESTS += contrib/libtests/test-pngunknown.sh\
+	 contrib/libtests/test-pngvalid-simple.sh\
+	 contrib/libtests/test-pngvalid-full.sh\
+	 contrib/libtests/test-pngstest.sh
 
 # man pages
 dist_man_MANS= libpng.3 libpngpf.3 png.5
 
 # generate the -config scripts if required
-binconfigs= libpng12-config 
-EXTRA_SCRIPTS= libpng-config libpng12-config
+binconfigs= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@-config
+EXTRA_SCRIPTS= libpng-config libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@-config
 bin_SCRIPTS= @binconfigs@
 
 # rules to build libpng, only build the old library on request
-lib_LTLIBRARIES=libpng12.la @compatlib@
-EXTRA_LTLIBRARIES= libpng.la
-libpng12_la_SOURCES = png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
-	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
-	pngwtran.c pngmem.c pngerror.c pngpread.c pnggccrd.c \
-	png.h pngconf.h
-libpng_la_SOURCES = $(libpng12_la_SOURCES)
+lib_LTLIBRARIES=libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+# EXTRA_LTLIBRARIES= libpng.la
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = png.c pngerror.c\
+	pngget.c pngmem.c pngpread.c pngread.c pngrio.c pngrtran.c pngrutil.c\
+	pngset.c pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c\
+	png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h pngusr.dfa
 
-libpng_la_CPPFLAGS = @LIBPNG_DEFINES@
-libpng12_la_CPPFLAGS = @LIBPNG_DEFINES@
+if PNG_ARM_NEON
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += arm/arm_init.c\
+	arm/filter_neon.S
+endif
 
-# MAJOR UPGRADE: the version-number settings below must be changed.
-libpng12_la_LDFLAGS = -no-undefined -export-dynamic \
-	-version-number 0:@PNGLIB_MINOR@:0
-# -rpath is needed as automake doesn't know the directory
-libpng_la_LDFLAGS = -rpath '$(libdir)' -no-undefined -export-dynamic \
-	-version-number 3:@PNGLIB_MINOR@:0
+nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h
+
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS = -no-undefined -export-dynamic \
+	-version-number @PNGLIB_MAJOR@@PNGLIB_MINOR@:@PNGLIB_RELEASE@:0
 
 if HAVE_LD_VERSION_SCRIPT
-  # Versioned symbols and restricted exports
-  libpng12_la_LDFLAGS += -Wl,--version-script=libpng.vers
-  libpng12_la_DEPENDENCIES = libpng.vers
+#   Versioned symbols and restricted exports
+if HAVE_SOLARIS_LD
+  libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS += -Wl,-M -Wl,libpng.vers
 else
-  # Only restricted exports when possible
-  libpng12_la_LDFLAGS += -export-symbols libpng.sym
-  libpng12_la_DEPENDENCIES = libpng.sym
+  libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS += -Wl,--version-script=libpng.vers
+endif
+
+  libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng.vers
+else
+#   Only restricted exports when possible
+  libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS += -export-symbols libpng.sym
+  libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng.sym
 endif
-libpng_la_DEPENDENCIES = $(libpng12_la_DEPENDENCIES)
 
 #distribute headers in /usr/include/libpng/*
 pkgincludedir= $(includedir)/$(PNGLIB_BASENAME)
 pkginclude_HEADERS= png.h pngconf.h
+nodist_pkginclude_HEADERS= pnglibconf.h
 
 # pkg-config stuff, note that libpng.pc is always required in order
 # to get the correct library
 pkgconfigdir = @pkgconfigdir@
-pkgconfig_DATA = libpng12.pc
+pkgconfig_DATA = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.pc
 
 #extra source distribution files.
 EXTRA_DIST= \
-	ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO Y2KINFO \
+	ANNOUNCE CHANGES INSTALL LICENSE README TODO \
 	pngtest.png pngbar.png pngnow.png pngbar.jpg autogen.sh \
-	${srcdir}/projects/cbuilder5/* \
-	${srcdir}/projects/beos/* \
-	${srcdir}/projects/visualc6/* \
-	${srcdir}/projects/visualc71/* \
-	${srcdir}/projects/wince.txt \
-	${srcdir}/projects/netware.txt \
-	${srcdir}/scripts/* \
-	${srcdir}/contrib/gregbook/* \
-	${srcdir}/contrib/pngminus/* \
-	${srcdir}/contrib/pngsuite/* \
-	${srcdir}/contrib/visupng/* \
+	${srcdir}/contrib ${srcdir}/projects ${srcdir}/scripts \
 	$(TESTS) \
-	example.c libpng.txt pngvcrd.c 
+	CMakeLists.txt example.c libpng-manual.txt
 
-CLEANFILES= pngout.png libpng12.pc libpng12-config libpng.vers libpng.sym
+SCRIPT_CLEANFILES=scripts/*.out scripts/*.chk scripts/pnglibconf.dfn
+
+CLEANFILES= *.tf? pngout.png libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.pc \
+	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@-config libpng.vers libpng.sym \
+	check.new pnglibconf.* pngprefix.h symbols.new pngtest-log.txt \
+	$(SCRIPT_CLEANFILES)
+
+MAINTAINERCLEANFILES = Makefile.in aclocal.m4 config.guess config.h.in \
+config.sub configure depcomp install-sh ltmain.sh missing
+
+# PNG_COPTS give extra options for the C compiler to be used on all compilation
+# steps (unless targe_CFLAGS is specified; that will take precedence over
+# AM_CFLAGS)
+PNG_COPTS = @PNG_COPTS@
+AM_CFLAGS = ${PNG_COPTS}
+
+# DFNCPP is normally just CPP - the C preprocessor - but on Solaris and maybe
+# other operating systems (NeXT?) the C preprocessor selected by configure
+# checks input tokens for validity - effectively it performs part of the ANSI-C
+# parsing - and therefore fails with the .df files.  configure.ac has special
+# checks for this and sets DFNCPP appropriately.
+DFNCPP = @DFNCPP@
+
+SUFFIXES = .chk .dfn .out
 
 $(PNGLIB_BASENAME).pc: libpng.pc
 	cp libpng.pc $@
@@ -93,51 +116,159 @@ $(PNGLIB_BASENAME).pc: libpng.pc
 $(PNGLIB_BASENAME)-config: libpng-config
 	cp libpng-config $@
 
-libpng.sym: png.h pngconf.h
-	rm -f $@ $@.new
-	$(CPP) @LIBPNG_DEFINES@ $(CPPFLAGS) -DPNG_BUILDSYMS $(srcdir)/png.h | \
-		$(SED) -n -e 's|^.*PNG_FUNCTION_EXPORT[ 	]*\([a-zA-Z0-9_]*\).*$$|\1|p' \
-			-e 's|^.*PNG_DATA_EXPORT[ 	]*\([a-zA-Z0-9_]*\).*$$|\1|p' \
-			>$@.new
-	mv $@.new $@
+scripts/sym.out scripts/vers.out: png.h pngconf.h pnglibconf.h
+scripts/prefix.out: png.h pngconf.h pnglibconf.out
+scripts/symbols.out: png.h pngconf.h $(srcdir)/scripts/pnglibconf.h.prebuilt
 
-libpng.vers: libpng.sym
-	rm -f $@ $@.new
-	$(ECHO) PNG@PNGLIB_MAJOR@_0 '{global:' > $@.new
-	$(SED) s/$$/\;/ libpng.sym >> $@.new
-	$(ECHO) 'local: *; };' >> $@.new
-	mv $@.new $@
+pnglibconf.out: config.h
+
+libpng.sym: scripts/sym.out
+	rm -f $@
+	cp $? $@
+libpng.vers: scripts/vers.out
+	rm -f $@
+	cp $? $@
+
+if DO_PNG_PREFIX
+# Rename functions in scripts/prefix.out with a PNG_PREFIX prefix.
+# Rename macros in scripts/macro.lst from PNG_PREFIXpng_ to PNG_ (the actual
+# implementation of the macro).
+pnglibconf.h: pnglibconf.out scripts/prefix.out scripts/macro.lst config.h
+	rm -f $@
+	$(AWK) 's==0 && NR>1{print prev}\
+	   s==0{prev=$$0}\
+	   s==1{print "#define", $$1, "@PNG_PREFIX@" $$1}\
+	   s==2{print "#define @PNG_PREFIX@png_" $$1, "PNG_" $$1}\
+	   END{print prev}' s=0 pnglibconf.out s=1 scripts/prefix.out\
+	   s=2 ${srcdir}/scripts/macro.lst >pnglibconf.tf8
+	mv pnglibconf.tf8 $@
+
+pngprefix.h: scripts/intprefix.out
+	rm -f pngprefix.tf1
+	$(AWK) '{print "#define", $$1, "@PNG_PREFIX@" $$1}' $? >pngprefix.tf1
+	mv pngprefix.tf1 $@
+else
+pnglibconf.h: pnglibconf.out
+	rm -f $@
+	cp $? $@
+
+pngprefix.h: # is empty
+	:>$@
+endif
+
+$(srcdir)/scripts/pnglibconf.h.prebuilt:
+	@echo "Attempting to build $@" >&2
+	@echo "This is a machine generated file, but if you want to make" >&2
+	@echo "a new one simply make 'scripts/pnglibconf.out' and copy that" >&2
+	@exit 1
+
+# The following is necessary to ensure that the local pnglibconf.h is used, not
+# an installed one (this can happen immediately after on a clean system if
+# 'make test' is the first thing the user does.)
+contrib/libtests/pngstest.o contrib/libtests/pngvalid.o pngtest.o: pnglibconf.h
+contrib/libtests/pngunknown.o: pnglibconf.h
+
+# We must use -DPNG_NO_USE_READ_MACROS here even when the library may actually
+# be built with PNG_USE_READ_MACROS; this prevents the read macros from
+# interfering with the symbol file format.
+SYMBOL_CFLAGS = -DPNGLIB_LIBNAME='PNG@PNGLIB_MAJOR@@PNGLIB_MINOR@_0'\
+		-DPNGLIB_VERSION='@PNGLIB_VERSION@'\
+		-DSYMBOL_PREFIX='$(SYMBOL_PREFIX)'\
+		-DPNG_NO_USE_READ_MACROS -DPNG_BUILDING_SYMBOL_TABLE
+
+if DO_PNG_PREFIX
+SYMBOL_CFLAGS += -DPNG_PREFIX='@PNG_PREFIX@'
+endif
+
+.dfn.out:
+	rm -f $@ $*.c $*.tf[12]
+	test -d scripts || mkdir scripts
+	echo '#include "$<"' >$*.c
+	$(DFNCPP) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES)\
+	    $(CPPFLAGS) $(SYMBOL_CFLAGS) $*.c > $*.tf1
+	$(AWK) -f "${srcdir}/scripts/dfn.awk" out="$*.tf2" $*.tf1 1>&2
+	rm -f $*.c $*.tf1
+	mv $*.tf2 $@
+
+# The .dfn file for pnglibconf.h is machine generated
+pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk pngconf.h pngusr.dfa $(DFA_XTRA)
+	rm -f $@ $*.tf[45]
+	$(AWK) -f ${srcdir}/scripts/options.awk out=$*.tf4 version=search\
+	    ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
+	    ${srcdir}/pngusr.dfa $(DFA_XTRA) 1>&2
+	$(AWK) -f ${srcdir}/scripts/options.awk out=$*.tf5 $*.tf4 1>&2
+	rm $*.tf4
+	mv $*.tf5 $@
+
+# Symbol checks (.def and .out files should match)
+scripts/symbols.chk: scripts/checksym.awk scripts/symbols.def scripts/symbols.out
+
+.out.chk:
+	rm -f $@ $*.new
+	$(AWK) -f ${srcdir}/scripts/checksym.awk ${srcdir}/scripts/${*F}.def\
+	    of="$*.new" $< >&2
+	mv $*.new $@
+
+# used on demand to regenerate the standard header, CPPFLAGS should
+# be empty - no non-standard defines
+scripts/pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk pngconf.h
+	rm -f $@ pnglibconf.tf[67]
+	test -z "$(CPPFLAGS)"
+	echo "com @PNGLIB_VERSION@ STANDARD API DEFINITION" |\
+	$(AWK) -f ${srcdir}/scripts/options.awk out=pnglibconf.tf6\
+	    logunsupported=1 version=search ${srcdir}/pngconf.h -\
+	    ${srcdir}/scripts/pnglibconf.dfa 1>&2
+	$(AWK) -f ${srcdir}/scripts/options.awk out=pnglibconf.tf7\
+	    pnglibconf.tf6 1>&2
+	rm pnglibconf.tf6
+	mv pnglibconf.tf7 $@
+
+$(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS): png.h pngconf.h \
+	pnglibconf.h pngpriv.h pngdebug.h pnginfo.h pngstruct.h pngprefix.h
+
+test: check-am
+
+# Extra checks
+check: scripts/symbols.chk
+
+# Don't distribute the generated script files
+dist-hook:
+	cd '$(top_distdir)'; rm -f $(SCRIPT_CLEANFILES)
 
 # install the .../include headers as links to the new ones
 install-data-hook:
-	cd $(DESTDIR)$(includedir); rm -f png.h pngconf.h
-	cd $(DESTDIR)$(includedir); $(LN_S) $(PNGLIB_BASENAME)/png.h png.h
-	cd $(DESTDIR)$(includedir); $(LN_S) $(PNGLIB_BASENAME)/pngconf.h pngconf.h
-	cd $(DESTDIR)$(pkgconfigdir); rm -f libpng.pc
-	cd $(DESTDIR)$(pkgconfigdir); $(LN_S) $(PNGLIB_BASENAME).pc libpng.pc
+	cd '$(DESTDIR)$(includedir)'; rm -f png.h pngconf.h pnglibconf.h
+	cd '$(DESTDIR)$(includedir)'; $(LN_S) $(PNGLIB_BASENAME)/png.h png.h
+	cd '$(DESTDIR)$(includedir)'; $(LN_S) $(PNGLIB_BASENAME)/pngconf.h \
+		pngconf.h
+	cd '$(DESTDIR)$(includedir)'; $(LN_S) $(PNGLIB_BASENAME)/pnglibconf.h \
+		pnglibconf.h
+	cd '$(DESTDIR)$(pkgconfigdir)'; rm -f libpng.pc
+	cd '$(DESTDIR)$(pkgconfigdir)'; $(LN_S) $(PNGLIB_BASENAME).pc libpng.pc
 
-# do evil things to libpng to cause libpng12 to be used, if
-# the compat library is not being built do nothing.
+# do evil things to libpng to cause libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@ to be used
 install-exec-hook:
-	cd $(DESTDIR)$(bindir); rm -f libpng-config
-	cd $(DESTDIR)$(bindir); $(LN_S) $(PNGLIB_BASENAME)-config libpng-config
-	@if test -n "@compatlib@"; then\
-		set -x;\
-		cd $(DESTDIR)$(libdir);\
-		for ext in a la so; do\
+	cd '$(DESTDIR)$(bindir)'; rm -f libpng-config
+	cd '$(DESTDIR)$(bindir)';\
+	   $(LN_S) $(PNGLIB_BASENAME)-config libpng-config
+	@set -x;\
+	cd '$(DESTDIR)$(libdir)';\
+	for ext in a la so so.@PNGLIB_MAJOR@@PNGLIB_MINOR@.@PNGLIB_RELEASE@\
+	   sl dylib dll.a; do\
 		rm -f libpng.$$ext;\
+                if test -f $(PNGLIB_BASENAME).$$ext; then\
                        $(LN_S) $(PNGLIB_BASENAME).$$ext libpng.$$ext;\
-		done;\
-	fi
+                fi;\
+	done
 
 uninstall-hook:
-	cd $(DESTDIR)$(includedir); rm -f png.h pngconf.h
-	rm -f $(DESTDIR)$(pkgconfigdir)/libpng.pc
-	rm -f $(DESTDIR)$(bindir)/libpng-config
-	@if test -n "@compatlib@"; then\
-		set -x;\
-		cd $(DESTDIR)$(libdir);\
-		for ext in a la so; do\
-			rm -f libpng.$$ext;\
-		done;\
-	fi
+	cd '$(DESTDIR)$(includedir)'; rm -f png.h pngconf.h pnglibconf.h
+	rm -f '$(DESTDIR)$(pkgconfigdir)/libpng.pc'
+	rm -f '$(DESTDIR)$(bindir)/libpng-config'
+	rm -f '$(DESTDIR)$(libdir)/libpng.a'
+	rm -f '$(DESTDIR)$(libdir)/libpng.la'
+	rm -f '$(DESTDIR)$(libdir)/libpng.so'
+	rm -f '$(DESTDIR)$(libdir)/libpng.so.@PNGLIB_MAJOR@@PNGLIB_MINOR@.@PNGLIB_RELEASE@'
+	rm -f '$(DESTDIR)$(libdir)/libpng.sl'
+	rm -f '$(DESTDIR)$(libdir)/libpng.dylib'
+	rm -f '$(DESTDIR)$(libdir)/libpng.dll.a'

README

@@ -1,11 +1,11 @@
-README for libpng version 1.2.10rc1 - April 19, 2006 (shared library 12.0)
+README for libpng version 1.7.0alpha10 - February 7, 2013 (shared library 17.0)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.
 
-Libpng comes in several distribution formats.  Get libpng-*.tar.gz
-or libpng-*.tar.bz2 if you want UNIX-style line endings in the text
-files, or lpng*.zip if you want DOS-style line endings.
+Libpng comes in several distribution formats.  Get libpng-*.tar.gz,
+libpng-*.tar.xz or libpng-*.tar.bz2 if you want UNIX-style line endings
+in the text files, or lpng*.zip if you want DOS-style line endings.
 
 Version 0.89 was the first official release of libpng.  Don't let the
 fact that it's the first release fool you.  The libpng library has been in
@@ -54,11 +54,11 @@ to set different actions based on whether the CRC error occurred in a
 critical or an ancillary chunk.
 
 The changes made to the library, and bugs fixed are based on discussions
-on the PNG-implement mailing list
-and not on material submitted privately to Guy, Andreas, or Glenn.  They will
-forward any good suggestions to the list.
+on the PNG-implement mailing list and not on material submitted
+privately to Guy, Andreas, or Glenn.  They will forward any good
+suggestions to the list.
 
-For a detailed description on using libpng, read libpng.txt.  For
+For a detailed description on using libpng, read libpng-manual.txt.  For
 examples of libpng in a program, see example.c and pngtest.c.  For usage
 information and restrictions (what little they are) on libpng, see
 png.h.  For a description on using zlib (the compression library used by
@@ -101,31 +101,29 @@ Finally, if you get any warning messages when compiling libpng
 fix.  Please mention "libpng" somewhere in the subject line.  Thanks.
 
 This release was created and will be supported by myself (of course
-based in a large way on Guy's and Andreas' earlier work), and the PNG group.
+based in a large way on Guy's and Andreas' earlier work), and the PNG
+development group.
 
-Send comments/corrections/commendations to png-mng-implement at lists.sf.net
-(subscription required; visit 
+Send comments/corrections/commendations to png-mng-implement at
+lists.sourceforge.net (subscription required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement
 to subscribe) or to glennrp at users.sourceforge.net
 
 You can't reach Guy, the original libpng author, at the addresses
-given in previous versions of this document.  He and Andreas will read mail
-addressed to the png-implement list, however.
+given in previous versions of this document.  He and Andreas will
+read mail addressed to the png-implement list, however.
 
 Please do not send general questions about PNG.  Send them to
-the (png-list at ccrc.wustl.edu, subscription required, write to
-majordomo at ccrc.wustl.edu with "subscribe png-list" in your message).
-On the other hand,
-please do not send libpng questions to that address, send them to me
-or to the png-implement list.  I'll
-get them in the end anyway.  If you have a question about something
+png-mng-misc at lists.sf.net (subscription required; visit
+https://lists.sourceforge.net/lists/listinfo/png-mng-misc to
+subscribe).  If you have a question about something
 in the PNG specification that is related to using libpng, send it
 to me.  Send me any questions that start with "I was using libpng,
 and ...".  If in doubt, send questions to me.  I'll bounce them
 to others, if necessary.
 
 Please do not send suggestions on how to change PNG.  We have
-been discussing PNG for nine years now, and it is official and
+been discussing PNG for sixteen years now, and it is official and
 finished.  If you have suggestions for libpng, however, I'll
 gladly listen.  Even if your suggestion is not used immediately,
 it may be used later.
@@ -140,14 +138,17 @@ Files in this distribution:
       TODO          =>  Things not implemented in the current library
       Y2KINFO       =>  Statement of Y2K compliance
       example.c     =>  Example code for using libpng functions
-      libpng.3      =>  manual page for libpng (includes libpng.txt)
-      libpng.txt    =>  Description of libpng and its functions
+      libpng.3      =>  manual page for libpng (includes libpng-manual.txt)
+      libpng-manual.txt  =>  Description of libpng and its functions
       libpngpf.3    =>  manual page for libpng's private functions
       png.5         =>  manual page for the PNG format
       png.c         =>  Basic interface functions common to library
-      png.h         =>  Library function and interface declarations
-      pngconf.h     =>  System specific library configuration
-      pngasmrd.h    =>  Header file for assembler-coded functions
+      png.h         =>  Library function and interface declarations (public)
+      pngpriv.h     =>  Library function and interface declarations (private)
+      pngconf.h     =>  System specific library configuration (public)
+      pngstruct.h   =>  png_struct declaration (private)
+      pnginfo.h     =>  png_info struct declaration (private)
+      pngdebug.h    =>  debugging macros (private)
       pngerror.c    =>  Error/warning message I/O functions
       pngget.c      =>  Functions for retrieving info from struct
       pngmem.c      =>  Memory handling functions
@@ -174,84 +175,22 @@ Files in this distribution:
        pngminus     =>  Simple pnm2png and png2pnm programs
        pngsuite     =>  Test images
        visupng      =>  Contains a MSVC workspace for VisualPng
-      projects      =>  Contains project files and workspaces for building DLL
-       beos             =>  Contains a Beos workspace for building libpng
-       c5builder        =>  Contains a Borland workspace for building libpng
-                            and zlib
-       visualc6         =>  Contains a Microsoft Visual C++ (MSVC) workspace
-                            for building libpng and zlib
-       netware.txt      =>  Contains instructions for downloading a set of
-                            project files for building libpng and zlib on
-                            Netware.
-       wince.txt        =>  Contains instructions for downloading a Microsoft
-                            Visual C++ (Windows CD Toolkit) workspace for
-                            building libpng and zlib on WindowsCE
+      projects      =>  Contains project files and workspaces for
+                        building a DLL
+       cbuilder5        =>  Contains a Borland workspace for building
+                            libpng and zlib
+       visualc6         =>  Contains a Microsoft Visual C++ (MSVC)
+                            workspace for building libpng and zlib
+       visualc71        =>  Contains a Microsoft Visual C++ (MSVC)
+                            workspace for building libpng and zlib
+       xcode            =>  Contains an Apple xcode
+                            workspace for building libpng and zlib
       scripts       =>  Directory containing scripts for building libpng:
-       descrip.mms      =>  VMS makefile for MMS or MMK
-       makefile.std     =>  Generic UNIX makefile (cc, creates static libpng.a)
-       makefile.elf     =>  Linux/ELF makefile symbol versioning,
-                            gcc, creates libpng12.so.0.1.2.10rc1)
-       makefile.linux   =>  Linux/ELF makefile
-                            (gcc, creates libpng12.so.0.1.2.10rc1)
-       makefile.gcmmx   =>  Linux/ELF makefile
-                            (gcc, creates libpng12.so.0.1.2.10rc1,
-                            uses assembler code tuned for Intel MMX platform)
-       makefile.gcc     =>  Generic makefile (gcc, creates static libpng.a)
-       makefile.knr     =>  Archaic UNIX Makefile that converts files with
-                            ansi2knr (Requires ansi2knr.c from
-                            ftp://ftp.cs.wisc.edu/ghost)
-       makefile.aix     =>  AIX makefile
-       makefile.cygwin  =>  Cygwin/gcc makefile
-       makefile.darwin  =>  Darwin makefile
-       makefile.dec     =>  DEC Alpha UNIX makefile
-       makefile.freebsd =>  FreeBSD makefile
-       makefile.hpgcc   =>  HPUX makefile using gcc
-       makefile.hpux    =>  HPUX (10.20 and 11.00) makefile
-       makefile.hp64    =>  HPUX (10.20 and 11.00) makefile, 64 bit
-       makefile.ibmc    =>  IBM C/C++ version 3.x for Win32 and OS/2 (static)
-       makefile.intel   =>  Intel C/C++ version 4.0 and later
-       libpng.icc       =>  Project file, IBM VisualAge/C++ 4.0 or later
-       makefile.netbsd  =>  NetBSD/cc makefile, PNGGCCRD, makes libpng.so.
-       makefile.ne12bsd  =>  NetBSD/cc makefile, PNGGCCRD, makes libpng12.so
-       makefile.openbsd =>  OpenBSD makefile
-       makefile.sgi     =>  Silicon Graphics IRIX (cc, creates static lib)
-       makefile.sggcc   =>  Silicon Graphics
-                            (gcc, creates libpng12.so.0.1.2.10rc1)
-       makefile.sunos   =>  Sun makefile
-       makefile.solaris =>  Solaris 2.X makefile
-                            (gcc, creates libpng12.so.0.1.2.10rc1)
-       makefile.so9     =>  Solaris 9 makefile
-                            (gcc, creates libpng12.so.0.1.2.10rc1)
-       makefile.32sunu  =>  Sun Ultra 32-bit makefile
-       makefile.64sunu  =>  Sun Ultra 64-bit makefile
-       makefile.sco     =>  For SCO OSr5  ELF and Unixware 7 with Native cc
-       makefile.mips    =>  MIPS makefile
-       makefile.acorn   =>  Acorn makefile
-       makefile.amiga   =>  Amiga makefile
-       smakefile.ppc    =>  AMIGA smakefile for SAS C V6.58/7.00 PPC
-                            compiler (Requires SCOPTIONS, copied from
-                            scripts/SCOPTIONS.ppc)
-       makefile.atari   =>  Atari makefile
-       makefile.beos    =>  BEOS makefile for X86
-       makefile.bor     =>  Borland makefile (uses bcc)
-       makefile.bc32    =>  32-bit Borland C++ (all modules compiled in C mode)
-       makefile.tc3     =>  Turbo C 3.0 makefile
-       makefile.dj2     =>  DJGPP 2 makefile
-       makefile.msc     =>  Microsoft C makefile
-       makefile.vcawin32=>  makefile for Microsoft Visual C++ 5.0 and
-                            later (uses assembler code tuned for Intel MMX
-                            platform)
-       makefile.vcwin32 =>  makefile for Microsoft Visual C++ 4.0 and
-                            later (does not use assembler code)
-       makefile.os2     =>  OS/2 Makefile (gcc and emx, requires pngos2.def)
-       pngos2.def       =>  OS/2 module definition file used by makefile.os2
-       makefile.watcom  =>  Watcom 10a+ Makefile, 32-bit flat memory model
-       makevms.com      =>  VMS build script
-       SCOPTIONS.ppc    =>  Used with smakefile.ppc
+                            (see scripts/README.txt for the list of scripts)
 
 Good luck, and happy coding.
 
--Glenn Randers-Pehrson (current maintainer)
+-Glenn Randers-Pehrson (current maintainer, since 1998)
  Internet: glennrp at users.sourceforge.net
 
 -Andreas Eric Dilger (former maintainer, 1996-1997)

TODO

@@ -1,12 +1,11 @@
+/*
 TODO - list of things to do for libpng:
 
 Final bug fixes.
-Improve API by hiding the png_struct and png_info structs.
-Finish work on the no-floating-point version (including gamma compensation)
 Better C++ wrapper/full C++ implementation?
 Fix problem with C++ and EXTERN "C".
 cHRM transformation.
-Improve setjmp/longjmp usage or remove it in favor of returning error codes.
+Remove setjmp/longjmp usage in favor of returning error codes.
 Add "grayscale->palette" transformation and "palette->grayscale" detection.
 Improved dithering.
 Multi-lingual error and warning message support.
@@ -17,8 +16,12 @@ Better filter selection
    (counting huffman bits/precompression?  filter inertia?  filter costs?).
 Histogram creation.
 Text conversion between different code pages (Latin-1 -> Mac and DOS).
-Should we always malloc 2^bit_depth PLTE/tRNS/hIST entries for safety?
-Build gamma tables using fixed point (and do away with floating point entirely).
+Avoid building gamma tables whenever possible.
 Use greater precision when changing to linear gamma for compositing against
   background and doing rgb-to-gray transformation.
 Investigate pre-incremented loop counters and other loop constructions.
+Add interpolated method of handling interlacing.
+Switch to the simpler zlib (zlib/libpng) license if legally possible.
+Extend pngvalid.c to validate more of the libpng transformations.
+
+*/

Y2KINFO

@@ -1,55 +0,0 @@
-   Y2K compliance in libpng:
-   =========================
-
-      April 19, 2006
-
-      Since the PNG Development group is an ad-hoc body, we can't make
-      an official declaration.
-
-      This is your unofficial assurance that libpng from version 0.71 and
-      upward through 1.2.10rc1 are Y2K compliant.  It is my belief that earlier
-      versions were also Y2K compliant.
-
-      Libpng only has three year fields.  One is a 2-byte unsigned integer
-      that will hold years up to 65535.  The other two hold the date in text
-      format, and will hold years up to 9999.
-
-      The integer is
-          "png_uint_16 year" in png_time_struct.
-
-      The strings are
-          "png_charp time_buffer" in png_struct and
-          "near_time_buffer", which is a local character string in png.c.
-
-      There are seven time-related functions:
-
-          png_convert_to_rfc_1123() in png.c
-            (formerly png_convert_to_rfc_1152() in error)
-          png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
-          png_convert_from_time_t() in pngwrite.c
-          png_get_tIME() in pngget.c
-          png_handle_tIME() in pngrutil.c, called in pngread.c
-          png_set_tIME() in pngset.c
-          png_write_tIME() in pngwutil.c, called in pngwrite.c
-
-      All appear to handle dates properly in a Y2K environment.  The
-      png_convert_from_time_t() function calls gmtime() to convert from system
-      clock time, which returns (year - 1900), which we properly convert to
-      the full 4-digit year.  There is a possibility that applications using
-      libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
-      function, or that they are incorrectly passing only a 2-digit year
-      instead of "year - 1900" into the png_convert_from_struct_tm() function,
-      but this is not under our control.  The libpng documentation has always
-      stated that it works with 4-digit years, and the APIs have been
-      documented as such.
-
-      The tIME chunk itself is also Y2K compliant.  It uses a 2-byte unsigned
-      integer to hold the year, and can hold years as large as 65535.
-
-      zlib, upon which libpng depends, is also Y2K compliant.  It contains
-      no date-related code.
-
-
-         Glenn Randers-Pehrson
-         libpng maintainer
-         PNG Development Group

arm/arm_init.c

@@ -0,0 +1,86 @@
+
+/* arm_init.c - NEON optimised filter functions
+ *
+ * Copyright (c) 2012 Glenn Randers-Pehrson
+ * Written by Mans Rullgard, 2011.
+ * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+#include "../pngpriv.h"
+
+/* __arm__ is defined by GCC, MSVC defines _M_ARM to the ARM version number */
+#if defined __linux__ && defined __arm__
+#include <stdio.h>
+#include <elf.h>
+#include <asm/hwcap.h>
+
+static int png_have_hwcap(unsigned cap)
+{
+   FILE *f = fopen("/proc/self/auxv", "r");
+   Elf32_auxv_t aux;
+   int have_cap = 0;
+
+   if (!f)
+      return 0;
+
+   while (fread(&aux, sizeof(aux), 1, f) > 0)
+   {
+      if (aux.a_type == AT_HWCAP &&
+          aux.a_un.a_val & cap)
+      {
+         have_cap = 1;
+         break;
+      }
+   }
+
+   fclose(f);
+
+   return have_cap;
+}
+#endif /* __linux__ && __arm__ */
+
+void
+png_init_filter_functions_neon(png_structrp pp, unsigned int bpp)
+{
+#ifdef __arm__
+#ifdef __linux__
+   if (!png_have_hwcap(HWCAP_NEON))
+      return;
+#endif
+
+   /* IMPORTANT: any new external functions used here must be declared using
+    * PNG_INTERNAL_FUNCTION in ../pngpriv.h.  This is required so that the
+    * 'prefix' option to configure works:
+    *
+    *    ./configure --with-libpng-prefix=foobar_
+    *
+    * Verify you have got this right by running the above command, doing a build
+    * and examining pngprefix.h; it must contain a #define for every external
+    * function you add.  (Notice that this happens automatically for the
+    * initialization function.)
+    */
+   pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_neon;
+
+   if (bpp == 3)
+   {
+      pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_neon;
+      pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_neon;
+      pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
+         png_read_filter_row_paeth3_neon;
+   }
+
+   else if (bpp == 4)
+   {
+      pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_neon;
+      pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_neon;
+      pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
+          png_read_filter_row_paeth4_neon;
+   }
+#else
+   PNG_UNUSED(pp)
+   PNG_UNUSED(bpp)
+#endif
+}

arm/filter_neon.S

@@ -0,0 +1,232 @@
+
+/* filter_neon.S - NEON optimised filter functions
+ *
+ * Copyright (c) 2011 Glenn Randers-Pehrson
+ * Written by Mans Rullgard, 2011.
+ * Last changed in libpng 1.5.7 [December 15, 2011]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+/* This is required to get the symbol renames, which are #defines */
+#define PNG_VERSION_INFO_ONLY
+#include "../pngpriv.h"
+
+#ifdef __arm__
+#if defined(__linux__) && defined(__ELF__)
+.section .note.GNU-stack,"",%progbits /* mark stack as non-executable */
+#endif
+
+#ifdef __ELF__
+#   define ELF
+#else
+#   define ELF @
+#endif
+
+        .arch armv7-a
+        .fpu  neon
+
+.macro  func    name, export=0
+    .macro endfunc
+ELF     .size   \name, . - \name
+        .endfunc
+        .purgem endfunc
+    .endm
+        .text
+    .if \export
+        .global \name
+    .endif
+ELF     .type   \name, STT_FUNC
+        .func   \name
+\name:
+.endm
+
+func    png_read_filter_row_sub4_neon, export=1
+        ldr             r3,  [r0, #4]           @ rowbytes
+        vmov.i8         d3,  #0
+1:
+        vld4.32         {d4[],d5[],d6[],d7[]},    [r1,:128]
+        vadd.u8         d0,  d3,  d4
+        vadd.u8         d1,  d0,  d5
+        vadd.u8         d2,  d1,  d6
+        vadd.u8         d3,  d2,  d7
+        vst4.32         {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
+        subs            r3,  r3,  #16
+        bgt             1b
+
+        bx              lr
+endfunc
+
+func    png_read_filter_row_sub3_neon, export=1
+        ldr             r3,  [r0, #4]           @ rowbytes
+        vmov.i8         d3,  #0
+        mov             r0,  r1
+        mov             r2,  #3
+        mov             r12, #12
+        vld1.8          {q11},    [r0], r12
+1:
+        vext.8          d5,  d22, d23, #3
+        vadd.u8         d0,  d3,  d22
+        vext.8          d6,  d22, d23, #6
+        vadd.u8         d1,  d0,  d5
+        vext.8          d7,  d23, d23, #1
+        vld1.8          {q11},    [r0], r12
+        vst1.32         {d0[0]},  [r1,:32], r2
+        vadd.u8         d2,  d1,  d6
+        vst1.32         {d1[0]},  [r1], r2
+        vadd.u8         d3,  d2,  d7
+        vst1.32         {d2[0]},  [r1], r2
+        vst1.32         {d3[0]},  [r1], r2
+        subs            r3,  r3,  #12
+        bgt             1b
+
+        bx              lr
+endfunc
+
+func    png_read_filter_row_up_neon, export=1
+        ldr             r3,  [r0, #4]           @ rowbytes
+1:
+        vld1.8          {q0}, [r1,:128]
+        vld1.8          {q1}, [r2,:128]!
+        vadd.u8         q0,  q0,  q1
+        vst1.8          {q0}, [r1,:128]!
+        subs            r3,  r3,  #16
+        bgt             1b
+
+        bx              lr
+endfunc
+
+func    png_read_filter_row_avg4_neon, export=1
+        ldr             r12, [r0, #4]           @ rowbytes
+        vmov.i8         d3,  #0
+1:
+        vld4.32         {d4[],d5[],d6[],d7[]},    [r1,:128]
+        vld4.32         {d16[],d17[],d18[],d19[]},[r2,:128]!
+        vhadd.u8        d0,  d3,  d16
+        vadd.u8         d0,  d0,  d4
+        vhadd.u8        d1,  d0,  d17
+        vadd.u8         d1,  d1,  d5
+        vhadd.u8        d2,  d1,  d18
+        vadd.u8         d2,  d2,  d6
+        vhadd.u8        d3,  d2,  d19
+        vadd.u8         d3,  d3,  d7
+        vst4.32         {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
+        subs            r12, r12, #16
+        bgt             1b
+
+        bx              lr
+endfunc
+
+func    png_read_filter_row_avg3_neon, export=1
+        push            {r4,lr}
+        ldr             r12, [r0, #4]           @ rowbytes
+        vmov.i8         d3,  #0
+        mov             r0,  r1
+        mov             r4,  #3
+        mov             lr,  #12
+        vld1.8          {q11},    [r0], lr
+1:
+        vld1.8          {q10},    [r2], lr
+        vext.8          d5,  d22, d23, #3
+        vhadd.u8        d0,  d3,  d20
+        vext.8          d17, d20, d21, #3
+        vadd.u8         d0,  d0,  d22
+        vext.8          d6,  d22, d23, #6
+        vhadd.u8        d1,  d0,  d17
+        vext.8          d18, d20, d21, #6
+        vadd.u8         d1,  d1,  d5
+        vext.8          d7,  d23, d23, #1
+        vld1.8          {q11},    [r0], lr
+        vst1.32         {d0[0]},  [r1,:32], r4
+        vhadd.u8        d2,  d1,  d18
+        vst1.32         {d1[0]},  [r1], r4
+        vext.8          d19, d21, d21, #1
+        vadd.u8         d2,  d2,  d6
+        vhadd.u8        d3,  d2,  d19
+        vst1.32         {d2[0]},  [r1], r4
+        vadd.u8         d3,  d3,  d7
+        vst1.32         {d3[0]},  [r1], r4
+        subs            r12, r12, #12
+        bgt             1b
+
+        pop             {r4,pc}
+endfunc
+
+.macro  paeth           rx,  ra,  rb,  rc
+        vaddl.u8        q12, \ra, \rb           @ a + b
+        vaddl.u8        q15, \rc, \rc           @ 2*c
+        vabdl.u8        q13, \rb, \rc           @ pa
+        vabdl.u8        q14, \ra, \rc           @ pb
+        vabd.u16        q15, q12, q15           @ pc
+        vcle.u16        q12, q13, q14           @ pa <= pb
+        vcle.u16        q13, q13, q15           @ pa <= pc
+        vcle.u16        q14, q14, q15           @ pb <= pc
+        vand            q12, q12, q13           @ pa <= pb && pa <= pc
+        vmovn.u16       d28, q14
+        vmovn.u16       \rx, q12
+        vbsl            d28, \rb, \rc
+        vbsl            \rx, \ra, d28
+.endm
+
+func    png_read_filter_row_paeth4_neon, export=1
+        ldr             r12, [r0, #4]           @ rowbytes
+        vmov.i8         d3,  #0
+        vmov.i8         d20, #0
+1:
+        vld4.32         {d4[],d5[],d6[],d7[]},    [r1,:128]
+        vld4.32         {d16[],d17[],d18[],d19[]},[r2,:128]!
+        paeth           d0,  d3,  d16, d20
+        vadd.u8         d0,  d0,  d4
+        paeth           d1,  d0,  d17, d16
+        vadd.u8         d1,  d1,  d5
+        paeth           d2,  d1,  d18, d17
+        vadd.u8         d2,  d2,  d6
+        paeth           d3,  d2,  d19, d18
+        vmov            d20, d19
+        vadd.u8         d3,  d3,  d7
+        vst4.32         {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
+        subs            r12, r12, #16
+        bgt             1b
+
+        bx              lr
+endfunc
+
+func    png_read_filter_row_paeth3_neon, export=1
+        push            {r4,lr}
+        ldr             r12, [r0, #4]           @ rowbytes
+        vmov.i8         d3,  #0
+        vmov.i8         d4,  #0
+        mov             r0,  r1
+        mov             r4,  #3
+        mov             lr,  #12
+        vld1.8          {q11},    [r0], lr
+1:
+        vld1.8          {q10},    [r2], lr
+        paeth           d0,  d3,  d20, d4
+        vext.8          d5,  d22, d23, #3
+        vadd.u8         d0,  d0,  d22
+        vext.8          d17, d20, d21, #3
+        paeth           d1,  d0,  d17, d20
+        vst1.32         {d0[0]},  [r1,:32], r4
+        vext.8          d6,  d22, d23, #6
+        vadd.u8         d1,  d1,  d5
+        vext.8          d18, d20, d21, #6
+        paeth           d2,  d1,  d18, d17
+        vext.8          d7,  d23, d23, #1
+        vld1.8          {q11},    [r0], lr
+        vst1.32         {d1[0]},  [r1], r4
+        vadd.u8         d2,  d2,  d6
+        vext.8          d19, d21, d21, #1
+        paeth           d3,  d2,  d19, d18
+        vst1.32         {d2[0]},  [r1], r4
+        vmov            d4,  d19
+        vadd.u8         d3,  d3,  d7
+        vst1.32         {d3[0]},  [r1], r4
+        subs            r12, r12, #12
+        bgt             1b
+
+        pop             {r4,pc}
+endfunc
+#endif

autogen.sh

@@ -1,24 +1,219 @@
 #! /bin/sh
-# a quick hack script to generate necessary files from 
-# auto* tools.
 #
-# WARNING: if you run this you will change the versions
-# of the tools which are used and, maybe, required!
-{
-	echo "running libtoolize" >&2
-	libtoolize --copy --automake
-} && {
-	echo "running aclocal" >&2
-	aclocal
-} && {
-	echo "running autoheader [ignore the warnings]" >&2
-	autoheader
-} && {
-	echo "running automake" >&2
-	automake --foreign -a -c
-} && {
-	echo "running autoconf" >&2
-	autoconf
-} &&
-	echo "autogen complete" >&2 ||
-	echo "ERROR: autogen.sh failed, autogen is incomplete" >&2
+# Run 'autoreconf' to build 'configure', 'Makefile.in' and other configure
+# control files.
+#
+# The first time this is run on a GIT checkout the only files that exist are
+# configure.ac and Makefile.am; all of the autotools support scripts are
+# missing.  They are instantiated with autoreconf --force --install.
+#
+# For regular ("tarball") distributions all the files should exist.  We do not
+# want them to be updated *under any circumstances*.  It should never be
+# necessary to rune autogen.sh because ./configure --enable-maintainer-mode says
+# what to do if Makeile.am or configure.ac are changed.
+#
+# It is *probably* OK to update the files on a GIT checkout, because they have
+# come from the local tools, but leave that to the user who is assumed to know
+# whether it is ok or required.
+#
+# This script is intended to work without arguments, there are, however, hidden
+# arguments for (a) use while testing the script and (b) to fix up systems that
+# have been broken.  If (b) is required the script prompts for the correct
+# options.  For this reason the options are *NOT* documented in the help; this
+# is deliberate; UTSL.
+#
+clean=
+maintainer=
+while test $# -gt 0
+do
+   case "$1" in
+      --maintainer)
+         maintainer=1;;
+
+      --clean)
+         clean=1;;
+
+      *)
+         exec >&2
+         echo "$0: usage: ./autogen.sh"
+         if test -d .git
+         then
+            echo "  ./autogen.sh generates the configure script and"
+            echo "  Makefile.in, or refreshes them after changes to Makefile.am"
+            echo "  or configure.ac.  You may prefer to just run autoreconf."
+         elif test -z "$maintainer"
+         then
+            echo "  DO NOT RUN THIS SCRIPT."
+            echo "  If you need to change Makefile.am or configure.ac then you"
+            echo "  also need to run ./configure --enable-maintainer-mode and"
+            echo "  use the appropriate autotools, *NOT* this script, to update"
+            echo "  everything, please check the documentation of autoreconf."
+            echo "  WARNING: libpng is intentionally generated with a known,"
+            echo "  fixed, set of autotools.  It is known *NOT* to work with"
+            echo "  the collection of autotools distributed on highly reputable"
+            echo "  operating systems."
+            echo "  Remember: autotools is GNU software, you are expected to"
+            echo "  pay for support."
+         else
+            echo "  You have run autogen.sh with --maintainer enabled and you"
+            echo "  are not using a GIT distribution, then you have given an"
+            echo "  unrecognized argument.  This is not good. --maintainer"
+            echo "  switches off any assumptions that you might not know what"
+            echo "  you are doing."
+         fi
+         exit 1;;
+   esac
+
+   shift
+done
+#
+# First check for a set of the autotools files; if absent then this is assumed
+# to be a GIT version and the local autotools must be used.  If present this
+# is a tarball distribution and the script should not be used.  If partially
+# present bad things are happening.
+#
+# The autotools generated files:
+libpng_autotools_files="Makefile.in aclocal.m4 config.guess config.h.in\
+   config.sub configure depcomp install-sh ltmain.sh missing test-driver"
+#
+# These are separate because 'maintainer-clean' does not remove them.
+libpng_libtool_files="scripts/libtool.m4 scripts/ltoptions.m4\
+   scripts/ltsugar.m4 scripts/ltversion.m4 scripts/lt~obsolete.m4"
+
+libpng_autotools_dirs="autom4te.cache" # not required
+#
+# The configure generated files:
+libpng_configure_files="Makefile config.h config.log config.status\
+   libpng-config libpng.pc libtool stamp-h1"
+
+libpng_configure_dirs=".deps"
+#
+# We must remove the configure generated files as well as the autotools
+# generated files if autotools are regenerated because otherwise if configure
+# has been run without "--enable-maintainer-mode" make can do a partial update
+# of Makefile.  These functions do the two bits of cleaning.
+clean_autotools(){
+   rm -rf $libpng_autotools_files $libpng_libtool_files $libpng_autotools_dirs
+}
+
+clean_configure(){
+   rm -rf $libpng_configure_files $libpng_configure_dirs
+}
+#
+# Clean: remove everything (this is to help with testing)
+if test -n "$clean"
+then
+   clean_configure
+   if test -n "$maintainer"
+   then
+      clean_autotools
+   fi
+
+   exit 0
+fi
+#
+# Validate the distribution.
+libpng_autotools_file_found=
+libpng_autotools_file_missing=
+for file in $libpng_autotools_files
+do
+   if test -f  "$file"
+   then
+      libpng_autotools_file_found=1
+   else
+      libpng_autotools_file_missing=1
+   fi
+done
+#
+# Presence of one of these does not *invalidate* missing, but absence
+# invalidates found.
+for file in $libpng_libtool_files
+do
+   if test ! -f "$file"
+   then
+      libpng_autotools_file_missing=1
+   fi
+done
+#
+# The cache directory doesn't matter - it will be regenerated and does not exist
+# anyway in a tarball.
+#
+# Either everything is missing or everything is there, the --maintainer option
+# just changes this so that the mode is set to generate all the files.
+mode=
+if test -z "$libpng_autotools_file_found" -o -n "$maintainer"
+then
+   mode="autoreconf"
+else
+   if test -n "$libpng_autotools_file_missing"
+   then
+      mode="broken"
+   else
+      mode="configure"
+   fi
+fi
+#
+# So:
+case "$mode" in
+   autoreconf)
+      # Clean in case configure files exist
+      clean_configure
+      clean_autotools
+      # Everything must be initialized, so use --force
+      if autoreconf --warnings=all --force --install
+      then
+         missing=
+         for file in $libpng_autotools_files
+         do
+            test -f "$file" || missing=1
+         done
+         # ignore the cache directory
+         test -z "$missing" || {
+            exec >&2
+            echo "autoreconf was run, but did not produce all the expected"
+            echo "files.  It is likely that your autotools installation is"
+            echo "not compatible with that expected by libpng."
+            exit 1
+         }
+      else
+         exec >&2
+         echo "autoreconf failed: your version of autotools is incompatible"
+         echo "with this libpng version.  Please use a distributed archive"
+         echo "(which includes the autotools generated files) and run configure"
+         echo "instead."
+         exit 1
+      fi;;
+
+   configure)
+      if test -d .git
+      then
+         exec >&2
+         echo "ERROR: running autoreconf on an initialized sytem"
+         echo "  This is not necessary; it is only necessary to remake the"
+         echo "  autotools generated files if Makefile.am or configure.ac"
+         echo "  change and make does the right thing with:"
+         echo
+         echo "     ./configure --enable-maintainer-mode."
+         echo
+         echo "  You can run autoreconf yourself if you don't like maintainer"
+         echo "  mode and you can also just run autoreconf -f -i to initialize"
+         echo "  everything in the first place; this script is only for"
+         echo "  compatiblity with prior releases."
+         exit 1
+      else
+         exec >&2
+         echo "autogen.sh is intended only to generate 'configure' on systems"
+         echo "that do not have it.  You have a complete 'configure', if you"
+         echo "need to change Makefile.am or configure.ac you also need to"
+         echo "run configure with the --enable-maintainer-mode option."
+         exit 1
+      fi;;
+
+   broken)
+      exec >&2
+      echo "Your system has a partial set of autotools generated files."
+      echo "autogen.sh is unable to proceed.  The full set of files is"
+      echo "contained in the libpng 'tar' distribution archive and you do"
+      echo "not need to run autogen.sh if you use it."
+      exit 1;;
+esac

config.h.in

@@ -1,86 +0,0 @@
-/* config.h.in.  Generated from configure.ac by autoheader.  */
-
-/* Define to 1 if you have the <dlfcn.h> header file. */
-#undef HAVE_DLFCN_H
-
-/* Define to 1 if you have the <inttypes.h> header file. */
-#undef HAVE_INTTYPES_H
-
-/* Define to 1 if you have the `m' library (-lm). */
-#undef HAVE_LIBM
-
-/* Define to 1 if you have the `z' library (-lz). */
-#undef HAVE_LIBZ
-
-/* Define to 1 if your system has a GNU libc compatible `malloc' function, and
-   to 0 otherwise. */
-#undef HAVE_MALLOC
-
-/* Define to 1 if you have the <malloc.h> header file. */
-#undef HAVE_MALLOC_H
-
-/* Define to 1 if you have the <memory.h> header file. */
-#undef HAVE_MEMORY_H
-
-/* Define to 1 if you have the `memset' function. */
-#undef HAVE_MEMSET
-
-/* Define to 1 if you have the `pow' function. */
-#undef HAVE_POW
-
-/* Define to 1 if you have the <stdint.h> header file. */
-#undef HAVE_STDINT_H
-
-/* Define to 1 if you have the <stdlib.h> header file. */
-#undef HAVE_STDLIB_H
-
-/* Define to 1 if you have the <strings.h> header file. */
-#undef HAVE_STRINGS_H
-
-/* Define to 1 if you have the <string.h> header file. */
-#undef HAVE_STRING_H
-
-/* Define to 1 if you have the <sys/stat.h> header file. */
-#undef HAVE_SYS_STAT_H
-
-/* Define to 1 if you have the <sys/types.h> header file. */
-#undef HAVE_SYS_TYPES_H
-
-/* Define to 1 if you have the <unistd.h> header file. */
-#undef HAVE_UNISTD_H
-
-/* Name of package */
-#undef PACKAGE
-
-/* Define to the address where bug reports for this package should be sent. */
-#undef PACKAGE_BUGREPORT
-
-/* Define to the full name of this package. */
-#undef PACKAGE_NAME
-
-/* Define to the full name and version of this package. */
-#undef PACKAGE_STRING
-
-/* Define to the one symbol short name of this package. */
-#undef PACKAGE_TARNAME
-
-/* Define to the version of this package. */
-#undef PACKAGE_VERSION
-
-/* Define to 1 if you have the ANSI C header files. */
-#undef STDC_HEADERS
-
-/* Define to 1 if your <sys/time.h> declares `struct tm'. */
-#undef TM_IN_SYS_TIME
-
-/* Version number of package */
-#undef VERSION
-
-/* Define to empty if `const' does not conform to ANSI C. */
-#undef const
-
-/* Define to rpl_malloc if the replacement function should be used. */
-#undef malloc
-
-/* Define to `unsigned' if <sys/types.h> does not define. */
-#undef size_t

configure.ac

@@ -3,7 +3,7 @@
 dnl Process this file with autoconf to produce a configure script.
 dnl
 dnl Minor upgrades (compatible ABI): increment the package version
-dnl (third field in two places below) and set the PNGLIB_MINOR
+dnl (third field in two places below) and set the PNGLIB_RELEASE
 dnl variable.
 dnl
 dnl Major upgrades (incompatible ABI): increment the package major
@@ -14,123 +14,344 @@ dnl Makefile.am to upgrade the package name.
 dnl This is here to prevent earlier autoconf from being used, it
 dnl should not be necessary to regenerate configure if the time
 dnl stamps are correct
-AC_PREREQ(2.59)
+AC_PREREQ([2.68])
 
 dnl Version number stuff here:
 
-AC_INIT([libpng], [1.2.10rc1], [png-mng-implement@lists.sourceforge.net])
-AM_INIT_AUTOMAKE
-dnl stop configure from automagically running automake
+AC_INIT([libpng],[1.7.0alpha10],[png-mng-implement@lists.sourceforge.net])
+AC_CONFIG_MACRO_DIR([scripts])
+
+# libpng does not follow GNU file name conventions (hence 'foreign')
+# color-tests requires automake 1.11 or later
+# silent-rules requires automake 1.11 or later
+# dist-xz requires automake 1.11 or later
+# 1.12.2 fixes a security issue in 1.11.2 and 1.12.1
+AM_INIT_AUTOMAKE([1.12.2 foreign dist-xz color-tests silent-rules])
+# was:
+# AM_INIT_AUTOMAKE
 AM_MAINTAINER_MODE
 
-PNGLIB_VERSION=1.2.10rc1
-PNGLIB_MAJOR=12
-PNGLIB_MINOR=10
+dnl configure.ac and Makefile.am expect automake 1.11.2 or a compatible later
+dnl version; aclocal.m4 will generate a failure if you use a prior version of
+dnl automake, so the following is not necessary (and is not defined anyway):
+dnl AM_PREREQ([1.11.2])
+dnl stop configure from automagically running automake
+
+PNGLIB_VERSION=1.7.0alpha10
+PNGLIB_MAJOR=1
+PNGLIB_MINOR=7
+PNGLIB_RELEASE=0
 
 dnl End of version number stuff
 
 AC_CONFIG_SRCDIR([pngget.c])
-AM_CONFIG_HEADER([config.h])
+AC_CONFIG_HEADERS([config.h])
 
 # Checks for programs.
+AC_LANG([C])
 AC_PROG_CC
-AC_PROG_LD
+AM_PROG_AS
+LT_PATH_LD
 AC_PROG_CPP
-AC_CHECK_TOOL(SED, sed, :)
+AC_PROG_AWK
 AC_PROG_INSTALL
 AC_PROG_LN_S
 AC_PROG_MAKE_SET
-AC_PROG_LIBTOOL
+
+dnl libtool/libtoolize; version 2.4.2 is the tested version, this or any
+dnl compatible later version may be used
+LT_INIT([win32-dll])
+LT_PREREQ([2.4.2])
+
+# Some awks crash when confronted with pnglibconf.dfa, do a test run now
+# to make sure this doesn't happen
+AC_MSG_CHECKING([that AWK works])
+if ${AWK} -f ${srcdir}/scripts/options.awk out="/dev/null" version=search\
+   ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
+   ${srcdir}/pngusr.dfa 1>&2
+then
+   AC_MSG_RESULT([ok])
+else
+   AC_MSG_FAILURE([failed], 1)
+fi
+
+# This is a remnant of the old cc -E validation, where it may have been
+# necessary to use a different preprocessor for .dfn files
+DFNCPP="$CPP"
+AC_SUBST(DFNCPP)
+
+# -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
+# checks the compiler with a program that generates a warning), add the
+# following option to deal with this
+AC_ARG_VAR(PNG_COPTS,
+   [additional flags for the C compiler, use this for options that would]
+   [cause configure itself to fail])
+AC_ARG_ENABLE(werror,
+   AS_HELP_STRING([[[--enable-werror[=OPT]]]],
+      [Pass -Werror or the given argument to the compiler if it is supported]),
+   [test "$enable_werror" = "yes" && enable_werror="-Werror"
+    if test "$enable_werror" != "no"; then
+      sav_CFLAGS="$CFLAGS"
+      CFLAGS="$enable_werror $CFLAGS"
+      AC_MSG_CHECKING([if the compiler allows $enable_werror])
+      AC_COMPILE_IFELSE(
+         [AC_LANG_SOURCE([
+            [int main(int argc, char **argv){]
+            [return argv[argc-1][0];]
+            [}]])],
+         AC_MSG_RESULT(yes)
+         PNG_COPTS="$PNG_COPTS $enable_werror",
+         AC_MSG_RESULT(no))
+      CFLAGS="$sav_CFLAGS"
+    fi],)
 
 # Checks for header files.
 AC_HEADER_STDC
-AC_CHECK_HEADERS([malloc.h stdlib.h string.h strings.h])
+# Headers used in pngpriv.h:
+AC_CHECK_HEADERS([assert.h stdlib.h string.h float.h fp.h math.h m68881.h])
+# Additional headers used in pngconf.h:
+AC_CHECK_HEADERS([limits.h stddef.h stdio.h setjmp.h time.h])
+# Used by pngread.c (for the simplified API):
+AC_CHECK_HEADERS([errno.h])
+# The following are not required for the standard 'make' build of libpng:
+# Additional requirements of contrib/libtests/makepng.c:
+AC_CHECK_HEADERS([ctype.h])
+# Additional requirements of contrib/libtests/pngvalid.c:
+AC_CHECK_HEADERS([fenv.h])
 
 # Checks for typedefs, structures, and compiler characteristics.
-AC_C_CONST
-AC_TYPE_SIZE_T
-AC_STRUCT_TM
+# Most of these have been removed from 1.7.0 because they checked for non-ANSI-C
+# behaviors and the result were, anyway, not used by earlier versions of libpng.
+AC_C_RESTRICT
 
-# Checks for library functions.
-AC_FUNC_MALLOC
-AC_FUNC_STRTOD
-AC_CHECK_FUNCS([memset], , AC_ERROR([memset not found in libc]))
-AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_ERROR([cannot find pow])) )
-AC_CHECK_LIB(z, zlibVersion, , AC_ERROR([zlib not installed]))
+# Checks for library functions; these need to be in order, least demanding to
+# most because the -l directives are added to the head of the list at each
+# check.
+# ANSI-C functions: all are required but they don't have to be implemented in
+# libc, it is perfectly ok to configure with an extra, wrapper, library preset
+# in LIBS.  NOTE: this list may not be complete
+AC_CHECK_FUNCS([memset memcpy strncpy],,
+               AC_MSG_FAILURE([missing ANSI-C functions]))
 
-AC_MSG_CHECKING([if assembler code in pnggccrd.c can be compiled])
-AC_TRY_COMPILE(
-  [#include "pnggccrd.c"],
-  [return 0;],
-  LIBPNG_DEFINES=,
-  LIBPNG_DEFINES=-DPNG_CONFIGURE_LIBPNG -DPNG_NO_ASSEMBLER_CODE)
-if test "$LIBPNG_DEFINES"; then
-    AC_MSG_RESULT(no)
-else
-    AC_MSG_RESULT(yes)
-    LIBPNG_DEFINES=-DPNG_CONFIGURE_LIBPNG
+# floor and ceil are required for FLOATING_POINT, but they can be turned off on
+# the configure command line (and they are independent.)  Default is to 'on'
+AC_ARG_ENABLE([floating-point],[Enable floating point APIs],,
+              [enable_floating_point=yes])
+AC_ARG_ENABLE([fixed-point],[Enable fixed point APIs],,
+              [enable_fixed_point=yes])
+AC_ARG_ENABLE([floating-arithmetic],[Use floating point arithmetic internally],,
+              [enable_floating_arithmetic=yes])
+
+# Check for a requirement for math library support
+if test "$enable_floating_arithmetic" = yes
+then
+   AC_SEARCH_LIBS([floor],[m],,
+                  [AC_MSG_WARN([not found])
+                   enable_floating_arithmetic=no])
+   AC_SEARCH_LIBS([frexp],[m],,
+                  [AC_MSG_WARN([not found])
+                   enable_floating_arithmetic=no])
+   AC_SEARCH_LIBS([modf],[m],,
+                  [AC_MSG_WARN([not found])
+                   enable_floating_arithmetic=no])
+   AC_SEARCH_LIBS([atof],[m],,
+                  [AC_MSG_WARN([not found])
+                   enable_floating_arithmetic=no])
+   AC_SEARCH_LIBS([pow],[m],,
+                  [AC_MSG_WARN([not found])
+                   enable_floating_arithmetic=no])
 fi
-AC_SUBST(LIBPNG_DEFINES)
+
+# Set the relevant defines if required (only if required), this will override
+# anything on the command line.
+if test "$enable_floating_point" != yes
+then
+   AC_MSG_NOTICE([Floating point APIs disabled])
+   AC_DEFINE([PNG_NO_FLOATING_POINT],[1],
+             [No support for floating point APIs])
+fi
+if test "$enable_fixed_point" != yes
+then
+   AC_MSG_NOTICE([Fixed point APIs disabled])
+   AC_DEFINE([PNG_NO_FIXED_POINT],[1],
+             [No support for fixed point APIs])
+fi
+if test "$enable_floating_arithmetic" != yes
+then
+   AC_MSG_NOTICE([Fixed point arithmetic will be used])
+   AC_DEFINE([PNG_NO_FLOATING_ARITHMETIC],[1],
+             [No support for floating point arithmetic])
+fi
+
+# The following is for pngvalid, to ensure it catches FP errors even on
+# platforms that don't enable FP exceptions, the function appears in the math
+# library (typically), it's not an error if it is not found.
+AC_SEARCH_LIBS([feenableexcept],[m],AC_DEFINE([HAVE_FEENABLEEXCEPT],[1],
+      [Define to 1 if the feenableexcept function is available]))
+# Required by pngvalid:
+AC_SEARCH_LIBS([ceil],[m])
+
+# zlib checks and arguments;
+#  package zlib: argument is the name of the library
+#  zlib-header: the name of the header file
+#  zlib-prefix: the prefix for library functions, if any
+AC_ARG_WITH([zlib],
+   AS_HELP_STRING([[[--with-zlib=<name>]]],
+                  [base name of the zlib implementation (e.g. 'z')]),,
+   [with_zlib='z'])
+
+z_prefix=
+AC_ARG_WITH([zlib-prefix],
+   AS_HELP_STRING([[[--with-zlib-prefix=<prefix>]]],
+                  [prefix for zlib API functions]),
+   [if test "$withval" = "" -o "$withval" = yes; then
+      with_zlib_prefix='z_'
+      AC_DEFINE([PNG_ZLIB_PREFIX],[z_],[Standard zlib prefix])
+   elif test "${withval}" != "no"; then
+      AC_DEFINE_UNQUOTED([PNG_ZLIB_PREFIX],[${withval}],
+         [User defined zlib prefix])
+   else
+      with_zlib_prefix=
+   fi
+   if test "$with_zlib_prefix" != ""; then
+      AC_DEFINE([Z_PREFIX],[1],[Tell zlib.h to prefix function names])
+      z_prefix="#define Z_PREFIX 1"
+   fi])
+
+AC_ARG_WITH([zlib-header],
+   AS_HELP_STRING([[[--with-zlib-header='<file>' or '"file"']]],
+      [C include argument to locate zlib header file, e.g. <zlib.h>, take
+       care to put single quotes round this on the command line]),
+   [AC_DEFINE_UNQUOTED([PNG_ZLIB_HEADER],[${withval}],[Zlib header file])],
+   with_zlib_header='<zlib.h>')
+
+# AC_CHECK_LIB isn't quite enough for this because we need the special header
+# file too.
+LIBS="-l${with_zlib} $LIBS"
+AC_MSG_CHECKING(
+   [[Library '${with_zlib}' and #include ${with_zlib_header} for symbol '${with_zlib_prefix}zlibVersion']])
+AC_LINK_IFELSE(
+   [AC_LANG_PROGRAM(
+      [[
+${z_prefix}
+#include ${with_zlib_header}
+      ]],
+      [[(void)${with_zlib_prefix}zlibVersion();]])],
+   AC_MSG_RESULT([ok]),
+   AC_MSG_FAILURE([not found]))
+
+AC_MSG_CHECKING([if using Solaris linker])
+SLD=`$LD --version 2>&1 | grep Solaris`
+if test "$SLD"; then
+    have_solaris_ld=yes
+    AC_MSG_RESULT(yes)
+else
+    have_solaris_ld=no
+    AC_MSG_RESULT(no)
+fi
+AM_CONDITIONAL(HAVE_SOLARIS_LD, test "$have_solaris_ld" = "yes")
 
 AC_MSG_CHECKING([if libraries can be versioned])
-GLD=`$LD --help < /dev/null 2>/dev/null | grep version-script`
+# Special case for PE/COFF platforms: ld reports
+# support for version-script, but doesn't actually
+# DO anything with it.
+case $host in
+*cygwin* | *mingw32* | *interix* )
+    have_ld_version_script=no
+    AC_MSG_RESULT(no)
+;;
+* )
+
+if test "$have_solaris_ld" = "yes"; then
+    GLD=`$LD --help < /dev/null 2>&1 | grep 'M mapfile'`
+else
+    GLD=`$LD --help < /dev/null 2>/dev/null | grep version-script`
+fi
+
 if test "$GLD"; then
     have_ld_version_script=yes
     AC_MSG_RESULT(yes)
 else
     have_ld_version_script=no
     AC_MSG_RESULT(no)
-    AC_MSG_WARN(*** You may want to rerun configure using --with-gnu-ld to enable versioned symbols.)
+    AC_MSG_WARN(*** You have not enabled versioned symbols.)
 fi
+;;
+esac
+
 AM_CONDITIONAL(HAVE_LD_VERSION_SCRIPT, test "$have_ld_version_script" = "yes")
 
+if test "$have_ld_version_script" = "yes"; then
+    AC_MSG_CHECKING([for symbol prefix])
+    SYMBOL_PREFIX=`echo "PREFIX=__USER_LABEL_PREFIX__" \
+                  | ${CPP-${CC-gcc} -E} - 2>&1 \
+                  | ${EGREP-grep} "^PREFIX=" \
+                  | ${SED-sed} -e "s:^PREFIX=::" -e "s:__USER_LABEL_PREFIX__::"`
+    AC_SUBST(SYMBOL_PREFIX)
+    AC_MSG_RESULT($SYMBOL_PREFIX)
+fi
+
 # Substitutions for .in files
 AC_SUBST(PNGLIB_VERSION)
 AC_SUBST(PNGLIB_MAJOR)
 AC_SUBST(PNGLIB_MINOR)
+AC_SUBST(PNGLIB_RELEASE)
 
 # Additional arguments (and substitutions)
 # Allow the pkg-config directory to be set
 AC_ARG_WITH(pkgconfigdir,
-	AC_HELP_STRING([--with-pkgconfigdir],
+   AS_HELP_STRING([[[--with-pkgconfigdir]]],
       [Use the specified pkgconfig dir (default is libdir/pkgconfig)]),
    [pkgconfigdir=${withval}],
    [pkgconfigdir='${libdir}/pkgconfig'])
 
 AC_SUBST([pkgconfigdir])
-AC_MSG_NOTICE([pkgconfig directory is ${pkgconfigdir}])
+AC_MSG_NOTICE([[pkgconfig directory is ${pkgconfigdir}]])
 
 # Make the *-config binary config scripts optional
 AC_ARG_WITH(binconfigs,
-	AC_HELP_STRING([--with-binconfigs],
+   AS_HELP_STRING([[[--with-binconfigs]]],
       [Generate shell libpng-config scripts as well as pkg-config data]
       [@<:@default=yes@:>@]),
    [if test "${withval}" = no; then
       binconfigs=
-		AC_MSG_NOTICE([libpng-config scripts will not be built])
+      AC_MSG_NOTICE([[libpng-config scripts will not be built]])
     else
       binconfigs='${binconfigs}'
     fi],
    [binconfigs='${binconfigs}'])
 AC_SUBST([binconfigs])
 
-# Allow the old version number library, libpng.so, to be removed from
-# the build
-AC_ARG_WITH(libpng-compat,
-	AC_HELP_STRING([--with-libpng-compat],
-		[Generate the obsolete libpng.so library @<:@default=yes@:>@]),
-	[if test "${withval}" = no; then
-		compatlib=
-		AC_MSG_NOTICE([libpng.so will not be built])
-	else
-		compatlib=libpng.la
-	fi],
-	[compatlib=libpng.la])
-AC_SUBST([compatlib])
+# Support for prefixes to the API function names; this will generate defines
+# at the start of the build to rename exported library functions
+AC_ARG_WITH(libpng-prefix,
+   AS_HELP_STRING([[[--with-libpng-prefix]]],
+      [prefix libpng exported function (API) names with the given value]),
+   [if test "${withval:-no}" != "no"; then
+      AC_SUBST([PNG_PREFIX], [${withval}])
+    fi])
+AM_CONDITIONAL([DO_PNG_PREFIX], [test "${with_libpng_prefix:-no}" != "no"])
+
+# Because GCC by default assembles code with an executable stack, even though it
+# compiles C code with a non-executable stack, it is necessary to do a fixup
+# here (this may by GCC specific)
+AC_SUBST([AM_CCASFLAGS], [-Wa,--noexecstack])
+
+AC_ARG_ENABLE([arm-neon],
+   AS_HELP_STRING([[[--enable-arm-neon]]], [Enable ARM NEON optimizations]),
+   [if test "${enableval}" = "yes"; then
+      AC_DEFINE([PNG_FILTER_OPTIMIZATIONS],
+                [png_init_filter_functions_neon],
+                [ARM NEON filter initialization function])
+      AC_DEFINE([PNG_ALIGNED_MEMORY_SUPPORTED], [1],
+                [Align row buffers])
+    fi])
+AM_CONDITIONAL([PNG_ARM_NEON], [test "${enable_arm_neon:-no}" = yes])
+
+AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
 
 # Config files, substituting as above
-AC_CONFIG_FILES([Makefile libpng.pc:scripts/libpng.pc.in])
-AC_CONFIG_FILES([libpng-config:scripts/libpng-config.in],
-		[chmod +x libpng-config])
+AC_CONFIG_FILES([Makefile libpng.pc])
+AC_CONFIG_FILES([libpng-config], [chmod +x libpng-config])
 
 AC_OUTPUT

contrib/README.txt

@@ -0,0 +1,4 @@
+
+This "contrib" directory contains contributions which are not necessarily under
+the libpng license, although all are open source.  They are not part of
+libpng proper and are not used for building the library.

contrib/examples/README.txt

@@ -0,0 +1,24 @@
+
+This directory (contrib/examples) contains examples of libpng usage.
+
+NO COPYRIGHT RIGHTS ARE CLAIMED TO ANY OF THE FILES IN THIS DIRECTORY.
+
+To the extent possible under law, the authors have waived all copyright and
+related or neighboring rights to this work.  This work is published from:
+United States.
+
+The files may be used freely in any way.  The intention is that appropriate
+parts of the files be used in other libpng-using programs without any need for
+the authors of the using code to seek copyright or license from the original
+authors.
+
+The source code and comments in this directory are the original work of the
+people named below.  No other person or organization has made contributions to
+the work in this directory.
+
+ORIGINAL AUTHORS
+    The following people have contributed to the code in this directory.  None
+    of the people below claim any rights with regard to the contents of this
+    directory.
+
+    John Bowler <jbowler@acm.org>

contrib/examples/iccfrompng.c

@@ -0,0 +1,180 @@
+/*- iccfrompng
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2011.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work.  This work is published from:
+ * United States.
+ *
+ * Extract any icc profiles found in the given PNG files.  This is a simple
+ * example of a program which extracts information from the header of a PNG file
+ * without processing the image.  Notice that some header information may occur
+ * after the image data, textual data and comments are an example; the approach
+ * in this file won't work reliably for such data because it only looks for the
+ * information in the section of the file that preceeds the image data.
+ *
+ * Compile and link against libpng and zlib, plus anything else required on the
+ * system you use.
+ *
+ * To use supply a list of PNG files containing iCCP chunks, the chunks will be
+ * extracted to a similarly named file with the extension replaced by 'icc',
+ * which will be overwritten without warning.
+ */
+#include <stdlib.h>
+#include <setjmp.h>
+#include <string.h>
+#include <stdio.h>
+
+#include <png.h>
+
+static int verbose = 1;
+static png_byte no_profile[] = "no profile";
+
+static png_bytep
+extract(FILE *fp, png_uint_32 *proflen)
+{
+   png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);
+   png_infop info_ptr = NULL;
+   png_bytep result = NULL;
+
+   /* Initialize for error or no profile: */
+   *proflen = 0;
+
+   if (png_ptr == NULL)
+   {
+      fprintf(stderr, "iccfrompng: version library mismatch?\n");
+      return 0;
+   }
+
+   if (setjmp(png_jmpbuf(png_ptr)))
+   {
+      png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+      return 0;
+   }
+
+   png_init_io(png_ptr, fp);
+
+   info_ptr = png_create_info_struct(png_ptr);
+   if (info_ptr == NULL)
+      png_error(png_ptr, "OOM allocating info structure");
+
+   png_read_info(png_ptr, info_ptr);
+
+   {
+      png_charp name;
+      int compression_type;
+      png_bytep profile;
+
+      if (png_get_iCCP(png_ptr, info_ptr, &name, &compression_type, &profile,
+         proflen) & PNG_INFO_iCCP)
+      {
+         result = malloc(*proflen);
+         if (result != NULL)
+            memcpy(result, profile, *proflen);
+
+         else
+            png_error(png_ptr, "OOM allocating profile buffer");
+      }
+
+      else
+	result = no_profile;
+   }
+
+   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+   return result;
+}
+
+static int
+extract_one_file(const char *filename)
+{
+   int result = 0;
+   FILE *fp = fopen(filename, "rb");
+
+   if (fp != NULL)
+   {
+      png_uint_32 proflen = 0;
+      png_bytep profile = extract(fp, &proflen);
+
+      if (profile != NULL && profile != no_profile)
+      {
+         size_t len;
+         char *output;
+
+         {
+            const char *ep = strrchr(filename, '.');
+
+            if (ep != NULL)
+               len = ep-filename;
+
+            else
+               len = strlen(filename);
+         }
+
+         output = malloc(len + 5);
+         if (output != NULL)
+         {
+            FILE *of;
+
+            memcpy(output, filename, len);
+            strcpy(output+len, ".icc");
+
+            of = fopen(output, "wb");
+            if (of != NULL)
+            {
+               if (fwrite(profile, proflen, 1, of) == 1 &&
+                  fflush(of) == 0 &&
+                  fclose(of) == 0)
+               {
+                  if (verbose)
+                     printf("%s -> %s\n", filename, output);
+                  /* Success return */
+                  result = 1;
+               }
+
+               else
+               {
+                  fprintf(stderr, "%s: error writing profile\n", output);
+                  if (remove(output))
+                     fprintf(stderr, "%s: could not remove file\n", output);
+               }
+            }
+
+            else
+               fprintf(stderr, "%s: failed to open output file\n", output);
+
+            free(output);
+         }
+
+         else
+            fprintf(stderr, "%s: OOM allocating string!\n", filename);
+
+         free(profile);
+      }
+
+      else if (verbose && profile == no_profile)
+	printf("%s has no profile\n", filename);
+   }
+
+   else
+      fprintf(stderr, "%s: could not open file\n", filename);
+
+   return result;
+}
+
+int
+main(int argc, char **argv)
+{
+   int i;
+   int extracted = 0;
+
+   for (i=1; i<argc; ++i)
+   {
+      if (strcmp(argv[i], "-q") == 0)
+         verbose = 0;
+
+      else if (extract_one_file(argv[i]))
+         extracted = 1;
+   }
+
+   /* Exit code is true if any extract succeeds */
+   return extracted == 0;
+}

contrib/examples/pngpixel.c

@@ -0,0 +1,368 @@
+/*- pngpixel
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2011.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work.  This work is published from:
+ * United States.
+ *
+ * Read a single pixel value from a PNG file.
+ *
+ * This code illustrates basic 'by-row' reading of a PNG file using libpng.
+ * Rows are read until a particular pixel is found, the value of this pixel is
+ * then printed on stdout.
+ *
+ * The code illustrates how to do this on interlaced as well as non-interlaced
+ * images.  Normally you would call png_set_interlace_handling() to have libpng
+ * deal with the interlace for you, but that obliges you to buffer half of the
+ * image to assemble the interlaced rows.  In this code
+ * png_set_interlace_handling() is not called and, instead, the code handles the
+ * interlace passes directly looking for the required pixel.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <setjmp.h> /* required for error handling */
+
+/* Normally use <png.h> here to get the installed libpng, but this is done to
+ * ensure the code picks up the local libpng implementation:
+ */
+#include "../../png.h"
+
+/* Return component 'c' of pixel 'x' from the given row. */
+static unsigned int
+component(png_const_bytep row, png_uint_32 x, unsigned int c,
+   unsigned int bit_depth, unsigned int channels)
+{
+   /* PNG images can be up to 2^31 pixels wide, but this means they can be up to
+    * 2^37 bits wide (for a 64-bit pixel - the largest possible) and hence 2^34
+    * bytes wide.  Since the row fitted into memory, however, the following must
+    * work:
+    */
+   png_uint_32 bit_offset_hi = bit_depth * ((x >> 6) * channels + c);
+   png_uint_32 bit_offset_lo = bit_depth * ((x & 0x3f) * channels + c);
+
+   row = (png_const_bytep)(((PNG_CONST png_byte (*)[8])row) + bit_offset_hi);
+   row += bit_offset_lo >> 3;
+   bit_offset_lo &= 0x07;
+
+   /* PNG pixels are packed into bytes to put the first pixel in the highest
+    * bits of the byte and into two bytes for 16-bit values with the high 8 bits
+    * first, so:
+    */
+   switch (bit_depth)
+   {
+      case 1: return (row[0] >> (7-bit_offset_lo)) & 0x01;
+      case 2: return (row[0] >> (6-bit_offset_lo)) & 0x03;
+      case 4: return (row[0] >> (4-bit_offset_lo)) & 0x0f;
+      case 8: return row[0];
+      case 16: return (row[0] << 8) + row[1];
+      default:
+         /* This should never happen, it indicates a bug in this program or in
+          * libpng itself:
+          */
+         fprintf(stderr, "pngpixel: invalid bit depth %u\n", bit_depth);
+         exit(1);
+   }
+}
+
+/* Print a pixel from a row returned by libpng; determine the row format, find
+ * the pixel, and print the relevant information to stdout.
+ */
+static void
+print_pixel(png_structp png_ptr, png_infop info_ptr, png_const_bytep row,
+   png_uint_32 x)
+{
+   PNG_CONST unsigned int bit_depth = png_get_bit_depth(png_ptr, info_ptr);
+
+   switch (png_get_color_type(png_ptr, info_ptr))
+   {
+      case PNG_COLOR_TYPE_GRAY:
+         printf("GRAY %u\n", component(row, x, 0, bit_depth, 1));
+         return;
+
+      /* The palette case is slightly more difficult - the palette and, if
+       * present, the tRNS ('transparency', though the values are really
+       * opacity) data must be read to give the full picture:
+       */
+      case PNG_COLOR_TYPE_PALETTE:
+         {
+            PNG_CONST unsigned int index = component(row, x, 0, bit_depth, 1);
+            png_colorp palette = NULL;
+            int num_palette = 0;
+
+            if ((png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette) &
+               PNG_INFO_PLTE) && num_palette > 0 && palette != NULL)
+            {
+               png_bytep trans_alpha = NULL;
+               int num_trans = 0;
+               if ((png_get_tRNS(png_ptr, info_ptr, &trans_alpha, &num_trans,
+                  NULL) & PNG_INFO_tRNS) && num_trans > 0 &&
+                  trans_alpha != NULL)
+                  printf("INDEXED %u = %d %d %d %d\n", index,
+                     palette[index].red, palette[index].green,
+                     palette[index].blue,
+                     index < num_trans ? trans_alpha[index] : 255);
+
+               else /* no transparency */
+                  printf("INDEXED %u = %d %d %d\n", index,
+                     palette[index].red, palette[index].green,
+                     palette[index].blue);
+            }
+
+            else
+               printf("INDEXED %u = invalid index\n", index);
+         }
+         return;
+
+      case PNG_COLOR_TYPE_RGB:
+         printf("RGB %u %u %u\n", component(row, x, 0, bit_depth, 3),
+            component(row, x, 1, bit_depth, 3),
+            component(row, x, 2, bit_depth, 3));
+         return;
+
+      case PNG_COLOR_TYPE_GRAY_ALPHA:
+         printf("GRAY+ALPHA %u %u\n", component(row, x, 0, bit_depth, 2),
+            component(row, x, 1, bit_depth, 2));
+         return;
+
+      case PNG_COLOR_TYPE_RGB_ALPHA:
+         printf("RGBA %u %u %u %u\n", component(row, x, 0, bit_depth, 4),
+            component(row, x, 1, bit_depth, 4),
+            component(row, x, 2, bit_depth, 4),
+            component(row, x, 3, bit_depth, 4));
+         return;
+
+      default:
+         png_error(png_ptr, "invalid color type");
+   }
+}
+
+int main(int argc, const char **argv)
+{
+   /* This program uses the default, <setjmp.h> based, libpng error handling
+    * mechanism, therefore any local variable that exists before the call to
+    * setjmp and is changed after the call to setjmp returns successfully must
+    * be declared with 'volatile' to ensure that their values don't get
+    * destroyed by longjmp:
+    */
+   volatile int result = 1/*fail*/;
+
+   if (argc == 4)
+   {
+      long x = atol(argv[1]);
+      long y = atol(argv[2]);
+      FILE *f = fopen(argv[3], "rb");
+      volatile png_bytep row = NULL;
+
+      if (f != NULL)
+      {
+         /* libpng requires a callback function for handling errors; this
+          * callback must not return.  The default callback function uses a
+          * stored <setjmp.h> style jmp_buf which is held in a png_struct and
+          * writes error messages to stderr.  Creating the png_struct is a
+          * little tricky; just copy the following code.
+          */
+         png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
+            NULL, NULL, NULL);
+
+         if (png_ptr != NULL)
+         {
+            png_infop info_ptr = png_create_info_struct(png_ptr);
+
+            if (info_ptr != NULL)
+            {
+               /* Declare stack variables to hold pointers to locally allocated
+                * data.
+                */
+
+               /* Initialize the error control buffer: */
+               if (setjmp(png_jmpbuf(png_ptr)) == 0)
+               {
+                  png_uint_32 width, height;
+                  int bit_depth, color_type, interlace_method,
+                     compression_method, filter_method;
+                  png_bytep row_tmp;
+
+                  /* Now associate the recently opened (FILE*) with the default
+                   * libpng initialization functions.  Sometimes libpng is
+                   * compiled without stdio support (it can be difficult to do
+                   * in some environments); in that case you will have to write
+                   * your own read callback to read data from the (FILE*).
+                   */
+                  png_init_io(png_ptr, f);
+
+                  /* And read the first part of the PNG file - the header and
+                   * all the information up to the first pixel.
+                   */
+                  png_read_info(png_ptr, info_ptr);
+
+                  /* This fills in enough information to tell us the width of
+                   * each row in bytes, allocate the appropriate amount of
+                   * space.  In this case png_malloc is used - it will not
+                   * return if memory isn't available.
+                   */
+                  row = png_malloc(png_ptr, png_get_rowbytes(png_ptr,
+                     info_ptr));
+
+                  /* To avoid the overhead of using a volatile auto copy row_tmp
+                   * to a local here - just use row for the png_free below.
+                   */
+                  row_tmp = row;
+
+                  /* All the information we need is in the header is returned by
+                   * png_get_IHDR, if this fails we can now use 'png_error' to
+                   * signal the error and return control to the setjmp above.
+                   */
+                  if (png_get_IHDR(png_ptr, info_ptr, &width, &height,
+                     &bit_depth, &color_type, &interlace_method,
+                     &compression_method, &filter_method))
+                  {
+                     int passes, pass;
+
+                     /* png_set_interlace_handling returns the number of
+                      * passes required as well as turning on libpng's
+                      * handling, but since we do it ourselves this is
+                      * necessary:
+                      */
+                     switch (interlace_method)
+                     {
+                        case PNG_INTERLACE_NONE:
+                           passes = 1;
+                           break;
+
+                        case PNG_INTERLACE_ADAM7:
+                           passes = PNG_INTERLACE_ADAM7_PASSES;
+                           break;
+
+                        default:
+                           png_error(png_ptr, "pngpixel: unknown interlace");
+                     }
+
+                     /* Now read the pixels, pass-by-pass, row-by-row: */
+                     png_start_read_image(png_ptr);
+
+                     for (pass=0; pass<passes; ++pass)
+                     {
+                        png_uint_32 ystart, xstart, ystep, xstep;
+                        png_uint_32 py;
+
+                        if (interlace_method == PNG_INTERLACE_ADAM7)
+                        {
+                           /* Sometimes the whole pass is empty because the
+                            * image is too narrow or too short.  libpng
+                            * expects to be called for each row that is
+                            * present in the pass, so it may be necessary to
+                            * skip the loop below (over py) if the image is
+                            * too narrow.
+                            */
+                           if (PNG_PASS_COLS(width, pass) == 0)
+                              continue;
+
+                           /* We need the starting pixel and the offset
+                            * between each pixel in this pass; use the macros
+                            * in png.h:
+                            */
+                           xstart = PNG_PASS_START_COL(pass);
+                           ystart = PNG_PASS_START_ROW(pass);
+                           xstep = PNG_PASS_COL_OFFSET(pass);
+                           ystep = PNG_PASS_ROW_OFFSET(pass);
+                        }
+
+                        else
+                        {
+                           ystart = xstart = 0;
+                           ystep = xstep = 1;
+                        }
+
+                        /* To find the pixel, loop over 'py' for each pass
+                         * reading a row and then checking to see if it
+                         * contains the pixel.
+                         */
+                        for (py = ystart; py < height; py += ystep)
+                        {
+                           png_uint_32 px, ppx;
+
+                           /* png_read_row takes two pointers.  When libpng
+                            * handles the interlace the first is filled in
+                            * pixel-by-pixel, and the second receives the same
+                            * pixels but they are replicated across the
+                            * unwritten pixels so far for each pass.  When we
+                            * do the interlace, however, they just contain
+                            * the pixels from the interlace pass - giving
+                            * both is wasteful and pointless, so we pass a
+                            * NULL pointer.
+                            */
+                           png_read_row(png_ptr, row_tmp, NULL);
+
+                           /* Now find the pixel if it is in this row; there
+                            * are, of course, much better ways of doing this
+                            * than using a for loop:
+                            */
+                           if (y == py) for (px = xstart, ppx = 0;
+                              px < width; px += xstep, ++ppx) if (x == px)
+                           {
+                              /* 'ppx' is the index of the pixel in the row
+                               * buffer.
+                               */
+                              print_pixel(png_ptr, info_ptr, row_tmp, ppx);
+
+                              /* Now terminate the loops early - we have
+                               * found and handled the required data.
+                               */
+                              goto pass_loop_end;
+                           } /* x loop */
+                        } /* y loop */
+                     } /* pass loop */
+
+                     /* Finally free the temporary buffer: */
+                  pass_loop_end:
+                     row = NULL;
+                     png_free(png_ptr, row_tmp);
+                  }
+
+                  else
+                     png_error(png_ptr, "pngpixel: png_get_IHDR failed");
+
+               }
+
+               else
+               {
+                  /* Else libpng has raised an error.  An error message has
+                   * already been output, so it is only necessary to clean up
+                   * locally allocated data:
+                   */
+                  if (row != NULL)
+                  {
+                     /* The default implementation of png_free never errors out
+                      * (it just crashes if something goes wrong), but the safe
+                      * way of using it is still to clear 'row' before calling
+                      * png_free:
+                      */
+                     png_bytep row_tmp = row;
+                     row = NULL;
+                     png_free(png_ptr, row_tmp);
+                  }
+               }
+
+               png_destroy_info_struct(png_ptr, &info_ptr);
+            }
+
+            else
+               fprintf(stderr, "pngpixel: out of memory allocating png_info\n");
+
+            png_destroy_read_struct(&png_ptr, NULL, NULL);
+         }
+
+         else
+            fprintf(stderr, "pngpixel: out of memory allocating png_struct\n");
+      }
+
+      else
+         fprintf(stderr, "pngpixel: %s: could not open file\n", argv[3]);
+   }
+
+   else
+      /* Wrong number of arguments */
+      fprintf(stderr, "pngpixel: usage: pngpixel x y png-file\n");
+
+   return result;
+}

contrib/examples/pngtopng.c

@@ -0,0 +1,92 @@
+/*- pngtopng
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2011.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work.  This work is published from:
+ * United States.
+ *
+ * Read a PNG and write it out in a fixed format, using the 'simplified API'
+ * that was introduced in libpng-1.6.0.
+ *
+ * This sample code is just the code from the top of 'example.c' with some error
+ * handling added.  See example.c for more comments.
+ */
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+/* Normally use <png.h> here to get the installed libpng, but this is done to
+ * ensure the code picks up the local libpng implementation:
+ */
+#include "../../png.h"
+
+int main(int argc, const char **argv)
+{
+   int result = 1;
+
+   if (argc == 3)
+   {
+      png_image image;
+
+      /* Only the image structure version number needs to be set. */
+      memset(&image, 0, sizeof image);
+      image.version = PNG_IMAGE_VERSION;
+
+      if (png_image_begin_read_from_file(&image, argv[1]))
+      {
+         png_bytep buffer;
+
+         /* Change this to try different formats!  If you set a colormap format
+          * then you must also supply a colormap below.
+          */
+         image.format = PNG_FORMAT_RGBA;
+
+         buffer = malloc(PNG_IMAGE_SIZE(image));
+
+         if (buffer != NULL)
+         {
+            if (png_image_finish_read(&image, NULL/*background*/, buffer,
+               0/*row_stride*/, NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP */))
+            {
+               if (png_image_write_to_file(&image, argv[2],
+                  0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
+                  NULL/*colormap*/))
+                  result = 0;
+
+               else
+                  fprintf(stderr, "pngtopng: write %s: %s\n", argv[2],
+                      image.message);
+
+               free(buffer);
+            }
+
+            else
+            {
+               fprintf(stderr, "pngtopng: read %s: %s\n", argv[1],
+                   image.message);
+
+               /* This is the only place where a 'free' is required; libpng does
+                * the cleanup on error and success, but in this case we couldn't
+                * complete the read because of running out of memory.
+                */
+               png_image_free(&image);
+            }
+         }
+
+         else
+            fprintf(stderr, "pngtopng: out of memory: %lu bytes\n",
+               (unsigned long)PNG_IMAGE_SIZE(image));
+      }
+
+      else
+         /* Failed to read the first argument: */
+         fprintf(stderr, "pngtopng: %s: %s\n", argv[1], image.message);
+   }
+
+   else
+      /* Wrong number of arguments */
+      fprintf(stderr, "pngtopng: usage: pngtopng input-file output-file\n");
+
+   return result;
+}

contrib/gregbook/COPYING

@@ -0,0 +1,340 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
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+    License.  (Exception: if the Program itself is interactive but
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+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
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+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
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+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
+    machine-readable copy of the corresponding source code, to be
+    distributed under the terms of Sections 1 and 2 above on a medium
+    customarily used for software interchange; or,
+
+    c) Accompany it with the information you received as to the offer
+    to distribute corresponding source code.  (This alternative is
+    allowed only for noncommercial distribution and only if you
+    received the program in object code or executable form with such
+    an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+  5. You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
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+through that system in reliance on consistent application of that
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+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
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+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+                            NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year  name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.

contrib/gregbook/LICENSE

@@ -1,12 +1,19 @@
   ---------------------------------------------------------------------------
 
-      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -23,4 +30,21 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------

contrib/gregbook/Makefile.mingw32

@@ -0,0 +1,130 @@
+# Sample makefile for rpng-win / rpng2-win / wpng using mingw32-gcc and make.
+# Greg Roelofs
+# Last modified:  2 June 2007
+#
+#	The programs built by this makefile are described in the book,
+#	"PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
+#	Associates, 1999).  Go buy a copy, eh?  Well, OK, it's not
+#	generally for sale anymore, but it's the thought that counts,
+#	right?  (Hint:  http://www.libpng.org/pub/png/book/ )
+#
+# Invoke this makefile from a DOS-prompt window via:
+#
+#	make -f Makefile.mingw32
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are in subdirectories at the same level as the current subdirectory
+# (as indicated by the PNGDIR and ZDIR macros below).  It makes no assumptions
+# at all about the mingw32 installation tree (W32DIR).  Edit as appropriate.
+#
+# Note that the names of the dynamic and static libpng and zlib libraries
+# used below may change in later releases of the libraries.  This makefile
+# builds both statically and dynamically linked executables by default.
+# (You need only one set, but for testing it can be handy to have both.)
+
+
+# macros --------------------------------------------------------------------
+
+#PNGDIR = ../..#		for libpng-x.y.z/contrib/gregbook builds
+PNGDIR = ../libpng-win32
+PNGINC = -I$(PNGDIR)
+PNGLIBd = $(PNGDIR)/libpng.dll.a	# dynamically linked
+PNGLIBs = $(PNGDIR)/libpng.a		# statically linked, local libpng
+
+#ZDIR = ../../../zlib-win32#	for libpng-x.y.z/contrib/gregbook builds
+ZDIR = ../zlib-win32
+ZINC = -I$(ZDIR)
+ZLIBd = $(ZDIR)/libzdll.a
+ZLIBs = $(ZDIR)/libz.a
+
+# change this to be the path where mingw32 installs its stuff:
+W32DIR =
+#W32DIR = /usr/local/cross-tools/i386-mingw32msvc
+W32INC = -I$(W32DIR)/include
+W32LIB = $(W32DIR)/lib/libuser32.a $(W32DIR)/lib/libgdi32.a
+
+CC = gcc
+#CC = i386-mingw32msvc-gcc #	e.g., Linux -> Win32 cross-compilation
+LD = $(CC)
+RM = rm -f
+CFLAGS = -O -Wall $(INCS) $(MINGW_CCFLAGS)
+# [note that -Wall is a gcc-specific compilation flag ("most warnings on")]
+# [-ansi, -pedantic and -W can also be used]
+LDFLAGS = $(MINGW_LDFLAGS)
+O = .o
+E = .exe
+
+INCS = $(PNGINC) $(ZINC) $(W32INC)
+RLIBSd = $(PNGLIBd) $(ZLIBd) $(W32LIB) -lm
+RLIBSs = $(PNGLIBs) $(ZLIBs) $(W32LIB) -lm
+WLIBSd = $(PNGLIBd) $(ZLIBd)
+WLIBSs = $(PNGLIBs) $(ZLIBs)
+
+RPNG   = rpng-win
+RPNG2  = rpng2-win
+WPNG   = wpng
+
+ROBJSd  = $(RPNG)$(O) readpng.pic$(O)
+ROBJS2d = $(RPNG2)$(O) readpng2.pic$(O)
+WOBJSd  = $(WPNG)$(O) writepng.pic$(O)
+
+RPNGs  = $(RPNG)-static
+RPNG2s = $(RPNG2)-static
+WPNGs  = $(WPNG)-static
+
+ROBJSs  = $(RPNG)$(O) readpng$(O)
+ROBJS2s = $(RPNG2)$(O) readpng2$(O)
+WOBJSs  = $(WPNG)$(O) writepng$(O)
+
+STATIC_EXES  = $(RPNGs)$(E) $(RPNG2s)$(E) $(WPNGs)$(E)
+DYNAMIC_EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+EXES = $(STATIC_EXES) $(DYNAMIC_EXES)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+	$(CC) -c $(CFLAGS) $<
+
+%.pic$(O): %.c
+	$(CC) -c $(CFLAGS) -DPNG_BUILD_DLL -o $@ $<
+
+
+# dependencies --------------------------------------------------------------
+
+all:  $(EXES)
+
+$(RPNGs)$(E): $(ROBJSs)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJSs) $(RLIBSs)
+
+$(RPNG)$(E): $(ROBJSd)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJSd) $(RLIBSd)
+
+$(RPNG2s)$(E): $(ROBJS2s)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS2s) $(RLIBSs)
+
+$(RPNG2)$(E): $(ROBJS2d)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS2d) $(RLIBSd)
+
+$(WPNGs)$(E): $(WOBJSs)
+	$(LD) $(LDFLAGS) -o $@ $(WOBJSs) $(WLIBSs)
+
+$(WPNG)$(E): $(WOBJSd)
+	$(LD) $(LDFLAGS) -o $@ $(WOBJSd) $(WLIBSd)
+
+$(RPNG)$(O):	$(RPNG).c readpng.h
+$(RPNG2)$(O):	$(RPNG2).c readpng2.h
+$(WPNG)$(O):	$(WPNG).c writepng.h
+
+readpng$(O) readpng.pic$(O):	readpng.c readpng.h
+readpng2$(O) readpng2.pic$(O):	readpng2.c readpng2.h
+writepng$(O) writepng.pic$(O):	writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+	$(RM) $(EXES)
+	$(RM) $(ROBJSs) $(ROBJS2s) $(WOBJSs)
+	$(RM) $(ROBJSd) $(ROBJS2d) $(WOBJSd)

contrib/gregbook/Makefile.sgi

@@ -23,9 +23,9 @@
 
 # macros --------------------------------------------------------------------
 
-PNGINC = -I/usr/local/include/libpng12
-PNGLIB = -L/usr/local/lib -lpng12	  # dynamically linked against libpng
-#PNGLIB = /usr/local/lib/libpng12.a # statically linked against libpng
+PNGINC = -I/usr/local/include/libpng17
+PNGLIB = -L/usr/local/lib -lpng17	  # dynamically linked against libpng
+#PNGLIB = /usr/local/lib/libpng17.a # statically linked against libpng
 # or:
 #PNGINC = -I../..
 #PNGLIB = -L../.. -lpng

contrib/gregbook/Makefile.unx

@@ -1,58 +1,70 @@
 # Sample makefile for rpng-x / rpng2-x / wpng using gcc and make.
 # Greg Roelofs
-# Last modified:  7 March 2002
+# Last modified:  2 June 2007
 #
 #	The programs built by this makefile are described in the book,
 #	"PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
-#	Associates, 1999).  Go buy a copy, eh?  Buy some for friends
-#	and family, too.  (Not that this is a blatant plug or anything.)
+#	Associates, 1999).  Go buy a copy, eh?  Well, OK, it's not
+#	generally for sale anymore, but it's the thought that counts,
+#	right?  (Hint:  http://www.libpng.org/pub/png/book/ )
 #
 # Invoke this makefile from a shell prompt in the usual way; for example:
 #
 #	make -f Makefile.unx
 #
 # This makefile assumes libpng and zlib have already been built or downloaded
-# and are both installed in /usr/local/{include,lib} (as indicated by the
-# PNG* and Z* macros below).  Edit as appropriate--choose only ONE each of
-# the PNGINC, PNGLIB, ZINC and ZLIB lines.
+# and are installed in /usr/local/{include,lib} or as otherwise indicated by
+# the PNG* and Z* macros below.  Edit as appropriate--choose only ONE each of
+# the PNGINC, PNGLIBd, PNGLIBs, ZINC, ZLIBd and ZLIBs lines.
 #
-# This makefile builds statically linked executables (against libpng and zlib,
-# that is), but that can be changed by uncommenting the appropriate PNGLIB and
-# ZLIB lines.
+# This makefile builds both dynamically and statically linked executables
+# (against libpng and zlib, that is), but that can be changed by modifying
+# the "EXES =" line.  (You need only one set, but for testing it can be handy
+# to have both.)
 
 
 # macros --------------------------------------------------------------------
 
-PNGINC = -I/usr/local/include/libpng12
-#PNGLIB = -L/usr/local/lib -lpng12 # dynamically linked against libpng
-PNGLIB = /usr/local/lib/libpng12.a # statically linked against libpng
+#PNGDIR = /usr/local/lib
+#PNGINC = -I/usr/local/include/libpng17
+#PNGLIBd = -L$(PNGDIR) -lpng17 # dynamically linked, installed libpng
+#PNGLIBs = $(PNGDIR)/libpng17.a # statically linked, installed libpng
 # or:
-#PNGINC = -I../libpng
-#PNGLIB = -L../libpng -lpng
-#PNGLIB = ../libpng/libpng.a
+PNGDIR = ../..#	this one is for libpng-x.y.z/contrib/gregbook builds
+#PNGDIR = ../libpng
+PNGINC = -I$(PNGDIR)
+PNGLIBd = -Wl,-rpath,$(PNGDIR) -L$(PNGDIR) -lpng17	# dynamically linked
+PNGLIBs = $(PNGDIR)/libpng.a		# statically linked, local libpng
 
+ZDIR = /usr/local/lib
+#ZDIR = /usr/lib64
 ZINC = -I/usr/local/include
-#ZLIB = -L/usr/local/lib -lz		# dynamically linked against zlib
-ZLIB = /usr/local/lib/libz.a		# statically linked against zlib
-#ZINC = -I../zlib
-#ZLIB = -L../zlib -lz
-#ZLIB = ../zlib/libz.a
+ZLIBd = -L$(ZDIR) -lz			# dynamically linked against zlib
+ZLIBs = $(ZDIR)/libz.a			# statically linked against zlib
+# or:
+#ZDIR = ../zlib
+#ZINC = -I$(ZDIR)
+#ZLIBd = -Wl,-rpath,$(ZDIR) -L$(ZDIR) -lz  # -rpath allows in-place testing
+#ZLIBs = $(ZDIR)/libz.a
 
 #XINC = -I/usr/include			# old-style, stock X distributions
-#XLIB = -L/usr/lib/X11 -lX11
+#XLIB = -L/usr/lib/X11 -lX11		#  (including SGI IRIX)
 #XINC = -I/usr/openwin/include		# Sun workstations (OpenWindows)
 #XLIB = -L/usr/openwin/lib -lX11
-XINC = -I/usr/X11R6/include		# new X distributions (XFree86, etc.)
+XINC = -I/usr/X11R6/include		# new X distributions (X.org, etc.)
 XLIB = -L/usr/X11R6/lib -lX11
+#XLIB = -L/usr/X11R6/lib64 -lX11	# e.g., Red Hat on AMD64
 
 INCS = $(PNGINC) $(ZINC) $(XINC)
-RLIBS = $(PNGLIB) $(ZLIB) $(XLIB) -lm
-WLIBS = $(PNGLIB) $(ZLIB)
+RLIBSd = $(PNGLIBd) $(ZLIBd) $(XLIB) -lm
+RLIBSs = $(PNGLIBs) $(ZLIBs) $(XLIB) -lm
+WLIBSd = $(PNGLIBd) $(ZLIBd) -lm
+WLIBSs = $(PNGLIBs) $(ZLIBs)
 
 CC = gcc
 LD = gcc
 RM = rm -f
-CFLAGS = -O -Wall $(INCS)
+CFLAGS = -O -Wall $(INCS) -DFEATURE_LOOP
 # [note that -Wall is a gcc-specific compilation flag ("most warnings on")]
 # [-ansi, -pedantic and -W can also be used]
 LDFLAGS =
@@ -63,11 +75,18 @@ RPNG  = rpng-x
 RPNG2  = rpng2-x
 WPNG   = wpng
 
+RPNGs  = $(RPNG)-static
+RPNG2s = $(RPNG2)-static
+WPNGs  = $(WPNG)-static
+
 ROBJS  = $(RPNG)$(O) readpng$(O)
 ROBJS2 = $(RPNG2)$(O) readpng2$(O)
 WOBJS  = $(WPNG)$(O) writepng$(O)
 
-EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+STATIC_EXES  = $(RPNGs)$(E) $(RPNG2s)$(E) $(WPNGs)$(E)
+DYNAMIC_EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+EXES = $(STATIC_EXES) $(DYNAMIC_EXES)
 
 
 # implicit make rules -------------------------------------------------------
@@ -80,14 +99,23 @@ EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
 
 all:  $(EXES)
 
+$(RPNGs)$(E): $(ROBJS)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBSs)
+
 $(RPNG)$(E): $(ROBJS)
-	$(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBS)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBSd)
+
+$(RPNG2s)$(E): $(ROBJS2)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBSs)
 
 $(RPNG2)$(E): $(ROBJS2)
-	$(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBS)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBSd)
+
+$(WPNGs)$(E): $(WOBJS)
+	$(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBSs)
 
 $(WPNG)$(E): $(WOBJS)
-	$(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBS)
+	$(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBSd)
 
 $(RPNG)$(O):	$(RPNG).c readpng.h
 $(RPNG2)$(O):	$(RPNG2).c readpng2.h

contrib/gregbook/Makefile.w32

@@ -1,11 +1,12 @@
 # Sample makefile for rpng-win / rpng2-win / wpng using MSVC and NMAKE.
 # Greg Roelofs
-# Last modified:  16 February 1999
+# Last modified:  2 June 2007
 #
 #	The programs built by this makefile are described in the book,
 #	"PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
-#	Associates, 1999).  Go buy a copy, eh?  Buy some for friends
-#	and family, too.  (Not that this is a blatant plug or anything.)
+#	Associates, 1999).  Go buy a copy, eh?  Well, OK, it's not
+#	generally for sale anymore, but it's the thought that counts,
+#	right?  (Hint:  http://www.libpng.org/pub/png/book/ )
 #
 # Invoke this makefile from a DOS prompt window via:
 #
@@ -53,7 +54,7 @@ CC = cl
 LD = link
 RM = del
 CFLAGS = -nologo -O -W3 $(INCS) $(cvars)
-# [note that -Wall is an MSVC-specific compilation flag ("all warnings on")]
+# [note that -W3 is an MSVC-specific compilation flag ("all warnings on")]
 # [see %devstudio%\vc\include\win32.mak for cvars macro definition]
 O = .obj
 E = .exe

contrib/gregbook/README

@@ -22,7 +22,8 @@ below.
 Files:
 
    README             this file
-   LICENSE            terms of distribution and reuse (BSD-like)
+   LICENSE            terms of distribution and reuse (BSD-like or GNU GPL)
+   COPYING            GNU General Public License (GPL)
 
    Makefile.unx       Unix makefile
    Makefile.w32       Windows (MSVC) makefile
@@ -54,15 +55,15 @@ mation and links to the latest version of the source code, and Chapters
 13-15 of the book for detailed discussion of the three programs.
 
 Greg Roelofs
-newt@pobox.com
-30 June 2001
+http://pobox.com/~newt/greg_contact.html
+16 March 2008
 
 
 BUILD INSTRUCTIONS
 
  - Prerequisites (in order of compilation):
 
-      - zlib		http://www.gzip.org/zlib/
+      - zlib            http://zlib.net/
       - libpng          http://www.libpng.org/pub/png/libpng.html
       - pngbook         http://www.libpng.org/pub/png/book/sources.html
 
@@ -164,7 +165,7 @@ RUNNING THE PROGRAMS:  (VERY) BRIEF INTRO
      rpng is a simple PNG viewer that can display transparent PNGs with a
      specified background color; for example,
 
-	rpng -bgcolor #ff0000 toucan.png
+        rpng -bgcolor \#ff0000 toucan.png
 
      would display the image with a red background.  rpng2 is a progressive
      viewer that simulates a web browser in some respects; it can display
@@ -176,7 +177,7 @@ RUNNING THE PROGRAMS:  (VERY) BRIEF INTRO
      wpng is a purely command-line image converter from binary PBMPLUS/NetPBM
      format (.pgm or .ppm) to PNG; for example,
 
-	wpng -time < toucan.ppm > toucan.png
+        wpng -time < toucan-notrans.ppm > toucan-notrans.png
 
      would convert the specified PPM file (using redirection) to PNG, auto-
      matically setting the PNG modification-time chunk.

contrib/gregbook/readpng.c

@@ -4,13 +4,20 @@
 
   ---------------------------------------------------------------------------
 
-      Copyright (c) 1998-2000 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -27,12 +34,30 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------*/
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <zlib.h>
 
-#include "png.h"        /* libpng header; includes zlib.h */
+#include "png.h"        /* libpng header */
 #include "readpng.h"    /* typedefs, common macros, public prototypes */
 
 /* future versions of libpng will provide this macro: */
@@ -69,7 +94,7 @@ int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight)
      * have used slightly more general png_sig_cmp() function instead */
 
     fread(sig, 1, 8, infile);
-    if (!png_check_sig(sig, 8))
+    if (png_sig_cmp(sig, 0, 8))
         return 1;   /* bad signature */
 
 
@@ -205,8 +230,14 @@ uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
         png_set_expand(png_ptr);
     if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
         png_set_expand(png_ptr);
+#ifdef PNG_READ_16_TO_8_SUPPORTED
     if (bit_depth == 16)
+#  ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+        png_set_scale_16(png_ptr);
+#  else
         png_set_strip_16(png_ptr);
+#  endif
+#endif
     if (color_type == PNG_COLOR_TYPE_GRAY ||
         color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
         png_set_gray_to_rgb(png_ptr);
@@ -239,7 +270,8 @@ uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
         return NULL;
     }
 
-    Trace((stderr, "readpng_get_image:  channels = %d, rowbytes = %ld, height = %ld\n", *pChannels, rowbytes, height));
+    Trace((stderr, "readpng_get_image:  channels = %d, rowbytes = %ld, height = %ld\n",
+        *pChannels, rowbytes, height));
 
 
     /* set the individual row_pointers to point at the correct offsets */

contrib/gregbook/readpng.h

@@ -4,13 +4,20 @@
 
   ---------------------------------------------------------------------------
 
-      Copyright (c) 1998-2000 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -27,6 +34,23 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------*/
 
 #ifndef TRUE

contrib/gregbook/readpng2.c

@@ -4,19 +4,20 @@
 
   ---------------------------------------------------------------------------
 
-   Changelog:
-    - 1.01:  initial public release
-    - 1.02:  added code to skip unused chunks (GR-P)
-
-  ---------------------------------------------------------------------------
-
-      Copyright (c) 1998-2002 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -33,12 +34,31 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------*/
 
 
 #include <stdlib.h>     /* for exit() prototype */
+#include <setjmp.h>
 
-#include "png.h"        /* libpng header; includes zlib.h and setjmp.h */
+#include <zlib.h>
+#include "png.h"        /* libpng header from the local directory */
 #include "readpng2.h"   /* typedefs, common macros, public prototypes */
 
 
@@ -55,79 +75,10 @@ static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg);
 
 void readpng2_version_info(void)
 {
-#if defined(PNG_ASSEMBLER_CODE_SUPPORTED) && \
-    (defined(__i386__) || defined(_M_IX86)) && \
-    defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
-    /*
-     * WARNING:  This preprocessor approach means that the following code
-     *           cannot be used with a libpng DLL older than 1.2.0--the
-     *           compiled-in symbols for the new functions will not exist.
-     *           (Could use dlopen() and dlsym() on Unix and corresponding
-     *           calls for Windows, but not portable...)
-     */
-    {
-        int mmxsupport = png_mmx_support();
-        if (mmxsupport < 0)
-            fprintf(stderr, "   Compiled with libpng %s; using libpng %s "
-              "without MMX support.\n", PNG_LIBPNG_VER_STRING, png_libpng_ver);
-        else {
-            int compilerID;
-            png_uint_32 mmx_mask = png_get_mmx_flagmask(
-              PNG_SELECT_READ | PNG_SELECT_WRITE, &compilerID);
+    fprintf(stderr, "   Compiled with libpng %s; using libpng %s\n",
+      PNG_LIBPNG_VER_STRING, png_libpng_ver);
 
-            fprintf(stderr, "   Compiled with libpng %s; using libpng %s "
-              "with MMX support\n   (%s version).", PNG_LIBPNG_VER_STRING,
-              png_libpng_ver, compilerID == 1? "MSVC++" :
-              (compilerID == 2? "GNU C" : "unknown"));
-            fprintf(stderr, "  Processor %s MMX instructions.\n",
-              mmxsupport? "supports" : "does not support");
-            if (mmxsupport > 0) {
-                int num_optims = 0;
-
-                fprintf(stderr,
-                  "      Potential MMX optimizations supported by libpng:\n");
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_SUB)
-                    ++num_optims;
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_UP)
-                    ++num_optims;
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_AVG)
-                    ++num_optims;
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_FILTER_PAETH)
-                    ++num_optims;
-                if (num_optims)
-                    fprintf(stderr,
-                      "         decoding %s row filters (reading)\n",
-                      (num_optims == 4)? "all non-trivial" : "some");
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW) {
-                    fprintf(stderr, "         combining rows (reading)\n");
-                    ++num_optims;
-                }
-                if (mmx_mask & PNG_ASM_FLAG_MMX_READ_INTERLACE) {
-                    fprintf(stderr,
-                      "         expanding interlacing (reading)\n");
-                    ++num_optims;
-                }
-                mmx_mask &= ~( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
-                             | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
-                             | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
-                             | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
-                             | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
-                             | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH );
-                if (mmx_mask) {
-                    fprintf(stderr, "         other (unknown)\n");
-                    ++num_optims;
-                }
-                if (num_optims == 0)
-                    fprintf(stderr, "         (none)\n");
-            }
-        }
-    }
-#else
-    fprintf(stderr, "   Compiled with libpng %s; using libpng %s "
-      "without MMX support.\n", PNG_LIBPNG_VER_STRING, png_libpng_ver);
-#endif
-
-    fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+    fprintf(stderr, "   and with zlib %s; using zlib %s.\n",
       ZLIB_VERSION, zlib_version);
 }
 
@@ -136,7 +87,7 @@ void readpng2_version_info(void)
 
 int readpng2_check_sig(uch *sig, int num)
 {
-    return png_check_sig(sig, num);
+    return !png_sig_cmp(sig, 0, num);
 }
 
 
@@ -179,40 +130,32 @@ int readpng2_init(mainprog_info *mainprog_ptr)
         return 2;
     }
 
-    /* prepare the reader to ignore all recognized chunks whose data isn't
-     * going to be used, i.e., all chunks recognized by libpng except for
-     * IHDR, PLTE, IDAT, IEND, tRNS, bKGD, gAMA, and sRGB : */
 
-#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+    /* prepare the reader to ignore all recognized chunks whose data won't be
+     * used, i.e., all chunks recognized by libpng except for IHDR, PLTE, IDAT,
+     * IEND, tRNS, bKGD, gAMA, and sRGB (small performance improvement) */
     {
-#ifndef HANDLE_CHUNK_NEVER
-/* prior to libpng-1.2.5, this macro was internal, so we define it here. */
-# define HANDLE_CHUNK_NEVER 1
-#endif
-       /* these byte strings were copied from png.h.
-        * If a future libpng version recognizes more chunks, add them
-        * to this list.  If a future version of readpng2.c recognizes
-        * more chunks, delete them from this list. */
-       png_byte png_chunk_types_to_ignore[]=
-          { 99,  72,  82,  77, '\0', /* cHRM */
-           104,  73,  83,  84, '\0', /* hIST */
-           105,  67,  67,  80, '\0', /* iCCP */
-           105,  84,  88, 116, '\0', /* iTXt */
-           111,  70,  70, 115, '\0', /* oFFs */
-           112,  67,  65,  76, '\0', /* pCAL */
-           115,  67,  65,  76, '\0', /* sCAL */
-           112,  72,  89, 115, '\0', /* pHYs */
-           115,  66,  73,  84, '\0', /* sBIT */
-           115,  80,  76,  84, '\0', /* sPLT */
-           116,  69,  88, 116, '\0', /* tEXt */
-           116,  73,  77,  69, '\0', /* tIME */
-           122,  84,  88, 116, '\0'}; /* zTXt */
-#define NUM_PNG_CHUNK_TYPES_TO_IGNORE 13
+        /* These byte strings were copied from png.h.  If a future version
+         * of readpng2.c recognizes more chunks, add them to this list.
+         */
+        static PNG_CONST png_byte chunks_to_process[] = {
+            98,  75,  71,  68, '\0',  /* bKGD */
+           103,  65,  77,  65, '\0',  /* gAMA */
+           115,  82,  71,  66, '\0',  /* sRGB */
+           };
 
-    png_set_keep_unknown_chunks(png_ptr, HANDLE_CHUNK_NEVER,
-        png_chunk_types_to_ignore, NUM_PNG_CHUNK_TYPES_TO_IGNORE);
+       /* Ignore all chunks except for IHDR, PLTE, tRNS, IDAT, and IEND */
+       png_set_keep_unknown_chunks(png_ptr, -1 /* PNG_HANDLE_CHUNK_NEVER */,
+          NULL, -1);
+
+       /* But do not ignore chunks in the "chunks_to_process" list */
+       png_set_keep_unknown_chunks(png_ptr,
+          0 /* PNG_HANDLE_CHUNK_AS_DEFAULT */, chunks_to_process,
+          sizeof(chunks_to_process)/5);
     }
-#endif
+#endif /* PNG_HANDLE_AS_UNKNOWN_SUPPORTED */
+
 
     /* instead of doing png_init_io() here, now we set up our callback
      * functions for progressive decoding */
@@ -221,96 +164,6 @@ int readpng2_init(mainprog_info *mainprog_ptr)
       readpng2_info_callback, readpng2_row_callback, readpng2_end_callback);
 
 
-    /*
-     * may as well enable or disable MMX routines here, if supported;
-     *
-     * to enable all:  mask = png_get_mmx_flagmask (
-     *                   PNG_SELECT_READ | PNG_SELECT_WRITE, &compilerID);
-     *                 flags = png_get_asm_flags (png_ptr);
-     *                 flags |= mask;
-     *                 png_set_asm_flags (png_ptr, flags);
-     *
-     * to disable all:  mask = png_get_mmx_flagmask (
-     *                   PNG_SELECT_READ | PNG_SELECT_WRITE, &compilerID);
-     *                  flags = png_get_asm_flags (png_ptr);
-     *                  flags &= ~mask;
-     *                  png_set_asm_flags (png_ptr, flags);
-     */
-
-#if (defined(__i386__) || defined(_M_IX86)) && \
-    defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
-    /*
-     * WARNING:  This preprocessor approach means that the following code
-     *           cannot be used with a libpng DLL older than 1.2.0--the
-     *           compiled-in symbols for the new functions will not exist.
-     *           (Could use dlopen() and dlsym() on Unix and corresponding
-     *           calls for Windows, but not portable...)
-     */
-    {
-#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
-        png_uint_32 mmx_disable_mask = 0;
-        png_uint_32 asm_flags, mmx_mask;
-        int compilerID;
-
-        if (mainprog_ptr->nommxfilters)
-            mmx_disable_mask |= ( PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
-                                | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
-                                | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
-                                | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH );
-        if (mainprog_ptr->nommxcombine)
-            mmx_disable_mask |= PNG_ASM_FLAG_MMX_READ_COMBINE_ROW;
-        if (mainprog_ptr->nommxinterlace)
-            mmx_disable_mask |= PNG_ASM_FLAG_MMX_READ_INTERLACE;
-        asm_flags = png_get_asm_flags(png_ptr);
-        png_set_asm_flags(png_ptr, asm_flags & ~mmx_disable_mask);
-
-
-        /* Now query libpng's asm settings, just for yuks.  Note that this
-         * differs from the querying of its *potential* MMX capabilities
-         * in readpng2_version_info(); this is true runtime verification. */
-
-        asm_flags = png_get_asm_flags(png_ptr);
-        mmx_mask = png_get_mmx_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE,
-          &compilerID);
-        if (asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_COMPILED)
-            fprintf(stderr,
-              "  MMX support (%s version) is compiled into libpng\n",
-              compilerID == 1? "MSVC++" :
-              (compilerID == 2? "GNU C" : "unknown"));
-        else
-            fprintf(stderr, "  MMX support is not compiled into libpng\n");
-        fprintf(stderr, "  MMX instructions are %ssupported by CPU\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU)? "" : "not ");
-        fprintf(stderr, "  MMX read support for combining rows is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_COMBINE_ROW)? "en" : "dis");
-        fprintf(stderr,
-          "  MMX read support for expanding interlacing is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_INTERLACE)? "en" : "dis");
-        fprintf(stderr, "  MMX read support for \"sub\" filter is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_SUB)? "en" : "dis");
-        fprintf(stderr, "  MMX read support for \"up\" filter is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_UP)? "en" : "dis");
-        fprintf(stderr, "  MMX read support for \"avg\" filter is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_AVG)? "en" : "dis");
-        fprintf(stderr, "  MMX read support for \"Paeth\" filter is %sabled\n",
-          (asm_flags & PNG_ASM_FLAG_MMX_READ_FILTER_PAETH)? "en" : "dis");
-        asm_flags &= (mmx_mask & ~( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
-                                  | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
-                                  | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
-                                  | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
-                                  | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
-                                  | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ));
-        if (asm_flags)
-            fprintf(stderr,
-              "  additional MMX support is also enabled (0x%02lx)\n",
-              asm_flags);
-#else  /* !PNG_ASSEMBLER_CODE_SUPPORTED */
-        fprintf(stderr, "  MMX querying is disabled in libpng.\n");
-#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
-    }
-#endif
-
-
     /* make sure we save our pointers for use in readpng2_decode_data() */
 
     mainprog_ptr->png_ptr = png_ptr;
@@ -358,7 +211,12 @@ static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)
 {
     mainprog_info  *mainprog_ptr;
     int  color_type, bit_depth;
+    png_uint_32 width, height;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
     double  gamma;
+#else
+    png_fixed_point gamma;
+#endif
 
 
     /* setjmp() doesn't make sense here, because we'd either have to exit(),
@@ -393,8 +251,10 @@ static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)
 
     /* this is just like in the non-progressive case */
 
-    png_get_IHDR(png_ptr, info_ptr, &mainprog_ptr->width,
-      &mainprog_ptr->height, &bit_depth, &color_type, NULL, NULL, NULL);
+    png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+       NULL, NULL, NULL);
+    mainprog_ptr->width = (ulg)width;
+    mainprog_ptr->height = (ulg)height;
 
 
     /* since we know we've read all of the PNG file's "header" (i.e., up
@@ -445,8 +305,14 @@ static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)
         png_set_expand(png_ptr);
     if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
         png_set_expand(png_ptr);
+#ifdef PNG_READ_16_TO_8_SUPPORTED
     if (bit_depth == 16)
+#  ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+        png_set_scale_16(png_ptr);
+#  else
         png_set_strip_16(png_ptr);
+#  endif
+#endif
     if (color_type == PNG_COLOR_TYPE_GRAY ||
         color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
         png_set_gray_to_rgb(png_ptr);
@@ -467,11 +333,19 @@ static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)
      * "gamma" value for the entire display system, i.e., the product of
      * LUT_exponent and CRT_exponent. */
 
+#ifdef PNG_FLOATING_POINT_SUPPORTED
     if (png_get_gAMA(png_ptr, info_ptr, &gamma))
         png_set_gamma(png_ptr, mainprog_ptr->display_exponent, gamma);
     else
         png_set_gamma(png_ptr, mainprog_ptr->display_exponent, 0.45455);
-
+#else
+    if (png_get_gAMA_fixed(png_ptr, info_ptr, &gamma))
+        png_set_gamma_fixed(png_ptr,
+            (png_fixed_point)(100000*mainprog_ptr->display_exponent+.5), gamma);
+    else
+        png_set_gamma_fixed(png_ptr,
+            (png_fixed_point)(100000*mainprog_ptr->display_exponent+.5), 45455);
+#endif
 
     /* we'll let libpng expand interlaced images, too */
 
@@ -620,5 +494,12 @@ static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg)
         exit(99);
     }
 
+    /* Now we have our data structure we can use the information in it
+     * to return control to our own higher level code (all the points
+     * where 'setjmp' is called in this file.)  This will work with other
+     * error handling mechanisms as well - libpng always calls png_error
+     * when it can proceed no further, thus, so long as the error handler
+     * is intercepted, application code can do its own error recovery.
+     */
     longjmp(mainprog_ptr->jmpbuf, 1);
 }

contrib/gregbook/readpng2.h

@@ -4,13 +4,20 @@
 
   ---------------------------------------------------------------------------
 
-      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -27,6 +34,23 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------*/
 
 #ifndef TRUE
@@ -45,6 +69,12 @@
 #  define Trace(x)  ;
 #endif
 
+enum rpng2_states {
+    kPreInit = 0,
+    kWindowInit,
+    kDone
+};
+
 typedef unsigned char   uch;
 typedef unsigned short  ush;
 typedef unsigned long   ulg;
@@ -66,12 +96,7 @@ typedef struct _mainprog_info {
     int rowbytes;
     int channels;
     int need_bgcolor;
-#if (defined(__i386__) || defined(_M_IX86))
-    int nommxfilters;
-    int nommxcombine;
-    int nommxinterlace;
-#endif
-    int done;
+    int state;
     uch bg_red;
     uch bg_green;
     uch bg_blue;

contrib/gregbook/readppm.c

@@ -0,0 +1,179 @@
+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                              readppm.c
+
+  ---------------------------------------------------------------------------
+
+   This is a special-purpose replacement for readpng.c that allows binary
+   PPM files to be used in place of PNG images.
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+  ---------------------------------------------------------------------------*/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "readpng.h"    /* typedefs, common macros, public prototypes */
+
+
+ulg  width, height;
+int  bit_depth, color_type, channels;
+uch  *image_data = NULL;
+FILE *saved_infile;
+
+
+void readpng_version_info()
+{
+    fprintf(stderr, "   Compiled without libpng, zlib or PBMPLUS/NetPBM.\n");
+}
+
+
+/* return value = 0 for success, 1 for bad sig, 2 for bad IHDR, 4 for no mem */
+
+int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight)
+{
+    static uch ppmline[256];
+    int maxval;
+
+
+    saved_infile = infile;
+
+    fgets(ppmline, 256, infile);
+    if (ppmline[0] != 'P' || ppmline[1] != '6') {
+        fprintf(stderr, "ERROR:  not a PPM file\n");
+        return 1;
+    }
+    /* possible color types:  P5 = grayscale (0), P6 = RGB (2), P8 = RGBA (6) */
+    if (ppmline[1] == '6') {
+        color_type = 2;
+        channels = 3;
+    } else if (ppmline[1] == '8') {
+        color_type = 6;
+        channels = 4;
+    } else /* if (ppmline[1] == '5') */ {
+        color_type = 0;
+        channels = 1;
+    }
+
+    do {
+        fgets(ppmline, 256, infile);
+    } while (ppmline[0] == '#');
+    sscanf(ppmline, "%lu %lu", &width, &height);
+
+    do {
+        fgets(ppmline, 256, infile);
+    } while (ppmline[0] == '#');
+    sscanf(ppmline, "%d", &maxval);
+    if (maxval != 255) {
+        fprintf(stderr, "ERROR:  maxval = %d\n", maxval);
+        return 2;
+    }
+    bit_depth = 8;
+
+    *pWidth = width;
+    *pHeight = height;
+
+    return 0;
+}
+
+
+
+
+/* returns 0 if succeeds, 1 if fails due to no bKGD chunk, 2 if libpng error;
+ * scales values to 8-bit if necessary */
+
+int readpng_get_bgcolor(uch *red, uch *green, uch *blue)
+{
+    return 1;
+}
+
+
+
+
+/* display_exponent == LUT_exponent * CRT_exponent */
+
+uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
+{
+    ulg  rowbytes;
+
+
+    /* expand palette images to RGB, low-bit-depth grayscale images to 8 bits,
+     * transparency chunks to full alpha channel; strip 16-bit-per-sample
+     * images to 8 bits per sample; and convert grayscale to RGB[A] */
+
+    /* GRR WARNING:  grayscale needs to be expanded and channels reset! */
+
+    *pRowbytes = rowbytes = channels*width;
+    *pChannels = channels;
+
+    if ((image_data = (uch *)malloc(rowbytes*height)) == NULL) {
+        return NULL;
+    }
+
+    Trace((stderr, "readpng_get_image:  rowbytes = %ld, height = %ld\n", rowbytes, height));
+
+
+    /* now we can go ahead and just read the whole image */
+
+    fread(image_data, 1L, rowbytes*height, saved_infile);
+
+
+    return image_data;
+}
+
+
+void readpng_cleanup(int free_image_data)
+{
+    if (free_image_data && image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+}

contrib/gregbook/rpng-win.c

@@ -22,16 +22,25 @@
     - 1.02:  added extra set of parentheses to png_jmpbuf() macro; fixed
               command-line parsing bug
     - 1.10:  enabled "message window"/console (thanks to David Geldreich)
+    - 2.00:  dual-licensed (added GNU GPL)
+    - 2.01:  fixed improper display of usage screen on PNG error(s)
 
   ---------------------------------------------------------------------------
 
-      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -48,18 +57,61 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------*/
 
 #define PROGNAME  "rpng-win"
 #define LONGNAME  "Simple PNG Viewer for Windows"
-#define VERSION   "1.20 of 28 May 2001"
+#define VERSION   "2.01 of 16 March 2008"
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
 #include <windows.h>
+#ifdef __CYGWIN__
+/* getch replacement. Turns out, we don't really need this,
+ * but leave it here if we ever enable any of the uses of
+ * _getch in the main code
+ */
+#include <unistd.h>
+#include <termio.h>
+#include <sys/ioctl.h>
+int repl_getch( void )
+{
+  char ch;
+  int fd = fileno(stdin);
+  struct termio old_tty, new_tty;
+
+  ioctl(fd, TCGETA, &old_tty);
+  new_tty = old_tty;
+  new_tty.c_lflag &= ~(ICANON | ECHO | ISIG);
+  ioctl(fd, TCSETA, &new_tty);
+  fread(&ch, 1, sizeof(ch), stdin);
+  ioctl(fd, TCSETA, &old_tty);
+
+  return ch;
+}
+#define _getch repl_getch
+#else
 #include <conio.h>      /* only for _getch() */
+#endif
 
 /* #define DEBUG  :  this enables the Trace() macros */
 
@@ -85,10 +137,9 @@ static void       rpng_win_cleanup(void);
 LRESULT CALLBACK  rpng_win_wndproc(HWND, UINT, WPARAM, LPARAM);
 
 
-static char titlebar[1024], *window_name = titlebar;
+static char titlebar[1024];
 static char *progname = PROGNAME;
 static char *appname = LONGNAME;
-static char *icon_name = PROGNAME;     /* GRR:  not (yet) used */
 static char *filename;
 static FILE *infile;
 
@@ -128,7 +179,7 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
 
     filename = (char *)NULL;
 
-
+#ifndef __CYGWIN__
     /* First reenable console output, which normally goes to the bit bucket
      * for windowed apps.  Closing the console window will terminate the
      * app.  Thanks to David.Geldreich@realviz.com for supplying the magical
@@ -137,6 +188,7 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
     AllocConsole();
     freopen("CONOUT$", "a", stderr);
     freopen("CONOUT$", "a", stdout);
+#endif
 
 
     /* Next set the default value for our display-system exponent, i.e.,
@@ -247,9 +299,43 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
         }
     }
 
-    if (!filename) {
+    if (!filename)
         ++error;
-    } else if (!(infile = fopen(filename, "rb"))) {
+
+
+    /* print usage screen if any errors up to this point */
+
+    if (error) {
+#ifndef __CYGWIN__
+        int ch;
+#endif
+
+        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);
+        readpng_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-gamma exp] [-bgcolor bg] file.png\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images\n"
+          "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
+#ifndef __CYGWIN__
+          "Press Q or Esc to quit this usage screen.\n"
+#endif
+          "\n", PROGNAME, default_display_exponent);
+#ifndef __CYGWIN__
+        do
+            ch = _getch();
+        while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+#endif
+        exit(1);
+    }
+
+
+    if (!(infile = fopen(filename, "rb"))) {
         fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
         ++error;
     } else {
@@ -262,8 +348,7 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
                     break;
                 case 2:
                     fprintf(stderr, PROGNAME
-                      ":  [%s] has bad IHDR (libpng longjmp)\n",
-                      filename);
+                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);
                     break;
                 case 4:
                     fprintf(stderr, PROGNAME ":  insufficient memory\n");
@@ -280,34 +365,25 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
     }
 
 
-    /* usage screen */
-
     if (error) {
+#ifndef __CYGWIN__
         int ch;
+#endif
 
-        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);
-        readpng_version_info();
-        fprintf(stderr, "\n"
-          "Usage:  %s [-gamma exp] [-bgcolor bg] file.png\n"
-          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
-          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
-          "\t\t  to the product of the lookup-table exponent (varies)\n"
-          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
-          "    bg  \tdesired background color in 7-character hex RGB format\n"
-          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
-          "\t\t  used with transparent images\n"
-          "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
-          "Press Q or Esc to quit this usage screen.\n"
-          "\n", PROGNAME, default_display_exponent);
+        fprintf(stderr, PROGNAME ":  aborting.\n");
+#ifndef __CYGWIN__
         do
             ch = _getch();
         while (ch != 'q' && ch != 'Q' && ch != 0x1B);
-        exit(1);
+#endif
+        exit(2);
     } else {
         fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+#ifndef __CYGWIN__
         fprintf(stderr,
           "\n   [console window:  closing this window will terminate %s]\n\n",
           PROGNAME);
+#endif
     }
 
 
@@ -325,9 +401,14 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
      * check for one in the PNG file--if not, the initialized values of 0
      * (black) will be used */
 
-    if (have_bg)
-        sscanf(bgstr+1, "%2x%2x%2x", &bg_red, &bg_green, &bg_blue);
-    else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {
+    if (have_bg) {
+        unsigned r, g, b;   /* this approach quiets compiler warnings */
+
+        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+        bg_red   = (uch)r;
+        bg_green = (uch)g;
+        bg_blue  = (uch)b;
+    } else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {
         readpng_cleanup(TRUE);
         fprintf(stderr, PROGNAME
           ":  libpng error while checking for background color\n");
@@ -375,7 +456,12 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
     /* wait for the user to tell us when to quit */
 
     printf(
-      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n");
+#ifndef __CYGWIN__
+      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n"
+#else
+      "Done.  Press mouse button 1 (within image window) to quit.\n"
+#endif
+    );
     fflush(stdout);
 
     while (GetMessage(&msg, NULL, 0, 0)) {

contrib/gregbook/rpng-x.c

@@ -9,7 +9,7 @@
    by Martin Zinser under OpenVMS; may work under OS/2 with some tweaking).
 
    to do:
-    - 8-bit support
+    - 8-bit (colormapped) X support
     - use %.1023s to simplify truncation of title-bar string?
 
   ---------------------------------------------------------------------------
@@ -21,18 +21,28 @@
     - 1.10:  added support for non-default visuals; fixed X pixel-conversion
     - 1.11:  added extra set of parentheses to png_jmpbuf() macro; fixed
               command-line parsing bug
-    - 1.12:  fixed small X memory leak (thanks to Francois Petitjean)
-    - 1.13:  fixed XFreeGC() crash bug
+    - 1.12:  fixed some small X memory leaks (thanks to Fran<EFBFBD>ois Petitjean)
+    - 1.13:  fixed XFreeGC() crash bug (thanks to Patrick Welche)
+    - 1.14:  added support for X resources (thanks to Gerhard Niklasch)
+    - 2.00:  dual-licensed (added GNU GPL)
+    - 2.01:  fixed improper display of usage screen on PNG error(s)
 
   ---------------------------------------------------------------------------
 
-      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -49,11 +59,30 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------*/
 
 #define PROGNAME  "rpng-x"
 #define LONGNAME  "Simple PNG Viewer for X"
-#define VERSION   "1.13 of 16 August 2001"
+#define VERSION   "2.01 of 16 March 2008"
+#define RESNAME   "rpng"        /* our X resource application name */
+#define RESCLASS  "Rpng"        /* our X resource class name */
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -91,6 +120,8 @@ static int  rpng_x_msb(ulg u32val);
 static char titlebar[1024], *window_name = titlebar;
 static char *appname = LONGNAME;
 static char *icon_name = PROGNAME;
+static char *res_name = RESNAME;
+static char *res_class = RESCLASS;
 static char *filename;
 static FILE *infile;
 
@@ -235,9 +266,33 @@ int main(int argc, char **argv)
         }
     }
 
-    if (!filename) {
+    if (!filename)
         ++error;
-    } else if (!(infile = fopen(filename, "rb"))) {
+
+
+    /* print usage screen if any errors up to this point */
+
+    if (error) {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+        readpng_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-display xdpy] [-gamma exp] [-bgcolor bg] file.png\n"
+          "    xdpy\tname of the target X display (e.g., ``hostname:0'')\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images\n"
+          "\nPress Q, Esc or mouse button 1 (within image window, after image\n"
+          "is displayed) to quit.\n"
+          "\n", PROGNAME, default_display_exponent);
+        exit(1);
+    }
+
+
+    if (!(infile = fopen(filename, "rb"))) {
         fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
         ++error;
     } else {
@@ -250,8 +305,7 @@ int main(int argc, char **argv)
                     break;
                 case 2:
                     fprintf(stderr, PROGNAME
-                      ":  [%s] has bad IHDR (libpng longjmp)\n",
-                      filename);
+                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);
                     break;
                 case 4:
                     fprintf(stderr, PROGNAME ":  insufficient memory\n");
@@ -276,25 +330,9 @@ int main(int argc, char **argv)
     }
 
 
-    /* usage screen */
-
     if (error) {
-        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
-        readpng_version_info();
-        fprintf(stderr, "\n"
-          "Usage:  %s [-display xdpy] [-gamma exp] [-bgcolor bg] file.png\n"
-          "    xdpy\tname of the target X display (e.g., ``hostname:0'')\n"
-          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
-          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
-          "\t\t  to the product of the lookup-table exponent (varies)\n"
-          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
-          "    bg  \tdesired background color in 7-character hex RGB format\n"
-          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
-          "\t\t  used with transparent images\n"
-          "\nPress Q, Esc or mouse button 1 (within image window, after image\n"
-          "is displayed) to quit.\n"
-          "\n", PROGNAME, default_display_exponent);
-        exit(1);
+        fprintf(stderr, PROGNAME ":  aborting.\n");
+        exit(2);
     }
 
 
@@ -399,11 +437,12 @@ static int rpng_x_create_window(void)
     XEvent e;
     XGCValues gcvalues;
     XSetWindowAttributes attr;
-    XSizeHints *size_hints;
     XTextProperty windowName, *pWindowName = &windowName;
     XTextProperty iconName, *pIconName = &iconName;
     XVisualInfo visual_info;
+    XSizeHints *size_hints;
     XWMHints *wm_hints;
+    XClassHint *class_hints;
 
 
     screen = DefaultScreen(display);
@@ -526,7 +565,7 @@ static int rpng_x_create_window(void)
     if (!XStringListToTextProperty(&icon_name, 1, pIconName))
         pIconName = NULL;
 
-    /* OK if either hints allocation fails; XSetWMProperties() allows NULLs */
+    /* OK if any hints allocation fails; XSetWMProperties() allows NULLs */
 
     if ((size_hints = XAllocSizeHints()) != NULL) {
         /* window will not be resizable */
@@ -542,8 +581,13 @@ static int rpng_x_create_window(void)
         wm_hints->flags = StateHint | InputHint  /* | IconPixmapHint */ ;
     }
 
+    if ((class_hints = XAllocClassHint()) != NULL) {
+        class_hints->res_name = res_name;
+        class_hints->res_class = res_class;
+    }
+
     XSetWMProperties(display, window, pWindowName, pIconName, NULL, 0,
-      size_hints, wm_hints, NULL);
+      size_hints, wm_hints, class_hints);
 
     /* various properties and hints no longer needed; free memory */
     if (pWindowName)
@@ -554,6 +598,8 @@ static int rpng_x_create_window(void)
         XFree(size_hints);
     if (wm_hints)
        XFree(wm_hints);
+    if (class_hints)
+       XFree(class_hints);
 
     XMapWindow(display, window);
 

contrib/gregbook/rpng2-win.c

@@ -10,7 +10,7 @@
    tweaking (or maybe not).  Thanks to Adam Costello and Pieter S. van der
    Meulen for the "diamond" and "radial waves" patterns, respectively.
 
-   to do:
+   to do (someday, maybe):
     - handle quoted command-line args (especially filenames with spaces)
     - finish resizable checkerboard-gradient (sizes 4-128?)
     - use %.1023s to simplify truncation of title-bar string?
@@ -27,16 +27,29 @@
     - 1.10:  enabled "message window"/console (thanks to David Geldreich)
     - 1.20:  added runtime MMX-enabling/disabling and new -mmx* options
     - 1.21:  made minor tweak to usage screen to fit within 25-line console
+    - 1.22:  added AMD64/EM64T support (__x86_64__)
+    - 2.00:  dual-licensed (added GNU GPL)
+    - 2.01:  fixed 64-bit typo in readpng2.c
+    - 2.02:  fixed improper display of usage screen on PNG error(s); fixed
+              unexpected-EOF and file-read-error cases
+    - 2.03:  removed runtime MMX-enabling/disabling and obsolete -mmx* options
 
   ---------------------------------------------------------------------------
 
-      Copyright (c) 1998-2001 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2008 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -53,11 +66,28 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------*/
 
 #define PROGNAME  "rpng2-win"
 #define LONGNAME  "Progressive PNG Viewer for Windows"
-#define VERSION   "1.21 of 29 June 2001"
+#define VERSION   "2.02 of 16 March 2008"
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -66,7 +96,33 @@
 #include <time.h>
 #include <math.h>      /* only for PvdM background code */
 #include <windows.h>
+#ifdef __CYGWIN__
+/* getch replacement. Turns out, we don't really need this,
+ * but leave it here if we ever enable any of the uses of
+ * _getch in the main code
+ */
+#include <unistd.h>
+#include <termio.h>
+#include <sys/ioctl.h>
+int repl_getch( void )
+{
+  char ch;
+  int fd = fileno(stdin);
+  struct termio old_tty, new_tty;
+
+  ioctl(fd, TCGETA, &old_tty);
+  new_tty = old_tty;
+  new_tty.c_lflag &= ~(ICANON | ECHO | ISIG);
+  ioctl(fd, TCSETA, &new_tty);
+  fread(&ch, 1, sizeof(ch), stdin);
+  ioctl(fd, TCSETA, &old_tty);
+
+  return ch;
+}
+#define _getch repl_getch
+#else
 #include <conio.h>     /* only for _getch() */
+#endif
 
 /* all for PvdM background code: */
 #ifndef PI
@@ -119,10 +175,9 @@ static void       rpng2_win_cleanup(void);
 LRESULT CALLBACK  rpng2_win_wndproc(HWND, UINT, WPARAM, LPARAM);
 
 
-static char titlebar[1024], *window_name = titlebar;
+static char titlebar[1024];
 static char *progname = PROGNAME;
 static char *appname = LONGNAME;
-static char *icon_name = PROGNAME;    /* GRR:  not (yet) used */
 static char *filename;
 static FILE *infile;
 
@@ -241,7 +296,7 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
     filename = (char *)NULL;
     memset(&rpng2_info, 0, sizeof(mainprog_info));
 
-
+#ifndef __CYGWIN__
     /* Next reenable console output, which normally goes to the bit bucket
      * for windowed apps.  Closing the console window will terminate the
      * app.  Thanks to David.Geldreich@realviz.com for supplying the magical
@@ -250,7 +305,7 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
     AllocConsole();
     freopen("CONOUT$", "a", stderr);
     freopen("CONOUT$", "a", stdout);
-
+#endif
 
     /* Set the default value for our display-system exponent, i.e., the
      * product of the CRT exponent and the exponent corresponding to
@@ -367,18 +422,6 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
             }
         } else if (!strncmp(*argv, "-timing", 2)) {
             timing = TRUE;
-#if (defined(__i386__) || defined(_M_IX86))
-        } else if (!strncmp(*argv, "-nommxfilters", 7)) {
-            rpng2_info.nommxfilters = TRUE;
-        } else if (!strncmp(*argv, "-nommxcombine", 7)) {
-            rpng2_info.nommxcombine = TRUE;
-        } else if (!strncmp(*argv, "-nommxinterlace", 7)) {
-            rpng2_info.nommxinterlace = TRUE;
-        } else if (!strcmp(*argv, "-nommx")) {
-            rpng2_info.nommxfilters = TRUE;
-            rpng2_info.nommxcombine = TRUE;
-            rpng2_info.nommxinterlace = TRUE;
-#endif
         } else {
             if (**argv != '-') {
                 filename = *argv;
@@ -389,9 +432,56 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
         }
     }
 
-    if (!filename) {
+    if (!filename)
         ++error;
-    } else if (!(infile = fopen(filename, "rb"))) {
+
+
+    /* print usage screen if any errors up to this point */
+
+    if (error) {
+#ifndef __CYGWIN__
+        int ch;
+#endif
+
+        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);
+        readpng2_version_info();
+        fprintf(stderr, "\n"
+          "Usage:  %s [-gamma exp] [-bgcolor bg | -bgpat pat] [-timing]\n"
+          "        %*s file.png\n\n"
+          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+          "\t\t  to the product of the lookup-table exponent (varies)\n"
+          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+          "    bg  \tdesired background color in 7-character hex RGB format\n"
+          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
+          "\t\t  used with transparent images; overrides -bgpat option\n"
+          "    pat \tdesired background pattern number (1-%d); used with\n"
+          "\t\t  transparent images; overrides -bgcolor option\n"
+          "    -timing\tenables delay for every block read, to simulate modem\n"
+          "\t\t  download of image (~36 Kbps)\n"
+          "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
+#ifndef __CYGWIN__
+          "Press Q or Esc to quit this usage screen. ",
+#else
+          ,
+#endif
+          PROGNAME,
+#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__)) && \
+    !(defined(__CYGWIN__) || defined(__MINGW32__))
+          (int)strlen(PROGNAME), " ",
+#endif
+          (int)strlen(PROGNAME), " ", default_display_exponent, num_bgpat);
+        fflush(stderr);
+#ifndef __CYGWIN__
+        do
+            ch = _getch();
+        while (ch != 'q' && ch != 'Q' && ch != 0x1B);
+#endif
+        exit(1);
+    }
+
+
+    if (!(infile = fopen(filename, "rb"))) {
         fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
         ++error;
     } else {
@@ -405,8 +495,7 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
             switch (rc) {
                 case 2:
                     fprintf(stderr, PROGNAME
-                      ":  [%s] has bad IHDR (libpng longjmp)\n",
-                      filename);
+                      ":  [%s] has bad IHDR (libpng longjmp)\n", filename);
                     break;
                 case 4:
                     fprintf(stderr, PROGNAME ":  insufficient memory\n");
@@ -423,51 +512,25 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
     }
 
 
-    /* usage screen */
-
     if (error) {
+#ifndef __CYGWIN__
         int ch;
+#endif
 
-        fprintf(stderr, "\n%s %s:  %s\n\n", PROGNAME, VERSION, appname);
-        readpng2_version_info();
-        fprintf(stderr, "\n"
-          "Usage:  %s [-gamma exp] [-bgcolor bg | -bgpat pat] [-timing]\n"
-#if (defined(__i386__) || defined(_M_IX86))
-          "        %*s [[-nommxfilters] [-nommxcombine] [-nommxinterlace] | -nommx]\n"
-#endif
-          "        %*s file.png\n\n"
-          "    exp \ttransfer-function exponent (``gamma'') of the display\n"
-          "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
-          "\t\t  to the product of the lookup-table exponent (varies)\n"
-          "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
-          "    bg  \tdesired background color in 7-character hex RGB format\n"
-          "\t\t  (e.g., ``#ff7700'' for orange:  same as HTML colors);\n"
-          "\t\t  used with transparent images; overrides -bgpat option\n"
-          "    pat \tdesired background pattern number (1-%d); used with\n"
-          "\t\t  transparent images; overrides -bgcolor option\n"
-          "    -timing\tenables delay for every block read, to simulate modem\n"
-          "\t\t  download of image (~36 Kbps)\n"
-#if (defined(__i386__) || defined(_M_IX86))
-          "    -nommx*\tdisable optimized MMX routines for decoding row filters,\n"
-          "\t\t  combining rows, and expanding interlacing, respectively\n"
-#endif
-          "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
-          "Press Q or Esc to quit this usage screen. ",
-          PROGNAME,
-#if (defined(__i386__) || defined(_M_IX86))
-          strlen(PROGNAME), " ",
-#endif
-          strlen(PROGNAME), " ", default_display_exponent, num_bgpat);
-        fflush(stderr);
+        fprintf(stderr, PROGNAME ":  aborting.\n");
+#ifndef __CYGWIN__
         do
             ch = _getch();
         while (ch != 'q' && ch != 'Q' && ch != 0x1B);
-        exit(1);
+#endif
+        exit(2);
     } else {
         fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+#ifndef __CYGWIN__
         fprintf(stderr,
           "\n   [console window:  closing this window will terminate %s]\n\n",
           PROGNAME);
+#endif
         fflush(stderr);
     }
 
@@ -494,7 +557,7 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
     } else
         rpng2_info.need_bgcolor = TRUE;
 
-    rpng2_info.done = FALSE;
+    rpng2_info.state = kPreInit;
     rpng2_info.mainprog_init = rpng2_win_init;
     rpng2_info.mainprog_display_row = rpng2_win_display_row;
     rpng2_info.mainprog_finish_display = rpng2_win_finish_display;
@@ -514,10 +577,27 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
         if (readpng2_decode_data(&rpng2_info, inbuf, incount))
             ++error;
         Trace((stderr, "done with readpng2_decode_data()\n"))
-        if (error || feof(infile) || rpng2_info.done)
+
+        if (error || incount != INBUFSIZE || rpng2_info.state == kDone) {
+            if (rpng2_info.state == kDone) {
+                Trace((stderr, "done decoding PNG image\n"))
+            } else if (ferror(infile)) {
+                fprintf(stderr, PROGNAME
+                  ":  error while reading PNG image file\n");
+                exit(3);
+            } else if (feof(infile)) {
+                fprintf(stderr, PROGNAME ":  end of file reached "
+                  "(unexpectedly) while reading PNG image file\n");
+                exit(3);
+            } else /* if (error) */ {
+                /* will print error message below */
+            }
             break;
+        }
+
         if (timing)
             Sleep(1000L);
+
         incount = fread(inbuf, 1, INBUFSIZE, infile);
     }
 
@@ -564,7 +644,7 @@ static void rpng2_win_init()
     ulg rowbytes = rpng2_info.rowbytes;
 
     Trace((stderr, "beginning rpng2_win_init()\n"))
-    Trace((stderr, "  rowbytes = %ld\n", rpng2_info.rowbytes))
+    Trace((stderr, "  rowbytes = %d\n", rpng2_info.rowbytes))
     Trace((stderr, "  width  = %ld\n", rpng2_info.width))
     Trace((stderr, "  height = %ld\n", rpng2_info.height))
 
@@ -594,6 +674,8 @@ static void rpng2_win_init()
         readpng2_cleanup(&rpng2_info);
         return;
     }
+
+    rpng2_info.state = kWindowInit;
 }
 
 
@@ -1089,9 +1171,14 @@ static void rpng2_win_finish_display()
      * we have nothing to do here except set a flag and let the user know
      * that the image is done */
 
-    rpng2_info.done = TRUE;
+    rpng2_info.state = kDone;
     printf(
-      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n");
+#ifndef __CYGWIN__
+      "Done.  Press Q, Esc or mouse button 1 (within image window) to quit.\n"
+#else
+      "Done.  Press mouse button 1 (within image window) to quit.\n"
+#endif
+    );
     fflush(stdout);
 }
 

contrib/gregbook/wpng.c

@@ -5,8 +5,10 @@
    This program converts certain NetPBM binary files (grayscale and RGB,
    maxval = 255) to PNG.  Non-interlaced PNGs are written progressively;
    interlaced PNGs are read and written in one memory-intensive blast.
+
    Thanks to Jean-loup Gailly for providing the necessary trick to read
-   interactive text from the keyboard while stdin is redirected.
+   interactive text from the keyboard while stdin is redirected.  Thanks
+   to Cosmin Truta for Cygwin fixes.
 
    NOTE:  includes provisional support for PNM type "8" (portable alphamap)
           images, presumed to be a 32-bit interleaved RGBA format; no pro-
@@ -24,16 +26,32 @@
     - 1.02:  modified to allow abbreviated options
     - 1.03:  removed extraneous character from usage screen; fixed bug in
               command-line parsing
+    - 1.04:  fixed DOS/OS2/Win32 detection, including partial Cygwin fix
+              (see http://home.att.net/~perlspinr/diffs/GregBook_cygwin.diff)
+    - 2.00:  dual-licensed (added GNU GPL)
+
+        [REPORTED BUG (win32 only):  "contrib/gregbook/wpng.c - cmd line
+         dose not work!  In order to do something useful I needed to redirect
+         both input and output, with cygwin and with bcc32 as well.  Under
+         Linux, the same wpng appears to work fine.  I don't know what is
+         the problem."]
 
   ---------------------------------------------------------------------------
 
-      Copyright (c) 1998-2000 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -50,16 +68,35 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------*/
 
 #define PROGNAME  "wpng"
-#define VERSION   "1.03 of 19 March 2000"
+#define VERSION   "2.00 of 2 June 2007"
 #define APPNAME   "Simple PGM/PPM/PAM to PNG Converter"
 
 #if defined(__MSDOS__) || defined(__OS2__)
 #  define DOS_OS2_W32
-#elif defined(_WIN32) || defined(__WIN32__)
+#elif defined(WIN32) || defined(_WIN32) || defined(__WIN32__)
+#  ifndef __GNUC__   /* treat Win32 native ports of gcc as Unix environments */
 #    define DOS_OS2_W32
+#  endif
 #endif
 
 #include <stdio.h>

contrib/gregbook/writepng.c

@@ -4,13 +4,20 @@
 
   ---------------------------------------------------------------------------
 
-      Copyright (c) 1998-2000 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -27,12 +34,30 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------*/
 
 
 #include <stdlib.h>     /* for exit() prototype */
+#include <zlib.h>
 
-#include "png.h"        /* libpng header; includes zlib.h and setjmp.h */
+#include "png.h"        /* libpng header, includes setjmp.h */
 #include "writepng.h"   /* typedefs, common macros, public prototypes */
 
 
@@ -80,7 +105,8 @@ int writepng_init(mainprog_info *mainprog_ptr)
     /* setjmp() must be called in every function that calls a PNG-writing
      * libpng function, unless an alternate error handler was installed--
      * but compatible error handlers must either use longjmp() themselves
-     * (as in this program) or exit immediately, so here we go: */
+     * (as in this program) or some other method to return control to
+     * application code, so here we go: */
 
     if (setjmp(mainprog_ptr->jmpbuf)) {
         png_destroy_write_struct(&png_ptr, &info_ptr);
@@ -364,5 +390,12 @@ static void writepng_error_handler(png_structp png_ptr, png_const_charp msg)
         exit(99);
     }
 
+    /* Now we have our data structure we can use the information in it
+     * to return control to our own higher level code (all the points
+     * where 'setjmp' is called in this file.)  This will work with other
+     * error handling mechanisms as well - libpng always calls png_error
+     * when it can proceed no further, thus, so long as the error handler
+     * is intercepted, application code can do its own error recovery.
+     */
     longjmp(mainprog_ptr->jmpbuf, 1);
 }

contrib/gregbook/writepng.h

@@ -4,13 +4,20 @@
 
   ---------------------------------------------------------------------------
 
-      Copyright (c) 1998-2000 Greg Roelofs.  All rights reserved.
+      Copyright (c) 1998-2007 Greg Roelofs.  All rights reserved.
 
       This software is provided "as is," without warranty of any kind,
       express or implied.  In no event shall the author or contributors
       be held liable for any damages arising in any way from the use of
       this software.
 
+      The contents of this file are DUAL-LICENSED.  You may modify and/or
+      redistribute this software according to the terms of one of the
+      following two licenses (at your option):
+
+
+      LICENSE 1 ("BSD-like with advertising clause"):
+
       Permission is granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute
       it freely, subject to the following restrictions:
@@ -27,6 +34,23 @@
             and contributors for the book, "PNG: The Definitive Guide,"
             published by O'Reilly and Associates.
 
+
+      LICENSE 2 (GNU GPL v2 or later):
+
+      This program is free software; you can redistribute it and/or modify
+      it under the terms of the GNU General Public License as published by
+      the Free Software Foundation; either version 2 of the License, or
+      (at your option) any later version.
+
+      This program is distributed in the hope that it will be useful,
+      but WITHOUT ANY WARRANTY; without even the implied warranty of
+      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+      GNU General Public License for more details.
+
+      You should have received a copy of the GNU General Public License
+      along with this program; if not, write to the Free Software Foundation,
+      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
   ---------------------------------------------------------------------------*/
 
 #ifndef TRUE

contrib/libtests/fakepng.c

@@ -0,0 +1,57 @@
+/* Fake a PNG - just write it out directly. */
+#include <stdio.h>
+#include <zlib.h> /* for crc32 */
+
+void
+put_uLong(uLong val)
+{
+   putchar(val >> 24);
+   putchar(val >> 16);
+   putchar(val >>  8);
+   putchar(val >>  0);
+}
+
+void
+put_chunk(const unsigned char *chunk, uInt length)
+{
+   uLong crc;
+
+   put_uLong(length-4); /* Exclude the tag */
+
+   fwrite(chunk, length, 1, stdout);
+
+   crc = crc32(0, Z_NULL, 0);
+   put_uLong(crc32(crc, chunk, length));
+}
+
+const unsigned char signature[] =
+{
+   137, 80, 78, 71, 13, 10, 26, 10
+};
+
+const unsigned char IHDR[] =
+{
+   73, 72, 68, 82, /* IHDR */
+   0, 0, 0, 1, /* width */
+   0, 0, 0, 1, /* height */
+   1, /* bit depth */
+   0, /* color type: greyscale */
+   0, /* compression method */
+   0, /* filter method */
+   0  /* interlace method: none */
+};
+
+const unsigned char unknown[] =
+{
+   'u', 'n', 'K', 'n' /* "unKn" - private safe to copy */
+};
+
+int
+main(void)
+{
+   fwrite(signature, sizeof signature, 1, stdout);
+   put_chunk(IHDR, sizeof IHDR);
+
+   for(;;)
+      put_chunk(unknown, sizeof unknown);
+}

contrib/libtests/gentests.sh

@@ -0,0 +1,102 @@
+#!/bin/sh
+#
+# Copyright (c) 2012 John Cunningham Bowler
+#
+# Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+#
+# Generate a set of PNG test images.  The images are generated in a
+# sub-directory called 'tests' by default, however a command line argument will
+# change that name.  The generation requires a built version of makepng in the
+# current directory.
+#
+usage(){
+   exec >&2
+   echo "$0 [<directory>]"
+   echo '  Generate a set of PNG test files in "directory" ("tests" by default)'
+   exit 1
+}
+
+mp="$PWD/makepng"
+test -x "$mp" || {
+   exec >&2
+   echo "$0: the 'makepng' program must exist"
+   echo "  in the directory within which this program:"
+   echo "    $mp"
+   echo "  is executed"
+   usage
+}
+
+# Just one argument: the directory
+testdir="tests"
+test $# -gt 1 && {
+   testdir="$1"
+   shift
+}
+test $# -eq 0 || usage
+
+# Take care not to clobber something
+if test -e "$testdir"
+then
+   test -d "$testdir" || usage
+else
+   # mkdir -p isn't portable, so do the following
+   mkdir "$testdir" 2>/dev/null || mkdir -p "$testdir" || usage
+fi
+
+# This fails in a very satisfactory way if it's not accessible
+cd "$testdir"
+:>"test$$.png" || {
+   exec >&2
+   echo "$testdir: directory not writable"
+   usage
+}
+rm "test$$.png" || {
+   exec >&2
+   echo "$testdir: you have create but not write privileges here."
+   echo "  This is unexpected.  You have a spurion; "'"'"test$$.png"'"'"."
+   echo "  You need to remove this yourself.  Try a different directory."
+   exit 1
+}
+
+# Now call makepng ($mp) to create every file we can think of with a
+# reasonable name
+doit(){
+   for gamma in "" --sRGB --linear --1.8
+   do
+      case "$gamma" in
+         "")
+            gname=;;
+         --sRGB)
+            gname="-srgb";;
+         --linear)
+            gname="-lin";;
+         --1.8)
+            gname="-18";;
+         *)
+            gname="-$gamma";;
+      esac
+      "$mp" $gamma "$1" "$2" "test-$1-$2$gname.png"
+   done
+}
+#
+for ct in gray palette
+do
+   for bd in 1 2 4 8
+   do
+      doit "$ct" "$bd"
+   done
+done
+#
+doit "gray" "16"
+#
+for ct in gray-alpha rgb rgb-alpha
+do
+   for bd in 8 16
+   do
+      doit "$ct" "$bd"
+   done
+done

contrib/libtests/pngunknown.c

@@ -0,0 +1,960 @@
+
+/* pngunknown.c - test the read side unknown chunk handling
+ *
+ * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Copyright (c) 2012 Glenn Randers-Pehrson
+ * Written by John Cunningham Bowler
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * NOTES:
+ *   This is a C program that is intended to be linked against libpng.  It
+ *   allows the libpng unknown handling code to be tested by interpreting
+ *   arguments to save or discard combinations of chunks.  The program is
+ *   currently just a minimal validation for the built-in libpng facilities.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <setjmp.h>
+
+/* Define the following to use this test against your installed libpng, rather
+ * than the one being built here:
+ */
+#ifdef PNG_FREESTANDING_TESTS
+#  include <png.h>
+#else
+#  include "../../png.h"
+#endif
+
+#ifdef PNG_READ_SUPPORTED
+
+#if PNG_LIBPNG_VER < 10500
+/* This deliberately lacks the PNG_CONST. */
+typedef png_byte *png_const_bytep;
+
+/* This is copied from 1.5.1 png.h: */
+#define PNG_INTERLACE_ADAM7_PASSES 7
+#define PNG_PASS_START_ROW(pass) (((1U&~(pass))<<(3-((pass)>>1)))&7)
+#define PNG_PASS_START_COL(pass) (((1U& (pass))<<(3-(((pass)+1)>>1)))&7)
+#define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)
+#define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)
+#define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\
+   -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))
+#define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\
+   -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))
+#define PNG_ROW_FROM_PASS_ROW(yIn, pass) \
+   (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))
+#define PNG_COL_FROM_PASS_COL(xIn, pass) \
+   (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))
+#define PNG_PASS_MASK(pass,off) ( \
+   ((0x110145AFU>>(((7-(off))-(pass))<<2)) & 0xFU) | \
+   ((0x01145AF0U>>(((7-(off))-(pass))<<2)) & 0xF0U))
+#define PNG_ROW_IN_INTERLACE_PASS(y, pass) \
+   ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)
+#define PNG_COL_IN_INTERLACE_PASS(x, pass) \
+   ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)
+
+/* These are needed too for the default build: */
+#define PNG_WRITE_16BIT_SUPPORTED
+#define PNG_READ_16BIT_SUPPORTED
+
+/* This comes from pnglibconf.h afer 1.5: */
+#define PNG_FP_1 100000
+#define PNG_GAMMA_THRESHOLD_FIXED\
+   ((png_fixed_point)(PNG_GAMMA_THRESHOLD * PNG_FP_1))
+#endif
+
+#if PNG_LIBPNG_VER < 10600
+   /* 1.6.0 constifies many APIs. The following exists to allow pngvalid to be
+    * compiled against earlier versions.
+    */
+#  define png_const_structp png_structp
+#endif
+
+
+/* Copied from pngpriv.h */
+#define PNG_32b(b,s) ((png_uint_32)(b) << (s))
+#define PNG_CHUNK(b1,b2,b3,b4) \
+   (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
+
+#define png_IHDR PNG_CHUNK( 73,  72,  68,  82)
+#define png_IDAT PNG_CHUNK( 73,  68,  65,  84)
+#define png_IEND PNG_CHUNK( 73,  69,  78,  68)
+#define png_PLTE PNG_CHUNK( 80,  76,  84,  69)
+#define png_bKGD PNG_CHUNK( 98,  75,  71,  68)
+#define png_cHRM PNG_CHUNK( 99,  72,  82,  77)
+#define png_gAMA PNG_CHUNK(103,  65,  77,  65)
+#define png_hIST PNG_CHUNK(104,  73,  83,  84)
+#define png_iCCP PNG_CHUNK(105,  67,  67,  80)
+#define png_iTXt PNG_CHUNK(105,  84,  88, 116)
+#define png_oFFs PNG_CHUNK(111,  70,  70, 115)
+#define png_pCAL PNG_CHUNK(112,  67,  65,  76)
+#define png_sCAL PNG_CHUNK(115,  67,  65,  76)
+#define png_pHYs PNG_CHUNK(112,  72,  89, 115)
+#define png_sBIT PNG_CHUNK(115,  66,  73,  84)
+#define png_sPLT PNG_CHUNK(115,  80,  76,  84)
+#define png_sRGB PNG_CHUNK(115,  82,  71,  66)
+#define png_sTER PNG_CHUNK(115,  84,  69,  82)
+#define png_tEXt PNG_CHUNK(116,  69,  88, 116)
+#define png_tIME PNG_CHUNK(116,  73,  77,  69)
+#define png_tRNS PNG_CHUNK(116,  82,  78,  83)
+#define png_zTXt PNG_CHUNK(122,  84,  88, 116)
+#define png_vpAg PNG_CHUNK('v', 'p', 'A', 'g')
+
+/* Test on flag values as defined in the spec (section 5.4): */
+#define PNG_CHUNK_ANCILLARY(c )   (1 & ((c) >> 29))
+#define PNG_CHUNK_CRITICAL(c)     (!PNG_CHUNK_ANCILLARY(c))
+#define PNG_CHUNK_PRIVATE(c)      (1 & ((c) >> 21))
+#define PNG_CHUNK_RESERVED(c)     (1 & ((c) >> 13))
+#define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >>  5))
+
+/* Chunk information */
+#define PNG_INFO_tEXt 0x10000000U
+#define PNG_INFO_iTXt 0x20000000U
+#define PNG_INFO_zTXt 0x40000000U
+
+#define PNG_INFO_sTER 0x01000000U
+#define PNG_INFO_vpAg 0x02000000U
+
+#define ABSENT  0
+#define START   1
+#define END     2
+
+static struct
+{
+   char        name[5];
+   png_uint_32 flag;
+   png_uint_32 tag;
+   int         unknown;    /* Chunk not known to libpng */
+   int         all;        /* Chunk set by the '-1' option */
+   int         position;   /* position in pngtest.png */
+   int         keep;       /* unknown handling setting */
+} chunk_info[] = {
+   /* Critical chunks */
+   { "IDAT", PNG_INFO_IDAT, png_IDAT, 0, 0,  START, 0 }, /* must be [0] */
+   { "PLTE", PNG_INFO_PLTE, png_PLTE, 0, 0, ABSENT, 0 },
+
+   /* Non-critical chunks that libpng handles */
+   { "bKGD", PNG_INFO_bKGD, png_bKGD, 0, 1,  START, 0 },
+   { "cHRM", PNG_INFO_cHRM, png_cHRM, 0, 1,  START, 0 },
+   { "gAMA", PNG_INFO_gAMA, png_gAMA, 0, 1,  START, 0 },
+   { "hIST", PNG_INFO_hIST, png_hIST, 0, 1, ABSENT, 0 },
+   { "iCCP", PNG_INFO_iCCP, png_iCCP, 0, 1, ABSENT, 0 },
+   { "iTXt", PNG_INFO_iTXt, png_iTXt, 0, 1, ABSENT, 0 },
+   { "oFFs", PNG_INFO_oFFs, png_oFFs, 0, 1,  START, 0 },
+   { "pCAL", PNG_INFO_pCAL, png_pCAL, 0, 1,  START, 0 },
+   { "pHYs", PNG_INFO_pHYs, png_pHYs, 0, 1,  START, 0 },
+   { "sBIT", PNG_INFO_sBIT, png_sBIT, 0, 1,  START, 0 },
+   { "sCAL", PNG_INFO_sCAL, png_sCAL, 0, 1,  START, 0 },
+   { "sPLT", PNG_INFO_sPLT, png_sPLT, 0, 1, ABSENT, 0 },
+   { "sRGB", PNG_INFO_sRGB, png_sRGB, 0, 1,  START, 0 },
+   { "tEXt", PNG_INFO_tEXt, png_tEXt, 0, 1,  START, 0 },
+   { "tIME", PNG_INFO_tIME, png_tIME, 0, 1,  START, 0 },
+   { "tRNS", PNG_INFO_tRNS, png_tRNS, 0, 0, ABSENT, 0 },
+   { "zTXt", PNG_INFO_zTXt, png_zTXt, 0, 1,    END, 0 },
+
+   /* No libpng handling */
+   { "sTER", PNG_INFO_sTER, png_sTER, 1, 1,  START, 0 },
+   { "vpAg", PNG_INFO_vpAg, png_vpAg, 1, 0,  START, 0 },
+};
+
+#define NINFO ((int)((sizeof chunk_info)/(sizeof chunk_info[0])))
+
+static void
+clear_keep(void)
+{
+   int i = NINFO;
+   while (--i >= 0)
+      chunk_info[i].keep = 0;
+}
+
+static int
+find(const char *name)
+{
+   int i = NINFO;
+   while (--i >= 0)
+   {
+      if (memcmp(chunk_info[i].name, name, 4) == 0)
+         break;
+   }
+
+   return i;
+}
+
+static int
+findb(const png_byte *name)
+{
+   int i = NINFO;
+   while (--i >= 0)
+   {
+      if (memcmp(chunk_info[i].name, name, 4) == 0)
+         break;
+   }
+
+   return i;
+}
+
+static int
+find_by_flag(png_uint_32 flag)
+{
+   int i = NINFO;
+
+   while (--i >= 0) if (chunk_info[i].flag == flag) return i;
+
+   fprintf(stderr, "pngunknown: internal error\n");
+   exit(4);
+}
+
+static int
+ancillary(const char *name)
+{
+   return PNG_CHUNK_ANCILLARY(PNG_CHUNK(name[0], name[1], name[2], name[3]));
+}
+
+static int
+ancillaryb(const png_byte *name)
+{
+   return PNG_CHUNK_ANCILLARY(PNG_CHUNK(name[0], name[1], name[2], name[3]));
+}
+
+/* Type of an error_ptr */
+typedef struct
+{
+   jmp_buf     error_return;
+   png_structp png_ptr;
+   png_infop   info_ptr, end_ptr;
+   int         error_count;
+   int         warning_count;
+   const char *program;
+   const char *file;
+   const char *test;
+} display;
+
+static const char init[] = "initialization";
+static const char cmd[] = "command line";
+
+static void
+init_display(display *d, const char *program)
+{
+   memset(d, 0, sizeof *d);
+   d->png_ptr = NULL;
+   d->info_ptr = d->end_ptr = NULL;
+   d->error_count = d->warning_count = 0;
+   d->program = program;
+   d->file = program;
+   d->test = init;
+}
+
+static void
+clean_display(display *d)
+{
+   png_destroy_read_struct(&d->png_ptr, &d->info_ptr, &d->end_ptr);
+
+   /* This must not happen - it might cause an app crash */
+   if (d->png_ptr != NULL || d->info_ptr != NULL || d->end_ptr != NULL)
+   {
+      fprintf(stderr, "%s(%s): png_destroy_read_struct error\n", d->file,
+         d->test);
+      exit(1);
+   }
+
+   /* Invalidate the test */
+   d->test = init;
+}
+
+PNG_FUNCTION(void, display_exit, (display *d), static PNG_NORETURN)
+{
+   ++(d->error_count);
+
+   if (d->png_ptr != NULL)
+      clean_display(d);
+
+   /* During initialization and if this is a single command line argument set
+    * exit now - there is only one test, otherwise longjmp to do the next test.
+    */
+   if (d->test == init || d->test == cmd)
+      exit(1);
+
+   longjmp(d->error_return, 1);
+}
+
+static int
+display_rc(const display *d, int strict)
+{
+   return d->error_count + (strict ? d->warning_count : 0);
+}
+
+/* libpng error and warning callbacks */
+PNG_FUNCTION(void, error, (png_structp png_ptr, const char *message),
+   static PNG_NORETURN)
+{
+   display *d = (display*)png_get_error_ptr(png_ptr);
+
+   fprintf(stderr, "%s(%s): libpng error: %s\n", d->file, d->test, message);
+   display_exit(d);
+}
+
+static void
+warning(png_structp png_ptr, const char *message)
+{
+   display *d = (display*)png_get_error_ptr(png_ptr);
+
+   fprintf(stderr, "%s(%s): libpng warning: %s\n", d->file, d->test, message);
+   ++(d->warning_count);
+}
+
+static png_uint_32
+get_valid(display *d, png_infop info_ptr)
+{
+   png_uint_32 flags = png_get_valid(d->png_ptr, info_ptr, (png_uint_32)~0);
+
+   /* Map the text chunks back into the flags */
+   {
+      png_textp text;
+      png_uint_32 ntext = png_get_text(d->png_ptr, info_ptr, &text, NULL);
+
+      while (ntext-- > 0) switch (text[ntext].compression)
+      {
+         case -1:
+            flags |= PNG_INFO_tEXt;
+            break;
+         case 0:
+            flags |= PNG_INFO_zTXt;
+            break;
+         case 1:
+         case 2:
+            flags |= PNG_INFO_iTXt;
+            break;
+         default:
+            fprintf(stderr, "%s(%s): unknown text compression %d\n", d->file,
+               d->test, text[ntext].compression);
+            display_exit(d);
+      }
+   }
+
+   return flags;
+}
+
+static png_uint_32
+get_unknown(display *d, int def, png_infop info_ptr)
+{
+   /* Create corresponding 'unknown' flags */
+   png_uint_32 flags = 0;
+   {
+      png_unknown_chunkp unknown;
+      int num_unknown = png_get_unknown_chunks(d->png_ptr, info_ptr, &unknown);
+
+      while (--num_unknown >= 0)
+      {
+         int chunk = findb(unknown[num_unknown].name);
+
+         /* Chunks not known to pngunknown must be validated here; since they
+          * must also be unknown to libpng the 'def' behavior should have been
+          * used.
+          */
+         if (chunk < 0) switch (def)
+         {
+            default: /* impossible */
+            case PNG_HANDLE_CHUNK_AS_DEFAULT:
+            case PNG_HANDLE_CHUNK_NEVER:
+               fprintf(stderr, "%s(%s): %s: %s: unknown chunk saved\n",
+                  d->file, d->test, def ? "discard" : "default",
+                  unknown[num_unknown].name);
+               ++(d->error_count);
+               break;
+
+            case PNG_HANDLE_CHUNK_IF_SAFE:
+               if (!ancillaryb(unknown[num_unknown].name))
+               {
+                  fprintf(stderr,
+                     "%s(%s): if-safe: %s: unknown critical chunk saved\n",
+                     d->file, d->test, unknown[num_unknown].name);
+                  ++(d->error_count);
+                  break;
+               }
+               /* FALL THROUGH (safe) */
+            case PNG_HANDLE_CHUNK_ALWAYS:
+               break;
+         }
+
+         else
+            flags |= chunk_info[chunk].flag;
+      }
+   }
+
+   return flags;
+}
+
+static int
+check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
+   display *d)
+{
+   int i, def = PNG_HANDLE_CHUNK_AS_DEFAULT, npasses, ipass;
+   png_uint_32 height;
+
+   /* Some of these errors are permanently fatal and cause an exit here, others
+    * are per-test and cause an error return.
+    */
+   d->png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, d, error,
+      warning);
+   if (d->png_ptr == NULL)
+   {
+      fprintf(stderr, "%s(%s): could not allocate png struct\n", d->file,
+         d->test);
+      /* Terminate here, this error is not test specific. */
+      exit(1);
+   }
+
+   d->info_ptr = png_create_info_struct(d->png_ptr);
+   d->end_ptr = png_create_info_struct(d->png_ptr);
+   if (d->info_ptr == NULL || d->end_ptr == NULL)
+   {
+      fprintf(stderr, "%s(%s): could not allocate png info\n", d->file,
+         d->test);
+      clean_display(d);
+      exit(1);
+   }
+
+   png_init_io(d->png_ptr, fp);
+
+   /* Handle each argument in turn; multiple settings are possible for the same
+    * chunk and multiple calls will occur (the last one should override all
+    * preceding ones).
+    */
+   for (i=0; i<argc; ++i)
+   {
+      const char *equals = strchr(argv[i], '=');
+
+      if (equals != NULL)
+      {
+         int chunk, option;
+
+         if (strcmp(equals+1, "default") == 0)
+            option = PNG_HANDLE_CHUNK_AS_DEFAULT;
+         else if (strcmp(equals+1, "discard") == 0)
+            option = PNG_HANDLE_CHUNK_NEVER;
+         else if (strcmp(equals+1, "if-safe") == 0)
+            option = PNG_HANDLE_CHUNK_IF_SAFE;
+         else if (strcmp(equals+1, "save") == 0)
+            option = PNG_HANDLE_CHUNK_ALWAYS;
+         else
+         {
+            fprintf(stderr, "%s(%s): %s: unrecognized chunk option\n", d->file,
+               d->test, argv[i]);
+            display_exit(d);
+         }
+
+         switch (equals - argv[i])
+         {
+            case 4: /* chunk name */
+               chunk = find(argv[i]);
+
+               if (chunk >= 0)
+               {
+                  /* These #if tests have the effect of skipping the arguments
+                   * if SAVE support is unavailable - we can't do a useful test
+                   * in this case, so we just check the arguments!  This could
+                   * be improved in the future by using the read callback.
+                   */
+#                 ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+                     png_byte name[5];
+
+                     memcpy(name, chunk_info[chunk].name, 5);
+                     png_set_keep_unknown_chunks(d->png_ptr, option, name, 1);
+                     chunk_info[chunk].keep = option;
+#                 endif
+                  continue;
+               }
+
+               break;
+
+            case 7: /* default */
+               if (memcmp(argv[i], "default", 7) == 0)
+               {
+#                 ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+                     png_set_keep_unknown_chunks(d->png_ptr, option, NULL, 0);
+#                 endif
+                  def = option;
+                  continue;
+               }
+
+               break;
+
+            case 3: /* all */
+               if (memcmp(argv[i], "all", 3) == 0)
+               {
+#                 ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+                     png_set_keep_unknown_chunks(d->png_ptr, option, NULL, -1);
+                     def = option;
+
+                     for (chunk = 0; chunk < NINFO; ++chunk)
+                        if (chunk_info[chunk].all)
+                           chunk_info[chunk].keep = option;
+#                 endif
+                  continue;
+               }
+
+               break;
+
+            default: /* some misplaced = */
+
+               break;
+         }
+      }
+
+      fprintf(stderr, "%s(%s): %s: unrecognized chunk argument\n", d->file,
+         d->test, argv[i]);
+      display_exit(d);
+   }
+
+   png_read_info(d->png_ptr, d->info_ptr);
+
+   switch (png_get_interlace_type(d->png_ptr, d->info_ptr))
+   {
+      case PNG_INTERLACE_NONE:
+         npasses = 1;
+         break;
+
+      case PNG_INTERLACE_ADAM7:
+         npasses = PNG_INTERLACE_ADAM7_PASSES;
+         break;
+
+      default:
+         /* Hard error because it is not test specific */
+         fprintf(stderr, "%s(%s): invalid interlace type\n", d->file, d->test);
+         clean_display(d);
+         exit(1);
+   }
+
+   /* Skip the image data, if IDAT is not being handled then don't do this
+    * because it will cause a CRC error.
+    */
+   if (chunk_info[0/*IDAT*/].keep == PNG_HANDLE_CHUNK_AS_DEFAULT)
+   {
+      png_start_read_image(d->png_ptr);
+      height = png_get_image_height(d->png_ptr, d->info_ptr);
+
+      if (npasses > 1)
+      {
+         png_uint_32 width = png_get_image_width(d->png_ptr, d->info_ptr);
+
+         for (ipass=0; ipass<npasses; ++ipass)
+         {
+            png_uint_32 wPass = PNG_PASS_COLS(width, ipass);
+
+            if (wPass > 0)
+            {
+               png_uint_32 y;
+
+               for (y=0; y<height; ++y) if (PNG_ROW_IN_INTERLACE_PASS(y, ipass))
+                  png_read_row(d->png_ptr, NULL, NULL);
+            }
+         }
+      } /* interlaced */
+
+      else /* not interlaced */
+      {
+         png_uint_32 y;
+
+         for (y=0; y<height; ++y)
+            png_read_row(d->png_ptr, NULL, NULL);
+      }
+   }
+
+   png_read_end(d->png_ptr, d->end_ptr);
+
+   flags[0] = get_valid(d, d->info_ptr);
+   flags[1] = get_unknown(d, def, d->info_ptr);
+
+   /* Only png_read_png sets PNG_INFO_IDAT! */
+   flags[chunk_info[0/*IDAT*/].keep != PNG_HANDLE_CHUNK_AS_DEFAULT] |=
+      PNG_INFO_IDAT;
+
+   flags[2] = get_valid(d, d->end_ptr);
+   flags[3] = get_unknown(d, def, d->end_ptr);
+
+   clean_display(d);
+
+   return def;
+}
+
+static void
+check_error(display *d, png_uint_32 flags, const char *message)
+{
+   while (flags)
+   {
+      png_uint_32 flag = flags & -(png_int_32)flags;
+      int i = find_by_flag(flag);
+
+      fprintf(stderr, "%s(%s): chunk %s: %s\n", d->file, d->test,
+         chunk_info[i].name, message);
+      ++(d->error_count);
+
+      flags &= ~flag;
+   }
+}
+
+static void
+check_handling(display *d, int def, png_uint_32 chunks, png_uint_32 known,
+   png_uint_32 unknown, const char *position)
+{
+   while (chunks)
+   {
+      png_uint_32 flag = chunks & -(png_int_32)chunks;
+      int i = find_by_flag(flag);
+      int keep = chunk_info[i].keep;
+      const char *type;
+      const char *errorx = NULL;
+
+      if (chunk_info[i].unknown)
+      {
+         if (keep == PNG_HANDLE_CHUNK_AS_DEFAULT)
+         {
+            type = "UNKNOWN (default)";
+            keep = def;
+         }
+
+         else
+            type = "UNKNOWN (specified)";
+
+         if (flag & known)
+            errorx = "chunk processed";
+
+         else switch (keep)
+         {
+            case PNG_HANDLE_CHUNK_AS_DEFAULT:
+               if (flag & unknown)
+                  errorx = "DEFAULT: unknown chunk saved";
+               break;
+
+            case PNG_HANDLE_CHUNK_NEVER:
+               if (flag & unknown)
+                  errorx = "DISCARD: unknown chunk saved";
+               break;
+
+            case PNG_HANDLE_CHUNK_IF_SAFE:
+               if (ancillary(chunk_info[i].name))
+               {
+                  if (!(flag & unknown))
+                     errorx = "IF-SAFE: unknown ancillary chunk lost";
+               }
+
+               else if (flag & unknown)
+                  errorx = "IF-SAFE: unknown critical chunk saved";
+               break;
+
+            case PNG_HANDLE_CHUNK_ALWAYS:
+               if (!(flag & unknown))
+                  errorx = "SAVE: unknown chunk lost";
+               break;
+
+            default:
+               errorx = "internal error: bad keep";
+               break;
+         }
+      } /* unknown chunk */
+
+      else /* known chunk */
+      {
+         type = "KNOWN";
+
+         if (flag & known)
+         {
+            /* chunk was processed, it won't have been saved because that is
+             * caught below when checking for inconsistent processing.
+             */
+            if (keep != PNG_HANDLE_CHUNK_AS_DEFAULT)
+               errorx = "!DEFAULT: known chunk processed";
+         }
+
+         else /* not processed */ switch (keep)
+         {
+            case PNG_HANDLE_CHUNK_AS_DEFAULT:
+               errorx = "DEFAULT: known chunk not processed";
+               break;
+
+            case PNG_HANDLE_CHUNK_NEVER:
+               if (flag & unknown)
+                  errorx = "DISCARD: known chunk saved";
+               break;
+
+            case PNG_HANDLE_CHUNK_IF_SAFE:
+               if (ancillary(chunk_info[i].name))
+               {
+                  if (!(flag & unknown))
+                     errorx = "IF-SAFE: known ancillary chunk lost";
+               }
+
+               else if (flag & unknown)
+                  errorx = "IF-SAFE: known critical chunk saved";
+               break;
+
+            case PNG_HANDLE_CHUNK_ALWAYS:
+               if (!(flag & unknown))
+                  errorx = "SAVE: known chunk lost";
+               break;
+
+            default:
+               errorx = "internal error: bad keep (2)";
+               break;
+         }
+      }
+
+      if (errorx != NULL)
+      {
+         ++(d->error_count);
+         fprintf(stderr, "%s(%s): %s %s %s: %s\n",
+            d->file, d->test, type, chunk_info[i].name, position, errorx);
+      }
+
+      chunks &= ~flag;
+   }
+}
+
+static void
+perform_one_test(FILE *fp, int argc, const char **argv,
+   png_uint_32 *default_flags, display *d)
+{
+   int def;
+   png_uint_32 flags[2][4];
+
+   rewind(fp);
+   clear_keep();
+   memcpy(flags[0], default_flags, sizeof flags[0]);
+
+   def = check(fp, argc, argv, flags[1], d);
+
+   /* Chunks should either be known or unknown, never both and this should apply
+    * whether the chunk is before or after the IDAT (actually, the app can
+    * probably change this by swapping the handling after the image, but this
+    * test does not do that.)
+    */
+   check_error(d, (flags[0][0]|flags[0][2]) & (flags[0][1]|flags[0][3]),
+      "chunk handled inconsistently in count tests");
+   check_error(d, (flags[1][0]|flags[1][2]) & (flags[1][1]|flags[1][3]),
+      "chunk handled inconsistently in option tests");
+
+   /* Now find out what happened to each chunk before and after the IDAT and
+    * determine if the behavior was correct.  First some basic sanity checks,
+    * any known chunk should be known in the original count, any unknown chunk
+    * should be either known or unknown in the original.
+    */
+   {
+      png_uint_32 test;
+
+      test = flags[1][0] & ~flags[0][0];
+      check_error(d, test, "new known chunk before IDAT");
+      test = flags[1][1] & ~(flags[0][0] | flags[0][1]);
+      check_error(d, test, "new unknown chunk before IDAT");
+      test = flags[1][2] & ~flags[0][2];
+      check_error(d, test, "new known chunk after IDAT");
+      test = flags[1][3] & ~(flags[0][2] | flags[0][3]);
+      check_error(d, test, "new unknown chunk after IDAT");
+   }
+
+   /* Now each chunk in the original list should have been handled according to
+    * the options set for that chunk, regardless of whether libpng knows about
+    * it or not.
+    */
+   check_handling(d, def, flags[0][0] | flags[0][1], flags[1][0], flags[1][1],
+      "before IDAT");
+   check_handling(d, def, flags[0][2] | flags[0][3], flags[1][2], flags[1][3],
+      "after IDAT");
+}
+
+static void
+perform_one_test_safe(FILE *fp, int argc, const char **argv,
+   png_uint_32 *default_flags, display *d, const char *test)
+{
+   if (setjmp(d->error_return) == 0)
+   {
+      d->test = test; /* allow use of d->error_return */
+      perform_one_test(fp, argc, argv, default_flags, d);
+      d->test = init; /* prevent use of d->error_return */
+   }
+}
+
+static const char *standard_tests[] =
+{
+ "discard", "default=discard", 0,
+ "save", "default=save", 0,
+ "if-safe", "default=if-safe", 0,
+ "vpAg", "vpAg=if-safe", 0,
+ "sTER", "sTER=if-safe", 0,
+ "IDAT", "default=discard", "IDAT=save", 0,
+ "sAPI", "bKGD=save", "cHRM=save", "gAMA=save", "all=discard", "iCCP=save",
+   "sBIT=save", "sRGB=save", 0,
+ 0/*end*/
+};
+
+static PNG_NORETURN void
+usage(const char *program, const char *reason)
+{
+   fprintf(stderr, "pngunknown: %s: usage:\n %s [--strict] "
+      "--default|{(CHNK|default|all)=(default|discard|if-safe|save)} "
+      "testfile.png\n", reason, program);
+   exit(2);
+}
+
+int
+main(int argc, const char **argv)
+{
+   FILE *fp;
+   png_uint_32 default_flags[4/*valid,unknown{before,after}*/];
+   int strict = 0, default_tests = 0;
+   const char *count_argv = "default=save";
+   const char *touch_file = NULL;
+   display d;
+
+   init_display(&d, argv[0]);
+
+   while (++argv, --argc > 0)
+   {
+      if (strcmp(*argv, "--strict") == 0)
+         strict = 1;
+
+      else if (strcmp(*argv, "--default") == 0)
+         default_tests = 1;
+
+      else if (strcmp(*argv, "--touch") == 0)
+      {
+         if (argc > 1)
+            touch_file = *++argv, --argc;
+
+         else
+            usage(d.program, "--touch: missing file name");
+      }
+
+      else
+         break;
+   }
+
+   /* A file name is required, but there should be no other arguments if
+    * --default was specified.
+    */
+   if (argc <= 0)
+      usage(d.program, "missing test file");
+
+   /* GCC BUG: if (default_tests && argc != 1) triggers some weird GCC argc
+    * optimization which causes warnings with -Wstrict-overflow!
+    */
+   else if (default_tests) if (argc != 1)
+      usage(d.program, "extra arguments");
+
+#  ifndef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+      fprintf(stderr, "%s: warning: no 'save' support so arguments ignored\n",
+         d.program);
+#  endif
+
+   /* The name of the test file is the last argument; remove it. */
+   d.file = argv[--argc];
+
+   fp = fopen(d.file, "rb");
+   if (fp == NULL)
+   {
+      perror(d.file);
+      exit(2);
+   }
+
+   /* First find all the chunks, known and unknown, in the test file, a failure
+    * here aborts the whole test.
+    */
+   if (check(fp, 1, &count_argv, default_flags, &d) !=
+      PNG_HANDLE_CHUNK_ALWAYS)
+   {
+      fprintf(stderr, "%s: %s: internal error\n", d.program, d.file);
+      exit(3);
+   }
+
+   /* Now find what the various supplied options cause to change: */
+   if (!default_tests)
+   {
+      d.test = cmd; /* acts as a flag to say exit, do not longjmp */
+      perform_one_test(fp, argc, argv, default_flags, &d);
+      d.test = init;
+   }
+
+   else
+   {
+      const char **test = standard_tests;
+
+      /* Set the exit_test pointer here so we can continue after a libpng error.
+       * NOTE: this leaks memory because the png_struct data from the failing
+       * test is never freed.
+       */
+      while (*test)
+      {
+         const char *this_test = *test++;
+         const char **next = test;
+         int count = display_rc(&d, strict), new_count;
+         const char *result;
+         int arg_count = 0;
+
+         while (*next) ++next, ++arg_count;
+
+         perform_one_test_safe(fp, arg_count, test, default_flags, &d,
+            this_test);
+
+         new_count = display_rc(&d, strict);
+
+         if (new_count == count)
+            result = "PASS";
+
+         else
+            result = "FAIL";
+
+         printf("%s: %s %s\n", result, d.program, this_test);
+
+         test = next+1;
+      }
+   }
+
+   fclose(fp);
+
+   if (display_rc(&d, strict) == 0)
+   {
+      /* Success, touch the success file if appropriate */
+      if (touch_file != NULL)
+      {
+         FILE *fsuccess = fopen(touch_file, "wt");
+
+         if (fsuccess != NULL)
+         {
+            int err = 0;
+            fprintf(fsuccess, "PNG unknown tests succeeded\n");
+            fflush(fsuccess);
+            err = ferror(fsuccess);
+
+            if (fclose(fsuccess) || err)
+            {
+               fprintf(stderr, "%s: write failed\n", touch_file);
+               exit(1);
+            }
+         }
+
+         else
+         {
+            fprintf(stderr, "%s: open failed\n", touch_file);
+            exit(1);
+         }
+      }
+
+      return 0;
+   }
+
+   return 1;
+}
+
+#else
+int
+main(void)
+{
+   fprintf(stderr,
+   " test ignored because libpng was not built with unknown chunk support\n");
+   return 0;
+}
+#endif

contrib/libtests/readpng.c

@@ -0,0 +1,104 @@
+/* readpng.c
+ *
+ * Copyright (c) 2013 John Cunningham Bowler
+ *
+ * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Load an arbitrary number of PNG files (from the command line, or, if there
+ * are no arguments on the command line, from stdin) then run a time test by
+ * reading each file by row.  The test does nothing with the read result and
+ * does no transforms.  The only output is a time as a floating point number of
+ * seconds with 9 decimal digits.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#if (defined HAVE_CONFIG_H) && !(defined PNG_NO_CONFIG_H)
+#  include <config.h>
+#endif
+
+/* Define the following to use this test against your installed libpng, rather
+ * than the one being built here:
+ */
+#ifdef PNG_FREESTANDING_TESTS
+#  include <png.h>
+#else
+#  include "../../png.h"
+#endif
+
+static int
+read_png(FILE *fp)
+{
+   png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);
+   png_infop info_ptr = NULL;
+   png_bytep row = NULL, display = NULL;
+
+   if (png_ptr == NULL)
+      return 0;
+
+   if (setjmp(png_jmpbuf(png_ptr)))
+   {
+      png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+      if (row != NULL) free(row);
+      if (display != NULL) free(display);
+      return 0;
+   }
+
+   png_init_io(png_ptr, fp);
+
+   info_ptr = png_create_info_struct(png_ptr);
+   if (info_ptr == NULL)
+      png_error(png_ptr, "OOM allocating info structure");
+
+   png_set_keep_unknown_chunks(png_ptr, PNG_HANDLE_CHUNK_ALWAYS, NULL, 0);
+
+   png_read_info(png_ptr, info_ptr);
+
+   {
+      png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+
+      row = malloc(rowbytes);
+      display = malloc(rowbytes);
+
+      if (row == NULL || display == NULL)
+         png_error(png_ptr, "OOM allocating row buffers");
+
+      {
+         png_uint_32 height = png_get_image_height(png_ptr, info_ptr);
+         int passes = png_set_interlace_handling(png_ptr);
+         int pass;
+
+         png_start_read_image(png_ptr);
+
+         for (pass = 0; pass < passes; ++pass)
+         {
+            png_uint_32 y = height;
+
+            /* NOTE: this trashes the row each time; interlace handling won't
+             * work, but this avoids memory thrashing for speed testing.
+             */
+            while (y-- > 0)
+               png_read_row(png_ptr, row, display);
+         }
+      }
+   }
+
+   /* Make sure to read to the end of the file: */
+   png_read_end(png_ptr, info_ptr);
+   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+   free(row);
+   free(display);
+   return 1;
+}
+
+int
+main(void)
+{
+   /* Exit code 0 on success. */
+   return !read_png(stdin);
+}

contrib/libtests/tarith.c

@@ -0,0 +1,999 @@
+
+/* tarith.c
+ *
+ * Copyright (c) 2011,2012 John Cunningham Bowler
+ *
+ * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Test internal arithmetic functions of libpng.
+ *
+ * This code must be linked against a math library (-lm), but does not require
+ * libpng or zlib to work.  Because it includes the complete source of 'png.c'
+ * it tests the code with whatever compiler options are used to build it.
+ * Changing these options can substantially change the errors in the
+ * calculations that the compiler chooses!
+ */
+#define _POSIX_SOURCE 1
+#define _ISOC99_SOURCE 1
+
+/* Obtain a copy of the code to be tested (plus other things), disabling
+ * stuff that is not required.
+ */
+#include <math.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <string.h>
+#include <assert.h>
+
+#include "../../pngpriv.h"
+
+#define png_error png_warning
+
+void png_warning(png_const_structrp png_ptr, png_const_charp msg)
+{
+   fprintf(stderr, "validation: %s\n", msg);
+}
+
+#define png_fixed_error png_fixed_warning
+
+void png_fixed_warning(png_const_structrp png_ptr, png_const_charp msg)
+{
+   fprintf(stderr, "overflow in: %s\n", msg);
+}
+
+#define png_set_error_fn(pp, ep, efp, wfp) ((void)0)
+#define png_malloc(pp, s) malloc(s)
+#define png_malloc_warn(pp, s) malloc(s)
+#define png_malloc_base(pp, s) malloc(s)
+#define png_calloc(pp, s) calloc(1, (s))
+#define png_free(pp, s) free(s)
+
+#define png_safecat(b, sb, pos, str) (pos)
+#define png_format_number(start, end, format, number) (start)
+
+#define crc32(crc, pp, s) (crc)
+#define inflateReset(zs) Z_OK
+
+#define png_create_struct(type) (0)
+#define png_destroy_struct(pp) ((void)0)
+#define png_create_struct_2(type, m, mm) (0)
+#define png_destroy_struct_2(pp, f, mm) ((void)0)
+
+#undef PNG_SIMPLIFIED_READ_SUPPORTED
+#undef PNG_SIMPLIFIED_WRITE_SUPPORTED
+#undef PNG_USER_MEM_SUPPORTED
+
+#include "../../png.c"
+
+/* Validate ASCII to fp routines. */
+static int verbose = 0;
+
+int validation_ascii_to_fp(int count, int argc, char **argv)
+{
+   int    showall = 0;
+   double max_error=2;      /* As a percentage error-in-last-digit/.5 */
+   double max_error_abs=17; /* Used when precision is DBL_DIG */
+   double max = 0;
+   double max_abs = 0;
+   double test = 0; /* Important to test this. */
+   int    precision = 5;
+   int    nonfinite = 0;
+   int    finite = 0;
+   int    ok = 0;
+   int    failcount = 0;
+   int    minorarith = 0;
+
+   while (--argc > 0)
+      if (strcmp(*++argv, "-a") == 0)
+         showall = 1;
+      else if (strcmp(*argv, "-e") == 0 && argc > 0)
+      {
+         --argc;
+         max_error = atof(*++argv);
+      }
+      else if (strcmp(*argv, "-E") == 0 && argc > 0)
+      {
+         --argc;
+         max_error_abs = atof(*++argv);
+      }
+      else
+      {
+         fprintf(stderr, "unknown argument %s\n", *argv);
+         return 1;
+      }
+
+   do
+   {
+      png_size_t index;
+      int state, failed = 0;
+      char buffer[64];
+
+      if (isfinite(test))
+         ++finite;
+      else
+         ++nonfinite;
+
+      if (verbose)
+         fprintf(stderr, "%.*g %d\n", DBL_DIG, test, precision);
+
+      /* Check for overflow in the buffer by setting a marker. */
+      memset(buffer, 71, sizeof buffer);
+
+      png_ascii_from_fp(0, buffer, precision+10, test, precision);
+
+      /* Allow for a three digit exponent, this stuff will fail if
+       * the exponent is bigger than this!
+       */
+      if (buffer[precision+7] != 71)
+      {
+         fprintf(stderr, "%g[%d] -> '%s'[%lu] buffer overflow\n", test,
+            precision, buffer, (unsigned long)strlen(buffer));
+         failed = 1;
+      }
+
+      /* Following are used for the number parser below and must be
+       * initialized to zero.
+       */
+      state = 0;
+      index = 0;
+      if (!isfinite(test))
+      {
+         /* Expect 'inf' */
+         if (test >= 0 && strcmp(buffer, "inf") ||
+             test <  0 && strcmp(buffer, "-inf"))
+         {
+            fprintf(stderr, "%g[%d] -> '%s' but expected 'inf'\n", test,
+               precision, buffer);
+            failed = 1;
+         }
+      }
+      else if (!png_check_fp_number(buffer, precision+10, &state, &index) ||
+          buffer[index] != 0)
+      {
+         fprintf(stderr, "%g[%d] -> '%s' but has bad format ('%c')\n", test,
+         precision, buffer, buffer[index]);
+         failed = 1;
+      }
+      else if (PNG_FP_IS_NEGATIVE(state) && !(test < 0))
+      {
+         fprintf(stderr, "%g[%d] -> '%s' but negative value not so reported\n",
+            test, precision, buffer);
+         failed = 1;
+         assert(!PNG_FP_IS_ZERO(state));
+         assert(!PNG_FP_IS_POSITIVE(state));
+      }
+      else if (PNG_FP_IS_ZERO(state) && !(test == 0))
+      {
+         fprintf(stderr, "%g[%d] -> '%s' but zero value not so reported\n",
+            test, precision, buffer);
+         failed = 1;
+         assert(!PNG_FP_IS_NEGATIVE(state));
+         assert(!PNG_FP_IS_POSITIVE(state));
+      }
+      else if (PNG_FP_IS_POSITIVE(state) && !(test > 0))
+      {
+         fprintf(stderr, "%g[%d] -> '%s' but postive value not so reported\n",
+            test, precision, buffer);
+         failed = 1;
+         assert(!PNG_FP_IS_NEGATIVE(state));
+         assert(!PNG_FP_IS_ZERO(state));
+      }
+      else
+      {
+         /* Check the result against the original. */
+         double out = atof(buffer);
+         double change = fabs((out - test)/test);
+         double allow = .5/pow(10,
+            (precision >= DBL_DIG) ? DBL_DIG-1 : precision-1);
+
+         /* NOTE: if you hit this error case are you compiling with gcc
+          * and -O0?  Try -O2 - the errors can accumulate if the FP
+          * code above is not optimized and may drift outside the .5 in
+          * DBL_DIG allowed.  In any case a small number of errors may
+          * occur (very small ones - 1 or 2%) because of rounding in the
+          * calculations, either in the conversion API or in atof.
+          */
+         if (change >= allow && (isfinite(out) ||
+             fabs(test/DBL_MAX) <= 1-allow))
+         {
+            double percent = (precision >= DBL_DIG) ? max_error_abs : max_error;
+            double allowp = (change-allow)*100/allow;
+
+            if (precision >= DBL_DIG)
+            {
+               if (max_abs < allowp) max_abs = allowp;
+            }
+
+            else
+            {
+               if (max < allowp) max = allowp;
+            }
+
+            if (showall || allowp >= percent)
+            {
+               fprintf(stderr,
+                  "%.*g[%d] -> '%s' -> %.*g number changed (%g > %g (%d%%))\n",
+                  DBL_DIG, test, precision, buffer, DBL_DIG, out, change, allow,
+                  (int)round(allowp));
+               failed = 1;
+            }
+            else
+               ++minorarith;
+         }
+      }
+
+      if (failed)
+         ++failcount;
+      else
+         ++ok;
+
+skip:
+      /* Generate a new number and precision. */
+      precision = rand();
+      if (precision & 1) test = -test;
+      precision >>= 1;
+
+      /* Generate random numbers. */
+      if (test == 0 || !isfinite(test))
+         test = precision+1;
+      else
+      {
+         /* Derive the exponent from the previous rand() value. */
+         int exponent = precision % (DBL_MAX_EXP - DBL_MIN_EXP) + DBL_MIN_EXP;
+         int tmp;
+         test = frexp(test * rand(), &tmp);
+         test = ldexp(test, exponent);
+         precision >>= 8; /* arbitrary */
+      }
+
+      /* This limits the precision to 32 digits, enough for standard
+       * IEEE implementations which have at most 15 digits.
+       */
+      precision = (precision & 0x1f) + 1;
+   }
+   while (--count);
+
+   printf("Tested %d finite values, %d non-finite, %d OK (%d failed) %d minor "
+      "arithmetic errors\n", finite, nonfinite, ok, failcount, minorarith);
+   printf(" Error with >=%d digit precision %.2f%%\n", DBL_DIG, max_abs);
+   printf(" Error with < %d digit precision %.2f%%\n", DBL_DIG, max);
+
+   return 0;
+}
+
+/* Observe that valid FP numbers have the forms listed in the PNG extensions
+ * specification:
+ *
+ * [+,-]{integer,integer.fraction,.fraction}[{e,E}[+,-]integer]
+ *
+ * Test each of these in turn, including invalid cases.
+ */
+typedef enum checkfp_state
+{
+   start, fraction, exponent, states
+} checkfp_state;
+
+/* The characters (other than digits) that characterize the states: */
+static const char none[] = "";
+static const char hexdigits[16] = "0123456789ABCDEF";
+
+static const struct
+{
+   const char *start; /* Characters valid at the start */
+   const char *end;   /* Valid characters that end the state */
+   const char *tests; /* Characters to test after 2 digits seen */
+}
+state_characters[states] =
+{
+   /* start:    */ { "+-.", ".eE", "+-.e*0369" },
+   /* fraction: */ { none, "eE",  "+-.E#0147" },
+   /* exponent: */ { "+-", none,  "+-.eE^0258" }
+};
+
+typedef struct
+{
+   char number[1024];  /* Buffer for number being tested */
+   int  limit;         /* Command line limit */
+   int  verbose;       /* Shadows global variable */
+   int  ctimes;        /* Number of numbers tested */
+   int  cmillions;     /* Count of millions of numbers */
+   int  cinvalid;      /* Invalid strings checked */
+   int  cnoaccept;     /* Characters not accepted */
+}
+checkfp_command;
+
+typedef struct
+{
+   int           cnumber;          /* Index into number string */
+   checkfp_state check_state;      /* Current number state */
+   int           at_start;         /* At start (first character) of state */
+   int           cdigits_in_state; /* Digits seen in that state */
+   int           limit;            /* Limit on same for checking all chars */
+   int           state;            /* Current parser state */
+   int           is_negative;      /* Number is negative */
+   int           is_zero;          /* Number is (still) zero */
+   int           number_was_valid; /* Previous character validity */
+}
+checkfp_control;
+
+static int check_all_characters(checkfp_command *co, checkfp_control c);
+
+static int check_some_characters(checkfp_command *co, checkfp_control c,
+   const char *tests);
+
+static int check_one_character(checkfp_command *co, checkfp_control c, int ch)
+{
+   /* Test this character (ch) to ensure the parser does the correct thing.
+    */
+   png_size_t index = 0;
+   const char test = (char)ch;
+   const int number_is_valid = png_check_fp_number(&test, 1, &c.state, &index);
+   const int character_accepted = (index == 1);
+
+   if (c.check_state != exponent && isdigit(ch) && ch != '0')
+      c.is_zero = 0;
+
+   if (c.check_state == start && c.at_start && ch == '-')
+      c.is_negative = 1;
+
+   if (isprint(ch))
+      co->number[c.cnumber++] = (char)ch;
+   else
+   {
+      co->number[c.cnumber++] = '<';
+      co->number[c.cnumber++] = hexdigits[(ch >> 4) & 0xf];
+      co->number[c.cnumber++] = hexdigits[ch & 0xf];
+      co->number[c.cnumber++] = '>';
+   }
+   co->number[c.cnumber] = 0;
+
+   if (co->verbose > 1)
+      fprintf(stderr, "%s\n", co->number);
+
+   if (++(co->ctimes) == 1000000)
+   {
+      if (co->verbose == 1)
+         fputc('.', stderr);
+      co->ctimes = 0;
+      ++(co->cmillions);
+   }
+
+   if (!number_is_valid)
+      ++(co->cinvalid);
+
+   if (!character_accepted)
+      ++(co->cnoaccept);
+
+   /* This should never fail (it's a serious bug if it does): */
+   if (index != 0 && index != 1)
+   {
+      fprintf(stderr, "%s: read beyond end of string (%lu)\n", co->number,
+         (unsigned long)index);
+      return 0;
+   }
+
+   /* Validate the new state, note that the PNG_FP_IS_ macros all return
+    * false unless the number is valid.
+    */
+   if (PNG_FP_IS_NEGATIVE(c.state) !=
+      (number_is_valid && !c.is_zero && c.is_negative))
+   {
+      fprintf(stderr, "%s: negative when it is not\n", co->number);
+      return 0;
+   }
+
+   if (PNG_FP_IS_ZERO(c.state) != (number_is_valid && c.is_zero))
+   {
+      fprintf(stderr, "%s: zero when it is not\n", co->number);
+      return 0;
+   }
+
+   if (PNG_FP_IS_POSITIVE(c.state) !=
+      (number_is_valid && !c.is_zero && !c.is_negative))
+   {
+      fprintf(stderr, "%s: positive when it is not\n", co->number);
+      return 0;
+   }
+
+   /* Testing a digit */
+   if (isdigit(ch))
+   {
+      if (!character_accepted)
+      {
+         fprintf(stderr, "%s: digit '%c' not accepted\n", co->number, ch);
+         return 0;
+      }
+
+      if (!number_is_valid)
+      {
+         fprintf(stderr, "%s: saw a digit (%c) but number not valid\n",
+            co->number, ch);
+         return 0;
+      }
+
+      ++c.cdigits_in_state;
+      c.at_start = 0;
+      c.number_was_valid = 1;
+
+      /* Continue testing characters in this state.  Either test all of
+       * them or, if we have already seen one digit in this state, just test a
+       * limited set.
+       */
+      if (c.cdigits_in_state < 1)
+         return check_all_characters(co, c);
+
+      else
+         return check_some_characters(co, c,
+            state_characters[c.check_state].tests);
+   }
+
+   /* A non-digit; is it allowed here? */
+   else if (((ch == '+' || ch == '-') && c.check_state != fraction &&
+               c.at_start) ||
+            (ch == '.' && c.check_state == start) ||
+            ((ch == 'e' || ch == 'E') && c.number_was_valid &&
+               c.check_state != exponent))
+   {
+      if (!character_accepted)
+      {
+         fprintf(stderr, "%s: character '%c' not accepted\n", co->number, ch);
+         return 0;
+      }
+
+      /* The number remains valid after start of fraction but nowhere else. */
+      if (number_is_valid && (c.check_state != start || ch != '.'))
+      {
+         fprintf(stderr, "%s: saw a non-digit (%c) but number valid\n",
+            co->number, ch);
+         return 0;
+      }
+
+      c.number_was_valid = number_is_valid;
+
+      /* Check for a state change.  When changing to 'fraction' if the number
+       * is valid at this point set the at_start to false to allow an exponent
+       * 'e' to come next.
+       */
+      if (c.check_state == start && ch == '.')
+      {
+         c.check_state = fraction;
+         c.at_start = !number_is_valid;
+         c.cdigits_in_state = 0;
+         c.limit = co->limit;
+         return check_all_characters(co, c);
+      }
+
+      else if (c.check_state < exponent && (ch == 'e' || ch == 'E'))
+      {
+         c.check_state = exponent;
+         c.at_start = 1;
+         c.cdigits_in_state = 0;
+         c.limit = co->limit;
+         return check_all_characters(co, c);
+      }
+
+      /* Else it was a sign, and the state doesn't change. */
+      else
+      {
+         if (ch != '-' && ch != '+')
+         {
+            fprintf(stderr, "checkfp: internal error (1)\n");
+            return 0;
+         }
+
+         c.at_start = 0;
+         return check_all_characters(co, c);
+      }
+   }
+
+   /* Testing an invalid character */
+   else
+   {
+      if (character_accepted)
+      {
+         fprintf(stderr, "%s: character '%c' [0x%.2x] accepted\n", co->number,
+            ch, ch);
+         return 0;
+      }
+
+      if (number_is_valid != c.number_was_valid)
+      {
+         fprintf(stderr,
+            "%s: character '%c' [0x%.2x] changed number validity\n", co->number,
+            ch, ch);
+         return 0;
+      }
+
+      /* Do nothing - the parser has stuck; return success and keep going with
+       * the next character.
+       */
+   }
+
+   /* Successful return (the caller will try the next character.) */
+   return 1;
+}
+
+static int check_all_characters(checkfp_command *co, checkfp_control c)
+{
+   int ch;
+
+   if (c.cnumber+4 < sizeof co->number) for (ch=0; ch<256; ++ch)
+   {
+      if (!check_one_character(co, c, ch))
+         return 0;
+   }
+
+   return 1;
+}
+
+static int check_some_characters(checkfp_command *co, checkfp_control c,
+   const char *tests)
+{
+   int i;
+
+   --(c.limit);
+
+   if (c.cnumber+4 < sizeof co->number && c.limit >= 0)
+   {
+      if (c.limit > 0) for (i=0; tests[i]; ++i)
+      {
+         if (!check_one_character(co, c, tests[i]))
+               return 0;
+      }
+
+      /* At the end check all the characters. */
+      else
+         return check_all_characters(co, c);
+   }
+
+   return 1;
+}
+
+int validation_checkfp(int count, int argc, char **argv)
+{
+   int result;
+   checkfp_command command;
+   checkfp_control control;
+
+   command.number[0] = 0;
+   command.limit = 3;
+   command.verbose = verbose;
+   command.ctimes = 0;
+   command.cmillions = 0;
+   command.cinvalid = 0;
+   command.cnoaccept = 0;
+
+   while (--argc > 0)
+   {
+      ++argv;
+      if (argc > 1 && strcmp(*argv, "-l") == 0)
+      {
+         --argc;
+         command.limit = atoi(*++argv);
+      }
+
+      else
+      {
+         fprintf(stderr, "unknown argument %s\n", *argv);
+         return 1;
+      }
+   }
+
+   control.cnumber = 0;
+   control.check_state = start;
+   control.at_start = 1;
+   control.cdigits_in_state = 0;
+   control.limit = command.limit;
+   control.state = 0;
+   control.is_negative = 0;
+   control.is_zero = 1;
+   control.number_was_valid = 0;
+
+   result = check_all_characters(&command, control);
+
+   printf("checkfp: %s: checked %d,%.3d,%.3d,%.3d strings (%d invalid)\n",
+      result ? "pass" : "FAIL", command.cmillions / 1000,
+      command.cmillions % 1000, command.ctimes / 1000, command.ctimes % 1000,
+      command.cinvalid);
+
+   return result;
+}
+
+int validation_muldiv(int count, int argc, char **argv)
+{
+   int tested = 0;
+   int overflow = 0;
+   int error = 0;
+   int error64 = 0;
+   int passed = 0;
+   int randbits = 0;
+   png_uint_32 randbuffer;
+   png_fixed_point a;
+   png_int_32 times, div;
+
+   while (--argc > 0)
+      {
+         fprintf(stderr, "unknown argument %s\n", *++argv);
+         return 1;
+      }
+
+   /* Find out about the random number generator. */
+   randbuffer = RAND_MAX;
+   while (randbuffer != 0) ++randbits, randbuffer >>= 1;
+   printf("Using random number generator that makes %d bits\n", randbits);
+   for (div=0; div<32; div += randbits)
+      randbuffer = (randbuffer << randbits) ^ rand();
+
+   a = 0;
+   times = div = 0;
+   do
+   {
+      png_fixed_point result;
+      /* NOTE: your mileage may vary, a type is required below that can
+       * hold 64 bits or more, if floating point is used a 64 bit or
+       * better mantissa is required.
+       */
+      long long int fp, fpround;
+      unsigned long hi, lo;
+      int ok;
+
+      /* Check the values, png_64bit_product can only handle positive
+       * numbers, so correct for that here.
+       */
+      {
+         long u1, u2;
+         int n = 0;
+         if (a < 0) u1 = -a, n = 1; else u1 = a;
+         if (times < 0) u2 = -times, n = !n; else u2 = times;
+         png_64bit_product(u1, u2, &hi, &lo);
+         if (n)
+         {
+            /* -x = ~x+1 */
+            lo = ((~lo) + 1) & 0xffffffff;
+            hi = ~hi;
+            if (lo == 0) ++hi;
+         }
+      }
+
+      fp = a;
+      fp *= times;
+      if ((fp & 0xffffffff) != lo || ((fp >> 32) & 0xffffffff) != hi)
+      {
+         fprintf(stderr, "png_64bit_product %d * %d -> %lx|%.8lx not %llx\n",
+            a, times, hi, lo, fp);
+         ++error64;
+      }
+
+      if (div != 0)
+      {
+         /* Round - this is C round to zero. */
+         if ((fp < 0) != (div < 0))
+           fp -= div/2;
+         else
+           fp += div/2;
+
+         fp /= div;
+         fpround = fp;
+         /* Assume 2's complement here: */
+         ok = fpround <= PNG_UINT_31_MAX &&
+              fpround >= -1-(long long int)PNG_UINT_31_MAX;
+         if (!ok) ++overflow;
+      }
+      else
+        ok = 0, ++overflow, fpround = fp/*misleading*/;
+
+      if (verbose)
+         fprintf(stderr, "TEST %d * %d / %d -> %lld (%s)\n", a, times, div,
+            fp, ok ? "ok" : "overflow");
+
+      ++tested;
+      if (png_muldiv(&result, a, times, div) != ok)
+      {
+         ++error;
+         if (ok)
+             fprintf(stderr, "%d * %d / %d -> overflow (expected %lld)\n", a,
+                times, div, fp);
+         else
+             fprintf(stderr, "%d * %d / %d -> %d (expected overflow %lld)\n", a,
+                times, div, result, fp);
+      }
+      else if (ok && result != fpround)
+      {
+         ++error;
+         fprintf(stderr, "%d * %d / %d -> %d not %lld\n", a, times, div, result,
+            fp);
+      }
+      else
+         ++passed;
+
+      /* Generate three new values, this uses rand() and rand() only returns
+       * up to RAND_MAX.
+       */
+      /* CRUDE */
+      a += times;
+      times += div;
+      div = randbuffer;
+      randbuffer = (randbuffer << randbits) ^ rand();
+   }
+   while (--count > 0);
+
+   printf("%d tests including %d overflows, %d passed, %d failed (%d 64 bit "
+      "errors)\n", tested, overflow, passed, error, error64);
+   return 0;
+}
+
+/* When FP is on this just becomes a speed test - compile without FP to get real
+ * validation.
+ */
+#ifdef PNG_FLOATING_ARITHMETIC_SUPPORTED
+#define LN2 .000010576586617430806112933839 /* log(2)/65536 */
+#define L2INV 94548.46219969910586572651    /* 65536/log(2) */
+
+/* For speed testing, need the internal functions too: */
+static png_uint_32 png_log8bit(unsigned x)
+{
+   if (x > 0)
+      return (png_uint_32)floor(.5-log(x/255.)*L2INV);
+
+   return 0xffffffff;
+}
+
+static png_uint_32 png_log16bit(png_uint_32 x)
+{
+   if (x > 0)
+      return (png_uint_32)floor(.5-log(x/65535.)*L2INV);
+
+   return 0xffffffff;
+}
+
+static png_uint_32 png_exp(png_uint_32 x)
+{
+   return (png_uint_32)floor(.5 + exp(x * -LN2) * 0xffffffffU);
+}
+
+static png_byte png_exp8bit(png_uint_32 log)
+{
+   return (png_byte)floor(.5 + exp(log * -LN2) * 255);
+}
+
+static png_uint_16 png_exp16bit(png_uint_32 log)
+{
+   return (png_uint_16)floor(.5 + exp(log * -LN2) * 65535);
+}
+#endif /* FLOATING_ARITHMETIC */
+
+int validation_gamma(int argc, char **argv)
+{
+   double gamma[9] = { 2.2, 1.8, 1.52, 1.45, 1., 1/1.45, 1/1.52, 1/1.8, 1/2.2 };
+   double maxerr;
+   int i, silent=0, onlygamma=0;
+
+   /* Silence the output with -s, just test the gamma functions with -g: */
+   while (--argc > 0)
+      if (strcmp(*++argv, "-s") == 0)
+         silent = 1;
+      else if (strcmp(*argv, "-g") == 0)
+         onlygamma = 1;
+      else
+      {
+         fprintf(stderr, "unknown argument %s\n", *argv);
+         return 1;
+      }
+
+   if (!onlygamma)
+   {
+      /* First validate the log functions: */
+      maxerr = 0;
+      for (i=0; i<256; ++i)
+      {
+         double correct = -log(i/255.)/log(2.)*65536;
+         double error = png_log8bit(i) - correct;
+
+         if (i != 0 && fabs(error) > maxerr)
+            maxerr = fabs(error);
+
+         if (i == 0 && png_log8bit(i) != 0xffffffff ||
+             i != 0 && png_log8bit(i) != floor(correct+.5))
+         {
+            fprintf(stderr, "8 bit log error: %d: got %u, expected %f\n",
+               i, png_log8bit(i), correct);
+         }
+      }
+
+      if (!silent)
+         printf("maximum 8 bit log error = %f\n", maxerr);
+
+      maxerr = 0;
+      for (i=0; i<65536; ++i)
+      {
+         double correct = -log(i/65535.)/log(2.)*65536;
+         double error = png_log16bit(i) - correct;
+
+         if (i != 0 && fabs(error) > maxerr)
+            maxerr = fabs(error);
+
+         if (i == 0 && png_log16bit(i) != 0xffffffff ||
+             i != 0 && png_log16bit(i) != floor(correct+.5))
+         {
+            if (error > .68) /* By experiment error is less than .68 */
+            {
+               fprintf(stderr, "16 bit log error: %d: got %u, expected %f"
+                  " error: %f\n", i, png_log16bit(i), correct, error);
+            }
+         }
+      }
+
+      if (!silent)
+         printf("maximum 16 bit log error = %f\n", maxerr);
+
+      /* Now exponentiations. */
+      maxerr = 0;
+      for (i=0; i<=0xfffff; ++i)
+      {
+         double correct = exp(-i/65536. * log(2.)) * (65536. * 65536);
+         double error = png_exp(i) - correct;
+
+         if (fabs(error) > maxerr)
+            maxerr = fabs(error);
+         if (fabs(error) > 1883) /* By experiment. */
+         {
+            fprintf(stderr, "32 bit exp error: %d: got %u, expected %f"
+                  " error: %f\n", i, png_exp(i), correct, error);
+         }
+      }
+
+      if (!silent)
+         printf("maximum 32 bit exp error = %f\n", maxerr);
+
+      maxerr = 0;
+      for (i=0; i<=0xfffff; ++i)
+      {
+         double correct = exp(-i/65536. * log(2.)) * 255;
+         double error = png_exp8bit(i) - correct;
+
+         if (fabs(error) > maxerr)
+            maxerr = fabs(error);
+         if (fabs(error) > .50002) /* By experiment */
+         {
+            fprintf(stderr, "8 bit exp error: %d: got %u, expected %f"
+                  " error: %f\n", i, png_exp8bit(i), correct, error);
+         }
+      }
+
+      if (!silent)
+         printf("maximum 8 bit exp error = %f\n", maxerr);
+
+      maxerr = 0;
+      for (i=0; i<=0xfffff; ++i)
+      {
+         double correct = exp(-i/65536. * log(2.)) * 65535;
+         double error = png_exp16bit(i) - correct;
+
+         if (fabs(error) > maxerr)
+            maxerr = fabs(error);
+         if (fabs(error) > .524) /* By experiment */
+         {
+            fprintf(stderr, "16 bit exp error: %d: got %u, expected %f"
+                  " error: %f\n", i, png_exp16bit(i), correct, error);
+         }
+      }
+
+      if (!silent)
+         printf("maximum 16 bit exp error = %f\n", maxerr);
+   } /* !onlygamma */
+
+   /* Test the overall gamma correction. */
+   for (i=0; i<9; ++i)
+   {
+      unsigned j;
+      double g = gamma[i];
+      png_fixed_point gfp = floor(g * PNG_FP_1 + .5);
+
+      if (!silent)
+         printf("Test gamma %f\n", g);
+
+      maxerr = 0;
+      for (j=0; j<256; ++j)
+      {
+         double correct = pow(j/255., g) * 255;
+         png_byte out = png_gamma_8bit_correct(j, gfp);
+         double error = out - correct;
+
+         if (fabs(error) > maxerr)
+            maxerr = fabs(error);
+         if (out != floor(correct+.5))
+         {
+            fprintf(stderr, "8bit %d ^ %f: got %d expected %f error %f\n",
+               j, g, out, correct, error);
+         }
+      }
+
+      if (!silent)
+         printf("gamma %f: maximum 8 bit error %f\n", g, maxerr);
+
+      maxerr = 0;
+      for (j=0; j<65536; ++j)
+      {
+         double correct = pow(j/65535., g) * 65535;
+         png_uint_16 out = png_gamma_16bit_correct(j, gfp);
+         double error = out - correct;
+
+         if (fabs(error) > maxerr)
+            maxerr = fabs(error);
+         if (fabs(error) > 1.62)
+         {
+            fprintf(stderr, "16bit %d ^ %f: got %d expected %f error %f\n",
+               j, g, out, correct, error);
+         }
+      }
+
+      if (!silent)
+         printf("gamma %f: maximum 16 bit error %f\n", g, maxerr);
+   }
+
+   return 0;
+}
+
+/**************************** VALIDATION TESTS ********************************/
+/* Various validation routines are included herein, they require some
+ * definition for png_warning and png_error, seetings of VALIDATION:
+ *
+ * 1: validates the ASCII to floating point conversions
+ * 2: validates png_muldiv
+ * 3: accuracy test of fixed point gamma tables
+ */
+
+/* The following COUNT (10^8) takes about 1 hour on a 1GHz Pentium IV
+ * processor.
+ */
+#define COUNT 1000000000
+
+int main(int argc, char **argv)
+{
+   int count = COUNT;
+
+   while (argc > 1)
+   {
+      if (argc > 2 && strcmp(argv[1], "-c") == 0)
+      {
+         count = atoi(argv[2]);
+         argc -= 2;
+         argv += 2;
+      }
+
+      else if (strcmp(argv[1], "-v") == 0)
+      {
+         ++verbose;
+         --argc;
+         ++argv;
+      }
+
+      else
+         break;
+   }
+
+   if (count > 0 && argc > 1)
+   {
+      if (strcmp(argv[1], "ascii") == 0)
+         return validation_ascii_to_fp(count, argc-1, argv+1);
+      else if (strcmp(argv[1], "checkfp") == 0)
+         return validation_checkfp(count, argc-1, argv+1);
+      else if (strcmp(argv[1], "muldiv") == 0)
+         return validation_muldiv(count, argc-1, argv+1);
+      else if (strcmp(argv[1], "gamma") == 0)
+         return validation_gamma(argc-1, argv+1);
+   }
+
+   /* Bad argument: */
+   fprintf(stderr,
+      "usage: tarith [-v] [-c count] {ascii,muldiv,gamma} [args]\n");
+   fprintf(stderr, " arguments: ascii [-a (all results)] [-e error%%]\n");
+   fprintf(stderr, "            checkfp [-l max-number-chars]\n");
+   fprintf(stderr, "            muldiv\n");
+   fprintf(stderr, "            gamma -s (silent) -g (only gamma; no log)\n");
+   return 1;
+}

contrib/libtests/test-pngstest.sh

@@ -0,0 +1,24 @@
+#!/bin/sh
+#
+# Run the simplified API tests
+err=0
+
+echo >> pngtest-log.txt
+echo "============ pngstest.sh ==============" >> pngtest-log.txt
+
+echo "Running test-pngstest.sh"
+for image in ${srcdir}/contrib/pngsuite/*.png
+do
+   for opts in ""
+   do
+      if ./pngstest --strict --log "$@" $opts $image >>pngtest-log.txt 2>&1
+      then
+         echo "  PASS: pngstest $opts $image"
+      else
+         echo "  FAIL: pngstest $opts $image"
+         err=1
+      fi
+   done
+done
+
+exit $err

contrib/libtests/test-pngunknown.sh

@@ -0,0 +1,38 @@
+#!/bin/sh
+#
+# Run the unknown API tests
+err=0
+image="${srcdir}/pngtest.png"
+#
+# stream 4 is used for the output of the shell, pngtest-log.txt gets all the
+# normal program output.
+exec 4>&1 1>>pngtest-log.txt 2>&1
+
+echo
+echo "============ test-pngunknown.sh =============="
+
+echo "Running test-pngunknown.sh" >&4
+
+for tests in \
+ "discard default=discard"\
+ "save default=save"\
+ "if-safe default=if-safe"\
+ "vpAg vpAg=if-safe"\
+ "sTER sTER=if-safe"\
+ "IDAT default=discard IDAT=save"\
+ "sAPI bKGD=save cHRM=save gAMA=save all=discard iCCP=save sBIT=save sRGB=save"
+do
+   set $tests
+   test="$1"
+   shift
+
+   if ./pngunknown "$@" "$image" 4>&-
+   then
+      echo "  PASS: test-pngunknown $test" >&4
+   else
+      echo "  FAIL: test-pngunknown $test" >&4
+      err=1
+   fi
+done
+
+exit $err

contrib/libtests/test-pngvalid-full.sh

@@ -0,0 +1,21 @@
+#!/bin/sh
+#
+# Run a sequence of gamma tests quietly
+err=0
+
+echo >> pngtest-log.txt
+echo "============ pngvalid-full.sh ==============" >> pngtest-log.txt
+
+echo "Running test-pngvalid-full.sh"
+for gamma in threshold transform sbit 16-to-8 background alpha-mode "transform --expand16" "background --expand16" "alpha-mode --expand16"
+do
+   if ./pngvalid "$@" --gamma-$gamma >> pngtest-log.txt 2>&1
+   then
+      echo "  PASS: pngvalid" "$@" "--gamma-$gamma"
+   else
+      echo "  FAIL: pngvalid" "$@" "--gamma-$gamma"
+      err=1
+   fi
+done
+
+exit $err

contrib/libtests/test-pngvalid-simple.sh

@@ -0,0 +1,30 @@
+#!/bin/sh
+#
+# Run a sequence of tests quietly, without the slow
+# gamma tests
+err=0
+
+echo >> pngtest-log.txt
+echo "============ pngvalid-simple.sh ==============" >> pngtest-log.txt
+echo "Running test-pngvalid-simple.sh"
+# The options to test are:
+#
+# standard tests with and without progressive reading and interlace
+# size images with and without progressive reading
+# transform tests (standard, non-interlaced only)
+#
+for opts in "--standard" "--standard --progressive-read" \
+   "--standard --interlace" "--standard --progressive-read --interlace" \
+   "--size" "--size --progressive-read" \
+   "--transform"
+do
+   if ./pngvalid "$@" $opts >> pngtest-log.txt 2>&1
+   then
+      echo "  PASS: pngvalid" "$@" $opts
+   else
+      echo "  FAIL: pngvalid" "$@" $opts
+      err=1
+   fi
+done
+
+exit $err

contrib/libtests/timepng.c

@@ -0,0 +1,303 @@
+/* timepng.c
+ *
+ * Copyright (c) 2012 John Cunningham Bowler
+ *
+ * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Load an arbitrary number of PNG files (from the command line, or, if there
+ * are no arguments on the command line, from stdin) then run a time test by
+ * reading each file by row.  The test does nothing with the read result and
+ * does no transforms.  The only output is a time as a floating point number of
+ * seconds with 9 decimal digits.
+ */
+#define _POSIX_C_SOURCE 199309L /* for clock_gettime */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <time.h>
+
+#if (defined HAVE_CONFIG_H) && !(defined PNG_NO_CONFIG_H)
+#  include <config.h>
+#endif
+
+/* Define the following to use this test against your installed libpng, rather
+ * than the one being built here:
+ */
+#ifdef PNG_FREESTANDING_TESTS
+#  include <png.h>
+#else
+#  include "../../png.h"
+#endif
+
+static int read_png(FILE *fp)
+{
+   png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);
+   png_infop info_ptr = NULL;
+   png_bytep row = NULL, display = NULL;
+
+   if (png_ptr == NULL)
+      return 0;
+
+   if (setjmp(png_jmpbuf(png_ptr)))
+   {
+      png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+      if (row != NULL) free(row);
+      if (display != NULL) free(display);
+      return 0;
+   }
+
+   png_init_io(png_ptr, fp);
+
+   info_ptr = png_create_info_struct(png_ptr);
+   if (info_ptr == NULL)
+      png_error(png_ptr, "OOM allocating info structure");
+
+   png_read_info(png_ptr, info_ptr);
+
+   {
+      png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+
+      row = malloc(rowbytes);
+      display = malloc(rowbytes);
+
+      if (row == NULL || display == NULL)
+         png_error(png_ptr, "OOM allocating row buffers");
+
+      {
+         png_uint_32 height = png_get_image_height(png_ptr, info_ptr);
+         int passes = png_set_interlace_handling(png_ptr);
+         int pass;
+
+         png_start_read_image(png_ptr);
+
+         for (pass = 0; pass < passes; ++pass)
+         {
+            png_uint_32 y = height;
+
+            /* NOTE: this trashes the row each time; interlace handling won't
+             * work, but this avoids memory thrashing for speed testing.
+             */
+            while (y-- > 0)
+               png_read_row(png_ptr, row, display);
+         }
+      }
+   }
+
+   /* Make sure to read to the end of the file: */
+   png_read_end(png_ptr, info_ptr);
+   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+   free(row);
+   free(display);
+   return 1;
+}
+
+static int mytime(struct timespec *t)
+{
+   /* Do the timing using clock_gettime and the per-process timer. */
+   if (!clock_gettime(CLOCK_PROCESS_CPUTIME_ID, t))
+      return 1;
+
+   perror("CLOCK_PROCESS_CPUTIME_ID");
+   fprintf(stderr, "timepng: could not get the time\n");
+   return 0;
+}
+
+static int perform_one_test(FILE *fp, int nfiles)
+{
+   int i;
+   struct timespec before, after;
+
+   /* Clear out all errors: */
+   rewind(fp);
+
+   if (mytime(&before))
+   {
+      for (i=0; i<nfiles; ++i)
+      {
+         if (read_png(fp))
+         {
+            if (ferror(fp))
+            {
+               perror("temporary file");
+               fprintf(stderr, "file %d: error reading PNG data\n", i);
+               return 0;
+            }
+         }
+
+         else
+         {
+            perror("temporary file");
+            fprintf(stderr, "file %d: error from libpng\n", i);
+            return 0;
+         }
+      }
+   }
+
+   else
+      return 0;
+
+   if (mytime(&after))
+   {
+      /* Work out the time difference and print it - this is the only output,
+       * so flush it immediately.
+       */
+      unsigned long s = after.tv_sec - before.tv_sec;
+      long ns = after.tv_nsec - before.tv_nsec;
+
+      if (ns < 0)
+      {
+         --s;
+         ns += 1000000000;
+
+         if (ns < 0)
+         {
+            fprintf(stderr, "timepng: bad clock from kernel\n");
+            return 0;
+         }
+      }
+
+      printf("%lu.%.9ld\n", s, ns);
+      fflush(stdout);
+      if (ferror(stdout))
+      {
+         fprintf(stderr, "timepng: error writing output\n");
+         return 0;
+      }
+
+      /* Successful return */
+      return 1;
+   }
+
+   else
+      return 0;
+}
+
+static int add_one_file(FILE *fp, char *name)
+{
+   FILE *ip = fopen(name, "rb");
+
+   if (ip != NULL)
+   {
+      int ch;
+      for (;;)
+      {
+         ch = getc(ip);
+         if (ch == EOF) break;
+         putc(ch, fp);
+      }
+
+      if (ferror(ip))
+      {
+         perror(name);
+         fprintf(stderr, "%s: read error\n", name);
+         return 0;
+      }
+
+      (void)fclose(ip);
+
+      if (ferror(fp))
+      {
+         perror("temporary file");
+         fprintf(stderr, "temporary file write error\n");
+         return 0;
+      }
+   }
+
+   else
+   {
+      perror(name);
+      fprintf(stderr, "%s: open failed\n", name);
+      return 0;
+   }
+
+   return 1;
+}
+
+int main(int argc, char **argv)
+{
+   int ok = 0;
+   FILE *fp = tmpfile();
+
+   if (fp != NULL)
+   {
+      int err = 0;
+      int nfiles = 0;
+
+      if (argc > 1)
+      {
+         int i;
+
+         for (i=1; i<argc; ++i)
+         {
+            if (add_one_file(fp, argv[i]))
+               ++nfiles;
+
+            else
+            {
+               err = 1;
+               break;
+            }
+         }
+      }
+
+      else
+      {
+         char filename[FILENAME_MAX+1];
+
+         while (fgets(filename, FILENAME_MAX+1, stdin))
+         {
+            size_t len = strlen(filename);
+
+            if (filename[len-1] == '\n')
+            {
+               filename[len-1] = 0;
+               if (add_one_file(fp, filename))
+                  ++nfiles;
+
+               else
+               {
+                  err = 1;
+                  break;
+               }
+            }
+
+            else
+            {
+               fprintf(stderr, "timepng: truncated file name ...%s\n",
+                  filename+len-32);
+               err = 1;
+               break;
+            }
+         }
+
+         if (ferror(stdin))
+         {
+            fprintf(stderr, "timepng: stdin: read error\n");
+            err = 1;
+         }
+      }
+
+      if (!err)
+      {
+         if (nfiles > 0)
+            ok = perform_one_test(fp, nfiles);
+
+         else
+            fprintf(stderr, "usage: timepng {files} or ls files | timepng\n");
+      }
+
+      (void)fclose(fp);
+   }
+
+   else
+      fprintf(stderr, "timepng: could not open temporary file\n");
+
+   /* Exit code 0 on success. */
+   return ok == 0;
+}

contrib/pngminim/README

@@ -0,0 +1,5 @@
+
+This demonstrates the use of PNG_USER_CONFIG, pngusr.h and pngusr.dfa
+to build minimal decoder, encoder, and progressive reader applications.
+
+See the individual README and pngusr.dfa files for more explanation.

contrib/pngminim/decoder/README

@@ -0,0 +1,10 @@
+This demonstrates the use of PNG_USER_CONFIG, pngusr.h and pngusr.dfa
+
+The makefile builds a minimal read-only decoder with embedded libpng
+and zlib.
+
+Specify the location of the zlib source (1.2.1 or later) as ZLIBSRC
+on the make command line.
+
+If you prefer to use the shared libraries, go to contrib/pngminus
+and build the png2pnm application there.

contrib/pngminim/decoder/makefile

@@ -0,0 +1,150 @@
+# Makefile for PngMinus (pngm2pnm)
+# Linux / Unix
+
+#CC=cc
+CC=gcc
+LD=$(CC)
+
+# If awk fails try
+# make AWK=nawk
+
+# If cpp fails try
+# make CPP=/lib/cpp
+
+RM=rm -f
+COPY=cp
+
+CFLAGS=-DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP -I. -O1
+
+C=.c
+O=.o
+L=.a
+E=
+
+# Where to find the source code:
+PNGSRC =../../..
+ZLIBSRC=$(PNGSRC)/../zlib
+PROGSRC=$(PNGSRC)/contrib/pngminus
+
+# Zlib (minimal inflate requirements - crc32 is used by libpng)
+# zutil can be eliminated if you provide your own zcalloc and zcfree
+ZSRCS  = adler32$(C) crc32$(C) \
+	 inffast$(C) inflate$(C) inftrees$(C) \
+	 zutil$(C)
+
+# Standard headers
+ZH     = zlib.h crc32.h inffast.h inffixed.h \
+	 inflate.h inftrees.h zutil.h
+
+# Machine generated headers
+ZCONF  = zconf.h
+
+# Headers callers use
+ZINC   = zlib.h $(ZCONF)
+
+# Headers the Zlib source uses
+ZHDRS  = $(ZH) $(ZCONF)
+
+ZOBJS  = adler32$(O) crc32$(O) \
+	 inffast$(O) inflate$(O) inftrees$(O) \
+	 zutil$(O)
+
+# libpng
+PNGSRCS=png$(C) pngerror$(C) pngget$(C) pngmem$(C) \
+	pngread$(C) pngrio$(C) pngrtran$(C) pngrutil$(C) \
+	pngset$(C) pngtrans$(C)
+	
+# Standard headers
+PNGH   =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
+
+# Machine generated headers
+PNGCONF=pnglibconf.h
+
+# Headers callers use
+PNGINC= png.h pngconf.h pngusr.h $(PNGCONF)
+
+# Headers the PNG library uses
+PNGHDRS=$(PNGH) $(PNGCONF) pngusr.h
+
+PNGOBJS=png$(O) pngerror$(O) pngget$(O) pngmem$(O) \
+	pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) \
+	pngset$(O) pngtrans$(O)
+
+PROGSRCS= pngm2pnm$(C)
+PROGHDRS=
+PROGDOCS=
+PROGOBJS= pngm2pnm$(O)
+
+OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
+
+# implicit make rules -------------------------------------------------------
+
+# note: dependencies do not work on implicit rule lines
+.c$(O):
+	$(CC) -c $(CFLAGS) $<
+
+# dependencies
+
+all: pngm2pnm$(E)
+
+pngm2pnm$(E): $(OBJS)
+	$(LD) -o pngm2pnm$(E) $(OBJS)
+
+# The DFA_XTRA setting turns all libpng options off then
+# turns on those required for this minimal build.
+# The CPP_FLAGS setting causes pngusr.h to be included in
+# both the build of pnglibconf.h and, subsequently, when
+# building libpng itself.
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+	$(PNGSRC)/scripts/pnglibconf.dfa \
+	$(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
+	$(RM) pnglibconf.h pnglibconf.dfn
+	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+	    DFA_XTRA="pngusr.dfa" $@
+
+clean:
+	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+	    srcdir=$(PNGSRC) clean
+	$(RM) pngm2pnm$(O)
+	$(RM) pngm2pnm$(E)
+	$(RM) $(OBJS)
+
+# distclean also removes the copied source and headers
+distclean: clean
+	$(RM) -r scripts # historical reasons
+	$(RM) $(PNGSRCS) $(PNGH)
+	$(RM) $(ZSRCS) $(ZH) $(ZCONF)
+	$(RM) $(PROGSRCS) $(PROGHDRS) $(PROGDOCS)
+
+# Header file dependencies:
+$(PROGOBJS): $(PROGHDRS) $(PNGINC) $(ZINC)
+$(PNGOBJS): $(PNGHDRS) $(ZINC)
+$(ZOBJS): $(ZHDRS)
+
+# Gather the source code from the respective directories
+$(PNGSRCS) $(PNGH): $(PNGSRC)/$@
+	$(RM) $@
+	$(COPY) $(PNGSRC)/$@ $@
+
+# No dependency on the ZLIBSRC target so that it only needs
+# to be specified once.
+$(ZSRCS) $(ZH):
+	$(RM) $@
+	$(COPY) $(ZLIBSRC)/$@ $@
+
+# The unconfigured zconf.h varies in name according to the
+# zlib release
+$(ZCONF):
+	$(RM) $@
+	@for f in zconf.h.in zconf.in.h zconf.h; do\
+	    test -r $(ZLIBSRC)/$$f &&\
+	    echo $(COPY) $(ZLIBSRC)/$$f $@ &&\
+	    $(COPY) $(ZLIBSRC)/$$f $@ && exit 0;\
+	done; echo copy: $(ZLIBSRC)/zconf.h not found; exit 1
+
+pngm2pnm.c: $(PROGSRC)/png2pnm.c
+	$(RM) $@
+	$(COPY) $(PROGSRC)/png2pnm.c $@
+
+# End of makefile for pngm2pnm

contrib/pngminim/decoder/pngusr.dfa

@@ -0,0 +1,40 @@
+# pngminim/decoder/pngusr.dfa
+#
+# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+# First all the build options off:
+
+everything = off
+
+# All that is required is some read code. This example switches
+# on the sequential read code (see ../preader for a progressive
+# read example).
+
+option SEQUENTIAL_READ on
+
+# You must choose fixed or floating point arithmetic:
+# option FLOATING_POINT on
+
+option FIXED_POINT on
+
+# You must chose the internal fixed point implementation or to
+# use the system floating point.  The latter is considerably
+# smaller (by about 1kbyte on an x86 system):
+# option FLOATING_ARITHMETIC on
+
+option FLOATING_ARITHMETIC off
+
+# Your program will probably need other options.  The example
+# program here, pngm2pnm, requires the following.  Take a look
+# at pnglibconf.h to find out the full set of what has to be
+# enabled to make the following work.
+
+option SETJMP on
+option STDIO on
+option READ_EXPAND on
+option READ_STRIP_16_TO_8 on
+option USER_LIMITS on

contrib/pngminim/decoder/pngusr.h

@@ -0,0 +1,24 @@
+/* minrdpngconf.h: headers to make a minimal png-read-only library
+ *
+ * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Derived from pngcrush.h, Copyright 1998-2007, Glenn Randers-Pehrson
+ */
+
+#ifndef MINRDPNGCONF_H
+#define MINRDPNGCONF_H
+
+/* To include pngusr.h set -DPNG_USER_CONFIG in CPPFLAGS */
+
+/* List options to turn off features of the build that do not
+ * affect the API (so are not recorded in pnglibconf.h)
+ */
+
+#define PNG_NO_WARNINGS
+#define PNG_ALIGN_TYPE PNG_ALIGN_NONE
+
+#endif /* MINRDPNGCONF_H */

contrib/pngminim/encoder/README

@@ -0,0 +1,10 @@
+This demonstrates the use of PNG_USER_CONFIG and pngusr.h
+
+The makefile builds a minimal write-only encoder with embedded libpng
+and zlib.
+
+Specify the location of the zlib source (1.2.1 or later) as ZLIBSRC
+on the make command line.
+
+If you prefer to use the shared libraries, go to contrib/pngminus
+and build the pnm2png application there.

contrib/pngminim/encoder/makefile

@@ -0,0 +1,149 @@
+# Makefile for PngMinus (pnm2pngm)
+# Linux / Unix
+
+#CC=cc
+CC=gcc
+LD=$(CC)
+
+# If awk fails try
+# make AWK=nawk
+
+# If cpp fails try
+# make CPP=/lib/cpp
+
+RM=rm -f
+COPY=cp
+
+CFLAGS=-DPNG_USER_CONFIG -DZ_SOLO -DNO_GZIP -I. -O1
+
+C=.c
+O=.o
+L=.a
+E=
+
+# Where to find the source code:
+PNGSRC =../../..
+ZLIBSRC=$(PNGSRC)/../zlib
+PROGSRC=$(PNGSRC)/contrib/pngminus
+
+# Zlib
+ZSRCS  = adler32$(C) compress$(C) crc32$(C) deflate$(C) \
+	 trees$(C) zutil$(C)
+
+# Standard headers
+#ZH     = zlib.h crc32.h deflate.h trees.h zutil.h
+ZH     = zlib.h crc32.h deflate.h trees.h zutil.h
+
+# Machine generated headers
+ZCONF  = zconf.h
+
+# Headers callers use
+ZINC   = zlib.h $(ZCONF)
+
+# Headers the Zlib source uses
+ZHDRS  = $(ZH) $(ZCONF)
+
+# compress is not required; it is needed to link the zlib
+# code because deflate defines an unused API function deflateBound
+# which itself calls compressBound from compress.
+ZOBJS  = adler32$(O) compress$(O) crc32$(O) deflate$(O) \
+	 trees$(O) zutil$(O)
+
+# libpng
+PNGSRCS=png$(C) pngerror$(C) pngget$(C) pngmem$(C) \
+	pngset$(C) pngtrans$(C) pngwio$(C) pngwrite$(C) \
+	pngwtran$(C) pngwutil$(C)
+
+# Standard headers
+PNGH   =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
+
+# Machine generated headers
+PNGCONF=pnglibconf.h
+
+# Headers callers use
+PNGINC= png.h pngconf.h pngusr.h $(PNGCONF)
+
+# Headers the PNG library uses
+PNGHDRS=$(PNGH) $(PNGCONF) pngusr.h
+
+PNGOBJS=png$(O) pngerror$(O) pngget$(O) pngmem$(O) \
+	pngset$(O) pngtrans$(O) pngwio$(O) pngwrite$(O) \
+	pngwtran$(O) pngwutil$(O)
+
+PROGSRCS= pnm2pngm$(C)
+PROGHDRS=
+PROGDOCS=
+PROGOBJS= pnm2pngm$(O)
+
+OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+	$(CC) -c $(CFLAGS) $<
+
+# dependencies
+
+all: pnm2pngm$(E)
+
+pnm2pngm$(E): $(OBJS)
+	$(LD) -o pnm2pngm$(E) $(OBJS)
+
+# The DFA_XTRA setting turns all libpng options off then
+# turns on those required for this minimal build.
+# The CPP_FLAGS setting causes pngusr.h to be included in
+# both the build of pnglibconf.h and, subsequently, when
+# building libpng itself.
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+	$(PNGSRC)/scripts/pnglibconf.dfa \
+	$(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
+	$(RM) pnglibconf.h pnglibconf.dfn
+	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+	    DFA_XTRA="pngusr.dfa" $@
+
+clean:
+	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+	    srcdir=$(PNGSRC) clean
+	$(RM) pnm2pngm$(O)
+	$(RM) pnm2pngm$(E)
+	$(RM) $(OBJS)
+
+# distclean also removes the copied source and headers
+distclean: clean
+	$(RM) -r scripts # historical reasons
+	$(RM) $(PNGSRCS) $(PNGH)
+	$(RM) $(ZSRCS) $(ZH) $(ZCONF)
+	$(RM) $(PROGSRCS) $(PROGHDRS) $(PROGDOCS)
+
+# Header file dependencies:
+$(PROGOBJS): $(PROGHDRS) $(PNGINC) $(ZINC)
+$(PNGOBJS): $(PNGHDRS) $(ZINC)
+$(ZOBJS): $(ZHDRS)
+
+# Gather the source code from the respective directories
+$(PNGSRCS) $(PNGH): $(PNGSRC)/$@
+	$(RM) $@
+	$(COPY) $(PNGSRC)/$@ $@
+
+# No dependency on the ZLIBSRC target so that it only needs
+# to be specified once.
+$(ZSRCS) $(ZH):
+	$(RM) $@
+	$(COPY) $(ZLIBSRC)/$@ $@
+
+# The unconfigured zconf.h varies in name according to the
+# zlib release
+$(ZCONF):
+	$(RM) $@
+	@for f in zconf.h.in zconf.in.h zconf.h; do\
+	    test -r $(ZLIBSRC)/$$f &&\
+	    echo $(COPY) $(ZLIBSRC)/$$f $@ &&\
+	    $(COPY) $(ZLIBSRC)/$$f $@ && exit 0;\
+	done; echo copy: $(ZLIBSRC)/zconf.h not found; exit 1
+
+pnm2pngm.c: $(PROGSRC)/pnm2png.c
+	$(RM) $@
+	$(COPY) $(PROGSRC)/pnm2png.c $@
+
+# End of makefile for pnm2pngm

contrib/pngminim/encoder/pngusr.dfa

@@ -0,0 +1,35 @@
+# pngminim/encoder/pngusr.dfa
+#
+# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+# First all the build options off:
+
+everything = off
+
+# Switch on the write code - this makes a minimalist encoder
+
+option WRITE on
+
+# You must choose fixed or floating point arithmetic:
+# option FLOATING_POINT on
+
+option FIXED_POINT on
+
+# You must chose the internal fixed point implementation or to
+# use the system floating point.  The latter is considerably
+# smaller (by about 1kbyte on an x86 system):
+# option FLOATING_ARITHMETIC on
+
+option FLOATING_ARITHMETIC off
+
+# Your program will probably need other options.  The example
+# program here, pnm2pngm, requires the following.  Take a look
+# at pnglibconf.h to find out the full set of what has to be
+# enabled to make the following work.
+
+option SETJMP on
+option STDIO on

contrib/pngminim/encoder/pngusr.h

@@ -0,0 +1,24 @@
+/* minwrpngconf.h: headers to make a minimal png-write-only library
+ *
+ * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Derived from pngcrush.h, Copyright 1998-2007, Glenn Randers-Pehrson
+ */
+
+#ifndef MINWRPNGCONF_H
+#define MINWRPNGCONF_H
+
+/* To include pngusr.h set -DPNG_USER_CONFIG in CPPFLAGS */
+
+/* List options to turn off features of the build that do not
+ * affect the API (so are not recorded in pnglibconf.h)
+ */
+
+#define PNG_NO_WARNINGS
+#define PNG_ALIGN_TYPE PNG_ALIGN_NONE
+
+#endif /* MINWRPNGCONF_H */

contrib/pngminim/preader/README

@@ -0,0 +1,15 @@
+This demonstrates the use of PNG_USER_CONFIG and pngusr.h
+
+The makefile builds a minimal read-only progressive decoder with
+embedded libpng, zlib and your system's X library.
+
+Specify the location of the zlib source (1.2.1 or later) as ZLIBSRC
+on the make command line.
+
+Edit makefile if required, to find your X library and include files,
+then
+
+    make ZLIBSRC=directory
+
+If you prefer to use the shared libraries, go to contrib/gregbook
+and build the rpng2-x application there.

contrib/pngminim/preader/makefile

@@ -0,0 +1,165 @@
+# Makefile for PngMinus (rpng2)
+# Linux / Unix
+
+#CC=cc
+CC=gcc
+LD=$(CC)
+
+# If awk fails try
+# make AWK=nawk
+
+# If cpp fails try
+# make CPP=/lib/cpp
+
+RM=rm -f
+COPY=cp
+
+#XINC = -I/usr/include			# old-style, stock X distributions
+#XLIB = -L/usr/lib/X11 -lX11		#  (including SGI IRIX)
+
+#XINC = -I/usr/openwin/include		# Sun workstations (OpenWindows)
+#XLIB = -L/usr/openwin/lib -lX11
+
+XINC = -I/usr/X11R6/include		# new X distributions (X.org, etc.)
+XLIB = -L/usr/X11R6/lib -lX11
+#XLIB = -L/usr/X11R6/lib64 -lX11	# e.g., Red Hat on AMD64
+
+#XINC = -I/usr/local/include   		# FreeBSD
+#XLIB = -L/usr/local/lib -lX11
+
+#LIBS = $(XLIB)
+LIBS = $(XLIB) -lm                      #platforms that need libm
+
+CFLAGS=-DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP -I. $(XINC) -O1
+
+C=.c
+O=.o
+L=.a
+E=
+
+# Where to find the source code:
+PNGSRC =../../..
+ZLIBSRC=$(PNGSRC)/../zlib
+PROGSRC=$(PNGSRC)/contrib/gregbook
+
+# Zlib (minimal inflate requirements - crc32 is used by libpng)
+# zutil can be eliminated if you provide your own zcalloc and zcfree
+ZSRCS  = adler32$(C) crc32$(C) \
+	 inffast$(C) inflate$(C) inftrees$(C) \
+	 zutil$(C)
+
+# Standard headers
+ZH     = zlib.h crc32.h inffast.h inffixed.h \
+	 inflate.h inftrees.h zutil.h
+
+# Machine generated headers
+ZCONF  = zconf.h
+
+# Headers callers use
+ZINC   = zlib.h $(ZCONF)
+
+# Headers the Zlib source uses
+ZHDRS  = $(ZH) $(ZCONF)
+
+ZOBJS  = adler32$(O) crc32$(O) \
+	 inffast$(O) inflate$(O) inftrees$(O) \
+	 zutil$(O)
+
+# libpng
+PNGSRCS=png$(C) pngerror$(C) pngget$(C) pngmem$(C) \
+	pngpread$(C) pngread$(C) pngrio$(C) pngrtran$(C) pngrutil$(C) \
+	pngset$(C) pngtrans$(C)
+
+# Standard headers
+PNGH   =png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h
+
+# Machine generated headers
+PNGCONF=pnglibconf.h
+
+# Headers callers use
+PNGINC= png.h pngconf.h pngusr.h $(PNGCONF)
+
+# Headers the PNG library uses
+PNGHDRS=$(PNGH) $(PNGCONF) pngusr.h
+
+PNGOBJS=png$(O) pngerror$(O) pngget$(O) pngmem$(O) \
+	pngpread$(O) pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) \
+	pngset$(O) pngtrans$(O)
+
+PROGSRCS= rpng2-x$(C) readpng2$(C)
+PROGHDRS= readpng2.h
+PROGDOCS= COPYING LICENSE
+PROGOBJS= rpng2-x$(O) readpng2$(O)
+
+OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+	$(CC) -c $(CFLAGS) $<
+
+# dependencies
+
+all: $(PROGDOCS) rpng2-x$(E)
+
+rpng2-x$(E): $(OBJS)
+	$(LD) -o rpng2-x$(E) $(OBJS) $(LIBS)
+
+# The DFA_XTRA setting turns all libpng options off then
+# turns on those required for this minimal build.
+# The CPP_FLAGS setting causes pngusr.h to be included in
+# both the build of pnglibconf.h and, subsequently, when
+# building libpng itself.
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+	$(PNGSRC)/scripts/pnglibconf.dfa \
+	$(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
+	$(RM) pnglibconf.h pnglibconf.dfn
+	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+	    DFA_XTRA="pngusr.dfa" $@
+
+clean:
+	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+	    srcdir=$(PNGSRC) clean
+	$(RM) rpng2-x$(O)
+	$(RM) rpng2-x$(E)
+	$(RM) $(OBJS)
+
+# distclean also removes the copied source and headers
+distclean: clean
+	$(RM) -r scripts # historical reasons
+	$(RM) $(PNGSRCS) $(PNGH)
+	$(RM) $(ZSRCS) $(ZH) $(ZCONF)
+	$(RM) $(PROGSRCS) $(PROGHDRS) $(PROGDOCS)
+
+# Header file dependencies:
+$(PROGOBJS): $(PROGHDRS) $(PNGINC) $(ZINC)
+$(PNGOBJS): $(PNGHDRS) $(ZINC)
+$(ZOBJS): $(ZHDRS)
+
+# Gather the source code from the respective directories
+$(PNGSRCS) $(PNGH): $(PNGSRC)/$@
+	$(RM) $@
+	$(COPY) $(PNGSRC)/$@ $@
+
+# No dependency on the ZLIBSRC target so that it only needs
+# to be specified once.
+$(ZSRCS) $(ZH):
+	$(RM) $@
+	$(COPY) $(ZLIBSRC)/$@ $@
+
+# The unconfigured zconf.h varies in name according to the
+# zlib release
+$(ZCONF):
+	$(RM) $@
+	@for f in zconf.h.in zconf.in.h zconf.h; do\
+	    test -r $(ZLIBSRC)/$$f &&\
+	    echo $(COPY) $(ZLIBSRC)/$$f $@ &&\
+	    $(COPY) $(ZLIBSRC)/$$f $@ && exit 0;\
+	done; echo copy: $(ZLIBSRC)/zconf.h not found; exit 1
+
+$(PROGSRCS) $(PROGHDRS) $(PROGDOCS): $(PROGSRC)/$@
+	$(RM) $@
+	$(COPY) $(PROGSRC)/$@ $@
+
+# End of makefile for rpng2-x

contrib/pngminim/preader/pngusr.dfa

@@ -0,0 +1,40 @@
+# pngminim/preader/pngusr.dfa
+#
+# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+# First all the build options off:
+
+everything = off
+
+# Just switch on the progressive read code
+
+option PROGRESSIVE_READ on
+
+# You may choose fixed or floating point APIs:
+# option FLOATING_POINT on
+
+option FIXED_POINT on
+
+# You must chose the internal fixed point implementation or to
+# use the system floating point.  The latter is considerably
+# smaller (by about 1kbyte on an x86 system):
+
+option FLOATING_ARITHMETIC on
+# option FLOATING_ARITHMETIC off
+
+# Your program will probably need other options.  The example
+# program here, rpng2-x, requires the following.  Take a look
+# at pnglibconf.h to find out the full set of what has to be
+# enabled to make the following work.
+
+option SETJMP on
+option STDIO on
+option READ_bKGD on
+option READ_GAMMA on
+option READ_EXPAND on
+option READ_STRIP_16_TO_8 on
+option READ_GRAY_TO_RGB on

contrib/pngminim/preader/pngusr.h

@@ -0,0 +1,24 @@
+/* minrdpngconf.h: headers to make a minimal png-read-only library
+ *
+ * Copyright (c) 2009, 2010-2011 Glenn Randers-Pehrson
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Derived from pngcrush.h, Copyright 1998-2007, Glenn Randers-Pehrson
+ */
+
+#ifndef MINPRDPNGCONF_H
+#define MINPRDPNGCONF_H
+
+/* To include pngusr.h set -DPNG_USER_CONFIG in CPPFLAGS */
+
+/* List options to turn off features of the build that do not
+ * affect the API (so are not recorded in pnglibconf.h)
+ */
+
+#define PNG_NO_WARNINGS
+#define PNG_ALIGN_TYPE PNG_ALIGN_NONE
+
+#endif /* MINPRDPNGCONF_H */

contrib/pngminus/README

@@ -20,7 +20,7 @@ Soon after the creation of PNG in 1995, the need was felt for a set of
 pnmtopng / pngtopnm utilities. Independantly Alexander Lehmann and I
 (Willem van Schaik) started such a project. Luckily we discovered this
 and merged the two together into pnmtopng.tar.gz, which is available
-from a/o ftp://swrinde.nde.swri.edu/pub/png/.
+from a/o ftp://ftp.simplesystems.org/pub/libpng/png/.
 
 These two utilities have many, many options and make use of most of the
 features of PNG, like gamma, alpha, sbit, text-chunks, etc. This makes

contrib/pngminus/makefile.std

@@ -8,9 +8,9 @@ LD=$(CC)
 RM=rm -f
 
 #PNGPATH = /usr/local
-#PNGINC = -I$(PNGPATH)/include/libpng12
-#PNGLIB = -L$(PNGPATH)/lib -lpng12
-#PNGLIBS = $(PNGPATH)/lib/libpng12.a
+#PNGINC = -I$(PNGPATH)/include/libpng17
+#PNGLIB = -L$(PNGPATH)/lib -lpng17
+#PNGLIBS = $(PNGPATH)/lib/libpng17.a
 PNGINC = -I../..
 PNGLIB = -L../.. -lpng
 PNGLIBS = ../../libpng.a
@@ -23,9 +23,9 @@ ZINC = -I../../../zlib
 ZLIB = -L../../../zlib -lz
 ZLIBS = ../../../zlib/libz.a
 
-CFLAGS=-O3 $(PNGINC) $(ZINC)
-LDFLAGS=$(PNGLIB) $(ZLIB)
-LDFLAGSS=$(PNGLIBS) $(ZLIBS)
+CFLAGS=$(PNGINC) $(ZINC)
+LDLIBS=$(PNGLIB) $(ZLIB)
+LDLIBSS=$(PNGLIBS) $(ZLIBS)
 C=.c
 O=.o
 L=.a
@@ -40,19 +40,19 @@ png2pnm$(O): png2pnm$(C)
 	$(CC) -c $(CFLAGS) png2pnm$(C)
 
 png2pnm$(E): png2pnm$(O)
-	$(LD) -o png2pnm$(E) png2pnm$(O) $(LDFLAGS) -lm
+	$(LD) $(LDFLAGS) -o png2pnm$(E) png2pnm$(O) $(LDLIBS) -lm
 
 png2pnm-static$(E): png2pnm$(O)
-	$(LD) -o png2pnm-static$(E) png2pnm$(O) $(LDFLAGSS) -lm
+	$(LD) $(LDFLAGS) -o png2pnm-static$(E) png2pnm$(O) $(LDLIBSS) -lm
 
 pnm2png$(O): pnm2png$(C)
 	$(CC) -c $(CFLAGS) pnm2png$(C)
 
 pnm2png$(E): pnm2png$(O)
-	$(LD) -o pnm2png$(E) pnm2png$(O) $(LDFLAGS) -lm
+	$(LD) $(LDFLAGS) -o pnm2png$(E) pnm2png$(O) $(LDLIBS) -lm
 
 pnm2png-static$(E): pnm2png$(O)
-	$(LD) -o pnm2png-static$(E) pnm2png$(O) $(LDFLAGSS) -lm
+	$(LD) $(LDFLAGS) -o pnm2png-static$(E) pnm2png$(O) $(LDLIBSS) -lm
 
 clean:
 	$(RM) png2pnm$(O)

contrib/pngminus/png2pnm.c

@@ -18,6 +18,7 @@
 #include <mem.h>
 #include <fcntl.h>
 #endif
+#include <zlib.h>
 
 #ifndef BOOL
 #define BOOL unsigned char
@@ -144,7 +145,7 @@ int main(int argc, char *argv[])
   if (png2pnm (fp_rd, fp_wr, fp_al, raw, alpha) == FALSE)
   {
     fprintf (stderr, "PNG2PNM\n");
-    fprintf (stderr, "Error:  unsuccessful convertion of PNG-image\n");
+    fprintf (stderr, "Error:  unsuccessful conversion of PNG-image\n");
     exit(1);
   }
 
@@ -211,8 +212,8 @@ BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL a
   if (ret != 8)
     return FALSE;
 
-  ret = png_check_sig (buf, 8);
-  if (!ret)
+  ret = png_sig_cmp (buf, 0, 8);
+  if (ret)
     return FALSE;
 
   /* create png and info structures */

contrib/pngminus/png2pnm.sh

@@ -1,3 +1,4 @@
+#!/bin/sh
 # -- grayscale
 ./png2pnm -noraw ../pngsuite/basn0g01.png basn0g01.pgm
 ./png2pnm -noraw ../pngsuite/basn0g02.png basn0g02.pgm

contrib/pngminus/pngminus.sh

@@ -1,3 +1,4 @@
+#!/bin/sh
 make -f makefile.std
 sh png2pnm.sh
 sh pnm2png.sh

contrib/pngminus/pnm2png.c

@@ -18,6 +18,7 @@
 #include <mem.h>
 #include <fcntl.h>
 #endif
+#include <zlib.h>
 
 #ifndef BOOL
 #define BOOL unsigned char
@@ -197,6 +198,9 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
   char          height_token[16];
   char          maxval_token[16];
   int           color_type;
+  unsigned long   ul_width, ul_alpha_width;
+  unsigned long   ul_height, ul_alpha_height;
+  unsigned long   ul_maxval;
   png_uint_32   width, alpha_width;
   png_uint_32   height, alpha_height;
   png_uint_32   maxval;
@@ -227,11 +231,15 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
     raw = (type_token[1] == '5');
     color_type = PNG_COLOR_TYPE_GRAY;
     get_token(pnm_file, width_token);
-    sscanf (width_token, "%lu", &width);
+    sscanf (width_token, "%lu", &ul_width);
+    width = (png_uint_32) ul_width;
     get_token(pnm_file, height_token);
-    sscanf (height_token, "%lu", &height);
+    sscanf (height_token, "%lu", &ul_height);
+    height = (png_uint_32) ul_height;
     get_token(pnm_file, maxval_token);
-    sscanf (maxval_token, "%lu", &maxval);
+    sscanf (maxval_token, "%lu", &ul_maxval);
+    maxval = (png_uint_32) ul_maxval;
+
     if (maxval <= 1)
       bit_depth = 1;
     else if (maxval <= 3)
@@ -248,11 +256,14 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
     raw = (type_token[1] == '6');
     color_type = PNG_COLOR_TYPE_RGB;
     get_token(pnm_file, width_token);
-    sscanf (width_token, "%lu", &width);
+    sscanf (width_token, "%lu", &ul_width);
+    width = (png_uint_32) ul_width;
     get_token(pnm_file, height_token);
-    sscanf (height_token, "%lu", &height);
+    sscanf (height_token, "%lu", &ul_height);
+    height = (png_uint_32) ul_height;
     get_token(pnm_file, maxval_token);
-    sscanf (maxval_token, "%lu", &maxval);
+    sscanf (maxval_token, "%lu", &ul_maxval);
+    maxval = (png_uint_32) ul_maxval;
     if (maxval <= 1)
       bit_depth = 1;
     else if (maxval <= 3)
@@ -287,15 +298,18 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
     {
       alpha_raw = (type_token[1] == '5');
       get_token(alpha_file, width_token);
-      sscanf (width_token, "%lu", &alpha_width);
+      sscanf (width_token, "%lu", &ul_alpha_width);
+      alpha_width=(png_uint_32) ul_alpha_width;
       if (alpha_width != width)
         return FALSE;
       get_token(alpha_file, height_token);
-      sscanf (height_token, "%lu", &alpha_height);
+      sscanf (height_token, "%lu", &ul_alpha_height);
+      alpha_height = (png_uint_32) ul_alpha_height;
       if (alpha_height != height)
         return FALSE;
       get_token(alpha_file, maxval_token);
-      sscanf (maxval_token, "%lu", &maxval);
+      sscanf (maxval_token, "%lu", &ul_maxval);
+      maxval = (png_uint_32) ul_maxval;
       if (maxval <= 1)
         alpha_depth = 1;
       else if (maxval <= 3)
@@ -510,6 +524,7 @@ png_uint_32 get_value (FILE *pnm_file, int depth)
 {
   static png_uint_32 mask = 0;
   png_byte token[16];
+  unsigned long ul_ret_value;
   png_uint_32 ret_value;
   int i = 0;
 
@@ -518,7 +533,8 @@ png_uint_32 get_value (FILE *pnm_file, int depth)
       mask = (mask << 1) | 0x01;
 
   get_token (pnm_file, (char *) token);
-  sscanf ((const char *) token, "%lu", &ret_value);
+  sscanf ((const char *) token, "%lu", &ul_ret_value);
+  ret_value = (png_uint_32) ul_ret_value;
 
   ret_value &= mask;
 

contrib/pngminus/pnm2png.sh

@@ -1,3 +1,4 @@
+#!/bin/sh
 # -- grayscale
 ./pnm2png basn0g01.pgm basn0g01.png
 ./pnm2png basn0g02.pgm basn0g02.png

contrib/pngsuite/README

@@ -1,17 +1,21 @@
 
 pngsuite
 --------
-(c) Willem van Schaik, 1999
+(c) Willem van Schaik, 1999, 2011, 2012
+Two images are by Glenn Randers-Pehrson, 2012
 
-Permission to use, copy, and distribute these images for any purpose and
-without fee is hereby granted.
+Permission to use, copy, modify, and distribute these images for any
+purpose and without fee is hereby granted.
 
-These 15 images are part of the much larger PngSuite test-set of 
+The 15 "bas*.png" images are part of the much larger PngSuite test-set of
 images, available for developers of PNG supporting software. The
 complete set, available at http:/www.schaik.com/pngsuite/, contains
 a variety of images to test interlacing, gamma settings, ancillary
 chunks, etc.
 
+The "ft*.png" images are "free/libre" replacements for the transparent
+corresponding t*.png images in the PngSuite.
+
 The images in this directory represent the basic PNG color-types:
 grayscale (1-16 bit deep), full color (8 or 16 bit), paletted
 (1-8 bit) and grayscale or color images with alpha channel. You
@@ -35,7 +39,23 @@ can use them to test the proper functioning of PNG software.
     basn6a08.png   8-bit RGBA
     basn6a16.png  16-bit RGBA
 
-Here is the correct result of typing "pngtest -m *.png" in
+    ftbbn0g01.png  1-bit grayscale, black bKGD
+    ftbbn0g02.png  2-bit grayscale, black bKGD
+    ftbbn0g04.png  4-bit grayscale, black bKGD
+    ftbbn2c16.png 16-bit truecolor, black bKGD
+    ftbbn3p08.png  8-bit paletted, black bKGD
+    ftbgn2c16.png 16-bit truecolor, gray bKGD
+    ftbgn3p08.png  8-bit paletted, gray bKGD
+    ftbrn2c08.png  8-bit truecolor, red bKGD
+    ftbwn0g16.png 16-bit gray, white bKGD
+    ftbwn3p08.png  8-bit paletted, white bKGD
+    ftbyn3p08.png  8-bit paletted, yellow bKGD
+    ftp0n0g08.png  8-bit grayscale, opaque
+    ftp0n2c08.png  8-bit truecolor, opaque
+    ftp0n3p08.png  8-bit paletted, opaque
+    ftp1n3p08.png  8-bit paletted, no bKGD
+
+Here is the correct result of typing "pngtest -m bas*.png" in
 this directory:
 
 Testing basn0g01.png: PASS (524 zero samples)

contrib/tools/README.txt

@@ -0,0 +1,26 @@
+This directory (contrib/tools) contains tools used by the authors of libpng.
+
+Code and data placed in this directory is not required to build libpng,
+however the code in this directory has been used to generate data or code in
+the body of the libpng source.  The source code identifies where this has
+been done.  Code in this directory may not compile on all operating systems
+that libpng supports.
+
+NO COPYRIGHT RIGHTS ARE CLAIMED TO ANY OF THE FILES IN THIS DIRECTORY.
+
+To the extent possible under law, the authors have waived all copyright and
+related or neighboring rights to this work.  This work is published from:
+United States.
+
+The files may be used freely in any way.
+
+The source code and comments in this directory are the original work of the
+people named below.  No other person or organization has made contributions to
+the work in this directory.
+
+ORIGINAL AUTHORS
+    The following people have contributed to the code in this directory.  None
+    of the people below claim any rights with regard to the contents of this
+    directory.
+
+    John Bowler <jbowler@acm.org>

contrib/tools/checksum-icc.c

@@ -0,0 +1,102 @@
+/* checksum-icc.c
+ *
+ * Copyright (c) 2012 John Cunningham Bowler
+ *
+ * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Generate crc32 and adler32 checksums of the given input files, used to
+ * generate check-codes for use when matching ICC profiles within libpng.
+ */
+#include <stdio.h>
+
+#include <zlib.h>
+
+static int
+read_one_file(FILE *ip, const char *name)
+{
+   uLong length = 0;
+   uLong a32 = adler32(0, NULL, 0);
+   uLong c32 = crc32(0, NULL, 0);
+   Byte header[132];
+
+   for (;;)
+   {
+      int ch = getc(ip);
+      Byte b;
+
+      if (ch == EOF) break;
+
+      b = (Byte)ch;
+
+      if (length < sizeof header)
+         header[length] = b;
+
+      ++length;
+      a32 = adler32(a32, &b, 1);
+      c32 = crc32(c32, &b, 1);
+   }
+
+   if (ferror(ip))
+      return 0;
+
+   /* Success */
+   printf("PNG_ICC_CHECKSUM(0x%8.8lx, 0x%8.8lx,\n   PNG_MD5("
+      "0x%2.2x%2.2x%2.2x%2.2x, 0x%2.2x%2.2x%2.2x%2.2x, 0x%2.2x%2.2x%2.2x%2.2x,"
+      " 0x%2.2x%2.2x%2.2x%2.2x), %d,\n"
+      "   \"%4.4d/%2.2d/%2.2d %2.2d:%2.2d:%2.2d\", %lu, \"%s\")\n",
+      (unsigned long)a32, (unsigned long)c32,
+      header[84], header[85], header[86], header[87],
+      header[88], header[89], header[90], header[91],
+      header[92], header[93], header[94], header[95],
+      header[96], header[97], header[98], header[99],
+#     define u16(x) (header[x] * 256 + header[x+1])
+#     define u32(x) (u16(x) * 65536 + u16(x+2))
+      u32(64), u16(24), u16(26), u16(28), u16(30), u16(32), u16(34),
+      (unsigned long)length, name);
+
+   return 1;
+}
+
+int main(int argc, char **argv)
+{
+   int err = 0;
+
+   printf("/* adler32, crc32, MD5[16], intent, date, length, file-name */\n");
+
+   if (argc > 1)
+   {
+      int i;
+
+      for (i=1; i<argc; ++i)
+      {
+         FILE *ip = fopen(argv[i], "rb");
+
+         if (ip == NULL || !read_one_file(ip, argv[i]))
+         {
+            err = 1;
+            perror(argv[i]);
+            fprintf(stderr, "%s: read error\n", argv[i]);
+            printf("/* ERROR: %s */\n", argv[i]);
+         }
+
+         (void)fclose(ip);
+      }
+   }
+
+   else
+   {
+      if (!read_one_file(stdin, "-"))
+      {
+         err = 1;
+         perror("stdin");
+         fprintf(stderr, "stdin: read error\n");
+         printf("/* ERROR: stdin */\n");
+      }
+   }
+
+   return err;
+}

contrib/tools/chkfmt

@@ -0,0 +1,137 @@
+#!/bin/sh
+#
+# Check the format of the source files in the current directory - checks for a
+# line length of 80 characters max and no tab characters.
+#
+# Optionally arguments are files or directories to check.
+#
+# -v: output the long lines (makes fixing them easier)
+# -e: spawn an editor for each file that needs a change ($EDITOR must be
+#     defined).  When using -e the script MUST be run from an interactive
+#     command line.
+verbose=
+edit=
+vers=
+test "$1" = "-v" && {
+   shift
+   verbose=yes
+}
+test "$1" = "-e" && {
+   shift
+   if test -n "$EDITOR"
+   then
+      edit=yes
+
+      # Copy the standard streams for the editor
+      exec 3>&0 4>&1 5>&2
+   else
+      echo "chkfmt -e: EDITOR must be defined" >&2
+      exit 1
+   fi
+}
+
+# Function to edit a single file - if the file isn't changed ask the user
+# whether or not to continue.  This stuff only works if the script is run from
+# the command line (otherwise, don't specify -e or you will be sorry).
+doed(){
+   cp "$file" "$file".orig
+   "$EDITOR" "$file" 0>&3 1>&4 2>&5 3>&- 4>&- 5>&- || exit 1
+   if cmp -s "$file".orig "$file"
+   then
+      rm "$file".orig
+      echo -n "$file: file not changed, type anything to continue: " >&5
+      read ans 0>&3
+      test -n "$ans" || return 1
+   fi
+   return 0
+}
+
+# In beta versions the version string which appears in files can be a little
+# long and cause spuriously overlong lines.  To avoid this subtitute the version
+# string with a 'standard' version a.b.cc before checking for long lines.
+if test -r png.h
+then
+   vers="`sed -n -e \
+   's/^#define PNG_LIBPNG_VER_STRING .\([0-9]\.[0-9]\.[0-9][0-9a-z]*\).$/\1/p' \
+   png.h`"
+   echo "chkfmt: checking version $vers"
+fi
+if test -z "$vers"
+then
+   echo "chkfmt: png.h not found, ignoring version number" >&2
+fi
+
+test -n "$1" || set -- .
+find "$@" \( -type d \( -name '.git' -o -name '.libs' -o -name 'projects' \) \
+   -prune \) -o \( -type f \
+   ! -name '*.[oa]' ! -name '*.l[oa]' !  -name '*.png' ! -name '*.out' \
+   ! -name '*.jpg' ! -name '*.patch' ! -name '*.obj' ! -name '*.exe' \
+   ! -name '*.com' ! -name '*.tar.*' ! -name '*.zip' ! -name '*.ico' \
+   ! -name '*.res' ! -name '*.rc' ! -name '*.mms' ! -name '*.rej' \
+   ! -name '*.dsp' ! -name '*.orig' ! -name '*.dfn' ! -name '*.swp' \
+   ! -name '~*' ! -name '*.3' \
+   ! -name 'missing' ! -name 'mkinstalldirs' ! -name 'depcomp' \
+   ! -name 'aclocal.m4' ! -name 'install-sh' ! -name 'Makefile.in' \
+   ! -name 'ltmain.sh' ! -name 'config*' -print \) | {
+   st=0
+   while read file
+   do
+      case "$file" in
+      *.mak|*[Mm]akefile.*|*[Mm]akefile)
+         # Makefiles require tabs, dependency lines can be this long.
+         check_tabs=
+         line_length=100;;
+      *.awk)
+         # Includes literal tabs
+         check_tabs=
+         # The following is arbitrary
+         line_length=132;;
+      *contrib/*/*.[ch])
+         check_tabs=yes
+         line_length=96;;
+      *)
+         check_tabs=yes
+         line_length=80;;
+      esac
+
+      # Note that vers can only contain 0-9, . and a-z
+      if test -n "$vers"
+      then
+         sed -e "s/$vers/a.b.cc/g" "$file" >"$file".$$
+      else
+         cp "$file" "$file".$$
+      fi
+      splt="`fold -$line_length "$file".$$ | diff -c "$file".$$ -`"
+      rm "$file".$$
+
+      if test -n "$splt"
+      then
+         echo "$file: lines too long"
+         st=1
+         if test -n "$EDITOR" -a -n "$edit"
+         then
+            doed "$file" || exit 1
+         elif test -n "$verbose"
+         then
+            echo "$splt"
+         fi
+      fi
+      if test -n "$check_tabs"
+      then
+         tab="`tr -c -d '\t' <"$file"`"
+         if test -n "$tab"
+         then
+            echo "$file: file contains tab characters"
+            st=1
+            if test -n "$EDITOR" -a -n "$edit"
+            then
+               doed "$file" || exit 1
+            elif test -n "$verbose"
+            then
+               echo "$splt"
+            fi
+         fi
+      fi
+   done
+   exit $st
+}

contrib/tools/cvtcolor.c

@@ -0,0 +1,188 @@
+/*-
+ * convert.c
+ *
+ * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2012.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work.  This work is published from:
+ * United States.
+ *
+ * Convert 8-bit sRGB or 16-bit linear values to another format.
+ */
+#define _ISOC99_SOURCE 1
+
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <stdio.h>
+
+#include <fenv.h>
+
+#include "sRGB.h"
+
+static void
+usage(const char *prog)
+{
+   fprintf(stderr,
+      "%s: usage: %s [-linear|-sRGB] [-gray|-color] component{1,4}\n",
+      prog, prog);
+   exit(1);
+}
+
+unsigned long
+component(const char *prog, const char *arg, int issRGB)
+{
+   char *ep;
+   unsigned long c = strtoul(arg, &ep, 0);
+
+   if (ep <= arg || *ep || c > 65535 || (issRGB && c > 255))
+   {
+      fprintf(stderr, "%s: %s: invalid component value (%lu)\n", prog, arg, c);
+      usage(prog);
+   }
+
+   return c;
+}
+
+int
+main(int argc, const char **argv)
+{
+   const char *prog = *argv++;
+   int to_linear = 0, to_gray = 0, to_color = 0;
+   int channels = 0;
+   double c[4];
+
+   /* FE_TONEAREST is the IEEE754 round to nearest, preferring even, mode; i.e.
+    * everything rounds to the nearest value except that '.5' rounds to the
+    * nearest even value.
+    */
+   fesetround(FE_TONEAREST);
+
+   c[3] = c[2] = c[1] = c[0] = 0;
+
+   while (--argc > 0 && **argv == '-')
+   {
+      const char *arg = 1+*argv++;
+
+      if (strcmp(arg, "sRGB") == 0)
+         to_linear = 0;
+
+      else if (strcmp(arg, "linear") == 0)
+         to_linear = 1;
+
+      else if (strcmp(arg, "gray") == 0)
+         to_gray = 1, to_color = 0;
+
+      else if (strcmp(arg, "color") == 0)
+         to_gray = 0, to_color = 1;
+
+      else
+         usage(prog);
+   }
+
+   switch (argc)
+   {
+      default:
+         usage(prog);
+         break;
+
+      case 4:
+         c[3] = component(prog, argv[3], to_linear);
+         ++channels;
+      case 3:
+         c[2] = component(prog, argv[2], to_linear);
+         ++channels;
+      case 2:
+         c[1] = component(prog, argv[1], to_linear);
+         ++channels;
+      case 1:
+         c[0] = component(prog, argv[0], to_linear);
+         ++channels;
+         break;
+      }
+
+   if (to_linear)
+   {
+      int i;
+      int components = channels;
+
+      if ((components & 1) == 0)
+         --components;
+
+      for (i=0; i<components; ++i) c[i] = linear_from_sRGB(c[i] / 255);
+      if (components < channels)
+         c[components] = c[components] / 255;
+   }
+
+   else
+   {
+      int i;
+      for (i=0; i<4; ++i) c[i] /= 65535;
+
+      if ((channels & 1) == 0)
+      {
+         double alpha = c[channels-1];
+
+         if (alpha > 0)
+            for (i=0; i<channels-1; ++i) c[i] /= alpha;
+         else
+            for (i=0; i<channels-1; ++i) c[i] = 1;
+      }
+   }
+
+   if (to_gray)
+   {
+      if (channels < 3)
+      {
+         fprintf(stderr, "%s: too few channels (%d) for -gray\n",
+            prog, channels);
+         usage(prog);
+      }
+
+      c[0] = YfromRGB(c[0], c[1], c[2]);
+      channels -= 2;
+   }
+
+   if (to_color)
+   {
+      if (channels > 2)
+      {
+         fprintf(stderr, "%s: too many channels (%d) for -color\n",
+            prog, channels);
+         usage(prog);
+      }
+
+      c[3] = c[1]; /* alpha, if present */
+      c[2] = c[1] = c[0];
+   }
+
+   if (to_linear)
+   {
+      int i;
+      if ((channels & 1) == 0)
+      {
+         double alpha = c[channels-1];
+         for (i=0; i<channels-1; ++i) c[i] *= alpha;
+      }
+
+      for (i=0; i<channels; ++i) c[i] = nearbyint(c[i] * 65535);
+   }
+
+   else /* to sRGB */
+   {
+      int i = (channels+1)&~1;
+      while (--i >= 0)
+         c[i] = sRGB_from_linear(c[i]);
+
+      for (i=0; i<channels; ++i) c[i] = nearbyint(c[i] * 255);
+   }
+
+   {
+      int i;
+      for (i=0; i<channels; ++i) printf(" %g", c[i]);
+   }
+   printf("\n");
+
+   return 0;
+}

contrib/tools/intgamma.sh

@@ -0,0 +1,110 @@
+#!/bin/sh
+#
+# intgamma.sh
+#
+# Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+#
+# COPYRIGHT: Written by John Cunningham Bowler, 2012.
+# To the extent possible under law, the author has waived all copyright and
+# related or neighboring rights to this work.  This work is published from:
+# United States.
+#
+# Shell script to generate png.c 8-bit and 16-bit log tables (see the code in
+# png.c for details).
+#
+# This script uses the "bc" arbitrary precision calculator to calculate 32-bit
+# fixed point values of logarithms appropriate to finding the log of an 8-bit
+# (0..255) value and a similar table for the exponent calculation.
+#
+# "bc" must be on the path when the script is executed, and the math library
+# (-lm) must be available
+#
+# function to print out a list of numbers as integers; the function truncates
+# the integers which must be one-per-line
+function print(){
+   awk 'BEGIN{
+      str = ""
+   }
+   {
+      sub("\\.[0-9]*$", "")
+      if ($0 == "")
+         $0 = "0"
+
+      if (str == "")
+         t = "   " $0 "U"
+      else
+         t = str ", " $0 "U"
+
+      if (length(t) >= 80) {
+         print str ","
+         str = "   " $0 "U"
+      } else
+         str = t
+   }
+   END{
+      print str
+   }'
+}
+#
+# The logarithm table.
+cat <<END
+/* 8-bit log table: png_8bit_l2[128]
+ * This is a table of -log(value/255)/log(2) for 'value' in the range 128 to
+ * 255, so it's the base 2 logarithm of a normalized 8-bit floating point
+ * mantissa.  The numbers are 32-bit fractions.
+ */
+static const png_uint_32
+png_8bit_l2[128] =
+{
+END
+#
+bc -lqws <<END | print
+f=65536*65536/l(2)
+for (i=128;i<256;++i) { .5 - l(i/255)*f; }
+END
+echo '};'
+echo
+#
+# The exponent table.
+cat <<END
+/* The 'exp()' case must invert the above, taking a 20-bit fixed point
+ * logarithmic value and returning a 16 or 8-bit number as appropriate.  In
+ * each case only the low 16 bits are relevant - the fraction - since the
+ * integer bits (the top 4) simply determine a shift.
+ *
+ * The worst case is the 16-bit distinction between 65535 and 65534; this
+ * requires perhaps spurious accuracy in the decoding of the logarithm to
+ * distinguish log2(65535/65534.5) - 10^-5 or 17 bits.  There is little chance
+ * of getting this accuracy in practice.
+ *
+ * To deal with this the following exp() function works out the exponent of the
+ * frational part of the logarithm by using an accurate 32-bit value from the
+ * top four fractional bits then multiplying in the remaining bits.
+ */
+static const png_uint_32
+png_32bit_exp[16] =
+{
+END
+#
+bc -lqws <<END | print
+f=l(2)/16
+for (i=0;i<16;++i) {
+   x = .5 + e(-i*f)*2^32;
+   if (x >= 2^32) x = 2^32-1;
+   x;
+}
+END
+echo '};'
+echo
+#
+# And the table of adjustment values.
+cat <<END
+/* Adjustment table; provided to explain the numbers in the code below. */
+#if 0
+END
+bc -lqws <<END | awk '{ printf "%5d %s\n", 12-NR, $0 }'
+for (i=11;i>=0;--i){
+   (1 - e(-(2^i)/65536*l(2))) * 2^(32-i)
+}
+END
+echo '#endif'

contrib/tools/makesRGB.c

@@ -0,0 +1,430 @@
+/* makesRGB.c -- build sRGB-to-linear and linear-to-sRGB conversion tables
+ *
+ * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2012.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work.  This work is published from:
+ * United States.
+ *
+ * Make a table to convert 8-bit sRGB encoding values into the closest 16-bit
+ * linear value.
+ *
+ * Make two tables to take a linear value scaled to 255*65535 and return an
+ * approximation to the 8-bit sRGB encoded value.  Calculate the error in these
+ * tables and display it.
+ */
+#define _C99_SOURCE 1
+#include <stdio.h>
+#include <math.h>
+#include <stdlib.h>
+
+/* pngpriv.h includes the definition of 'PNG_sRGB_FROM_LINEAR' which is required
+ * to verify the actual code.
+ */
+#include "../../pngpriv.h"
+
+#include "sRGB.h"
+
+/* The tables are declared 'const' in pngpriv.h, so this redefines the tables to
+ * be used.
+ */
+#define png_sRGB_table sRGB_table
+#define png_sRGB_base sRGB_base
+#define png_sRGB_delta sRGB_delta
+
+static png_uint_16 png_sRGB_table[256];
+static png_uint_16 png_sRGB_base[512];
+static png_byte png_sRGB_delta[512];
+
+static const unsigned int max_input = 255*65535;
+
+double
+fsRGB(double l)
+{
+   return sRGB_from_linear(l/max_input);
+}
+
+double
+sRGB(unsigned int i)
+{
+   return fsRGB(i);
+}
+
+double
+finvsRGB(unsigned int i)
+{
+   return 65535 * linear_from_sRGB(i/255.);
+}
+
+png_uint_16
+invsRGB(unsigned int i)
+{
+   unsigned int x = nearbyint(finvsRGB(i));
+
+   if (x > 65535)
+   {
+      fprintf(stderr, "invsRGB(%u) overflows to %u\n", i, x);
+      exit(1);
+   }
+
+   return (png_uint_16)x;
+}
+
+int
+main(int argc, char **argv)
+{
+   unsigned int i, i16, ibase;
+   double min_error = 0;
+   double max_error = 0;
+   double min_error16 = 0;
+   double max_error16 = 0;
+   double adjust;
+   double adjust_lo = 0.4, adjust_hi = 0.6, adjust_mid = 0.5;
+   unsigned int ec_lo = 0, ec_hi = 0, ec_mid = 0;
+   unsigned int error_count = 0;
+   unsigned int error_count16 = 0;
+   int test_only = 0;
+
+   if (argc > 1)
+      test_only = strcmp("--test", argv[1]) == 0;
+
+   /* Initialize the encoding table first. */
+   for (i=0; i<256; ++i)
+   {
+      png_sRGB_table[i] = invsRGB(i);
+   }
+
+   /* Now work out the decoding tables (this is where the error comes in because
+    * there are 512 set points and 512 straight lines between them.)
+    */
+   for (;;)
+   {
+      if (ec_lo == 0)
+         adjust = adjust_lo;
+
+      else if (ec_hi == 0)
+         adjust = adjust_hi;
+
+      else if (ec_mid == 0)
+         adjust = adjust_mid;
+
+      else if (ec_mid < ec_hi)
+         adjust = (adjust_mid + adjust_hi)/2;
+
+      else if (ec_mid < ec_lo)
+         adjust = (adjust_mid + adjust_lo)/2;
+
+      else
+      {
+         fprintf(stderr, "not reached: %u .. %u .. %u\n", ec_lo, ec_mid, ec_hi);
+         exit(1);
+      }
+
+      /* Calculate the table using the current 'adjust' */
+      for (i=0; i<=511; ++i)
+      {
+         double lo = 255 * sRGB(i << 15);
+         double hi = 255 * sRGB((i+1) << 15);
+         unsigned int calc;
+
+         calc = nearbyint((lo+adjust) * 256);
+         if (calc > 65535)
+         {
+            fprintf(stderr, "table[%d][0]: overflow %08x (%d)\n", i, calc,
+               calc);
+            exit(1);
+         }
+         png_sRGB_base[i] = calc;
+
+         calc = nearbyint((hi-lo) * 32);
+         if (calc > 255)
+         {
+            fprintf(stderr, "table[%d][1]: overflow %08x (%d)\n", i, calc,
+               calc);
+            exit(1);
+         }
+         png_sRGB_delta[i] = calc;
+      }
+
+      /* Check the 16-bit linear values alone: */
+      error_count16 = 0;
+      for (i16=0; i16 <= 65535; ++i16)
+      {
+         unsigned int i = 255*i16;
+         unsigned int iexact = nearbyint(255*sRGB(i));
+         unsigned int icalc = PNG_sRGB_FROM_LINEAR(i);
+
+         if (icalc != iexact)
+            ++error_count16;
+      }
+
+      /* Now try changing the adjustment. */
+      if (ec_lo == 0)
+         ec_lo = error_count16;
+
+      else if (ec_hi == 0)
+         ec_hi = error_count16;
+
+      else if (ec_mid == 0)
+      {
+         ec_mid = error_count16;
+         printf("/* initial error counts: %u .. %u .. %u */\n", ec_lo, ec_mid,
+            ec_hi);
+      }
+
+      else if (error_count16 < ec_mid)
+      {
+         printf("/* adjust (mid ): %f: %u -> %u */\n", adjust, ec_mid,
+            error_count16);
+         ec_mid = error_count16;
+         adjust_mid = adjust;
+      }
+
+      else if (adjust < adjust_mid && error_count16 < ec_lo)
+      {
+         printf("/* adjust (low ): %f: %u -> %u */\n", adjust, ec_lo,
+            error_count16);
+         ec_lo = error_count16;
+         adjust_lo = adjust;
+      }
+
+      else if (adjust > adjust_mid && error_count16 < ec_hi)
+      {
+         printf("/* adjust (high): %f: %u -> %u */\n", adjust, ec_hi,
+            error_count16);
+         ec_hi = error_count16;
+         adjust_hi = adjust;
+      }
+
+      else
+      {
+         adjust = adjust_mid;
+         printf("/* adjust: %f: %u */\n", adjust, ec_mid);
+         break;
+      }
+   }
+
+   /* For each entry in the table try to adjust it to minimize the error count
+    * in that entry.  Each entry corresponds to 128 input values.
+    */
+   for (ibase=0; ibase<65536; ibase+=128)
+   {
+      png_uint_16 base = png_sRGB_base[ibase >> 7], trybase = base, ob=base;
+      png_byte delta = png_sRGB_delta[ibase >> 7], trydelta = delta, od=delta;
+      unsigned int ecbase = 0, eco;
+
+      for (;;)
+      {
+         png_sRGB_base[ibase >> 7] = trybase;
+         png_sRGB_delta[ibase >> 7] = trydelta;
+
+         /* Check the 16-bit linear values alone: */
+         error_count16 = 0;
+         for (i16=ibase; i16 < ibase+128; ++i16)
+         {
+            unsigned int i = 255*i16;
+            unsigned int iexact = nearbyint(255*sRGB(i));
+            unsigned int icalc = PNG_sRGB_FROM_LINEAR(i);
+
+            if (icalc != iexact)
+               ++error_count16;
+         }
+
+         if (error_count16 == 0)
+            break;
+
+         if (ecbase == 0)
+         {
+            eco = ecbase = error_count16;
+            ++trybase; /* First test */
+         }
+
+         else if (error_count16 < ecbase)
+         {
+            if (trybase > base)
+            {
+               base = trybase;
+               ++trybase;
+            }
+            else if (trybase < base)
+            {
+               base = trybase;
+               --trybase;
+            }
+            else if (trydelta > delta)
+            {
+               delta = trydelta;
+               ++trydelta;
+            }
+            else if (trydelta < delta)
+            {
+               delta = trydelta;
+               --trydelta;
+            }
+            else
+            {
+               fprintf(stderr, "makesRGB: impossible\n");
+               exit(1);
+            }
+            ecbase = error_count16;
+         }
+
+         else
+         {
+            if (trybase > base)
+               trybase = base-1;
+            else if (trybase < base)
+            {
+               trybase = base;
+               ++trydelta;
+            }
+            else if (trydelta > delta)
+               trydelta = delta-1;
+            else if (trydelta < delta)
+               break; /* end of tests */
+         }
+      }
+
+      png_sRGB_base[ibase >> 7] = base;
+      png_sRGB_delta[ibase >> 7] = delta;
+      if (base != ob || delta != od)
+      {
+         printf("/* table[%u]={%u,%u} -> {%u,%u} %u -> %u errors */\n",
+            ibase>>7, ob, od, base, delta, eco, ecbase);
+      }
+      else if (0)
+         printf("/* table[%u]={%u,%u} %u errors */\n", ibase>>7, ob, od,
+            ecbase);
+   }
+
+   /* Only do the full (slow) test at the end: */
+   min_error = -.4999;
+   max_error = .4999;
+   error_count = 0;
+
+   for (i=0; i <= max_input; ++i)
+   {
+      unsigned int iexact = nearbyint(255*sRGB(i));
+      unsigned int icalc = PNG_sRGB_FROM_LINEAR(i);
+
+      if (icalc != iexact)
+      {
+         double err = 255*sRGB(i) - icalc;
+
+         if (err > (max_error+.001) || err < (min_error-.001))
+         {
+            printf(
+               "/* 0x%08x: exact: %3d, got: %3d [tables: %08x, %08x] (%f) */\n",
+               i, iexact, icalc, png_sRGB_base[i>>15],
+               png_sRGB_delta[i>>15], err);
+         }
+
+         ++error_count;
+         if (err > max_error)
+            max_error = err;
+         else if (err < min_error)
+            min_error = err;
+      }
+   }
+
+   /* Re-check the 16-bit cases too, including the warning if there is an error
+    * bigger than 1.
+    */
+   error_count16 = 0;
+   max_error16 = 0;
+   min_error16 = 0;
+   for (i16=0; i16 <= 65535; ++i16)
+   {
+      unsigned int i = 255*i16;
+      unsigned int iexact = nearbyint(255*sRGB(i));
+      unsigned int icalc = PNG_sRGB_FROM_LINEAR(i);
+
+      if (icalc != iexact)
+      {
+         double err = 255*sRGB(i) - icalc;
+
+         ++error_count16;
+         if (err > max_error16)
+            max_error16 = err;
+         else if (err < min_error16)
+            min_error16 = err;
+
+         if (abs(icalc - iexact) > 1)
+            printf(
+               "/* 0x%04x: exact: %3d, got: %3d [tables: %08x, %08x] (%f) */\n",
+               i16, iexact, icalc, png_sRGB_base[i>>15],
+               png_sRGB_delta[i>>15], err);
+      }
+   }
+
+   /* Check the round trip for each 8-bit sRGB value. */
+   for (i16=0; i16 <= 255; ++i16)
+   {
+      unsigned int i = 255 * png_sRGB_table[i16];
+      unsigned int iexact = nearbyint(255*sRGB(i));
+      unsigned int icalc = PNG_sRGB_FROM_LINEAR(i);
+
+      if (i16 != iexact)
+      {
+         fprintf(stderr, "8-bit rounding error: %d -> %d\n", i16, iexact);
+         exit(1);
+      }
+
+      if (icalc != i16)
+      {
+         double finv = finvsRGB(i16);
+
+         printf("/* 8-bit roundtrip error: %d -> %f -> %d(%f) */\n",
+            i16, finv, icalc, fsRGB(255*finv));
+      }
+   }
+
+
+   printf("/* error: %g - %g, %u (%g%%) of readings inexact */\n",
+      min_error, max_error, error_count, (100.*error_count)/max_input);
+   printf("/* 16-bit error: %g - %g, %u (%g%%) of readings inexact */\n",
+      min_error16, max_error16, error_count16, (100.*error_count16)/65535);
+
+   if (!test_only)
+   {
+      printf("PNG_CONST png_uint_16 png_sRGB_table[256] =\n{\n   ");
+      for (i=0; i<255; )
+      {
+         do
+         {
+            printf("%d,", png_sRGB_table[i++]);
+         }
+         while ((i & 0x7) != 0 && i<255);
+         if (i<255) printf("\n   ");
+      }
+      printf("%d\n};\n\n", png_sRGB_table[i]);
+
+
+      printf("PNG_CONST png_uint_16 png_sRGB_base[512] =\n{\n   ");
+      for (i=0; i<511; )
+      {
+         do
+         {
+            printf("%d,", png_sRGB_base[i++]);
+         }
+         while ((i & 0x7) != 0 && i<511);
+         if (i<511) printf("\n   ");
+      }
+      printf("%d\n};\n\n", png_sRGB_base[i]);
+
+      printf("PNG_CONST png_byte png_sRGB_delta[512] =\n{\n   ");
+      for (i=0; i<511; )
+      {
+         do
+         {
+            printf("%d,", png_sRGB_delta[i++]);
+         }
+         while ((i & 0xf) != 0 && i<511);
+         if (i<511) printf("\n   ");
+      }
+      printf("%d\n};\n\n", png_sRGB_delta[i]);
+   }
+
+   return 0;
+}

contrib/tools/sRGB.h

@@ -0,0 +1,48 @@
+/*-
+ * sRGB.h
+ *
+ * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2012.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work.  This work is published from:
+ * United States.
+ *
+ * Utility file; not actually a header, this contains definitions of sRGB
+ * calculation functions for inclusion in those test programs that need them.
+ *
+ * All routines take and return a floating point value in the range
+ * 0 to 1.0, doing a calculation according to the sRGB specification
+ * (in fact the source of the numbers is the wikipedia article at
+ * http://en.wikipedia.org/wiki/SRGB).
+ */
+static double
+sRGB_from_linear(double l)
+{
+   if (l <= 0.0031308)
+      l *= 12.92;
+
+   else
+      l = 1.055 * pow(l, 1/2.4) - 0.055;
+
+   return l;
+}
+
+static double
+linear_from_sRGB(double s)
+{
+   if (s <= 0.04045)
+      return s / 12.92;
+
+   else
+      return pow((s+0.055)/1.055, 2.4);
+}
+
+static double
+YfromRGB(double r, double g, double b)
+{
+   /* Use the sRGB (rounded) coefficients for Rlinear, Glinear, Blinear to get
+    * the CIE Y value (also linear).
+    */
+   return 0.2126 * r + 0.7152 * g + 0.0722 * b;
+}