[master] Imported from libpng-1.6.17.tar

[master] Imported from libpng-1.6.16.tar
[master] Imported from libpng-1.6.15.tar
2025-07-10 18:04:09 +02:00 · 2015-03-26 08:11:22 -05:00 · 2015-01-15 12:47:40 -05:00 · 2014-11-20 10:23:30 -06:00 · 2014-10-22 19:33:27 -05:00 · 2014-08-21 05:59:56 -05:00
315 changed files with 5912 additions and 18498 deletions
--- a/59
+++ b/59
@@ -1,4 +1,4 @@
-Libpng 1.6.34 - September 29, 2017
+Libpng 1.6.17 - March 26, 2015

 This is a public release of libpng, intended for use in production codes.

@@ -7,24 +7,61 @@ Files available for download:
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script

-   libpng-1.6.34.tar.xz (LZMA-compressed, recommended)
-   libpng-1.6.34.tar.gz
+   libpng-1.6.17.tar.xz (LZMA-compressed, recommended)
+   libpng-1.6.17.tar.gz

 Source files with CRLF line endings (for Windows), without the
 "configure" script

-   lpng1634.7z  (LZMA-compressed, recommended)
-   lpng1634.zip
+   lpng1617.7z  (LZMA-compressed, recommended)
+   lpng1617.zip

 Other information:

-   libpng-1.6.34-README.txt
-   libpng-1.6.34-LICENSE.txt
-   libpng-1.6.34-*.asc (armored detached GPG signatures)
+   libpng-1.6.17-README.txt
+   libpng-1.6.17-LICENSE.txt
+   libpng-1.6.17-*.asc (armored detached GPG signatures)

-Changes since the last public release (1.6.33):
-  Removed contrib/pngsuite/i*.png; some of these were incorrect and caused
-    test failures.
+Changes since the last public release (1.6.16):
+
+  Removed duplicate PNG_SAFE_LIMITS_SUPPORTED handling from pngconf.h
+  Corrected the width limit calculation in png_check_IHDR().
+  Removed user limits from pngfix. Also pass NULL pointers to
+    png_read_row to skip the unnecessary row de-interlace stuff.
+  Added testing of png_set_packing() to pngvalid.c
+  Regenerated configure scripts in the *.tar distributions with libtool-2.4.4
+  Implement previously untested cases of libpng transforms in pngvalid.c
+  Fixed byte order in 2-byte filler, in png_do_read_filler().
+  Made the check for out-of-range values in png_set_tRNS() detect
+    values that are exactly 2^bit_depth, and work on 16-bit platforms.
+  Merged some parts of libpng-1.6.17beta01 and libpng-1.7.0beta47.
+  Added #ifndef __COVERITY__ where needed in png.c, pngrutil.c and
+    pngset.c to avoid warnings about dead code.
+  Do not build png_product2() when it is unused.
+  Display user limits in the output from pngtest.
+  Eliminated the PNG_SAFE_LIMITS macro and restored the 1-million-column
+    and 1-million-row default limits in pnglibconf.dfa, that can be reset
+    by the user at build time or run time.  This provides a more robust
+    defense against DOS and as-yet undiscovered overflows.
+  Added PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED macro, on by default.
+  Allow user to call png_get_IHDR() with NULL arguments (Reuben Hawkins).
+  Rebuilt configure scripts with automake-1.15 and libtool-2.4.6
+  Moved png_set_filter() prototype into a PNG_WRITE_SUPPORTED block
+    of png.h.
+  Avoid runtime checks when converting integer to png_byte with
+    Visual Studio (Sergey Kosarevsky)
+  Removed some comments that the configure script did not handle
+    properly from scripts/pnglibconf.dfa and pnglibconf.h.prebuilt.
+  Free the unknown_chunks structure even when it contains no data.
+  Updated CMakeLists.txt to add OSX framework, change YES/NO to ON/OFF
+    for consistency, and remove some useless tests (Alexey Petruchik).
+  Remove pnglibconf.h, pnglibconf.c, pnglibconf.pre, pnglibconf.dfn,
+    and pnglibconf.out instead of pnglibconf.* in "make clean" (Cosmin).
+  Fixed simplified 8-bit-linear to sRGB alpha. The calculated alpha
+    value was wrong.  It's not clear if this affected the final stored
+    value; in the obvious code path the upper and lower 8-bits of the
+    alpha value were identical and the alpha was truncated to 8-bits
+    rather than dividing by 257 (John Bowler).

 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
--- a/931
+++ b/931
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,57 +1,28 @@
 # CMakeLists.txt

-# Copyright (C) 2007,2009-2017 Glenn Randers-Pehrson
-# Written by Christian Ehrlicher, 2007
-# Revised by Roger Lowman, 2009-2010
-# Revised by Clifford Yapp, 2011-2012
-# Revised by Roger Leigh, 2016
-# Revised by Andreas Franek, 2016
+# Copyright (C) 2007-2015 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 3.0.2)
-cmake_policy(VERSION 3.0.2)
-
-# Set MacOSX @rpath usage globally.
-if (POLICY CMP0020)
-  cmake_policy(SET CMP0020 NEW)
-endif(POLICY CMP0020)
-if (POLICY CMP0042)
-  cmake_policy(SET CMP0042 NEW)
-endif(POLICY CMP0042)
-# Use new variable expansion policy.
-if (POLICY CMP0053)
-  cmake_policy(SET CMP0053 NEW)
-endif(POLICY CMP0053)
-if (POLICY CMP0054)
-  cmake_policy(SET CMP0054 NEW)
-endif(POLICY CMP0054)
+cmake_minimum_required(VERSION 2.4.4)
+set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS true)

 set(CMAKE_CONFIGURATION_TYPES "Release;Debug;MinSizeRel;RelWithDebInfo")

-project(libpng ASM C)
+project(libpng C)
 enable_testing()

 set(PNGLIB_MAJOR 1)
 set(PNGLIB_MINOR 6)
-set(PNGLIB_RELEASE 34)
+set(PNGLIB_RELEASE 17)
 set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
 set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})

-include(GNUInstallDirs)
-
 # needed packages
-
-#Allow users to specify location of Zlib,
-# Useful if zlib is being built alongside this as a sub-project
-option(PNG_BUILD_ZLIB "Custom zlib Location, else find_package is used" OFF)
-
-IF(NOT PNG_BUILD_ZLIB)
-  find_package(ZLIB REQUIRED)
-  include_directories(${ZLIB_INCLUDE_DIR})
-ENDIF(NOT PNG_BUILD_ZLIB)
+find_package(ZLIB REQUIRED)
+include_directories(${ZLIB_INCLUDE_DIR})

 if(NOT WIN32)
  find_library(M_LIBRARY
@@ -76,391 +47,32 @@ option(PNG_FRAMEWORK "Build OS X framework" OFF)
 option(PNG_DEBUG     "Build with debug output" OFF)
 option(PNGARG        "Disable ANSI-C prototypes" OFF)

-option(PNG_HARDWARE_OPTIMIZATIONS "Enable Hardware Optimizations" ON)
-
-
-set(PNG_PREFIX "" CACHE STRING "Prefix to add to the API function names")
-set(DFA_XTRA "" CACHE FILEPATH "File containing extra configuration settings")
-
-if(PNG_HARDWARE_OPTIMIZATIONS)
-# set definitions and sources for arm
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^arm" OR
-  CMAKE_SYSTEM_PROCESSOR MATCHES "^aarch64")
-  set(PNG_ARM_NEON_POSSIBLE_VALUES check on off)
-  set(PNG_ARM_NEON "check" CACHE STRING "Enable ARM NEON optimizations:
-     check: (default) use internal checking code;
-     off: disable the optimizations;
-     on: turn on unconditionally.")
-  set_property(CACHE PNG_ARM_NEON PROPERTY STRINGS
-     ${PNG_ARM_NEON_POSSIBLE_VALUES})
-  list(FIND PNG_ARM_NEON_POSSIBLE_VALUES ${PNG_ARM_NEON} index)
-  if(index EQUAL -1)
-    message(FATAL_ERROR
-      " PNG_ARM_NEON must be one of [${PNG_ARM_NEON_POSSIBLE_VALUES}]")
-  elseif(NOT ${PNG_ARM_NEON} STREQUAL "no")
-    set(libpng_arm_sources
-      arm/arm_init.c
-      arm/filter_neon.S
-      arm/filter_neon_intrinsics.c)
-
-    if(${PNG_ARM_NEON} STREQUAL "on")
-      add_definitions(-DPNG_ARM_NEON_OPT=2)
-    elseif(${PNG_ARM_NEON} STREQUAL "check")
-      add_definitions(-DPNG_ARM_NEON_CHECK_SUPPORTED)
-    endif()
-  else()
-    add_definitions(-DPNG_ARM_NEON_OPT=0)
-  endif()
-endif()
-
-# set definitions and sources for powerpc
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^powerpc*" OR
-	CMAKE_SYSTEM_PROCESSOR MATCHES "^ppc64*" )
-  set(PNG_POWERPC_VSX_POSSIBLE_VALUES on off)
-  set(PNG_POWERPC_VSX "on" CACHE STRING "Enable POWERPC VSX optimizations:
-     off: disable the optimizations.")
-  set_property(CACHE PNG_POWERPC_VSX PROPERTY STRINGS
-     ${PNG_POWERPC_VSX_POSSIBLE_VALUES})
-  list(FIND PNG_POWERPC_VSX_POSSIBLE_VALUES ${PNG_POWERPC_VSX} index)
-  if(index EQUAL -1)
-    message(FATAL_ERROR
-      " PNG_POWERPC_VSX must be one of [${PNG_POWERPC_VSX_POSSIBLE_VALUES}]")
-  elseif(NOT ${PNG_POWERPC_VSX} STREQUAL "no")
-    set(libpng_powerpc_sources
-      powerpc/powerpc_init.c
-      powerpc/filter_vsx_intrinsics.c)
-    if(${PNG_POWERPC_VSX} STREQUAL "on")
-      add_definitions(-DPNG_POWERPC_VSX_OPT=2)
-    endif()
-  else()
-    add_definitions(-DPNG_POWERPC_VSX_OPT=0)
-  endif()
-endif()
-
-# set definitions and sources for intel
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^i?86" OR
-	CMAKE_SYSTEM_PROCESSOR MATCHES "^x86_64*" )
-  set(PNG_INTEL_SSE_POSSIBLE_VALUES on off)
-  set(PNG_INTEL_SSE "on" CACHE STRING "Enable INTEL_SSE optimizations:
-     off: disable the optimizations")
-  set_property(CACHE PNG_INTEL_SSE PROPERTY STRINGS
-     ${PNG_INTEL_SSE_POSSIBLE_VALUES})
-  list(FIND PNG_INTEL_SSE_POSSIBLE_VALUES ${PNG_INTEL_SSE} index)
-  if(index EQUAL -1)
-    message(FATAL_ERROR
-      " PNG_INTEL_SSE must be one of [${PNG_INTEL_SSE_POSSIBLE_VALUES}]")
-  elseif(NOT ${PNG_INTEL_SSE} STREQUAL "no")
-    set(libpng_intel_sources
-      intel/intel_init.c
-      intel/filter_sse2_intrinsics.c)
-    if(${PNG_INTEL_SSE} STREQUAL "on")
-      add_definitions(-DPNG_INTEL_SSE_OPT=1)
-    endif()
-  else()
-    add_definitions(-DPNG_INTEL_SSE_OPT=0)
-  endif()
-endif()
-
-# set definitions and sources for MIPS
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "mipsel*" OR
-	CMAKE_SYSTEM_PROCESSOR MATCHES "mips64el*" )
-  set(PNG_MIPS_MSA_POSSIBLE_VALUES on off)
-  set(PNG_MIPS_MSA "on" CACHE STRING "Enable MIPS_MSA optimizations:
-     off: disable the optimizations")
-  set_property(CACHE PNG_MIPS_MSA PROPERTY STRINGS
-     ${PNG_MIPS_MSA_POSSIBLE_VALUES})
-  list(FIND PNG_MIPS_MSA_POSSIBLE_VALUES ${PNG_MIPS_MSA} index)
-  if(index EQUAL -1)
-    message(FATAL_ERROR
-      " PNG_MIPS_MSA must be one of [${PNG_MIPS_MSA_POSSIBLE_VALUES}]")
-  elseif(NOT ${PNG_MIPS_MSA} STREQUAL "no")
-    set(libpng_mips_sources
-      mips/mips_init.c
-      mips/filter_msa_intrinsics.c)
-    if(${PNG_MIPS_MSA} STREQUAL "on")
-      add_definitions(-DPNG_MIPS_MSA_OPT=2)
-    endif()
-  else()
-    add_definitions(-DPNG_MIPS_MSA_OPT=0)
-  endif()
-endif()
-endif(PNG_HARDWARE_OPTIMIZATIONS)
-
 # SET LIBNAME
 set(PNG_LIB_NAME png${PNGLIB_MAJOR}${PNGLIB_MINOR})

 # to distinguish between debug and release lib
 set(CMAKE_DEBUG_POSTFIX "d")

-include(CheckCSourceCompiles)
-option(ld-version-script "Enable linker version script" ON)
-if(ld-version-script AND NOT APPLE)
-  # Check if LD supports linker scripts.
-  file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/conftest.map" "VERS_1 {
-        global: sym;
-        local: *;
-};
-
-VERS_2 {
-        global: sym2;
-                main;
-} VERS_1;
-")
-  set(CMAKE_REQUIRED_FLAGS_SAVE ${CMAKE_REQUIRED_FLAGS})
-  set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS} "-Wl,--version-script='${CMAKE_CURRENT_BINARY_DIR}/conftest.map'")
-  check_c_source_compiles("void sym(void) {}
-void sym2(void) {}
-int main(void) {return 0;}
-" HAVE_LD_VERSION_SCRIPT)
-  if(NOT HAVE_LD_VERSION_SCRIPT)
-    set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS_SAVE} "-Wl,-M -Wl,${CMAKE_CURRENT_BINARY_DIR}/conftest.map")
-  check_c_source_compiles("void sym(void) {}
-void sym2(void) {}
-int main(void) {return 0;}
-" HAVE_SOLARIS_LD_VERSION_SCRIPT)
-  endif()
-  set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS_SAVE})
-  file(REMOVE "${CMAKE_CURRENT_BINARY_DIR}/conftest.map")
-endif()
-
-# Find symbol prefix.  Likely obsolete and unnecessary with recent
-# toolchains (it's not done in many other projects).
-function(symbol_prefix)
-  set(SYMBOL_PREFIX)
-
-  execute_process(COMMAND "${CMAKE_C_COMPILER}" "-E" "-"
-                  INPUT_FILE /dev/null
-                  OUTPUT_VARIABLE OUT
-                  RESULT_VARIABLE STATUS)
-
-  if(CPP_FAIL)
-    message(WARNING "Failed to run the C preprocessor")
-  endif()
-
-  string(REPLACE "\n" ";" OUT "${OUT}")
-  foreach(line ${OUT})
-    string(REGEX MATCH "^PREFIX=" found_match "${line}")
-    if(found_match)
-      STRING(REGEX REPLACE "^PREFIX=(.*\)" "\\1" prefix "${line}")
-      string(REGEX MATCH "__USER_LABEL_PREFIX__" found_match "${prefix}")
-      if(found_match)
-        STRING(REGEX REPLACE "(.*)__USER_LABEL_PREFIX__(.*)" "\\1\\2" prefix "${prefix}")
-      endif()
-      set(SYMBOL_PREFIX "${prefix}")
-    endif()
-  endforeach()
-
-    message(STATUS "Symbol prefix: ${SYMBOL_PREFIX}")
-    set(SYMBOL_PREFIX "${SYMBOL_PREFIX}" PARENT_SCOPE)
-endfunction()
-
-if(UNIX)
-  symbol_prefix()
-endif()
-
-find_program(AWK NAMES gawk awk)
-
+# 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})

-if(NOT AWK OR ANDROID)
-  # No awk available to generate sources; use pre-built pnglibconf.h
-  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt
-                 ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h)
-  add_custom_target(genfiles) # Dummy
-else()
-  include(CMakeParseArguments)
-  # Generate .chk from .out with awk
-  # generate_chk(INPUT inputfile OUTPUT outputfile [DEPENDS dep1 [dep2...]])
-  function(generate_chk)
-    set(options)
-    set(oneValueArgs INPUT OUTPUT)
-    set(multiValueArgs DEPENDS)
-    cmake_parse_arguments(_GC "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
-    if (NOT _GC_INPUT)
-      message(FATAL_ERROR "Invalid arguments.  generate_out requires input.")
-    endif()
-    if (NOT _GC_OUTPUT)
-      message(FATAL_ERROR "Invalid arguments.  generate_out requires output.")
-    endif()
-
-    add_custom_command(OUTPUT "${_GC_OUTPUT}"
-                       COMMAND "${CMAKE_COMMAND}"
-                               "-DINPUT=${_GC_INPUT}"
-                               "-DOUTPUT=${_GC_OUTPUT}"
-                               -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/genchk.cmake"
-                       DEPENDS "${_GC_INPUT}" ${_GC_DEPENDS}
-                       WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
-  endfunction()
-
-  # Generate .out from .c with awk
-  # generate_out(INPUT inputfile OUTPUT outputfile [DEPENDS dep1 [dep2...]])
-  function(generate_out)
-    set(options)
-    set(oneValueArgs INPUT OUTPUT)
-    set(multiValueArgs DEPENDS)
-    cmake_parse_arguments(_GO "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
-    if (NOT _GO_INPUT)
-      message(FATAL_ERROR "Invalid arguments.  generate_out requires input.")
-    endif()
-    if (NOT _GO_OUTPUT)
-      message(FATAL_ERROR "Invalid arguments.  generate_out requires output.")
-    endif()
-
-    add_custom_command(OUTPUT "${_GO_OUTPUT}"
-                       COMMAND "${CMAKE_COMMAND}"
-                               "-DINPUT=${_GO_INPUT}"
-                               "-DOUTPUT=${_GO_OUTPUT}"
-                               -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/genout.cmake"
-                       DEPENDS "${_GO_INPUT}" ${_GO_DEPENDS}
-                       WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
-  endfunction()
-
-  # Generate specific source file with awk
-  # generate_source(OUTPUT outputfile [DEPENDS dep1 [dep2...]])
-  function(generate_source)
-    set(options)
-    set(oneValueArgs OUTPUT)
-    set(multiValueArgs DEPENDS)
-    cmake_parse_arguments(_GSO "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
-    if (NOT _GSO_OUTPUT)
-      message(FATAL_ERROR "Invalid arguments.  generate_source requires output.")
-    endif()
-
-    add_custom_command(OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/${_GSO_OUTPUT}"
-                       COMMAND "${CMAKE_COMMAND}"
-                               "-DOUTPUT=${_GSO_OUTPUT}"
-                               -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake"
-                       DEPENDS ${_GSO_DEPENDS}
-                       WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
-  endfunction()
-
-  # Copy file
-  function(generate_copy source destination)
-    add_custom_command(OUTPUT "${destination}"
-                       COMMAND "${CMAKE_COMMAND}" -E remove "${destination}"
-                       COMMAND "${CMAKE_COMMAND}" -E copy "${source}"
-                                                          "${destination}"
-                       DEPENDS "${source}")
-  endfunction()
-
-  # Generate scripts/pnglibconf.h
-  generate_source(OUTPUT "scripts/pnglibconf.c"
-                  DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.dfa"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/scripts/options.awk"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h")
-
-  # Generate pnglibconf.c
-  generate_source(OUTPUT "pnglibconf.c"
-                  DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.dfa"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/scripts/options.awk"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h")
-
-  if(PNG_PREFIX)
-    set(PNGLIBCONF_H_EXTRA_DEPENDS
-        "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out"
-        "${CMAKE_CURRENT_SOURCE_DIR}/scripts/macro.lst")
-    set(PNGPREFIX_H_EXTRA_DEPENDS
-        "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out")
-  endif()
-
-  generate_out(INPUT "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out")
-
-  # Generate pnglibconf.h
-  generate_source(OUTPUT "pnglibconf.h"
-                  DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out"
-                          ${PNGLIBCONF_H_EXTRA_DEPENDS})
-
-  generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/intprefix.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out"
-               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
-
-  generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/prefix.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out"
-               DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
-                       "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
-                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out")
-
-  # Generate pngprefix.h
-  generate_source(OUTPUT "pngprefix.h"
-                  DEPENDS ${PNGPREFIX_H_EXTRA_DEPENDS})
-
-  generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/sym.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
-
-  generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/symbols.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
-               DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
-                       "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
-                       "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt")
-
-  generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/vers.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out"
-               DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
-                       "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
-                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
-
-  generate_chk(INPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk"
-               DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/checksym.awk"
-                       "${CMAKE_CURRENT_SOURCE_DIR}/scripts/symbols.def")
-
-  add_custom_target(symbol-check DEPENDS
-                    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk")
-
-  generate_copy("${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-                "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym")
-  generate_copy("${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out"
-                "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers")
-
-  add_custom_target(genvers DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers")
-  add_custom_target(gensym DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym")
-
-  add_custom_target("genprebuilt"
-                    COMMAND "${CMAKE_COMMAND}"
-                            "-DOUTPUT=scripts/pnglibconf.h.prebuilt"
-                            -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake"
-                    WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
-
-  # A single target handles generation of all generated files.  If
-  # they are dependend upon separately by multiple targets, this
-  # confuses parallel make (it would require a separate top-level
-  # target for each file to track the dependencies properly).
-  add_custom_target(genfiles DEPENDS
-    "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym"
-    "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/pnglibconf.c"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out")
-endif(NOT AWK OR ANDROID)
-
 # OUR SOURCES
 set(libpng_public_hdrs
  png.h
  pngconf.h
-  "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
+  ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h
 )
-set(libpng_private_hdrs
-  pngpriv.h
-  pngdebug.h
-  pnginfo.h
-  pngstruct.h
-)
-if(AWK AND NOT ANDROID)
-  list(APPEND libpng_private_hdrs "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h")
-endif()
 set(libpng_sources
  ${libpng_public_hdrs}
-  ${libpng_private_hdrs}
+  pngdebug.h
+  pnginfo.h
+  pngpriv.h
+  pngstruct.h
  png.c
  pngerror.c
  pngget.c
@@ -476,10 +88,6 @@ set(libpng_sources
  pngwrite.c
  pngwtran.c
  pngwutil.c
-  ${libpng_arm_sources}
-  ${libpng_intel_sources}
-  ${libpng_mips_sources}
-  ${libpng_powerpc_sources}
 )
 set(pngtest_sources
  pngtest.c
@@ -490,18 +98,7 @@ set(pngvalid_sources
 set(pngstest_sources
  contrib/libtests/pngstest.c
 )
-set(pngunknown_sources
-  contrib/libtests/pngunknown.c
-)
-set(pngimage_sources
-  contrib/libtests/pngimage.c
-)
-set(pngfix_sources
-  contrib/tools/pngfix.c
-)
-set(png_fix_itxt_sources
-  contrib/tools/png-fix-itxt.c
-)
+# SOME NEEDED DEFINITIONS

 if(MSVC)
  add_definitions(-D_CRT_SECURE_NO_DEPRECATE)
@@ -517,59 +114,33 @@ include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${ZLIB_INCLUDE_DIR})
 unset(PNG_LIB_TARGETS)

 if(PNG_SHARED)
-  add_library(png SHARED ${libpng_sources})
-  set(PNG_LIB_TARGETS png)
-  set_target_properties(png PROPERTIES OUTPUT_NAME ${PNG_LIB_NAME})
-  add_dependencies(png genfiles)
+  add_library(${PNG_LIB_NAME} SHARED ${libpng_sources})
+  set(PNG_LIB_TARGETS ${PNG_LIB_NAME})
  if(MSVC)
    # msvc does not append 'lib' - do it here to have consistent name
-    set_target_properties(png PROPERTIES PREFIX "lib")
-    set_target_properties(png PROPERTIES IMPORT_PREFIX "lib")
-  endif()
-  target_link_libraries(png ${ZLIB_LIBRARY} ${M_LIBRARY})
-
-  if(UNIX AND AWK)
-    if(HAVE_LD_VERSION_SCRIPT)
-      set_target_properties(png PROPERTIES LINK_FLAGS
-        "-Wl,--version-script='${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
-    elseif(HAVE_SOLARIS_LD_VERSION_SCRIPT)
-      set_target_properties(png PROPERTIES LINK_FLAGS
-        "-Wl,-M -Wl,'${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
-    endif()
+    set_target_properties(${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_static)
-  add_library(png_static STATIC ${libpng_sources})
-  add_dependencies(png_static genfiles)
-  # MSVC doesn't use a different file extension for shared vs. static
-  # libs.  We are able to change OUTPUT_NAME to remove the _static
-  # for all other platforms.
-  if(NOT MSVC)
-    set_target_properties(png_static PROPERTIES
-      OUTPUT_NAME "${PNG_LIB_NAME}"
-      CLEAN_DIRECT_OUTPUT 1)
-  else()
-    set_target_properties(png_static PROPERTIES
-      OUTPUT_NAME "${PNG_LIB_NAME}_static"
-      CLEAN_DIRECT_OUTPUT 1)
-  endif()
-  list(APPEND PNG_LIB_TARGETS png_static)
+  set(PNG_LIB_NAME_STATIC ${PNG_LIB_NAME}_static)
+  add_library(${PNG_LIB_NAME_STATIC} STATIC ${libpng_sources})
+  list(APPEND PNG_LIB_TARGETS ${PNG_LIB_NAME_STATIC})
  if(MSVC)
    # msvc does not append 'lib' - do it here to have consistent name
-    set_target_properties(png_static PROPERTIES PREFIX "lib")
+    set_target_properties(${PNG_LIB_NAME_STATIC} PROPERTIES PREFIX "lib")
  endif()
-  target_link_libraries(png_static ${ZLIB_LIBRARY} ${M_LIBRARY})
+  target_link_libraries(${PNG_LIB_NAME_STATIC} ${ZLIB_LIBRARY} ${M_LIBRARY})
 endif()

 if(PNG_FRAMEWORK)
-  set(PNG_LIB_NAME_FRAMEWORK png_framework)
-  add_library(png_framework SHARED ${libpng_sources})
-  add_dependencies(png_framework genfiles)
-  list(APPEND PNG_LIB_TARGETS png_framework)
-  set_target_properties(png_framework PROPERTIES
+  set(PNG_LIB_NAME_FRAMEWORK ${PNG_LIB_NAME}_framework)
+  add_library(${PNG_LIB_NAME_FRAMEWORK} SHARED ${libpng_sources})
+  list(APPEND PNG_LIB_TARGETS ${PNG_LIB_NAME_FRAMEWORK})
+  set_target_properties(${PNG_LIB_NAME_FRAMEWORK} PROPERTIES
    FRAMEWORK TRUE
    FRAMEWORK_VERSION ${PNGLIB_VERSION}
    MACOSX_FRAMEWORK_SHORT_VERSION_STRING ${PNGLIB_MAJOR}.${PNGLIB_MINOR}
@@ -578,7 +149,7 @@ if(PNG_FRAMEWORK)
    XCODE_ATTRIBUTE_INSTALL_PATH "@rpath"
    PUBLIC_HEADER "${libpng_public_hdrs}"
    OUTPUT_NAME png)
-  target_link_libraries(png_framework ${ZLIB_LIBRARY} ${M_LIBRARY})
+  target_link_libraries(${PNG_LIB_NAME_FRAMEWORK} ${ZLIB_LIBRARY} ${M_LIBRARY})
 endif()

 if(NOT PNG_LIB_TARGETS)
@@ -589,233 +160,79 @@ if(NOT PNG_LIB_TARGETS)
 endif()

 if(PNG_SHARED AND WIN32)
-  set_target_properties(png PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)
+  set_target_properties(${PNG_LIB_NAME} PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)
 endif()

-function(png_add_test)
-  set(options)
-  set(oneValueArgs NAME COMMAND)
-  set(multiValueArgs OPTIONS FILES)
-  cmake_parse_arguments(_PAT "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
-
-  if (NOT _PAT_NAME)
-    message(FATAL_ERROR "Invalid arguments.  png_add_test requires name.")
-  endif()
-  if (NOT _PAT_COMMAND)
-    message(FATAL_ERROR "Invalid arguments.  png_add_test requires command.")
-  endif()
-
-  set(TEST_OPTIONS "${_PAT_OPTIONS}")
-  set(TEST_FILES "${_PAT_FILES}")
-
-  configure_file("${CMAKE_CURRENT_SOURCE_DIR}/scripts/test.cmake.in"
-                 "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake" @ONLY)
-  if(CMAKE_MAJOR_VERSION GREATER 2) # have generator expressions
-    add_test(NAME "${_PAT_NAME}"
-             COMMAND "${CMAKE_COMMAND}"
-             "-DLIBPNG=$<TARGET_FILE:png>"
-             "-DTEST_COMMAND=$<TARGET_FILE:${_PAT_COMMAND}>"
-             -P "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake")
-  else() # old 2.x add_test; limited and won't work well on Windows
-    # Note LIBPNG is a dummy value as there are no generator expressions
-    add_test("${_PAT_NAME}" "${CMAKE_COMMAND}"
-             "-DLIBPNG=${CMAKE_CURRENT_BINARY_DIR}/libpng.so"
-             "-DTEST_COMMAND=./${_PAT_COMMAND}"
-             -P "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake")
-  endif()
-endfunction()
-
 if(PNG_TESTS AND PNG_SHARED)
-  # Find test PNG files by globbing, but sort lists to ensure
-  # consistency between different filesystems.
-  file(GLOB PNGSUITE_PNGS "${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/*.png")
-  list(SORT PNGSUITE_PNGS)
-  file(GLOB TEST_PNGS "${CMAKE_CURRENT_SOURCE_DIR}/contrib/testpngs/*.png")
-  list(SORT TEST_PNGS)
-
-  set(PNGTEST_PNG "${CMAKE_CURRENT_SOURCE_DIR}/pngtest.png")
-
+  # does not work with msvc due to png_lib_ver issue
  add_executable(pngtest ${pngtest_sources})
-  target_link_libraries(pngtest png)
-
-  png_add_test(NAME pngtest COMMAND pngtest FILES "${PNGTEST_PNG}")
-
+  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)
-
-  png_add_test(NAME pngvalid-gamma-16-to-8
-               COMMAND pngvalid OPTIONS --gamma-16-to-8)
-  png_add_test(NAME pngvalid-gamma-alpha-mode
-               COMMAND pngvalid OPTIONS --gamma-alpha-mode)
-  png_add_test(NAME pngvalid-gamma-background
-               COMMAND pngvalid OPTIONS --gamma-background)
-  png_add_test(NAME pngvalid-gamma-expand16-alpha-mode
-               COMMAND pngvalid OPTIONS --gamma-alpha-mode --expand16)
-  png_add_test(NAME pngvalid-gamma-expand16-background
-               COMMAND pngvalid OPTIONS --gamma-background --expand16)
-  png_add_test(NAME pngvalid-gamma-expand16-transform
-               COMMAND pngvalid OPTIONS --gamma-transform --expand16)
-  png_add_test(NAME pngvalid-gamma-sbit
-               COMMAND pngvalid OPTIONS --gamma-sbit)
-  png_add_test(NAME pngvalid-gamma-threshold
-               COMMAND pngvalid OPTIONS --gamma-threshold)
-  png_add_test(NAME pngvalid-gamma-transform
-               COMMAND pngvalid OPTIONS --gamma-transform)
-  png_add_test(NAME pngvalid-progressive-interlace-standard
-               COMMAND pngvalid OPTIONS --standard --progressive-read --interlace)
-  png_add_test(NAME pngvalid-progressive-size
-               COMMAND pngvalid OPTIONS --size --progressive-read)
-  png_add_test(NAME pngvalid-progressive-standard
-               COMMAND pngvalid OPTIONS --standard --progressive-read)
-  png_add_test(NAME pngvalid-standard
-               COMMAND pngvalid OPTIONS --standard)
-  png_add_test(NAME pngvalid-transform
-               COMMAND pngvalid OPTIONS --transform)
-
+  target_link_libraries(pngvalid ${PNG_LIB_NAME})
+  add_test(pngvalid ./pngvalid)
  add_executable(pngstest ${pngstest_sources})
-  target_link_libraries(pngstest png)
-
-  foreach(gamma_type 1.8 linear none sRGB)
-    foreach(alpha_type none alpha)
-      set(PNGSTEST_FILES)
-      foreach(test_png ${TEST_PNGS})
-        string(REGEX MATCH ".*-linear[-.].*" TEST_PNG_LINEAR "${test_png}")
-        string(REGEX MATCH ".*-sRGB[-.].*" TEST_PNG_SRGB "${test_png}")
-        string(REGEX MATCH ".*-1.8[-.].*" TEST_PNG_G18 "${test_png}")
-        string(REGEX MATCH ".*-alpha-.*" TEST_PNG_ALPHA "${test_png}")
-
-        set(TEST_PNG_VALID TRUE)
-
-        if(TEST_PNG_ALPHA)
-          if (NOT "${alpha_type}" STREQUAL "alpha")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        else()
-          if ("${alpha_type}" STREQUAL "alpha")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        endif()
-
-        if(TEST_PNG_LINEAR)
-          if(NOT "${gamma_type}" STREQUAL "linear")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        elseif(TEST_PNG_SRGB)
-          if(NOT "${gamma_type}" STREQUAL "sRGB")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        elseif(TEST_PNG_G18)
-          if(NOT "${gamma_type}" STREQUAL "1.8")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        else()
-          if(NOT "${gamma_type}" STREQUAL "none")
-            set(TEST_PNG_VALID FALSE)
-          endif()
-        endif()
-
-        if(TEST_PNG_VALID)
-          list(APPEND PNGSTEST_FILES "${test_png}")
-        endif()
-      endforeach()
-      # Should already be sorted, but sort anyway to be certain.
-      list(SORT PNGSTEST_FILES)
-      png_add_test(NAME pngstest-${gamma_type}-${alpha_type}
-                   COMMAND pngstest
-                   OPTIONS --tmpfile "${gamma_type}-${alpha_type}-" --log
-                   FILES ${PNGSTEST_FILES})
-    endforeach()
-  endforeach()
-
-  add_executable(pngunknown ${pngunknown_sources})
-  target_link_libraries(pngunknown png)
-
-  png_add_test(NAME pngunknown-discard COMMAND pngunknown OPTIONS --strict default=discard FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-IDAT COMMAND pngunknown OPTIONS --strict default=discard IDAT=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-if-safe COMMAND pngunknown OPTIONS --strict default=if-safe FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-sAPI COMMAND pngunknown OPTIONS --strict bKGD=save cHRM=save gAMA=save all=discard iCCP=save sBIT=save sRGB=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-save COMMAND pngunknown OPTIONS --strict default=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-sTER COMMAND pngunknown OPTIONS --strict sTER=if-safe FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-vpAg COMMAND pngunknown OPTIONS --strict vpAg=if-safe FILES "${PNGTEST_PNG}")
-
-  add_executable(pngimage ${pngimage_sources})
-  target_link_libraries(pngimage png)
-
-  png_add_test(NAME pngimage-quick COMMAND pngimage OPTIONS --list-combos --log FILES ${PNGSUITE_PNGS})
-  png_add_test(NAME pngimage-full COMMAND pngimage OPTIONS --exhaustive --list-combos --log FILES ${PNGSUITE_PNGS})
+  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()

-if(PNG_SHARED)
-  add_executable(pngfix ${pngfix_sources})
-  target_link_libraries(pngfix png)
-  set(PNG_BIN_TARGETS pngfix)
-
-  add_executable(png-fix-itxt ${png_fix_itxt_sources})
-  target_link_libraries(png-fix-itxt ${ZLIB_LIBRARY} ${M_LIBRARY})
-  list(APPEND PNG_BIN_TARGETS png-fix-itxt)
-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.
-include(CMakeParseArguments)
-
-function(CREATE_SYMLINK DEST_FILE)
-
-  cmake_parse_arguments(S "" "FILE;TARGET" "" ${ARGN})
-
-  if(NOT S_TARGET AND NOT S_FILE)
-    message(FATAL_ERROR "Specify either a TARGET or a FILE for CREATE_SYMLINK to link to.")
-  endif(NOT S_TARGET AND NOT S_FILE)
-
-  if(S_TARGET AND S_FILE)
-    message(FATAL_ERROR "CREATE_SYMLINK called with both source file ${S_FILE} and build target ${S_TARGET} arguments - can only handle 1 type per call.")
-  endif(S_TARGET AND S_FILE)
-
-  if(S_FILE)
-    # If we don't need to symlink something that's coming from a build target,
-    # we can go ahead and symlink/copy at configure time.
-
-    if(CMAKE_HOST_WIN32 AND NOT CYGWIN AND NOT MSYS)
-      execute_process(
-	COMMAND "${CMAKE_COMMAND}" -E copy_if_different ${S_FILE} ${DEST_FILE}
-	WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}"
-	)
-    else(CMAKE_HOST_WIN32 AND NOT CYGWIN AND NOT MSYS)
-      execute_process(
-	COMMAND ${CMAKE_COMMAND} -E create_symlink ${S_FILE} ${DEST_FILE}
-	WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}"
-	)
-    endif(CMAKE_HOST_WIN32 AND NOT CYGWIN AND NOT MSYS)
-  endif(S_FILE)
-
-  if(S_TARGET)
-    # We need to use generator expressions, which can be a bit tricky, so for
-    # simplicity make the symlink a POST_BUILD step and use the TARGET
-    # signature of add_custom_command.
-
-    if(CMAKE_HOST_WIN32 AND NOT CYGWIN AND NOT MSYS)
-      add_custom_command(TARGET ${S_TARGET} POST_BUILD
-	COMMAND "${CMAKE_COMMAND}" -E copy_if_different $<TARGET_LINKER_FILE_NAME:${S_TARGET}> $<TARGET_LINKER_FILE_DIR:${S_TARGET}>/${DEST_FILE}
-	)
-    else(CMAKE_HOST_WIN32 AND NOT CYGWIN AND NOT MSYS)
-      add_custom_command(TARGET ${S_TARGET} POST_BUILD
-	COMMAND "${CMAKE_COMMAND}" -E create_symlink $<TARGET_LINKER_FILE_NAME:${S_TARGET}> $<TARGET_LINKER_FILE_DIR:${S_TARGET}>/${DEST_FILE}
-	)
-    endif(CMAKE_HOST_WIN32 AND NOT CYGWIN AND NOT MSYS)
-
-  endif(S_TARGET)
-
-endfunction()
-
-# Create source generation scripts.
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/genchk.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/genchk.cmake @ONLY)
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/genout.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/genout.cmake @ONLY)
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/gensrc.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake @ONLY)
-
+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 ${CMAKE_COMMAND} -E copy_if_different  "${SRC_FILE}" ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE}
+        COMMAND ${CMAKE_COMMAND} -E copy_if_different  "${SRC_FILE}" ${CMAKE_CURRENT_BINARY_DIR}/${DEST_FILE}
+        DEPENDS ${PNG_LIB_TARGETS}
+        )
+    ADD_CUSTOM_TARGET(${DEST_FILE}_COPY ALL DEPENDS ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE})
+  else(WIN32 AND NOT CYGWIN AND NOT MSYS)
+    get_filename_component(LINK_TARGET "${SRC_FILE}" NAME)
+    execute_process(COMMAND ${CMAKE_COMMAND} -E make_directory ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_LIBRARY_OUTPUT_DIRECTORY})
+    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${LINK_TARGET}" ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${LINK_TARGET}" ${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)
@@ -834,21 +251,31 @@ if(NOT WIN32 OR CYGWIN OR MINGW)
  set(LIBS        "-lz -lm")
  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng.pc.in
    ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc @ONLY)
-  CREATE_SYMLINK(libpng.pc FILE ${PNGLIB_NAME}.pc)
+  CREATE_SYMLINK(${PNGLIB_NAME}.pc libpng.pc)

  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng-config.in
    ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config @ONLY)
-  CREATE_SYMLINK(libpng-config FILE ${PNGLIB_NAME}-config)
+  CREATE_SYMLINK(${PNGLIB_NAME}-config libpng-config)
 endif(NOT WIN32 OR CYGWIN OR MINGW)

 # SET UP LINKS
 if(PNG_SHARED)
-  set_target_properties(png PROPERTIES
-#   VERSION 16.${PNGLIB_RELEASE}.1.6.34
+  set_target_properties(${PNG_LIB_NAME} PROPERTIES
+#   VERSION 16.${PNGLIB_RELEASE}.1.6.17
    VERSION 16.${PNGLIB_RELEASE}.0
    SOVERSION 16
    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.
@@ -871,20 +298,26 @@ if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL )
  if(PNG_SHARED)
    # Create a symlink for libpng.dll.a => libpng16.dll.a on Cygwin
    if(CYGWIN OR MINGW)
-      CREATE_SYMLINK(libpng${CMAKE_IMPORT_LIBRARY_SUFFIX} TARGET png)
-      install(FILES $<TARGET_LINKER_FILE_DIR:png>/libpng${CMAKE_IMPORT_LIBRARY_SUFFIX} DESTINATION ${CMAKE_INSTALL_LIBDIR})
+       get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})
+       CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${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)
-      CREATE_SYMLINK(libpng${CMAKE_SHARED_LIBRARY_SUFFIX} TARGET png)
-      install(FILES $<TARGET_LINKER_FILE_DIR:png>/libpng${CMAKE_SHARED_LIBRARY_SUFFIX} DESTINATION ${CMAKE_INSTALL_LIBDIR})
+      get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME} LOCATION_${CMAKE_BUILD_TYPE})
+      CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${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)
    if(NOT WIN32 OR CYGWIN OR MINGW)
-      CREATE_SYMLINK( libpng${CMAKE_STATIC_LIBRARY_SUFFIX} TARGET png_static)
-      install(FILES $<TARGET_LINKER_FILE_DIR:png_static>/libpng${CMAKE_STATIC_LIBRARY_SUFFIX} DESTINATION ${CMAKE_INSTALL_LIBDIR})
+      get_target_property(BUILD_TARGET_LOCATION ${PNG_LIB_NAME_STATIC} LOCATION_${CMAKE_BUILD_TYPE})
+      CREATE_SYMLINK(${BUILD_TARGET_LOCATION} libpng${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()
@@ -901,11 +334,6 @@ if(NOT SKIP_INSTALL_EXECUTABLES AND NOT SKIP_INSTALL_ALL )
  endif(NOT WIN32 OR CYGWIN OR MINGW)
 endif()

-if(NOT SKIP_INSTALL_PROGRAMS AND NOT SKIP_INSTALL_ALL )
-  install(TARGETS ${PNG_BIN_TARGETS}
-      RUNTIME DESTINATION bin)
-endif()
-
 if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
  # Install man pages
  if(NOT PNG_MAN_DIR)
@@ -914,7 +342,7 @@ if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
  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 CMAKE_HOST_WIN32 OR CYGWIN OR MINGW)
+  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
@@ -923,7 +351,7 @@ if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
            DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config
            DESTINATION bin)
-  endif(NOT CMAKE_HOST_WIN32 OR CYGWIN OR MINGW)
+  endif(NOT WIN32 OR CYGWIN OR MINGW)
 endif()

 # On versions of CMake that support it, create an export file CMake
@@ -943,3 +371,4 @@ endif()
 # to create msvc import lib for mingw compiled shared lib
 # pexports libpng.dll > libpng.def
 # lib /def:libpng.def /machine:x86
+
--- a/178
+++ b/178
@@ -1,26 +1,24 @@

-    Installing libpng
+Installing libpng

 Contents

-       I. Simple installation
-      II. Rebuilding the configure scripts
-     III. Using scripts/makefile*
-      IV. Using cmake
-       V. Directory structure
-      VI. Building with project files
-     VII. Building with makefiles
-    VIII. Configuring libpng for 16-bit platforms
-      IX. Configuring for DOS
-       X. Configuring for Medium Model
-      XI. Prepending a prefix to exported symbols
-     XII. Configuring for compiler xxx:
-    XIII. Removing unwanted object code
-     XIV. Enabling or disabling hardware optimizations
-      XV. Changes to the build and configuration of libpng in libpng-1.5.x
-     XVI. Setjmp/longjmp issues
-    XVII. Common linking failures
-   XVIII. Other sources of information about libpng
+   I. Simple installation
+  II. Rebuilding the configure scripts
+ III. Using scripts/makefile*
+  IV. Using cmake
+   V. Directory structure
+  VI. Building with project files
+ VII. Building with makefiles
+VIII. Configuring libpng for 16-bit platforms
+  IX. Configuring for DOS
+   X. Configuring for Medium Model
+  XI. Prepending a prefix to exported symbols
+ XII. Configuring for compiler xxx:
+XIII. Removing unwanted object code
+ XIV. Changes to the build and configuration of libpng in libpng-1.5.x
+  XV. Setjmp/longjmp issues
+ XVI. Other sources of information about libpng

 I. Simple installation

@@ -49,9 +47,7 @@ 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, especially if you
-are building from a tar distribution instead of a git distribution,
-do this:
+aren't using any of the included pre-built scripts, you can do this:

    ./configure --enable-maintainer-mode
    make maintainer-clean
@@ -79,8 +75,8 @@ Or you can use one of the "projects" in the "projects" directory.

 Before installing libpng, you must first install zlib, if it
 is not already on your system.  zlib can usually be found
-wherever you got libpng; otherwise go to https://zlib.net/.  You can
-place zlib in the same directory as libpng or in another directory.
+wherever you got libpng; otherwise go to http://zlib.net.  You can place
+zlib in in the same directory as libpng or in another directory.

 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
@@ -91,24 +87,22 @@ standard library search path, put ZLIBLIB, ZLIBINC, CPPFLAGS, LDFLAGS,
 and LD_LIBRARY_PATH in your environment before running "make test"
 or "make distcheck":

-    ZLIBLIB=/path/to/lib export ZLIBLIB
-    ZLIBINC=/path/to/include export ZLIBINC
-    CPPFLAGS="-I$ZLIBINC" export CPPFLAGS
-    LDFLAGS="-L$ZLIBLIB" export LDFLAGS
-    LD_LIBRARY_PATH="$ZLIBLIB:$LD_LIBRARY_PATH" export LD_LIBRARY_PATH
+ZLIBLIB=/path/to/lib export ZLIBLIB
+ZLIBINC=/path/to/include export ZLIBINC
+CPPFLAGS="-I$ZLIBINC" export CPPFLAGS
+LDFLAGS="-L$ZLIBLIB" export LDFLAGS
+LD_LIBRARY_PATH="$ZLIBLIB:$LD_LIBRARY_PATH" export LD_LIBRARY_PATH

 If you are using one of the makefile scripts, put ZLIBLIB and ZLIBINC
-in your environment and type
-
-    make ZLIBLIB=$ZLIBLIB ZLIBINC=$ZLIBINC test
+in your environment and type "make ZLIBLIB=$ZLIBLIB ZLIBINC=$ZLIBINC test".

 IV. Using cmake

 If you want to use "cmake" (see www.cmake.org), type

-    cmake . -DCMAKE_INSTALL_PREFIX=/path
-    make
-    make install
+   cmake . -DCMAKE_INSTALL_PREFIX=/path
+   make
+   make install

 As when using the simple configure method described above, "/path" points to
 the installation directory where you want to put the libpng "lib", "include",
@@ -122,8 +116,8 @@ or "zlib128") so that you have directories called "zlib" and "libpng".

 Your directory structure should look like this:

-    .. (the parent directory)
-      libpng (this directory)
+   ..       (the parent directory)
+      libpng  (this directory)
          INSTALL (this file)
          README
          *.h, *.c  => libpng source files
@@ -166,15 +160,10 @@ VII. Building with makefiles
 Copy the file (or files) that you need from the
 scripts directory into this directory, for example

-MSDOS example:
-
-    copy scripts\makefile.msc makefile
-    copy scripts\pnglibconf.h.prebuilt pnglibconf.h
-
-UNIX example:
-
-    cp scripts/makefile.std makefile
-    cp scripts/pnglibconf.h.prebuilt pnglibconf.h
+   MSDOS example: copy scripts\makefile.msc makefile
+                  copy scripts\pnglibconf.h.prebuilt pnglibconf.h
+   UNIX example:  cp scripts/makefile.std makefile
+                  cp scripts/pnglibconf.h.prebuilt pnglibconf.h

 Read the makefile to see if you need to change any source or
 target directories to match your preferences.
@@ -250,7 +239,7 @@ libpng are compiled.  All the defines end in _SUPPORTED.  If you are
 never going to use a capability, you can change the #define to #undef
 before recompiling libpng and save yourself code and data space, or
 you can turn off individual capabilities with defines that begin with
-"PNG_NO_".
+PNG_NO_.

 In libpng-1.5.0 and later, the #define's are in pnglibconf.h instead.

@@ -282,57 +271,7 @@ library to fail if they call functions not available in your library.
 The size of the library itself should not be an issue, because only
 those sections that are actually used will be loaded into memory.

-XIV. Enabling or disabling hardware optimizations
-
-Certain hardware capabilites, such as the Intel SSE instructions,
-are normally detected at run time. Enable them with configure options
-such as one of
-
-   --enable-arm-neon=yes
-   --enable-mips-msa=yes
-   --enable-intel-sse=yes
-   --enable-powerpc-vsx=yes
-
-or enable them all at once with
-
-   --enable-hardware-optimizations=yes
-
-or, if you are not using "configure", you can use one
-or more of
-
-   CPPFLAGS += "-DPNG_ARM_NEON"
-   CPPFLAGS += "-DPNG_MIPS_MSA"
-   CPPFLAGS += "-DPNG_INTEL_SSE"
-   CPPFLAGS += "-DPNG_POWERPC_VSX"
-
-See for example scripts/makefile.linux-opt
-
-If you wish to avoid using them,
-you can disable them via the configure option
-
-   --disable-hardware-optimizations
-
-to disable them all, or
-
-   --enable-intel-sse=no
-
-to disable a particular one,
-or via compiler-command options such as
-
-   CPPFLAGS += "-DPNG_ARM_NEON_OPT=0, -DPNG_MIPS_MSA_OPT=0,
-   -DPNG_INTEL_SSE_OPT=0, -DPNG_POWERPC_VSX_OPT=0"
-
-If you are using cmake, hardware optimizations are "on"
-by default. To disable them, use
-
-    cmake . -DPNG_ARM_NEON=no -DPNG_INTEL_SSE=no \
-            -DPNG_MIPS_MSA=no -DPNG_POWERPC_VSX=no
-
-or disable them all at once with
-
-    cmake . -DPNG_HARDWARE_OPTIMIZATIONS=no
-
-XV. Changes to the build and configuration of libpng in libpng-1.5.x
+XIV. Changes to the build and configuration of libpng in libpng-1.5.x

 Details of internal changes to the library code can be found in the CHANGES
 file and in the GIT repository logs.  These will be of no concern to the vast
@@ -368,7 +307,7 @@ only png_longjmp_ptr, which must match the C longjmp function.)  The new
 approach is documented in pngconf.h

 Despite these changes, libpng 1.5.0 only supports the native C function
-calling standard on those platforms tested so far ("__cdecl" on Microsoft
+calling standard on those platforms tested so far (__cdecl on Microsoft
 Windows).  This is because the support requirements for alternative
 calling conventions seem to no longer exist.  Developers who find it
 necessary to set PNG_API_RULE to 1 should advise the mailing list
@@ -423,7 +362,7 @@ $PREFIX/include directory).  Do not edit pnglibconf.h after you have built
 libpng, because than the settings would not accurately reflect the settings
 that were used to build libpng.

-XVI. Setjmp/longjmp issues
+XV. Setjmp/longjmp issues

 Libpng uses setjmp()/longjmp() for error handling.  Unfortunately setjmp()
 is known to be not thread-safe on some platforms and we don't know of
@@ -432,7 +371,7 @@ your application is going to be using multiple threads, you should
 configure libpng with PNG_NO_SETJMP in your pngusr.dfa file, with
 -DPNG_NO_SETJMP on your compile line, or with

-    #undef PNG_SETJMP_SUPPORTED
+  #undef PNG_SETJMP_SUPPORTED

 in your pnglibconf.h or pngusr.h.

@@ -441,25 +380,28 @@ This requires setjmp/longjmp, so you must either build the library
 with PNG_SETJMP_SUPPORTED defined, or with PNG_SIMPLIFIED_READ_SUPPORTED
 and PNG_SIMPLIFIED_WRITE_SUPPORTED undefined.

-XVII. Common linking failures
-
-If your application fails to find libpng or zlib entries while linking:
-
-  Be sure "-lz" appears after "-lpng" on your linking command.
-
-  Be sure you have built libpng, zlib, and your application for the
-  same platform (e.g., 32-bit or 64-bit).
-
-  If you are using the vstudio project, observe the WARNING in
-  project/vstudio/README.txt.
-
-XVIII. Other sources of information about libpng:
+XVI. Other sources of information about libpng:

 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.

-Copyright (c) 1998-2002,2006-2016 Glenn Randers-Pehrson
-This document is released under the libpng license.
-For conditions of distribution and use, see the disclaimer
-and license in png.h.
+Using the ./configure script -- 16 December 2002.
+=================================================
+
+The ./configure script should work compatibly with what scripts/makefile.*
+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 -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/libpng16, 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.
+
--- a/84
+++ b/84
@@ -10,21 +10,21 @@ this sentence.

 This code is released under the libpng license.

-libpng versions 1.0.7, July 1, 2000 through 1.6.34, September 29, 2017 are
-Copyright (c) 2000-2002, 2004, 2006-2017 Glenn Randers-Pehrson, are
-derived from libpng-1.0.6, and are distributed according to the same
-disclaimer and license as libpng-1.0.6 with the following individuals
-added to the list of Contributing Authors:
+libpng versions 1.2.6, August 15, 2004, through 1.6.17, March 26, 2015, are
+Copyright (c) 2004, 2006-2015 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
+
+   Cosmin Truta
+
+libpng versions 1.0.7, July 1, 2000, through 1.2.5 - October 3, 2002, are
+Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are
+distributed according to the same disclaimer and license as libpng-1.0.6
+with the following individuals added to the list of Contributing Authors

   Simon-Pierre Cadieux
   Eric S. Raymond
-   Mans Rullgard
-   Cosmin Truta
   Gilles Vollant
-   James Yu
-   Mandar Sahastrabuddhe
-   Google Inc.
-   Vadim Barkov

 and with the following additions to the disclaimer:

@@ -35,25 +35,19 @@ and with the following additions to the disclaimer:
   risk of satisfactory quality, performance, accuracy, and effort is with
   the user.

-Some files in the "contrib" directory and some configure-generated
-files that are distributed with libpng have other copyright owners and
-are released under other open source licenses.
-
 libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
-Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
-libpng-0.96, and are distributed according to the same disclaimer and
-license as libpng-0.96, with the following individuals added to the list
-of Contributing Authors:
+Copyright (c) 1998, 1999 Glenn Randers-Pehrson, and are
+distributed according to the same disclaimer and license as libpng-0.96,
+with the following individuals added to the list of Contributing Authors:

   Tom Lane
   Glenn Randers-Pehrson
   Willem van Schaik

 libpng versions 0.89, June 1996, through 0.96, May 1997, are
-Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88,
-and are distributed according to the same disclaimer and license as
-libpng-0.88, with the following individuals added to the list of
-Contributing Authors:
+Copyright (c) 1996, 1997 Andreas Dilger
+Distributed according to the same disclaimer and license as libpng-0.88,
+with the following individuals added to the list of Contributing Authors:

   John Bowler
   Kevin Bracey
@@ -62,11 +56,8 @@ Contributing Authors:
   Greg Roelofs
   Tom Tanner

-Some files in the "scripts" directory have other copyright owners
-but are released under this license.
-
 libpng versions 0.5, May 1995, through 0.88, January 1996, are
-Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
+Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.

 For the purposes of this copyright and license, "Contributing Authors"
 is defined as the following set of individuals:
@@ -89,13 +80,13 @@ Permission is hereby granted to use, copy, modify, and distribute this
 source code, or portions hereof, for any purpose, without fee, subject
 to the following restrictions:

-  1. The origin of this source code must not be misrepresented.
+1. The origin of this source code must not be misrepresented.

-  2. Altered versions must be plainly marked as such and must not
-     be misrepresented as being the original source.
+2. Altered versions must be plainly marked as such and must not
+   be misrepresented as being the original source.

-  3. This Copyright notice may not be removed or altered from any
-     source or altered source distribution.
+3. This Copyright notice may not be removed or altered from any
+   source or altered source distribution.

 The Contributing Authors and Group 42, Inc. specifically permit, without
 fee, and encourage the use of this source code as a component to
@@ -103,31 +94,18 @@ supporting the PNG file format in commercial products.  If you use this
 source code in a product, acknowledgment is not required but would be
 appreciated.

-END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE.

-TRADEMARK:
+A "png_get_copyright" function is available, for convenient use in "about"
+boxes and the like:

-The name "libpng" has not been registered by the Copyright owner
-as a trademark in any jurisdiction.  However, because libpng has
-been distributed and maintained world-wide, continually since 1995,
-the Copyright owner claims "common-law trademark protection" in any
-jurisdiction where common-law trademark is recognized.
+   printf("%s",png_get_copyright(NULL));

-OSI CERTIFICATION:
+Also, the PNG logo (in PNG format, of course) is supplied in the
+files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).

-Libpng is OSI Certified Open Source Software.  OSI Certified Open Source is
-a certification mark of the Open Source Initiative. OSI has not addressed
-the additional disclaimers inserted at version 1.0.7.
-
-EXPORT CONTROL:
-
-The Copyright owner believes that the Export Control Classification
-Number (ECCN) for libpng is EAR99, which means not subject to export
-controls or International Traffic in Arms Regulations (ITAR) because
-it is open source, publicly available software, that does not contain
-any encryption software.  See the EAR, paragraphs 734.3(b)(3) and
-734.7(b).
+Libpng is OSI Certified Open Source Software.  OSI Certified Open Source is a
+certification mark of the Open Source Initiative.

 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-September 29, 2017
+March 26, 2015
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,21 +1,13 @@
-# Makefile.am, the source file for Makefile.in (and hence Makefile), is
+# Makefile.am:
+#   Source file for Makefile.in (and hence Makefile)
 #
-# Copyright (c) 2004-2016 Glenn Randers-Pehrson
-# Last changed in libpng 1.6.25 [September 1, 2016]
-#
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h

 PNGLIB_BASENAME= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@

 ACLOCAL_AMFLAGS = -I scripts

 # test programs - run on make check, make distcheck
-check_PROGRAMS= pngtest pngunknown pngstest pngvalid pngimage pngcp
-if HAVE_CLOCK_GETTIME
-check_PROGRAMS += timepng
-endif
+check_PROGRAMS= pngtest pngunknown pngstest pngvalid pngimage

 # Utilities - installed
 bin_PROGRAMS= pngfix png-fix-itxt
@@ -45,38 +37,37 @@ pngunknown_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 pngimage_SOURCES = contrib/libtests/pngimage.c
 pngimage_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la

-timepng_SOURCES = contrib/libtests/timepng.c
-timepng_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-
 pngfix_SOURCES = contrib/tools/pngfix.c
 pngfix_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la

 png_fix_itxt_SOURCES = contrib/tools/png-fix-itxt.c

-pngcp_SOURCES = contrib/tools/pngcp.c
-pngcp_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-
 # Generally these are single line shell scripts to run a test with a particular
 # set of parameters:
 TESTS =\
   tests/pngtest\
-   tests/pngtest-badpngs\
   tests/pngvalid-gamma-16-to-8 tests/pngvalid-gamma-alpha-mode\
   tests/pngvalid-gamma-background tests/pngvalid-gamma-expand16-alpha-mode\
   tests/pngvalid-gamma-expand16-background\
   tests/pngvalid-gamma-expand16-transform tests/pngvalid-gamma-sbit\
   tests/pngvalid-gamma-threshold tests/pngvalid-gamma-transform\
-   tests/pngvalid-progressive-size\
+   tests/pngvalid-progressive-interlace-size\
   tests/pngvalid-progressive-interlace-standard\
-   tests/pngvalid-transform\
+   tests/pngvalid-progressive-interlace-transform\
   tests/pngvalid-progressive-standard tests/pngvalid-standard\
-   tests/pngstest-1.8 tests/pngstest-1.8-alpha tests/pngstest-linear\
-   tests/pngstest-linear-alpha tests/pngstest-none tests/pngstest-none-alpha\
-   tests/pngstest-sRGB tests/pngstest-sRGB-alpha tests/pngunknown-IDAT\
+   tests/pngstest-0g01 tests/pngstest-0g02 tests/pngstest-0g04\
+   tests/pngstest-0g08 tests/pngstest-0g16 tests/pngstest-2c08\
+   tests/pngstest-2c16 tests/pngstest-3p01 tests/pngstest-3p02\
+   tests/pngstest-3p04 tests/pngstest-3p08 tests/pngstest-4a08\
+   tests/pngstest-4a16 tests/pngstest-6a08 tests/pngstest-6a16\
+   tests/pngstest-error tests/pngunknown-IDAT\
   tests/pngunknown-discard tests/pngunknown-if-safe tests/pngunknown-sAPI\
   tests/pngunknown-sTER tests/pngunknown-save tests/pngunknown-vpAg\
   tests/pngimage-quick tests/pngimage-full

+# These tests are expected, and required, to fail:
+XFAIL_TESTS = tests/pngstest-error
+
 # man pages
 dist_man_MANS= libpng.3 libpngpf.3 png.5

@@ -98,21 +89,6 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += arm/arm_init.c\
 	arm/filter_neon.S arm/filter_neon_intrinsics.c
 endif

-if PNG_MIPS_MSA
-libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += mips/mips_init.c\
-	mips/filter_msa_intrinsics.c
-endif
-
-if PNG_INTEL_SSE
-libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += intel/intel_init.c\
-	intel/filter_sse2_intrinsics.c
-endif
-
-if PNG_POWERPC_VSX
-libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += powerpc/powerpc_init.c\
-        powerpc/filter_vsx_intrinsics.c
-endif
-
 nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h

 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS = -no-undefined -export-dynamic \
@@ -249,7 +225,6 @@ contrib/libtests/timepng.o: pnglibconf.h

 contrib/tools/makesRGB.o: pnglibconf.h
 contrib/tools/pngfix.o: pnglibconf.h
-contrib/tools/pngcp.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
--- a/21
+++ b/21
@@ -1,4 +1,4 @@
-README for libpng version 1.6.34 - September 29, 2017 (shared library 16.0)
+README for libpng version 1.6.17 - March 26, 2015 (shared library 16.0)
 See the note about version numbers near the top of png.h

 See INSTALL for instructions on how to install libpng.
@@ -23,7 +23,7 @@ earlier versions if you are using a shared library.  The type of the
 png_uint_32, which will affect shared-library applications that use
 this function.

-To avoid problems with changes to the internals of the png info_struct,
+To avoid problems with changes to the internals of png info_struct,
 new APIs have been made available in 0.95 to avoid direct application
 access to info_ptr.  These functions are the png_set_<chunk> and
 png_get_<chunk> functions.  These functions should be used when
@@ -88,11 +88,11 @@ zlib should be available at the same place that libpng is, or at zlib.net.

 You may also want a copy of the PNG specification.  It is available
 as an RFC, a W3C Recommendation, and an ISO/IEC Standard.  You can find
-these at http://www.libpng.org/pub/png/pngdocs.html .
+these at http://www.libpng.org/pub/png/documents/

-This code is currently being archived at libpng.sourceforge.io in the
-[DOWNLOAD] area, and at http://libpng.download/src .  If you
-can't find it in any of those places, e-mail me, and I'll help you find it.
+This code is currently being archived at libpng.sf.net in the
+[DOWNLOAD] area, and at ftp://ftp.simplesystems.org.  If you can't find it
+in any of those places, e-mail me, and I'll help you find it.

 I am not a lawyer, but I believe that the Export Control Classification
 Number (ECCN) for libpng is EAR99, which means not subject to export
@@ -134,7 +134,7 @@ 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 twenty years now, and it is official and
+been discussing PNG for nineteen 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.
@@ -179,25 +179,18 @@ Files in this distribution:
      pngwtran.c    =>  Write data transformations
      pngwutil.c    =>  Write utility functions
      arm           =>  Contains optimized code for the ARM platform
-      powerpc       =>  Contains optimized code for the PowerPC platform
      contrib       =>  Contributions
-       arm-neon         =>  Optimized code for ARM-NEON platform
-       powerpc-vsx      =>  Optimized code for POWERPC-VSX platform
       examples         =>  Example programs
       gregbook         =>  source code for PNG reading and writing, from
                            Greg Roelofs' "PNG: The Definitive Guide",
                            O'Reilly, 1999
       libtests         =>  Test programs
-       mips-msa         =>  Optimized code for MIPS-MSA platform
       pngminim         =>  Minimal decoder, encoder, and progressive decoder
                            programs demonstrating use of pngusr.dfa
       pngminus         =>  Simple pnm2png and png2pnm programs
       pngsuite         =>  Test images
-       testpngs
       tools            =>  Various tools
       visupng          =>  Contains a MSVC workspace for VisualPng
-      intel             =>  Optimized code for INTEL-SSE2 platform
-      mips              =>  Optimized code for MIPS platform
      projects      =>  Contains project files and workspaces for
                        building a DLL
       owatcom          =>  Contains a WATCOM project for building libpng
--- a/7
+++ b/7
@@ -5,14 +5,13 @@ Final bug fixes.
 Better C++ wrapper/full C++ implementation?
 Fix problem with C++ and EXTERN "C".
 cHRM transformation.
-Remove setjmp/longjmp usage in favor of returning error codes. As a start on
-  this, minimize the use of png_error(), replacing them with
-  png_warning(); return(0); or similar.
+Remove setjmp/longjmp usage in favor of returning error codes.
 Palette creation.
 Add "grayscale->palette" transformation and "palette->grayscale" detection.
 Improved dithering.
 Multi-lingual error and warning message support.
 Complete sRGB transformation (presently it simply uses gamma=0.45455).
+Make profile checking optional via a png_set_something() call.
 Man pages for function calls.
 Better documentation.
 Better filter selection
@@ -24,7 +23,7 @@ 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.
-Refactor preprocessor conditionals to compile entire statements

 */
--- a/arm/arm_init.c
+++ b/arm/arm_init.c
@@ -1,9 +1,9 @@

 /* arm_init.c - NEON optimised filter functions
 *
- * Copyright (c) 2014,2016 Glenn Randers-Pehrson
+ * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.6.22 [May 26, 2016]
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -66,7 +66,6 @@ png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
    * wrong order of the 'ON' and 'default' cases.  UNSET now defaults to OFF,
    * as documented in png.h
    */
-   png_debug(1, "in png_init_filter_functions_neon");
 #ifdef PNG_ARM_NEON_API_SUPPORTED
   switch ((pp->options >> PNG_ARM_NEON) & 3)
   {
--- a/arm/filter_neon.S
+++ b/arm/filter_neon.S
@@ -1,9 +1,9 @@

 /* filter_neon.S - NEON optimised filter functions
 *
- * Copyright (c) 2014,2017 Glenn Randers-Pehrson
+ * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.6.31 [July 27, 2017]
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -16,7 +16,7 @@
 #define PNG_VERSION_INFO_ONLY
 #include "../pngpriv.h"

-#if (defined(__linux__) || defined(__FreeBSD__)) && defined(__ELF__)
+#if defined(__linux__) && defined(__ELF__)
 .section .note.GNU-stack,"",%progbits /* mark stack as non-executable */
 #endif

--- a/arm/filter_neon_intrinsics.c
+++ b/arm/filter_neon_intrinsics.c
@@ -1,11 +1,11 @@

 /* filter_neon_intrinsics.c - NEON optimised filter functions
 *
- * Copyright (c) 2014,2016 Glenn Randers-Pehrson
+ * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by James Yu <james.yu at linaro.org>, October 2013.
 * Based on filter_neon.S, written by Mans Rullgard, 2011.
 *
- * Last changed in libpng 1.6.22 [May 26, 2016]
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -47,8 +47,6 @@ png_read_filter_row_up_neon(png_row_infop row_info, png_bytep row,
   png_bytep rp_stop = row + row_info->rowbytes;
   png_const_bytep pp = prev_row;

-   png_debug(1, "in png_read_filter_row_up_neon");
-
   for (; rp < rp_stop; rp += 16, pp += 16)
   {
      uint8x16_t qrp, qpp;
@@ -74,8 +72,6 @@ png_read_filter_row_sub3_neon(png_row_infop row_info, png_bytep row,
   uint8x8x4_t vdest;
   vdest.val[3] = vdup_n_u8(0);

-   png_debug(1, "in png_read_filter_row_sub3_neon");
-
   for (; rp < rp_stop;)
   {
      uint8x8_t vtmp1, vtmp2;
@@ -117,8 +113,6 @@ png_read_filter_row_sub4_neon(png_row_infop row_info, png_bytep row,
   uint8x8x4_t vdest;
   vdest.val[3] = vdup_n_u8(0);

-   png_debug(1, "in png_read_filter_row_sub4_neon");
-
   for (; rp < rp_stop; rp += 16)
   {
      uint32x2x4_t vtmp = vld4_u32(png_ptr(uint32_t,rp));
@@ -154,8 +148,6 @@ png_read_filter_row_avg3_neon(png_row_infop row_info, png_bytep row,
   vrpt = png_ptr(uint8x8x2_t,&vtmp);
   vrp = *vrpt;

-   png_debug(1, "in png_read_filter_row_avg3_neon");
-
   for (; rp < rp_stop; pp += 12)
   {
      uint8x8_t vtmp1, vtmp2, vtmp3;
@@ -215,8 +207,6 @@ png_read_filter_row_avg4_neon(png_row_infop row_info, png_bytep row,
   uint8x8x4_t vdest;
   vdest.val[3] = vdup_n_u8(0);

-   png_debug(1, "in png_read_filter_row_avg4_neon");
-
   for (; rp < rp_stop; rp += 16, pp += 16)
   {
      uint32x2x4_t vtmp;
@@ -290,8 +280,6 @@ png_read_filter_row_paeth3_neon(png_row_infop row_info, png_bytep row,
   vrpt = png_ptr(uint8x8x2_t,&vtmp);
   vrp = *vrpt;

-   png_debug(1, "in png_read_filter_row_paeth3_neon");
-
   for (; rp < rp_stop; pp += 12)
   {
      uint8x8x2_t *vppt;
@@ -351,8 +339,6 @@ png_read_filter_row_paeth4_neon(png_row_infop row_info, png_bytep row,
   uint8x8x4_t vdest;
   vdest.val[3] = vdup_n_u8(0);

-   png_debug(1, "in png_read_filter_row_paeth4_neon");
-
   for (; rp < rp_stop; rp += 16, pp += 16)
   {
      uint32x2x4_t vtmp;
--- a/autogen.sh
+++ b/autogen.sh
@@ -73,13 +73,12 @@ done
 # 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"
+libpng_autotools_files="Makefile.in aclocal.m4 config.guess config.h.in\
+   config.sub configure depcomp install-sh ltmain.sh missing test-driver"
 #
 # Files generated by versions of configue >2.68 or automake >1.13 (i.e. later
 # versions than those required by configure.ac):
-libpng_autotools_extra="compile config.h.in~"
+libpng_autotools_extra="compile"
 #
 # These are separate because 'maintainer-clean' does not remove them.
 libpng_libtool_files="scripts/libtool.m4 scripts/ltoptions.m4\
--- a/configure.ac
+++ b/configure.ac
@@ -1,12 +1,5 @@
 # configure.ac

-# Copyright (c) 2004-2016 Glenn Randers-Pehrson
-# Last changed in libpng 1.6.25 [September 1, 2016]
-
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
-
 dnl Process this file with autoconf to produce a configure script.
 dnl
 dnl Minor upgrades (compatible ABI): increment the package version
@@ -25,7 +18,7 @@ AC_PREREQ([2.68])

 dnl Version number stuff here:

-AC_INIT([libpng],[1.6.34],[png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng],[1.6.17],[png-mng-implement@lists.sourceforge.net])
 AC_CONFIG_MACRO_DIR([scripts])

 # libpng does not follow GNU file name conventions (hence 'foreign')
@@ -36,7 +29,7 @@ AC_CONFIG_MACRO_DIR([scripts])
 # 1.13 is required for parallel tests
 AM_INIT_AUTOMAKE([1.13 foreign dist-xz color-tests silent-rules subdir-objects])
 # The following line causes --disable-maintainer-mode to be the default to
-# configure. This is necessary because libpng distributions cannot rely on the
+# configure, this is necessary because libpng distributions cannot rely on the
 # time stamps of the autotools generated files being correct
 AM_MAINTAINER_MODE

@@ -46,10 +39,10 @@ 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=1.6.34
+PNGLIB_VERSION=1.6.17
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=6
-PNGLIB_RELEASE=34
+PNGLIB_RELEASE=17

 dnl End of version number stuff

@@ -67,7 +60,7 @@ AC_PROG_INSTALL
 AC_PROG_LN_S
 AC_PROG_MAKE_SET

-dnl libtool/libtoolize; version 2.4.2 is the tested version. This or any
+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])
@@ -114,25 +107,6 @@ AC_ARG_ENABLE(werror,
      CFLAGS="$sav_CFLAGS"
    fi],)

-# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89
-# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining _POSIX_SOURCE to 1
-# This is incompatible with the new default mode, so we test for that and force the 
-# "-std=c89" compiler option:
-AC_MSG_CHECKING([if we need to force back C standard to C89])
-AC_COMPILE_IFELSE(
-   [AC_LANG_PROGRAM([
-      [#define _POSIX_SOURCE 1]
-      [#include <stdio.h>]
-   ])],
-   AC_MSG_RESULT(no),[
-      if test "x$GCC" != "xyes"; then
-         AC_MSG_ERROR(
-            [Forcing back to C89 is required but the flags are only known for GCC])
-      fi
-   AC_MSG_RESULT(yes)
-   CFLAGS="$CFLAGS -std=c89"
-])
-
 # Checks for header files.
 AC_HEADER_STDC

@@ -146,12 +120,6 @@ AC_C_RESTRICT
 AC_FUNC_STRTOD
 AC_CHECK_FUNCS([memset], , AC_MSG_ERROR(memset not found in libc))
 AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_MSG_ERROR(cannot find pow)) )
-
-# Some later POSIX 1003.1 functions are required for test programs, failure here
-# is soft (the corresponding test program is not built).
-AC_CHECK_FUNC([clock_gettime],,[AC_MSG_WARN([not building timepng])])
-AM_CONDITIONAL([HAVE_CLOCK_GETTIME], [test "$ac_cv_func_clock_gettime" = "yes"])
-
 AC_ARG_WITH(zlib-prefix,
   AS_HELP_STRING([[[--with-zlib-prefix]]],
      [prefix that may have been used in installed zlib]),
@@ -300,55 +268,6 @@ AM_CONDITIONAL([DO_INSTALL_LIBPNG_CONFIG],
 # HOST SPECIFIC OPTIONS
 # =====================
 #
-# DEFAULT
-# =======
-#
-AC_ARG_ENABLE([hardware-optimizations],
-   AS_HELP_STRING([[[--enable-hardware-optimizations]]],
-      [Enable hardware optimizations: =no/off, yes/on:]),
-   [case "$enableval" in
-      no|off)
-         # disable hardware optimization on all systems:
-         enable_arm_neon=no
-         AC_DEFINE([PNG_ARM_NEON_OPT], [0],
-           [Disable ARM_NEON optimizations])
-         enable_mips_msa=no
-         AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
-           [Disable MIPS_MSA optimizations])
-         enable_powerpc_vsx=no
-         AC_DEFINE([PNG_POWERPC_VSX_OPT], [0],
-           [Disable POWERPC VSX optimizations])
-         enable_intel_sse=no
-         AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
-           [Disable INTEL_SSE optimizations])
-         ;;
-      *)
-         # allow enabling hardware optimization on any system:
-         case "$host_cpu" in
-            arm*|aarch64*)
-              enable_arm_neon=yes
-              AC_DEFINE([PNG_ARM_NEON_OPT], [0],
-                [Enable ARM_NEON optimizations])
-              ;;
-            mipsel*|mips64el*)
-              enable_mips_msa=yes
-              AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
-                [Enable MIPS_MSA optimizations])
-              ;;
-            i?86|x86_64)
-              enable_intel_sse=yes
-              AC_DEFINE([PNG_INTEL_SSE_OPT], [1],
-                [Enable Intel SSE optimizations])
-              ;;
-            powerpc*|ppc64*)
-              enable_powerpc_vsx=yes
-              AC_DEFINE([PNG_POWERPC_VSX_OPT], [2],
-                [Enable POWERPC VSX optimizations])
-              ;;
-         esac
-         ;;
-   esac])
-
 # ARM
 # ===
 #
@@ -395,134 +314,6 @@ AM_CONDITIONAL([PNG_ARM_NEON],
      *)    test "$enable_arm_neon" != '';;
    esac])

-# MIPS
-# ===
-#
-# MIPS MSA (SIMD) support.
-
-AC_ARG_ENABLE([mips-msa],
-   AS_HELP_STRING([[[--enable-mips-msa]]],
-      [Enable MIPS MSA optimizations: =no/off, check, api, yes/on:]
-      [no/off: disable the optimizations; check: use internal checking code]
-      [(deprecated and poorly supported); api: disable by default, enable by]
-      [a call to png_set_option; yes/on: turn on unconditionally.]
-      [If not specified: determined by the compiler.]),
-   [case "$enableval" in
-      no|off)
-         # disable the default enabling on __mips_msa systems:
-         AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
-                   [Disable MIPS MSA optimizations])
-         # Prevent inclusion of the assembler files below:
-         enable_mips_msa=no;;
-      check)
-         AC_DEFINE([PNG_MIPS_MSA_CHECK_SUPPORTED], [],
-                   [Check for MIPS MSA support at run-time]);;
-      api)
-         AC_DEFINE([PNG_MIPS_MSA_API_SUPPORTED], [],
-                   [Turn on MIPS MSA optimizations at run-time]);;
-      yes|on)
-         AC_DEFINE([PNG_MIPS_MSA_OPT], [2],
-                   [Enable MIPS MSA optimizations])
-         AC_MSG_WARN([--enable-mips-msa: please specify 'check' or 'api', if]
-            [you want the optimizations unconditionally pass '-mmsa -mfp64']
-            [to the compiler.]);;
-      *)
-         AC_MSG_ERROR([--enable-mips-msa=${enable_mips_msa}: invalid value])
-   esac])
-
-# Add MIPS specific files to all builds where the host_cpu is mips ('mips*') or
-# where MIPS optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'mips*')
-
-AM_CONDITIONAL([PNG_MIPS_MSA],
-   [test "$enable_mips_msa" != 'no' &&
-    case "$host_cpu" in
-      mipsel*|mips64el*) :;;
-    esac])
-
-# INTEL
-# =====
-#
-# INTEL SSE (SIMD) support.
-
-AC_ARG_ENABLE([intel-sse],
-   AS_HELP_STRING([[[--enable-intel-sse]]],
-      [Enable Intel SSE optimizations: =no/off, yes/on:]
-      [no/off: disable the optimizations;]
-      [yes/on: enable the optimizations.]
-      [If not specified: determined by the compiler.]),
-   [case "$enableval" in
-      no|off)
-         # disable the default enabling:
-         AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
-                   [Disable Intel SSE optimizations])
-         # Prevent inclusion of the assembler files below:
-         enable_intel_sse=no;;
-      yes|on)
-         AC_DEFINE([PNG_INTEL_SSE_OPT], [1],
-                   [Enable Intel SSE optimizations]);;
-      *)
-         AC_MSG_ERROR([--enable-intel-sse=${enable_intel_sse}: invalid value])
-   esac])
-
-# Add Intel specific files to all builds where the host_cpu is Intel ('x86*')
-# or where Intel optimizations were explicitly requested (this allows a
-# fallback if a future host CPU does not match 'x86*')
-AM_CONDITIONAL([PNG_INTEL_SSE],
-   [test "$enable_intel_sse" != 'no' &&
-    case "$host_cpu" in
-      i?86|x86_64) :;;
-      *)    test "$enable_intel_sse" != '';;
-    esac])
-
-# PowerPC
-# ===
-#
-# PowerPC VSX (SIMD) support.
-
-AC_ARG_ENABLE([powerpc-vsx],
-AS_HELP_STRING([[[--enable-powerpc-vsx]]],
-      [Enable POWERPC VSX optimizations: =no/off, check, api, yes/on:]
-      [no/off: disable the optimizations; check: use internal checking code]
-      [api: disable by default, enable by a call to png_set_option]
-      [yes/on: turn on unconditionally.]
-      [If not specified: determined by the compiler.]),
-   [case "$enableval" in
-      no|off)
-         # disable the default enabling on __ppc64__ systems:
-         AC_DEFINE([PNG_POWERPC_VSX_OPT], [0],
-                   [Disable POWERPC VSX optimizations])
-         # Prevent inclusion of the platform specific files below:
-         enable_powerpc_vsx=no;;
-      check)
-         AC_DEFINE([PNG_POWERPC_VSX_CHECK_SUPPORTED], [],
-                   [Check for POWERPC VSX support at run-time])
-         AC_MSG_WARN([--enable-powerpc-vsx Please check contrib/powerpc/README file]
-            [for the list of supported OSes.]);;
-      api)
-         AC_DEFINE([PNG_POWERPC_VSX_API_SUPPORTED], [],
-                   [Turn on POWERPC VSX optimizations at run-time]);;
-      yes|on)
-         AC_DEFINE([PNG_POWERPC_VSX_OPT], [2],
-                   [Enable POWERPC VSX optimizations])
-         AC_MSG_WARN([--enable-powerpc-vsx: please specify 'check' or 'api', if]
-            [you want the optimizations unconditionally pass '-maltivec -mvsx']
-            [or '-mcpu=power8'to the compiler.]);;
-      *)
-         AC_MSG_ERROR([--enable-powerpc-vsx=${enable_powerpc_vsx}: invalid value])
-   esac])
-
-# Add PowerPC specific files to all builds where the host_cpu is powerpc('powerpc*') or
-# where POWERPC optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'powerpc*')
-
-AM_CONDITIONAL([PNG_POWERPC_VSX],
-   [test "$enable_powerpc_vsx" != 'no' &&
-    case "$host_cpu" in
-      powerpc*|ppc64*) :;;
-    esac])
-
-
 AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])

 # Config files, substituting as above
--- a/contrib/README.txt
+++ b/contrib/README.txt
@@ -1,5 +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, although some are used
-for testing the library via "make check".
+libpng proper and are not used for building the library.
--- a/contrib/arm-neon/README
+++ b/contrib/arm-neon/README
@@ -1,7 +1,7 @@
 OPERATING SYSTEM SPECIFIC ARM NEON DETECTION
 --------------------------------------------

-Detection of the ability to execute ARM NEON on an ARM processor requires
+Detection of the ability to exexcute ARM NEON on an ARM processor requires
 operating system support.  (The information is not available in user mode.)

 HOW TO USE THIS
--- a/contrib/arm-neon/android-ndk.c
+++ b/contrib/arm-neon/android-ndk.c
@@ -17,7 +17,7 @@
 *
 * Documentation:
 *    http://www.kandroid.org/ndk/docs/CPU-ARM-NEON.html
- *    https://code.google.com/p/android/issues/detail?id=49065
+ *    http://code.google.com/p/android/issues/detail?id=49065
 *
 * NOTE: this requires that libpng is built against the Android NDK and linked
 * with an implementation of the Android ARM 'cpu-features' library.  The code
--- a/contrib/arm-neon/linux-auxv.c
+++ b/contrib/arm-neon/linux-auxv.c
@@ -7,7 +7,7 @@
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
 * and license in png.h
- *
+ * 
 * SEE contrib/arm-neon/README before reporting bugs
 *
 * STATUS: COMPILED, TESTED
--- a/contrib/arm-neon/linux.c
+++ b/contrib/arm-neon/linux.c
@@ -1,8 +1,8 @@
 /* contrib/arm-neon/linux.c
 *
- * Last changed in libpng 1.6.31 [July 27, 2017]
- * Copyright (c) 2014, 2017 Glenn Randers-Pehrson
- * Written by John Bowler, 2014, 2017.
+ * Copyright (c) 2014 Glenn Randers-Pehrson
+ * Written by John Bowler, 2014.
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -62,7 +62,7 @@ png_have_neon(png_structp png_ptr)

               counter=0;
               state = Feature;
-               /* FALLTHROUGH */
+               /* FALL THROUGH */

            case Feature:
               /* Match 'FEATURE', ASCII case insensitive. */
@@ -72,10 +72,10 @@ png_have_neon(png_structp png_ptr)
                     state = Colon;
                  break;
               }
-
+               
               /* did not match 'feature' */
               state = SkipLine;
-               /* FALLTHROUGH */
+               /* FALL THROUGH */

            case SkipLine:
            skipLine:
@@ -110,7 +110,7 @@ png_have_neon(png_structp png_ptr)

               state = Neon;
               counter = 0;
-               /* FALLTHROUGH */
+               /* FALL THROUGH */

            case Neon:
               /* Look for 'neon' tag */
@@ -122,7 +122,7 @@ png_have_neon(png_structp png_ptr)
               }

               state = SkipTag;
-               /* FALLTHROUGH */
+               /* FALL THROUGH */

            case SkipTag:
               /* Skip non-space characters */
--- a/contrib/conftest/pngcp.dfa
+++ b/contrib/conftest/pngcp.dfa
@@ -1,57 +0,0 @@
-# pngcp.dfa
-#  Build time configuration of libpng
-#
-# Author: John Bowler
-# Copyright: (c) John Bowler, 2016
-# Usage rights:
-#  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.
-#
-# Build libpng with support for pngcp.  This means just png_read_png,
-# png_write_png and small number of configuration settings.
-#
-everything = off
-
-# This option is specific to this configuration; it adds a #define to the
-# generated pnglibconf.h which turns on the (not portable) timing option for
-# pngcp.  Note that any option is automatically preceded by PNG_; there is no
-# way round this and this is deliberate.
-option PNGCP_TIMING
-
-# Because of the everything off above the option must also be turned on.  This
-# may not be done in one step because it is safer and avoids mis-spelled options
-# in user .dfa files to error out if an unrecognized option is turned on.
-option PNGCP_TIMING on
-
-# Options to turn on png_read_png and png_write_png:
-option INFO_IMAGE on
-option SEQUENTIAL_READ on
-option EASY_ACCESS on
-option WRITE on
-option WRITE_16BIT on
-option WRITE_FILTER on
-
-# pngcp needs this to preserve unknown chunks, switching all these on means that
-# pngcp can work without explicit known chunk reading suppport
-option UNKNOWN_CHUNKS on
-option SET_UNKNOWN_CHUNKS on
-option HANDLE_AS_UNKNOWN on
-option SAVE_UNKNOWN_CHUNKS on
-option WRITE_UNKNOWN_CHUNKS on
-
-# pngcp needs this to handle palette files with invalid indices:
-option CHECK_FOR_INVALID_INDEX on
-option GET_PALETTE_MAX on
-
-# Pre-libpng 1.7 pngcp has to stash text chunks manually, post 1.7 without this
-# text chunks should be handled as unknown ok.
-option TEXT on
-
-# this is used to turn off limits:
-option USER_LIMITS on
-option SET_USER_LIMITS on
-
-# these are are just required for specific customizations
-option WRITE_CUSTOMIZE_ZTXT_COMPRESSION on
-option WRITE_CUSTOMIZE_COMPRESSION on
--- a/contrib/examples/README.txt
+++ b/contrib/examples/README.txt
@@ -21,4 +21,4 @@ ORIGINAL AUTHORS
    of the people below claim any rights with regard to the contents of this
    directory.

-    John Bowler <jbowler at acm.org>
+    John Bowler <jbowler@acm.org>
--- a/contrib/examples/iccfrompng.c
+++ b/contrib/examples/iccfrompng.c
@@ -26,10 +26,6 @@

 #include <png.h>

-#if defined(PNG_READ_SUPPORTED) && defined(PNG_STDIO_SUPPORTED) && \
-    defined (PNG_iCCP_SUPPORTED)
-
-
 static int verbose = 1;
 static png_byte no_profile[] = "no profile";

@@ -182,4 +178,3 @@ main(int argc, char **argv)
   /* Exit code is true if any extract succeeds */
   return extracted == 0;
 }
-#endif /* READ && STDIO && iCCP */
--- a/contrib/examples/pngpixel.c
+++ b/contrib/examples/pngpixel.c
@@ -27,8 +27,6 @@
 */
 #include "../../png.h"

-#if defined(PNG_READ_SUPPORTED) && defined(PNG_SEQUENTIAL_READ_SUPPORTED)
-
 /* 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,
@@ -87,7 +85,7 @@ print_pixel(png_structp png_ptr, png_infop info_ptr, png_const_bytep row,
       */
      case PNG_COLOR_TYPE_PALETTE:
         {
-            PNG_CONST int index = component(row, x, 0, bit_depth, 1);
+            PNG_CONST unsigned int index = component(row, x, 0, bit_depth, 1);
            png_colorp palette = NULL;
            int num_palette = 0;

@@ -368,4 +366,3 @@ int main(int argc, const char **argv)

   return result;
 }
-#endif /* READ && SEQUENTIAL_READ */
--- a/contrib/examples/pngtopng.c
+++ b/contrib/examples/pngtopng.c
@@ -1,12 +1,10 @@
 /*- pngtopng
 *
- * COPYRIGHT: Written by John Cunningham Bowler, 2011, 2017.
+ * 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.
 *
- * Last changed in libpng 1.6.29 [March 16, 2017]
- *
 * Read a PNG and write it out in a fixed format, using the 'simplified API'
 * that was introduced in libpng-1.6.0.
 *
@@ -22,8 +20,6 @@
 * ensure the code picks up the local libpng implementation:
 */
 #include "../../png.h"
-#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) && \
-    defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)

 int main(int argc, const char **argv)
 {
@@ -61,27 +57,26 @@ int main(int argc, const char **argv)
               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);

-            free(buffer);
+               /* 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));
-
-            /* 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 and so libpng
-             * has not got to the point where it can do cleanup.
-             */
-            png_image_free(&image);
-         }
      }

      else
@@ -95,4 +90,3 @@ int main(int argc, const char **argv)

   return result;
 }
-#endif /* READ && WRITE */
--- a/contrib/examples/simpleover.c
+++ b/contrib/examples/simpleover.c
@@ -1,648 +0,0 @@
-/*- simpleover
- *
- * COPYRIGHT: Written by John Cunningham Bowler, 2015.
- * 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 several PNG files, which should have an alpha channel or transparency
- * information, and composite them together to produce one or more 16-bit linear
- * RGBA intermediates.  This involves doing the correct 'over' composition to
- * combine the alpha channels and corresponding data.
- *
- * Finally read an output (background) PNG using the 24-bit RGB format (the
- * PNG will be composited on green (#00ff00) by default if it has an alpha
- * channel), and apply the intermediate image generated above to specified
- * locations in the image.
- *
- * The command line has the general format:
- *
- *    simpleover <background.png> [output.png]
- *        {--sprite=width,height,name {[--at=x,y] {sprite.png}}}
- *        {--add=name {x,y}}
- *
- * The --sprite and --add options may occur multiple times. They are executed
- * in order.  --add may refer to any sprite already read.
- *
- * This code is intended to show how to composite multiple images together
- * correctly.  Apart from the libpng Simplified API the only work done in here
- * is to combine multiple input PNG images into a single sprite; this involves
- * a Porter-Duff 'over' operation and the input PNG images may, as a result,
- * be regarded as being layered one on top of the other with the first (leftmost
- * on the command line) being at the bottom and the last on the top.
- */
-#include <stddef.h>
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-#include <errno.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, so long as this
- * file is linked against a sufficiently recent libpng (1.6+) it is ok to
- * change this to <png.h>:
- */
-#include "../../png.h"
-
-#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
-
-#define sprite_name_chars 15
-struct sprite {
-   FILE         *file;
-   png_uint_16p  buffer;
-   unsigned int  width;
-   unsigned int  height;
-   char          name[sprite_name_chars+1];
-};
-
-#if 0 /* div by 65535 test program */
-#include <math.h>
-#include <stdio.h>
-
-int main(void) {
-   double err = 0;
-   unsigned int xerr = 0;
-   unsigned int r = 32769;
-   {
-      unsigned int x = 0;
-
-      do {
-         unsigned int t = x + (x >> 16) /*+ (x >> 31)*/ + r;
-         double v = x, errtest;
-
-         if (t < x) {
-            fprintf(stderr, "overflow: %u+%u -> %u\n", x, r, t);
-            return 1;
-         }
-
-         v /= 65535;
-         errtest = v;
-         t >>= 16;
-         errtest -= t;
-
-         if (errtest > err) {
-            err = errtest;
-            xerr = x;
-
-            if (errtest >= .5) {
-               fprintf(stderr, "error: %u/65535 = %f, not %u, error %f\n",
-                     x, v, t, errtest);
-               return 0;
-            }
-         }
-      } while (++x <= 65535U*65535U);
-   }
-
-   printf("error %f @ %u\n", err, xerr);
-
-   return 0;
-}
-#endif /* div by 65535 test program */
-
-static void
-sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
-   png_imagep image, const png_uint_16 *buffer)
-{
-   /* This is where the Porter-Duff 'Over' operator is evaluated; change this
-    * code to change the operator (this could be parameterized).  Any other
-    * image processing operation could be used here.
-    */
-
-
-   /* Check for an x or y offset that pushes any part of the image beyond the
-    * right or bottom of the sprite:
-    */
-   if ((y_offset < 0 || (unsigned)/*SAFE*/y_offset < sprite->height) &&
-       (x_offset < 0 || (unsigned)/*SAFE*/x_offset < sprite->width))
-   {
-      unsigned int y = 0;
-
-      if (y_offset < 0)
-         y = -y_offset; /* Skip to first visible row */
-
-      do
-      {
-         unsigned int x = 0;
-
-         if (x_offset < 0)
-            x = -x_offset;
-
-         do
-         {
-            /* In and out are RGBA values, so: */
-            const png_uint_16 *in_pixel = buffer + (y * image->width + x)*4;
-            png_uint_32 in_alpha = in_pixel[3];
-
-            /* This is the optimized Porter-Duff 'Over' operation, when the
-             * input alpha is 0 the output is not changed.
-             */
-            if (in_alpha > 0)
-            {
-               png_uint_16 *out_pixel = sprite->buffer +
-                  ((y+y_offset) * sprite->width + (x+x_offset))*4;
-
-               /* This is the weight to apply to the output: */
-               in_alpha = 65535-in_alpha;
-
-               if (in_alpha > 0)
-               {
-                  /* The input must be composed onto the output. This means
-                   * multiplying the current output pixel value by the inverse
-                   * of the input alpha (1-alpha). A division is required but
-                   * it is by the constant 65535.  Approximate this as:
-                   *
-                   *     (x + (x >> 16) + 32769) >> 16;
-                   *
-                   * This is exact (and does not overflow) for all values of
-                   * x in the range 0..65535*65535.  (Note that the calculation
-                   * produces the closest integer; the maximum error is <0.5).
-                   */
-                  png_uint_32 tmp;
-
-#                 define compose(c)\
-                     tmp = out_pixel[c] * in_alpha;\
-                     tmp = (tmp + (tmp >> 16) + 32769) >> 16;\
-                     out_pixel[c] = tmp + in_pixel[c]
-
-                  /* The following is very vectorizable... */
-                  compose(0);
-                  compose(1);
-                  compose(2);
-                  compose(3);
-               }
-
-               else
-                  out_pixel[0] = in_pixel[0],
-                  out_pixel[1] = in_pixel[1],
-                  out_pixel[2] = in_pixel[2],
-                  out_pixel[3] = in_pixel[3];
-            }
-         }
-         while (++x < image->width);
-      }
-      while (++y < image->height);
-   }
-}
-
-static int
-create_sprite(struct sprite *sprite, int *argc, const char ***argv)
-{
-   /* Read the arguments and create this sprite. The sprite buffer has already
-    * been allocated. This reads the input PNGs one by one in linear format,
-    * composes them onto the sprite buffer (the code in the function above)
-    * then saves the result, converting it on the fly to PNG RGBA 8-bit format.
-    */
-   while (*argc > 0)
-   {
-      char tombstone;
-      int x = 0, y = 0;
-
-      if ((*argv)[0][0] == '-' && (*argv)[0][1] == '-')
-      {
-         /* The only supported option is --at. */
-         if (sscanf((*argv)[0], "--at=%d,%d%c", &x, &y, &tombstone) != 2)
-            break; /* success; caller will parse this option */
-
-         ++*argv, --*argc;
-      }
-
-      else
-      {
-         /* The argument has to be a file name */
-         png_image image;
-
-         image.version = PNG_IMAGE_VERSION;
-         image.opaque = NULL;
-
-         if (png_image_begin_read_from_file(&image, (*argv)[0]))
-         {
-            png_uint_16p buffer;
-
-            image.format = PNG_FORMAT_LINEAR_RGB_ALPHA;
-
-            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*/))
-               {
-                  /* This is the place where the Porter-Duff 'Over' operator
-                   * needs to be done by this code.  In fact, any image
-                   * processing required can be done here; the data is in
-                   * the correct format (linear, 16-bit) and source and
-                   * destination are in memory.
-                   */
-                  sprite_op(sprite, x, y, &image, buffer);
-                  free(buffer);
-                  ++*argv, --*argc;
-                  /* And continue to the next argument */
-                  continue;
-               }
-
-               else
-               {
-                  free(buffer);
-                  fprintf(stderr, "simpleover: read %s: %s\n", (*argv)[0],
-                      image.message);
-               }
-            }
-
-            else
-            {
-               fprintf(stderr, "simpleover: out of memory: %lu bytes\n",
-                  (unsigned long)PNG_IMAGE_SIZE(image));
-
-               /* png_image_free must be called if we abort the Simplified API
-                * read because of a problem detected in this code.  If problems
-                * are detected in the Simplified API it cleans up itself.
-                */
-               png_image_free(&image);
-            }
-         }
-
-         else
-         {
-            /* Failed to read the first argument: */
-            fprintf(stderr, "simpleover: %s: %s\n", (*argv)[0], image.message);
-         }
-
-         return 0; /* failure */
-      }
-   }
-
-   /* All the sprite operations have completed successfully. Save the RGBA
-    * buffer as a PNG using the simplified write API.
-    */
-   sprite->file = tmpfile();
-
-   if (sprite->file != NULL)
-   {
-      png_image save;
-
-      memset(&save, 0, sizeof save);
-      save.version = PNG_IMAGE_VERSION;
-      save.opaque = NULL;
-      save.width = sprite->width;
-      save.height = sprite->height;
-      save.format = PNG_FORMAT_LINEAR_RGB_ALPHA;
-      save.flags = PNG_IMAGE_FLAG_FAST;
-      save.colormap_entries = 0;
-
-      if (png_image_write_to_stdio(&save, sprite->file, 1/*convert_to_8_bit*/,
-          sprite->buffer, 0/*row_stride*/, NULL/*colormap*/))
-      {
-         /* Success; the buffer is no longer needed: */
-         free(sprite->buffer);
-         sprite->buffer = NULL;
-         return 1; /* ok */
-      }
-
-      else
-         fprintf(stderr, "simpleover: write sprite %s: %s\n", sprite->name,
-            save.message);
-   }
-
-   else
-      fprintf(stderr, "simpleover: sprite %s: could not allocate tmpfile: %s\n",
-         sprite->name, strerror(errno));
-
-   return 0; /* fail */
-}
-
-static int
-add_sprite(png_imagep output, png_bytep out_buf, struct sprite *sprite,
-   int *argc, const char ***argv)
-{
-   /* Given a --add argument naming this sprite, perform the operations listed
-    * in the following arguments.  The arguments are expected to have the form
-    * (x,y), which is just an offset at which to add the sprite to the
-    * output.
-    */
-   while (*argc > 0)
-   {
-      char tombstone;
-      int x, y;
-
-      if ((*argv)[0][0] == '-' && (*argv)[0][1] == '-')
-         return 1; /* success */
-
-      if (sscanf((*argv)[0], "%d,%d%c", &x, &y, &tombstone) == 2)
-      {
-         /* Now add the new image into the sprite data, but only if it
-          * will fit.
-          */
-         if (x < 0 || y < 0 ||
-             (unsigned)/*SAFE*/x >= output->width ||
-             (unsigned)/*SAFE*/y >= output->height ||
-             sprite->width > output->width-x ||
-             sprite->height > output->height-y)
-         {
-            fprintf(stderr, "simpleover: sprite %s @ (%d,%d) outside image\n",
-               sprite->name, x, y);
-            /* Could just skip this, but for the moment it is an error */
-            return 0; /* error */
-         }
-
-         else
-         {
-            /* Since we know the sprite fits we can just read it into the
-             * output using the simplified API.
-             */
-            png_image in;
-
-            in.version = PNG_IMAGE_VERSION;
-            rewind(sprite->file);
-
-            if (png_image_begin_read_from_stdio(&in, sprite->file))
-            {
-               in.format = PNG_FORMAT_RGB; /* force compose */
-
-               if (png_image_finish_read(&in, NULL/*background*/,
-                  out_buf + (y*output->width + x)*3/*RGB*/,
-                  output->width*3/*row_stride*/,
-                  NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP*/))
-               {
-                  ++*argv, --*argc;
-                  continue;
-               }
-            }
-
-            /* The read failed: */
-            fprintf(stderr, "simpleover: add sprite %s: %s\n", sprite->name,
-                in.message);
-            return 0; /* error */
-         }
-      }
-
-      else
-      {
-         fprintf(stderr, "simpleover: --add='%s': invalid position %s\n",
-               sprite->name, (*argv)[0]);
-         return 0; /* error */
-      }
-   }
-
-   return 1; /* ok */
-}
-
-static int
-simpleover_process(png_imagep output, png_bytep out_buf, int argc,
-   const char **argv)
-{
-   int result = 1; /* success */
-#  define csprites 10/*limit*/
-#  define str(a) #a
-   int nsprites = 0;
-   struct sprite sprites[csprites];
-
-   while (argc > 0)
-   {
-      result = 0; /* fail */
-
-      if (strncmp(argv[0], "--sprite=", 9) == 0)
-      {
-         char tombstone;
-
-         if (nsprites < csprites)
-         {
-            int n;
-
-            sprites[nsprites].width = sprites[nsprites].height = 0;
-            sprites[nsprites].name[0] = 0;
-
-            n = sscanf(argv[0], "--sprite=%u,%u,%" str(sprite_name_chars) "s%c",
-                &sprites[nsprites].width, &sprites[nsprites].height,
-                sprites[nsprites].name, &tombstone);
-
-            if ((n == 2 || n == 3) &&
-                sprites[nsprites].width > 0 && sprites[nsprites].height > 0)
-            {
-               size_t buf_size, tmp;
-
-               /* Default a name if not given. */
-               if (sprites[nsprites].name[0] == 0)
-                  sprintf(sprites[nsprites].name, "sprite-%d", nsprites+1);
-
-               /* Allocate a buffer for the sprite and calculate the buffer
-                * size:
-                */
-               buf_size = sizeof (png_uint_16 [4]);
-               buf_size *= sprites[nsprites].width;
-               buf_size *= sprites[nsprites].height;
-
-               /* This can overflow a (size_t); check for this: */
-               tmp = buf_size;
-               tmp /= sprites[nsprites].width;
-               tmp /= sprites[nsprites].height;
-
-               if (tmp == sizeof (png_uint_16 [4]))
-               {
-                  sprites[nsprites].buffer = malloc(buf_size);
-                  /* This buffer must be initialized to transparent: */
-                  memset(sprites[nsprites].buffer, 0, buf_size);
-
-                  if (sprites[nsprites].buffer != NULL)
-                  {
-                     sprites[nsprites].file = NULL;
-                     ++argv, --argc;
-
-                     if (create_sprite(sprites+nsprites++, &argc, &argv))
-                     {
-                        result = 1; /* still ok */
-                        continue;
-                     }
-
-                     break; /* error */
-                  }
-               }
-
-               /* Overflow, or OOM */
-               fprintf(stderr, "simpleover: %s: sprite too large\n", argv[0]);
-               break;
-            }
-
-            else
-            {
-               fprintf(stderr, "simpleover: %s: invalid sprite (%u,%u)\n",
-                  argv[0], sprites[nsprites].width, sprites[nsprites].height);
-               break;
-            }
-         }
-
-         else
-         {
-            fprintf(stderr, "simpleover: %s: too many sprites\n", argv[0]);
-            break;
-         }
-      }
-
-      else if (strncmp(argv[0], "--add=", 6) == 0)
-      {
-         const char *name = argv[0]+6;
-         int isprite = nsprites;
-
-         ++argv, --argc;
-
-         while (--isprite >= 0)
-         {
-            if (strcmp(sprites[isprite].name, name) == 0)
-            {
-               if (!add_sprite(output, out_buf, sprites+isprite, &argc, &argv))
-                  goto out; /* error in add_sprite */
-
-               break;
-            }
-         }
-
-         if (isprite < 0) /* sprite not found */
-         {
-            fprintf(stderr, "simpleover: --add='%s': sprite not found\n", name);
-            break;
-         }
-      }
-
-      else
-      {
-         fprintf(stderr, "simpleover: %s: unrecognized operation\n", argv[0]);
-         break;
-      }
-
-      result = 1; /* ok  */
-   }
-
-   /* Clean up the cache of sprites: */
-out:
-   while (--nsprites >= 0)
-   {
-      if (sprites[nsprites].buffer != NULL)
-         free(sprites[nsprites].buffer);
-
-      if (sprites[nsprites].file != NULL)
-         (void)fclose(sprites[nsprites].file);
-   }
-
-   return result;
-}
-
-int main(int argc, const char **argv)
-{
-   int result = 1; /* default to fail */
-
-   if (argc >= 2)
-   {
-      int argi = 2;
-      const char *output = NULL;
-      png_image image;
-
-      if (argc > 2 && argv[2][0] != '-'/*an operation*/)
-      {
-         output = argv[2];
-         argi = 3;
-      }
-
-      image.version = PNG_IMAGE_VERSION;
-      image.opaque = NULL;
-
-      if (png_image_begin_read_from_file(&image, argv[1]))
-      {
-         png_bytep buffer;
-
-         image.format = PNG_FORMAT_RGB; /* 24-bit RGB */
-
-         buffer = malloc(PNG_IMAGE_SIZE(image));
-
-         if (buffer != NULL)
-         {
-            png_color background = {0, 0xff, 0}; /* fully saturated green */
-
-            if (png_image_finish_read(&image, &background, buffer,
-               0/*row_stride*/, NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP */))
-            {
-               /* At this point png_image_finish_read has cleaned up the
-                * allocated data in png_image, and only the buffer needs to be
-                * freed.
-                *
-                * Perform the remaining operations:
-                */
-               if (simpleover_process(&image, buffer, argc-argi, argv+argi))
-               {
-                  /* Write the output: */
-                  if ((output != NULL &&
-                       png_image_write_to_file(&image, output,
-                        0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
-                        NULL/*colormap*/)) ||
-                      (output == NULL &&
-                       png_image_write_to_stdio(&image, stdout,
-                        0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
-                        NULL/*colormap*/)))
-                     result = 0;
-
-                  else
-                     fprintf(stderr, "simpleover: write %s: %s\n",
-                        output == NULL ? "stdout" : output, image.message);
-               }
-
-               /* else simpleover_process writes an error message */
-            }
-
-            else
-               fprintf(stderr, "simpleover: read %s: %s\n", argv[1],
-                   image.message);
-
-            free(buffer);
-         }
-
-         else
-         {
-            fprintf(stderr, "simpleover: out of memory: %lu bytes\n",
-               (unsigned long)PNG_IMAGE_SIZE(image));
-
-            /* 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
-      {
-         /* Failed to read the first argument: */
-         fprintf(stderr, "simpleover: %s: %s\n", argv[1], image.message);
-      }
-   }
-
-   else
-   {
-      /* Usage message */
-      fprintf(stderr,
-         "simpleover: usage: simpleover background.png [output.png]\n"
-         "  Output 'background.png' as a 24-bit RGB PNG file in 'output.png'\n"
-         "   or, if not given, stdout.  'background.png' will be composited\n"
-         "   on fully saturated green.\n"
-         "\n"
-         "  Optionally, before output, process additional PNG files:\n"
-         "\n"
-         "   --sprite=width,height,name {[--at=x,y] {sprite.png}}\n"
-         "    Produce a transparent sprite of size (width,height) and with\n"
-         "     name 'name'.\n"
-         "    For each sprite.png composite it using a Porter-Duff 'Over'\n"
-         "     operation at offset (x,y) in the sprite (defaulting to (0,0)).\n"
-         "     Input PNGs will be truncated to the area of the sprite.\n"
-         "\n"
-         "   --add='name' {x,y}\n"
-         "    Optionally, before output, composite a sprite, 'name', which\n"
-         "     must have been previously produced using --sprite, at each\n"
-         "     offset (x,y) in the output image.  Each sprite must fit\n"
-         "     completely within the output image.\n"
-         "\n"
-         "  PNG files are processed in the order they occur on the command\n"
-         "  line and thus the first PNG processed appears as the bottommost\n"
-         "  in the output image.\n");
-   }
-
-   return result;
-}
-#endif /* SIMPLIFIED_READ */
--- a/contrib/gregbook/README
+++ b/contrib/gregbook/README
@@ -15,7 +15,7 @@ of PBMPLUS/NetPBM) and converts them to PNG.

 The source code for all three demo programs currently compiles under
 Unix, OpenVMS, and 32-bit Windows.  (Special thanks to Martin Zinser,
-zinser at decus.de, for making the necessary changes for OpenVMS and for
+zinser@decus.de, for making the necessary changes for OpenVMS and for
 providing an appropriate build script.)  Build instructions can be found
 below.

@@ -55,7 +55,7 @@ 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
-https://pobox.com/~newt/greg_contact.html
+http://pobox.com/~newt/greg_contact.html
 16 March 2008


@@ -63,7 +63,7 @@ BUILD INSTRUCTIONS

 - Prerequisites (in order of compilation):

-      - zlib            https://zlib.net/
+      - zlib            http://zlib.net/
      - libpng          http://www.libpng.org/pub/png/libpng.html
      - pngbook         http://www.libpng.org/pub/png/book/sources.html

--- a/contrib/gregbook/readpng.c
+++ b/contrib/gregbook/readpng.c
@@ -4,7 +4,7 @@

  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2007,2017 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
@@ -264,12 +264,6 @@ uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
    *pRowbytes = rowbytes = png_get_rowbytes(png_ptr, info_ptr);
    *pChannels = (int)png_get_channels(png_ptr, info_ptr);

-    /* Guard against integer overflow */
-    if (height > ((size_t)(-1))/rowbytes) {
-        fprintf(stderr, "readpng:  image_data buffer would be too large\n",
-        return NULL;
-    }
-
    if ((image_data = (uch *)malloc(rowbytes*height)) == NULL) {
        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
        return NULL;
--- a/contrib/gregbook/readpng2.c
+++ b/contrib/gregbook/readpng2.c
@@ -4,7 +4,7 @@

  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2015 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
@@ -51,12 +51,6 @@
      along with this program; if not, write to the Free Software Foundation,
      Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

-  ---------------------------------------------------------------------------
-
-   Changelog:
-     2015-11-12 - Check return value of png_get_bKGD() (Glenn R-P)
-     2017-04-22 - Guard against integer overflow (Glenn R-P)
-
  ---------------------------------------------------------------------------*/


@@ -267,38 +261,36 @@ static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)
    /* since we know we've read all of the PNG file's "header" (i.e., up
     * to IDAT), we can check for a background color here */

-    if (mainprog_ptr->need_bgcolor)
+    if (mainprog_ptr->need_bgcolor &&
+        png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))
    {
        png_color_16p pBackground;

        /* it is not obvious from the libpng documentation, but this function
         * takes a pointer to a pointer, and it always returns valid red,
         * green and blue values, regardless of color_type: */
-        if (png_get_bKGD(png_ptr, info_ptr, &pBackground))
-        {
+        png_get_bKGD(png_ptr, info_ptr, &pBackground);

-           /* however, it always returns the raw bKGD data, regardless of any
-            * bit-depth transformations, so check depth and adjust if necessary
-            */
-           if (bit_depth == 16) {
-               mainprog_ptr->bg_red   = pBackground->red   >> 8;
-               mainprog_ptr->bg_green = pBackground->green >> 8;
-               mainprog_ptr->bg_blue  = pBackground->blue  >> 8;
-           } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
-               if (bit_depth == 1)
-                   mainprog_ptr->bg_red = mainprog_ptr->bg_green =
-                     mainprog_ptr->bg_blue = pBackground->gray? 255 : 0;
-               else if (bit_depth == 2)
-                   mainprog_ptr->bg_red = mainprog_ptr->bg_green =
-                     mainprog_ptr->bg_blue = (255/3) * pBackground->gray;
-               else /* bit_depth == 4 */
-                   mainprog_ptr->bg_red = mainprog_ptr->bg_green =
-                     mainprog_ptr->bg_blue = (255/15) * pBackground->gray;
-           } else {
-               mainprog_ptr->bg_red   = (uch)pBackground->red;
-               mainprog_ptr->bg_green = (uch)pBackground->green;
-               mainprog_ptr->bg_blue  = (uch)pBackground->blue;
-           }
+        /* however, it always returns the raw bKGD data, regardless of any
+         * bit-depth transformations, so check depth and adjust if necessary */
+        if (bit_depth == 16) {
+            mainprog_ptr->bg_red   = pBackground->red   >> 8;
+            mainprog_ptr->bg_green = pBackground->green >> 8;
+            mainprog_ptr->bg_blue  = pBackground->blue  >> 8;
+        } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+            if (bit_depth == 1)
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = pBackground->gray? 255 : 0;
+            else if (bit_depth == 2)
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = (255/3) * pBackground->gray;
+            else /* bit_depth == 4 */
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = (255/15) * pBackground->gray;
+        } else {
+            mainprog_ptr->bg_red   = (uch)pBackground->red;
+            mainprog_ptr->bg_green = (uch)pBackground->green;
+            mainprog_ptr->bg_blue  = (uch)pBackground->blue;
        }
    }

--- a/contrib/gregbook/readppm.c
+++ b/contrib/gregbook/readppm.c
@@ -9,7 +9,7 @@

  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2007,2017 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
@@ -154,18 +154,13 @@ uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
    *pRowbytes = rowbytes = channels*width;
    *pChannels = channels;

-    Trace((stderr, "readpng_get_image:  rowbytes = %ld, height = %ld\n", rowbytes, height));
-
-    /* Guard against integer overflow */
-    if (height > ((size_t)(-1))/rowbytes) {
-        fprintf(stderr, PROGNAME ":  image_data buffer would be too large\n",
-        return NULL;
-    }
-
    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 */

    if (fread(image_data, 1L, rowbytes*height, saved_infile) <
--- a/contrib/gregbook/rpng-win.c
+++ b/contrib/gregbook/rpng-win.c
@@ -24,11 +24,10 @@
    - 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)
-    - 2.02:  check for integer overflow (Glenn R-P)

  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2008, 2017 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
@@ -183,7 +182,7 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
 #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 at realviz.com for supplying the magical
+     * app.  Thanks to David.Geldreich@realviz.com for supplying the magical
     * incantation. */

    AllocConsole();
@@ -497,12 +496,6 @@ static int rpng_win_create_window(HINSTANCE hInst, int showmode)

    wimage_rowbytes = ((3*image_width + 3L) >> 2) << 2;

-    /* Guard against integer overflow */
-    if (image_height > ((size_t)(-1))/wimage_rowbytes) {
-        fprintf(stderr, PROGNAME ":  image_data buffer would be too large\n");
-        return 4;   /* fail */
-    }
-
    if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +
                              wimage_rowbytes*image_height)))
    {
--- a/contrib/gregbook/rpng-x.c
+++ b/contrib/gregbook/rpng-x.c
@@ -28,11 +28,10 @@
    - 2.01:  fixed improper display of usage screen on PNG error(s)
    - 2.02:  Added "void(argc);" statement to quiet pedantic compiler warnings
             about unused variable (GR-P)
-    - 2.03:  check for integer overflow (Glenn R-P)

  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2008, 2017 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
--- a/contrib/gregbook/rpng2-win.c
+++ b/contrib/gregbook/rpng2-win.c
@@ -33,11 +33,12 @@
    - 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
-    - 2.04:  check for integer overflow (Glenn R-P)
+    - 2.04:  
+             (GR-P)

  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2008, 2017 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
@@ -300,7 +301,7 @@ int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
 #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 at realviz.com for supplying the magical
+     * app.  Thanks to David.Geldreich@realviz.com for supplying the magical
     * incantation. */

    AllocConsole();
@@ -649,13 +650,6 @@ static void rpng2_win_init()
    Trace((stderr, "  width  = %ld\n", rpng2_info.width))
    Trace((stderr, "  height = %ld\n", rpng2_info.height))

-    /* Guard against integer overflow */
-    if (rpng2_info.height > ((size_t)(-1))/rowbytes) {
-        fprintf(stderr, PROGNAME ":  image_data buffer would be too large\n",
-        readpng2_cleanup(&rpng2_info);
-        return;
-    }
-
    rpng2_info.image_data = (uch *)malloc(rowbytes * rpng2_info.height);
    if (!rpng2_info.image_data) {
        readpng2_cleanup(&rpng2_info);
--- a/contrib/gregbook/rpng2-x.c
+++ b/contrib/gregbook/rpng2-x.c
@@ -43,12 +43,12 @@
    - 2.03:  deleted runtime MMX-enabling/disabling and obsolete -mmx* options
    - 2.04:  Added "void(foo);" statements to quiet pedantic compiler warnings
             about unused variables (GR-P)
-    - 2.05:  Use nanosleep() instead of usleep(), which is deprecated (GR-P).
-    - 2.06:  check for integer overflow (Glenn R-P)
+
+  TO DO:
+             use nanosleep() instead of usleep(), which is obsolete/deprecated.
  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2010, 2014-2015, 2017 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
@@ -119,7 +119,6 @@
 # undef usleep
 # define usleep(usec) {        \
   struct timespec ts;         \
-   ts.tv_sec = 0;              \
   ts.tv_nsec = (usec) * 1000; \
   nanosleep(&ts, NULL); }
 #  endif
@@ -498,12 +497,12 @@ int main(int argc, char **argv)
          "\t\t  transparent images; overrides -bgcolor\n",
          num_bgpat-1);
 #ifdef FEATURE_LOOP
-        fprintf(stderr,
+        fprintf(stderr, 
          "    -loop\tloops through background images after initial display\n"
          "\t\t  is complete (depends on -bgpat)\n"
          "    sec \tseconds to display each background image (default = 2)\n");
 #endif
-        fprintf(stderr,
+        fprintf(stderr, 
          "    dur \tduration in microseconds to wait after displaying each\n"
          "\t\t  row (for demo purposes)\n"
          "    -timing\tenables delay for every block read, to simulate modem\n"
@@ -782,13 +781,6 @@ static void rpng2_x_init(void)
    Trace((stderr, "  width  = %ld\n", rpng2_info.width))
    Trace((stderr, "  height = %ld\n", rpng2_info.height))

-    /* Guard against integer overflow */
-    if (rpng2_info.height > ((size_t)(-1))/rpng2_info.rowbytes) {
-        fprintf(stderr, PROGNAME ":  image_data buffer would be too large\n");
-        readpng2_cleanup(&rpng2_info);
-        return;
-    }
-
    rpng2_info.image_data = (uch *)malloc(rowbytes * rpng2_info.height);
    if (!rpng2_info.image_data) {
        readpng2_cleanup(&rpng2_info);
--- a/contrib/gregbook/wpng.c
+++ b/contrib/gregbook/wpng.c
@@ -29,7 +29,6 @@
    - 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)
-    - 2.01:  check for integer overflow (Glenn R-P)

        [REPORTED BUG (win32 only):  "contrib/gregbook/wpng.c - cmd line
         dose not work!  In order to do something useful I needed to redirect
@@ -39,7 +38,7 @@

  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2007, 2017 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
@@ -703,18 +702,7 @@ int main(int argc, char **argv)
    if (wpng_info.interlaced) {
        long i;
        ulg bytes;
-        ulg image_bytes;
-
-        /* Guard against integer overflow */
-        if (wpng_info_height > ((size_t)(-1)/rowbytes ||
-            wpng_info_height > ((ulg)(-1)/rowbytes) {
-            fprintf(stderr, PROGNAME ":  image_data buffer too large\n");
-            writepng_cleanup(&wpng_info);
-            wpng_cleanup();
-            exit(5);
-        }
-
-        image_bytes = rowbytes * wpng_info.height;
+        ulg image_bytes = rowbytes * wpng_info.height;   /* overflow? */

        wpng_info.image_data = (uch *)malloc(image_bytes);
        wpng_info.row_pointers = (uch **)malloc(wpng_info.height*sizeof(uch *));
--- a/contrib/gregbook/writepng.c
+++ b/contrib/gregbook/writepng.c
@@ -4,7 +4,7 @@

  ---------------------------------------------------------------------------

-      Copyright (c) 1998-2007, 2017 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
--- a/contrib/libtests/fakepng.c
+++ b/contrib/libtests/fakepng.c
@@ -1,12 +1,4 @@
-/* Fake a PNG - just write it out directly.
- *
- * COPYRIGHT: Written by John Cunningham Bowler, 2014.
- * 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.
- *
- */
-
+/* Fake a PNG - just write it out directly. */
 #include <stdio.h>
 #include <zlib.h> /* for crc32 */

--- a/contrib/libtests/makepng.c
+++ b/contrib/libtests/makepng.c
@@ -1,9 +1,8 @@
-/* makepng.c */
-#define _ISOC99_SOURCE
-/* Copyright: */
-#define COPYRIGHT "\251 2013,2015 John Cunningham Bowler"
-/*
- * Last changed in libpng 1.6.20 [November 24, 2015]
+/* makepng.c
+ *
+ * Copyright (c) 2013 John Cunningham Bowler
+ *
+ * Last changed in libpng 1.6.1 [March 28, 2013]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -11,8 +10,8 @@
 *
 * Make a test PNG image.  The arguments are as follows:
 *
- *    makepng [--sRGB|--linear|--1.8] [--tRNS] [--nofilters] \
- *       color-type bit-depth [file-name]
+ *  makepng [--sRGB|--linear|--1.8] [--color=<color>] color-type bit-depth \
+ *      [file-name]
 *
 * The color-type may be numeric (and must match the numbers used by the PNG
 * specification) or one of the format names listed below.  The bit-depth is the
@@ -40,8 +39,8 @@
 * 4 channels: linear combinations of, from the top-left corner clockwise,
 *    transparent, red, green, blue.
 *
- * For color-mapped images a four channel color-map is used and if --tRNS is
- * given the PNG file has a tRNS chunk, as follows:
+ * For color-mapped images a four channel color-map is used and the PNG file has
+ * a tRNS chunk, as follows:
 *
 * 1-bit: entry 0 is transparent-red, entry 1 is opaque-white
 * 2-bit: entry 0: transparent-green
@@ -54,9 +53,6 @@
 * The palette always has 2^bit-depth entries and the tRNS chunk one fewer.  The
 * image is the 1-channel diamond, but using palette index, not luminosity.
 *
- * For formats other than color-mapped ones if --tRNS is specified a tRNS chunk
- * is generated with all channels equal to the low bits of 0x0101.
- *
 * Image size is determined by the final pixel depth in bits, i.e. channels x
 * bit-depth, as follows:
 *
@@ -64,64 +60,20 @@
 * 16 bits:           256x256
 * More than 16 bits: 1024x1024
 *
- * Row filtering is the libpng default but may be turned off (the 'none' filter
- * is used on every row) with the --nofilters option.
- *
- * The images are not interlaced.
- *
- * If file-name is given then the PNG is written to that file, else it is
- * written to stdout.  Notice that stdout is not supported on systems where, by
- * default, it assumes text output; this program makes no attempt to change the
- * text mode of stdout!
- *
- *    makepng --color=<color> ...
+ * Row filtering is turned off (the 'none' filter is used on every row) and the
+ * images are not interlaced.
 *
 * If --color is given then the whole image has that color, color-mapped images
 * will have exactly one palette entry and all image files with be 16x16 in
 * size.  The color value is 1 to 4 decimal numbers as appropriate for the color
 * type.
 *
- *    makepng --small ...
- *
- * If --small is given the images are no larger than required to include every
- * possible pixel value for the format.
- *
- * For formats with pixels 8 bits or fewer in size the images consist of a
- * single row with 2^pixel-depth pixels, one of every possible value.
- *
- * For formats with 16-bit pixels a 256x256 image is generated containing every
- * possible pixel value.
- *
- * For larger pixel sizes a 256x256 image is generated where the first row
- * consists of each pixel that has identical byte values throughout the pixel
- * followed by rows where the byte values differ within the pixel.
- *
- * In all cases the pixel values are arranged in such a way that the SUB and UP
- * filters give byte sequences for maximal zlib compression.  By default (if
- * --nofilters is not given) the SUB filter is used on the first row and the UP
- * filter on all following rows.
- *
- * The --small option is meant to provide good test-case coverage, however the
- * images are not easy to examine visually.  Without the --small option the
- * images contain identical color values; the pixel values are adjusted
- * according to the gamma encoding with no gamma encoding being interpreted as
- * sRGB.
- *
- * LICENSING
- * =========
- *
- * This code is copyright of the authors, see the COPYRIGHT define above.  The
- * code is licensed as above, using the libpng license.  The code generates
- * images which are solely the product of the code; the options choose which of
- * the many possibilities to generate.  The images that result (but not the code
- * which generates them) are licensed as defined here:
- *
- * IMPORTANT: the COPYRIGHT #define must contain ISO-Latin-1 characters, the
- * IMAGE_LICENSING #define must contain UTF-8 characters.  The 'copyright'
- * symbol 0xA9U (\251) in ISO-Latin-1 encoding and 0xC20xA9 (\302\251) in UTF-8.
+ * If file-name is given then the PNG is written to that file, else it is
+ * written to stdout.  Notice that stdout is not supported on systems where, by
+ * default, it assumes text output; this program makes no attempt to change the
+ * text mode of stdout!
 */
-#define IMAGE_LICENSING "Dedicated to the public domain per Creative Commons "\
-    "license \"CC0 1.0\"; https://creativecommons.org/publicdomain/zero/1.0/"
+#define _ISOC99_SOURCE /* for strtoull */

 #include <stddef.h> /* for offsetof */
 #include <stdlib.h>
@@ -130,8 +82,6 @@
 #include <ctype.h>
 #include <math.h>
 #include <errno.h>
-#include <assert.h>
-#include <stdint.h>

 #if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
 #  include <config.h>
@@ -146,25 +96,6 @@
 #  include "../../png.h"
 #endif

-#include <zlib.h>
-
-/* Work round for GCC complaints about casting a (double) function result to
- * an unsigned:
- */
-static unsigned int
-flooru(double d)
-{
-   d = floor(d);
-   return (unsigned int)d;
-}
-
-static png_byte
-floorb(double d)
-{
-   d = floor(d);
-   return (png_byte)d;
-}
-
 /* This structure is used for inserting extra chunks (the --insert argument, not
 * documented above.)
 */
@@ -176,7 +107,7 @@ typedef struct chunk_insert
   png_charp            parameters[1];
 } chunk_insert;

-static unsigned int
+static int
 channels_of_type(int color_type)
 {
   if (color_type & PNG_COLOR_MASK_PALETTE)
@@ -197,15 +128,14 @@ channels_of_type(int color_type)
   }
 }

-static unsigned int
+static int
 pixel_depth_of_type(int color_type, int bit_depth)
 {
   return channels_of_type(color_type) * bit_depth;
 }

 static unsigned int
-image_size_of_type(int color_type, int bit_depth, unsigned int *colors,
-   int small)
+image_size_of_type(int color_type, int bit_depth, unsigned int *colors)
 {
   if (*colors)
      return 16;
@@ -214,16 +144,7 @@ image_size_of_type(int color_type, int bit_depth, unsigned int *colors,
   {
      int pixel_depth = pixel_depth_of_type(color_type, bit_depth);

-      if (small)
-      {
-         if (pixel_depth <= 8) /* there will be one row */
-            return 1 << pixel_depth;
-
-         else
-            return 256;
-      }
-
-      else if (pixel_depth < 8)
+      if (pixel_depth < 8)
         return 64;

      else if (pixel_depth > 16)
@@ -296,8 +217,7 @@ generate_palette(png_colorp palette, png_bytep trans, int bit_depth,
         else
         {
            unsigned int size = 1U << (bit_depth/2); /* 2, 4 or 16 */
-            unsigned int x, y;
-            volatile unsigned int ip = 0;
+            unsigned int x, y, ip;

            for (x=0; x<size; ++x) for (y=0; y<size; ++y)
            {
@@ -361,7 +281,7 @@ set_value(png_bytep row, size_t rowbytes, png_uint_32 x, unsigned int bit_depth,
               exit(1);

            case 16:
-               value = flooru(65535*pow(value/65535.,conv)+.5);
+               value = (unsigned int)floor(65535*pow(value/65535.,conv)+.5);
               *row++ = (png_byte)(value >> 8);
               *row = (png_byte)value;
               return;
@@ -386,148 +306,15 @@ set_value(png_bytep row, size_t rowbytes, png_uint_32 x, unsigned int bit_depth,
   }
 }

-static int /* filter mask for row */
+static void
 generate_row(png_bytep row, size_t rowbytes, unsigned int y, int color_type,
   int bit_depth, png_const_bytep gamma_table, double conv,
-   unsigned int *colors, int small)
+   unsigned int *colors)
 {
-   int filters = 0; /* file *MASK*, 0 means the default, not NONE */
-   png_uint_32 size_max =
-      image_size_of_type(color_type, bit_depth, colors, small)-1;
+   png_uint_32 size_max = image_size_of_type(color_type, bit_depth, colors)-1;
   png_uint_32 depth_max = (1U << bit_depth)-1; /* up to 65536 */

-   if (colors[0] == 0) if (small)
-   {
-      unsigned int pixel_depth = pixel_depth_of_type(color_type, bit_depth);
-
-      /* For pixel depths less than 16 generate a single row containing all the
-       * possible pixel values.  For 16 generate all 65536 byte pair
-       * combinations in a 256x256 pixel array.
-       */
-      switch (pixel_depth)
-      {
-         case 1:
-            assert(y == 0 && rowbytes == 1 && size_max == 1);
-            row[0] = 0x6CU; /* binary: 01101100, only top 2 bits used */
-            filters = PNG_FILTER_NONE;
-            break;
-
-         case 2:
-            assert(y == 0 && rowbytes == 1 && size_max == 3);
-            row[0] = 0x1BU; /* binary 00011011, all bits used */
-            filters = PNG_FILTER_NONE;
-            break;
-
-         case 4:
-            assert(y == 0 && rowbytes == 8 && size_max == 15);
-            row[0] = 0x01U;
-            row[1] = 0x23U; /* SUB gives 0x22U for all following bytes */
-            row[2] = 0x45U;
-            row[3] = 0x67U;
-            row[4] = 0x89U;
-            row[5] = 0xABU;
-            row[6] = 0xCDU;
-            row[7] = 0xEFU;
-            filters = PNG_FILTER_SUB;
-            break;
-
-         case 8:
-            /* The row will have all the pixel values in order starting with
-             * '1', the SUB filter will change every byte into '1' (including
-             * the last, which generates pixel value '0').  Since the SUB filter
-             * has value 1 this should result in maximum compression.
-             */
-            assert(y == 0 && rowbytes == 256 && size_max == 255);
-            for (;;)
-            {
-               row[size_max] = 0xFFU & (size_max+1);
-               if (size_max == 0)
-                  break;
-               --size_max;
-            }
-            filters = PNG_FILTER_SUB;
-            break;
-
-         case 16:
-            /* Rows are generated such that each row has a constant difference
-             * between the first and second byte of each pixel and so that the
-             * difference increases by 1 at each row.  The rows start with the
-             * first byte value of 0 and the value increases to 255 across the
-             * row.
-             *
-             * The difference starts at 1, so the first row is:
-             *
-             *     0 1 1 2 2 3 3 4 ... 254 255 255 0
-             *
-             * This means that running the SUB filter on the first row produces:
-             *
-             *   [SUB==1] 0 1 0 1 0 1...
-             *
-             * Then the difference is 2 on the next row, giving:
-             *
-             *    0 2 1 3 2 4 3 5 ... 254 0 255 1
-             *
-             * When the UP filter is run on this libpng produces:
-             *
-             *   [UP ==2] 0 1 0 1 0 1...
-             *
-             * And so on for all the remain rows to the final two * rows:
-             *
-             *    row 254: 0 255 1 0 2 1 3 2 4 3 ... 254 253 255 254
-             *    row 255: 0   0 1 1 2 2 3 3 4 4 ... 254 254 255 255
-             */
-            assert(rowbytes == 512 && size_max == 255);
-            for (;;)
-            {
-               row[2*size_max  ] = 0xFFU & size_max;
-               row[2*size_max+1] = 0xFFU & (size_max+y+1);
-               if (size_max == 0)
-                  break;
-               --size_max;
-            }
-            /* The first row must include PNG_FILTER_UP so that libpng knows we
-             * need to keep it for the following row:
-             */
-            filters = (y == 0 ? PNG_FILTER_SUB+PNG_FILTER_UP : PNG_FILTER_UP);
-            break;
-
-         case 24:
-         case 32:
-         case 48:
-         case 64:
-            /* The rows are filled by an alogorithm similar to the above, in the
-             * first row pixel bytes are all equal, increasing from 0 by 1 for
-             * each pixel.  In the second row the bytes within a pixel are
-             * incremented 1,3,5,7,... from the previous row byte.  Using an odd
-             * number ensures all the possible byte values are used.
-             */
-            assert(size_max == 255 && rowbytes == 256*(pixel_depth>>3));
-            pixel_depth >>= 3; /* now in bytes */
-            while (rowbytes > 0)
-            {
-               const size_t pixel_index = --rowbytes/pixel_depth;
-
-               if (y == 0)
-                  row[rowbytes] = 0xFFU & pixel_index;
-
-               else
-               {
-                  const size_t byte_offset =
-                     rowbytes - pixel_index * pixel_depth;
-
-                  row[rowbytes] =
-                     0xFFU & (pixel_index + (byte_offset * 2*y) + 1);
-               }
-            }
-            filters = (y == 0 ? PNG_FILTER_SUB+PNG_FILTER_UP : PNG_FILTER_UP);
-            break;
-
-         default:
-            assert(0/*NOT REACHED*/);
-      }
-   }
-
-   else switch (channels_of_type(color_type))
+   if (colors[0] == 0) switch (channels_of_type(color_type))
   {
   /* 1 channel: a square image with a diamond, the least luminous colors are on
    *    the edge of the image, the most luminous in the center.
@@ -739,8 +526,6 @@ generate_row(png_bytep row, size_t rowbytes, unsigned int y, int color_type,
         colors[0], channels_of_type(color_type));
      exit(1);
   }
-
-   return filters;
 }


@@ -769,7 +554,7 @@ makepng_error(png_structp png_ptr, png_const_charp message)
 static int /* 0 on success, else an error code */
 write_png(const char **name, FILE *fp, int color_type, int bit_depth,
   volatile png_fixed_point gamma, chunk_insert * volatile insert,
-   unsigned int filters, unsigned int *colors, int small, int tRNS)
+   unsigned int filters, unsigned int *colors)
 {
   png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
      name, makepng_error, makepng_warning);
@@ -796,15 +581,6 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,

   /* Allow benign errors so that we can write PNGs with errors */
   png_set_benign_errors(png_ptr, 1/*allowed*/);
-
-   /* Max out the text compression level in an attempt to make the license
-    * small.   If --small then do the same for the IDAT.
-    */
-   if (small)
-      png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);
-
-   png_set_text_compression_level(png_ptr, Z_BEST_COMPRESSION);
-
   png_init_io(png_ptr, fp);

   info_ptr = png_create_info_struct(png_ptr);
@@ -812,37 +588,11 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
      png_error(png_ptr, "OOM allocating info structure");

   {
-      const unsigned int size =
-         image_size_of_type(color_type, bit_depth, colors, small);
-      unsigned int ysize;
+      unsigned int size = image_size_of_type(color_type, bit_depth, colors);
      png_fixed_point real_gamma = 45455; /* For sRGB */
      png_byte gamma_table[256];
      double conv;

-      /* Normally images are square, but with 'small' we want to simply generate
-       * all the pixel values, or all that we reasonably can:
-       */
-      if (small)
-      {
-         const unsigned int pixel_depth =
-            pixel_depth_of_type(color_type, bit_depth);
-
-         if (pixel_depth <= 8U)
-         {
-            assert(size == (1U<<pixel_depth));
-            ysize = 1U;
-         }
-
-         else
-         {
-            assert(size == 256U);
-            ysize = 256U;
-         }
-      }
-
-      else
-         ysize = size;
-
      /* This function uses the libpng values used on read to carry extra
       * information about the gamma:
       */
@@ -875,13 +625,13 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
            gamma_table[0] = 0;

            for (i=1; i<255; ++i)
-               gamma_table[i] = floorb(pow(i/255.,conv) * 255 + .5);
+               gamma_table[i] = (png_byte)floor(pow(i/255.,conv) * 255 + .5);

            gamma_table[255] = 255;
         }
      }

-      png_set_IHDR(png_ptr, info_ptr, size, ysize, bit_depth, color_type,
+      png_set_IHDR(png_ptr, info_ptr, size, size, bit_depth, color_type,
         PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

      if (color_type & PNG_COLOR_MASK_PALETTE)
@@ -893,26 +643,14 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
         npalette = generate_palette(palette, trans, bit_depth, gamma_table,
            colors);
         png_set_PLTE(png_ptr, info_ptr, palette, npalette);
-
-         if (tRNS)
-            png_set_tRNS(png_ptr, info_ptr, trans, npalette-1,
-               NULL/*transparent color*/);
+         png_set_tRNS(png_ptr, info_ptr, trans, npalette-1,
+            NULL/*transparent color*/);

         /* Reset gamma_table to prevent the image rows being changed */
         for (npalette=0; npalette<256; ++npalette)
            gamma_table[npalette] = (png_byte)npalette;
      }

-      else if (tRNS)
-      {
-         png_color_16 col;
-
-         col.red = col.green = col.blue = col.gray =
-            0x0101U & ((1U<<bit_depth)-1U);
-         col.index = 0U;
-         png_set_tRNS(png_ptr, info_ptr, NULL/*trans*/, 1U, &col);
-      }
-
      if (gamma == PNG_DEFAULT_sRGB)
         png_set_sRGB(png_ptr, info_ptr, PNG_sRGB_INTENT_ABSOLUTE);

@@ -944,11 +682,7 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
      png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, filters);

      {
-#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
-            int passes = png_set_interlace_handling(png_ptr);
-#        else /* !WRITE_INTERLACING */
-            int passes = 1;
-#        endif /* !WRITE_INTERLACING */
+         int passes = png_set_interlace_handling(png_ptr);
         int pass;
         png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);

@@ -961,15 +695,10 @@ write_png(const char **name, FILE *fp, int color_type, int bit_depth,
         {
            unsigned int y;

-            for (y=0; y<ysize; ++y)
+            for (y=0; y<size; ++y)
            {
-               unsigned int row_filters =
-                  generate_row(row, rowbytes, y, color_type, bit_depth,
-                        gamma_table, conv, colors, small);
-
-               if (row_filters != 0 && filters == PNG_ALL_FILTERS)
-                  png_set_filter(png_ptr, PNG_FILTER_TYPE_BASE, row_filters);
-
+               generate_row(row, rowbytes, y, color_type, bit_depth,
+                  gamma_table, conv, colors);
               png_write_row(png_ptr, row);
            }
         }
@@ -1098,7 +827,7 @@ static png_size_t
 load_fake(png_charp param, png_bytepp profile)
 {
   char *endptr = NULL;
-   uint64_t size = strtoull(param, &endptr, 0/*base*/);
+   unsigned long long int size = strtoull(param, &endptr, 0/*base*/);

   /* The 'fake' format is <number>*[string] */
   if (endptr != NULL && *endptr == '*')
@@ -1333,8 +1062,7 @@ insert_iTXt(png_structp png_ptr, png_infop info_ptr, int nparams,
 }

 static void
-insert_hIST(png_structp png_ptr, png_infop info_ptr, int nparams,
-      png_charpp params)
+insert_hIST(png_structp png_ptr, png_infop info_ptr, int nparams, png_charpp params)
 {
   int i;
   png_uint_16 freq[256];
@@ -1361,56 +1089,6 @@ insert_hIST(png_structp png_ptr, png_infop info_ptr, int nparams,
   png_set_hIST(png_ptr, info_ptr, freq);
 }

-static png_byte
-bval(png_const_structrp png_ptr, png_charp param, unsigned int maxval)
-{
-   char *endptr = NULL;
-   unsigned long int l = strtoul(param, &endptr, 0/*base*/);
-
-   if (param[0] && *endptr == 0 && l <= maxval)
-      return (png_byte)l;
-
-   else
-      png_error(png_ptr, "sBIT: invalid sBIT value");
-}
-
-static void
-insert_sBIT(png_structp png_ptr, png_infop info_ptr, int nparams,
-      png_charpp params)
-{
-   const int ct = png_get_color_type(png_ptr, info_ptr);
-   const int c = (ct & PNG_COLOR_MASK_COLOR ? 3 : 1) +
-      (ct & PNG_COLOR_MASK_ALPHA ? 1 : 0);
-   const unsigned int maxval =
-      ct & PNG_COLOR_MASK_PALETTE ? 8U : png_get_bit_depth(png_ptr, info_ptr);
-   png_color_8 sBIT;
-
-   if (nparams != c)
-      png_error(png_ptr, "sBIT: incorrect parameter count");
-
-   if (ct & PNG_COLOR_MASK_COLOR)
-   {
-      sBIT.red = bval(png_ptr, params[0], maxval);
-      sBIT.green = bval(png_ptr, params[1], maxval);
-      sBIT.blue = bval(png_ptr, params[2], maxval);
-      sBIT.gray = 42;
-   }
-
-   else
-   {
-      sBIT.red = sBIT.green = sBIT.blue = 42;
-      sBIT.gray = bval(png_ptr, params[0], maxval);
-   }
-
-   if (ct & PNG_COLOR_MASK_ALPHA)
-      sBIT.alpha = bval(png_ptr, params[nparams-1], maxval);
-
-   else
-      sBIT.alpha = 42;
-
-   png_set_sBIT(png_ptr, info_ptr, &sBIT);
-}
-
 #if 0
 static void
 insert_sPLT(png_structp png_ptr, png_infop info_ptr, int nparams, png_charpp params)
@@ -1538,11 +1216,6 @@ find_insert(png_const_charp what, png_charp param)
            return make_insert(what, insert_hIST, nparams, parameter_list);
         break;

-      case CHUNK(115,66,73,84): /* sBIT */
-         if (nparams <= 4)
-            return make_insert(what, insert_sBIT, nparams, parameter_list);
-         break;
-
 #if 0
      case CHUNK(115,80,76,84):  /* sPLT */
         return make_insert(what, insert_sPLT, nparams, parameter_list);
@@ -1558,80 +1231,6 @@ find_insert(png_const_charp what, png_charp param)
   return NULL;
 }

-/* This is necessary because libpng expects writeable strings for things like
- * text chunks (maybe this should be fixed...)
- */
-static png_charp
-strstash(png_const_charp foo)
-{
-   /* The program indicates a memory allocation error by crashing, this is by
-    * design.
-    */
-   if (foo != NULL)
-   {
-      png_charp bar = malloc(strlen(foo)+1);
-      return strcpy(bar, foo);
-   }
-
-   return NULL;
-}
-
-static png_charp
-strstash_list(const png_const_charp *text)
-{
-   size_t foo = 0;
-   png_charp result, bar;
-   const png_const_charp *line = text;
-
-   while (*line != NULL)
-      foo += strlen(*line++);
-
-   result = bar = malloc(foo+1);
-
-   line = text;
-   while (*line != NULL)
-   {
-      foo = strlen(*line);
-      memcpy(bar, *line++, foo);
-      bar += foo;
-   }
-
-   *bar = 0;
-   return result;
-}
-
-/* These are used to insert Copyright and Licence fields, they allow the text to
- * have \n unlike the --insert option.
- */
-static chunk_insert *
-add_tEXt(const char *key, const png_const_charp *text)
-{
-   static char what[5] = { 116, 69, 88, 116, 0 };
-   png_charp parameter_list[3];
-
-   parameter_list[0] = strstash(key);
-   parameter_list[1] = strstash_list(text);
-   parameter_list[2] = NULL;
-
-   return make_insert(what, insert_tEXt, 2, parameter_list);
-}
-
-static chunk_insert *
-add_iTXt(const char *key, const char *language, const char *language_key,
-      const png_const_charp *text)
-{
-   static char what[5] = { 105, 84, 88, 116, 0 };
-   png_charp parameter_list[5];
-
-   parameter_list[0] = strstash(key);
-   parameter_list[1] = strstash(language);
-   parameter_list[2] = strstash(language_key);
-   parameter_list[3] = strstash_list(text);
-   parameter_list[4] = NULL;
-
-   return make_insert(what, insert_iTXt, 4, parameter_list);
-}
-
 /* This is a not-very-good parser for a sequence of numbers (including 0).  It
 * doesn't accept some apparently valid things, but it accepts all the sensible
 * combinations.
@@ -1681,8 +1280,6 @@ main(int argc, char **argv)
   const char *file_name = NULL;
   int color_type = 8; /* invalid */
   int bit_depth = 32; /* invalid */
-   int small = 0; /* make full size images */
-   int tRNS = 0; /* don't output a tRNS chunk */
   unsigned int colors[5];
   unsigned int filters = PNG_ALL_FILTERS;
   png_fixed_point gamma = 0; /* not set */
@@ -1695,18 +1292,6 @@ main(int argc, char **argv)
   {
      char *arg = *++argv;

-      if (strcmp(arg, "--small") == 0)
-      {
-         small = 1;
-         continue;
-      }
-
-      if (strcmp(arg, "--tRNS") == 0)
-      {
-         tRNS = 1;
-         continue;
-      }
-
      if (strcmp(arg, "--sRGB") == 0)
      {
         gamma = PNG_DEFAULT_sRGB;
@@ -1847,10 +1432,9 @@ main(int argc, char **argv)

   if (color_type == 8 || bit_depth == 32)
   {
-      fprintf(stderr, "usage: makepng [--small] [--sRGB|--linear|--1.8] "
+      fprintf(stderr, "usage: makepng [--sRGB|--linear|--1.8] "
         "[--color=...] color-type bit-depth [file-name]\n"
-         "  Make a test PNG file, by default writes to stdout.\n"
-         "  Other options are available, UTSL.\n");
+         "  Make a test PNG file, by default writes to stdout.\n");
      exit(1);
   }

@@ -1869,19 +1453,10 @@ main(int argc, char **argv)
         }
   }

-   /* small and colors are incomparible (will probably crash if both are used at
-    * the same time!)
-    */
-   if (small && colors[0] != 0)
-   {
-      fprintf(stderr, "makepng: --color --small: only one at a time!\n");
-      exit(1);
-   }
-
   /* Restrict the filters for more speed to those we know are used for the
    * generated images.
    */
-   if (filters == PNG_ALL_FILTERS && !small/*small provides defaults*/)
+   if (filters == PNG_ALL_FILTERS)
   {
      if ((color_type & PNG_COLOR_MASK_PALETTE) != 0 || bit_depth < 8)
         filters = PNG_FILTER_NONE;
@@ -1899,39 +1474,9 @@ main(int argc, char **argv)
         filters &= ~PNG_FILTER_NONE;
   }

-   /* Insert standard copyright and licence text. */
-   {
-      static png_const_charp copyright[] =
-      {
-         COPYRIGHT, /* ISO-Latin-1 */
-         NULL
-      };
-      static png_const_charp licensing[] =
-      {
-         IMAGE_LICENSING, /* UTF-8 */
-         NULL
-      };
-
-      chunk_insert *new_insert;
-
-      new_insert = add_tEXt("Copyright", copyright);
-      if (new_insert != NULL)
-      {
-         *insert_ptr = new_insert;
-         insert_ptr = &new_insert->next;
-      }
-
-      new_insert = add_iTXt("Licensing", "en", NULL, licensing);
-      if (new_insert != NULL)
-      {
-         *insert_ptr = new_insert;
-         insert_ptr = &new_insert->next;
-      }
-   }
-
   {
      int ret = write_png(&file_name, fp, color_type, bit_depth, gamma,
-         head_insert, filters, colors, small, tRNS);
+         head_insert, filters, colors);

      if (ret != 0 && file_name != NULL)
         remove(file_name);
--- a/contrib/libtests/pngimage.c
+++ b/contrib/libtests/pngimage.c
@@ -1,8 +1,8 @@
 /* pngimage.c
 *
- * Copyright (c) 2015,2016 John Cunningham Bowler
+ * Copyright (c) 2014 John Cunningham Bowler
 *
- * Last changed in libpng 1.6.24 [August 4, 2016]
+ * Last changed in libpng 1.6.10 [March 6, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -36,28 +36,7 @@
 #  include <setjmp.h> /* because png.h did *not* include this */
 #endif

-/* 1.6.1 added support for the configure test harness, which uses 77 to indicate
- * a skipped test, in earlier versions we need to succeed on a skipped test, so:
- */
-#if PNG_LIBPNG_VER >= 10601 && defined(HAVE_CONFIG_H)
-#  define SKIP 77
-#else
-#  define SKIP 0
-#endif
-
-#if PNG_LIBPNG_VER < 10700
-   /* READ_PNG and WRITE_PNG were not defined, so: */
-#  ifdef PNG_INFO_IMAGE_SUPPORTED
-#     ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-#        define PNG_READ_PNG_SUPPORTED
-#     endif /* SEQUENTIAL_READ */
-#     ifdef PNG_WRITE_SUPPORTED
-#        define PNG_WRITE_PNG_SUPPORTED
-#     endif /* WRITE */
-#  endif /* INFO_IMAGE */
-#endif /* pre 1.7.0 */
-
-#ifdef PNG_READ_PNG_SUPPORTED
+#if defined(PNG_INFO_IMAGE_SUPPORTED) && defined(PNG_SEQUENTIAL_READ_SUPPORTED)
 /* If a transform is valid on both read and write this implies that if the
 * transform is applied to read it must also be applied on write to produce
 * meaningful data.  This is because these transforms when performed on read
@@ -257,12 +236,10 @@ static struct transform_info
       */
 #endif
 #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-   T(SCALE_16,            NONE, X,   X,   16,  R),
+   T(SCALE_16,            NONE, X,   X,   16,  R)
      /* scales 16-bit components to 8-bits. */
 #endif

-   { NULL /*name*/, 0, 0, 0, 0, 0, 0, 0/*!tested*/ }
-
 #undef T
 };

@@ -317,7 +294,7 @@ transform_name(int t)

   t &= -t; /* first set bit */

-   for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
+   for (i=0; i<TTABLE_SIZE; ++i)
   {
      if ((transform_info[i].transform & t) != 0)
         return transform_info[i].name;
@@ -338,7 +315,7 @@ validate_T(void)
 {
   unsigned int i;

-   for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
+   for (i=0; i<TTABLE_SIZE; ++i)
   {
      if (transform_info[i].when & TRANSFORM_R)
         read_transforms |= transform_info[i].transform;
@@ -406,7 +383,7 @@ buffer_destroy(struct buffer *buffer)
   buffer_destroy_list(list);
 }

-#ifdef PNG_WRITE_PNG_SUPPORTED
+#ifdef PNG_WRITE_SUPPORTED
 static void
 buffer_start_write(struct buffer *buffer)
 {
@@ -528,7 +505,6 @@ typedef enum
 #define SKIP_BUGS       0x100 /* Skip over known bugs */
 #define LOG_SKIPPED     0x200 /* Log skipped bugs */
 #define FIND_BAD_COMBOS 0x400 /* Attempt to deduce bad combos */
-#define LIST_COMBOS     0x800 /* List combos by name */

 /* Result masks apply to the result bits in the 'results' field below; these
 * bits are simple 1U<<error_level.  A pass requires either nothing worse than
@@ -576,7 +552,7 @@ struct display
   png_structp    read_pp;
   png_infop      read_ip;

-#  ifdef PNG_WRITE_PNG_SUPPORTED
+#  ifdef PNG_WRITE_SUPPORTED
      /* Used to write a new image (the original info_ptr is used) */
      png_structp   write_pp;
      struct buffer written_file;   /* where the file gets written */
@@ -603,7 +579,7 @@ display_init(struct display *dp)
   dp->read_ip = NULL;
   buffer_init(&dp->original_file);

-#  ifdef PNG_WRITE_PNG_SUPPORTED
+#  ifdef PNG_WRITE_SUPPORTED
      dp->write_pp = NULL;
      buffer_init(&dp->written_file);
 #  endif
@@ -616,7 +592,7 @@ display_clean_read(struct display *dp)
      png_destroy_read_struct(&dp->read_pp, &dp->read_ip, NULL);
 }

-#ifdef PNG_WRITE_PNG_SUPPORTED
+#ifdef PNG_WRITE_SUPPORTED
 static void
 display_clean_write(struct display *dp)
 {
@@ -628,7 +604,7 @@ display_clean_write(struct display *dp)
 static void
 display_clean(struct display *dp)
 {
-#  ifdef PNG_WRITE_PNG_SUPPORTED
+#  ifdef PNG_WRITE_SUPPORTED
      display_clean_write(dp);
 #  endif
   display_clean_read(dp);
@@ -646,7 +622,7 @@ static void
 display_destroy(struct display *dp)
 {
    /* Release any memory held in the display. */
-#  ifdef PNG_WRITE_PNG_SUPPORTED
+#  ifdef PNG_WRITE_SUPPORTED
      buffer_destroy(&dp->written_file);
 #  endif

@@ -714,35 +690,7 @@ display_log(struct display *dp, error_level level, const char *fmt, ...)
         int tr = dp->transforms;

         if (is_combo(tr))
-         {
-            if (dp->options & LIST_COMBOS)
-            {
-               int trx = tr;
-
-               fprintf(stderr, "(");
-               if (trx)
-               {
-                  int start = 0;
-
-                  while (trx)
-                  {
-                     int trz = trx & -trx;
-
-                     if (start) fprintf(stderr, "+");
-                     fprintf(stderr, "%s", transform_name(trz));
-                     start = 1;
-                     trx &= ~trz;
-                  }
-               }
-
-               else
-                  fprintf(stderr, "-");
-               fprintf(stderr, ")");
-            }
-
-            else
-               fprintf(stderr, "(0x%x)", tr);
-         }
+            fprintf(stderr, "(0x%x)", tr);

         else
            fprintf(stderr, "(%s)", transform_name(tr));
@@ -962,13 +910,13 @@ update_display(struct display *dp)
      int bd = dp->bit_depth;
      unsigned int i;

-      for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
+      for (i=0; i<TTABLE_SIZE; ++i)
      {
         int transform = transform_info[i].transform;

         if ((transform_info[i].valid_chunks == 0 ||
               (transform_info[i].valid_chunks & chunks) != 0) &&
-            (transform_info[i].color_mask_required & ct) ==
+            (transform_info[i].color_mask_required & ct) == 
               transform_info[i].color_mask_required &&
            (transform_info[i].color_mask_absent & ct) == 0 &&
            (transform_info[i].bit_depths & bd) != 0 &&
@@ -987,6 +935,9 @@ update_display(struct display *dp)

      dp->active_transforms = active;
      dp->ignored_transforms = inactive; /* excluding write-only transforms */
+
+      if (active == 0)
+         display_log(dp, INTERNAL_ERROR, "bad transform table");
   }
 }

@@ -1026,7 +977,7 @@ compare_read(struct display *dp, int applied_transforms)
   {
      unsigned long chunks =
         png_get_valid(dp->read_pp, dp->read_ip, 0xffffffff);
-
+      
      if (chunks != dp->chunks)
         display_log(dp, APP_FAIL, "PNG chunks changed from 0x%lx to 0x%lx",
            (unsigned long)dp->chunks, chunks);
@@ -1093,7 +1044,6 @@ compare_read(struct display *dp, int applied_transforms)
      }

      else
-#     ifdef PNG_sBIT_SUPPORTED
      {
         unsigned long y;
         int bpp;   /* bits-per-pixel then bytes-per-pixel */
@@ -1170,8 +1120,8 @@ compare_read(struct display *dp, int applied_transforms)
         {
            int b;

-            case 16: /* Two bytes per component, big-endian */
-               for (b = (bpp >> 4); b > 0; --b)
+            case 16: /* Two bytes per component, bit-endian */
+               for (b = (bpp >> 4); b > 0; )
               {
                  unsigned int sig = (unsigned int)(0xffff0000 >> sig_bits[b]);

@@ -1255,16 +1205,12 @@ compare_read(struct display *dp, int applied_transforms)
            }
         } /* for y */
      }
-#     else /* !sBIT */
-         display_log(dp, INTERNAL_ERROR,
-               "active shift transform but no sBIT support");
-#     endif /* !sBIT */
   }

   return 1; /* compare succeeded */
 }

-#ifdef PNG_WRITE_PNG_SUPPORTED
+#ifdef PNG_WRITE_SUPPORTED
 static void
 buffer_write(struct display *dp, struct buffer *buffer, png_bytep data,
   png_size_t size)
@@ -1363,7 +1309,7 @@ write_png(struct display *dp, png_infop ip, int transforms)
    */
   display_clean_write(dp);
 }
-#endif /* WRITE_PNG */
+#endif /* WRITE_SUPPORTED */

 static int
 skip_transform(struct display *dp, int tr)
@@ -1425,7 +1371,7 @@ test_one_file(struct display *dp, const char *filename)
         return; /* no point testing more */
   }

-#ifdef PNG_WRITE_PNG_SUPPORTED
+#ifdef PNG_WRITE_SUPPORTED
   /* Second test: write the original PNG data out to a new file (to test the
    * write side) then read the result back in and make sure that it hasn't
    * changed.
@@ -1466,7 +1412,7 @@ test_one_file(struct display *dp, const char *filename)
          * out and read it back in again (without the reversible transforms)
          * we should get back to the place where we started.
          */
-#ifdef PNG_WRITE_PNG_SUPPORTED
+#ifdef PNG_WRITE_SUPPORTED
         if ((current & write_transforms) == current)
         {
            /* All transforms reversible: write the PNG with the transformations
@@ -1642,12 +1588,6 @@ main(const int argc, const char * const * const argv)
      else if (strcmp(name, "--nofind-bad-combos") == 0)
         d.options &= ~FIND_BAD_COMBOS;

-      else if (strcmp(name, "--list-combos") == 0)
-         d.options |= LIST_COMBOS;
-
-      else if (strcmp(name, "--nolist-combos") == 0)
-         d.options &= ~LIST_COMBOS;
-
      else if (name[0] == '-' && name[1] == '-')
      {
         fprintf(stderr, "pngimage: %s: unknown option\n", name);
@@ -1702,11 +1642,11 @@ main(const int argc, const char * const * const argv)
      return errors != 0;
   }
 }
-#else /* !READ_PNG */
+#else /* !PNG_INFO_IMAGE_SUPPORTED || !PNG_READ_SUPPORTED */
 int
 main(void)
 {
   fprintf(stderr, "pngimage: no support for png_read/write_image\n");
-   return SKIP;
+   return 77;
 }
 #endif
--- a/contrib/libtests/pngstest-errors.h
+++ b/contrib/libtests/pngstest-errors.h
@@ -1,165 +0,0 @@
-/* contrib/libtests/pngstest-errors.h
- *
- * BUILT USING: libpng version 1.6.19beta03 - September 25, 2015
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * THIS IS A MACHINE GENERATED FILE: do not edit it directly!
- * Instead run:
- *
- *    pngstest --accumulate
- *
- * on as many PNG files as possible; at least PNGSuite and
- * contrib/libtests/testpngs.
- */
-static png_uint_16 gpc_error[16/*in*/][16/*out*/][4/*a*/] =
-{
- { /* input: sRGB-gray */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 372, 0 }, { 0, 0, 372, 0 }, { 0, 0, 372, 0 }, { 0, 0, 372, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: sRGB-gray+alpha */
-  { 0, 19, 0, 0 }, { 0, 0, 0, 0 }, { 0, 20, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 897, 788, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: sRGB-rgb */
-  { 0, 0, 19, 0 }, { 0, 0, 19, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 893, 0 }, { 0, 0, 893, 0 }, { 0, 0, 811, 0 }, { 0, 0, 811, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: sRGB-rgb+alpha */
-  { 0, 16, 17, 0 }, { 0, 17, 17, 0 }, { 0, 19, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 850, 875, 0 }, { 0, 850, 875, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: linear-gray */
-  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: linear-gray+alpha */
-  { 0, 74, 9, 0 }, { 0, 20, 9, 0 }, { 0, 74, 9, 0 }, { 0, 20, 9, 0 },
-  { 0, 0, 0, 0 }, { 0, 1, 0, 0 }, { 0, 0, 0, 0 }, { 0, 1, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: linear-rgb */
-  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
-  { 0, 0, 4, 0 }, { 0, 0, 4, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: linear-rgb+alpha */
-  { 0, 126, 143, 0 }, { 0, 11, 7, 0 }, { 0, 74, 9, 0 }, { 0, 17, 9, 0 },
-  { 0, 4, 4, 0 }, { 0, 5, 4, 0 }, { 0, 0, 0, 0 }, { 0, 1, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-sRGB-gray */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-sRGB-gray+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-sRGB-rgb */
-  { 0, 0, 13, 0 }, { 0, 0, 13, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
-  { 0, 0, 673, 0 }, { 0, 0, 673, 0 }, { 0, 0, 674, 0 }, { 0, 0, 674, 0 },
-  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 460, 0 }, { 0, 0, 460, 0 }, { 0, 0, 263, 0 }, { 0, 0, 263, 0 }
- }, { /* input: color-mapped-sRGB-rgb+alpha */
-  { 0, 6, 8, 0 }, { 0, 7, 8, 0 }, { 0, 75, 9, 0 }, { 0, 9, 9, 0 },
-  { 0, 585, 427, 0 }, { 0, 585, 427, 0 }, { 0, 717, 514, 0 }, { 0, 717, 514, 0 },
-  { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 13323, 460, 0 }, { 0, 427, 460, 0 }, { 0, 16480, 263, 0 }, { 0, 243, 263, 0 }
- }, { /* input: color-mapped-linear-gray */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 282, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-gray+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 253, 282, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-rgb */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 265, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-rgb+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 243, 265, 0 }
- }
-};
-static png_uint_16 gpc_error_via_linear[16][4/*out*/][4] =
-{
- { /* input: sRGB-gray */
-  { 0, 0, 7, 0 }, { 0, 0, 7, 0 }, { 0, 0, 7, 0 }, { 0, 0, 7, 0 }
- }, { /* input: sRGB-gray+alpha */
-  { 0, 15, 15, 0 }, { 0, 186, 15, 0 }, { 0, 15, 15, 0 }, { 0, 186, 15, 0 }
- }, { /* input: sRGB-rgb */
-  { 0, 0, 20, 0 }, { 0, 0, 20, 0 }, { 0, 0, 15, 0 }, { 0, 0, 15, 0 }
- }, { /* input: sRGB-rgb+alpha */
-  { 0, 16, 17, 0 }, { 0, 187, 17, 0 }, { 0, 15, 15, 0 }, { 0, 186, 15, 0 }
- }, { /* input: linear-gray */
-  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }
- }, { /* input: linear-gray+alpha */
-  { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }
- }, { /* input: linear-rgb */
-  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }
- }, { /* input: linear-rgb+alpha */
-  { 0, 1, 1, 0 }, { 0, 9, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }
- }, { /* input: color-mapped-sRGB-gray */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-sRGB-gray+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-sRGB-rgb */
-  { 0, 0, 13, 0 }, { 0, 0, 13, 0 }, { 0, 0, 14, 0 }, { 0, 0, 14, 0 }
- }, { /* input: color-mapped-sRGB-rgb+alpha */
-  { 0, 4, 8, 0 }, { 0, 9, 8, 0 }, { 0, 9, 5, 0 }, { 0, 32, 5, 0 }
- }, { /* input: color-mapped-linear-gray */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-gray+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-rgb */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }, { /* input: color-mapped-linear-rgb+alpha */
-  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
- }
-};
-static png_uint_16 gpc_error_to_colormap[8/*i*/][8/*o*/][4] =
-{
- { /* input: sRGB-gray */
-  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
-  { 0, 0, 560, 0 }, { 0, 0, 560, 0 }, { 0, 0, 560, 0 }, { 0, 0, 560, 0 }
- }, { /* input: sRGB-gray+alpha */
-  { 0, 19, 9, 0 }, { 0, 255, 9, 25 }, { 0, 88, 9, 0 }, { 0, 255, 9, 25 },
-  { 0, 1012, 928, 0 }, { 0, 16026, 928, 6425 }, { 0, 1012, 928, 0 }, { 0, 16026, 928, 6425 }
- }, { /* input: sRGB-rgb */
-  { 0, 0, 19, 0 }, { 0, 0, 19, 0 }, { 0, 0, 25, 0 }, { 0, 0, 25, 0 },
-  { 0, 0, 962, 0 }, { 0, 0, 962, 0 }, { 0, 0, 13677, 0 }, { 0, 0, 13677, 0 }
- }, { /* input: sRGB-rgb+alpha */
-  { 0, 63, 77, 0 }, { 0, 255, 19, 25 }, { 0, 225, 25, 0 }, { 0, 255, 25, 67 },
-  { 0, 17534, 18491, 0 }, { 0, 15736, 2824, 6425 }, { 0, 14019, 13677, 0 }, { 0, 50115, 13677, 17219 }
- }, { /* input: linear-gray */
-  { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 73, 0 },
-  { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }
- }, { /* input: linear-gray+alpha */
-  { 0, 74, 74, 0 }, { 0, 255, 74, 25 }, { 0, 99, 74, 0 }, { 0, 255, 74, 25 },
-  { 0, 18919, 18907, 0 }, { 0, 24549, 18907, 6553 }, { 0, 18919, 18907, 0 }, { 0, 24549, 18907, 6553 }
- }, { /* input: linear-rgb */
-  { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 98, 0 }, { 0, 0, 98, 0 },
-  { 0, 0, 18664, 0 }, { 0, 0, 18664, 0 }, { 0, 0, 24998, 0 }, { 0, 0, 24998, 0 }
- }, { /* input: linear-rgb+alpha */
-  { 0, 181, 196, 0 }, { 0, 255, 61, 25 }, { 206, 187, 98, 0 }, { 0, 255, 98, 67 },
-  { 0, 18141, 18137, 0 }, { 0, 17494, 17504, 6553 }, { 0, 24979, 24992, 0 }, { 0, 49172, 24992, 17347 }
- }
-};
-/* END MACHINE GENERATED */
--- a/contrib/libtests/pngstest.c
+++ b/contrib/libtests/pngstest.c
@@ -1,8 +1,9 @@
 /*-
 * pngstest.c
 *
- * Last changed in libpng 1.6.31 [July 27, 2017]
- * Copyright (c) 2013-2017 John Cunningham Bowler
+ * Copyright (c) 2013-2014 John Cunningham Bowler
+ *
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -34,15 +35,6 @@
 #  include "../../png.h"
 #endif

-/* 1.6.1 added support for the configure test harness, which uses 77 to indicate
- * a skipped test, in earlier versions we need to succeed on a skipped test, so:
- */
-#if PNG_LIBPNG_VER >= 10601 && defined(HAVE_CONFIG_H)
-#  define SKIP 77
-#else
-#  define SKIP 0
-#endif
-
 #ifdef PNG_SIMPLIFIED_READ_SUPPORTED /* Else nothing can be done */
 #include "../tools/sRGB.h"

@@ -107,18 +99,10 @@ make_random_bytes(png_uint_32* seed, void* pv, size_t size)
   seed[1] = u1;
 }

-static png_uint_32 color_seed[2];
-
-static void
-reseed(void)
-{
-   color_seed[0] = 0x12345678U;
-   color_seed[1] = 0x9abcdefU;
-}
-
 static void
 random_color(png_colorp color)
 {
+   static png_uint_32 color_seed[2] = { 0x12345678, 0x9abcdef };
   make_random_bytes(color_seed, color, sizeof *color);
 }

@@ -323,7 +307,7 @@ compare_16bit(int v1, int v2, int error_limit, int multiple_algorithms)
 }
 #endif /* unused */

-#define USE_FILE 1       /* else memory */
+#define READ_FILE 1      /* else memory */
 #define USE_STDIO 2      /* else use file name */
 #define STRICT 4         /* fail on warnings too */
 #define VERBOSE 8
@@ -332,19 +316,16 @@ compare_16bit(int v1, int v2, int error_limit, int multiple_algorithms)
 #define ACCUMULATE 64
 #define FAST_WRITE 128
 #define sRGB_16BIT 256
-#define NO_RESEED  512   /* do not reseed on each new file */
-#define GBG_ERROR 1024   /* do not ignore the gamma+background_rgb_to_gray
-                          * libpng warning. */

 static void
 print_opts(png_uint_32 opts)
 {
-   if (opts & USE_FILE)
+   if (opts & READ_FILE)
      printf(" --file");
   if (opts & USE_STDIO)
      printf(" --stdio");
-   if (!(opts & STRICT))
-      printf(" --nostrict");
+   if (opts & STRICT)
+      printf(" --strict");
   if (opts & VERBOSE)
      printf(" --verbose");
   if (opts & KEEP_TMPFILES)
@@ -357,12 +338,6 @@ print_opts(png_uint_32 opts)
      printf(" --slow");
   if (opts & sRGB_16BIT)
      printf(" --sRGB-16bit");
-   if (opts & NO_RESEED)
-      printf(" --noreseed");
-#if PNG_LIBPNG_VER < 10700 /* else on by default */
-   if (opts & GBG_ERROR)
-      printf(" --fault-gbg-warning");
-#endif
 }

 #define FORMAT_NO_CHANGE 0x80000000 /* additional flag */
@@ -640,7 +615,7 @@ freeimage(Image *image)

   if (image->tmpfile_name[0] != 0 && (image->opts & KEEP_TMPFILES) == 0)
   {
-      (void)remove(image->tmpfile_name);
+      remove(image->tmpfile_name);
      image->tmpfile_name[0] = 0;
   }
 }
@@ -766,15 +741,8 @@ checkopaque(Image *image)
      return logerror(image, image->file_name, ": opaque not NULL", "");
   }

-   /* Separate out the gamma+background_rgb_to_gray warning because it may
-    * produce opaque component errors:
-    */
-   else if (image->image.warning_or_error != 0 &&
-            (strcmp(image->image.message,
-               "libpng does not support gamma+background+rgb_to_gray") == 0 ?
-                  (image->opts & GBG_ERROR) != 0 : (image->opts & STRICT) != 0))
-      return logerror(image, image->file_name, (image->opts & GBG_ERROR) != 0 ?
-                      " --fault-gbg-warning" : " --strict", "");
+   else if (image->image.warning_or_error != 0 && (image->opts & STRICT) != 0)
+      return logerror(image, image->file_name, " --strict", "");

   else
      return 1;
@@ -2016,7 +1984,156 @@ static void (* const gpc_fn_colormapped[8/*in*/][8/*out*/])
 * gpc_error_to_colormap.
 */
 #if PNG_FORMAT_FLAG_COLORMAP == 8 /* extra check also required */
-#  include "pngstest-errors.h" /* machine generated */
+/* START MACHINE GENERATED */
+static png_uint_16 gpc_error[16/*in*/][16/*out*/][4/*a*/] =
+{
+ { /* input: sRGB-gray */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 372, 0 }, { 0, 0, 372, 0 }, { 0, 0, 372, 0 }, { 0, 0, 372, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: sRGB-gray+alpha */
+  { 0, 18, 0, 0 }, { 0, 0, 0, 0 }, { 0, 20, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 897, 788, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: sRGB-rgb */
+  { 0, 0, 19, 0 }, { 0, 0, 19, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 893, 0 }, { 0, 0, 893, 0 }, { 0, 0, 811, 0 }, { 0, 0, 811, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: sRGB-rgb+alpha */
+  { 0, 4, 13, 0 }, { 0, 14, 13, 0 }, { 0, 19, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 832, 764, 0 }, { 0, 832, 764, 0 }, { 0, 897, 788, 0 }, { 0, 897, 788, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: linear-gray */
+  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: linear-gray+alpha */
+  { 0, 74, 9, 0 }, { 0, 20, 9, 0 }, { 0, 74, 9, 0 }, { 0, 20, 9, 0 },
+  { 0, 0, 0, 0 }, { 0, 1, 0, 0 }, { 0, 0, 0, 0 }, { 0, 1, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: linear-rgb */
+  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
+  { 0, 0, 4, 0 }, { 0, 0, 4, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: linear-rgb+alpha */
+  { 0, 126, 143, 0 }, { 0, 9, 7, 0 }, { 0, 74, 9, 0 }, { 0, 16, 9, 0 },
+  { 0, 4, 4, 0 }, { 0, 5, 4, 0 }, { 0, 0, 0, 0 }, { 0, 1, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-sRGB-gray */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-sRGB-gray+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-sRGB-rgb */
+  { 0, 0, 13, 0 }, { 0, 0, 13, 0 }, { 0, 0, 8, 0 }, { 0, 0, 8, 0 },
+  { 0, 0, 673, 0 }, { 0, 0, 673, 0 }, { 0, 0, 674, 0 }, { 0, 0, 674, 0 },
+  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 460, 0 }, { 0, 0, 460, 0 }, { 0, 0, 263, 0 }, { 0, 0, 263, 0 }
+ }, { /* input: color-mapped-sRGB-rgb+alpha */
+  { 0, 6, 8, 0 }, { 0, 7, 8, 0 }, { 0, 75, 8, 0 }, { 0, 9, 8, 0 },
+  { 0, 585, 427, 0 }, { 0, 585, 427, 0 }, { 0, 717, 409, 0 }, { 0, 717, 409, 0 },
+  { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 13323, 460, 0 }, { 0, 334, 460, 0 }, { 0, 16480, 263, 0 }, { 0, 243, 263, 0 }
+ }, { /* input: color-mapped-linear-gray */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 282, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-gray+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 253, 282, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-rgb */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 265, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-rgb+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 },
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 243, 265, 0 }
+ }
+};
+static png_uint_16 gpc_error_via_linear[16][4/*out*/][4] =
+{
+ { /* input: sRGB-gray */
+  { 0, 0, 7, 0 }, { 0, 0, 7, 0 }, { 0, 0, 7, 0 }, { 0, 0, 7, 0 }
+ }, { /* input: sRGB-gray+alpha */
+  { 0, 15, 15, 0 }, { 0, 186, 15, 0 }, { 0, 15, 15, 0 }, { 0, 186, 15, 0 }
+ }, { /* input: sRGB-rgb */
+  { 0, 0, 19, 0 }, { 0, 0, 19, 0 }, { 0, 0, 15, 0 }, { 0, 0, 15, 0 }
+ }, { /* input: sRGB-rgb+alpha */
+  { 0, 12, 14, 0 }, { 0, 180, 14, 0 }, { 0, 14, 15, 0 }, { 0, 186, 15, 0 }
+ }, { /* input: linear-gray */
+  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }
+ }, { /* input: linear-gray+alpha */
+  { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }
+ }, { /* input: linear-rgb */
+  { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }, { 0, 0, 1, 0 }
+ }, { /* input: linear-rgb+alpha */
+  { 0, 1, 1, 0 }, { 0, 8, 1, 0 }, { 0, 1, 1, 0 }, { 0, 1, 1, 0 }
+ }, { /* input: color-mapped-sRGB-gray */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-sRGB-gray+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-sRGB-rgb */
+  { 0, 0, 13, 0 }, { 0, 0, 13, 0 }, { 0, 0, 14, 0 }, { 0, 0, 14, 0 }
+ }, { /* input: color-mapped-sRGB-rgb+alpha */
+  { 0, 4, 8, 0 }, { 0, 9, 8, 0 }, { 0, 8, 3, 0 }, { 0, 32, 3, 0 }
+ }, { /* input: color-mapped-linear-gray */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-gray+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-rgb */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }, { /* input: color-mapped-linear-rgb+alpha */
+  { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }, { 0, 0, 0, 0 }
+ }
+};
+static png_uint_16 gpc_error_to_colormap[8/*i*/][8/*o*/][4] =
+{
+ { /* input: sRGB-gray */
+  { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 }, { 0, 0, 9, 0 },
+  { 0, 0, 560, 0 }, { 0, 0, 560, 0 }, { 0, 0, 560, 0 }, { 0, 0, 560, 0 }
+ }, { /* input: sRGB-gray+alpha */
+  { 0, 19, 2, 0 }, { 0, 255, 2, 25 }, { 0, 88, 2, 0 }, { 0, 255, 2, 25 },
+  { 0, 1012, 745, 0 }, { 0, 16026, 745, 6425 }, { 0, 1012, 745, 0 }, { 0, 16026, 745, 6425 }
+ }, { /* input: sRGB-rgb */
+  { 0, 0, 19, 0 }, { 0, 0, 19, 0 }, { 0, 0, 25, 0 }, { 0, 0, 25, 0 },
+  { 0, 0, 937, 0 }, { 0, 0, 937, 0 }, { 0, 0, 13677, 0 }, { 0, 0, 13677, 0 }
+ }, { /* input: sRGB-rgb+alpha */
+  { 0, 63, 77, 0 }, { 0, 255, 19, 25 }, { 0, 220, 25, 0 }, { 0, 255, 25, 67 },
+  { 0, 17534, 18491, 0 }, { 0, 15614, 2824, 6425 }, { 0, 14019, 13677, 0 }, { 0, 48573, 13677, 17219 }
+ }, { /* input: linear-gray */
+  { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 73, 0 },
+  { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }, { 0, 0, 18817, 0 }
+ }, { /* input: linear-gray+alpha */
+  { 0, 74, 74, 0 }, { 0, 255, 74, 25 }, { 0, 97, 74, 0 }, { 0, 255, 74, 25 },
+  { 0, 18919, 18907, 0 }, { 0, 24549, 18907, 6552 }, { 0, 18919, 18907, 0 }, { 0, 24549, 18907, 6552 }
+ }, { /* input: linear-rgb */
+  { 0, 0, 73, 0 }, { 0, 0, 73, 0 }, { 0, 0, 98, 0 }, { 0, 0, 98, 0 },
+  { 0, 0, 18664, 0 }, { 0, 0, 18664, 0 }, { 0, 0, 24998, 0 }, { 0, 0, 24998, 0 }
+ }, { /* input: linear-rgb+alpha */
+  { 0, 181, 196, 0 }, { 0, 255, 61, 25 }, { 206, 187, 98, 0 }, { 0, 255, 98, 67 },
+  { 0, 18141, 18137, 0 }, { 0, 17494, 17504, 6553 }, { 0, 24979, 24992, 0 }, { 0, 46509, 24992, 17347 }
+ }
+};
+/* END MACHINE GENERATED */
 #endif /* COLORMAP flag check */
 #endif /* flag checks */

@@ -2037,7 +2154,7 @@ typedef struct
   int          in_opaque;   /* Value of input alpha that is opaque */
   int          is_palette;  /* Sample values come from the palette */
   int          accumulate;  /* Accumlate component errors (don't log) */
-   int          output_8bit; /* Output is 8-bit (else 16-bit) */
+   int          output_8bit; /* Output is 8 bit (else 16 bit) */

   void (*in_gp)(Pixel*, png_const_voidp);
   void (*out_gp)(Pixel*, png_const_voidp);
@@ -2610,9 +2727,9 @@ compare_two_images(Image *a, Image *b, int via_linear,
   const unsigned int b_sample = PNG_IMAGE_SAMPLE_SIZE(formatb);
   int alpha_added, alpha_removed;
   int bchannels;
+   int btoa[4];
   png_uint_32 y;
   Transform tr;
-   int btoa[4]={0,0,0,0};

   /* This should never happen: */
   if (width != b->image.width || height != b->image.height)
@@ -2711,7 +2828,7 @@ compare_two_images(Image *a, Image *b, int via_linear,

            else if (y >= b->image.colormap_entries)
            {
-               if ((b->opts & ACCUMULATE) == 0)
+               if ((a->opts & ACCUMULATE) == 0)
                  {
                  char pindex[9];
                  sprintf(pindex, "%lu[%lu]", (unsigned long)y,
@@ -2745,27 +2862,22 @@ compare_two_images(Image *a, Image *b, int via_linear,
       */
      else if ((a->opts & ACCUMULATE) == 0)
      {
-#        ifdef __GNUC__
-#           define BYTE_CHARS 20 /* 2^32: GCC sprintf warning */
-#        else
-#           define BYTE_CHARS 3 /* 2^8: real maximum value */
-#        endif
         /* Check the original image first,
          * TODO: deal with input images with bad pixel values?
          */
         if (amax >= a->image.colormap_entries)
         {
-            char pindex[3+2*BYTE_CHARS];
-            sprintf(pindex, "%d[%u]", amax,
-               (png_byte)/*SAFE*/a->image.colormap_entries);
+            char pindex[9];
+            sprintf(pindex, "%d[%lu]", amax,
+               (unsigned long)a->image.colormap_entries);
            return logerror(a, a->file_name, ": bad pixel index: ", pindex);
         }

         else if (bmax >= b->image.colormap_entries)
         {
-            char pindex[3+2*BYTE_CHARS];
-            sprintf(pindex, "%d[%u]", bmax,
-               (png_byte)/*SAFE*/b->image.colormap_entries);
+            char pindex[9];
+            sprintf(pindex, "%d[%lu]", bmax,
+               (unsigned long)b->image.colormap_entries);
            return logerror(b, b->file_name, ": bad pixel index: ", pindex);
         }
      }
@@ -2885,13 +2997,10 @@ compare_two_images(Image *a, Image *b, int via_linear,
               {
                  case 4:
                     if (pua[btoa[3]] != pub[3]) break;
-                     /* FALLTHROUGH */
                  case 3:
                     if (pua[btoa[2]] != pub[2]) break;
-                     /* FALLTHROUGH */
                  case 2:
                     if (pua[btoa[1]] != pub[1]) break;
-                     /* FALLTHROUGH */
                  case 1:
                     if (pua[btoa[0]] != pub[0]) break;
                     if (alpha_added != 4 && pub[alpha_added] != 65535) break;
@@ -2907,13 +3016,10 @@ compare_two_images(Image *a, Image *b, int via_linear,
               {
                  case 4:
                     if (psa[btoa[3]] != psb[3]) break;
-                     /* FALLTHROUGH */
                  case 3:
                     if (psa[btoa[2]] != psb[2]) break;
-                     /* FALLTHROUGH */
                  case 2:
                     if (psa[btoa[1]] != psb[1]) break;
-                     /* FALLTHROUGH */
                  case 1:
                     if (psa[btoa[0]] != psb[0]) break;
                     if (alpha_added != 4 && psb[alpha_added] != 255) break;
@@ -3051,14 +3157,14 @@ read_file(Image *image, png_uint_32 format, png_const_colorp background)
 static int
 read_one_file(Image *image)
 {
-   if (!(image->opts & USE_FILE) || (image->opts & USE_STDIO))
+   if (!(image->opts & READ_FILE) || (image->opts & USE_STDIO))
   {
      /* memory or stdio. */
      FILE *f = fopen(image->file_name, "rb");

      if (f != NULL)
      {
-         if (image->opts & USE_FILE)
+         if (image->opts & READ_FILE)
            image->input_file = f;

         else /* memory */
@@ -3069,9 +3175,7 @@ read_one_file(Image *image)

               if (cb > 0)
               {
-#ifndef __COVERITY__
                  if ((unsigned long int)cb <= (size_t)~(size_t)0)
-#endif
                  {
                     png_bytep b = voidcast(png_bytep, malloc((size_t)cb));

@@ -3139,41 +3243,7 @@ write_one_file(Image *output, Image *image, int convert_to_8bit)

   if (image->opts & USE_STDIO)
   {
-#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
-#ifndef __COVERITY__
      FILE *f = tmpfile();
-#else
-      /* Experimental. Coverity says tmpfile() is insecure because it
-       * generates predictable names.
-       *
-       * It is possible to satisfy Coverity by using mkstemp(); however,
-       * any platform supporting mkstemp() undoubtedly has a secure tmpfile()
-       * implementation as well, and doesn't need the fix.  Note that
-       * the fix won't work on platforms that don't support mkstemp().
-       *
-       * https://www.securecoding.cert.org/confluence/display/c/
-       * FIO21-C.+Do+not+create+temporary+files+in+shared+directories
-       * says that most historic implementations of tmpfile() provide
-       * only a limited number of possible temporary file names
-       * (usually 26) before file names are recycled. That article also
-       * provides a secure solution that unfortunately depends upon mkstemp().
-       */
-      char tmpfile[] = "pngstest-XXXXXX";
-      int filedes;
-      FILE *f;
-      umask(0177);
-      filedes = mkstemp(tmpfile);
-      if (filedes < 0)
-        f = NULL;
-      else
-      {
-        f = fdopen(filedes,"w+");
-        /* Hide the filename immediately and ensure that the file does
-         * not exist after the program ends
-         */
-        (void) unlink(tmpfile);
-      }
-#endif

      if (f != NULL)
      {
@@ -3202,14 +3272,10 @@ write_one_file(Image *output, Image *image, int convert_to_8bit)

      else
         return logerror(image, "tmpfile", ": open: ", strerror(errno));
-#else /* SIMPLIFIED_WRITE_STDIO */
-      return logerror(image, "tmpfile", ": open: unsupported", "");
-#endif /* SIMPLIFIED_WRITE_STDIO */
   }

-   else if (image->opts & USE_FILE)
+   else
   {
-#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
      static int counter = 0;
      char name[32];

@@ -3229,51 +3295,6 @@ write_one_file(Image *output, Image *image, int convert_to_8bit)

      else
         return logerror(image, name, ": write failed", "");
-#else /* SIMPLIFIED_WRITE_STDIO */
-      return logerror(image, "stdio", ": open: unsupported", "");
-#endif /* SIMPLIFIED_WRITE_STDIO */
-   }
-
-   else /* use memory */
-   {
-      png_alloc_size_t size;
-
-      if (png_image_write_get_memory_size(image->image, size, convert_to_8bit,
-               image->buffer+16, (png_int_32)image->stride, image->colormap))
-      {
-         /* This is non-fatal but ignoring it was causing serious problems in
-          * the macro to be ignored:
-          */
-         if (size > PNG_IMAGE_PNG_SIZE_MAX(image->image))
-            return logerror(image, "memory", ": PNG_IMAGE_SIZE_MAX wrong", "");
-
-         initimage(output, image->opts, "memory", image->stride_extra);
-         output->input_memory = malloc(size);
-
-         if (output->input_memory != NULL)
-         {
-            output->input_memory_size = size;
-
-            if (png_image_write_to_memory(&image->image, output->input_memory,
-                  &output->input_memory_size, convert_to_8bit, image->buffer+16,
-                  (png_int_32)image->stride, image->colormap))
-            {
-               /* This is also non-fatal but it safes safer to error out anyway:
-                */
-               if (size != output->input_memory_size)
-                  return logerror(image, "memory", ": memory size wrong", "");
-            }
-
-            else
-               return logerror(image, "memory", ": write failed", "");
-         }
-
-         else
-            return logerror(image, "memory", ": out of memory", "");
-      }
-
-      else
-         return logerror(image, "memory", ": get size:", "");
   }

   /* 'output' has an initialized temporary image, read this back in and compare
@@ -3449,8 +3470,6 @@ test_one_file(const char *file_name, format_list *formats, png_uint_32 opts,
   int result;
   Image image;

-   if (!(opts & NO_RESEED))
-      reseed(); /* ensure that the random numbers don't depend on file order */
   newimage(&image);
   initimage(&image, opts, file_name, stride_extra);
   result = read_one_file(&image);
@@ -3488,7 +3507,7 @@ test_one_file(const char *file_name, format_list *formats, png_uint_32 opts,
 int
 main(int argc, char **argv)
 {
-   png_uint_32 opts = FAST_WRITE | STRICT;
+   png_uint_32 opts = FAST_WRITE;
   format_list formats;
   const char *touch = NULL;
   int log_pass = 0;
@@ -3497,17 +3516,11 @@ main(int argc, char **argv)
   int retval = 0;
   int c;

-#if PNG_LIBPNG_VER >= 10700
-      /* This error should not exist in 1.7 or later: */
-      opts |= GBG_ERROR;
-#endif
-
   init_sRGB_to_d();
 #if 0
   init_error_via_linear();
 #endif
   format_init(&formats);
-   reseed(); /* initialize random number seeds */

   for (c=1; c<argc; ++c)
   {
@@ -3522,17 +3535,17 @@ main(int argc, char **argv)
      }
      else if (strcmp(arg, "--file") == 0)
 #        ifdef PNG_STDIO_SUPPORTED
-            opts |= USE_FILE;
+            opts |= READ_FILE;
 #        else
-            return SKIP; /* skipped: no support */
+            return 77; /* skipped: no support */
 #        endif
      else if (strcmp(arg, "--memory") == 0)
-         opts &= ~USE_FILE;
+         opts &= ~READ_FILE;
      else if (strcmp(arg, "--stdio") == 0)
 #        ifdef PNG_STDIO_SUPPORTED
            opts |= USE_STDIO;
 #        else
-            return SKIP; /* skipped: no support */
+            return 77; /* skipped: no support */
 #        endif
      else if (strcmp(arg, "--name") == 0)
         opts &= ~USE_STDIO;
@@ -3558,16 +3571,10 @@ main(int argc, char **argv)
         opts &= ~KEEP_GOING;
      else if (strcmp(arg, "--strict") == 0)
         opts |= STRICT;
-      else if (strcmp(arg, "--nostrict") == 0)
-         opts &= ~STRICT;
      else if (strcmp(arg, "--sRGB-16bit") == 0)
         opts |= sRGB_16BIT;
      else if (strcmp(arg, "--linear-16bit") == 0)
         opts &= ~sRGB_16BIT;
-      else if (strcmp(arg, "--noreseed") == 0)
-         opts |= NO_RESEED;
-      else if (strcmp(arg, "--fault-gbg-warning") == 0)
-         opts |= GBG_ERROR;
      else if (strcmp(arg, "--tmpfile") == 0)
      {
         if (c+1 < argc)
@@ -3581,7 +3588,7 @@ main(int argc, char **argv)
            }

            /* Safe: checked above */
-            strncpy(tmpf, argv[c], sizeof (tmpf)-1);
+            strcpy(tmpf, argv[c]);
         }

         else
@@ -3680,23 +3687,6 @@ main(int argc, char **argv)
   {
      unsigned int in;

-      printf("/* contrib/libtests/pngstest-errors.h\n");
-      printf(" *\n");
-      printf(" * BUILT USING:" PNG_HEADER_VERSION_STRING);
-      printf(" *\n");
-      printf(" * This code is released under the libpng license.\n");
-      printf(" * For conditions of distribution and use, see the disclaimer\n");
-      printf(" * and license in png.h\n");
-      printf(" *\n");
-      printf(" * THIS IS A MACHINE GENERATED FILE: do not edit it directly!\n");
-      printf(" * Instead run:\n");
-      printf(" *\n");
-      printf(" *    pngstest --accumulate\n");
-      printf(" *\n");
-      printf(" * on as many PNG files as possible; at least PNGSuite and\n");
-      printf(" * contrib/libtests/testpngs.\n");
-      printf(" */\n");
-
      printf("static png_uint_16 gpc_error[16/*in*/][16/*out*/][4/*a*/] =\n");
      printf("{\n");
      for (in=0; in<16; ++in)
@@ -3786,7 +3776,6 @@ main(int argc, char **argv)
            putchar('\n');
      }
      printf("};\n");
-      printf("/* END MACHINE GENERATED */\n");
   }

   if (retval == 0 && touch != NULL)
@@ -3824,6 +3813,6 @@ int main(void)
 {
   fprintf(stderr, "pngstest: no read support in libpng, test skipped\n");
   /* So the test is skipped: */
-   return SKIP;
+   return 77;
 }
 #endif /* PNG_SIMPLIFIED_READ_SUPPORTED */
--- a/contrib/libtests/pngunknown.c
+++ b/contrib/libtests/pngunknown.c
@@ -1,8 +1,8 @@

 /* pngunknown.c - test the read side unknown chunk handling
 *
- * Last changed in libpng 1.6.32 [August 24, 2017]
- * Copyright (c) 2015,2017 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.10 [March 6, 2014]
+ * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by John Cunningham Bowler
 *
 * This code is released under the libpng license.
@@ -30,21 +30,10 @@
 #  include "../../png.h"
 #endif

-/* 1.6.1 added support for the configure test harness, which uses 77 to indicate
- * a skipped test, in earlier versions we need to succeed on a skipped test, so:
- */
-#if PNG_LIBPNG_VER >= 10601 && defined(HAVE_CONFIG_H)
-#  define SKIP 77
-#else
-#  define SKIP 0
-#endif
-
-
 /* Since this program tests the ability to change the unknown chunk handling
 * these must be defined:
 */
 #if defined(PNG_SET_UNKNOWN_CHUNKS_SUPPORTED) &&\
-   defined(PNG_STDIO_SUPPORTED) &&\
   defined(PNG_READ_SUPPORTED)

 /* One of these must be defined to allow us to find out what happened.  It is
@@ -114,7 +103,6 @@ typedef png_byte *png_const_bytep;
 #define png_PLTE PNG_U32( 80,  76,  84,  69)
 #define png_bKGD PNG_U32( 98,  75,  71,  68)
 #define png_cHRM PNG_U32( 99,  72,  82,  77)
-#define png_eXIf PNG_U32(101,  88,  73, 102) /* registered July 2017 */
 #define png_fRAc PNG_U32(102,  82,  65,  99) /* registered, not defined */
 #define png_gAMA PNG_U32(103,  65,  77,  65)
 #define png_gIFg PNG_U32(103,  73,  70, 103)
@@ -211,13 +199,6 @@ static struct
         1,
 #     endif
      1,  START, 0 },
-   { "eXIf", PNG_INFO_eXIf, png_eXIf,
-#     ifdef PNG_READ_eXIf_SUPPORTED
-         0,
-#     else
-         1,
-#     endif
-      1,  END, 0 },
   { "gAMA", PNG_INFO_gAMA, png_gAMA,
 #     ifdef PNG_READ_gAMA_SUPPORTED
         0,
@@ -382,7 +363,7 @@ ancillary(const char *name)
   return PNG_CHUNK_ANCILLARY(PNG_U32(name[0], name[1], name[2], name[3]));
 }

-#ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
 static int
 ancillaryb(const png_byte *name)
 {
@@ -486,7 +467,7 @@ get_valid(display *d, png_infop info_ptr)
      png_textp text;
      png_uint_32 ntext = png_get_text(d->png_ptr, info_ptr, &text, NULL);

-      while (ntext > 0) switch (text[--ntext].compression)
+      while (ntext-- > 0) switch (text[ntext].compression)
      {
         case -1:
            flags |= PNG_INFO_tEXt;
@@ -573,7 +554,7 @@ read_callback(png_structp pp, png_unknown_chunkp pc)
   /* However if there is no support to store unknown chunks don't ask libpng to
    * do it; there will be an png_error.
    */
-#  ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+#  ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
      return discard;
 #  else
      return 1; /*handled; discard*/
@@ -581,7 +562,7 @@ read_callback(png_structp pp, png_unknown_chunkp pc)
 }
 #endif /* READ_USER_CHUNKS_SUPPORTED */

-#ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
 static png_uint_32
 get_unknown(display *d, png_infop info_ptr, int after_IDAT)
 {
@@ -622,7 +603,7 @@ get_unknown(display *d, png_infop info_ptr, int after_IDAT)
                  ++(d->error_count);
                  break;
               }
-               /* FALLTHROUGH */ /* (safe) */
+               /* FALL THROUGH (safe) */
            case PNG_HANDLE_CHUNK_ALWAYS:
               break;
         }
@@ -634,7 +615,7 @@ get_unknown(display *d, png_infop info_ptr, int after_IDAT)

   return flags;
 }
-#else /* SAVE_UNKNOWN_CHUNKS */
+#else
 static png_uint_32
 get_unknown(display *d, png_infop info_ptr, int after_IDAT)
   /* Otherwise this will return the cached values set by any user callback */
@@ -653,8 +634,8 @@ get_unknown(display *d, png_infop info_ptr, int after_IDAT)
       * a check to ensure the logic is correct.
       */
 #     error No store support and no user chunk support, this will not work
-#  endif /* READ_USER_CHUNKS */
-#endif /* SAVE_UNKNOWN_CHUNKS */
+#  endif
+#endif

 static int
 check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
@@ -741,17 +722,11 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
                   * in this case, so we just check the arguments!  This could
                   * be improved in the future by using the read callback.
                   */
-#                 if PNG_LIBPNG_VER >= 10700 &&\
-                     !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
-                     if (option < PNG_HANDLE_CHUNK_IF_SAFE)
-#                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
-                  {
-                     png_byte name[5];
+                  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;
-                  }
+                  memcpy(name, chunk_info[chunk].name, 5);
+                  png_set_keep_unknown_chunks(d->png_ptr, option, name, 1);
+                  chunk_info[chunk].keep = option;
                  continue;
               }

@@ -760,12 +735,7 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
            case 7: /* default */
               if (memcmp(argv[i], "default", 7) == 0)
               {
-#                 if PNG_LIBPNG_VER >= 10700 &&\
-                     !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
-                     if (option < PNG_HANDLE_CHUNK_IF_SAFE)
-#                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
-                     png_set_keep_unknown_chunks(d->png_ptr, option, NULL, 0);
-
+                  png_set_keep_unknown_chunks(d->png_ptr, option, NULL, 0);
                  d->keep = option;
                  continue;
               }
@@ -775,12 +745,7 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
            case 3: /* all */
               if (memcmp(argv[i], "all", 3) == 0)
               {
-#                 if PNG_LIBPNG_VER >= 10700 &&\
-                     !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
-                     if (option < PNG_HANDLE_CHUNK_IF_SAFE)
-#                 endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
-                     png_set_keep_unknown_chunks(d->png_ptr, option, NULL, -1);
-
+                  png_set_keep_unknown_chunks(d->png_ptr, option, NULL, -1);
                  d->keep = option;

                  for (chunk = 0; chunk < NINFO; ++chunk)
@@ -1020,20 +985,6 @@ perform_one_test(FILE *fp, int argc, const char **argv,

   def = check(fp, argc, argv, flags[1], d, set_callback);

-   /* If IDAT is being handled as unknown the image read is skipped and all the
-    * IDATs after the first end up in the end info struct, so in this case add
-    * IDAT to the list of unknowns.  (Do this after 'check' above sets the
-    * chunk_info 'keep' fields.)
-    *
-    * Note that the flag setting has to be in the 'known' field to avoid
-    * triggering the consistency check below and the flag must only be set if
-    * there are multiple IDATs, so if the check above did find an unknown IDAT
-    * after IDAT.
-    */
-   if (chunk_info[0/*IDAT*/].keep != PNG_HANDLE_CHUNK_AS_DEFAULT &&
-       (flags[1][3] & PNG_INFO_IDAT) != 0)
-      flags[0][2] |= PNG_INFO_IDAT;
-
   /* 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
@@ -1098,7 +1049,7 @@ static const char *standard_tests[] =
 "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", "eXIf=save", 0,
+   "sBIT=save", "sRGB=save", 0,
 0/*end*/
 };

@@ -1278,7 +1229,7 @@ main(void)
   fprintf(stderr,
      " test ignored: no support to find out about unknown chunks\n");
   /* So the test is skipped: */
-   return SKIP;
+   return 77;
 }
 #endif /* READ_USER_CHUNKS || SAVE_UNKNOWN_CHUNKS */

@@ -1289,6 +1240,6 @@ main(void)
   fprintf(stderr,
      " test ignored: no support to modify unknown chunk handling\n");
   /* So the test is skipped: */
-   return SKIP;
+   return 77;
 }
-#endif /* SET_UNKNOWN_CHUNKS && READ*/
+#endif /* SET_UNKNOWN_CHUNKS && READ */
--- a/contrib/libtests/pngvalid.c
+++ b/contrib/libtests/pngvalid.c
--- a/contrib/libtests/readpng.c
+++ b/contrib/libtests/readpng.c
@@ -62,7 +62,6 @@ read_png(FILE *fp)
   {
      png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);

-      /* Failure to initialize these is harmless */
      row = malloc(rowbytes);
      display = malloc(rowbytes);

@@ -71,12 +70,7 @@ read_png(FILE *fp)

      {
         png_uint_32 height = png_get_image_height(png_ptr, info_ptr);
-#        ifdef PNG_READ_INTERLACING_SUPPORTED
-            int passes = png_set_interlace_handling(png_ptr);
-#        else /* !READ_INTERLACING */
-            int passes = png_get_interlace_type(png_ptr, info_ptr) ==
-               PNG_INTERLACE_ADAM7 ? PNG_INTERLACE_ADAM7_PASSES : 1;
-#        endif /* !READ_INTERLACING */
+         int passes = png_set_interlace_handling(png_ptr);
         int pass;

         png_start_read_image(png_ptr);
@@ -85,11 +79,6 @@ read_png(FILE *fp)
         {
            png_uint_32 y = height;

-#           ifndef PNG_READ_INTERLACING_SUPPORTED
-               if (passes == PNG_INTERLACE_ADAM7_PASSES)
-                  y = PNG_PASS_ROWS(y, pass);
-#           endif /* READ_INTERLACING */
-
            /* NOTE: this trashes the row each time; interlace handling won't
             * work, but this avoids memory thrashing for speed testing.
             */
--- a/contrib/libtests/tarith.c
+++ b/contrib/libtests/tarith.c
@@ -634,7 +634,7 @@ int validation_muldiv(int count, int argc, char **argv)
   {
      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
+       * hold 64 bits or more, if floating point is used a 64 bit or
       * better mantissa is required.
       */
      long long int fp, fpround;
@@ -721,7 +721,7 @@ int validation_muldiv(int count, int argc, char **argv)
   }
   while (--count > 0);

-   printf("%d tests including %d overflows, %d passed, %d failed (%d 64-bit "
+   printf("%d tests including %d overflows, %d passed, %d failed (%d 64 bit "
      "errors)\n", tested, overflow, passed, error, error64);
   return 0;
 }
@@ -799,13 +799,13 @@ int validation_gamma(int argc, char **argv)
         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",
+            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);
+         printf("maximum 8 bit log error = %f\n", maxerr);

      maxerr = 0;
      for (i=0; i<65536; ++i)
@@ -821,14 +821,14 @@ int validation_gamma(int argc, char **argv)
         {
            if (error > .68) /* By experiment error is less than .68 */
            {
-               fprintf(stderr, "16-bit log error: %d: got %u, expected %f"
+               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);
+         printf("maximum 16 bit log error = %f\n", maxerr);

      /* Now exponentiations. */
      maxerr = 0;
@@ -841,13 +841,13 @@ int validation_gamma(int argc, char **argv)
            maxerr = fabs(error);
         if (fabs(error) > 1883) /* By experiment. */
         {
-            fprintf(stderr, "32-bit exp error: %d: got %u, expected %f"
+            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);
+         printf("maximum 32 bit exp error = %f\n", maxerr);

      maxerr = 0;
      for (i=0; i<=0xfffff; ++i)
@@ -859,13 +859,13 @@ int validation_gamma(int argc, char **argv)
            maxerr = fabs(error);
         if (fabs(error) > .50002) /* By experiment */
         {
-            fprintf(stderr, "8-bit exp error: %d: got %u, expected %f"
+            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);
+         printf("maximum 8 bit exp error = %f\n", maxerr);

      maxerr = 0;
      for (i=0; i<=0xfffff; ++i)
@@ -877,13 +877,13 @@ int validation_gamma(int argc, char **argv)
            maxerr = fabs(error);
         if (fabs(error) > .524) /* By experiment */
         {
-            fprintf(stderr, "16-bit exp error: %d: got %u, expected %f"
+            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);
+         printf("maximum 16 bit exp error = %f\n", maxerr);
   } /* !onlygamma */

   /* Test the overall gamma correction. */
@@ -913,7 +913,7 @@ int validation_gamma(int argc, char **argv)
      }

      if (!silent)
-         printf("gamma %f: maximum 8-bit error %f\n", g, maxerr);
+         printf("gamma %f: maximum 8 bit error %f\n", g, maxerr);

      maxerr = 0;
      for (j=0; j<65536; ++j)
@@ -932,7 +932,7 @@ int validation_gamma(int argc, char **argv)
      }

      if (!silent)
-         printf("gamma %f: maximum 16-bit error %f\n", g, maxerr);
+         printf("gamma %f: maximum 16 bit error %f\n", g, maxerr);
   }

   return 0;
--- a/contrib/libtests/timepng.c
+++ b/contrib/libtests/timepng.c
@@ -1,8 +1,8 @@
 /* timepng.c
 *
- * Copyright (c) 2013,2016 John Cunningham Bowler
+ * Copyright (c) 2013 John Cunningham Bowler
 *
- * Last changed in libpng 1.6.22 [May 26, 2016]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -10,17 +10,15 @@
 *
 * 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 or by image (possibly with transforms in the latter
- * case).  The only output is a time as a floating point number of seconds with
- * 9 decimal digits.
+ * 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 <errno.h>
-#include <limits.h>

 #include <time.h>

@@ -37,73 +35,36 @@
 #  include "../../png.h"
 #endif

-/* The following is to support direct compilation of this file as C++ */
-#ifdef __cplusplus
-#  define voidcast(type, value) static_cast<type>(value)
-#else
-#  define voidcast(type, value) (value)
-#endif /* __cplusplus */
-
-/* 'CLOCK_PROCESS_CPUTIME_ID' is one of the clock timers for clock_gettime.  It
- * need not be supported even when clock_gettime is available.  It returns the
- * 'CPU' time the process has consumed.  'CPU' time is assumed to include time
- * when the CPU is actually blocked by a pending cache fill but not time
- * waiting for page faults.  The attempt is to get a measure of the actual time
- * the implementation takes to read a PNG ignoring the potentially very large IO
- * overhead.
- */
-#if defined (CLOCK_PROCESS_CPUTIME_ID) && defined(PNG_STDIO_SUPPORTED) &&\
-    defined(PNG_EASY_ACCESS_SUPPORTED) &&\
-    (PNG_LIBPNG_VER >= 10700 ? defined(PNG_READ_PNG_SUPPORTED) :\
-     defined (PNG_SEQUENTIAL_READ_SUPPORTED) &&\
-     defined(PNG_INFO_IMAGE_SUPPORTED))
-
-typedef struct
+static int read_png(FILE *fp)
 {
-   FILE *input;
-   FILE *output;
-}  io_data;
-
-static PNG_CALLBACK(void, read_and_copy,
-      (png_structp png_ptr, png_bytep buffer, png_size_t cb))
-{
-   io_data *io = (io_data*)png_get_io_ptr(png_ptr);
-
-   if (fread(buffer, cb, 1, io->input) != 1)
-      png_error(png_ptr, strerror(errno));
-
-   if (fwrite(buffer, cb, 1, io->output) != 1)
-   {
-      perror("temporary file");
-      fprintf(stderr, "temporary file PNG write failed\n");
-      exit(1);
-   }
-}
-
-static void read_by_row(png_structp png_ptr, png_infop info_ptr,
-      FILE *write_ptr, FILE *read_ptr)
-{
-   /* These don't get freed on error, this is fine; the program immediately
-    * exits.
-    */
+   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;
-   io_data io_copy;

-   if (write_ptr != NULL)
+   if (png_ptr == NULL)
+      return 0;
+
+   if (setjmp(png_jmpbuf(png_ptr)))
   {
-      /* Set up for a copy to the temporary file: */
-      io_copy.input = read_ptr;
-      io_copy.output = write_ptr;
-      png_set_read_fn(png_ptr, &io_copy, read_and_copy);
+      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 = voidcast(png_bytep,malloc(rowbytes));
-      display = voidcast(png_bytep,malloc(rowbytes));
+      row = malloc(rowbytes);
+      display = malloc(rowbytes);

      if (row == NULL || display == NULL)
         png_error(png_ptr, "OOM allocating row buffers");
@@ -120,8 +81,7 @@ static void read_by_row(png_structp png_ptr, png_infop info_ptr,
            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 and is
-             * somewhat representative of an application that works row-by-row.
+             * work, but this avoids memory thrashing for speed testing.
             */
            while (y-- > 0)
               png_read_row(png_ptr, row, display);
@@ -131,51 +91,9 @@ static void read_by_row(png_structp png_ptr, png_infop info_ptr,

   /* Make sure to read to the end of the file: */
   png_read_end(png_ptr, info_ptr);
-
-   /* Free this up: */
+   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
   free(row);
   free(display);
-}
-
-static PNG_CALLBACK(void, no_warnings, (png_structp png_ptr,
-         png_const_charp warning))
-{
-   (void)png_ptr;
-   (void)warning;
-}
-
-static int read_png(FILE *fp, png_int_32 transforms, FILE *write_file)
-{
-   png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,
-         no_warnings);
-   png_infop info_ptr = NULL;
-
-   if (png_ptr == NULL)
-      return 0;
-
-   if (setjmp(png_jmpbuf(png_ptr)))
-   {
-      png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
-      return 0;
-   }
-
-#  ifdef PNG_BENIGN_ERRORS_SUPPORTED
-      png_set_benign_errors(png_ptr, 1/*allowed*/);
-#  endif
-   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");
-
-   if (transforms < 0)
-      read_by_row(png_ptr, info_ptr, write_file, fp);
-
-   else
-      png_read_png(png_ptr, info_ptr, transforms, NULL/*params*/);
-
-   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
   return 1;
 }

@@ -190,7 +108,7 @@ static int mytime(struct timespec *t)
   return 0;
 }

-static int perform_one_test(FILE *fp, int nfiles, png_int_32 transforms)
+static int perform_one_test(FILE *fp, int nfiles)
 {
   int i;
   struct timespec before, after;
@@ -202,7 +120,7 @@ static int perform_one_test(FILE *fp, int nfiles, png_int_32 transforms)
   {
      for (i=0; i<nfiles; ++i)
      {
-         if (read_png(fp, transforms, NULL/*write*/))
+         if (read_png(fp))
         {
            if (ferror(fp))
            {
@@ -266,343 +184,120 @@ static int add_one_file(FILE *fp, char *name)

   if (ip != NULL)
   {
-      /* Read the file using libpng; this detects errors and also deals with
-       * files which contain data beyond the end of the file.
-       */
-      int ok = 0;
-      fpos_t pos;
-
-      if (fgetpos(fp, &pos))
+      int ch;
+      for (;;)
      {
-         /* Fatal error reading the start: */
-         perror("temporary file");
-         fprintf(stderr, "temporary file fgetpos error\n");
-         exit(1);
+         ch = getc(ip);
+         if (ch == EOF) break;
+         putc(ch, fp);
      }

-      if (read_png(ip, -1/*by row*/, fp/*output*/))
+      if (ferror(ip))
      {
-         if (ferror(ip))
-         {
-            perror(name);
-            fprintf(stderr, "%s: read error\n", name);
-         }
-
-         else
-            ok = 1; /* read ok */
+         perror(name);
+         fprintf(stderr, "%s: read error\n", name);
+         return 0;
      }

-      else
-         fprintf(stderr, "%s: file not added\n", name);
-
      (void)fclose(ip);

-      /* An error in the output is fatal; exit immediately: */
      if (ferror(fp))
      {
         perror("temporary file");
         fprintf(stderr, "temporary file write error\n");
-         exit(1);
-      }
-
-      if (ok)
-         return 1;
-
-      /* Did not read the file successfully, simply rewind the temporary
-       * file.  This must happen after the ferror check above to avoid clearing
-       * the error.
-       */
-      if (fsetpos(fp, &pos))
-      {
-         perror("temporary file");
-         fprintf(stderr, "temporary file fsetpos error\n");
-         exit(1);
+         return 0;
      }
   }

   else
   {
-      /* file open error: */
      perror(name);
      fprintf(stderr, "%s: open failed\n", name);
+      return 0;
   }

-   return 0; /* file not added */
-}
-
-static void
-usage(FILE *fp)
-{
-   if (fp != NULL) fclose(fp);
-
-   fprintf(stderr,
-"Usage:\n"
-" timepng --assemble <assembly> {files}\n"
-"  Read the files into <assembly>, output the count.  Options are ignored.\n"
-" timepng --dissemble <assembly> <count> [options]\n"
-"  Time <count> files from <assembly>, additional files may not be given.\n"
-" Otherwise:\n"
-"  Read the files into a temporary file and time the decode\n"
-"Transforms:\n"
-"  --by-image: read by image with png_read_png\n"
-"  --<transform>: implies by-image, use PNG_TRANSFORM_<transform>\n"
-"  Otherwise: read by row using png_read_row (to a single row buffer)\n"
-   /* ISO C90 string length max 509 */);fprintf(stderr,
-"{files}:\n"
-"  PNG files to copy into the assembly and time.  Invalid files are skipped\n"
-"  with appropriate error messages.  If no files are given the list of files\n"
-"  is read from stdin with each file name terminated by a newline\n"
-"Output:\n"
-"  For --assemble the output is the name of the assembly file followed by the\n"
-"  count of the files it contains; the arguments for --dissemble.  Otherwise\n"
-"  the output is the total decode time in seconds.\n");
-
-   exit(99);
+   return 1;
 }

 int main(int argc, char **argv)
 {
   int ok = 0;
-   int err = 0;
-   int nfiles = 0;
-   int transforms = -1; /* by row */
-   const char *assembly = NULL;
-   FILE *fp;
+   FILE *fp = tmpfile();

-   if (argc > 2 && strcmp(argv[1], "--assemble") == 0)
+   if (fp != NULL)
   {
-      /* Just build the test file, argv[2] is the file name. */
-      assembly = argv[2];
-      fp = fopen(assembly, "wb");
-      if (fp == NULL)
+      int err = 0;
+      int nfiles = 0;
+
+      if (argc > 1)
      {
-         perror(assembly);
-         fprintf(stderr, "timepng --assemble %s: could not open for write\n",
-               assembly);
-         usage(NULL);
-      }
+         int i;

-      argv += 2;
-      argc -= 2;
-   }
-
-   else if (argc > 3 && strcmp(argv[1], "--dissemble") == 0)
-   {
-      fp = fopen(argv[2], "rb");
-
-      if (fp == NULL)
-      {
-         perror(argv[2]);
-         fprintf(stderr, "timepng --dissemble %s: could not open for read\n",
-               argv[2]);
-         usage(NULL);
-      }
-
-      nfiles = atoi(argv[3]);
-      if (nfiles <= 0)
-      {
-         fprintf(stderr,
-               "timepng --dissemble <file> <count>: %s is not a count\n",
-               argv[3]);
-         exit(99);
-      }
-#ifdef __COVERITY__
-      else
-      {
-         nfiles &= PNG_UINT_31_MAX;
-      }
-#endif
-
-      argv += 3;
-      argc -= 3;
-   }
-
-   else /* Else use a temporary file */
-   {
-#ifndef __COVERITY__
-      fp = tmpfile();
-#else
-      /* Experimental. Coverity says tmpfile() is insecure because it
-       * generates predictable names.
-       *
-       * It is possible to satisfy Coverity by using mkstemp(); however,
-       * any platform supporting mkstemp() undoubtedly has a secure tmpfile()
-       * implementation as well, and doesn't need the fix.  Note that
-       * the fix won't work on platforms that don't support mkstemp().
-       *
-       * https://www.securecoding.cert.org/confluence/display/c/
-       * FIO21-C.+Do+not+create+temporary+files+in+shared+directories
-       * says that most historic implementations of tmpfile() provide
-       * only a limited number of possible temporary file names
-       * (usually 26) before file names are recycled. That article also
-       * provides a secure solution that unfortunately depends upon mkstemp().
-       */
-      char tmpfile[] = "timepng-XXXXXX";
-      int filedes;
-      umask(0177);
-      filedes = mkstemp(tmpfile);
-      if (filedes < 0)
-        fp = NULL;
-      else
-      {
-        fp = fdopen(filedes,"w+");
-        /* Hide the filename immediately and ensure that the file does
-         * not exist after the program ends
-         */
-        (void) unlink(tmpfile);
-      }
-#endif
-
-      if (fp == NULL)
-      {
-         perror("tmpfile");
-         fprintf(stderr, "timepng: could not open the temporary file\n");
-         exit(1); /* not a user error */
-      }
-   }
-
-   /* Handle the transforms: */
-   while (argc > 1 && argv[1][0] == '-' && argv[1][1] == '-')
-   {
-      const char *opt = *++argv + 2;
-
-      --argc;
-
-      /* Transforms turn on the by-image processing and maybe set some
-       * transforms:
-       */
-      if (transforms == -1)
-         transforms = PNG_TRANSFORM_IDENTITY;
-
-      if (strcmp(opt, "by-image") == 0)
-      {
-         /* handled above */
-      }
-
-#        define OPT(name) else if (strcmp(opt, #name) == 0)\
-         transforms |= PNG_TRANSFORM_ ## name
-
-      OPT(STRIP_16);
-      OPT(STRIP_ALPHA);
-      OPT(PACKING);
-      OPT(PACKSWAP);
-      OPT(EXPAND);
-      OPT(INVERT_MONO);
-      OPT(SHIFT);
-      OPT(BGR);
-      OPT(SWAP_ALPHA);
-      OPT(SWAP_ENDIAN);
-      OPT(INVERT_ALPHA);
-      OPT(STRIP_FILLER);
-      OPT(STRIP_FILLER_BEFORE);
-      OPT(STRIP_FILLER_AFTER);
-      OPT(GRAY_TO_RGB);
-      OPT(EXPAND_16);
-      OPT(SCALE_16);
-
-      else
-      {
-         fprintf(stderr, "timepng %s: unrecognized transform\n", opt);
-         usage(fp);
-      }
-   }
-
-   /* Handle the files: */
-   if (argc > 1 && nfiles > 0)
-      usage(fp); /* Additional files not valid with --dissemble */
-
-   else if (argc > 1)
-   {
-      int i;
-
-      for (i=1; i<argc; ++i)
-      {
-         if (nfiles == INT_MAX)
+         for (i=1; i<argc; ++i)
         {
-            fprintf(stderr, "%s: skipped, too many files\n", argv[i]);
-            break;
-         }
+            if (add_one_file(fp, argv[i]))
+               ++nfiles;

-         else if (add_one_file(fp, argv[i]))
-            ++nfiles;
-      }
-   }
-
-   else if (nfiles == 0) /* Read from stdin withoout --dissemble */
-   {
-      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 (nfiles == INT_MAX)
+            else
            {
-               fprintf(stderr, "%s: skipped, too many files\n", filename);
+               err = 1;
               break;
            }
-
-            else if (add_one_file(fp, filename))
-               ++nfiles;
-         }
-
-         else
-         {
-            fprintf(stderr, "timepng: file name too long: ...%s\n",
-               filename+len-32);
-            err = 1;
-            break;
         }
      }

-      if (ferror(stdin))
+      else
      {
-         fprintf(stderr, "timepng: stdin: read error\n");
-         err = 1;
-      }
-   }
+         char filename[FILENAME_MAX+1];

-   /* Perform the test, or produce the --assemble output: */
-   if (!err)
-   {
-      if (nfiles > 0)
-      {
-         if (assembly != NULL)
+         while (fgets(filename, FILENAME_MAX+1, stdin))
         {
-            if (fflush(fp) && !ferror(fp) && fclose(fp))
+            size_t len = strlen(filename);
+
+            if (filename[len-1] == '\n')
            {
-               perror(assembly);
-               fprintf(stderr, "%s: close failed\n", assembly);
+               filename[len-1] = 0;
+               if (add_one_file(fp, filename))
+                  ++nfiles;
+
+               else
+               {
+                  err = 1;
+                  break;
+               }
            }

            else
            {
-               printf("%s %d\n", assembly, nfiles);
-               fflush(stdout);
-               ok = !ferror(stdout);
+               fprintf(stderr, "timepng: truncated file name ...%s\n",
+                  filename+len-32);
+               err = 1;
+               break;
            }
         }

-         else
+         if (ferror(stdin))
         {
-            ok = perform_one_test(fp, nfiles, transforms);
-            (void)fclose(fp);
+            fprintf(stderr, "timepng: stdin: read error\n");
+            err = 1;
         }
      }

-      else
-         usage(fp);
+      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
-      (void)fclose(fp);
+      fprintf(stderr, "timepng: could not open temporary file\n");

   /* Exit code 0 on success. */
   return ok == 0;
 }
-#else /* !sufficient support */
-int main(void) { return 77; }
-#endif /* !sufficient support */
--- a/contrib/mips-msa/README
+++ b/contrib/mips-msa/README
@@ -1,83 +0,0 @@
-OPERATING SYSTEM SPECIFIC MIPS MSA DETECTION
--------------------------------------------
-
-Detection of the ability to execute MIPS MSA on an MIPS processor requires
-operating system support.  (The information is not available in user mode.)
-
-HOW TO USE THIS
---------------
-
-This directory contains C code fragments that can be included in mips/mips_init.c
-by setting the macro PNG_MIPS_MSA_FILE to the file name in "" or <> at build
-time.  This setting is not recorded in pnglibconf.h and can be changed simply by
-rebuilding mips/msa_init.o with the required macro definition.
-
-For any of this code to be used the MIPS MSA code must be enabled and run time
-checks must be supported.  I.e.:
-
-#if PNG_MIPS_MSA_OPT > 0
-#ifdef PNG_MIPS_MSA_CHECK_SUPPORTED
-
-This is done in a 'configure' build by passing configure the argument:
-
-   --enable-mips-msa=check
-
-Apart from the basic Linux implementation in contrib/mips-msa/linux.c this code
-is unsupported.  That means that it is not even compiled on a regular basis and
-may be broken in any given minor release.
-
-FILE FORMAT
-----------
-
-Each file documents its testing status as of the last time it was tested (which
-may have been a long time ago):
-
-STATUS: one of:
-   SUPPORTED: This indicates that the file is included in the regularly
-         performed test builds and bugs are fixed when discovered.
-   COMPILED: This indicates that the code did compile at least once.  See the
-         more detailed description for the extent to which the result was
-         successful.
-   TESTED: This means the code was fully compiled into the libpng test programs
-         and these were run at least once.
-
-BUG REPORTS: an email address to which to send reports of problems
-
-The file is a fragment of C code. It should not define any 'extern' symbols;
-everything should be static.  It must define the function:
-
-static int png_have_msa(png_structp png_ptr);
-
-That function must return 1 if MIPS MSA instructions are supported, 0 if not.
-It must not execute png_error unless it detects a bug.  A png_error will prevent
-the reading of the PNG and in the future, writing too.
-
-BUG REPORTS
-----------
-
-If you mail a bug report for any file that is not SUPPORTED there may only be
-limited response.  Consider fixing it and sending a patch to fix the problem -
-this is more likely to result in action.
-
-CONTRIBUTIONS
-------------
-
-You may send contributions of new implementations to
-png-mng-implement@sourceforge.net.  Please write code in strict C90 C where
-possible.  Obviously OS dependencies are to be expected.  If you submit code you
-must have the authors permission and it must have a license that is acceptable
-to the current maintainer; in particular that license must permit modification
-and redistribution.
-
-Please try to make the contribution a single file and give the file a clear and
-unambiguous name that identifies the target OS.  If multiple files really are
-required put them all in a sub-directory.
-
-You must also be prepared to handle bug reports from users of the code, either
-by joining the png-mng-implement mailing list or by providing an email for the
-"BUG REPORTS" entry or both.  Please make sure that the header of the file
-contains the STATUS and BUG REPORTS fields as above.
-
-Please list the OS requirements as precisely as possible.  Ideally you should
-also list the environment in which the code has been tested and certainly list
-any environments where you suspect it might not work.
--- a/contrib/mips-msa/linux.c
+++ b/contrib/mips-msa/linux.c
@@ -1,64 +0,0 @@
-/* contrib/mips-msa/linux.c
- *
- * Copyright (c) 2016 Glenn Randers-Pehrson
- * Written by Mandar Sahastrabuddhe, 2016.
- * Last changed in libpng 1.6.25beta03 [August 29, 2016]
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * SEE contrib/mips-msa/README before reporting bugs
- *
- * STATUS: SUPPORTED
- * BUG REPORTS: png-mng-implement@sourceforge.net
- *
- * png_have_msa implemented for Linux by reading the widely available
- * pseudo-file /proc/cpuinfo.
- *
- * This code is strict ANSI-C and is probably moderately portable; it does
- * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
- */
-
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-
-static int
-png_have_msa(png_structp png_ptr)
-{
-   FILE *f = fopen("/proc/cpuinfo", "rb");
-
-   char *string = "msa";
-   char word[10];
-
-   if (f != NULL)
-   {
-      while(!feof(f))
-      {
-         int ch = fgetc(f);
-         static int i = 0;
-
-         while(!(ch <= 32))
-         {
-            word[i++] = ch;
-            ch = fgetc(f);
-         }
-
-         int val = strcmp(string, word);
-
-         if (val == 0)
-            return 1;
-
-         i = 0;
-         memset(word, 0, 10);
-      }
-
-      fclose(f);
-   }
-#ifdef PNG_WARNINGS_SUPPORTED
-   else
-      png_warning(png_ptr, "/proc/cpuinfo open failed");
-#endif
-   return 0;
-}
--- a/contrib/oss-fuzz/Dockerfile
+++ b/contrib/oss-fuzz/Dockerfile
@@ -1,24 +0,0 @@
-# Copyright 2016 Google Inc.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-################################################################################
-
-FROM gcr.io/oss-fuzz-base/base-builder
-MAINTAINER glennrp@gmail.com
-RUN apt-get update && apt-get install -y make autoconf automake libtool zlib1g-dev
-
-RUN git clone --depth 1 https://github.com/glennrp/libpng.git
-RUN (cd libpng; git log | head -1)
-WORKDIR libpng
-COPY build.sh $SRC/
--- a/contrib/oss-fuzz/README.txt
+++ b/contrib/oss-fuzz/README.txt
@@ -1,37 +0,0 @@
-Last changed in libpng 1.6.33 [September 28, 2017]
-Copyright (c) 2017 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
-
-Files in this directory are used by the oss-fuzz project
-(https://github.com/google/oss-fuzz/tree/master/projects/libpng).
-for "fuzzing" libpng.
-
-They were licensed by Google Inc, using the BSD-like Chromium license,
-which may be found at https://cs.chromium.org/chromium/src/LICENSE, or, if
-noted in the source, under the Apache-2.0 license, which may
-be found at http://www.apache.org/licenses/LICENSE-2.0 .
-If they have been modified, the derivatives are copyright Glenn Randers-Pehrson
-and are released under the same licenses as the originals.  Several of
-the original files (libpng_read_fuzzer.options, png.dict, project.yaml)
-had no licensing information; we assumed that these were under the Chromium
-license. Any new files are released under the libpng license (see png.h).
-
-The files are
-                            Original
- Filename                   or derived   Copyright          License
- =========================  ==========   ================   ==========
- Dockerfile*                derived      2017, Glenn R-P    Apache 2.0
- build.sh*                  derived      2017, Glenn R-P    Apache 2.0
- libpng_read_fuzzer.cc      derived      2017, Glenn R-P    Chromium
- libpng_read_fuzzer.options original     2015, Chrome Devs  Chromium
- png.dict                   original     2015, Chrome Devs  Chromium
- README.txt (this file)     original     2017, Glenn R-P    libpng
-
- * Dockerfile and build.sh are copies of the files used by oss-fuzz.
-   png.dict and libpng_read_fuzzer.* are the actual files used by oss-fuzz,
-   which retrieves them from the libpng repository at Github.
-
-To do: exercise the progressive reader and the png encoder.
--- a/contrib/oss-fuzz/build.sh
+++ b/contrib/oss-fuzz/build.sh
@@ -1,50 +0,0 @@
-#!/bin/bash -eu
-# Copyright 2017 Glenn Randers-Pehrson
-# Copyright 2016 Google Inc.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-# Last changed in libpng 1.6.33 [September 28, 2017]
-#
-# Revisions by Glenn Randers-Pehson, 2017:
-# 1. Build only the library, not the tools (changed "make -j$(nproc) all" to
-#     "make -j$(nproc) libpng16.la").
-# 2. Disabled WARNING and WRITE options in pnglibconf.dfa.
-################################################################################
-
-# Disable logging via library build configuration control.
-cat scripts/pnglibconf.dfa | \
-  sed -e "s/option STDIO/option STDIO disabled/" \
-      -e "s/option WARNING /option WARNING disabled/" \
-      -e "s/option WRITE enables WRITE_INT_FUNCTIONS/option WRITE disabled/" \
-> scripts/pnglibconf.dfa.temp
-mv scripts/pnglibconf.dfa.temp scripts/pnglibconf.dfa
-
-# build the library.
-autoreconf -f -i
-./configure
-make -j$(nproc) clean
-make -j$(nproc) libpng16.la
-
-# build libpng_read_fuzzer.
-$CXX $CXXFLAGS -std=c++11 -I. \
-     $SRC/libpng/contrib/oss-fuzz/libpng_read_fuzzer.cc \
-     -o $OUT/libpng_read_fuzzer \
-     -lFuzzingEngine .libs/libpng16.a -lz
-
-# add seed corpus.
-find $SRC/libpng -name "*.png" | grep -v crashers | \
-     xargs zip $OUT/libpng_read_fuzzer_seed_corpus.zip
-
-cp $SRC/libpng/contrib/oss-fuzz/*.dict \
-     $SRC/libpng/contrib/oss-fuzz/*.options $OUT/
--- a/contrib/oss-fuzz/libpng_read_fuzzer.cc
+++ b/contrib/oss-fuzz/libpng_read_fuzzer.cc
@@ -1,180 +0,0 @@
-
-// libpng_read_fuzzer.cc
-// Copyright 2017 Glenn Randers-Pehrson
-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that may
-// be found in the LICENSE file https://cs.chromium.org/chromium/src/LICENSE
-
-// Last changed in libpng 1.6.32 [August 24, 2017]
-
-// The modifications in 2017 by Glenn Randers-Pehrson include
-// 1. addition of a PNG_CLEANUP macro,
-// 2. setting the option to ignore ADLER32 checksums,
-// 3. adding "#include <string.h>" which is needed on some platforms
-//    to provide memcpy().
-// 4. adding read_end_info() and creating an end_info structure.
-
-#include <stddef.h>
-#include <stdint.h>
-#include <string.h>
-
-#include <vector>
-
-#define PNG_INTERNAL
-#include "png.h"
-
-#define PNG_CLEANUP \
-  if(png_handler.png_ptr) \
-  { \
-    if (png_handler.row_ptr) \
-      png_free(png_handler.png_ptr, png_handler.row_ptr); \
-    if (png_handler.end_info_ptr) \
-      png_destroy_read_struct(&png_handler.png_ptr, &png_handler.info_ptr,\
-        &png_handler.end_info_ptr); \
-    else if (png_handler.info_ptr) \
-      png_destroy_read_struct(&png_handler.png_ptr, &png_handler.info_ptr,\
-        nullptr); \
-    else \
-      png_destroy_read_struct(&png_handler.png_ptr, nullptr, nullptr); \
-    png_handler.png_ptr = nullptr; \
-    png_handler.row_ptr = nullptr; \
-    png_handler.info_ptr = nullptr; \
-    png_handler.end_info_ptr = nullptr; \
-  }
-
-struct BufState {
-  const uint8_t* data;
-  size_t bytes_left;
-};
-
-struct PngObjectHandler {
-  png_infop info_ptr = nullptr;
-  png_structp png_ptr = nullptr;
-  png_infop end_info_ptr = nullptr;
-  png_voidp row_ptr = nullptr;
-  BufState* buf_state = nullptr;
-
-  ~PngObjectHandler() {
-    if (row_ptr)
-      png_free(png_ptr, row_ptr);
-    if (end_info_ptr)
-      png_destroy_read_struct(&png_ptr, &info_ptr, &end_info_ptr);
-    else if (info_ptr) 
-      png_destroy_read_struct(&png_ptr, &info_ptr, nullptr);
-    else
-      png_destroy_read_struct(&png_ptr, nullptr, nullptr);
-    delete buf_state;
-  }
-};
-
-void user_read_data(png_structp png_ptr, png_bytep data, png_size_t length) {
-  BufState* buf_state = static_cast<BufState*>(png_get_io_ptr(png_ptr));
-  if (length > buf_state->bytes_left) {
-    png_error(png_ptr, "read error");
-  }
-  memcpy(data, buf_state->data, length);
-  buf_state->bytes_left -= length;
-  buf_state->data += length;
-}
-
-static const int kPngHeaderSize = 8;
-
-// Entry point for LibFuzzer.
-// Roughly follows the libpng book example:
-// http://www.libpng.org/pub/png/book/chapter13.html
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
-  if (size < kPngHeaderSize) {
-    return 0;
-  }
-
-  std::vector<unsigned char> v(data, data + size);
-  if (png_sig_cmp(v.data(), 0, kPngHeaderSize)) {
-    // not a PNG.
-    return 0;
-  }
-
-  PngObjectHandler png_handler;
-  png_handler.png_ptr = nullptr;
-  png_handler.row_ptr = nullptr;
-  png_handler.info_ptr = nullptr;
-  png_handler.end_info_ptr = nullptr;
-
-  png_handler.png_ptr = png_create_read_struct
-    (PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr);
-  if (!png_handler.png_ptr) {
-    return 0;
-  }
-
-  png_handler.info_ptr = png_create_info_struct(png_handler.png_ptr);
-  if (!png_handler.info_ptr) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  png_handler.end_info_ptr = png_create_info_struct(png_handler.png_ptr);
-  if (!png_handler.end_info_ptr) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  png_set_crc_action(png_handler.png_ptr, PNG_CRC_QUIET_USE, PNG_CRC_QUIET_USE);
-#ifdef PNG_IGNORE_ADLER32
-  png_set_option(png_handler.png_ptr, PNG_IGNORE_ADLER32, PNG_OPTION_ON);
-#endif
-
-  // Setting up reading from buffer.
-  png_handler.buf_state = new BufState();
-  png_handler.buf_state->data = data + kPngHeaderSize;
-  png_handler.buf_state->bytes_left = size - kPngHeaderSize;
-  png_set_read_fn(png_handler.png_ptr, png_handler.buf_state, user_read_data);
-  png_set_sig_bytes(png_handler.png_ptr, kPngHeaderSize);
-
-  if (setjmp(png_jmpbuf(png_handler.png_ptr))) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  // Reading.
-  png_read_info(png_handler.png_ptr, png_handler.info_ptr);
-  png_handler.row_ptr = png_malloc(
-      png_handler.png_ptr, png_get_rowbytes(png_handler.png_ptr,
-                                               png_handler.info_ptr));
-
-  // reset error handler to put png_deleter into scope.
-  if (setjmp(png_jmpbuf(png_handler.png_ptr))) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  png_uint_32 width, height;
-  int bit_depth, color_type, interlace_type, compression_type;
-  int filter_type;
-
-  if (!png_get_IHDR(png_handler.png_ptr, png_handler.info_ptr, &width,
-                    &height, &bit_depth, &color_type, &interlace_type,
-                    &compression_type, &filter_type)) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  // This is going to be too slow.
-  if (width && height > 100000000 / width) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  int passes = png_set_interlace_handling(png_handler.png_ptr);
-  png_start_read_image(png_handler.png_ptr);
-
-  for (int pass = 0; pass < passes; ++pass) {
-    for (png_uint_32 y = 0; y < height; ++y) {
-      png_read_row(png_handler.png_ptr,
-                   static_cast<png_bytep>(png_handler.row_ptr), nullptr);
-    }
-  }
-
-  png_read_end(png_handler.png_ptr, png_handler.end_info_ptr);
-
-  PNG_CLEANUP
-  return 0;
-}
--- a/contrib/oss-fuzz/libpng_read_fuzzer.options
+++ b/contrib/oss-fuzz/libpng_read_fuzzer.options
@@ -1,2 +0,0 @@
-[libfuzzer]
-dict = png.dict
--- a/contrib/oss-fuzz/newcc
+++ b/contrib/oss-fuzz/newcc
@@ -1,190 +0,0 @@
-
-// libpng_read_fuzzer.cc
-// Copyright 2017 Glenn Randers-Pehrson
-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that may
-// be found in the LICENSE file https://cs.chromium.org/chromium/src/LICENSE
-
-// Last changed in libpng 1.6.33beta03 [September 27, 2017]
-
-// The modifications in 2017 by Glenn Randers-Pehrson include
-// 1. addition of a PNG_CLEANUP macro,
-// 2. setting the option to ignore ADLER32 checksums,
-// 3. adding "#include <string.h>" which is needed on some platforms
-//    to provide memcpy().
-// 4. adding read_end_info() and creating an end_info structure.
-
-#include <stddef.h>
-#include <stdint.h>
-#include <string.h>
-
-#include <vector>
-
-#define PNG_INTERNAL
-#include "png.h"
-
-struct BufState {
-  const uint8_t* data;
-  size_t bytes_left;
-};
-
-struct PngObjectHandler {
-  png_infop info_ptr = nullptr;
-  png_structp png_ptr = nullptr;
-  png_infop end_info_ptr = nullptr;
-  png_voidp row_ptr = nullptr;
-  BufState* buf_state = nullptr;
-
-  ~PngObjectHandler() {
-    if (row_ptr)
-      png_free(png_ptr, row_ptr);
-    if (end_info_ptr)
-      png_destroy_read_struct(&png_ptr, &info_ptr, &end_info_ptr);
-    else if (info_ptr) 
-      png_destroy_read_struct(&png_ptr, &info_ptr, nullptr);
-    else
-      png_destroy_read_struct(&png_ptr, nullptr, nullptr);
-    delete buf_state;
-  }
-};
-
-void user_read_data(png_structp png_ptr, png_bytep data, png_size_t length) {
-  BufState* buf_state = static_cast<BufState*>(png_get_io_ptr(png_ptr));
-  if (length > buf_state->bytes_left) {
-    png_error(png_ptr, "read error");
-  }
-  memcpy(data, buf_state->data, length);
-  buf_state->bytes_left -= length;
-  buf_state->data += length;
-}
-
-static const int kPngHeaderSize = 8;
-
-// Entry point for LibFuzzer.
-// Roughly follows the libpng book example:
-// http://www.libpng.org/pub/png/book/chapter13.html
-
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
-  if (size < kPngHeaderSize) {
-    return 0;
-  }
-
-  std::vector<unsigned char> v(data, data + size);
-  if (png_sig_cmp(v.data(), 0, kPngHeaderSize)) {
-    // not a PNG.
-    return 0;
-  }
-
-  PngObjectHandler png_handler;
-  png_handler.png_ptr = nullptr;
-  png_handler.row_ptr = nullptr;
-  png_handler.info_ptr = nullptr;
-  png_handler.end_info_ptr = nullptr;
-
-  png_handler.png_ptr = png_create_read_struct
-    (PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr);
-  if (!png_handler.png_ptr) {
-    return 0;
-  }
-
-#define PNG_CLEANUP \
-  if(png_handler.png_ptr) \
-  { \
-    if (png_handler.row_ptr) \
-      png_free(png_handler.png_ptr, png_handler.row_ptr); \
-    if (png_handler.end_info_ptr) \
-      png_destroy_read_struct(&png_handler.png_ptr, &png_handler.info_ptr,\
-        &png_handler.end_info_ptr); \
-    else if (png_handler.info_ptr) \
-      png_destroy_read_struct(&png_handler.png_ptr, &png_handler.info_ptr,\
-        nullptr); \
-    else \
-      png_destroy_read_struct(&png_handler.png_ptr, nullptr, nullptr); \
-    png_handler.png_ptr = nullptr; \
-    png_handler.row_ptr = nullptr; \
-    png_handler.info_ptr = nullptr; \
-    png_handler.end_info_ptr = nullptr; \
-  }
-
-  png_handler.info_ptr = png_create_info_struct(png_handler.png_ptr);
-  if (!png_handler.info_ptr) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  png_handler.end_info_ptr = png_create_info_struct(png_handler.png_ptr);
-  if (!png_handler.end_info_ptr) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  /* Treat benign errors as warnings */
-  png_set_benign_errors(png_handler.png_ptr, 1);
-
-  png_set_crc_action(png_handler.png_ptr, PNG_CRC_QUIET_USE, PNG_CRC_QUIET_USE);
-
-#ifdef PNG_IGNORE_ADLER32
-  png_set_option(png_handler.png_ptr, PNG_IGNORE_ADLER32, PNG_OPTION_ON);
-#endif
-
-  // Setting up reading from buffer.
-  png_handler.buf_state = new BufState();
-  png_handler.buf_state->data = data + kPngHeaderSize;
-  png_handler.buf_state->bytes_left = size - kPngHeaderSize;
-  png_set_read_fn(png_handler.png_ptr, png_handler.buf_state, user_read_data);
-  png_set_sig_bytes(png_handler.png_ptr, kPngHeaderSize);
-
-  if (setjmp(png_jmpbuf(png_handler.png_ptr))) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  // Reading.
-  png_read_info(png_handler.png_ptr, png_handler.info_ptr);
-  png_read_update_info(png_handler.png_ptr, png_handler.info_ptr);
-  png_handler.row_ptr = png_malloc(
-      png_handler.png_ptr, png_get_rowbytes(png_handler.png_ptr,
-                                               png_handler.info_ptr));
-
-  // reset error handler to put png_deleter into scope.
-  if (setjmp(png_jmpbuf(png_handler.png_ptr))) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  png_uint_32 width, height;
-  int bit_depth, color_type, interlace_type, compression_type;
-  int filter_type;
-
-  if (!png_get_IHDR(png_handler.png_ptr, png_handler.info_ptr, &width,
-                    &height, &bit_depth, &color_type, &interlace_type,
-                    &compression_type, &filter_type)) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  // This is going to be too slow.
-  if (width && height > 100000000 / width) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  int passes = png_set_interlace_handling(png_handler.png_ptr);
-  png_start_read_image(png_handler.png_ptr);
-
-  /* To do: prevent the optimizer from removing this code entirely */
-  for (int pass = 0; pass < passes; ++pass) {
-    for (png_uint_32 y = 0; y < height; ++y) {
-      png_read_row(png_handler.png_ptr,
-                   static_cast<png_bytep>(png_handler.row_ptr), nullptr);
-    }
-  }
-
-  png_read_end(png_handler.png_ptr, png_handler.end_info_ptr);
-
-  PNG_CLEANUP
-
-  /* TO do: exercise the progressive reader here */
-
-  return 0;
-}
--- a/contrib/oss-fuzz/png.dict
+++ b/contrib/oss-fuzz/png.dict
@@ -1,39 +0,0 @@
-#
-# AFL dictionary for PNG images
-# -----------------------------
-#
-# Just the basic, standard-originating sections; does not include vendor
-# extensions.
-#
-# Created by Michal Zalewski <lcamtuf@google.com>
-#
-
-header_png="\x89PNG\x0d\x0a\x1a\x0a"
-
-section_IDAT="IDAT"
-section_IEND="IEND"
-section_IHDR="IHDR"
-section_PLTE="PLTE"
-section_bKGD="bKGD"
-section_cHRM="cHRM"
-section_eXIf="eXIf"
-section_fRAc="fRAc"
-section_gAMA="gAMA"
-section_gIFg="gIFg"
-section_gIFt="gIFt"
-section_gIFx="gIFx"
-section_hIST="hIST"
-section_iCCP="iCCP"
-section_iTXt="iTXt"
-section_oFFs="oFFs"
-section_pCAL="pCAL"
-section_pHYs="pHYs"
-section_sBIT="sBIT"
-section_sCAL="sCAL"
-section_sPLT="sPLT"
-section_sRGB="sRGB"
-section_sTER="sTER"
-section_tEXt="tEXt"
-section_tIME="tIME"
-section_tRNS="tRNS"
-section_zTXt="zTXt"
--- a/contrib/pngminus/README
+++ b/contrib/pngminus/README
@@ -146,7 +146,7 @@ The Turbo bug
 The end
 -------
 Willem van Schaik
-mailto:willem at schaik.com
+mailto:willem@schaik.com
 http://www.schaik.com/png/
 -------
 Oct 1999
--- a/contrib/pngminus/png2pnm.c
+++ b/contrib/pngminus/png2pnm.c
@@ -1,12 +1,8 @@
 /*
 *  png2pnm.c --- conversion from PNG-file to PGM/PPM-file
- *  copyright (C) 1999,2017 by Willem van Schaik <willem at schaik.com>
+ *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
 *
 *  version 1.0 - 1999.10.15 - First version.
- *          1.1 - 2017.04.22 - Add buffer-size check (Glenn Randers-Pehrson)
- *          1.2 - 2017.08.24 - Fix potential overflow in buffer-size check
- *                             (Glenn Randers-Pehrson)
- *          1.3 - 2017.08.28 - Add PNGMINUS_UNUSED (Christian Hesse)
 *
 *  Permission to use, copy, modify, and distribute this software and
 *  its documentation for any purpose and without fee is hereby granted,
@@ -45,7 +41,6 @@
 #define PNG_DEBUG 0
 #endif

-
 #include "png.h"

 /* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
@@ -53,14 +48,6 @@
 #  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
 #endif

-#ifndef PNGMINUS_UNUSED
-/* Unused formal parameter warnings are silenced using the following macro
- * which is expected to have no bad effects on performance (optimizing
- * compilers will probably remove it entirely).
- */
-#  define PNGMINUS_UNUSED(param) (void)param
-#endif
-
 /* function prototypes */

 int  main (int argc, char *argv[]);
@@ -279,7 +266,7 @@ BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file,
    png_set_expand (png_ptr);

 #ifdef NJET
-  /* downgrade 16-bit images to 8-bit */
+  /* downgrade 16-bit images to 8 bit */
  if (bit_depth == 16)
    png_set_strip_16 (png_ptr);
  /* transform grayscale images into full-color */
@@ -333,21 +320,14 @@ BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file,
  /* row_bytes is the width x number of channels x (bit-depth / 8) */
  row_bytes = png_get_rowbytes (png_ptr, info_ptr);

-  if ((row_bytes == 0 || (size_t)height > ((size_t)(-1))/(size_t)row_bytes))
-  {
-    /* too big */ 
-    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
-    return FALSE;
-  }
  if ((png_pixels = (png_byte *)
-     malloc ((size_t)row_bytes * (size_t)height * sizeof (png_byte))) == NULL)
-  {
+     malloc (row_bytes * height * sizeof (png_byte))) == NULL) {
    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
    return FALSE;
  }

  if ((row_pointers = (png_byte **)
-     malloc ((size_t)height * sizeof (png_bytep))) == NULL)
+     malloc (height * sizeof (png_bytep))) == NULL)
  {
    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
    free (png_pixels);
@@ -428,8 +408,7 @@ BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file,
          if (raw)
            fputc ((int) *pix_ptr++ , alpha_file);
          else
-            if (bit_depth == 16)
-            {
+            if (bit_depth == 16){
              dep_16 = (long) *pix_ptr++;
              fprintf (alpha_file, "%ld ", (dep_16 << 8) + (long) *pix_ptr++);
            }
@@ -453,7 +432,6 @@ BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file,
  if (png_pixels != (unsigned char*) NULL)
    free (png_pixels);

-  PNGMINUS_UNUSED(raw); /* to quiet a Coverity defect */
  return TRUE;

 } /* end of source */
--- a/contrib/pngminus/pnm2png.c
+++ b/contrib/pngminus/pnm2png.c
@@ -1,13 +1,8 @@
 /*
 *  pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
- *  copyright (C) 1999,2015,2017 by Willem van Schaik <willem at schaik.com>
+ *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
 *
 *  version 1.0 - 1999.10.15 - First version.
- *  version 1.1 - 2015.07.29 - Fixed leaks (Glenn Randers-Pehrson)
- *  version 1.2 - 2017.04.22 - Add buffer-size check
- *          1.3 - 2017.08.24 - Fix potential overflow in buffer-size check
- *                             (Glenn Randers-Pehrson)
- *          1.4 - 2017.08.28 - Add PNGMINUS_UNUSED (Christian Hesse)
 *
 *  Permission to use, copy, modify, and distribute this software and
 *  its documentation for any purpose and without fee is hereby granted,
@@ -51,15 +46,6 @@
 #  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
 #endif

-#ifndef PNGMINUS_UNUSED
-/* Unused formal parameter warnings are silenced using the following macro
- * which is expected to have no bad effects on performance (optimizing
- * compilers will probably remove it entirely).
- */
-#  define PNGMINUS_UNUSED(param) (void)param
-#endif
-
-
 /* function prototypes */

 int  main (int argc, char *argv[]);
@@ -214,17 +200,17 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
  char          width_token[16];
  char          height_token[16];
  char          maxval_token[16];
-  volatile int    color_type=1;
+  volatile int           color_type;
  unsigned long   ul_width=0, ul_alpha_width=0;
  unsigned long   ul_height=0, ul_alpha_height=0;
  unsigned long   ul_maxval=0;
-  volatile png_uint_32   width=0, height=0;
-  volatile png_uint_32   alpha_width=0, alpha_height=0;
+  volatile png_uint_32   width, height;
+  volatile png_uint_32   alpha_width, alpha_height;
  png_uint_32   maxval;
  volatile int           bit_depth = 0;
-  int           channels=0;
+  int           channels;
  int           alpha_depth = 0;
-  int           alpha_present=0;
+  int           alpha_present;
  int           row, col;
  BOOL          raw, alpha_raw = FALSE;
 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
@@ -370,10 +356,8 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
    channels = 3;
  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
    channels = 4;
-#if 0
  else
-    channels = 0; /* cannot happen */
-#endif
+    channels = 0; /* should not happen */

  alpha_present = (channels - 1) % 2;

@@ -383,16 +367,11 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
    row_bytes = (width * channels * bit_depth + 7) / 8;
  else
 #endif
-  /* row_bytes is the width x number of channels x (bit-depth / 8) */
+    /* row_bytes is the width x number of channels x (bit-depth / 8) */
    row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);

-  if ((row_bytes == 0 || (size_t)height > ((size_t)(-1))/(size_t)row_bytes))
-  {
-    /* too big */ 
-    return FALSE;
-  }
  if ((png_pixels = (png_byte *)
-     malloc ((size_t)row_bytes * (size_t)height * sizeof (png_byte))) == NULL)
+     malloc (row_bytes * height * sizeof (png_byte))) == NULL)
    return FALSE;

  /* read data from PNM file */
@@ -401,8 +380,7 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
  for (row = 0; row < (int) height; row++)
  {
 #if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
-    if (packed_bitmap)
-    {
+    if (packed_bitmap) {
      for (i = 0; i < (int) row_bytes; i++)
        /* png supports this format natively so no conversion is needed */
        *pix_ptr++ = get_data (pnm_file, 8);
@@ -451,16 +429,12 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
      NULL);
  if (!png_ptr)
  {
-    free (png_pixels);
-    png_pixels = NULL;
    return FALSE;
  }
  info_ptr = png_create_info_struct (png_ptr);
  if (!info_ptr)
  {
    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
-    free (png_pixels);
-    png_pixels = NULL;
    return FALSE;
  }

@@ -475,9 +449,7 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
  /* setjmp() must be called in every function that calls a PNG-reading libpng function */
  if (setjmp (png_jmpbuf(png_ptr)))
  {
-    png_destroy_write_struct (&png_ptr, &info_ptr);
-    free (png_pixels);
-    png_pixels = NULL;
+    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
    return FALSE;
  }

@@ -498,9 +470,7 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
    if ((row_pointers = (png_byte **)
        malloc (height * sizeof (png_bytep))) == NULL)
    {
-      png_destroy_write_struct (&png_ptr, &info_ptr);
-      free (png_pixels);
-      png_pixels = NULL;
+      png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
      return FALSE;
    }
  }
@@ -516,15 +486,13 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
  png_write_end (png_ptr, info_ptr);

  /* clean up after the write, and free any memory allocated */
-  png_destroy_write_struct (&png_ptr, &info_ptr);
+  png_destroy_write_struct (&png_ptr, (png_infopp) NULL);

  if (row_pointers != (unsigned char**) NULL)
    free (row_pointers);
  if (png_pixels != (unsigned char*) NULL)
    free (png_pixels);

-  PNGMINUS_UNUSED(raw); /* Quiet a Coverity defect */
-
  return TRUE;
 } /* end of pnm2png */

@@ -541,8 +509,7 @@ void get_token(FILE *pnm_file, char *token)
  do
  {
    ret = fgetc(pnm_file);
-    if (ret == '#')
-    {
+    if (ret == '#') {
      /* the rest of this line is a comment */
      do
      {
--- a/contrib/pngsuite/README
+++ b/contrib/pngsuite/README
@@ -1,8 +1,8 @@

 pngsuite
 --------
-Copyright (c) Willem van Schaik, 1999, 2011, 2012
-Two images (ftbbn0g01.png and ftbbn0g02.png) are by Glenn Randers-Pehrson, 2012
+(c) Willem van Schaik, 1999, 2011, 2012
+Two images are by Glenn Randers-Pehrson, 2012

 Permission to use, copy, modify, and distribute these images for any
 purpose and without fee is hereby granted.
@@ -101,5 +101,5 @@ Testing basn6a16.png: PASS (1072 zero samples)
 libpng passes test

 Willem van Schaik
-<willem at schaik.com>
+<willem@schaik.com>
 October 1999
--- a/contrib/powerpc-vsx/README
+++ b/contrib/powerpc-vsx/README
@@ -1,81 +0,0 @@
-OPERATING SYSTEM SPECIFIC POWERPC DETECTION
--------------------------------------------
-
-Detection of the ability to execute POWERPC on processor requires
-operating system support.  (The information is not available in user mode.)
-
-Currently only this feature is supported only for linux platform.
-
-HOW TO USE THIS
---------------
-
-This directory contains C code fragments that can be included in powerpc/powerpc_init.c
-by setting the macro PNG_POWERPC_VSX_FILE to the file name in "" or <> at build
-time.  This setting is not recorded in pnglibconf.h and can be changed simply by
-rebuilding arm/arm_init.o with the required macro definition.
-
-For any of this code to be used the POWERPC code must be enabled and run time
-checks must be supported.  I.e.:
-
-#if PNG_POWERPC_VSX_OPT > 0
-#ifdef PNG_POWERPC_VSX_CHECK_SUPPORTED
-
-This is done in a 'configure' build by passing configure the argument:
-
-   --enable-powerpc-vsx=check
-
-FILE FORMAT
-----------
-
-Each file documents its testing status as of the last time it was tested (which
-may have been a long time ago):
-
-STATUS: one of:
-   SUPPORTED: This indicates that the file is included in the regularly
-         performed test builds and bugs are fixed when discovered.
-   COMPILED: This indicates that the code did compile at least once.  See the
-         more detailed description for the extent to which the result was
-         successful.
-   TESTED: This means the code was fully compiled into the libpng test programs
-         and these were run at least once.
-
-BUG REPORTS: an email address to which to send reports of problems
-
-The file is a fragment of C code. It should not define any 'extern' symbols;
-everything should be static.  It must define the function:
-
-static int png_have_vsx(png_structp png_ptr);
-
-That function must return 1 if ARM NEON instructions are supported, 0 if not.
-It must not execute png_error unless it detects a bug.  A png_error will prevent
-the reading of the PNG and in the future, writing too.
-
-BUG REPORTS
-----------
-
-If you mail a bug report for any file that is not SUPPORTED there may only be
-limited response.  Consider fixing it and sending a patch to fix the problem -
-this is more likely to result in action.
-
-CONTRIBUTIONS
-------------
-
-You may send contributions of new implementations to
-png-mng-implement@sourceforge.net.  Please write code in strict C90 C where
-possible.  Obviously OS dependencies are to be expected.  If you submit code you
-must have the authors permission and it must have a license that is acceptable
-to the current maintainer; in particular that license must permit modification
-and redistribution.
-
-Please try to make the contribution a single file and give the file a clear and
-unambiguous name that identifies the target OS.  If multiple files really are
-required put them all in a sub-directory.
-
-You must also be prepared to handle bug reports from users of the code, either
-by joining the png-mng-implement mailing list or by providing an email for the
-"BUG REPORTS" entry or both.  Please make sure that the header of the file
-contains the STATUS and BUG REPORTS fields as above.
-
-Please list the OS requirements as precisely as possible.  Ideally you should
-also list the environment in which the code has been tested and certainly list
-any environments where you suspect it might not work.
--- a/contrib/powerpc-vsx/linux.c
+++ b/contrib/powerpc-vsx/linux.c
@@ -1,57 +0,0 @@
-/* contrib/powerpc-vsx/linux.c
- *
- * Copyright (c) 2017 Glenn Randers-Pehrson
- * Written by Vadim Barkov, 2017.
- * Last changed in libpng 1.6.29 [March 16, 2017]
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * STATUS: TESTED
- * BUG REPORTS: png-mng-implement@sourceforge.net
- *
- * png_have_vsx implemented for Linux by reading the widely available
- * pseudo-file /proc/cpuinfo. 
- *
- * This code is strict ANSI-C and is probably moderately portable; it does
- * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
- */
-
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include "png.h"
-
-#ifndef MAXLINE
-#  define MAXLINE 1024
-#endif
-
-static int
-png_have_vsx(png_structp png_ptr)
-{
-   FILE *f;
-
-   const char *string = "altivec supported";
-   char input[MAXLINE];
-   char *token = NULL;
-
-   PNG_UNUSED(png_ptr)
-
-   f = fopen("/proc/cpuinfo", "r");
-   if (f != NULL)
-   {
-      memset(input,0,MAXLINE);
-      while(fgets(input,MAXLINE,f) != NULL)
-      {
-         token = strstr(input,string);
-         if(token != NULL)
-            return 1;
-      }
-   }
-#ifdef PNG_WARNINGS_SUPPORTED
-   else
-      png_warning(png_ptr, "/proc/cpuinfo open failed");
-#endif
-   return 0;
-}
--- a/contrib/powerpc-vsx/linux_aux.c
+++ b/contrib/powerpc-vsx/linux_aux.c
@@ -1,36 +0,0 @@
-/* contrib/powerpc-vsx/linux_aux.c
- *
- * Copyright (c) 2017 Glenn Randers-Pehrson
- * Written by Vadim Barkov, 2017.
- * Last changed in libpng 1.6.29 [March 16, 2017]
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * STATUS: TESTED
- * BUG REPORTS: png-mng-implement@sourceforge.net
- *
- * png_have_vsx implemented for Linux by using the auxiliary vector mechanism.
- *
- * This code is strict ANSI-C and is probably moderately portable; it does
- * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
- */
-
-#include "sys/auxv.h"
-#include "png.h"
-
-static int
-png_have_vsx(png_structp png_ptr)
-{
-
-   const unsigned long auxv = getauxval( AT_HWCAP );
-
-   PNG_UNUSED(png_ptr)
-
-   if(auxv & (PPC_FEATURE_HAS_ALTIVEC|PPC_FEATURE_HAS_VSX ))
-      return 1;
-   else
-      return 0;
-}
-
--- a/contrib/testpngs/crashers/bad_iCCP.png
+++ b/contrib/testpngs/crashers/bad_iCCP.png
--- a/contrib/testpngs/crashers/badadler.png
+++ b/contrib/testpngs/crashers/badadler.png
--- a/contrib/testpngs/crashers/badcrc.png
+++ b/contrib/testpngs/crashers/badcrc.png
--- a/contrib/testpngs/crashers/empty_ancillary_chunks.png
+++ b/contrib/testpngs/crashers/empty_ancillary_chunks.png
--- a/contrib/testpngs/crashers/huge_IDAT.png
+++ b/contrib/testpngs/crashers/huge_IDAT.png
--- a/contrib/testpngs/crashers/huge_bKGD_chunk.png
+++ b/contrib/testpngs/crashers/huge_bKGD_chunk.png
--- a/contrib/testpngs/crashers/huge_cHRM_chunk.png
+++ b/contrib/testpngs/crashers/huge_cHRM_chunk.png
--- a/contrib/testpngs/crashers/huge_eXIf_chunk.png
+++ b/contrib/testpngs/crashers/huge_eXIf_chunk.png
--- a/contrib/testpngs/crashers/huge_gAMA_chunk.png
+++ b/contrib/testpngs/crashers/huge_gAMA_chunk.png
--- a/contrib/testpngs/crashers/huge_hIST_chunk.png
+++ b/contrib/testpngs/crashers/huge_hIST_chunk.png
--- a/contrib/testpngs/crashers/huge_iCCP_chunk.png
+++ b/contrib/testpngs/crashers/huge_iCCP_chunk.png
--- a/contrib/testpngs/crashers/huge_iTXt_chunk.png
+++ b/contrib/testpngs/crashers/huge_iTXt_chunk.png
--- a/contrib/testpngs/crashers/huge_juNK_unsafe_to_copy.png
+++ b/contrib/testpngs/crashers/huge_juNK_unsafe_to_copy.png
--- a/contrib/testpngs/crashers/huge_juNk_safe_to_copy.png
+++ b/contrib/testpngs/crashers/huge_juNk_safe_to_copy.png
--- a/contrib/testpngs/crashers/huge_pCAL_chunk.png
+++ b/contrib/testpngs/crashers/huge_pCAL_chunk.png
--- a/contrib/testpngs/crashers/huge_pHYs_chunk.png
+++ b/contrib/testpngs/crashers/huge_pHYs_chunk.png
--- a/contrib/testpngs/crashers/huge_sCAL_chunk.png
+++ b/contrib/testpngs/crashers/huge_sCAL_chunk.png
--- a/contrib/testpngs/crashers/huge_sPLT_chunk.png
+++ b/contrib/testpngs/crashers/huge_sPLT_chunk.png
--- a/contrib/testpngs/crashers/huge_sRGB_chunk.png
+++ b/contrib/testpngs/crashers/huge_sRGB_chunk.png
--- a/contrib/testpngs/crashers/huge_sTER_chunk.png
+++ b/contrib/testpngs/crashers/huge_sTER_chunk.png
--- a/contrib/testpngs/crashers/huge_tEXt_chunk.png
+++ b/contrib/testpngs/crashers/huge_tEXt_chunk.png
--- a/contrib/testpngs/crashers/huge_tIME_chunk.png
+++ b/contrib/testpngs/crashers/huge_tIME_chunk.png
--- a/contrib/testpngs/crashers/huge_zTXt_chunk.png
+++ b/contrib/testpngs/crashers/huge_zTXt_chunk.png
--- a/contrib/testpngs/gray-1-1.8-tRNS.png
+++ b/contrib/testpngs/gray-1-1.8-tRNS.png
--- a/contrib/testpngs/gray-1-1.8.png
+++ b/contrib/testpngs/gray-1-1.8.png
--- a/contrib/testpngs/gray-1-linear-tRNS.png
+++ b/contrib/testpngs/gray-1-linear-tRNS.png
--- a/contrib/testpngs/gray-1-linear.png
+++ b/contrib/testpngs/gray-1-linear.png
--- a/contrib/testpngs/gray-1-sRGB-tRNS.png
+++ b/contrib/testpngs/gray-1-sRGB-tRNS.png
--- a/contrib/testpngs/gray-1-sRGB.png
+++ b/contrib/testpngs/gray-1-sRGB.png
--- a/contrib/testpngs/gray-1-tRNS.png
+++ b/contrib/testpngs/gray-1-tRNS.png
--- a/contrib/testpngs/gray-1.png
+++ b/contrib/testpngs/gray-1.png
--- a/contrib/testpngs/gray-16-1.8-tRNS.png
+++ b/contrib/testpngs/gray-16-1.8-tRNS.png
--- a/contrib/testpngs/gray-16-1.8.png
+++ b/contrib/testpngs/gray-16-1.8.png
--- a/contrib/testpngs/gray-16-linear-tRNS.png
+++ b/contrib/testpngs/gray-16-linear-tRNS.png
--- a/contrib/testpngs/gray-16-linear.png
+++ b/contrib/testpngs/gray-16-linear.png
--- a/contrib/testpngs/gray-16-sRGB-tRNS.png
+++ b/contrib/testpngs/gray-16-sRGB-tRNS.png
--- a/contrib/testpngs/gray-16-sRGB.png
+++ b/contrib/testpngs/gray-16-sRGB.png
--- a/contrib/testpngs/gray-16-tRNS.png
+++ b/contrib/testpngs/gray-16-tRNS.png
--- a/contrib/testpngs/gray-16.png
+++ b/contrib/testpngs/gray-16.png
--- a/contrib/testpngs/gray-2-1.8-tRNS.png
+++ b/contrib/testpngs/gray-2-1.8-tRNS.png
--- a/Show More
+++ b/Show More