[libpng16] Imported from libpng-1.6.33.tar

optimizing out the the core of libpng_read_fuzzer.cc

ANNOUNCE

@@ -1,36 +1,32 @@
-Libpng 1.6.33rc01 - September 20, 2017
+Libpng 1.6.33 - September 28, 2017
 
-This is not intended to be a public release. It will be replaced
-within a few weeks by a public version or by another test version.
+This is a public release of libpng, intended for use in production codes.
 
 Files available for download:
 
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script
 
-   1.6.33rc01.tar.xz (LZMA-compressed, recommended)
-   1.6.33rc01.tar.gz
+   libpng-1.6.33.tar.xz (LZMA-compressed, recommended)
+   libpng-1.6.33.tar.gz
 
 Source files with CRLF line endings (for Windows), without the
 "configure" script
 
-   lp1633r01.7z  (LZMA-compressed, recommended)
-   lp1633r01.zip
+   lpng1633.7z  (LZMA-compressed, recommended)
+   lpng1633.zip
 
 Other information:
 
-   1.6.33rc01-README.txt
-   1.6.33rc01-LICENSE.txt
-   libpng-1.6.33rc01-*.asc (armored detached GPG signatures)
+   libpng-1.6.33-README.txt
+   libpng-1.6.33-LICENSE.txt
+   libpng-1.6.33-*.asc (armored detached GPG signatures)
 
 Changes since the last public release (1.6.32):
-Version 1.6.33beta01 [August 28, 2017]
   Added PNGMINUS_UNUSED macro to contrib/pngminus/p*.c and added missing
     parenthesis in contrib/pngminus/pnm2png.c (bug report by Christian Hesse).
   Fixed off-by-one error in png_do_check_palette_indexes() (Bug report
     by Mick P., Source Forge Issue #269).
-
-Version 1.6.33beta02 [September 3, 2017]
   Initialize png_handler.row_ptr in contrib/oss-fuzz/libpng_read_fuzzer.cc
     to fix shortlived oss-fuzz issue 3234.
   Compute a larger limit on IDAT because some applications write a deflate
@@ -38,22 +34,26 @@ Version 1.6.33beta02 [September 3, 2017]
   Use current date (DATE) instead of release-date (RDATE) in last
     changed date of contrib/oss-fuzz files.
   Enabled ARM support in CMakeLists.txt (Bernd Kuhls).
-
-Version 1.6.33beta03 [September 14, 2017]
   Fixed incorrect typecast of some arguments to png_malloc() and
     png_calloc() that were png_uint_32 instead of png_alloc_size_t
     (Bug report by "irwir" in Github libpng issue #175).
   Use pnglibconf.h.prebuilt when building for ANDROID with cmake (Github
     issue 162, by rcdailey).
-
-Version 1.6.33rc01 [September 20, 2017]
   Initialize memory allocated by png_inflate to zero, using memset, to
     stop an oss-fuzz "use of uninitialized value" detection in png_set_text_2()
-    due to truncated iTXT or zTXT chunk.
+    due to truncated iTXt or zTXt chunk.
   Initialize memory allocated by png_read_buffer to zero, using memset, to
     stop an oss-fuzz "use of uninitialized value" detection in
     png_icc_check_tag_table() due to truncated iCCP chunk.
   Removed a redundant test (suggested by "irwir" in Github issue #180).
+  Added an interlaced version of each file in contrib/pngsuite.
+  Relocate new memset() call in pngrutil.c.
+  Removed more redundant tests (suggested by "irwir" in Github issue #180).
+  Add support for loading images with associated alpha in the Simplified
+    API (Samuel Williams).
+  Revert contrib/oss-fuzz/libpng_read_fuzzer.cc to libpng-1.6.32 state.
+  Initialize png_handler.row_ptr in contrib/oss-fuzz/libpng_read_fuzzer.cc
+  Add end_info structure and png_read_end() to the libpng fuzzer.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit

CHANGES

@@ -833,7 +833,7 @@ Version 1.0.7beta11 [May 7, 2000]
   Removed the new PNG_CREATED_READ_STRUCT and PNG_CREATED_WRITE_STRUCT modes
     which are no longer used.
   Eliminated the three new members of png_text when PNG_LEGACY_SUPPORTED is
-    defined or when neither PNG_READ_iTXt_SUPPORTED nor PNG_WRITE_iTXT_SUPPORTED
+    defined or when neither PNG_READ_iTXt_SUPPORTED nor PNG_WRITE_iTXt_SUPPORTED
     is defined.
   Made PNG_NO_READ|WRITE_iTXt the default setting, to avoid memory
     overrun when old applications fill the info_ptr->text structure directly.
@@ -6019,12 +6019,24 @@ Version 1.6.33beta03 [September 14, 2017]
 Version 1.6.33rc01 [September 20, 2017]
   Initialize memory allocated by png_inflate to zero, using memset, to
     stop an oss-fuzz "use of uninitialized value" detection in png_set_text_2()
-    due to truncated iTXT or zTXT chunk.
+    due to truncated iTXt or zTXt chunk.
   Initialize memory allocated by png_read_buffer to zero, using memset, to
     stop an oss-fuzz "use of uninitialized value" detection in
     png_icc_check_tag_table() due to truncated iCCP chunk.
   Removed a redundant test (suggested by "irwir" in Github issue #180).
 
+Version 1.6.33rc02 [September 23, 2017]
+  Added an interlaced version of each file in contrib/pngsuite.
+  Relocate new memset() call in pngrutil.c.
+  Removed more redundant tests (suggested by "irwir" in Github issue #180).
+  Add support for loading images with associated alpha in the Simplified
+    API (Samuel Williams).
+
+Version 1.6.33 [September 28, 2017]
+  Revert contrib/oss-fuzz/libpng_read_fuzzer.cc to libpng-1.6.32 state.
+  Initialize png_handler.row_ptr in contrib/oss-fuzz/libpng_read_fuzzer.cc
+  Add end_info structure and png_read_end() to the libpng fuzzer.
+
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement

CMakeLists.txt

@@ -844,7 +844,7 @@ endif(NOT WIN32 OR CYGWIN OR MINGW)
 # SET UP LINKS
 if(PNG_SHARED)
   set_target_properties(png PROPERTIES
-#   VERSION 16.${PNGLIB_RELEASE}.1.6.33rc01
+#   VERSION 16.${PNGLIB_RELEASE}.1.6.33
     VERSION 16.${PNGLIB_RELEASE}.0
     SOVERSION 16
     CLEAN_DIRECT_OUTPUT 1)

LICENSE

@@ -10,7 +10,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.0.7, July 1, 2000 through 1.6.33rc01, September 20, 2017 are
+libpng versions 1.0.7, July 1, 2000 through 1.6.33, September 28, 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
@@ -130,4 +130,4 @@ any encryption software.  See the EAR, paragraphs 734.3(b)(3) and
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-September 20, 2017
+September 28, 2017

README

@@ -1,4 +1,4 @@
-README for libpng version 1.6.33rc01 - September 20, 2017 (shared library 16.0)
+README for libpng version 1.6.33 - September 28, 2017 (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.

configure.ac

@@ -25,7 +25,7 @@ AC_PREREQ([2.68])
 
 dnl Version number stuff here:
 
-AC_INIT([libpng],[1.6.33rc01],[png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng],[1.6.33],[png-mng-implement@lists.sourceforge.net])
 AC_CONFIG_MACRO_DIR([scripts])
 
 # libpng does not follow GNU file name conventions (hence 'foreign')
@@ -46,7 +46,7 @@ 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=1.6.33rc01
+PNGLIB_VERSION=1.6.33
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=6
 PNGLIB_RELEASE=33

contrib/oss-fuzz/README.txt

@@ -1,4 +1,4 @@
-Last changed in libpng 1.6.33 [(PENDING RELEASE)]
+Last changed in libpng 1.6.33 [September 28, 2017]
 Copyright (c) 2017 Glenn Randers-Pehrson
 
 This code is released under the libpng license.
@@ -13,7 +13,7 @@ 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-Pehson
+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

contrib/oss-fuzz/build.sh

@@ -14,7 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-# Last changed in libpng 1.6.32 [August 24, 2017]
+# 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
@@ -43,7 +43,7 @@ $CXX $CXXFLAGS -std=c++11 -I. \
      -lFuzzingEngine .libs/libpng16.a -lz
 
 # add seed corpus.
-find $SRC/libpng -name "*.png" | \
+find $SRC/libpng -name "*.png" | grep -v crashers | \
      xargs zip $OUT/libpng_read_fuzzer_seed_corpus.zip
 
 cp $SRC/libpng/contrib/oss-fuzz/*.dict \

contrib/oss-fuzz/libpng_read_fuzzer.cc

@@ -5,7 +5,7 @@
 // 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 20, 2017]
+// 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,
@@ -23,6 +23,25 @@
 #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;
@@ -63,7 +82,6 @@ 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;
@@ -87,25 +105,6 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
     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
@@ -119,7 +118,6 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
   }
 
   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
@@ -138,7 +136,6 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
 
   // 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));
@@ -179,8 +176,5 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
   png_read_end(png_handler.png_ptr, png_handler.end_info_ptr);
 
   PNG_CLEANUP
-
-  /* TO do: exercise the progressive reader here */
-
   return 0;
 }

contrib/oss-fuzz/newcc

@@ -0,0 +1,190 @@
+
+// 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;
+}

contrib/pngsuite/README

@@ -16,6 +16,8 @@ chunks, etc.
 The "ft*.png" images are "free/libre" replacements for the transparent
 corresponding t*.png images in the PngSuite.
 
+The "i*.png" images are the same complete set, but interlaced.
+
 The images in this directory represent the basic PNG color-types:
 grayscale (1-16 bit deep), full color (8 or 16 bit), paletted
 (1-8 bit) and grayscale or color images with alpha channel. You

libpng-manual.txt

@@ -1,6 +1,6 @@
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.6.33rc01 - September 20, 2017
+ libpng version 1.6.33 - September 28, 2017
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2017 Glenn Randers-Pehrson
@@ -11,7 +11,7 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.6.33rc01 - September 20, 2017
+ libpng versions 0.97, January 1998, through 1.6.33 - September 28, 2017
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2017 Glenn Randers-Pehrson
 
@@ -986,8 +986,17 @@ premultiplication.
 
     png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
 
-This is the default libpng handling of the alpha channel - it is not
-pre-multiplied into the color components.  In addition the call states
+Choices for the alpha_mode are
+
+    PNG_ALPHA_PNG           0 /* according to the PNG standard */
+    PNG_ALPHA_STANDARD      1 /* according to Porter/Duff */
+    PNG_ALPHA_ASSOCIATED    1 /* as above; this is the normal practice */
+    PNG_ALPHA_PREMULTIPLIED 1 /* as above */
+    PNG_ALPHA_OPTIMIZED     2 /* 'PNG' for opaque pixels, else 'STANDARD' */
+    PNG_ALPHA_BROKEN        3 /* the alpha channel is gamma encoded */
+
+PNG_ALPHA_PNG is the default libpng handling of the alpha channel. It is not
+pre-multiplied into the color components. In addition the call states
 that the output is for a sRGB system and causes all PNG files without gAMA
 chunks to be assumed to be encoded using sRGB.
 
@@ -1002,7 +1011,7 @@ early Mac systems behaved.
 This is the classic Jim Blinn approach and will work in academic
 environments where everything is done by the book.  It has the shortcoming
 of assuming that input PNG data with no gamma information is linear - this
-is unlikely to be correct unless the PNG files where generated locally.
+is unlikely to be correct unless the PNG files were generated locally.
 Most of the time the output precision will be so low as to show
 significant banding in dark areas of the image.
 
@@ -5405,7 +5414,7 @@ Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
 
 This is your unofficial assurance that libpng from version 0.71 and
-upward through 1.6.33rc01 are Y2K compliant.  It is my belief that earlier
+upward through 1.6.33 are Y2K compliant.  It is my belief that earlier
 versions were also Y2K compliant.
 
 Libpng only has two year fields.  One is a 2-byte unsigned integer

libpng.3

@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "September 20, 2017"
+.TH LIBPNG 3 "September 28, 2017"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.33rc01
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.33
 .SH SYNOPSIS
 \fB
 #include <png.h>\fP
@@ -518,7 +518,7 @@ Following is a copy of the libpng-manual.txt file that accompanies libpng.
 .SH LIBPNG.TXT
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.6.33rc01 - September 20, 2017
+ libpng version 1.6.33 - September 28, 2017
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2017 Glenn Randers-Pehrson
@@ -529,7 +529,7 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.6.33rc01 - September 20, 2017
+ libpng versions 0.97, January 1998, through 1.6.33 - September 28, 2017
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2017 Glenn Randers-Pehrson
 
@@ -1504,8 +1504,17 @@ premultiplication.
 
     png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
 
-This is the default libpng handling of the alpha channel - it is not
-pre-multiplied into the color components.  In addition the call states
+Choices for the alpha_mode are
+
+    PNG_ALPHA_PNG           0 /* according to the PNG standard */
+    PNG_ALPHA_STANDARD      1 /* according to Porter/Duff */
+    PNG_ALPHA_ASSOCIATED    1 /* as above; this is the normal practice */
+    PNG_ALPHA_PREMULTIPLIED 1 /* as above */
+    PNG_ALPHA_OPTIMIZED     2 /* 'PNG' for opaque pixels, else 'STANDARD' */
+    PNG_ALPHA_BROKEN        3 /* the alpha channel is gamma encoded */
+
+PNG_ALPHA_PNG is the default libpng handling of the alpha channel. It is not
+pre-multiplied into the color components. In addition the call states
 that the output is for a sRGB system and causes all PNG files without gAMA
 chunks to be assumed to be encoded using sRGB.
 
@@ -1520,7 +1529,7 @@ early Mac systems behaved.
 This is the classic Jim Blinn approach and will work in academic
 environments where everything is done by the book.  It has the shortcoming
 of assuming that input PNG data with no gamma information is linear - this
-is unlikely to be correct unless the PNG files where generated locally.
+is unlikely to be correct unless the PNG files were generated locally.
 Most of the time the output precision will be so low as to show
 significant banding in dark areas of the image.
 
@@ -5923,7 +5932,7 @@ Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
 
 This is your unofficial assurance that libpng from version 0.71 and
-upward through 1.6.33rc01 are Y2K compliant.  It is my belief that earlier
+upward through 1.6.33 are Y2K compliant.  It is my belief that earlier
 versions were also Y2K compliant.
 
 Libpng only has two year fields.  One is a 2-byte unsigned integer
@@ -6025,7 +6034,7 @@ the first widely used release:
  ...
  1.5.28                  15    10528  15.so.15.28[.0]
  ...
- 1.6.32                  16    10632  16.so.16.32[.0]
+ 1.6.33                  16    10633  16.so.16.33[.0]
 
 Henceforth the source version will match the shared-library minor
 and patch numbers; the shared-library major version number will be
@@ -6081,7 +6090,7 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.6.33rc01 - September 20, 2017:
+Libpng version 1.6.33 - September 28, 2017:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -6106,7 +6115,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.0.7, July 1, 2000 through 1.6.33rc01, September 20, 2017 are
+libpng versions 1.0.7, July 1, 2000 through 1.6.33, September 28, 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
@@ -6234,7 +6243,7 @@ files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-September 20, 2017
+September 28, 2017
 
 .\" end of man page
 

libpngpf.3

@@ -1,6 +1,6 @@
 .TH LIBPNGPF 3 "April 1, 2017"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.33rc01
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.33
 (private functions)
 .SH SYNOPSIS
 \fB\fB#include \fI\fI"pngpriv.h"

png.c

@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * Last changed in libpng 1.6.33 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.33 [September 28, 2017]
  * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -14,7 +14,7 @@
 #include "pngpriv.h"
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_33rc01 Your_png_h_is_not_version_1_6_33rc01;
+typedef png_libpng_version_1_6_33 Your_png_h_is_not_version_1_6_33;
 
 #ifdef __GNUC__
 /* The version tests may need to be added to, but the problem warning has
@@ -816,14 +816,14 @@ png_get_copyright(png_const_structrp png_ptr)
 #else
 #  ifdef __STDC__
    return PNG_STRING_NEWLINE \
-      "libpng version 1.6.33rc01 - September 20, 2017" PNG_STRING_NEWLINE \
+      "libpng version 1.6.33 - September 28, 2017" PNG_STRING_NEWLINE \
       "Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson" \
       PNG_STRING_NEWLINE \
       "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
       "Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
       PNG_STRING_NEWLINE;
 #  else
-   return "libpng version 1.6.33rc01 - September 20, 2017\
+   return "libpng version 1.6.33 - September 28, 2017\
       Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
@@ -3761,7 +3761,7 @@ png_log16bit(png_uint_32 x)
  * of getting this accuracy in practice.
  *
  * To deal with this the following exp() function works out the exponent of the
- * frational part of the logarithm by using an accurate 32-bit value from the
+ * fractional part of the logarithm by using an accurate 32-bit value from the
  * top four fractional bits then multiplying in the remaining bits.
  */
 static const png_uint_32

png.h

@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.6.33rc01, September 20, 2017
+ * libpng version 1.6.33, September 28, 2017
  *
  * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -12,7 +12,7 @@
  * Authors and maintainers:
  *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
  *   libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
- *   libpng versions 0.97, January 1998, through 1.6.33rc01, September 20, 2017:
+ *   libpng versions 0.97, January 1998, through 1.6.33, September 28, 2017:
  *     Glenn Randers-Pehrson.
  *   See also "Contributing Authors", below.
  */
@@ -25,7 +25,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.0.7, July 1, 2000 through 1.6.33rc01, September 20, 2017 are
+ * libpng versions 1.0.7, July 1, 2000 through 1.6.33, September 28, 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
@@ -213,7 +213,7 @@
  *    ...
  *    1.5.28                  15    10527  15.so.15.28[.0]
  *    ...
- *    1.6.32                  16    10632  16.so.16.32[.0]
+ *    1.6.33                  16    10633  16.so.16.33[.0]
  *
  *    Henceforth the source version will match the shared-library major
  *    and minor numbers; the shared-library major version number will be
@@ -241,13 +241,13 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    September 20, 2017
+ *    September 28, 2017
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
  *
  *    This is your unofficial assurance that libpng from version 0.71 and
- *    upward through 1.6.33rc01 are Y2K compliant.  It is my belief that
+ *    upward through 1.6.33 are Y2K compliant.  It is my belief that
  *    earlier versions were also Y2K compliant.
  *
  *    Libpng only has two year fields.  One is a 2-byte unsigned integer
@@ -309,8 +309,8 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.6.33rc01"
-#define PNG_HEADER_VERSION_STRING " libpng version 1.6.33rc01 - September 20, 2017\n"
+#define PNG_LIBPNG_VER_STRING "1.6.33"
+#define PNG_HEADER_VERSION_STRING " libpng version 1.6.33 - September 28, 2017\n"
 
 #define PNG_LIBPNG_VER_SONUM   16
 #define PNG_LIBPNG_VER_DLLNUM  16
@@ -324,7 +324,7 @@
  * PNG_LIBPNG_VER_STRING, omitting any leading zero:
  */
 
-#define PNG_LIBPNG_VER_BUILD  01
+#define PNG_LIBPNG_VER_BUILD  0
 
 /* Release Status */
 #define PNG_LIBPNG_BUILD_ALPHA    1
@@ -341,7 +341,7 @@
 #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
                                        PNG_LIBPNG_BUILD_PRIVATE */
 
-#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_RC
+#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_STABLE
 
 /* Careful here.  At one time, Guy wanted to use 082, but that would be octal.
  * We must not include leading zeros.
@@ -459,7 +459,7 @@ extern "C" {
 /* This triggers a compiler error in png.c, if png.c and png.h
  * do not agree upon the version number.
  */
-typedef char* png_libpng_version_1_6_33rc01;
+typedef char* png_libpng_version_1_6_33;
 
 /* Basic control structions.  Read libpng-manual.txt or libpng.3 for more info.
  *
@@ -2819,6 +2819,8 @@ typedef struct
 #  define PNG_FORMAT_FLAG_AFIRST 0x20U /* alpha channel comes first */
 #endif
 
+#define PNG_FORMAT_FLAG_ASSOCIATED_ALPHA 0x40U /* alpha channel is associated */
+
 /* Commonly used formats have predefined macros.
  *
  * First the single byte (sRGB) formats:

pngconf.h

@@ -1,7 +1,7 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.6.33rc01, September 20, 2017
+ * libpng version 1.6.33, September 28, 2017
  *
  * Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)

pngread.c

@@ -1,7 +1,7 @@
 
 /* pngread.c - read a PNG file
  *
- * Last changed in libpng 1.6.32 [August 24, 2017]
+ * Last changed in libpng 1.6.33 [September 28, 2017]
  * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -3759,7 +3759,13 @@ png_image_read_direct(png_voidp argument)
          mode = PNG_ALPHA_PNG;
          output_gamma = PNG_DEFAULT_sRGB;
       }
-
+      
+      if ((change & PNG_FORMAT_FLAG_ASSOCIATED_ALPHA) != 0)
+      {
+         mode = PNG_ALPHA_OPTIMIZED;
+         change &= ~PNG_FORMAT_FLAG_ASSOCIATED_ALPHA;
+      }
+      
       /* If 'do_local_background' is set check for the presence of gamma
        * correction; this is part of the work-round for the libpng bug
        * described above.
@@ -3985,6 +3991,10 @@ png_image_read_direct(png_voidp argument)
       else if (do_local_compose != 0) /* internal error */
          png_error(png_ptr, "png_image_read: alpha channel lost");
 
+      if ((format & PNG_FORMAT_FLAG_ASSOCIATED_ALPHA) != 0) {
+         info_format |= PNG_FORMAT_FLAG_ASSOCIATED_ALPHA;
+      }
+
       if (info_ptr->bit_depth == 16)
          info_format |= PNG_FORMAT_FLAG_LINEAR;
 

pngrtran.c

@@ -1,7 +1,7 @@
 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * Last changed in libpng 1.6.33 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.33 [September 28, 2017]
  * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)

pngrutil.c

@@ -1,7 +1,7 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * Last changed in libpng 1.6.33 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.33 [September 28, 2017]
  * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -671,10 +671,11 @@ png_decompress_chunk(png_structrp png_ptr,
                    (terminate != 0);
                png_bytep text = png_voidcast(png_bytep, png_malloc_base(png_ptr,
                    buffer_size));
-               memset(text, 0, buffer_size);
 
                if (text != NULL)
                {
+                  memset(text, 0, buffer_size);
+
                   ret = png_inflate(png_ptr, png_ptr->chunk_name, 1/*finish*/,
                       png_ptr->read_buffer + prefix_size, &lzsize,
                       text + prefix_size, newlength);
@@ -1583,19 +1584,11 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
                                        return;
                                     }
                                  }
-
-                                 else if (size > 0)
-                                    errmsg = "truncated";
-
-#ifndef __COVERITY__
-                                 else
+                                 if (errmsg == NULL)
                                     errmsg = png_ptr->zstream.msg;
-#endif
                               }
-
                               /* else png_icc_check_tag_table output an error */
                            }
-
                            else /* profile truncated */
                               errmsg = png_ptr->zstream.msg;
                         }

pngtest.c

@@ -2153,4 +2153,4 @@ main(void)
 #endif
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_33rc01 Your_png_h_is_not_version_1_6_33rc01;
+typedef png_libpng_version_1_6_33 Your_png_h_is_not_version_1_6_33;

pngtrans.c

@@ -1,7 +1,7 @@
 
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
- * Last changed in libpng 1.6.33 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.33 [September 28, 2017]
  * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)

pngwrite.c

@@ -1940,7 +1940,7 @@ png_image_write_main(png_voidp argument)
    int colormap = (format & PNG_FORMAT_FLAG_COLORMAP);
    int linear = !colormap && (format & PNG_FORMAT_FLAG_LINEAR); /* input */
    int alpha = !colormap && (format & PNG_FORMAT_FLAG_ALPHA);
-   int write_16bit = linear && !colormap && (display->convert_to_8bit == 0);
+   int write_16bit = linear && (display->convert_to_8bit == 0);
 
 #   ifdef PNG_BENIGN_ERRORS_SUPPORTED
       /* Make sure we error out on any bad situation */

projects/vstudio/README.txt

@@ -1,7 +1,7 @@
 
 VisualStudio instructions
 
-libpng version 1.6.33rc01 - September 20, 2017
+libpng version 1.6.33 - September 28, 2017
 
 Copyright (c) 2010,2013,2015 Glenn Randers-Pehrson
 

projects/vstudio/zlib.props

@@ -2,7 +2,7 @@
 <!--
  * zlib.props - location of zlib source
  *
- * libpng version 1.6.33rc01 - September 20, 2017
+ * libpng version 1.6.33 - September 28, 2017
  *
  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  *

scripts/README.txt

@@ -1,11 +1,11 @@
 
-Makefiles for  libpng version 1.6.33rc01 - September 20, 2017
+Makefiles for  libpng version 1.6.33 - September 28, 2017
 
 pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.linux    =>  Linux/ELF makefile
-                       (gcc, creates libpng16.so.16.1.6.33rc01)
+                       (gcc, creates libpng16.so.16.1.6.33)
  makefile.linux-opt=>  Linux/ELF makefile with hardware optimizations on
-                       (gcc, creates libpng16.so.16.1.6.33rc01)
+                       (gcc, creates libpng16.so.16.1.6.33)
  makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a)
  makefile.knr      =>  Archaic UNIX Makefile that converts files with
                        ansi2knr (Requires ansi2knr.c from
@@ -35,12 +35,12 @@ pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.os2      =>  OS/2 Makefile (gcc and emx, requires libpng.def)
  makefile.sco      =>  For SCO OSr5  ELF and Unixware 7 with Native cc
  makefile.sggcc    =>  Silicon Graphics (gcc,
-                       creates libpng16.so.16.1.6.33rc01)
+                       creates libpng16.so.16.1.6.33)
  makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
  makefile.solaris  =>  Solaris 2.X makefile (gcc,
-                       creates libpng16.so.16.1.6.33rc01)
+                       creates libpng16.so.16.1.6.33)
  makefile.so9      =>  Solaris 9 makefile (gcc,
-                       creates libpng16.so.16.1.6.33rc01)
+                       creates libpng16.so.16.1.6.33)
  makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a)
  makefile.sunos    =>  Sun makefile
  makefile.32sunu   =>  Sun Ultra 32-bit makefile

scripts/def.c

@@ -21,7 +21,7 @@ PNG_DFN "OS2 DESCRIPTION "PNG image compression library""
 PNG_DFN "OS2 CODE PRELOAD MOVEABLE DISCARDABLE"
 PNG_DFN ""
 PNG_DFN "EXPORTS"
-PNG_DFN ";Version 1.6.33rc01"
+PNG_DFN ";Version 1.6.33"
 
 #define PNG_EXPORTA(ordinal, type, name, args, attributes)\
         PNG_DFN "@" SYMBOL_PREFIX "@@" name "@"

scripts/libpng-config-head.in

@@ -11,7 +11,7 @@
 
 # Modeled after libxml-config.
 
-version=1.6.33rc01
+version=1.6.33
 prefix=""
 libdir=""
 libs=""

scripts/libpng.pc.in

@@ -5,6 +5,6 @@ includedir=@includedir@/libpng16
 
 Name: libpng
 Description: Loads and saves PNG files
-Version: 1.6.33rc01
+Version: 1.6.33
 Libs: -L${libdir} -lpng16
 Cflags: -I${includedir}

scripts/makefile.ne12bsd

@@ -17,7 +17,7 @@ INCSDIR=${LOCALBASE}/include/libpng16
 
 LIB=	png16
 SHLIB_MAJOR=	0
-SHLIB_MINOR=	1.6.33rc01
+SHLIB_MINOR=	1.6.33
 SRCS=	png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
 	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
 	pngwtran.c pngmem.c pngerror.c pngpread.c

scripts/makefile.netbsd

@@ -17,7 +17,7 @@ INCSDIR=${LOCALBASE}/include
 
 LIB=	png
 SHLIB_MAJOR=	16
-SHLIB_MINOR=	1.6.33rc01
+SHLIB_MINOR=	1.6.33
 SRCS=	png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
 	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
 	pngwtran.c pngmem.c pngerror.c pngpread.c

scripts/makefile.openbsd

@@ -11,7 +11,7 @@ LIBDIR=	${PREFIX}/lib
 MANDIR= ${PREFIX}/man/cat
 
 SHLIB_MAJOR=	16
-SHLIB_MINOR=	1.6.33rc01
+SHLIB_MINOR=	1.6.33
 
 LIB=	png
 SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \

scripts/pnglibconf.h.prebuilt

@@ -1,8 +1,8 @@
-/* libpng 1.6.33rc01 STANDARD API DEFINITION */
+/* libpng 1.6.33 STANDARD API DEFINITION */
 
 /* pnglibconf.h - library build configuration */
 
-/* Libpng version 1.6.33rc01 - September 20, 2017 */
+/* Libpng version 1.6.33 - September 28, 2017 */
 
 /* Copyright (c) 1998-2017 Glenn Randers-Pehrson */
 

scripts/symbols.def

@@ -1,4 +1,4 @@
-;Version 1.6.33rc01
+;Version 1.6.33
 ;--------------------------------------------------------------
 ; LIBPNG symbol list as a Win32 DEF file
 ; Contains all the symbols that can be exported from libpng