[libpng17] Imported from libpng-1.7.0beta80.tar

A debug() assert fired if windowBits was set to 8 for the Huffman only and
no-compression cases.  This commit changes it to do some extra checking.  Remove
unreachable code in pz_default_settings, eliminate a spurious warning in pngcp
for small files.

Signed-off-by: John Bowler <jbowler@acm.org>

ANNOUNCE

@@ -1,5 +1,5 @@
 
-Libpng 1.7.0beta79 - March 9, 2016
+Libpng 1.7.0beta80 - May 6, 2016
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -9,20 +9,20 @@ Files available for download:
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script
 
-   1.7.0beta79.tar.xz (LZMA-compressed, recommended)
-   1.7.0beta79.tar.gz
+   1.7.0beta80.tar.xz (LZMA-compressed, recommended)
+   1.7.0beta80.tar.gz
 
 Source files with CRLF line endings (for Windows), without the
 "configure" script
 
-   /scratch/glennrp/Libpng17/lp170b79.7z  (LZMA-compressed, recommended)
-   /scratch/glennrp/Libpng17/lp170b79.zip
+   /scratch/glennrp/Libpng17/lp170b80.7z  (LZMA-compressed, recommended)
+   /scratch/glennrp/Libpng17/lp170b80.zip
 
 Other information:
 
-   1.7.0beta79-README.txt
-   1.7.0beta79-LICENSE.txt
-   libpng-1.7.0beta79-*.asc (armored detached GPG signatures)
+   1.7.0beta80-README.txt
+   1.7.0beta80-LICENSE.txt
+   libpng-1.7.0beta80-*.asc (armored detached GPG signatures)
 
 Changes since the last public release (1.6.0):
 
@@ -1264,6 +1264,32 @@ Version 1.7.0beta79 [March 9, 2016]
     (Robert C. Seacord). Various other flags in png.h made unsigned as well.
   Fixed some misleading indentation (Krishnaraj Bhat).
 
+Version 1.7.0beta80 [May 6, 2016]
+  Fixed typo (missing underscore) in #define PNG_READ_16_TO_8_SUPPORTED
+    Bug report by (Y.Ohashik).
+  Quieted two Coverity issues in contrib/libtests/timepng.c.
+  Write code update (John Bowler):
+    Implemented better defaulting of zlib settings based on image properties.
+    Replaced pngtest.png with one compressed with the new zlib settings.
+    Implemented pass-through of png_write_rows when the rows can be used
+      directly (a common case) optimizing the handling of previous-row
+      buffering.
+    Removed the METHODICAL filter selection method and disabled the HEURISTIC
+      one.  The first was ridiculously slow (though useful for experiments),
+      and the second didn't work. Filter selection is temporarily disabled (it
+      defaults to the lowest numbered filter in the list; typically 'none').
+    New handling of compression settings (incomplete), new PNG compression level
+      (not yet visible in an API).
+    Back ported 'PNG_FAST_FILTERS' from 1.6 (in png.h).
+    There are minimal API changes beyond removal of the selection options.
+      Work is still to be done to investigate a filter selection mechanism that
+      is at least as good as the previous one.
+    Minor write bug-fixes, remove unimplemented code.  A debug() assert
+      fired if windowBits was set to 8 for the Huffman only and no-compression
+      cases. This commit changes it to do some extra checking.  Removed
+      unreachable code in pz_default_settings and eliminated a spurious
+      warning in pngcp for small files.
+
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement

CHANGES

@@ -5564,6 +5564,32 @@ Version 1.7.0beta79 [March 9, 2016]
     (Robert C. Seacord). Various other flags in png.h made unsigned as well.
   Fixed some misleading indentation (Krishnaraj Bhat).
 
+Version 1.7.0beta80 [May 6, 2016]
+  Fixed typo (missing underscore) in #define PNG_READ_16_TO_8_SUPPORTED
+    Bug report by (Y.Ohashik).
+  Quieted two Coverity issues in contrib/libtests/timepng.c.
+  Write code update (John Bowler):
+    Implemented better defaulting of zlib settings based on image properties.
+    Replaced pngtest.png with one compressed with the new zlib settings.
+    Implemented pass-through of png_write_rows when the rows can be used
+      directly (a common case) optimizing the handling of previous-row
+      buffering.
+    Removed the METHODICAL filter selection method and disabled the HEURISTIC
+      one.  The first was ridiculously slow (though useful for experiments),
+      and the second didn't work. Filter selection is temporarily disabled (it
+      defaults to the lowest numbered filter in the list; typically 'none').
+    New handling of compression settings (incomplete), new PNG compression level
+      (not yet visible in an API).
+    Back ported 'PNG_FAST_FILTERS' from 1.6 (in png.h).
+    There are minimal API changes beyond removal of the selection options.
+      Work is still to be done to investigate a filter selection mechanism that
+      is at least as good as the previous one.
+    Minor write bug-fixes, remove unimplemented code.  A debug() assert
+      fired if windowBits was set to 8 for the Huffman only and no-compression
+      cases. This commit changes it to do some extra checking.  Removed
+      unreachable code in pz_default_settings and eliminated a spurious
+      warning in pngcp for small files.
+
 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

@@ -697,7 +697,7 @@ endif(NOT WIN32 OR CYGWIN OR MINGW)
 # SET UP LINKS
 if(PNG_SHARED)
   set_target_properties(png PROPERTIES
-#   VERSION 17.${PNGLIB_RELEASE}.1.7.0beta79
+#   VERSION 17.${PNGLIB_RELEASE}.1.7.0beta80
     VERSION 17.${PNGLIB_RELEASE}.0
     SOVERSION 17
     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 1.7.0beta79, March 9, 2016, are
+libpng versions 1.0.7, July 1, 2000, through 1.7.0beta80, May 6, 2016, are
 Copyright (c) 2000-2002, 2004, 2006-2016 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
@@ -109,4 +109,4 @@ the additional disclaimers inserted at version 1.0.7.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-March 9, 2016
+May 6, 2016

README

@@ -1,4 +1,4 @@
-README for libpng version 1.7.0beta79 - March 9, 2016 (shared library 17.0)
+README for libpng version 1.7.0beta80 - May 6, 2016 (shared library 17.0)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.

configure.ac

@@ -18,7 +18,7 @@ AC_PREREQ([2.68])
 
 dnl Version number stuff here:
 
-AC_INIT([libpng],[1.7.0beta79],[png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng],[1.7.0beta80],[png-mng-implement@lists.sourceforge.net])
 AC_CONFIG_MACRO_DIR([scripts])
 
 # libpng does not follow GNU file name conventions (hence 'foreign')
@@ -40,7 +40,7 @@ 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=1.7.0beta79
+PNGLIB_VERSION=1.7.0beta80
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=7
 PNGLIB_RELEASE=0

contrib/examples/pngcp.c

@@ -328,6 +328,7 @@ struct display
    int              bpp;
    png_byte         ct;
    int              no_warnings;       /* Do not output libpng warnings */
+   int              min_windowBits;    /* The windowBits range is 8..8 */
 
    /* Options handling */
    png_uint_32      results;           /* A mask of errors seen */
@@ -389,6 +390,7 @@ display_init(struct display *dp)
    dp->read_pp = NULL;
    dp->ip = NULL;
    dp->write_pp = NULL;
+   dp->min_windowBits = -1; /* this is an OPTIND, so -1 won't match anything */
 #  if PNG_LIBPNG_VER < 10700
       dp->text_ptr = NULL;
       dp->num_text = 0;
@@ -775,8 +777,12 @@ push_opt(struct display *dp, unsigned int sp, png_byte opt, int search)
    if (opt_list_end(dp, opt, entry))
    {
       dp->stack[sp].end = 1;
-      display_log(dp, APP_WARNING, "%s: only testing one value",
-            options[opt].name);
+      /* Skip the warning if pngcp did this itself.  See the code in
+       * set_windowBits_hi.
+       */
+      if (opt != dp->min_windowBits)
+         display_log(dp, APP_WARNING, "%s: only testing one value",
+               options[opt].name);
    }
 
    else
@@ -1193,8 +1199,8 @@ getsearchopts(struct display *dp, const char *opt_str, int *value)
    else if (opt == OPTIND(dp, windowBits))
    {
       /* Changing windowBits for strategies that do not search the window is
-       * pointless.  Huffman-only does not search, RLE only searchs backwards
-       * one byte, so give that the maximum string length is 258, a windowBits
+       * pointless.  Huffman-only does not search, RLE only searches backwards
+       * one byte, so given that the maximum string length is 258, a windowBits
        * of 9 is always sufficient.
        */
       if (dp->value[istrat] == Z_HUFFMAN_ONLY)
@@ -1609,10 +1615,10 @@ read_png(struct display *dp, const char *filename)
       png_alloc_size_t rb = png_get_rowbytes(dp->read_pp, dp->ip);
 
       /* The size calc can overflow. */
-      if (MAX_SIZE/rb < dp->h)
+      if ((MAX_SIZE-dp->h)/rb < dp->h)
          png_error(dp->read_pp, "image too large");
 
-      dp->size = rb * dp->h;
+      dp->size = rb * dp->h + dp->h/*filter byte*/;
    }
 
    display_clean_read(dp);
@@ -1826,18 +1832,28 @@ write_png(struct display *dp, const char *destname)
 static void
 set_windowBits_hi(struct display *dp)
 {
-   /* windowBits is in the range 8..15, but it is said that setting '8'
-    * prevents adequate search even if the image size is 256 bytes or less.
+   /* windowBits is in the range 8..15 but zlib maps '8' to '9' so it is only
+    * worth using if the data size is 256 byte or less.
     */
    int wb = MAX_WBITS; /* for large images */
    int i = VLSIZE(windowBits_IDAT);
 
-   while (wb > 9 && dp->size <= 1U<<(wb-1)) --wb;
+   while (wb > 8 && dp->size <= 1U<<(wb-1)) --wb;
 
    while (--i >= 0) if (VLNAME(windowBits_IDAT)[i].name == range_hi) break;
 
-   assert(i > 0); /* vl_windowBits_IDAT always has a RANGE() */
+   assert(i > 1); /* vl_windowBits_IDAT always has a RANGE() */
    VLNAME(windowBits_IDAT)[i].value = wb;
+
+   assert(VLNAME(windowBits_IDAT)[--i].name == range_lo);
+   VLNAME(windowBits_IDAT)[i].value = wb > 8 ? 9 : 8;
+
+   /* If wb == 8 then any search has been restricted to just one windowBits
+    * entry.  Record that here to avoid producing a spurious app-level warning
+    * above.
+    */
+   if (wb == 8)
+      dp->min_windowBits = OPTIND(dp, windowBits);
 }
 
 static int

contrib/libtests/timepng.c

@@ -1,8 +1,8 @@
 /* timepng.c
  *
- * Copyright (c) 2013 John Cunningham Bowler
+ * Copyright (c) 2013,2016 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.1 [March 28, 2013]
+ * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -10,15 +10,17 @@
  *
  * Load an arbitrary number of PNG files (from the command line, or, if there
  * are no arguments on the command line, from stdin) then run a time test by
- * reading each file by row.  The test does nothing with the read result and
- * does no transforms.  The only output is a time as a floating point number of
- * seconds with 9 decimal digits.
+ * 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.
  */
 #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>
 
@@ -35,36 +37,61 @@
 #  include "../../png.h"
 #endif
 
-static int read_png(FILE *fp)
+/* 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 */
+
+#if ((defined(PNG_SEQUENTIAL_READ_SUPPORTED)) && defined(PNG_STDIO_SUPPORTED)\
+     && defined(PNG_EASY_ACCESS_SUPPORTED) && defined(PNG_INFO_IMAGE_SUPPORTED))
+typedef struct
 {
-   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;
+   FILE *input;
+   FILE *output;
+}  io_data;
 
-   if (png_ptr == NULL)
-      return 0;
+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 (setjmp(png_jmpbuf(png_ptr)))
+   if (fread(buffer, cb, 1, io->input) != 1)
+      png_error(png_ptr, strerror(errno));
+
+   if (fwrite(buffer, cb, 1, io->output) != 1)
    {
-      png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
-      if (row != NULL) free(row);
-      if (display != NULL) free(display);
-      return 0;
+      perror("temporary file");
+      fprintf(stderr, "temporary file PNG write failed\n");
+      exit(1);
    }
+}
 
-   png_init_io(png_ptr, fp);
+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_bytep row = NULL, display = NULL;
+   io_data io_copy;
 
-   info_ptr = png_create_info_struct(png_ptr);
-   if (info_ptr == NULL)
-      png_error(png_ptr, "OOM allocating info structure");
+   if (write_ptr != NULL)
+   {
+      /* 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_read_info(png_ptr, info_ptr);
 
    {
       png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);
 
-      row = malloc(rowbytes);
-      display = malloc(rowbytes);
+      row = voidcast(png_bytep,malloc(rowbytes));
+      display = voidcast(png_bytep,malloc(rowbytes));
 
       if (row == NULL || display == NULL)
          png_error(png_ptr, "OOM allocating row buffers");
@@ -81,7 +108,8 @@ static int read_png(FILE *fp)
             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.
+             * work, but this avoids memory thrashing for speed testing and is
+             * somewhat representative of an application that works row-by-row.
              */
             while (y-- > 0)
                png_read_row(png_ptr, row, display);
@@ -91,9 +119,51 @@ static int read_png(FILE *fp)
 
    /* Make sure to read to the end of the file: */
    png_read_end(png_ptr, info_ptr);
-   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+
+   /* Free this up: */
    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;
 }
 
@@ -108,7 +178,7 @@ static int mytime(struct timespec *t)
    return 0;
 }
 
-static int perform_one_test(FILE *fp, int nfiles)
+static int perform_one_test(FILE *fp, int nfiles, png_int_32 transforms)
 {
    int i;
    struct timespec before, after;
@@ -120,7 +190,7 @@ static int perform_one_test(FILE *fp, int nfiles)
    {
       for (i=0; i<nfiles; ++i)
       {
-         if (read_png(fp))
+         if (read_png(fp, transforms, NULL/*write*/))
          {
             if (ferror(fp))
             {
@@ -184,120 +254,343 @@ static int add_one_file(FILE *fp, char *name)
 
    if (ip != NULL)
    {
-      int ch;
-      for (;;)
+      /* 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))
       {
-         ch = getc(ip);
-         if (ch == EOF) break;
-         putc(ch, fp);
+         /* Fatal error reading the start: */
+         perror("temporary file");
+         fprintf(stderr, "temporary file fgetpos error\n");
+         exit(1);
       }
 
-      if (ferror(ip))
+      if (read_png(ip, -1/*by row*/, fp/*output*/))
       {
-         perror(name);
-         fprintf(stderr, "%s: read error\n", name);
-         return 0;
+         if (ferror(ip))
+         {
+            perror(name);
+            fprintf(stderr, "%s: read error\n", name);
+         }
+
+         else
+            ok = 1; /* read ok */
       }
 
+      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");
-         return 0;
+         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);
       }
    }
 
    else
    {
+      /* file open error: */
       perror(name);
       fprintf(stderr, "%s: open failed\n", name);
-      return 0;
    }
 
-   return 1;
+   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);
 }
 
 int main(int argc, char **argv)
 {
    int ok = 0;
-   FILE *fp = tmpfile();
+   int err = 0;
+   int nfiles = 0;
+   int transforms = -1; /* by row */
+   const char *assembly = NULL;
+   FILE *fp;
 
-   if (fp != NULL)
+   if (argc > 2 && strcmp(argv[1], "--assemble") == 0)
    {
-      int err = 0;
-      int nfiles = 0;
-
-      if (argc > 1)
+      /* Just build the test file, argv[2] is the file name. */
+      assembly = argv[2];
+      fp = fopen(assembly, "wb");
+      if (fp == NULL)
       {
-         int i;
+         perror(assembly);
+         fprintf(stderr, "timepng --assemble %s: could not open for write\n",
+               assembly);
+         usage(NULL);
+      }
 
-         for (i=1; i<argc; ++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)
          {
-            if (add_one_file(fp, argv[i]))
+            fprintf(stderr, "%s: skipped, too many files\n", argv[i]);
+            break;
+         }
+
+         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)
+            {
+               fprintf(stderr, "%s: skipped, too many files\n", filename);
+               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))
+      {
+         fprintf(stderr, "timepng: stdin: read error\n");
+         err = 1;
+      }
+   }
+
+   /* Perform the test, or produce the --assemble output: */
+   if (!err)
+   {
+      if (nfiles > 0)
+      {
+         if (assembly != NULL)
+         {
+            if (fflush(fp) && !ferror(fp) && fclose(fp))
+            {
+               perror(assembly);
+               fprintf(stderr, "%s: close failed\n", assembly);
+            }
 
             else
             {
-               err = 1;
-               break;
+               printf("%s %d\n", assembly, nfiles);
+               fflush(stdout);
+               ok = !ferror(stdout);
             }
          }
+
+         else
+         {
+            ok = perform_one_test(fp, nfiles, transforms);
+            (void)fclose(fp);
+         }
       }
 
       else
-      {
-         char filename[FILENAME_MAX+1];
-
-         while (fgets(filename, FILENAME_MAX+1, stdin))
-         {
-            size_t len = strlen(filename);
-
-            if (filename[len-1] == '\n')
-            {
-               filename[len-1] = 0;
-               if (add_one_file(fp, filename))
-                  ++nfiles;
-
-               else
-               {
-                  err = 1;
-                  break;
-               }
-            }
-
-            else
-            {
-               fprintf(stderr, "timepng: truncated file name ...%s\n",
-                  filename+len-32);
-               err = 1;
-               break;
-            }
-         }
-
-         if (ferror(stdin))
-         {
-            fprintf(stderr, "timepng: stdin: read error\n");
-            err = 1;
-         }
-      }
-
-      if (!err)
-      {
-         if (nfiles > 0)
-            ok = perform_one_test(fp, nfiles);
-
-         else
-            fprintf(stderr, "usage: timepng {files} or ls files | timepng\n");
-      }
-
-      (void)fclose(fp);
+         usage(fp);
    }
 
    else
-      fprintf(stderr, "timepng: could not open temporary file\n");
+      (void)fclose(fp);
 
    /* Exit code 0 on success. */
    return ok == 0;
 }
+#else /* !sufficient support */
+int main(void) { return 77; }
+#endif /* !sufficient support */

libpng-manual.txt

@@ -1,6 +1,6 @@
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.7.0beta79 - March 9, 2016
+ libpng version 1.7.0beta80 - May 6, 2016
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2015 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 1.7.0beta79 - March 9, 2016
+ libpng versions 0.97, January 1998, through 1.7.0beta80 - May 6, 2016
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2015 Glenn Randers-Pehrson
 
@@ -5343,7 +5343,7 @@ 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 1.7.0beta79 are Y2K compliant.  It is my belief that earlier
+upward through 1.7.0beta80 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 "March 9, 2016"
+.TH LIBPNG 3 "May 6, 2016"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0beta79
+libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0beta80
 .SH SYNOPSIS
 \fB
 #include <png.h>\fP
@@ -500,7 +500,7 @@ 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 1.7.0beta79 - March 9, 2016
+ libpng version 1.7.0beta80 - May 6, 2016
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2015 Glenn Randers-Pehrson
@@ -511,7 +511,7 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.7.0beta79 - March 9, 2016
+ libpng versions 0.97, January 1998, through 1.7.0beta80 - May 6, 2016
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2015 Glenn Randers-Pehrson
 
@@ -5843,7 +5843,7 @@ 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 1.7.0beta79 are Y2K compliant.  It is my belief that earlier
+upward through 1.7.0beta80 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
@@ -5948,7 +5948,7 @@ the first widely used release:
  1.6.19rc01-03           16    10619  16.so.16.19[.0]
  ...
  1.7.0alpha01-10         17    10700  17.so.17.0[.0]
- 1.7.0beta01-79          17    10700  17.so.17.0[.0]
+ 1.7.0beta01-80          17    10700  17.so.17.0[.0]
 
 Henceforth the source version will match the shared-library minor
 and patch numbers; the shared-library major version number will be
@@ -6004,7 +6004,7 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.7.0beta79 - March 9, 2016:
+Libpng version 1.7.0beta80 - May 6, 2016:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -6029,7 +6029,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.0.7, July 1, 2000, through 1.7.0beta79, March 9, 2016, are
+libpng versions 1.0.7, July 1, 2000, through 1.7.0beta80, May 6, 2016, are
 Copyright (c) 2000-2002, 2004, 2006-2016 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
@@ -6128,7 +6128,7 @@ the additional disclaimers inserted at version 1.0.7.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-March 9, 2016
+May 6, 2016
 
 .\" end of man page
 

libpngpf.3

@@ -1,6 +1,6 @@
-.TH LIBPNGPF 3 "March 9, 2016"
+.TH LIBPNGPF 3 "May 6, 2016"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0beta79
+libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0beta80
 (private functions)
 .SH SYNOPSIS
 \fB#include \fI"pngpriv.h"

png.5

@@ -1,4 +1,4 @@
-.TH PNG 5 "March 9, 2016"
+.TH PNG 5 "May 6, 2016"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION

png.c

@@ -15,7 +15,7 @@
 #define PNG_SRC_FILE PNG_SRC_FILE_png
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_7_0beta79 Your_png_h_is_not_version_1_7_0beta79;
+typedef png_libpng_version_1_7_0beta80 Your_png_h_is_not_version_1_7_0beta80;
 
 /* Tells libpng that we have already handled the first "num_bytes" bytes
  * of the PNG file signature.  If the PNG data is embedded into another
@@ -705,14 +705,14 @@ png_get_copyright(png_const_structrp png_ptr)
 #else
 #  ifdef __STDC__
    return PNG_STRING_NEWLINE \
-     "libpng version 1.7.0beta79 - March 9, 2016" PNG_STRING_NEWLINE \
+     "libpng version 1.7.0beta80 - May 6, 2016" PNG_STRING_NEWLINE \
      "Copyright (c) 1998-2002,2004,2006-2016 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 1.7.0beta79 - March 9, 2016\
+      return "libpng version 1.7.0beta80 - May 6, 2016\
       Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";

png.h

@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.7.0beta79, March 9, 2016
+ * libpng version 1.7.0beta80, May 6, 2016
  *
  * Copyright (c) 1998-2002,2004,2006-2016 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 1.7.0beta79, March 9, 2016:
+ *   libpng versions 0.97, January 1998, through 1.7.0beta80, May 6, 2016:
  *     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 1.7.0beta79, March 9, 2016, are
+ * libpng versions 1.0.7, July 1, 2000, through 1.7.0beta80, May 6, 2016, are
  * Copyright (c) 2000-2002, 2004, 2006-2016 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
@@ -190,7 +190,7 @@
  *    1.6.19rc01-03           16    10619  16.so.16.19[.0]
  *    ...
  *    1.7.0alpha01-10         17    10700  17.so.17.0[.0]
- *    1.7.0beta01-79          17    10700  17.so.17.0[.0]
+ *    1.7.0beta01-80          17    10700  17.so.17.0[.0]
  *
  *    Henceforth the source version will match the shared-library major
  *    and minor numbers; the shared-library major version number will be
@@ -218,13 +218,13 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    March 9, 2016
+ *    May 6, 2016
  *
  *    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 1.7.0beta79 are Y2K compliant.  It is my belief that
+ *    upward through 1.7.0beta80 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
@@ -286,9 +286,9 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.7.0beta79"
+#define PNG_LIBPNG_VER_STRING "1.7.0beta80"
 #define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.7.0beta79 - March 9, 2016\n"
+     " libpng version 1.7.0beta80 - May 6, 2016\n"
 
 #define PNG_LIBPNG_VER_SONUM   17
 #define PNG_LIBPNG_VER_DLLNUM  17
@@ -302,7 +302,7 @@
  * PNG_LIBPNG_VER_STRING, omitting any leading zero:
  */
 
-#define PNG_LIBPNG_VER_BUILD  79
+#define PNG_LIBPNG_VER_BUILD  80
 
 /* Release Status */
 #define PNG_LIBPNG_BUILD_ALPHA    1
@@ -562,7 +562,7 @@ 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_7_0beta79;
+typedef char* png_libpng_version_1_7_0beta80;
 
 /* Basic control structions.  Read libpng-manual.txt or libpng.3 for more info.
  *
@@ -1226,11 +1226,12 @@ PNG_EXPORT(241, int, png_convert_to_rfc1123_buffer, (char out[29],
 
 #ifdef PNG_CONVERT_tIME_SUPPORTED
 /* Convert from a struct tm to png_time */
-PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime,
-    const struct tm * ttime));
+PNG_EXPORT(24, PNG_DEPRECATED void, png_convert_from_struct_tm,
+      (png_timep ptime, const struct tm * ttime));
 
 /* Convert from time_t to png_time.  Uses gmtime() */
-PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime));
+PNG_EXPORT(25, PNG_DEPRECATED void, png_convert_from_time_t, (png_timep ptime,
+         time_t ttime));
 #endif /* CONVERT_tIME */
 
 #ifdef PNG_READ_EXPAND_SUPPORTED
@@ -1533,7 +1534,7 @@ PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr));
 #endif
 
 #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-#define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */
+#define PNG_READ_16_TO_8_SUPPORTED /* Name prior to 1.5.4 */
 /* Strip the second byte of information from a 16-bit depth file. */
 PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr));
 #endif
@@ -1690,25 +1691,14 @@ PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action,
  *    ignored if SUB is set; this is because these filter pairs are equivalent
  *    when there is no previous row.
  *
- * 2) PNG_SELECT_FILTER_METHODICALLY_SUPPORTED:
- *    If SELECT_FILTER_METHODICALLY is 'on' libpng tries all the filters in the
- *    list and selects the one which gives the shortest compressed row, favoring
- *    earlier filters.
+ * 2) PNG_SELECT_FILTER_SUPPORTED:
+ *    libpng will buffer rows until enough data is available to perform a
+ *    reasonable filter selection heuristic then select filters for at least the
+ *    first buffered row.
  *
- * 3) PNG_SELECT_FILTER_HEURISTICALLY_SUPPORTED:
- *    If SELECT_FILTER_HEURISTICALLY is 'on' libpng tests the start of each row
- *    (a few thousand bytes at most) to see which filter is likely to produce
- *    best compression.
- *
- * 4) If neither (2) nor (3) libpng selects the first filter in the list (there
- *    is no warning that this will happen - check the #defines if you need to
- *    know.)
- *
- * The seletion options are turned 'on' using png_set_option(method,
- * PNG_OPTION_ON) and turned off with PNG_OPTION_OFF.  If a selection method is
- * turned off it will never be used, if neither option is turned on or off (i.e.
- * if png_set_option is not called) the first supported option (2) or (3) will
- * be used.
+ * 3) !PNG_SELECT_FILTER_SUPPORTED:
+ *    libpng selects the first filter in the list (there is no warning that this
+ *    will happen - check the #defines if you need to know.)
  *
  * If you intend to use 'previous row' filters in an image set either the UP or
  * PAETH filter before the first call to png_write_row, depending on whether you
@@ -1717,12 +1707,6 @@ PNG_EXPORT(66, void, png_set_crc_action, (png_structrp png_ptr, int crit_action,
  * You can also select AVG on the first row; it uses half the value of the
  * preceding byte as a predictor and is not likely to have very good
  * performance.
- *
- * The SELECT_FILTER_METHODICALLY option is slow and memory intensive, but it is
- * almost certain to produce the smallest PNG file.  Depending on the image data
- * the HEURISTIC option may improve results significantly over the NONE filter
- * and it has little overall effect on compression speed, however it can
- * sometimes produce larger files than not using any filtering.
  */
 PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method,
     int filters));
@@ -1752,12 +1736,12 @@ PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method,
 #define PNG_FILTER_AVG         PNG_FILTER_MASK(PNG_FILTER_VALUE_AVG)
 #define PNG_FILTER_PAETH       PNG_FILTER_MASK(PNG_FILTER_VALUE_PAETH)
 
-/* Then two convenience values.  PNG_NO_FILTERS is the same as
+/* Then three convenience values.  PNG_NO_FILTERS is the same as
  * PNG_FILTER_VALUE_NONE, but this is harmless because they mean the same thing.
  */
-#define PNG_NO_FILTERS     0x00
-#define PNG_ALL_FILTERS    (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
-   PNG_FILTER_AVG | PNG_FILTER_PAETH)
+#define PNG_NO_FILTERS   0x00
+#define PNG_FAST_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP)
+#define PNG_ALL_FILTERS  (PNG_FAST_FILTERS | PNG_FILTER_AVG | PNG_FILTER_PAETH)
 
 #ifdef PNG_WRITE_SUPPORTED
 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED /* DEPRECATED */
@@ -3629,9 +3613,7 @@ PNG_EXPORT(245, int, png_image_write_to_memory, (png_imagep image, void *memory,
 #define PNG_EXTENSIONS 0 /* BOTH: enable or disable extensions */
 #define PNG_MAXIMUM_INFLATE_WINDOW 2 /* SOFTWARE: force maximum window */
 #define PNG_SKIP_sRGB_CHECK_PROFILE 4 /* SOFTWARE: Check ICC profile for sRGB */
-#define PNG_SELECT_FILTER_HEURISTICALLY 6 /* SOFTWARE: see png_set_filter */
-#define PNG_SELECT_FILTER_METHODICALLY 8 /* SOFTWARE: see png_set_filter */
-#define PNG_OPTION_NEXT  10 /* Next option - numbers must be even */
+#define PNG_OPTION_NEXT  6 /* Next option - numbers must be even */
 
 /* Return values: NOTE: there are four values and 'off' is *not* zero */
 #define PNG_OPTION_UNSET   0 /* Unset - defaults to off */

pngconf.h

@@ -1,7 +1,7 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.7.0beta79, March 9, 2016
+ * libpng version 1.7.0beta80, May 6, 2016
  *
  * Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)

pngpriv.h

@@ -1080,10 +1080,6 @@ PNG_INTERNAL_FUNCTION(int,png_crc_finish,(png_structrp png_ptr,
 PNG_INTERNAL_FUNCTION(void,png_calculate_crc,(png_structrp png_ptr,
    png_const_voidp ptr, png_size_t length),PNG_EMPTY);
 
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_flush,(png_structrp png_ptr),PNG_EMPTY);
-#endif
-
 /* Write various chunks */
 
 /* Write the IHDR chunk, and update the png_struct with the necessary
@@ -1199,9 +1195,9 @@ PNG_INTERNAL_FUNCTION(void,png_write_sCAL_s,(png_structrp png_ptr,
 #endif
 
 #ifdef PNG_WRITE_SUPPORTED
-/* Initialize the row compression mechanism. */
-PNG_INTERNAL_FUNCTION(void, png_write_start_IDAT, (png_structp png_ptr),
-   PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_write_start_IDAT,(png_structrp png_ptr),
+      PNG_EMPTY);
+   /* Do any required initialization before IDAT or row processing starts. */
 
 /* Choose the best filter to use and filter the row data then write it out.  If
  * WRITE_FILTERING is not supported this just writes the data out with a zero
@@ -1215,10 +1211,11 @@ PNG_INTERNAL_FUNCTION(void, png_write_start_IDAT, (png_structp png_ptr),
  */
 enum
 {
-   png_row_end        =0x1U, /* This is the last block in the row */
-   png_pass_first_row =0x2U, /* This is the first row in a pass */
-   png_pass_last_row  =0x4U, /* This is the last row in a pass */
-   png_pass_last      =0x8U  /* This is the last pass in the image */
+   png_pass_last      =0x1U, /* This is the last pass in the image */
+   png_pass_last_row  =0x2U, /* This is the last row in a pass */
+   png_pass_first_row =0x4U, /* This is the first row in a pass */
+   png_row_end        =0x8U, /* This is the last block in the row */
+   png_no_row_info    =0x0U  /* Placeholder */
 
    /* A useful macro; return true if this is the last block of the last row in
     * the image.
@@ -1226,11 +1223,21 @@ enum
 #  define PNG_IDAT_END(f) (((f) & ~png_pass_first_row) == \
       (png_row_end+png_pass_last_row+png_pass_last))
 };
-PNG_INTERNAL_FUNCTION(void, png_write_filter_row, (png_structrp png_ptr,
+PNG_INTERNAL_FUNCTION(void,png_write_png_data,(png_structrp png_ptr,
     png_bytep prev_pixels, png_const_bytep unfiltered_row, png_uint_32 x,
     unsigned int width/*pixels*/, unsigned int row_info_flags),
    PNG_EMPTY);
 
+PNG_INTERNAL_FUNCTION(void,png_write_png_rows,(png_structrp png_ptr,
+    png_const_bytep *rows, png_uint_32 num_rows), PNG_EMPTY);
+   /* As above but rows[num_rows] of correctly (PNG) formated but unfiltered
+    * data are passed in.  For an interlaced image the rows will be interlaced
+    * rows and therefore may be narrower than the image width.
+    *
+    * This function advances png_structp::pass and png_structp::row_number as
+    * required.
+    */
+
 /* Release memory used by the deflate mechanism */
 PNG_INTERNAL_FUNCTION(void, png_deflate_destroy, (png_structp png_ptr),
    PNG_EMPTY);

pngstruct.h

@@ -26,14 +26,14 @@
 #ifndef ZLIB_CONST
    /* We must ensure that zlib uses 'const' in declarations. */
 #  define ZLIB_CONST
-#endif
+#endif /* !ZLIB_CONST */
 
 #include PNG_ZLIB_HEADER
 
 #ifdef const
    /* zlib.h sometimes #defines const to nothing, undo this. */
 #  undef const
-#endif
+#endif /* const */
 
 /* zlib.h has mediocre z_const use before 1.2.6, this stuff is for compatibility
  * with older builds.
@@ -41,10 +41,10 @@
 #if ZLIB_VERNUM < 0x1260
 #  define PNGZ_MSG_CAST(s) png_constcast(char*,s)
 #  define PNGZ_INPUT_CAST(b) png_constcast(png_bytep,b)
-#else
+#else /* ZLIB_VERNUM >= 0x1260 */
 #  define PNGZ_MSG_CAST(s) (s)
 #  define PNGZ_INPUT_CAST(b) (b)
-#endif
+#endif /* ZLIB_VERNUM >= 0x1260 */
 
 /* zlib.h declares a magic type 'uInt' that limits the amount of data that zlib
  * can handle at once.  This type need be no larger than 16 bits (so maximum of
@@ -57,17 +57,17 @@
 #ifndef ZLIB_IO_MAX
 #  ifdef __COVERITY__
 #     define ZLIB_IO_MAX ((uInt)255U) /* else COVERITY whines */
-#  else
+#  else /* !COVERITY */
 #     define ZLIB_IO_MAX ((uInt)-1)
-#  endif /* COVERITY */
-#endif
+#  endif /* !COVERITY */
+#endif /* !ZLIB_IO_MAX */
 
 #ifdef PNG_WRITE_SUPPORTED
 /* The write compression control (allocated on demand).
  * TODO: use this for the read state too.
  */
 typedef struct png_zlib_state *png_zlib_statep;
-#endif
+#endif /* WRITE */
 
 /* Colorspace support; structures used in png_struct, png_info and in internal
  * functions to hold and communicate information about the color space.
@@ -114,13 +114,13 @@ typedef struct png_colorspace
 {
 #ifdef PNG_GAMMA_SUPPORTED
    png_fixed_point gamma;        /* File gamma */
-#endif
+#endif /* GAMMA */
 
 #ifdef PNG_COLORSPACE_SUPPORTED
    png_xy      end_points_xy;    /* End points as chromaticities */
    png_XYZ     end_points_XYZ;   /* End points as CIE XYZ colorant values */
    png_uint_16 rendering_intent; /* Rendering intent of a profile */
-#endif
+#endif /* COLORSPACE */
 
    /* Flags are always defined to simplify the code. */
    png_uint_16 flags;            /* As defined below */
@@ -182,7 +182,7 @@ typedef struct
        * during PNG_TC_INIT_FINAL.  The field is only used on read; write
        * transforms do not modify the gamma of the data.
        */
-#  endif
+#  endif /* READ_GAMMA */
    unsigned int       format;       /* As pngstruct::row_format below */
    unsigned int       range;        /* Count of range transforms */
 #  define PNG_TC_CHANNELS(tc) PNG_FORMAT_CHANNELS((tc).format)
@@ -364,7 +364,7 @@ struct png_struct_def
     * accessed.)
     */
    jmp_buf jmp_buf_local;
-#endif
+#endif /* SETJMP */
 
    /* Next the frequently accessed fields.  Many processors perform arithmetic
     * in the address pipeline, but frequently the amount of addition or
@@ -420,7 +420,7 @@ struct png_struct_def
    /* Options */
 #ifdef PNG_SET_OPTION_SUPPORTED
    png_uint_32 options;       /* On/off state (up to 16 options) */
-#endif
+#endif /* SET_OPTIONS */
 
 #ifdef PNG_READ_SUPPORTED
 #if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED)
@@ -428,13 +428,13 @@ struct png_struct_def
     * is in (just) the info_struct.
     */
    png_colorspace   colorspace;
-#endif
+#endif /* COLORSPACE || GAMMA */
 #endif /* READ */
 
    /* Transform handling */
 #ifdef PNG_TRANSFORM_MECH_SUPPORTED
    png_transformp transform_list; /* List of transformation to perform. */
-#endif
+#endif /* TRANSFORM_MECH */
 
    /* ROW BUFFERS and CONTROL
     *
@@ -442,9 +442,9 @@ struct png_struct_def
     * filter byte (which is in next_filter.)  All fields are only used during
     * IDAT processing and start of 0.
     */
-#if defined(PNG_WRITE_FILTER_SUPPORTED) || defined(PNG_READ_SUPPORTED)
+#ifdef PNG_READ_SUPPORTED
    png_bytep        row_buffer;          /* primary row buffer */
-#endif /* WRITE_FILTER || READ */
+#endif /* READ */
 #if (defined(PNG_PROGRESSIVE_READ_SUPPORTED) ||\
      defined(PNG_READ_INTERLACING_SUPPORTED)) &&\
     defined(PNG_TRANSFORM_MECH_SUPPORTED)
@@ -482,10 +482,12 @@ struct png_struct_def
    unsigned int invalid_info;      /* PNG_INFO_* for invalidated chunks */
    unsigned int palette_updated:1; /* png_struct::palette changed */
 #endif /* READ_TRANSFORMS */
-
+#ifdef PNG_WRITE_SUPPORTED
+   unsigned int write_rows     :1; /* libpng has complete rows to write */
+#endif /* WRITE */
 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
    unsigned int read_started   :1; /* at least one call to png_read_row */
-#endif
+#endif /* SEQUENTIAL_READ */
 #if defined (PNG_READ_INTERLACING_SUPPORTED) ||\
     defined (PNG_WRITE_INTERLACING_SUPPORTED)
    unsigned int do_interlace   :1; /* libpng handles the interlace */
@@ -574,7 +576,7 @@ struct png_struct_def
     * available to zlib during read decompression.
     */
    png_alloc_size_t read_buffer_size; /* current size of the buffer */
-#endif
+#endif /* READ */
 
 #if defined(PNG_SEQUENTIAL_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
    png_uint_32 IDAT_size;         /* limit on IDAT read and write IDAT size */
@@ -585,13 +587,13 @@ struct png_struct_def
    jmp_buf        *jmp_buf_ptr;   /* passed to longjmp_fn */
    png_longjmp_ptr longjmp_fn;    /* setjmp non-local goto function. */
    size_t          jmp_buf_size;  /* size of *jmp_buf_ptr, if allocated */
-#endif
+#endif /* SETJMP */
 
    /* Error/warning callbacks */
    png_error_ptr error_fn;        /* print an error message and abort */
 #ifdef PNG_WARNINGS_SUPPORTED
    png_error_ptr warning_fn;      /* print a warning and continue */
-#endif
+#endif /* WARNINGS */
    png_voidp     error_ptr;       /* user supplied data for the above */
 
    /* MEMORY ALLOCATION */
@@ -599,7 +601,7 @@ struct png_struct_def
    png_malloc_ptr malloc_fn; /* allocate memory */
    png_free_ptr   free_fn;   /* free memory */
    png_voidp      mem_ptr;   /* user supplied data for the above */
-#endif
+#endif /* USER_MEM */
 
    /* IO and BASIC READ/WRITE SUPPORT */
    png_voidp            io_ptr;       /* user supplied data for IO callbacks */
@@ -622,8 +624,7 @@ struct png_struct_def
 
 #ifdef PNG_WRITE_FLUSH_SUPPORTED
    png_flush_ptr output_flush_fn; /* Function for flushing output */
-#endif
-
+#endif /* WRITE_FLUSH */
 #endif /* WRITE */
 
 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
@@ -634,14 +635,14 @@ struct png_struct_def
     * - it is decremented as memory is allocated.
     */
    png_alloc_size_t user_chunk_malloc_max;
-#endif
+#endif /* SET_USER_LIMITS */
 #ifdef PNG_USER_LIMITS_SUPPORTED
    /* limit on total *number* of sPLT, text and unknown chunks that can be
     * stored.  0 means unlimited.  This field is a counter - it is decremented
     * as chunks are encountered.
     */
    png_uint_32 user_chunk_cache_max;
-#endif
+#endif /* USER_LIMITS */
 
    /* The progressive reader gets passed data and calls application handling
     * functions when appropriate.
@@ -672,7 +673,7 @@ struct png_struct_def
 
 #ifdef PNG_IO_STATE_SUPPORTED
    png_uint_32          io_state;     /* tells the app read/write progress */
-#endif
+#endif /* IO_STATE */
 
    /* UNKNOWN CHUNK HANDLING */
    /* TODO: this is excessively complicated, there are multiple ways of doing
@@ -686,12 +687,12 @@ struct png_struct_def
     * set_unknown_chunks interface.)
     */
    png_voidp user_chunk_ptr;
-#endif
+#endif /* USER_CHUNKS */
 
 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
    /* This is called back from the unknown chunk handling */
    png_user_chunk_ptr     read_user_chunk_fn; /* user read chunk handler */
-#endif
+#endif /* READ_USER_CHUNKS */
 
 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
    png_uint_32  known_unknown;   /* Bit mask of known chunks to be treated as
@@ -703,7 +704,7 @@ struct png_struct_def
                                   * 'known & ~save'.
                                   */
 #  define png_IDATs_skipped(pp) (((pp)->known_unknown & ~(pp)->save_unknown)&1U)
-#else
+#else /* !SAVE_UNKNOWN_CHUNKS */
 #  define png_IDATs_skipped(pp) ((pp)->known_unknown & 1U)
 #endif /* !SAVE_UNKNOWN_CHUNKS */
 #endif /* HANDLE_AS_UNKNOWN */
@@ -713,7 +714,7 @@ struct png_struct_def
                                   * followed by a PNG_HANDLE_* byte */
    unsigned int unknown_default :2; /* As PNG_HANDLE_* */
    unsigned int num_chunk_list;  /* Number of entries in the list */
-#endif
+#endif /* SET_UNKNOWN_CHUNKS */
 
    /* COMPRESSION AND DECOMPRESSION SUPPORT.
     *
@@ -738,7 +739,7 @@ struct png_struct_def
    /* MNG SUPPORT */
 #ifdef PNG_MNG_FEATURES_SUPPORTED
    unsigned int mng_features_permitted :3;
-#endif
+#endif /* MNG_FEATURES */
 
    /* SCRATCH buffers, used when control returns to the application or a read
     * loop.

pngtest.c

@@ -2070,4 +2070,4 @@ main(void)
 #endif
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_7_0beta79 Your_png_h_is_not_version_1_7_0beta79;
+typedef png_libpng_version_1_7_0beta80 Your_png_h_is_not_version_1_7_0beta80;

pngwio.c

@@ -67,18 +67,7 @@ png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
 }
 #endif
 
-/* This function is called to output any data pending writing (normally
- * to disk).  After png_flush is called, there should be no data pending
- * writing in any buffers.
- */
 #ifdef PNG_WRITE_FLUSH_SUPPORTED
-void /* PRIVATE */
-png_flush(png_structrp png_ptr)
-{
-   if (png_ptr->output_flush_fn != NULL)
-      png_ptr->output_flush_fn(png_ptr);
-}
-
 #  ifdef PNG_STDIO_SUPPORTED
 void PNGCBAPI
 png_default_flush(png_structp png_ptr)

pngwrite.c

@@ -487,7 +487,8 @@ png_write_end(png_structrp png_ptr, png_inforp info_ptr)
     */
 #  ifdef PNG_WRITE_FLUSH_SUPPORTED
 #     ifdef PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED
-         png_flush(png_ptr);
+         if (png_ptr->output_flush_fn != NULL)
+            png_ptr->output_flush_fn(png_ptr);
 #     endif
 #  endif
 }
@@ -570,65 +571,6 @@ png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
 }
 
 
-/* Write a few rows of image data.  If the image is interlaced,
- * either you will have to write the 7 sub images, or, if you
- * have called png_set_interlace_handling(), you will have to
- * "write" the image seven times.
- */
-void PNGAPI
-png_write_rows(png_structrp png_ptr, png_bytepp row,
-    png_uint_32 num_rows)
-{
-   png_debug(1, "in png_write_rows");
-
-   if (png_ptr == NULL || row == NULL)
-      return;
-
-   /* Loop through the rows */
-   while (num_rows-- > 0)
-      png_write_row(png_ptr, *row++);
-}
-
-/* Write the image.  You only need to call this function once, even
- * if you are writing an interlaced image.
- */
-void PNGAPI
-png_write_image(png_structrp png_ptr, png_bytepp image)
-{
-   int num_pass; /* pass variables */
-
-   if (png_ptr == NULL || image == NULL)
-      return;
-
-   png_debug(1, "in png_write_image");
-
-#ifdef PNG_WRITE_INTERLACING_SUPPORTED
-   /* Initialize interlace handling.  If image is not interlaced,
-    * this will set pass to 1
-    */
-   num_pass = png_set_interlace_handling(png_ptr);
-#else
-   num_pass = 1;
-
-   if (png_ptr->interlaced)
-   {
-      png_app_error(png_ptr, "no interlace support");
-      return;
-   }
-#endif
-
-   /* Loop through passes */
-   while (num_pass-- > 0)
-   {
-      png_bytepp  rp = image; /* points to current row */
-      png_uint_32 num_rows = png_ptr->height;
-
-      /* Loop through image */
-      while (num_rows-- > 0)
-         png_write_row(png_ptr, *rp++);
-   }
-}
-
 #if defined(PNG_WRITE_INTERLACING_SUPPORTED) ||\
     defined(PNG_WRITE_TRANSFORMS_SUPPORTED)
 static void
@@ -707,10 +649,10 @@ write_row_buffered(png_structrp png_ptr,
          }
 #     endif /* WRITE_TRANSFORMS */
 
-      /* Call png_write_filter_row to write this block of data, the test on
+      /* Call png_write_png_data to write this block of data, the test on
        * maxpixels says if this is the final block in the row.
        */
-      png_write_filter_row(png_ptr, prev_pixels, pixel_buffer.buffer, x,
+      png_write_png_data(png_ptr, prev_pixels, pixel_buffer.buffer, x,
             max_pixels, row_info_flags);
    }
 }
@@ -824,47 +766,7 @@ interlace_row_byte(png_const_structrp png_ptr, png_bytep dp, png_const_bytep sp,
 }
 #endif /* WRITE_INTERLACING */
 
-static void
-write_row_unbuffered(png_structrp png_ptr, png_const_bytep row,
-      unsigned int row_info_flags)
-{
-   /* Split the row into blocks of the appropriate size: */
-   const unsigned int input_depth = png_ptr->row_input_pixel_depth;
-   unsigned int max_pixels = png_max_pixel_block(png_ptr);
-   png_uint_32 max_bytes = max_pixels;
-   const unsigned int pass = png_ptr->pass;
-   const png_uint_32 width = png_ptr->interlaced == PNG_INTERLACE_NONE ?
-      png_ptr->width : PNG_PASS_COLS(png_ptr->width, pass);
-   png_uint_32 x;
-   png_byte prev_pixels[4*2*2]; /* 2 pixels up to 4 2-byte channels each */
-
-   /* max_pixels is at most 16 bits, input_depth is at most 64, so the product
-    * always fits in 32 bits:
-    */
-   max_bytes *= input_depth; /* bits */
-   debug(input_depth <= 64 && (max_bytes & 7U) == 0U);
-   max_bytes >>= 3;
-
-   memset(prev_pixels, 0U, sizeof prev_pixels);
-
-   for (x = 0U; x < width; x += max_pixels, row += max_bytes)
-   {
-      if (max_pixels > width - x)
-      {
-         max_bytes = width - x;
-         max_pixels = (unsigned int)/*SAFE*/max_bytes;
-         max_bytes = (max_bytes * input_depth + 7U) >> 3;
-      }
-
-      debug((row_info_flags & png_row_end) == 0U); /* must be set here at end */
-      if (x + max_pixels >= width)
-         row_info_flags |= png_row_end;
-
-      png_write_filter_row(png_ptr, prev_pixels, row, x, max_pixels,
-            row_info_flags);
-   }
-}
-
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
 static void
 write_row_core(png_structrp png_ptr, png_const_bytep row,
       unsigned int row_info_flags)
@@ -880,7 +782,8 @@ write_row_core(png_structrp png_ptr, png_const_bytep row,
    /* If control reaches this point the intermediate buffer is not required and
     * the input data can be used unmodified.
     */
-   write_row_unbuffered(png_ptr, row, row_info_flags);
+   png_write_png_rows(png_ptr, &row, 1U);
+   PNG_UNUSED(row_info_flags)
 }
 
 /* Write a single non-interlaced row. */
@@ -888,75 +791,53 @@ static void
 write_row_non_interlaced(png_structrp png_ptr, png_const_bytep row)
 {
    const png_uint_32 row_number = png_ptr->row_number+1U;
-   const int last_pass_row = row_number == png_ptr->height;
-
    /* There is only one pass, so this is the last pass: */
-   write_row_core(png_ptr, row,
-         (row_number == 1U ? png_pass_first_row : 0) |
-         (last_pass_row ? png_pass_last_row : 0) |
-         png_pass_last);
+   const unsigned int row_info_flags =
+      (row_number == 1U ? png_pass_first_row : 0) |
+      (row_number >= png_ptr->height ? png_pass_last_row : 0) |
+      png_pass_last;
 
-   if (!last_pass_row)
-      png_ptr->row_number = row_number;
+   debug(png_ptr->interlaced == PNG_INTERLACE_NONE);
 
-   else
-   {
-      png_ptr->row_number = 0U;
-      png_ptr->pass = 7U;
-   }
+   write_row_core(png_ptr, row, row_info_flags);
 }
 
 /* Write a single interlaced row. */
 static void
 write_row_interlaced(png_structrp png_ptr, png_const_bytep row)
 {
-   /* row_number is the row in the pass.  The app must only call png_write_row
-    * the correct number of times.  'pass' is set to 7U after the end.
-    */
    const png_uint_32 row_number = png_ptr->row_number+1U;
-   unsigned int pass = png_ptr->pass;
-   const int last_pass_row = row_number == PNG_PASS_ROWS(png_ptr->height, pass);
+   const png_uint_32 height = png_ptr->height;
+   const unsigned int pass = png_ptr->pass;
+   const unsigned int row_info_flags =
+      (row_number == 1U ? png_pass_first_row : 0) |
+      (row_number == PNG_PASS_ROWS(height, pass) ? png_pass_last_row : 0) |
+      (pass == PNG_LAST_PASS(png_ptr->width, height) ? png_pass_last : 0);
 
-   write_row_core(png_ptr, row,
-         (row_number == 1U ? png_pass_first_row : 0) |
-         (last_pass_row ? png_pass_last_row : 0) |
-         (pass == PNG_LAST_PASS(png_ptr->width, png_ptr->height) ?
-                                png_pass_last : 0));
+#  ifdef PNG_WRITE_INTERLACING_SUPPORTED
+      /* Check that libpng is not doing the interlace: */
+      debug(png_ptr->interlaced != PNG_INTERLACE_NONE &&
+            !png_ptr->do_interlace);
+#  endif /* WRITE_INTERLACING */
 
-   if (!last_pass_row)
-      png_ptr->row_number = row_number;
-
-   else
-   {
-      png_ptr->row_number = 0U;
-
-      do
-         ++pass;
-      while (pass < 7U &&
-             !PNG_PASS_IN_IMAGE(png_ptr->width, png_ptr->height, pass));
-
-      png_ptr->pass = 0x7U & pass;
-   }
+   write_row_core(png_ptr, row, row_info_flags);
 }
+#endif /* WRITE_TRANSFORMS */
 
 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
 /* Interlace a row then write it out. */
-static int
+static void
 interlace_row(png_structrp png_ptr, png_const_bytep row)
 {
-   /* row_number is in the image, it may not be in the pass and, likewise, the
-    * pass may not exist.
-    */
+   /* The row may not exist in the image (for this pass). */
    const png_uint_32 row_number = png_ptr->row_number; /* in image */
    const unsigned int pass = png_ptr->pass;
-   const int write_row = png_ptr->width > PNG_PASS_START_COL(pass) &&
-                         PNG_ROW_IN_INTERLACE_PASS(row_number, pass);
 
-   if (write_row)
+   if (png_ptr->width > PNG_PASS_START_COL(pass) &&
+       PNG_ROW_IN_INTERLACE_PASS(row_number, pass))
    {
       const unsigned int row_info_flags =
-         (row_number == PNG_PASS_START_ROW(pass) ?
-            png_pass_first_row : 0) |
+         (row_number == PNG_PASS_START_ROW(pass) ? png_pass_first_row : 0) |
          (PNG_LAST_PASS_ROW(row_number, pass, png_ptr->height) ?
             png_pass_last_row : 0) |
          (pass == PNG_LAST_PASS(png_ptr->width, png_ptr->height) ?
@@ -991,79 +872,214 @@ interlace_row(png_structrp png_ptr, png_const_bytep row)
                      interlace_row_byte, input_depth >> 3);
                break;
          }
-      }
+      } /* pass < 6 */
 
-      else /* pass 6; no interlacing required */
+      else /* pass 6: no interlacing required */
          write_row_core(png_ptr, row, row_info_flags);
    }
 
-   if (row_number+1U < png_ptr->height)
-      png_ptr->row_number = row_number+1U;
-
    else
    {
-      png_ptr->row_number = 0U;
-      png_ptr->pass = 0x7U & (pass+1U);
-   }
+      /* This code must advance row_number/pass itself; the row has been
+       * skipped.
+       */
+      if (row_number+1U < png_ptr->height)
+         png_ptr->row_number = row_number+1U;
 
-   return write_row;
+      else
+      {
+         png_ptr->row_number = 0U;
+         png_ptr->pass = 0x7U & (pass+1U);
+      }
+   }
 }
 #endif /* WRITE_INTERLACING */
 
-/* Called by user to write a row of image data */
-void PNGAPI
-png_write_row(png_structrp png_ptr, png_const_bytep row)
+/* Bottleneck API to actually write a number of rows, only exists because the
+ * rows parameter to png_write_rows is wrong.
+ */
+static void
+png_write_rows_internal(png_structrp png_ptr, png_const_bytep *rows,
+      png_uint_32 num_rows)
 {
-   if (png_ptr != NULL)
+   if (png_ptr != NULL && num_rows > 0U && rows != NULL)
    {
-      const unsigned int pass = png_ptr->pass;
-      const png_uint_32 row_number = png_ptr->row_number;
-
       /* Unlike the read code initialization happens automatically: */
-      if (row_number == 0 && pass == 0)
-         png_write_start_IDAT(png_ptr); /* doesn't change row/pass/width */
+      if (png_ptr->row_number == 0U && png_ptr->pass == 0U)
+      {
+         png_init_row_info(png_ptr);
 
-      else if (pass == 7U) /* too many calls; write already ended */
+#        ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
+         /* If the app takes a png_info from a read operation and if the app has
+          * performed transforms on the data the png_info can contain IHDR
+          * information that cannot be represented in PNG.  The code that writes
+          * the IHDR takes the color type from the png_info::format.  The app
+          * adds transforms, before or after writing the IHDR, then the IHDR
+          * color_type stored in png_struct::color_type is used in
+          * png_init_row_info above to work out the actual row format.
+          *
+          * Prior to 1.7.0 this was not verified (there was no easy way to do
+          * so).  Now we can check it here, however this is an:
+          *
+          * API CHANGE: in 1.7.0 an error may be flagged against bogus
+          * info_struct formats even though the app had removed them itself.
+          * It's just a warning at present.
+          *
+          * The test is that either the row_format produced by the write
+          * transforms exactly matches that in the original info_struct::format
+          * or that the info_struct::format was a simple mapping of the
+          * color_type that ended up in the IHDR:
+          */
+         if (png_ptr->row_format != png_ptr->info_format &&
+             PNG_FORMAT_FROM_COLOR_TYPE(png_ptr->color_type) !=
+               png_ptr->info_format)
+            png_app_warning(png_ptr, "info_struct format does not match IHDR");
+#        endif /* WRITE_TRANSFORMS */
+
+         /* Perform initialization required before IDATs are written. */
+         png_write_start_IDAT(png_ptr);
+      }
+
+      else if (png_ptr->pass >= 7U) /* too many calls; write already ended */
       {
          debug(png_ptr->row_number == 0U);
          png_app_error(png_ptr, "Too many calls to png_write_row");
          return;
       }
 
-      /* Make sure there is a row to write: */
-      if (row == NULL)
-      {
-         png_app_error(png_ptr, "NULL row pointer to png_write_row");
-         return;
-      }
-
-      if (png_ptr->interlaced == PNG_INTERLACE_NONE)
-         write_row_non_interlaced(png_ptr, row);
+      /* The remainder of these tests detect internal errors in libpng */
+      else if (png_ptr->interlaced == PNG_INTERLACE_NONE)
+         affirm(png_ptr->row_number < png_ptr->height && png_ptr->pass == 0U);
 
 #     ifdef PNG_WRITE_INTERLACING_SUPPORTED
-         /* Optional: libpng does the interlacing, app passes every row of the
-          * image the required number of times.
-          */
-         else if (png_ptr->do_interlace != 0U)
-         {
-            if (!interlace_row(png_ptr, row))
-               return; /* row skipped; skip the write callback */
-         }
-#     endif
+         else if (png_ptr->do_interlace)
+            affirm(png_ptr->row_number < png_ptr->height);
+#     endif /* WRITE_INTERLACING */
 
-      else /* app does the interlacing */
-         write_row_interlaced(png_ptr, row);
+      else /* app does interlace */
+         affirm(
+            PNG_PASS_IN_IMAGE(png_ptr->width, png_ptr->height, png_ptr->pass) &&
+            png_ptr->row_number < PNG_PASS_ROWS(png_ptr->height, png_ptr->pass)
+         );
 
-      /* API CHANGE: 1.7.0: this is now called after png_struct::row_number and
-       * png_struct::pass have been updated and, at the end of the image, after
-       * the deflate stream has been closed.  The order of the call with respect
-       * to the flush operation has also changed.  The callback can't discover
-       * any of this unless it relies on the write callbacks to find the row
-       * data, and that was never predictable.
+      /* First handle rows that require buffering because of the need to
+       * interlace them or the need to perform write transforms.
        */
-      if (png_ptr->write_row_fn != NULL)
-         (*(png_ptr->write_row_fn))(png_ptr, row_number, pass);
-   } /* png_ptr != NULL */
+#     ifdef PNG_WRITE_INTERLACING_SUPPORTED
+         /* libpng is doing the interlacing, but this only makes a difference to
+          * the first six passes (numbered, in libpng, 0..5); the seventh pass
+          * (numbered 6 by libpng) consists of complete image rows.
+          */
+         if (png_ptr->do_interlace) while (num_rows > 0U && png_ptr->pass < 6)
+            interlace_row(png_ptr, *rows++), --num_rows;
+#     endif /* WRITE_INTERLACING */
+
+#     ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
+         /* Transforms required however the row interlacing has already been
+          * handled and we have a complete (PNG) row.
+          */
+         if (png_ptr->transform_list != NULL)
+         {
+            if (png_ptr->interlaced == PNG_INTERLACE_NONE)
+               while (num_rows > 0U)
+                  write_row_non_interlaced(png_ptr, *rows++), --num_rows;
+
+#           ifdef PNG_WRITE_INTERLACING_SUPPORTED
+               else if (png_ptr->do_interlace)
+                  while (num_rows > 0U)
+                     interlace_row(png_ptr, *rows++), --num_rows;
+#           endif /* WRITE_INTERLACING */
+
+            else /* app does the interlacing */
+               while (num_rows > 0U)
+                  write_row_interlaced(png_ptr, *rows++), --num_rows;
+         }
+#     endif /* WRITE_TRANSFORMS */
+
+      /* Finally handle any remaining rows that require no (libpng) interlace
+       * and no transforms.
+       */
+      if (num_rows > 0U)
+         png_write_png_rows(png_ptr, rows, num_rows);
+
+      /* Repeat the checks above, but allow for end-of-image. */
+      if (png_ptr->pass < 7U)
+      {
+         if (png_ptr->interlaced == PNG_INTERLACE_NONE)
+            affirm(png_ptr->row_number < png_ptr->height &&
+                   png_ptr->pass == 0U);
+
+#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
+            else if (png_ptr->do_interlace)
+               affirm(png_ptr->row_number < png_ptr->height);
+#        endif /* WRITE_INTERLACING */
+
+         else /* app does interlace */
+            affirm(PNG_PASS_IN_IMAGE(png_ptr->width, png_ptr->height,
+                                     png_ptr->pass) &&
+                   png_ptr->row_number <
+                     PNG_PASS_ROWS(png_ptr->height, png_ptr->pass));
+      }
+   } /* png_ptr, rows, num_rows all valid */
+
+   else if (png_ptr != NULL)
+      png_app_warning(png_ptr, "Missing rows to row write API");
+}
+
+/* ROW WRITE APIs */
+/* Called by user to write a single row of image data */
+void PNGAPI
+png_write_row(png_structrp png_ptr, png_const_bytep row)
+{
+   png_debug(1, "in png_write_row");
+   png_write_rows_internal(png_ptr, &row, 1U);
+}
+
+/* Write a few rows of image data.  If the image is interlaced,
+ * either you will have to write the 7 sub images, or, if you
+ * have called png_set_interlace_handling(), you will have to
+ * "write" the image seven times.
+ */
+void PNGAPI
+png_write_rows(png_structrp png_ptr, png_bytepp rows, png_uint_32 num_rows)
+{
+   png_debug(1, "in png_write_rows");
+
+   if (png_ptr != NULL)
+      png_write_rows_internal(png_ptr, png_constcast(png_const_bytep*,rows),
+            num_rows);
+}
+
+/* Write the image.  You only need to call this function once, even
+ * if you are writing an interlaced image.
+ */
+void PNGAPI
+png_write_image(png_structrp png_ptr, png_bytepp image)
+{
+   png_debug(1, "in png_write_image");
+
+   if (png_ptr != NULL)
+   {
+      int num_pass = 1;
+
+      /* The image is always an non-interlaced image.  To write it as interlaced
+       * interlace handling must be present:
+       */
+      if (png_ptr->interlaced)
+      {
+#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
+            num_pass = png_set_interlace_handling(png_ptr);
+#        else /* !WRITE_INTERLACING */
+            /* There is no recovery because the IHDR has already been written.
+             */
+            png_error(png_ptr, "No interlace support");
+#        endif /* !WRITE_INTERLACING */
+      }
+
+      /* And write the whole thing, 7 times if interlacing it: */
+      for (; num_pass > 0; --num_pass)
+         png_write_rows(png_ptr, image, png_ptr->height);
+   }
 }
 
 /* Free any memory used in png_ptr struct without freeing the struct itself. */
@@ -1074,10 +1090,6 @@ png_write_destroy(png_structrp png_ptr)
 
    png_deflate_destroy(png_ptr);
 
-#ifdef PNG_WRITE_FILTER_SUPPORTED
-   png_free(png_ptr, png_ptr->row_buffer);
-   png_ptr->row_buffer = NULL;
-#endif /* WRITE_FILTER */
 #ifdef PNG_TRANSFORM_MECH_SUPPORTED
    png_transform_free(png_ptr, &png_ptr->transform_list);
 #endif

projects/vstudio/README.txt

@@ -1,7 +1,7 @@
 
 VisualStudio instructions
 
-libpng version 1.7.0beta79 - March 9, 2016
+libpng version 1.7.0beta80 - May 6, 2016
 
 Copyright (c) 2010,2013,2015 Glenn Randers-Pehrson
 

projects/vstudio/zlib.props

@@ -2,7 +2,7 @@
 <!--
  * zlib.props - location of zlib source
  *
- * libpng version 1.7.0beta79 - March 9, 2016
+ * libpng version 1.7.0beta80 - May 6, 2016
  *
  * Copyright (c) 2011,2013,2014 Glenn Randers-Pehrson
  *

scripts/README.txt

@@ -1,9 +1,9 @@
 
-Makefiles for  libpng version 1.7.0beta79 - March 9, 2016
+Makefiles for  libpng version 1.7.0beta80 - May 6, 2016
 
 pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.linux    =>  Linux/ELF makefile
-                       (gcc, creates libpng17.so.17.1.7.0beta79)
+                       (gcc, creates libpng17.so.17.1.7.0beta80)
  makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a)
  makefile.knr      =>  Archaic UNIX Makefile that converts files with
                        ansi2knr (Requires ansi2knr.c from
@@ -33,12 +33,12 @@ 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 libpng17.so.17.1.7.0beta79)
+                       creates libpng17.so.17.1.7.0beta80)
  makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
  makefile.solaris  =>  Solaris 2.X makefile (gcc,
-                       creates libpng17.so.17.1.7.0beta79)
+                       creates libpng17.so.17.1.7.0beta80)
  makefile.so9      =>  Solaris 9 makefile (gcc,
-                       creates libpng17.so.17.1.7.0beta79)
+                       creates libpng17.so.17.1.7.0beta80)
  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 1.7.0beta79"
+PNG_DFN ";Version 1.7.0beta80"
 
 #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=1.7.0beta79
+version=1.7.0beta80
 prefix=""
 libdir=""
 libs=""

scripts/libpng.pc.in

@@ -5,6 +5,6 @@ includedir=@includedir@/libpng17
 
 Name: libpng
 Description: Loads and saves PNG files
-Version: 1.7.0beta79
+Version: 1.7.0beta80
 Libs: -L${libdir} -lpng17
 Cflags: -I${includedir}

scripts/makefile.ne12bsd

@@ -17,7 +17,7 @@ INCSDIR=${LOCALBASE}/include/libpng17
 
 LIB=	png17
 SHLIB_MAJOR=	0
-SHLIB_MINOR=	1.7.0beta79
+SHLIB_MINOR=	1.7.0beta80
 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=	17
-SHLIB_MINOR=	1.7.0beta79
+SHLIB_MINOR=	1.7.0beta80
 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=	17
-SHLIB_MINOR=	1.7.0beta79
+SHLIB_MINOR=	1.7.0beta80
 
 LIB=	png
 SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \

scripts/pnglibconf.dfa

@@ -930,20 +930,36 @@ option CONVERT_tIME requires WRITE_ANCILLARY_CHUNKS
 #     png_set_filter interface allowing the application to select the filter
 #     used for each row.
 #
-#  SELECT_FILTER_HEURISTICALLY
-#     Enables code to cause libpng to choose a filter from a set passed to
-#     png_set_filter.  Without this code libpng just chooses the first filter in
-#     the list if multiple are given.
+#  SELECT_FILTER
+#     Enables code to select between multiple filters on write.  Without this
+#     the 'first' (lowest numbered) filter will be selected an this typically
+#     works out as PNG_FILTER_VALUE_NONE.
 #
-#  SELECT_FILTER_METHODICALLY
-#     Enables code to try all the filters in the list passed to png_set_filter
-#     and choose the one which results in the least number of compressed bytes
-#     added by the current row.
+#  COMPRESSION_BUFFER_MAX
+#     WARNING: take care if you set this.  This is the maximum amount of input
+#     data that the implementation of deflate can consume before it outputs a
+#     Huffman table for that data.  I.e. before it commits to an encoding of the
+#     data it has read.  This is used solely to implement a limit on the amount
+#     of image data buffering that occurs inside libpng before filter selection
+#     is done.  Normally the limit is never reached because of the next setting,
+#     but this is a compile time limit and it is intended to prevent a potential
+#     DNS service as a result of an application setting the libpng equivalent of
+#     volume level 11 (read the wikipedia article on "Up to eleven").
+#
+#     NOTE: the image of a black cat in a coal mine obviously requires this
+#     limit, but some more valid images can get very close; well over 8MByte.
+#
+#  COMPRESSION_BUFFER_LIMIT
+#     This is the (overrideable) default for the amount of memory libpng will
+#     buffer before selecting a filter for a row.  It is limited itself to
+#     COMPRESSION_BUFFER_MAX as values above that level make no change (see the
+#     previous paragraph.)
 #
 #  See png.h for more description of these options.
 option WRITE_FILTER requires WRITE
-option SELECT_FILTER_HEURISTICALLY requires WRITE_FILTER enables SET_OPTION
-option SELECT_FILTER_METHODICALLY requires WRITE_FILTER enables SET_OPTION
+option SELECT_FILTER requires WRITE_FILTER disabled
+setting COMPRESSION_BUFFER_MAX default 8453377
+setting COMPRESSION_BUFFER_LIMIT default 8453377
 
 # added at libpng-1.5.4
 

scripts/pnglibconf.h.prebuilt

@@ -1,8 +1,8 @@
-/* libpng 1.7.0beta79 STANDARD API DEFINITION */
+/* libpng 1.7.0beta80 STANDARD API DEFINITION */
 
 /* pnglibconf.h - library build configuration */
 
-/* Libpng version 1.7.0beta79, March 9, 2016 */
+/* libpng version 1.7.0beta80, May 6, 2016 */
 
 /* Copyright (c) 1998-2016 Glenn Randers-Pehrson */
 
@@ -100,8 +100,7 @@
 #define PNG_READ_tRNS_SUPPORTED
 #define PNG_READ_zTXt_SUPPORTED
 #define PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
-#define PNG_SELECT_FILTER_HEURISTICALLY_SUPPORTED
-#define PNG_SELECT_FILTER_METHODICALLY_SUPPORTED
+/*#undef PNG_SELECT_FILTER_SUPPORTED*/
 #define PNG_SEQUENTIAL_READ_SUPPORTED
 #define PNG_SETJMP_SUPPORTED
 #define PNG_SETTING_SUPPORTED
@@ -193,6 +192,8 @@
 /* settings */
 #define PNG_ABORT { (abort()); }
 #define PNG_API_RULE 0
+#define PNG_COMPRESSION_BUFFER_LIMIT 8453377
+#define PNG_COMPRESSION_BUFFER_MAX 8453377
 #define PNG_DEFAULT_GAMMA_ACCURACY 665
 #define PNG_DEFAULT_READ_MACROS 1
 #define PNG_GAMMA_THRESHOLD_FIXED 153

scripts/symbols.def

@@ -1,4 +1,4 @@
-;Version 1.7.0beta79
+;Version 1.7.0beta80
 ;--------------------------------------------------------------
 ; LIBPNG symbol list as a Win32 DEF file
 ; Contains all the symbols that can be exported from libpng