[libpng15] Added palette-index checking.

ANNOUNCE

@@ -1,5 +1,5 @@
 
-Libpng 1.5.10beta03 - February 27, 2012
+Libpng 1.5.10beta03 - March 5, 2012
 
 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.
@@ -45,9 +45,10 @@ Version 1.5.10beta01 [February 24, 2012]
 Version 1.5.10beta02 [February 27, 2012]
   Updated Makefile.in
 
-Version 1.5.10beta03 [February 27, 2012]
+Version 1.5.10beta03 [March 5, 2012]
   Removed unused "current_text" members of png_struct and the png_free()
     of png_ptr->current_text from pngread.c
+  Added palette-index checking.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net:
 (subscription required; visit

CHANGES

@@ -3830,9 +3830,10 @@ Version 1.5.10beta01 [February 24, 2012]
 Version 1.5.10beta02 [February 27, 2012]
   Updated Makefile.in
 
-Version 1.5.10beta03 [February 27, 2012]
+Version 1.5.10beta03 [March 5, 2012]
   Removed unused "current_text" members of png_struct and the png_free()
     of png_ptr->current_text from pngread.c
+  Added palette-index checking.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit

libpng-manual.txt

@@ -1,6 +1,6 @@
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.5.10beta03 - February 27, 2012
+ libpng version 1.5.10beta03 - March 5, 2012
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2011 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 1.5.10beta03 - February 27, 2012
+ libpng versions 0.97, January 1998, through 1.5.10beta03 - March 5, 2012
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2011 Glenn Randers-Pehrson
 
@@ -4142,6 +4142,15 @@ X.  Changes to Libpng from version 1.4.x to 1.5.x
 From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
 function) incorrectly returned a value of type png_uint_32.
 
+Checking for invalid palette index on read or write was added at libpng
+1.5.10.  This is enabled by default but can be disabled in each png_ptr with
+
+   png_set_check_for_invalid_index(png_ptr, allowed);
+
+      allowed  - one of
+                 0: disable
+                 1: enable
+
 A. Changes that affect users of libpng
 
 There are no substantial API changes between the non-deprecated parts of
@@ -4587,7 +4596,7 @@ Other rules can be inferred by inspecting the libpng source.
 
 XIV. Y2K Compliance in libpng
 
-February 27, 2012
+March 5, 2012
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.

libpng.3

@@ -1,4 +1,4 @@
-.TH LIBPNG 3 "February 27, 2012"
+.TH LIBPNG 3 "March 5, 2012"
 .SH NAME
 libpng \- Portable Network Graphics (PNG) Reference Library 1.5.10beta03
 .SH SYNOPSIS
@@ -552,6 +552,10 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.5.10beta03
 
 \fI\fB
 
+\fBvoid png_set_check_for_invalid_index(png_structrp \fP\fIpng_ptr\fP\fB, int \fIallowed\fP\fB);\fP
+
+\fI\fB
+
 \fBvoid png_set_cHRM (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, double \fP\fIwhite_x\fP\fB, double \fP\fIwhite_y\fP\fB, double \fP\fIred_x\fP\fB, double \fP\fIred_y\fP\fB, double \fP\fIgreen_x\fP\fB, double \fP\fIgreen_y\fP\fB, double \fP\fIblue_x\fP\fB, double \fIblue_y\fP\fB);\fP
 
 \fI\fB
@@ -977,7 +981,7 @@ 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 1.5.10beta03 - February 27, 2012
+ libpng version 1.5.10beta03 - March 5, 2012
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2011 Glenn Randers-Pehrson
@@ -988,7 +992,7 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.5.10beta03 - February 27, 2012
+ libpng versions 0.97, January 1998, through 1.5.10beta03 - March 5, 2012
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2011 Glenn Randers-Pehrson
 
@@ -5120,6 +5124,15 @@ We removed the trailing '.' from the warning and error messages.
 From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
 function) incorrectly returned a value of type png_uint_32.
 
+Checking for invalid palette index on read or write was added at libpng
+1.5.10.  This is enabled by default but can be disabled in each png_ptr with
+
+   png_set_check_for_invalid_index(png_ptr, allowed);
+
+      allowed  - one of
+                 0: disable
+                 1: enable
+
 A. Changes that affect users of libpng
 
 There are no substantial API changes between the non-deprecated parts of
@@ -5565,7 +5578,7 @@ Other rules can be inferred by inspecting the libpng source.
 
 .SH XIV. Y2K Compliance in libpng
 
-February 27, 2012
+March 5, 2012
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
@@ -5839,7 +5852,7 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.5.10beta03 - February 27, 2012:
+Libpng version 1.5.10beta03 - March 5, 2012:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -5862,7 +5875,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.5.10beta03, February 27, 2012, are
+libpng versions 1.2.6, August 15, 2004, through 1.5.10beta03, March 5, 2012, are
 Copyright (c) 2004,2006-2007 Glenn Randers-Pehrson, and are
 distributed according to the same disclaimer and license as libpng-1.2.5
 with the following individual added to the list of Contributing Authors
@@ -5961,7 +5974,7 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-February 27, 2012
+March 5, 2012
 
 .\" end of man page
 

png.c

@@ -1,8 +1,8 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * Last changed in libpng 1.5.7 [December 15, 2011]
+ * Last changed in libpng 1.5.10 [(PENDING RELEASE)]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2012 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.)
  *
@@ -655,13 +655,13 @@ png_get_copyright(png_const_structp png_ptr)
 #else
 #  ifdef __STDC__
    return PNG_STRING_NEWLINE \
-     "libpng version 1.5.10beta03 - February 27, 2012" PNG_STRING_NEWLINE \
+     "libpng version 1.5.10beta03 - March 5, 2012" PNG_STRING_NEWLINE \
      "Copyright (c) 1998-2011 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 1.5.10beta03 - February 27, 2012\
+      return "libpng version 1.5.10beta03 - March 5, 2012\
       Copyright (c) 1998-2011 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
@@ -1467,7 +1467,7 @@ static double
 png_pow10(int power)
 {
    int recip = 0;
-   double d = 1;
+   double d = 1.0;
 
    /* Handle negative exponent with a reciprocal at the end because
     * 10 is exact whereas .1 is inexact in base 2
@@ -1481,7 +1481,7 @@ png_pow10(int power)
    if (power > 0)
    {
       /* Decompose power bitwise. */
-      double mult = 10;
+      double mult = 10.0;
       do
       {
          if (power & 1) d *= mult;
@@ -1600,7 +1600,8 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
             {
                double d;
 
-               fp *= 10;
+               fp *= 10.0;
+
                /* Use modf here, not floor and subtract, so that
                 * the separation is done in one step.  At the end
                 * of the loop don't break the number into parts so
@@ -1613,7 +1614,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
                {
                   d = floor(fp + .5);
 
-                  if (d > 9)
+                  if (d > 9.0)
                   {
                      /* Rounding up to 10, handle that here. */
                      if (czero > 0)
@@ -1621,9 +1622,10 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
                         --czero, d = 1;
                         if (cdigits == 0) --clead;
                      }
+
                      else
                      {
-                        while (cdigits > 0 && d > 9)
+                        while (cdigits > 0 && d > 9.0)
                         {
                            int ch = *--ascii;
 
@@ -1648,7 +1650,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
                          * exponent but take into account the leading
                          * decimal point.
                          */
-                        if (d > 9)  /* cdigits == 0 */
+                        if (d > 9.0)  /* cdigits == 0 */
                         {
                            if (exp_b10 == (-1))
                            {
@@ -1669,18 +1671,19 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
                               ++exp_b10;
 
                            /* In all cases we output a '1' */
-                           d = 1;
+                           d = 1.0;
                         }
                      }
                   }
                   fp = 0; /* Guarantees termination below. */
                }
 
-               if (d == 0)
+               if (d == 0.0)
                {
                   ++czero;
                   if (cdigits == 0) ++clead;
                }
+
                else
                {
                   /* Included embedded zeros in the digit count. */
@@ -1708,6 +1711,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
                                                                  above */
                      --exp_b10;
                   }
+
                   *ascii++ = (char)(48 + (int)d), ++cdigits;
                }
             }

png.h

@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.5.10beta03 - February 27, 2012
+ * libpng version 1.5.10beta03 - March 5, 2012
  * Copyright (c) 1998-2012 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.)
@@ -11,7 +11,7 @@
  * Authors and maintainers:
  *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
  *   libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
- *   libpng versions 0.97, January 1998, through 1.5.10beta03 - February 27, 2012: Glenn
+ *   libpng versions 0.97, January 1998, through 1.5.10beta03 - March 5, 2012: Glenn
  *   See also "Contributing Authors", below.
  *
  * Note about libpng version numbers:
@@ -204,7 +204,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.2.6, August 15, 2004, through 1.5.10beta03, February 27, 2012, are
+ * libpng versions 1.2.6, August 15, 2004, through 1.5.10beta03, March 5, 2012, are
  * Copyright (c) 2004, 2006-2012 Glenn Randers-Pehrson, and are
  * distributed according to the same disclaimer and license as libpng-1.2.5
  * with the following individual added to the list of Contributing Authors:
@@ -316,7 +316,7 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    February 27, 2012
+ *    March 5, 2012
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
@@ -382,7 +382,7 @@
 /* Version information for png.h - this should match the version in png.c */
 #define PNG_LIBPNG_VER_STRING "1.5.10beta03"
 #define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.5.10beta03 - February 27, 2012\n"
+     " libpng version 1.5.10beta03 - March 5, 2012\n"
 
 #define PNG_LIBPNG_VER_SONUM   15
 #define PNG_LIBPNG_VER_DLLNUM  15
@@ -2638,6 +2638,12 @@ PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
       : (png_int_32)png_get_uint_32(buf)))
 #endif
 
+#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
+    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
+PNG_EXPORT(234, void, png_set_check_for_invalid_index, (png_structp png_ptr,
+    int allowed));
+#endif
+
 /* Maintainer: Put new public prototypes here ^, in libpng.3, and project
  * defs
  */
@@ -2647,7 +2653,7 @@ PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
  * scripts/symbols.def as well.
  */
 #ifdef PNG_EXPORT_LAST_ORDINAL
-  PNG_EXPORT_LAST_ORDINAL(233);
+  PNG_EXPORT_LAST_ORDINAL(234);
 #endif
 
 #ifdef __cplusplus

pngpriv.h

@@ -2,11 +2,11 @@
 /* pngpriv.h - private declarations for use inside libpng
  *
  * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2012 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.)
  *
- * Last changed in libpng 1.5.7 [December 15, 2011]
+ * Last changed in libpng 1.5.10 [(PENDING RELEASE)]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -1395,6 +1395,13 @@ PNG_EXTERN void png_check_IHDR PNGARG((png_structp png_ptr,
     int color_type, int interlace_type, int compression_type,
     int filter_type));
 
+/* Added at libpng version 1.5.10 */
+#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
+    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
+PNG_EXTERN void png_do_check_palette_indexes PNGARG((png_structp png_ptr,
+    png_row_infop row_info));
+#endif
+
 /* Free all memory used by the read (old method - NOT DLL EXPORTED) */
 PNG_EXTERN void png_read_destroy PNGARG((png_structp png_ptr,
     png_infop info_ptr, png_infop end_info_ptr));

pngread.c

@@ -801,6 +801,13 @@ png_read_end(png_structp png_ptr, png_infop info_ptr)
 
    png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
 
+#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
+   /* Report invalid palette index; added at libng-1.5.10 */
+   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+      png_ptr->num_palette_max > png_ptr->num_palette)
+     png_warning(png_ptr, "Read palette index exceeding num_palette");
+#endif
+
    do
    {
       png_uint_32 length = png_read_chunk_header(png_ptr);

pngrtran.c

@@ -1,8 +1,8 @@
 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * Last changed in libpng 1.5.7 [December 15, 2011]
+ * Last changed in libpng 1.5.10 [(PENDING RELEASE)]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2012 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.)
  *
@@ -2296,6 +2296,12 @@ png_do_read_transformations(png_structp png_ptr, png_row_infop row_info)
       png_do_unpack(row_info, png_ptr->row_buf + 1);
 #endif
 
+#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
+   /* Added at libpng-1.5.10 */
+   if (row_info->color_type == PNG_COLOR_TYPE_PALETTE)
+      png_do_check_palette_indexes(png_ptr, row_info);
+#endif
+
 #ifdef PNG_READ_BGR_SUPPORTED
    if (png_ptr->transformations & PNG_BGR)
       png_do_bgr(row_info, png_ptr->row_buf + 1);

pngset.c

@@ -1,8 +1,8 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * Last changed in libpng 1.5.7 [December 15, 2011]
+ * Last changed in libpng 1.5.10 [(PENDING RELEASE)]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2012 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.)
  *
@@ -1281,4 +1281,20 @@ png_set_benign_errors(png_structp png_ptr, int allowed)
       png_ptr->flags &= ~PNG_FLAG_BENIGN_ERRORS_WARN;
 }
 #endif /* PNG_BENIGN_ERRORS_SUPPORTED */
+
+#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
+   /* Do not report invalid palette index; added at libng-1.5.10 */
+void PNGAPI
+png_set_check_for_invalid_index(png_structp png_ptr, int allowed)
+{
+   png_debug(1, "in png_set_check_for_invalid_index");
+
+   if (allowed)
+      png_ptr->num_palette_max = 0;
+
+   else
+      png_ptr->num_palette_max = -1;
+}
+#endif
+
 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */

pngtrans.c

@@ -1,8 +1,8 @@
 
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
- * Last changed in libpng 1.5.4 [July 7, 2011]
+ * Last changed in libpng 1.5.10 [(PENDING RELEASE)]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2012 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.)
  *
@@ -619,6 +619,109 @@ png_do_bgr(png_row_infop row_info, png_bytep row)
 }
 #endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
 
+#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
+    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
+/* Added at libpng-1.5.10 */
+void /* PRIVATE */
+png_do_check_palette_indexes(png_structp png_ptr, png_row_infop row_info)
+{
+   if (png_ptr->num_palette < (1 << row_info->bit_depth) &&
+      png_ptr->num_palette_max >= 0)
+   {
+      /* Calculations moved outside switch in an attempt to stop different
+       * compiler warnings.  'padding' is in *bits* within the last byte, it is
+       * an 'int' because pixel_depth becomes an 'int' in the expression below,
+       * and this calculation is used because it avoids warnings that other
+       * forms produced on either GCC or MSVC.
+       */
+      int padding = (-row_info->pixel_depth * row_info->width) & 7;
+      png_bytep rp = png_ptr->row_buf + 1 + row_info->rowbytes;
+
+      switch (row_info->bit_depth)
+      {
+         case 1:
+         {
+            /* in this case, all bytes must be 0 so we don't need
+             * to unpack the pixels except for the rightmost one.
+             */
+            for (; rp > png_ptr->row_buf; rp--)
+            {
+              if (*rp >> padding != 0)
+                 png_ptr->num_palette_max = 1;
+              padding = 0;
+            }
+
+            break;
+         }
+
+         case 2:
+         {
+            for (; rp > png_ptr->row_buf; rp--)
+            {
+              int i = ((*rp >> padding) & 0x03);
+
+              if (i > png_ptr->num_palette_max)
+                 png_ptr->num_palette_max = i;
+
+              i = (((*rp >> padding) >> 2) & 0x03);
+
+              if (i > png_ptr->num_palette_max)
+                 png_ptr->num_palette_max = i;
+
+              i = (((*rp >> padding) >> 4) & 0x03);
+
+              if (i > png_ptr->num_palette_max)
+                 png_ptr->num_palette_max = i;
+
+              i = (((*rp >> padding) >> 6) & 0x03);
+
+              if (i > png_ptr->num_palette_max)
+                 png_ptr->num_palette_max = i;
+
+              padding = 0;
+            }
+
+            break;
+         }
+
+         case 4:
+         {
+            for (; rp > png_ptr->row_buf; rp--)
+            {
+              int i = ((*rp >> padding) & 0x0f);
+
+              if (i > png_ptr->num_palette_max)
+                 png_ptr->num_palette_max = i;
+
+              i = (((*rp >> padding) >> 4) & 0x0f);
+
+              if (i > png_ptr->num_palette_max)
+                 png_ptr->num_palette_max = i;
+
+              padding = 0;
+            }
+
+            break;
+         }
+
+         case 8:
+         {
+            for (; rp > png_ptr->row_buf; rp--)
+            {
+               if (*rp >= png_ptr->num_palette_max)
+                  png_ptr->num_palette_max = (int) *rp;
+            }
+
+            break;
+         }
+
+         default:
+            break;
+      }
+   }
+}
+#endif /* PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED */
+
 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
     defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
 #ifdef PNG_USER_TRANSFORM_PTR_SUPPORTED

pngwrite.c

@@ -1,8 +1,8 @@
 
 /* pngwrite.c - general routines to write a PNG file
  *
- * Last changed in libpng 1.5.7 [December 15, 2011]
+ * Last changed in libpng 1.5.10 [(PENDING RELEASE)]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2012 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.)
  *
@@ -305,6 +305,11 @@ png_write_end(png_structp png_ptr, png_infop info_ptr)
    if (!(png_ptr->mode & PNG_HAVE_IDAT))
       png_error(png_ptr, "No IDATs written into file");
 
+#ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
+   if (png_ptr->num_palette_max > png_ptr->num_palette)
+      png_warning(png_ptr, "Wrote palette index exceeding num_palette");
+#endif
+
    /* See if user wants us to write information chunks */
    if (info_ptr != NULL)
    {
@@ -798,6 +803,13 @@ png_write_row(png_structp png_ptr, png_const_bytep row)
    }
 #endif
 
+/* Added at libpng-1.5.10 */
+#ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
+   /* Check for out-of-range palette index */
+   if(row_info.color_type == PNG_COLOR_TYPE_PALETTE)
+      png_do_check_palette_indexes(png_ptr, &row_info);
+#endif
+
    /* Find a filter if necessary, filter the row and write it out. */
    png_write_find_filter(png_ptr, &row_info);
 

scripts/pnglibconf.dfa

@@ -578,3 +578,13 @@ option WRITE_COMPRESSED_TEXT enables WRITE_TEXT
 # leave the row_pointers member out of the info structure.
 
 option INFO_IMAGE
+
+# added at libpng-1.5.10
+# Turn this off to disable warning about invalid palette index and
+# leave the num_palette_max member out of the png structure.
+
+option CHECK_FOR_INVALID_INDEX enables READ_CHECK_FOR_INVALID_INDEX
+option CHECK_FOR_INVALID_INDEX enables WRITE_CHECK_FOR_INVALID_INDEX
+option READ_CHECK_FOR_INVALID_INDEX requires READ CHECK_FOR_INVALID_INDEX
+option WRITE_CHECK_FOR_INVALID_INDEX requires WRITE CHECK_FOR_INVALID_INDEX
+

scripts/pnglibconf.h.prebuilt

@@ -3,9 +3,9 @@
 
 /* pnglibconf.h - library build configuration */
 
-/* Libpng 1.5.10beta03 - February 27, 2012 */
+/* Libpng 1.5.10beta03 - March 5, 2012 */
 
-/* Copyright (c) 1998-2011 Glenn Randers-Pehrson */
+/* Copyright (c) 1998-2012 Glenn Randers-Pehrson */
 
 /* This code is released under the libpng license. */
 /* For conditions of distribution and use, see the disclaimer */
@@ -41,6 +41,7 @@
 #define PNG_bKGD_SUPPORTED
 #define PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
 #define PNG_CHECK_cHRM_SUPPORTED
+#define PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
 #define PNG_cHRM_SUPPORTED
 #define PNG_CONSOLE_IO_SUPPORTED
 #define PNG_CONVERT_tIME_SUPPORTED
@@ -70,6 +71,7 @@
 #define PNG_READ_BACKGROUND_SUPPORTED
 #define PNG_READ_BGR_SUPPORTED
 #define PNG_READ_bKGD_SUPPORTED
+#define PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
 #define PNG_READ_cHRM_SUPPORTED
 #define PNG_READ_COMPOSITE_NODIV_SUPPORTED
 #define PNG_READ_COMPRESSED_TEXT_SUPPORTED
@@ -141,6 +143,7 @@
 #define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
 #define PNG_WRITE_BGR_SUPPORTED
 #define PNG_WRITE_bKGD_SUPPORTED
+#define PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
 #define PNG_WRITE_cHRM_SUPPORTED
 #define PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
 #define PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED

scripts/symbols.def

@@ -239,3 +239,4 @@ EXPORTS
  png_get_cHRM_XYZ_fixed @231
  png_set_cHRM_XYZ @232
  png_set_cHRM_XYZ_fixed @233
+ png_set_check_for_invalid_index @234