git-svn-id: https://mpc-hc.svn.sourceforge.net/svnroot/mpc-hc/trunk@148 10f7b99b-c216-0410-bff0-8a66a9350fd8

12 files changed, 136 insertions, 99 deletions

diff --git a/src/libpng/png.c b/src/libpng/png.c
index f8d6950c4..9665c2c1c 100644
--- a/src/libpng/png.c
+++ b/src/libpng/png.c
@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * Last changed in libpng 1.2.15 January 5, 2007
+ * Last changed in libpng 1.2.17 May 15, 2007
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2007 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -13,7 +13,7 @@
 #include "png.h"
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef version_1_2_16 Your_png_h_is_not_version_1_2_16;
+typedef version_1_2_18 Your_png_h_is_not_version_1_2_18;
 
 /* Version information for C files.  This had better match the version
  * string defined in png.h.  */
@@ -68,7 +68,7 @@ const int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
 const int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
 
 /* width of interlace block (used in assembler routines only) */
-#ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
+#ifdef PNG_HAVE_MMX_COMBINE_ROW
 const int FARDATA png_pass_width[] = {8, 4, 4, 2, 2, 1, 1};
 #endif
 
@@ -490,6 +490,11 @@ if (mask & PNG_FREE_SPLT)
 #endif
 
 #if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+  if(png_ptr->unknown_chunk.data)
+  {
+    png_free(png_ptr, png_ptr->unknown_chunk.data);
+    png_ptr->unknown_chunk.data = NULL;
+  }
 #ifdef PNG_FREE_ME_SUPPORTED
 if ((mask & PNG_FREE_UNKN) & info_ptr->free_me)
 #else
@@ -701,7 +706,7 @@ png_charp PNGAPI
 png_get_copyright(png_structp png_ptr)
 {
    if (&png_ptr != NULL)  /* silence compiler warning about unused png_ptr */
-   return ((png_charp) "\n libpng version 1.2.16 - January 31, 2007\n\
+   return ((png_charp) "\n libpng version 1.2.18 - May 15, 2007\n\
    Copyright (c) 1998-2007 Glenn Randers-Pehrson\n\
    Copyright (c) 1996-1997 Andreas Dilger\n\
    Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.\n");
@@ -796,13 +801,13 @@ png_init_mmx_flags (png_structp png_ptr)
 
     if (png_mmx_support() > 0) {
         png_ptr->asm_flags |= PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU
-#    ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
+#    ifdef PNG_HAVE_MMX_COMBINE_ROW
                               | PNG_ASM_FLAG_MMX_READ_COMBINE_ROW
 #    endif
-#    ifdef PNG_HAVE_ASSEMBLER_READ_INTERLACE
+#    ifdef PNG_HAVE_MMX_READ_INTERLACE
                               | PNG_ASM_FLAG_MMX_READ_INTERLACE
 #    endif
-#    ifndef PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+#    ifndef PNG_HAVE_MMX_READ_FILTER_ROW
                               ;
 #    else
                               | PNG_ASM_FLAG_MMX_READ_FILTER_SUB
diff --git a/src/libpng/png.h b/src/libpng/png.h
index 1793e9df7..1c4f56fad 100644
--- a/src/libpng/png.h
+++ b/src/libpng/png.h
@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.2.16 - January 31, 2007
+ * libpng version 1.2.18 - May 15, 2007
  * Copyright (c) 1998-2007 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.)
@@ -9,7 +9,7 @@
  * 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 1.2.16 - January 31, 2007: Glenn
+ *  libpng versions 0.97, January 1998, through 1.2.18 - May 15, 2007: Glenn
  *  See also "Contributing Authors", below.
  *
  * Note about libpng version numbers:
@@ -143,6 +143,13 @@
  *    1.2.16rc1               13    10216  12.so.0.16[.0]
  *    1.0.24                  10    10024  10.so.0.24[.0]
  *    1.2.16                  13    10216  12.so.0.16[.0]
+ *    1.2.17beta1-2           13    10217  12.so.0.17[.0]
+ *    1.0.25rc1               10    10025  10.so.0.25[.0]
+ *    1.2.17rc1-3             13    10217  12.so.0.17[.0]
+ *    1.0.25                  10    10025  10.so.0.25[.0]
+ *    1.2.17                  13    10217  12.so.0.17[.0]
+ *    1.0.26                  10    10026  10.so.0.26[.0]
+ *    1.2.18                  13    10218  12.so.0.18[.0]
  *
  *    Henceforth the source version will match the shared-library major
  *    and minor numbers; the shared-library major version number will be
@@ -172,8 +179,8 @@
  * If you modify libpng you may insert additional notices immediately following
  * this sentence.
  *
- * libpng versions 1.2.6, August 15, 2004, through 1.2.16, January 31, 2007, are
- * Copyright (c) 2004, 2007 Glenn Randers-Pehrson, and are
+ * libpng versions 1.2.6, August 15, 2004, through 1.2.18, May 15, 2007, 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:
  *
@@ -284,13 +291,13 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    January 31, 2007
+ *    May 15, 2007
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
  *
  *    This is your unofficial assurance that libpng from version 0.71 and
- *    upward through 1.2.16 are Y2K compliant.  It is my belief that earlier
+ *    upward through 1.2.18 are Y2K compliant.  It is my belief that earlier
  *    versions were also Y2K compliant.
  *
  *    Libpng only has three year fields.  One is a 2-byte unsigned integer
@@ -346,9 +353,9 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.2.16"
+#define PNG_LIBPNG_VER_STRING "1.2.18"
 #define PNG_HEADER_VERSION_STRING \
-   " libpng version 1.2.16 - January 31, 2007 (header)\n"
+   " libpng version 1.2.18 - May 15, 2007 (header)\n"
 
 #define PNG_LIBPNG_VER_SONUM   0
 #define PNG_LIBPNG_VER_DLLNUM  13
@@ -356,7 +363,7 @@
 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
 #define PNG_LIBPNG_VER_MAJOR   1
 #define PNG_LIBPNG_VER_MINOR   2
-#define PNG_LIBPNG_VER_RELEASE 16
+#define PNG_LIBPNG_VER_RELEASE 18
 /* This should match the numeric part of the final component of
  * PNG_LIBPNG_VER_STRING, omitting any leading zero: */
 
@@ -384,7 +391,7 @@
  * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
  * version 1.0.0 was mis-numbered 100 instead of 10000).  From
  * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=release */
-#define PNG_LIBPNG_VER 10216 /* 1.2.16 */
+#define PNG_LIBPNG_VER 10218 /* 1.2.18 */
 
 #ifndef PNG_VERSION_INFO_ONLY
 /* include the compression library's header */
@@ -1388,13 +1395,18 @@ struct png_struct_def
    png_uint_32 user_height_max;
 #endif
 
+/* New member added in libpng-1.0.25 and 1.2.17 */
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+   /* storage for unknown chunk that the library doesn't recognize. */
+   png_unknown_chunk unknown_chunk;
+#endif
 };
 
 
 /* This triggers a compiler error in png.c, if png.c and png.h
  * do not agree upon the version number.
  */
-typedef png_structp version_1_2_16;
+typedef png_structp version_1_2_18;
 
 typedef png_struct FAR * FAR * png_structpp;
 
@@ -2390,7 +2402,7 @@ extern PNG_EXPORT(void,png_set_sCAL_s) PNGARG((png_structp png_ptr,
    handling or default unknown chunk handling is not desired.  Any chunks not
    listed will be handled in the default manner.  The IHDR and IEND chunks
    must not be listed.
-      keep = 0: follow default behavour
+      keep = 0: follow default behaviour
            = 1: do not keep
            = 2: keep only if safe-to-copy
            = 3: keep even if unsafe-to-copy
@@ -2671,16 +2683,21 @@ extern PNG_EXPORT(void,png_save_uint_16)
  * be found in the files where the functions are located.
  */
 
-#if defined(PNG_INTERNAL)
 
-/* Various modes of operation.  Note that after an init, mode is set to
- * zero automatically when the structure is created.
+/* Various modes of operation, that are visible to applications because
+ * they are used for unknown chunk location.
  */
 #define PNG_HAVE_IHDR               0x01
 #define PNG_HAVE_PLTE               0x02
 #define PNG_HAVE_IDAT               0x04
 #define PNG_AFTER_IDAT              0x08 /* Have complete zlib datastream */
 #define PNG_HAVE_IEND               0x10
+
+#if defined(PNG_INTERNAL)
+
+/* More modes of operation.  Note that after an init, mode is set to
+ * zero automatically when the structure is created.
+ */
 #define PNG_HAVE_gAMA               0x20
 #define PNG_HAVE_cHRM               0x40
 #define PNG_HAVE_sRGB               0x80
diff --git a/src/libpng/pngconf.h b/src/libpng/pngconf.h
index d71a15329..a5047325f 100644
--- a/src/libpng/pngconf.h
+++ b/src/libpng/pngconf.h
@@ -1,7 +1,7 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.2.16 - January 31, 2007
+ * libpng version 1.2.18 - May 15, 2007
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2007 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -1458,9 +1458,9 @@ typedef z_stream FAR *  png_zstreamp;
  * MMX will be detected at run time and used if present.
  */
 #ifdef PNG_USE_PNGVCRD
-#  define PNG_HAVE_ASSEMBLER_COMBINE_ROW
-#  define PNG_HAVE_ASSEMBLER_READ_INTERLACE
-#  define PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+#  define PNG_HAVE_MMX_COMBINE_ROW
+#  define PNG_HAVE_MMX_READ_INTERLACE
+#  define PNG_HAVE_MMX_READ_FILTER_ROW
 #endif
 
 /* Set this in the makefile for gcc/as on Pentium, not here. */
@@ -1468,9 +1468,9 @@ typedef z_stream FAR *  png_zstreamp;
  * MMX will be detected at run time and used if present.
  */
 #ifdef PNG_USE_PNGGCCRD
-#  define PNG_HAVE_ASSEMBLER_COMBINE_ROW
-#  define PNG_HAVE_ASSEMBLER_READ_INTERLACE
-#  define PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+#  define PNG_HAVE_MMX_COMBINE_ROW
+#  define PNG_HAVE_MMX_READ_INTERLACE
+#  define PNG_HAVE_MMX_READ_FILTER_ROW
 #endif
 /* - see pnggccrd.c for info about what is currently enabled */
 
diff --git a/src/libpng/pngerror.c b/src/libpng/pngerror.c
index c8c58b91d..f50f65344 100644
--- a/src/libpng/pngerror.c
+++ b/src/libpng/pngerror.c
@@ -113,7 +113,7 @@ png_warning(png_structp png_ptr, png_const_charp warning_message)
  * if the character is invalid.
  */
 #define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97))
-static PNG_CONST char png_digit[16] = {
+const static PNG_CONST char png_digit[16] = {
    '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
    'A', 'B', 'C', 'D', 'E', 'F'
 };
diff --git a/src/libpng/pnggccrd.c b/src/libpng/pnggccrd.c
index 7983f8ea1..fab523c0b 100644
--- a/src/libpng/pnggccrd.c
+++ b/src/libpng/pnggccrd.c
@@ -250,9 +250,9 @@
 int PNGAPI png_mmx_support(void);
 
 #ifdef PNG_USE_LOCAL_ARRAYS
-static const int FARDATA png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
-static const int FARDATA png_pass_inc[7]   = {8, 8, 4, 4, 2, 2, 1};
-static const int FARDATA png_pass_width[7] = {8, 4, 4, 2, 2, 1, 1};
+const static int FARDATA png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+const static int FARDATA png_pass_inc[7]   = {8, 8, 4, 4, 2, 2, 1};
+const static int FARDATA png_pass_width[7] = {8, 4, 4, 2, 2, 1, 1};
 #endif
 
 #if defined(PNG_MMX_CODE_SUPPORTED)
@@ -311,30 +311,30 @@ static const int FARDATA png_pass_width[7] = {8, 4, 4, 2, 2, 1, 1};
 static int _unmask;
 #endif
 
-static unsigned long long _mask8_0  = 0x0102040810204080LL;
+const static unsigned long long _mask8_0  = 0x0102040810204080LL;
 
-static unsigned long long _mask16_1 = 0x0101020204040808LL;
-static unsigned long long _mask16_0 = 0x1010202040408080LL;
+const static unsigned long long _mask16_1 = 0x0101020204040808LL;
+const static unsigned long long _mask16_0 = 0x1010202040408080LL;
 
-static unsigned long long _mask24_2 = 0x0101010202020404LL;
-static unsigned long long _mask24_1 = 0x0408080810101020LL;
-static unsigned long long _mask24_0 = 0x2020404040808080LL;
+const static unsigned long long _mask24_2 = 0x0101010202020404LL;
+const static unsigned long long _mask24_1 = 0x0408080810101020LL;
+const static unsigned long long _mask24_0 = 0x2020404040808080LL;
 
-static unsigned long long _mask32_3 = 0x0101010102020202LL;
-static unsigned long long _mask32_2 = 0x0404040408080808LL;
-static unsigned long long _mask32_1 = 0x1010101020202020LL;
-static unsigned long long _mask32_0 = 0x4040404080808080LL;
+const static unsigned long long _mask32_3 = 0x0101010102020202LL;
+const static unsigned long long _mask32_2 = 0x0404040408080808LL;
+const static unsigned long long _mask32_1 = 0x1010101020202020LL;
+const static unsigned long long _mask32_0 = 0x4040404080808080LL;
 
-static unsigned long long _mask48_5 = 0x0101010101010202LL;
-static unsigned long long _mask48_4 = 0x0202020204040404LL;
-static unsigned long long _mask48_3 = 0x0404080808080808LL;
-static unsigned long long _mask48_2 = 0x1010101010102020LL;
-static unsigned long long _mask48_1 = 0x2020202040404040LL;
-static unsigned long long _mask48_0 = 0x4040808080808080LL;
+const static unsigned long long _mask48_5 = 0x0101010101010202LL;
+const static unsigned long long _mask48_4 = 0x0202020204040404LL;
+const static unsigned long long _mask48_3 = 0x0404080808080808LL;
+const static unsigned long long _mask48_2 = 0x1010101010102020LL;
+const static unsigned long long _mask48_1 = 0x2020202040404040LL;
+const static unsigned long long _mask48_0 = 0x4040808080808080LL;
 
-static unsigned long long _const4   = 0x0000000000FFFFFFLL;
-//static unsigned long long _const5 = 0x000000FFFFFF0000LL;     // NOT USED
-static unsigned long long _const6   = 0x00000000000000FFLL;
+const static unsigned long long _const4   = 0x0000000000FFFFFFLL;
+//const static unsigned long long _const5 = 0x000000FFFFFF0000LL;     // NOT USED
+const static unsigned long long _const6   = 0x00000000000000FFLL;
 
 // These are used in the row-filter routines and should/would be local
 //  variables if not for gcc addressing limitations.
diff --git a/src/libpng/pngpread.c b/src/libpng/pngpread.c
index d226c75d3..1470b0fe0 100644
--- a/src/libpng/pngpread.c
+++ b/src/libpng/pngpread.c
@@ -1,9 +1,9 @@
 
 /* pngpread.c - read a png file in push mode
  *
- * Last changed in libpng 1.2.13 November 13, 2006
+ * Last changed in libpng 1.2.17 May 15, 2007
  * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2006 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2007 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.)
  */
@@ -1488,8 +1488,6 @@ png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32
 #if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
    if (png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
    {
-       png_unknown_chunk chunk;
-
 #ifdef PNG_MAX_MALLOC_64K
        if (length > (png_uint_32)65535L)
        {
@@ -1498,28 +1496,35 @@ png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32
            length = (png_uint_32)65535L;
        }
 #endif
-
-       png_strcpy((png_charp)chunk.name, (png_charp)png_ptr->chunk_name);
-       chunk.data = (png_bytep)png_malloc(png_ptr, length);
-       png_crc_read(png_ptr, chunk.data, length);
-       chunk.size = length;
+       png_strcpy((png_charp)png_ptr->unknown_chunk.name,
+         (png_charp)png_ptr->chunk_name);
+       png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length);
+       png_ptr->unknown_chunk.size = (png_size_t)length;
+       png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length);
 #if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
        if(png_ptr->read_user_chunk_fn != NULL)
        {
           /* callback to user unknown chunk handler */
-          if ((*(png_ptr->read_user_chunk_fn)) (png_ptr, &chunk) <= 0)
+          int ret;
+          ret = (*(png_ptr->read_user_chunk_fn))
+            (png_ptr, &png_ptr->unknown_chunk);
+          if (ret < 0)
+             png_chunk_error(png_ptr, "error in user chunk");
+          if (ret == 0)
           {
              if (!(png_ptr->chunk_name[0] & 0x20))
                 if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
                      PNG_HANDLE_CHUNK_ALWAYS)
                    png_chunk_error(png_ptr, "unknown critical chunk");
+                png_set_unknown_chunks(png_ptr, info_ptr,
+                   &png_ptr->unknown_chunk, 1);
           }
-             png_set_unknown_chunks(png_ptr, info_ptr, &chunk, 1);
        }
-       else
+#else
+       png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
 #endif
-          png_set_unknown_chunks(png_ptr, info_ptr, &chunk, 1);
-       png_free(png_ptr, chunk.data);
+       png_free(png_ptr, png_ptr->unknown_chunk.data);
+       png_ptr->unknown_chunk.data = NULL;
    }
    else
 #endif
@@ -1553,11 +1558,11 @@ void PNGAPI
 png_progressive_combine_row (png_structp png_ptr,
    png_bytep old_row, png_bytep new_row)
 {
-   if(png_ptr == NULL) return;
 #ifdef PNG_USE_LOCAL_ARRAYS
    const int FARDATA png_pass_dsp_mask[7] =
       {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
 #endif
+   if(png_ptr == NULL) return;
    if (new_row != NULL)    /* new_row must == png_ptr->row_buf here. */
       png_combine_row(png_ptr, old_row, png_pass_dsp_mask[png_ptr->pass]);
 }
diff --git a/src/libpng/pngrtran.c b/src/libpng/pngrtran.c
index 2fa96f312..6ef0a1c07 100644
--- a/src/libpng/pngrtran.c
+++ b/src/libpng/pngrtran.c
@@ -583,7 +583,7 @@ png_set_expand_gray_1_2_4_to_8(png_structp png_ptr)
 {
    png_debug(1, "in png_set_expand_gray_1_2_4_to_8\n");
    if(png_ptr == NULL) return;
-   png_ptr->transformations |= PNG_EXPAND_tRNS;
+   png_ptr->transformations |= PNG_EXPAND;
 }
 #endif
 
@@ -1293,9 +1293,9 @@ png_do_read_transformations(png_structp png_ptr)
       if(rgb_error)
       {
          png_ptr->rgb_to_gray_status=1;
-         if(png_ptr->transformations == PNG_RGB_TO_GRAY_WARN)
+         if(png_ptr->transformations & PNG_RGB_TO_GRAY_WARN)
             png_warning(png_ptr, "png_do_rgb_to_gray found nongray pixel");
-         if(png_ptr->transformations == PNG_RGB_TO_GRAY_ERR)
+         if(png_ptr->transformations & PNG_RGB_TO_GRAY_ERR)
             png_error(png_ptr, "png_do_rgb_to_gray found nongray pixel");
       }
    }
@@ -3965,7 +3965,7 @@ png_do_dither(png_row_infop row_info, png_bytep row,
 
 #ifdef PNG_FLOATING_POINT_SUPPORTED
 #if defined(PNG_READ_GAMMA_SUPPORTED)
-static int png_gamma_shift[] =
+const static int png_gamma_shift[] =
    {0x10, 0x21, 0x42, 0x84, 0x110, 0x248, 0x550, 0xff0, 0x00};
 
 /* We build the 8- or 16-bit gamma tables here.  Note that for 16-bit
diff --git a/src/libpng/pngrutil.c b/src/libpng/pngrutil.c
index 6157b3de4..2abca7cc5 100644
--- a/src/libpng/pngrutil.c
+++ b/src/libpng/pngrutil.c
@@ -1,7 +1,7 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * Last changed in libpng 1.2.15 January 5, 2007
+ * Last changed in libpng 1.2.17 May 15, 2007
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2007 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -181,7 +181,7 @@ png_decompress_chunk(png_structp png_ptr, int comp_type,
                               png_charp chunkdata, png_size_t chunklength,
                               png_size_t prefix_size, png_size_t *newlength)
 {
-   static char msg[] = "Error decoding compressed text";
+   const static char msg[] = "Error decoding compressed text";
    png_charp text;
    png_size_t text_size;
 
@@ -1314,7 +1314,10 @@ png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    }
 
    if (png_crc_finish(png_ptr, 0))
+   {
+      png_ptr->num_trans = 0;
       return;
+   }
 
    png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans,
       &(png_ptr->trans_values));
@@ -2173,8 +2176,6 @@ png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    if ((png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS) ||
        (png_ptr->read_user_chunk_fn != NULL))
    {
-       png_unknown_chunk chunk;
-
 #ifdef PNG_MAX_MALLOC_64K
        if (length > (png_uint_32)65535L)
        {
@@ -2183,30 +2184,35 @@ png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
            length = (png_uint_32)65535L;
        }
 #endif
-       png_strcpy((png_charp)chunk.name, (png_charp)png_ptr->chunk_name);
-       chunk.data = (png_bytep)png_malloc(png_ptr, length);
-       chunk.size = (png_size_t)length;
-       png_crc_read(png_ptr, (png_bytep)chunk.data, length);
+       png_strcpy((png_charp)png_ptr->unknown_chunk.name,
+         (png_charp)png_ptr->chunk_name);
+       png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length);
+       png_ptr->unknown_chunk.size = (png_size_t)length;
+       png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length);
 #if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
        if(png_ptr->read_user_chunk_fn != NULL)
        {
           /* callback to user unknown chunk handler */
-          if ((*(png_ptr->read_user_chunk_fn)) (png_ptr, &chunk) <= 0)
+          int ret;
+          ret = (*(png_ptr->read_user_chunk_fn))
+            (png_ptr, &png_ptr->unknown_chunk);
+          if (ret < 0)
+             png_chunk_error(png_ptr, "error in user chunk");
+          if (ret == 0)
           {
              if (!(png_ptr->chunk_name[0] & 0x20))
                 if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
                      PNG_HANDLE_CHUNK_ALWAYS)
-                 {
-                   png_free(png_ptr, chunk.data);
                    png_chunk_error(png_ptr, "unknown critical chunk");
-                 }
-             png_set_unknown_chunks(png_ptr, info_ptr, &chunk, 1);
+             png_set_unknown_chunks(png_ptr, info_ptr,
+               &png_ptr->unknown_chunk, 1);
           }
        }
-       else
+#else
+       png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
 #endif
-          png_set_unknown_chunks(png_ptr, info_ptr, &chunk, 1);
-       png_free(png_ptr, chunk.data);
+       png_free(png_ptr, png_ptr->unknown_chunk.data);
+       png_ptr->unknown_chunk.data = NULL;
    }
    else
 #endif
diff --git a/src/libpng/pngset.c b/src/libpng/pngset.c
index 24fa24dea..f1a1ef610 100644
--- a/src/libpng/pngset.c
+++ b/src/libpng/pngset.c
@@ -1,7 +1,7 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * Last changed in libpng 1.2.15 January 5, 2007
+ * Last changed in libpng 1.2.17 May 15, 2007
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2007 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -877,7 +877,9 @@ png_set_text_2(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
          textp->itxt_length = 0;
 #endif
       }
+#if 0 /* appears to be redundant; */
       info_ptr->text[info_ptr->num_text]= *textp;
+#endif
       info_ptr->num_text++;
       png_debug1(3, "transferred text chunk %d\n", info_ptr->num_text);
    }
@@ -1200,13 +1202,13 @@ png_set_asm_flags (png_structp png_ptr, png_uint_32 asm_flags)
 #ifdef PNG_MMX_CODE_SUPPORTED
 
     settable_mmx_flags =
-#ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
+#ifdef PNG_HAVE_MMX_COMBINE_ROW
                          PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  |
 #endif
-#ifdef PNG_HAVE_ASSEMBLER_READ_INTERLACE
+#ifdef PNG_HAVE_MMX_READ_INTERLACE
                          PNG_ASM_FLAG_MMX_READ_INTERLACE    |
 #endif
-#ifdef PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+#ifdef PNG_HAVE_MMX_READ_FILTER_ROW
                          PNG_ASM_FLAG_MMX_READ_FILTER_SUB   |
                          PNG_ASM_FLAG_MMX_READ_FILTER_UP    |
                          PNG_ASM_FLAG_MMX_READ_FILTER_AVG   |
diff --git a/src/libpng/pngtest.c b/src/libpng/pngtest.c
index 3d09dee3f..299e2947d 100644
--- a/src/libpng/pngtest.c
+++ b/src/libpng/pngtest.c
@@ -1551,4 +1551,4 @@ main(int argc, char *argv[])
 }
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef version_1_2_16 your_png_h_is_not_version_1_2_16;
+typedef version_1_2_18 your_png_h_is_not_version_1_2_18;
diff --git a/src/libpng/pngtrans.c b/src/libpng/pngtrans.c
index 25f42c871..8cb4b8861 100644
--- a/src/libpng/pngtrans.c
+++ b/src/libpng/pngtrans.c
@@ -252,7 +252,7 @@ png_do_swap(png_row_infop row_info, png_bytep row)
 #endif
 
 #if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-static PNG_CONST png_byte onebppswaptable[256] = {
+const static PNG_CONST png_byte onebppswaptable[256] = {
    0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0,
    0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
    0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,
@@ -287,7 +287,7 @@ static PNG_CONST png_byte onebppswaptable[256] = {
    0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
 };
 
-static PNG_CONST png_byte twobppswaptable[256] = {
+const static PNG_CONST png_byte twobppswaptable[256] = {
    0x00, 0x40, 0x80, 0xC0, 0x10, 0x50, 0x90, 0xD0,
    0x20, 0x60, 0xA0, 0xE0, 0x30, 0x70, 0xB0, 0xF0,
    0x04, 0x44, 0x84, 0xC4, 0x14, 0x54, 0x94, 0xD4,
@@ -322,7 +322,7 @@ static PNG_CONST png_byte twobppswaptable[256] = {
    0x2F, 0x6F, 0xAF, 0xEF, 0x3F, 0x7F, 0xBF, 0xFF
 };
 
-static PNG_CONST png_byte fourbppswaptable[256] = {
+const static PNG_CONST png_byte fourbppswaptable[256] = {
    0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70,
    0x80, 0x90, 0xA0, 0xB0, 0xC0, 0xD0, 0xE0, 0xF0,
    0x01, 0x11, 0x21, 0x31, 0x41, 0x51, 0x61, 0x71,
@@ -652,10 +652,11 @@ png_set_user_transform_info(png_structp png_ptr, png_voidp
 png_voidp PNGAPI
 png_get_user_transform_ptr(png_structp png_ptr)
 {
-   if (png_ptr == NULL) return (NULL);
 #if defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
+   if (png_ptr == NULL) return (NULL);
    return ((png_voidp)png_ptr->user_transform_ptr);
-#endif
+#else
    return (NULL);
+#endif
 }
 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
diff --git a/src/libpng/pngwutil.c b/src/libpng/pngwutil.c
index e108c6106..314bea20d 100644
--- a/src/libpng/pngwutil.c
+++ b/src/libpng/pngwutil.c
@@ -523,9 +523,10 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
       png_ptr->zlib_window_bits = 15;
    if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_METHOD))
       png_ptr->zlib_method = 8;
-   deflateInit2(&png_ptr->zstream, png_ptr->zlib_level,
+   if (deflateInit2(&png_ptr->zstream, png_ptr->zlib_level,
       png_ptr->zlib_method, png_ptr->zlib_window_bits,
-      png_ptr->zlib_mem_level, png_ptr->zlib_strategy);
+      png_ptr->zlib_mem_level, png_ptr->zlib_strategy) != Z_OK)
+       png_error(png_ptr, "zlib failed to initialize compressor");
    png_ptr->zstream.next_out = png_ptr->zbuf;
    png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
    /* libpng is not interested in zstream.data_type */