[CHG] libpng updated to version 1.5.4

GRRLIB/lib/png/png.c

@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -14,7 +14,7 @@
 #include "pngpriv.h"
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_5_2 Your_png_h_is_not_version_1_5_2;
+typedef png_libpng_version_1_5_4 Your_png_h_is_not_version_1_5_4;
 
 /* 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
@@ -137,6 +137,61 @@ png_calculate_crc(png_structp png_ptr, png_const_bytep ptr, png_size_t length)
       png_ptr->crc = crc32(png_ptr->crc, ptr, (uInt)length);
 }
 
+/* Check a user supplied version number, called from both read and write
+ * functions that create a png_struct
+ */
+int
+png_user_version_check(png_structp png_ptr, png_const_charp user_png_ver)
+{
+   if (user_png_ver)
+   {
+      int i = 0;
+
+      do
+      {
+         if (user_png_ver[i] != png_libpng_ver[i])
+            png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+      } while (png_libpng_ver[i++]);
+   }
+
+   else
+      png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+
+   if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
+   {
+     /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
+      * we must recompile any applications that use any older library version.
+      * For versions after libpng 1.0, we will be compatible, so we need
+      * only check the first digit.
+      */
+      if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
+          (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
+          (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
+      {
+#ifdef PNG_WARNINGS_SUPPORTED
+         size_t pos = 0;
+         char m[128];
+
+         pos = png_safecat(m, sizeof m, pos, "Application built with libpng-");
+         pos = png_safecat(m, sizeof m, pos, user_png_ver);
+         pos = png_safecat(m, sizeof m, pos, " but running with ");
+         pos = png_safecat(m, sizeof m, pos, png_libpng_ver);
+
+         png_warning(png_ptr, m);
+#endif
+
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+         png_ptr->flags = 0;
+#endif
+
+         return 0;
+      }
+   }
+
+   /* Success return. */
+   return 1;
+}
+
 /* Allocate the memory for an info_struct for the application.  We don't
  * really need the png_ptr, but it could potentially be useful in the
  * future.  This should be used in favour of malloc(png_sizeof(png_info))
@@ -291,12 +346,10 @@ png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask,
    /* Free any sCAL entry */
    if ((mask & PNG_FREE_SCAL) & info_ptr->free_me)
    {
-#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
       png_free(png_ptr, info_ptr->scal_s_width);
       png_free(png_ptr, info_ptr->scal_s_height);
       info_ptr->scal_s_width = NULL;
       info_ptr->scal_s_height = NULL;
-#endif
       info_ptr->valid &= ~PNG_INFO_sCAL;
    }
 #endif
@@ -518,28 +571,37 @@ png_convert_to_rfc1123(png_structp png_ptr, png_const_timep ptime)
    if (png_ptr == NULL)
       return (NULL);
 
-   if (png_ptr->time_buffer == NULL)
    {
-      png_ptr->time_buffer = (png_charp)png_malloc(png_ptr, (png_uint_32)(29*
+      size_t pos = 0;
-         png_sizeof(char)));
+      char number_buf[5]; /* enough for a four digit year */
+
+#     define APPEND_STRING(string)\
+         pos = png_safecat(png_ptr->time_buffer, sizeof png_ptr->time_buffer,\
+            pos, (string))
+#     define APPEND_NUMBER(format, value)\
+         APPEND_STRING(PNG_FORMAT_NUMBER(number_buf, format, (value)))
+#     define APPEND(ch)\
+         if (pos < (sizeof png_ptr->time_buffer)-1)\
+            png_ptr->time_buffer[pos++] = (ch)
+
+      APPEND_NUMBER(PNG_NUMBER_FORMAT_u, (unsigned)ptime->day % 32);
+      APPEND(' ');
+      APPEND_STRING(short_months[(ptime->month - 1) % 12]);
+      APPEND(' ');
+      APPEND_NUMBER(PNG_NUMBER_FORMAT_u, ptime->year);
+      APPEND(' ');
+      APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->hour % 24);
+      APPEND(':');
+      APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->minute % 60);
+      APPEND(':');
+      APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->second % 61);
+      APPEND_STRING(" +0000"); /* This reliably terminates the buffer */
+
+#     undef APPEND
+#     undef APPEND_NUMBER
+#     undef APPEND_STRING
    }
 
-#    ifdef USE_FAR_KEYWORD
-   {
-      char near_time_buf[29];
-      png_snprintf6(near_time_buf, 29, "%d %s %d %02d:%02d:%02d +0000",
-          ptime->day % 32, short_months[(ptime->month - 1) % 12],
-          ptime->year, ptime->hour % 24, ptime->minute % 60,
-          ptime->second % 61);
-      png_memcpy(png_ptr->time_buffer, near_time_buf,
-          29*png_sizeof(char));
-   }
-#    else
-   png_snprintf6(png_ptr->time_buffer, 29, "%d %s %d %02d:%02d:%02d +0000",
-       ptime->day % 32, short_months[(ptime->month - 1) % 12],
-       ptime->year, ptime->hour % 24, ptime->minute % 60,
-       ptime->second % 61);
-#    endif
    return png_ptr->time_buffer;
 }
 #  endif /* PNG_TIME_RFC1123_SUPPORTED */
@@ -555,13 +617,13 @@ png_get_copyright(png_const_structp png_ptr)
 #else
 #  ifdef __STDC__
    return PNG_STRING_NEWLINE \
-     "libpng version 1.5.2 - March 31, 2011" PNG_STRING_NEWLINE \
+     "libpng version 1.5.4 - July 7, 2011" 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 1.5.2 - March 31, 2011\
+      return "libpng version 1.5.4 - July 7, 2011\
       Copyright (c) 1998-2011 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
@@ -681,6 +743,13 @@ png_check_cHRM_fixed(png_structp png_ptr,
    if (png_ptr == NULL)
       return 0;
 
+   /* (x,y,z) values are first limited to 0..100000 (PNG_FP_1), the white
+    * y must also be greater than 0.  To test for the upper limit calculate
+    * (PNG_FP_1-y) - x must be <= to this for z to be >= 0 (and the expression
+    * cannot overflow.)  At this point we know x and y are >= 0 and (x+y) is
+    * <= PNG_FP_1.  The previous test on PNG_MAX_UINT_31 is removed because it
+    * pointless (and it produces compiler warnings!)
+    */
    if (white_x < 0 || white_y <= 0 ||
          red_x < 0 ||   red_y <  0 ||
        green_x < 0 || green_y <  0 ||
@@ -690,38 +759,26 @@ png_check_cHRM_fixed(png_structp png_ptr,
         "Ignoring attempt to set negative chromaticity value");
       ret = 0;
    }
-   if (white_x > (png_fixed_point)PNG_UINT_31_MAX ||
+   /* And (x+y) must be <= PNG_FP_1 (so z is >= 0) */
-       white_y > (png_fixed_point)PNG_UINT_31_MAX ||
+   if (white_x > PNG_FP_1 - white_y)
-         red_x > (png_fixed_point)PNG_UINT_31_MAX ||
-         red_y > (png_fixed_point)PNG_UINT_31_MAX ||
-       green_x > (png_fixed_point)PNG_UINT_31_MAX ||
-       green_y > (png_fixed_point)PNG_UINT_31_MAX ||
-        blue_x > (png_fixed_point)PNG_UINT_31_MAX ||
-        blue_y > (png_fixed_point)PNG_UINT_31_MAX )
-   {
-      png_warning(png_ptr,
-        "Ignoring attempt to set chromaticity value exceeding 21474.83");
-      ret = 0;
-   }
-   if (white_x > 100000L - white_y)
    {
       png_warning(png_ptr, "Invalid cHRM white point");
       ret = 0;
    }
 
-   if (red_x > 100000L - red_y)
+   if (red_x > PNG_FP_1 - red_y)
    {
       png_warning(png_ptr, "Invalid cHRM red point");
       ret = 0;
    }
 
-   if (green_x > 100000L - green_y)
+   if (green_x > PNG_FP_1 - green_y)
    {
       png_warning(png_ptr, "Invalid cHRM green point");
       ret = 0;
    }
 
-   if (blue_x > 100000L - blue_y)
+   if (blue_x > PNG_FP_1 - blue_y)
    {
       png_warning(png_ptr, "Invalid cHRM blue point");
       ret = 0;
@@ -763,7 +820,7 @@ png_check_IHDR(png_structp png_ptr,
    }
 
 #  ifdef PNG_SET_USER_LIMITS_SUPPORTED
-   if (width > png_ptr->user_width_max || width > PNG_USER_WIDTH_MAX)
+   if (width > png_ptr->user_width_max)
 
 #  else
    if (width > PNG_USER_WIDTH_MAX)
@@ -774,7 +831,7 @@ png_check_IHDR(png_structp png_ptr,
    }
 
 #  ifdef PNG_SET_USER_LIMITS_SUPPORTED
-   if (height > png_ptr->user_height_max || height > PNG_USER_HEIGHT_MAX)
+   if (height > png_ptr->user_height_max)
 #  else
    if (height > PNG_USER_HEIGHT_MAX)
 #  endif
@@ -889,16 +946,9 @@ png_check_IHDR(png_structp png_ptr,
 /* Check an ASCII formated floating point value, see the more detailed
  * comments in pngpriv.h
  */
-/* The following is used internally to preserve the 'valid' flag */
+/* The following is used internally to preserve the sticky flags */
 #define png_fp_add(state, flags) ((state) |= (flags))
-#define png_fp_set(state, value)\
+#define png_fp_set(state, value) ((state) = (value) | ((state) & PNG_FP_STICKY))
-   ((state) = (value) | ((state) & PNG_FP_WAS_VALID))
-
-/* Internal type codes: bits above the base state! */
-#define PNG_FP_SIGN   0  /* [+-] */
-#define PNG_FP_DOT    4  /* . */
-#define PNG_FP_DIGIT  8  /* [0123456789] */
-#define PNG_FP_E     12  /* [Ee] */
 
 int /* PRIVATE */
 png_check_fp_number(png_const_charp string, png_size_t size, int *statep,
@@ -911,55 +961,55 @@ png_check_fp_number(png_const_charp string, png_size_t size, int *statep,
    {
       int type;
       /* First find the type of the next character */
+      switch (string[i])
       {
-         char ch = string[i];
+      case 43:  type = PNG_FP_SAW_SIGN;                   break;
-
+      case 45:  type = PNG_FP_SAW_SIGN + PNG_FP_NEGATIVE; break;
-         if (ch >= 48 && ch <= 57)
+      case 46:  type = PNG_FP_SAW_DOT;                    break;
-            type = PNG_FP_DIGIT;
+      case 48:  type = PNG_FP_SAW_DIGIT;                  break;
-
+      case 49: case 50: case 51: case 52:
-         else switch (ch)
+      case 53: case 54: case 55: case 56:
-         {
+      case 57:  type = PNG_FP_SAW_DIGIT + PNG_FP_NONZERO; break;
-         case 43: case 45:  type = PNG_FP_SIGN;  break;
+      case 69:
-         case 46:           type = PNG_FP_DOT;   break;
+      case 101: type = PNG_FP_SAW_E;                      break;
-         case 69: case 101: type = PNG_FP_E;     break;
+      default:  goto PNG_FP_End;
-         default:           goto PNG_FP_End;
-         }
       }
 
       /* Now deal with this type according to the current
        * state, the type is arranged to not overlap the
        * bits of the PNG_FP_STATE.
        */
-      switch ((state & PNG_FP_STATE) + type)
+      switch ((state & PNG_FP_STATE) + (type & PNG_FP_SAW_ANY))
       {
-      case PNG_FP_INTEGER + PNG_FP_SIGN:
+      case PNG_FP_INTEGER + PNG_FP_SAW_SIGN:
          if (state & PNG_FP_SAW_ANY)
             goto PNG_FP_End; /* not a part of the number */
 
-         png_fp_add(state, PNG_FP_SAW_SIGN);
+         png_fp_add(state, type);
          break;
 
-      case PNG_FP_INTEGER + PNG_FP_DOT:
+      case PNG_FP_INTEGER + PNG_FP_SAW_DOT:
          /* Ok as trailer, ok as lead of fraction. */
          if (state & PNG_FP_SAW_DOT) /* two dots */
             goto PNG_FP_End;
 
          else if (state & PNG_FP_SAW_DIGIT) /* trailing dot? */
-            png_fp_add(state, PNG_FP_SAW_DOT);
+            png_fp_add(state, type);
 
          else
-            png_fp_set(state, PNG_FP_FRACTION | PNG_FP_SAW_DOT);
+            png_fp_set(state, PNG_FP_FRACTION | type);
 
          break;
 
-      case PNG_FP_INTEGER + PNG_FP_DIGIT:
+      case PNG_FP_INTEGER + PNG_FP_SAW_DIGIT:
          if (state & PNG_FP_SAW_DOT) /* delayed fraction */
             png_fp_set(state, PNG_FP_FRACTION | PNG_FP_SAW_DOT);
 
-         png_fp_add(state, PNG_FP_SAW_DIGIT + PNG_FP_WAS_VALID);
+         png_fp_add(state, type | PNG_FP_WAS_VALID);
 
          break;
-      case PNG_FP_INTEGER + PNG_FP_E:
+
+      case PNG_FP_INTEGER + PNG_FP_SAW_E:
          if ((state & PNG_FP_SAW_DIGIT) == 0)
             goto PNG_FP_End;
 
@@ -967,17 +1017,17 @@ png_check_fp_number(png_const_charp string, png_size_t size, int *statep,
 
          break;
 
-   /* case PNG_FP_FRACTION + PNG_FP_SIGN:
+   /* case PNG_FP_FRACTION + PNG_FP_SAW_SIGN:
-         goto PNG_FP_End; ** no sign in exponent */
+         goto PNG_FP_End; ** no sign in fraction */
 
-   /* case PNG_FP_FRACTION + PNG_FP_DOT:
+   /* case PNG_FP_FRACTION + PNG_FP_SAW_DOT:
          goto PNG_FP_End; ** Because SAW_DOT is always set */
 
-      case PNG_FP_FRACTION + PNG_FP_DIGIT:
+      case PNG_FP_FRACTION + PNG_FP_SAW_DIGIT:
-         png_fp_add(state, PNG_FP_SAW_DIGIT + PNG_FP_WAS_VALID);
+         png_fp_add(state, type | PNG_FP_WAS_VALID);
          break;
 
-      case PNG_FP_FRACTION + PNG_FP_E:
+      case PNG_FP_FRACTION + PNG_FP_SAW_E:
          /* This is correct because the trailing '.' on an
           * integer is handled above - so we can only get here
           * with the sequence ".E" (with no preceding digits).
@@ -989,7 +1039,7 @@ png_check_fp_number(png_const_charp string, png_size_t size, int *statep,
 
          break;
 
-      case PNG_FP_EXPONENT + PNG_FP_SIGN:
+      case PNG_FP_EXPONENT + PNG_FP_SAW_SIGN:
          if (state & PNG_FP_SAW_ANY)
             goto PNG_FP_End; /* not a part of the number */
 
@@ -997,15 +1047,15 @@ png_check_fp_number(png_const_charp string, png_size_t size, int *statep,
 
          break;
 
-   /* case PNG_FP_EXPONENT + PNG_FP_DOT:
+   /* case PNG_FP_EXPONENT + PNG_FP_SAW_DOT:
          goto PNG_FP_End; */
 
-      case PNG_FP_EXPONENT + PNG_FP_DIGIT:
+      case PNG_FP_EXPONENT + PNG_FP_SAW_DIGIT:
-         png_fp_add(state, PNG_FP_SAW_DIGIT + PNG_FP_WAS_VALID);
+         png_fp_add(state, PNG_FP_SAW_DIGIT | PNG_FP_WAS_VALID);
 
          break;
 
-   /* case PNG_FP_EXPONEXT + PNG_FP_E:
+   /* case PNG_FP_EXPONEXT + PNG_FP_SAW_E:
          goto PNG_FP_End; */
 
       default: goto PNG_FP_End; /* I.e. break 2 */
@@ -1033,8 +1083,11 @@ png_check_fp_string(png_const_charp string, png_size_t size)
    int        state=0;
    png_size_t char_index=0;
 
-   return png_check_fp_number(string, size, &state, &char_index) &&
+   if (png_check_fp_number(string, size, &state, &char_index) &&
-      (char_index == size || string[char_index] == 0);
+      (char_index == size || string[char_index] == 0))
+      return state /* must be non-zero - see above */;
+
+   return 0; /* i.e. fail */
 }
 #endif /* pCAL or sCAL */
 
@@ -1102,7 +1155,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
       if (fp < 0)
       {
          fp = -fp;
-         *ascii++ = 45; /* '-'  PLUS 1 TOTAL 1*/
+         *ascii++ = 45; /* '-'  PLUS 1 TOTAL 1 */
          --size;
       }
 
@@ -1329,7 +1382,7 @@ png_ascii_from_fp(png_structp png_ptr, png_charp ascii, png_size_t size,
              */
             size -= cdigits;
 
-            *ascii++ = 69, --size;    /* 'E': PLUS 1 TOTAL 2+precision*/
+            *ascii++ = 69, --size;    /* 'E': PLUS 1 TOTAL 2+precision */
             if (exp_b10 < 0)
             {
                *ascii++ = 45, --size; /* '-': PLUS 1 TOTAL 3+precision */
@@ -1401,7 +1454,7 @@ png_ascii_from_fixed(png_structp png_ptr, png_charp ascii, png_size_t size,
 
       if (num <= 0x80000000U) /* else overflowed */
       {
-         unsigned int ndigits = 0, first = 16/*flag value*/;
+         unsigned int ndigits = 0, first = 16 /* flag value */;
          char digits[10];
 
          while (num)
@@ -1495,7 +1548,7 @@ png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
          r /= divisor;
          r = floor(r+.5);
 
-         /* A png_fixed_point is a 32 bit integer. */
+         /* A png_fixed_point is a 32-bit integer. */
          if (r <= 2147483647. && r >= -2147483648.)
          {
             *res = (png_fixed_point)r;
@@ -1540,7 +1593,7 @@ png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
 
          if (s32 < D) /* else overflow */
          {
-            /* s32.s00 is now the 64 bit product, do a standard
+            /* s32.s00 is now the 64-bit product, do a standard
              * division, we know that s32 < D, so the maximum
              * required shift is 31.
              */
@@ -1683,7 +1736,7 @@ png_reciprocal2(png_fixed_point a, png_fixed_point b)
  * 2010: moved from pngset.c) */
 /*
  *    Multiply two 32-bit numbers, V1 and V2, using 32-bit
- *    arithmetic, to produce a 64 bit result in the HI/LO words.
+ *    arithmetic, to produce a 64-bit result in the HI/LO words.
  *
  *                  A B
  *                x C D
@@ -1727,17 +1780,17 @@ png_64bit_product (long v1, long v2, unsigned long *hi_product,
 /* Fixed point gamma.
  *
  * To calculate gamma this code implements fast log() and exp() calls using only
- * fixed point arithmetic.  This code has sufficient precision for either 8 or
+ * fixed point arithmetic.  This code has sufficient precision for either 8-bit
- * 16 bit sample values.
+ * or 16-bit sample values.
  *
  * The tables used here were calculated using simple 'bc' programs, but C double
  * precision floating point arithmetic would work fine.  The programs are given
  * at the head of each table.
  *
- * 8 bit log table
+ * 8-bit log table
  *   This is a table of -log(value/255)/log(2) for 'value' in the range 128 to
- *   255, so it's the base 2 logarithm of a normalized 8 bit floating point
+ *   255, so it's the base 2 logarithm of a normalized 8-bit floating point
- *   mantissa.  The numbers are 32 bit fractions.
+ *   mantissa.  The numbers are 32-bit fractions.
  */
 static png_uint_32
 png_8bit_l2[128] =
@@ -1768,10 +1821,10 @@ png_8bit_l2[128] =
    172473545U, 147538590U, 122703574U, 97967701U, 73330182U, 48790236U,
    24347096U, 0U
 #if 0
-   /* The following are the values for 16 bit tables - these work fine for the 8
+   /* The following are the values for 16-bit tables - these work fine for the
-    * bit conversions but produce very slightly larger errors in the 16 bit log
+    * 8-bit conversions but produce very slightly larger errors in the 16-bit
-    * (about 1.2 as opposed to 0.7 absolute error in the final value).  To use
+    * log (about 1.2 as opposed to 0.7 absolute error in the final value).  To
-    * these all the shifts below must be adjusted appropriately.
+    * use these all the shifts below must be adjusted appropriately.
     */
    65166, 64430, 63700, 62976, 62257, 61543, 60835, 60132, 59434, 58741, 58054,
    57371, 56693, 56020, 55352, 54689, 54030, 53375, 52726, 52080, 51439, 50803,
@@ -1788,7 +1841,7 @@ png_8bit_l2[128] =
 #endif
 };
 
-static png_int_32
+PNG_STATIC png_int_32
 png_log8bit(unsigned int x)
 {
    unsigned int lg2 = 0;
@@ -1814,11 +1867,11 @@ png_log8bit(unsigned int x)
    return (png_int_32)((lg2 << 16) + ((png_8bit_l2[x-128]+32768)>>16));
 }
 
-/* The above gives exact (to 16 binary places) log2 values for 8 bit images,
+/* The above gives exact (to 16 binary places) log2 values for 8-bit images,
- * for 16 bit images we use the most significant 8 bits of the 16 bit value to
+ * for 16-bit images we use the most significant 8 bits of the 16-bit value to
  * get an approximation then multiply the approximation by a correction factor
  * determined by the remaining up to 8 bits.  This requires an additional step
- * in the 16 bit case.
+ * in the 16-bit case.
  *
  * We want log2(value/65535), we have log2(v'/255), where:
  *
@@ -1827,8 +1880,8 @@ png_log8bit(unsigned int x)
  *
  * So f is value/v', which is equal to (256+v''/v') since v' is in the range 128
  * to 255 and v'' is in the range 0 to 255 f will be in the range 256 to less
- * than 258.  The final factor also needs to correct for the fact that our 8 bit
+ * than 258.  The final factor also needs to correct for the fact that our 8-bit
- * value is scaled by 255, whereas the 16 bit values must be scaled by 65535.
+ * value is scaled by 255, whereas the 16-bit values must be scaled by 65535.
  *
  * This gives a final formula using a calculated value 'x' which is value/v' and
  * scaling by 65536 to match the above table:
@@ -1838,13 +1891,13 @@ png_log8bit(unsigned int x)
  * Since these numbers are so close to '1' we can use simple linear
  * interpolation between the two end values 256/257 (result -368.61) and 258/257
  * (result 367.179).  The values used below are scaled by a further 64 to give
- * 16 bit precision in the interpolation:
+ * 16-bit precision in the interpolation:
  *
  * Start (256): -23591
  * Zero  (257):      0
  * End   (258):  23499
  */
-static png_int_32
+PNG_STATIC png_int_32
 png_log16bit(png_uint_32 x)
 {
    unsigned int lg2 = 0;
@@ -1865,7 +1918,7 @@ png_log16bit(png_uint_32 x)
    if ((x & 0x8000) == 0)
       lg2 += 1, x <<= 1;
 
-   /* Calculate the base logarithm from the top 8 bits as a 28 bit fractional
+   /* Calculate the base logarithm from the top 8 bits as a 28-bit fractional
     * value.
     */
    lg2 <<= 28;
@@ -1895,18 +1948,18 @@ png_log16bit(png_uint_32 x)
    return (png_int_32)((lg2 + 2048) >> 12);
 }
 
-/* The 'exp()' case must invert the above, taking a 20 bit fixed point
+/* The 'exp()' case must invert the above, taking a 20-bit fixed point
- * logarithmic value and returning a 16 or 8 bit number as appropriate.  In
+ * logarithmic value and returning a 16 or 8-bit number as appropriate.  In
  * each case only the low 16 bits are relevant - the fraction - since the
  * integer bits (the top 4) simply determine a shift.
  *
- * The worst case is the 16 bit distinction between 65535 and 65534, this
+ * The worst case is the 16-bit distinction between 65535 and 65534, this
  * requires perhaps spurious accuracty in the decoding of the logarithm to
  * distinguish log2(65535/65534.5) - 10^-5 or 17 bits.  There is little chance
  * of getting this accuracy in practice.
  *
  * To deal with this the following exp() function works out the exponent of the
- * frational part of the logarithm by using an accurate 32 bit value from the
+ * frational part of the logarithm by using an accurate 32-bit value from the
  * top four fractional bits then multiplying in the remaining bits.
  */
 static png_uint_32
@@ -1915,7 +1968,7 @@ png_32bit_exp[16] =
 #  if PNG_DO_BC
       for (i=0;i<16;++i) { .5 + e(-i/16*l(2))*2^32; }
 #  endif
-   /* NOTE: the first entry is deliberately set to the maximum 32 bit value. */
+   /* NOTE: the first entry is deliberately set to the maximum 32-bit value. */
    4294967295U, 4112874773U, 3938502376U, 3771522796U, 3611622603U, 3458501653U,
    3311872529U, 3171459999U, 3037000500U, 2908241642U, 2784941738U, 2666869345U,
    2553802834U, 2445529972U, 2341847524U, 2242560872U
@@ -1938,12 +1991,12 @@ for (i=11;i>=0;--i){ print i, " ", (1 - e(-(2^i)/65536*l(2))) * 2^(32-i), "\n"}
     0 45425.85339951654943850496
 #endif
 
-static png_uint_32
+PNG_STATIC png_uint_32
 png_exp(png_fixed_point x)
 {
    if (x > 0 && x <= 0xfffff) /* Else overflow or zero (underflow) */
    {
-      /* Obtain a 4 bit approximation */
+      /* Obtain a 4-bit approximation */
       png_uint_32 e = png_32bit_exp[(x >> 12) & 0xf];
 
       /* Incorporate the low 12 bits - these decrease the returned value by
@@ -1986,13 +2039,13 @@ png_exp(png_fixed_point x)
    return 0;
 }
 
-static png_byte
+PNG_STATIC png_byte
 png_exp8bit(png_fixed_point lg2)
 {
-   /* Get a 32 bit value: */
+   /* Get a 32-bit value: */
    png_uint_32 x = png_exp(lg2);
 
-   /* Convert the 32 bit value to 0..255 by multiplying by 256-1, note that the
+   /* Convert the 32-bit value to 0..255 by multiplying by 256-1, note that the
     * second, rounding, step can't overflow because of the first, subtraction,
     * step.
     */
@@ -2000,13 +2053,13 @@ png_exp8bit(png_fixed_point lg2)
    return (png_byte)((x + 0x7fffffU) >> 24);
 }
 
-static png_uint_16
+PNG_STATIC png_uint_16
 png_exp16bit(png_fixed_point lg2)
 {
-   /* Get a 32 bit value: */
+   /* Get a 32-bit value: */
    png_uint_32 x = png_exp(lg2);
 
-   /* Convert the 32 bit value to 0..65535 by multiplying by 65536-1: */
+   /* Convert the 32-bit value to 0..65535 by multiplying by 65536-1: */
    x -= x >> 16;
    return (png_uint_16)((x + 32767U) >> 16);
 }
@@ -2059,9 +2112,9 @@ png_gamma_16bit_correct(unsigned int value, png_fixed_point gamma_val)
 }
 
 /* This does the right thing based on the bit_depth field of the
- * png_struct, interpreting values as 8 or 16 bit.  While the result
+ * png_struct, interpreting values as 8-bit or 16-bit.  While the result
- * is nominally a 16 bit value if bit depth is 8 then the result is
+ * is nominally a 16-bit value if bit depth is 8 then the result is
- * 8 bit (as are the arguments.)
+ * 8-bit (as are the arguments.)
  */
 png_uint_16 /* PRIVATE */
 png_gamma_correct(png_structp png_ptr, unsigned int value,
@@ -2084,7 +2137,7 @@ png_gamma_significant(png_fixed_point gamma_val)
        gamma_val > PNG_FP_1 + PNG_GAMMA_THRESHOLD_FIXED;
 }
 
-/* Internal function to build a single 16 bit table - the table consists of
+/* Internal function to build a single 16-bit table - the table consists of
  * 'num' 256 entry subtables, where 'num' is determined by 'shift' - the amount
  * to shift the input values right (or 16-number_of_signifiant_bits).
  *
@@ -2111,7 +2164,7 @@ png_build_16bit_table(png_structp png_ptr, png_uint_16pp *ptable,
           (png_uint_16p)png_malloc(png_ptr, 256 * png_sizeof(png_uint_16));
 
       /* The 'threshold' test is repeated here because it can arise for one of
-       * the 16 bit tables even if the others don't hit it.
+       * the 16-bit tables even if the others don't hit it.
        */
       if (png_gamma_significant(gamma_val))
       {
@@ -2173,7 +2226,7 @@ png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable,
        (png_uint_16pp)png_calloc(png_ptr, num * png_sizeof(png_uint_16p));
 
    /* 'num' is the number of tables and also the number of low bits of low
-    * bits of the input 16 bit value used to select a table.  Each table is
+    * bits of the input 16-bit value used to select a table.  Each table is
     * itself index by the high 8 bits of the value.
     */
    for (i = 0; i < num; i++)
@@ -2183,24 +2236,24 @@ png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable,
    /* 'gamma_val' is set to the reciprocal of the value calculated above, so
     * pow(out,g) is an *input* value.  'last' is the last input value set.
     *
-    * In the loop 'i' is used to find output values.  Since the output is 8
+    * In the loop 'i' is used to find output values.  Since the output is
-    * bit there are only 256 possible values.  The tables are set up to
+    * 8-bit there are only 256 possible values.  The tables are set up to
     * select the closest possible output value for each input by finding
     * the input value at the boundary between each pair of output values
     * and filling the table up to that boundary with the lower output
     * value.
     *
-    * The boundary values are 0.5,1.5..253.5,254.5.  Since these are 9 bit
+    * The boundary values are 0.5,1.5..253.5,254.5.  Since these are 9-bit
-    * values the code below uses a 16 bit value in i; the values start at
+    * values the code below uses a 16-bit value in i; the values start at
     * 128.5 (for 0.5) and step by 257, for a total of 254 values (the last
     * entries are filled with 255).  Start i at 128 and fill all 'last'
     * table entries <= 'max'
     */
    last = 0;
-   for (i = 0; i < 255; ++i) /* 8 bit output value */
+   for (i = 0; i < 255; ++i) /* 8-bit output value */
    {
       /* Find the corresponding maximum input value */
-      png_uint_16 out = (png_uint_16)(i * 257U); /* 16 bit output value */
+      png_uint_16 out = (png_uint_16)(i * 257U); /* 16-bit output value */
 
       /* Find the boundary value in 16 bits: */
       png_uint_32 bound = png_gamma_16bit_correct(out+128U, gamma_val);
@@ -2223,7 +2276,7 @@ png_build_16to8_table(png_structp png_ptr, png_uint_16pp *ptable,
    }
 }
 
-/* Build a single 8 bit table: same as the 16 bit case but much simpler (and
+/* Build a single 8-bit table: same as the 16-bit case but much simpler (and
  * typically much faster).  Note that libpng currently does no sBIT processing
  * (apparently contrary to the spec) so a 256 entry table is always generated.
  */
@@ -2258,8 +2311,9 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth)
          png_ptr->screen_gamma) : PNG_FP_1);
 
 #if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
+   defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
    defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-     if (png_ptr->transformations & ((PNG_BACKGROUND) | PNG_RGB_TO_GRAY))
+     if (png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY))
      {
         png_build_8bit_table(png_ptr, &png_ptr->gamma_to_1,
             png_reciprocal(png_ptr->gamma));
@@ -2268,7 +2322,7 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth)
             png_ptr->screen_gamma > 0 ?  png_reciprocal(png_ptr->screen_gamma) :
             png_ptr->gamma/* Probably doing rgb_to_gray */);
      }
-#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */
+#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
   }
   else
   {
@@ -2287,7 +2341,7 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth)
      else
         sig_bit = png_ptr->sig_bit.gray;
 
-     /* 16 bit gamma code uses this equation:
+     /* 16-bit gamma code uses this equation:
       *
       *   ov = table[(iv & 0xff) >> gamma_shift][iv >> 8]
       *
@@ -2302,7 +2356,7 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth)
       *
       * So the table 'n' corresponds to all those 'iv' of:
       *
-      *   <all high 8 bit values><n << gamma_shift>..<(n+1 << gamma_shift)-1>
+      *   <all high 8-bit values><n << gamma_shift>..<(n+1 << gamma_shift)-1>
       *
       */
      if (sig_bit > 0 && sig_bit < 16U)
@@ -2311,7 +2365,7 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth)
      else
         shift = 0; /* keep all 16 bits */
 
-     if (png_ptr->transformations & PNG_16_TO_8)
+     if (png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8))
      {
         /* PNG_MAX_GAMMA_8 is the number of bits to keep - effectively
          * the significant bits in the *input* when the output will
@@ -2327,7 +2381,12 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth)
      png_ptr->gamma_shift = shift;
 
 #ifdef PNG_16BIT_SUPPORTED
-     if (png_ptr->transformations & (PNG_16_TO_8 | PNG_BACKGROUND))
+     /* NOTE: prior to 1.5.4 this test used to include PNG_BACKGROUND (now
+      * PNG_COMPOSE).  This effectively smashed the background calculation for
+      * 16-bit output because the 8-bit table assumes the result will be reduced
+      * to 8 bits.
+      */
+     if (png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8))
 #endif
          png_build_16to8_table(png_ptr, &png_ptr->gamma_16_table, shift,
          png_ptr->screen_gamma > 0 ? png_product2(png_ptr->gamma,
@@ -2341,8 +2400,9 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth)
 #endif
 
 #if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
+   defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
    defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-     if (png_ptr->transformations & (PNG_BACKGROUND | PNG_RGB_TO_GRAY))
+     if (png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY))
      {
         png_build_16bit_table(png_ptr, &png_ptr->gamma_16_to_1, shift,
             png_reciprocal(png_ptr->gamma));
@@ -2355,7 +2415,7 @@ png_build_gamma_table(png_structp png_ptr, int bit_depth)
             png_ptr->screen_gamma > 0 ? png_reciprocal(png_ptr->screen_gamma) :
             png_ptr->gamma/* Probably doing rgb_to_gray */);
      }
-#endif /* PNG_READ_BACKGROUND_SUPPORTED || PNG_RGB_TO_GRAY_SUPPORTED */
+#endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
   }
 }
 #endif /* READ_GAMMA */

GRRLIB/lib/png/png.h

@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.5.2 - March 31, 2011
+ * libpng version 1.5.4 - July 7, 2011
  * Copyright (c) 1998-2011 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 1.5.2 - March 31, 2011: Glenn
+ *   libpng versions 0.97, January 1998, through 1.5.4 - July 7, 2011: Glenn
  *   See also "Contributing Authors", below.
  *
  * Note about libpng version numbers:
@@ -150,6 +150,13 @@
  *    1.5.2beta01-03          15    10502  15.so.15.2[.0]
  *    1.5.2rc01-03            15    10502  15.so.15.2[.0]
  *    1.5.2                   15    10502  15.so.15.2[.0]
+ *    1.5.3beta01-10          15    10503  15.so.15.3[.0]
+ *    1.5.3rc01-02            15    10503  15.so.15.3[.0]
+ *    1.5.3beta11             15    10503  15.so.15.3[.0]
+ *    1.5.3 [omitted]
+ *    1.5.4beta01-08          15    10504  15.so.15.4[.0]
+ *    1.5.4rc01               15    10504  15.so.15.4[.0]
+ *    1.5.4                   15    10504  15.so.15.4[.0]
  *
  *   Henceforth the source version will match the shared-library major
  *   and minor numbers; the shared-library major version number will be
@@ -181,7 +188,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.2.6, August 15, 2004, through 1.5.2, March 31, 2011, are
+ * libpng versions 1.2.6, August 15, 2004, through 1.5.4, July 7, 2011, are
  * Copyright (c) 2004, 2006-2011 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:
@@ -293,25 +300,24 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    March 31, 2011
+ *    July 7, 2011
  *
  *    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 1.5.2 are Y2K compliant.  It is my belief that
+ *    upward through 1.5.4 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
+ *    Libpng only has two year fields.  One is a 2-byte unsigned integer
- *    that will hold years up to 65535.  The other two hold the date in text
+ *    that will hold years up to 65535.  The other holds the date in text
  *    format, and will hold years up to 9999.
  *
  *    The integer is
  *        "png_uint_16 year" in png_time_struct.
  *
- *    The strings are
+ *    The string is
- *        "png_charp time_buffer" in png_struct and
+ *        "png_char time_buffer" in png_struct
- *        "near_time_buffer", which is a local character string in png.c.
  *
  *    There are seven time-related functions:
  *        png.c: png_convert_to_rfc_1123() in png.c
@@ -355,9 +361,9 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.5.2"
+#define PNG_LIBPNG_VER_STRING "1.5.4"
 #define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.5.2 - March 31, 2011\n"
+     " libpng version 1.5.4 - July 7, 2011\n"
 
 #define PNG_LIBPNG_VER_SONUM   15
 #define PNG_LIBPNG_VER_DLLNUM  15
@@ -365,7 +371,7 @@
 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
 #define PNG_LIBPNG_VER_MAJOR   1
 #define PNG_LIBPNG_VER_MINOR   5
-#define PNG_LIBPNG_VER_RELEASE 2
+#define PNG_LIBPNG_VER_RELEASE 4
 /* This should match the numeric part of the final component of
  * PNG_LIBPNG_VER_STRING, omitting any leading zero:
  */
@@ -395,7 +401,7 @@
  * 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 10502 /* 1.5.2 */
+#define PNG_LIBPNG_VER 10504 /* 1.5.4 */
 
 /* Library configuration: these options cannot be changed after
  * the library has been built.
@@ -517,7 +523,7 @@ 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_5_2;
+typedef char* png_libpng_version_1_5_4;
 
 /* Three color definitions.  The order of the red, green, and blue, (and the
  * exact size) is not important, although the size of the fields need to
@@ -594,7 +600,7 @@ typedef png_sPLT_t FAR * FAR * png_sPLT_tpp;
  * and whether that contents is compressed or not.  The "key" field
  * points to a regular zero-terminated C string.  The "text", "lang", and
  * "lang_key" fields can be regular C strings, empty strings, or NULL pointers.
- * However, the * structure returned by png_get_text() will always contain
+ * However, the structure returned by png_get_text() will always contain
  * regular zero-terminated C strings (possibly empty), never NULL pointers,
  * so they can be safely used in printf() and other string-handling functions.
  */
@@ -665,12 +671,24 @@ typedef struct png_unknown_chunk_t
     /* libpng-using applications should NOT directly modify this byte. */
     png_byte location; /* mode of operation at read time */
 }
+
+
 png_unknown_chunk;
 typedef png_unknown_chunk FAR * png_unknown_chunkp;
 typedef PNG_CONST png_unknown_chunk FAR * png_const_unknown_chunkp;
 typedef png_unknown_chunk FAR * FAR * png_unknown_chunkpp;
 #endif
 
+/* Values for the unknown chunk location byte */
+
+#define PNG_HAVE_IHDR  0x01
+#define PNG_HAVE_PLTE  0x02
+#define PNG_AFTER_IDAT 0x08
+
+/* The complete definition of png_info has, as of libpng-1.5.0,
+ * been moved into a separate header file that is not accessible to
+ * applications.  Read libpng-manual.txt or libpng.3 for more info.
+ */
 typedef struct png_info_def png_info;
 typedef png_info FAR * png_infop;
 typedef PNG_CONST png_info FAR * png_const_infop;
@@ -686,6 +704,8 @@ typedef png_info FAR * FAR * png_infopp;
  */
 #define PNG_FP_1    100000
 #define PNG_FP_HALF  50000
+#define PNG_FP_MAX  ((png_fixed_point)0x7fffffffL)
+#define PNG_FP_MIN  (-PNG_FP_MAX)
 
 /* These describe the color_type field in png_info. */
 /* color type masks */
@@ -792,6 +812,14 @@ typedef struct png_row_info_struct
 typedef png_row_info FAR * png_row_infop;
 typedef png_row_info FAR * FAR * png_row_infopp;
 
+/* The complete definition of png_struct has, as of libpng-1.5.0,
+ * been moved into a separate header file that is not accessible to
+ * applications.  Read libpng-manual.txt or libpng.3 for more info.
+ */
+typedef struct png_struct_def png_struct;
+typedef PNG_CONST png_struct FAR * png_const_structp;
+typedef png_struct FAR * png_structp;
+
 /* These are the function types for the I/O functions and for the functions
  * that allow the user to override the default I/O functions with his or her
  * own.  The png_error_ptr type should match that of user-supplied warning
@@ -800,10 +828,6 @@ typedef png_row_info FAR * FAR * png_row_infopp;
  * modify the buffer it is passed. The 'read' function, on the other hand, is
  * expected to return the read data in the buffer.
  */
-typedef struct png_struct_def png_struct;
-typedef PNG_CONST png_struct FAR * png_const_structp;
-typedef png_struct FAR * png_structp;
-
 typedef PNG_CALLBACK(void, *png_error_ptr, (png_structp, png_const_charp));
 typedef PNG_CALLBACK(void, *png_rw_ptr, (png_structp, png_bytep, png_size_t));
 typedef PNG_CALLBACK(void, *png_flush_ptr, (png_structp));
@@ -845,25 +869,18 @@ typedef PNG_CALLBACK(void, *png_unknown_chunk_ptr, (png_structp));
 #endif
 
 #ifdef PNG_SETJMP_SUPPORTED
-/* This must match the function definition in <setjmp.h>, and the
+/* This must match the function definition in <setjmp.h>, and the application
- * application must include this before png.h to obtain the definition
+ * must include this before png.h to obtain the definition of jmp_buf.  The
- * of jmp_buf.  The function is required to be PNG_NORETURN.  (Note that
+ * function is required to be PNG_NORETURN, but this is not checked.  If the
- * PNG_PTR_NORETURN is used here because current versions of the Microsoft
+ * function does return the application will crash via an abort() or similar
- * C compiler do not support the PNG_NORETURN attribute on a pointer.)
+ * system level call.
  *
- * If you get a type warning from the compiler when linking against this line
+ * If you get a warning here while building the library you may need to make
- * then your compiler has 'longjmp' that does not match the requirements of the
- * compiler that built libpng.  You will have to write a wrapper function for
- * your compiler's longjmp and call png_set_longjmp_fn directly (not via the
- * png_jmpbuf macro.)
- *
- * If you get a warning here while building the library you will need to make
  * changes to ensure that pnglibconf.h records the calling convention used by
  * your compiler.  This may be very difficult - try using a different compiler
  * to build the library!
  */
-typedef PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)),
+PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)), typedef);
-   PNG_PTR_NORETURN);
 #endif
 
 /* Transform masks for the high-level interface */
@@ -885,6 +902,9 @@ typedef PNG_FUNCTION(void, (PNGCAPI *png_longjmp_ptr), PNGARG((jmp_buf, int)),
 #define PNG_TRANSFORM_STRIP_FILLER_AFTER 0x1000 /* write only */
 /* Added to libpng-1.4.0 */
 #define PNG_TRANSFORM_GRAY_TO_RGB   0x2000      /* read only */
+/* Added to libpng-1.5.4 */
+#define PNG_TRANSFORM_EXPAND_16     0x4000      /* read only */
+#define PNG_TRANSFORM_SCALE_16      0x8000      /* read only */
 
 /* Flags for MNG supported features */
 #define PNG_FLAG_MNG_EMPTY_PLTE     0x01
@@ -1079,7 +1099,7 @@ PNG_EXPORT(29, void, png_set_tRNS_to_alpha, (png_structp png_ptr));
 #endif
 
 #ifdef PNG_READ_EXPAND_16_SUPPORTED
-/* Expand to 16 bit channels, forces conversion of palette to RGB and expansion
+/* Expand to 16-bit channels, forces conversion of palette to RGB and expansion
  * of a tRNS chunk if present.
  */
 PNG_EXPORT(221, void, png_set_expand_16, (png_structp png_ptr));
@@ -1106,8 +1126,219 @@ PNG_EXPORT(34, png_byte, png_get_rgb_to_gray_status, (png_const_structp
     png_ptr));
 #endif
 
+#ifdef PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
 PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth,
     png_colorp palette));
+#endif
+
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+/* How the alpha channel is interpreted - this affects how the color channels of
+ * a PNG file are returned when an alpha channel, or tRNS chunk in a palette
+ * file, is present.
+ *
+ * This has no effect on the way pixels are written into a PNG output
+ * datastream. The color samples in a PNG datastream are never premultiplied
+ * with the alpha samples.
+ *
+ * The default is to return data according to the PNG specification: the alpha
+ * channel is a linear measure of the contribution of the pixel to the
+ * corresponding composited pixel.  The gamma encoded color channels must be
+ * scaled according to the contribution and to do this it is necessary to undo
+ * the encoding, scale the color values, perform the composition and reencode
+ * the values.  This is the 'PNG' mode.
+ *
+ * The alternative is to 'associate' the alpha with the color information by
+ * storing color channel values that have been scaled by the alpha.  The
+ * advantage is that the color channels can be resampled (the image can be
+ * scaled) in this form.  The disadvantage is that normal practice is to store
+ * linear, not (gamma) encoded, values and this requires 16-bit channels for
+ * still images rather than the 8-bit channels that are just about sufficient if
+ * gamma encoding is used.  In addition all non-transparent pixel values,
+ * including completely opaque ones, must be gamma encoded to produce the final
+ * image.  This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the
+ * latter being the two common names for associated alpha color channels.)
+ *
+ * Since it is not necessary to perform arithmetic on opaque color values so
+ * long as they are not to be resampled and are in the final color space it is
+ * possible to optimize the handling of alpha by storing the opaque pixels in
+ * the PNG format (adjusted for the output color space) while storing partially
+ * opaque pixels in the standard, linear, format.  The accuracy required for
+ * standard alpha composition is relatively low, because the pixels are
+ * isolated, therefore typically the accuracy loss in storing 8-bit linear
+ * values is acceptable.  (This is not true if the alpha channel is used to
+ * simulate transparency over large areas - use 16 bits or the PNG mode in
+ * this case!)  This is the 'OPTIMIZED' mode.  For this mode a pixel is
+ * treated as opaque only if the alpha value is equal to the maximum value.
+ *
+ * The final choice is to gamma encode the alpha channel as well.  This is
+ * broken because, in practice, no implementation that uses this choice
+ * correctly undoes the encoding before handling alpha composition.  Use this
+ * choice only if other serious errors in the software or hardware you use
+ * mandate it; the typical serious error is for dark halos to appear around
+ * opaque areas of the composited PNG image because of arithmetic overflow.
+ *
+ * The API function png_set_alpha_mode specifies which of these choices to use
+ * with an enumerated 'mode' value and the gamma of the required output:
+ */
+#define PNG_ALPHA_PNG           0 /* according to the PNG standard */
+#define PNG_ALPHA_STANDARD      1 /* according to Porter/Duff */
+#define PNG_ALPHA_ASSOCIATED    1 /* as above; this is the normal practice */
+#define PNG_ALPHA_PREMULTIPLIED 1 /* as above */
+#define PNG_ALPHA_OPTIMIZED     2 /* 'PNG' for opaque pixels, else 'STANDARD' */
+#define PNG_ALPHA_BROKEN        3 /* the alpha channel is gamma encoded */
+
+PNG_FP_EXPORT(227, void, png_set_alpha_mode, (png_structp png_ptr, int mode,
+    double output_gamma));
+PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structp png_ptr,
+    int mode, png_fixed_point output_gamma));
+#endif
+
+#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED)
+/* The output_gamma value is a screen gamma in libpng terminology: it expresses
+ * how to decode the output values, not how they are encoded.  The values used
+ * correspond to the normal numbers used to describe the overall gamma of a
+ * computer display system; for example 2.2 for an sRGB conformant system.  The
+ * values are scaled by 100000 in the _fixed version of the API (so 220000 for
+ * sRGB.)
+ *
+ * The inverse of the value is always used to provide a default for the PNG file
+ * encoding if it has no gAMA chunk and if png_set_gamma() has not been called
+ * to override the PNG gamma information.
+ *
+ * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode
+ * opaque pixels however pixels with lower alpha values are not encoded,
+ * regardless of the output gamma setting.
+ *
+ * When the standard Porter Duff handling is requested with mode 1 the output
+ * encoding is set to be linear and the output_gamma value is only relevant
+ * as a default for input data that has no gamma information.  The linear output
+ * encoding will be overridden if png_set_gamma() is called - the results may be
+ * highly unexpected!
+ *
+ * The following numbers are derived from the sRGB standard and the research
+ * behind it.  sRGB is defined to be approximated by a PNG gAMA chunk value of
+ * 0.45455 (1/2.2) for PNG.  The value implicitly includes any viewing
+ * correction required to take account of any differences in the color
+ * environment of the original scene and the intended display environment; the
+ * value expresses how to *decode* the image for display, not how the original
+ * data was *encoded*.
+ *
+ * sRGB provides a peg for the PNG standard by defining a viewing environment.
+ * sRGB itself, and earlier TV standards, actually use a more complex transform
+ * (a linear portion then a gamma 2.4 power law) than PNG can express.  (PNG is
+ * limited to simple power laws.)  By saying that an image for direct display on
+ * an sRGB conformant system should be stored with a gAMA chunk value of 45455
+ * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification
+ * makes it possible to derive values for other display systems and
+ * environments.
+ *
+ * The Mac value is deduced from the sRGB based on an assumption that the actual
+ * extra viewing correction used in early Mac display systems was implemented as
+ * a power 1.45 lookup table.
+ *
+ * Any system where a programmable lookup table is used or where the behavior of
+ * the final display device characteristics can be changed requires system
+ * specific code to obtain the current characteristic.  However this can be
+ * difficult and most PNG gamma correction only requires an approximate value.
+ *
+ * By default, if png_set_alpha_mode() is not called, libpng assumes that all
+ * values are unencoded, linear, values and that the output device also has a
+ * linear characteristic.  This is only very rarely correct - it is invariably
+ * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the
+ * default if you don't know what the right answer is!
+ *
+ * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS
+ * 10.6) which used a correction table to implement a somewhat lower gamma on an
+ * otherwise sRGB system.
+ *
+ * Both these values are reserved (not simple gamma values) in order to allow
+ * more precise correction internally in the future.
+ *
+ * NOTE: the following values can be passed to either the fixed or floating
+ * point APIs, but the floating point API will also accept floating point
+ * values.
+ */
+#define PNG_DEFAULT_sRGB -1       /* sRGB gamma and color space */
+#define PNG_GAMMA_MAC_18 -2       /* Old Mac '1.8' gamma and color space */
+#define PNG_GAMMA_sRGB   220000   /* Television standards--matches sRGB gamma */
+#define PNG_GAMMA_LINEAR PNG_FP_1 /* Linear */
+#endif
+
+/* The following are examples of calls to png_set_alpha_mode to achieve the
+ * required overall gamma correction and, where necessary, alpha
+ * premultiplication.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
+ *    This is the default libpng handling of the alpha channel - it is not
+ *    pre-multiplied into the color components.  In addition the call states
+ *    that the output is for a sRGB system and causes all PNG files without gAMA
+ *    chunks to be assumed to be encoded using sRGB.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
+ *    In this case the output is assumed to be something like an sRGB conformant
+ *    display preceeded by a power-law lookup table of power 1.45.  This is how
+ *    early Mac systems behaved.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_GAMMA_LINEAR);
+ *    This is the classic Jim Blinn approach and will work in academic
+ *    environments where everything is done by the book.  It has the shortcoming
+ *    of assuming that input PNG data with no gamma information is linear - this
+ *    is unlikely to be correct unless the PNG files where generated locally.
+ *    Most of the time the output precision will be so low as to show
+ *    significant banding in dark areas of the image.
+ *
+ * png_set_expand_16(pp);
+ * png_set_alpha_mode(pp, PNG_ALPHA_STANDARD, PNG_DEFAULT_sRGB);
+ *    This is a somewhat more realistic Jim Blinn inspired approach.  PNG files
+ *    are assumed to have the sRGB encoding if not marked with a gamma value and
+ *    the output is always 16 bits per component.  This permits accurate scaling
+ *    and processing of the data.  If you know that your input PNG files were
+ *    generated locally you might need to replace PNG_DEFAULT_sRGB with the
+ *    correct value for your system.
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_OPTIMIZED, PNG_DEFAULT_sRGB);
+ *    If you just need to composite the PNG image onto an existing background
+ *    and if you control the code that does this you can use the optimization
+ *    setting.  In this case you just copy completely opaque pixels to the
+ *    output.  For pixels that are not completely transparent (you just skip
+ *    those) you do the composition math using png_composite or png_composite_16
+ *    below then encode the resultant 8-bit or 16-bit values to match the output
+ *    encoding.
+ *
+ * Other cases
+ *    If neither the PNG nor the standard linear encoding work for you because
+ *    of the software or hardware you use then you have a big problem.  The PNG
+ *    case will probably result in halos around the image.  The linear encoding
+ *    will probably result in a washed out, too bright, image (it's actually too
+ *    contrasty.)  Try the ALPHA_OPTIMIZED mode above - this will probably
+ *    substantially reduce the halos.  Alternatively try:
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_BROKEN, PNG_DEFAULT_sRGB);
+ *    This option will also reduce the halos, but there will be slight dark
+ *    halos round the opaque parts of the image where the background is light.
+ *    In the OPTIMIZED mode the halos will be light halos where the background
+ *    is dark.  Take your pick - the halos are unavoidable unless you can get
+ *    your hardware/software fixed!  (The OPTIMIZED approach is slightly
+ *    faster.)
+ *
+ * When the default gamma of PNG files doesn't match the output gamma.
+ *    If you have PNG files with no gamma information png_set_alpha_mode allows
+ *    you to provide a default gamma, but it also sets the ouput gamma to the
+ *    matching value.  If you know your PNG files have a gamma that doesn't
+ *    match the output you can take advantage of the fact that
+ *    png_set_alpha_mode always sets the output gamma but only sets the PNG
+ *    default if it is not already set:
+ *
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_DEFAULT_sRGB);
+ * png_set_alpha_mode(pp, PNG_ALPHA_PNG, PNG_GAMMA_MAC);
+ *    The first call sets both the default and the output gamma values, the
+ *    second call overrides the output gamma without changing the default.  This
+ *    is easier than achieving the same effect with png_set_gamma.  You must use
+ *    PNG_ALPHA_PNG for the first call - internal checking in png_set_alpha will
+ *    fire if more than one call to png_set_alpha_mode and png_set_background is
+ *    made in the same read operation, however multiple calls with PNG_ALPHA_PNG
+ *    are ignored.
+ */
 
 #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
 PNG_EXPORT(36, void, png_set_strip_alpha, (png_structp png_ptr));
@@ -1175,7 +1406,11 @@ PNG_EXPORT(46, void, png_set_invert_mono, (png_structp png_ptr));
 #endif
 
 #ifdef PNG_READ_BACKGROUND_SUPPORTED
-/* Handle alpha and tRNS by replacing with a background color. */
+/* Handle alpha and tRNS by replacing with a background color.  Prior to
+ * libpng-1.5.4 this API must not be called before the PNG file header has been
+ * read.  Doing so will result in unexpected behavior and possible warnings or
+ * errors if the PNG file contains a bKGD chunk.
+ */
 PNG_FP_EXPORT(47, void, png_set_background, (png_structp png_ptr,
     png_const_color_16p background_color, int background_gamma_code,
     int need_expand, double background_gamma));
@@ -1190,7 +1425,13 @@ PNG_FIXED_EXPORT(215, void, png_set_background_fixed, (png_structp png_ptr,
 #  define PNG_BACKGROUND_GAMMA_UNIQUE  3
 #endif
 
-#ifdef PNG_READ_16_TO_8_SUPPORTED
+#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+/* Scale a 16-bit depth file down to 8-bit, accurately. */
+PNG_EXPORT(229, void, png_set_scale_16, (png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
+#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_structp png_ptr));
 #endif
@@ -1211,12 +1452,22 @@ PNG_EXPORT(49, void, png_set_quantize,
  */
 #define PNG_GAMMA_THRESHOLD (PNG_GAMMA_THRESHOLD_FIXED*.00001)
 
-/* Handle gamma correction. Screen_gamma=(display_exponent) */
+/* Handle gamma correction. Screen_gamma=(display_exponent).
+ * NOTE: this API simply sets the screen and file gamma values. It will
+ * therefore override the value for gamma in a PNG file if it is called after
+ * the file header has been read - use with care  - call before reading the PNG
+ * file for best results!
+ *
+ * These routines accept the same gamma values as png_set_alpha_mode (described
+ * above).  The PNG_GAMMA_ defines and PNG_DEFAULT_sRGB can be passed to either
+ * API (floating point or fixed.)  Notice, however, that the 'file_gamma' value
+ * is the inverse of a 'screen gamma' value.
+ */
 PNG_FP_EXPORT(50, void, png_set_gamma,
     (png_structp png_ptr, double screen_gamma,
-    double default_file_gamma));
+    double override_file_gamma));
 PNG_FIXED_EXPORT(208, void, png_set_gamma_fixed, (png_structp png_ptr,
-    png_fixed_point screen_gamma, png_fixed_point default_file_gamma));
+    png_fixed_point screen_gamma, png_fixed_point override_file_gamma));
 #endif
 
 #ifdef PNG_WRITE_FLUSH_SUPPORTED
@@ -1391,6 +1642,7 @@ PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed,
 #define PNG_FILTER_HEURISTIC_WEIGHTED   2  /* Experimental feature */
 #define PNG_FILTER_HEURISTIC_LAST       3  /* Not a valid value */
 
+#ifdef PNG_WRITE_SUPPORTED
 /* Set the library compression level.  Currently, valid values range from
  * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
  * (0 - no compression, 9 - "maximal" compression).  Note that tests have
@@ -1407,11 +1659,36 @@ PNG_EXPORT(70, void, png_set_compression_mem_level, (png_structp png_ptr,
 PNG_EXPORT(71, void, png_set_compression_strategy, (png_structp png_ptr,
     int strategy));
 
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
 PNG_EXPORT(72, void, png_set_compression_window_bits, (png_structp png_ptr,
     int window_bits));
 
 PNG_EXPORT(73, void, png_set_compression_method, (png_structp png_ptr,
     int method));
+#endif
+
+#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
+/* Also set zlib parameters for compressing non-IDAT chunks */
+PNG_EXPORT(222, void, png_set_text_compression_level,
+    (png_structp png_ptr, int level));
+
+PNG_EXPORT(223, void, png_set_text_compression_mem_level, (png_structp png_ptr,
+    int mem_level));
+
+PNG_EXPORT(224, void, png_set_text_compression_strategy, (png_structp png_ptr,
+    int strategy));
+
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
+PNG_EXPORT(225, void, png_set_text_compression_window_bits, (png_structp
+    png_ptr, int window_bits));
+
+PNG_EXPORT(226, void, png_set_text_compression_method, (png_structp png_ptr,
+    int method));
+#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
 
 /* These next functions are called for input/output, memory, and error
  * handling.  They are in the file pngrio.c, pngwio.c, and pngerror.c,
@@ -1623,6 +1900,7 @@ PNG_EXPORTA(103, void, png_chunk_error, (png_structp png_ptr,
 PNG_EXPORTA(104, void, png_err, (png_structp png_ptr), PNG_NORETURN);
 #endif
 
+#ifdef PNG_WARNINGS_SUPPORTED
 /* Non-fatal error in libpng.  Can continue, but may have a problem. */
 PNG_EXPORT(105, void, png_warning, (png_structp png_ptr,
     png_const_charp warning_message));
@@ -1630,6 +1908,7 @@ PNG_EXPORT(105, void, png_warning, (png_structp png_ptr,
 /* Non-fatal error in libpng, chunk name is prepended to message. */
 PNG_EXPORT(106, void, png_chunk_warning, (png_structp png_ptr,
     png_const_charp warning_message));
+#endif
 
 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
 /* Benign error in libpng.  Can continue, but may have a problem.
@@ -2297,7 +2576,7 @@ 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(221);
+  PNG_EXPORT_LAST_ORDINAL(229);
 #endif
 
 #ifdef __cplusplus

GRRLIB/lib/png/pngconf.h

@@ -1,7 +1,7 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.5.2 - March 31, 2011
+ * libpng version 1.5.4 - July 7, 2011
  *
  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -353,23 +353,6 @@
 #    ifndef PNG_NORETURN
 #      define PNG_NORETURN   __attribute__((__noreturn__))
 #    endif
-#    ifndef PNG_PTR_NORETURN
-       /* It's not enough to have the compiler be the correct compiler at
-        * this point - it's necessary for the library (which defines
-        * the type of the library longjmp) to also be the GNU library.
-        * This is because many systems use the GNU compiler with a
-        * non-GNU libc implementation.  Min/GW headers are also compatible
-        * with GCC as well as uclibc, so it seems best to exclude known
-        * problem libcs here rather than just including known libcs.
-        *
-        * NOTE: this relies on the only use of PNG_PTR_NORETURN being with
-        * the system longjmp.  If the same type is used elsewhere then this
-        * will need to be changed.
-        */
-#      if !defined(__CYGWIN__)
-#         define PNG_PTR_NORETURN   __attribute__((__noreturn__))
-#      endif
-#    endif
 #    ifndef PNG_ALLOCATED
 #      define PNG_ALLOCATED  __attribute__((__malloc__))
 #    endif
@@ -382,9 +365,6 @@
 #      ifndef PNG_DEPRECATED
 #        define PNG_DEPRECATED __attribute__((__deprecated__))
 #      endif
-#      ifndef PNG_DEPSTRUCT
-#        define PNG_DEPSTRUCT  __attribute__((__deprecated__))
-#      endif
 #      ifndef PNG_PRIVATE
 #        if 0 /* Doesn't work so we use deprecated instead*/
 #          define PNG_PRIVATE \
@@ -404,11 +384,10 @@
 #    ifndef PNG_NORETURN
 #      define PNG_NORETURN   __declspec(noreturn)
 #    endif
-#    ifndef PNG_PTR_NORETURN
-#      define PNG_PTR_NORETURN /* not supported */
-#    endif
 #    ifndef PNG_ALLOCATED
-#      define PNG_ALLOCATED __declspec(restrict)
+#      if (_MSC_VER >= 1400)
+#        define PNG_ALLOCATED __declspec(restrict)
+#      endif
 #    endif
 
     /* This specifically protects structure members that should only be
@@ -419,9 +398,6 @@
 #      ifndef PNG_DEPRECATED
 #        define PNG_DEPRECATED __declspec(deprecated)
 #      endif
-#      ifndef PNG_DEPSTRUCT
-#        define PNG_DEPSTRUCT  __declspec(deprecated)
-#      endif
 #      ifndef PNG_PRIVATE
 #        define PNG_PRIVATE __declspec(deprecated)
 #      endif
@@ -438,15 +414,9 @@
 #ifndef PNG_NORETURN
 #  define PNG_NORETURN    /* This function does not return */
 #endif
-#ifndef PNG_PTR_NORETURN
-#  define PNG_PTR_NORETURN /* This function does not return */
-#endif
 #ifndef PNG_ALLOCATED
 #  define PNG_ALLOCATED   /* The result of the function is new memory */
 #endif
-#ifndef PNG_DEPSTRUCT
-#  define PNG_DEPSTRUCT   /* Access to this struct member is deprecated */
-#endif
 #ifndef PNG_PRIVATE
 #  define PNG_PRIVATE     /* This is a private libpng function */
 #endif

GRRLIB/lib/png/pngerror.c

@@ -1,7 +1,7 @@
 
 /* pngerror.c - stub functions for i/o and memory allocation
  *
- * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  * Copyright (c) 1998-2011 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.)
@@ -89,15 +89,121 @@ png_error,(png_structp png_ptr, png_const_charp error_message),PNG_NORETURN)
 PNG_FUNCTION(void,PNGAPI
 png_err,(png_structp png_ptr),PNG_NORETURN)
 {
+   /* Prior to 1.5.2 the error_fn received a NULL pointer, expressed
+    * erroneously as '\0', instead of the empty string "".  This was
+    * apparently an error, introduced in libpng-1.2.20, and png_default_error
+    * will crash in this case.
+    */
    if (png_ptr != NULL && png_ptr->error_fn != NULL)
-      (*(png_ptr->error_fn))(png_ptr, '\0');
+      (*(png_ptr->error_fn))(png_ptr, "");
 
    /* If the custom handler doesn't exist, or if it returns,
       use the default handler, which will not return. */
-   png_default_error(png_ptr, '\0');
+   png_default_error(png_ptr, "");
 }
 #endif /* PNG_ERROR_TEXT_SUPPORTED */
 
+/* Utility to safely appends strings to a buffer.  This never errors out so
+ * error checking is not required in the caller.
+ */
+size_t
+png_safecat(png_charp buffer, size_t bufsize, size_t pos,
+   png_const_charp string)
+{
+   if (buffer != NULL && pos < bufsize)
+   {
+      if (string != NULL)
+         while (*string != '\0' && pos < bufsize-1)
+           buffer[pos++] = *string++;
+
+      buffer[pos] = '\0';
+   }
+
+   return pos;
+}
+
+#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
+/* Utility to dump an unsigned value into a buffer, given a start pointer and
+ * and end pointer (which should point just *beyond* the end of the buffer!)
+ * Returns the pointer to the start of the formatted string.
+ */
+png_charp
+png_format_number(png_const_charp start, png_charp end, int format,
+   png_alloc_size_t number)
+{
+   int count = 0;    /* number of digits output */
+   int mincount = 1; /* minimum number required */
+   int output = 0;   /* digit output (for the fixed point format) */
+
+   *--end = '\0';
+
+   /* This is written so that the loop always runs at least once, even with
+    * number zero.
+    */
+   while (end > start && (number != 0 || count < mincount))
+   {
+
+      static const char digits[] = "0123456789ABCDEF";
+
+      switch (format)
+      {
+         case PNG_NUMBER_FORMAT_fixed:
+            /* Needs five digits (the fraction) */
+            mincount = 5;
+            if (output || number % 10 != 0)
+            {
+               *--end = digits[number % 10];
+               output = 1;
+            }
+            number /= 10;
+            break;
+
+         case PNG_NUMBER_FORMAT_02u:
+            /* Expects at least 2 digits. */
+            mincount = 2;
+            /* fall through */
+
+         case PNG_NUMBER_FORMAT_u:
+            *--end = digits[number % 10];
+            number /= 10;
+            break;
+
+         case PNG_NUMBER_FORMAT_02x:
+            /* This format expects at least two digits */
+            mincount = 2;
+            /* fall through */
+
+         case PNG_NUMBER_FORMAT_x:
+            *--end = digits[number & 0xf];
+            number >>= 4;
+            break;
+
+         default: /* an error */
+            number = 0;
+            break;
+      }
+
+      /* Keep track of the number of digits added */
+      ++count;
+
+      /* Float a fixed number here: */
+      if (format == PNG_NUMBER_FORMAT_fixed) if (count == 5) if (end > start)
+      {
+         /* End of the fraction, but maybe nothing was output?  In that case
+          * drop the decimal point.  If the number is a true zero handle that
+          * here.
+          */
+         if (output)
+            *--end = '.';
+         else if (number == 0) /* and !output */
+            *--end = '0';
+      }
+   }
+
+   return end;
+}
+#endif
+
 #ifdef PNG_WARNINGS_SUPPORTED
 /* This function is called whenever there is a non-fatal error.  This function
  * should not be changed.  If there is a need to handle warnings differently,
@@ -128,6 +234,115 @@ png_warning(png_structp png_ptr, png_const_charp warning_message)
    else
       png_default_warning(png_ptr, warning_message + offset);
 }
+
+/* These functions support 'formatted' warning messages with up to
+ * PNG_WARNING_PARAMETER_COUNT parameters.  In the format string the parameter
+ * is introduced by @<number>, where 'number' starts at 1.  This follows the
+ * standard established by X/Open for internationalizable error messages.
+ */
+void
+png_warning_parameter(png_warning_parameters p, int number,
+   png_const_charp string)
+{
+   if (number > 0 && number <= PNG_WARNING_PARAMETER_COUNT)
+      (void)png_safecat(p[number-1], (sizeof p[number-1]), 0, string);
+}
+
+void
+png_warning_parameter_unsigned(png_warning_parameters p, int number, int format,
+   png_alloc_size_t value)
+{
+   char buffer[PNG_NUMBER_BUFFER_SIZE];
+   png_warning_parameter(p, number, PNG_FORMAT_NUMBER(buffer, format, value));
+}
+
+void
+png_warning_parameter_signed(png_warning_parameters p, int number, int format,
+   png_int_32 value)
+{
+   png_alloc_size_t u;
+   png_charp str;
+   char buffer[PNG_NUMBER_BUFFER_SIZE];
+
+   /* Avoid overflow by doing the negate in a png_alloc_size_t: */
+   u = (png_alloc_size_t)value;
+   if (value < 0)
+      u = ~u + 1;
+
+   str = PNG_FORMAT_NUMBER(buffer, format, u);
+
+   if (value < 0 && str > buffer)
+      *--str = '-';
+
+   png_warning_parameter(p, number, str);
+}
+
+void
+png_formatted_warning(png_structp png_ptr, png_warning_parameters p,
+   png_const_charp message)
+{
+   /* The internal buffer is just 128 bytes - enough for all our messages,
+    * overflow doesn't happen because this code checks!
+    */
+   size_t i;
+   char msg[128];
+
+   for (i=0; i<(sizeof msg)-1 && *message != '\0'; ++i)
+   {
+      if (*message == '@')
+      {
+         int parameter = -1;
+         switch (*++message)
+         {
+            case '1':
+               parameter = 0;
+               break;
+
+            case '2':
+               parameter = 1;
+               break;
+
+            case '\0':
+               continue; /* To break out of the for loop above. */
+
+            default:
+               break;
+         }
+
+         if (parameter >= 0 && parameter < PNG_WARNING_PARAMETER_COUNT)
+         {
+            /* Append this parameter */
+            png_const_charp parm = p[parameter];
+            png_const_charp pend = p[parameter] + (sizeof p[parameter]);
+
+            /* No need to copy the trailing '\0' here, but there is no guarantee
+             * that parm[] has been initialized, so there is no guarantee of a
+             * trailing '\0':
+             */
+            for (; i<(sizeof msg)-1 && parm != '\0' && parm < pend; ++i)
+               msg[i] = *parm++;
+
+            ++message;
+            continue;
+         }
+
+         /* else not a parameter and there is a character after the @ sign; just
+          * copy that.
+          */
+      }
+
+      /* At this point *message can't be '\0', even in the bad parameter case
+       * above where there is a lone '@' at the end of the message string.
+       */
+      msg[i] = *message++;
+   }
+
+   /* i is always less than (sizeof msg), so: */
+   msg[i] = '\0';
+
+   /* And this is the formatted message: */
+   png_warning(png_ptr, msg);
+}
 #endif /* PNG_WARNINGS_SUPPORTED */
 
 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
@@ -185,8 +400,13 @@ png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp
    {
       buffer[iout++] = ':';
       buffer[iout++] = ' ';
-      png_memcpy(buffer + iout, error_message, PNG_MAX_ERROR_TEXT);
+
-      buffer[iout + PNG_MAX_ERROR_TEXT - 1] = '\0';
+      iin = 0;
+      while (iin < PNG_MAX_ERROR_TEXT-1 && error_message[iin] != '\0')
+         buffer[iout++] = error_message[iin++];
+
+      /* iin < PNG_MAX_ERROR_TEXT, so the following is safe: */
+      buffer[iout] = '\0';
    }
 }
 #endif /* PNG_WARNINGS_SUPPORTED || PNG_ERROR_TEXT_SUPPORTED */
@@ -272,7 +492,7 @@ png_set_longjmp_fn(png_structp png_ptr, png_longjmp_ptr longjmp_fn,
       return NULL;
 
    png_ptr->longjmp_fn = longjmp_fn;
-   return &png_ptr->png_jmpbuf;
+   return &png_ptr->longjmp_buffer;
 }
 #endif
 
@@ -287,7 +507,8 @@ png_default_error,(png_structp png_ptr, png_const_charp error_message),
 {
 #ifdef PNG_CONSOLE_IO_SUPPORTED
 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
-   if (*error_message == PNG_LITERAL_SHARP)
+   /* Check on NULL only added in 1.5.4 */
+   if (error_message != NULL && *error_message == PNG_LITERAL_SHARP)
    {
       /* Strip "#nnnn " from beginning of error message. */
       int offset;
@@ -317,11 +538,11 @@ png_default_error,(png_structp png_ptr, png_const_charp error_message),
    else
 #endif
    {
-      fprintf(stderr, "libpng error: %s", error_message);
+      fprintf(stderr, "libpng error: %s", error_message ? error_message :
+         "undefined");
       fprintf(stderr, PNG_STRING_NEWLINE);
    }
-#endif
+#else
-#ifndef PNG_CONSOLE_IO_SUPPORTED
    PNG_UNUSED(error_message) /* Make compiler happy */
 #endif
    png_longjmp(png_ptr, 1);
@@ -335,13 +556,13 @@ png_longjmp,(png_structp png_ptr, int val),PNG_NORETURN)
    {
 #  ifdef USE_FAR_KEYWORD
       {
-         jmp_buf png_jmpbuf;
+         jmp_buf tmp_jmpbuf;
-         png_memcpy(png_jmpbuf, png_ptr->png_jmpbuf, png_sizeof(jmp_buf));
+         png_memcpy(tmp_jmpbuf, png_ptr->longjmp_buffer, png_sizeof(jmp_buf));
-         png_ptr->longjmp_fn(png_jmpbuf, val);
+         png_ptr->longjmp_fn(tmp_jmpbuf, val);
       }
 
 #  else
-   png_ptr->longjmp_fn(png_ptr->png_jmpbuf, val);
+   png_ptr->longjmp_fn(png_ptr->longjmp_buffer, val);
 #  endif
    }
 #endif
@@ -403,7 +624,7 @@ png_default_warning(png_structp png_ptr, png_const_charp warning_message)
 /* This function is called when the application wants to use another method
  * of handling errors and warnings.  Note that the error function MUST NOT
  * return to the calling routine or serious problems will occur.  The return
- * method used in the default routine calls longjmp(png_ptr->png_jmpbuf, 1)
+ * method used in the default routine calls longjmp(png_ptr->longjmp_buffer, 1)
  */
 void PNGAPI
 png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
@@ -414,7 +635,11 @@ png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
 
    png_ptr->error_ptr = error_ptr;
    png_ptr->error_fn = error_fn;
+#ifdef PNG_WARNINGS_SUPPORTED
    png_ptr->warning_fn = warning_fn;
+#else
+   PNG_UNUSED(warning_fn)
+#endif
 }
 
 

GRRLIB/lib/png/pnginfo.h

@@ -138,7 +138,6 @@ defined(PNG_READ_BACKGROUND_SUPPORTED)
     * single color specified that should be treated as fully transparent.
     * Data is valid if (valid & PNG_INFO_tRNS) is non-zero.
     */
-   png_bytep trans;    /* alpha values for paletted image */
    png_bytep trans_alpha;    /* alpha values for paletted image */
    png_color_16 trans_color; /* transparent color for non-palette image */
 #endif

GRRLIB/lib/png/pnglibconf.h

@@ -1,8 +1,8 @@
 /* pnglibconf.h - library build configuration */
 
-/* libpng version 1.5.0 - January 6, 2011 */
+/* libpng version 1.5.3 - July 7, 2011 */
 
-/* Copyright (c) 1998-2010 Glenn Randers-Pehrson */
+/* Copyright (c) 1998-2011 Glenn Randers-Pehrson */
 
 /* This code is released under the libpng license. */
 /* For conditions of distribution and use, see the disclaimer */
@@ -44,35 +44,37 @@
 #define PNG_ALIGN_MEMORY_SUPPORTED
 #define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
 #define PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+#define PNG_BUILD_GRAYSCALE_PALETTE_SUPPORTED
 #define PNG_USER_LIMITS_SUPPORTED
 #define PNG_FIXED_POINT_SUPPORTED
 /*#undef PNG_ERROR_NUMBERS_SUPPORTED*/
 #define PNG_ERROR_TEXT_SUPPORTED
 #define PNG_READ_SUPPORTED
-/*#undef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED*/
 #define PNG_BENIGN_ERRORS_SUPPORTED
 #define PNG_SETJMP_SUPPORTED
+#define PNG_TIME_RFC1123_SUPPORTED
 #define PNG_WRITE_FLUSH_SUPPORTED
 #define PNG_MNG_FEATURES_SUPPORTED
 #define PNG_FLOATING_POINT_SUPPORTED
-#define PNG_INCH_CONVERSIONS_SUPPORTED
+#define PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
 #define PNG_STDIO_SUPPORTED
-#define PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
+#define PNG_INCH_CONVERSIONS_SUPPORTED
 #define PNG_USER_MEM_SUPPORTED
+#define PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
 #define PNG_IO_STATE_SUPPORTED
 #define PNG_SET_USER_LIMITS_SUPPORTED
 #define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
 #define PNG_WRITE_INT_FUNCTIONS_SUPPORTED
 #define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
 #define PNG_WRITE_FILTER_SUPPORTED
-#define PNG_SET_CHUNK_CACHE_LIMIT_SUPPORTED
+#define PNG_WRITE_zTXt_SUPPORTED
 #define PNG_WRITE_iCCP_SUPPORTED
 #define PNG_READ_TRANSFORMS_SUPPORTED
-#define PNG_READ_GAMMA_SUPPORTED
+#define PNG_SET_CHUNK_CACHE_LIMIT_SUPPORTED
 #define PNG_READ_bKGD_SUPPORTED
 #define PNG_UNKNOWN_CHUNKS_SUPPORTED
-#define PNG_READ_sCAL_SUPPORTED
 #define PNG_WRITE_hIST_SUPPORTED
+#define PNG_READ_sCAL_SUPPORTED
 #define PNG_READ_OPT_PLTE_SUPPORTED
 #define PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
 #define PNG_WRITE_gAMA_SUPPORTED
@@ -80,20 +82,23 @@
 #define PNG_WRITE_pCAL_SUPPORTED
 #define PNG_READ_INVERT_ALPHA_SUPPORTED
 #define PNG_WRITE_TRANSFORMS_SUPPORTED
+#define PNG_READ_ALPHA_MODE_SUPPORTED
+#define PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
 #define PNG_READ_sBIT_SUPPORTED
 #define PNG_READ_PACK_SUPPORTED
 #define PNG_WRITE_SWAP_SUPPORTED
+#define PNG_WRITE_iTXt_SUPPORTED
 #define PNG_READ_cHRM_SUPPORTED
+#define PNG_READ_STRIP_16_TO_8_SUPPORTED
 #define PNG_WRITE_tIME_SUPPORTED
-#define PNG_READ_INTERLACING_SUPPORTED
-#define PNG_READ_tRNS_SUPPORTED
-#define PNG_WRITE_pHYs_SUPPORTED
-#define PNG_WRITE_INVERT_SUPPORTED
 #define PNG_READ_RGB_TO_GRAY_SUPPORTED
+#define PNG_WRITE_INVERT_SUPPORTED
+#define PNG_WRITE_pHYs_SUPPORTED
+#define PNG_READ_tRNS_SUPPORTED
+#define PNG_READ_INTERLACING_SUPPORTED
 #define PNG_WRITE_sRGB_SUPPORTED
 #define PNG_READ_oFFs_SUPPORTED
 #define PNG_WRITE_FILLER_SUPPORTED
-#define PNG_WRITE_TEXT_SUPPORTED
 #define PNG_WRITE_SHIFT_SUPPORTED
 #define PNG_PROGRESSIVE_READ_SUPPORTED
 #define PNG_READ_SHIFT_SUPPORTED
@@ -101,42 +106,39 @@
 #define PNG_READ_USER_TRANSFORM_SUPPORTED
 #define PNG_READ_INT_FUNCTIONS_SUPPORTED
 #define PNG_READ_USER_CHUNKS_SUPPORTED
-#define PNG_READ_hIST_SUPPORTED
 #define PNG_READ_16BIT_SUPPORTED
+#define PNG_READ_hIST_SUPPORTED
 #define PNG_READ_SWAP_ALPHA_SUPPORTED
 #define PNG_READ_COMPOSITE_NODIV_SUPPORTED
 #define PNG_SEQUENTIAL_READ_SUPPORTED
 #define PNG_READ_BACKGROUND_SUPPORTED
 #define PNG_READ_QUANTIZE_SUPPORTED
-#define PNG_READ_iCCP_SUPPORTED
+#define PNG_READ_zTXt_SUPPORTED
 #define PNG_READ_STRIP_ALPHA_SUPPORTED
+#define PNG_READ_iCCP_SUPPORTED
 #define PNG_READ_PACKSWAP_SUPPORTED
 #define PNG_READ_sRGB_SUPPORTED
-#define PNG_WRITE_tEXt_SUPPORTED
-#define PNG_READ_gAMA_SUPPORTED
 #define PNG_READ_pCAL_SUPPORTED
-#define PNG_READ_EXPAND_SUPPORTED
 #define PNG_WRITE_sPLT_SUPPORTED
 #define PNG_READ_SWAP_SUPPORTED
+#define PNG_READ_iTXt_SUPPORTED
 #define PNG_READ_tIME_SUPPORTED
 #define PNG_READ_pHYs_SUPPORTED
 #define PNG_WRITE_SWAP_ALPHA_SUPPORTED
-#define PNG_TIME_RFC1123_SUPPORTED
+#define PNG_READ_SCALE_16_TO_8_SUPPORTED
-#define PNG_READ_TEXT_SUPPORTED
 #define PNG_WRITE_BGR_SUPPORTED
 #define PNG_USER_CHUNKS_SUPPORTED
 #define PNG_CONSOLE_IO_SUPPORTED
+#define PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
 #define PNG_WRITE_PACK_SUPPORTED
 #define PNG_READ_FILLER_SUPPORTED
 #define PNG_WRITE_bKGD_SUPPORTED
-#define PNG_WRITE_tRNS_SUPPORTED
 #define PNG_READ_sPLT_SUPPORTED
+#define PNG_WRITE_tRNS_SUPPORTED
 #define PNG_WRITE_sCAL_SUPPORTED
 #define PNG_WRITE_oFFs_SUPPORTED
-#define PNG_READ_tEXt_SUPPORTED
 #define PNG_WRITE_sBIT_SUPPORTED
 #define PNG_READ_INVERT_SUPPORTED
-#define PNG_READ_16_TO_8_SUPPORTED
 #define PNG_WRITE_cHRM_SUPPORTED
 #define PNG_16BIT_SUPPORTED
 #define PNG_WRITE_USER_TRANSFORM_SUPPORTED
@@ -144,29 +146,35 @@
 #define PNG_WRITE_PACKSWAP_SUPPORTED
 #define PNG_WRITE_INVERT_ALPHA_SUPPORTED
 #define PNG_sCAL_SUPPORTED
-#define PNG_WRITE_zTXt_SUPPORTED
+#define PNG_READ_GAMMA_SUPPORTED
+#define PNG_USER_TRANSFORM_INFO_SUPPORTED
 #define PNG_sBIT_SUPPORTED
 #define PNG_cHRM_SUPPORTED
 #define PNG_bKGD_SUPPORTED
 #define PNG_tRNS_SUPPORTED
-#define PNG_WRITE_iTXt_SUPPORTED
 #define PNG_oFFs_SUPPORTED
+#define PNG_READ_EXPAND_16_SUPPORTED
 #define PNG_USER_TRANSFORM_PTR_SUPPORTED
+#define PNG_WRITE_TEXT_SUPPORTED
+#define PNG_READ_COMPRESSED_TEXT_SUPPORTED
 #define PNG_hIST_SUPPORTED
+#define PNG_zTXt_SUPPORTED
 #define PNG_iCCP_SUPPORTED
 #define PNG_sRGB_SUPPORTED
-#define PNG_READ_zTXt_SUPPORTED
-#define PNG_gAMA_SUPPORTED
 #define PNG_pCAL_SUPPORTED
 #define PNG_CHECK_cHRM_SUPPORTED
+#define PNG_WRITE_tEXt_SUPPORTED
+#define PNG_READ_gAMA_SUPPORTED
+#define PNG_iTXt_SUPPORTED
 #define PNG_tIME_SUPPORTED
+#define PNG_READ_EXPAND_SUPPORTED
 #define PNG_pHYs_SUPPORTED
-#define PNG_READ_iTXt_SUPPORTED
+#define PNG_READ_TEXT_SUPPORTED
-#define PNG_TEXT_SUPPORTED
 #define PNG_SAVE_INT_32_SUPPORTED
 #define PNG_sPLT_SUPPORTED
+#define PNG_READ_tEXt_SUPPORTED
+#define PNG_gAMA_SUPPORTED
+#define PNG_TEXT_SUPPORTED
 #define PNG_tEXt_SUPPORTED
-#define PNG_zTXt_SUPPORTED
-#define PNG_iTXt_SUPPORTED
 /* end of options */
 #endif /* PNGLCONF_H */

GRRLIB/lib/png/pngmem.c

@@ -1,7 +1,7 @@
 
 /* pngmem.c - stub functions for memory allocation
  *
- * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  * Copyright (c) 1998-2011 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.)
@@ -187,8 +187,9 @@ png_malloc_default,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
             int num_blocks;
             png_uint_32 total_size;
             png_bytep table;
-            int i;
+            int i, mem_level, window_bits;
             png_byte huge * hptr;
+            int window_bits
 
             if (ret != NULL)
             {
@@ -196,14 +197,22 @@ png_malloc_default,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
                ret = NULL;
             }
 
-            if (png_ptr->zlib_window_bits > 14)
+            window_bits =
-               num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
+                png_ptr->zlib_window_bits >= png_ptr->zlib_text_window_bits ?
+                png_ptr->zlib_window_bits : png_ptr->zlib_text_window_bits;
+
+            if (window_bits > 14)
+               num_blocks = (int)(1 << (window_bits - 14));
 
             else
                num_blocks = 1;
 
-            if (png_ptr->zlib_mem_level >= 7)
+            mem_level =
-               num_blocks += (int)(1 << (png_ptr->zlib_mem_level - 7));
+                png_ptr->zlib_mem_level >= png_ptr->zlib_text_mem_level ?
+                png_ptr->zlib_mem_level : png_ptr->zlib_text_mem_level;
+
+            if (mem_level >= 7)
+               num_blocks += (int)(1 << (mem_level - 7));
 
             else
                num_blocks++;
@@ -277,7 +286,7 @@ png_malloc_default,(png_structp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
       {
 #  ifndef PNG_USER_MEM_SUPPORTED
          if ((png_ptr->flags&PNG_FLAG_MALLOC_NULL_MEM_OK) == 0)
-            png_error(png_ptr, "Out of Memory"); /* Note "o" and "M" */
+            png_error(png_ptr, "Out of Memory"); /* Note "O" and "M" */
 
          else
             png_warning(png_ptr, "Out of Memory");

GRRLIB/lib/png/pngpread.c

@@ -1026,8 +1026,10 @@ png_push_process_row(png_structp png_ptr)
 
    png_memcpy(png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1);
 
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
    if (png_ptr->transformations)
       png_do_read_transformations(png_ptr);
+#endif
 
 #ifdef PNG_READ_INTERLACING_SUPPORTED
    /* Blow up interlaced rows to full size */
@@ -1288,7 +1290,7 @@ png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
       {
          PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
          png_error(png_ptr, "Out of place tEXt");
-         /*NOT REACHED*/
+         /* NOT REACHED */
       }
 
 #ifdef PNG_MAX_MALLOC_64K
@@ -1385,7 +1387,7 @@ png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
    {
       PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
       png_error(png_ptr, "Out of place zTXt");
-      /*NOT REACHED*/
+      /* NOT REACHED */
    }
 
 #ifdef PNG_MAX_MALLOC_64K
@@ -1589,7 +1591,7 @@ png_push_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
    {
       PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */
       png_error(png_ptr, "Out of place iTXt");
-      /*NOT REACHED*/
+      /* NOT REACHED */
    }
 
 #ifdef PNG_MAX_MALLOC_64K

GRRLIB/lib/png/pngpriv.h

@@ -6,7 +6,7 @@
  * (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 1.5.2 [March 31, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -25,6 +25,20 @@
 #ifndef PNGPRIV_H
 #define PNGPRIV_H
 
+/* Feature Test Macros.  The following are defined here to ensure that correctly
+ * implemented libraries reveal the APIs libpng needs to build and hide those
+ * that are not needed and potentially damaging to the compilation.
+ *
+ * Feature Test Macros must be defined before any system header is included (see
+ * POSIX 1003.1 2.8.2 "POSIX Symbols."
+ *
+ * These macros only have an effect if the operating system supports either
+ * POSIX 1003.1 or C99, or both.  On other operating systems (particularly
+ * Windows/Visual Studio) there is no effect; the OS specific tests below are
+ * still required (as of 2011-05-02.)
+ */
+#define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
+
 /* This is required for the definition of abort(), used as a last ditch
  * error handler when all else fails.
  */
@@ -101,12 +115,27 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 #  define PNG_ZBUF_SIZE 65536L
 #endif
 
-/* If warnings or errors are turned off the code is disabled
+/* PNG_STATIC is used to mark internal file scope functions if they need to be
- * or redirected here.
+ * accessed for implementation tests (see the code in tests/?*).
  */
-#ifndef PNG_WARNINGS_SUPPORTED
+#ifndef PNG_STATIC
-#  define png_warning(s1,s2) ((void)0)
+#   define PNG_STATIC static
-#  define png_chunk_warning(s1,s2) ((void)0)
+#endif
+
+/* If warnings or errors are turned off the code is disabled or redirected here.
+ * From 1.5.4 functions have been added to allow very limited formatting of
+ * error and warning messages - this code will also be disabled here.
+ */
+#ifdef PNG_WARNINGS_SUPPORTED
+#  define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
+#else
+#  define png_warning(s1,s2) ((void)(s1))
+#  define png_chunk_warning(s1,s2) ((void)(s1))
+#  define png_warning_parameter(p,number,string) ((void)0)
+#  define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
+#  define png_warning_parameter_signed(p,number,format,value) ((void)0)
+#  define png_formatted_warning(pp,p,message) ((void)(pp))
+#  define PNG_WARNING_PARAMETERS(p)
 #endif
 #ifndef PNG_ERROR_TEXT_SUPPORTED
 #  define png_error(s1,s2) png_err(s1)
@@ -200,60 +229,28 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 #  define NOCHECK 0
 #  define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
 #  define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
-#  define png_strcpy  _fstrcpy
-#  define png_strncpy _fstrncpy   /* Added to v 1.2.6 */
 #  define png_strlen  _fstrlen
 #  define png_memcmp  _fmemcmp    /* SJT: added */
 #  define png_memcpy  _fmemcpy
 #  define png_memset  _fmemset
-#  define png_sprintf sprintf
 #else
 #  ifdef _WINDOWS_  /* Favor Windows over C runtime fns */
 #    define CVT_PTR(ptr)         (ptr)
 #    define CVT_PTR_NOCHECK(ptr) (ptr)
-#    define png_strcpy  lstrcpyA
-#    define png_strncpy lstrcpynA
 #    define png_strlen  lstrlenA
 #    define png_memcmp  memcmp
 #    define png_memcpy  CopyMemory
 #    define png_memset  memset
-#    define png_sprintf wsprintfA
 #  else
 #    define CVT_PTR(ptr)         (ptr)
 #    define CVT_PTR_NOCHECK(ptr) (ptr)
-#    define png_strcpy  strcpy
-#    define png_strncpy strncpy     /* Added to v 1.2.6 */
 #    define png_strlen  strlen
 #    define png_memcmp  memcmp      /* SJT: added */
 #    define png_memcpy  memcpy
 #    define png_memset  memset
-#    define png_sprintf sprintf
 #  endif
 #endif
 /* End of memory model/platform independent support */
-
-#ifndef PNG_NO_SNPRINTF
-#  ifdef _MSC_VER
-#    define png_snprintf _snprintf   /* Added to v 1.2.19 */
-#    define png_snprintf2 _snprintf
-#    define png_snprintf6 _snprintf
-#  else
-#    define png_snprintf snprintf   /* Added to v 1.2.19 */
-#    define png_snprintf2 snprintf
-#    define png_snprintf6 snprintf
-#  endif
-#else
-  /* You don't have or don't want to use snprintf().  Caution: Using
-   * sprintf instead of snprintf exposes your application to accidental
-   * or malevolent buffer overflows.  If you don't have snprintf()
-   * as a general rule you should provide one (you can get one from
-   * Portable OpenSSH).
-   */
-#  define png_snprintf(s1,n,fmt,x1) png_sprintf(s1,fmt,x1)
-#  define png_snprintf2(s1,n,fmt,x1,x2) png_sprintf(s1,fmt,x1,x2)
-#  define png_snprintf6(s1,n,fmt,x1,x2,x3,x4,x5,x6) \
-      png_sprintf(s1,fmt,x1,x2,x3,x4,x5,x6)
-#endif
 /* End of 1.5.0beta36 move from pngconf.h */
 
 /* CONSTANTS and UTILITY MACROS
@@ -261,12 +258,14 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
  */
 
 /* Various modes of operation.  Note that after an init, mode is set to
- * zero automatically when the structure is created.
+ * zero automatically when the structure is created.  Three of these
+ * are defined in png.h because they need to be visible to applications
+ * that call png_set_unknown_chunk().
  */
-#define PNG_HAVE_IHDR               0x01
+/* #define PNG_HAVE_IHDR            0x01 (defined in png.h) */
-#define PNG_HAVE_PLTE               0x02
+/* #define PNG_HAVE_PLTE            0x02 (defined in png.h) */
 #define PNG_HAVE_IDAT               0x04
-#define PNG_AFTER_IDAT              0x08 /* Have complete zlib datastream */
+/* #define PNG_AFTER_IDAT           0x08 (defined in png.h) */
 #define PNG_HAVE_IEND               0x10
 #define PNG_HAVE_gAMA               0x20
 #define PNG_HAVE_cHRM               0x40
@@ -286,10 +285,10 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 #define PNG_SWAP_BYTES          0x0010
 #define PNG_INVERT_MONO         0x0020
 #define PNG_QUANTIZE            0x0040
-#define PNG_BACKGROUND          0x0080
+#define PNG_COMPOSE             0x0080     /* Was PNG_BACKGROUND */
 #define PNG_BACKGROUND_EXPAND   0x0100
 #define PNG_EXPAND_16           0x0200     /* Added to libpng 1.5.2 */
-#define PNG_16_TO_8             0x0400
+#define PNG_16_TO_8             0x0400     /* Becomes 'chop' in 1.5.4 */
 #define PNG_RGBA                0x0800
 #define PNG_EXPAND              0x1000
 #define PNG_GAMMA               0x2000
@@ -303,10 +302,10 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 #define PNG_RGB_TO_GRAY_ERR   0x200000L
 #define PNG_RGB_TO_GRAY_WARN  0x400000L
 #define PNG_RGB_TO_GRAY       0x600000L  /* two bits, RGB_TO_GRAY_ERR|WARN */
-                       /*     0x800000L     Unused */
+#define PNG_ENCODE_ALPHA      0x800000L  /* Added to libpng-1.5.4 */
 #define PNG_ADD_ALPHA         0x1000000L  /* Added to libpng-1.2.7 */
 #define PNG_EXPAND_tRNS       0x2000000L  /* Added to libpng-1.2.9 */
-                       /*   0x4000000L  unused */
+#define PNG_SCALE_16_TO_8     0x4000000L  /* Added to libpng-1.5.4 */
                        /*   0x8000000L  unused */
                        /*  0x10000000L  unused */
                        /*  0x20000000L  unused */
@@ -333,9 +332,9 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
 #define PNG_FLAG_CRC_ANCILLARY_NOWARN     0x0200
 #define PNG_FLAG_CRC_CRITICAL_USE         0x0400
 #define PNG_FLAG_CRC_CRITICAL_IGNORE      0x0800
-                                /*        0x1000  unused */
+#define PNG_FLAG_ASSUME_sRGB              0x1000  /* Added to libpng-1.5.4 */
-                                /*        0x2000  unused */
+#define PNG_FLAG_OPTIMIZE_ALPHA           0x2000  /* Added to libpng-1.5.4 */
-                                /*        0x4000  unused */
+#define PNG_FLAG_DETECT_UNINITIALIZED     0x4000  /* Added to libpng-1.5.4 */
 #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS      0x8000L
 #define PNG_FLAG_KEEP_UNSAFE_CHUNKS       0x10000L
 #define PNG_FLAG_LIBRARY_MISMATCH         0x20000L
@@ -345,13 +344,13 @@ typedef PNG_CONST png_uint_16p FAR * png_const_uint_16pp;
                                   /*      0x200000L  unused */
                                   /*      0x400000L  unused */
 #define PNG_FLAG_BENIGN_ERRORS_WARN       0x800000L  /* Added to libpng-1.4.0 */
-                                  /*     0x1000000L  unused */
+#define PNG_FLAG_ZTXT_CUSTOM_STRATEGY    0x1000000L  /* 5 lines added */
-                                  /*     0x2000000L  unused */
+#define PNG_FLAG_ZTXT_CUSTOM_LEVEL       0x2000000L  /* to libpng-1.5.4 */
-                                  /*     0x4000000L  unused */
+#define PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL   0x4000000L
-                                  /*     0x8000000L  unused */
+#define PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS 0x8000000L
-                                  /*    0x10000000L  unused */
+#define PNG_FLAG_ZTXT_CUSTOM_METHOD      0x10000000L
-                                  /*    0x20000000L  unused */
+                                  /*     0x20000000L  unused */
-                                  /*    0x40000000L  unused */
+                                  /*     0x40000000L  unused */
 
 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
                                      PNG_FLAG_CRC_ANCILLARY_NOWARN)
@@ -460,6 +459,11 @@ PNG_EXTERN png_fixed_point png_fixed PNGARG((png_structp png_ptr, double fp,
 #define PNG_tRNS PNG_CONST png_byte png_tRNS[5] = {116,  82,  78,  83, '\0'}
 #define PNG_zTXt PNG_CONST png_byte png_zTXt[5] = {122,  84,  88, 116, '\0'}
 
+/* Gamma values (new at libpng-1.5.4): */
+#define PNG_GAMMA_MAC_OLD 151724  /* Assume '1.8' is really 2.2/1.45! */
+#define PNG_GAMMA_MAC_INVERSE 65909
+#define PNG_GAMMA_sRGB_INVERSE 45455
+
 
 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
 #ifdef __cplusplus
@@ -472,6 +476,12 @@ extern "C" {
  * be found in the files where the functions are located.
  */
 
+/* Check the user version string for compatibility, returns false if the version
+ * numbers aren't compatible.
+ */
+PNG_EXTERN int png_user_version_check(png_structp png_ptr,
+   png_const_charp user_png_ver);
+
 /* Allocate memory for an internal libpng struct */
 PNG_EXTERN PNG_FUNCTION(png_voidp,png_create_struct,PNGARG((int type)),
    PNG_ALLOCATED);
@@ -540,8 +550,7 @@ PNG_EXTERN void png_crc_read PNGARG((png_structp png_ptr, png_bytep buf,
     png_size_t length));
 
 /* Decompress data in a chunk that uses compression */
-#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
+#if defined(PNG_READ_COMPRESSED_TEXT_SUPPORTED)
-    defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
 PNG_EXTERN void png_decompress_chunk PNGARG((png_structp png_ptr,
     int comp_type, png_size_t chunklength, png_size_t prefix_length,
     png_size_t *data_length));
@@ -644,6 +653,7 @@ PNG_EXTERN void png_write_hIST PNGARG((png_structp png_ptr,
     png_const_uint_16p hist, int num_hist));
 #endif
 
+/* Chunks that have keywords */
 #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
     defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
 PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
@@ -734,17 +744,17 @@ PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
 PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
     png_row_infop row_info));
 
-/* Write out the filtered row. */
-PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
-    png_bytep filtered_row));
 /* Finish a row while reading, dealing with interlacing passes, etc. */
 PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
 
 /* Initialize the row buffers, etc. */
 PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
 /* Optional call to update the users info structure */
 PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
     png_infop info_ptr));
+#endif
 
 /* These are the functions that do the transformations */
 #ifdef PNG_READ_FILLER_SUPPORTED
@@ -816,7 +826,12 @@ PNG_EXTERN void png_do_invert PNGARG((png_row_infop row_info,
     png_bytep row));
 #endif
 
-#ifdef PNG_READ_16_TO_8_SUPPORTED
+#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+PNG_EXTERN void png_do_scale_16_to_8 PNGARG((png_row_infop row_info,
+    png_bytep row));
+#endif
+
+#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
 PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info,
     png_bytep row));
 #endif
@@ -847,26 +862,20 @@ PNG_EXTERN void png_do_shift PNGARG((png_row_infop row_info,
     png_bytep row, png_const_color_8p bit_depth));
 #endif
 
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
-#  ifdef PNG_READ_GAMMA_SUPPORTED
+    defined(PNG_READ_ALPHA_MODE_SUPPORTED)
-PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info,
+PNG_EXTERN void png_do_compose PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_color_16p trans_color,
+    png_bytep row, png_structp png_ptr));
-    png_const_color_16p background, png_const_color_16p background_1,
-    png_const_bytep gamma_table, png_const_bytep gamma_from_1,
-    png_const_bytep gamma_to_1, png_const_uint_16pp gamma_16,
-    png_const_uint_16pp gamma_16_from_1, png_const_uint_16pp gamma_16_to_1,
-    int gamma_shift));
-#  else
-PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_color_16p trans_color,
-    png_const_color_16p background));
-#  endif
 #endif
 
 #ifdef PNG_READ_GAMMA_SUPPORTED
 PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info,
-    png_bytep row, png_const_bytep gamma_table,
+    png_bytep row, png_structp png_ptr));
-    png_const_uint_16pp gamma_16_table, int gamma_shift));
+#endif
+
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+PNG_EXTERN void png_do_encode_alpha PNGARG((png_row_infop row_info,
+   png_bytep row, png_structp png_ptr));
 #endif
 
 #ifdef PNG_READ_EXPAND_SUPPORTED
@@ -986,10 +995,16 @@ PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
     png_const_bytep chunk_name));
 
 /* Handle the transformations for reading and writing */
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
 PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
+#endif
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
 PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
+#endif
 
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
 PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
+#endif
 
 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
 PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
@@ -1086,6 +1101,76 @@ PNG_EXTERN PNG_FUNCTION(void, png_fixed_error, (png_structp png_ptr,
    png_const_charp name),PNG_NORETURN);
 #endif
 
+/* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
+ * the end.  Always leaves the buffer nul terminated.  Never errors out (and
+ * there is no error code.)
+ */
+PNG_EXTERN size_t png_safecat(png_charp buffer, size_t bufsize, size_t pos,
+    png_const_charp string);
+
+/* Various internal functions to handle formatted warning messages, currently
+ * only implemented for warnings.
+ */
+#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
+/* Utility to dump an unsigned value into a buffer, given a start pointer and
+ * and end pointer (which should point just *beyond* the end of the buffer!)
+ * Returns the pointer to the start of the formatted string.  This utility only
+ * does unsigned values.
+ */
+PNG_EXTERN png_charp png_format_number(png_const_charp start, png_charp end,
+   int format, png_alloc_size_t number);
+
+/* Convenience macro that takes an array: */
+#define PNG_FORMAT_NUMBER(buffer,format,number) \
+   png_format_number(buffer, buffer + (sizeof buffer), format, number)
+
+/* Suggested size for a number buffer (enough for 64 bits and a sign!) */
+#define PNG_NUMBER_BUFFER_SIZE 24
+
+/* These are the integer formats currently supported, the name is formed from
+ * the standard printf(3) format string.
+ */
+#define PNG_NUMBER_FORMAT_u     1 /* chose unsigned API! */
+#define PNG_NUMBER_FORMAT_02u   2
+#define PNG_NUMBER_FORMAT_d     1 /* chose signed API! */
+#define PNG_NUMBER_FORMAT_02d   2
+#define PNG_NUMBER_FORMAT_x     3
+#define PNG_NUMBER_FORMAT_02x   4
+#define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
+#endif
+
+#ifdef PNG_WARNINGS_SUPPORTED
+/* New defines and members adding in libpng-1.5.4 */
+#  define PNG_WARNING_PARAMETER_SIZE 32
+#  define PNG_WARNING_PARAMETER_COUNT 8
+
+/* An l-value of this type has to be passed to the APIs below to cache the
+ * values of the parameters to a formatted warning message.
+ */
+typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
+   PNG_WARNING_PARAMETER_SIZE];
+
+PNG_EXTERN void png_warning_parameter(png_warning_parameters p, int number,
+    png_const_charp string);
+    /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
+     * including the trailing '\0'.
+     */
+PNG_EXTERN void png_warning_parameter_unsigned(png_warning_parameters p,
+    int number, int format, png_alloc_size_t value);
+    /* Use png_alloc_size_t because it is an unsigned type as big as any we
+     * need to output.  Use the following for a signed value.
+     */
+PNG_EXTERN void png_warning_parameter_signed(png_warning_parameters p,
+    int number, int format, png_int_32 value);
+
+PNG_EXTERN void png_formatted_warning(png_structp png_ptr,
+    png_warning_parameters p, png_const_charp message);
+    /* 'message' follows the X/Open approach of using @1, @2 to insert
+     * parameters previously supplied using the above functions.  Errors in
+     * specifying the paramters will simple result in garbage substitutions.
+     */
+#endif
+
 /* ASCII to FP interfaces, currently only implemented if sCAL
  * support is required.
  */
@@ -1148,8 +1233,18 @@ PNG_EXTERN void png_ascii_from_fixed PNGARG((png_structp png_ptr,
 #define PNG_FP_SAW_DOT   16  /* Saw a dot in current state */
 #define PNG_FP_SAW_E     32  /* Saw an E (or e) in current state */
 #define PNG_FP_SAW_ANY   60  /* Saw any of the above 4 */
+
+/* These three values don't affect the parser.  They are set but not used.
+ */
 #define PNG_FP_WAS_VALID 64  /* Preceding substring is a valid fp number */
-#define PNG_FP_INVALID  128  /* Available for callers as a distinct value */
+#define PNG_FP_NEGATIVE 128  /* A negative number, including "-0" */
+#define PNG_FP_NONZERO  256  /* A non-zero value */
+#define PNG_FP_STICKY   448  /* The above three flags */
+
+/* This is available for the caller to store in 'state' if required.  Do not
+ * call the parser after setting it (the parser sometimes clears it.)
+ */
+#define PNG_FP_INVALID  512  /* Available for callers as a distinct value */
 
 /* Result codes for the parser (boolean - true meants ok, false means
  * not ok yet.)
@@ -1157,6 +1252,20 @@ PNG_EXTERN void png_ascii_from_fixed PNGARG((png_structp png_ptr,
 #define PNG_FP_MAYBE      0  /* The number may be valid in the future */
 #define PNG_FP_OK         1  /* The number is valid */
 
+/* Tests on the sticky non-zero and negative flags.  To pass these checks
+ * the state must also indicate that the whole number is valid - this is
+ * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
+ * is equivalent to PNG_FP_OK above.)
+ */
+#define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
+   /* NZ_MASK: the string is valid and a non-zero negative value */
+#define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
+   /* Z MASK: the string is valid and a non-zero value. */
+   /* PNG_FP_SAW_DIGIT: the string is valid. */
+#define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
+#define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
+#define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
+ 
 /* The actual parser.  This can be called repeatedly, it updates
  * the index into the string and the state variable (which must
  * be initialzed to 0).  It returns a result code, as above.  There
@@ -1176,7 +1285,10 @@ PNG_EXTERN int png_check_fp_number PNGARG((png_const_charp string,
     png_size_t size, int *statep, png_size_tp whereami));
 
 /* This is the same but it checks a complete string and returns true
- * only if it just contains a floating point number.
+ * only if it just contains a floating point number.  As of 1.5.4 this
+ * function also returns the state at the end of parsing the number if
+ * it was valid (otherwise it returns 0.)  This can be used for testing
+ * for negative or zero values using the sticky flag.
  */
 PNG_EXTERN int png_check_fp_string PNGARG((png_const_charp string,
     png_size_t size));

GRRLIB/lib/png/pngread.c

@@ -1,7 +1,7 @@
 
 /* pngread.c - read a PNG file
  *
- * Last changed in libpng 1.5.2 [March 31, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  * Copyright (c) 1998-2011 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.)
@@ -47,12 +47,10 @@ png_create_read_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
 
 #ifdef PNG_SETJMP_SUPPORTED
 #ifdef USE_FAR_KEYWORD
-   jmp_buf png_jmpbuf;
+   jmp_buf tmp_jmpbuf;
 #endif
 #endif
 
-   int i;
-
    png_debug(1, "in png_create_read_struct");
 
 #ifdef PNG_USER_MEM_SUPPORTED
@@ -85,13 +83,13 @@ png_create_read_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
    encounter a png_error() will longjmp here.  Since the jmpbuf is
    then meaningless we abort instead of returning. */
 #ifdef USE_FAR_KEYWORD
-   if (setjmp(png_jmpbuf))
+   if (setjmp(tmp_jmpbuf))
 #else
    if (setjmp(png_jmpbuf(png_ptr))) /* Sets longjmp to match setjmp */
 #endif
       PNG_ABORT();
 #ifdef USE_FAR_KEYWORD
-   png_memcpy(png_jmpbuf(png_ptr), png_jmpbuf, png_sizeof(jmp_buf));
+   png_memcpy(png_jmpbuf(png_ptr), tmp_jmpbuf, png_sizeof(jmp_buf));
 #endif
 #endif /* PNG_SETJMP_SUPPORTED */
 
@@ -101,54 +99,9 @@ png_create_read_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
 
    png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
 
-   if (user_png_ver)
+   /* Call the general version checker (shared with read and write code): */
-   {
+   if (!png_user_version_check(png_ptr, user_png_ver))
-      i = 0;
+      png_cleanup_needed = 1;
-
-      do
-      {
-         if (user_png_ver[i] != png_libpng_ver[i])
-            png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
-      } while (png_libpng_ver[i++]);
-   }
-
-   else
-      png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
-
-
-   if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
-   {
-     /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
-      * we must recompile any applications that use any older library version.
-      * For versions after libpng 1.0, we will be compatible, so we need
-      * only check the first digit.
-      */
-      if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
-          (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
-          (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
-      {
-#ifdef PNG_CONSOLE_IO_SUPPORTED
-         char msg[80];
-         if (user_png_ver)
-         {
-            png_snprintf2(msg, 80,
-                "Application built with libpng-%.20s"
-                " but running with %.20s",
-                user_png_ver,
-                png_libpng_ver);
-            png_warning(png_ptr, msg);
-         }
-#else
-         png_warning(png_ptr,
-             "Incompatible libpng version in application and library");
-#endif
-#ifdef PNG_ERROR_NUMBERS_SUPPORTED
-         png_ptr->flags = 0;
-#endif
-
-         png_cleanup_needed = 1;
-      }
-   }
 
    if (!png_cleanup_needed)
    {
@@ -457,7 +410,11 @@ png_read_update_info(png_structp png_ptr, png_infop info_ptr)
           "Ignoring extra png_read_update_info() call;"
           " row buffer not reallocated");
 
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
    png_read_transform_info(png_ptr, info_ptr);
+#else
+   PNG_UNUSED(info_ptr)
+#endif
 }
 
 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
@@ -704,8 +661,10 @@ png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
 #endif
 
 
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
    if (png_ptr->transformations)
       png_do_read_transformations(png_ptr);
+#endif
 
 #ifdef PNG_READ_INTERLACING_SUPPORTED
    /* Blow up interlaced rows to full size */
@@ -1163,7 +1122,9 @@ png_read_destroy(png_structp png_ptr, png_infop info_ptr,
    jmp_buf tmp_jmp;
 #endif
    png_error_ptr error_fn;
+#ifdef PNG_WARNINGS_SUPPORTED
    png_error_ptr warning_fn;
+#endif
    png_voidp error_ptr;
 #ifdef PNG_USER_MEM_SUPPORTED
    png_free_ptr free_fn;
@@ -1249,10 +1210,6 @@ png_read_destroy(png_structp png_ptr, png_infop info_ptr,
 #endif
 #endif
 
-#ifdef PNG_TIME_RFC1123_SUPPORTED
-   png_free(png_ptr, png_ptr->time_buffer);
-#endif
-
    inflateEnd(&png_ptr->zstream);
 
 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
@@ -1269,11 +1226,13 @@ png_read_destroy(png_structp png_ptr, png_infop info_ptr,
     * being used again.
     */
 #ifdef PNG_SETJMP_SUPPORTED
-   png_memcpy(tmp_jmp, png_ptr->png_jmpbuf, png_sizeof(jmp_buf));
+   png_memcpy(tmp_jmp, png_ptr->longjmp_buffer, png_sizeof(jmp_buf));
 #endif
 
    error_fn = png_ptr->error_fn;
+#ifdef PNG_WARNINGS_SUPPORTED
    warning_fn = png_ptr->warning_fn;
+#endif
    error_ptr = png_ptr->error_ptr;
 #ifdef PNG_USER_MEM_SUPPORTED
    free_fn = png_ptr->free_fn;
@@ -1282,14 +1241,16 @@ png_read_destroy(png_structp png_ptr, png_infop info_ptr,
    png_memset(png_ptr, 0, png_sizeof(png_struct));
 
    png_ptr->error_fn = error_fn;
+#ifdef PNG_WARNINGS_SUPPORTED
    png_ptr->warning_fn = warning_fn;
+#endif
    png_ptr->error_ptr = error_ptr;
 #ifdef PNG_USER_MEM_SUPPORTED
    png_ptr->free_fn = free_fn;
 #endif
 
 #ifdef PNG_SETJMP_SUPPORTED
-   png_memcpy(png_ptr->png_jmpbuf, tmp_jmp, png_sizeof(jmp_buf));
+   png_memcpy(png_ptr->longjmp_buffer, tmp_jmp, png_sizeof(jmp_buf));
 #endif
 
 }
@@ -1325,8 +1286,22 @@ png_read_png(png_structp png_ptr, png_infop info_ptr,
 
    /* -------------- image transformations start here ------------------- */
 
-#ifdef PNG_READ_16_TO_8_SUPPORTED
+#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-   /* Tell libpng to strip 16 bit/color files down to 8 bits per color.
+   /* Tell libpng to strip 16-bit/color files down to 8 bits per color.
+    */
+   if (transforms & PNG_TRANSFORM_SCALE_16)
+   {
+     /* Added at libpng-1.5.4. "strip_16" produces the same result that it
+      * did in earlier versions, while "scale_16" is now more accurate.
+      */
+      png_set_scale_16(png_ptr);
+   }
+#endif
+
+#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
+   /* If both SCALE and STRIP are required pngrtran will effectively cancel the
+    * latter by doing SCALE first.  This is ok and allows apps not to check for
+    * which is supported to get the right answer.
     */
    if (transforms & PNG_TRANSFORM_STRIP_16)
       png_set_strip_16(png_ptr);
@@ -1407,7 +1382,7 @@ png_read_png(png_structp png_ptr, png_infop info_ptr,
 #endif
 
 #ifdef PNG_READ_SWAP_SUPPORTED
-   /* Swap bytes of 16 bit files to least significant byte first */
+   /* Swap bytes of 16-bit files to least significant byte first */
    if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
       png_set_swap(png_ptr);
 #endif
@@ -1426,6 +1401,12 @@ png_read_png(png_structp png_ptr, png_infop info_ptr,
       png_set_gray_to_rgb(png_ptr);
 #endif
 
+/* Added at libpng-1.5.4 */
+#ifdef PNG_READ_EXPAND_16_SUPPORTED
+   if (transforms & PNG_TRANSFORM_EXPAND_16)
+      png_set_expand_16(png_ptr);
+#endif
+
    /* We don't handle adding filler bytes */
 
    /* We use png_read_image and rely on that for interlace handling, but we also

GRRLIB/lib/png/pngrutil.c

@@ -1,7 +1,7 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * Last changed in libpng 1.5.2 [March 31, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  * Copyright (c) 1998-2011 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.)
@@ -278,8 +278,7 @@ png_crc_error(png_structp png_ptr)
       return (0);
 }
 
-#if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) || \
+#ifdef PNG_READ_COMPRESSED_TEXT_SUPPORTED
-    defined(PNG_READ_iCCP_SUPPORTED)
 static png_size_t
 png_inflate(png_structp png_ptr, png_bytep data, png_size_t size,
     png_bytep output, png_size_t output_size)
@@ -370,41 +369,31 @@ png_inflate(png_structp png_ptr, png_bytep data, png_size_t size,
        * and the error message is dumped into the uncompressed
        * buffer if available.
        */
+#     ifdef PNG_WARNINGS_SUPPORTED
       {
-         PNG_CONST char *msg;
+         png_const_charp msg;
-#ifdef PNG_CONSOLE_IO_SUPPORTED
+
-         char umsg[52];
-#endif
          if (png_ptr->zstream.msg != 0)
             msg = png_ptr->zstream.msg;
 
-         else
+         else switch (ret)
          {
-#ifdef PNG_CONSOLE_IO_SUPPORTED
+            case Z_BUF_ERROR:
-            switch (ret)
+               msg = "Buffer error in compressed datastream";
-            {
+               break;
-               case Z_BUF_ERROR:
-                  msg = "Buffer error in compressed datastream in %s chunk";
-                  break;
 
-               case Z_DATA_ERROR:
+            case Z_DATA_ERROR:
-                  msg = "Data error in compressed datastream in %s chunk";
+               msg = "Data error in compressed datastream";
-                  break;
+               break;
 
-               default:
+            default:
-                  msg = "Incomplete compressed datastream in %s chunk";
+               msg = "Incomplete compressed datastream";
-                  break;
+               break;
-            }
-
-            png_snprintf(umsg, sizeof umsg, msg, png_ptr->chunk_name);
-            msg = umsg;
-#else
-            msg = "Damaged compressed datastream in chunk other than IDAT";
-#endif
          }
 
-         png_warning(png_ptr, msg);
+         png_chunk_warning(png_ptr, msg);
       }
+#     endif
 
       /* 0 means an error - notice that this code simply ignores
        * zero length compressed chunks as a result.
@@ -438,8 +427,8 @@ png_decompress_chunk(png_structp png_ptr, int comp_type,
       png_size_t expanded_size = png_inflate(png_ptr,
           (png_bytep)(png_ptr->chunkdata + prefix_size),
           chunklength - prefix_size,
-          0,            /*output*/
+          0,            /* output */
-          0);           /*output size*/
+          0);           /* output size */
 
       /* Now check the limits on this chunk - if the limit fails the
        * compressed data will be removed, the prefix will remain.
@@ -500,15 +489,9 @@ png_decompress_chunk(png_structp png_ptr, int comp_type,
 
    else /* if (comp_type != PNG_COMPRESSION_TYPE_BASE) */
    {
-#ifdef PNG_STDIO_SUPPORTED
+      PNG_WARNING_PARAMETERS(p)
-      char umsg[50];
+      png_warning_parameter_signed(p, 1, PNG_NUMBER_FORMAT_d, comp_type);
-
+      png_formatted_warning(png_ptr, p, "Unknown zTXt compression type @1");
-      png_snprintf(umsg, sizeof umsg,
-          "Unknown zTXt compression type %d", comp_type);
-      png_warning(png_ptr, umsg);
-#else
-      png_warning(png_ptr, "Unknown zTXt compression type");
-#endif
 
       /* The recovery is to simply drop the data. */
    }
@@ -536,7 +519,7 @@ png_decompress_chunk(png_structp png_ptr, int comp_type,
 
    *newlength = prefix_size;
 }
-#endif
+#endif /* PNG_READ_COMPRESSED_TEXT_SUPPORTED */
 
 /* Read and check the IDHR chunk */
 void /* PRIVATE */
@@ -846,12 +829,10 @@ png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    {
       if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))
       {
-         png_warning(png_ptr,
+         PNG_WARNING_PARAMETERS(p)
-             "Ignoring incorrect gAMA value when sRGB is also present");
+         png_warning_parameter_signed(p, 1, PNG_NUMBER_FORMAT_fixed, igamma);
-
+         png_formatted_warning(png_ptr, p,
-#    ifdef PNG_CONSOLE_IO_SUPPORTED
+             "Ignoring incorrect gAMA value @1 when sRGB is also present");
-         fprintf(stderr, "gamma = (%d/100000)", (int)igamma);
-#    endif
          return;
       }
    }
@@ -1020,21 +1001,52 @@ png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
           PNG_OUT_OF_RANGE(x_blue,  15000,  1000) ||
           PNG_OUT_OF_RANGE(y_blue,   6000,  1000))
       {
-         png_warning(png_ptr,
+         PNG_WARNING_PARAMETERS(p)
-             "Ignoring incorrect cHRM value when sRGB is also present");
 
-#ifdef PNG_CONSOLE_IO_SUPPORTED
+         png_warning_parameter_signed(p, 1, PNG_NUMBER_FORMAT_fixed, x_white);
-         fprintf(stderr, "wx=%d, wy=%d, rx=%d, ry=%d\n",
+         png_warning_parameter_signed(p, 2, PNG_NUMBER_FORMAT_fixed, y_white);
-             x_white, y_white, x_red, y_red);
+         png_warning_parameter_signed(p, 3, PNG_NUMBER_FORMAT_fixed, x_red);
+         png_warning_parameter_signed(p, 4, PNG_NUMBER_FORMAT_fixed, y_red);
+         png_warning_parameter_signed(p, 5, PNG_NUMBER_FORMAT_fixed, x_green);
+         png_warning_parameter_signed(p, 6, PNG_NUMBER_FORMAT_fixed, y_green);
+         png_warning_parameter_signed(p, 7, PNG_NUMBER_FORMAT_fixed, x_blue);
+         png_warning_parameter_signed(p, 8, PNG_NUMBER_FORMAT_fixed, y_blue);
 
-         fprintf(stderr, "gx=%d, gy=%d, bx=%d, by=%d\n",
+         png_formatted_warning(png_ptr, p,
-             x_green, y_green, x_blue, y_blue);
+             "Ignoring incorrect cHRM white(@1,@2) r(@3,@4)g(@5,@6)b(@7,@8) "
-#endif /* PNG_CONSOLE_IO_SUPPORTED */
+             "when sRGB is also present");
       }
       return;
    }
 #endif /* PNG_READ_sRGB_SUPPORTED */
 
+#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
+   /* Store the _white values as default coefficients for the rgb to gray
+    * operation if it is supported.
+    */
+   if ((png_ptr->transformations & PNG_RGB_TO_GRAY) == 0)
+   {
+      /* png_set_background has not been called, the coefficients must be in
+       * range for the following to work without overflow.
+       */
+      if (y_red <= (1<<17) && y_green <= (1<<17) && y_blue <= (1<<17))
+      {
+         /* The y values are chromaticities: Y/X+Y+Z, the weights for the gray
+          * transformation are simply the normalized Y values for red, green and
+          * blue scaled by 32768.
+          */
+         png_uint_32 w = y_red + y_green + y_blue;
+
+         png_ptr->rgb_to_gray_red_coeff   = (png_uint_16)(((png_uint_32)y_red *
+            32768)/w);
+         png_ptr->rgb_to_gray_green_coeff = (png_uint_16)(((png_uint_32)y_green
+            * 32768)/w);
+         png_ptr->rgb_to_gray_blue_coeff  = (png_uint_16)(((png_uint_32)y_blue *
+            32768)/w);
+      }
+   }
+#endif
+
    png_set_cHRM_fixed(png_ptr, info_ptr, x_white, y_white, x_red, y_red,
       x_green, y_green, x_blue, y_blue);
 }
@@ -1096,11 +1108,13 @@ png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    {
       if (PNG_OUT_OF_RANGE(info_ptr->gamma, 45500L, 500))
       {
-         png_warning(png_ptr,
+         PNG_WARNING_PARAMETERS(p)
-             "Ignoring incorrect gAMA value when sRGB is also present");
+
-#ifdef PNG_CONSOLE_IO_SUPPORTED
+         png_warning_parameter_signed(p, 1, PNG_NUMBER_FORMAT_fixed,
-         fprintf(stderr, "incorrect gamma=(%d/100000)\n", info_ptr->gamma);
+            info_ptr->gamma);
-#endif
+
+         png_formatted_warning(png_ptr, p,
+             "Ignoring incorrect gAMA value @1 when sRGB is also present");
       }
    }
 #endif /* PNG_READ_gAMA_SUPPORTED */
@@ -1240,23 +1254,15 @@ png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    /* And the following guarantees that profile_size == profile_length. */
    if (profile_size > profile_length)
    {
+      PNG_WARNING_PARAMETERS(p)
+
       png_free(png_ptr, png_ptr->chunkdata);
       png_ptr->chunkdata = NULL;
-#ifdef PNG_STDIO_SUPPORTED
-      {
-         char umsg[80];
 
-         png_snprintf2(umsg, 80,
+      png_warning_parameter_unsigned(p, 1, PNG_NUMBER_FORMAT_u, profile_size);
-             "Ignoring iCCP chunk with declared size = %u "
+      png_warning_parameter_unsigned(p, 2, PNG_NUMBER_FORMAT_u, profile_length);
-              "and actual length = %u",
+      png_formatted_warning(png_ptr, p,
-              (unsigned int) profile_size,
+         "Ignoring iCCP chunk with declared size = @1 and actual length = @2");
-              (unsigned int) profile_length);
-         png_warning(png_ptr, umsg);
-      }
-#else
-      png_warning(png_ptr,
-         "Ignoring iCCP chunk with uncompressed size mismatch");
-#endif
       return;
    }
 
@@ -1565,6 +1571,7 @@ png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_size_t truelen;
    png_byte buf[6];
+   png_color_16 background;
 
    png_debug(1, "in png_handle_bKGD");
 
@@ -1621,7 +1628,7 @@ png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
     */
    if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
    {
-      png_ptr->background.index = buf[0];
+      background.index = buf[0];
 
       if (info_ptr && info_ptr->num_palette)
       {
@@ -1631,33 +1638,36 @@ png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
             return;
          }
 
-         png_ptr->background.red =
+         background.red = (png_uint_16)png_ptr->palette[buf[0]].red;
-             (png_uint_16)png_ptr->palette[buf[0]].red;
+         background.green = (png_uint_16)png_ptr->palette[buf[0]].green;
-
+         background.blue = (png_uint_16)png_ptr->palette[buf[0]].blue;
-         png_ptr->background.green =
-             (png_uint_16)png_ptr->palette[buf[0]].green;
-
-         png_ptr->background.blue =
-             (png_uint_16)png_ptr->palette[buf[0]].blue;
       }
+
+      else
+         background.red = background.green = background.blue = 0;
+
+      background.gray = 0;
    }
 
    else if (!(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) /* GRAY */
    {
-      png_ptr->background.red =
+      background.index = 0;
-      png_ptr->background.green =
+      background.red =
-      png_ptr->background.blue =
+      background.green =
-      png_ptr->background.gray = png_get_uint_16(buf);
+      background.blue =
+      background.gray = png_get_uint_16(buf);
    }
 
    else
    {
-      png_ptr->background.red = png_get_uint_16(buf);
+      background.index = 0;
-      png_ptr->background.green = png_get_uint_16(buf + 2);
+      background.red = png_get_uint_16(buf);
-      png_ptr->background.blue = png_get_uint_16(buf + 4);
+      background.green = png_get_uint_16(buf + 2);
+      background.blue = png_get_uint_16(buf + 4);
+      background.gray = 0;
    }
 
-   png_set_bKGD(png_ptr, info_ptr, &(png_ptr->background));
+   png_set_bKGD(png_ptr, info_ptr, &background);
 }
 #endif
 
@@ -1982,6 +1992,14 @@ png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
       return;
    }
 
+   /* Need unit type, width, \0, height: minimum 4 bytes */
+   else if (length < 4)
+   {
+      png_warning(png_ptr, "sCAL chunk too short");
+      png_crc_finish(png_ptr, length);
+      return;
+   }
+
    png_debug1(2, "Allocating and reading sCAL chunk data (%u bytes)",
       length + 1);
 
@@ -2017,23 +2035,29 @@ png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    /* Validate the ASCII numbers, need two ASCII numbers separated by
     * a '\0' and they need to fit exactly in the chunk data.
     */
-   i = 0;
+   i = 1;
    state = 0;
 
-   if (png_ptr->chunkdata[1] == 45 /* negative width */ ||
+   if (!png_check_fp_number(png_ptr->chunkdata, slength, &state, &i) ||
-       !png_check_fp_number(png_ptr->chunkdata, slength, &state, &i) ||
        i >= slength || png_ptr->chunkdata[i++] != 0)
       png_warning(png_ptr, "Invalid sCAL chunk ignored: bad width format");
 
+   else if (!PNG_FP_IS_POSITIVE(state))
+      png_warning(png_ptr, "Invalid sCAL chunk ignored: non-positive width");
+
    else
    {
       png_size_t heighti = i;
 
-      if (png_ptr->chunkdata[i] == 45 /* negative height */ ||
+      state = 0;
-          !png_check_fp_number(png_ptr->chunkdata, slength, &state, &i) ||
+      if (!png_check_fp_number(png_ptr->chunkdata, slength, &state, &i) ||
           i != slength)
          png_warning(png_ptr, "Invalid sCAL chunk ignored: bad height format");
 
+      else if (!PNG_FP_IS_POSITIVE(state))
+         png_warning(png_ptr,
+            "Invalid sCAL chunk ignored: non-positive height");
+
       else
          /* This is the (only) success case. */
          png_set_sCAL_s(png_ptr, info_ptr, png_ptr->chunkdata[0],
@@ -2660,6 +2684,14 @@ png_combine_row(png_structp png_ptr, png_bytep row, int mask)
 {
    png_debug(1, "in png_combine_row");
 
+   /* Added in 1.5.4: the row_info should match the information returned by any
+    * call to png_read_update_info at this point.  Do not continue if we got
+    * this wrong.
+    */
+   if (png_ptr->info_rowbytes != 0 && png_ptr->info_rowbytes !=
+          PNG_ROWBYTES(png_ptr->row_info.pixel_depth, png_ptr->width))
+      png_error(png_ptr, "internal row size calculation error");
+
    if (mask == 0xff)
    {
       png_memcpy(row, png_ptr->row_buf + 1,
@@ -3398,7 +3430,9 @@ png_read_start_row(png_structp png_ptr)
 
    png_debug(1, "in png_read_start_row");
    png_ptr->zstream.avail_in = 0;
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
    png_init_read_transformations(png_ptr);
+#endif
 #ifdef PNG_READ_INTERLACING_SUPPORTED
    if (png_ptr->interlaced)
    {

GRRLIB/lib/png/pngset.c

@@ -1,7 +1,7 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  * Copyright (c) 1998-2011 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.)
@@ -94,15 +94,16 @@ png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   /* Previously these values were limited, however they must be
+   /* Changed in libpng-1.5.4 to limit the values to ensure overflow can't
-    * wrong, therefore storing them (and setting PNG_INFO_gAMA)
+    * occur.  Since the fixed point representation is assymetrical it is
-    * must be wrong too.
+    * possible for 1/gamma to overflow the limit of 21474 and this means the
+    * gamma value must be at least 5/100000 and hence at most 20000.0.  For
+    * safety the limits here are a little narrower.  The values are 0.00016 to
+    * 6250.0, which are truely ridiculous gammma values (and will produce
+    * displays that are all black or all white.)
     */
-   if (file_gamma > (png_fixed_point)PNG_UINT_31_MAX)
+   if (file_gamma < 16 || file_gamma > 625000000)
-      png_warning(png_ptr, "Gamma too large, ignored");
+      png_warning(png_ptr, "Out of range gamma value ignored");
-
-   else if (file_gamma <= 0)
-      png_warning(png_ptr, "Negative or zero gamma ignored");
 
    else
    {
@@ -340,12 +341,12 @@ png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,
    if (unit != 1 && unit != 2)
       png_error(png_ptr, "Invalid sCAL unit");
 
-   if (swidth == NULL || (lengthw = png_strlen(swidth)) <= 0 ||
+   if (swidth == NULL || (lengthw = png_strlen(swidth)) == 0 ||
-       swidth[0] == 45 /*'-'*/ || !png_check_fp_string(swidth, lengthw))
+       swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw))
       png_error(png_ptr, "Invalid sCAL width");
 
-   if (sheight == NULL || (lengthh = png_strlen(sheight)) <= 0 ||
+   if (sheight == NULL || (lengthh = png_strlen(sheight)) == 0 ||
-       sheight[0] == 45 /*'-'*/ || !png_check_fp_string(sheight, lengthh))
+       sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh))
       png_error(png_ptr, "Invalid sCAL height");
 
    info_ptr->scal_unit = (png_byte)unit;
@@ -545,7 +546,7 @@ png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
    png_set_sRGB(png_ptr, info_ptr, srgb_intent);
 
 #  ifdef PNG_gAMA_SUPPORTED
-   png_set_gAMA_fixed(png_ptr, info_ptr, 45455L);
+   png_set_gAMA_fixed(png_ptr, info_ptr, PNG_GAMMA_sRGB_INVERSE);
 #  endif
 
 #  ifdef PNG_cHRM_SUPPORTED

GRRLIB/lib/png/pngstruct.h

@@ -5,7 +5,7 @@
  * (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 1.5.0 [January 6, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -29,11 +29,13 @@
 struct png_struct_def
 {
 #ifdef PNG_SETJMP_SUPPORTED
-   jmp_buf png_jmpbuf;            /* used in png_error */
+   jmp_buf longjmp_buffer;    /* used in png_error */
    png_longjmp_ptr longjmp_fn;/* setjmp non-local goto function. */
 #endif
    png_error_ptr error_fn;    /* function for printing errors and aborting */
+#ifdef PNG_WARNINGS_SUPPORTED
    png_error_ptr warning_fn;  /* function for printing warnings */
+#endif
    png_voidp error_ptr;       /* user supplied struct for error functions */
    png_rw_ptr write_data_fn;  /* function for writing output data */
    png_rw_ptr read_data_fn;   /* function for reading input data */
@@ -64,11 +66,36 @@ struct png_struct_def
    z_stream zstream;          /* pointer to decompression structure (below) */
    png_bytep zbuf;            /* buffer for zlib */
    uInt zbuf_size;            /* size of zbuf (typically 65536) */
+#ifdef PNG_WRITE_SUPPORTED
+
+/* Added in 1.5.4: state to keep track of whether the zstream has been
+ * initialized and if so whether it is for IDAT or some other chunk.
+ */
+#define PNG_ZLIB_UNINITIALIZED 0
+#define PNG_ZLIB_FOR_IDAT      1
+#define PNG_ZLIB_FOR_TEXT      2 /* anything other than IDAT */
+#define PNG_ZLIB_USE_MASK      3 /* bottom two bits */
+#define PNG_ZLIB_IN_USE        4 /* a flag value */
+
+   png_uint_32 zlib_state;       /* State of zlib initialization */
+/* End of material added at libpng 1.5.4 */
+
    int zlib_level;            /* holds zlib compression level */
    int zlib_method;           /* holds zlib compression method */
    int zlib_window_bits;      /* holds zlib compression window bits */
    int zlib_mem_level;        /* holds zlib compression memory level */
    int zlib_strategy;         /* holds zlib compression strategy */
+#endif
+/* Added at libpng 1.5.4 */
+#if defined(PNG_WRITE_COMPRESSED_TEXT_SUPPORTED) || \
+    defined(PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED)
+   int zlib_text_level;            /* holds zlib compression level */
+   int zlib_text_method;           /* holds zlib compression method */
+   int zlib_text_window_bits;      /* holds zlib compression window bits */
+   int zlib_text_mem_level;        /* holds zlib compression memory level */
+   int zlib_text_strategy;         /* holds zlib compression strategy */
+#endif
+/* End of material added at libpng 1.5.4 */
 
    png_uint_32 width;         /* width of image in pixels */
    png_uint_32 height;        /* height of image in pixels */
@@ -84,6 +111,7 @@ struct png_struct_def
    png_bytep avg_row;         /* buffer to save "avg" row when filtering */
    png_bytep paeth_row;       /* buffer to save "Paeth" row when filtering */
    png_row_info row_info;     /* used for transformation routines */
+   png_size_t info_rowbytes;  /* Added in 1.5.4: cache of updated row bytes */
 
    png_uint_32 idat_size;     /* current IDAT size for read */
    png_uint_32 crc;           /* current chunk CRC value */
@@ -108,7 +136,8 @@ struct png_struct_def
    png_uint_16 filler;           /* filler bytes for pixel expansion */
 #endif
 
-#ifdef PNG_bKGD_SUPPORTED
+#if defined(PNG_bKGD_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
+   defined(PNG_READ_ALPHA_MODE_SUPPORTED)
    png_byte background_gamma_type;
    png_fixed_point background_gamma;
    png_color_16 background;   /* background color in screen gamma space */
@@ -209,7 +238,7 @@ struct png_struct_def
 #endif
 
 #ifdef PNG_TIME_RFC1123_SUPPORTED
-   png_charp time_buffer; /* String to hold RFC 1123 time text */
+   char time_buffer[29]; /* String to hold RFC 1123 time text */
 #endif
 
 /* New members added in libpng-1.0.6 */

GRRLIB/lib/png/pngtrans.c

@@ -1,7 +1,7 @@
 
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
- * Last changed in libpng 1.5.2 [March 31, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  * Copyright (c) 1998-2011 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.)
@@ -442,7 +442,11 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
    /* At the start sp will point to the first byte to copy and dp to where
     * it is copied to.  ep always points just beyond the end of the row, so
     * the loop simply copies (channels-1) channels until sp reaches ep.
+    *
+    * at_start:        0 -- convert AG, XG, ARGB, XRGB, AAGG, XXGG, etc.
+    *            nonzero -- convert GA, GX, RGBA, RGBX, GGAA, RRGGBBXX, etc.
     */
+
    /* GA, GX, XG cases */
    if (row_info->channels == 2)
    {
@@ -450,7 +454,7 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
       {
          if (at_start) /* Skip initial filler */
             ++sp;
-         else          /* Skip initial channels and, for sp, the filler */
+         else          /* Skip initial channel and, for sp, the filler */
             sp += 2, ++dp;
 
          /* For a 1 pixel wide image there is nothing to do */
@@ -462,9 +466,9 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
 
       else if (row_info->bit_depth == 16)
       {
-         if (at_start)
+         if (at_start) /* Skip initial filler */
             sp += 2;
-         else
+         else          /* Skip initial channel and, for sp, the filler */
             sp += 4, dp += 2;
 
          while (sp < ep)
@@ -502,9 +506,9 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
 
       else if (row_info->bit_depth == 16)
       {
-         if (at_start)
+         if (at_start) /* Skip initial filler */
             sp += 2;
-         else
+         else          /* Skip initial channels and, for sp, the filler */
             sp += 8, dp += 6;
 
          while (sp < ep)

GRRLIB/lib/png/pngwrite.c

@@ -1,7 +1,7 @@
 
 /* pngwrite.c - general routines to write a PNG file
  *
- * Last changed in libpng 1.5.1 [February 3, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  * Copyright (c) 1998-2011 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.)
@@ -99,8 +99,10 @@ png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)
          int keep = png_handle_as_unknown(png_ptr, up->name);
 
          if (keep != PNG_HANDLE_CHUNK_NEVER &&
-             up->location && !(up->location & PNG_HAVE_PLTE) &&
+             up->location &&
+             !(up->location & PNG_HAVE_PLTE) &&
              !(up->location & PNG_HAVE_IDAT) &&
+             !(up->location & PNG_AFTER_IDAT) &&
              ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
              (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
          {
@@ -273,8 +275,10 @@ png_write_info(png_structp png_ptr, png_infop info_ptr)
       {
          int keep = png_handle_as_unknown(png_ptr, up->name);
          if (keep != PNG_HANDLE_CHUNK_NEVER &&
-             up->location && (up->location & PNG_HAVE_PLTE) &&
+             up->location &&
+             (up->location & PNG_HAVE_PLTE) &&
              !(up->location & PNG_HAVE_IDAT) &&
+             !(up->location & PNG_AFTER_IDAT) &&
              ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
              (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
          {
@@ -380,7 +384,8 @@ png_write_end(png_structp png_ptr, png_infop info_ptr)
       {
          int keep = png_handle_as_unknown(png_ptr, up->name);
          if (keep != PNG_HANDLE_CHUNK_NEVER &&
-             up->location && (up->location & PNG_AFTER_IDAT) &&
+             up->location &&
+             (up->location & PNG_AFTER_IDAT) &&
              ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
              (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
          {
@@ -462,10 +467,9 @@ png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
    png_structp png_ptr;
 #ifdef PNG_SETJMP_SUPPORTED
 #ifdef USE_FAR_KEYWORD
-   jmp_buf png_jmpbuf;
+   jmp_buf tmp_jmpbuf;
 #endif
 #endif
-   int i;
 
    png_debug(1, "in png_create_write_struct");
 
@@ -489,12 +493,12 @@ png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
    encounter a png_error() will longjmp here.  Since the jmpbuf is
    then meaningless we abort instead of returning. */
 #ifdef USE_FAR_KEYWORD
-   if (setjmp(png_jmpbuf))
+   if (setjmp(tmp_jmpbuf))
 #else
    if (setjmp(png_jmpbuf(png_ptr))) /* sets longjmp to match setjmp */
 #endif
 #ifdef USE_FAR_KEYWORD
-   png_memcpy(png_jmpbuf(png_ptr), png_jmpbuf, png_sizeof(jmp_buf));
+   png_memcpy(png_jmpbuf(png_ptr), tmp_jmpbuf, png_sizeof(jmp_buf));
 #endif
       PNG_ABORT();
 #endif
@@ -504,49 +508,8 @@ png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
 #endif /* PNG_USER_MEM_SUPPORTED */
    png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
 
-   if (user_png_ver)
+   if (!png_user_version_check(png_ptr, user_png_ver))
-   {
+      png_cleanup_needed = 1;
-      i = 0;
-      do
-      {
-         if (user_png_ver[i] != png_libpng_ver[i])
-            png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
-      } while (png_libpng_ver[i++]);
-   }
-
-   if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
-   {
-     /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
-      * we must recompile any applications that use any older library version.
-      * For versions after libpng 1.0, we will be compatible, so we need
-      * only check the first digit.
-      */
-     if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
-         (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
-         (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
-     {
-#ifdef PNG_CONSOLE_IO_SUPPORTED
-        char msg[80];
-
-        if (user_png_ver)
-        {
-            png_snprintf2(msg, 80,
-                "Application built with libpng-%.20s"
-                " but running with %.20s",
-                user_png_ver,
-                png_libpng_ver);
-            png_warning(png_ptr, msg);
-         }
-#else
-         png_warning(png_ptr,
-             "Incompatible libpng version in application and library");
-#endif
-#ifdef PNG_ERROR_NUMBERS_SUPPORTED
-        png_ptr->flags = 0;
-#endif
-        png_cleanup_needed = 1;
-     }
-   }
 
    /* Initialize zbuf - compression buffer */
    png_ptr->zbuf_size = PNG_ZBUF_SIZE;
@@ -805,9 +768,11 @@ png_write_row(png_structp png_ptr, png_const_bytep row)
    }
 #endif
 
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
    /* Handle other transformations */
    if (png_ptr->transformations)
       png_do_write_transformations(png_ptr);
+#endif
 
 #ifdef PNG_MNG_FEATURES_SUPPORTED
    /* Write filter_method 64 (intrapixel differencing) only if
@@ -884,8 +849,6 @@ png_write_flush(png_structp png_ptr)
       {
          /* Write the IDAT and reset the zlib output buffer */
          png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
-         png_ptr->zstream.next_out = png_ptr->zbuf;
-         png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
          wrote_IDAT = 1;
       }
    } while (wrote_IDAT == 1);
@@ -896,8 +859,6 @@ png_write_flush(png_structp png_ptr)
       /* Write the IDAT and reset the zlib output buffer */
       png_write_IDAT(png_ptr, png_ptr->zbuf,
           png_ptr->zbuf_size - png_ptr->zstream.avail_out);
-      png_ptr->zstream.next_out = png_ptr->zbuf;
-      png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
    }
    png_ptr->flush_rows = 0;
    png_flush(png_ptr);
@@ -983,7 +944,9 @@ png_write_destroy(png_structp png_ptr)
    jmp_buf tmp_jmp; /* Save jump buffer */
 #endif
    png_error_ptr error_fn;
+#ifdef PNG_WARNINGS_SUPPORTED
    png_error_ptr warning_fn;
+#endif
    png_voidp error_ptr;
 #ifdef PNG_USER_MEM_SUPPORTED
    png_free_ptr free_fn;
@@ -992,7 +955,8 @@ png_write_destroy(png_structp png_ptr)
    png_debug(1, "in png_write_destroy");
 
    /* Free any memory zlib uses */
-   deflateEnd(&png_ptr->zstream);
+   if (png_ptr->zlib_state != PNG_ZLIB_UNINITIALIZED)
+      deflateEnd(&png_ptr->zstream);
 
    /* Free our memory.  png_free checks NULL for us. */
    png_free(png_ptr, png_ptr->zbuf);
@@ -1005,10 +969,6 @@ png_write_destroy(png_structp png_ptr)
    png_free(png_ptr, png_ptr->paeth_row);
 #endif
 
-#ifdef PNG_TIME_RFC1123_SUPPORTED
-   png_free(png_ptr, png_ptr->time_buffer);
-#endif
-
 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
    /* Use this to save a little code space, it doesn't free the filter_costs */
    png_reset_filter_heuristics(png_ptr);
@@ -1018,11 +978,13 @@ png_write_destroy(png_structp png_ptr)
 
 #ifdef PNG_SETJMP_SUPPORTED
    /* Reset structure */
-   png_memcpy(tmp_jmp, png_ptr->png_jmpbuf, png_sizeof(jmp_buf));
+   png_memcpy(tmp_jmp, png_ptr->longjmp_buffer, png_sizeof(jmp_buf));
 #endif
 
    error_fn = png_ptr->error_fn;
+#ifdef PNG_WARNINGS_SUPPORTED
    warning_fn = png_ptr->warning_fn;
+#endif
    error_ptr = png_ptr->error_ptr;
 #ifdef PNG_USER_MEM_SUPPORTED
    free_fn = png_ptr->free_fn;
@@ -1031,14 +993,16 @@ png_write_destroy(png_structp png_ptr)
    png_memset(png_ptr, 0, png_sizeof(png_struct));
 
    png_ptr->error_fn = error_fn;
+#ifdef PNG_WARNINGS_SUPPORTED
    png_ptr->warning_fn = warning_fn;
+#endif
    png_ptr->error_ptr = error_ptr;
 #ifdef PNG_USER_MEM_SUPPORTED
    png_ptr->free_fn = free_fn;
 #endif
 
 #ifdef PNG_SETJMP_SUPPORTED
-   png_memcpy(png_ptr->png_jmpbuf, tmp_jmp, png_sizeof(jmp_buf));
+   png_memcpy(png_ptr->longjmp_buffer, tmp_jmp, png_sizeof(jmp_buf));
 #endif
 }
 
@@ -1451,6 +1415,9 @@ png_set_compression_strategy(png_structp png_ptr, int strategy)
    png_ptr->zlib_strategy = strategy;
 }
 
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
 void PNGAPI
 png_set_compression_window_bits(png_structp png_ptr, int window_bits)
 {
@@ -1491,6 +1458,89 @@ png_set_compression_method(png_structp png_ptr, int method)
    png_ptr->zlib_method = method;
 }
 
+/* The following were added to libpng-1.5.4 */
+#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
+void PNGAPI
+png_set_text_compression_level(png_structp png_ptr, int level)
+{
+   png_debug(1, "in png_set_text_compression_level");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_LEVEL;
+   png_ptr->zlib_text_level = level;
+}
+
+void PNGAPI
+png_set_text_compression_mem_level(png_structp png_ptr, int mem_level)
+{
+   png_debug(1, "in png_set_text_compression_mem_level");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL;
+   png_ptr->zlib_text_mem_level = mem_level;
+}
+
+void PNGAPI
+png_set_text_compression_strategy(png_structp png_ptr, int strategy)
+{
+   png_debug(1, "in png_set_text_compression_strategy");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_STRATEGY;
+   png_ptr->zlib_text_strategy = strategy;
+}
+
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
+void PNGAPI
+png_set_text_compression_window_bits(png_structp png_ptr, int window_bits)
+{
+   if (png_ptr == NULL)
+      return;
+
+   if (window_bits > 15)
+      png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
+
+   else if (window_bits < 8)
+      png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
+
+#ifndef WBITS_8_OK
+   /* Avoid libpng bug with 256-byte windows */
+   if (window_bits == 8)
+      {
+        png_warning(png_ptr, "Text compression window is being reset to 512");
+        window_bits = 9;
+      }
+
+#endif
+   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS;
+   png_ptr->zlib_text_window_bits = window_bits;
+}
+
+void PNGAPI
+png_set_text_compression_method(png_structp png_ptr, int method)
+{
+   png_debug(1, "in png_set_text_compression_method");
+
+   if (png_ptr == NULL)
+      return;
+
+   if (method != 8)
+      png_warning(png_ptr, "Only compression method 8 is supported by PNG");
+
+   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_METHOD;
+   png_ptr->zlib_text_method = method;
+}
+#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
+/* end of API added to libpng-1.5.4 */
+
 void PNGAPI
 png_set_write_status_fn(png_structp png_ptr, png_write_status_ptr write_row_fn)
 {
@@ -1557,7 +1607,7 @@ png_write_png(png_structp png_ptr, png_infop info_ptr,
 #endif
 
 #ifdef PNG_WRITE_FILLER_SUPPORTED
-   /* Pack XRGB/RGBX/ARGB/RGBA into * RGB (4 channels -> 3 channels) */
+   /* Pack XRGB/RGBX/ARGB/RGBA into RGB (4 channels -> 3 channels) */
    if (transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER)
       png_set_filler(png_ptr, 0, PNG_FILLER_AFTER);
 

GRRLIB/lib/png/pngwtran.c

@@ -1,7 +1,7 @@
 
 /* pngwtran.c - transforms the data in a row for PNG writers
  *
- * Last changed in libpng 1.5.2 [March 31, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  * Copyright (c) 1998-2011 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.)
@@ -15,6 +15,7 @@
 
 #ifdef PNG_WRITE_SUPPORTED
 
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
 /* Transform the data according to the user's wishes.  The order of
  * transformations is significant.
  */
@@ -45,7 +46,7 @@ png_do_write_transformations(png_structp png_ptr)
 #ifdef PNG_WRITE_FILLER_SUPPORTED
    if (png_ptr->transformations & PNG_FILLER)
       png_do_strip_channel(&(png_ptr->row_info), png_ptr->row_buf + 1,
-         !(png_ptr->flags & PNG_FILLER_AFTER));
+         !(png_ptr->flags & PNG_FLAG_FILLER_AFTER));
 #endif
 
 #ifdef PNG_WRITE_PACKSWAP_SUPPORTED
@@ -563,6 +564,7 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
    }
 }
 #endif
+#endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */
 
 #ifdef PNG_MNG_FEATURES_SUPPORTED
 /* Undoes intrapixel differencing  */

GRRLIB/lib/png/pngwutil.c

@@ -1,7 +1,7 @@
 
 /* pngwutil.c - utilities to write a PNG file
  *
- * Last changed in libpng 1.5.0 [January 6, 2011]
+ * Last changed in libpng 1.5.4 [July 7, 2011]
  * Copyright (c) 1998-2011 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.)
@@ -192,7 +192,149 @@ png_write_chunk_end(png_structp png_ptr)
    png_write_data(png_ptr, buf, (png_size_t)4);
 }
 
-#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_iCCP_SUPPORTED)
+/* Initialize the compressor for the appropriate type of compression. */
+static void
+png_zlib_claim(png_structp png_ptr, png_uint_32 state)
+{
+   if (!(png_ptr->zlib_state & PNG_ZLIB_IN_USE))
+   {
+      /* If already initialized for 'state' do not re-init. */
+      if (png_ptr->zlib_state != state)
+      {
+         int ret = Z_OK;
+         png_const_charp who = "-";
+
+         /* If actually initialized for another state do a deflateEnd. */
+         if (png_ptr->zlib_state != PNG_ZLIB_UNINITIALIZED)
+         {
+            ret = deflateEnd(&png_ptr->zstream);
+            who = "end";
+            png_ptr->zlib_state = PNG_ZLIB_UNINITIALIZED;
+         }
+
+         /* zlib itself detects an incomplete state on deflateEnd */
+         if (ret == Z_OK) switch (state)
+         {
+#           ifdef PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
+               case PNG_ZLIB_FOR_TEXT:
+                  ret = deflateInit2(&png_ptr->zstream,
+                     png_ptr->zlib_text_level, png_ptr->zlib_text_method,
+                     png_ptr->zlib_text_window_bits,
+                     png_ptr->zlib_text_mem_level, png_ptr->zlib_text_strategy);
+                  who = "text";
+                  break;
+#           endif
+
+            case PNG_ZLIB_FOR_IDAT:
+               ret = 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);
+               who = "IDAT";
+               break;
+
+            default:
+               png_error(png_ptr, "invalid zlib state");
+         }
+
+         if (ret == Z_OK)
+            png_ptr->zlib_state = state;
+
+         else /* an error in deflateEnd or deflateInit2 */
+         {
+            size_t pos = 0;
+            char msg[64];
+
+            pos = png_safecat(msg, sizeof msg, pos,
+               "zlib failed to initialize compressor (");
+            pos = png_safecat(msg, sizeof msg, pos, who);
+
+            switch (ret)
+            {
+               case Z_VERSION_ERROR:
+                  pos = png_safecat(msg, sizeof msg, pos, ") version error");
+                  break;
+
+               case Z_STREAM_ERROR:
+                  pos = png_safecat(msg, sizeof msg, pos, ") stream error");
+                  break;
+
+               case Z_MEM_ERROR:
+                  pos = png_safecat(msg, sizeof msg, pos, ") memory error");
+                  break;
+
+               default:
+                  pos = png_safecat(msg, sizeof msg, pos, ") unknown error");
+                  break;
+            }
+
+            png_error(png_ptr, msg);
+         }
+      }
+
+      /* Here on success, claim the zstream: */
+      png_ptr->zlib_state |= PNG_ZLIB_IN_USE;
+   }
+
+   else
+      png_error(png_ptr, "zstream already in use (internal error)");
+}
+
+/* The opposite: release the stream.  It is also reset, this API will warn on
+ * error but will not fail.
+ */
+static void
+png_zlib_release(png_structp png_ptr)
+{
+   if (png_ptr->zlib_state & PNG_ZLIB_IN_USE)
+   {
+      int ret = deflateReset(&png_ptr->zstream);
+
+      png_ptr->zlib_state &= ~PNG_ZLIB_IN_USE;
+
+      if (ret != Z_OK)
+      {
+         png_const_charp err;
+         PNG_WARNING_PARAMETERS(p)
+
+         switch (ret)
+         {
+            case Z_VERSION_ERROR:
+               err = "version";
+               break;
+
+            case Z_STREAM_ERROR:
+               err = "stream";
+               break;
+
+            case Z_MEM_ERROR:
+               err = "memory";
+               break;
+
+            default:
+               err = "unknown";
+               break;
+         }
+
+         png_warning_parameter_signed(p, 1, PNG_NUMBER_FORMAT_d, ret);
+         png_warning_parameter(p, 2, err);
+
+         if (png_ptr->zstream.msg)
+            err = png_ptr->zstream.msg;
+         else
+            err = "[no zlib message]";
+
+         png_warning_parameter(p, 3, err);
+
+         png_formatted_warning(png_ptr, p,
+            "zlib failed to reset compressor: @1(@2): @3");
+      }
+   }
+
+   else
+      png_warning(png_ptr, "zstream not in use (internal error)");
+}
+
+#ifdef PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
 /* This pair of functions encapsulates the operation of (a) compressing a
  * text string, and (b) issuing it later as a series of chunk data writes.
  * The compression_state structure is shared context for these functions
@@ -220,25 +362,22 @@ png_text_compress(png_structp png_ptr,
    comp->max_output_ptr = 0;
    comp->output_ptr = NULL;
    comp->input = NULL;
-   comp->input_len = 0;
+   comp->input_len = text_len;
 
    /* We may just want to pass the text right through */
    if (compression == PNG_TEXT_COMPRESSION_NONE)
    {
       comp->input = (png_const_bytep)text;
-      comp->input_len = text_len;
       return((int)text_len);
    }
 
    if (compression >= PNG_TEXT_COMPRESSION_LAST)
    {
-#ifdef PNG_CONSOLE_IO_SUPPORTED
+      PNG_WARNING_PARAMETERS(p)
-      char msg[50];
+
-      png_snprintf(msg, 50, "Unknown compression type %d", compression);
+      png_warning_parameter_signed(p, 1, PNG_NUMBER_FORMAT_d,
-      png_warning(png_ptr, msg);
+         compression);
-#else
+      png_formatted_warning(png_ptr, p, "Unknown compression type @1");
-      png_warning(png_ptr, "Unknown compression type");
-#endif
    }
 
    /* We can't write the chunk until we find out how much data we have,
@@ -255,10 +394,12 @@ png_text_compress(png_structp png_ptr,
     * data, or if the input string is incredibly large (although this
     * wouldn't cause a failure, just a slowdown due to swapping).
     */
+   png_zlib_claim(png_ptr, PNG_ZLIB_FOR_TEXT);
 
    /* Set up the compression buffers */
    /* TODO: the following cast hides a potential overflow problem. */
    png_ptr->zstream.avail_in = (uInt)text_len;
+
    /* NOTE: assume zlib doesn't overwrite the input */
    png_ptr->zstream.next_in = (Bytef *)text;
    png_ptr->zstream.avail_out = png_ptr->zbuf_size;
@@ -418,6 +559,68 @@ png_write_compressed_data_out(png_structp png_ptr, compression_state *comp)
       return;
    }
 
+#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
+   if (comp->input_len >= 2 && comp->input_len < 16384)
+   {
+      unsigned int z_cmf;  /* zlib compression method and flags */
+
+      /* Optimize the CMF field in the zlib stream.  This hack of the zlib
+       * stream is compliant to the stream specification.
+       */
+
+      if (comp->num_output_ptr)
+        z_cmf = comp->output_ptr[0][0];
+      else
+        z_cmf = png_ptr->zbuf[0];
+
+      if ((z_cmf & 0x0f) == 8 && (z_cmf & 0xf0) <= 0x70)
+      {
+         unsigned int z_cinfo;
+         unsigned int half_z_window_size;
+         png_size_t uncompressed_text_size = comp->input_len;
+
+         z_cinfo = z_cmf >> 4;
+         half_z_window_size = 1 << (z_cinfo + 7);
+
+         while (uncompressed_text_size <= half_z_window_size &&
+             half_z_window_size >= 256)
+         {
+            z_cinfo--;
+            half_z_window_size >>= 1;
+         }
+
+         z_cmf = (z_cmf & 0x0f) | (z_cinfo << 4);
+
+         if (comp->num_output_ptr)
+         {
+
+           if (comp->output_ptr[0][0] != z_cmf)
+           {
+              int tmp;
+
+              comp->output_ptr[0][0] = (png_byte)z_cmf;
+              tmp = comp->output_ptr[0][1] & 0xe0;
+              tmp += 0x1f - ((z_cmf << 8) + tmp) % 0x1f;
+              comp->output_ptr[0][1] = (png_byte)tmp;
+           }
+         }
+         else
+         {
+            int tmp;
+
+            png_ptr->zbuf[0] = (png_byte)z_cmf;
+            tmp = png_ptr->zbuf[1] & 0xe0;
+            tmp += 0x1f - ((z_cmf << 8) + tmp) % 0x1f;
+            png_ptr->zbuf[1] = (png_byte)tmp;
+         }
+      }
+
+      else
+         png_error(png_ptr,
+             "Invalid zlib compression method or flags in non-IDAT chunk");
+   }
+#endif /* PNG_WRITE_OPTIMIZE_CMF_SUPPORTED */
+
    /* Write saved output buffers, if any */
    for (i = 0; i < comp->num_output_ptr; i++)
    {
@@ -436,10 +639,9 @@ png_write_compressed_data_out(png_structp png_ptr, compression_state *comp)
           (png_size_t)(png_ptr->zbuf_size - png_ptr->zstream.avail_out));
 
    /* Reset zlib for another zTXt/iTXt or image data */
-   deflateReset(&png_ptr->zstream);
+   png_zlib_release(png_ptr);
-   png_ptr->zstream.data_type = Z_BINARY;
 }
-#endif
+#endif /* PNG_WRITE_COMPRESSED_TEXT_SUPPORTED */
 
 /* Write the IHDR chunk, and update the png_struct with the necessary
  * information.  Note that the rest of this code depends upon this
@@ -451,7 +653,6 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
     int interlace_type)
 {
    PNG_IHDR;
-   int ret;
 
    png_byte buf[13]; /* Buffer to store the IHDR info */
 
@@ -632,35 +833,35 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
    if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_METHOD))
       png_ptr->zlib_method = 8;
 
-   ret = deflateInit2(&png_ptr->zstream, png_ptr->zlib_level,
+#ifdef PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
-       png_ptr->zlib_method, png_ptr->zlib_window_bits,
+#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
-       png_ptr->zlib_mem_level, png_ptr->zlib_strategy);
+   if (!(png_ptr->flags & PNG_FLAG_ZTXT_CUSTOM_STRATEGY))
+      png_ptr->zlib_text_strategy = Z_DEFAULT_STRATEGY;
 
-   if (ret != Z_OK)
+   if (!(png_ptr->flags & PNG_FLAG_ZTXT_CUSTOM_LEVEL))
-   {
+      png_ptr->zlib_text_level = png_ptr->zlib_level;
-      if (ret == Z_VERSION_ERROR)
-         png_error(png_ptr,
-            "zlib failed to initialize compressor -- version error");
 
-      if (ret == Z_STREAM_ERROR)
+   if (!(png_ptr->flags & PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL))
-         png_error(png_ptr,
+      png_ptr->zlib_text_mem_level = png_ptr->zlib_mem_level;
-             "zlib failed to initialize compressor -- stream error");
 
-      if (ret == Z_MEM_ERROR)
+   if (!(png_ptr->flags & PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS))
-         png_error(png_ptr,
+      png_ptr->zlib_text_window_bits = png_ptr->zlib_window_bits;
-             "zlib failed to initialize compressor -- mem error");
 
-      png_error(png_ptr, "zlib failed to initialize compressor");
+   if (!(png_ptr->flags & PNG_FLAG_ZTXT_CUSTOM_METHOD))
-   }
+      png_ptr->zlib_text_method = png_ptr->zlib_method;
+#else
+   png_ptr->zlib_text_strategy = Z_DEFAULT_STRATEGY;
+   png_ptr->zlib_text_level = png_ptr->zlib_level;
+   png_ptr->zlib_text_mem_level = png_ptr->zlib_mem_level;
+   png_ptr->zlib_text_window_bits = png_ptr->zlib_window_bits;
+   png_ptr->zlib_text_method = png_ptr->zlib_method;
+#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
+#endif /* PNG_WRITE_COMPRESSED_TEXT_SUPPORTED */
 
-   png_ptr->zstream.next_out = png_ptr->zbuf;
+   /* Record that the compressor has not yet been initialized. */
-   png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+   png_ptr->zlib_state = PNG_ZLIB_UNINITIALIZED;
-   /* libpng is not interested in zstream.data_type, so set it
-    * to a predefined value, to avoid its evaluation inside zlib
-    */
-   png_ptr->zstream.data_type = Z_BINARY;
 
-   png_ptr->mode = PNG_HAVE_IHDR;
+   png_ptr->mode = PNG_HAVE_IHDR; /* not READY_FOR_ZTXT */
 }
 
 /* Write the palette.  We are careful not to trust png_color to be in the
@@ -745,12 +946,15 @@ png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
 
    png_debug(1, "in png_write_IDAT");
 
-   /* Optimize the CMF field in the zlib stream. */
+#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
-   /* This hack of the zlib stream is compliant to the stream specification. */
    if (!(png_ptr->mode & PNG_HAVE_IDAT) &&
        png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
    {
+      /* Optimize the CMF field in the zlib stream.  This hack of the zlib
+       * stream is compliant to the stream specification.
+       */
       unsigned int z_cmf = data[0];  /* zlib compression method and flags */
+
       if ((z_cmf & 0x0f) == 8 && (z_cmf & 0xf0) <= 0x70)
       {
          /* Avoid memory underflows and multiplication overflows.
@@ -761,11 +965,29 @@ png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
          if (length >= 2 &&
              png_ptr->height < 16384 && png_ptr->width < 16384)
          {
+            /* Compute the maximum possible length of the datastream */
+
+            /* Number of pixels, plus for each row a filter byte
+             * and possibly a padding byte, so increase the maximum
+             * size to account for these.
+             */
+            unsigned int z_cinfo;
+            unsigned int half_z_window_size;
             png_uint_32 uncompressed_idat_size = png_ptr->height *
                 ((png_ptr->width *
                 png_ptr->channels * png_ptr->bit_depth + 15) >> 3);
-            unsigned int z_cinfo = z_cmf >> 4;
+
-            unsigned int half_z_window_size = 1 << (z_cinfo + 7);
+            /* If it's interlaced, each block of 8 rows is sent as up to
+             * 14 rows, i.e., 6 additional rows, each with a filter byte
+             * and possibly a padding byte
+             */
+            if (png_ptr->interlaced)
+               uncompressed_idat_size += ((png_ptr->height + 7)/8) *
+                   (png_ptr->bit_depth < 8 ? 12 : 6);
+
+            z_cinfo = z_cmf >> 4;
+            half_z_window_size = 1 << (z_cinfo + 7);
+
             while (uncompressed_idat_size <= half_z_window_size &&
                 half_z_window_size >= 256)
             {
@@ -790,9 +1012,17 @@ png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
          png_error(png_ptr,
              "Invalid zlib compression method or flags in IDAT");
    }
+#endif /* PNG_WRITE_OPTIMIZE_CMF_SUPPORTED */
 
    png_write_chunk(png_ptr, png_IDAT, data, length);
    png_ptr->mode |= PNG_HAVE_IDAT;
+
+   /* Prior to 1.5.4 this code was replicated in every caller (except at the
+    * end, where it isn't technically necessary).  Since this function has
+    * flushed the data we can safely reset the zlib output buffer here.
+    */
+   png_ptr->zstream.next_out = png_ptr->zbuf;
+   png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
 }
 
 /* Write an IEND chunk */
@@ -918,7 +1148,10 @@ png_write_iCCP(png_structp png_ptr, png_const_charp name, int compression_type,
        (png_size_t)(name_len + 2));
 
    if (profile_len)
+   {
+      comp.input_len = profile_len;
       png_write_compressed_data_out(png_ptr, &comp);
+   }
 
    png_write_chunk_end(png_ptr);
    png_free(png_ptr, new_name);
@@ -1313,15 +1546,11 @@ png_check_keyword(png_structp png_ptr, png_const_charp key, png_charpp new_key)
       if ((png_byte)*ikp < 0x20 ||
          ((png_byte)*ikp > 0x7E && (png_byte)*ikp < 0xA1))
       {
-#ifdef PNG_CONSOLE_IO_SUPPORTED
+         PNG_WARNING_PARAMETERS(p)
-         char msg[40];
 
-         png_snprintf(msg, 40,
+         png_warning_parameter_unsigned(p, 1, PNG_NUMBER_FORMAT_02x,
-             "invalid keyword character 0x%02X", (png_byte)*ikp);
+            (png_byte)*ikp);
-         png_warning(png_ptr, msg);
+         png_formatted_warning(png_ptr, p, "invalid keyword character 0x@1");
-#else
-         png_warning(png_ptr, "invalid character in keyword");
-#endif
          *dp = ' ';
       }
 
@@ -1499,6 +1728,7 @@ png_write_zTXt(png_structp png_ptr, png_const_charp key, png_const_charp text,
    png_write_chunk_data(png_ptr, &buf, (png_size_t)1);
 
    /* Write the compressed data */
+   comp.input_len = text_len;
    png_write_compressed_data_out(png_ptr, &comp);
 
    /* Close the chunk */
@@ -1871,6 +2101,7 @@ png_write_start_row(png_structp png_ptr)
       png_ptr->usr_width = png_ptr->width;
    }
 
+   png_zlib_claim(png_ptr, PNG_ZLIB_FOR_IDAT);
    png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
    png_ptr->zstream.next_out = png_ptr->zbuf;
 }
@@ -1992,7 +2223,7 @@ png_write_finish_row(png_structp png_ptr)
           png_ptr->zstream.avail_out);
    }
 
-   deflateReset(&png_ptr->zstream);
+   png_zlib_release(png_ptr);
    png_ptr->zstream.data_type = Z_BINARY;
 }
 
@@ -2181,6 +2412,8 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
  * been specified by the application, and then writes the row out with the
  * chosen filter.
  */
+static void png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row);
+
 #define PNG_MAXSUM (((png_uint_32)(-1)) >> 1)
 #define PNG_HISHIFT 10
 #define PNG_LOMASK ((png_uint_32)0xffffL)
@@ -2856,7 +3089,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
 
 
 /* Do the actual writing of a previously filtered row. */
-void /* PRIVATE */
+static void
 png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row)
 {
    png_size_t avail;
@@ -2916,8 +3149,6 @@ png_write_filtered_row(png_structp png_ptr, png_bytep filtered_row)
       {
          /* Write the IDAT and reset the zlib output buffer */
          png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
-         png_ptr->zstream.next_out = png_ptr->zbuf;
-         png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
       }
    /* Repeat until all data has been compressed */
    } while (avail > 0 || png_ptr->zstream.avail_in > 0);