external/libpng 1.2.29

1 files changed, 1268 insertions, 0 deletions

diff --git a/pngset.c b/pngset.c
new file mode 100644
index 0000000..8b25ca5
--- /dev/null
+++ b/pngset.c
@@ -0,0 +1,1268 @@
+
+/* pngset.c - storage of image information into info struct
+ *
+ * Last changed in libpng 1.2.27 [April 29, 2008]
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1998-2008 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.)
+ *
+ * The functions here are used during reads to store data from the file
+ * into the info struct, and during writes to store application data
+ * into the info struct for writing into the file.  This abstracts the
+ * info struct and allows us to change the structure in the future.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+
+#if defined(PNG_bKGD_SUPPORTED)
+void PNGAPI
+png_set_bKGD(png_structp png_ptr, png_infop info_ptr, png_color_16p background)
+{
+   png_debug1(1, "in %s storage function\n", "bKGD");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_memcpy(&(info_ptr->background), background, png_sizeof(png_color_16));
+   info_ptr->valid |= PNG_INFO_bKGD;
+}
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_cHRM(png_structp png_ptr, png_infop info_ptr,
+   double white_x, double white_y, double red_x, double red_y,
+   double green_x, double green_y, double blue_x, double blue_y)
+{
+   png_debug1(1, "in %s storage function\n", "cHRM");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+   if (!(white_x || white_y || red_x || red_y || green_x || green_y ||
+       blue_x || blue_y))
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set all-zero chromaticity values");
+      return;
+   }
+   if (white_x < 0.0 || white_y < 0.0 ||
+         red_x < 0.0 ||   red_y < 0.0 ||
+       green_x < 0.0 || green_y < 0.0 ||
+        blue_x < 0.0 ||  blue_y < 0.0)
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set negative chromaticity value");
+      return;
+   }
+   if (white_x > 21474.83 || white_y > 21474.83 ||
+         red_x > 21474.83 ||   red_y > 21474.83 ||
+       green_x > 21474.83 || green_y > 21474.83 ||
+        blue_x > 21474.83 ||  blue_y > 21474.83)
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set chromaticity value exceeding 21474.83");
+      return;
+   }
+
+   info_ptr->x_white = (float)white_x;
+   info_ptr->y_white = (float)white_y;
+   info_ptr->x_red   = (float)red_x;
+   info_ptr->y_red   = (float)red_y;
+   info_ptr->x_green = (float)green_x;
+   info_ptr->y_green = (float)green_y;
+   info_ptr->x_blue  = (float)blue_x;
+   info_ptr->y_blue  = (float)blue_y;
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   info_ptr->int_x_white = (png_fixed_point)(white_x*100000.+0.5);
+   info_ptr->int_y_white = (png_fixed_point)(white_y*100000.+0.5);
+   info_ptr->int_x_red   = (png_fixed_point)(  red_x*100000.+0.5);
+   info_ptr->int_y_red   = (png_fixed_point)(  red_y*100000.+0.5);
+   info_ptr->int_x_green = (png_fixed_point)(green_x*100000.+0.5);
+   info_ptr->int_y_green = (png_fixed_point)(green_y*100000.+0.5);
+   info_ptr->int_x_blue  = (png_fixed_point)( blue_x*100000.+0.5);
+   info_ptr->int_y_blue  = (png_fixed_point)( blue_y*100000.+0.5);
+#endif
+   info_ptr->valid |= PNG_INFO_cHRM;
+}
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void PNGAPI
+png_set_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
+   png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
+   png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
+   png_fixed_point blue_x, png_fixed_point blue_y)
+{
+   png_debug1(1, "in %s storage function\n", "cHRM");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if (!(white_x || white_y || red_x || red_y || green_x || green_y ||
+       blue_x || blue_y))
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set all-zero chromaticity values");
+      return;
+   }
+   if (white_x < 0 || white_y < 0 ||
+         red_x < 0 ||   red_y < 0 ||
+       green_x < 0 || green_y < 0 ||
+        blue_x < 0 ||  blue_y < 0)
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set negative chromaticity value");
+      return;
+   }
+   if (white_x > (png_fixed_point) PNG_UINT_31_MAX ||
+       white_y > (png_fixed_point) PNG_UINT_31_MAX ||
+         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");
+      return;
+   }
+   info_ptr->int_x_white = white_x;
+   info_ptr->int_y_white = white_y;
+   info_ptr->int_x_red   = red_x;
+   info_ptr->int_y_red   = red_y;
+   info_ptr->int_x_green = green_x;
+   info_ptr->int_y_green = green_y;
+   info_ptr->int_x_blue  = blue_x;
+   info_ptr->int_y_blue  = blue_y;
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   info_ptr->x_white = (float)(white_x/100000.);
+   info_ptr->y_white = (float)(white_y/100000.);
+   info_ptr->x_red   = (float)(  red_x/100000.);
+   info_ptr->y_red   = (float)(  red_y/100000.);
+   info_ptr->x_green = (float)(green_x/100000.);
+   info_ptr->y_green = (float)(green_y/100000.);
+   info_ptr->x_blue  = (float)( blue_x/100000.);
+   info_ptr->y_blue  = (float)( blue_y/100000.);
+#endif
+   info_ptr->valid |= PNG_INFO_cHRM;
+}
+#endif
+#endif
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma)
+{
+   double gamma;
+   png_debug1(1, "in %s storage function\n", "gAMA");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   /* Check for overflow */
+   if (file_gamma > 21474.83)
+   {
+      png_warning(png_ptr, "Limiting gamma to 21474.83");
+      gamma=21474.83;
+   }
+   else
+      gamma=file_gamma;
+   info_ptr->gamma = (float)gamma;
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   info_ptr->int_gamma = (int)(gamma*100000.+.5);
+#endif
+   info_ptr->valid |= PNG_INFO_gAMA;
+   if(gamma == 0.0)
+      png_warning(png_ptr, "Setting gamma=0");
+}
+#endif
+void PNGAPI
+png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point
+   int_gamma)
+{
+   png_fixed_point gamma;
+
+   png_debug1(1, "in %s storage function\n", "gAMA");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if (int_gamma > (png_fixed_point) PNG_UINT_31_MAX)
+   {
+     png_warning(png_ptr, "Limiting gamma to 21474.83");
+     gamma=PNG_UINT_31_MAX;
+   }
+   else
+   {
+     if (int_gamma < 0)
+     {
+       png_warning(png_ptr, "Setting negative gamma to zero");
+       gamma=0;
+     }
+     else
+       gamma=int_gamma;
+   }
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   info_ptr->gamma = (float)(gamma/100000.);
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   info_ptr->int_gamma = gamma;
+#endif
+   info_ptr->valid |= PNG_INFO_gAMA;
+   if(gamma == 0)
+      png_warning(png_ptr, "Setting gamma=0");
+}
+#endif
+
+#if defined(PNG_hIST_SUPPORTED)
+void PNGAPI
+png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p hist)
+{
+   int i;
+
+   png_debug1(1, "in %s storage function\n", "hIST");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+   if (info_ptr->num_palette == 0 || info_ptr->num_palette
+       > PNG_MAX_PALETTE_LENGTH)
+   {
+       png_warning(png_ptr,
+          "Invalid palette size, hIST allocation skipped.");
+       return;
+   }
+
+#ifdef PNG_FREE_ME_SUPPORTED
+   png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);
+#endif
+   /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in version
+      1.2.1 */
+   png_ptr->hist = (png_uint_16p)png_malloc_warn(png_ptr,
+      (png_uint_32)(PNG_MAX_PALETTE_LENGTH * png_sizeof (png_uint_16)));
+   if (png_ptr->hist == NULL)
+     {
+       png_warning(png_ptr, "Insufficient memory for hIST chunk data.");
+       return;
+     }
+
+   for (i = 0; i < info_ptr->num_palette; i++)
+       png_ptr->hist[i] = hist[i];
+   info_ptr->hist = png_ptr->hist;
+   info_ptr->valid |= PNG_INFO_hIST;
+
+#ifdef PNG_FREE_ME_SUPPORTED
+   info_ptr->free_me |= PNG_FREE_HIST;
+#else
+   png_ptr->flags |= PNG_FLAG_FREE_HIST;
+#endif
+}
+#endif
+
+void PNGAPI
+png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 width, png_uint_32 height, int bit_depth,
+   int color_type, int interlace_type, int compression_type,
+   int filter_type)
+{
+   png_debug1(1, "in %s storage function\n", "IHDR");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   /* check for width and height valid values */
+   if (width == 0 || height == 0)
+      png_error(png_ptr, "Image width or height is zero in IHDR");
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+   if (width > png_ptr->user_width_max || height > png_ptr->user_height_max)
+      png_error(png_ptr, "image size exceeds user limits in IHDR");
+#else
+   if (width > PNG_USER_WIDTH_MAX || height > PNG_USER_HEIGHT_MAX)
+      png_error(png_ptr, "image size exceeds user limits in IHDR");
+#endif
+   if (width > PNG_UINT_31_MAX || height > PNG_UINT_31_MAX)
+      png_error(png_ptr, "Invalid image size in IHDR");
+   if ( width > (PNG_UINT_32_MAX
+                 >> 3)      /* 8-byte RGBA pixels */
+                 - 64       /* bigrowbuf hack */
+                 - 1        /* filter byte */
+                 - 7*8      /* rounding of width to multiple of 8 pixels */
+                 - 8)       /* extra max_pixel_depth pad */
+      png_warning(png_ptr, "Width is too large for libpng to process pixels");
+
+   /* check other values */
+   if (bit_depth != 1 && bit_depth != 2 && bit_depth != 4 &&
+      bit_depth != 8 && bit_depth != 16)
+      png_error(png_ptr, "Invalid bit depth in IHDR");
+
+   if (color_type < 0 || color_type == 1 ||
+      color_type == 5 || color_type > 6)
+      png_error(png_ptr, "Invalid color type in IHDR");
+
+   if (((color_type == PNG_COLOR_TYPE_PALETTE) && bit_depth > 8) ||
+       ((color_type == PNG_COLOR_TYPE_RGB ||
+         color_type == PNG_COLOR_TYPE_GRAY_ALPHA ||
+         color_type == PNG_COLOR_TYPE_RGB_ALPHA) && bit_depth < 8))
+      png_error(png_ptr, "Invalid color type/bit depth combination in IHDR");
+
+   if (interlace_type >= PNG_INTERLACE_LAST)
+      png_error(png_ptr, "Unknown interlace method in IHDR");
+
+   if (compression_type != PNG_COMPRESSION_TYPE_BASE)
+      png_error(png_ptr, "Unknown compression method in IHDR");
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+   /* Accept filter_method 64 (intrapixel differencing) only if
+    * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
+    * 2. Libpng did not read a PNG signature (this filter_method is only
+    *    used in PNG datastreams that are embedded in MNG datastreams) and
+    * 3. The application called png_permit_mng_features with a mask that
+    *    included PNG_FLAG_MNG_FILTER_64 and
+    * 4. The filter_method is 64 and
+    * 5. The color_type is RGB or RGBA
+    */
+   if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&png_ptr->mng_features_permitted)
+      png_warning(png_ptr,"MNG features are not allowed in a PNG datastream");
+   if(filter_type != PNG_FILTER_TYPE_BASE)
+   {
+     if(!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+        (filter_type == PNG_INTRAPIXEL_DIFFERENCING) &&
+        ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
+        (color_type == PNG_COLOR_TYPE_RGB ||
+         color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
+        png_error(png_ptr, "Unknown filter method in IHDR");
+     if(png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)
+        png_warning(png_ptr, "Invalid filter method in IHDR");
+   }
+#else
+   if(filter_type != PNG_FILTER_TYPE_BASE)
+      png_error(png_ptr, "Unknown filter method in IHDR");
+#endif
+
+   info_ptr->width = width;
+   info_ptr->height = height;
+   info_ptr->bit_depth = (png_byte)bit_depth;
+   info_ptr->color_type =(png_byte) color_type;
+   info_ptr->compression_type = (png_byte)compression_type;
+   info_ptr->filter_type = (png_byte)filter_type;
+   info_ptr->interlace_type = (png_byte)interlace_type;
+   if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      info_ptr->channels = 1;
+   else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
+      info_ptr->channels = 3;
+   else
+      info_ptr->channels = 1;
+   if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
+      info_ptr->channels++;
+   info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
+
+   /* check for potential overflow */
+   if (width > (PNG_UINT_32_MAX
+                 >> 3)      /* 8-byte RGBA pixels */
+                 - 64       /* bigrowbuf hack */
+                 - 1        /* filter byte */
+                 - 7*8      /* rounding of width to multiple of 8 pixels */
+                 - 8)       /* extra max_pixel_depth pad */
+      info_ptr->rowbytes = (png_size_t)0;
+   else
+      info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth,width);
+}
+
+#if defined(PNG_oFFs_SUPPORTED)
+void PNGAPI
+png_set_oFFs(png_structp png_ptr, png_infop info_ptr,
+   png_int_32 offset_x, png_int_32 offset_y, int unit_type)
+{
+   png_debug1(1, "in %s storage function\n", "oFFs");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->x_offset = offset_x;
+   info_ptr->y_offset = offset_y;
+   info_ptr->offset_unit_type = (png_byte)unit_type;
+   info_ptr->valid |= PNG_INFO_oFFs;
+}
+#endif
+
+#if defined(PNG_pCAL_SUPPORTED)
+void PNGAPI
+png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
+   png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
+   png_charp units, png_charpp params)
+{
+   png_uint_32 length;
+   int i;
+
+   png_debug1(1, "in %s storage function\n", "pCAL");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   length = png_strlen(purpose) + 1;
+   png_debug1(3, "allocating purpose for info (%lu bytes)\n", length);
+   info_ptr->pcal_purpose = (png_charp)png_malloc_warn(png_ptr, length);
+   if (info_ptr->pcal_purpose == NULL)
+     {
+       png_warning(png_ptr, "Insufficient memory for pCAL purpose.");
+       return;
+     }
+   png_memcpy(info_ptr->pcal_purpose, purpose, (png_size_t)length);
+
+   png_debug(3, "storing X0, X1, type, and nparams in info\n");
+   info_ptr->pcal_X0 = X0;
+   info_ptr->pcal_X1 = X1;
+   info_ptr->pcal_type = (png_byte)type;
+   info_ptr->pcal_nparams = (png_byte)nparams;
+
+   length = png_strlen(units) + 1;
+   png_debug1(3, "allocating units for info (%lu bytes)\n", length);
+   info_ptr->pcal_units = (png_charp)png_malloc_warn(png_ptr, length);
+   if (info_ptr->pcal_units == NULL)
+     {
+       png_warning(png_ptr, "Insufficient memory for pCAL units.");
+       return;
+     }
+   png_memcpy(info_ptr->pcal_units, units, (png_size_t)length);
+
+   info_ptr->pcal_params = (png_charpp)png_malloc_warn(png_ptr,
+      (png_uint_32)((nparams + 1) * png_sizeof(png_charp)));
+   if (info_ptr->pcal_params == NULL)
+     {
+       png_warning(png_ptr, "Insufficient memory for pCAL params.");
+       return;
+     }
+
+   info_ptr->pcal_params[nparams] = NULL;
+
+   for (i = 0; i < nparams; i++)
+   {
+      length = png_strlen(params[i]) + 1;
+      png_debug2(3, "allocating parameter %d for info (%lu bytes)\n", i, length);
+      info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
+      if (info_ptr->pcal_params[i] == NULL)
+        {
+          png_warning(png_ptr, "Insufficient memory for pCAL parameter.");
+          return;
+        }
+      png_memcpy(info_ptr->pcal_params[i], params[i], (png_size_t)length);
+   }
+
+   info_ptr->valid |= PNG_INFO_pCAL;
+#ifdef PNG_FREE_ME_SUPPORTED
+   info_ptr->free_me |= PNG_FREE_PCAL;
+#endif
+}
+#endif
+
+#if defined(PNG_READ_sCAL_SUPPORTED) || defined(PNG_WRITE_sCAL_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_sCAL(png_structp png_ptr, png_infop info_ptr,
+             int unit, double width, double height)
+{
+   png_debug1(1, "in %s storage function\n", "sCAL");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->scal_unit = (png_byte)unit;
+   info_ptr->scal_pixel_width = width;
+   info_ptr->scal_pixel_height = height;
+
+   info_ptr->valid |= PNG_INFO_sCAL;
+}
+#else
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void PNGAPI
+png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,
+             int unit, png_charp swidth, png_charp sheight)
+{
+   png_uint_32 length;
+
+   png_debug1(1, "in %s storage function\n", "sCAL");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->scal_unit = (png_byte)unit;
+
+   length = png_strlen(swidth) + 1;
+   png_debug1(3, "allocating unit for info (%d bytes)\n", length);
+   info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, length);
+   if (info_ptr->scal_s_width == NULL)
+   {
+      png_warning(png_ptr,
+       "Memory allocation failed while processing sCAL.");
+      return;
+   }
+   png_memcpy(info_ptr->scal_s_width, swidth, (png_size_t)length);
+
+   length = png_strlen(sheight) + 1;
+   png_debug1(3, "allocating unit for info (%d bytes)\n", length);
+   info_ptr->scal_s_height = (png_charp)png_malloc_warn(png_ptr, length);
+   if (info_ptr->scal_s_height == NULL)
+   {
+      png_free (png_ptr, info_ptr->scal_s_width);
+      png_warning(png_ptr,
+       "Memory allocation failed while processing sCAL.");
+      return;
+   }
+   png_memcpy(info_ptr->scal_s_height, sheight, (png_size_t)length);
+   info_ptr->valid |= PNG_INFO_sCAL;
+#ifdef PNG_FREE_ME_SUPPORTED
+   info_ptr->free_me |= PNG_FREE_SCAL;
+#endif
+}
+#endif
+#endif
+#endif
+
+#if defined(PNG_pHYs_SUPPORTED)
+void PNGAPI
+png_set_pHYs(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 res_x, png_uint_32 res_y, int unit_type)
+{
+   png_debug1(1, "in %s storage function\n", "pHYs");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->x_pixels_per_unit = res_x;
+   info_ptr->y_pixels_per_unit = res_y;
+   info_ptr->phys_unit_type = (png_byte)unit_type;
+   info_ptr->valid |= PNG_INFO_pHYs;
+}
+#endif
+
+void PNGAPI
+png_set_PLTE(png_structp png_ptr, png_infop info_ptr,
+   png_colorp palette, int num_palette)
+{
+
+   png_debug1(1, "in %s storage function\n", "PLTE");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
+     {
+       if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+         png_error(png_ptr, "Invalid palette length");
+       else
+       {
+         png_warning(png_ptr, "Invalid palette length");
+         return;
+       }
+     }
+
+   /*
+    * It may not actually be necessary to set png_ptr->palette here;
+    * we do it for backward compatibility with the way the png_handle_tRNS
+    * function used to do the allocation.
+    */
+#ifdef PNG_FREE_ME_SUPPORTED
+   png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
+#endif
+
+   /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
+      of num_palette entries,
+      in case of an invalid PNG file that has too-large sample values. */
+   png_ptr->palette = (png_colorp)png_malloc(png_ptr,
+      PNG_MAX_PALETTE_LENGTH * png_sizeof(png_color));
+   png_memset(png_ptr->palette, 0, PNG_MAX_PALETTE_LENGTH *
+      png_sizeof(png_color));
+   png_memcpy(png_ptr->palette, palette, num_palette * png_sizeof (png_color));
+   info_ptr->palette = png_ptr->palette;
+   info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
+
+#ifdef PNG_FREE_ME_SUPPORTED
+   info_ptr->free_me |= PNG_FREE_PLTE;
+#else
+   png_ptr->flags |= PNG_FLAG_FREE_PLTE;
+#endif
+
+   info_ptr->valid |= PNG_INFO_PLTE;
+}
+
+#if defined(PNG_sBIT_SUPPORTED)
+void PNGAPI
+png_set_sBIT(png_structp png_ptr, png_infop info_ptr,
+   png_color_8p sig_bit)
+{
+   png_debug1(1, "in %s storage function\n", "sBIT");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_memcpy(&(info_ptr->sig_bit), sig_bit, png_sizeof (png_color_8));
+   info_ptr->valid |= PNG_INFO_sBIT;
+}
+#endif
+
+#if defined(PNG_sRGB_SUPPORTED)
+void PNGAPI
+png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int intent)
+{
+   png_debug1(1, "in %s storage function\n", "sRGB");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->srgb_intent = (png_byte)intent;
+   info_ptr->valid |= PNG_INFO_sRGB;
+}
+
+void PNGAPI
+png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
+   int intent)
+{
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   float file_gamma;
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   png_fixed_point int_file_gamma;
+#endif
+#endif
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   png_fixed_point int_white_x, int_white_y, int_red_x, int_red_y, int_green_x,
+      int_green_y, int_blue_x, int_blue_y;
+#endif
+#endif
+   png_debug1(1, "in %s storage function\n", "sRGB_gAMA_and_cHRM");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_set_sRGB(png_ptr, info_ptr, intent);
+
+#if defined(PNG_gAMA_SUPPORTED)
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   file_gamma = (float).45455;
+   png_set_gAMA(png_ptr, info_ptr, file_gamma);
+#endif
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   int_file_gamma = 45455L;
+   png_set_gAMA_fixed(png_ptr, info_ptr, int_file_gamma);
+#endif
+#endif
+
+#if defined(PNG_cHRM_SUPPORTED)
+#ifdef PNG_FIXED_POINT_SUPPORTED
+   int_white_x = 31270L;
+   int_white_y = 32900L;
+   int_red_x   = 64000L;
+   int_red_y   = 33000L;
+   int_green_x = 30000L;
+   int_green_y = 60000L;
+   int_blue_x  = 15000L;
+   int_blue_y  =  6000L;
+
+   png_set_cHRM_fixed(png_ptr, info_ptr,
+      int_white_x, int_white_y, int_red_x, int_red_y, int_green_x, int_green_y,
+      int_blue_x, int_blue_y);
+#endif
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+   white_x = (float).3127;
+   white_y = (float).3290;
+   red_x   = (float).64;
+   red_y   = (float).33;
+   green_x = (float).30;
+   green_y = (float).60;
+   blue_x  = (float).15;
+   blue_y  = (float).06;
+
+   png_set_cHRM(png_ptr, info_ptr,
+      white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
+#endif
+#endif
+}
+#endif
+
+
+#if defined(PNG_iCCP_SUPPORTED)
+void PNGAPI
+png_set_iCCP(png_structp png_ptr, png_infop info_ptr,
+             png_charp name, int compression_type,
+             png_charp profile, png_uint_32 proflen)
+{
+   png_charp new_iccp_name;
+   png_charp new_iccp_profile;
+   png_uint_32 length;
+
+   png_debug1(1, "in %s storage function\n", "iCCP");
+   if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
+      return;
+
+   length = png_strlen(name)+1;
+   new_iccp_name = (png_charp)png_malloc_warn(png_ptr, length);
+   if (new_iccp_name == NULL)
+   {
+      png_warning(png_ptr, "Insufficient memory to process iCCP chunk.");
+      return;
+   }
+   png_memcpy(new_iccp_name, name, length);
+   new_iccp_profile = (png_charp)png_malloc_warn(png_ptr, proflen);
+   if (new_iccp_profile == NULL)
+   {
+      png_free (png_ptr, new_iccp_name);
+      png_warning(png_ptr, "Insufficient memory to process iCCP profile.");
+      return;
+   }
+   png_memcpy(new_iccp_profile, profile, (png_size_t)proflen);
+
+   png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
+
+   info_ptr->iccp_proflen = proflen;
+   info_ptr->iccp_name = new_iccp_name;
+   info_ptr->iccp_profile = new_iccp_profile;
+   /* Compression is always zero but is here so the API and info structure
+    * does not have to change if we introduce multiple compression types */
+   info_ptr->iccp_compression = (png_byte)compression_type;
+#ifdef PNG_FREE_ME_SUPPORTED
+   info_ptr->free_me |= PNG_FREE_ICCP;
+#endif
+   info_ptr->valid |= PNG_INFO_iCCP;
+}
+#endif
+
+#if defined(PNG_TEXT_SUPPORTED)
+void PNGAPI
+png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
+   int num_text)
+{
+   int ret;
+   ret=png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
+   if (ret)
+     png_error(png_ptr, "Insufficient memory to store text");
+}
+
+int /* PRIVATE */
+png_set_text_2(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
+   int num_text)
+{
+   int i;
+
+   png_debug1(1, "in %s storage function\n", (png_ptr->chunk_name[0] == '\0' ?
+      "text" : (png_const_charp)png_ptr->chunk_name));
+
+   if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
+      return(0);
+
+   /* Make sure we have enough space in the "text" array in info_struct
+    * to hold all of the incoming text_ptr objects.
+    */
+   if (info_ptr->num_text + num_text > info_ptr->max_text)
+   {
+      if (info_ptr->text != NULL)
+      {
+         png_textp old_text;
+         int old_max;
+
+         old_max = info_ptr->max_text;
+         info_ptr->max_text = info_ptr->num_text + num_text + 8;
+         old_text = info_ptr->text;
+         info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
+            (png_uint_32)(info_ptr->max_text * png_sizeof (png_text)));
+         if (info_ptr->text == NULL)
+           {
+             png_free(png_ptr, old_text);
+             return(1);
+           }
+         png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
+            png_sizeof(png_text)));
+         png_free(png_ptr, old_text);
+      }
+      else
+      {
+         info_ptr->max_text = num_text + 8;
+         info_ptr->num_text = 0;
+         info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
+            (png_uint_32)(info_ptr->max_text * png_sizeof (png_text)));
+         if (info_ptr->text == NULL)
+           return(1);
+#ifdef PNG_FREE_ME_SUPPORTED
+         info_ptr->free_me |= PNG_FREE_TEXT;
+#endif
+      }
+      png_debug1(3, "allocated %d entries for info_ptr->text\n",
+         info_ptr->max_text);
+   }
+   for (i = 0; i < num_text; i++)
+   {
+      png_size_t text_length,key_len;
+      png_size_t lang_len,lang_key_len;
+      png_textp textp = &(info_ptr->text[info_ptr->num_text]);
+
+      if (text_ptr[i].key == NULL)
+          continue;
+
+      key_len = png_strlen(text_ptr[i].key);
+
+      if(text_ptr[i].compression <= 0)
+      {
+        lang_len = 0;
+        lang_key_len = 0;
+      }
+      else
+#ifdef PNG_iTXt_SUPPORTED
+      {
+        /* set iTXt data */
+        if (text_ptr[i].lang != NULL)
+          lang_len = png_strlen(text_ptr[i].lang);
+        else
+          lang_len = 0;
+        if (text_ptr[i].lang_key != NULL)
+          lang_key_len = png_strlen(text_ptr[i].lang_key);
+        else
+          lang_key_len = 0;
+      }
+#else
+      {
+        png_warning(png_ptr, "iTXt chunk not supported.");
+        continue;
+      }
+#endif
+
+      if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
+      {
+         text_length = 0;
+#ifdef PNG_iTXt_SUPPORTED
+         if(text_ptr[i].compression > 0)
+            textp->compression = PNG_ITXT_COMPRESSION_NONE;
+         else
+#endif
+            textp->compression = PNG_TEXT_COMPRESSION_NONE;
+      }
+      else
+      {
+         text_length = png_strlen(text_ptr[i].text);
+         textp->compression = text_ptr[i].compression;
+      }
+
+      textp->key = (png_charp)png_malloc_warn(png_ptr,
+         (png_uint_32)(key_len + text_length + lang_len + lang_key_len + 4));
+      if (textp->key == NULL)
+        return(1);
+      png_debug2(2, "Allocated %lu bytes at %x in png_set_text\n",
+         (png_uint_32)(key_len + lang_len + lang_key_len + text_length + 4),
+         (int)textp->key);
+
+      png_memcpy(textp->key, text_ptr[i].key,
+         (png_size_t)(key_len));
+      *(textp->key+key_len) = '\0';
+#ifdef PNG_iTXt_SUPPORTED
+      if (text_ptr[i].compression > 0)
+      {
+         textp->lang=textp->key + key_len + 1;
+         png_memcpy(textp->lang, text_ptr[i].lang, lang_len);
+         *(textp->lang+lang_len) = '\0';
+         textp->lang_key=textp->lang + lang_len + 1;
+         png_memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
+         *(textp->lang_key+lang_key_len) = '\0';
+         textp->text=textp->lang_key + lang_key_len + 1;
+      }
+      else
+#endif
+      {
+#ifdef PNG_iTXt_SUPPORTED
+         textp->lang=NULL;
+         textp->lang_key=NULL;
+#endif
+         textp->text=textp->key + key_len + 1;
+      }
+      if(text_length)
+         png_memcpy(textp->text, text_ptr[i].text,
+            (png_size_t)(text_length));
+      *(textp->text+text_length) = '\0';
+
+#ifdef PNG_iTXt_SUPPORTED
+      if(textp->compression > 0)
+      {
+         textp->text_length = 0;
+         textp->itxt_length = text_length;
+      }
+      else
+#endif
+      {
+         textp->text_length = text_length;
+#ifdef PNG_iTXt_SUPPORTED
+         textp->itxt_length = 0;
+#endif
+      }
+      info_ptr->num_text++;
+      png_debug1(3, "transferred text chunk %d\n", info_ptr->num_text);
+   }
+   return(0);
+}
+#endif
+
+#if defined(PNG_tIME_SUPPORTED)
+void PNGAPI
+png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_timep mod_time)
+{
+   png_debug1(1, "in %s storage function\n", "tIME");
+   if (png_ptr == NULL || info_ptr == NULL ||
+       (png_ptr->mode & PNG_WROTE_tIME))
+      return;
+
+   png_memcpy(&(info_ptr->mod_time), mod_time, png_sizeof (png_time));
+   info_ptr->valid |= PNG_INFO_tIME;
+}
+#endif
+
+#if defined(PNG_tRNS_SUPPORTED)
+void PNGAPI
+png_set_tRNS(png_structp png_ptr, png_infop info_ptr,
+   png_bytep trans, int num_trans, png_color_16p trans_values)
+{
+   png_debug1(1, "in %s storage function\n", "tRNS");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
+
+   if (trans != NULL)
+   {
+       /*
+        * It may not actually be necessary to set png_ptr->trans here;
+        * we do it for backward compatibility with the way the png_handle_tRNS
+        * function used to do the allocation.
+        */
+
+       /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
+       png_ptr->trans = info_ptr->trans = (png_bytep)png_malloc(png_ptr,
+           (png_uint_32)PNG_MAX_PALETTE_LENGTH);
+       if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
+         png_memcpy(info_ptr->trans, trans, (png_size_t)num_trans);
+   }
+
+   if (trans_values != NULL)
+   {
+      int sample_max = (1 << info_ptr->bit_depth);
+      if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
+          (int)trans_values->gray > sample_max) ||
+          (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
+          ((int)trans_values->red > sample_max ||
+          (int)trans_values->green > sample_max ||
+          (int)trans_values->blue > sample_max)))
+        png_warning(png_ptr,
+           "tRNS chunk has out-of-range samples for bit_depth");
+      png_memcpy(&(info_ptr->trans_values), trans_values,
+         png_sizeof(png_color_16));
+      if (num_trans == 0)
+        num_trans = 1;
+   }
+
+   info_ptr->num_trans = (png_uint_16)num_trans;
+   if (num_trans != 0)
+   {
+      info_ptr->valid |= PNG_INFO_tRNS;
+#ifdef PNG_FREE_ME_SUPPORTED
+      info_ptr->free_me |= PNG_FREE_TRNS;
+#else
+      png_ptr->flags |= PNG_FLAG_FREE_TRNS;
+#endif
+   }
+}
+#endif
+
+#if defined(PNG_sPLT_SUPPORTED)
+void PNGAPI
+png_set_sPLT(png_structp png_ptr,
+             png_infop info_ptr, png_sPLT_tp entries, int nentries)
+{
+    png_sPLT_tp np;
+    int i;
+
+    if (png_ptr == NULL || info_ptr == NULL)
+       return;
+
+    np = (png_sPLT_tp)png_malloc_warn(png_ptr,
+        (info_ptr->splt_palettes_num + nentries) * png_sizeof(png_sPLT_t));
+    if (np == NULL)
+    {
+      png_warning(png_ptr, "No memory for sPLT palettes.");
+      return;
+    }
+
+    png_memcpy(np, info_ptr->splt_palettes,
+           info_ptr->splt_palettes_num * png_sizeof(png_sPLT_t));
+    png_free(png_ptr, info_ptr->splt_palettes);
+    info_ptr->splt_palettes=NULL;
+
+    for (i = 0; i < nentries; i++)
+    {
+        png_sPLT_tp to = np + info_ptr->splt_palettes_num + i;
+        png_sPLT_tp from = entries + i;
+        png_uint_32 length;
+
+        length = png_strlen(from->name) + 1;
+        to->name = (png_charp)png_malloc_warn(png_ptr, length);
+        if (to->name == NULL)
+        {
+           png_warning(png_ptr,
+             "Out of memory while processing sPLT chunk");
+           continue;
+        }
+        png_memcpy(to->name, from->name, length);
+        to->entries = (png_sPLT_entryp)png_malloc_warn(png_ptr,
+            from->nentries * png_sizeof(png_sPLT_entry));
+        if (to->entries == NULL)
+        {
+           png_warning(png_ptr,
+             "Out of memory while processing sPLT chunk");
+           png_free(png_ptr,to->name);
+           to->name = NULL;
+           continue;
+        }
+        png_memcpy(to->entries, from->entries,
+            from->nentries * png_sizeof(png_sPLT_entry));
+        to->nentries = from->nentries;
+        to->depth = from->depth;
+    }
+
+    info_ptr->splt_palettes = np;
+    info_ptr->splt_palettes_num += nentries;
+    info_ptr->valid |= PNG_INFO_sPLT;
+#ifdef PNG_FREE_ME_SUPPORTED
+    info_ptr->free_me |= PNG_FREE_SPLT;
+#endif
+}
+#endif /* PNG_sPLT_SUPPORTED */
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+void PNGAPI
+png_set_unknown_chunks(png_structp png_ptr,
+   png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns)
+{
+    png_unknown_chunkp np;
+    int i;
+
+    if (png_ptr == NULL || info_ptr == NULL || num_unknowns == 0)
+        return;
+
+    np = (png_unknown_chunkp)png_malloc_warn(png_ptr,
+        (info_ptr->unknown_chunks_num + num_unknowns) *
+        png_sizeof(png_unknown_chunk));
+    if (np == NULL)
+    {
+       png_warning(png_ptr,
+          "Out of memory while processing unknown chunk.");
+       return;
+    }
+
+    png_memcpy(np, info_ptr->unknown_chunks,
+           info_ptr->unknown_chunks_num * png_sizeof(png_unknown_chunk));
+    png_free(png_ptr, info_ptr->unknown_chunks);
+    info_ptr->unknown_chunks=NULL;
+
+    for (i = 0; i < num_unknowns; i++)
+    {
+       png_unknown_chunkp to = np + info_ptr->unknown_chunks_num + i;
+       png_unknown_chunkp from = unknowns + i;
+
+       png_memcpy((png_charp)to->name, 
+                  (png_charp)from->name, 
+                  png_sizeof(from->name));
+       to->name[png_sizeof(to->name)-1] = '\0';
+       to->size = from->size;
+       /* note our location in the read or write sequence */
+       to->location = (png_byte)(png_ptr->mode & 0xff);
+
+       if (from->size == 0)
+          to->data=NULL;
+       else
+       {
+          to->data = (png_bytep)png_malloc_warn(png_ptr, from->size);
+          if (to->data == NULL)
+          {
+             png_warning(png_ptr,
+              "Out of memory while processing unknown chunk.");
+             to->size=0;
+          }
+          else
+             png_memcpy(to->data, from->data, from->size);
+       }
+    }
+
+    info_ptr->unknown_chunks = np;
+    info_ptr->unknown_chunks_num += num_unknowns;
+#ifdef PNG_FREE_ME_SUPPORTED
+    info_ptr->free_me |= PNG_FREE_UNKN;
+#endif
+}
+void PNGAPI
+png_set_unknown_chunk_location(png_structp png_ptr, png_infop info_ptr,
+   int chunk, int location)
+{
+   if(png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk <
+         (int)info_ptr->unknown_chunks_num)
+      info_ptr->unknown_chunks[chunk].location = (png_byte)location;
+}
+#endif
+
+#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
+#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
+    defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
+void PNGAPI
+png_permit_empty_plte (png_structp png_ptr, int empty_plte_permitted)
+{
+   /* This function is deprecated in favor of png_permit_mng_features()
+      and will be removed from libpng-1.3.0 */
+   png_debug(1, "in png_permit_empty_plte, DEPRECATED.\n");
+   if (png_ptr == NULL)
+      return;
+   png_ptr->mng_features_permitted = (png_byte)
+     ((png_ptr->mng_features_permitted & (~PNG_FLAG_MNG_EMPTY_PLTE)) |
+     ((empty_plte_permitted & PNG_FLAG_MNG_EMPTY_PLTE)));
+}
+#endif
+#endif
+
+#if defined(PNG_MNG_FEATURES_SUPPORTED)
+png_uint_32 PNGAPI
+png_permit_mng_features (png_structp png_ptr, png_uint_32 mng_features)
+{
+   png_debug(1, "in png_permit_mng_features\n");
+   if (png_ptr == NULL)
+      return (png_uint_32)0;
+   png_ptr->mng_features_permitted =
+     (png_byte)(mng_features & PNG_ALL_MNG_FEATURES);
+   return (png_uint_32)png_ptr->mng_features_permitted;
+}
+#endif
+
+#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+void PNGAPI
+png_set_keep_unknown_chunks(png_structp png_ptr, int keep, png_bytep
+   chunk_list, int num_chunks)
+{
+    png_bytep new_list, p;
+    int i, old_num_chunks;
+    if (png_ptr == NULL)
+       return;
+    if (num_chunks == 0)
+    {
+      if(keep == PNG_HANDLE_CHUNK_ALWAYS || keep == PNG_HANDLE_CHUNK_IF_SAFE)
+        png_ptr->flags |= PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
+      else
+        png_ptr->flags &= ~PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
+
+      if(keep == PNG_HANDLE_CHUNK_ALWAYS)
+        png_ptr->flags |= PNG_FLAG_KEEP_UNSAFE_CHUNKS;
+      else
+        png_ptr->flags &= ~PNG_FLAG_KEEP_UNSAFE_CHUNKS;
+      return;
+    }
+    if (chunk_list == NULL)
+      return;
+    old_num_chunks=png_ptr->num_chunk_list;
+    new_list=(png_bytep)png_malloc(png_ptr,
+       (png_uint_32)(5*(num_chunks+old_num_chunks)));
+    if(png_ptr->chunk_list != NULL)
+    {
+       png_memcpy(new_list, png_ptr->chunk_list,
+          (png_size_t)(5*old_num_chunks));
+       png_free(png_ptr, png_ptr->chunk_list);
+       png_ptr->chunk_list=NULL;
+    }
+    png_memcpy(new_list+5*old_num_chunks, chunk_list,
+       (png_size_t)(5*num_chunks));
+    for (p=new_list+5*old_num_chunks+4, i=0; i<num_chunks; i++, p+=5)
+       *p=(png_byte)keep;
+    png_ptr->num_chunk_list=old_num_chunks+num_chunks;
+    png_ptr->chunk_list=new_list;
+#ifdef PNG_FREE_ME_SUPPORTED
+    png_ptr->free_me |= PNG_FREE_LIST;
+#endif
+}
+#endif
+
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+void PNGAPI
+png_set_read_user_chunk_fn(png_structp png_ptr, png_voidp user_chunk_ptr,
+   png_user_chunk_ptr read_user_chunk_fn)
+{
+   png_debug(1, "in png_set_read_user_chunk_fn\n");
+   if (png_ptr == NULL)
+      return;
+   png_ptr->read_user_chunk_fn = read_user_chunk_fn;
+   png_ptr->user_chunk_ptr = user_chunk_ptr;
+}
+#endif
+
+#if defined(PNG_INFO_IMAGE_SUPPORTED)
+void PNGAPI
+png_set_rows(png_structp png_ptr, png_infop info_ptr, png_bytepp row_pointers)
+{
+   png_debug1(1, "in %s storage function\n", "rows");
+
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if(info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
+      png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
+   info_ptr->row_pointers = row_pointers;
+   if(row_pointers)
+      info_ptr->valid |= PNG_INFO_IDAT;
+}
+#endif
+
+#ifdef PNG_WRITE_SUPPORTED
+void PNGAPI
+png_set_compression_buffer_size(png_structp png_ptr, png_uint_32 size)
+{
+    if (png_ptr == NULL)
+       return;
+    png_free(png_ptr, png_ptr->zbuf);
+    png_ptr->zbuf_size = (png_size_t)size;
+    png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, size);
+    png_ptr->zstream.next_out = png_ptr->zbuf;
+    png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+}
+#endif
+
+void PNGAPI
+png_set_invalid(png_structp png_ptr, png_infop info_ptr, int mask)
+{
+   if (png_ptr && info_ptr)
+      info_ptr->valid &= ~mask;
+}
+
+
+#ifndef PNG_1_0_X
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+/* function was added to libpng 1.2.0 and should always exist by default */
+void PNGAPI
+png_set_asm_flags (png_structp png_ptr, png_uint_32 asm_flags)
+{
+/* Obsolete as of libpng-1.2.20 and will be removed from libpng-1.4.0 */
+    if (png_ptr != NULL)
+    png_ptr->asm_flags = 0;
+}
+
+/* this function was added to libpng 1.2.0 */
+void PNGAPI
+png_set_mmx_thresholds (png_structp png_ptr,
+                        png_byte mmx_bitdepth_threshold,
+                        png_uint_32 mmx_rowbytes_threshold)
+{
+/* Obsolete as of libpng-1.2.20 and will be removed from libpng-1.4.0 */
+    if (png_ptr == NULL)
+       return;
+}
+#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+/* this function was added to libpng 1.2.6 */
+void PNGAPI
+png_set_user_limits (png_structp png_ptr, png_uint_32 user_width_max,
+    png_uint_32 user_height_max)
+{
+    /* Images with dimensions larger than these limits will be
+     * rejected by png_set_IHDR().  To accept any PNG datastream
+     * regardless of dimensions, set both limits to 0x7ffffffL.
+     */
+    if(png_ptr == NULL) return;
+    png_ptr->user_width_max = user_width_max;
+    png_ptr->user_height_max = user_height_max;
+}
+#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
+
+#endif /* ?PNG_1_0_X */
+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */