libpng: update to 1.2.43

third_party/libpng/pngrutil.c

 
 /* pngrutil.c - utilities to read a PNG file
  *
- * Last changed in libpng 1.2.37 [June 4, 2009]
- * For conditions of distribution and use, see copyright notice in png.h
+ * Last changed in libpng 1.2.43 [February 25, 2010]
  * Copyright (c) 1998-2009 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.)
  *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
  * This file contains routines that are only called from within
  * libpng itself during the course of reading an image.
  */
 
 #define PNG_INTERNAL
+#define PNG_NO_PEDANTIC_WARNINGS
 #include "png.h"
-#if defined(PNG_READ_SUPPORTED)
+#ifdef PNG_READ_SUPPORTED
 
 #if defined(_WIN32_WCE) && (_WIN32_WCE<0x500)
 #  define WIN32_WCE_OLD
 #endif
 
 #ifdef PNG_FLOATING_POINT_SUPPORTED
-#  if defined(WIN32_WCE_OLD)
+#  ifdef WIN32_WCE_OLD
 /* The strtod() function is not supported on WindowsCE */
-__inline double png_strtod(png_structp png_ptr, PNG_CONST char *nptr, char **endptr)
+__inline double png_strtod(png_structp png_ptr, PNG_CONST char *nptr,
+    char **endptr)
 {
    double result = 0;
    int len;
    wchar_t *str, *end;
 
    len = MultiByteToWideChar(CP_ACP, 0, nptr, -1, NULL, 0);
    str = (wchar_t *)png_malloc(png_ptr, len * png_sizeof(wchar_t));
    if ( NULL != str )
    {
       MultiByteToWideChar(CP_ACP, 0, nptr, -1, str, len);
@@ skipping 170 matching lines @@
    {
       crc = png_get_uint_32(crc_bytes);
       return ((int)(crc != png_ptr->crc));
    }
    else
       return (0);
 }
 
 #if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) || \
     defined(PNG_READ_iCCP_SUPPORTED)
+static png_size_t
+png_inflate(png_structp png_ptr, const png_byte *data, png_size_t size,
+        png_bytep output, png_size_t output_size)
+{
+   png_size_t count = 0;
+
+   png_ptr->zstream.next_in = (png_bytep)data; /* const_cast: VALID */
+   png_ptr->zstream.avail_in = size;
+
+   while (1)
+   {
+      int ret, avail;
+
+      /* Reset the output buffer each time round - we empty it
+       * after every inflate call.
+       */
+      png_ptr->zstream.next_out = png_ptr->zbuf;
+      png_ptr->zstream.avail_out = png_ptr->zbuf_size;
+
+      ret = inflate(&png_ptr->zstream, Z_NO_FLUSH);
+      avail = png_ptr->zbuf_size - png_ptr->zstream.avail_out;
+
+      /* First copy/count any new output - but only if we didn't
+       * get an error code.
+       */
+      if ((ret == Z_OK || ret == Z_STREAM_END) && avail > 0)
+      {
+         if (output != 0 && output_size > count)
+         {
+            int copy = output_size - count;
+            if (avail < copy) copy = avail;
+            png_memcpy(output + count, png_ptr->zbuf, copy);
+         }
+         count += avail;
+      }
+
+      if (ret == Z_OK)
+         continue;
+
+      /* Termination conditions - always reset the zstream, it
+       * must be left in inflateInit state.
+       */
+      png_ptr->zstream.avail_in = 0;
+      inflateReset(&png_ptr->zstream);
+
+      if (ret == Z_STREAM_END)
+         return count; /* NOTE: may be zero. */
+
+      /* Now handle the error codes - the API always returns 0
+       * and the error message is dumped into the uncompressed
+       * buffer if available.
+       */
+      {
+         char *msg, umsg[52];
+         if (png_ptr->zstream.msg != 0)
+            msg = png_ptr->zstream.msg;
+         else
+         {
+#if defined(PNG_STDIO_SUPPORTED) && !defined(_WIN32_WCE)
+            switch (ret)
+            {
+         case Z_BUF_ERROR:
+            msg = "Buffer error in compressed datastream in %s chunk";
+            break;
+         case Z_DATA_ERROR:
+            msg = "Data error in compressed datastream in %s chunk";
+            break;
+         default:
+            msg = "Incomplete compressed datastream in %s chunk";
+            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);
+      }
+
+      /* 0 means an error - notice that this code simple ignores
+       * zero length compressed chunks as a result.
+       */
+      return 0;
+   }
+}
+
 /*
  * Decompress trailing data in a chunk.  The assumption is that chunkdata
  * points at an allocated area holding the contents of a chunk with a
  * trailing compressed part.  What we get back is an allocated area
  * holding the original prefix part and an uncompressed version of the
  * trailing part (the malloc area passed in is freed).
  */
 void /* PRIVATE */
 png_decompress_chunk(png_structp png_ptr, int comp_type,
-                              png_size_t chunklength,
-                              png_size_t prefix_size, png_size_t *newlength)
+    png_size_t chunklength,
+    png_size_t prefix_size, png_size_t *newlength)
 {
-   static PNG_CONST char msg[] = "Error decoding compressed text";
-   png_charp text;
-   png_size_t text_size;
-
-   if (comp_type == PNG_COMPRESSION_TYPE_BASE)
-   {
-      int ret = Z_OK;
-      png_ptr->zstream.next_in = (png_bytep)(png_ptr->chunkdata + prefix_size);
-      png_ptr->zstream.avail_in = (uInt)(chunklength - prefix_size);
-      png_ptr->zstream.next_out = png_ptr->zbuf;
-      png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
-
-      text_size = 0;
-      text = NULL;
-
-      while (png_ptr->zstream.avail_in)
-      {
-         ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
-         if (ret != Z_OK && ret != Z_STREAM_END)
+   /* The caller should guarantee this */
+   if (prefix_size > chunklength)
+   {
+      /* The recovery is to delete the chunk. */
+      png_warning(png_ptr, "invalid chunklength");
+      prefix_size = 0; /* To delete everything */
+   }
+
+   else if (comp_type == PNG_COMPRESSION_TYPE_BASE)
+   {
+      png_size_t expanded_size = png_inflate(png_ptr,
+                (png_bytep)(png_ptr->chunkdata + prefix_size),
+                chunklength - prefix_size,
+                0/*output*/, 0/*output size*/);

[SkyLined, 2010/03/18 16:34:46]

Seems to me like the code decompresses twice, once to determine the size of the
compressed data without storing the decompressed data and once after it
determines the size is within limits. This could cause a performance hit, do we
need to worry about that?

[agl, 2010/03/18 16:50:41]

I agree that this isn't great. It could probably be done better, but I think we
want the security fix so we should take this as is, and push a better solution
upstream.

+
+      /* Now check the limits on this chunk - if the limit fails the
+       * compressed data will be removed, the prefix will remain.
+       */
+#ifdef PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
+      if (png_ptr->user_chunk_malloc_max &&
+          (prefix_size + expanded_size >= png_ptr->user_chunk_malloc_max - 1))
+#else
+      if ((PNG_USER_CHUNK_MALLOC_MAX > 0) &&
+          prefix_size + expanded_size >= PNG_USER_CHUNK_MALLOC_MAX - 1)
+#endif
+         png_warning(png_ptr, "Exceeded size limit while expanding chunk");
+
+      /* If the size is zero either there was an error and a message
+       * has already been output (warning) or the size really is zero
+       * and we have nothing to do - the code will exit through the
+       * error case below.
+       */
+      else if (expanded_size > 0)
+      {
+         /* Success (maybe) - really uncompress the chunk. */
+         png_size_t new_size = 0;
+         png_charp text = png_malloc_warn(png_ptr,
+                        prefix_size + expanded_size + 1);
+
+         if (text != NULL)
          {
-            if (png_ptr->zstream.msg != NULL)
-               png_warning(png_ptr, png_ptr->zstream.msg);
-            else
-               png_warning(png_ptr, msg);
-            inflateReset(&png_ptr->zstream);
-            png_ptr->zstream.avail_in = 0;
-
-            if (text ==  NULL)
-            {
-               text_size = prefix_size + png_sizeof(msg) + 1;
-               text = (png_charp)png_malloc_warn(png_ptr, text_size);
-               if (text ==  NULL)
-                 {
-                    png_free(png_ptr, png_ptr->chunkdata);
-                    png_ptr->chunkdata = NULL;
-                    png_error(png_ptr, "Not enough memory to decompress chunk");
-                 }
-               png_memcpy(text, png_ptr->chunkdata, prefix_size);
-            }
-
-            text[text_size - 1] = 0x00;
-
-            /* Copy what we can of the error message into the text chunk */
-            text_size = (png_size_t)(chunklength -
-              (text - png_ptr->chunkdata) - 1);
-            if (text_size > png_sizeof(msg))
-               text_size = png_sizeof(msg);
-            png_memcpy(text + prefix_size, msg, text_size);
-            break;
-         }
-         if (!png_ptr->zstream.avail_out || ret == Z_STREAM_END)
-         {
-            if (text == NULL)
-            {
-               text_size = prefix_size +
-                   png_ptr->zbuf_size - png_ptr->zstream.avail_out;
-               text = (png_charp)png_malloc_warn(png_ptr, text_size + 1);
-               if (text ==  NULL)
-               {
-                  png_free(png_ptr, png_ptr->chunkdata);
-                  png_ptr->chunkdata = NULL;
-                  png_error(png_ptr,
-                    "Not enough memory to decompress chunk.");
-               }
-               png_memcpy(text + prefix_size, png_ptr->zbuf,
-                    text_size - prefix_size);
-               png_memcpy(text, png_ptr->chunkdata, prefix_size);
-               *(text + text_size) = 0x00;
-            }
-            else
-            {
-               png_charp tmp;
-
-               tmp = text;
-               text = (png_charp)png_malloc_warn(png_ptr,
-                  (png_uint_32)(text_size +
-                  png_ptr->zbuf_size - png_ptr->zstream.avail_out + 1));
-               if (text == NULL)
-               {
-                  png_free(png_ptr, tmp);
-                  png_free(png_ptr, png_ptr->chunkdata);
-                  png_ptr->chunkdata = NULL;
-                  png_error(png_ptr,
-                    "Not enough memory to decompress chunk..");
-               }
-               png_memcpy(text, tmp, text_size);
-               png_free(png_ptr, tmp);
-               png_memcpy(text + text_size, png_ptr->zbuf,
-                  (png_ptr->zbuf_size - png_ptr->zstream.avail_out));
-               text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
-               *(text + text_size) = 0x00;
-            }
-            if (ret == Z_STREAM_END)
-               break;
-            else
-            {
-               png_ptr->zstream.next_out = png_ptr->zbuf;
-               png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
-            }
-         }
-      }
-      if (ret != Z_STREAM_END)
-      {
-#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
-         char umsg[52];
-
-         if (ret == Z_BUF_ERROR)
-            png_snprintf(umsg, 52,
-                "Buffer error in compressed datastream in %s chunk",
-                png_ptr->chunk_name);
-
-         else if (ret == Z_DATA_ERROR)
-            png_snprintf(umsg, 52,
-                "Data error in compressed datastream in %s chunk",
-                png_ptr->chunk_name);
-
-         else
-            png_snprintf(umsg, 52,
-                "Incomplete compressed datastream in %s chunk",
-                png_ptr->chunk_name);
-
-         png_warning(png_ptr, umsg);
-#else
-         png_warning(png_ptr,
-            "Incomplete compressed datastream in chunk other than IDAT");
-#endif
-         text_size = prefix_size;
-         if (text ==  NULL)
-         {
-            text = (png_charp)png_malloc_warn(png_ptr, text_size+1);
-            if (text == NULL)
-              {
-                png_free(png_ptr, png_ptr->chunkdata);
-                png_ptr->chunkdata = NULL;
-                png_error(png_ptr, "Not enough memory for text.");
-              }
-            png_memcpy(text, png_ptr->chunkdata, prefix_size);
-         }
-         *(text + text_size) = 0x00;
-      }
-
-      inflateReset(&png_ptr->zstream);
-      png_ptr->zstream.avail_in = 0;
-
-      png_free(png_ptr, png_ptr->chunkdata);
-      png_ptr->chunkdata = text;
-      *newlength=text_size;
-   }
+            png_memcpy(text, png_ptr->chunkdata, prefix_size);
+            new_size = png_inflate(png_ptr,
+                (png_bytep)(png_ptr->chunkdata + prefix_size),
+                chunklength - prefix_size,
+                (png_bytep)(text + prefix_size), expanded_size);
+            text[prefix_size + expanded_size] = 0; /* just in case */
+
+            if (new_size == expanded_size)
+            {
+               png_free(png_ptr, png_ptr->chunkdata);
+               png_ptr->chunkdata = text;
+               *newlength = prefix_size + expanded_size;
+               return; /* The success return! */
+            }
+      
+            png_warning(png_ptr, "png_inflate logic error");
+            png_free(png_ptr, text);
+         }
+         else
+          png_warning(png_ptr, "Not enough memory to decompress chunk.");
+      }
+   }
+
    else /* if (comp_type != PNG_COMPRESSION_TYPE_BASE) */
    {
-#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
       char umsg[50];
 
-      png_snprintf(umsg, 50, "Unknown zTXt compression type %d", comp_type);
+#if defined(PNG_STDIO_SUPPORTED) && !defined(_WIN32_WCE)
+      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
 
-      *(png_ptr->chunkdata + prefix_size) = 0x00;
-      *newlength = prefix_size;
-   }
+      /* The recovery is to simply drop the data. */
+   }
+
+   /* Generic error return - leave the prefix, delete the compressed
+    * data, reallocate the chunkdata to remove the potentially large
+    * amount of compressed data.
+    */
+   {
+      png_charp text = png_malloc_warn(png_ptr, prefix_size + 1);
+      if (text != NULL)
+      {
+         if (prefix_size > 0)
+            png_memcpy(text, png_ptr->chunkdata, prefix_size);
+         png_free(png_ptr, png_ptr->chunkdata);
+         png_ptr->chunkdata = text;
+
+         /* This is an extra zero in the 'uncompressed' part. */
+         *(png_ptr->chunkdata + prefix_size) = 0x00;
+      }
+      /* Ignore a malloc error here - it is safe. */
+   }
+
+   *newlength = prefix_size;
 }
 #endif
 
 /* Read and check the IDHR chunk */
 void /* PRIVATE */
 png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_byte buf[13];
    png_uint_32 width, height;
    int bit_depth, color_type, compression_type, filter_type;
@@ skipping 20 matching lines @@
    compression_type = buf[10];
    filter_type = buf[11];
    interlace_type = buf[12];
 
    /* Set internal variables */
    png_ptr->width = width;
    png_ptr->height = height;
    png_ptr->bit_depth = (png_byte)bit_depth;
    png_ptr->interlaced = (png_byte)interlace_type;
    png_ptr->color_type = (png_byte)color_type;
-#if defined(PNG_MNG_FEATURES_SUPPORTED)
+#ifdef PNG_MNG_FEATURES_SUPPORTED
    png_ptr->filter_type = (png_byte)filter_type;
 #endif
    png_ptr->compression_type = (png_byte)compression_type;
 
    /* Find number of channels */
    switch (png_ptr->color_type)
    {
       case PNG_COLOR_TYPE_GRAY:
       case PNG_COLOR_TYPE_PALETTE:
          png_ptr->channels = 1;
@@ skipping 22 matching lines @@
    png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth,
       color_type, interlace_type, compression_type, filter_type);
 }
 
 /* Read and check the palette */
 void /* PRIVATE */
 png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_color palette[PNG_MAX_PALETTE_LENGTH];
    int num, i;
-#ifndef PNG_NO_POINTER_INDEXING
+#ifdef PNG_POINTER_INDEXING_SUPPORTED
    png_colorp pal_ptr;
 #endif
 
    png_debug(1, "in png_handle_PLTE");
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before PLTE");
 
    else if (png_ptr->mode & PNG_HAVE_IDAT)
    {
       png_warning(png_ptr, "Invalid PLTE after IDAT");
       png_crc_finish(png_ptr, length);
       return;
    }
 
    else if (png_ptr->mode & PNG_HAVE_PLTE)
       png_error(png_ptr, "Duplicate PLTE chunk");
 
    png_ptr->mode |= PNG_HAVE_PLTE;
 
    if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))
    {
       png_warning(png_ptr,
         "Ignoring PLTE chunk in grayscale PNG");
       png_crc_finish(png_ptr, length);
       return;
    }
-#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
+#ifndef PNG_READ_OPT_PLTE_SUPPORTED
    if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
    {
       png_crc_finish(png_ptr, length);
       return;
    }
 #endif
 
    if (length > 3*PNG_MAX_PALETTE_LENGTH || length % 3)
    {
       if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
       {
          png_warning(png_ptr, "Invalid palette chunk");
          png_crc_finish(png_ptr, length);
          return;
       }
 
       else
       {
          png_error(png_ptr, "Invalid palette chunk");
       }
    }
 
    num = (int)length / 3;
 
-#ifndef PNG_NO_POINTER_INDEXING
+#ifdef PNG_POINTER_INDEXING_SUPPORTED
    for (i = 0, pal_ptr = palette; i < num; i++, pal_ptr++)
    {
       png_byte buf[3];
 
       png_crc_read(png_ptr, buf, 3);
       pal_ptr->red = buf[0];
       pal_ptr->green = buf[1];
       pal_ptr->blue = buf[2];
    }
 #else
    for (i = 0; i < num; i++)
    {
       png_byte buf[3];
 
       png_crc_read(png_ptr, buf, 3);
       /* Don't depend upon png_color being any order */
       palette[i].red = buf[0];
       palette[i].green = buf[1];
       palette[i].blue = buf[2];
    }
 #endif
 
    /* If we actually NEED the PLTE chunk (ie for a paletted image), we do
     * whatever the normal CRC configuration tells us.  However, if we
     * have an RGB image, the PLTE can be considered ancillary, so
     * we will act as though it is.
     */
-#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
+#ifndef PNG_READ_OPT_PLTE_SUPPORTED
    if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
 #endif
    {
       png_crc_finish(png_ptr, 0);
    }
-#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)
+#ifndef PNG_READ_OPT_PLTE_SUPPORTED
    else if (png_crc_error(png_ptr))  /* Only if we have a CRC error */
    {
       /* If we don't want to use the data from an ancillary chunk,
          we have two options: an error abort, or a warning and we
          ignore the data in this chunk (which should be OK, since
          it's considered ancillary for a RGB or RGBA image). */
       if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_USE))
       {
          if (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)
          {
             png_chunk_error(png_ptr, "CRC error");
          }
          else
          {
             png_chunk_warning(png_ptr, "CRC error");
             return;
          }
       }
       /* Otherwise, we (optionally) emit a warning and use the chunk. */
       else if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN))
       {
          png_chunk_warning(png_ptr, "CRC error");
       }
    }
 #endif
 
    png_set_PLTE(png_ptr, info_ptr, palette, num);
 
-#if defined(PNG_READ_tRNS_SUPPORTED)
+#ifdef PNG_READ_tRNS_SUPPORTED
    if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
    {
       if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
       {
          if (png_ptr->num_trans > (png_uint_16)num)
          {
             png_warning(png_ptr, "Truncating incorrect tRNS chunk length");
             png_ptr->num_trans = (png_uint_16)num;
          }
          if (info_ptr->num_trans > (png_uint_16)num)
@@ skipping 21 matching lines @@
 
    if (length != 0)
    {
       png_warning(png_ptr, "Incorrect IEND chunk length");
    }
    png_crc_finish(png_ptr, length);
 
    info_ptr = info_ptr; /* Quiet compiler warnings about unused info_ptr */
 }
 
-#if defined(PNG_READ_gAMA_SUPPORTED)
+#ifdef PNG_READ_gAMA_SUPPORTED
 void /* PRIVATE */
 png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_fixed_point igamma;
 #ifdef PNG_FLOATING_POINT_SUPPORTED
    float file_gamma;
 #endif
    png_byte buf[4];
 
    png_debug(1, "in png_handle_gAMA");
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before gAMA");
    else if (png_ptr->mode & PNG_HAVE_IDAT)
    {
       png_warning(png_ptr, "Invalid gAMA after IDAT");
       png_crc_finish(png_ptr, length);
       return;
    }
    else if (png_ptr->mode & PNG_HAVE_PLTE)
       /* Should be an error, but we can cope with it */
       png_warning(png_ptr, "Out of place gAMA chunk");
 
    if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
-#if defined(PNG_READ_sRGB_SUPPORTED)
+#ifdef PNG_READ_sRGB_SUPPORTED
       && !(info_ptr->valid & PNG_INFO_sRGB)
 #endif
       )
    {
       png_warning(png_ptr, "Duplicate gAMA chunk");
       png_crc_finish(png_ptr, length);
       return;
    }
 
    if (length != 4)
    {
       png_warning(png_ptr, "Incorrect gAMA chunk length");
       png_crc_finish(png_ptr, length);
       return;
    }
 
    png_crc_read(png_ptr, buf, 4);
    if (png_crc_finish(png_ptr, 0))
       return;
 
    igamma = (png_fixed_point)png_get_uint_32(buf);
    /* Check for zero gamma */
    if (igamma == 0)
       {
          png_warning(png_ptr,
            "Ignoring gAMA chunk with gamma=0");
          return;
       }
 
-#if defined(PNG_READ_sRGB_SUPPORTED)
+#ifdef PNG_READ_sRGB_SUPPORTED
    if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB))
       if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))
       {
          png_warning(png_ptr,
            "Ignoring incorrect gAMA value when sRGB is also present");
-#ifndef PNG_NO_CONSOLE_IO
+#ifdef PNG_CONSOLE_IO_SUPPORTED
          fprintf(stderr, "gamma = (%d/100000)", (int)igamma);
 #endif
          return;
       }
 #endif /* PNG_READ_sRGB_SUPPORTED */
 
 #ifdef PNG_FLOATING_POINT_SUPPORTED
    file_gamma = (float)igamma / (float)100000.0;
 #  ifdef PNG_READ_GAMMA_SUPPORTED
      png_ptr->gamma = file_gamma;
 #  endif
      png_set_gAMA(png_ptr, info_ptr, file_gamma);
 #endif
 #ifdef PNG_FIXED_POINT_SUPPORTED
    png_set_gAMA_fixed(png_ptr, info_ptr, igamma);
 #endif
 }
 #endif
 
-#if defined(PNG_READ_sBIT_SUPPORTED)
+#ifdef PNG_READ_sBIT_SUPPORTED
 void /* PRIVATE */
 png_handle_sBIT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_size_t truelen;
    png_byte buf[4];
 
    png_debug(1, "in png_handle_sBIT");
 
    buf[0] = buf[1] = buf[2] = buf[3] = 0;
 
@@ skipping 45 matching lines @@
       png_ptr->sig_bit.gray = buf[0];
       png_ptr->sig_bit.red = buf[0];
       png_ptr->sig_bit.green = buf[0];
       png_ptr->sig_bit.blue = buf[0];
       png_ptr->sig_bit.alpha = buf[1];
    }
    png_set_sBIT(png_ptr, info_ptr, &(png_ptr->sig_bit));
 }
 #endif
 
-#if defined(PNG_READ_cHRM_SUPPORTED)
+#ifdef PNG_READ_cHRM_SUPPORTED
 void /* PRIVATE */
 png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_byte buf[32];
 #ifdef PNG_FLOATING_POINT_SUPPORTED
    float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
 #endif
    png_fixed_point int_x_white, int_y_white, int_x_red, int_y_red, int_x_green,
       int_y_green, int_x_blue, int_y_blue;
 
    png_uint_32 uint_x, uint_y;
 
    png_debug(1, "in png_handle_cHRM");
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before cHRM");
    else if (png_ptr->mode & PNG_HAVE_IDAT)
    {
       png_warning(png_ptr, "Invalid cHRM after IDAT");
       png_crc_finish(png_ptr, length);
       return;
    }
    else if (png_ptr->mode & PNG_HAVE_PLTE)
       /* Should be an error, but we can cope with it */
       png_warning(png_ptr, "Missing PLTE before cHRM");
 
    if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM)
-#if defined(PNG_READ_sRGB_SUPPORTED)
+#ifdef PNG_READ_sRGB_SUPPORTED
       && !(info_ptr->valid & PNG_INFO_sRGB)
 #endif
       )
    {
       png_warning(png_ptr, "Duplicate cHRM chunk");
       png_crc_finish(png_ptr, length);
       return;
    }
 
    if (length != 32)
@@ skipping 31 matching lines @@
    white_x = (float)int_x_white / (float)100000.0;
    white_y = (float)int_y_white / (float)100000.0;
    red_x   = (float)int_x_red   / (float)100000.0;
    red_y   = (float)int_y_red   / (float)100000.0;
    green_x = (float)int_x_green / (float)100000.0;
    green_y = (float)int_y_green / (float)100000.0;
    blue_x  = (float)int_x_blue  / (float)100000.0;
    blue_y  = (float)int_y_blue  / (float)100000.0;
 #endif
 
-#if defined(PNG_READ_sRGB_SUPPORTED)
+#ifdef PNG_READ_sRGB_SUPPORTED
    if ((info_ptr != NULL) && (info_ptr->valid & PNG_INFO_sRGB))
       {
       if (PNG_OUT_OF_RANGE(int_x_white, 31270,  1000) ||
           PNG_OUT_OF_RANGE(int_y_white, 32900,  1000) ||
           PNG_OUT_OF_RANGE(int_x_red,   64000L, 1000) ||
           PNG_OUT_OF_RANGE(int_y_red,   33000,  1000) ||
           PNG_OUT_OF_RANGE(int_x_green, 30000,  1000) ||
           PNG_OUT_OF_RANGE(int_y_green, 60000L, 1000) ||
           PNG_OUT_OF_RANGE(int_x_blue,  15000,  1000) ||
           PNG_OUT_OF_RANGE(int_y_blue,   6000,  1000))
          {
             png_warning(png_ptr,
               "Ignoring incorrect cHRM value when sRGB is also present");
-#ifndef PNG_NO_CONSOLE_IO
+#ifdef PNG_CONSOLE_IO_SUPPORTED
 #ifdef PNG_FLOATING_POINT_SUPPORTED
             fprintf(stderr, "wx=%f, wy=%f, rx=%f, ry=%f\n",
                white_x, white_y, red_x, red_y);
             fprintf(stderr, "gx=%f, gy=%f, bx=%f, by=%f\n",
                green_x, green_y, blue_x, blue_y);
 #else
             fprintf(stderr, "wx=%ld, wy=%ld, rx=%ld, ry=%ld\n",
                int_x_white, int_y_white, int_x_red, int_y_red);
             fprintf(stderr, "gx=%ld, gy=%ld, bx=%ld, by=%ld\n",
                int_x_green, int_y_green, int_x_blue, int_y_blue);
 #endif
-#endif /* PNG_NO_CONSOLE_IO */
+#endif /* PNG_CONSOLE_IO_SUPPORTED */
          }
          return;
       }
 #endif /* PNG_READ_sRGB_SUPPORTED */
 
 #ifdef PNG_FLOATING_POINT_SUPPORTED
    png_set_cHRM(png_ptr, info_ptr,
       white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
 #endif
 #ifdef PNG_FIXED_POINT_SUPPORTED
    png_set_cHRM_fixed(png_ptr, info_ptr,
       int_x_white, int_y_white, int_x_red, int_y_red, int_x_green,
       int_y_green, int_x_blue, int_y_blue);
 #endif
 }
 #endif
 
-#if defined(PNG_READ_sRGB_SUPPORTED)
+#ifdef PNG_READ_sRGB_SUPPORTED
 void /* PRIVATE */
 png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    int intent;
    png_byte buf[1];
 
    png_debug(1, "in png_handle_sRGB");
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before sRGB");
@@ skipping 41 matching lines @@
       igamma=info_ptr->int_gamma;
 #else
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
       igamma=(png_fixed_point)(info_ptr->gamma * 100000.);
 #  endif
 #endif
       if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))
       {
          png_warning(png_ptr,
            "Ignoring incorrect gAMA value when sRGB is also present");
-#ifndef PNG_NO_CONSOLE_IO
+#ifdef PNG_CONSOLE_IO_SUPPORTED
 #  ifdef PNG_FIXED_POINT_SUPPORTED
          fprintf(stderr, "incorrect gamma=(%d/100000)\n",
             (int)png_ptr->int_gamma);
 #  else
 #    ifdef PNG_FLOATING_POINT_SUPPORTED
          fprintf(stderr, "incorrect gamma=%f\n", png_ptr->gamma);
 #    endif
 #  endif
 #endif
       }
@@ skipping 15 matching lines @@
             png_warning(png_ptr,
               "Ignoring incorrect cHRM value when sRGB is also present");
          }
 #endif /* PNG_FIXED_POINT_SUPPORTED */
 #endif /* PNG_READ_cHRM_SUPPORTED */
 
    png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr, intent);
 }
 #endif /* PNG_READ_sRGB_SUPPORTED */
 
-#if defined(PNG_READ_iCCP_SUPPORTED)
+#ifdef PNG_READ_iCCP_SUPPORTED
 void /* PRIVATE */
 png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 /* Note: this does not properly handle chunks that are > 64K under DOS */
 {
    png_byte compression_type;
    png_bytep pC;
    png_charp profile;
    png_uint_32 skip = 0;
    png_uint_32 profile_size, profile_length;
    png_size_t slength, prefix_length, data_length;
@@ skipping 99 matching lines @@
       return;
    }
 
    png_set_iCCP(png_ptr, info_ptr, png_ptr->chunkdata,
      compression_type, png_ptr->chunkdata + prefix_length, profile_length);
    png_free(png_ptr, png_ptr->chunkdata);
    png_ptr->chunkdata = NULL;
 }
 #endif /* PNG_READ_iCCP_SUPPORTED */
 
-#if defined(PNG_READ_sPLT_SUPPORTED)
+#ifdef PNG_READ_sPLT_SUPPORTED
 void /* PRIVATE */
 png_handle_sPLT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 /* Note: this does not properly handle chunks that are > 64K under DOS */
 {
    png_bytep entry_start;
    png_sPLT_t new_palette;
-#ifdef PNG_NO_POINTER_INDEXING
+#ifdef PNG_POINTER_INDEXING_SUPPORTED
    png_sPLT_entryp pp;
 #endif
    int data_length, entry_size, i;
    png_uint_32 skip = 0;
    png_size_t slength;
 
    png_debug(1, "in png_handle_sPLT");
 
+#ifdef PNG_USER_LIMITS_SUPPORTED
+
+   if (png_ptr->user_chunk_cache_max != 0)
+   {
+      if (png_ptr->user_chunk_cache_max == 1)
+      {
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+      if (--png_ptr->user_chunk_cache_max == 1)
+      {
+         png_warning(png_ptr, "No space in chunk cache for sPLT");
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+   }
+#endif
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before sPLT");
    else if (png_ptr->mode & PNG_HAVE_IDAT)
    {
       png_warning(png_ptr, "Invalid sPLT after IDAT");
       png_crc_finish(png_ptr, length);
       return;
    }
 
@@ skipping 13 matching lines @@
 
    if (png_crc_finish(png_ptr, skip))
    {
       png_free(png_ptr, png_ptr->chunkdata);
       png_ptr->chunkdata = NULL;
       return;
    }
 
    png_ptr->chunkdata[slength] = 0x00;
 
-   for (entry_start = (png_bytep)png_ptr->chunkdata; *entry_start; entry_start++)
+   for (entry_start = (png_bytep)png_ptr->chunkdata; *entry_start;
+       entry_start++)
       /* Empty loop to find end of name */ ;
    ++entry_start;
 
    /* A sample depth should follow the separator, and we should be on it  */
    if (entry_start > (png_bytep)png_ptr->chunkdata + slength - 2)
    {
       png_free(png_ptr, png_ptr->chunkdata);
       png_ptr->chunkdata = NULL;
       png_warning(png_ptr, "malformed sPLT chunk");
       return;
@@ skipping 20 matching lines @@
        return;
    }
    new_palette.entries = (png_sPLT_entryp)png_malloc_warn(
        png_ptr, new_palette.nentries * png_sizeof(png_sPLT_entry));
    if (new_palette.entries == NULL)
    {
        png_warning(png_ptr, "sPLT chunk requires too much memory");
        return;
    }
 
-#ifndef PNG_NO_POINTER_INDEXING
+#ifdef PNG_POINTER_INDEXING_SUPPORTED
    for (i = 0; i < new_palette.nentries; i++)
    {
-      png_sPLT_entryp pp = new_palette.entries + i;
+      pp = new_palette.entries + i;
 
       if (new_palette.depth == 8)
       {
           pp->red = *entry_start++;
           pp->green = *entry_start++;
           pp->blue = *entry_start++;
           pp->alpha = *entry_start++;
       }
       else
       {
@@ skipping 31 matching lines @@
    new_palette.name = png_ptr->chunkdata;
 
    png_set_sPLT(png_ptr, info_ptr, &new_palette, 1);
 
    png_free(png_ptr, png_ptr->chunkdata);
    png_ptr->chunkdata = NULL;
    png_free(png_ptr, new_palette.entries);
 }
 #endif /* PNG_READ_sPLT_SUPPORTED */
 
-#if defined(PNG_READ_tRNS_SUPPORTED)
+#ifdef PNG_READ_tRNS_SUPPORTED
 void /* PRIVATE */
 png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_byte readbuf[PNG_MAX_PALETTE_LENGTH];
 
    png_debug(1, "in png_handle_tRNS");
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before tRNS");
    else if (png_ptr->mode & PNG_HAVE_IDAT)
@@ skipping 74 matching lines @@
    {
       png_ptr->num_trans = 0;
       return;
    }
 
    png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans,
       &(png_ptr->trans_values));
 }
 #endif
 
-#if defined(PNG_READ_bKGD_SUPPORTED)
+#ifdef PNG_READ_bKGD_SUPPORTED
 void /* PRIVATE */
 png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_size_t truelen;
    png_byte buf[6];
 
    png_debug(1, "in png_handle_bKGD");
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before bKGD");
@@ skipping 68 matching lines @@
    {
       png_ptr->background.red = png_get_uint_16(buf);
       png_ptr->background.green = png_get_uint_16(buf + 2);
       png_ptr->background.blue = png_get_uint_16(buf + 4);
    }
 
    png_set_bKGD(png_ptr, info_ptr, &(png_ptr->background));
 }
 #endif
 
-#if defined(PNG_READ_hIST_SUPPORTED)
+#ifdef PNG_READ_hIST_SUPPORTED
 void /* PRIVATE */
 png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    unsigned int num, i;
    png_uint_16 readbuf[PNG_MAX_PALETTE_LENGTH];
 
    png_debug(1, "in png_handle_hIST");
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before hIST");
@@ skipping 33 matching lines @@
       readbuf[i] = png_get_uint_16(buf);
    }
 
    if (png_crc_finish(png_ptr, 0))
       return;
 
    png_set_hIST(png_ptr, info_ptr, readbuf);
 }
 #endif
 
-#if defined(PNG_READ_pHYs_SUPPORTED)
+#ifdef PNG_READ_pHYs_SUPPORTED
 void /* PRIVATE */
 png_handle_pHYs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_byte buf[9];
    png_uint_32 res_x, res_y;
    int unit_type;
 
    png_debug(1, "in png_handle_pHYs");
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
@@ skipping 22 matching lines @@
    if (png_crc_finish(png_ptr, 0))
       return;
 
    res_x = png_get_uint_32(buf);
    res_y = png_get_uint_32(buf + 4);
    unit_type = buf[8];
    png_set_pHYs(png_ptr, info_ptr, res_x, res_y, unit_type);
 }
 #endif
 
-#if defined(PNG_READ_oFFs_SUPPORTED)
+#ifdef PNG_READ_oFFs_SUPPORTED
 void /* PRIVATE */
 png_handle_oFFs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_byte buf[9];
    png_int_32 offset_x, offset_y;
    int unit_type;
 
    png_debug(1, "in png_handle_oFFs");
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
@@ skipping 22 matching lines @@
    if (png_crc_finish(png_ptr, 0))
       return;
 
    offset_x = png_get_int_32(buf);
    offset_y = png_get_int_32(buf + 4);
    unit_type = buf[8];
    png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y, unit_type);
 }
 #endif
 
-#if defined(PNG_READ_pCAL_SUPPORTED)
+#ifdef PNG_READ_pCAL_SUPPORTED
 /* Read the pCAL chunk (described in the PNG Extensions document) */
 void /* PRIVATE */
 png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_int_32 X0, X1;
    png_byte type, nparams;
    png_charp buf, units, endptr;
    png_charpp params;
    png_size_t slength;
    int i;
@@ skipping 113 matching lines @@
 
    png_set_pCAL(png_ptr, info_ptr, png_ptr->chunkdata, X0, X1, type, nparams,
       units, params);
 
    png_free(png_ptr, png_ptr->chunkdata);
    png_ptr->chunkdata = NULL;
    png_free(png_ptr, params);
 }
 #endif
 
-#if defined(PNG_READ_sCAL_SUPPORTED)
+#ifdef PNG_READ_sCAL_SUPPORTED
 /* Read the sCAL chunk */
 void /* PRIVATE */
 png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_charp ep;
 #ifdef PNG_FLOATING_POINT_SUPPORTED
    double width, height;
    png_charp vp;
 #else
 #ifdef PNG_FIXED_POINT_SUPPORTED
@@ skipping 122 matching lines @@
 
    png_free(png_ptr, png_ptr->chunkdata);
    png_ptr->chunkdata = NULL;
 #if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
    png_free(png_ptr, swidth);
    png_free(png_ptr, sheight);
 #endif
 }
 #endif
 
-#if defined(PNG_READ_tIME_SUPPORTED)
+#ifdef PNG_READ_tIME_SUPPORTED
 void /* PRIVATE */
 png_handle_tIME(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_byte buf[7];
    png_time mod_time;
 
    png_debug(1, "in png_handle_tIME");
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Out of place tIME chunk");
@@ skipping 22 matching lines @@
    mod_time.minute = buf[5];
    mod_time.hour = buf[4];
    mod_time.day = buf[3];
    mod_time.month = buf[2];
    mod_time.year = png_get_uint_16(buf);
 
    png_set_tIME(png_ptr, info_ptr, &mod_time);
 }
 #endif
 
-#if defined(PNG_READ_tEXt_SUPPORTED)
+#ifdef PNG_READ_tEXt_SUPPORTED
 /* Note: this does not properly handle chunks that are > 64K under DOS */
 void /* PRIVATE */
 png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_textp text_ptr;
    png_charp key;
    png_charp text;
    png_uint_32 skip = 0;
    png_size_t slength;
    int ret;
 
    png_debug(1, "in png_handle_tEXt");
 
+#ifdef PNG_USER_LIMITS_SUPPORTED
+   if (png_ptr->user_chunk_cache_max != 0)
+   {
+      if (png_ptr->user_chunk_cache_max == 1)
+      {
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+      if (--png_ptr->user_chunk_cache_max == 1)
+      {
+         png_warning(png_ptr, "No space in chunk cache for tEXt");
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+   }
+#endif
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before tEXt");
 
    if (png_ptr->mode & PNG_HAVE_IDAT)
       png_ptr->mode |= PNG_AFTER_IDAT;
 
 #ifdef PNG_MAX_MALLOC_64K
    if (length > (png_uint_32)65535L)
    {
@@ skipping 53 matching lines @@
    ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
 
    png_free(png_ptr, png_ptr->chunkdata);
    png_ptr->chunkdata = NULL;
    png_free(png_ptr, text_ptr);
    if (ret)
      png_warning(png_ptr, "Insufficient memory to process text chunk.");
 }
 #endif
 
-#if defined(PNG_READ_zTXt_SUPPORTED)
+#ifdef PNG_READ_zTXt_SUPPORTED
 /* Note: this does not correctly handle chunks that are > 64K under DOS */
 void /* PRIVATE */
 png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_textp text_ptr;
    png_charp text;
    int comp_type;
    int ret;
    png_size_t slength, prefix_len, data_len;
 
    png_debug(1, "in png_handle_zTXt");
 
+#ifdef PNG_USER_LIMITS_SUPPORTED
+   if (png_ptr->user_chunk_cache_max != 0)
+   {
+      if (png_ptr->user_chunk_cache_max == 1)
+      {
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+      if (--png_ptr->user_chunk_cache_max == 1)
+      {
+         png_warning(png_ptr, "No space in chunk cache for zTXt");
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+   }
+#endif
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before zTXt");
 
    if (png_ptr->mode & PNG_HAVE_IDAT)
       png_ptr->mode |= PNG_AFTER_IDAT;
 
 #ifdef PNG_MAX_MALLOC_64K
    /* We will no doubt have problems with chunks even half this size, but
       there is no hard and fast rule to tell us where to stop. */
@@ skipping 71 matching lines @@
    ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
 
    png_free(png_ptr, text_ptr);
    png_free(png_ptr, png_ptr->chunkdata);
    png_ptr->chunkdata = NULL;
    if (ret)
      png_error(png_ptr, "Insufficient memory to store zTXt chunk.");
 }
 #endif
 
-#if defined(PNG_READ_iTXt_SUPPORTED)
+#ifdef PNG_READ_iTXt_SUPPORTED
 /* Note: this does not correctly handle chunks that are > 64K under DOS */
 void /* PRIVATE */
 png_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_textp text_ptr;
    png_charp key, lang, text, lang_key;
    int comp_flag;
    int comp_type = 0;
    int ret;
    png_size_t slength, prefix_len, data_len;
 
    png_debug(1, "in png_handle_iTXt");
 
+#ifdef PNG_USER_LIMITS_SUPPORTED
+   if (png_ptr->user_chunk_cache_max != 0)
+   {
+      if (png_ptr->user_chunk_cache_max == 1)
+      {
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+      if (--png_ptr->user_chunk_cache_max == 1)
+      {
+         png_warning(png_ptr, "No space in chunk cache for iTXt");
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+   }
+#endif
 
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before iTXt");
 
    if (png_ptr->mode & PNG_HAVE_IDAT)
       png_ptr->mode |= PNG_AFTER_IDAT;
 
 #ifdef PNG_MAX_MALLOC_64K
    /* We will no doubt have problems with chunks even half this size, but
       there is no hard and fast rule to tell us where to stop. */
@@ skipping 108 matching lines @@
    chunk name, CRC, or a critical chunk), the chunk is silently ignored
    -- unless the PNG_FLAG_UNKNOWN_CHUNKS_SUPPORTED flag is on in which
    case it will be saved away to be written out later. */
 void /* PRIVATE */
 png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 {
    png_uint_32 skip = 0;
 
    png_debug(1, "in png_handle_unknown");
 
+#ifdef PNG_USER_LIMITS_SUPPORTED
+   if (png_ptr->user_chunk_cache_max != 0)
+   {
+      if (png_ptr->user_chunk_cache_max == 1)
+      {
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+      if (--png_ptr->user_chunk_cache_max == 1)
+      {
+         png_warning(png_ptr, "No space in chunk cache for unknown chunk");
+         png_crc_finish(png_ptr, length);
+         return;
+      }
+   }
+#endif
 
    if (png_ptr->mode & PNG_HAVE_IDAT)
    {
 #ifdef PNG_USE_LOCAL_ARRAYS
       PNG_CONST PNG_IDAT;
 #endif
       if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))  /* Not an IDAT */
          png_ptr->mode |= PNG_AFTER_IDAT;
    }
 
    if (!(png_ptr->chunk_name[0] & 0x20))
    {
-#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
       if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
            PNG_HANDLE_CHUNK_ALWAYS
-#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
            && png_ptr->read_user_chunk_fn == NULL
 #endif
         )
 #endif
           png_chunk_error(png_ptr, "unknown critical chunk");
    }
 
-#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
-   if ((png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS) ||
-       (png_ptr->read_user_chunk_fn != NULL))
+#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
+   if ((png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
+#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
+       || (png_ptr->read_user_chunk_fn != NULL)
+#endif
+        )
    {
 #ifdef PNG_MAX_MALLOC_64K
        if (length > (png_uint_32)65535L)
        {
            png_warning(png_ptr, "unknown chunk too large to fit in memory");
            skip = length - (png_uint_32)65535L;
            length = (png_uint_32)65535L;
        }
 #endif
        png_memcpy((png_charp)png_ptr->unknown_chunk.name,
-                  (png_charp)png_ptr->chunk_name, 
+                  (png_charp)png_ptr->chunk_name,
                   png_sizeof(png_ptr->unknown_chunk.name));
-       png_ptr->unknown_chunk.name[png_sizeof(png_ptr->unknown_chunk.name)-1] = '\0';
+       png_ptr->unknown_chunk.name[png_sizeof(png_ptr->unknown_chunk.name)-1]
+           = '\0';
        png_ptr->unknown_chunk.size = (png_size_t)length;
        if (length == 0)
          png_ptr->unknown_chunk.data = NULL;
        else
        {
          png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length);
          png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length);
        }
-#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
        if (png_ptr->read_user_chunk_fn != NULL)
        {
           /* Callback to user unknown chunk handler */
           int ret;
           ret = (*(png_ptr->read_user_chunk_fn))
             (png_ptr, &png_ptr->unknown_chunk);
           if (ret < 0)
              png_chunk_error(png_ptr, "error in user chunk");
           if (ret == 0)
           {
              if (!(png_ptr->chunk_name[0] & 0x20))
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
                 if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
                      PNG_HANDLE_CHUNK_ALWAYS)
+#endif
                    png_chunk_error(png_ptr, "unknown critical chunk");
              png_set_unknown_chunks(png_ptr, info_ptr,
                &png_ptr->unknown_chunk, 1);
           }
        }
        else
 #endif
        png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
        png_free(png_ptr, png_ptr->unknown_chunk.data);
        png_ptr->unknown_chunk.data = NULL;
    }
    else
 #endif
       skip = length;
 
    png_crc_finish(png_ptr, skip);
 
-#if !defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+#ifndef PNG_READ_USER_CHUNKS_SUPPORTED
    info_ptr = info_ptr; /* Quiet compiler warnings about unused info_ptr */
 #endif
 }
 
 /* This function is called to verify that a chunk name is valid.
    This function can't have the "critical chunk check" incorporated
    into it, since in the future we will need to be able to call user
    functions to handle unknown critical chunks after we check that
    the chunk name itself is valid. */
 
@@ skipping 37 matching lines @@
          case 1:
          {
             png_bytep sp = png_ptr->row_buf + 1;
             png_bytep dp = row;
             int s_inc, s_start, s_end;
             int m = 0x80;
             int shift;
             png_uint_32 i;
             png_uint_32 row_width = png_ptr->width;
 
-#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+#ifdef PNG_READ_PACKSWAP_SUPPORTED
             if (png_ptr->transformations & PNG_PACKSWAP)
             {
                 s_start = 0;
                 s_end = 7;
                 s_inc = 1;
             }
             else
 #endif
             {
                 s_start = 7;
@@ skipping 34 matching lines @@
          {
             png_bytep sp = png_ptr->row_buf + 1;
             png_bytep dp = row;
             int s_start, s_end, s_inc;
             int m = 0x80;
             int shift;
             png_uint_32 i;
             png_uint_32 row_width = png_ptr->width;
             int value;
 
-#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+#ifdef PNG_READ_PACKSWAP_SUPPORTED
             if (png_ptr->transformations & PNG_PACKSWAP)
             {
                s_start = 0;
                s_end = 6;
                s_inc = 2;
             }
             else
 #endif
             {
                s_start = 6;
@@ skipping 31 matching lines @@
          {
             png_bytep sp = png_ptr->row_buf + 1;
             png_bytep dp = row;
             int s_start, s_end, s_inc;
             int m = 0x80;
             int shift;
             png_uint_32 i;
             png_uint_32 row_width = png_ptr->width;
             int value;
 
-#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+#ifdef PNG_READ_PACKSWAP_SUPPORTED
             if (png_ptr->transformations & PNG_PACKSWAP)
             {
                s_start = 0;
                s_end = 4;
                s_inc = 4;
             }
             else
 #endif
             {
                s_start = 4;
@@ skipping 62 matching lines @@
 void png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
    png_uint_32 transformations)
  */
 void /* PRIVATE */
 png_do_read_interlace(png_structp png_ptr)
 {
    png_row_infop row_info = &(png_ptr->row_info);
    png_bytep row = png_ptr->row_buf + 1;
    int pass = png_ptr->pass;
    png_uint_32 transformations = png_ptr->transformations;
-#ifdef PNG_USE_LOCAL_ARRAYS
    /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
    /* Offset to next interlace block */
    PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
-#endif
 
    png_debug(1, "in png_do_read_interlace");
    if (row != NULL && row_info != NULL)
    {
       png_uint_32 final_width;
 
       final_width = row_info->width * png_pass_inc[pass];
 
       switch (row_info->pixel_depth)
       {
          case 1:
          {
             png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3);
             png_bytep dp = row + (png_size_t)((final_width - 1) >> 3);
             int sshift, dshift;
             int s_start, s_end, s_inc;
             int jstop = png_pass_inc[pass];
             png_byte v;
             png_uint_32 i;
             int j;
 
-#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+#ifdef PNG_READ_PACKSWAP_SUPPORTED
             if (transformations & PNG_PACKSWAP)
             {
                 sshift = (int)((row_info->width + 7) & 0x07);
                 dshift = (int)((final_width + 7) & 0x07);
                 s_start = 7;
                 s_end = 0;
                 s_inc = -1;
             }
             else
 #endif
@@ skipping 32 matching lines @@
          }
          case 2:
          {
             png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2);
             png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2);
             int sshift, dshift;
             int s_start, s_end, s_inc;
             int jstop = png_pass_inc[pass];
             png_uint_32 i;
 
-#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+#ifdef PNG_READ_PACKSWAP_SUPPORTED
             if (transformations & PNG_PACKSWAP)
             {
                sshift = (int)(((row_info->width + 3) & 0x03) << 1);
                dshift = (int)(((final_width + 3) & 0x03) << 1);
                s_start = 6;
                s_end = 0;
                s_inc = -2;
             }
             else
 #endif
@@ skipping 35 matching lines @@
          }
          case 4:
          {
             png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1);
             png_bytep dp = row + (png_size_t)((final_width - 1) >> 1);
             int sshift, dshift;
             int s_start, s_end, s_inc;
             png_uint_32 i;
             int jstop = png_pass_inc[pass];
 
-#if defined(PNG_READ_PACKSWAP_SUPPORTED)
+#ifdef PNG_READ_PACKSWAP_SUPPORTED
             if (transformations & PNG_PACKSWAP)
             {
                sshift = (int)(((row_info->width + 1) & 0x01) << 2);
                dshift = (int)(((final_width + 1) & 0x01) << 2);
                s_start = 4;
                s_end = 0;
                s_inc = -4;
             }
             else
 #endif
@@ skipping 28 matching lines @@
                   sp--;
                }
                else
                   sshift += s_inc;
             }
             break;
          }
          default:
          {
             png_size_t pixel_bytes = (row_info->pixel_depth >> 3);
-            png_bytep sp = row + (png_size_t)(row_info->width - 1) * pixel_bytes;
+            png_bytep sp = row + (png_size_t)(row_info->width - 1)
+                * pixel_bytes;
             png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes;
 
             int jstop = png_pass_inc[pass];
             png_uint_32 i;
 
             for (i = 0; i < row_info->width; i++)
             {
                png_byte v[8];
                int j;
 
                png_memcpy(v, sp, pixel_bytes);
                for (j = 0; j < jstop; j++)
                {
                   png_memcpy(dp, v, pixel_bytes);
                   dp -= pixel_bytes;
                }
                sp -= pixel_bytes;
             }
             break;
          }
       }
       row_info->width = final_width;
       row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, final_width);
    }
-#if !defined(PNG_READ_PACKSWAP_SUPPORTED)
+#ifndef PNG_READ_PACKSWAP_SUPPORTED
    transformations = transformations; /* Silence compiler warning */
 #endif
 }
 #endif /* PNG_READ_INTERLACING_SUPPORTED */
 
 void /* PRIVATE */
 png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
    png_bytep prev_row, int filter)
 {
    png_debug(1, "in png_read_filter_row");
@@ skipping 108 matching lines @@
          }
          break;
       }
       default:
          png_warning(png_ptr, "Ignoring bad adaptive filter type");
          *row = 0;
          break;
    }
 }
 
-#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
 void /* PRIVATE */
 png_read_finish_row(png_structp png_ptr)
 {
-#ifdef PNG_USE_LOCAL_ARRAYS
 #ifdef PNG_READ_INTERLACING_SUPPORTED
    /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
 
    /* Start of interlace block */
    PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
 
    /* Offset to next interlace block */
    PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
 
    /* Start of interlace block in the y direction */
    PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
 
    /* Offset to next interlace block in the y direction */
    PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
 #endif /* PNG_READ_INTERLACING_SUPPORTED */
-#endif
 
    png_debug(1, "in png_read_finish_row");
    png_ptr->row_number++;
    if (png_ptr->row_number < png_ptr->num_rows)
       return;
 
 #ifdef PNG_READ_INTERLACING_SUPPORTED
    if (png_ptr->interlaced)
    {
       png_ptr->row_number = 0;
       png_memset_check(png_ptr, png_ptr->prev_row, 0,
          png_ptr->rowbytes + 1);
       do
       {
          png_ptr->pass++;
          if (png_ptr->pass >= 7)
             break;
          png_ptr->iwidth = (png_ptr->width +
             png_pass_inc[png_ptr->pass] - 1 -
             png_pass_start[png_ptr->pass]) /
             png_pass_inc[png_ptr->pass];
 
-         png_ptr->irowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,
-            png_ptr->iwidth) + 1;
-
          if (!(png_ptr->transformations & PNG_INTERLACE))
          {
             png_ptr->num_rows = (png_ptr->height +
                png_pass_yinc[png_ptr->pass] - 1 -
                png_pass_ystart[png_ptr->pass]) /
                png_pass_yinc[png_ptr->pass];
             if (!(png_ptr->num_rows))
                continue;
          }
          else  /* if (png_ptr->transformations & PNG_INTERLACE) */
@@ skipping 38 matching lines @@
             if (png_ptr->zbuf_size > png_ptr->idat_size)
                png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
             png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zstream.avail_in);
             png_ptr->idat_size -= png_ptr->zstream.avail_in;
          }
          ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
          if (ret == Z_STREAM_END)
          {
             if (!(png_ptr->zstream.avail_out) || png_ptr->zstream.avail_in ||
                png_ptr->idat_size)
-               png_warning(png_ptr, "Extra compressed data");
+               png_warning(png_ptr, "Extra compressed data.");
             png_ptr->mode |= PNG_AFTER_IDAT;
             png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
             break;
          }
          if (ret != Z_OK)
             png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
                       "Decompression Error");
 
          if (!(png_ptr->zstream.avail_out))
          {
             png_warning(png_ptr, "Extra compressed data.");
             png_ptr->mode |= PNG_AFTER_IDAT;
             png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
             break;
          }
 
       }
       png_ptr->zstream.avail_out = 0;
    }
 
    if (png_ptr->idat_size || png_ptr->zstream.avail_in)
-      png_warning(png_ptr, "Extra compression data");
+      png_warning(png_ptr, "Extra compression data.");
 
    inflateReset(&png_ptr->zstream);
 
    png_ptr->mode |= PNG_AFTER_IDAT;
 }
-#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
 
 void /* PRIVATE */
 png_read_start_row(png_structp png_ptr)
 {
-#ifdef PNG_USE_LOCAL_ARRAYS
 #ifdef PNG_READ_INTERLACING_SUPPORTED
    /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
 
    /* Start of interlace block */
    PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
 
    /* Offset to next interlace block */
    PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
 
    /* Start of interlace block in the y direction */
    PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
 
    /* Offset to next interlace block in the y direction */
    PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
 #endif
-#endif
 
    int max_pixel_depth;
    png_size_t row_bytes;
 
    png_debug(1, "in png_read_start_row");
    png_ptr->zstream.avail_in = 0;
    png_init_read_transformations(png_ptr);
 #ifdef PNG_READ_INTERLACING_SUPPORTED
    if (png_ptr->interlaced)
    {
       if (!(png_ptr->transformations & PNG_INTERLACE))
          png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
             png_pass_ystart[0]) / png_pass_yinc[0];
       else
          png_ptr->num_rows = png_ptr->height;
 
       png_ptr->iwidth = (png_ptr->width +
          png_pass_inc[png_ptr->pass] - 1 -
          png_pass_start[png_ptr->pass]) /
          png_pass_inc[png_ptr->pass];
-
-         png_ptr->irowbytes =
-            PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1;
    }
    else
 #endif /* PNG_READ_INTERLACING_SUPPORTED */
    {
       png_ptr->num_rows = png_ptr->height;
       png_ptr->iwidth = png_ptr->width;
-      png_ptr->irowbytes = png_ptr->rowbytes + 1;
    }
    max_pixel_depth = png_ptr->pixel_depth;
 
-#if defined(PNG_READ_PACK_SUPPORTED)
+#ifdef PNG_READ_PACK_SUPPORTED
    if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8)
       max_pixel_depth = 8;
 #endif
 
-#if defined(PNG_READ_EXPAND_SUPPORTED)
+#ifdef PNG_READ_EXPAND_SUPPORTED
    if (png_ptr->transformations & PNG_EXPAND)
    {
       if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
       {
          if (png_ptr->num_trans)
             max_pixel_depth = 32;
          else
             max_pixel_depth = 24;
       }
       else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
       {
          if (max_pixel_depth < 8)
             max_pixel_depth = 8;
          if (png_ptr->num_trans)
             max_pixel_depth *= 2;
       }
       else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
       {
          if (png_ptr->num_trans)
          {
             max_pixel_depth *= 4;
             max_pixel_depth /= 3;
          }
       }
    }
 #endif
 
-#if defined(PNG_READ_FILLER_SUPPORTED)
+#ifdef PNG_READ_FILLER_SUPPORTED
    if (png_ptr->transformations & (PNG_FILLER))
    {
       if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
          max_pixel_depth = 32;
       else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
       {
          if (max_pixel_depth <= 8)
             max_pixel_depth = 16;
          else
             max_pixel_depth = 32;
       }
       else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
       {
          if (max_pixel_depth <= 32)
             max_pixel_depth = 32;
          else
             max_pixel_depth = 64;
       }
    }
 #endif
 
-#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
+#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
    if (png_ptr->transformations & PNG_GRAY_TO_RGB)
    {
       if (
-#if defined(PNG_READ_EXPAND_SUPPORTED)
+#ifdef PNG_READ_EXPAND_SUPPORTED
         (png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) ||
 #endif
-#if defined(PNG_READ_FILLER_SUPPORTED)
+#ifdef PNG_READ_FILLER_SUPPORTED
         (png_ptr->transformations & (PNG_FILLER)) ||
 #endif
         png_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
       {
          if (max_pixel_depth <= 16)
             max_pixel_depth = 32;
          else
             max_pixel_depth = 64;
       }
       else
@@ skipping 34 matching lines @@
    row_bytes = PNG_ROWBYTES(max_pixel_depth, row_bytes) +
       1 + ((max_pixel_depth + 7) >> 3);
 #ifdef PNG_MAX_MALLOC_64K
    if (row_bytes > (png_uint_32)65536L)
       png_error(png_ptr, "This image requires a row greater than 64KB");
 #endif
 
    if (row_bytes + 64 > png_ptr->old_big_row_buf_size)
    {
      png_free(png_ptr, png_ptr->big_row_buf);
-     png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes + 64);
      if (png_ptr->interlaced)
-       png_memset(png_ptr->big_row_buf, 0, row_bytes + 64);
+        png_ptr->big_row_buf = (png_bytep)png_calloc(png_ptr,
+            row_bytes + 64);
+     else
+        png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr,
+            row_bytes + 64);
+     png_ptr->old_big_row_buf_size = row_bytes + 64;
+
+     /* Use 32 bytes of padding before and after row_buf. */
      png_ptr->row_buf = png_ptr->big_row_buf + 32;
      png_ptr->old_big_row_buf_size = row_bytes + 64;
    }
 
 #ifdef PNG_MAX_MALLOC_64K
    if ((png_uint_32)row_bytes + 1 > (png_uint_32)65536L)
       png_error(png_ptr, "This image requires a row greater than 64KB");
 #endif
    if ((png_uint_32)row_bytes > (png_uint_32)(PNG_SIZE_MAX - 1))
       png_error(png_ptr, "Row has too many bytes to allocate in memory.");
 
    if (row_bytes + 1 > png_ptr->old_prev_row_size)
    {
       png_free(png_ptr, png_ptr->prev_row);
       png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)(
         row_bytes + 1));
       png_memset_check(png_ptr, png_ptr->prev_row, 0, row_bytes + 1);
       png_ptr->old_prev_row_size = row_bytes + 1;
    }
 
    png_ptr->rowbytes = row_bytes;
 
    png_debug1(3, "width = %lu,", png_ptr->width);
    png_debug1(3, "height = %lu,", png_ptr->height);
    png_debug1(3, "iwidth = %lu,", png_ptr->iwidth);
    png_debug1(3, "num_rows = %lu,", png_ptr->num_rows);
    png_debug1(3, "rowbytes = %lu,", png_ptr->rowbytes);
-   png_debug1(3, "irowbytes = %lu", png_ptr->irowbytes);
+   png_debug1(3, "irowbytes = %lu",
+       PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1);
 
    png_ptr->flags |= PNG_FLAG_ROW_INIT;
 }
 #endif /* PNG_READ_SUPPORTED */