cleaning up common OSX code

[wxWidgets.git] / src / png / pngwutil.c

diff --git a/src/png/pngwutil.c b/src/png/pngwutil.c
index 22155e93f9c29518a1df4d3711365ad9413ebf90..c79b1fec6f94bb302763943d474026fa6988e807 100644 (file)
--- a/src/png/pngwutil.c
+++ b/src/png/pngwutil.c
@@ -1,9 +1,9 @@
 
 /* pngwutil.c - utilities to write a PNG file
  *
 
 /* pngwutil.c - utilities to write a PNG file
  *

- * libpng 1.2.4 - July 8, 2002
+ * Last changed in libpng 1.2.19 August 19, 2007

  * For conditions of distribution and use, see copyright notice in png.h
  * For conditions of distribution and use, see copyright notice in png.h

- * Copyright (c) 1998-2002 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2007 Glenn Randers-Pehrson

  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  */
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  */


@@ -16,7 +16,7 @@
  * with unsigned numbers for convenience, although one supported
  * ancillary chunk uses signed (two's complement) numbers.
  */
  * with unsigned numbers for convenience, although one supported
  * ancillary chunk uses signed (two's complement) numbers.
  */

-void /* PRIVATE */
+void PNGAPI

 png_save_uint_32(png_bytep buf, png_uint_32 i)
 {
    buf[0] = (png_byte)((i >> 24) & 0xff);
 png_save_uint_32(png_bytep buf, png_uint_32 i)
 {
    buf[0] = (png_byte)((i >> 24) & 0xff);


@@ -25,12 +25,11 @@ png_save_uint_32(png_bytep buf, png_uint_32 i)
    buf[3] = (png_byte)(i & 0xff);
 }
 
    buf[3] = (png_byte)(i & 0xff);
 }
 

-#if defined(PNG_WRITE_pCAL_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)

 /* The png_save_int_32 function assumes integers are stored in two's
  * complement format.  If this isn't the case, then this routine needs to
  * be modified to write data in two's complement format.
  */
 /* The png_save_int_32 function assumes integers are stored in two's
  * complement format.  If this isn't the case, then this routine needs to
  * be modified to write data in two's complement format.
  */

-void /* PRIVATE */
+void PNGAPI

 png_save_int_32(png_bytep buf, png_int_32 i)
 {
    buf[0] = (png_byte)((i >> 24) & 0xff);
 png_save_int_32(png_bytep buf, png_int_32 i)
 {
    buf[0] = (png_byte)((i >> 24) & 0xff);


@@ -38,13 +37,12 @@ png_save_int_32(png_bytep buf, png_int_32 i)
    buf[2] = (png_byte)((i >> 8) & 0xff);
    buf[3] = (png_byte)(i & 0xff);
 }
    buf[2] = (png_byte)((i >> 8) & 0xff);
    buf[3] = (png_byte)(i & 0xff);
 }

-#endif

 
 /* Place a 16-bit number into a buffer in PNG byte order.
  * The parameter is declared unsigned int, not png_uint_16,
  * just to avoid potential problems on pre-ANSI C compilers.
  */
 
 /* Place a 16-bit number into a buffer in PNG byte order.
  * The parameter is declared unsigned int, not png_uint_16,
  * just to avoid potential problems on pre-ANSI C compilers.
  */

-void /* PRIVATE */
+void PNGAPI

 png_save_uint_16(png_bytep buf, unsigned int i)
 {
    buf[0] = (png_byte)((i >> 8) & 0xff);
 png_save_uint_16(png_bytep buf, unsigned int i)
 {
    buf[0] = (png_byte)((i >> 8) & 0xff);


@@ -64,6 +62,7 @@ void PNGAPI
 png_write_chunk(png_structp png_ptr, png_bytep chunk_name,
    png_bytep data, png_size_t length)
 {
 png_write_chunk(png_structp png_ptr, png_bytep chunk_name,
    png_bytep data, png_size_t length)
 {

+   if(png_ptr == NULL) return;

    png_write_chunk_start(png_ptr, chunk_name, (png_uint_32)length);
    png_write_chunk_data(png_ptr, data, length);
    png_write_chunk_end(png_ptr);
    png_write_chunk_start(png_ptr, chunk_name, (png_uint_32)length);
    png_write_chunk_data(png_ptr, data, length);
    png_write_chunk_end(png_ptr);


@@ -79,6 +78,7 @@ png_write_chunk_start(png_structp png_ptr, png_bytep chunk_name,
 {
    png_byte buf[4];
    png_debug2(0, "Writing %s chunk (%lu bytes)\n", chunk_name, length);
 {
    png_byte buf[4];
    png_debug2(0, "Writing %s chunk (%lu bytes)\n", chunk_name, length);

+   if(png_ptr == NULL) return;

 
    /* write the length */
    png_save_uint_32(buf, length);
 
    /* write the length */
    png_save_uint_32(buf, length);


@@ -100,6 +100,7 @@ void PNGAPI
 png_write_chunk_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
    /* write the data, and run the CRC over it */
 png_write_chunk_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
    /* write the data, and run the CRC over it */

+   if(png_ptr == NULL) return;

    if (data != NULL && length > 0)
    {
       png_calculate_crc(png_ptr, data, length);
    if (data != NULL && length > 0)
    {
       png_calculate_crc(png_ptr, data, length);


@@ -113,6 +114,8 @@ png_write_chunk_end(png_structp png_ptr)
 {
    png_byte buf[4];
 
 {
    png_byte buf[4];
 

+   if(png_ptr == NULL) return;
+

    /* write the crc */
    png_save_uint_32(buf, png_ptr->crc);
 
    /* write the crc */
    png_save_uint_32(buf, png_ptr->crc);
 


@@ -161,9 +164,11 @@ png_text_compress(png_structp png_ptr,
 {
    int ret;
 
 {
    int ret;
 

-   comp->num_output_ptr = comp->max_output_ptr = 0;
+   comp->num_output_ptr = 0;
+   comp->max_output_ptr = 0;

    comp->output_ptr = NULL;
    comp->input = NULL;
    comp->output_ptr = NULL;
    comp->input = NULL;

+   comp->input_len = 0;

 
    /* we may just want to pass the text right through */
    if (compression == PNG_TEXT_COMPRESSION_NONE)
 
    /* we may just want to pass the text right through */
    if (compression == PNG_TEXT_COMPRESSION_NONE)


@@ -177,7 +182,7 @@ png_text_compress(png_structp png_ptr,
    {
 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
       char msg[50];
    {
 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
       char msg[50];

-      sprintf(msg, "Unknown compression type %d", compression);
+      png_snprintf(msg, 50, "Unknown compression type %d", compression);

       png_warning(png_ptr, msg);
 #else
       png_warning(png_ptr, "Unknown compression type");
       png_warning(png_ptr, msg);
 #else
       png_warning(png_ptr, "Unknown compression type");


@@ -219,7 +224,7 @@ png_text_compress(png_structp png_ptr,
             png_error(png_ptr, "zlib error");
       }
       /* check to see if we need more room */
             png_error(png_ptr, "zlib error");
       }
       /* check to see if we need more room */

-      if (!png_ptr->zstream.avail_out && png_ptr->zstream.avail_in)
+      if (!(png_ptr->zstream.avail_out))

       {
          /* make sure the output array has room */
          if (comp->num_output_ptr >= comp->max_output_ptr)
       {
          /* make sure the output array has room */
          if (comp->num_output_ptr >= comp->max_output_ptr)


@@ -234,14 +239,16 @@ png_text_compress(png_structp png_ptr,
 
                old_ptr = comp->output_ptr;
                comp->output_ptr = (png_charpp)png_malloc(png_ptr,
 
                old_ptr = comp->output_ptr;
                comp->output_ptr = (png_charpp)png_malloc(png_ptr,

-                  (png_uint_32)(comp->max_output_ptr * sizeof (png_charpp)));
+                  (png_uint_32)(comp->max_output_ptr *
+                  png_sizeof (png_charpp)));

                png_memcpy(comp->output_ptr, old_ptr, old_max
                png_memcpy(comp->output_ptr, old_ptr, old_max

-                  * sizeof (png_charp));
+                  * png_sizeof (png_charp));

                png_free(png_ptr, old_ptr);
             }
             else
                comp->output_ptr = (png_charpp)png_malloc(png_ptr,
                png_free(png_ptr, old_ptr);
             }
             else
                comp->output_ptr = (png_charpp)png_malloc(png_ptr,

-                  (png_uint_32)(comp->max_output_ptr * sizeof (png_charp)));
+                  (png_uint_32)(comp->max_output_ptr *
+                  png_sizeof (png_charp)));

          }
 
          /* save the data */
          }
 
          /* save the data */


@@ -283,14 +290,16 @@ png_text_compress(png_structp png_ptr,
                   old_ptr = comp->output_ptr;
                   /* This could be optimized to realloc() */
                   comp->output_ptr = (png_charpp)png_malloc(png_ptr,
                   old_ptr = comp->output_ptr;
                   /* This could be optimized to realloc() */
                   comp->output_ptr = (png_charpp)png_malloc(png_ptr,

-                     (png_uint_32)(comp->max_output_ptr * sizeof (png_charpp)));
+                     (png_uint_32)(comp->max_output_ptr *
+                     png_sizeof (png_charpp)));

                   png_memcpy(comp->output_ptr, old_ptr,
                   png_memcpy(comp->output_ptr, old_ptr,

-                     old_max * sizeof (png_charp));
+                     old_max * png_sizeof (png_charp));

                   png_free(png_ptr, old_ptr);
                }
                else
                   comp->output_ptr = (png_charpp)png_malloc(png_ptr,
                   png_free(png_ptr, old_ptr);
                }
                else
                   comp->output_ptr = (png_charpp)png_malloc(png_ptr,

-                     (png_uint_32)(comp->max_output_ptr * sizeof (png_charp)));
+                     (png_uint_32)(comp->max_output_ptr *
+                     png_sizeof (png_charp)));

             }
 
             /* save off the data */
             }
 
             /* save off the data */


@@ -353,9 +362,9 @@ png_write_compressed_data_out(png_structp png_ptr, compression_state *comp)
       png_write_chunk_data(png_ptr, png_ptr->zbuf,
          png_ptr->zbuf_size - png_ptr->zstream.avail_out);
 
       png_write_chunk_data(png_ptr, png_ptr->zbuf,
          png_ptr->zbuf_size - png_ptr->zstream.avail_out);
 

-   /* reset zlib for another zTXt/iTXt or the image data */
+   /* reset zlib for another zTXt/iTXt or image data */

    deflateReset(&png_ptr->zstream);
    deflateReset(&png_ptr->zstream);

-
+   png_ptr->zstream.data_type = Z_BINARY;

 }
 #endif
 
 }
 #endif
 


@@ -464,11 +473,12 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
 #if defined(PNG_MNG_FEATURES_SUPPORTED)
    png_ptr->filter_type = (png_byte)filter_type;
 #endif
 #if defined(PNG_MNG_FEATURES_SUPPORTED)
    png_ptr->filter_type = (png_byte)filter_type;
 #endif

+   png_ptr->compression_type = (png_byte)compression_type;

    png_ptr->width = width;
    png_ptr->height = height;
 
    png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels);
    png_ptr->width = width;
    png_ptr->height = height;
 
    png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels);

-   png_ptr->rowbytes = ((width * (png_size_t)png_ptr->pixel_depth + 7) >> 3);
+   png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, width);

    /* set the usr info, so any transformations can modify it */
    png_ptr->usr_width = png_ptr->width;
    png_ptr->usr_bit_depth = png_ptr->bit_depth;
    /* set the usr info, so any transformations can modify it */
    png_ptr->usr_width = png_ptr->width;
    png_ptr->usr_bit_depth = png_ptr->bit_depth;


@@ -513,11 +523,15 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
       png_ptr->zlib_window_bits = 15;
    if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_METHOD))
       png_ptr->zlib_method = 8;
       png_ptr->zlib_window_bits = 15;
    if (!(png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_METHOD))
       png_ptr->zlib_method = 8;

-   deflateInit2(&png_ptr->zstream, png_ptr->zlib_level,
+   if (deflateInit2(&png_ptr->zstream, png_ptr->zlib_level,

       png_ptr->zlib_method, png_ptr->zlib_window_bits,
       png_ptr->zlib_method, png_ptr->zlib_window_bits,

-      png_ptr->zlib_mem_level, png_ptr->zlib_strategy);
+      png_ptr->zlib_mem_level, png_ptr->zlib_strategy) != Z_OK)
+       png_error(png_ptr, "zlib failed to initialize compressor");

    png_ptr->zstream.next_out = png_ptr->zbuf;
    png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
    png_ptr->zstream.next_out = png_ptr->zbuf;
    png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;

+   /* libpng is not interested in zstream.data_type */
+   /* set it to a predefined value, to avoid its evaluation inside zlib */
+   png_ptr->zstream.data_type = Z_BINARY;

 
    png_ptr->mode = PNG_HAVE_IHDR;
 }
 
    png_ptr->mode = PNG_HAVE_IHDR;
 }


@@ -564,7 +578,7 @@ png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal)
    png_ptr->num_palette = (png_uint_16)num_pal;
    png_debug1(3, "num_palette = %d\n", png_ptr->num_palette);
 
    png_ptr->num_palette = (png_uint_16)num_pal;
    png_debug1(3, "num_palette = %d\n", png_ptr->num_palette);
 

-   png_write_chunk_start(png_ptr, (png_bytep)png_PLTE, num_pal * 3);
+   png_write_chunk_start(png_ptr, png_PLTE, num_pal * 3);

 #ifndef PNG_NO_POINTER_INDEXING
    for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++)
    {
 #ifndef PNG_NO_POINTER_INDEXING
    for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++)
    {


@@ -596,6 +610,46 @@ png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
    PNG_IDAT;
 #endif
    png_debug(1, "in png_write_IDAT\n");
    PNG_IDAT;
 #endif
    png_debug(1, "in png_write_IDAT\n");

+
+   /* Optimize the CMF field in the zlib stream. */
+   /* This hack of the zlib stream is compliant to the stream specification. */
+   if (!(png_ptr->mode & PNG_HAVE_IDAT) &&
+       png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
+   {
+      unsigned int z_cmf = data[0];  /* zlib compression method and flags */
+      if ((z_cmf & 0x0f) == 8 && (z_cmf & 0xf0) <= 0x70)
+      {
+         /* Avoid memory underflows and multiplication overflows. */
+         /* The conditions below are practically always satisfied;
+            however, they still must be checked. */
+         if (length >= 2 &&
+             png_ptr->height < 16384 && png_ptr->width < 16384)
+         {
+            png_uint_32 uncompressed_idat_size = png_ptr->height *
+               ((png_ptr->width *
+               png_ptr->channels * png_ptr->bit_depth + 15) >> 3);
+            unsigned int z_cinfo = z_cmf >> 4;
+            unsigned int half_z_window_size = 1 << (z_cinfo + 7);
+            while (uncompressed_idat_size <= half_z_window_size &&
+                   half_z_window_size >= 256)
+            {
+               z_cinfo--;
+               half_z_window_size >>= 1;
+            }
+            z_cmf = (z_cmf & 0x0f) | (z_cinfo << 4);
+            if (data[0] != (png_byte)z_cmf)
+            {
+               data[0] = (png_byte)z_cmf;
+               data[1] &= 0xe0;
+               data[1] += (png_byte)(0x1f - ((z_cmf << 8) + data[1]) % 0x1f);
+            }
+         }
+      }
+      else
+         png_error(png_ptr,
+            "Invalid zlib compression method or flags in IDAT");
+   }
+

    png_write_chunk(png_ptr, (png_bytep)png_IDAT, data, length);
    png_ptr->mode |= PNG_HAVE_IDAT;
 }
    png_write_chunk(png_ptr, (png_bytep)png_IDAT, data, length);
    png_ptr->mode |= PNG_HAVE_IDAT;
 }


@@ -680,8 +734,16 @@ png_write_iCCP(png_structp png_ptr, png_charp name, int compression_type,
    png_size_t name_len;
    png_charp new_name;
    compression_state comp;
    png_size_t name_len;
    png_charp new_name;
    compression_state comp;

+   int embedded_profile_len = 0;

 
    png_debug(1, "in png_write_iCCP\n");
 
    png_debug(1, "in png_write_iCCP\n");

+
+   comp.num_output_ptr = 0;
+   comp.max_output_ptr = 0;
+   comp.output_ptr = NULL;
+   comp.input = NULL;
+   comp.input_len = 0;
+

    if (name == NULL || (name_len = png_check_keyword(png_ptr, name,
       &new_name)) == 0)
    {
    if (name == NULL || (name_len = png_check_keyword(png_ptr, name,
       &new_name)) == 0)
    {


@@ -695,12 +757,33 @@ png_write_iCCP(png_structp png_ptr, png_charp name, int compression_type,
    if (profile == NULL)
       profile_len = 0;
 
    if (profile == NULL)
       profile_len = 0;
 

+   if (profile_len > 3)
+      embedded_profile_len =
+          ((*( (png_bytep)profile  ))<<24) |
+          ((*( (png_bytep)profile+1))<<16) |
+          ((*( (png_bytep)profile+2))<< 8) |
+          ((*( (png_bytep)profile+3))    );
+
+   if (profile_len < embedded_profile_len)
+     {
+        png_warning(png_ptr,
+          "Embedded profile length too large in iCCP chunk");
+        return;
+     }
+
+   if (profile_len > embedded_profile_len)
+     {
+        png_warning(png_ptr,
+          "Truncating profile to actual length in iCCP chunk");
+        profile_len = embedded_profile_len;
+     }
+

    if (profile_len)
        profile_len = png_text_compress(png_ptr, profile, (png_size_t)profile_len,
           PNG_COMPRESSION_TYPE_BASE, &comp);
 
    /* make sure we include the NULL after the name and the compression type */
    if (profile_len)
        profile_len = png_text_compress(png_ptr, profile, (png_size_t)profile_len,
           PNG_COMPRESSION_TYPE_BASE, &comp);
 
    /* make sure we include the NULL after the name and the compression type */

-   png_write_chunk_start(png_ptr, (png_bytep)png_iCCP,
+   png_write_chunk_start(png_ptr, png_iCCP,

           (png_uint_32)name_len+profile_len+2);
    new_name[name_len+1]=0x00;
    png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 2);
           (png_uint_32)name_len+profile_len+2);
    new_name[name_len+1]=0x00;
    png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 2);


@@ -740,7 +823,7 @@ png_write_sPLT(png_structp png_ptr, png_sPLT_tp spalette)
    }
 
    /* make sure we include the NULL after the name */
    }
 
    /* make sure we include the NULL after the name */

-   png_write_chunk_start(png_ptr, (png_bytep)png_sPLT,
+   png_write_chunk_start(png_ptr, png_sPLT,

           (png_uint_32)(name_len + 2 + palette_size));
    png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 1);
    png_write_chunk_data(png_ptr, (png_bytep)&spalette->depth, 1);
           (png_uint_32)(name_len + 2 + palette_size));
    png_write_chunk_data(png_ptr, (png_bytep)new_name, name_len + 1);
    png_write_chunk_data(png_ptr, (png_bytep)&spalette->depth, 1);


@@ -882,8 +965,7 @@ png_write_cHRM(png_structp png_ptr, double white_x, double white_y,
    itemp = (png_uint_32)(white_y * 100000.0 + 0.5);
    png_save_uint_32(buf + 4, itemp);
 
    itemp = (png_uint_32)(white_y * 100000.0 + 0.5);
    png_save_uint_32(buf + 4, itemp);
 

-   if (red_x < 0 || red_x > 0.8 || red_y < 0 || red_y > 0.8 ||
-       red_x + red_y > 1.0)
+   if (red_x < 0 ||  red_y < 0 || red_x + red_y > 1.0)

    {
       png_warning(png_ptr, "Invalid cHRM red point specified");
       return;
    {
       png_warning(png_ptr, "Invalid cHRM red point specified");
       return;


@@ -893,8 +975,7 @@ png_write_cHRM(png_structp png_ptr, double white_x, double white_y,
    itemp = (png_uint_32)(red_y * 100000.0 + 0.5);
    png_save_uint_32(buf + 12, itemp);
 
    itemp = (png_uint_32)(red_y * 100000.0 + 0.5);
    png_save_uint_32(buf + 12, itemp);
 

-   if (green_x < 0 || green_x > 0.8 || green_y < 0 || green_y > 0.8 ||
-       green_x + green_y > 1.0)
+   if (green_x < 0 || green_y < 0 || green_x + green_y > 1.0)

    {
       png_warning(png_ptr, "Invalid cHRM green point specified");
       return;
    {
       png_warning(png_ptr, "Invalid cHRM green point specified");
       return;


@@ -904,8 +985,7 @@ png_write_cHRM(png_structp png_ptr, double white_x, double white_y,
    itemp = (png_uint_32)(green_y * 100000.0 + 0.5);
    png_save_uint_32(buf + 20, itemp);
 
    itemp = (png_uint_32)(green_y * 100000.0 + 0.5);
    png_save_uint_32(buf + 20, itemp);
 

-   if (blue_x < 0 || blue_x > 0.8 || blue_y < 0 || blue_y > 0.8 ||
-       blue_x + blue_y > 1.0)
+   if (blue_x < 0 || blue_y < 0 || blue_x + blue_y > 1.0)

    {
       png_warning(png_ptr, "Invalid cHRM blue point specified");
       return;
    {
       png_warning(png_ptr, "Invalid cHRM blue point specified");
       return;


@@ -943,7 +1023,7 @@ png_write_cHRM_fixed(png_structp png_ptr, png_fixed_point white_x,
    png_save_uint_32(buf, (png_uint_32)white_x);
    png_save_uint_32(buf + 4, (png_uint_32)white_y);
 
    png_save_uint_32(buf, (png_uint_32)white_x);
    png_save_uint_32(buf + 4, (png_uint_32)white_y);
 

-   if (red_x > 80000L || red_y > 80000L || red_x + red_y > 100000L)
+   if (red_x + red_y > 100000L)

    {
       png_warning(png_ptr, "Invalid cHRM fixed red point specified");
       return;
    {
       png_warning(png_ptr, "Invalid cHRM fixed red point specified");
       return;


@@ -951,7 +1031,7 @@ png_write_cHRM_fixed(png_structp png_ptr, png_fixed_point white_x,
    png_save_uint_32(buf + 8, (png_uint_32)red_x);
    png_save_uint_32(buf + 12, (png_uint_32)red_y);
 
    png_save_uint_32(buf + 8, (png_uint_32)red_x);
    png_save_uint_32(buf + 12, (png_uint_32)red_y);
 

-   if (green_x > 80000L || green_y > 80000L || green_x + green_y > 100000L)
+   if (green_x + green_y > 100000L)

    {
       png_warning(png_ptr, "Invalid fixed cHRM green point specified");
       return;
    {
       png_warning(png_ptr, "Invalid fixed cHRM green point specified");
       return;


@@ -959,7 +1039,7 @@ png_write_cHRM_fixed(png_structp png_ptr, png_fixed_point white_x,
    png_save_uint_32(buf + 16, (png_uint_32)green_x);
    png_save_uint_32(buf + 20, (png_uint_32)green_y);
 
    png_save_uint_32(buf + 16, (png_uint_32)green_x);
    png_save_uint_32(buf + 20, (png_uint_32)green_y);
 

-   if (blue_x > 80000L || blue_y > 80000L || blue_x + blue_y > 100000L)
+   if (blue_x + blue_y > 100000L)

    {
       png_warning(png_ptr, "Invalid fixed cHRM blue point specified");
       return;
    {
       png_warning(png_ptr, "Invalid fixed cHRM blue point specified");
       return;


@@ -1100,7 +1180,7 @@ png_write_hIST(png_structp png_ptr, png_uint_16p hist, int num_hist)
       return;
    }
 
       return;
    }
 

-   png_write_chunk_start(png_ptr, (png_bytep)png_hIST, (png_uint_32)(num_hist * 2));
+   png_write_chunk_start(png_ptr, png_hIST, (png_uint_32)(num_hist * 2));

    for (i = 0; i < num_hist; i++)
    {
       png_save_uint_16(buf, hist[i]);
    for (i = 0; i < num_hist; i++)
    {
       png_save_uint_16(buf, hist[i]);


@@ -1141,17 +1221,24 @@ png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key)
 
    png_debug1(2, "Keyword to be checked is '%s'\n", key);
 
 
    png_debug1(2, "Keyword to be checked is '%s'\n", key);
 

-   *new_key = (png_charp)png_malloc(png_ptr, (png_uint_32)(key_len + 2));
+   *new_key = (png_charp)png_malloc_warn(png_ptr, (png_uint_32)(key_len + 2));
+   if (*new_key == NULL)
+   {
+      png_warning(png_ptr, "Out of memory while procesing keyword");
+      return ((png_size_t)0);
+   }

 
    /* Replace non-printing characters with a blank and print a warning */
    for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++)
    {
 
    /* Replace non-printing characters with a blank and print a warning */
    for (kp = key, dp = *new_key; *kp != '\0'; kp++, dp++)
    {

-      if (*kp < 0x20 || (*kp > 0x7E && (png_byte)*kp < 0xA1))
+      if ((png_byte)*kp < 0x20 ||
+         ((png_byte)*kp > 0x7E && (png_byte)*kp < 0xA1))

       {
 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
          char msg[40];
 
       {
 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
          char msg[40];
 

-         sprintf(msg, "invalid keyword character 0x%02X", *kp);
+         png_snprintf(msg, 40,
+           "invalid keyword character 0x%02X", (png_byte)*kp);

          png_warning(png_ptr, msg);
 #else
          png_warning(png_ptr, "invalid character in keyword");
          png_warning(png_ptr, msg);
 #else
          png_warning(png_ptr, "invalid character in keyword");


@@ -1291,6 +1378,12 @@ png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
 
    png_debug(1, "in png_write_zTXt\n");
 
 
    png_debug(1, "in png_write_zTXt\n");
 

+   comp.num_output_ptr = 0;
+   comp.max_output_ptr = 0;
+   comp.output_ptr = NULL;
+   comp.input = NULL;
+   comp.input_len = 0;
+

    if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
    {
       png_warning(png_ptr, "Empty keyword in zTXt chunk");
    if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
    {
       png_warning(png_ptr, "Empty keyword in zTXt chunk");


@@ -1306,8 +1399,6 @@ png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
 
    text_len = png_strlen(text);
 
 
    text_len = png_strlen(text);
 

-   png_free(png_ptr, new_key);
-

    /* compute the compressed data; do it now for the length */
    text_len = png_text_compress(png_ptr, text, text_len, compression,
        &comp);
    /* compute the compressed data; do it now for the length */
    text_len = png_text_compress(png_ptr, text, text_len, compression,
        &comp);


@@ -1316,7 +1407,9 @@ png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
    png_write_chunk_start(png_ptr, (png_bytep)png_zTXt, (png_uint_32)
       (key_len+text_len+2));
    /* write key */
    png_write_chunk_start(png_ptr, (png_bytep)png_zTXt, (png_uint_32)
       (key_len+text_len+2));
    /* write key */

-   png_write_chunk_data(png_ptr, (png_bytep)key, key_len + 1);
+   png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
+   png_free(png_ptr, new_key);
+

    buf[0] = (png_byte)compression;
    /* write compression */
    png_write_chunk_data(png_ptr, (png_bytep)buf, (png_size_t)1);
    buf[0] = (png_byte)compression;
    /* write compression */
    png_write_chunk_data(png_ptr, (png_bytep)buf, (png_size_t)1);


@@ -1344,6 +1437,11 @@ png_write_iTXt(png_structp png_ptr, int compression, png_charp key,
 
    png_debug(1, "in png_write_iTXt\n");
 
 
    png_debug(1, "in png_write_iTXt\n");
 

+   comp.num_output_ptr = 0;
+   comp.max_output_ptr = 0;
+   comp.output_ptr = NULL;
+   comp.input = NULL;
+

    if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
    {
       png_warning(png_ptr, "Empty keyword in iTXt chunk");
    if (key == NULL || (key_len = png_check_keyword(png_ptr, key, &new_key))==0)
    {
       png_warning(png_ptr, "Empty keyword in iTXt chunk");


@@ -1353,7 +1451,7 @@ png_write_iTXt(png_structp png_ptr, int compression, png_charp key,
    {
       png_warning(png_ptr, "Empty language field in iTXt chunk");
       new_lang = NULL;
    {
       png_warning(png_ptr, "Empty language field in iTXt chunk");
       new_lang = NULL;

-      lang_len = 0;      
+      lang_len = 0;

    }
 
    if (lang_key == NULL)
    }
 
    if (lang_key == NULL)


@@ -1431,10 +1529,9 @@ png_write_oFFs(png_structp png_ptr, png_int_32 x_offset, png_int_32 y_offset,
    png_save_int_32(buf + 4, y_offset);
    buf[8] = (png_byte)unit_type;
 
    png_save_int_32(buf + 4, y_offset);
    buf[8] = (png_byte)unit_type;
 

-   png_write_chunk(png_ptr, (png_bytep)png_oFFs, buf, (png_size_t)9);
+   png_write_chunk(png_ptr, png_oFFs, buf, (png_size_t)9);

 }
 #endif
 }
 #endif

-

 #if defined(PNG_WRITE_pCAL_SUPPORTED)
 /* write the pCAL chunk (described in the PNG extensions document) */
 void /* PRIVATE */
 #if defined(PNG_WRITE_pCAL_SUPPORTED)
 /* write the pCAL chunk (described in the PNG extensions document) */
 void /* PRIVATE */


@@ -1461,7 +1558,7 @@ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
    total_len = purpose_len + units_len + 10;
 
    params_len = (png_uint_32p)png_malloc(png_ptr, (png_uint_32)(nparams
    total_len = purpose_len + units_len + 10;
 
    params_len = (png_uint_32p)png_malloc(png_ptr, (png_uint_32)(nparams

-      *sizeof(png_uint_32)));
+      *png_sizeof(png_uint_32)));

 
    /* Find the length of each parameter, making sure we don't count the
       null terminator for the last parameter. */
 
    /* Find the length of each parameter, making sure we don't count the
       null terminator for the last parameter. */


@@ -1473,7 +1570,7 @@ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
    }
 
    png_debug1(3, "pCAL total length = %d\n", (int)total_len);
    }
 
    png_debug1(3, "pCAL total length = %d\n", (int)total_len);

-   png_write_chunk_start(png_ptr, (png_bytep)png_pCAL, (png_uint_32)total_len);
+   png_write_chunk_start(png_ptr, png_pCAL, (png_uint_32)total_len);

    png_write_chunk_data(png_ptr, (png_bytep)new_purpose, purpose_len);
    png_save_int_32(buf, X0);
    png_save_int_32(buf + 4, X1);
    png_write_chunk_data(png_ptr, (png_bytep)new_purpose, purpose_len);
    png_save_int_32(buf, X0);
    png_save_int_32(buf + 4, X1);


@@ -1499,38 +1596,41 @@ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
 /* write the sCAL chunk */
 #if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
 void /* PRIVATE */
 /* write the sCAL chunk */
 #if defined(PNG_FLOATING_POINT_SUPPORTED) && !defined(PNG_NO_STDIO)
 void /* PRIVATE */

-png_write_sCAL(png_structp png_ptr, int unit, double width,double height)
+png_write_sCAL(png_structp png_ptr, int unit, double width, double height)

 {
 #ifdef PNG_USE_LOCAL_ARRAYS
    PNG_sCAL;
 #endif
 {
 #ifdef PNG_USE_LOCAL_ARRAYS
    PNG_sCAL;
 #endif

+   char buf[64];

    png_size_t total_len;
    png_size_t total_len;

-   char wbuf[32], hbuf[32];

 
    png_debug(1, "in png_write_sCAL\n");
 
 
    png_debug(1, "in png_write_sCAL\n");
 

+   buf[0] = (char)unit;

 #if defined(_WIN32_WCE)
 /* sprintf() function is not supported on WindowsCE */
    {
       wchar_t wc_buf[32];
 #if defined(_WIN32_WCE)
 /* sprintf() function is not supported on WindowsCE */
    {
       wchar_t wc_buf[32];

+      size_t wc_len;

       swprintf(wc_buf, TEXT("%12.12e"), width);
       swprintf(wc_buf, TEXT("%12.12e"), width);

-      WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, wbuf, 32, NULL, NULL);
+      wc_len = wcslen(wc_buf);
+      WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, buf + 1, wc_len, NULL, NULL);
+      total_len = wc_len + 2;

       swprintf(wc_buf, TEXT("%12.12e"), height);
       swprintf(wc_buf, TEXT("%12.12e"), height);

-      WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, hbuf, 32, NULL, NULL);
+      wc_len = wcslen(wc_buf);
+      WideCharToMultiByte(CP_ACP, 0, wc_buf, -1, buf + total_len, wc_len,
+         NULL, NULL);
+      total_len += wc_len;

    }
 #else
    }
 #else

-   sprintf(wbuf, "%12.12e", width);
-   sprintf(hbuf, "%12.12e", height);
+   png_snprintf(buf + 1, 63, "%12.12e", width);
+   total_len = 1 + png_strlen(buf + 1) + 1;
+   png_snprintf(buf + total_len, 64-total_len, "%12.12e", height);
+   total_len += png_strlen(buf + total_len);

 #endif
 #endif

-   total_len = 1 + png_strlen(wbuf)+1 + png_strlen(hbuf);

 
 

-   png_debug1(3, "sCAL total length = %d\n", (int)total_len);
-   png_write_chunk_start(png_ptr, (png_bytep)png_sCAL, (png_uint_32)total_len);
-   png_write_chunk_data(png_ptr, (png_bytep)&unit, 1);
-   png_write_chunk_data(png_ptr, (png_bytep)wbuf, png_strlen(wbuf)+1);
-   png_write_chunk_data(png_ptr, (png_bytep)hbuf, png_strlen(hbuf));
-
-   png_write_chunk_end(png_ptr);
+   png_debug1(3, "sCAL total length = %u\n", (unsigned int)total_len);
+   png_write_chunk(png_ptr, png_sCAL, (png_bytep)buf, total_len);

 }
 #else
 #ifdef PNG_FIXED_POINT_SUPPORTED
 }
 #else
 #ifdef PNG_FIXED_POINT_SUPPORTED


@@ -1541,22 +1641,26 @@ png_write_sCAL_s(png_structp png_ptr, int unit, png_charp width,
 #ifdef PNG_USE_LOCAL_ARRAYS
    PNG_sCAL;
 #endif
 #ifdef PNG_USE_LOCAL_ARRAYS
    PNG_sCAL;
 #endif

-   png_size_t total_len;
-   char wbuf[32], hbuf[32];
+   png_byte buf[64];
+   png_size_t wlen, hlen, total_len;

 
    png_debug(1, "in png_write_sCAL_s\n");
 
 
    png_debug(1, "in png_write_sCAL_s\n");
 

-   png_strcpy(wbuf,(const char *)width);
-   png_strcpy(hbuf,(const char *)height);
-   total_len = 1 + png_strlen(wbuf)+1 + png_strlen(hbuf);
+   wlen = png_strlen(width);
+   hlen = png_strlen(height);
+   total_len = wlen + hlen + 2;
+   if (total_len > 64)
+   {
+      png_warning(png_ptr, "Can't write sCAL (buffer too small)");
+      return;
+   }

 
 

-   png_debug1(3, "sCAL total length = %d\n", total_len);
-   png_write_chunk_start(png_ptr, (png_bytep)png_sCAL, (png_uint_32)total_len);
-   png_write_chunk_data(png_ptr, (png_bytep)&unit, 1);
-   png_write_chunk_data(png_ptr, (png_bytep)wbuf, png_strlen(wbuf)+1);
-   png_write_chunk_data(png_ptr, (png_bytep)hbuf, png_strlen(hbuf));
+   buf[0] = (png_byte)unit;
+   png_memcpy(buf + 1, width, wlen + 1);      /* append the '\0' here */
+   png_memcpy(buf + wlen + 2, height, hlen);  /* do NOT append the '\0' here */

 
 

-   png_write_chunk_end(png_ptr);
+   png_debug1(3, "sCAL total length = %u\n", (unsigned int)total_len);
+   png_write_chunk(png_ptr, png_sCAL, buf, total_len);

 }
 #endif
 #endif
 }
 #endif
 #endif


@@ -1582,7 +1686,7 @@ png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit,
    png_save_uint_32(buf + 4, y_pixels_per_unit);
    buf[8] = (png_byte)unit_type;
 
    png_save_uint_32(buf + 4, y_pixels_per_unit);
    buf[8] = (png_byte)unit_type;
 

-   png_write_chunk(png_ptr, (png_bytep)png_pHYs, buf, (png_size_t)9);
+   png_write_chunk(png_ptr, png_pHYs, buf, (png_size_t)9);

 }
 #endif
 
 }
 #endif
 


@@ -1614,7 +1718,7 @@ png_write_tIME(png_structp png_ptr, png_timep mod_time)
    buf[5] = mod_time->minute;
    buf[6] = mod_time->second;
 
    buf[5] = mod_time->minute;
    buf[6] = mod_time->second;
 

-   png_write_chunk(png_ptr, (png_bytep)png_tIME, buf, (png_size_t)7);
+   png_write_chunk(png_ptr, png_tIME, buf, (png_size_t)7);

 }
 #endif
 
 }
 #endif
 


@@ -1622,6 +1726,7 @@ png_write_tIME(png_structp png_ptr, png_timep mod_time)
 void /* PRIVATE */
 png_write_start_row(png_structp png_ptr)
 {
 void /* PRIVATE */
 png_write_start_row(png_structp png_ptr)
 {

+#ifdef PNG_WRITE_INTERLACING_SUPPORTED

 #ifdef PNG_USE_LOCAL_ARRAYS
    /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
 
 #ifdef PNG_USE_LOCAL_ARRAYS
    /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
 


@@ -1636,18 +1741,20 @@ png_write_start_row(png_structp png_ptr)
 
    /* offset to next interlace block in the y direction */
    int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
 
    /* offset to next interlace block in the y direction */
    int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};

+#endif

 #endif
 
    png_size_t buf_size;
 
    png_debug(1, "in png_write_start_row\n");
 #endif
 
    png_size_t buf_size;
 
    png_debug(1, "in png_write_start_row\n");

-   buf_size = (png_size_t)(((png_ptr->width * png_ptr->usr_channels *
-                            png_ptr->usr_bit_depth + 7) >> 3) + 1);
+   buf_size = (png_size_t)(PNG_ROWBYTES(
+      png_ptr->usr_channels*png_ptr->usr_bit_depth,png_ptr->width)+1);

 
    /* set up row buffer */
    png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
    png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE;
 
 
    /* set up row buffer */
    png_ptr->row_buf = (png_bytep)png_malloc(png_ptr, (png_uint_32)buf_size);
    png_ptr->row_buf[0] = PNG_FILTER_VALUE_NONE;
 

+#ifndef PNG_NO_WRITE_FILTERING

    /* set up filtering buffer, if using this filter */
    if (png_ptr->do_filter & PNG_FILTER_SUB)
    {
    /* set up filtering buffer, if using this filter */
    if (png_ptr->do_filter & PNG_FILTER_SUB)
    {


@@ -1665,7 +1772,7 @@ png_write_start_row(png_structp png_ptr)
 
       if (png_ptr->do_filter & PNG_FILTER_UP)
       {
 
       if (png_ptr->do_filter & PNG_FILTER_UP)
       {

-         png_ptr->up_row = (png_bytep )png_malloc(png_ptr,
+         png_ptr->up_row = (png_bytep)png_malloc(png_ptr,

             (png_ptr->rowbytes + 1));
          png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
       }
             (png_ptr->rowbytes + 1));
          png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
       }


@@ -1679,10 +1786,11 @@ png_write_start_row(png_structp png_ptr)
 
       if (png_ptr->do_filter & PNG_FILTER_PAETH)
       {
 
       if (png_ptr->do_filter & PNG_FILTER_PAETH)
       {

-         png_ptr->paeth_row = (png_bytep )png_malloc(png_ptr,
+         png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,

             (png_ptr->rowbytes + 1));
          png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
       }
             (png_ptr->rowbytes + 1));
          png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
       }

+#endif /* PNG_NO_WRITE_FILTERING */

    }
 
 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
    }
 
 #ifdef PNG_WRITE_INTERLACING_SUPPORTED


@@ -1716,6 +1824,7 @@ png_write_start_row(png_structp png_ptr)
 void /* PRIVATE */
 png_write_finish_row(png_structp png_ptr)
 {
 void /* PRIVATE */
 png_write_finish_row(png_structp png_ptr)
 {

+#ifdef PNG_WRITE_INTERLACING_SUPPORTED

 #ifdef PNG_USE_LOCAL_ARRAYS
    /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
 
 #ifdef PNG_USE_LOCAL_ARRAYS
    /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
 


@@ -1730,6 +1839,7 @@ png_write_finish_row(png_structp png_ptr)
 
    /* offset to next interlace block in the y direction */
    int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
 
    /* offset to next interlace block in the y direction */
    int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};

+#endif

 #endif
 
    int ret;
 #endif
 
    int ret;


@@ -1778,9 +1888,8 @@ png_write_finish_row(png_structp png_ptr)
       {
          if (png_ptr->prev_row != NULL)
             png_memset(png_ptr->prev_row, 0,
       {
          if (png_ptr->prev_row != NULL)
             png_memset(png_ptr->prev_row, 0,

-               (png_size_t) (((png_uint_32)png_ptr->usr_channels *
-               (png_uint_32)png_ptr->usr_bit_depth *
-               png_ptr->width + 7) >> 3) + 1);
+               (png_size_t)(PNG_ROWBYTES(png_ptr->usr_channels*
+               png_ptr->usr_bit_depth,png_ptr->width))+1);

          return;
       }
    }
          return;
       }
    }


@@ -1820,6 +1929,7 @@ png_write_finish_row(png_structp png_ptr)
    }
 
    deflateReset(&png_ptr->zstream);
    }
 
    deflateReset(&png_ptr->zstream);

+   png_ptr->zstream.data_type = Z_BINARY;

 }
 
 #if defined(PNG_WRITE_INTERLACING_SUPPORTED)
 }
 
 #if defined(PNG_WRITE_INTERLACING_SUPPORTED)


@@ -1987,8 +2097,8 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
          png_pass_inc[pass] - 1 -
          png_pass_start[pass]) /
          png_pass_inc[pass];
          png_pass_inc[pass] - 1 -
          png_pass_start[pass]) /
          png_pass_inc[pass];

-         row_info->rowbytes = ((row_info->width *
-            row_info->pixel_depth + 7) >> 3);
+         row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth,
+            row_info->width);

    }
 }
 #endif
    }
 }
 #endif


@@ -1997,14 +2107,16 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
  * been specified by the application, and then writes the row out with the
  * chosen filter.
  */
  * been specified by the application, and then writes the row out with the
  * chosen filter.
  */

-#define PNG_MAXSUM (~((png_uint_32)0) >> 1)
+#define PNG_MAXSUM (((png_uint_32)(-1)) >> 1)

 #define PNG_HISHIFT 10
 #define PNG_LOMASK ((png_uint_32)0xffffL)
 #define PNG_HIMASK ((png_uint_32)(~PNG_LOMASK >> PNG_HISHIFT))
 void /* PRIVATE */
 png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
 {
 #define PNG_HISHIFT 10
 #define PNG_LOMASK ((png_uint_32)0xffffL)
 #define PNG_HIMASK ((png_uint_32)(~PNG_LOMASK >> PNG_HISHIFT))
 void /* PRIVATE */
 png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
 {

-   png_bytep prev_row, best_row, row_buf;
+   png_bytep best_row;
+#ifndef PNG_NO_WRITE_FILTER
+   png_bytep prev_row, row_buf;

    png_uint_32 mins, bpp;
    png_byte filter_to_do = png_ptr->do_filter;
    png_uint_32 row_bytes = row_info->rowbytes;
    png_uint_32 mins, bpp;
    png_byte filter_to_do = png_ptr->do_filter;
    png_uint_32 row_bytes = row_info->rowbytes;


@@ -2014,10 +2126,13 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
 
    png_debug(1, "in png_write_find_filter\n");
    /* find out how many bytes offset each pixel is */
 
    png_debug(1, "in png_write_find_filter\n");
    /* find out how many bytes offset each pixel is */

-   bpp = (row_info->pixel_depth + 7) / 8;
+   bpp = (row_info->pixel_depth + 7) >> 3;

 
    prev_row = png_ptr->prev_row;
 
    prev_row = png_ptr->prev_row;

-   best_row = row_buf = png_ptr->row_buf;
+#endif
+   best_row = png_ptr->row_buf;
+#ifndef PNG_NO_WRITE_FILTER
+   row_buf = best_row;

    mins = PNG_MAXSUM;
 
    /* The prediction method we use is to find which method provides the
    mins = PNG_MAXSUM;
 
    /* The prediction method we use is to find which method provides the


@@ -2165,7 +2280,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
 
          sum += (v < 128) ? v : 256 - v;
       }
 
          sum += (v < 128) ? v : 256 - v;
       }

-      for (lp = row_buf + 1; i < row_info->rowbytes;
+      for (lp = row_buf + 1; i < row_bytes;

          i++, rp++, lp++, dp++)
       {
          v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
          i++, rp++, lp++, dp++)
       {
          v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);


@@ -2592,11 +2707,12 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
          best_row = png_ptr->paeth_row;
       }
    }
          best_row = png_ptr->paeth_row;
       }
    }

-
+#endif /* PNG_NO_WRITE_FILTER */

    /* Do the actual writing of the filtered row data from the chosen filter. */
 
    png_write_filtered_row(png_ptr, best_row);
 
    /* Do the actual writing of the filtered row data from the chosen filter. */
 
    png_write_filtered_row(png_ptr, best_row);
 

+#ifndef PNG_NO_WRITE_FILTER

 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
    /* Save the type of filter we picked this time for future calculations */
    if (png_ptr->num_prev_filters > 0)
 #if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)
    /* Save the type of filter we picked this time for future calculations */
    if (png_ptr->num_prev_filters > 0)


@@ -2609,6 +2725,7 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
       png_ptr->prev_filters[j] = best_row[0];
    }
 #endif
       png_ptr->prev_filters[j] = best_row[0];
    }
 #endif

+#endif /* PNG_NO_WRITE_FILTER */

 }
 
 
 }