Imported from libpng-1.4.0beta20.tar
diff --git a/pngset.c b/pngset.c
index ea2ef03..f9f162d 100644
--- a/pngset.c
+++ b/pngset.c
@@ -1,9 +1,9 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * Last changed in libpng 1.4.0 May 15, 2007
+ * Last changed in libpng 1.4.0 [July 10, 2008]
  * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2007 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2008 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -14,9 +14,8 @@
  */
 
 #include "png.h"
-#include "pngpriv.h"
-
 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+#include "pngpriv.h"
 
 #if defined(PNG_bKGD_SUPPORTED)
 void PNGAPI
@@ -26,7 +25,7 @@
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   png_memcpy(&(info_ptr->background), background, sizeof(png_color_16));
+   png_memcpy(&(info_ptr->background), background, png_sizeof(png_color_16));
    info_ptr->valid |= PNG_INFO_bKGD;
 }
 #endif
@@ -41,7 +40,13 @@
    png_debug1(1, "in %s storage function\n", "cHRM");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
-
+   if (!(white_x || white_y || red_x || red_y || green_x || green_y ||
+       blue_x || blue_y))
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set all-zero chromaticity values");
+      return;
+   }
    if (white_x < 0.0 || white_y < 0.0 ||
          red_x < 0.0 ||   red_y < 0.0 ||
        green_x < 0.0 || green_y < 0.0 ||
@@ -93,6 +98,13 @@
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
+   if (!(white_x || white_y || red_x || red_y || green_x || green_y ||
+       blue_x || blue_y))
+   {
+      png_warning(png_ptr,
+        "Ignoring attempt to set all-zero chromaticity values");
+      return;
+   }
    if (white_x < 0 || white_y < 0 ||
          red_x < 0 ||   red_y < 0 ||
        green_x < 0 || green_y < 0 ||
@@ -102,25 +114,14 @@
         "Ignoring attempt to set negative chromaticity value");
       return;
    }
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-   if (white_x > (double) PNG_UINT_31_MAX ||
-       white_y > (double) PNG_UINT_31_MAX ||
-         red_x > (double) PNG_UINT_31_MAX ||
-         red_y > (double) PNG_UINT_31_MAX ||
-       green_x > (double) PNG_UINT_31_MAX ||
-       green_y > (double) PNG_UINT_31_MAX ||
-        blue_x > (double) PNG_UINT_31_MAX ||
-        blue_y > (double) PNG_UINT_31_MAX)
-#else
-   if (white_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
-       white_y > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
-         red_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
-         red_y > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
-       green_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
-       green_y > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
-        blue_x > (png_fixed_point) PNG_UINT_31_MAX/100000L ||
-        blue_y > (png_fixed_point) PNG_UINT_31_MAX/100000L)
-#endif
+   if (white_x > (png_fixed_point) PNG_UINT_31_MAX ||
+       white_y > (png_fixed_point) PNG_UINT_31_MAX ||
+         red_x > (png_fixed_point) PNG_UINT_31_MAX ||
+         red_y > (png_fixed_point) PNG_UINT_31_MAX ||
+       green_x > (png_fixed_point) PNG_UINT_31_MAX ||
+       green_y > (png_fixed_point) PNG_UINT_31_MAX ||
+        blue_x > (png_fixed_point) PNG_UINT_31_MAX ||
+        blue_y > (png_fixed_point) PNG_UINT_31_MAX )
    {
       png_warning(png_ptr,
         "Ignoring attempt to set chromaticity value exceeding 21474.83");
@@ -172,7 +173,7 @@
    info_ptr->int_gamma = (int)(gamma*100000.+.5);
 #endif
    info_ptr->valid |= PNG_INFO_gAMA;
-   if(gamma == 0.0)
+   if (gamma == 0.0)
       png_warning(png_ptr, "Setting gamma=0");
 }
 #endif
@@ -196,7 +197,7 @@
      if (int_gamma < 0)
      {
        png_warning(png_ptr, "Setting negative gamma to zero");
-       gamma=0;
+       gamma = 0;
      }
      else
        gamma=int_gamma;
@@ -208,7 +209,7 @@
    info_ptr->int_gamma = gamma;
 #endif
    info_ptr->valid |= PNG_INFO_gAMA;
-   if(gamma == 0)
+   if (gamma == 0)
       png_warning(png_ptr, "Setting gamma=0");
 }
 #endif
@@ -222,7 +223,7 @@
    png_debug1(1, "in %s storage function\n", "hIST");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
-   if (info_ptr->num_palette <= 0 || info_ptr->num_palette
+   if (info_ptr->num_palette == 0 || info_ptr->num_palette
        > PNG_MAX_PALETTE_LENGTH)
    {
        png_warning(png_ptr,
@@ -236,7 +237,7 @@
    /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in version
       1.2.1 */
    png_ptr->hist = (png_uint_16p)png_malloc_warn(png_ptr,
-      PNG_MAX_PALETTE_LENGTH * sizeof(png_uint_16));
+      PNG_MAX_PALETTE_LENGTH * png_sizeof(png_uint_16));
    if (png_ptr->hist == NULL)
      {
        png_warning(png_ptr, "Insufficient memory for hIST chunk data");
@@ -317,21 +318,21 @@
     * 4. The filter_method is 64 and
     * 5. The color_type is RGB or RGBA
     */
-   if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&png_ptr->mng_features_permitted)
-      png_warning(png_ptr,"MNG features are not allowed in a PNG datastream");
-   if(filter_type != PNG_FILTER_TYPE_BASE)
+   if ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&png_ptr->mng_features_permitted)
+      png_warning(png_ptr, "MNG features are not allowed in a PNG datastream");
+   if (filter_type != PNG_FILTER_TYPE_BASE)
    {
-     if(!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+     if (!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
         (filter_type == PNG_INTRAPIXEL_DIFFERENCING) &&
         ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
         (color_type == PNG_COLOR_TYPE_RGB ||
          color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
         png_error(png_ptr, "Unknown filter method in IHDR");
-     if(png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)
+     if (png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)
         png_warning(png_ptr, "Invalid filter method in IHDR");
    }
 #else
-   if(filter_type != PNG_FILTER_TYPE_BASE)
+   if (filter_type != PNG_FILTER_TYPE_BASE)
       png_error(png_ptr, "Unknown filter method in IHDR");
 #endif
 
@@ -361,7 +362,7 @@
                  - 8)       /* extra max_pixel_depth pad */
       info_ptr->rowbytes = 0;
    else
-      info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth,width);
+      info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
 }
 
 #if defined(PNG_oFFs_SUPPORTED)
@@ -395,11 +396,11 @@
 
    length = png_strlen(purpose) + 1;
    png_debug1(3, "allocating purpose for info (%lu bytes)\n",
-     (unsigned long) length);
+     (unsigned long)length);
    info_ptr->pcal_purpose = (png_charp)png_malloc_warn(png_ptr, length);
    if (info_ptr->pcal_purpose == NULL)
    {
-      png_warning(png_ptr, "Insufficient memory for pCAL purpose");
+       png_warning(png_ptr, "Insufficient memory for pCAL purpose");
       return;
    }
    png_memcpy(info_ptr->pcal_purpose, purpose, length);
@@ -411,21 +412,21 @@
    info_ptr->pcal_nparams = (png_byte)nparams;
 
    length = png_strlen(units) + 1;
-   png_debug1(3, "allocating units for info (%lu bytes)\n", 
+   png_debug1(3, "allocating units for info (%lu bytes)\n",
      (unsigned long)length);
    info_ptr->pcal_units = (png_charp)png_malloc_warn(png_ptr, length);
    if (info_ptr->pcal_units == NULL)
    {
-      png_warning(png_ptr, "Insufficient memory for pCAL units");
+       png_warning(png_ptr, "Insufficient memory for pCAL units");
       return;
    }
    png_memcpy(info_ptr->pcal_units, units, length);
 
    info_ptr->pcal_params = (png_charpp)png_malloc_warn(png_ptr,
-      (png_size_t)((nparams + 1) * sizeof(png_charp)));
+      (png_size_t)((nparams + 1) * png_sizeof(png_charp)));
    if (info_ptr->pcal_params == NULL)
    {
-      png_warning(png_ptr, "Insufficient memory for pCAL params");
+       png_warning(png_ptr, "Insufficient memory for pCAL params");
       return;
    }
 
@@ -435,12 +436,12 @@
    {
       length = png_strlen(params[i]) + 1;
       png_debug2(3, "allocating parameter %d for info (%lu bytes)\n", i,
-        (unsigned long) length);
+        (unsigned long)length);
       info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
       if (info_ptr->pcal_params[i] == NULL)
       {
-         png_warning(png_ptr, "Insufficient memory for pCAL parameter");
-         return;
+          png_warning(png_ptr, "Insufficient memory for pCAL parameter");
+          return;
       }
       png_memcpy(info_ptr->pcal_params[i], params[i], length);
    }
@@ -488,7 +489,9 @@
    info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, length);
    if (info_ptr->scal_s_width == NULL)
    {
-      png_warning(png_ptr, "Memory allocation failed while processing sCAL");
+      png_warning(png_ptr,
+       "Memory allocation failed while processing sCAL");
+      return;
    }
    png_memcpy(info_ptr->scal_s_width, swidth, length);
 
@@ -499,10 +502,11 @@
    if (info_ptr->scal_s_height == NULL)
    {
       png_free (png_ptr, info_ptr->scal_s_width);
-      png_warning(png_ptr, "Memory allocation failed while processing sCAL");
+      png_warning(png_ptr,
+       "Memory allocation failed while processing sCAL");
+      return;
    }
    png_memcpy(info_ptr->scal_s_height, sheight, length);
-
    info_ptr->valid |= PNG_INFO_sCAL;
 #ifdef PNG_FREE_ME_SUPPORTED
    info_ptr->free_me |= PNG_FREE_SCAL;
@@ -561,10 +565,10 @@
       of num_palette entries,
       in case of an invalid PNG file that has too-large sample values. */
    png_ptr->palette = (png_colorp)png_malloc(png_ptr,
-      PNG_MAX_PALETTE_LENGTH * sizeof(png_color));
+      PNG_MAX_PALETTE_LENGTH * png_sizeof(png_color));
    png_memset(png_ptr->palette, 0, PNG_MAX_PALETTE_LENGTH *
-      sizeof(png_color));
-   png_memcpy(png_ptr->palette, palette, num_palette * sizeof(png_color));
+      png_sizeof(png_color));
+   png_memcpy(png_ptr->palette, palette, num_palette * png_sizeof(png_color));
    info_ptr->palette = png_ptr->palette;
    info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
 
@@ -586,7 +590,7 @@
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   png_memcpy(&(info_ptr->sig_bit), sig_bit, sizeof(png_color_8));
+   png_memcpy(&(info_ptr->sig_bit), sig_bit, png_sizeof(png_color_8));
    info_ptr->valid |= PNG_INFO_sBIT;
 }
 #endif
@@ -682,23 +686,26 @@
 {
    png_charp new_iccp_name;
    png_charp new_iccp_profile;
+   png_uint_32 length;
 
    png_debug1(1, "in %s storage function\n", "iCCP");
    if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
       return;
 
-   new_iccp_name = (png_charp)png_malloc_warn(png_ptr, png_strlen(name)+1);
+   length = png_strlen(name)+1;
+   new_iccp_name = (png_charp)png_malloc_warn(png_ptr, length);
    if (new_iccp_name == NULL)
    {
       png_warning(png_ptr, "Insufficient memory to process iCCP chunk");
       return;
    }
-   png_strcpy(new_iccp_name, name);
+   png_memcpy(new_iccp_name, name, length);
    new_iccp_profile = (png_charp)png_malloc_warn(png_ptr, proflen);
    if (new_iccp_profile == NULL)
    {
       png_free (png_ptr, new_iccp_name);
-      png_warning(png_ptr, "Insufficient memory to process iCCP profile");
+      png_warning(png_ptr,
+      "Insufficient memory to process iCCP profile");
       return;
    }
    png_memcpy(new_iccp_profile, profile, (png_size_t)proflen);
@@ -755,14 +762,14 @@
          info_ptr->max_text = info_ptr->num_text + num_text + 8;
          old_text = info_ptr->text;
          info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
-            (png_size_t)(info_ptr->max_text * sizeof(png_text)));
+            (png_size_t)(info_ptr->max_text * png_sizeof(png_text)));
          if (info_ptr->text == NULL)
            {
              png_free(png_ptr, old_text);
              return(1);
            }
          png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
-            sizeof(png_text)));
+            png_sizeof(png_text)));
          png_free(png_ptr, old_text);
       }
       else
@@ -770,7 +777,7 @@
          info_ptr->max_text = num_text + 8;
          info_ptr->num_text = 0;
          info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
-            (png_uint_32)(info_ptr->max_text * sizeof(png_text)));
+            (png_size_t)(info_ptr->max_text * png_sizeof(png_text)));
          if (info_ptr->text == NULL)
            return(1);
 #ifdef PNG_FREE_ME_SUPPORTED
@@ -782,8 +789,8 @@
    }
    for (i = 0; i < num_text; i++)
    {
-      png_size_t text_length,key_len;
-      png_size_t lang_len,lang_key_len;
+      png_size_t text_length, key_len;
+      png_size_t lang_len, lang_key_len;
       png_textp textp = &(info_ptr->text[info_ptr->num_text]);
 
       if (text_ptr[i].key == NULL)
@@ -791,7 +798,7 @@
 
       key_len = png_strlen(text_ptr[i].key);
 
-      if(text_ptr[i].compression <= 0)
+      if (text_ptr[i].compression <= 0)
       {
         lang_len = 0;
         lang_key_len = 0;
@@ -820,7 +827,7 @@
       {
          text_length = 0;
 #ifdef PNG_iTXt_SUPPORTED
-         if(text_ptr[i].compression > 0)
+         if (text_ptr[i].compression > 0)
             textp->compression = PNG_ITXT_COMPRESSION_NONE;
          else
 #endif
@@ -833,26 +840,27 @@
       }
 
       textp->key = (png_charp)png_malloc_warn(png_ptr,
-         (png_size_t)(key_len + text_length + lang_len + lang_key_len + 4));
+         (png_size_t)
+         (key_len + text_length + lang_len + lang_key_len + 4));
       if (textp->key == NULL)
         return(1);
       png_debug2(2, "Allocated %lu bytes at %x in png_set_text\n",
-         (unsigned long)(png_uint_32)(key_len + lang_len + lang_key_len
-         + text_length + 4),
+         (unsigned long)(png_uint_32)
+         (key_len + lang_len + lang_key_len + text_length + 4),
          (int)textp->key);
 
       png_memcpy(textp->key, text_ptr[i].key,
          (png_size_t)(key_len));
-      *(textp->key+key_len) = '\0';
+      *(textp->key + key_len) = '\0';
 #ifdef PNG_iTXt_SUPPORTED
       if (text_ptr[i].compression > 0)
       {
          textp->lang=textp->key + key_len + 1;
          png_memcpy(textp->lang, text_ptr[i].lang, lang_len);
-         *(textp->lang+lang_len) = '\0';
+         *(textp->lang + lang_len) = '\0';
          textp->lang_key=textp->lang + lang_len + 1;
          png_memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
-         *(textp->lang_key+lang_key_len) = '\0';
+         *(textp->lang_key + lang_key_len) = '\0';
          textp->text=textp->lang_key + lang_key_len + 1;
       }
       else
@@ -864,13 +872,13 @@
 #endif
          textp->text=textp->key + key_len + 1;
       }
-      if(text_length)
+      if (text_length)
          png_memcpy(textp->text, text_ptr[i].text,
             (png_size_t)(text_length));
-      *(textp->text+text_length) = '\0';
+      *(textp->text + text_length) = '\0';
 
 #ifdef PNG_iTXt_SUPPORTED
-      if(textp->compression > 0)
+      if (textp->compression > 0)
       {
          textp->text_length = 0;
          textp->itxt_length = text_length;
@@ -899,7 +907,7 @@
        (png_ptr->mode & PNG_WROTE_tIME))
       return;
 
-   png_memcpy(&(info_ptr->mod_time), mod_time, sizeof(png_time));
+   png_memcpy(&(info_ptr->mod_time), mod_time, png_sizeof(png_time));
    info_ptr->valid |= PNG_INFO_tIME;
 }
 #endif
@@ -920,30 +928,45 @@
         * we do it for backward compatibility with the way the png_handle_tRNS
         * function used to do the allocation.
         */
+
 #ifdef PNG_FREE_ME_SUPPORTED
        png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
 #endif
+
        /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
        png_ptr->trans = info_ptr->trans = (png_bytep)png_malloc(png_ptr,
-           PNG_MAX_PALETTE_LENGTH);
-       if (num_trans <= PNG_MAX_PALETTE_LENGTH)
+           (png_size_t)PNG_MAX_PALETTE_LENGTH);
+       if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
          png_memcpy(info_ptr->trans, trans, (png_size_t)num_trans);
-#ifdef PNG_FREE_ME_SUPPORTED
-       info_ptr->free_me |= PNG_FREE_TRNS;
-#else
-       png_ptr->flags |= PNG_FLAG_FREE_TRNS;
-#endif
    }
 
    if (trans_values != NULL)
    {
+      int sample_max = (1 << info_ptr->bit_depth);
+      if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
+          (int)trans_values->gray > sample_max) ||
+          (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
+          ((int)trans_values->red > sample_max ||
+          (int)trans_values->green > sample_max ||
+          (int)trans_values->blue > sample_max)))
+        png_warning(png_ptr,
+           "tRNS chunk has out-of-range samples for bit_depth");
       png_memcpy(&(info_ptr->trans_values), trans_values,
-         sizeof(png_color_16));
+         png_sizeof(png_color_16));
       if (num_trans == 0)
         num_trans = 1;
    }
+
    info_ptr->num_trans = (png_uint_16)num_trans;
-   info_ptr->valid |= PNG_INFO_tRNS;
+   if (num_trans != 0)
+   {
+      info_ptr->valid |= PNG_INFO_tRNS;
+#ifdef PNG_FREE_ME_SUPPORTED
+      info_ptr->free_me |= PNG_FREE_TRNS;
+#else
+      png_ptr->flags |= PNG_FLAG_FREE_TRNS;
+#endif
+   }
 }
 #endif
 
@@ -966,7 +989,8 @@
        return;
 
     np = (png_sPLT_tp)png_malloc_warn(png_ptr,
-        (info_ptr->splt_palettes_num + nentries) * sizeof(png_sPLT_t));
+        (info_ptr->splt_palettes_num + nentries) *
+        (png_size_t)png_sizeof(png_sPLT_t));
     if (np == NULL)
     {
       png_warning(png_ptr, "No memory for sPLT palettes");
@@ -974,7 +998,7 @@
     }
 
     png_memcpy(np, info_ptr->splt_palettes,
-           info_ptr->splt_palettes_num * sizeof(png_sPLT_t));
+           info_ptr->splt_palettes_num * png_sizeof(png_sPLT_t));
     png_free(png_ptr, info_ptr->splt_palettes);
     info_ptr->splt_palettes=NULL;
 
@@ -982,15 +1006,29 @@
     {
         png_sPLT_tp to = np + info_ptr->splt_palettes_num + i;
         png_sPLT_tp from = entries + i;
+        png_uint_32 length;
 
-        to->name = (png_charp)png_malloc(png_ptr, png_strlen(from->name) + 1);
-        /* TODO: use png_malloc_warn */
-        png_strcpy(to->name, from->name);
-        to->entries = (png_sPLT_entryp)png_malloc(png_ptr,
-            from->nentries * sizeof(png_sPLT_entry));
-        /* TODO: use png_malloc_warn */
+        length = png_strlen(from->name) + 1;
+        to->name = (png_charp)png_malloc_warn(png_ptr, (png_size_t)length);
+        if (to->name == NULL)
+        {
+           png_warning(png_ptr,
+             "Out of memory while processing sPLT chunk");
+           continue;
+        }
+        png_memcpy(to->name, from->name, length);
+        to->entries = (png_sPLT_entryp)png_malloc_warn(png_ptr,
+            (png_size_t)(from->nentries * png_sizeof(png_sPLT_entry)));
+        if (to->entries == NULL)
+        {
+           png_warning(png_ptr,
+             "Out of memory while processing sPLT chunk");
+           png_free(png_ptr, to->name);
+           to->name = NULL;
+           continue;
+        }
         png_memcpy(to->entries, from->entries,
-            from->nentries * sizeof(png_sPLT_entry));
+            from->nentries * png_sizeof(png_sPLT_entry));
         to->nentries = from->nentries;
         to->depth = from->depth;
     }
@@ -1016,38 +1054,48 @@
         return;
 
     np = (png_unknown_chunkp)png_malloc_warn(png_ptr,
-        (info_ptr->unknown_chunks_num + num_unknowns) *
-        sizeof(png_unknown_chunk));
+        (png_size_t)((info_ptr->unknown_chunks_num + num_unknowns) *
+        png_sizeof(png_unknown_chunk)));
     if (np == NULL)
     {
-       png_warning(png_ptr, "Out of memory while processing unknown chunk");
+       png_warning(png_ptr,
+          "Out of memory while processing unknown chunk");
        return;
     }
 
     png_memcpy(np, info_ptr->unknown_chunks,
-           info_ptr->unknown_chunks_num * sizeof(png_unknown_chunk));
+           info_ptr->unknown_chunks_num * png_sizeof(png_unknown_chunk));
     png_free(png_ptr, info_ptr->unknown_chunks);
     info_ptr->unknown_chunks=NULL;
 
     for (i = 0; i < num_unknowns; i++)
     {
-        png_unknown_chunkp to = np + info_ptr->unknown_chunks_num + i;
-        png_unknown_chunkp from = unknowns + i;
+       png_unknown_chunkp to = np + info_ptr->unknown_chunks_num + i;
+       png_unknown_chunkp from = unknowns + i;
 
-        png_strncpy((png_charp)to->name, (png_charp)from->name, 5);
-        to->data = (png_bytep)png_malloc_warn(png_ptr, from->size);
-        if (to->data == NULL)
-        {
-           png_warning(png_ptr, "Out of memory processing unknown chunk");
-        }
-        else
-        {
-           png_memcpy(to->data, from->data, from->size);
-           to->size = from->size;
+       png_memcpy((png_charp)to->name, 
+                  (png_charp)from->name, 
+                  png_sizeof(from->name));
+       to->name[png_sizeof(to->name)-1] = '\0';
+       to->size = from->size;
+       /* note our location in the read or write sequence */
+       to->location = (png_byte)(png_ptr->mode & 0xff);
 
-           /* note our location in the read or write sequence */
-           to->location = (png_byte)(png_ptr->mode & 0xff);
-        }
+       if (from->size == 0)
+          to->data=NULL;
+       else
+       {
+          to->data = (png_bytep)png_malloc_warn(png_ptr,
+            (png_size_t)from->size);
+          if (to->data == NULL)
+          {
+             png_warning(png_ptr,
+              "Out of memory while processing unknown chunk");
+             to->size = 0;
+          }
+          else
+             png_memcpy(to->data, from->data, from->size);
+       }
     }
 
     info_ptr->unknown_chunks = np;
@@ -1060,12 +1108,13 @@
 png_set_unknown_chunk_location(png_structp png_ptr, png_infop info_ptr,
    int chunk, int location)
 {
-   if(png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk <
+   if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk <
          (int)info_ptr->unknown_chunks_num)
       info_ptr->unknown_chunks[chunk].location = (png_byte)location;
 }
 #endif
 
+
 #if defined(PNG_MNG_FEATURES_SUPPORTED)
 png_uint_32 PNGAPI
 png_permit_mng_features (png_structp png_ptr, png_uint_32 mng_features)
@@ -1090,12 +1139,12 @@
        return;
     if (num_chunks == 0)
     {
-      if(keep == PNG_HANDLE_CHUNK_ALWAYS || keep == PNG_HANDLE_CHUNK_IF_SAFE)
+      if (keep == PNG_HANDLE_CHUNK_ALWAYS || keep == PNG_HANDLE_CHUNK_IF_SAFE)
         png_ptr->flags |= PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
       else
         png_ptr->flags &= ~PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
 
-      if(keep == PNG_HANDLE_CHUNK_ALWAYS)
+      if (keep == PNG_HANDLE_CHUNK_ALWAYS)
         png_ptr->flags |= PNG_FLAG_KEEP_UNSAFE_CHUNKS;
       else
         png_ptr->flags &= ~PNG_FLAG_KEEP_UNSAFE_CHUNKS;
@@ -1105,19 +1154,20 @@
       return;
     old_num_chunks=png_ptr->num_chunk_list;
     new_list=(png_bytep)png_malloc(png_ptr,
-       (png_size_t)(5*(num_chunks+old_num_chunks)));
-    if(png_ptr->chunk_list != NULL)
+       (png_size_t)
+       (5*(num_chunks + old_num_chunks)));
+    if (png_ptr->chunk_list != NULL)
     {
        png_memcpy(new_list, png_ptr->chunk_list,
           (png_size_t)(5*old_num_chunks));
        png_free(png_ptr, png_ptr->chunk_list);
        png_ptr->chunk_list=NULL;
     }
-    png_memcpy(new_list+5*old_num_chunks, chunk_list,
+    png_memcpy(new_list + 5*old_num_chunks, chunk_list,
        (png_size_t)(5*num_chunks));
-    for (p=new_list+5*old_num_chunks+4, i=0; i<num_chunks; i++, p+=5)
+    for (p=new_list + 5*old_num_chunks + 4, i = 0; i<num_chunks; i++, p += 5)
        *p=(png_byte)keep;
-    png_ptr->num_chunk_list=old_num_chunks+num_chunks;
+    png_ptr->num_chunk_list=old_num_chunks + num_chunks;
     png_ptr->chunk_list=new_list;
 #ifdef PNG_FREE_ME_SUPPORTED
     png_ptr->free_me |= PNG_FREE_LIST;
@@ -1147,22 +1197,22 @@
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   if(info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
+   if (info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
       png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
    info_ptr->row_pointers = row_pointers;
-   if(row_pointers)
+   if (row_pointers)
       info_ptr->valid |= PNG_INFO_IDAT;
 }
 #endif
 
 #ifdef PNG_WRITE_SUPPORTED
 void PNGAPI
-png_set_compression_buffer_size(png_structp png_ptr, png_size_t size)
+png_set_compression_buffer_size(png_structp png_ptr,
+    png_size_t size)
 {
     if (png_ptr == NULL)
        return;
-    if(png_ptr->zbuf)
-       png_free(png_ptr, png_ptr->zbuf);
+    png_free(png_ptr, png_ptr->zbuf);
     png_ptr->zbuf_size = size;
     png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, size);
     png_ptr->zstream.next_out = png_ptr->zbuf;
@@ -1174,73 +1224,10 @@
 png_set_invalid(png_structp png_ptr, png_infop info_ptr, int mask)
 {
    if (png_ptr && info_ptr)
-      info_ptr->valid &= ~(mask);
+      info_ptr->valid &= ~mask;
 }
 
 
-#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
-/* this function was added to libpng 1.2.0 and should always exist by default */
-void PNGAPI
-png_set_asm_flags (png_structp png_ptr, png_uint_32 asm_flags)
-{
-    png_uint_32 settable_asm_flags;
-    png_uint_32 settable_mmx_flags;
-
-    if (png_ptr == NULL)
-       return;
-
-    settable_mmx_flags =
-#ifdef PNG_MMX_CODE_SUPPORTED
-#ifdef PNG_HAVE_MMX_COMBINE_ROW
-                         PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  |
-#endif
-#ifdef PNG_HAVE_MMX_READ_INTERLACE
-                         PNG_ASM_FLAG_MMX_READ_INTERLACE    |
-#endif
-#ifdef PNG_HAVE_MMX_READ_FILTER_ROW
-                         PNG_ASM_FLAG_MMX_READ_FILTER_SUB   |
-                         PNG_ASM_FLAG_MMX_READ_FILTER_UP    |
-                         PNG_ASM_FLAG_MMX_READ_FILTER_AVG   |
-                         PNG_ASM_FLAG_MMX_READ_FILTER_PAETH |
-#endif
-#endif
-                         0;
-
-    /* could be some non-MMX ones in the future, but not currently: */
-    settable_asm_flags = settable_mmx_flags;
-
-#ifdef PNG_MMX_CODE_SUPPORTED
-    if (!(png_ptr->asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_COMPILED) ||
-        !(png_ptr->asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU))
-    {
-        /* clear all MMX flags if MMX isn't supported */
-        settable_asm_flags &= ~settable_mmx_flags;
-        png_ptr->asm_flags &= ~settable_mmx_flags;
-    }
-#endif
-
-    /* we're replacing the settable bits with those passed in by the user,
-     * so first zero them out of the master copy, then bitwise-OR in the
-     * allowed subset that was requested */
-
-    png_ptr->asm_flags &= ~settable_asm_flags;               /* zero them */
-    png_ptr->asm_flags |= (asm_flags & settable_asm_flags);  /* set them */
-}
-#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
-
-#ifdef PNG_MMX_CODE_SUPPORTED
-/* this function was added to libpng 1.2.0 */
-void PNGAPI
-png_set_mmx_thresholds (png_structp png_ptr,
-                        png_byte mmx_bitdepth_threshold,
-                        png_uint_32 mmx_rowbytes_threshold)
-{
-    if (png_ptr == NULL)
-       return;
-    png_ptr->mmx_bitdepth_threshold = mmx_bitdepth_threshold;
-    png_ptr->mmx_rowbytes_threshold = mmx_rowbytes_threshold;
-}
-#endif /* ?PNG_MMX_CODE_SUPPORTED */
 
 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
 /* this function was added to libpng 1.2.6 */
@@ -1252,7 +1239,7 @@
      * rejected by png_set_IHDR().  To accept any PNG datastream
      * regardless of dimensions, set both limits to 0x7ffffffL.
      */
-    if(png_ptr == NULL) return;
+    if (png_ptr == NULL) return;
     png_ptr->user_width_max = user_width_max;
     png_ptr->user_height_max = user_height_max;
 }
@@ -1270,5 +1257,4 @@
      png_ptr->flags &= ~PNG_FLAG_BENIGN_ERRORS_WARN;
 }
 #endif /* PNG_BENIGN_ERRORS_SUPPORTED */
-
 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */