Updates the PNG library to 1.2.37, enables some functionality for O3D

third_party/libpng/pngread.c

Index: third_party/libpng/pngread.c
===================================================================
--- third_party/libpng/pngread.c	(revision 18910)
+++ third_party/libpng/pngread.c	(working copy)
@@ -1,7 +1,7 @@
 
 /* pngread.c - read a PNG file
  *
- * Last changed in libpng 1.2.35 [February 14, 2009]
+ * Last changed in libpng 1.2.37 [June 4, 2009]
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2009 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -57,7 +57,7 @@
    if (png_ptr == NULL)
       return (NULL);
 
-   /* added at libpng-1.2.6 */
+   /* Added at libpng-1.2.6 */
 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
    png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
    png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
@@ -137,7 +137,7 @@
      }
    }
 
-   /* initialize zbuf - compression buffer */
+   /* Initialize zbuf - compression buffer */
    png_ptr->zbuf_size = PNG_ZBUF_SIZE;
    png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
      (png_uint_32)png_ptr->zbuf_size);
@@ -192,7 +192,8 @@
    png_size_t png_struct_size, png_size_t png_info_size)
 {
    /* We only come here via pre-1.0.12-compiled applications */
-   if (png_ptr == NULL) return;
+   if (png_ptr == NULL)
+      return;
 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
    if (png_sizeof(png_struct) > png_struct_size ||
       png_sizeof(png_info) > png_info_size)
@@ -246,7 +247,8 @@
 
    png_structp png_ptr=*ptr_ptr;
 
-   if (png_ptr == NULL) return;
+   if (png_ptr == NULL)
+      return;
 
    do
    {
@@ -266,7 +268,7 @@
    png_debug(1, "in png_read_init_3");
 
 #ifdef PNG_SETJMP_SUPPORTED
-   /* save jump buffer and error functions */
+   /* Save jump buffer and error functions */
    png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf));
 #endif
 
@@ -277,21 +279,21 @@
       png_ptr = *ptr_ptr;
    }
 
-   /* reset all variables to 0 */
+   /* Reset all variables to 0 */
    png_memset(png_ptr, 0, png_sizeof(png_struct));
 
 #ifdef PNG_SETJMP_SUPPORTED
-   /* restore jump buffer */
+   /* Restore jump buffer */
    png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof(jmp_buf));
 #endif
 
-   /* added at libpng-1.2.6 */
+   /* Added at libpng-1.2.6 */
 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
    png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
    png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
 #endif
 
-   /* initialize zbuf - compression buffer */
+   /* Initialize zbuf - compression buffer */
    png_ptr->zbuf_size = PNG_ZBUF_SIZE;
    png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
      (png_uint_32)png_ptr->zbuf_size);
@@ -326,7 +328,8 @@
 void PNGAPI
 png_read_info(png_structp png_ptr, png_infop info_ptr)
 {
-   if (png_ptr == NULL || info_ptr == NULL) return;
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
    png_debug(1, "in png_read_info");
    /* If we haven't checked all of the PNG signature bytes, do so now. */
    if (png_ptr->sig_bytes < 8)
@@ -529,12 +532,13 @@
 }
 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
 
-/* optional call to update the users info_ptr structure */
+/* Optional call to update the users info_ptr structure */
 void PNGAPI
 png_read_update_info(png_structp png_ptr, png_infop info_ptr)
 {
    png_debug(1, "in png_read_update_info");
-   if (png_ptr == NULL) return;
+   if (png_ptr == NULL)
+      return;
    if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
       png_read_start_row(png_ptr);
    else
@@ -553,7 +557,8 @@
 png_start_read_image(png_structp png_ptr)
 {
    png_debug(1, "in png_start_read_image");
-   if (png_ptr == NULL) return;
+   if (png_ptr == NULL)
+      return;
    if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
       png_read_start_row(png_ptr);
 }
@@ -570,14 +575,15 @@
    PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
 #endif
    int ret;
-   if (png_ptr == NULL) return;
+   if (png_ptr == NULL)
+      return;
    png_debug2(1, "in png_read_row (row %lu, pass %d)",
       png_ptr->row_number, png_ptr->pass);
    if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
       png_read_start_row(png_ptr);
    if (png_ptr->row_number == 0 && png_ptr->pass == 0)
    {
-   /* check for transforms that have been set but were defined out */
+   /* Check for transforms that have been set but were defined out */
 #if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED)
    if (png_ptr->transformations & PNG_INVERT_MONO)
       png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined.");
@@ -609,7 +615,7 @@
    }
 
 #if defined(PNG_READ_INTERLACING_SUPPORTED)
-   /* if interlaced and we do not need a new row, combine row and return */
+   /* If interlaced and we do not need a new row, combine row and return */
    if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
    {
       switch (png_ptr->pass)
@@ -756,15 +762,15 @@
       png_do_read_transformations(png_ptr);
 
 #if defined(PNG_READ_INTERLACING_SUPPORTED)
-   /* blow up interlaced rows to full size */
+   /* Blow up interlaced rows to full size */
    if (png_ptr->interlaced &&
       (png_ptr->transformations & PNG_INTERLACE))
    {
       if (png_ptr->pass < 6)
-/*       old interface (pre-1.0.9):
-         png_do_read_interlace(&(png_ptr->row_info),
-            png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
- */
+         /* Old interface (pre-1.0.9):
+          * png_do_read_interlace(&(png_ptr->row_info),
+          *    png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
+          */
          png_do_read_interlace(png_ptr);
 
       if (dsp_row != NULL)
@@ -823,7 +829,8 @@
    png_bytepp dp;
 
    png_debug(1, "in png_read_rows");
-   if (png_ptr == NULL) return;
+   if (png_ptr == NULL)
+      return;
    rp = row;
    dp = display_row;
    if (rp != NULL && dp != NULL)
@@ -872,7 +879,8 @@
    png_bytepp rp;
 
    png_debug(1, "in png_read_image");
-   if (png_ptr == NULL) return;
+   if (png_ptr == NULL)
+      return;
 
 #ifdef PNG_READ_INTERLACING_SUPPORTED
    pass = png_set_interlace_handling(png_ptr);
@@ -908,7 +916,8 @@
 png_read_end(png_structp png_ptr, png_infop info_ptr)
 {
    png_debug(1, "in png_read_end");
-   if (png_ptr == NULL) return;
+   if (png_ptr == NULL)
+      return;
    png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
 
    do
@@ -1075,7 +1084,7 @@
 }
 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
 
-/* free all memory used by the read */
+/* Free all memory used by the read */
 void PNGAPI
 png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr,
    png_infopp end_info_ptr_ptr)
@@ -1147,7 +1156,7 @@
    }
 }
 
-/* free all memory used by the read (old method) */
+/* Free all memory used by the read (old method) */
 void /* PRIVATE */
 png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr)
 {
@@ -1296,7 +1305,8 @@
 void PNGAPI
 png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn)
 {
-   if (png_ptr == NULL) return;
+   if (png_ptr == NULL)
+      return;
    png_ptr->read_row_fn = read_row_fn;
 }
 
@@ -1310,9 +1320,10 @@
 {
    int row;
 
-   if (png_ptr == NULL) return;
+   if (png_ptr == NULL)
+      return;
 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
-   /* invert the alpha channel from opacity to transparency
+   /* Invert the alpha channel from opacity to transparency
     */
    if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
        png_set_invert_alpha(png_ptr);
@@ -1328,10 +1339,10 @@
    /* -------------- image transformations start here ------------------- */
 
 #if defined(PNG_READ_16_TO_8_SUPPORTED)
-   /* tell libpng to strip 16 bit/color files down to 8 bits per color
+   /* Tell libpng to strip 16 bit/color files down to 8 bits per color.
     */
    if (transforms & PNG_TRANSFORM_STRIP_16)
-       png_set_strip_16(png_ptr);
+      png_set_strip_16(png_ptr);
 #endif
 
 #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
@@ -1339,7 +1350,7 @@
     * the background (not recommended).
     */
    if (transforms & PNG_TRANSFORM_STRIP_ALPHA)
-       png_set_strip_alpha(png_ptr);
+      png_set_strip_alpha(png_ptr);
 #endif
 
 #if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED)
@@ -1347,7 +1358,7 @@
     * byte into separate bytes (useful for paletted and grayscale images).
     */
    if (transforms & PNG_TRANSFORM_PACKING)
-       png_set_packing(png_ptr);
+      png_set_packing(png_ptr);
 #endif
 
 #if defined(PNG_READ_PACKSWAP_SUPPORTED)
@@ -1355,7 +1366,7 @@
     * (not useful if you are using png_set_packing).
     */
    if (transforms & PNG_TRANSFORM_PACKSWAP)
-       png_set_packswap(png_ptr);
+      png_set_packswap(png_ptr);
 #endif
 
 #if defined(PNG_READ_EXPAND_SUPPORTED)
@@ -1365,9 +1376,9 @@
     * channels so the data will be available as RGBA quartets.
     */
    if (transforms & PNG_TRANSFORM_EXPAND)
-       if ((png_ptr->bit_depth < 8) ||
-           (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ||
-           (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
+      if ((png_ptr->bit_depth < 8) ||
+          (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ||
+          (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
          png_set_expand(png_ptr);
 #endif
 
@@ -1375,10 +1386,10 @@
     */
 
 #if defined(PNG_READ_INVERT_SUPPORTED)
-   /* invert monochrome files to have 0 as white and 1 as black
+   /* Invert monochrome files to have 0 as white and 1 as black
     */
    if (transforms & PNG_TRANSFORM_INVERT_MONO)
-       png_set_invert_mono(png_ptr);
+      png_set_invert_mono(png_ptr);
 #endif
 
 #if defined(PNG_READ_SHIFT_SUPPORTED)
@@ -1397,24 +1408,24 @@
 #endif
 
 #if defined(PNG_READ_BGR_SUPPORTED)
-   /* flip the RGB pixels to BGR (or RGBA to BGRA)
+   /* Flip the RGB pixels to BGR (or RGBA to BGRA)
     */
    if (transforms & PNG_TRANSFORM_BGR)
-       png_set_bgr(png_ptr);
+      png_set_bgr(png_ptr);
 #endif
 
 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
-   /* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR)
+   /* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR)
     */
    if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
        png_set_swap_alpha(png_ptr);
 #endif
 
 #if defined(PNG_READ_SWAP_SUPPORTED)
-   /* swap bytes of 16 bit files to least significant byte first
+   /* Swap bytes of 16 bit files to least significant byte first
     */
    if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
-       png_set_swap(png_ptr);
+      png_set_swap(png_ptr);
 #endif
 
    /* We don't handle adding filler bytes */
@@ -1447,10 +1458,10 @@
    png_read_image(png_ptr, info_ptr->row_pointers);
    info_ptr->valid |= PNG_INFO_IDAT;
 
-   /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
+   /* Read rest of file, and get additional chunks in info_ptr - REQUIRED */
    png_read_end(png_ptr, info_ptr);
 
-   transforms = transforms; /* quiet compiler warnings */
+   transforms = transforms; /* Quiet compiler warnings */
    params = params;
 
 }