Update to libpng 1.2.52 (rollup change only)

third_party/libpng/pngrtran.c

 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * Last changed in libpng 1.2.45 [July 7, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.2.51 [February 6, 2014]
+ * Copyright (c) 1998-2014 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 functions optionally called by an application
  * in order to tell libpng how to handle data when reading a PNG.
  * Transformations that are used in both reading and writing are
@@ skipping 894 matching lines @@
 
    if ((color_type == PNG_COLOR_TYPE_PALETTE && png_ptr->num_trans != 0)
        && (fabs(png_ptr->screen_gamma * png_ptr->gamma - 1.0)
          < PNG_GAMMA_THRESHOLD))
    {
     int i, k;
     k=0;
     for (i=0; i<png_ptr->num_trans; i++)
     {
       if (png_ptr->trans[i] != 0 && png_ptr->trans[i] != 0xff)
+      {
         k=1; /* Partial transparency is present */
+        break;
+      }
     }
     if (k == 0)
       png_ptr->transformations &= ~PNG_GAMMA;
    }
 
    if ((png_ptr->transformations & (PNG_GAMMA | PNG_RGB_TO_GRAY)) &&
         png_ptr->gamma != 0.0)
    {
       png_build_gamma_table(png_ptr);
 
@@ skipping 225 matching lines @@
       }
 
       /* Handled alpha, still need to strip the channel. */
       png_ptr->transformations &= ~PNG_BACKGROUND;
       png_ptr->transformations |= PNG_STRIP_ALPHA;
    }
 #endif /* PNG_READ_BACKGROUND_SUPPORTED */
 
 #ifdef PNG_READ_SHIFT_SUPPORTED
    if ((png_ptr->transformations & PNG_SHIFT) &&
+      !(png_ptr->transformations & PNG_EXPAND) &&
       (color_type == PNG_COLOR_TYPE_PALETTE))
    {
       png_uint_16 i;
       png_uint_16 istop = png_ptr->num_palette;
       int sr = 8 - png_ptr->sig_bit.red;
       int sg = 8 - png_ptr->sig_bit.green;
       int sb = 8 - png_ptr->sig_bit.blue;
 
       if (sr < 0 || sr > 8)
          sr = 0;
       if (sg < 0 || sg > 8)
          sg = 0;
       if (sb < 0 || sb > 8)
          sb = 0;
       for (i = 0; i < istop; i++)
       {
          png_ptr->palette[i].red >>= sr;
          png_ptr->palette[i].green >>= sg;
          png_ptr->palette[i].blue >>= sb;
       }
+
+      png_ptr->transformations &= ~PNG_SHIFT;
    }
 #endif  /* PNG_READ_SHIFT_SUPPORTED */
  }
 #if !defined(PNG_READ_GAMMA_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) \
  && !defined(PNG_READ_BACKGROUND_SUPPORTED)
    if (png_ptr)
       return;
 #endif
 }
 
@@ skipping 170 matching lines @@
 #else
       png_warning(png_ptr, "Uninitialized row");
 #endif
 #endif
 
 #ifdef PNG_READ_EXPAND_SUPPORTED
    if (png_ptr->transformations & PNG_EXPAND)
    {
       if (png_ptr->row_info.color_type == PNG_COLOR_TYPE_PALETTE)
       {
+         if (png_ptr->palette == NULL)
+            png_error (png_ptr, "Palette is NULL in indexed image");
+
          png_do_expand_palette(&(png_ptr->row_info), png_ptr->row_buf + 1,
             png_ptr->palette, png_ptr->trans, png_ptr->num_trans);
       }
       else
       {
          if (png_ptr->num_trans &&
              (png_ptr->transformations & PNG_EXPAND_tRNS))
             png_do_expand(&(png_ptr->row_info), png_ptr->row_buf + 1,
                &(png_ptr->trans_values));
          else
@@ skipping 3072 matching lines @@
             *(rp  ) = (png_byte)((red >> 8) & 0xff);
             *(rp+1) = (png_byte)(red & 0xff);
             *(rp+4) = (png_byte)((blue >> 8) & 0xff);
             *(rp+5) = (png_byte)(blue & 0xff);
          }
       }
    }
 }
 #endif /* PNG_MNG_FEATURES_SUPPORTED */
 #endif /* PNG_READ_SUPPORTED */