Update to libpng 1.2.52 (rollup change only)

third_party/libpng/pngwrite.c

 
 /* pngwrite.c - general routines to write a PNG file
  *
- * Last changed in libpng 1.2.45 [July 7, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng 1.2.52 [November 20, 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
  */
 
 /* Get internal access to png.h */
 #define PNG_INTERNAL
@@ skipping 502 matching lines @@
 #ifdef USE_FAR_KEYWORD
    png_memcpy(png_ptr->jmpbuf, jmpbuf, png_sizeof(jmp_buf));
 #endif
 #endif
 
 #ifdef PNG_USER_MEM_SUPPORTED
    png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
 #endif /* PNG_USER_MEM_SUPPORTED */
    png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
 
-   if (user_png_ver)
+   if (user_png_ver != NULL)
    {
-      i = 0;
+      int found_dots = 0;
+      i = -1;
+
       do
       {
-         if (user_png_ver[i] != png_libpng_ver[i])
+         i++;
+         if (user_png_ver[i] != PNG_LIBPNG_VER_STRING[i])
             png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
-      } while (png_libpng_ver[i++]);
+         if (user_png_ver[i] == '.')
+            found_dots++;
+      } while (found_dots < 2 && user_png_ver[i] != 0 &&
+            PNG_LIBPNG_VER_STRING[i] != 0);
    }
+   else
+      png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
 
    if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
    {
      /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
       * we must recompile any applications that use any older library version.
       * For versions after libpng 1.0, we will be compatible, so we need
       * only check the first digit.
       */
      if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
          (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
@@ skipping 130 matching lines @@
    {
       if (user_png_ver[i] != png_libpng_ver[i])
       {
 #ifdef PNG_LEGACY_SUPPORTED
          png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
 #else
          png_ptr->warning_fn = NULL;
          png_warning(png_ptr,
  "Application uses deprecated png_write_init() and should be recompiled.");
 #endif
-      }
-   } while (png_libpng_ver[i++]);
+   }
+      i++;
+   } while (png_libpng_ver[i] != 0 && user_png_ver[i] != 0);
 
    png_debug(1, "in png_write_init_3");
 
 #ifdef PNG_SETJMP_SUPPORTED
    /* Save jump buffer and error functions */
    png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf));
 #endif
 
    if (png_sizeof(png_struct) > png_struct_size)
    {
@@ skipping 880 matching lines @@
 
    /* ----------------------- end of transformations ------------------- */
 
    /* Write the bits */
    if (info_ptr->valid & PNG_INFO_IDAT)
        png_write_image(png_ptr, info_ptr->row_pointers);
 
    /* It is REQUIRED to call this to finish writing the rest of the file */
    png_write_end(png_ptr, info_ptr);
 
-   transforms = transforms; /* Quiet compiler warnings */
-   params = params;
+   PNG_UNUSED(transforms) /* Quiet compiler warnings */
+   PNG_UNUSED(params)
 }
 #endif
 #endif /* PNG_WRITE_SUPPORTED */