#492 memory leak in WriteHISTOGRAMImage

[bestshow]

Here is the critical code : (in WriteHISTOGRAMImage)

  length=Max(ScaleQuantumToChar(MaxRGB)+1,histogram_image->columns);
  red=MagickAllocateMemory(long *,length*sizeof(long)); //225
  green=MagickAllocateMemory(long *,length*sizeof(long));
  blue=MagickAllocateMemory(long *,length*sizeof(long));
  if ((red == (long *) NULL) || (green == (long *) NULL) ||
      (blue == (long *) NULL))
    {
      DestroyImage(histogram_image);
      ThrowWriterException(ResourceLimitError,MemoryAllocationFailed,image)
    }

If one of the “red”,”green” and ”blue” is NULL at least，and others are not，this may cause memory leak
Credit : ADLab of Venustech

[Bob Friesenhahn]

This problem is fixed by Mercurial changeset 15198:9e6afa7ba7b9. Thanks for the report!