Function stbi__malloc_mad2

include/stb/stb_image.h:1048–1052

mallocs with size overflow checking

#if !defined(STBI_NO_JPEG) || !defined(STBI_NO_PNG) || !defined(STBI_NO_TGA) || !defined(STBI_NO_HDR)
// mallocs with size overflow checking
static void *stbi__malloc_mad2(int a, int b, int add)
{
   if (!stbi__mad2sizes_valid(a, b, add)) return NULL;
   return stbi__malloc(a*b + add);
}
#endif

static void *stbi__malloc_mad3(int a, int b, int c, int add)