static size_t consumer_put(void* info, const void* buffer, size_t count) {
SkWStream* stream = reinterpret_cast<SkWStream*>(info);
return stream->write(buffer, count) ? count : 0;
}
static void write_png_callback(png_structp png_ptr, png_bytep data, png_size_t length) {
SkWStream* out = (SkWStream*) png_get_io_ptr(png_ptr);
out->write(data, length);
}
static void sk_write_fn(png_structp png_ptr, png_bytep data, png_size_t len) {
SkWStream* stream = (SkWStream*)png_get_io_ptr(png_ptr);
if (!stream->write(data, len)) {
png_error(png_ptr, "sk_write_fn cannot write to stream");
}
}