rem: bool DetermineType(BPositionIO *source, bool *is_gif) {
add: DetermineType(BPositionIO *source, bool *is_gif) {
context: bool DetermineType(BPositionIO *source, bool *is_gif) {	unsigned char header[7];	*is_gif = true;	if (source->Read(header, 6) != 6) return false;	header[6] = 0x00;		if (strcmp((char *)header, "GIF87a") != 0 && strcmp((char *)header, "GIF89a") != 0) {		*is_gif = false;		int32 magic = (header[0] << 24) + (header[1] << 16) + (header[2] << 8) + header[3];		if (magic != B_TRANSLATOR_BITMAP) return false;		source->Seek(5 * 4 - 2, SEEK_CUR);		color_space cs;		if (source->Read(&cs, 4) != 4) return false;		cs = (color_space)B_BENDIAN_TO_HOST_INT32(cs);		if (cs != B_RGB32 && cs != B_RGBA32 && cs != B_RGB32_BIG && cs != B_RGBA32_BIG) return false;	}		source->Seek(0, SEEK_SET);	return true;}