Function DetermineOldSavegameTypeAndName

src/saveload/oldloader.cpp:213–230

}

static std::tuple<SavegameType, std::string> DetermineOldSavegameTypeAndName(FileHandle &f)
{
	long pos = ftell(f);
	char buffer[std::max(TTO_HEADER_SIZE, TTD_HEADER_SIZE)];
	if (pos < 0 || fread(buffer, 1, lengthof(buffer), f) != lengthof(buffer)) {
		return { SGT_INVALID, "(broken) Unable to read file" };
	}

	if (VerifyOldNameChecksum(buffer, TTO_HEADER_SIZE) && fseek(f, pos + TTO_HEADER_SIZE, SEEK_SET) == 0) {
		return { SGT_TTO, "(TTO) " + StrMakeValid(std::string_view{buffer, TTO_HEADER_SIZE - HEADER_CHECKSUM_SIZE}) };
	}

	if (VerifyOldNameChecksum(buffer, TTD_HEADER_SIZE) && fseek(f, pos + TTD_HEADER_SIZE, SEEK_SET) == 0) {
		return { SGT_TTD, "(TTD) " + StrMakeValid(std::string_view{buffer, TTD_HEADER_SIZE - HEADER_CHECKSUM_SIZE}) };
	}

	return { SGT_INVALID, "(broken) Unknown" };
}

typedef bool LoadOldMainProc(LoadgameState &ls);