Function GetSavegameFormat

src/saveload/saveload.cpp:2849–2889

* Return the savegameformat of the game. Whether it was created with ZLIB compression * uncompressed, or another type * @param full_name Name of the savegame format. If empty it picks the first available one * @return Pair containing reference to SaveLoadFormat struct giving all characteristics of this type of savegame, and a compression level to use. */

 * @return Pair containing reference to SaveLoadFormat struct giving all characteristics of this type of savegame, and a compression level to use.
 */
static std::pair<const SaveLoadFormat &, uint8_t> GetSavegameFormat(std::string_view full_name)
{
	/* Find default savegame format, the highest one with which files can be written. */
	auto it = std::find_if(std::rbegin(_saveload_formats), std::rend(_saveload_formats), [](const auto &slf) { return slf.init_write != nullptr; });
	if (it == std::rend(_saveload_formats)) SlError(STR_GAME_SAVELOAD_ERROR_BROKEN_INTERNAL_ERROR, "no writeable savegame formats");

	const SaveLoadFormat &def = *it;

	if (!full_name.empty()) {
		/* Get the ":..." of the compression level out of the way */
		size_t separator = full_name.find(':');
		bool has_comp_level = separator != std::string::npos;
		std::string_view name = has_comp_level ? full_name.substr(0, separator) : full_name;

		for (const auto &slf : _saveload_formats) {
			if (slf.init_write != nullptr && name == slf.name) {
				if (has_comp_level) {
					auto complevel = full_name.substr(separator + 1);

					/* Get the level and determine whether all went fine. */
					auto level = ParseInteger<uint8_t>(complevel);
					if (!level.has_value() || *level != Clamp(*level, slf.min_compression, slf.max_compression)) {
						ShowErrorMessage(
							GetEncodedString(STR_CONFIG_ERROR),
							GetEncodedString(STR_CONFIG_ERROR_INVALID_SAVEGAME_COMPRESSION_LEVEL, complevel),
							WL_CRITICAL);
					} else {
						return {slf, *level};
					}
				}
				return {slf, slf.default_compression};
			}
		}

		ShowErrorMessage(
			GetEncodedString(STR_CONFIG_ERROR),
			GetEncodedString(STR_CONFIG_ERROR_INVALID_SAVEGAME_COMPRESSION_ALGORITHM, name, def.name),
			WL_CRITICAL);
	}
	return {def, def.default_compression};
}

/* actual loader/saver function */
void InitializeGame(uint size_x, uint size_y, bool reset_date, bool reset_settings);