Function LoadCloudFile

Telegram/SourceFiles/data/data_cloud_file.cpp:233–307

}

void LoadCloudFile(
		not_null<Main::Session*> session,
		CloudFile &file,
		FileOrigin origin,
		LoadFromCloudSetting fromCloud,
		bool autoLoading,
		uint8 cacheTag,
		Fn<bool()> finalCheck,
		Fn<void(CloudFile&)> done,
		Fn<void(bool)> fail,
		Fn<void()> progress,
		int downloadFrontPartSize = 0) {
	const auto loadSize = downloadFrontPartSize
		? std::min(downloadFrontPartSize, file.byteSize)
		: file.byteSize;
	if (file.loader) {
		if (fromCloud == LoadFromCloudOrLocal) {
			file.loader->permitLoadFromCloud();
		}
		if (file.loader->loadSize() < loadSize) {
			file.loader->increaseLoadSize(loadSize, autoLoading);
		}
		return;
	} else if ((file.flags & CloudFile::Flag::Failed)
		|| !file.location.valid()
		|| (finalCheck && !finalCheck())) {
		return;
	}
	file.flags &= ~CloudFile::Flag::Cancelled;
	file.loader = CreateFileLoader(
		session,
		file.location.file(),
		origin,
		QString(),
		loadSize,
		file.byteSize,
		UnknownFileLocation,
		LoadToCacheAsWell,
		fromCloud,
		autoLoading,
		cacheTag);

	const auto finish = [done](CloudFile &file) {
		if (!file.loader || file.loader->cancelled()) {
			file.flags |= CloudFile::Flag::Cancelled;
		} else {
			file.flags |= CloudFile::Flag::Loaded;
			done(file);
		}
		// NB! file.loader may be in ~FileLoader() already.
		if (const auto loader = base::take(file.loader)) {
			if ((file.flags & CloudFile::Flag::Cancelled)
				&& !loader->cancelled()) {
				loader->cancel();
			}
		}
	};