public FileLocker(string fileToLock)
{
#if PLATFORM_WINDOWS
innerLocker = new WindowsFileLocker(fileToLock);
#else
innerLocker = new PosixFileLocker(fileToLock);
#endif
}
private bool TryFetchFromCacheOrUriInner(Uri uri, out string fileName)
{
#if PLATFORM_WINDOWS
using (var locker = new WindowsFileLocker(GetCacheIndexLockLocation()))
#else
using (var locker = new PosixFileLocker(GetCacheIndexLockLocation()))
#endif
{
if (TryGetFromCache(uri, out fileName))
{
fetchedFiles.Add(fileName, uri);
return(true);
}
if (TryFetchFromUriInner(uri, out fileName))
{
UpdateInCache(uri, fileName);
return(true);
}
}
fileName = null;
return(false);
}
public bool TryFetchFromUri(Uri uri, out string fileName)
{
fileName = null;
if (!Monitor.TryEnter(concurrentLock))
{
Logger.LogAs(this, LogLevel.Error, "Cannot perform concurrent downloads, aborting...");
return(false);
}
#if PLATFORM_WINDOWS
using (var locker = new WindowsFileLocker(GetCacheIndexLockLocation()))
#else
using (var locker = new PosixFileLocker(GetCacheIndexLockLocation()))
#endif
{
if (TryGetFromCache(uri, out fileName))
{
fetchedFiles.Add(fileName, uri);
Monitor.Exit(concurrentLock);
return(true);
}
using (client = new WebClient())
{
fileName = TemporaryFilesManager.Instance.GetTemporaryFile();
try
{
var attempts = 0;
var success = false;
do
{
var downloadProgressHandler = EmulationManager.Instance.ProgressMonitor.Start(GenerateProgressMessage(uri), false, true);
Logger.LogAs(this, LogLevel.Info, "Downloading {0}.", uri);
var now = CustomDateTime.Now;
var bytesDownloaded = 0L;
client.DownloadProgressChanged += (sender, e) =>
{
var newNow = CustomDateTime.Now;
var period = newNow - now;
if (period > progressUpdateThreshold)
{
downloadProgressHandler.UpdateProgress(e.ProgressPercentage,
GenerateProgressMessage(uri,
e.BytesReceived, e.TotalBytesToReceive, e.ProgressPercentage, 1.0 * (e.BytesReceived - bytesDownloaded) / period.TotalSeconds));
now = newNow;
bytesDownloaded = e.BytesReceived;
}
};
var wasCancelled = false;
Exception exception = null;
var resetEvent = new ManualResetEvent(false);
client.DownloadFileCompleted += delegate(object sender, AsyncCompletedEventArgs e)
{
exception = e.Error;
if (e.Cancelled)
{
wasCancelled = true;
}
resetEvent.Set();
downloadProgressHandler.Finish();
};
client.DownloadFileAsync(uri, fileName);
resetEvent.WaitOne();
downloadProgressHandler.Finish();
if (wasCancelled)
{
Logger.LogAs(this, LogLevel.Info, "Download cancelled.");
File.Delete(fileName);
return(false);
}
if (exception != null)
{
var webException = exception as WebException;
File.Delete(fileName);
Logger.LogAs(this, LogLevel.Error, "Failed to download from {0}, reason: {1}.", uri, webException != null ? ResolveWebException(webException) : exception.Message);
return(false);
}
Logger.LogAs(this, LogLevel.Info, "Download done.");
if (uri.ToString().EndsWith(".gz", StringComparison.InvariantCulture))
{
var decompressionProgressHandler = EmulationManager.Instance.ProgressMonitor.Start(string.Format("Decompressing {0}", uri), false, false);
Logger.LogAs(this, LogLevel.Info, "Decompressing {0}.", uri);
var decompressedFile = TemporaryFilesManager.Instance.GetTemporaryFile();
using (var gzipStream = new GZipStream(File.OpenRead(fileName), CompressionMode.Decompress))
using (var outputStream = File.OpenWrite(decompressedFile))
{
gzipStream.CopyTo(outputStream);
}
fileName = decompressedFile;
Logger.LogAs(this, LogLevel.Info, "Decompression done");
decompressionProgressHandler.Finish();
}
}while (!(success = UpdateInCache(uri, fileName)) && attempts++ < 2);
if (!success)
{
Logger.LogAs(this, LogLevel.Error, "Download failed {0} times, wrong checksum or size, aborting.", attempts);
File.Delete(fileName);
return(false);
}
fetchedFiles.Add(fileName, uri);
return(true);
}
finally
{
Monitor.Exit(concurrentLock);
}
}
}
}
