public Archiver(string outputFile, int fileAlignment)
{
archiveFile = outputFile;
newWriteSignal = new Semaphore(0, Int32.MaxValue);
exitEvent = new ManualResetEvent(false);
writeData = new List <byte[]>(4000);
outstandingReads = new GT2.RefCounter();
wasFinished = 0;
writeThread = new Thread(new ParameterizedThreadStart(WriteThread));
writeThread.SetApartmentState(ApartmentState.STA);
#if DEBUG
writeThread.Name = "Archiver Write Thread";
#endif
writeThread.Start(--fileAlignment);
}
private void WriteThread(object o)
{
#if TEST_AS_FRENCH
Tools.SetThreadToFrench();
#endif
int fileAlignment = (int)o;
string idxFile = Path.ChangeExtension(archiveFile, ".idx");
MemoryStream memoryIdx = new MemoryStream(4000 * 4);
int bytesWrittenSoFar = 0;
int writeIndexSoFar = 0;
GT2.RefCounter completeWriteCount = new GT2.RefCounter();
FileStream archive = new FileStream(archiveFile, FileMode.Create, FileAccess.Write, FileShare.None, UInt16.MaxValue, true);
using (BinaryWriter idxWriter = new BinaryWriter(memoryIdx))
{
WaitHandle[] waitables = new WaitHandle[2] {
newWriteSignal, exitEvent
};
bool exitLoop = false;
while (!exitLoop)
{
int signalled = WaitHandle.WaitAny(waitables, Timeout.Infinite, false);
if (signalled == 0)
{
int count;
lock (writeData)
{
count = writeData.Count;
}
while (writeIndexSoFar < count)
{
// the reads can complete out of order, but we need to write the archive file
// in order. So if the alert we got wasn't for the next file, go back and wait
// this is also why it's a while loop, so that when we eventually get the signal
// for the next file, we can process the other ones we've aleady seen the signal for
byte[] nextData = writeData[writeIndexSoFar];
if (nextData != null)
{
WriteState ws = new WriteState(archive, completeWriteCount);
int dataLen = nextData.Length;
int lengthWithAlignment = dataLen;
int padAmount = 0;
if (fileAlignment > 0)
{
lengthWithAlignment = (lengthWithAlignment + fileAlignment) & ~fileAlignment;
padAmount = lengthWithAlignment - dataLen;
Array.Resize(ref nextData, lengthWithAlignment);
}
archive.Position = bytesWrittenSoFar;
archive.BeginWrite(nextData, 0, lengthWithAlignment, new AsyncCallback(WriteComplete), ws);
idxWriter.Write(bytesWrittenSoFar | padAmount);
bytesWrittenSoFar += lengthWithAlignment;
++writeIndexSoFar;
}
}
}
else
{
exitLoop = true;
}
Debug.Assert(signalled >= 0 && signalled <= 1, "Archive write thread got a signal other than 0 or 1!");
}
}
bool cancelled = (Thread.VolatileRead(ref wasFinished) == 0);
if (!cancelled)
{
using (BinaryWriter idxFileWriter = new BinaryWriter(new FileStream(idxFile, FileMode.Create, FileAccess.Write, FileShare.None)))
{
// how many
idxFileWriter.Write(writeIndexSoFar);
// the offsets
idxFileWriter.Write(memoryIdx.ToArray());
// file size
idxFileWriter.Write(bytesWrittenSoFar);
}
}
while (!completeWriteCount.HasReached(writeIndexSoFar))
{
Thread.Sleep(100);
}
archive.Dispose();
if (cancelled)
{
File.Delete(archiveFile);
}
}
public WriteState(FileStream file, GT2.RefCounter count)
{
refCount = count;
archive = file;
}