void TryAsyncIO(AsyncIOResult ar, Boolean sync)
{
int read;
if (handle == -1)
{
AsyncIOSetCompleted(ar, sync, new ObjectDisposedException(objectname));
return;
}
if (ar.Operation == 1)
{
read = send(handle, ref ar.Buffer[ar.Offset], (UIntPtr)ar.Length, ar.Flags);
}
else if (ar.Operation == 2)
{
Boolean wasBlocking = Blocking;
Blocking = false;
read = accept4(handle, IntPtr.Zero, IntPtr.Zero, 0x80000);
var err = read == -1 ? Marshal.GetLastWin32Error() : 0;
Blocking = wasBlocking;
if (read != -1)
{
ar.Transferred = read;
AsyncIOSetCompleted(ar, sync, null);
}
else if (err != 11)
{
AsyncIOSetCompleted(ar, sync, new PosixException(err, "accept4"));
}
return;
}
else
{
read = recv(handle, ref ar.Buffer[ar.Offset], (UIntPtr)ar.Length, ar.Flags);
if (read == 0 && ar.Operation == 0)
{
AsyncIOSetCompleted(ar, sync, null);
return;
}
}
if (read == -1 && Marshal.GetLastWin32Error() == 11)
{
read = 0;
}
if (read < 0)
{
AsyncIOSetCompleted(ar, sync, new PosixException(ar.Operation == 1 ? "send" : "recv"));
}
else
{
ar.Offset += read;
ar.Length -= read;
ar.Transferred += read;
if (ar.Length <= 0 || (ar.Transferred > 0 && ar.Operation == 0))
{
AsyncIOSetCompleted(ar, sync, null);
}
}
}
void AsyncIOSetCompleted(AsyncIOResult ar, Boolean synchronous, Exception error)
{
AsyncIOResult call = null;
lock (this) {
if (ar.Operation == 1)
{
if (sendqhead == ar)
{
sendqhead = call = ar.Next;
}
if (sendqtail == ar)
{
sendqtail = null;
}
}
else
{
if (recvqhead == ar)
{
recvqhead = call = ar.Next;
}
if (recvqtail == ar)
{
recvqtail = null;
}
}
ar.Next = null;
}
ar.SetCompleted(synchronous, error);
if (call != null)
{
TryAsyncIO(call, false);
if (!call.IsCompleted)
{
EpollWait(); //request was queued while this one was completing (synchronously, possibly chained)
}
}
}
IAsyncResult BeginAsyncIO(int op, byte[] buffer, int offset, int size, SocketFlags socketFlags, AsyncCallback callback, object state)
{
if (buffer == null)
{
throw new ArgumentNullException("buffer");
}
if (offset < 0 || size < 0 || offset + size > buffer.Length)
{
throw new ArgumentOutOfRangeException("offset");
}
if (handle == -1)
{
throw new ObjectDisposedException(objectname);
}
AsyncIOResult ar = new AsyncIOResult(callback, state)
{
Socket = this,
Buffer = buffer,
Offset = offset,
Length = size,
Flags = ConvertFlags(socketFlags) | 0x40, //flags | MSG_DONTWAIT
Operation = op,
};
Boolean first = false;
lock (this) {
if (op == 1)
{
if (sendqtail == null)
{
first = true;
sendqhead = ar;
asyncwritebusy = 1;
}
else
{
sendqtail.Next = ar;
}
sendqtail = ar;
}
else
{
if (recvqtail == null)
{
first = true;
recvqhead = ar;
asyncreadbusy = 1;
}
else
{
recvqtail.Next = ar;
}
recvqtail = ar;
}
}
if (first)
{
TryAsyncIO(ar, true);
if (op == 1)
{
asyncwritebusy = 0;
}
else
{
asyncreadbusy = 0;
}
if (!ar.IsCompleted || ar.Next != null)
{
EpollWait();
}
}
return(ar);
}
