/*
** Name: TxResourceAsyncThreadProcessRequest
**
** Description:
** Perform the prepare-to-commit, commit, or
** rollback on the database.
**
** History:
** 01-Oct-03 (thoda04)
** Created.
*/
/// <summary>
/// Perform the prepare-to-commit, commit, or rollback on the database.
/// </summary>
void TxResourceAsyncThreadProcessRequest(MSDTCRequest request)
{
uint hr=S_OK;
switch(request)
{
case MSDTCRequest.ENLIST:
try
{
trace.write(4, title + ": MSDTCRequest.Enlisting with RM...");
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.Enlisting with RM...");
TxResourceAsync = (ITransactionResourceAsync) this;
XaHelperSinglePipe_EnlistWithRM(
RMCookie,
Transaction, // pass on the incoming ITransaction
TxResourceAsync, // implements ITransactionResourceAsync
out TxEnlistmentAsync);
// receive ITransactionEnlistmentAsync
TxState = TXSTATE.TX_ENLISTED;
trace.write(4, title + ": MSDTCRequest.Enlisted with RM successfully");
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.Enlisted with RM");
}
catch (Exception ex)
{
EnlistmentException = ex;
string s = ex.ToString(); // debugging
// release and clear the RMCookie
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
break;
}
break;
case MSDTCRequest.DELIST:
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.DELIST...");
// make sure the RMCookie is released and cleared
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
break;
case MSDTCRequest.PREPARE:
{
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.PREPARE...");
hr = PrepareTx(); /* call Ingres to prepare-to-commit */
if (hr==S_OK) /* transaction is prepared */
{
TxState = TXSTATE.TX_PREPARED;
}
else
{
RollbackTx(); /* prepare failed; abort the transaction */
TxState = TXSTATE.TX_INVALID_STATE;
}
try
{
TxEnlistmentAsync.PrepareRequestDone(
hr, IntPtr.Zero, IntPtr.Zero);
trace.write(3, title +
": TxEnlistmentAsync.PrepareRequestDone(0X" +
hr.ToString("X8") + ")");
if (debugging)
Console.WriteLine(title + ": PrepareRequestDone called");
/* if hr==S_OK then MS DTC will dispatch the user application
after the pITransaction->commit();
else hr==E_FAIL then DTC will
pITransactionResourceAsync->Release()
*/
if (TxState != TXSTATE.TX_PREPARED)
{
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
}
}
catch (COMException ex)
{
string s = ex.ToString();
trace.write(3, title + ": MSDTCRequest.PREPARE catches COMException. Message=" +
"\"" + ex.Message +"\"");
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
// throw;
}
catch (Exception ex)
{
string s = ex.ToString();
trace.write(3, title + ": MSDTCRequest.PREPARE catches Exception. Message=" +
"\"" + ex.Message + "\"");
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
// throw;
}
break;
}
case MSDTCRequest.PREPARE_E_FAIL:
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.PREPARE_E_FAIL...");
TxEnlistmentAsync.PrepareRequestDone(
E_FAIL, IntPtr.Zero, IntPtr.Zero);
trace.write(3, title +
": TxEnlistmentAsync.PrepareRequestDone(E_FAIL)");
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
break;
case MSDTCRequest.PREPARE_E_UNEXPECTED:
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.PREPARE_E_UNEXPECTED...");
TxEnlistmentAsync.PrepareRequestDone(
E_UNEXPECTED, IntPtr.Zero, IntPtr.Zero);
trace.write(3, title +
": TxEnlistmentAsync.PrepareRequestDone(E_FAIL)");
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
break;
case MSDTCRequest.PREPARE_SINGLE_PHASE:
{
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.PREPARE_SINGLE_PHASE...");
hr = CommitTx(TMONEPHASE); /* single phase commit optimization */
if (hr == S_OK)
{
hr=XACT_S_SINGLEPHASE;
TxState = TXSTATE.TX_ENLISTED;
}
else
TxState = TXSTATE.TX_INVALID_STATE;
try
{
TxEnlistmentAsync.PrepareRequestDone(
hr, IntPtr.Zero, IntPtr.Zero);
trace.write(4, title +
": TxEnlistmentAsync.PrepareRequestDone(0X" +
hr.ToString("X8") + ")");
if (debugging)
Console.WriteLine(title + ": PrepareRequestDone called");
if (hr == XACT_S_SINGLEPHASE)
{
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.PREPARE_SINGLE_PHASE releasing RMCookie...");
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
}
}
catch (Exception ex)
{
string s = ex.ToString();
trace.write(3, title + ": MSDTCRequest.PREPARE_SINGLE_PHASE catches Exception. Message=" +
"\"" + ex.Message + "\"");
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
// throw;
}
break;
}
case MSDTCRequest.COMMIT:
{
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.COMMIT...");
hr = CommitTx();
if (hr == S_OK)
TxState = TXSTATE.TX_ENLISTED;
else
TxState = TXSTATE.TX_INVALID_STATE;
try
{
TxEnlistmentAsync.CommitRequestDone(hr);
trace.write(3, title +
": TxEnlistmentAsync.CommitRequestDone(0X" +
hr.ToString("X8") + ")");
if (debugging)
Console.WriteLine(title + ": CommitRequestDone called... Releasing RMCookie...");
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
}
catch (Exception ex)
{
string s = ex.ToString(); // for debugging; and ign ex
trace.write(3, title + ": MSDTCRequest.COMMIT catches Exception. Message=" +
"\"" + ex.Message + "\"");
}
break;
}
case MSDTCRequest.ABORT:
{
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.ABORT...");
hr = RollbackTx();
TxState = TXSTATE.TX_ABORTED;
try
{
TxEnlistmentAsync.AbortRequestDone(hr);
trace.write(3, title +
": TxEnlistmentAsync.AbortRequestDone(0X" +
hr.ToString("X8") + ")");
if (debugging)
Console.WriteLine(title + ": AbortRequestDone called... Releasing RMCookie...");
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
}
catch (Exception ex)
{
string s = ex.ToString(); // for debugging; and ign ex
trace.write(3, title + ": MSDTCRequest.ABORT catches Exception. Message=" +
"\"" + ex.Message + "\"");
}
break;
}
case MSDTCRequest.TMDOWN:
{
if (debugging)
Console.WriteLine(title + ": MSDTCRequest.TMDOWN...");
RollbackTx();
TxState = TXSTATE.TX_TMDOWN;
XaHelperSinglePipe_ReleaseRMCookie(ref this.RMCookie);
break;
}
default:
break;
} /* end switch */
}
/*
** Name: StartMSDTCRequest
**
** Description:
** Start the TxResourceAsync thread that will asynchronously
** perform the transaction work.
** Called by one of our implentations under MSDTC Proxy thread.
** PrepareRequest() start prepare-to-commit
** CommitRequest() start commit
** AbortRequest() start rollback
** TMDown() notification that Transaction Monitor is down
**
** History:
** 01-Oct-03 (thoda04)
** Created.
*/
/// <summary>
/// Start a MSDTC request on a worker thread.
/// </summary>
/// <param name="request"></param>
/// <returns>True if request was successfully queued.</returns>
bool StartMSDTCRequest(MSDTCRequest request)
{
lock(MSDTCRequestQueue)
{
// first time start the worker thread
if (txResourceAsyncThread == null ||
txResourceAsyncThread.IsAlive == false)
{
// only start the thread if doing the ENLIST
// (which should be the first call).
if (request != MSDTCRequest.ENLIST)
return false; // should not happen, but bulletproof it
// fire up the thread
ThreadStart start =
new ThreadStart(TxResourceAsyncThreadMethod);
txResourceAsyncThread = new Thread(start);
//Set ApartmentState to STA to minimize
//any COM object creation issues.
txResourceAsyncThread.TrySetApartmentState(ApartmentState.STA);
txResourceAsyncThread.Start();
}
// put the request on the dispatch queue
MSDTCRequestQueue.Enqueue(request);
// wait for TxResourceAsync thread to start and give it
// a chance to lock DBC connection before MSDTC Proxy might
// return async control back to application which might try to
// fire off another provider call before COMMIT has a
// chance to finish.
Monitor.Pulse(MSDTCRequestQueue);
Monitor.Wait(MSDTCRequestQueue);
} // end lock
return true; // indicate request was successfully queued
}
