private ObjectPoolWaitHandle CreateWaitHandle(IntPtr handle, bool fMutex)
{
ObjectPoolWaitHandle whandle = new ObjectPoolWaitHandle(fMutex);
whandle.Handle = handle;
return(whandle);
}
public SqlInternalConnection GetConnection(out bool isInTransaction)
{
SqlInternalConnection con = null;
isInTransaction = false;
if (_state != State.Running)
{
return(null);
}
// Try to get from the context if we're context specific:
con = TryGetResourceFromContext(out isInTransaction);
if (null == con)
{
_poolCounter.Modify(cAddWait);
}
ObjectPoolWaitHandle[] localWaitHandles = _waitHandles;
while (con == null)
{
int r = WaitHandle.WaitAny(localWaitHandles, _ctrl.CreationTimeout, false);
// From the WaitAny docs: "If more than one object became signaled during
// the call, this is the array index of the signaled object with the
// smallest index value of all the signaled objects." This is important
// so that the free object signal will be returned before a creation
// signal.
if (r == WAIT_TIMEOUT)
{
_poolCounter.Modify(-cAddWait);
return(null);
}
else if (r == ERROR_HANDLE)
{
// Throw the error that PoolCreateRequest stashed.
_poolCounter.Modify(-cAddWait);
throw _resError;
}
else if (r == CREATION_HANDLE)
{
try {
try {
con = UserCreateRequest();
if (null != con)
{
_poolCounter.Modify(-cAddWait);
}
else
{
// If we were not able to create a connection, check to see if
// we reached MaxPool. If so, we will no longer wait on the
// CreationHandle, but instead wait for a free connection or
// the timeout.
// BUG - if we receive the CreationHandle midway into the wait
// period and re-wait, we will be waiting on the full period
if (_poolCounter.TotalCount == _ctrl.MaxPool)
{
if (!CheckForDeadConnections())
{
// modify handle array not to wait on creation mutex anymore
localWaitHandles = new ObjectPoolWaitHandle[2];
localWaitHandles[0] = _waitHandles[0];
localWaitHandles[1] = _waitHandles[1];
}
}
}
}
finally { // ReleaseMutex
_creationMutex.ReleaseMutex();
}
}
catch { // MDAC 80973
throw;
}
}
else
{
//
// guaranteed available inventory
//
_poolCounter.Modify(-cAddWait - cAddFree);
con = GetFromPool();
}
}
Debug.Assert(con != null, "Failed to create pooled object, resulted in null instance.");
return(con);
}
