internal DbConnectionPool GetConnectionPool(DbConnectionFactory connectionFactory)
{
// When this method returns null it indicates that the connection
// factory should not use pooling.
// We don't support connection pooling on Win9x;
// PoolGroupOptions will only be null when we're not supposed to pool
// connections.
DbConnectionPool pool = null;
if (null != _poolGroupOptions)
{
DbConnectionPoolIdentity currentIdentity = DbConnectionPoolIdentity.NoIdentity;
if (_poolGroupOptions.PoolByIdentity)
{
// There is no concept of Windows identity on non-Windows platform. Hence we
// cannot support Windows authentication.
if (!ADP.IsWindows)
{
throw new PlatformNotSupportedException(SR.GetString(SR.ADP_FeatureNotSupportedOnNonWindowsPlatform, DbConnectionStringKeywords.IntegratedSecurity));
}
// if we're pooling by identity (because integrated security is
// being used for these connections) then we need to go out and
// search for the connectionPool that matches the current identity.
currentIdentity = DbConnectionPoolIdentity.GetCurrent();
// If the current token is restricted in some way, then we must
// not attempt to pool these connections.
if (currentIdentity.IsRestricted)
{
currentIdentity = null;
}
}
if (null != currentIdentity)
{
if (!_poolCollection.TryGetValue(currentIdentity, out pool))
{ // find the pool
DbConnectionPoolProviderInfo connectionPoolProviderInfo = connectionFactory.CreateConnectionPoolProviderInfo(this.ConnectionOptions);
// optimistically create pool, but its callbacks are delayed until after actual add
DbConnectionPool newPool = new DbConnectionPool(connectionFactory, this, currentIdentity, connectionPoolProviderInfo);
lock (this)
{
// Did someone already add it to the list?
if (!_poolCollection.TryGetValue(currentIdentity, out pool))
{
if (MarkPoolGroupAsActive())
{
// If we get here, we know for certain that we there isn't
// a pool that matches the current identity, so we have to
// add the optimistically created one
newPool.Startup(); // must start pool before usage
bool addResult = _poolCollection.TryAdd(currentIdentity, newPool);
Debug.Assert(addResult, "No other pool with current identity should exist at this point");
pool = newPool;
newPool = null;
}
else
{
// else pool entry has been disabled so don't create new pools
Debug.Assert(PoolGroupStateDisabled == _state, "state should be disabled");
}
}
else
{
// else found an existing pool to use instead
Debug.Assert(PoolGroupStateActive == _state, "state should be active since a pool exists and lock holds");
}
}
if (null != newPool)
{
// don't need to call connectionFactory.QueuePoolForRelease(newPool) because
// pool callbacks were delayed and no risk of connections being created
newPool.Shutdown();
}
}
// the found pool could be in any state
}
}
if (null == pool)
{
lock (this)
{
// keep the pool entry state active when not pooling
MarkPoolGroupAsActive();
}
}
return(pool);
}
