///<summary>
/// This method is responsible to handle all protocol messages sent from the backend.
/// It holds all the logic to do it.
/// To exchange data, it uses a Mediator object from which it reads/writes information
/// to handle backend requests.
/// </summary>
///
internal IEnumerable <IServerResponseObject> ProcessBackendResponsesEnum(
NpgsqlConnector context,
bool cancelRequestCalled)
{
try
{
// Process commandTimeout behavior.
if ((context.Mediator.CommandTimeout > 0) &&
(!CheckForContextSocketAvailability(context)))
{
// If timeout occurs when establishing the session with server then
// throw an exception instead of trying to cancel query. This helps to prevent loop as CancelRequest will also try to stablish a connection and sends commands.
if (!((this is NpgsqlStartupState || this is NpgsqlConnectedState || cancelRequestCalled)))
{
try
{
context.CancelRequest();
foreach (IServerResponseObject obj in ProcessBackendResponsesEnum(context, true))
{
if (obj is IDisposable)
{
(obj as IDisposable).Dispose();
}
}
}
catch
{
}
//We should have gotten an error from CancelRequest(). Whether we did or not, what we
//really have is a timeout exception, and that will be less confusing to the user than
//"operation cancelled by user" or similar, so whatever the case, that is what we'll throw.
// Changed message again to report about the two possible timeouts: connection or command as the establishment timeout only was confusing users when the timeout was a command timeout.
}
throw new NpgsqlException(resman.GetString("Exception_ConnectionOrCommandTimeout"));
}
return(ProcessBackendResponses_Ver_3(context));
}
catch (ThreadAbortException)
{
try
{
context.CancelRequest();
context.Close();
}
catch { }
throw;
}
}
internal IEnumerable <IServerResponseObject> ProcessExistingBackendResponses(NpgsqlConnector context)
{
try
{
return(ProcessBackendResponses_Ver_3(context));
}
catch (ThreadAbortException)
{
try
{
context.CancelRequest();
context.Close();
}
catch { }
throw;
}
}
/// <summary>
/// Attempts to cancel the execution of a <see cref="Npgsql.NpgsqlCommand">NpgsqlCommand</see>.
/// </summary>
/// <remarks>This Method isn't implemented yet.</remarks>
public override void Cancel()
{
try
{
// get copy for thread safety of null test
NpgsqlConnector connector = Connector;
if (connector != null)
{
connector.CancelRequest();
}
}
catch (IOException)
{
Connection.ClearPool();
}
catch (NpgsqlException)
{
// Cancel documentation says the Cancel doesn't throw on failure
}
}
///<summary>
/// This method is responsible to handle all protocol messages sent from the backend.
/// It holds all the logic to do it.
/// To exchange data, it uses a Mediator object from which it reads/writes information
/// to handle backend requests.
/// </summary>
///
internal IEnumerable<IServerResponseObject> ProcessBackendResponsesEnum(
NpgsqlConnector context,
bool cancelRequestCalled)
{
try
{
// Process commandTimeout behavior.
if ((context.Mediator.CommandTimeout > 0) &&
(!CheckForContextSocketAvailability(context, SelectMode.SelectRead)))
{
// If timeout occurs when establishing the session with server then
// throw an exception instead of trying to cancel query. This helps to prevent loop as CancelRequest will also try to stablish a connection and sends commands.
if (!((this is NpgsqlStartupState || this is NpgsqlConnectedState || cancelRequestCalled)))
{
try
{
context.CancelRequest();
foreach (IServerResponseObject obj in ProcessBackendResponsesEnum(context, true))
{
if (obj is IDisposable)
{
(obj as IDisposable).Dispose();
}
}
}
catch
{
}
//We should have gotten an error from CancelRequest(). Whether we did or not, what we
//really have is a timeout exception, and that will be less confusing to the user than
//"operation cancelled by user" or similar, so whatever the case, that is what we'll throw.
// Changed message again to report about the two possible timeouts: connection or command as the establishment timeout only was confusing users when the timeout was a command timeout.
}
throw new NpgsqlException(resman.GetString("Exception_ConnectionOrCommandTimeout"));
}
return ProcessBackendResponses_Ver_3(context);
}
catch (ThreadAbortException)
{
try
{
context.CancelRequest();
context.Close();
}
catch { }
throw;
}
}
internal IEnumerable<IServerResponseObject> ProcessExistingBackendResponses(NpgsqlConnector context)
{
try
{
return ProcessBackendResponses_Ver_3(context);
}
catch (ThreadAbortException)
{
try
{
context.CancelRequest();
context.Close();
}
catch { }
throw;
}
}
