static CancellationToken GetCombinedCancellationToken(ref CancellationTokenSource?combinedCts, NpgsqlTimeout timeout, CancellationToken cancellationToken)
{
var finalCt = cancellationToken;
if (timeout.IsSet)
{
combinedCts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
combinedCts.CancelAfter((int)timeout.CheckAndGetTimeLeft().TotalMilliseconds);
finalCt = combinedCts.Token;
}
return(finalCt);
}
/// <summary>
/// Utility that simplifies awaiting a task with a timeout. If the given task does not
/// complete within <paramref name="timeout"/>, a <see cref="TimeoutException"/> is thrown.
/// </summary>
/// <param name="task">The task to be awaited</param>
/// <param name="timeout">How much time to allow <paramref name="task"/> to complete before throwing a <see cref="TimeoutException"/></param>
/// <returns>An awaitable task that represents the original task plus the timeout</returns>
internal static async Task <T> WithTimeout <T>(this Task <T> task, NpgsqlTimeout timeout)
{
if (!timeout.IsSet)
{
return(await task);
}
var timeLeft = timeout.CheckAndGetTimeLeft();
if (task != await Task.WhenAny(task, Task.Delay(timeLeft)))
{
throw new TimeoutException();
}
return(await task);
}
/// <summary>
/// Called exactly once per multiplexing pool, when the first connection is opened, with two goals:
/// 1. Load types and bind the pool-wide type mapper (necessary for binding parameters)
/// 2. Cause any connection exceptions (e.g. bad username) to be thrown from NpgsqlConnection.Open
/// </summary>
internal async Task BootstrapMultiplexing(NpgsqlConnection conn, NpgsqlTimeout timeout, bool async, CancellationToken cancellationToken = default)
{
Debug.Assert(_multiplexing);
var hasSemaphore = async
? await _bootstrapSemaphore !.WaitAsync(timeout.CheckAndGetTimeLeft(), cancellationToken)
: _bootstrapSemaphore !.Wait(timeout.CheckAndGetTimeLeft(), cancellationToken);
// We've timed out - calling Check, to throw the correct exception
if (!hasSemaphore)
{
timeout.Check();
}
try
{
if (IsBootstrapped)
{
return;
}
var connector = await conn.StartBindingScope(ConnectorBindingScope.Connection, timeout, async, cancellationToken);
using var _ = Defer(static conn => conn.EndBindingScope(ConnectorBindingScope.Connection), conn);
