public async Task <IEnumerable <IPlcAlarm> > ReadPendingAlarmsAsync()
{
if (ConnectionState != ConnectionState.Opened)
{
ThrowHelper.ThrowNotConnectedException();
}
var id = GetNextReferenceId();
var sequenceNumber = (byte)0x00;
var alarms = new List <IPlcAlarm>();
IMemoryOwner <byte> memoryOwner = null;
var currentPosition = 0;
var totalLength = 0;
try
{
S7PendingAlarmAckDatagram alarmResults = null;
do
{
using (var dg = S7UserDataDatagram.TranslateToMemory(S7UserDataDatagram.BuildPendingAlarmRequest(_s7Context, id, sequenceNumber), out var memoryLength))
{
using (var sendData = _transport.Build(dg.Memory.Slice(0, memoryLength), out var sendLength))
{
CallbackHandler <S7PendingAlarmAckDatagram> cbh;
using (await SemaphoreGuard.Async(_concurrentJobs).ConfigureAwait(false))
{
cbh = new CallbackHandler <S7PendingAlarmAckDatagram>(id);
_alarmHandler.TryAdd(cbh.Id, cbh);
try
{
if (await _transport.Client.SendAsync(sendData.Memory.Slice(0, sendLength)).ConfigureAwait(false) != SocketError.Success)
{
return(null);
}
alarmResults = await cbh.Event.WaitAsync(_s7Context.Timeout).ConfigureAwait(false);
}
finally
{
_alarmHandler.TryRemove(cbh.Id, out _);
}
}
HandleErrorResult(id, cbh, alarmResults);
if (alarmResults.UserData.Data.UserDataLength > 4)
{
if (memoryOwner == null)
{
totalLength = BinaryPrimitives.ReadUInt16BigEndian(alarmResults.UserData.Data.Data.Span.Slice(4, 2)) + 6; // 6 is the header
memoryOwner = MemoryPool <byte> .Shared.Rent(totalLength);
}
alarmResults.UserData.Data.Data.CopyTo(memoryOwner.Memory.Slice(currentPosition, alarmResults.UserData.Data.Data.Length));
currentPosition += alarmResults.UserData.Data.Data.Length;
sequenceNumber = alarmResults.UserData.Parameter.SequenceNumber;
}
else
{
totalLength = 0;
}
}
}
} while (alarmResults.UserData.Parameter.LastDataUnit == 0x01);
if (memoryOwner != null)
{
alarms = S7PendingAlarmAckDatagram.TranslateFromSslData(memoryOwner.Memory, totalLength);
}
}
finally
{
memoryOwner?.Dispose();
}
return(alarms);
}
public async Task <IEnumerable <IPlcAlarm> > ReadPendingAlarmsAsync()
{
if (_closeCalled || ConnectionState != ConnectionState.Opened)
{
ThrowHelper.ThrowNotConnectedException();
}
var id = GetNextReferenceId();
var sequenceNumber = (byte)0x00;
var alarms = new List <IPlcAlarm>();
IMemoryOwner <byte> memoryOwner = null;
var currentPosition = 0;
var totalLength = 0;
try
{
S7PendingAlarmAckDatagram alarmResults = null;
do
{
using (var dg = S7UserDataDatagram.TranslateToMemory(S7UserDataDatagram.BuildPendingAlarmRequest(_s7Context, id, sequenceNumber), out var memoryLength))
{
using (var sendData = _transport.Build(dg.Memory.Slice(0, memoryLength), out var sendLength))
{
CallbackHandler <S7PendingAlarmAckDatagram> cbh = null;
try
{
using (await SemaphoreGuard.Async(_concurrentJobs).ConfigureAwait(false))
{
cbh = new CallbackHandler <S7PendingAlarmAckDatagram>(id);
if (_alarmHandler.TryAdd(id, cbh))
{
_logger?.LogTrace("Alarmhandler with id {id} was added.", id);
try
{
if (await _transport.Connection.SendAsync(sendData.Memory.Slice(0, sendLength)).ConfigureAwait(false) != SocketError.Success)
{
// we return false, because if one send faild we expect also all other ones failed.
_logger?.LogWarning("Could not send read pending alarm package with reference <{id}>.", id);
return(null);
}
alarmResults = await cbh.Event.WaitAsync(_s7Context.Timeout).ConfigureAwait(false);
}
finally
{
_alarmHandler.TryRemove(id, out _);
_logger?.LogTrace("Alarmhandler with id {id} was removed.", id);
}
}
else
{
_logger?.LogWarning("Could not add pending alarm handler with reference <{id}>.", id);
}
}
}
catch (ObjectDisposedException)
{
if (cbh == null)
{
return(alarms); // client was shut down without any result, so we return an empty list.
}
// if we have a result we could handle it.
}
HandleErrorResult(id, cbh, alarmResults);
if (alarmResults.UserData.Data.UserDataLength > 4)
{
if (memoryOwner == null)
{
totalLength = BinaryPrimitives.ReadUInt16BigEndian(alarmResults.UserData.Data.Data.Span.Slice(4, 2)) + 6; // 6 is the header
memoryOwner = MemoryPool <byte> .Shared.Rent(totalLength);
}
alarmResults.UserData.Data.Data.CopyTo(memoryOwner.Memory.Slice(currentPosition, alarmResults.UserData.Data.Data.Length));
currentPosition += alarmResults.UserData.Data.Data.Length;
sequenceNumber = alarmResults.UserData.Parameter.SequenceNumber;
}
else
{
totalLength = 0;
}
}
}
} while (alarmResults.UserData.Parameter.LastDataUnit == 0x01);
if (memoryOwner != null)
{
alarms = S7PendingAlarmAckDatagram.TranslateFromSslData(memoryOwner.Memory, totalLength);
}
}
finally
{
memoryOwner?.Dispose();
}
return(alarms);
}