static async Task RunCanLoopAsync(CancellationToken cancellationToken)
{
var factory = new SocketCanFactory();
var incomingBuffer = new byte[16];
var incomingFrame = new CanFrame();
using (var socket = factory.CreateSocket("can0"))
{
while (true)
{
await socket.ReceiveAsync(incomingBuffer, SocketFlags.None, CancellationToken.None).ConfigureAwait(false);
incomingFrame.Reinitialize(incomingBuffer);
try
{
await socket.SendAsync(new CanFrame { IsExtendedFrame = true, Id = incomingFrame.Id - 1, DataLength = 4 }.FrameBytes, SocketFlags.None).ConfigureAwait(false);
}
catch (SocketException se) when(se.SocketErrorCode == SocketError.NoBufferSpaceAvailable)
{
Console.WriteLine("No buffer space available waiting a few ms");
await Task.Delay(TimeSpan.FromMilliseconds(10), cancellationToken).ConfigureAwait(false);
}
}
}
}
static async Task SimpleLoopBackAsync(string adapter, CancellationToken cancellationToken)
{
var factory = new SocketCanFactory();
var incomingBuffer = new byte[CanFrame.FrameLength];
using var socket = factory.CreateSocket(adapter);
{
Console.WriteLine($"Created adapter: {adapter}");
while (true)
{
await socket.ReceiveAsync(incomingBuffer, SocketFlags.None, CancellationToken.None).ConfigureAwait(false);
var incomingFrame = new CanFrame(incomingBuffer);
Console.WriteLine($"Received {nameof(CanFrame)} Id: {incomingFrame.Id} IsRtr: {incomingFrame.IsRemoteTransmissionRequest} Length: {incomingFrame.DataLength} IsError: {incomingFrame.IsErrorMessage} Data: {ByteArrayToString(incomingFrame.Data)}");
try
{
var sendFrame = new CanFrame {
IsExtendedFrame = true, Id = incomingFrame.Id - 1, DataLength = 4
};
sendFrame.Data[0] = 1;
sendFrame.Data[1] = 2;
sendFrame.Data[2] = 3;
sendFrame.Data[3] = 4;
await socket.SendAsync(sendFrame.FrameBytes, SocketFlags.None).ConfigureAwait(false);
}
catch (SocketException se) when(se.SocketErrorCode == SocketError.NoBufferSpaceAvailable)
{
// Default the buffer space is only 10 message you can extend this on Linux or wait a while before retransmitting.
// RUN: "ip link set can0 txqueuelen 1000" to increase size to 1000 messages where can0 is the name of the SocketCAN interface in Linux
Console.WriteLine("No buffer space available waiting a few ms");
await Task.Delay(TimeSpan.FromMilliseconds(10), cancellationToken).ConfigureAwait(false);
}
}
}
}
