public unsafe static FileDescriptor OpenNetMap(string interfaceName, int ringId, NetMapRequestFlags flags, out NetMapRequest returnedRequest)
{
var fd = Open("/dev/netmap", OpenFlags.O_RDWR);
if (!fd.IsValid)
{
ExceptionHelper.ThrowInvalidOperation($"Unable to open the /dev/netmap device {fd}");
}
var request = new NetMapRequest
{
nr_cmd = 0,
nr_ringid = (ushort)ringId,
nr_version = NETMAP_API,
nr_flags = flags,
};
var textbytes = Encoding.ASCII.GetBytes(interfaceName + "\0");
fixed(void *txtPtr = textbytes)
{
Buffer.MemoryCopy(txtPtr, request.nr_name, textbytes.Length, textbytes.Length);
}
if (IOCtl(fd, IOControlCommand.NIOCREGIF, ref request) != 0)
{
ExceptionHelper.ThrowInvalidOperation("Failed to open an FD for a single ring");
}
returnedRequest = request;
return(fd);
}
internal static extern int IOCtl(FileDescriptor descriptor, IOControlCommand request, ref NetMapRequest data);
