internal static int FillFdSetFromSocketList(ref Interop.Sys.FdSet fdset, IList socketList)
{
if (socketList == null || socketList.Count == 0)
{
return(0);
}
int maxFd = -1;
for (int i = 0; i < socketList.Count; i++)
{
var socket = socketList[i] as Socket;
if (socket == null)
{
throw new ArgumentException(SR.Format(SR.net_sockets_select, socketList[i].GetType().FullName, typeof(System.Net.Sockets.Socket).FullName), "socketList");
}
int fd = socket._handle.FileDescriptor;
fdset.Set(fd);
if (fd > maxFd)
{
maxFd = fd;
}
}
return(maxFd + 1);
}
// Transform the list socketList such that the only sockets left are those
// with a file descriptor contained in the array "fileDescriptorArray".
internal static void FilterSocketListUsingFdSet(ref Interop.Sys.FdSet fdset, IList socketList)
{
if (socketList == null || socketList.Count == 0)
{
return;
}
lock (socketList)
{
for (int i = socketList.Count - 1; i >= 0; i--)
{
var socket = (Socket)socketList[i];
if (!fdset.IsSet(socket._handle.FileDescriptor))
{
socketList.RemoveAt(i);
}
}
}
}
public static unsafe SocketError Select(IList checkRead, IList checkWrite, IList checkError, int microseconds)
{
var readSet = new Interop.Sys.FdSet();
int maxReadFd = Socket.FillFdSetFromSocketList(ref readSet, checkRead);
var writeSet = new Interop.Sys.FdSet();
int maxWriteFd = Socket.FillFdSetFromSocketList(ref writeSet, checkWrite);
var errorSet = new Interop.Sys.FdSet();
int maxErrorFd = Socket.FillFdSetFromSocketList(ref errorSet, checkError);
int fdCount = 0;
Interop.Sys.FdSet* readFds = null;
Interop.Sys.FdSet* writeFds = null;
Interop.Sys.FdSet* errorFds = null;
if (maxReadFd != 0)
{
readFds = &readSet;
fdCount = maxReadFd;
}
if (maxWriteFd != 0)
{
writeFds = &writeSet;
if (maxWriteFd > fdCount)
{
fdCount = maxWriteFd;
}
}
if (maxErrorFd != 0)
{
errorFds = &errorSet;
if (maxErrorFd > fdCount)
{
fdCount = maxErrorFd;
}
}
int socketCount;
Interop.Error err = Interop.Sys.Select(fdCount, readFds, writeFds, errorFds, microseconds, &socketCount);
GlobalLog.Print("Socket::Select() Interop.libc.select returns socketCount:" + socketCount);
if (err != Interop.Error.SUCCESS)
{
return GetSocketErrorForErrorCode(err);
}
Socket.FilterSocketListUsingFdSet(ref readSet, checkRead);
Socket.FilterSocketListUsingFdSet(ref writeSet, checkWrite);
Socket.FilterSocketListUsingFdSet(ref errorSet, checkError);
return SocketError.Success;
}
public static unsafe SocketError Poll(SafeCloseSocket handle, int microseconds, SelectMode mode, out bool status)
{
var fdSet = new Interop.Sys.FdSet();
fdSet.Set(handle.FileDescriptor);
int fdCount = 0;
Interop.Sys.FdSet* readFds = null;
Interop.Sys.FdSet* writeFds = null;
Interop.Sys.FdSet* errorFds = null;
switch (mode)
{
case SelectMode.SelectRead:
readFds = &fdSet;
fdCount = handle.FileDescriptor + 1;
break;
case SelectMode.SelectWrite:
writeFds = &fdSet;
fdCount = handle.FileDescriptor + 1;
break;
case SelectMode.SelectError:
errorFds = &fdSet;
fdCount = handle.FileDescriptor + 1;
break;
}
int socketCount = 0;
Interop.Error err = Interop.Sys.Select(fdCount, readFds, writeFds, errorFds, microseconds, &socketCount);
if (err != Interop.Error.SUCCESS)
{
status = false;
return GetSocketErrorForErrorCode(err);
}
status = fdSet.IsSet(handle.FileDescriptor);
return SocketError.Success;
}
