Clean Exit of ONC RPC SVC_RUN() with MFC

Question

I'm pretty new to multi-threaded code, so I'm hoping that someone can help me with the problem I have.

I have a multi-part program comprised of an ONC/RPC server and other stuff (the "stuff" isn't really pertinent to my question, but it must be in the program with the server). Because svc_run() never returns I figured that I would put it in its own thread, and at program end I would simply terminate the thread and move on with life.

My program has now, however, expanded and I would like to cleanly, and safely, exit or close the ONC/RPC server, rather than terminate the thread. I cannot, however, figure out how to safely return from svc_run(). Can anyone help with this?

I've found a few other people with the same problem but no one seems to have responded to them. I have tried simply moving svc_run() into the same file as my server_process() function but the structures for fd_set don't get populated correctly (everything is 0), and the function fails.

svc_run() is defined in a dll created with the code found at: http://sourceforge.net/projects/oncrpc-windows/

I'm providing the pertinent elements of my code. Also note that svc_exit() does not seem to be a part of the onc/rpc system I'm currently using.

Sorry for the long question, Thank you,

Lex

Here's my code :

 //Code in Initialization of MFC Dialog
myThread = AfxBeginThread(startServing,NULL,THREAD_PRIORITY_NORMAL,0,0,NULL);

 // Thread that starts the server

 UINT __cdecl startServing(LPVOID pParam)
{
   if(server_process())
    AfxMessageBox(_T("Error Starting the VXI 11 Server."));

   AfxEndThread(0,TRUE); //I never get here.
   return 0;
 }

//How I would like to stop the thread:
void myDlg::OnBnClickedQuit()
{
   DWORD threadStatus;
   endThread = 1; //static or extern that could be monitored if svc_run() 
                  //wasn't in a dll
   threadStatus = WaitForSingleObject(myThread->m_hThread, INFINITE);
   OnOk(); //for the ok modal to close the progam

} 

//How I end up stopping my thread
void myDlg::OnBnClickedQuit()
{
   TerminateThread(myThread->m_hThread,1);
   OnOk(); //for the ok modal to close the progam

} 


int server_process()
{
  //Portmap and server registration code
  .
  .
  .
  .
   svc_run(); //ideally I'd be able to monitor a global in here
   (void)fprintf(stderr, "svc_run returned\n");
#ifdef WIN32
   rpc_nt_exit();
#endif
   return(1);

 }// end of server Process

// Function in the dll I'm calling
void svc_run()
{
#ifdef FD_SETSIZE
        fd_set readfds;
#else
      int readfds;
#endif /* def FD_SETSIZE */
#ifndef WIN32
    extern int errno;
#endif

    for (;;) { 
#ifdef FD_SETSIZE
    readfds = svc_fdset;
#else
    readfds = svc_fds;
#endif /* def FD_SETSIZE */
#ifdef WIN32
    switch (select(0 /* unused in winsock */, &readfds, NULL, NULL,
#else
    switch (select(_rpc_dtablesize(), &readfds, (int *)0, (int *)0,
#endif
               (struct timeval *)0)) {
    case -1:
#ifdef WIN32
        if (WSAerrno == EINTR) {
#else
        if (errno == EINTR) {
#endif
            continue;
        }
        perror("svc_run: - select failed");
        return;
    case 0:
        continue;
    default:
        svc_getreqset(&readfds);
       }
   }
}

Answer 1

Well, the answer is in your question. You have to write your own svc_run() and change the infinite loop with conditional:

while(!done) {
  select(....)
  svc_getreqset(&readfds);
}