listen/select and then accept pattern not working?

[Steve Holle]

We are using select on a telnet server.  If you would like to have the full 
source let me know.  This is how we use it

int RecvTimeout ( int s, char *buf, int len, int timeout )
{
         fd_set fds ;
         int n = 0 ;
         struct timeval tv ;
         // Set up the file descriptor set.
         FD_ZERO(&fds) ;
         FD_SET(s, &fds) ;
         // Set up the struct timeval for the timeout.
         tv.tv_sec = timeout ;
         tv.tv_usec = 0 ;
         // Wait until timeout or data received.
         n = select ( s+1, &fds, NULL, NULL, &tv ) ;
         if ( n == 0  ) return -2 ;                      // Timeout
         if ( n == -1 ) return -1 ;                      // Error
         // data must be here, so do a normal recv
         return recv ( s, buf, len, 0 ) ;
}

static void TelnetReadTask (rtems_task_argument fd)
{
         rtems_unsigned32 count ;
         int n = 0 ;
         char buffer [ MAX_RLC_IN_MESSAGE_SIZE+1 ] = {0};
         TelnetQueue.AquireServerQueues ( fd ) ;
         char SocketOpeningPuke [32] = {0} ;
         n = RecvTimeout ( fd, SocketOpeningPuke, sizeof(buffer), 
READ_TIMEOUT_IN_SECONDS ) ;someday.
         for (;;)
         {
                 n = RecvTimeout ( fd, buffer, sizeof(buffer), 
READ_TIMEOUT_IN_SECONDS ) ;
                 if                      ( n == 0 )
                 {
                         #ifdef TELNET_DISPLAY_ALL
                 telnet_server_ts_cout << "Telnet closed by remote port." 
<< std::endl ;
                         #endif
                         break;
                 }
                 else if ( n == -1 )
                 {
                         #ifdef TELNET_DISPLAY_ALL
                 telnet_server_ts_cout << "Telnet closed by timeout." << 
std::endl ;
                         #endif
                         break;
                 }
                 else if ( n == -2 )
                 {
                         #ifdef TELNET_DISPLAY_ALL
                 telnet_server_ts_cout << "Telnet closed by error." << 
std::endl ;
                         #endif
                         break;
                 }
                 else    // Valid data in buffer
                         TelnetQueue.ServerSend ( fd, buffer, n ) ;
         }
         #ifdef TELNET_DISPLAY_ALL
         telnet_server_ts_cout << "Telnet ReadTask close, Socket " << fd << 
std::endl ;
         #endif
         if (close (fd) < 0)
     telnet_server_ts_cout << "Telnet close Error." << std::endl ;
         rtems_status_code sc = rtems_task_delete (RTEMS_SELF);
   telnet_server_ts_cout << "Telnet task delete Error." << std::endl ;
}


At 11:13 AM 1/14/2005, Karel Gardas wrote:

>Hello,
>
>before going into deep debugging I would like to ask here if there is
>anybody here using select-based server on RTEMS, where server will not use
>blocking accept, but rather just listen on specified port (socket) and
>pass listening fd to the select and when someone is going to connect, it
>then pass changed fd to the accept. So the sequence of commands done on
>socket is:
>
>socket -> bind -> listen -> select (loop with timeout) -<someone is going
>to open connection>--> accept.
>
>My problem is that select does not report activity on listening socket.
>Anybody has already seen this?
>
>Thanks a lot,
>Karel
>PS: Tested on 4-6-branch with its recommended tool-chain for pc386 BSP
>running inside Qemu emulator
>--
>Karel Gardas                  kgardas at objectsecurity.com
>ObjectSecurity Ltd.           http://www.objectsecurity.com

Steve Holle
Link Communications, Inc.
1035 Cerise Rd.
Billings, MT  59101
sholle at link-comm.com