Add handler for recovery of bad file descriptors
authorWilfried Goesgens <dothebart@citadel.org>
Wed, 5 Jun 2013 23:06:30 +0000 (01:06 +0200)
committerWilfried Goesgens <dothebart@citadel.org>
Wed, 5 Jun 2013 23:06:30 +0000 (01:06 +0200)
citadel/sysdep.c

index a6b225f..f8ff6df 100644 (file)
@@ -1142,6 +1142,87 @@ int convert_login(char NameToConvert[]) {
 
 
 
+void HuntBadSession(void)
+{
+       int highest;
+       CitContext *ptr;
+       fd_set readfds;
+       struct timeval tv;
+       struct ServiceFunctionHook *serviceptr;
+
+
+
+       /* Next, add all of the client sockets. */
+       begin_critical_section(S_SESSION_TABLE);
+       for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
+               if ((ptr->state == CON_SYS) && (ptr->client_socket == 0))
+                       continue;
+               /* Initialize the fdset. */
+               FD_ZERO(&readfds);
+               highest = 0;
+               tv.tv_sec = 0;          /* wake up every second if no input */
+               tv.tv_usec = 0;
+
+               /* Don't select on dead sessions, only truly idle ones */
+               if (    (ptr->state == CON_IDLE)
+                       && (ptr->kill_me == 0)
+                       && (ptr->client_socket > 0)
+                       ) {
+                       FD_SET(ptr->client_socket, &readfds);
+                       if (ptr->client_socket > highest)
+                               highest = ptr->client_socket;
+                       
+                       if ((select(highest + 1, &readfds, NULL, NULL, &tv) < 0) &&
+                           (errno == EBADF))
+                       {
+                               /* Gotcha! */
+                               syslog(LOG_EMERG,
+                                      "Killing Session CC[%d] bad FD: [%d:%d] User[%s] Host[%s:%s]\n",
+                                      ptr->cs_pid,
+                                      ptr->client_socket,
+                                      ptr->is_local_socket,
+                                      ptr->curr_user,
+                                      ptr->cs_host,ptr->cs_addr);
+
+                               ptr->kill_me = 1;
+                               ptr->client_socket = -1;
+                               break;
+                       }
+               }
+               
+       }
+       end_critical_section(S_SESSION_TABLE);
+
+
+       /* First, add the various master sockets to the fdset. */
+       for (serviceptr = ServiceHookTable; serviceptr != NULL; serviceptr = serviceptr->next ) {
+
+               /* Initialize the fdset. */
+               highest = 0;
+               tv.tv_sec = 0;          /* wake up every second if no input */
+               tv.tv_usec = 0;
+
+               FD_SET(serviceptr->msock, &readfds);
+               if (serviceptr->msock > highest) {
+                       highest = serviceptr->msock;
+               }
+               if ((select(highest + 1, &readfds, NULL, NULL, &tv) < 0) &&
+                   (errno == EBADF))
+               {
+                       /* Gotcha! server socket dead? commit suicide! */
+                       syslog(LOG_EMERG,
+                              "Found bad FD: %d and its a server socket! Shutting Down!\n",
+                              serviceptr->msock);
+
+                       server_shutting_down = 1;
+                       break;
+               }
+       }
+
+
+}
+
+
 /* 
  * This loop just keeps going and going and going...
  */
@@ -1235,7 +1316,8 @@ do_select:        force_purge = 0;
                 */
                if (retval < 0) {
                        if (errno == EBADF) {
-                               syslog(LOG_NOTICE, "select() failed: (%s)\n", strerror(errno));
+                               syslog(LOG_EMERG, "select() failed: (%s)\n", strerror(errno));
+                               HuntBadSession ();
                                goto do_select;
                        }
                        if (errno != EINTR) {