- markus@cvs.openbsd.org 2001/10/09 21:59:41

     [channels.c channels.h serverloop.c session.c session.h]
     simplify session close: no more delayed session_close, no more blocking wait() calls.

1 files changed, 15 insertions, 23 deletions

diff --git a/serverloop.c b/serverloop.c
index d7282fe2a..8a82af55b 100644
--- a/serverloop.c
+++ b/serverloop.c
@@ -35,7 +35,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: serverloop.c,v 1.80 2001/10/09 19:51:18 markus Exp $");
+RCSID("$OpenBSD: serverloop.c,v 1.81 2001/10/09 21:59:41 markus Exp $");
 
 #include "xmalloc.h"
 #include "packet.h"
@@ -674,6 +674,7 @@ server_loop2(Authctxt *authctxt)
         fd_set *readset = NULL, *writeset = NULL;
         int rekeying = 0, max_fd, status, nalloc = 0;
         pid_t pid;
+        sigset_t oset, nset;
 
         debug("Entering interactive session for SSH2.");
 
@@ -696,12 +697,17 @@ server_loop2(Authctxt *authctxt)
                         channel_output_poll();
                 wait_until_can_do_something(&readset, &writeset, &max_fd,
                     &nalloc, 0);
+
+                /* block SIGCHLD while we check for dead children */
+                sigemptyset(&nset);
+                sigaddset(&nset, SIGCHLD);
+                sigprocmask(SIG_BLOCK, &nset, &oset);
                 if (child_terminated) {
                         while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
                                 session_close_by_pid(pid, status);
-                        /* XXX race */
                         child_terminated = 0;
                 }
+                sigprocmask(SIG_SETMASK, &oset, NULL);
                 if (!rekeying)
                         channel_after_select(readset, writeset);
                 process_input(readset);
@@ -709,35 +715,21 @@ server_loop2(Authctxt *authctxt)
                         break;
                 process_output(writeset);
         }
-        /* close all channels, no more reads and writes */
-        channel_close_all();
-
         if (readset)
                 xfree(readset);
         if (writeset)
                 xfree(writeset);
 
-        mysignal(SIGCHLD, SIG_DFL);
+        /* free all channels, no more reads and writes */
+        channel_free_all();
 
-        /* collect dead children */
+        /* collect remaining dead children, XXX not necessary? */
+        mysignal(SIGCHLD, SIG_DFL);
         while ((pid = waitpid(-1, &status, WNOHANG)) > 0)
                 session_close_by_pid(pid, status);
-        /*
-         * there is a race between channel_detach_all() killing remaining
-         * children and children dying before kill()
-         */
-        channel_detach_all();
-
-        while (session_have_children()) {
-                pid = waitpid(-1, &status, 0);
-                if (pid > 0)
-                        session_close_by_pid(pid, status);
-                else {
-                        error("waitpid returned %d: %s", pid, strerror(errno));
-                        break;
-                }
-        }
-        channel_free_all();
+
+        /* close remaining sessions, e.g remove wtmp entries */
+        session_close_all();
 }
 
 static void