-/* $Cambridge: exim/src/src/daemon.c,v 1.2 2004/11/10 10:29:56 ph10 Exp $ */
+/* $Cambridge: exim/src/src/daemon.c,v 1.4 2005/01/04 10:00:42 ph10 Exp $ */
/*************************************************
* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2004 */
+/* Copyright (c) University of Cambridge 1995 - 2005 */
/* See the file NOTICE for conditions of use and distribution. */
/* Functions concerned with running Exim as a daemon */
main_sigchld_handler(int sig)
{
sig = sig; /* Keep picky compilers happy */
+os_non_restarting_signal(SIGCHLD, SIG_DFL);
sigchld_seen = TRUE;
-signal(SIGCHLD, SIG_DFL);
}
/* Set up the handler for termination of child processes. */
sigchld_seen = FALSE;
-signal(SIGCHLD, main_sigchld_handler);
+os_non_restarting_signal(SIGCHLD, main_sigchld_handler);
/* If we are to run the queue periodically, pretend the alarm has just gone
off. This will cause the first queue-runner to get kicked off straight away. */
}
DEBUG(D_any) debug_printf("Listening...\n");
+
+ /* In rare cases we may have had a SIGCHLD signal in the time between
+ setting the handler (below) and getting back here. If so, pretend that the
+ select() was interrupted so that we reap the child. This might still leave
+ a small window when a SIGCHLD could get lost. However, since we use SIGCHLD
+ only to do the reaping more quickly, it shouldn't result in anything other
+ than a delay until something else causes a wake-up. */
+
+ if (sigchld_seen)
+ {
+ lcount = -1;
+ errno = EINTR;
+ }
+ else
+ {
+ lcount = select(max_socket + 1, (SELECT_ARG2_TYPE *)&select_listen,
+ NULL, NULL, NULL);
+ }
- if ((lcount = select(max_socket + 1, (SELECT_ARG2_TYPE *)&select_listen,
- NULL, NULL, NULL)) < 0)
+ if (lcount < 0)
{
select_failed = TRUE;
lcount = 1;
}
-
+
/* Loop for all the sockets that are currently ready to go. If select
- actually failed, we have set the count to 1 and a flag, so as to use the
- common error code for select/accept below. */
+ actually failed, we have set the count to 1 and select_failed=TRUE, so as
+ to use the common error code for select/accept below. */
while (lcount-- > 0)
{
if (sigchld_seen)
{
sigchld_seen = FALSE;
- signal(SIGCHLD, main_sigchld_handler);
+ os_non_restarting_signal(SIGCHLD, main_sigchld_handler);
}
/* Handle being woken by SIGHUP. We know at this point that the result