Streamline the daemon shutdown sequence.

Only the parent process handles SIGTERM and SIGINT.  Upon receiving one
of those, it closes all imsg sockets and waitpid() for the children. It
fatal()s if one of the sockets is closed unexpectedly.  Other processes
exit() "normally" when one of the imsg sockets is closed.

ok gilles@ sunil@

1 files changed, 20 insertions, 24 deletions

diff --git a/usr.sbin/smtpd/smtpd.c b/usr.sbin/smtpd/smtpd.c
index 661915d935d..a138840f351 100644
--- a/usr.sbin/smtpd/smtpd.c
+++ b/usr.sbin/smtpd/smtpd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: smtpd.c,v 1.285 2016/09/06 16:34:29 eric Exp $	*/
+/*	$OpenBSD: smtpd.c,v 1.286 2016/09/08 12:06:43 eric Exp $	*/
 
 /*
  * Copyright (c) 2008 Gilles Chehade <gilles@poolp.org>
@@ -60,7 +60,7 @@
 static void parent_imsg(struct mproc *, struct imsg *);
 static void usage(void);
 static int smtpd(void);
-static void parent_shutdown(int);
+static void parent_shutdown(void);
 static void parent_send_config(int, short, void *);
 static void parent_send_config_lka(void);
 static void parent_send_config_pony(void);
@@ -162,8 +162,8 @@ parent_imsg(struct mproc *p, struct imsg *imsg)
 	int			 fd, n, v, ret;
 
 	if (imsg == NULL)
-		exit(1);
-	
+		fatalx("process %s socket closed", p->name);
+
 	if (p->proc == PROC_LKA) {
 		switch (imsg->hdr.type) {
 		case IMSG_LKA_OPEN_FORWARD:
@@ -275,16 +275,16 @@ usage(void)
 }
 
 static void
-parent_shutdown(int ret)
+parent_shutdown(void)
 {
-	void		*iter;
-	struct child	*child;
-	pid_t		 pid;
+	pid_t pid;
 
-	iter = NULL;
-	while (tree_iter(&children, &iter, NULL, (void**)&child))
-		if (child->type == CHILD_DAEMON)
-			kill(child->pid, SIGTERM);
+	mproc_clear(p_ca);
+	mproc_clear(p_pony);
+	mproc_clear(p_control);
+	mproc_clear(p_lka);
+	mproc_clear(p_scheduler);
+	mproc_clear(p_queue);
 
 	do {
 		pid = waitpid(WAIT_MYPGRP, NULL, 0);
@@ -292,8 +292,8 @@ parent_shutdown(int ret)
 
 	unlink(SMTPD_SOCKET);
 
-	log_warnx("warn: parent terminating");
-	exit(ret);
+	log_info("Exiting");
+	exit(0);
 }
 
 static void
@@ -333,16 +333,17 @@ static void
 parent_sig_handler(int sig, short event, void *p)
 {
 	struct child	*child;
-	int		 die = 0, die_gracefully = 0, status, fail;
+	int		 status, fail;
 	pid_t		 pid;
 	char		*cause;
 
 	switch (sig) {
 	case SIGTERM:
 	case SIGINT:
-		log_info("info: %s, shutting down", strsignal(sig));
-		die_gracefully = 1;
-		/* FALLTHROUGH */
+		log_debug("debug: got signal %d", sig);
+		parent_shutdown();
+		/* NOT REACHED */
+
 	case SIGCHLD:
 		do {
 			int len;
@@ -379,7 +380,6 @@ parent_sig_handler(int sig, short event, void *p)
 
 			switch (child->type) {
 			case CHILD_DAEMON:
-				die = 1;
 				if (fail)
 					log_warnx("warn: lost child: %s %s",
 					    child->title, cause);
@@ -434,10 +434,6 @@ parent_sig_handler(int sig, short event, void *p)
 			free(cause);
 		} while (pid > 0 || (pid == -1 && errno == EINTR));
 
-		if (die)
-			parent_shutdown(1);
-		else if (die_gracefully)
-			parent_shutdown(0);
 		break;
 	default:
 		fatalx("smtpd: unexpected signal");
@@ -1597,7 +1593,7 @@ imsg_dispatch(struct mproc *p, struct imsg *imsg)
 	int		msg;
 
 	if (imsg == NULL) {
-		exit(1);
+		imsg_callback(p, imsg);
 		return;
 	}