From: tedu <tedu@openbsd.org>
Date: Fri, 16 Oct 2015 20:12:06 +0000 (+0000)
Subject: naddy would like the child to exit when the parent dies.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=c452184f6a6e3c19f4b2f829a2d3ff97c12b3910;p=openbsd

naddy would like the child to exit when the parent dies.
hook up a pipe between them and watch for eof in the child.
---

diff --git a/usr.sbin/rebound/rebound.c b/usr.sbin/rebound/rebound.c
index dcad25a35c1..2c30a28530d 100644
--- a/usr.sbin/rebound/rebound.c
+++ b/usr.sbin/rebound/rebound.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: rebound.c,v 1.23 2015/10/16 18:47:52 tedu Exp $ */
+/* $OpenBSD: rebound.c,v 1.24 2015/10/16 20:12:06 tedu Exp $ */
 /*
  * Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
  *
@@ -356,7 +356,7 @@ readconfig(FILE *conf, struct sockaddr_storage *remoteaddr)
 }
 
 static int
-launch(const char *confname, int ud, int ld, int kq)
+launch(const char *confname, int ud, int ld, int kq, int *pfd)
 {
 	struct sockaddr_storage remoteaddr;
 	struct kevent chlist[2], kev[4];
@@ -377,6 +377,7 @@ launch(const char *confname, int ud, int ld, int kq)
 	if (!debug) {
 		if ((child = fork()))
 			return child;
+		close(pfd[1]);
 	}
 
 	if (!(pwd = getpwnam("_rebound")))
@@ -406,7 +407,8 @@ launch(const char *confname, int ud, int ld, int kq)
 	EV_SET(&kev[0], ud, EVFILT_READ, EV_ADD, 0, 0, NULL);
 	EV_SET(&kev[1], ld, EVFILT_READ, EV_ADD, 0, 0, NULL);
 	EV_SET(&kev[2], SIGHUP, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL);
-	kevent(kq, kev, 3, NULL, 0, NULL);
+	EV_SET(&kev[3], pfd[0], EVFILT_READ, EV_ADD, 0, 0, NULL);
+	kevent(kq, kev, 4, NULL, 0, NULL);
 	signal(SIGHUP, SIG_IGN);
 	logmsg(LOG_INFO, "worker process going to work");
 	while (1) {
@@ -420,6 +422,11 @@ launch(const char *confname, int ud, int ld, int kq)
 			if (kev[i].filter == EVFILT_SIGNAL) {
 				logmsg(LOG_INFO, "hupped, exiting");
 				exit(0);
+			} else if (kev[i].ident == pfd[0]) {
+				if (kev[i].flags & EV_EOF) {
+					logmsg(LOG_INFO, "parent died");
+					exit(0);
+				}
 			} else if (kev[i].ident == ud) {
 				req = newrequest(ud,
 				    (struct sockaddr *)&remoteaddr);
@@ -515,6 +522,7 @@ main(int argc, char **argv)
 	struct sockaddr_in bindaddr;
 	int r, kq, ld, ud, ch;
 	int one;
+	int pfd[2];
 	int childdead, hupped;
 	pid_t child;
 	struct kevent kev;
@@ -570,8 +578,10 @@ main(int argc, char **argv)
 	if (listen(ld, 10) == -1)
 		err(1, "listen");
 
+	pipe(pfd);
+
 	if (debug) {
-		launch(conffile, ud, ld, -1);
+		launch(conffile, ud, ld, -1, pfd);
 		return 1;
 	}
 
@@ -583,7 +593,7 @@ main(int argc, char **argv)
 	while (1) {
 		hupped = 0;
 		childdead = 0;
-		child = launch(conffile, ud, ld, kq);
+		child = launch(conffile, ud, ld, kq, pfd);
 		if (child == -1)
 			logerr("failed to launch");