From: Vincent Bernat <vincent.bernat@dailymotion.com>
Date: Mon, 15 Jul 2013 13:28:46 +0000 (+0200)
Subject: priv: use `sigaction()` instead of `signal()` to install non-default signals
X-Git-Tag: 0.7.7~44
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5c4fa9bdc202c7f474cb50f77a79acbea2abd009;p=thirdparty%2Flldpd.git

priv: use `sigaction()` instead of `signal()` to install non-default signals

`signal()` is not portable to install non-default signals.
---

diff --git a/src/daemon/priv.c b/src/daemon/priv.c
index 6b65e911..c5e630ae 100644
--- a/src/daemon/priv.c
+++ b/src/daemon/priv.c
@@ -492,12 +492,22 @@ priv_init(const char *chrootdir, int ctl, uid_t uid, gid_t gid)
 		if (atexit(priv_exit) != 0)
 			fatal("privsep", "unable to set exit function");
 
-		signal(SIGALRM, sig_pass_to_chld);
-		signal(SIGTERM, sig_pass_to_chld);
-		signal(SIGHUP, sig_pass_to_chld);
-		signal(SIGINT, sig_pass_to_chld);
-		signal(SIGQUIT, sig_pass_to_chld);
-		signal(SIGCHLD, sig_chld);
+		/* Install signal handlers */
+		const struct sigaction pass_to_child = {
+			.sa_handler = sig_pass_to_chld,
+			.sa_flags = SA_RESTART
+		};
+		sigaction(SIGALRM, &pass_to_child, NULL);
+		sigaction(SIGTERM, &pass_to_child, NULL);
+		sigaction(SIGHUP,  &pass_to_child, NULL);
+		sigaction(SIGINT,  &pass_to_child, NULL);
+		sigaction(SIGQUIT, &pass_to_child, NULL);
+		const struct sigaction child = {
+			.sa_handler = sig_chld,
+			.sa_flags = SA_RESTART
+		};
+		sigaction(SIGCHLD, &child, NULL);
+
                 if (waitpid(monitored, &status, WNOHANG) != 0)
                         /* Child is already dead */
                         _exit(1);