File 0003-MEDIUM-Improve-signal-handling-in-systemd-... of Package haproxy

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File 0003-MEDIUM-Improve-signal-handling-in-systemd-wrapper.patch of Package haproxy (Revision 40c94017f82c5e40ef434a58a4db1903)

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From 62c8565cd5bbda6ac0dd818fa26922eeaef1605c Mon Sep 17 00:00:00 2001
From: Conrad Hoffmann <conrad@soundcloud.com>
Date: Mon, 28 Jul 2014 23:52:20 +0200
Subject: [PATCH 03/15] MEDIUM: Improve signal handling in systemd wrapper.

Move all code out of the signal handlers, since this is potentially
dangerous. To make sure the signal handlers behave as expected, use
sigaction() instead of signal(). That also obsoletes messing with
the signal mask after restart.

Signed-off-by: Conrad Hoffmann <conrad@soundcloud.com>
(cherry picked from commit 5b5ea9c93384da49eea0f67ebed0966d4167b17a)
---
 src/haproxy-systemd-wrapper.c | 37 ++++++++++++++++++++++++-------------
 1 file changed, 24 insertions(+), 13 deletions(-)

diff --git a/src/haproxy-systemd-wrapper.c b/src/haproxy-systemd-wrapper.c
index 529b213..90a94ce 100644
--- a/src/haproxy-systemd-wrapper.c
+++ b/src/haproxy-systemd-wrapper.c
@@ -22,6 +22,8 @@
 #define SD_DEBUG "<7>"
 #define SD_NOTICE "<5>"
 
+static volatile sig_atomic_t caught_signal;
+
 static char *pid_file = "/run/haproxy.pid";
 static int wrapper_argc;
 static char **wrapper_argv;
@@ -103,7 +105,12 @@ static int read_pids(char ***pid_strv)
 	return read;
 }
 
-static void sigusr2_handler(int signum __attribute__((unused)))
+static void signal_handler(int signum)
+{
+	caught_signal = signum;
+}
+
+static void do_restart(void)
 {
 	setenv(REEXEC_FLAG, "1", 1);
 	fprintf(stderr, SD_NOTICE "haproxy-systemd-wrapper: re-executing\n");
@@ -111,7 +118,7 @@ static void sigusr2_handler(int signum __attribute__((unused)))
 	execv(wrapper_argv[0], wrapper_argv);
 }
 
-static void sigint_handler(int signum __attribute__((unused)))
+static void do_shutdown(void)
 {
 	int i, pid;
 	char **pid_strv = NULL;
@@ -147,25 +154,21 @@ int main(int argc, char **argv)
 	--argc; ++argv;
 	init(argc, argv);
 
-	signal(SIGINT, &sigint_handler);
-	signal(SIGUSR2, &sigusr2_handler);
+	struct sigaction sa;
+	memset(&sa, 0, sizeof(struct sigaction));
+	sa.sa_handler = &signal_handler;
+	sigaction(SIGUSR2, &sa, NULL);
+	sigaction(SIGINT, &sa, NULL);
 
 	if (getenv(REEXEC_FLAG) != NULL) {
 		/* We are being re-executed: restart HAProxy gracefully */
 		int i;
 		char **pid_strv = NULL;
 		int nb_pid = read_pids(&pid_strv);
-		sigset_t sigs;
 
 		unsetenv(REEXEC_FLAG);
 		spawn_haproxy(pid_strv, nb_pid);
 
-		/* Unblock SIGUSR2 which was blocked by the signal handler
-		 * before re-exec */
-		sigprocmask(SIG_BLOCK, NULL, &sigs);
-		sigdelset(&sigs, SIGUSR2);
-		sigprocmask(SIG_SETMASK, &sigs, NULL);
-
 		for (i = 0; i < nb_pid; ++i)
 			free(pid_strv[i]);
 		free(pid_strv);
@@ -176,8 +179,16 @@ int main(int argc, char **argv)
 	}
 
 	status = -1;
-	while (-1 != wait(&status) || errno == EINTR)
-		;
+	while (-1 != wait(&status) || errno == EINTR) {
+		if (caught_signal == SIGUSR2) {
+			caught_signal = 0;
+			do_restart();
+		}
+		else if (caught_signal == SIGINT) {
+			caught_signal = 0;
+			do_shutdown();
+		}
+	}
 
 	fprintf(stderr, SD_NOTICE "haproxy-systemd-wrapper: exit, haproxy RC=%d\n",
 			status);
-- 
1.8.4.5

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File 0003-MEDIUM-Improve-signal-handling-in-systemd-wrapper.patch of Package haproxy (Revision 40c94017f82c5e40ef434a58a4db1903)

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