From bf1c645a89c2c6df3c35cf489b3dba53e91e69c5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kristoffer=20Gr=C3=B6nlund?= <krig@koru.se>
Date: Fri, 22 Nov 2013 10:47:27 +0100
Subject: [PATCH] MEDIUM: haproxy-systemd-wrapper: Revised implementation

* Locate haproxy using location of the wrapper
* Kill children when killed
* Write information to stdout
---
 src/haproxy-systemd-wrapper.c | 57 +++++++++++++++++++++++++++++++++++++------
 1 file changed, 50 insertions(+), 7 deletions(-)

diff --git a/src/haproxy-systemd-wrapper.c b/src/haproxy-systemd-wrapper.c
index fb1a7fd92724..4ca86dd3b8c0 100644
--- a/src/haproxy-systemd-wrapper.c
+++ b/src/haproxy-systemd-wrapper.c
@@ -22,15 +22,30 @@ static char *pid_file = "/run/haproxy.pid";
 static int main_argc;
 static char **main_argv;
 
+static void locate_haproxy(char *buffer, size_t buffer_size)
+{
+	char* end;
+	readlink("/proc/self/exe", buffer, buffer_size);
+	end = strrchr(buffer, '/');
+	if (end == NULL)
+		strncpy(buffer, "/usr/sbin/haproxy", buffer_size);
+	end[1] = '\0';
+	strncat(buffer, "haproxy", buffer_size);
+}
+
 static void spawn_haproxy(char **pid_strv, int nb_pid)
 {
-	pid_t pid = fork();
+	char haproxy_bin[512];
+	pid_t pid;
+
+	pid = fork();
 	if (!pid) {
 		/* 3 for "haproxy -Ds -sf" */
 		char **argv = calloc(4 + main_argc + nb_pid + 1, sizeof(char *));
 		int i;
 		int argno = 0;
-		argv[argno++] = SBINDIR"/haproxy";
+		locate_haproxy(haproxy_bin, 512);
+		argv[argno++] = haproxy_bin;
 		for (i = 0; i < main_argc; ++i)
 			argv[argno++] = main_argv[i];
 		argv[argno++] = "-Ds";
@@ -40,6 +55,12 @@ static void spawn_haproxy(char **pid_strv, int nb_pid)
 				argv[argno++] = pid_strv[i];
 		}
 		argv[argno] = NULL;
+
+		printf("%s", "haproxy-systemd-wrapper: executing ");
+		for (i = 0; argv[i]; ++i)
+			printf("%s ", argv[i]);
+		puts("");
+
 		execv(argv[0], argv);
 		exit(0);
 	}
@@ -68,7 +89,7 @@ static int read_pids(char ***pid_strv)
 	return read;
 }
 
-static void signal_handler(int signum __attribute__((unused)))
+static void sigusr2_handler(int signum __attribute__((unused)))
 {
 	int i;
 	char **pid_strv = NULL;
@@ -81,6 +102,22 @@ static void signal_handler(int signum __attribute__((unused)))
 	free(pid_strv);
 }
 
+static void sigint_handler(int signum __attribute__((unused)))
+{
+	int i, pid;
+	char **pid_strv = NULL;
+	int nb_pid = read_pids(&pid_strv);
+	for (i = 0; i < nb_pid; ++i) {
+		pid = atoi(pid_strv[i]);
+		if (pid > 0) {
+			printf("haproxy-systemd-wrapper: SIGINT -> %d\n", pid);
+			kill(pid, SIGINT);
+			free(pid_strv[i]);
+		}
+	}
+	free(pid_strv);
+}
+
 static void init(int argc, char **argv)
 {
 	while (argc > 1) {
@@ -96,16 +133,22 @@ static void init(int argc, char **argv)
 
 int main(int argc, char **argv)
 {
+	int status;
+
 	--argc; ++argv;
-        main_argc = argc;
-        main_argv = argv;
+	main_argc = argc;
+	main_argv = argv;
 
 	init(argc, argv);
 
-	signal(SIGUSR2, &signal_handler);
+	signal(SIGINT, &sigint_handler);
+	signal(SIGUSR2, &sigusr2_handler);
 
 	spawn_haproxy(NULL, 0);
-	while (-1 != wait(NULL) || errno == EINTR);
+	status = -1;
+	while (-1 != wait(&status) || errno == EINTR)
+		;
 
+	printf("haproxy-systemd-wrapper: exit, haproxy RC=%d\n", status);
 	return EXIT_SUCCESS;
 }
-- 
1.8.4