MINOR: systemd wrapper: improve logging

Use standard error for logging messages, as it seems that this gets
messages to the systemd journal more reliably. Also use systemd's
support for specifying log levels via stderr to apply different levels
to messages.

diff --git a/src/haproxy-systemd-wrapper.c b/src/haproxy-systemd-wrapper.c
index e373483d508587ff07300f7845e5d62c0eea685c..d4baa90c266e0c5ae7cfd4cf3d0a134ee74db717 100644 (file)
--- a/src/haproxy-systemd-wrapper.c
+++ b/src/haproxy-systemd-wrapper.c
@@ -19,6 +19,8 @@
 #include <sys/wait.h>
 
 #define REEXEC_FLAG "HAPROXY_SYSTEMD_REEXEC"
+#define SD_DEBUG "<7>"
+#define SD_NOTICE "<5>"
 
 static char *pid_file = "/run/haproxy.pid";
 static int wrapper_argc;
@@ -68,10 +70,10 @@ static void spawn_haproxy(char **pid_strv, int nb_pid)
                }
                argv[argno] = NULL;
 
-               printf("%s", "haproxy-systemd-wrapper: executing ");
+               fprintf(stderr, SD_DEBUG "haproxy-systemd-wrapper: executing ");
                for (i = 0; argv[i]; ++i)
-                       printf("%s ", argv[i]);
-               puts("");
+                       fprintf(stderr, "%s ", argv[i]);
+               fprintf(stderr, "\n");
 
                execv(argv[0], argv);
                exit(0);
@@ -104,7 +106,7 @@ static int read_pids(char ***pid_strv)
 static void sigusr2_handler(int signum __attribute__((unused)))
 {
        setenv(REEXEC_FLAG, "1", 1);
-       printf("haproxy-systemd-wrapper: re-executing\n");
+       fprintf(stderr, SD_NOTICE "haproxy-systemd-wrapper: re-executing\n");
 
        execv(wrapper_argv[0], wrapper_argv);
 }
@@ -117,7 +119,7 @@ static void sigint_handler(int signum __attribute__((unused)))
        for (i = 0; i < nb_pid; ++i) {
                pid = atoi(pid_strv[i]);
                if (pid > 0) {
-                       printf("haproxy-systemd-wrapper: SIGINT -> %d\n", pid);
+                       fprintf(stderr, SD_DEBUG "haproxy-systemd-wrapper: SIGINT -> %d\n", pid);
                        kill(pid, SIGINT);
                        free(pid_strv[i]);
                }
@@ -180,6 +182,7 @@ int main(int argc, char **argv)
        while (-1 != wait(&status) || errno == EINTR)
                ;
 
-       printf("haproxy-systemd-wrapper: exit, haproxy RC=%d\n", status);
+       fprintf(stderr, SD_NOTICE "haproxy-systemd-wrapper: exit, haproxy RC=%d\n",
+                       status);
        return EXIT_SUCCESS;
 }