collectdmon: Added SIGHUP handler to restart collectd.

This might be useful for init scripts and the like to restart the collectd
process only.

Signed-off-by: Sebastian Harl <sh@tokkee.org>
Signed-off-by: Florian Forster <octo@huhu.verplant.org>

diff --git a/src/collectdmon.c b/src/collectdmon.c
index 39dc0f2..0295ad3 100644 (file)
--- a/src/collectdmon.c
+++ b/src/collectdmon.c
@@ -54,7 +54,8 @@
 # define WCOREDUMP(s) 0
 #endif /* ! WCOREDUMP */
 
-static int loop = 0;
+static int loop    = 0;
+static int restart = 0;
 
 static char  *pidfile      = NULL;
 static pid_t  collectd_pid = 0;
@@ -202,11 +203,22 @@ static void sig_int_term_handler (int signo)
        return;
 } /* sig_int_term_handler */
 
+static void sig_hup_handler (int signo)
+{
+       ++restart;
+       return;
+} /* sig_hup_handler */
+
 static void log_status (int status)
 {
        if (WIFEXITED (status)) {
-               syslog (LOG_INFO, "Info: collectd terminated with exit status %i",
-                               WEXITSTATUS (status));
+               if (0 == WEXITSTATUS (status))
+                       syslog (LOG_INFO, "Info: collectd terminated with exit status %i",
+                                       WEXITSTATUS (status));
+               else
+                       syslog (LOG_WARNING,
+                                       "Warning: collectd terminated with exit status %i",
+                                       WEXITSTATUS (status));
        }
        else if (WIFSIGNALED (status)) {
                syslog (LOG_WARNING, "Warning: collectd was terminated by signal %i%s",
@@ -312,6 +324,13 @@ int main (int argc, char **argv)
                return 1;
        }
 
+       sa.sa_handler = sig_hup_handler;
+
+       if (0 != sigaction (SIGHUP, &sa, NULL)) {
+               syslog (LOG_ERR, "Error: sigaction() failed: %s", strerror (errno));
+               return 1;
+       }
+
        sigaddset (&sa.sa_mask, SIGCHLD);
        if (0 != sigprocmask (SIG_BLOCK, &sa.sa_mask, NULL)) {
                syslog (LOG_ERR, "Error: sigprocmask() failed: %s", strerror (errno));
@@ -329,7 +348,7 @@ int main (int argc, char **argv)
                assert (0 < collectd_pid);
                while ((collectd_pid != waitpid (collectd_pid, &status, 0))
                                && (EINTR == errno))
-                       if (0 != loop)
+                       if ((0 != loop) || (0 != restart))
                                collectd_stop ();
 
                collectd_pid = 0;
@@ -337,7 +356,11 @@ int main (int argc, char **argv)
                log_status (status);
                check_respawn ();
 
-               if (0 == loop)
+               if (0 != restart) {
+                       syslog (LOG_INFO, "Info: restarting collectd");
+                       restart = 0;
+               }
+               else if (0 == loop)
                        syslog (LOG_WARNING, "Warning: restarting collectd");
        }