starter: Check for processes with PIDs stored in pid files.

diff --git a/src/starter/starter.c b/src/starter/starter.c
index d86da21b83f758c1824c312ede7f1caf42fd61a9..814713cdac6a3d9f100c51e8cb9d665a3506dfed 100644 (file)
--- a/src/starter/starter.c
+++ b/src/starter/starter.c
@@ -217,6 +217,36 @@ static void generate_selfcert()
                }
 }
 
+static bool check_pid(char *pid_file)
+{
+       struct stat stb;
+       FILE *pidfile;
+
+       if (stat(pid_file, &stb) == 0)
+       {
+               pidfile = fopen(pid_file, "r");
+               if (pidfile)
+               {
+                       char buf[64];
+                       pid_t pid = 0;
+                       memset(buf, 0, sizeof(buf));
+                       if (fread(buf, 1, sizeof(buf), pidfile))
+                       {
+                               buf[sizeof(buf) - 1] = '\0';
+                               pid = atoi(buf);
+                       }
+                       fclose(pidfile);
+                       if (pid && kill(pid, 0) == 0)
+                       {       /* such a process is running */
+                               return TRUE;
+                       }
+               }
+               plog("removing pidfile '%s', process not running", pid_file);
+               unlink(pid_file);
+       }
+       return FALSE;
+}
+
 static void usage(char *name)
 {
        fprintf(stderr, "Usage: starter [--nofork] [--auto-update <sec>] "
@@ -322,17 +352,19 @@ int main (int argc, char **argv)
                exit(LSB_RC_NOT_ALLOWED);
        }
 
-       if (stat(PLUTO_PID_FILE, &stb) == 0)
+       if (check_pid(PLUTO_PID_FILE))
        {
-               plog("pluto is already running (%s exists) -- skipping pluto start", PLUTO_PID_FILE);
+               plog("pluto is already running (%s exists) -- skipping pluto start",
+                        PLUTO_PID_FILE);
        }
        else
        {
                _action_ |= FLAG_ACTION_START_PLUTO;
        }
-       if (stat(CHARON_PID_FILE, &stb) == 0)
+       if (check_pid(CHARON_PID_FILE))
        {
-               plog("charon is already running (%s exists) -- skipping charon start", CHARON_PID_FILE);
+               plog("charon is already running (%s exists) -- skipping charon start",
+                        CHARON_PID_FILE);
        }
        else
        {
@@ -374,9 +406,10 @@ int main (int argc, char **argv)
 
        last_reload = time_monotonic(NULL);
 
-       if (stat(STARTER_PID_FILE, &stb) == 0)
+       if (check_pid(STARTER_PID_FILE))
        {
-               plog("starter is already running (%s exists) -- no fork done", STARTER_PID_FILE);
+               plog("starter is already running (%s exists) -- no fork done",
+                        STARTER_PID_FILE);
                confread_free(cfg);
                exit(LSB_RC_SUCCESS);
        }