nfs-utils - 3 of 6 -statd - Ensure child process is running for before the parent exits

@@ -46,6 +46,7 @@ char *  SM_STAT_PATH = DEFAULT_SM_STAT_P
 
 short int restart = 0;
 int	run_mode = 0;		/* foreground logging mode */
+int pfds[2] = {-1, -1};            /* pipe fds */
 
 /* LH - I had these local to main, but it seemed silly to have 
  * two copies of each - one in main(), one static in log.c... 

@@ -79,14 +80,20 @@ extern void simulator (int, char **);
  */
 static const char *piddir="/var/run/rpc.statd";
 static const char *pidfile="/var/run/rpc.statd/rpc.statd.pid";
+static const char *mypidfile = NULL;
 static void
 delete_pidfile(void)
 {
-	if (unlink(pidfile) < 0) {
-		log(L_WARNING,"Unlinking %s failed: errno %d (%s)\n", pidfile,
-			errno, strerror(errno));
+	/*
+	 * Only delete the pidfile if this is
+	 * the process that created it
+	 */ 
+	if (mypidfile) {
+		if (unlink(mypidfile) < 0) {
+			log(L_WARNING,"Unlinking %s failed: errno %d (%s)\n", mypidfile,
+				errno, strerror(errno));
+		}
 	}
-
 	return;
 }
 static void

@@ -115,9 +122,20 @@ create_pidfile(void)
 		log(L_WARNING,"Closing %s failed: errno %d (%s)\n", pidfile,
 			errno, strerror(errno));
 	}
+	mypidfile = pidfile;
 
 	return;
 }
+/*
+ * Called when the child exits
+ */
+static void
+child_exit(void)
+{
+	delete_pidfile();
+	if (pfds[1] > -1)
+		close(pfds[1]);
+}
 
 /*
  * Privilege dropper

@@ -254,6 +272,7 @@ int main (int argc, char **argv)
 	int pid;
 	int arg;
 	int port = 0, out_port = 0;
+	int status=-1;
 
 	/* Default: daemon mode, no other options */
 	run_mode = 0;

@@ -373,11 +392,24 @@ int main (int argc, char **argv)
 	if (!(run_mode & MODE_NODAEMON)) {
 		int filedes, fdmax, tempfd;
 
+		if (pipe(pfds) < 0) {
+			fprintf(stderr, "Unable to create a pipe(2):"
+				" errno %d (%s)\n", errno, strerror(errno));
+			exit(-1);
+		}
 		if ((pid = fork ()) < 0) {
 			perror ("Could not fork");
-			exit (1);
+			exit(-1);
 		} else if (pid != 0) {
 			/* Parent. */
+			/*
+			 * Wait for status from the child 
+			 */
+			close(pfds[1]);
+			if (read(pfds[0], &status, sizeof(status)) < 1)
+				exit(-1); /* the child died */
+			if (status != 0)
+				exit(-1); /* the child failed */
 			exit (0);
 		}
 		/* Child.	*/

@@ -390,13 +422,16 @@ int main (int argc, char **argv)
 		close(2); dup2(tempfd, 2);
 		fdmax = sysconf (_SC_OPEN_MAX);
 		for (filedes = 3; filedes < fdmax; filedes++) {
-			close (filedes);
+			if (filedes != pfds[1]) 
+				close (filedes);
 		}
+		atexit(child_exit);
 	}
 
 	log_init (name_p, version_p);
 	create_pidfile();
-	atexit(delete_pidfile);
+	if (run_mode & MODE_NODAEMON)
+		atexit(delete_pidfile);
 
 	/* Child. */
 	signal (SIGHUP, killer);

@@ -432,6 +467,15 @@ int main (int argc, char **argv)
 	if (access(".", R_OK|W_OK|X_OK) != 0)
 		die("Cannot access current directory after dropping privs: access()\n");
 
+	/* Tell the parent everthing is ok... */
+	status=0;
+	if (write(pfds[1], &status, sizeof(status)) < 0) {
+		log(L_WARNING,"Writting to pipe[1] failed: errno %d (%s)\n",
+		errno, strerror(errno));
+	}
+	close(pfds[1]);
+	pfds[1] = -1;
+
 	for (;;) {
 		if (!(run_mode & MODE_NOTIFY_ONLY)) {
 			/* Do not do pmap_unset() when running in notify mode.