From 4c396b6e2c12dbf3901e23551d16ef8f73dceba6 Mon Sep 17 00:00:00 2001
From: Thomas Haller <thaller@redhat.com>
Date: Fri, 13 Mar 2015 23:06:29 +0100
Subject: [PATCH] main: refactor nm_main_utils_check_pidfile() to exit directly
 on failure

And rename the function to nm_main_utils_ensure_not_running_pidfile()
to match the other _ensure_ functions that exit(1).

Also no longer pass @name to nm_main_utils_ensure_not_running_pidfile()
and use g_get_prgname() instead.
nm_main_utils_ensure_not_running_pidfile() checks that the running
process has the same program name, so this changes behavior if the
user renamed the binary. Before, we would check whether the running
process is named 'NetworkManager' ('nm-iface-helper'). Now we check
whether the process has the same name as the current process.
This means, that if you rename the binary to 'NetworkManager2' we
would now only detect a conflicting 'NetworkManager2'. Before we would
only detect conflicting 'NetworkManager' binaries.

(cherry picked from commit 12ad2c7fe7ebd94c40edd9a28b81ce27563bb2e3)
---
 src/main-utils.c      | 44 +++++++++++++++++++++----------------------
 src/main-utils.h      |  2 +-
 src/main.c            |  4 +---
 src/nm-iface-helper.c |  6 +-----
 4 files changed, 24 insertions(+), 32 deletions(-)

diff --git a/src/main-utils.c b/src/main-utils.c
index bf8eb4b329..f6a2a60e9e 100644
--- a/src/main-utils.c
+++ b/src/main-utils.c
@@ -33,6 +33,7 @@
 #include <glib/gi18n.h>
 #include <gmodule.h>
 
+#include "gsystem-local-alloc.h"
 #include "main-utils.h"
 #include "nm-posix-signals.h"
 #include "nm-logging.h"
@@ -163,59 +164,56 @@ nm_main_utils_ensure_rundir ()
 }
 
 /**
- * nm_main_utils_check_pidfile:
+ * nm_main_utils_ensure_not_running_pidfile:
  * @pidfile: the pid file
- * @name: the process name
  *
  * Checks whether the pidfile already exists and contains PID of a running
  * process.
  *
- * Returns: %TRUE if the specified pidfile already exists and contains the PID
- *  of a running process named @name, or %FALSE if not
+ * Exits with code 1 if a conflicting process is running.
  */
-gboolean
-nm_main_utils_check_pidfile (const char *pidfile, const char *name)
+void
+nm_main_utils_ensure_not_running_pidfile (const char *pidfile)
 {
-	char *contents = NULL;
+	gs_free char *contents = NULL;
+	gs_free char *proc_cmdline = NULL;
 	gsize len = 0;
 	glong pid;
-	char *proc_cmdline = NULL;
-	gboolean nm_running = FALSE;
 	const char *process_name;
+	const char *prgname = g_get_prgname ();
+
+	g_return_if_fail (prgname);
+
+	if (!pidfile || !*pidfile)
+		return;
 
 	if (!g_file_get_contents (pidfile, &contents, &len, NULL))
-		return FALSE;
-
+		return;
 	if (len <= 0)
-		goto done;
+		return;
 
 	errno = 0;
 	pid = strtol (contents, NULL, 10);
 	if (pid <= 0 || pid > 65536 || errno)
-		goto done;
+		return;
 
-	g_free (contents);
+	g_clear_pointer (&contents, g_free);
 	proc_cmdline = g_strdup_printf ("/proc/%ld/cmdline", pid);
 	if (!g_file_get_contents (proc_cmdline, &contents, &len, NULL))
-		goto done;
+		return;
 
 	process_name = strrchr (contents, '/');
 	if (process_name)
 		process_name++;
 	else
 		process_name = contents;
-	if (strcmp (process_name, name) == 0) {
+	if (strcmp (process_name, prgname) == 0) {
 		/* Check that the process exists */
 		if (kill (pid, 0) == 0) {
-			fprintf (stderr, _("%s is already running (pid %ld)\n"), name, pid);
-			nm_running = TRUE;
+			fprintf (stderr, _("%s is already running (pid %ld)\n"), prgname, pid);
+			exit (1);
 		}
 	}
-
-done:
-	g_free (proc_cmdline);
-	g_free (contents);
-	return nm_running;
 }
 
 gboolean
diff --git a/src/main-utils.h b/src/main-utils.h
index 18e7e534bd..3d64535768 100644
--- a/src/main-utils.h
+++ b/src/main-utils.h
@@ -29,7 +29,7 @@ void     nm_main_utils_ensure_rundir (void);
 
 gboolean nm_main_utils_write_pidfile (const char *pidfile);
 
-gboolean nm_main_utils_check_pidfile (const char *pidfile, const char *name);
+void     nm_main_utils_ensure_not_running_pidfile (const char *pidfile);
 
 gboolean nm_main_utils_early_setup (const char *progname,
                                     int *argc,
diff --git a/src/main.c b/src/main.c
index 28d8defa64..6c1fd9960d 100644
--- a/src/main.c
+++ b/src/main.c
@@ -312,9 +312,7 @@ main (int argc, char *argv[])
 
 	nm_main_utils_ensure_rundir ();
 
-	/* check pid file */
-	if (nm_main_utils_check_pidfile (global_opt.pidfile, "NetworkManager"))
-		exit (1);
+	nm_main_utils_ensure_not_running_pidfile (global_opt.pidfile);
 
 	/* Read the config file and CLI overrides */
 	config = nm_config_new (&error);
diff --git a/src/nm-iface-helper.c b/src/nm-iface-helper.c
index 0c39d8fa5b..74db5b0ec0 100644
--- a/src/nm-iface-helper.c
+++ b/src/nm-iface-helper.c
@@ -381,11 +381,7 @@ main (int argc, char *argv[])
 	nm_main_utils_ensure_rundir ();
 
 	pidfile = g_strdup_printf (NMIH_PID_FILE_FMT, ifindex);
-	g_assert (pidfile);
-
-	/* check pid file */
-	if (nm_main_utils_check_pidfile (pidfile, "nm-iface-helper"))
-		exit (1);
+	nm_main_utils_ensure_not_running_pidfile (pidfile);
 
 	if (global_opt.become_daemon && !global_opt.debug) {
 		if (daemon (0, 0) < 0) {