CONFIG_PID_FILE_PATH: new configuration option for pidfile paths

We set a default path for the directory where pidfiles are create
when FEATURE_PIDFILE is selected.  The default has no effect on
applets which must specify a pidfile path on the command line to
run, and it can be overridden by applets which optionally allow
the user to specify the pidfile path.

We also add pidfile write/remove support for klogd, ntpd and watchdog.
For syslogd, we add a missing remove_pidfile() for better cleanup
on daemon exit.

Signed-off-by: Anthony G. Basile <blueness@gentoo.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

9 files changed, 30 insertions, 9 deletions

diff --git a/Config.in b/Config.in
index 17bdc895a..b3fd65bd9 100644
--- a/Config.in
+++ b/Config.in
@@ -310,7 +310,18 @@ config FEATURE_PIDFILE
         default y
         help
           This option makes some applets (e.g. crond, syslogd, inetd) write
-          a pidfile in /var/run. Some applications rely on them.
+          a pidfile at the configured PID_FILE_PATH.  It has no effect
+          on applets which require pidfiles to run.
+
+config PID_FILE_PATH
+        string "Path to directory for pidfile"
+        default "/var/run"
+        depends on FEATURE_PIDFILE
+        help
+          This is the default path where pidfiles are created.  Applets which
+          allow you to set the pidfile path on the command line will override
+          this value.  The option has no effect on applets that require you to
+          specify a pidfile path.
 
 config FEATURE_SUID
         bool "Support for SUID/SGID handling"
diff --git a/miscutils/crond.c b/miscutils/crond.c
index a0b73c774..582dc991a 100644
--- a/miscutils/crond.c
+++ b/miscutils/crond.c
@@ -885,7 +885,7 @@ int crond_main(int argc UNUSED_PARAM, char **argv)
         xsetenv("SHELL", DEFAULT_SHELL); /* once, for all future children */
         crondlog(LVL8 "crond (busybox "BB_VER") started, log level %d", G.log_level);
         rescan_crontab_dir();
-        write_pidfile("/var/run/crond.pid");
+        write_pidfile(CONFIG_PID_FILE_PATH "/crond.pid");
 
         /* Main loop */
         t2 = time(NULL);
diff --git a/miscutils/watchdog.c b/miscutils/watchdog.c
index ee28dc30d..d3a76edf0 100644
--- a/miscutils/watchdog.c
+++ b/miscutils/watchdog.c
@@ -31,6 +31,7 @@ static void watchdog_shutdown(int sig UNUSED_PARAM)
 {
         static const char V = 'V';
 
+        remove_pidfile(CONFIG_PID_FILE_PATH "/watchdog.pid");
         write(3, &V, 1);  /* Magic, see watchdog-api.txt in kernel */
         if (ENABLE_FEATURE_CLEAN_UP)
                 close(3);
@@ -95,6 +96,8 @@ int watchdog_main(int argc, char **argv)
                 stimer_duration, htimer_duration * 1000);
 #endif
 
+        write_pidfile(CONFIG_PID_FILE_PATH "/watchdog.pid");
+
         while (1) {
                 /*
                  * Make sure we clear the counter before sleeping,
diff --git a/networking/ifplugd.c b/networking/ifplugd.c
index 88bf448fa..86586f0fe 100644
--- a/networking/ifplugd.c
+++ b/networking/ifplugd.c
@@ -551,7 +551,7 @@ int ifplugd_main(int argc UNUSED_PARAM, char **argv)
         applet_name = xasprintf("ifplugd(%s)", G.iface);
 
 #if ENABLE_FEATURE_PIDFILE
-        pidfile_name = xasprintf(_PATH_VARRUN"ifplugd.%s.pid", G.iface);
+        pidfile_name = xasprintf(CONFIG_PID_FILE_PATH "/ifplugd.%s.pid", G.iface);
         pid_from_pidfile = read_pid(pidfile_name);
 
         if (opts & FLAG_KILL) {
diff --git a/networking/inetd.c b/networking/inetd.c
index 00baf6971..584c5e5e4 100644
--- a/networking/inetd.c
+++ b/networking/inetd.c
@@ -186,8 +186,6 @@
 #define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN 0
 #endif
 
-#define _PATH_INETDPID  "/var/run/inetd.pid"
-
 #define CNT_INTERVAL    60      /* servers in CNT_INTERVAL sec. */
 #define RETRYTIME       60      /* retry after bind or server fail */
 
@@ -1132,7 +1130,7 @@ static void clean_up_and_exit(int sig UNUSED_PARAM)
                 if (ENABLE_FEATURE_CLEAN_UP)
                         close(sep->se_fd);
         }
-        remove_pidfile(_PATH_INETDPID);
+        remove_pidfile(CONFIG_PID_FILE_PATH "/inetd.pid");
         exit(EXIT_SUCCESS);
 }
 
@@ -1181,7 +1179,7 @@ int inetd_main(int argc UNUSED_PARAM, char **argv)
                 setgroups(1, &gid);
         }
 
-        write_pidfile(_PATH_INETDPID);
+        write_pidfile(CONFIG_PID_FILE_PATH "/inetd.pid");
 
         /* never fails under Linux (except if you pass it bad arguments) */
         getrlimit(RLIMIT_NOFILE, &rlim_ofile);
diff --git a/networking/ntpd.c b/networking/ntpd.c
index 5b92db6f6..7facf9484 100644
--- a/networking/ntpd.c
+++ b/networking/ntpd.c
@@ -2080,6 +2080,8 @@ int ntpd_main(int argc UNUSED_PARAM, char **argv)
          */
         cnt = G.peer_cnt * (INITIAL_SAMPLES + 1);
 
+        write_pidfile(CONFIG_PID_FILE_PATH "/ntpd.pid");
+
         while (!bb_got_signal) {
                 llist_t *item;
                 unsigned i, j;
@@ -2195,6 +2197,7 @@ int ntpd_main(int argc UNUSED_PARAM, char **argv)
                 }
         } /* while (!bb_got_signal) */
 
+        remove_pidfile(CONFIG_PID_FILE_PATH "/ntpd.pid");
         kill_myself_with_sig(bb_got_signal);
 }
 
diff --git a/sysklogd/klogd.c b/sysklogd/klogd.c
index efa0e537a..f59a155b4 100644
--- a/sysklogd/klogd.c
+++ b/sysklogd/klogd.c
@@ -195,6 +195,8 @@ int klogd_main(int argc UNUSED_PARAM, char **argv)
 
         syslog(LOG_NOTICE, "klogd started: %s", bb_banner);
 
+        write_pidfile(CONFIG_PID_FILE_PATH "/klogd.pid");
+
         used = 0;
         while (!bb_got_signal) {
                 int n;
@@ -258,6 +260,7 @@ int klogd_main(int argc UNUSED_PARAM, char **argv)
 
         klogd_close();
         syslog(LOG_NOTICE, "klogd: exiting");
+        remove_pidfile(CONFIG_PID_FILE_PATH "/klogd.pid");
         if (bb_got_signal)
                 kill_myself_with_sig(bb_got_signal);
         return EXIT_FAILURE;
diff --git a/sysklogd/syslogd.c b/sysklogd/syslogd.c
index fc380d9f9..5854bcd0f 100644
--- a/sysklogd/syslogd.c
+++ b/sysklogd/syslogd.c
@@ -916,6 +916,7 @@ static void do_syslogd(void)
 
         timestamp_and_log_internal("syslogd exiting");
         puts("syslogd exiting");
+        remove_pidfile(CONFIG_PID_FILE_PATH "/syslogd.pid");
         if (ENABLE_FEATURE_IPC_SYSLOG)
                 ipcsyslog_cleanup();
         kill_myself_with_sig(bb_got_signal);
@@ -979,8 +980,10 @@ int syslogd_main(int argc UNUSED_PARAM, char **argv)
         if (!(opts & OPT_nofork)) {
                 bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);
         }
+
         //umask(0); - why??
-        write_pidfile("/var/run/syslogd.pid");
+        write_pidfile(CONFIG_PID_FILE_PATH "/syslogd.pid");
+
         do_syslogd();
         /* return EXIT_SUCCESS; */
 }
diff --git a/util-linux/acpid.c b/util-linux/acpid.c
index 5d2792948..38421c2d7 100644
--- a/util-linux/acpid.c
+++ b/util-linux/acpid.c
@@ -235,7 +235,7 @@ int acpid_main(int argc UNUSED_PARAM, char **argv)
         const char *opt_action = "/etc/acpid.conf";
         const char *opt_map = "/etc/acpi.map";
 #if ENABLE_FEATURE_PIDFILE
-        const char *opt_pidfile = "/var/run/acpid.pid";
+        const char *opt_pidfile = CONFIG_PID_FILE_PATH "/acpid.pid";
 #endif
 
         INIT_G();