supervise-daemon: make the pidfile an implementation detail

The pidfile of the supervisor doesn't need to be adjustable by the
service script. It is only used so the supervisor can stop itself when
the --stop option is used.

man/supervise-daemon.8

@@ -36,8 +36,6 @@
 .Ar count
 .Fl N , -nicelevel
 .Ar level
-.Fl p , -pidfile
-.Ar pidfile
 .Fl P , -respawn-period
 .Ar seconds
 .Fl R , -retry
@@ -57,8 +55,6 @@
 .Nm
 .Fl K , -stop
 .Ar daemon
-.Fl p , -pidfile
-.Ar pidfile
 .Fl r , -chroot
 .Ar chrootpath
 .Sh DESCRIPTION
@@ -76,12 +72,6 @@ should not be the one the daemon writes.
 .Pp
 Here are the options to specify the daemon and how it should start or stop:
 .Bl -tag -width indent
-.It Fl p , -pidfile Ar pidfile
-When starting, we write a
-.Ar pidfile
-so we know which supervisor to stop.  When stopping we only stop the pid(s)
-listed in the
-.Ar pidfile .
 .It Fl u , -user Ar user Ns Op : Ns Ar group
 Start the daemon as the
 .Ar user
@@ -132,7 +122,7 @@ signal/timeout pairs (like SIGTERM/5).
 If this option is not given, the default is SIGTERM/5.
 .It Fl r , -chroot Ar path
 chroot to this directory before starting the daemon. All other paths, such
-as the path to the daemon, chdir and pidfile, should be relative to the chroot.
+as the path to the daemon and chdir should be relative to the chroot.
 .It Fl u , -user Ar user
 Start the daemon as the specified user.
 .It Fl 1 , -stdout Ar logfile
@@ -145,7 +135,6 @@ The same thing as
 .Fl 1 , -stdout
 but with the standard error output.
 .El
-.El
 .Sh ENVIRONMENT
 .Va SSD_NICELEVEL
 can also set the scheduling priority of the daemon, but the command line
@@ -172,10 +161,6 @@ seconds.
 .Xr chroot 2 ,
 .Xr getopt 3 ,
 .Xr nice 2 ,
-.Xr rc_find_pids 3
-.Sh BUGS
-.Nm
-cannot stop an interpreted daemon that no longer exists without a pidfile.
 .Sh HISTORY
 .Nm
 first appeared in Debian.

sh/supervise-daemon.sh

@@ -30,7 +30,6 @@ supervise_start()
 		${chroot:+--chroot} $chroot \
 		${output_log+--stdout} ${output_log} \
 		${error_log+--stderr} $error_log \
-		${pidfile:+--pidfile} $pidfile \
 		${respawn_delay:+--respawn-delay} $respawn_delay \
 		${respawn_max:+--respawn-max} $respawn_max \
 		${respawn_period:+--respawn-period} $respawn_period \
@@ -44,21 +43,16 @@ supervise_start()
 	rc=$?
 	if [ $rc = 0 ]; then
 		[ -n "${chroot}" ] && service_set_value "chroot" "${chroot}"
-		[ -n "${pidfile}" ] && service_set_value "pidfile" "${pidfile}"
 	fi
 	eend $rc "failed to start ${name:-$RC_SVCNAME}"
 }
 
 supervise_stop()
 {
 	local startchroot="$(service_get_value "chroot")"
-	local startpidfile="$(service_get_value "pidfile")"
 	chroot="${startchroot:-$chroot}"
-	pidfile="${startpidfile:-$pidfile}"
-	[ -n "$pidfile" ] || return 0
 	ebegin "Stopping ${name:-$RC_SVCNAME}"
 	supervise-daemon "${RC_SVCNAME}" --stop \
-		${pidfile:+--pidfile} $chroot$pidfile \
 
 	eend $? "Failed to stop ${name:-$RC_SVCNAME}"
 }

src/rc/supervise-daemon.c

@@ -766,7 +766,7 @@ int main(int argc, char **argv)
 			break;
 
 		case 'p':  /* --pidfile <pid-file> */
-			pidfile = optarg;
+			ewarn("%s: --pidfile is deprecated and will be removed", applet);
 			break;
 
 		case 'R':  /* --retry <schedule>|timeout */
@@ -830,8 +830,6 @@ int main(int argc, char **argv)
 		case_RC_COMMON_GETOPT
 		}
 
-	if (!pidfile && !reexec)
-		eerrorx("%s: --pidfile must be specified", applet);
 	endpwent();
 	argc -= optind;
 	argv += optind;
@@ -844,6 +842,7 @@ int main(int argc, char **argv)
 		ch_root = expand_home(home, ch_root);
 
 	umask(numask);
+	xasprintf(&pidfile, "/var/run/supervise-%s.pid", svcname);
 
 	if (reexec) {
 		str = rc_service_value_get(svcname, "argc");
@@ -862,7 +861,6 @@ int main(int argc, char **argv)
 		sscanf(str, "%d", &child_pid);
 		free(str);
 		exec = rc_service_value_get(svcname, "exec");
-		pidfile = rc_service_value_get(svcname, "pidfile");
 		retry = rc_service_value_get(svcname, "retry");
 		if (retry) {
 			parse_schedule(applet, retry, sig);
@@ -944,7 +942,6 @@ int main(int argc, char **argv)
 			eerrorx("%s: fopen `%s': %s", applet, pidfile, strerror(errno));
 		fclose(fp);
 
-		rc_service_value_set(svcname, "pidfile", pidfile);
 		varbuf = NULL;
 		xasprintf(&varbuf, "%i", respawn_delay);
 		rc_service_value_set(svcname, "respawn_delay", varbuf);

supervise-daemon-guide.md

@@ -57,15 +57,6 @@ Several other variables affect the way services behave under
 supervise-daemon. They are documented on the  openrc-run man page, but I
 will list them here for convenience:
 
-``` sh
-pidfile=/pid/of/supervisor.pid
-```
-
-If you are using start-stop-daemon to monitor your scripts, the pidfile
-is the path to the pidfile the daemon creates. If, on the other hand,
-you are using supervise-daemon, this is the path to the pidfile the
-supervisor creates.
-
 ``` sh
 command_args_foreground="arguments"
 ```