Follow-up to 18ab7d3: restore start of built-in watchdogd

This patch restores the start of the built-in/bundled watchdogd.  It is
tracked in the `wdog` variable and handled as an exception at shutdown.

This is also a follow-up to 7b74c99, ensuring that we only kill/stop the
built-in watchdog, not any external.  External ones can register to be
the controlling watchdogd in the system -- Finit is not the arbiter for
singletons, this is up to the system engineer.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

src/Makefile.am

@@ -7,21 +7,21 @@ else
 AM_LDFLAGS         = -export-dynamic
 endif
 
-sbin_PROGRAMS      = finit initctl
-
+sbin_PROGRAMS        = finit initctl
+pkglibexec_PROGRAMS  =
 finit_pkglibdir      = $(pkglibdir)
 finit_pkglib_SCRIPTS = rescue.conf sample.conf
 
 if WATCHDOGD
-pkglibexec_PROGRAMS = watchdogd
+pkglibexec_PROGRAMS += watchdogd
 endif
 
 if LOGIT
-pkglibexec_PROGRAMS = logit
-logit_SOURCES       = logit.c logrotate.c
-logit_CFLAGS        = -W -Wall -Wextra -Wno-unused-parameter -std=gnu99
-logit_CFLAGS       += $(lite_CFLAGS)
-logit_LDADD         = $(lite_LIBS)
+pkglibexec_PROGRAMS += logit
+logit_SOURCES        = logit.c logrotate.c
+logit_CFLAGS         = -W -Wall -Wextra -Wno-unused-parameter -std=gnu99
+logit_CFLAGS        += $(lite_CFLAGS)
+logit_LDADD          = $(lite_LIBS)
 endif
 
 finit_SOURCES      = api.c	cgroup.c	cgroup.h	\
@@ -71,7 +71,6 @@ REBOOT_LNKS        = reboot shutdown halt poweroff suspend
 if WATCHDOGD
 watchdogd_SOURCES  = watchdog.c watchdog.h
 watchdogd_CFLAGS   = -W -Wall -Wextra -Wno-unused-parameter -std=gnu99
-#log.c log.h
 endif
 
 # Hook in install to add finit and reboot symlink(s)

src/api.c

@@ -270,10 +270,10 @@ static void send_svc(int sd, svc_t *svc)
 
 static void api_cb(uev_t *w, void *arg, int events)
 {
-	int sd, lvl;
-	svc_t *svc;
 	static svc_t *iter = NULL;
 	struct init_request rq;
+	int sd, lvl;
+	svc_t *svc;
 
 	sd = accept(w->fd, NULL, NULL);
 	if (sd < 0) {
@@ -394,13 +394,17 @@ static void api_cb(uev_t *w, void *arg, int events)
 				break;
 			}
 
-			/* Disable and allow Finit to collect bundled watchdog */
-			if (wdog) {
-				logit(LOG_NOTICE, "Stopping and removing %s (PID:%d)", wdog->cmd, wdog->pid);
-				stop(wdog);
+			if (wdog && wdog != svc) {
+				char name[32];
+
+				svc_ident(svc, name, sizeof(name));
+				logit(LOG_NOTICE, "Handing over wdog ctrl from %s[%d] to %s[%d]",
+				      svc_ident(wdog, NULL, 0), wdog->pid, name, svc->pid);
+
 				if (wdog->protect) {
-					wdog->protect = 0;
-					wdog->runlevels = 0;
+					logit(LOG_NOTICE, "Stopping and deleting built-in watchdog.");
+					stop(wdog);
+					svc_del(wdog);
 				}
 			}
 			wdog = svc;

src/finit.c

@@ -549,6 +549,14 @@ int main(int argc, char *argv[])
 	 */
 	conf_init(&loop);
 
+	/*
+	 * Start built-in watchdogd as soon as possible, if enabled
+	 */
+	if (which(FINIT_LIBPATH_ "/watchdogd")) {
+		service_register(SVC_TYPE_SERVICE, "[123456789] name:watchdog :finit " FINIT_LIBPATH_ "/watchdogd -- Finit watchdog daemon", global_rlimit, NULL);
+		wdog = svc_find_by_nameid("watchdog", "finit");
+	}
+
 	/* Base FS up, enable standard SysV init signals */
 	sig_setup(&loop);
 

src/watchdog.h

@@ -26,12 +26,6 @@
 #define WDT_DEVNODE "/dev/watchdog"
 #define WDT_TIMEOUT 30
 
-#ifdef BUILTIN_WATCHDOG
-int     watchdog(char *progname);
-#else
-#define watchdog(progname) 0
-#endif /* BUILTIN_WATCHDOG */
-
 /**
  * Local Variables:
  *  indent-tabs-mode: t