Convert built-in watchdog to a standalone mini watchdogd

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

configure.ac

@@ -218,9 +218,11 @@ AM_CONDITIONAL(INETD,     [test "x$enable_inetd" = "xyes"])
 AM_CONDITIONAL(WATCHDOGD, [test "x$enable_watchdog" = "xyes"])
 
 # Override default libdir, used for plugins and rescue.conf
-#pkglibdir=$libdir/finit
-#AC_SUBST(pkglibdir)
-#AC_EXPAND_DIR(pkglibdir, "$libdir/finit")
+pkglibdir=$libdir/finit
+AC_SUBST(pkglibexecdir)
+AC_EXPAND_DIR(pkglibexecdir, "$libexecdir/finit")
+AC_DEFINE_UNQUOTED(FINIT_LIBPATH_, "$pkglibexecdir", [Finit libexec path])
+
 AC_EXPAND_DIR(plugin_path, "$libdir/finit/plugins")
 AC_SUBST(plugin_path)
 AC_DEFINE_UNQUOTED(PLUGIN_PATH, "$plugin_path", [Finit plugin path])

src/Makefile.am

@@ -10,6 +10,9 @@ endif
 
 bin_PROGRAMS       = logit
 sbin_PROGRAMS      = finit initctl reboot
+if WATCHDOGD
+pkglibexec_PROGRAMS = watchdogd
+endif
 
 logit_SOURCES      = logit.c
 logit_CFLAGS       = -W -Wall -Wextra -Wno-unused-parameter -std=gnu99
@@ -36,9 +39,6 @@ pkginclude_HEADERS = cond.h finit.h helpers.h inetd.h log.h plugin.h svc.h
 if INETD
 finit_SOURCES     += inetd.c	inetd.h
 endif
-if WATCHDOGD
-finit_SOURCES     += watchdog.c	watchdog.h
-endif
 
 finit_CFLAGS       = -W -Wall -Wextra -Wno-unused-parameter -std=gnu99
 finit_CFLAGS      += $(lite_CFLAGS) $(uev_CFLAGS)
@@ -63,6 +63,12 @@ reboot_LDADD       = $(lite_LIBS)
 INIT_LNKS          = telinit init
 REBOOT_LNKS        = 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)
 install-exec-hook:
 	@$(INSTALL_DATA) $(srcdir)/rescue.conf $(DESTDIR)$(pkglibdir)

src/finit.c

@@ -47,7 +47,6 @@
 #include "tty.h"
 #include "util.h"
 #include "utmp-api.h"
-#include "watchdog.h"
 
 int   wdogpid   = 0;		/* No watchdog by default */
 int   runlevel  = 0;		/* Bootstrap 'S' */
@@ -214,12 +213,18 @@ static void emergency_shell(void)
  */
 static void finalize(void)
 {
+	svc_t *svc;
+
 	/*
 	 * Run startup scripts in the runparts directory, if any.
 	 */
 	if (runparts && fisdir(runparts) && !rescue)
 		run_parts(runparts, NULL);
 
+	svc = svc_find(FINIT_LIBPATH_ "watchdogd", 1);
+	if (svc && !wdogpid)
+		wdogpid = svc->pid;
+
 	/*
 	 * Start all tasks/services in the configured runlevel
 	 */
@@ -412,9 +417,10 @@ int main(int argc, char* argv[])
 	}
 
 	/*
-	 * Start built-in watchdog as soon as possible, if enabled
+	 * Start bundled watchdogd as soon as possible, if enabled
 	 */
-	wdogpid = watchdog(argv[0]);
+	if (which(FINIT_LIBPATH_ "/watchdogd"))
+		service_register(SVC_TYPE_SERVICE, FINIT_LIBPATH_ "/watchdogd", global_rlimit, NULL);
 
 	/*
 	 * Mount filesystems

src/watchdog.c

@@ -21,12 +21,18 @@
  * SOFTWARE.
  */
 
+#include <config.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
 #include <signal.h>
+#include <syslog.h>
 #include <sys/ioctl.h>
 #include <linux/watchdog.h>
 
-#include "finit.h"
-#include "log.h"
 #include "watchdog.h"
 
 int running  = 1;
@@ -51,6 +57,9 @@ static int init(char *progname, char *devnode)
 	signal(SIGTERM, sighandler);
 	signal(SIGPWR,  sighandler);
 
+	openlog(&progname[1], LOG_CONS | LOG_PID, LOG_DAEMON);
+	syslog(LOG_INFO, "Finit v%s basic watchdogd starting ...", VERSION);
+
 	fd = open(devnode, O_WRONLY);
 	if (fd == -1)
 		return -1;
@@ -78,6 +87,7 @@ static int loop(int fd, int timeout)
 
 	/* External watchdogd wants to take over ... */
 	if (handover) {
+		syslog(LOG_INFO, "Handing over %s and exiting ...", WDT_DEVNODE);
 		ioctl(fd, WDIOC_KEEPALIVE, &dummy);
 		return !write(fd, "V", 1);
 	}
@@ -85,35 +95,30 @@ static int loop(int fd, int timeout)
 	return 0;
 }
 
-int watchdog(char *progname)
+int main(int argc, char *argv[])
 {
-	int pid;
+	int fd, ret;
 
-	pid = fork();
-	if (pid == 0) {
-		int fd, ret;
-
-		fd = init(progname, WDT_DEVNODE);
-		if (fd == -1) {
-			if (ENOENT != errno)
-				_pe("Failed connecting to watchdog %s", WDT_DEVNODE);
-			_exit(1);
-		}
-
-		ret = loop(fd, WDT_TIMEOUT);
-		while (!handover) {
-			/* Waiting for SIGTERM ... */
-			sleep(1);
-
-			/* Set lowest possible timeout on SIGTERM */
-			ioctl(fd, WDIOC_SETTIMEOUT, &shutdown);
-		}
-		close(fd);
-
-		_exit(ret);
+	fd = init(argv[0], WDT_DEVNODE);
+	if (fd == -1) {
+		if (ENOENT != errno)
+			syslog(LOG_CRIT, "Failed connecting to watchdog %s", WDT_DEVNODE);
+		return 1;
 	}
 
-	return pid;
+	ret = loop(fd, WDT_TIMEOUT);
+	while (!handover) {
+		syslog(LOG_ALERT, "System going down ...");
+
+		/* Waiting for SIGTERM ... */
+		sleep(1);
+
+		/* Set lowest possible timeout on SIGTERM */
+		ioctl(fd, WDIOC_SETTIMEOUT, &shutdown);
+	}
+	close(fd);
+
+	return ret;
 }
 
 /**