From addc21bdf6537068cb113fb4a79518566935b68e Mon Sep 17 00:00:00 2001
From: Joachim Nilsson <troglobit@gmail.com>
Date: Mon, 8 Aug 2016 19:06:35 +0200
Subject: [PATCH] UTMP: Set BOOT_TIME record and add shutdown

This patch adds support for initializing /var/run/utmp with the initial
reboot as well as a shutdown record in the UTMP db.

Also, the run level change now properly records ~ and ~~ as line and id,
respectively, and the kernel release and time of each UTMP record is now
set properly.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
---
 finit.c    |  6 +++++-
 sig.c      |  4 ++++
 utmp-api.c | 32 ++++++++++++++++++++++++++++++--
 utmp-api.h |  6 ++++--
 4 files changed, 43 insertions(+), 5 deletions(-)

diff --git a/finit.c b/finit.c
index 346744f4..fc48c7ab 100644
--- a/finit.c
+++ b/finit.c
@@ -42,8 +42,9 @@
 #include "plugin.h"
 #include "service.h"
 #include "sig.h"
-#include "tty.h"
 #include "sm.h"
+#include "tty.h"
+#include "utmp-api.h"
 
 int   debug     = 0;
 int   quiet     = QUIET_MODE;	/* Delayed disable of silent mode. */
@@ -269,6 +270,9 @@ int main(int argc, char* argv[])
 		mount("tmpfs", "/run", "tmpfs", MS_NODEV, "mode=0755,size=10%");
 	umask(022);
 
+	/* Set BOOT_TIME UTMP entry */
+	utmp_set_boot();
+
 	/*
 	 * Parse kernel parameters
 	 */
diff --git a/sig.c b/sig.c
index 01149183..3fa7efef 100644
--- a/sig.c
+++ b/sig.c
@@ -78,6 +78,7 @@
 #include "private.h"
 #include "sig.h"
 #include "service.h"
+#include "utmp-api.h"
 
 static int   stopped = 0;
 static uev_t sigterm_watcher, sigusr1_watcher, sigusr2_watcher;
@@ -105,6 +106,9 @@ void do_shutdown(shutop_t op)
 	/* Call all shutdown hooks before rebooting... */
 	plugin_run_hooks(HOOK_SHUTDOWN);
 
+	/* Update UTMP db */
+	utmp_set_halt();
+
 	/* Here is where we signal watchdogd to do a forced reset for us */
 	_d("Sending SIGTERM to all processes.");
 	kill(-1, SIGTERM);
diff --git a/utmp-api.c b/utmp-api.c
index 1b140df5..34956440 100644
--- a/utmp-api.c
+++ b/utmp-api.c
@@ -24,17 +24,35 @@
 #include <stdio.h>
 #include <time.h>
 #include <utmp.h>
+#include <sys/utsname.h>
 #include <lite/lite.h>
 
-int utmp_set(int type, int pid, char *user)
+int utmp_set(int type, int pid, char *user, char *line, char *id)
 {
 	int result;
 	struct utmp ut;
+	struct utsname uts;
+
+	switch (type) {
+	case RUN_LVL:
+	case BOOT_TIME:
+		line = "~";
+		id   = "~~";
+		break;
+
+	default:
+		break;
+	}
 
 	memset(&ut, 0, sizeof(ut));
 	ut.ut_type  = type;
 	ut.ut_pid   = pid;
 	strlcpy(ut.ut_user, user, sizeof(ut.ut_user));
+	strlcpy(ut.ut_line, line, sizeof(ut.ut_line));
+	strlcpy(ut.ut_id, id, sizeof(ut.ut_id));
+	if (!uname(&uts))
+		strncpy(ut.ut_host, uts.release, sizeof(ut.ut_host));
+	ut.ut_tv.tv_sec = time(NULL);
 
 	setutent();
 	result = pututline(&ut) ? 0 : 1;;
@@ -51,7 +69,17 @@ static int encode(int lvl)
 
 int utmp_set_runlevel(int pre, int now)
 {
-	return utmp_set(RUN_LVL, (encode(pre) << 8) | (encode(now) & 0xFF), "runlevel"); 
+	return utmp_set(RUN_LVL, (encode(pre) << 8) | (encode(now) & 0xFF), "runlevel", NULL, NULL);
+}
+
+int utmp_set_boot(void)
+{
+	return utmp_set(BOOT_TIME, 0, "reboot", NULL, NULL);
+}
+
+int utmp_set_halt(void)
+{
+	return utmp_set(RUN_LVL, 0, "shutdown", NULL, NULL);
 }
 
 int utmp_show(char *file)
diff --git a/utmp-api.h b/utmp-api.h
index 5df60503..8c819f32 100644
--- a/utmp-api.h
+++ b/utmp-api.h
@@ -21,9 +21,11 @@
  * THE SOFTWARE.
  */
 
-int utmp_set (int type, int pid, char *user);
+int utmp_set         (int type, int pid, char *user, char *line, char *id);
+int utmp_set_boot    (void);
+int utmp_set_halt    (void);
 int utmp_set_runlevel(int pre, int now);
-int utmp_show(char *file);
+int utmp_show        (char *file);
 
 /**
  * Local Variables: