add support for writing reboot and shutdown records to wtmp

src/includes/rc-wtmp.h

@@ -0,0 +1,26 @@
+/*
+ * rc-wtmp.h
+ * This is private to us and not for user consumption
+*/
+
+/*
+ * Copyright (c) 2017 The OpenRC Authors.
+ * See the Authors file at the top-level directory of this distribution and
+ * https://github.com/OpenRC/openrc/blob/master/AUTHORS
+ *
+ * This file is part of OpenRC. It is subject to the license terms in
+ * the LICENSE file found in the top-level directory of this
+ * distribution and at https://github.com/OpenRC/openrc/blob/master/LICENSE
+ * This file may not be copied, modified, propagated, or distributed
+ *    except according to the terms contained in the LICENSE file.
+ */
+
+#ifndef __RC_WTMP_H__
+#define __RC_WTMP_H__
+
+#include <utmp.h>
+
+void log_wtmp(const char *user, const char *id, pid_t pid, int type,
+		const char *line);
+
+#endif

src/rc/Makefile

@@ -14,7 +14,7 @@ SRCS+=		rc-selinux.c
 endif
 
 ifeq (${OS},Linux)
-SRCS+=		kill_all.c openrc-init.c openrc-shutdown.c
+SRCS+=		kill_all.c openrc-init.c openrc-shutdown.c rc-wtmp.c
 endif
 
 CLEANFILES=	version.h rc-selinux.o
@@ -111,7 +111,7 @@ veinfo vewarn vebegin veend vewend veindent veoutdent: do_e.o rc-misc.o
 fstabinfo: fstabinfo.o _usage.o rc-misc.o
 	${CC} ${LOCAL_CFLAGS} ${LOCAL_LDFLAGS} ${CFLAGS} ${LDFLAGS} -o $@ $^ ${LDADD}
 
-openrc-init: openrc-init.o
+openrc-init: openrc-init.o rc-wtmp.o
 	${CC} ${LOCAL_CFLAGS} ${LOCAL_LDFLAGS} ${CFLAGS} ${LDFLAGS} -o $@ $^ ${LDADD}
 
 is_newer_than: is_newer_than.o rc-misc.o
@@ -132,7 +132,7 @@ mountinfo: mountinfo.o _usage.o rc-misc.o
 openrc rc: rc.o rc-logger.o rc-misc.o rc-plugin.o _usage.o
 	${CC} ${LOCAL_CFLAGS} ${LOCAL_LDFLAGS} ${CFLAGS} ${LDFLAGS} -o $@ $^ ${LDADD}
 
-openrc-shutdown: openrc-shutdown.o _usage.o
+openrc-shutdown: openrc-shutdown.o _usage.o rc-wtmp.o
 	${CC} ${LOCAL_CFLAGS} ${LOCAL_LDFLAGS} ${CFLAGS} ${LDFLAGS} -o $@ $^ ${LDADD}
 
 openrc-run runscript: openrc-run.o _usage.o rc-misc.o rc-plugin.o

src/rc/openrc-init.c

@@ -32,6 +32,7 @@
 
 #include "helpers.h"
 #include "rc.h"
+#include "rc-wtmp.h"
 #include "version.h"
 
 static const char *rc_default_runlevel = "default";
@@ -82,6 +83,7 @@ static void init(const char *default_runlevel)
 	}
 	pid = do_openrc(runlevel);
 	waitpid(pid, NULL, 0);
+	log_wtmp("reboot", "~~", 0, RUN_LVL, "~~");
 }
 
 static void handle_reexec(char *my_name)

src/rc/openrc-shutdown.c

@@ -27,46 +27,63 @@
 #include <string.h>
 #include <unistd.h>
 #include <sys/types.h>
+#include <sys/utsname.h>
 
 #include "einfo.h"
 #include "rc.h"
 #include "helpers.h"
 #include "_usage.h"
+#include "rc-wtmp.h"
 
 const char *applet = NULL;
 const char *extraopts = NULL;
-const char *getoptstring = "dHkpRr" getoptstring_COMMON;
+const char *getoptstring = "dDHKpRrw" getoptstring_COMMON;
 const struct option longopts[] = {
-	{ "dry-run",        no_argument, NULL, 'd'},
+	{ "no-write",        no_argument, NULL, 'd'},
+	{ "dry-run",        no_argument, NULL, 'D'},
 	{ "halt",        no_argument, NULL, 'H'},
-	{ "kexec",        no_argument, NULL, 'k'},
+	{ "kexec",        no_argument, NULL, 'K'},
 	{ "poweroff",        no_argument, NULL, 'p'},
 	{ "reexec",        no_argument, NULL, 'R'},
 	{ "reboot",        no_argument, NULL, 'r'},
+	{ "write-only",        no_argument, NULL, 'w'},
 	longopts_COMMON
 };
 const char * const longopts_help[] = {
+	"do not write wtmp record",
 	"print actions instead of executing them",
 	"halt the system",
 	"reboot the system using kexec",
 	"power off the system",
 	"re-execute init (use after upgrading)",
 	"reboot the system",
+	"write wtmp boot record and exit",
 	longopts_help_COMMON
 };
 const char *usagestring = NULL;
 const char *exclusive = "Select one of "
 "--halt, --kexec, --poweroff, --reexec or --reboot";
 
-static void send_cmd(const char *cmd, bool dryrun)
+static bool do_dryrun = false;
+static bool do_halt = false;
+static bool do_kexec = false;
+static bool do_poweroff = false;
+static bool do_reboot = false;
+static bool do_reexec = false;
+static bool do_wtmp = true;
+static bool do_wtmp_only = false;
+
+static void send_cmd(const char *cmd)
 {
 	FILE *fifo;
  	size_t ignored;
 
-	if (dryrun) {
+	if (do_dryrun) {
 		einfo("Would send %s to init", cmd);
 		return;
 	}
+	if (do_wtmp && (do_halt || do_kexec || do_reboot || do_poweroff))
+		log_wtmp("shutdown", "~~", 0, RUN_LVL, "~~");
 	fifo = fopen(RC_INIT_FIFO, "w");
 	if (!fifo) {
 		perror("fopen");
@@ -83,26 +100,23 @@ int main(int argc, char **argv)
 {
 	int opt;
 	int cmd_count = 0;
-	bool do_dryrun = false;
-	bool do_halt = false;
-	bool do_kexec = false;
-	bool do_poweroff = false;
-	bool do_reboot = false;
-	bool do_reexec = false;
 
 	applet = basename_c(argv[0]);
 	while ((opt = getopt_long(argc, argv, getoptstring,
 		    longopts, (int *) 0)) != -1)
 	{
 		switch (opt) {
-		case 'd':
+			case 'd':
+				do_wtmp = false;
+				break;
+		case 'D':
 			do_dryrun = true;
 			break;
 		case 'H':
 			do_halt = true;
 			cmd_count++;
 			break;
-		case 'k':
+		case 'K':
 			do_kexec = true;
 			cmd_count++;
 			break;
@@ -118,26 +132,31 @@ int main(int argc, char **argv)
 			do_reboot = true;
 			cmd_count++;
 			break;
+		case 'w':
+			do_wtmp_only = true;
+			break;
 		case_RC_COMMON_GETOPT
 		}
 	}
-if (geteuid() != 0 && ! do_dryrun)
-	eerrorx("%s: you must be root\n", applet);
+	if (geteuid() != 0 && ! do_dryrun)
+		eerrorx("%s: you must be root\n", applet);
 	if (cmd_count > 1) {
 		eerror("%s: %s\n", applet, exclusive);
 		usage(EXIT_FAILURE);
 	}
 	if (do_halt)
-		send_cmd("halt", do_dryrun);
+		send_cmd("halt");
 	else if (do_kexec)
-		send_cmd("kexec", do_dryrun);
+		send_cmd("kexec");
 	else if (do_poweroff)
-		send_cmd("poweroff", do_dryrun);
+		send_cmd("poweroff");
 	else if (do_reboot)
-		send_cmd("reboot", do_dryrun);
+		send_cmd("reboot");
 	else if (do_reexec)
-		send_cmd("reexec", do_dryrun);
+		send_cmd("reexec");
+	else if (do_wtmp_only)
+		log_wtmp("shutdown", "~~", 0, RUN_LVL, "~~");
 	else
-		send_cmd("single", do_dryrun);
+		send_cmd("single");
 	return 0;
 }

src/rc/rc-wtmp.c

@@ -0,0 +1,50 @@
+/*
+ * rc-wtmp.c
+ * This file contains routines to deal with the wtmp file.
+ */
+
+/*
+ * Copyright 2017 The OpenRC Authors.
+ * See the Authors file at the top-level directory of this distribution and
+ * https://github.com/OpenRC/openrc/blob/master/AUTHORS
+ *
+ * This file is part of OpenRC. It is subject to the license terms in
+ * the LICENSE file found in the top-level directory of this
+ * distribution and at https://github.com/OpenRC/openrc/blob/master/LICENSE
+ * This file may not be copied, modified, propagated, or distributed
+ *    except according to the terms contained in the LICENSE file.
+ */
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/utsname.h>
+
+#include "rc-wtmp.h"
+
+void log_wtmp(const char *user, const char *id, pid_t pid, int type,
+		const char *line)
+{
+	struct timeval tv;
+	struct utmp utmp;
+	struct utsname uname_buf;
+
+	memset(&utmp, 0, sizeof(utmp));
+	gettimeofday(&tv, NULL);
+	utmp.ut_tv.tv_sec = tv.tv_sec;
+	utmp.ut_tv.tv_usec = tv.tv_usec;
+	utmp.ut_pid  = pid;
+	utmp.ut_type = type;
+	strncpy(utmp.ut_name, user, sizeof(utmp.ut_name));
+	strncpy(utmp.ut_id  , id  , sizeof(utmp.ut_id  ));
+	strncpy(utmp.ut_line, line, sizeof(utmp.ut_line));
+        
+        /* Put the OS version in place of the hostname */
+        if (uname(&uname_buf) == 0)
+		strncpy(utmp.ut_host, uname_buf.release, sizeof(utmp.ut_host));
+
+	updwtmp(WTMP_FILE, &utmp);
+}