add init process

openrc-init.c and openrc-shutdown.c are based on code which was written by
James Hammons <jlhamm@acm.org>, so I would like to publically
thank him for his work.

NEWS.md

@@ -3,6 +3,13 @@
 This file will contain a list of notable changes for each release. Note
 the information in this file is in reverse order.
 
+## OpenRC-0.25
+
+This version contains an OpenRC-specific implementation of init for
+Linux which can be used in place of sysvinit or any other init process.
+For information on its usage, see the man pages for openrc-init (8) and
+openrc-shutdown (8).
+
 ## OpenRC-0.24.1
 
 This version starts cleaning up the dependencies so that rc_parallel

etc/rc.conf

@@ -178,6 +178,11 @@
 # "xenU"           - XenU Domain (Linux and NetBSD)
 #rc_sys=""
 
+# if  you use openrc-init, which is currently only available on Linux,
+# this is the default runlevel to activate after "sysinit" and "boot"
+# when booting.
+#rc_default_runlevel="default"
+
 # on Linux and Hurd, this is the number of ttys allocated for logins
 # It is used in the consolefont, keymaps, numlock and termencoding
 # service scripts.

man/Makefile

@@ -9,7 +9,7 @@ MAN8=		rc-service.8 rc-status.8 rc-update.8 openrc.8 openrc-run.8 \
 		service.8 start-stop-daemon.8 supervise-daemon.8
 
 ifeq (${OS},Linux)
-MAN8 += rc-sstat.8
+MAN8 += rc-sstat.8 openrc-init.8 openrc-shutdown.8
 endif
 
 # Handy macro to create symlinks

man/openrc-init.8

@@ -0,0 +1,46 @@
+.\" 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.
+.\"
+.Dd April 6, 2017
+.Dt openrc-init 8 SMM
+.Os OpenRC
+.Sh NAME
+.Nm openrc-init
+.Nd the parent of all processes
+.Sh SYNOPSIS
+.Nm
+.Sh DESCRIPTION
+.Nm
+is an init process which can be an alternative to sysvinit or any other
+init process.
+.Pp
+To use
+.Nm
+configure your boot loader to invoke it or symlink it to /sbin/init.
+Also, you will need to use
+.Xr openrc-shutdown 8 ,
+to halt, reboot or poweroff the system.
+.Pp
+The default runlevel is read from the init command line, the
+rc_default_runlevel setting in rc.conf, the kernel command line, or it is
+assumed to be "default" if it is not set in any of these places.
+.Pp
+.Nm
+doesn't manage getty's directly, so you will need to manage them another
+way. For example, you can use the agetty service script as described in
+agetty-guide.md in this distribution.
+.Sh BUGS
+OpenRC 0.25 contains the first release of this init process.
+I do not know of any specific issues. However, if you use it, please be
+aware that there may be bugs and report any issues you find.
+.Sh SEE ALSO
+.Xr openrc-shutdown 8 ,
+.Sh AUTHORS
+.An William Hubbs <w.d.hubbs@gmail.com>

man/openrc-shutdown.8

@@ -0,0 +1,42 @@
+.\" 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.
+.\"
+.Dd April 6, 2017
+.Dt openrc-shutdown 8 SMM
+.Os OpenRC
+.Sh NAME
+.Nm openrc-shutdown
+.Nd bring the system down
+.Sh SYNOPSIS
+.Nm
+.Op Fl H , -halt
+.Op Fl k , -kexec
+.Op Fl p , -poweroff
+.Op Fl r , -reboot
+.Sh DESCRIPTION
+.Nm
+is the utility that communicates with openrc-init(8) to bring down the
+system.  The following options affect how the system is brought down:
+.Bl -tag -width "poweroff"
+.It Fl H , -halt
+Stop all services, kill all remaining processes and halt the system.
+.It Fl k , -kexec
+Stop all services, kill all processes and boot directly into a new
+kernel loaded via kexec(8).
+.It Fl p , -poweroff
+Stop all services, kill all processes and power off the system.
+.It Fl r , -reboot
+Stop all services, kill all processes and reboot the system.
+.El
+.Sh SEE ALSO
+.Xr openrc-init 8 ,
+.Xr kexec 8 ,
+.Sh AUTHORS
+.An William Hubbs <w.d.hubbs@gmail.com>

src/librc/rc.h.in

@@ -39,6 +39,7 @@ extern "C" {
 #define RC_CONFDIR              RC_SYSCONFDIR "/conf.d"
 #define RC_PLUGINDIR            RC_LIBDIR "/plugins"
 
+#define RC_INIT_FIFO RC_SVCDIR"/init.ctl"
 #define RC_PROFILE_ENV     RC_SYSCONFDIR "/profile.env"
 #define RC_SYS_WHITELIST   RC_LIBEXECDIR "/conf.d/env_whitelist"
 #define RC_USR_WHITELIST   RC_SYSCONFDIR "/conf.d/env_whitelist"

src/rc/.gitignore

@@ -59,4 +59,6 @@ mark_service_failed
 rc-abort
 rc
 openrc
+openrc-init
 openrc-run
+openrc-shutdown

src/rc/Makefile

@@ -1,3 +1,7 @@
+include ../../Makefile.inc
+MK=		../../mk
+include ${MK}/os.mk
+
 SRCS=	checkpath.c do_e.c do_mark_service.c do_service.c \
 		do_value.c fstabinfo.c is_newer_than.c is_older_than.c \
 		mountinfo.c openrc-run.c rc-abort.c rc.c \
@@ -9,6 +13,10 @@ ifeq (${MKSELINUX},yes)
 SRCS+=		rc-selinux.c
 endif
 
+ifeq (${OS},Linux)
+SRCS+=		openrc-init.c openrc-shutdown.c
+endif
+
 CLEANFILES=	version.h rc-selinux.o
 
 BINDIR=		${PREFIX}/bin
@@ -34,6 +42,11 @@ RC_SBINPROGS=	mark_service_starting mark_service_started \
 		mark_service_inactive mark_service_wasinactive \
 		mark_service_hotplugged mark_service_failed \
 		rc-abort swclock
+
+ifeq (${OS},Linux)
+SBINPROGS+= openrc-init openrc-shutdown
+endif
+
 ALL_PROGS=	${BINPROGS} ${SBINPROGS} ${RC_BINPROGS} ${RC_SBINPROGS}
 CLEANFILES+=	${ALL_PROGS}
 
@@ -41,8 +54,6 @@ LOCAL_CPPFLAGS=-I../includes -I../librc -I../libeinfo
 LOCAL_LDFLAGS=-L../librc -L../libeinfo
 LDADD+=		-lutil -lrc -leinfo
 
-include ../../Makefile.inc
-MK=		../../mk
 include ${MK}/prog.mk
 include ${MK}/gitver.mk
 include ${MK}/cc.mk
@@ -96,6 +107,9 @@ 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
+	${CC} ${LOCAL_CFLAGS} ${LOCAL_LDFLAGS} ${CFLAGS} ${LDFLAGS} -o $@ $^ ${LDADD}
+
 is_newer_than: is_newer_than.o rc-misc.o
 	${CC} ${LOCAL_CFLAGS} ${LOCAL_LDFLAGS} ${CFLAGS} ${LDFLAGS} -o $@ $^ ${LDADD}
 
@@ -114,6 +128,9 @@ 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
+	${CC} ${LOCAL_CFLAGS} ${LOCAL_LDFLAGS} ${CFLAGS} ${LDFLAGS} -o $@ $^ ${LDADD}
+
 openrc-run runscript: openrc-run.o _usage.o rc-misc.o rc-plugin.o
 ifeq (${MKSELINUX},yes)
 openrc-run runscript: rc-selinux.o

src/rc/openrc-init.c

@@ -0,0 +1,168 @@
+/*
+ * openrc-init.c
+ * This is the init process (pid 1) for OpenRC.
+ */
+
+/*
+ * 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.
+ */
+
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/reboot.h>
+#include <sys/wait.h>
+
+#include "helpers.h"
+#include "rc.h"
+#include "version.h"
+
+static const char *rc_default_runlevel = "default";
+
+static pid_t do_openrc(const char *runlevel)
+{
+	pid_t pid;
+
+	pid = fork();
+	switch(pid) {
+		case -1:
+			perror("fork");
+			break;
+		case 0:
+			setsid();
+			printf("Starting %s runlevel\n", runlevel);
+			execl("/sbin/openrc", "/sbin/openrc", runlevel, NULL);
+			perror("exec");
+			break;
+		default:
+			break;
+	}
+	return pid;
+}
+
+static void init(const char *default_runlevel)
+{
+	const char *runlevel = NULL;
+	pid_t pid;
+
+	pid = do_openrc("sysinit");
+	waitpid(pid, NULL, 0);
+	pid = do_openrc("boot");
+	waitpid(pid, NULL, 0);
+	if (default_runlevel)
+		runlevel = default_runlevel;
+	else
+		runlevel = rc_conf_value("rc_default_runlevel");
+	if (!runlevel)
+		runlevel = rc_default_runlevel;
+	if (!rc_runlevel_exists(runlevel)) {
+		printf("%s is an invalid runlevel\n", runlevel);
+		runlevel = rc_default_runlevel;
+	}
+	pid = do_openrc(runlevel);
+	waitpid(pid, NULL, 0);
+}
+
+static void handle_shutdown(const char *runlevel, int cmd)
+{
+	pid_t pid;
+
+	pid = do_openrc(runlevel);
+	while (waitpid(pid, NULL, 0) != pid);
+	sync();
+	reboot(cmd);
+}
+
+static void reap_zombies(void)
+{
+	pid_t pid;
+
+	for (;;) {
+		pid = waitpid(-1, NULL, WNOHANG);
+		if (pid == 0)
+			break;
+		else if (pid == -1) {
+			if (errno == ECHILD)
+				break;
+			perror("waitpid");
+			continue;
+		}
+	}
+}
+
+static void signal_handler(int sig)
+{
+	switch(sig) {
+		case SIGINT:
+			handle_shutdown("reboot", RB_AUTOBOOT);
+			break;
+		case SIGCHLD:
+			reap_zombies();
+			break;
+		default:
+			printf("Unknown signal received, %d\n", sig);
+			break;
+	}
+}
+
+int main(int argc, char **argv)
+{
+	char *default_runlevel = NULL;
+	char buf[2048];
+	int count;
+	FILE *fifo;
+	struct sigaction sa;
+
+	if (getpid() != 1)
+		return 1;
+
+	if (argc > 1)
+		default_runlevel = argv[1];
+
+	printf("OpenRC init version %s starting\n", VERSION);
+	init(default_runlevel);
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = signal_handler;
+	sigaction(SIGCHLD, &sa, NULL);
+	sigaction(SIGINT, &sa, NULL);
+	reboot(RB_DISABLE_CAD);
+
+	if (mkfifo(RC_INIT_FIFO, 0600) == -1)
+		perror("mkfifo");
+
+	for (;;) {
+		/* This will block until a command is sent down the pipe... */
+		fifo = fopen(RC_INIT_FIFO, "r");
+		if (!fifo) {
+			if (errno != EINTR)
+				perror("fopen");
+			continue;
+		}
+		count = fread(buf, 1, 2048, fifo);
+		buf[count] = 0;
+		fclose(fifo);
+		printf("PID1: Received \"%s\" from FIFO...\n", buf);
+		if (strcmp(buf, "halt") == 0)
+			handle_shutdown("shutdown", RB_HALT_SYSTEM);
+		else if (strcmp(buf, "kexec") == 0)
+			handle_shutdown("reboot", RB_KEXEC);
+		else if (strcmp(buf, "poweroff") == 0)
+			handle_shutdown("shutdown", RB_POWER_OFF);
+		else if (strcmp(buf, "reboot") == 0)
+			handle_shutdown("reboot", RB_AUTOBOOT);
+	}
+	return 0;
+}

src/rc/openrc-shutdown.c

@@ -0,0 +1,119 @@
+/*
+ * openrc-shutdown.c
+ * If you are using OpenRC's provided init, this will shut down or
+ * reboot your system.
+ */
+
+/*
+ * 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 <getopt.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+
+#include "einfo.h"
+#include "rc.h"
+#include "helpers.h"
+#include "_usage.h"
+
+const char *applet = NULL;
+const char *extraopts = NULL;
+const char *getoptstring = "kpr" getoptstring_COMMON;
+const struct option longopts[] = {
+	{ "halt",        no_argument, NULL, 'H'},
+	{ "kexec",        no_argument, NULL, 'k'},
+	{ "poweroff",        no_argument, NULL, 'p'},
+	{ "reboot",        no_argument, NULL, 'r'},
+	longopts_COMMON
+};
+const char * const longopts_help[] = {
+	"halt the system",
+	"reboot the system using kexec",
+	"power off the system",
+	"reboot the system",
+	longopts_help_COMMON
+};
+const char *usagestring = NULL;
+const char *exclusive = "Select one of --halt, --kexec, --poweroff or --reboot";
+
+static void send_cmd(const char *cmd)
+{
+	FILE *fifo;
+ 	size_t ignored;
+
+	fifo = fopen(RC_INIT_FIFO, "w");
+
+	if (!fifo) {
+		perror("fopen");
+		return;
+	}
+
+	ignored = fwrite(cmd, 1, strlen(cmd), fifo);
+	if (ignored != strlen(cmd))
+		printf("Error writing to init fifo\n");
+	fclose(fifo);
+}
+
+int main(int argc, char **argv)
+{
+	int opt;
+	int cmd_count = 0;
+	bool do_halt = false;
+	bool do_kexec = false;
+	bool do_poweroff = false;
+	bool do_reboot = false;
+
+	applet = basename_c(argv[0]);
+if (geteuid() != 0)
+	eerrorx("%s: you must be root\n", applet);
+	while ((opt = getopt_long(argc, argv, getoptstring,
+		    longopts, (int *) 0)) != -1)
+	{
+		switch (opt) {
+		case 'H':
+			do_halt = true;
+			cmd_count++;
+			break;
+		case 'k':
+			do_kexec = true;
+			cmd_count++;
+			break;
+		case 'p':
+			do_poweroff = true;
+			cmd_count++;
+			break;
+		case 'r':
+			do_reboot = true;
+			cmd_count++;
+			break;
+		case_RC_COMMON_GETOPT
+		}
+	}
+	if (cmd_count != 1) {
+		eerror("%s: %s\n", applet, exclusive);
+		usage(EXIT_FAILURE);
+	}
+	if (do_halt)
+		send_cmd("halt");
+	else if (do_kexec)
+		send_cmd("kexec");
+	else if (do_poweroff)
+		send_cmd("poweroff");
+	else if (do_reboot)
+		send_cmd("reboot");
+	return 0;
+}