[thirdparty/systemd.git] / main.c

/*-*- Mode: C; c-basic-offset: 8 -*-*/

/***
  This file is part of systemd.

  Copyright 2010 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  systemd is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include <dbus/dbus.h>

#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <getopt.h>
#include <signal.h>
#include <sys/wait.h>
#include <fcntl.h>

#include "manager.h"
#include "log.h"
#include "mount-setup.h"
#include "hostname-setup.h"
#include "load-fragment.h"

static enum {
        ACTION_RUN,
        ACTION_HELP,
        ACTION_TEST,
        ACTION_DUMP_CONFIGURATION_ITEMS
} action = ACTION_RUN;

static char *default_unit = NULL;
static ManagerRunningAs running_as = _MANAGER_RUNNING_AS_INVALID;

static bool dump_core = true;
static bool crash_shell = false;
static int crash_chvt = -1;

static bool confirm_spawn = false;

_noreturn static void freeze(void) {
        for (;;)
                pause();
}

static void nop_handler(int sig) {
}

_noreturn static void crash(int sig) {

        if (!dump_core)
                log_error("Caught <%s>, not dumping core.", strsignal(sig));
        else {
                struct sigaction sa;
                pid_t pid;

                /* We want to wait for the core process, hence let's enable SIGCHLD */
                zero(sa);
                sa.sa_handler = nop_handler;
                sa.sa_flags = SA_NOCLDSTOP|SA_RESTART;
                assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);

                if ((pid = fork()) < 0)
                        log_error("Caught <%s>, cannot fork for core dump: %s", strsignal(sig), strerror(errno));

                else if (pid == 0) {
                        struct rlimit rl;

                        /* Enable default signal handler for core dump */
                        zero(sa);
                        sa.sa_handler = SIG_DFL;
                        assert_se(sigaction(sig, &sa, NULL) == 0);

                        /* Don't limit the core dump size */
                        zero(rl);
                        rl.rlim_cur = RLIM_INFINITY;
                        rl.rlim_max = RLIM_INFINITY;
                        setrlimit(RLIMIT_CORE, &rl);

                        /* Just to be sure... */
                        assert_se(chdir("/") == 0);

                        /* Raise the signal again */
                        raise(sig);

                        assert_not_reached("We shouldn't be here...");
                        _exit(1);

                } else {
                        int status, r;

                        /* Order things nicely. */
                        if ((r = waitpid(pid, &status, 0)) < 0)
                                log_error("Caught <%s>, waitpid() failed: %s", strsignal(sig), strerror(errno));
                        else if (!WCOREDUMP(status))
                                log_error("Caught <%s>, core dump failed.", strsignal(sig));
                        else
                                log_error("Caught <%s>, dumped core as pid %llu.", strsignal(sig), (unsigned long long) pid);
                }
        }

        if (crash_chvt)
                chvt(crash_chvt);

        if (crash_shell) {
                struct sigaction sa;
                pid_t pid;

                log_info("Executing crash shell in 10s...");
                sleep(10);

                /* Let the kernel reap children for us */
                zero(sa);
                sa.sa_handler = SIG_IGN;
                sa.sa_flags = SA_NOCLDSTOP|SA_NOCLDWAIT|SA_RESTART;
                assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);

                if ((pid = fork()) < 0)
                        log_error("Failed to fork off crash shell: %s", strerror(errno));
                else if (pid == 0) {
                        execl("/bin/sh", "/bin/sh", NULL);

                        log_error("execl() failed: %s", strerror(errno));
                        _exit(1);
                }

                log_info("Successfully spawned crash shall as pid %llu.", (unsigned long long) pid);
        }

        log_info("Freezing execution.");
        freeze();
}

static void install_crash_handler(void) {
        struct sigaction sa;

        zero(sa);

        sa.sa_handler = crash;
        sa.sa_flags = SA_NODEFER;

        assert_se(sigaction(SIGSEGV, &sa, NULL) == 0);
        assert_se(sigaction(SIGILL, &sa, NULL) == 0);
        assert_se(sigaction(SIGFPE, &sa, NULL) == 0);
        assert_se(sigaction(SIGBUS, &sa, NULL) == 0);
        assert_se(sigaction(SIGQUIT, &sa, NULL) == 0);
        assert_se(sigaction(SIGABRT, &sa, NULL) == 0);
}

static int console_setup(void) {
        int tty_fd = -1, null_fd = -1, r = 0;

        /* If we are init, we connect stdout/stderr to /dev/console
         * and stdin to /dev/null and make sure we don't have a
         * controlling tty. */

        release_terminal();

        if ((tty_fd = open_terminal("/dev/console", O_WRONLY)) < 0) {
                log_error("Failed to open /dev/console: %s", strerror(-tty_fd));
                r = -tty_fd;
                goto finish;
        }

        if ((null_fd = open("/dev/null", O_RDONLY)) < 0) {
                log_error("Failed to open /dev/null: %m");
                r = -errno;
                goto finish;
        }

        assert(tty_fd >= 3);
        assert(null_fd >= 3);

        if (reset_terminal(tty_fd) < 0)
                log_error("Failed to reset /dev/console: %m");

        if (dup2(tty_fd, STDOUT_FILENO) < 0 ||
            dup2(tty_fd, STDERR_FILENO) < 0 ||
            dup2(null_fd, STDIN_FILENO) < 0) {
                log_error("Failed to dup2() device: %m");
                r = -errno;
                goto finish;
        }

        r = 0;

finish:
        if (tty_fd >= 0)
                close_nointr(tty_fd);

        if (null_fd >= 0)
                close_nointr(null_fd);

        return r;
}

static int set_default_unit(const char *u) {
        char *c;

        assert(u);

        if (!(c = strdup(u)))
                return -ENOMEM;

        free(default_unit);
        default_unit = c;
        return 0;
}

static int parse_proc_cmdline_word(const char *word) {

        static const char * const rlmap[] = {
                "single", SPECIAL_RUNLEVEL1_TARGET,
                "-s",     SPECIAL_RUNLEVEL1_TARGET,
                "s",      SPECIAL_RUNLEVEL1_TARGET,
                "S",      SPECIAL_RUNLEVEL1_TARGET,
                "1",      SPECIAL_RUNLEVEL1_TARGET,
                "2",      SPECIAL_RUNLEVEL2_TARGET,
                "3",      SPECIAL_RUNLEVEL3_TARGET,
                "4",      SPECIAL_RUNLEVEL4_TARGET,
                "5",      SPECIAL_RUNLEVEL5_TARGET
        };

        if (startswith(word, "systemd.default="))
                return set_default_unit(word + 16);

        else if (startswith(word, "systemd.log_target=")) {

                if (log_set_target_from_string(word + 19) < 0)
                        log_warning("Failed to parse log target %s. Ignoring.", word + 19);

        } else if (startswith(word, "systemd.log_level=")) {

                if (log_set_max_level_from_string(word + 18) < 0)
                        log_warning("Failed to parse log level %s. Ignoring.", word + 18);

        } else if (startswith(word, "systemd.dump_core=")) {
                int r;

                if ((r = parse_boolean(word + 18)) < 0)
                        log_warning("Failed to parse dump core switch %s, Ignoring.", word + 18);
                else
                        dump_core = r;

        } else if (startswith(word, "systemd.crash_shell=")) {
                int r;

                if ((r = parse_boolean(word + 20)) < 0)
                        log_warning("Failed to parse crash shell switch %s, Ignoring.", word + 20);
                else
                        crash_shell = r;


        } else if (startswith(word, "systemd.confirm_spawn=")) {
                int r;

                if ((r = parse_boolean(word + 22)) < 0)
                        log_warning("Failed to parse confirm spawn switch %s, Ignoring.", word + 22);
                else
                        confirm_spawn = r;

        } else if (startswith(word, "systemd.crash_chvt=")) {
                int k;

                if (safe_atoi(word + 19, &k) < 0)
                        log_warning("Failed to parse crash chvt switch %s, Ignoring.", word + 19);
                else
                        crash_chvt = k;

        } else if (startswith(word, "systemd.")) {

                log_warning("Unknown kernel switch %s. Ignoring.", word);

                log_info("Supported kernel switches:");
                log_info("systemd.default=UNIT                     Default unit to start");
                log_info("systemd.log_target=console|kmsg|syslog   Log target");
                log_info("systemd.log_level=LEVEL                  Log level");
                log_info("systemd.dump_core=0|1                    Dump core on crash");
                log_info("systemd.crash_shell=0|1                  On crash run shell");
                log_info("systemd.crash_chvt=N                     Change to VT #N on crash");
                log_info("systemd.confirm_spawn=0|1                Confirm every process spawn");

        } else {
                unsigned i;

                /* SysV compatibility */
                for (i = 0; i < ELEMENTSOF(rlmap); i += 2)
                        if (streq(word, rlmap[i]))
                                return set_default_unit(rlmap[i+1]);
        }

        return 0;
}

static int parse_proc_cmdline(void) {
        char *line;
        int r;
        char *w;
        size_t l;
        char *state;

        if ((r = read_one_line_file("/proc/cmdline", &line)) < 0) {
                log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(errno));
                return 0;
        }

        FOREACH_WORD_QUOTED(w, l, line, state) {
                char *word;

                if (!(word = strndup(w, l))) {
                        r = -ENOMEM;
                        goto finish;
                }

                r = parse_proc_cmdline_word(word);
                free(word);

                if (r < 0)
                        goto finish;
        }

        r = 0;

finish:
        free(line);
        return r;
}

static int parse_argv(int argc, char *argv[]) {

        enum {
                ARG_LOG_LEVEL = 0x100,
                ARG_LOG_TARGET,
                ARG_DEFAULT,
                ARG_RUNNING_AS,
                ARG_TEST,
                ARG_DUMP_CONFIGURATION_ITEMS,
                ARG_CONFIRM_SPAWN
        };

        static const struct option options[] = {
                { "log-level",  required_argument, NULL, ARG_LOG_LEVEL },
                { "log-target", required_argument, NULL, ARG_LOG_TARGET },
                { "default",    required_argument, NULL, ARG_DEFAULT },
                { "running-as", required_argument, NULL, ARG_RUNNING_AS },
                { "test",       no_argument,       NULL, ARG_TEST },
                { "help",       no_argument,       NULL, 'h' },
                { "dump-configuration-items", no_argument, NULL, ARG_DUMP_CONFIGURATION_ITEMS },
                { "confirm-spawn", no_argument,    NULL, ARG_CONFIRM_SPAWN },
                { NULL,         0,                 NULL, 0 }
        };

        int c, r;

        assert(argc >= 1);
        assert(argv);

        while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)

                switch (c) {

                case ARG_LOG_LEVEL:
                        if ((r = log_set_max_level_from_string(optarg)) < 0) {
                                log_error("Failed to parse log level %s.", optarg);
                                return r;
                        }

                        break;

                case ARG_LOG_TARGET:

                        if ((r = log_set_target_from_string(optarg)) < 0) {
                                log_error("Failed to parse log target %s.", optarg);
                                return r;
                        }

                        break;

                case ARG_DEFAULT:

                        if ((r = set_default_unit(optarg)) < 0) {
                                log_error("Failed to set default unit %s: %s", optarg, strerror(-r));
                                return r;
                        }

                        break;

                case ARG_RUNNING_AS: {
                        ManagerRunningAs as;

                        if ((as = manager_running_as_from_string(optarg)) < 0) {
                                log_error("Failed to parse running as value %s", optarg);
                                return -EINVAL;
                        }

                        running_as = as;
                        break;
                }

                case ARG_TEST:
                        action = ACTION_TEST;
                        break;

                case ARG_DUMP_CONFIGURATION_ITEMS:
                        action = ACTION_DUMP_CONFIGURATION_ITEMS;
                        break;

                case ARG_CONFIRM_SPAWN:
                        confirm_spawn = true;
                        break;

                case 'h':
                        action = ACTION_HELP;
                        break;

                case '?':
                        return -EINVAL;

                default:
                        log_error("Unknown option code %c", c);
                        return -EINVAL;
                }

        return 0;
}

static int help(void) {

        printf("%s [options]\n\n"
               "  -h --help                      Show this help\n"
               "     --default=UNIT              Set default unit\n"
               "     --log-level=LEVEL           Set log level\n"
               "     --log-target=TARGET         Set log target (console, syslog, kmsg)\n"
               "     --running-as=AS             Set running as (init, system, session)\n"
               "     --test                      Determine startup sequence, dump it and exit\n"
               "     --dump-configuration-items  Dump understood unit configuration items\n"
               "     --confirm-spawn             Ask for confirmation when spawning processes\n",
               __progname);

        return 0;
}

int main(int argc, char *argv[]) {
        Manager *m = NULL;
        Unit *target = NULL;
        Job *job = NULL;
        int r, retval = 1;

        if (getpid() == 1)
                running_as = MANAGER_INIT;
        else if (getuid() == 0)
                running_as = MANAGER_SYSTEM;
        else
                running_as = MANAGER_SESSION;

        if (set_default_unit(SPECIAL_DEFAULT_TARGET) < 0)
                goto finish;

        /* Mount /proc, /sys and friends, so that /proc/cmdline and
         * /proc/$PID/fd is available. */
        if (mount_setup() < 0)
                goto finish;

        /* Reset all signal handlers. */
        assert_se(reset_all_signal_handlers() == 0);

        /* If we are init, we can block sigkill. Yay. */
        ignore_signal(SIGKILL);
        ignore_signal(SIGPIPE);

        /* Close all open files */
        assert_se(close_all_fds(NULL, 0) == 0);

        if (running_as != MANAGER_SESSION)
                if (parse_proc_cmdline() < 0)
                        goto finish;

        log_parse_environment();

        if (parse_argv(argc, argv) < 0)
                goto finish;

        if (action == ACTION_HELP) {
                retval = help();
                goto finish;
        } else if (action == ACTION_DUMP_CONFIGURATION_ITEMS) {
                unit_dump_config_items(stdout);
                retval = 0;
                goto finish;
        }

        assert_se(action == ACTION_RUN || action == ACTION_TEST);

        /* Set up PATH unless it is already set */
        setenv("PATH",
               "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
               running_as == MANAGER_INIT);

        /* Move out of the way, so that we won't block unmounts */
        assert_se(chdir("/")  == 0);

        if (running_as != MANAGER_SESSION) {
                /* Become a session leader if we aren't one yet. */
                setsid();

                /* Disable the umask logic */
                umask(0);
        }

        if (running_as == MANAGER_INIT)
                console_setup();

        /* Make sure D-Bus doesn't fiddle with the SIGPIPE handlers */
        dbus_connection_set_change_sigpipe(FALSE);

        /* Open the logging devices, if possible and necessary */
        log_open_syslog();
        log_open_kmsg();

        /* Make sure we leave a core dump without panicing the
         * kernel. */
        if (getpid() == 1)
                install_crash_handler();

        log_debug("systemd running in %s mode.", manager_running_as_to_string(running_as));

        if (running_as == MANAGER_INIT)
                hostname_setup();

        if ((r = manager_new(running_as, confirm_spawn, &m)) < 0) {
                log_error("Failed to allocate manager object: %s", strerror(-r));
                goto finish;
        }

        if ((r = manager_coldplug(m)) < 0) {
                log_error("Failed to retrieve coldplug information: %s", strerror(-r));
                goto finish;
        }

        log_debug("Activating default unit: %s", default_unit);

        if ((r = manager_load_unit(m, default_unit, NULL, &target)) < 0) {
                log_error("Failed to load default target: %s", strerror(-r));

                log_info("Trying to load rescue target...");
                if ((r = manager_load_unit(m, SPECIAL_RESCUE_TARGET, NULL, &target)) < 0) {
                        log_error("Failed to load rescue target: %s", strerror(-r));
                        goto finish;
                }
        }

        if (action == ACTION_TEST) {
                printf("→ By units:\n");
                manager_dump_units(m, stdout, "\t");
        }

        if ((r = manager_add_job(m, JOB_START, target, JOB_REPLACE, false, &job)) < 0) {
                log_error("Failed to start default target: %s", strerror(-r));
                goto finish;
        }

        if (action == ACTION_TEST) {
                printf("→ By jobs:\n");
                manager_dump_jobs(m, stdout, "\t");

                if (getpid() == 1)
                        pause();

                retval = 0;
                goto finish;
        }

        if ((r = manager_loop(m)) < 0) {
                log_error("Failed to run mainloop: %s", strerror(-r));
                goto finish;
        }

        retval = 0;

        log_debug("Exit.");

finish:
        if (m)
                manager_free(m);

        free(default_unit);

        dbus_shutdown();

        if (getpid() == 1)
                freeze();

        return retval;
}
Commit	Line	Data
60918275 LP	1	/-- Mode: C; c-basic-offset: 8 --/
60918275 LP	2
a7334b09 LP	3	/***
	4	This file is part of systemd.
	5
	6	Copyright 2010 Lennart Poettering
	7
	8	systemd is free software; you can redistribute it and/or modify it
	9	under the terms of the GNU General Public License as published by
	10	the Free Software Foundation; either version 2 of the License, or
	11	(at your option) any later version.
	12
	13	systemd is distributed in the hope that it will be useful, but
	14	WITHOUT ANY WARRANTY; without even the implied warranty of
	15	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	16	General Public License for more details.
	17
	18	You should have received a copy of the GNU General Public License
	19	along with systemd; If not, see <http://www.gnu.org/licenses/>.
	20	***/
	21
ea430986 LP	22	#include <dbus/dbus.h>
ea430986 LP	23
60918275 LP	24	#include <stdio.h>
	25	#include <errno.h>
	26	#include <string.h>
16354eff	27	#include <unistd.h>
4ade7963 LP	28	#include <sys/types.h>
4ade7963 LP	29	#include <sys/stat.h>
f170852a	30	#include <getopt.h>
97c4f35c	31	#include <signal.h>
4fc935ca	32	#include <sys/wait.h>
80876c20	33	#include <fcntl.h>
60918275 LP	34
60918275 LP	35	#include "manager.h"
16354eff	36	#include "log.h"
4ade7963	37	#include "mount-setup.h"
302e8c4c LP	38	#include "hostname-setup.h"
302e8c4c LP	39	#include "load-fragment.h"
60918275	40
f170852a LP	41	static enum {
f170852a LP	42	ACTION_RUN,
e965d56d	43	ACTION_HELP,
e537352b LP	44	ACTION_TEST,
e537352b LP	45	ACTION_DUMP_CONFIGURATION_ITEMS
f170852a LP	46	} action = ACTION_RUN;
	47
	48	static char *default_unit = NULL;
a5dab5ce	49	static ManagerRunningAs running_as = _MANAGER_RUNNING_AS_INVALID;
4fc935ca	50
97c4f35c	51	static bool dump_core = true;
601f6a1e LP	52	static bool crash_shell = false;
601f6a1e LP	53	static int crash_chvt = -1;
97c4f35c	54
80876c20 LP	55	static bool confirm_spawn = false;
80876c20 LP	56
97c4f35c LP	57	_noreturn static void freeze(void) {
	58	for (;;)
	59	pause();
	60	}
	61
6f5e3f35 LP	62	static void nop_handler(int sig) {
	63	}
	64
97c4f35c LP	65	_noreturn static void crash(int sig) {
	66
	67	if (!dump_core)
	68	log_error("Caught <%s>, not dumping core.", strsignal(sig));
	69	else {
6f5e3f35	70	struct sigaction sa;
97c4f35c LP	71	pid_t pid;
97c4f35c LP	72
6f5e3f35 LP	73	/* We want to wait for the core process, hence let's enable SIGCHLD */
	74	zero(sa);
	75	sa.sa_handler = nop_handler;
	76	sa.sa_flags = SA_NOCLDSTOP\|SA_RESTART;
	77	assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);
	78
97c4f35c	79	if ((pid = fork()) < 0)
4fc935ca	80	log_error("Caught <%s>, cannot fork for core dump: %s", strsignal(sig), strerror(errno));
97c4f35c LP	81
97c4f35c LP	82	else if (pid == 0) {
97c4f35c LP	83	struct rlimit rl;
	84
	85	/* Enable default signal handler for core dump */
	86	zero(sa);
	87	sa.sa_handler = SIG_DFL;
	88	assert_se(sigaction(sig, &sa, NULL) == 0);
	89
	90	/* Don't limit the core dump size */
	91	zero(rl);
	92	rl.rlim_cur = RLIM_INFINITY;
	93	rl.rlim_max = RLIM_INFINITY;
	94	setrlimit(RLIMIT_CORE, &rl);
	95
	96	/* Just to be sure... */
	97	assert_se(chdir("/") == 0);
	98
	99	/* Raise the signal again */
	100	raise(sig);
	101
	102	assert_not_reached("We shouldn't be here...");
	103	_exit(1);
4fc935ca LP	104
	105	} else {
	106	int status, r;
	107
	108	/* Order things nicely. */
	109	if ((r = waitpid(pid, &status, 0)) < 0)
	110	log_error("Caught <%s>, waitpid() failed: %s", strsignal(sig), strerror(errno));
	111	else if (!WCOREDUMP(status))
	112	log_error("Caught <%s>, core dump failed.", strsignal(sig));
	113	else
	114	log_error("Caught <%s>, dumped core as pid %llu.", strsignal(sig), (unsigned long long) pid);
97c4f35c LP	115	}
	116	}
	117
601f6a1e LP	118	if (crash_chvt)
	119	chvt(crash_chvt);
	120
4fc935ca	121	if (crash_shell) {
6f5e3f35 LP	122	struct sigaction sa;
6f5e3f35 LP	123	pid_t pid;
8c43883a	124
4fc935ca LP	125	log_info("Executing crash shell in 10s...");
	126	sleep(10);
	127
6f5e3f35 LP	128	/* Let the kernel reap children for us */
	129	zero(sa);
	130	sa.sa_handler = SIG_IGN;
	131	sa.sa_flags = SA_NOCLDSTOP\|SA_NOCLDWAIT\|SA_RESTART;
	132	assert_se(sigaction(SIGCHLD, &sa, NULL) == 0);
8c43883a	133
6f5e3f35 LP	134	if ((pid = fork()) < 0)
	135	log_error("Failed to fork off crash shell: %s", strerror(errno));
	136	else if (pid == 0) {
	137	execl("/bin/sh", "/bin/sh", NULL);
	138
	139	log_error("execl() failed: %s", strerror(errno));
	140	_exit(1);
	141	}
c99b188e	142
6f5e3f35	143	log_info("Successfully spawned crash shall as pid %llu.", (unsigned long long) pid);
4fc935ca LP	144	}
	145
	146	log_info("Freezing execution.");
97c4f35c LP	147	freeze();
	148	}
	149
	150	static void install_crash_handler(void) {
	151	struct sigaction sa;
	152
	153	zero(sa);
	154
	155	sa.sa_handler = crash;
	156	sa.sa_flags = SA_NODEFER;
	157
	158	assert_se(sigaction(SIGSEGV, &sa, NULL) == 0);
5373d602 LP	159	assert_se(sigaction(SIGILL, &sa, NULL) == 0);
	160	assert_se(sigaction(SIGFPE, &sa, NULL) == 0);
	161	assert_se(sigaction(SIGBUS, &sa, NULL) == 0);
	162	assert_se(sigaction(SIGQUIT, &sa, NULL) == 0);
97c4f35c LP	163	assert_se(sigaction(SIGABRT, &sa, NULL) == 0);
97c4f35c LP	164	}
f170852a	165
80876c20 LP	166	static int console_setup(void) {
	167	int tty_fd = -1, null_fd = -1, r = 0;
	168
	169	/* If we are init, we connect stdout/stderr to /dev/console
	170	* and stdin to /dev/null and make sure we don't have a
	171	* controlling tty. */
	172
	173	release_terminal();
	174
	175	if ((tty_fd = open_terminal("/dev/console", O_WRONLY)) < 0) {
	176	log_error("Failed to open /dev/console: %s", strerror(-tty_fd));
	177	r = -tty_fd;
	178	goto finish;
	179	}
	180
	181	if ((null_fd = open("/dev/null", O_RDONLY)) < 0) {
	182	log_error("Failed to open /dev/null: %m");
	183	r = -errno;
	184	goto finish;
	185	}
	186
	187	assert(tty_fd >= 3);
	188	assert(null_fd >= 3);
	189
	190	if (reset_terminal(tty_fd) < 0)
	191	log_error("Failed to reset /dev/console: %m");
	192
	193	if (dup2(tty_fd, STDOUT_FILENO) < 0 \|\|
	194	dup2(tty_fd, STDERR_FILENO) < 0 \|\|
	195	dup2(null_fd, STDIN_FILENO) < 0) {
	196	log_error("Failed to dup2() device: %m");
	197	r = -errno;
	198	goto finish;
	199	}
	200
	201	r = 0;
	202
	203	finish:
	204	if (tty_fd >= 0)
	205	close_nointr(tty_fd);
	206
	207	if (null_fd >= 0)
	208	close_nointr(null_fd);
	209
	210	return r;
	211	}
	212
f170852a LP	213	static int set_default_unit(const char *u) {
	214	char *c;
	215
	216	assert(u);
	217
	218	if (!(c = strdup(u)))
	219	return -ENOMEM;
	220
	221	free(default_unit);
	222	default_unit = c;
	223	return 0;
	224	}
	225
	226	static int parse_proc_cmdline_word(const char *word) {
	227
	228	static const char * const rlmap[] = {
	229	"single", SPECIAL_RUNLEVEL1_TARGET,
	230	"-s", SPECIAL_RUNLEVEL1_TARGET,
	231	"s", SPECIAL_RUNLEVEL1_TARGET,
	232	"S", SPECIAL_RUNLEVEL1_TARGET,
	233	"1", SPECIAL_RUNLEVEL1_TARGET,
	234	"2", SPECIAL_RUNLEVEL2_TARGET,
	235	"3", SPECIAL_RUNLEVEL3_TARGET,
	236	"4", SPECIAL_RUNLEVEL4_TARGET,
	237	"5", SPECIAL_RUNLEVEL5_TARGET
	238	};
	239
	240	if (startswith(word, "systemd.default="))
82771ba1	241	return set_default_unit(word + 16);
f170852a LP	242
	243	else if (startswith(word, "systemd.log_target=")) {
	244
	245	if (log_set_target_from_string(word + 19) < 0)
	246	log_warning("Failed to parse log target %s. Ignoring.", word + 19);
	247
	248	} else if (startswith(word, "systemd.log_level=")) {
	249
	250	if (log_set_max_level_from_string(word + 18) < 0)
	251	log_warning("Failed to parse log level %s. Ignoring.", word + 18);
	252
4fc935ca LP	253	} else if (startswith(word, "systemd.dump_core=")) {
	254	int r;
	255
	256	if ((r = parse_boolean(word + 18)) < 0)
601f6a1e	257	log_warning("Failed to parse dump core switch %s, Ignoring.", word + 18);
4fc935ca LP	258	else
	259	dump_core = r;
	260
	261	} else if (startswith(word, "systemd.crash_shell=")) {
	262	int r;
	263
	264	if ((r = parse_boolean(word + 20)) < 0)
601f6a1e	265	log_warning("Failed to parse crash shell switch %s, Ignoring.", word + 20);
4fc935ca LP	266	else
	267	crash_shell = r;
	268
5e7ee61c LP	269
	270	} else if (startswith(word, "systemd.confirm_spawn=")) {
	271	int r;
	272
	273	if ((r = parse_boolean(word + 22)) < 0)
	274	log_warning("Failed to parse confirm spawn switch %s, Ignoring.", word + 22);
	275	else
	276	confirm_spawn = r;
	277
601f6a1e LP	278	} else if (startswith(word, "systemd.crash_chvt=")) {
	279	int k;
	280
	281	if (safe_atoi(word + 19, &k) < 0)
	282	log_warning("Failed to parse crash chvt switch %s, Ignoring.", word + 19);
	283	else
	284	crash_chvt = k;
	285
4fc935ca LP	286	} else if (startswith(word, "systemd.")) {
	287
	288	log_warning("Unknown kernel switch %s. Ignoring.", word);
	289
	290	log_info("Supported kernel switches:");
	291	log_info("systemd.default=UNIT Default unit to start");
	292	log_info("systemd.log_target=console\|kmsg\|syslog Log target");
	293	log_info("systemd.log_level=LEVEL Log level");
	294	log_info("systemd.dump_core=0\|1 Dump core on crash");
	295	log_info("systemd.crash_shell=0\|1 On crash run shell");
601f6a1e	296	log_info("systemd.crash_chvt=N Change to VT #N on crash");
5e7ee61c	297	log_info("systemd.confirm_spawn=0\|1 Confirm every process spawn");
4fc935ca	298
f170852a LP	299	} else {
	300	unsigned i;
	301
	302	/* SysV compatibility */
f170852a LP	303	for (i = 0; i < ELEMENTSOF(rlmap); i += 2)
	304	if (streq(word, rlmap[i]))
	305	return set_default_unit(rlmap[i+1]);
	306	}
	307
	308	return 0;
	309	}
	310
	311	static int parse_proc_cmdline(void) {
	312	char *line;
	313	int r;
	314	char *w;
	315	size_t l;
	316	char *state;
	317
	318	if ((r = read_one_line_file("/proc/cmdline", &line)) < 0) {
	319	log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(errno));
	320	return 0;
	321	}
	322
	323	FOREACH_WORD_QUOTED(w, l, line, state) {
	324	char *word;
	325
	326	if (!(word = strndup(w, l))) {
	327	r = -ENOMEM;
	328	goto finish;
	329	}
	330
	331	r = parse_proc_cmdline_word(word);
	332	free(word);
	333
	334	if (r < 0)
	335	goto finish;
	336	}
	337
	338	r = 0;
	339
	340	finish:
	341	free(line);
	342	return r;
	343	}
	344
	345	static int parse_argv(int argc, char *argv[]) {
	346
	347	enum {
	348	ARG_LOG_LEVEL = 0x100,
	349	ARG_LOG_TARGET,
a5dab5ce	350	ARG_DEFAULT,
e965d56d	351	ARG_RUNNING_AS,
e537352b	352	ARG_TEST,
80876c20 LP	353	ARG_DUMP_CONFIGURATION_ITEMS,
80876c20 LP	354	ARG_CONFIRM_SPAWN
f170852a LP	355	};
	356
	357	static const struct option options[] = {
	358	{ "log-level", required_argument, NULL, ARG_LOG_LEVEL },
	359	{ "log-target", required_argument, NULL, ARG_LOG_TARGET },
	360	{ "default", required_argument, NULL, ARG_DEFAULT },
a5dab5ce	361	{ "running-as", required_argument, NULL, ARG_RUNNING_AS },
e965d56d	362	{ "test", no_argument, NULL, ARG_TEST },
f170852a	363	{ "help", no_argument, NULL, 'h' },
e537352b	364	{ "dump-configuration-items", no_argument, NULL, ARG_DUMP_CONFIGURATION_ITEMS },
80876c20	365	{ "confirm-spawn", no_argument, NULL, ARG_CONFIRM_SPAWN },
f170852a LP	366	{ NULL, 0, NULL, 0 }
	367	};
	368
	369	int c, r;
	370
	371	assert(argc >= 1);
	372	assert(argv);
	373
	374	while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
	375
	376	switch (c) {
	377
	378	case ARG_LOG_LEVEL:
	379	if ((r = log_set_max_level_from_string(optarg)) < 0) {
	380	log_error("Failed to parse log level %s.", optarg);
	381	return r;
	382	}
	383
	384	break;
	385
	386	case ARG_LOG_TARGET:
	387
	388	if ((r = log_set_target_from_string(optarg)) < 0) {
	389	log_error("Failed to parse log target %s.", optarg);
	390	return r;
	391	}
	392
	393	break;
	394
	395	case ARG_DEFAULT:
	396
	397	if ((r = set_default_unit(optarg)) < 0) {
	398	log_error("Failed to set default unit %s: %s", optarg, strerror(-r));
	399	return r;
	400	}
	401
	402	break;
	403
a5dab5ce LP	404	case ARG_RUNNING_AS: {
	405	ManagerRunningAs as;
	406
	407	if ((as = manager_running_as_from_string(optarg)) < 0) {
	408	log_error("Failed to parse running as value %s", optarg);
	409	return -EINVAL;
	410	}
	411
	412	running_as = as;
	413	break;
	414	}
	415
e965d56d LP	416	case ARG_TEST:
	417	action = ACTION_TEST;
	418	break;
	419
e537352b LP	420	case ARG_DUMP_CONFIGURATION_ITEMS:
	421	action = ACTION_DUMP_CONFIGURATION_ITEMS;
	422	break;
	423
80876c20 LP	424	case ARG_CONFIRM_SPAWN:
	425	confirm_spawn = true;
	426	break;
	427
f170852a LP	428	case 'h':
	429	action = ACTION_HELP;
	430	break;
	431
	432	case '?':
	433	return -EINVAL;
	434
	435	default:
	436	log_error("Unknown option code %c", c);
	437	return -EINVAL;
	438	}
	439
f170852a LP	440	return 0;
	441	}
	442
	443	static int help(void) {
	444
	445	printf("%s [options]\n\n"
e537352b LP	446	" -h --help Show this help\n"
	447	" --default=UNIT Set default unit\n"
	448	" --log-level=LEVEL Set log level\n"
	449	" --log-target=TARGET Set log target (console, syslog, kmsg)\n"
	450	" --running-as=AS Set running as (init, system, session)\n"
	451	" --test Determine startup sequence, dump it and exit\n"
80876c20 LP	452	" --dump-configuration-items Dump understood unit configuration items\n"
80876c20 LP	453	" --confirm-spawn Ask for confirmation when spawning processes\n",
f170852a LP	454	__progname);
	455
	456	return 0;
	457	}
	458
60918275 LP	459	int main(int argc, char *argv[]) {
60918275 LP	460	Manager *m = NULL;
87f0e418	461	Unit *target = NULL;
60918275 LP	462	Job *job = NULL;
60918275 LP	463	int r, retval = 1;
27b14a22	464
a5dab5ce LP	465	if (getpid() == 1)
	466	running_as = MANAGER_INIT;
	467	else if (getuid() == 0)
	468	running_as = MANAGER_SYSTEM;
	469	else
	470	running_as = MANAGER_SESSION;
	471
f170852a LP	472	if (set_default_unit(SPECIAL_DEFAULT_TARGET) < 0)
f170852a LP	473	goto finish;
60918275	474
f170852a LP	475	/* Mount /proc, /sys and friends, so that /proc/cmdline and
f170852a LP	476	* /proc/$PID/fd is available. */
d89e521e LP	477	if (mount_setup() < 0)
d89e521e LP	478	goto finish;
4ade7963 LP	479
	480	/* Reset all signal handlers. */
	481	assert_se(reset_all_signal_handlers() == 0);
	482
078e4539	483	/* If we are init, we can block sigkill. Yay. */
a337c6fc LP	484	ignore_signal(SIGKILL);
a337c6fc LP	485	ignore_signal(SIGPIPE);
078e4539	486
f170852a LP	487	/* Close all open files */
	488	assert_se(close_all_fds(NULL, 0) == 0);
	489
a5dab5ce LP	490	if (running_as != MANAGER_SESSION)
	491	if (parse_proc_cmdline() < 0)
	492	goto finish;
f170852a LP	493
	494	log_parse_environment();
	495
	496	if (parse_argv(argc, argv) < 0)
	497	goto finish;
	498
	499	if (action == ACTION_HELP) {
	500	retval = help();
	501	goto finish;
e537352b LP	502	} else if (action == ACTION_DUMP_CONFIGURATION_ITEMS) {
	503	unit_dump_config_items(stdout);
	504	retval = 0;
	505	goto finish;
f170852a LP	506	}
f170852a LP	507
e965d56d	508	assert_se(action == ACTION_RUN \|\| action == ACTION_TEST);
f170852a	509
09082a94	510	/* Set up PATH unless it is already set */
e537352b LP	511	setenv("PATH",
	512	"/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
	513	running_as == MANAGER_INIT);
09082a94	514
f170852a LP	515	/* Move out of the way, so that we won't block unmounts */
	516	assert_se(chdir("/") == 0);
	517
80876c20 LP	518	if (running_as != MANAGER_SESSION) {
	519	/* Become a session leader if we aren't one yet. */
	520	setsid();
4ade7963	521
80876c20 LP	522	/* Disable the umask logic */
	523	umask(0);
	524	}
	525
	526	if (running_as == MANAGER_INIT)
	527	console_setup();
4ade7963 LP	528
	529	/* Make sure D-Bus doesn't fiddle with the SIGPIPE handlers */
	530	dbus_connection_set_change_sigpipe(FALSE);
	531
18149b9f	532	/* Open the logging devices, if possible and necessary */
4ade7963 LP	533	log_open_syslog();
	534	log_open_kmsg();
	535
5373d602 LP	536	/* Make sure we leave a core dump without panicing the
5373d602 LP	537	* kernel. */
4fc935ca LP	538	if (getpid() == 1)
4fc935ca LP	539	install_crash_handler();
97c4f35c	540
a5dab5ce LP	541	log_debug("systemd running in %s mode.", manager_running_as_to_string(running_as));
a5dab5ce LP	542
302e8c4c	543	if (running_as == MANAGER_INIT)
e537352b	544	hostname_setup();
302e8c4c	545
80876c20	546	if ((r = manager_new(running_as, confirm_spawn, &m)) < 0) {
8e274523	547	log_error("Failed to allocate manager object: %s", strerror(-r));
60918275 LP	548	goto finish;
	549	}
	550
f50e0a01 LP	551	if ((r = manager_coldplug(m)) < 0) {
	552	log_error("Failed to retrieve coldplug information: %s", strerror(-r));
	553	goto finish;
	554	}
	555
27b14a22 LP	556	log_debug("Activating default unit: %s", default_unit);
27b14a22 LP	557
9e2f7c11	558	if ((r = manager_load_unit(m, default_unit, NULL, &target)) < 0) {
c22cbe26	559	log_error("Failed to load default target: %s", strerror(-r));
37d88da7 LP	560
37d88da7 LP	561	log_info("Trying to load rescue target...");
9e2f7c11	562	if ((r = manager_load_unit(m, SPECIAL_RESCUE_TARGET, NULL, &target)) < 0) {
37d88da7 LP	563	log_error("Failed to load rescue target: %s", strerror(-r));
	564	goto finish;
	565	}
60918275 LP	566	}
60918275 LP	567
e965d56d LP	568	if (action == ACTION_TEST) {
	569	printf("→ By units:\n");
	570	manager_dump_units(m, stdout, "\t");
	571	}
d46de8a1	572
8f5847c4 LP	573	if ((r = manager_add_job(m, JOB_START, target, JOB_REPLACE, false, &job)) < 0) {
	574	log_error("Failed to start default target: %s", strerror(-r));
	575	goto finish;
	576	}
11dd41ce	577
e965d56d LP	578	if (action == ACTION_TEST) {
	579	printf("→ By jobs:\n");
	580	manager_dump_jobs(m, stdout, "\t");
	581
	582	if (getpid() == 1)
	583	pause();
	584
	585	retval = 0;
	586	goto finish;
	587	}
cea8e32e	588
c20cae32 LP	589	if ((r = manager_loop(m)) < 0) {
	590	log_error("Failed to run mainloop: %s", strerror(-r));
	591	goto finish;
	592	}
9152c765	593
60918275 LP	594	retval = 0;
60918275 LP	595
f170852a LP	596	log_debug("Exit.");
f170852a LP	597
60918275 LP	598	finish:
	599	if (m)
	600	manager_free(m);
	601
f170852a	602	free(default_unit);
b9cd2ec1	603
ea430986 LP	604	dbus_shutdown();
ea430986 LP	605
c3b3c274 LP	606	if (getpid() == 1)
	607	freeze();
	608
60918275 LP	609	return retval;
60918275 LP	610	}