1 /* vi: set sw=4 ts=4: */
3 * Mini init implementation for busybox
5 * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
6 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
7 * Adjusted by so many folks, it's impossible to keep track.
9 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
15 #include <sys/ioctl.h>
17 #include <sys/reboot.h>
19 #if ENABLE_FEATURE_INIT_SYSLOG
20 # include <sys/syslog.h>
23 #define INIT_BUFFS_SIZE 256
24 #define CONSOLE_NAME_SIZE 32
25 #define MAXENV 16 /* Number of env. vars */
28 #define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
31 #if ENABLE_FEATURE_INIT_COREDUMPS
33 * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
34 * before processes are spawned to set core file size as unlimited.
35 * This is for debugging only. Don't use this is production, unless
36 * you want core dumps lying about....
38 #define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
39 #include <sys/resource.h>
42 #define INITTAB "/etc/inittab" /* inittab file location */
44 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
47 /* Allowed init action types */
50 #define ASKFIRST 0x004
53 #define CTRLALTDEL 0x020
54 #define SHUTDOWN 0x040
57 /* A mapping between "inittab" action name strings and action type codes. */
58 struct init_action_type {
63 static const struct init_action_type actions[] = {
66 {"askfirst", ASKFIRST},
69 {"ctrlaltdel", CTRLALTDEL},
70 {"shutdown", SHUTDOWN},
75 /* Set up a linked list of init_actions, to be read from inittab */
77 struct init_action *next;
80 char command[INIT_BUFFS_SIZE];
81 char terminal[CONSOLE_NAME_SIZE];
84 /* Static variables */
85 static struct init_action *init_action_list = NULL;
87 #if !ENABLE_FEATURE_INIT_SYSLOG
88 static const char *log_console = VC_5;
90 #if !ENABLE_DEBUG_INIT
91 static sig_atomic_t got_cont = 0;
98 #if ENABLE_FEATURE_EXTRA_QUIET
101 MAYBE_CONSOLE = L_CONSOLE,
104 #ifndef RB_HALT_SYSTEM
105 RB_HALT_SYSTEM = 0xcdef0123, /* FIXME: this overflows enum */
106 RB_ENABLE_CAD = 0x89abcdef,
108 RB_POWER_OFF = 0x4321fedc,
109 RB_AUTOBOOT = 0x01234567,
113 static const char * const environment[] = {
115 "PATH=" _PATH_STDPATH,
121 /* Function prototypes */
122 static void delete_init_action(struct init_action *a);
123 static int waitfor(const struct init_action *a, pid_t pid);
124 #if !ENABLE_DEBUG_INIT
125 static void shutdown_signal(int sig);
128 #if !ENABLE_DEBUG_INIT
129 static void loop_forever(void)
136 /* Print a message to the specified device.
137 * Device may be bitwise-or'd from L_LOG | L_CONSOLE */
138 #if ENABLE_DEBUG_INIT
139 #define messageD message
141 #define messageD(...) do {} while (0)
143 static void message(int device, const char *fmt, ...)
144 __attribute__ ((format(printf, 2, 3)));
145 static void message(int device, const char *fmt, ...)
147 #if !ENABLE_FEATURE_INIT_SYSLOG
148 static int log_fd = -1;
156 va_start(arguments, fmt);
157 vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments);
159 msg[sizeof(msg) - 2] = '\0';
162 #if ENABLE_FEATURE_INIT_SYSLOG
163 /* Log the message to syslogd */
164 if (device & L_LOG) {
166 openlog(applet_name, 0, LOG_DAEMON);
167 syslog(LOG_INFO, "init: %s", msg + 1);
175 /* Take full control of the log tty, and never close it.
176 * It's mine, all mine! Muhahahaha! */
181 log_fd = device_open(log_console, O_WRONLY | O_NONBLOCK | O_NOCTTY);
183 bb_error_msg("can't log to %s", log_console);
186 fcntl(log_fd, F_SETFD, FD_CLOEXEC);
190 if (device & L_LOG) {
191 full_write(log_fd, msg, l);
193 return; /* don't print dup messages */
197 if (device & L_CONSOLE) {
198 /* Send console messages to console so people will see them. */
199 full_write(2, msg, l);
203 /* Set terminal settings to reasonable defaults */
204 static void set_sane_term(void)
208 tcgetattr(STDIN_FILENO, &tty);
210 /* set control chars */
211 tty.c_cc[VINTR] = 3; /* C-c */
212 tty.c_cc[VQUIT] = 28; /* C-\ */
213 tty.c_cc[VERASE] = 127; /* C-? */
214 tty.c_cc[VKILL] = 21; /* C-u */
215 tty.c_cc[VEOF] = 4; /* C-d */
216 tty.c_cc[VSTART] = 17; /* C-q */
217 tty.c_cc[VSTOP] = 19; /* C-s */
218 tty.c_cc[VSUSP] = 26; /* C-z */
220 /* use line dicipline 0 */
223 /* Make it be sane */
224 tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
225 tty.c_cflag |= CREAD | HUPCL | CLOCAL;
228 tty.c_iflag = ICRNL | IXON | IXOFF;
231 tty.c_oflag = OPOST | ONLCR;
235 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
237 tcsetattr(STDIN_FILENO, TCSANOW, &tty);
240 /* From <linux/serial.h> */
241 struct serial_struct {
250 unsigned short close_delay;
252 char reserved_char[1];
254 unsigned short closing_wait; /* time to wait before closing */
255 unsigned short closing_wait2; /* no longer used... */
256 unsigned char *iomem_base;
257 unsigned short iomem_reg_shift;
258 unsigned int port_high;
259 unsigned long iomap_base; /* cookie passed into ioremap */
261 /* Paranoia (imagine 64bit kernel overwriting 32bit userspace stack) */
262 uint32_t bbox_reserved[16];
264 static void console_init(void)
266 struct serial_struct sr;
269 s = getenv("CONSOLE");
270 if (!s) s = getenv("console");
272 int fd = open(s, O_RDWR | O_NONBLOCK | O_NOCTTY);
277 while (fd > 2) close(fd--);
279 messageD(L_LOG, "console='%s'", s);
283 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
284 /* Force the TERM setting to vt102 for serial console --
285 * if TERM is set to linux (the default) */
286 if (!s || strcmp(s, "linux") == 0)
287 putenv((char*)"TERM=vt102");
288 #if !ENABLE_FEATURE_INIT_SYSLOG
292 putenv((char*)"TERM=linux");
295 static void fixup_argv(int argc, char **argv, const char *new_argv0)
299 /* Fix up argv[0] to be certain we claim to be init */
300 len = strlen(argv[0]);
301 strncpy(argv[0], new_argv0, len);
303 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
306 memset(argv[len], 0, strlen(argv[len]));
311 /* Open the new terminal device */
312 static void open_stdio_to_tty(const char* tty_name, int fail)
314 /* empty tty_name means "use init's tty", else... */
316 int fd = device_open(tty_name, O_RDWR);
318 message(L_LOG | L_CONSOLE, "Can't open %s: %s",
319 tty_name, strerror(errno));
322 #if !ENABLE_DEBUG_INIT
323 shutdown_signal(SIGUSR1);
331 if (fd > 2) close(fd);
337 static pid_t run(const struct init_action *a)
341 char *s, *tmpCmd, *cmdpath;
342 char *cmd[INIT_BUFFS_SIZE];
343 char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
344 sigset_t nmask, omask;
346 /* Block sigchild while forking. */
348 sigaddset(&nmask, SIGCHLD);
349 sigprocmask(SIG_BLOCK, &nmask, &omask);
351 sigprocmask(SIG_SETMASK, &omask, NULL);
356 /* Reset signal handlers that were set by the parent process */
357 signal(SIGUSR1, SIG_DFL);
358 signal(SIGUSR2, SIG_DFL);
359 signal(SIGINT, SIG_DFL);
360 signal(SIGTERM, SIG_DFL);
361 signal(SIGHUP, SIG_DFL);
362 signal(SIGQUIT, SIG_DFL);
363 signal(SIGCONT, SIG_DFL);
364 signal(SIGSTOP, SIG_DFL);
365 signal(SIGTSTP, SIG_DFL);
367 /* Create a new session and make ourself the process
371 /* Open the new terminal device */
372 open_stdio_to_tty(a->terminal, 1);
374 /* If the init Action requires us to wait, then force the
375 * supplied terminal to be the controlling tty. */
376 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
378 /* Now fork off another process to just hang around */
379 if ((pid = fork()) < 0) {
380 message(L_LOG | L_CONSOLE, "Can't fork");
386 /* We are the parent -- wait till the child is done */
387 signal(SIGINT, SIG_IGN);
388 signal(SIGTSTP, SIG_IGN);
389 signal(SIGQUIT, SIG_IGN);
390 signal(SIGCHLD, SIG_DFL);
393 /* See if stealing the controlling tty back is necessary */
394 if (tcgetpgrp(0) != getpid())
397 /* Use a temporary process to steal the controlling tty. */
398 if ((pid = fork()) < 0) {
399 message(L_LOG | L_CONSOLE, "Can't fork");
404 ioctl(0, TIOCSCTTY, 1);
411 /* Now fall though to actually execute things */
414 /* See if any special /bin/sh requiring characters are present */
415 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
416 cmd[0] = (char*)DEFAULT_SHELL;
417 cmd[1] = (char*)"-c";
418 cmd[2] = strcat(strcpy(buf, "exec "), a->command);
421 /* Convert command (char*) into cmd (char**, one word per string) */
422 strcpy(buf, a->command);
424 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
425 if (*tmpCmd != '\0') {
436 * Interactive shells want to see a dash in argv[0]. This
437 * typically is handled by login, argv will be setup this
438 * way if a dash appears at the front of the command path
441 if (*cmdpath == '-') {
442 /* skip over the dash */
445 /* find the last component in the command pathname */
446 s = bb_get_last_path_component(cmdpath);
448 /* make a new argv[0] */
449 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
450 message(L_LOG | L_CONSOLE, bb_msg_memory_exhausted);
454 strcpy(cmd[0] + 1, s);
456 #if ENABLE_FEATURE_INIT_SCTTY
457 /* Establish this process as session leader and
458 * (attempt) to make the tty (if any) a controlling tty.
461 ioctl(0, TIOCSCTTY, 0 /*don't steal it*/);
465 #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
466 if (a->action & ASKFIRST) {
467 static const char press_enter[] =
468 #ifdef CUSTOMIZED_BANNER
469 #include CUSTOMIZED_BANNER
471 "\nPlease press Enter to activate this console. ";
474 * Save memory by not exec-ing anything large (like a shell)
475 * before the user wants it. This is critical if swap is not
476 * enabled and the system has low memory. Generally this will
477 * be run on the second virtual console, and the first will
478 * be allowed to start a shell or whatever an init script
481 messageD(L_LOG, "waiting for enter to start '%s'"
482 "(pid %d, tty '%s')\n",
483 cmdpath, getpid(), a->terminal);
484 full_write(1, press_enter, sizeof(press_enter) - 1);
485 while (read(0, &c, 1) == 1 && c != '\n')
489 /* Log the process name and args */
490 message(L_LOG, "starting pid %d, tty '%s': '%s'",
491 getpid(), a->terminal, cmdpath);
493 #if ENABLE_FEATURE_INIT_COREDUMPS
496 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
499 limit.rlim_cur = RLIM_INFINITY;
500 limit.rlim_max = RLIM_INFINITY;
501 setrlimit(RLIMIT_CORE, &limit);
505 /* Now run it. The new program will take over this PID,
506 * so nothing further in init.c should be run. */
507 BB_EXECVP(cmdpath, cmd);
509 /* We're still here? Some error happened. */
510 message(L_LOG | L_CONSOLE, "Cannot run '%s': %s",
511 cmdpath, strerror(errno));
515 static int waitfor(const struct init_action *a, pid_t pid)
520 runpid = (NULL == a)? pid : run(a);
522 wpid = waitpid(runpid, &status, 0);
525 if (wpid == -1 && errno == ECHILD) {
526 /* we missed its termination */
529 /* FIXME other errors should maybe trigger an error, but allow
530 * the program to continue */
535 /* Run all commands of a particular type */
536 static void run_actions(int action)
538 struct init_action *a, *tmp;
540 for (a = init_action_list; a; a = tmp) {
542 if (a->action == action) {
543 /* a->terminal of "" means "init's console" */
544 if (a->terminal[0] && access(a->terminal, R_OK | W_OK)) {
545 delete_init_action(a);
546 } else if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
548 delete_init_action(a);
549 } else if (a->action & ONCE) {
551 delete_init_action(a);
552 } else if (a->action & (RESPAWN | ASKFIRST)) {
553 /* Only run stuff with pid==0. If they have
554 * a pid, that means it is still running */
563 #if !ENABLE_DEBUG_INIT
564 static void init_reboot(unsigned long magic)
567 /* We have to fork here, since the kernel calls do_exit(0) in
568 * linux/kernel/sys.c, which can cause the machine to panic when
569 * the init process is killed.... */
571 if (pid == 0) { /* child */
575 waitpid(pid, NULL, 0);
578 static void shutdown_system(void)
580 sigset_t block_signals;
582 /* run everything to be run at "shutdown". This is done _prior_
583 * to killing everything, in case people wish to use scripts to
584 * shut things down gracefully... */
585 run_actions(SHUTDOWN);
587 /* first disable all our signals */
588 sigemptyset(&block_signals);
589 sigaddset(&block_signals, SIGHUP);
590 sigaddset(&block_signals, SIGQUIT);
591 sigaddset(&block_signals, SIGCHLD);
592 sigaddset(&block_signals, SIGUSR1);
593 sigaddset(&block_signals, SIGUSR2);
594 sigaddset(&block_signals, SIGINT);
595 sigaddset(&block_signals, SIGTERM);
596 sigaddset(&block_signals, SIGCONT);
597 sigaddset(&block_signals, SIGSTOP);
598 sigaddset(&block_signals, SIGTSTP);
599 sigprocmask(SIG_BLOCK, &block_signals, NULL);
601 message(L_CONSOLE | L_LOG, "The system is going down NOW!");
603 /* Allow Ctrl-Alt-Del to reboot system. */
604 init_reboot(RB_ENABLE_CAD);
606 /* Send signals to every process _except_ pid 1 */
607 message(L_CONSOLE | L_LOG, "Sending SIG%s to all processes", "TERM");
612 message(L_CONSOLE | L_LOG, "Sending SIG%s to all processes", "KILL");
618 static void exec_signal(int sig ATTRIBUTE_UNUSED)
620 struct init_action *a, *tmp;
621 sigset_t unblock_signals;
623 for (a = init_action_list; a; a = tmp) {
625 if (a->action & RESTART) {
628 /* unblock all signals, blocked in shutdown_system() */
629 sigemptyset(&unblock_signals);
630 sigaddset(&unblock_signals, SIGHUP);
631 sigaddset(&unblock_signals, SIGQUIT);
632 sigaddset(&unblock_signals, SIGCHLD);
633 sigaddset(&unblock_signals, SIGUSR1);
634 sigaddset(&unblock_signals, SIGUSR2);
635 sigaddset(&unblock_signals, SIGINT);
636 sigaddset(&unblock_signals, SIGTERM);
637 sigaddset(&unblock_signals, SIGCONT);
638 sigaddset(&unblock_signals, SIGSTOP);
639 sigaddset(&unblock_signals, SIGTSTP);
640 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
642 /* Open the new terminal device */
643 open_stdio_to_tty(a->terminal, 0);
645 messageD(L_CONSOLE | L_LOG, "Trying to re-exec %s", a->command);
646 BB_EXECLP(a->command, a->command, NULL);
648 message(L_CONSOLE | L_LOG, "Cannot run '%s': %s",
649 a->command, strerror(errno));
651 init_reboot(RB_HALT_SYSTEM);
657 static void shutdown_signal(int sig)
666 if (sig == SIGTERM) {
669 } else if (sig == SIGUSR2) {
673 message(L_CONSOLE | L_LOG, "Requesting system %s", m);
674 /* allow time for last message to reach serial console */
680 static void ctrlaltdel_signal(int sig ATTRIBUTE_UNUSED)
682 run_actions(CTRLALTDEL);
685 /* The SIGSTOP & SIGTSTP handler */
686 static void stop_handler(int sig ATTRIBUTE_UNUSED)
688 int saved_errno = errno;
697 /* The SIGCONT handler */
698 static void cont_handler(int sig ATTRIBUTE_UNUSED)
703 #endif /* !ENABLE_DEBUG_INIT */
705 static void new_init_action(int action, const char *command, const char *cons)
707 struct init_action *new_action, *a, *last;
709 if (strcmp(cons, bb_dev_null) == 0 && (action & ASKFIRST))
712 /* Append to the end of the list */
713 for (a = last = init_action_list; a; a = a->next) {
714 /* don't enter action if it's already in the list,
715 * but do overwrite existing actions */
716 if ((strcmp(a->command, command) == 0)
717 && (strcmp(a->terminal, cons) == 0)
725 new_action = xzalloc(sizeof(struct init_action));
727 last->next = new_action;
729 init_action_list = new_action;
731 strcpy(new_action->command, command);
732 new_action->action = action;
733 strcpy(new_action->terminal, cons);
734 messageD(L_LOG | L_CONSOLE, "command='%s' action=%d tty='%s'\n",
735 new_action->command, new_action->action, new_action->terminal);
738 static void delete_init_action(struct init_action *action)
740 struct init_action *a, *b = NULL;
742 for (a = init_action_list; a; b = a, a = a->next) {
745 init_action_list = a->next;
755 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
756 * then parse_inittab() simply adds in some default
757 * actions(i.e., runs INIT_SCRIPT and then starts a pair
758 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
759 * _is_ defined, but /etc/inittab is missing, this
760 * results in the same set of default behaviors.
762 static void parse_inittab(void)
764 #if ENABLE_FEATURE_USE_INITTAB
766 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
767 char tmpConsole[CONSOLE_NAME_SIZE];
768 char *id, *runlev, *action, *command, *eol;
769 const struct init_action_type *a = actions;
771 file = fopen(INITTAB, "r");
773 /* No inittab file -- set up some default behavior */
775 /* Reboot on Ctrl-Alt-Del */
776 new_init_action(CTRLALTDEL, "reboot", "");
777 /* Umount all filesystems on halt/reboot */
778 new_init_action(SHUTDOWN, "umount -a -r", "");
779 /* Swapoff on halt/reboot */
780 if (ENABLE_SWAPONOFF) new_init_action(SHUTDOWN, "swapoff -a", "");
781 /* Prepare to restart init when a HUP is received */
782 new_init_action(RESTART, "init", "");
783 /* Askfirst shell on tty1-4 */
784 new_init_action(ASKFIRST, bb_default_login_shell, "");
785 new_init_action(ASKFIRST, bb_default_login_shell, VC_2);
786 new_init_action(ASKFIRST, bb_default_login_shell, VC_3);
787 new_init_action(ASKFIRST, bb_default_login_shell, VC_4);
789 new_init_action(SYSINIT, INIT_SCRIPT, "");
792 #if ENABLE_FEATURE_USE_INITTAB
795 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
796 /* Skip leading spaces */
797 for (id = buf; *id == ' ' || *id == '\t'; id++);
799 /* Skip the line if it's a comment */
800 if (*id == '#' || *id == '\n')
803 /* Trim the trailing \n */
805 eol = strrchr(id, '\n');
809 /* Keep a copy around for posterity's sake (and error msgs) */
810 strcpy(lineAsRead, buf);
812 /* Separate the ID field from the runlevels */
813 runlev = strchr(id, ':');
814 if (runlev == NULL || *(runlev + 1) == '\0') {
815 message(L_LOG | L_CONSOLE, "Bad inittab entry: %s", lineAsRead);
822 /* Separate the runlevels from the action */
823 action = strchr(runlev, ':');
824 if (action == NULL || *(action + 1) == '\0') {
825 message(L_LOG | L_CONSOLE, "Bad inittab entry: %s", lineAsRead);
832 /* Separate the action from the command */
833 command = strchr(action, ':');
834 if (command == NULL || *(command + 1) == '\0') {
835 message(L_LOG | L_CONSOLE, "Bad inittab entry: %s", lineAsRead);
842 /* Ok, now process it */
843 for (a = actions; a->name != 0; a++) {
844 if (strcmp(a->name, action) == 0) {
846 if(strncmp(id, "/dev/", 5) == 0)
848 strcpy(tmpConsole, "/dev/");
849 safe_strncpy(tmpConsole + 5, id,
850 sizeof(tmpConsole) - 5);
853 new_init_action(a->action, command, id);
858 /* Choke on an unknown action */
859 message(L_LOG | L_CONSOLE, "Bad inittab entry: %s", lineAsRead);
863 #endif /* FEATURE_USE_INITTAB */
866 #if ENABLE_FEATURE_USE_INITTAB
867 static void reload_signal(int sig ATTRIBUTE_UNUSED)
869 struct init_action *a, *tmp;
871 message(L_LOG, "reloading /etc/inittab");
873 /* disable old entrys */
874 for (a = init_action_list; a; a = a->next ) {
880 /* remove unused entrys */
881 for (a = init_action_list; a; a = tmp) {
883 if ((a->action & (ONCE | SYSINIT | WAIT)) && a->pid == 0) {
884 delete_init_action(a);
887 run_actions(RESPAWN);
889 #endif /* FEATURE_USE_INITTAB */
891 int init_main(int argc, char **argv);
892 int init_main(int argc, char **argv)
894 struct init_action *a;
897 die_sleep = 30 * 24*60*60; /* if xmalloc will ever die... */
899 if (argc > 1 && !strcmp(argv[1], "-q")) {
900 return kill(1, SIGHUP);
902 #if !ENABLE_DEBUG_INIT
903 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
905 && (!ENABLE_FEATURE_INITRD || !strstr(applet_name, "linuxrc"))
909 /* Set up sig handlers -- be sure to
910 * clear all of these in run() */
911 signal(SIGHUP, exec_signal);
912 signal(SIGQUIT, exec_signal);
913 signal(SIGUSR1, shutdown_signal);
914 signal(SIGUSR2, shutdown_signal);
915 signal(SIGINT, ctrlaltdel_signal);
916 signal(SIGTERM, shutdown_signal);
917 signal(SIGCONT, cont_handler);
918 signal(SIGSTOP, stop_handler);
919 signal(SIGTSTP, stop_handler);
921 /* Turn off rebooting via CTL-ALT-DEL -- we get a
922 * SIGINT on CAD so we can shut things down gracefully... */
923 init_reboot(RB_DISABLE_CAD);
926 /* Figure out where the default console should be */
932 const char * const *e;
933 /* Make sure environs is set to something sane */
934 for (e = environment; *e; e++)
938 if (argc > 1) setenv("RUNLEVEL", argv[1], 1);
941 message(MAYBE_CONSOLE | L_LOG, "init started: %s", bb_msg_full_version);
943 /* Make sure there is enough memory to do something useful. */
944 if (ENABLE_SWAPONOFF) {
947 if (!sysinfo(&info) &&
948 (info.mem_unit ? : 1) * (long long)info.totalram < 1024*1024)
950 message(L_CONSOLE, "Low memory, forcing swapon");
951 /* swapon -a requires /proc typically */
952 new_init_action(SYSINIT, "mount -t proc proc /proc", "");
953 /* Try to turn on swap */
954 new_init_action(SYSINIT, "swapon -a", "");
955 run_actions(SYSINIT); /* wait and removing */
959 /* Check if we are supposed to be in single user mode */
961 && (!strcmp(argv[1], "single") || !strcmp(argv[1], "-s") || LONE_CHAR(argv[1], '1'))
963 /* Start a shell on console */
964 new_init_action(RESPAWN, bb_default_login_shell, "");
966 /* Not in single user mode -- see what inittab says */
968 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
969 * then parse_inittab() simply adds in some default
970 * actions(i.e., runs INIT_SCRIPT and then starts a pair
971 * of "askfirst" shells */
976 if (getenv("SELINUX_INIT") == NULL) {
979 putenv("SELINUX_INIT=YES");
980 if (selinux_init_load_policy(&enforce) == 0) {
981 BB_EXECVP(argv[0], argv);
982 } else if (enforce > 0) {
983 /* SELinux in enforcing mode but load_policy failed */
984 /* At this point, we probably can't open /dev/console, so log() won't work */
985 message(L_CONSOLE, "Cannot load SELinux Policy. "
986 "Machine is in enforcing mode. Halting now.");
990 #endif /* CONFIG_SELINUX */
992 /* Make the command line just say "init" -- thats all, nothing else */
993 fixup_argv(argc, argv, "init");
995 /* Now run everything that needs to be run */
997 /* First run the sysinit command */
998 run_actions(SYSINIT);
1000 /* Next run anything that wants to block */
1003 /* Next run anything to be run only once */
1006 #if ENABLE_FEATURE_USE_INITTAB
1007 /* Redefine SIGHUP to reread /etc/inittab */
1008 signal(SIGHUP, reload_signal);
1010 signal(SIGHUP, SIG_IGN);
1011 #endif /* FEATURE_USE_INITTAB */
1013 /* Now run the looping stuff for the rest of forever */
1015 /* run the respawn stuff */
1016 run_actions(RESPAWN);
1018 /* run the askfirst stuff */
1019 run_actions(ASKFIRST);
1021 /* Don't consume all CPU time -- sleep a bit */
1024 /* Wait for a child process to exit */
1027 /* Find out who died and clean up their corpse */
1028 for (a = init_action_list; a; a = a->next) {
1029 if (a->pid == wpid) {
1030 /* Set the pid to 0 so that the process gets
1031 * restarted by run_actions() */
1033 message(L_LOG, "process '%s' (pid %d) exited. "
1034 "Scheduling it for restart.",
1038 /* see if anyone else is waiting to be reaped */
1039 wpid = waitpid(-1, NULL, WNOHANG);