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 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 /* Turn this on to disable all the dangerous
26 rebooting stuff when debugging.
40 #include <sys/fcntl.h>
41 #include <sys/ioctl.h>
42 #include <sys/mount.h>
43 #include <sys/types.h>
45 #include <sys/reboot.h>
48 #include "init_shared.h"
52 # include <sys/syslog.h>
56 #define INIT_BUFFS_SIZE 256
58 /* From <linux/vt.h> */
60 unsigned short v_active; /* active vt */
61 unsigned short v_signal; /* signal to send */
62 unsigned short v_state; /* vt bitmask */
64 static const int VT_GETSTATE = 0x5603; /* get global vt state info */
66 /* From <linux/serial.h> */
67 struct serial_struct {
76 unsigned short close_delay;
78 char reserved_char[1];
80 unsigned short closing_wait; /* time to wait before closing */
81 unsigned short closing_wait2; /* no longer used... */
82 unsigned char *iomem_base;
83 unsigned short iomem_reg_shift;
84 unsigned int port_high;
85 unsigned long iomap_base; /* cookie passed into ioremap */
91 #define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
94 #if defined CONFIG_FEATURE_INIT_COREDUMPS
96 * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
97 * before processes are spawned to set core file size as unlimited.
98 * This is for debugging only. Don't use this is production, unless
99 * you want core dumps lying about....
101 #define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
102 #include <sys/resource.h>
103 #include <sys/time.h>
106 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
108 #define INITTAB "/etc/inittab" /* inittab file location */
110 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
113 #define MAXENV 16 /* Number of env. vars */
115 #define CONSOLE_BUFF_SIZE 32
117 /* Allowed init action types */
118 #define SYSINIT 0x001
119 #define RESPAWN 0x002
120 #define ASKFIRST 0x004
123 #define CTRLALTDEL 0x020
124 #define SHUTDOWN 0x040
125 #define RESTART 0x080
127 /* A mapping between "inittab" action name strings and action type codes. */
128 struct init_action_type {
133 static const struct init_action_type actions[] = {
134 {"sysinit", SYSINIT},
135 {"respawn", RESPAWN},
136 {"askfirst", ASKFIRST},
139 {"ctrlaltdel", CTRLALTDEL},
140 {"shutdown", SHUTDOWN},
141 {"restart", RESTART},
145 /* Set up a linked list of init_actions, to be read from inittab */
148 char command[INIT_BUFFS_SIZE];
149 char terminal[CONSOLE_BUFF_SIZE];
150 struct init_action *next;
154 /* Static variables */
155 static struct init_action *init_action_list = NULL;
156 static char console[CONSOLE_BUFF_SIZE] = _PATH_CONSOLE;
158 #ifndef CONFIG_SYSLOGD
159 static char *log = VC_5;
161 static sig_atomic_t got_cont = 0;
162 static const int LOG = 0x1;
163 static const int CONSOLE = 0x2;
165 #if defined CONFIG_FEATURE_EXTRA_QUIET
166 static const int MAYBE_CONSOLE = 0x0;
168 #define MAYBE_CONSOLE CONSOLE
170 #ifndef RB_HALT_SYSTEM
171 static const int RB_HALT_SYSTEM = 0xcdef0123;
172 static const int RB_ENABLE_CAD = 0x89abcdef;
173 static const int RB_DISABLE_CAD = 0;
175 #define RB_POWER_OFF 0x4321fedc
176 static const int RB_AUTOBOOT = 0x01234567;
179 static const char * const environment[] = {
181 "PATH=" _PATH_STDPATH,
187 /* Function prototypes */
188 static void delete_init_action(struct init_action *a);
189 static int waitfor(const struct init_action *a);
190 static void halt_signal(int sig);
193 static void loop_forever(void)
199 /* Print a message to the specified device.
200 * Device may be bitwise-or'd from LOG | CONSOLE */
202 static inline void messageD(int device, const char *fmt, ...)
206 #define messageD message
208 static void message(int device, const char *fmt, ...)
209 __attribute__ ((format(printf, 2, 3)));
210 static void message(int device, const char *fmt, ...)
215 #ifndef CONFIG_SYSLOGD
216 static int log_fd = -1;
220 va_start(arguments, fmt);
221 l = vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments) + 1;
224 #ifdef CONFIG_SYSLOGD
225 /* Log the message to syslogd */
227 /* don`t out "\r\n" */
228 openlog(bb_applet_name, 0, LOG_DAEMON);
229 syslog(LOG_INFO, "%s", msg);
239 /* Take full control of the log tty, and never close it.
240 * It's mine, all mine! Muhahahaha! */
242 if ((log_fd = device_open(log, O_RDWR | O_NDELAY | O_NOCTTY)) < 0) {
244 bb_error_msg("Bummer, can't write to log on %s!", log);
247 fcntl(log_fd, F_SETFD, FD_CLOEXEC);
250 if ((device & LOG) && (log_fd >= 0)) {
251 bb_full_write(log_fd, msg, l);
255 if (device & CONSOLE) {
256 int fd = device_open(_PATH_CONSOLE,
257 O_WRONLY | O_NOCTTY | O_NDELAY);
258 /* Always send console messages to /dev/console so people will see them. */
260 bb_full_write(fd, msg, l);
263 /* all descriptors may be closed */
265 bb_error_msg("Bummer, can't print: ");
266 va_start(arguments, fmt);
267 vfprintf(stderr, fmt, arguments);
274 /* Set terminal settings to reasonable defaults */
275 static void set_term(int fd)
281 /* set control chars */
282 tty.c_cc[VINTR] = 3; /* C-c */
283 tty.c_cc[VQUIT] = 28; /* C-\ */
284 tty.c_cc[VERASE] = 127; /* C-? */
285 tty.c_cc[VKILL] = 21; /* C-u */
286 tty.c_cc[VEOF] = 4; /* C-d */
287 tty.c_cc[VSTART] = 17; /* C-q */
288 tty.c_cc[VSTOP] = 19; /* C-s */
289 tty.c_cc[VSUSP] = 26; /* C-z */
291 /* use line dicipline 0 */
294 /* Make it be sane */
295 tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
296 tty.c_cflag |= CREAD | HUPCL | CLOCAL;
300 tty.c_iflag = ICRNL | IXON | IXOFF;
303 tty.c_oflag = OPOST | ONLCR;
307 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
309 tcsetattr(fd, TCSANOW, &tty);
312 /* How much memory does this machine have?
313 Units are kBytes to avoid overflow on 4GB machines */
314 static unsigned int check_free_memory(void)
317 unsigned int result, u, s = 10;
319 if (sysinfo(&info) != 0) {
320 bb_perror_msg("Error checking free memory");
324 /* Kernels 2.0.x and 2.2.x return info.mem_unit==0 with values in bytes.
325 * Kernels 2.4.0 return info.mem_unit in bytes. */
329 while ((u & 1) == 0 && s > 0) {
333 result = (info.totalram >> s) + (info.totalswap >> s);
334 if (((unsigned long long)result * (unsigned long long)u) > UINT_MAX) {
341 static void console_init(void)
346 struct serial_struct sr;
349 if ((s = getenv("CONSOLE")) != NULL || (s = getenv("console")) != NULL) {
350 safe_strncpy(console, s, sizeof(console));
352 /* sparc kernel supports console=tty[ab] parameter which is also
353 * passed to init, so catch it here */
354 /* remap tty[ab] to /dev/ttyS[01] */
355 if (strcmp(s, "ttya") == 0)
356 safe_strncpy(console, SC_0, sizeof(console));
357 else if (strcmp(s, "ttyb") == 0)
358 safe_strncpy(console, SC_1, sizeof(console));
361 /* 2.2 kernels: identify the real console backend and try to use it */
362 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
363 /* this is a serial console */
364 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
365 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
366 /* this is linux virtual tty */
367 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
369 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
374 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0 && tried < 2) {
375 /* Can't open selected console -- try
376 logical system console and VT_MASTER */
377 safe_strncpy(console, (tried == 0 ? _PATH_CONSOLE : CURRENT_VC),
382 /* Perhaps we should panic here? */
383 #ifndef CONFIG_SYSLOGD
386 safe_strncpy(console, "/dev/null", sizeof(console));
389 /* check for serial console */
390 if (ioctl(fd, TIOCGSERIAL, &sr) == 0) {
391 /* Force the TERM setting to vt102 for serial console --
392 * if TERM is set to linux (the default) */
393 if (s == NULL || strcmp(s, "linux") == 0)
394 putenv("TERM=vt102");
395 #ifndef CONFIG_SYSLOGD
400 putenv("TERM=linux");
404 messageD(LOG, "console=%s", console);
407 static void fixup_argv(int argc, char **argv, char *new_argv0)
411 /* Fix up argv[0] to be certain we claim to be init */
412 len = strlen(argv[0]);
413 memset(argv[0], 0, len);
414 safe_strncpy(argv[0], new_argv0, len + 1);
416 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
419 memset(argv[len], 0, strlen(argv[len]));
424 static pid_t run(const struct init_action *a)
428 pid_t pid, pgrp, tmp_pid;
429 char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
430 char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
431 sigset_t nmask, omask;
432 static const char press_enter[] =
433 #ifdef CUSTOMIZED_BANNER
434 #include CUSTOMIZED_BANNER
436 "\nPlease press Enter to activate this console. ";
438 /* Block sigchild while forking. */
440 sigaddset(&nmask, SIGCHLD);
441 sigprocmask(SIG_BLOCK, &nmask, &omask);
443 if ((pid = fork()) == 0) {
448 sigprocmask(SIG_SETMASK, &omask, NULL);
450 /* Reset signal handlers that were set by the parent process */
451 signal(SIGUSR1, SIG_DFL);
452 signal(SIGUSR2, SIG_DFL);
453 signal(SIGINT, SIG_DFL);
454 signal(SIGTERM, SIG_DFL);
455 signal(SIGHUP, SIG_DFL);
456 signal(SIGQUIT, SIG_DFL);
457 signal(SIGCONT, SIG_DFL);
458 signal(SIGSTOP, SIG_DFL);
459 signal(SIGTSTP, SIG_DFL);
461 /* Create a new session and make ourself the process
465 /* Open the new terminal device */
466 if ((device_open(a->terminal, O_RDWR)) < 0) {
467 if (stat(a->terminal, &sb) != 0) {
468 message(LOG | CONSOLE, "device '%s' does not exist.",
472 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
476 /* Make sure the terminal will act fairly normal for us */
478 /* Setup stdout, stderr for the new process so
479 * they point to the supplied terminal */
483 /* If the init Action requires us to wait, then force the
484 * supplied terminal to be the controlling tty. */
485 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
487 /* Now fork off another process to just hang around */
488 if ((pid = fork()) < 0) {
489 message(LOG | CONSOLE, "Can't fork!");
495 /* We are the parent -- wait till the child is done */
496 signal(SIGINT, SIG_IGN);
497 signal(SIGTSTP, SIG_IGN);
498 signal(SIGQUIT, SIG_IGN);
499 signal(SIGCHLD, SIG_DFL);
501 /* Wait for child to exit */
502 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
503 if (tmp_pid == -1 && errno == ECHILD) {
506 /* FIXME handle other errors */
509 /* See if stealing the controlling tty back is necessary */
511 if (pgrp != getpid())
514 /* Use a temporary process to steal the controlling tty. */
515 if ((pid = fork()) < 0) {
516 message(LOG | CONSOLE, "Can't fork!");
521 ioctl(0, TIOCSCTTY, 1);
524 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
525 if (tmp_pid < 0 && errno == ECHILD)
531 /* Now fall though to actually execute things */
534 /* See if any special /bin/sh requiring characters are present */
535 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
536 cmd[0] = (char *)DEFAULT_SHELL;
538 cmd[2] = strcat(strcpy(buf, "exec "), a->command);
541 /* Convert command (char*) into cmd (char**, one word per string) */
542 strcpy(buf, a->command);
544 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
545 if (*tmpCmd != '\0') {
556 Interactive shells want to see a dash in argv[0]. This
557 typically is handled by login, argv will be setup this
558 way if a dash appears at the front of the command path
562 if (*cmdpath == '-') {
564 /* skip over the dash */
567 /* find the last component in the command pathname */
568 s = bb_get_last_path_component(cmdpath);
570 /* make a new argv[0] */
571 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
572 message(LOG | CONSOLE, bb_msg_memory_exhausted);
576 strcpy(cmd[0] + 1, s);
580 #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
581 if (a->action & ASKFIRST) {
584 * Save memory by not exec-ing anything large (like a shell)
585 * before the user wants it. This is critical if swap is not
586 * enabled and the system has low memory. Generally this will
587 * be run on the second virtual console, and the first will
588 * be allowed to start a shell or whatever an init script
591 messageD(LOG, "Waiting for enter to start '%s'"
592 "(pid %d, terminal %s)\n",
593 cmdpath, getpid(), a->terminal);
594 bb_full_write(1, press_enter, sizeof(press_enter) - 1);
595 while(read(0, &c, 1) == 1 && c != '\n')
600 /* Log the process name and args */
601 message(LOG, "Starting pid %d, console %s: '%s'",
602 getpid(), a->terminal, cmdpath);
604 #if defined CONFIG_FEATURE_INIT_COREDUMPS
605 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
608 limit.rlim_cur = RLIM_INFINITY;
609 limit.rlim_max = RLIM_INFINITY;
610 setrlimit(RLIMIT_CORE, &limit);
614 /* Now run it. The new program will take over this PID,
615 * so nothing further in init.c should be run. */
618 /* We're still here? Some error happened. */
619 message(LOG | CONSOLE, "Bummer, could not run '%s': %m", cmdpath);
622 sigprocmask(SIG_SETMASK, &omask, NULL);
626 static int waitfor(const struct init_action *a)
633 wpid = waitpid(pid,&status,0);
636 if (wpid == -1 && errno == ECHILD) {
637 /* we missed its termination */
640 /* FIXME other errors should maybe trigger an error, but allow
641 * the program to continue */
646 /* Run all commands of a particular type */
647 static void run_actions(int action)
649 struct init_action *a, *tmp;
651 for (a = init_action_list; a; a = tmp) {
653 if (a->action == action) {
654 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
656 delete_init_action(a);
657 } else if (a->action & ONCE) {
659 delete_init_action(a);
660 } else if (a->action & (RESPAWN | ASKFIRST)) {
661 /* Only run stuff with pid==0. If they have
662 * a pid, that means it is still running */
672 static void init_reboot(unsigned long magic)
675 /* We have to fork here, since the kernel calls do_exit(0) in
676 * linux/kernel/sys.c, which can cause the machine to panic when
677 * the init process is killed.... */
678 if ((pid = fork()) == 0) {
682 waitpid (pid, NULL, 0);
685 static void shutdown_system(void)
687 sigset_t block_signals;
689 /* run everything to be run at "shutdown". This is done _prior_
690 * to killing everything, in case people wish to use scripts to
691 * shut things down gracefully... */
692 run_actions(SHUTDOWN);
694 /* first disable all our signals */
695 sigemptyset(&block_signals);
696 sigaddset(&block_signals, SIGHUP);
697 sigaddset(&block_signals, SIGQUIT);
698 sigaddset(&block_signals, SIGCHLD);
699 sigaddset(&block_signals, SIGUSR1);
700 sigaddset(&block_signals, SIGUSR2);
701 sigaddset(&block_signals, SIGINT);
702 sigaddset(&block_signals, SIGTERM);
703 sigaddset(&block_signals, SIGCONT);
704 sigaddset(&block_signals, SIGSTOP);
705 sigaddset(&block_signals, SIGTSTP);
706 sigprocmask(SIG_BLOCK, &block_signals, NULL);
708 /* Allow Ctrl-Alt-Del to reboot system. */
709 init_reboot(RB_ENABLE_CAD);
711 message(CONSOLE | LOG, "The system is going down NOW !!");
714 /* Send signals to every process _except_ pid 1 */
715 message(CONSOLE | LOG, "Sending SIGTERM to all processes.");
720 message(CONSOLE | LOG, "Sending SIGKILL to all processes.");
727 static void exec_signal(int sig)
729 struct init_action *a, *tmp;
730 sigset_t unblock_signals;
732 for (a = init_action_list; a; a = tmp) {
734 if (a->action & RESTART) {
739 /* unblock all signals, blocked in shutdown_system() */
740 sigemptyset(&unblock_signals);
741 sigaddset(&unblock_signals, SIGHUP);
742 sigaddset(&unblock_signals, SIGQUIT);
743 sigaddset(&unblock_signals, SIGCHLD);
744 sigaddset(&unblock_signals, SIGUSR1);
745 sigaddset(&unblock_signals, SIGUSR2);
746 sigaddset(&unblock_signals, SIGINT);
747 sigaddset(&unblock_signals, SIGTERM);
748 sigaddset(&unblock_signals, SIGCONT);
749 sigaddset(&unblock_signals, SIGSTOP);
750 sigaddset(&unblock_signals, SIGTSTP);
751 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
753 /* Close whatever files are open. */
758 /* Open the new terminal device */
759 if ((device_open(a->terminal, O_RDWR)) < 0) {
760 if (stat(a->terminal, &sb) != 0) {
761 message(LOG | CONSOLE, "device '%s' does not exist.", a->terminal);
763 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
765 halt_signal(SIGUSR1);
768 /* Make sure the terminal will act fairly normal for us */
770 /* Setup stdout, stderr on the supplied terminal */
774 messageD(CONSOLE | LOG, "Trying to re-exec %s", a->command);
775 execl(a->command, a->command, NULL);
777 message(CONSOLE | LOG, "exec of '%s' failed: %m",
781 init_reboot(RB_HALT_SYSTEM);
787 static void halt_signal(int sig)
790 message(CONSOLE | LOG,
792 /* Seems the s390 console is Wierd(tm). */
793 "The system is halted. You may reboot now."
795 "The system is halted. Press Reset or turn off power"
800 /* allow time for last message to reach serial console */
804 init_reboot(RB_POWER_OFF);
806 init_reboot(RB_HALT_SYSTEM);
811 static void reboot_signal(int sig)
814 message(CONSOLE | LOG, "Please stand by while rebooting the system.");
817 /* allow time for last message to reach serial console */
820 init_reboot(RB_AUTOBOOT);
825 static void ctrlaltdel_signal(int sig)
827 run_actions(CTRLALTDEL);
830 /* The SIGSTOP & SIGTSTP handler */
831 static void stop_handler(int sig)
833 int saved_errno = errno;
842 /* The SIGCONT handler */
843 static void cont_handler(int sig)
848 #endif /* ! DEBUG_INIT */
850 static void new_init_action(int action, const char *command, const char *cons)
852 struct init_action *new_action, *a, *last;
857 /* do not run entries if console device is not available */
858 if (access(cons, R_OK | W_OK))
860 if (strcmp(cons, "/dev/null") == 0 && (action & ASKFIRST))
863 new_action = calloc((size_t) (1), sizeof(struct init_action));
865 message(LOG | CONSOLE, "Memory allocation failure");
869 /* Append to the end of the list */
870 for (a = last = init_action_list; a; a = a->next) {
871 /* don't enter action if it's already in the list,
872 * but do overwrite existing actions */
873 if ((strcmp(a->command, command) == 0) &&
874 (strcmp(a->terminal, cons) ==0)) {
882 last->next = new_action;
884 init_action_list = new_action;
886 strcpy(new_action->command, command);
887 new_action->action = action;
888 strcpy(new_action->terminal, cons);
889 #if 0 /* calloc zeroed always */
892 messageD(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
893 new_action->command, new_action->action, new_action->terminal);
896 static void delete_init_action(struct init_action *action)
898 struct init_action *a, *b = NULL;
900 for (a = init_action_list; a; b = a, a = a->next) {
903 init_action_list = a->next;
913 /* Make sure there is enough memory to do something useful. *
914 * Calls "swapon -a" if needed so be sure /etc/fstab is present... */
915 static void check_memory(void)
919 if (check_free_memory() > 1000)
922 #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
923 if (stat("/etc/fstab", &statBuf) == 0) {
924 /* swapon -a requires /proc typically */
925 new_init_action(SYSINIT, "/bin/mount -t proc proc /proc", "");
926 /* Try to turn on swap */
927 new_init_action(SYSINIT, "/sbin/swapon -a", "");
928 run_actions(SYSINIT); /* wait and removing */
929 if (check_free_memory() < 1000)
937 message(CONSOLE, "Sorry, your computer does not have enough memory.");
941 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
942 * then parse_inittab() simply adds in some default
943 * actions(i.e., runs INIT_SCRIPT and then starts a pair
944 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
945 * _is_ defined, but /etc/inittab is missing, this
946 * results in the same set of default behaviors.
948 static void parse_inittab(void)
950 #ifdef CONFIG_FEATURE_USE_INITTAB
952 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
953 char tmpConsole[CONSOLE_BUFF_SIZE];
954 char *id, *runlev, *action, *command, *eol;
955 const struct init_action_type *a = actions;
958 file = fopen(INITTAB, "r");
960 /* No inittab file -- set up some default behavior */
962 /* Reboot on Ctrl-Alt-Del */
963 new_init_action(CTRLALTDEL, "/sbin/reboot", "");
964 /* Umount all filesystems on halt/reboot */
965 new_init_action(SHUTDOWN, "/bin/umount -a -r", "");
966 #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
967 /* Swapoff on halt/reboot */
968 new_init_action(SHUTDOWN, "/sbin/swapoff -a", "");
970 /* Prepare to restart init when a HUP is received */
971 new_init_action(RESTART, "/sbin/init", "");
972 /* Askfirst shell on tty1-4 */
973 new_init_action(ASKFIRST, bb_default_login_shell, "");
974 new_init_action(ASKFIRST, bb_default_login_shell, VC_2);
975 new_init_action(ASKFIRST, bb_default_login_shell, VC_3);
976 new_init_action(ASKFIRST, bb_default_login_shell, VC_4);
978 new_init_action(SYSINIT, INIT_SCRIPT, "");
981 #ifdef CONFIG_FEATURE_USE_INITTAB
984 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
985 /* Skip leading spaces */
986 for (id = buf; *id == ' ' || *id == '\t'; id++);
988 /* Skip the line if it's a comment */
989 if (*id == '#' || *id == '\n')
992 /* Trim the trailing \n */
993 eol = strrchr(id, '\n');
997 /* Keep a copy around for posterity's sake (and error msgs) */
998 strcpy(lineAsRead, buf);
1000 /* Separate the ID field from the runlevels */
1001 runlev = strchr(id, ':');
1002 if (runlev == NULL || *(runlev + 1) == '\0') {
1003 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1010 /* Separate the runlevels from the action */
1011 action = strchr(runlev, ':');
1012 if (action == NULL || *(action + 1) == '\0') {
1013 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1020 /* Separate the action from the command */
1021 command = strchr(action, ':');
1022 if (command == NULL || *(command + 1) == '\0') {
1023 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1030 /* Ok, now process it */
1031 for (a = actions; a->name != 0; a++) {
1032 if (strcmp(a->name, action) == 0) {
1034 if(strncmp(id, "/dev/", 5) == 0)
1036 strcpy(tmpConsole, "/dev/");
1037 safe_strncpy(tmpConsole + 5, id,
1038 CONSOLE_BUFF_SIZE - 5);
1041 new_init_action(a->action, command, id);
1046 /* Choke on an unknown action */
1047 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1052 #endif /* CONFIG_FEATURE_USE_INITTAB */
1055 #ifdef CONFIG_FEATURE_USE_INITTAB
1056 static void reload_signal(int sig)
1058 struct init_action *a, *tmp;
1060 message(LOG, "Reloading /etc/inittab");
1062 /* disable old entrys */
1063 for (a = init_action_list; a; a = a->next ) {
1069 /* remove unused entrys */
1070 for (a = init_action_list; a; a = tmp) {
1072 if (a->action & (ONCE | SYSINIT | WAIT ) &&
1074 delete_init_action(a);
1077 run_actions(RESPAWN);
1080 #endif /* CONFIG_FEATURE_USE_INITTAB */
1082 extern int init_main(int argc, char **argv)
1084 struct init_action *a;
1088 if (argc > 1 && !strcmp(argv[1], "-q")) {
1089 return kill_init(SIGHUP);
1092 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1094 #ifdef CONFIG_FEATURE_INITRD
1095 && strstr(bb_applet_name, "linuxrc") == NULL
1100 /* Set up sig handlers -- be sure to
1101 * clear all of these in run() */
1102 signal(SIGHUP, exec_signal);
1103 signal(SIGQUIT, exec_signal);
1104 signal(SIGUSR1, halt_signal);
1105 signal(SIGUSR2, halt_signal);
1106 signal(SIGINT, ctrlaltdel_signal);
1107 signal(SIGTERM, reboot_signal);
1108 signal(SIGCONT, cont_handler);
1109 signal(SIGSTOP, stop_handler);
1110 signal(SIGTSTP, stop_handler);
1112 /* Turn off rebooting via CTL-ALT-DEL -- we get a
1113 * SIGINT on CAD so we can shut things down gracefully... */
1114 init_reboot(RB_DISABLE_CAD);
1117 /* Figure out where the default console should be */
1120 /* Close whatever files are open, and reset the console. */
1125 if (device_open(console, O_RDWR | O_NOCTTY) == 0) {
1133 const char * const *e;
1134 /* Make sure environs is set to something sane */
1135 for(e = environment; *e; e++)
1136 putenv((char *) *e);
1139 message(MAYBE_CONSOLE | LOG, "init started: %s", bb_msg_full_version);
1141 /* Make sure there is enough memory to do something useful. */
1144 /* Check if we are supposed to be in single user mode */
1145 if (argc > 1 && (!strcmp(argv[1], "single") ||
1146 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1147 /* Start a shell on console */
1148 new_init_action(RESPAWN, bb_default_login_shell, "");
1150 /* Not in single user mode -- see what inittab says */
1152 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1153 * then parse_inittab() simply adds in some default
1154 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1155 * of "askfirst" shells */
1159 /* Make the command line just say "init" -- thats all, nothing else */
1160 fixup_argv(argc, argv, "init");
1162 /* Now run everything that needs to be run */
1164 /* First run the sysinit command */
1165 run_actions(SYSINIT);
1167 /* Next run anything that wants to block */
1170 /* Next run anything to be run only once */
1173 #ifdef CONFIG_FEATURE_USE_INITTAB
1174 /* Redefine SIGHUP to reread /etc/inittab */
1175 signal(SIGHUP, reload_signal);
1177 signal(SIGHUP, SIG_IGN);
1178 #endif /* CONFIG_FEATURE_USE_INITTAB */
1181 /* Now run the looping stuff for the rest of forever */
1183 /* run the respawn stuff */
1184 run_actions(RESPAWN);
1186 /* run the askfirst stuff */
1187 run_actions(ASKFIRST);
1189 /* Don't consume all CPU time -- sleep a bit */
1192 /* Wait for a child process to exit */
1193 wpid = wait(&status);
1195 /* Find out who died and clean up their corpse */
1196 for (a = init_action_list; a; a = a->next) {
1197 if (a->pid == wpid) {
1198 /* Set the pid to 0 so that the process gets
1199 * restarted by run_actions() */
1201 message(LOG, "Process '%s' (pid %d) exited. "
1202 "Scheduling it for restart.",
1206 /* see if anyone else is waiting to be reaped */
1207 wpid = waitpid (-1, &status, WNOHANG);
1214 c-file-style: "linux"