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) 1999-2002 by Erik Andersen <andersee@debian.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>
47 # include <sys/syslog.h>
49 #if (__GNU_LIBRARY__ > 5) || defined(__dietlibc__)
50 #include <sys/reboot.h>
54 #if defined(__UCLIBC__) && !defined(__UCLIBC_HAS_MMU__)
58 #define INIT_BUFFS_SIZE 256
60 /* From <linux/vt.h> */
62 unsigned short v_active; /* active vt */
63 unsigned short v_signal; /* signal to send */
64 unsigned short v_state; /* vt bitmask */
66 static const int VT_GETSTATE = 0x5603; /* get global vt state info */
68 /* From <linux/serial.h> */
69 struct serial_struct {
78 unsigned short close_delay;
79 char reserved_char[2];
81 unsigned short closing_wait; /* time to wait before closing */
82 unsigned short closing_wait2; /* no longer used... */
88 #define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
91 #if defined CONFIG_FEATURE_INIT_COREDUMPS
93 * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
94 * before processes are spawned to set core file size as unlimited.
95 * This is for debugging only. Don't use this is production, unless
96 * you want core dumps lying about....
98 #define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
99 #include <sys/resource.h>
100 #include <sys/time.h>
103 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
105 #if __GNU_LIBRARY__ > 5
106 #include <sys/kdaemon.h>
108 extern int bdflush(int func, long int data);
111 #define SHELL "/bin/sh" /* Default shell */
112 #define LOGIN_SHELL "-" SHELL /* Default login shell */
113 #define INITTAB "/etc/inittab" /* inittab file location */
115 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
118 #define MAXENV 16 /* Number of env. vars */
120 #define CONSOLE_BUFF_SIZE 32
122 /* Allowed init action types */
123 #define SYSINIT 0x001
124 #define RESPAWN 0x002
125 #define ASKFIRST 0x004
128 #define CTRLALTDEL 0x020
129 #define SHUTDOWN 0x040
130 #define RESTART 0x080
132 /* A mapping between "inittab" action name strings and action type codes. */
133 struct init_action_type {
138 static const struct init_action_type actions[] = {
139 {"sysinit", SYSINIT},
140 {"respawn", RESPAWN},
141 {"askfirst", ASKFIRST},
144 {"ctrlaltdel", CTRLALTDEL},
145 {"shutdown", SHUTDOWN},
146 {"restart", RESTART},
150 /* Set up a linked list of init_actions, to be read from inittab */
153 char command[INIT_BUFFS_SIZE];
154 char terminal[CONSOLE_BUFF_SIZE];
155 struct init_action *next;
159 /* Static variables */
160 static struct init_action *init_action_list = NULL;
161 static int kernelVersion;
162 static char console[CONSOLE_BUFF_SIZE] = _PATH_CONSOLE;
164 #ifndef CONFIG_SYSLOGD
165 static char *log = VC_5;
167 static sig_atomic_t got_cont = 0;
168 static const int LOG = 0x1;
169 static const int CONSOLE = 0x2;
171 #if defined CONFIG_FEATURE_EXTRA_QUIET
172 static const int MAYBE_CONSOLE = 0x0;
174 #define MAYBE_CONSOLE CONSOLE
176 #ifndef RB_HALT_SYSTEM
177 static const int RB_HALT_SYSTEM = 0xcdef0123;
178 static const int RB_ENABLE_CAD = 0x89abcdef;
179 static const int RB_DISABLE_CAD = 0;
181 #define RB_POWER_OFF 0x4321fedc
182 static const int RB_AUTOBOOT = 0x01234567;
185 static const char * const environment[] = {
187 "PATH=" _PATH_STDPATH,
193 /* Function prototypes */
194 static void delete_init_action(struct init_action *a);
195 static int waitfor(const struct init_action *a);
198 static void loop_forever(void)
204 /* Print a message to the specified device.
205 * Device may be bitwise-or'd from LOG | CONSOLE */
207 static inline void messageD(int device, const char *fmt, ...)
211 #define messageD message
213 static void message(int device, const char *fmt, ...)
214 __attribute__ ((format(printf, 2, 3)));
215 static void message(int device, const char *fmt, ...)
220 #ifndef CONFIG_SYSLOGD
221 static int log_fd = -1;
225 va_start(arguments, fmt);
226 l = vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments) + 1;
229 #ifdef CONFIG_SYSLOGD
230 /* Log the message to syslogd */
232 /* don`t out "\r\n" */
233 syslog_msg(LOG_DAEMON, LOG_INFO, msg + 1);
242 /* Take full control of the log tty, and never close it.
243 * It's mine, all mine! Muhahahaha! */
245 if ((log_fd = device_open(log, O_RDWR | O_NDELAY | O_NOCTTY)) < 0) {
247 bb_error_msg("Bummer, can't write to log on %s!", log);
250 fcntl(log_fd, F_SETFD, FD_CLOEXEC);
253 if ((device & LOG) && (log_fd >= 0)) {
254 bb_full_write(log_fd, msg, l);
258 if (device & CONSOLE) {
259 int fd = device_open(_PATH_CONSOLE,
260 O_WRONLY | O_NOCTTY | O_NDELAY);
261 /* Always send console messages to /dev/console so people will see them. */
263 bb_full_write(fd, msg, l);
266 /* all descriptors may be closed */
268 bb_error_msg("Bummer, can't print: ");
269 va_start(arguments, fmt);
270 vfprintf(stderr, fmt, arguments);
277 /* Set terminal settings to reasonable defaults */
278 static void set_term(int fd)
284 /* set control chars */
285 tty.c_cc[VINTR] = 3; /* C-c */
286 tty.c_cc[VQUIT] = 28; /* C-\ */
287 tty.c_cc[VERASE] = 127; /* C-? */
288 tty.c_cc[VKILL] = 21; /* C-u */
289 tty.c_cc[VEOF] = 4; /* C-d */
290 tty.c_cc[VSTART] = 17; /* C-q */
291 tty.c_cc[VSTOP] = 19; /* C-s */
292 tty.c_cc[VSUSP] = 26; /* C-z */
294 /* use line dicipline 0 */
297 /* Make it be sane */
298 tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
299 tty.c_cflag |= CREAD | HUPCL | CLOCAL;
303 tty.c_iflag = ICRNL | IXON | IXOFF;
306 tty.c_oflag = OPOST | ONLCR;
310 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
312 tcsetattr(fd, TCSANOW, &tty);
315 /* How much memory does this machine have?
316 Units are kBytes to avoid overflow on 4GB machines */
317 static int check_free_memory(void)
320 unsigned int result, u, s = 10;
322 if (sysinfo(&info) != 0) {
323 bb_perror_msg("Error checking free memory");
327 /* Kernels 2.0.x and 2.2.x return info.mem_unit==0 with values in bytes.
328 * Kernels 2.4.0 return info.mem_unit in bytes. */
332 while ((u & 1) == 0 && s > 0) {
336 result = (info.totalram >> s) + (info.totalswap >> s);
343 static void console_init(void)
348 struct serial_struct sr;
351 if ((s = getenv("CONSOLE")) != NULL || (s = getenv("console")) != NULL) {
352 safe_strncpy(console, s, sizeof(console));
354 /* sparc kernel supports console=tty[ab] parameter which is also
355 * passed to init, so catch it here */
356 /* remap tty[ab] to /dev/ttyS[01] */
357 if (strcmp(s, "ttya") == 0)
358 safe_strncpy(console, SC_0, sizeof(console));
359 else if (strcmp(s, "ttyb") == 0)
360 safe_strncpy(console, SC_1, sizeof(console));
363 /* 2.2 kernels: identify the real console backend and try to use it */
364 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
365 /* this is a serial console */
366 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
367 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
368 /* this is linux virtual tty */
369 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
371 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
376 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0 && tried < 2) {
377 /* Can't open selected console -- try
378 logical system console and VT_MASTER */
379 safe_strncpy(console, (tried == 0 ? _PATH_CONSOLE : CURRENT_VC),
384 /* Perhaps we should panic here? */
385 #ifndef CONFIG_SYSLOGD
388 safe_strncpy(console, "/dev/null", sizeof(console));
391 /* check for serial console */
392 if (ioctl(fd, TIOCGSERIAL, &sr) == 0) {
393 /* Force the TERM setting to vt102 for serial console --
394 * if TERM is set to linux (the default) */
395 if (s == NULL || strcmp(s, "linux") == 0)
396 putenv("TERM=vt102");
397 #ifndef CONFIG_SYSLOGD
402 putenv("TERM=linux");
406 messageD(LOG, "console=%s", console);
409 static void fixup_argv(int argc, char **argv, char *new_argv0)
413 /* Fix up argv[0] to be certain we claim to be init */
414 len = strlen(argv[0]);
415 memset(argv[0], 0, len);
416 safe_strncpy(argv[0], new_argv0, len + 1);
418 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
421 memset(argv[len], 0, strlen(argv[len]));
426 static pid_t run(const struct init_action *a)
430 pid_t pid, pgrp, tmp_pid;
431 char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
432 char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
433 sigset_t nmask, omask;
434 static const char press_enter[] =
435 #ifdef CUSTOMIZED_BANNER
436 #include CUSTOMIZED_BANNER
438 "\nPlease press Enter to activate this console. ";
440 /* Block sigchild while forking. */
442 sigaddset(&nmask, SIGCHLD);
443 sigprocmask(SIG_BLOCK, &nmask, &omask);
445 if ((pid = fork()) == 0) {
450 sigprocmask(SIG_SETMASK, &omask, NULL);
452 /* Reset signal handlers that were set by the parent process */
453 signal(SIGUSR1, SIG_DFL);
454 signal(SIGUSR2, SIG_DFL);
455 signal(SIGINT, SIG_DFL);
456 signal(SIGTERM, SIG_DFL);
457 signal(SIGHUP, SIG_DFL);
458 signal(SIGCONT, SIG_DFL);
459 signal(SIGSTOP, SIG_DFL);
460 signal(SIGTSTP, SIG_DFL);
462 /* Create a new session and make ourself the process
466 /* Open the new terminal device */
467 if ((device_open(a->terminal, O_RDWR)) < 0) {
468 if (stat(a->terminal, &sb) != 0) {
469 message(LOG | CONSOLE, "device '%s' does not exist.",
473 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
477 /* Make sure the terminal will act fairly normal for us */
479 /* Setup stdout, stderr for the new process so
480 * they point to the supplied terminal */
484 /* If the init Action requires us to wait, then force the
485 * supplied terminal to be the controlling tty. */
486 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
488 /* Now fork off another process to just hang around */
489 if ((pid = fork()) < 0) {
490 message(LOG | CONSOLE, "Can't fork!");
496 /* We are the parent -- wait till the child is done */
497 signal(SIGINT, SIG_IGN);
498 signal(SIGTSTP, SIG_IGN);
499 signal(SIGQUIT, SIG_IGN);
500 signal(SIGCHLD, SIG_DFL);
502 /* Wait for child to exit */
503 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid);
505 /* See if stealing the controlling tty back is necessary */
507 if (pgrp != getpid())
510 /* Use a temporary process to steal the controlling tty. */
511 if ((pid = fork()) < 0) {
512 message(LOG | CONSOLE, "Can't fork!");
517 ioctl(0, TIOCSCTTY, 1);
520 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
521 if (tmp_pid < 0 && errno == ECHILD)
527 /* Now fall though to actually execute things */
530 /* See if any special /bin/sh requiring characters are present */
531 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
534 cmd[2] = strcat(strcpy(buf, "exec "), a->command);
537 /* Convert command (char*) into cmd (char**, one word per string) */
538 strcpy(buf, a->command);
540 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
541 if (*tmpCmd != '\0') {
552 Interactive shells want to see a dash in argv[0]. This
553 typically is handled by login, argv will be setup this
554 way if a dash appears at the front of the command path
558 if (*cmdpath == '-') {
560 /* skip over the dash */
563 /* find the last component in the command pathname */
564 s = bb_get_last_path_component(cmdpath);
566 /* make a new argv[0] */
567 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
568 message(LOG | CONSOLE, bb_msg_memory_exhausted);
572 strcpy(cmd[0] + 1, s);
576 if (a->action & ASKFIRST) {
579 * Save memory by not exec-ing anything large (like a shell)
580 * before the user wants it. This is critical if swap is not
581 * enabled and the system has low memory. Generally this will
582 * be run on the second virtual console, and the first will
583 * be allowed to start a shell or whatever an init script
586 messageD(LOG, "Waiting for enter to start '%s'"
587 "(pid %d, terminal %s)\n",
588 cmdpath, getpid(), a->terminal);
589 bb_full_write(1, press_enter, sizeof(press_enter) - 1);
590 while(read(0, &c, 1) == 1 && c != '\n')
594 /* Log the process name and args */
595 message(LOG, "Starting pid %d, console %s: '%s'",
596 getpid(), a->terminal, cmdpath);
598 #if defined CONFIG_FEATURE_INIT_COREDUMPS
599 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
602 limit.rlim_cur = RLIM_INFINITY;
603 limit.rlim_max = RLIM_INFINITY;
604 setrlimit(RLIMIT_CORE, &limit);
608 /* Now run it. The new program will take over this PID,
609 * so nothing further in init.c should be run. */
612 /* We're still here? Some error happened. */
613 message(LOG | CONSOLE, "Bummer, could not run '%s': %m", cmdpath);
616 sigprocmask(SIG_SETMASK, &omask, NULL);
620 static int waitfor(const struct init_action *a)
627 wpid = wait(&status);
628 if (wpid > 0 && wpid != pid) {
637 /* Run all commands of a particular type */
638 static void run_actions(int action)
640 struct init_action *a, *tmp;
642 for (a = init_action_list; a; a = tmp) {
644 if (a->action == action) {
645 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
647 delete_init_action(a);
648 } else if (a->action & ONCE) {
650 delete_init_action(a);
651 } else if (a->action & (RESPAWN | ASKFIRST)) {
652 /* Only run stuff with pid==0. If they have
653 * a pid, that means it is still running */
663 static void init_reboot(unsigned long magic)
666 /* We have to fork here, since the kernel calls do_exit(0) in
667 * linux/kernel/sys.c, which can cause the machint to panic when
668 * the init process is killed.... */
669 if ((pid = fork()) == 0) {
670 #if (__GNU_LIBRARY__ > 5) || defined(__dietlibc__)
673 reboot(0xfee1dead, 672274793, magic);
677 waitpid (pid, NULL, 0);
680 static void shutdown_system(void)
682 sigset_t block_signals;
684 /* run everything to be run at "shutdown". This is done _prior_
685 * to killing everything, in case people wish to use scripts to
686 * shut things down gracefully... */
687 run_actions(SHUTDOWN);
689 /* first disable all our signals */
690 sigemptyset(&block_signals);
691 sigaddset(&block_signals, SIGHUP);
692 sigaddset(&block_signals, SIGCHLD);
693 sigaddset(&block_signals, SIGUSR1);
694 sigaddset(&block_signals, SIGUSR2);
695 sigaddset(&block_signals, SIGINT);
696 sigaddset(&block_signals, SIGTERM);
697 sigaddset(&block_signals, SIGCONT);
698 sigaddset(&block_signals, SIGSTOP);
699 sigaddset(&block_signals, SIGTSTP);
700 sigprocmask(SIG_BLOCK, &block_signals, NULL);
702 /* Allow Ctrl-Alt-Del to reboot system. */
703 init_reboot(RB_ENABLE_CAD);
705 message(CONSOLE | LOG, "The system is going down NOW !!");
708 /* Send signals to every process _except_ pid 1 */
709 message(CONSOLE | LOG, "Sending SIGTERM to all processes.");
714 message(CONSOLE | LOG, "Sending SIGKILL to all processes.");
719 if (kernelVersion > 0 && kernelVersion <= KERNEL_VERSION(2, 2, 11)) {
720 /* bdflush, kupdate not needed for kernels >2.2.11 */
726 static void exec_signal(int sig)
728 struct init_action *a, *tmp;
729 sigset_t unblock_signals;
731 for (a = init_action_list; a; a = tmp) {
733 if (a->action & RESTART) {
736 /* unblock all signals, blocked in shutdown_system() */
737 sigemptyset(&unblock_signals);
738 sigaddset(&unblock_signals, SIGHUP);
739 sigaddset(&unblock_signals, SIGCHLD);
740 sigaddset(&unblock_signals, SIGUSR1);
741 sigaddset(&unblock_signals, SIGUSR2);
742 sigaddset(&unblock_signals, SIGINT);
743 sigaddset(&unblock_signals, SIGTERM);
744 sigaddset(&unblock_signals, SIGCONT);
745 sigaddset(&unblock_signals, SIGSTOP);
746 sigaddset(&unblock_signals, SIGTSTP);
747 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
749 messageD(CONSOLE | LOG, "Trying to re-exec %s", a->command);
750 execl(a->command, a->command, NULL);
752 message(CONSOLE | LOG, "exec of '%s' failed: %m",
756 init_reboot(RB_HALT_SYSTEM);
762 static void halt_signal(int sig)
765 message(CONSOLE | LOG,
767 /* Seems the s390 console is Wierd(tm). */
768 "The system is halted. You may reboot now."
770 "The system is halted. Press Reset or turn off power"
775 /* allow time for last message to reach serial console */
778 if (sig == SIGUSR2 && kernelVersion >= KERNEL_VERSION(2, 2, 0))
779 init_reboot(RB_POWER_OFF);
781 init_reboot(RB_HALT_SYSTEM);
786 static void reboot_signal(int sig)
789 message(CONSOLE | LOG, "Please stand by while rebooting the system.");
792 /* allow time for last message to reach serial console */
795 init_reboot(RB_AUTOBOOT);
800 static void ctrlaltdel_signal(int sig)
802 run_actions(CTRLALTDEL);
805 /* The SIGSTOP & SIGTSTP handler */
806 static void stop_handler(int sig)
808 int saved_errno = errno;
817 /* The SIGCONT handler */
818 static void cont_handler(int sig)
823 #endif /* ! DEBUG_INIT */
825 static void new_init_action(int action, char *command, const char *cons)
827 struct init_action *new_action, *a;
832 /* do not run entries if console device is not available */
833 if (access(cons, R_OK | W_OK))
835 if (strcmp(cons, "/dev/null") == 0 && (action & ASKFIRST))
838 new_action = calloc((size_t) (1), sizeof(struct init_action));
840 message(LOG | CONSOLE, "Memory allocation failure");
844 /* Append to the end of the list */
845 for (a = init_action_list; a && a->next; a = a->next);
847 a->next = new_action;
849 init_action_list = new_action;
851 strcpy(new_action->command, command);
852 new_action->action = action;
853 strcpy(new_action->terminal, cons);
854 #if 0 /* calloc zeroed always */
857 messageD(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
858 new_action->command, new_action->action, new_action->terminal);
861 static void delete_init_action(struct init_action *action)
863 struct init_action *a, *b = NULL;
865 for (a = init_action_list; a; b = a, a = a->next) {
868 init_action_list = a->next;
878 /* Make sure there is enough memory to do something useful. *
879 * Calls "swapon -a" if needed so be sure /etc/fstab is present... */
880 static void check_memory(void)
884 if (check_free_memory() > 1000)
887 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
888 if (stat("/etc/fstab", &statBuf) == 0) {
889 /* swapon -a requires /proc typically */
890 new_init_action(SYSINIT, "/bin/mount -t proc proc /proc", "");
891 /* Try to turn on swap */
892 new_init_action(SYSINIT, "/sbin/swapon -a", "");
893 run_actions(SYSINIT); /* wait and removing */
894 if (check_free_memory() < 1000)
902 message(CONSOLE, "Sorry, your computer does not have enough memory.");
906 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
907 * then parse_inittab() simply adds in some default
908 * actions(i.e., runs INIT_SCRIPT and then starts a pair
909 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
910 * _is_ defined, but /etc/inittab is missing, this
911 * results in the same set of default behaviors.
913 static void parse_inittab(void)
915 #ifdef CONFIG_FEATURE_USE_INITTAB
917 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
918 char tmpConsole[CONSOLE_BUFF_SIZE];
919 char *id, *runlev, *action, *command, *eol;
920 const struct init_action_type *a = actions;
923 file = fopen(INITTAB, "r");
925 /* No inittab file -- set up some default behavior */
927 /* Reboot on Ctrl-Alt-Del */
928 new_init_action(CTRLALTDEL, "/sbin/reboot", "");
929 /* Umount all filesystems on halt/reboot */
930 new_init_action(SHUTDOWN, "/bin/umount -a -r", "");
931 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
932 /* Swapoff on halt/reboot */
933 new_init_action(SHUTDOWN, "/sbin/swapoff -a", "");
935 /* Prepare to restart init when a HUP is received */
936 new_init_action(RESTART, "/sbin/init", "");
937 /* Askfirst shell on tty1-4 */
938 new_init_action(ASKFIRST, LOGIN_SHELL, "");
939 new_init_action(ASKFIRST, LOGIN_SHELL, VC_2);
940 new_init_action(ASKFIRST, LOGIN_SHELL, VC_3);
941 new_init_action(ASKFIRST, LOGIN_SHELL, VC_4);
943 new_init_action(SYSINIT, INIT_SCRIPT, "");
946 #ifdef CONFIG_FEATURE_USE_INITTAB
949 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
950 /* Skip leading spaces */
951 for (id = buf; *id == ' ' || *id == '\t'; id++);
953 /* Skip the line if it's a comment */
954 if (*id == '#' || *id == '\n')
957 /* Trim the trailing \n */
958 eol = strrchr(id, '\n');
962 /* Keep a copy around for posterity's sake (and error msgs) */
963 strcpy(lineAsRead, buf);
965 /* Separate the ID field from the runlevels */
966 runlev = strchr(id, ':');
967 if (runlev == NULL || *(runlev + 1) == '\0') {
968 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
975 /* Separate the runlevels from the action */
976 action = strchr(runlev, ':');
977 if (action == NULL || *(action + 1) == '\0') {
978 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
985 /* Separate the action from the command */
986 command = strchr(action, ':');
987 if (command == NULL || *(command + 1) == '\0') {
988 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
995 /* Ok, now process it */
996 for (a = actions; a->name != 0; a++) {
997 if (strcmp(a->name, action) == 0) {
999 if(strncmp(id, "/dev/", 5) == 0)
1001 strcpy(tmpConsole, "/dev/");
1002 safe_strncpy(tmpConsole + 5, id,
1003 CONSOLE_BUFF_SIZE - 5);
1006 new_init_action(a->action, command, id);
1011 /* Choke on an unknown action */
1012 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1017 #endif /* CONFIG_FEATURE_USE_INITTAB */
1021 extern int init_main(int argc, char **argv)
1023 struct init_action *a;
1027 if (argc > 1 && !strcmp(argv[1], "-q")) {
1028 /* don't assume init's pid == 1 */
1029 long *pid = find_pid_by_name("init");
1031 if (!pid || *pid <= 0) {
1032 pid = find_pid_by_name("linuxrc");
1033 if (!pid || *pid <= 0)
1034 bb_error_msg_and_die("no process killed");
1036 return kill(*pid, SIGHUP);
1039 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1041 #ifdef CONFIG_FEATURE_INITRD
1042 && strstr(bb_applet_name, "linuxrc") == NULL
1047 /* Set up sig handlers -- be sure to
1048 * clear all of these in run() */
1049 signal(SIGHUP, exec_signal);
1050 signal(SIGUSR1, halt_signal);
1051 signal(SIGUSR2, halt_signal);
1052 signal(SIGINT, ctrlaltdel_signal);
1053 signal(SIGTERM, reboot_signal);
1054 signal(SIGCONT, cont_handler);
1055 signal(SIGSTOP, stop_handler);
1056 signal(SIGTSTP, stop_handler);
1058 /* Turn off rebooting via CTL-ALT-DEL -- we get a
1059 * SIGINT on CAD so we can shut things down gracefully... */
1060 init_reboot(RB_DISABLE_CAD);
1063 /* Figure out what kernel this is running */
1064 kernelVersion = get_kernel_revision();
1066 /* Figure out where the default console should be */
1069 /* Close whatever files are open, and reset the console. */
1074 if (device_open(console, O_RDWR | O_NOCTTY) == 0) {
1082 const char * const *e;
1083 /* Make sure environs is set to something sane */
1084 for(e = environment; *e; e++)
1085 putenv((char *) *e);
1088 message(MAYBE_CONSOLE | LOG, "init started: %s", bb_msg_full_version);
1090 /* Make sure there is enough memory to do something useful. */
1093 /* Check if we are supposed to be in single user mode */
1094 if (argc > 1 && (!strcmp(argv[1], "single") ||
1095 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1096 /* Start a shell on console */
1097 new_init_action(RESPAWN, LOGIN_SHELL, "");
1099 /* Not in single user mode -- see what inittab says */
1101 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1102 * then parse_inittab() simply adds in some default
1103 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1104 * of "askfirst" shells */
1108 /* Make the command line just say "init" -- thats all, nothing else */
1109 fixup_argv(argc, argv, "init");
1111 /* Now run everything that needs to be run */
1113 /* First run the sysinit command */
1114 run_actions(SYSINIT);
1116 /* Next run anything that wants to block */
1119 /* Next run anything to be run only once */
1122 /* If there is nothing else to do, stop */
1123 if (init_action_list == NULL) {
1124 message(LOG | CONSOLE,
1125 "No more tasks for init -- sleeping forever.");
1129 /* Now run the looping stuff for the rest of forever */
1131 /* run the respawn stuff */
1132 run_actions(RESPAWN);
1134 /* run the askfirst stuff */
1135 run_actions(ASKFIRST);
1137 /* Don't consume all CPU time -- sleep a bit */
1140 /* Wait for a child process to exit */
1141 wpid = wait(&status);
1143 /* Find out who died and clean up their corpse */
1144 for (a = init_action_list; a; a = a->next) {
1145 if (a->pid == wpid) {
1146 /* Set the pid to 0 so that the process gets
1147 * restarted by run_actions() */
1149 message(LOG, "Process '%s' (pid %d) exited. "
1150 "Scheduling it for restart.",
1154 /* see if anyone else is waiting to be reaped */
1155 wpid = waitpid (-1, &status, WNOHANG);
1162 c-file-style: "linux"