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) 1999-2003 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 #if defined(__UCLIBC__) && !defined(__UCLIBC_HAS_MMU__)
60 #define INIT_BUFFS_SIZE 256
62 /* From <linux/vt.h> */
64 unsigned short v_active; /* active vt */
65 unsigned short v_signal; /* signal to send */
66 unsigned short v_state; /* vt bitmask */
68 static const int VT_GETSTATE = 0x5603; /* get global vt state info */
70 /* From <linux/serial.h> */
71 struct serial_struct {
80 unsigned short close_delay;
82 char reserved_char[1];
84 unsigned short closing_wait; /* time to wait before closing */
85 unsigned short closing_wait2; /* no longer used... */
86 unsigned char *iomem_base;
87 unsigned short iomem_reg_shift;
88 unsigned int port_high;
89 unsigned long iomap_base; /* cookie passed into ioremap */
95 #define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
98 #if defined CONFIG_FEATURE_INIT_COREDUMPS
100 * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
101 * before processes are spawned to set core file size as unlimited.
102 * This is for debugging only. Don't use this is production, unless
103 * you want core dumps lying about....
105 #define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
106 #include <sys/resource.h>
107 #include <sys/time.h>
110 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
112 #define INITTAB "/etc/inittab" /* inittab file location */
114 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
117 #define MAXENV 16 /* Number of env. vars */
119 #define CONSOLE_BUFF_SIZE 32
121 /* Allowed init action types */
122 #define SYSINIT 0x001
123 #define RESPAWN 0x002
124 #define ASKFIRST 0x004
127 #define CTRLALTDEL 0x020
128 #define SHUTDOWN 0x040
129 #define RESTART 0x080
131 /* A mapping between "inittab" action name strings and action type codes. */
132 struct init_action_type {
137 static const struct init_action_type actions[] = {
138 {"sysinit", SYSINIT},
139 {"respawn", RESPAWN},
140 {"askfirst", ASKFIRST},
143 {"ctrlaltdel", CTRLALTDEL},
144 {"shutdown", SHUTDOWN},
145 {"restart", RESTART},
149 /* Set up a linked list of init_actions, to be read from inittab */
152 char command[INIT_BUFFS_SIZE];
153 char terminal[CONSOLE_BUFF_SIZE];
154 struct init_action *next;
158 /* Static variables */
159 static struct init_action *init_action_list = NULL;
160 static char console[CONSOLE_BUFF_SIZE] = _PATH_CONSOLE;
162 #ifndef CONFIG_SYSLOGD
163 static char *log = VC_5;
165 static sig_atomic_t got_cont = 0;
166 static const int LOG = 0x1;
167 static const int CONSOLE = 0x2;
169 #if defined CONFIG_FEATURE_EXTRA_QUIET
170 static const int MAYBE_CONSOLE = 0x0;
172 #define MAYBE_CONSOLE CONSOLE
174 #ifndef RB_HALT_SYSTEM
175 static const int RB_HALT_SYSTEM = 0xcdef0123;
176 static const int RB_ENABLE_CAD = 0x89abcdef;
177 static const int RB_DISABLE_CAD = 0;
179 #define RB_POWER_OFF 0x4321fedc
180 static const int RB_AUTOBOOT = 0x01234567;
183 static const char * const environment[] = {
185 "PATH=" _PATH_STDPATH,
191 /* Function prototypes */
192 static void delete_init_action(struct init_action *a);
193 static int waitfor(const struct init_action *a);
194 static void halt_signal(int sig);
197 static void loop_forever(void)
203 /* Print a message to the specified device.
204 * Device may be bitwise-or'd from LOG | CONSOLE */
206 static inline void messageD(int device, const char *fmt, ...)
210 #define messageD message
212 static void message(int device, const char *fmt, ...)
213 __attribute__ ((format(printf, 2, 3)));
214 static void message(int device, const char *fmt, ...)
219 #ifndef CONFIG_SYSLOGD
220 static int log_fd = -1;
224 va_start(arguments, fmt);
225 l = vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments) + 1;
228 #ifdef CONFIG_SYSLOGD
229 /* Log the message to syslogd */
231 /* don`t out "\r\n" */
232 syslog_msg(LOG_DAEMON, LOG_INFO, msg + 1);
241 /* Take full control of the log tty, and never close it.
242 * It's mine, all mine! Muhahahaha! */
244 if ((log_fd = device_open(log, O_RDWR | O_NDELAY | O_NOCTTY)) < 0) {
246 bb_error_msg("Bummer, can't write to log on %s!", log);
249 fcntl(log_fd, F_SETFD, FD_CLOEXEC);
252 if ((device & LOG) && (log_fd >= 0)) {
253 bb_full_write(log_fd, msg, l);
257 if (device & CONSOLE) {
258 int fd = device_open(_PATH_CONSOLE,
259 O_WRONLY | O_NOCTTY | O_NDELAY);
260 /* Always send console messages to /dev/console so people will see them. */
262 bb_full_write(fd, msg, l);
265 /* all descriptors may be closed */
267 bb_error_msg("Bummer, can't print: ");
268 va_start(arguments, fmt);
269 vfprintf(stderr, fmt, arguments);
276 /* Set terminal settings to reasonable defaults */
277 static void set_term(int fd)
283 /* set control chars */
284 tty.c_cc[VINTR] = 3; /* C-c */
285 tty.c_cc[VQUIT] = 28; /* C-\ */
286 tty.c_cc[VERASE] = 127; /* C-? */
287 tty.c_cc[VKILL] = 21; /* C-u */
288 tty.c_cc[VEOF] = 4; /* C-d */
289 tty.c_cc[VSTART] = 17; /* C-q */
290 tty.c_cc[VSTOP] = 19; /* C-s */
291 tty.c_cc[VSUSP] = 26; /* C-z */
293 /* use line dicipline 0 */
296 /* Make it be sane */
297 tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
298 tty.c_cflag |= CREAD | HUPCL | CLOCAL;
302 tty.c_iflag = ICRNL | IXON | IXOFF;
305 tty.c_oflag = OPOST | ONLCR;
309 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
311 tcsetattr(fd, TCSANOW, &tty);
314 /* How much memory does this machine have?
315 Units are kBytes to avoid overflow on 4GB machines */
316 static unsigned int check_free_memory(void)
319 unsigned int result, u, s = 10;
321 if (sysinfo(&info) != 0) {
322 bb_perror_msg("Error checking free memory");
326 /* Kernels 2.0.x and 2.2.x return info.mem_unit==0 with values in bytes.
327 * Kernels 2.4.0 return info.mem_unit in bytes. */
331 while ((u & 1) == 0 && s > 0) {
335 result = (info.totalram >> s) + (info.totalswap >> s);
336 if (((unsigned long long)result * (unsigned long long)u) > UINT_MAX) {
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) {
504 if (tmp_pid == -1 && errno == ECHILD) {
507 /* FIXME handle other errors */
510 /* See if stealing the controlling tty back is necessary */
512 if (pgrp != getpid())
515 /* Use a temporary process to steal the controlling tty. */
516 if ((pid = fork()) < 0) {
517 message(LOG | CONSOLE, "Can't fork!");
522 ioctl(0, TIOCSCTTY, 1);
525 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
526 if (tmp_pid < 0 && errno == ECHILD)
532 /* Now fall though to actually execute things */
535 /* See if any special /bin/sh requiring characters are present */
536 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
537 cmd[0] = (char *)DEFAULT_SHELL;
539 cmd[2] = strcat(strcpy(buf, "exec "), a->command);
542 /* Convert command (char*) into cmd (char**, one word per string) */
543 strcpy(buf, a->command);
545 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
546 if (*tmpCmd != '\0') {
557 Interactive shells want to see a dash in argv[0]. This
558 typically is handled by login, argv will be setup this
559 way if a dash appears at the front of the command path
563 if (*cmdpath == '-') {
565 /* skip over the dash */
568 /* find the last component in the command pathname */
569 s = bb_get_last_path_component(cmdpath);
571 /* make a new argv[0] */
572 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
573 message(LOG | CONSOLE, bb_msg_memory_exhausted);
577 strcpy(cmd[0] + 1, s);
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')
599 /* Log the process name and args */
600 message(LOG, "Starting pid %d, console %s: '%s'",
601 getpid(), a->terminal, cmdpath);
603 #if defined CONFIG_FEATURE_INIT_COREDUMPS
604 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
607 limit.rlim_cur = RLIM_INFINITY;
608 limit.rlim_max = RLIM_INFINITY;
609 setrlimit(RLIMIT_CORE, &limit);
613 /* Now run it. The new program will take over this PID,
614 * so nothing further in init.c should be run. */
617 /* We're still here? Some error happened. */
618 message(LOG | CONSOLE, "Bummer, could not run '%s': %m", cmdpath);
621 sigprocmask(SIG_SETMASK, &omask, NULL);
625 static int waitfor(const struct init_action *a)
632 wpid = waitpid(pid,&status,0);
635 if (wpid == -1 && errno == ECHILD) {
636 /* we missed its termination */
639 /* FIXME other errors should maybe trigger an error, but allow
640 * the program to continue */
645 /* Run all commands of a particular type */
646 static void run_actions(int action)
648 struct init_action *a, *tmp;
650 for (a = init_action_list; a; a = tmp) {
652 if (a->action == action) {
653 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
655 delete_init_action(a);
656 } else if (a->action & ONCE) {
658 delete_init_action(a);
659 } else if (a->action & (RESPAWN | ASKFIRST)) {
660 /* Only run stuff with pid==0. If they have
661 * a pid, that means it is still running */
671 static void init_reboot(unsigned long magic)
674 /* We have to fork here, since the kernel calls do_exit(0) in
675 * linux/kernel/sys.c, which can cause the machine to panic when
676 * the init process is killed.... */
677 if ((pid = fork()) == 0) {
681 waitpid (pid, NULL, 0);
684 static void shutdown_system(void)
686 sigset_t block_signals;
688 /* run everything to be run at "shutdown". This is done _prior_
689 * to killing everything, in case people wish to use scripts to
690 * shut things down gracefully... */
691 run_actions(SHUTDOWN);
693 /* first disable all our signals */
694 sigemptyset(&block_signals);
695 sigaddset(&block_signals, SIGHUP);
696 sigaddset(&block_signals, SIGCHLD);
697 sigaddset(&block_signals, SIGUSR1);
698 sigaddset(&block_signals, SIGUSR2);
699 sigaddset(&block_signals, SIGINT);
700 sigaddset(&block_signals, SIGTERM);
701 sigaddset(&block_signals, SIGCONT);
702 sigaddset(&block_signals, SIGSTOP);
703 sigaddset(&block_signals, SIGTSTP);
704 sigprocmask(SIG_BLOCK, &block_signals, NULL);
706 /* Allow Ctrl-Alt-Del to reboot system. */
707 init_reboot(RB_ENABLE_CAD);
709 message(CONSOLE | LOG, "The system is going down NOW !!");
712 /* Send signals to every process _except_ pid 1 */
713 message(CONSOLE | LOG, "Sending SIGTERM to all processes.");
718 message(CONSOLE | LOG, "Sending SIGKILL to all processes.");
725 static void exec_signal(int sig)
727 struct init_action *a, *tmp;
728 sigset_t unblock_signals;
730 for (a = init_action_list; a; a = tmp) {
732 if (a->action & RESTART) {
737 /* unblock all signals, blocked in shutdown_system() */
738 sigemptyset(&unblock_signals);
739 sigaddset(&unblock_signals, SIGHUP);
740 sigaddset(&unblock_signals, SIGCHLD);
741 sigaddset(&unblock_signals, SIGUSR1);
742 sigaddset(&unblock_signals, SIGUSR2);
743 sigaddset(&unblock_signals, SIGINT);
744 sigaddset(&unblock_signals, SIGTERM);
745 sigaddset(&unblock_signals, SIGCONT);
746 sigaddset(&unblock_signals, SIGSTOP);
747 sigaddset(&unblock_signals, SIGTSTP);
748 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
750 /* Close whatever files are open. */
755 /* Open the new terminal device */
756 if ((device_open(a->terminal, O_RDWR)) < 0) {
757 if (stat(a->terminal, &sb) != 0) {
758 message(LOG | CONSOLE, "device '%s' does not exist.", a->terminal);
760 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
762 halt_signal(SIGUSR1);
765 /* Make sure the terminal will act fairly normal for us */
767 /* Setup stdout, stderr on the supplied terminal */
771 messageD(CONSOLE | LOG, "Trying to re-exec %s", a->command);
772 execl(a->command, a->command, NULL);
774 message(CONSOLE | LOG, "exec of '%s' failed: %m",
778 init_reboot(RB_HALT_SYSTEM);
784 static void halt_signal(int sig)
787 message(CONSOLE | LOG,
789 /* Seems the s390 console is Wierd(tm). */
790 "The system is halted. You may reboot now."
792 "The system is halted. Press Reset or turn off power"
797 /* allow time for last message to reach serial console */
801 init_reboot(RB_POWER_OFF);
803 init_reboot(RB_HALT_SYSTEM);
808 static void reboot_signal(int sig)
811 message(CONSOLE | LOG, "Please stand by while rebooting the system.");
814 /* allow time for last message to reach serial console */
817 init_reboot(RB_AUTOBOOT);
822 static void ctrlaltdel_signal(int sig)
824 run_actions(CTRLALTDEL);
827 /* The SIGSTOP & SIGTSTP handler */
828 static void stop_handler(int sig)
830 int saved_errno = errno;
839 /* The SIGCONT handler */
840 static void cont_handler(int sig)
845 #endif /* ! DEBUG_INIT */
847 static void new_init_action(int action, const char *command, const char *cons)
849 struct init_action *new_action, *a;
854 /* do not run entries if console device is not available */
855 if (access(cons, R_OK | W_OK))
857 if (strcmp(cons, "/dev/null") == 0 && (action & ASKFIRST))
860 new_action = calloc((size_t) (1), sizeof(struct init_action));
862 message(LOG | CONSOLE, "Memory allocation failure");
866 /* Append to the end of the list */
867 for (a = init_action_list; a && a->next; a = a->next) {
868 /* don't enter action if it's already in the list */
869 if ((strcmp(a->command, command) == 0) &&
870 (strcmp(a->terminal, cons) ==0)) {
876 a->next = new_action;
878 init_action_list = new_action;
880 strcpy(new_action->command, command);
881 new_action->action = action;
882 strcpy(new_action->terminal, cons);
883 #if 0 /* calloc zeroed always */
886 messageD(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
887 new_action->command, new_action->action, new_action->terminal);
890 static void delete_init_action(struct init_action *action)
892 struct init_action *a, *b = NULL;
894 for (a = init_action_list; a; b = a, a = a->next) {
897 init_action_list = a->next;
907 /* Make sure there is enough memory to do something useful. *
908 * Calls "swapon -a" if needed so be sure /etc/fstab is present... */
909 static void check_memory(void)
913 if (check_free_memory() > 1000)
916 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
917 if (stat("/etc/fstab", &statBuf) == 0) {
918 /* swapon -a requires /proc typically */
919 new_init_action(SYSINIT, "/bin/mount -t proc proc /proc", "");
920 /* Try to turn on swap */
921 new_init_action(SYSINIT, "/sbin/swapon -a", "");
922 run_actions(SYSINIT); /* wait and removing */
923 if (check_free_memory() < 1000)
931 message(CONSOLE, "Sorry, your computer does not have enough memory.");
935 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
936 * then parse_inittab() simply adds in some default
937 * actions(i.e., runs INIT_SCRIPT and then starts a pair
938 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
939 * _is_ defined, but /etc/inittab is missing, this
940 * results in the same set of default behaviors.
942 static void parse_inittab(void)
944 #ifdef CONFIG_FEATURE_USE_INITTAB
946 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
947 char tmpConsole[CONSOLE_BUFF_SIZE];
948 char *id, *runlev, *action, *command, *eol;
949 const struct init_action_type *a = actions;
952 file = fopen(INITTAB, "r");
954 /* No inittab file -- set up some default behavior */
956 /* Reboot on Ctrl-Alt-Del */
957 new_init_action(CTRLALTDEL, "/sbin/reboot", "");
958 /* Umount all filesystems on halt/reboot */
959 new_init_action(SHUTDOWN, "/bin/umount -a -r", "");
960 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
961 /* Swapoff on halt/reboot */
962 new_init_action(SHUTDOWN, "/sbin/swapoff -a", "");
964 /* Prepare to restart init when a HUP is received */
965 new_init_action(RESTART, "/sbin/init", "");
966 /* Askfirst shell on tty1-4 */
967 new_init_action(ASKFIRST, bb_default_login_shell, "");
968 new_init_action(ASKFIRST, bb_default_login_shell, VC_2);
969 new_init_action(ASKFIRST, bb_default_login_shell, VC_3);
970 new_init_action(ASKFIRST, bb_default_login_shell, VC_4);
972 new_init_action(SYSINIT, INIT_SCRIPT, "");
975 #ifdef CONFIG_FEATURE_USE_INITTAB
978 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
979 /* Skip leading spaces */
980 for (id = buf; *id == ' ' || *id == '\t'; id++);
982 /* Skip the line if it's a comment */
983 if (*id == '#' || *id == '\n')
986 /* Trim the trailing \n */
987 eol = strrchr(id, '\n');
991 /* Keep a copy around for posterity's sake (and error msgs) */
992 strcpy(lineAsRead, buf);
994 /* Separate the ID field from the runlevels */
995 runlev = strchr(id, ':');
996 if (runlev == NULL || *(runlev + 1) == '\0') {
997 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1004 /* Separate the runlevels from the action */
1005 action = strchr(runlev, ':');
1006 if (action == NULL || *(action + 1) == '\0') {
1007 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1014 /* Separate the action from the command */
1015 command = strchr(action, ':');
1016 if (command == NULL || *(command + 1) == '\0') {
1017 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1024 /* Ok, now process it */
1025 for (a = actions; a->name != 0; a++) {
1026 if (strcmp(a->name, action) == 0) {
1028 if(strncmp(id, "/dev/", 5) == 0)
1030 strcpy(tmpConsole, "/dev/");
1031 safe_strncpy(tmpConsole + 5, id,
1032 CONSOLE_BUFF_SIZE - 5);
1035 new_init_action(a->action, command, id);
1040 /* Choke on an unknown action */
1041 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1046 #endif /* CONFIG_FEATURE_USE_INITTAB */
1049 static void reload_signal(int sig)
1051 message(LOG, "Reloading /etc/inittab");
1053 run_actions(RESPAWN);
1057 extern int init_main(int argc, char **argv)
1059 struct init_action *a;
1063 if (argc > 1 && !strcmp(argv[1], "-q")) {
1064 return kill_init(SIGHUP);
1067 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1069 #ifdef CONFIG_FEATURE_INITRD
1070 && strstr(bb_applet_name, "linuxrc") == NULL
1075 /* Set up sig handlers -- be sure to
1076 * clear all of these in run() */
1077 signal(SIGHUP, exec_signal);
1078 signal(SIGUSR1, halt_signal);
1079 signal(SIGUSR2, halt_signal);
1080 signal(SIGINT, ctrlaltdel_signal);
1081 signal(SIGTERM, reboot_signal);
1082 signal(SIGCONT, cont_handler);
1083 signal(SIGSTOP, stop_handler);
1084 signal(SIGTSTP, stop_handler);
1086 /* Turn off rebooting via CTL-ALT-DEL -- we get a
1087 * SIGINT on CAD so we can shut things down gracefully... */
1088 init_reboot(RB_DISABLE_CAD);
1091 /* Figure out where the default console should be */
1094 /* Close whatever files are open, and reset the console. */
1099 if (device_open(console, O_RDWR | O_NOCTTY) == 0) {
1107 const char * const *e;
1108 /* Make sure environs is set to something sane */
1109 for(e = environment; *e; e++)
1110 putenv((char *) *e);
1113 message(MAYBE_CONSOLE | LOG, "init started: %s", bb_msg_full_version);
1115 /* Make sure there is enough memory to do something useful. */
1118 /* Check if we are supposed to be in single user mode */
1119 if (argc > 1 && (!strcmp(argv[1], "single") ||
1120 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1121 /* Start a shell on console */
1122 new_init_action(RESPAWN, bb_default_login_shell, "");
1124 /* Not in single user mode -- see what inittab says */
1126 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1127 * then parse_inittab() simply adds in some default
1128 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1129 * of "askfirst" shells */
1133 /* Make the command line just say "init" -- thats all, nothing else */
1134 fixup_argv(argc, argv, "init");
1136 /* Now run everything that needs to be run */
1138 /* First run the sysinit command */
1139 run_actions(SYSINIT);
1141 /* Next run anything that wants to block */
1144 /* Next run anything to be run only once */
1147 /* If there is nothing else to do, stop */
1148 if (init_action_list == NULL) {
1149 message(LOG | CONSOLE,
1150 "No more tasks for init -- sleeping forever.");
1154 /* Redefine SIGHUP to reread /etc/inittab */
1155 signal(SIGHUP, reload_signal);
1157 /* Now run the looping stuff for the rest of forever */
1159 /* run the respawn stuff */
1160 run_actions(RESPAWN);
1162 /* run the askfirst stuff */
1163 run_actions(ASKFIRST);
1165 /* Don't consume all CPU time -- sleep a bit */
1168 /* Wait for a child process to exit */
1169 wpid = wait(&status);
1171 /* Find out who died and clean up their corpse */
1172 for (a = init_action_list; a; a = a->next) {
1173 if (a->pid == wpid) {
1174 /* Set the pid to 0 so that the process gets
1175 * restarted by run_actions() */
1177 message(LOG, "Process '%s' (pid %d) exited. "
1178 "Scheduling it for restart.",
1182 /* see if anyone else is waiting to be reaped */
1183 wpid = waitpid (-1, &status, WNOHANG);
1190 c-file-style: "linux"