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.
12 /* Turn this on to disable all the dangerous
13 rebooting stuff when debugging.
27 #include <sys/fcntl.h>
28 #include <sys/ioctl.h>
29 #include <sys/types.h>
31 #include <sys/reboot.h>
34 #include "init_shared.h"
38 # include <sys/syslog.h>
42 #define INIT_BUFFS_SIZE 256
44 /* From <linux/vt.h> */
46 unsigned short v_active; /* active vt */
47 unsigned short v_signal; /* signal to send */
48 unsigned short v_state; /* vt bitmask */
50 static const int VT_GETSTATE = 0x5603; /* get global vt state info */
52 /* From <linux/serial.h> */
53 struct serial_struct {
62 unsigned short close_delay;
64 char reserved_char[1];
66 unsigned short closing_wait; /* time to wait before closing */
67 unsigned short closing_wait2; /* no longer used... */
68 unsigned char *iomem_base;
69 unsigned short iomem_reg_shift;
70 unsigned int port_high;
71 unsigned long iomap_base; /* cookie passed into ioremap */
77 #define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
80 #if defined CONFIG_FEATURE_INIT_COREDUMPS
82 * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
83 * before processes are spawned to set core file size as unlimited.
84 * This is for debugging only. Don't use this is production, unless
85 * you want core dumps lying about....
87 #define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
88 #include <sys/resource.h>
92 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
94 #define INITTAB "/etc/inittab" /* inittab file location */
96 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
99 #define MAXENV 16 /* Number of env. vars */
101 #define CONSOLE_BUFF_SIZE 32
103 /* Allowed init action types */
104 #define SYSINIT 0x001
105 #define RESPAWN 0x002
106 #define ASKFIRST 0x004
109 #define CTRLALTDEL 0x020
110 #define SHUTDOWN 0x040
111 #define RESTART 0x080
113 /* A mapping between "inittab" action name strings and action type codes. */
114 struct init_action_type {
119 static const struct init_action_type actions[] = {
120 {"sysinit", SYSINIT},
121 {"respawn", RESPAWN},
122 {"askfirst", ASKFIRST},
125 {"ctrlaltdel", CTRLALTDEL},
126 {"shutdown", SHUTDOWN},
127 {"restart", RESTART},
131 /* Set up a linked list of init_actions, to be read from inittab */
134 char command[INIT_BUFFS_SIZE];
135 char terminal[CONSOLE_BUFF_SIZE];
136 struct init_action *next;
140 /* Static variables */
141 static struct init_action *init_action_list = NULL;
142 static char console[CONSOLE_BUFF_SIZE] = _PATH_CONSOLE;
144 #ifndef CONFIG_SYSLOGD
145 static char *log_console = VC_5;
147 static sig_atomic_t got_cont = 0;
148 static const int LOG = 0x1;
149 static const int CONSOLE = 0x2;
151 #if defined CONFIG_FEATURE_EXTRA_QUIET
152 static const int MAYBE_CONSOLE = 0x0;
154 #define MAYBE_CONSOLE CONSOLE
156 #ifndef RB_HALT_SYSTEM
157 static const int RB_HALT_SYSTEM = 0xcdef0123;
158 static const int RB_ENABLE_CAD = 0x89abcdef;
159 static const int RB_DISABLE_CAD = 0;
161 #define RB_POWER_OFF 0x4321fedc
162 static const int RB_AUTOBOOT = 0x01234567;
165 static const char * const environment[] = {
167 "PATH=" _PATH_STDPATH,
173 /* Function prototypes */
174 static void delete_init_action(struct init_action *a);
175 static int waitfor(const struct init_action *a);
176 static void halt_signal(int sig);
179 static void loop_forever(void)
185 /* Print a message to the specified device.
186 * Device may be bitwise-or'd from LOG | CONSOLE */
188 static inline void messageD(int device, const char *fmt, ...)
192 #define messageD message
194 static void message(int device, const char *fmt, ...)
195 __attribute__ ((format(printf, 2, 3)));
196 static void message(int device, const char *fmt, ...)
201 #ifndef CONFIG_SYSLOGD
202 static int log_fd = -1;
206 va_start(arguments, fmt);
207 l = vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments) + 1;
210 #ifdef CONFIG_SYSLOGD
211 /* Log the message to syslogd */
213 /* don`t out "\r\n" */
214 openlog(bb_applet_name, 0, LOG_DAEMON);
215 syslog(LOG_INFO, "%s", msg + 1);
225 /* Take full control of the log tty, and never close it.
226 * It's mine, all mine! Muhahahaha! */
228 if ((log_fd = device_open(log_console, O_RDWR | O_NONBLOCK | O_NOCTTY)) < 0) {
230 bb_error_msg("Bummer, can't write to log on %s!", log_console);
233 fcntl(log_fd, F_SETFD, FD_CLOEXEC);
236 if ((device & LOG) && (log_fd >= 0)) {
237 bb_full_write(log_fd, msg, l);
241 if (device & CONSOLE) {
242 int fd = device_open(_PATH_CONSOLE,
243 O_WRONLY | O_NOCTTY | O_NONBLOCK);
244 /* Always send console messages to /dev/console so people will see them. */
246 bb_full_write(fd, msg, l);
249 /* all descriptors may be closed */
251 bb_error_msg("Bummer, can't print: ");
252 va_start(arguments, fmt);
253 vfprintf(stderr, fmt, arguments);
260 /* Set terminal settings to reasonable defaults */
261 static void set_term(int fd)
267 /* set control chars */
268 tty.c_cc[VINTR] = 3; /* C-c */
269 tty.c_cc[VQUIT] = 28; /* C-\ */
270 tty.c_cc[VERASE] = 127; /* C-? */
271 tty.c_cc[VKILL] = 21; /* C-u */
272 tty.c_cc[VEOF] = 4; /* C-d */
273 tty.c_cc[VSTART] = 17; /* C-q */
274 tty.c_cc[VSTOP] = 19; /* C-s */
275 tty.c_cc[VSUSP] = 26; /* C-z */
277 /* use line dicipline 0 */
280 /* Make it be sane */
281 tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
282 tty.c_cflag |= CREAD | HUPCL | CLOCAL;
286 tty.c_iflag = ICRNL | IXON | IXOFF;
289 tty.c_oflag = OPOST | ONLCR;
293 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
295 tcsetattr(fd, TCSANOW, &tty);
298 static void console_init(void)
303 struct serial_struct sr;
306 if ((s = getenv("CONSOLE")) != NULL || (s = getenv("console")) != NULL) {
307 safe_strncpy(console, s, sizeof(console));
309 /* sparc kernel supports console=tty[ab] parameter which is also
310 * passed to init, so catch it here */
311 /* remap tty[ab] to /dev/ttyS[01] */
312 if (strcmp(s, "ttya") == 0)
313 safe_strncpy(console, SC_0, sizeof(console));
314 else if (strcmp(s, "ttyb") == 0)
315 safe_strncpy(console, SC_1, sizeof(console));
318 /* 2.2 kernels: identify the real console backend and try to use it */
319 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
320 /* this is a serial console */
321 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
322 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
323 /* this is linux virtual tty */
324 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
326 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
331 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0 && tried < 2) {
332 /* Can't open selected console -- try
333 logical system console and VT_MASTER */
334 safe_strncpy(console, (tried == 0 ? _PATH_CONSOLE : CURRENT_VC),
339 /* Perhaps we should panic here? */
340 #ifndef CONFIG_SYSLOGD
343 safe_strncpy(console, bb_dev_null, sizeof(console));
346 /* check for serial console */
347 if (ioctl(fd, TIOCGSERIAL, &sr) == 0) {
348 /* Force the TERM setting to vt102 for serial console --
349 * if TERM is set to linux (the default) */
350 if (s == NULL || strcmp(s, "linux") == 0)
351 putenv("TERM=vt102");
352 #ifndef CONFIG_SYSLOGD
353 log_console = console;
357 putenv("TERM=linux");
361 messageD(LOG, "console=%s", console);
364 static void fixup_argv(int argc, char **argv, char *new_argv0)
368 /* Fix up argv[0] to be certain we claim to be init */
369 len = strlen(argv[0]);
370 memset(argv[0], 0, len);
371 safe_strncpy(argv[0], new_argv0, len + 1);
373 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
376 memset(argv[len], 0, strlen(argv[len]));
381 static pid_t run(const struct init_action *a)
385 char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
386 char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
387 sigset_t nmask, omask;
388 static const char press_enter[] =
389 #ifdef CUSTOMIZED_BANNER
390 #include CUSTOMIZED_BANNER
392 "\nPlease press Enter to activate this console. ";
394 /* Block sigchild while forking. */
396 sigaddset(&nmask, SIGCHLD);
397 sigprocmask(SIG_BLOCK, &nmask, &omask);
399 if ((pid = fork()) == 0) {
406 sigprocmask(SIG_SETMASK, &omask, NULL);
408 /* Reset signal handlers that were set by the parent process */
409 signal(SIGUSR1, SIG_DFL);
410 signal(SIGUSR2, SIG_DFL);
411 signal(SIGINT, SIG_DFL);
412 signal(SIGTERM, SIG_DFL);
413 signal(SIGHUP, SIG_DFL);
414 signal(SIGQUIT, SIG_DFL);
415 signal(SIGCONT, SIG_DFL);
416 signal(SIGSTOP, SIG_DFL);
417 signal(SIGTSTP, SIG_DFL);
419 /* Create a new session and make ourself the process
423 /* Open the new terminal device */
424 if ((device_open(a->terminal, O_RDWR)) < 0) {
425 if (stat(a->terminal, &sb) != 0) {
426 message(LOG | CONSOLE, "device '%s' does not exist.", a->terminal);
428 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
433 /* Make sure the terminal will act fairly normal for us */
435 /* Setup stdout, stderr for the new process so
436 * they point to the supplied terminal */
440 /* If the init Action requires us to wait, then force the
441 * supplied terminal to be the controlling tty. */
442 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
445 /* Now fork off another process to just hang around */
446 if ((pid = fork()) < 0) {
447 message(LOG | CONSOLE, "Can't fork!");
453 /* We are the parent -- wait till the child is done */
454 signal(SIGINT, SIG_IGN);
455 signal(SIGTSTP, SIG_IGN);
456 signal(SIGQUIT, SIG_IGN);
457 signal(SIGCHLD, SIG_DFL);
459 /* Wait for child to exit */
460 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
461 if (tmp_pid == -1 && errno == ECHILD) {
464 /* FIXME handle other errors */
467 /* See if stealing the controlling tty back is necessary */
469 if (pgrp != getpid())
472 /* Use a temporary process to steal the controlling tty. */
473 if ((pid = fork()) < 0) {
474 message(LOG | CONSOLE, "Can't fork!");
479 ioctl(0, TIOCSCTTY, 1);
482 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
483 if (tmp_pid < 0 && errno == ECHILD)
489 /* Now fall though to actually execute things */
492 /* See if any special /bin/sh requiring characters are present */
493 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
494 cmd[0] = (char *)DEFAULT_SHELL;
496 cmd[2] = strcat(strcpy(buf, "exec "), a->command);
499 /* Convert command (char*) into cmd (char**, one word per string) */
500 strcpy(buf, a->command);
502 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
503 if (*tmpCmd != '\0') {
514 Interactive shells want to see a dash in argv[0]. This
515 typically is handled by login, argv will be setup this
516 way if a dash appears at the front of the command path
520 if (*cmdpath == '-') {
522 /* skip over the dash */
525 /* find the last component in the command pathname */
526 s = bb_get_last_path_component(cmdpath);
528 /* make a new argv[0] */
529 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
530 message(LOG | CONSOLE, bb_msg_memory_exhausted);
534 strcpy(cmd[0] + 1, s);
536 #ifdef CONFIG_FEATURE_INIT_SCTTY
537 /* Establish this process as session leader and
538 * (attempt) to make the tty (if any) a controlling tty.
541 (void) ioctl(0, TIOCSCTTY, 0/*don't steal it*/);
545 #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
546 if (a->action & ASKFIRST) {
549 * Save memory by not exec-ing anything large (like a shell)
550 * before the user wants it. This is critical if swap is not
551 * enabled and the system has low memory. Generally this will
552 * be run on the second virtual console, and the first will
553 * be allowed to start a shell or whatever an init script
556 messageD(LOG, "Waiting for enter to start '%s'"
557 "(pid %d, terminal %s)\n",
558 cmdpath, getpid(), a->terminal);
559 bb_full_write(1, press_enter, sizeof(press_enter) - 1);
560 while(read(0, &c, 1) == 1 && c != '\n')
565 /* Log the process name and args */
566 message(LOG, "Starting pid %d, console %s: '%s'",
567 getpid(), a->terminal, cmdpath);
569 #if defined CONFIG_FEATURE_INIT_COREDUMPS
570 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
573 limit.rlim_cur = RLIM_INFINITY;
574 limit.rlim_max = RLIM_INFINITY;
575 setrlimit(RLIMIT_CORE, &limit);
579 /* Now run it. The new program will take over this PID,
580 * so nothing further in init.c should be run. */
583 /* We're still here? Some error happened. */
584 message(LOG | CONSOLE, "Bummer, could not run '%s': %m", cmdpath);
587 sigprocmask(SIG_SETMASK, &omask, NULL);
591 static int waitfor(const struct init_action *a)
598 wpid = waitpid(pid,&status,0);
601 if (wpid == -1 && errno == ECHILD) {
602 /* we missed its termination */
605 /* FIXME other errors should maybe trigger an error, but allow
606 * the program to continue */
611 /* Run all commands of a particular type */
612 static void run_actions(int action)
614 struct init_action *a, *tmp;
616 for (a = init_action_list; a; a = tmp) {
618 if (a->action == action) {
619 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
621 delete_init_action(a);
622 } else if (a->action & ONCE) {
624 delete_init_action(a);
625 } else if (a->action & (RESPAWN | ASKFIRST)) {
626 /* Only run stuff with pid==0. If they have
627 * a pid, that means it is still running */
637 static void init_reboot(unsigned long magic)
640 /* We have to fork here, since the kernel calls do_exit(0) in
641 * linux/kernel/sys.c, which can cause the machine to panic when
642 * the init process is killed.... */
643 if ((pid = fork()) == 0) {
647 waitpid (pid, NULL, 0);
650 static void shutdown_system(void)
652 sigset_t block_signals;
654 /* run everything to be run at "shutdown". This is done _prior_
655 * to killing everything, in case people wish to use scripts to
656 * shut things down gracefully... */
657 run_actions(SHUTDOWN);
659 /* first disable all our signals */
660 sigemptyset(&block_signals);
661 sigaddset(&block_signals, SIGHUP);
662 sigaddset(&block_signals, SIGQUIT);
663 sigaddset(&block_signals, SIGCHLD);
664 sigaddset(&block_signals, SIGUSR1);
665 sigaddset(&block_signals, SIGUSR2);
666 sigaddset(&block_signals, SIGINT);
667 sigaddset(&block_signals, SIGTERM);
668 sigaddset(&block_signals, SIGCONT);
669 sigaddset(&block_signals, SIGSTOP);
670 sigaddset(&block_signals, SIGTSTP);
671 sigprocmask(SIG_BLOCK, &block_signals, NULL);
673 /* Allow Ctrl-Alt-Del to reboot system. */
674 init_reboot(RB_ENABLE_CAD);
676 message(CONSOLE | LOG, "The system is going down NOW !!");
679 /* Send signals to every process _except_ pid 1 */
680 message(CONSOLE | LOG, "Sending SIGTERM to all processes.");
685 message(CONSOLE | LOG, "Sending SIGKILL to all processes.");
692 static void exec_signal(int sig)
694 struct init_action *a, *tmp;
695 sigset_t unblock_signals;
697 for (a = init_action_list; a; a = tmp) {
699 if (a->action & RESTART) {
702 /* unblock all signals, blocked in shutdown_system() */
703 sigemptyset(&unblock_signals);
704 sigaddset(&unblock_signals, SIGHUP);
705 sigaddset(&unblock_signals, SIGQUIT);
706 sigaddset(&unblock_signals, SIGCHLD);
707 sigaddset(&unblock_signals, SIGUSR1);
708 sigaddset(&unblock_signals, SIGUSR2);
709 sigaddset(&unblock_signals, SIGINT);
710 sigaddset(&unblock_signals, SIGTERM);
711 sigaddset(&unblock_signals, SIGCONT);
712 sigaddset(&unblock_signals, SIGSTOP);
713 sigaddset(&unblock_signals, SIGTSTP);
714 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
716 /* Close whatever files are open. */
721 /* Open the new terminal device */
722 if ((device_open(a->terminal, O_RDWR)) < 0) {
724 if (stat(a->terminal, &sb) != 0) {
725 message(LOG | CONSOLE, "device '%s' does not exist.", a->terminal);
727 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
729 halt_signal(SIGUSR1);
732 /* Make sure the terminal will act fairly normal for us */
734 /* Setup stdout, stderr on the supplied terminal */
738 messageD(CONSOLE | LOG, "Trying to re-exec %s", a->command);
739 execl(a->command, a->command, NULL);
741 message(CONSOLE | LOG, "exec of '%s' failed: %m",
745 init_reboot(RB_HALT_SYSTEM);
751 static void halt_signal(int sig)
754 message(CONSOLE | LOG,
756 /* Seems the s390 console is Wierd(tm). */
757 "The system is halted. You may reboot now."
759 "The system is halted. Press Reset or turn off power"
764 /* allow time for last message to reach serial console */
768 init_reboot(RB_POWER_OFF);
770 init_reboot(RB_HALT_SYSTEM);
775 static void reboot_signal(int sig)
778 message(CONSOLE | LOG, "Please stand by while rebooting the system.");
781 /* allow time for last message to reach serial console */
784 init_reboot(RB_AUTOBOOT);
789 static void ctrlaltdel_signal(int sig)
791 run_actions(CTRLALTDEL);
794 /* The SIGSTOP & SIGTSTP handler */
795 static void stop_handler(int sig)
797 int saved_errno = errno;
806 /* The SIGCONT handler */
807 static void cont_handler(int sig)
812 #endif /* ! DEBUG_INIT */
814 static void new_init_action(int action, const char *command, const char *cons)
816 struct init_action *new_action, *a, *last;
821 /* do not run entries if console device is not available */
822 if (access(cons, R_OK | W_OK))
824 if (strcmp(cons, bb_dev_null) == 0 && (action & ASKFIRST))
827 new_action = calloc((size_t) (1), sizeof(struct init_action));
829 message(LOG | CONSOLE, "Memory allocation failure");
833 /* Append to the end of the list */
834 for (a = last = init_action_list; a; a = a->next) {
835 /* don't enter action if it's already in the list,
836 * but do overwrite existing actions */
837 if ((strcmp(a->command, command) == 0) &&
838 (strcmp(a->terminal, cons) ==0)) {
846 last->next = new_action;
848 init_action_list = new_action;
850 strcpy(new_action->command, command);
851 new_action->action = action;
852 strcpy(new_action->terminal, cons);
853 #if 0 /* calloc zeroed always */
856 messageD(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
857 new_action->command, new_action->action, new_action->terminal);
860 static void delete_init_action(struct init_action *action)
862 struct init_action *a, *b = NULL;
864 for (a = init_action_list; a; b = a, a = a->next) {
867 init_action_list = a->next;
877 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
878 * then parse_inittab() simply adds in some default
879 * actions(i.e., runs INIT_SCRIPT and then starts a pair
880 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
881 * _is_ defined, but /etc/inittab is missing, this
882 * results in the same set of default behaviors.
884 static void parse_inittab(void)
886 #ifdef CONFIG_FEATURE_USE_INITTAB
888 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
889 char tmpConsole[CONSOLE_BUFF_SIZE];
890 char *id, *runlev, *action, *command, *eol;
891 const struct init_action_type *a = actions;
894 file = fopen(INITTAB, "r");
896 /* No inittab file -- set up some default behavior */
898 /* Reboot on Ctrl-Alt-Del */
899 new_init_action(CTRLALTDEL, "/sbin/reboot", "");
900 /* Umount all filesystems on halt/reboot */
901 new_init_action(SHUTDOWN, "/bin/umount -a -r", "");
902 /* Swapoff on halt/reboot */
903 if(ENABLE_SWAPONOFF) new_init_action(SHUTDOWN, "/sbin/swapoff -a", "");
904 /* Prepare to restart init when a HUP is received */
905 new_init_action(RESTART, "/sbin/init", "");
906 /* Askfirst shell on tty1-4 */
907 new_init_action(ASKFIRST, bb_default_login_shell, "");
908 new_init_action(ASKFIRST, bb_default_login_shell, VC_2);
909 new_init_action(ASKFIRST, bb_default_login_shell, VC_3);
910 new_init_action(ASKFIRST, bb_default_login_shell, VC_4);
912 new_init_action(SYSINIT, INIT_SCRIPT, "");
915 #ifdef CONFIG_FEATURE_USE_INITTAB
918 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
919 /* Skip leading spaces */
920 for (id = buf; *id == ' ' || *id == '\t'; id++);
922 /* Skip the line if it's a comment */
923 if (*id == '#' || *id == '\n')
926 /* Trim the trailing \n */
927 eol = strrchr(id, '\n');
931 /* Keep a copy around for posterity's sake (and error msgs) */
932 strcpy(lineAsRead, buf);
934 /* Separate the ID field from the runlevels */
935 runlev = strchr(id, ':');
936 if (runlev == NULL || *(runlev + 1) == '\0') {
937 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
944 /* Separate the runlevels from the action */
945 action = strchr(runlev, ':');
946 if (action == NULL || *(action + 1) == '\0') {
947 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
954 /* Separate the action from the command */
955 command = strchr(action, ':');
956 if (command == NULL || *(command + 1) == '\0') {
957 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
964 /* Ok, now process it */
965 for (a = actions; a->name != 0; a++) {
966 if (strcmp(a->name, action) == 0) {
968 if(strncmp(id, "/dev/", 5) == 0)
970 strcpy(tmpConsole, "/dev/");
971 safe_strncpy(tmpConsole + 5, id,
972 CONSOLE_BUFF_SIZE - 5);
975 new_init_action(a->action, command, id);
980 /* Choke on an unknown action */
981 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
986 #endif /* CONFIG_FEATURE_USE_INITTAB */
989 #ifdef CONFIG_FEATURE_USE_INITTAB
990 static void reload_signal(int sig)
992 struct init_action *a, *tmp;
994 message(LOG, "Reloading /etc/inittab");
996 /* disable old entrys */
997 for (a = init_action_list; a; a = a->next ) {
1003 /* remove unused entrys */
1004 for (a = init_action_list; a; a = tmp) {
1006 if (a->action & (ONCE | SYSINIT | WAIT ) &&
1008 delete_init_action(a);
1011 run_actions(RESPAWN);
1014 #endif /* CONFIG_FEATURE_USE_INITTAB */
1016 extern int init_main(int argc, char **argv)
1018 struct init_action *a;
1022 if (argc > 1 && !strcmp(argv[1], "-q")) {
1023 return kill(1,SIGHUP);
1026 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1028 #ifdef CONFIG_FEATURE_INITRD
1029 && strstr(bb_applet_name, "linuxrc") == NULL
1034 /* Set up sig handlers -- be sure to
1035 * clear all of these in run() */
1036 signal(SIGHUP, exec_signal);
1037 signal(SIGQUIT, exec_signal);
1038 signal(SIGUSR1, halt_signal);
1039 signal(SIGUSR2, halt_signal);
1040 signal(SIGINT, ctrlaltdel_signal);
1041 signal(SIGTERM, reboot_signal);
1042 signal(SIGCONT, cont_handler);
1043 signal(SIGSTOP, stop_handler);
1044 signal(SIGTSTP, stop_handler);
1046 /* Turn off rebooting via CTL-ALT-DEL -- we get a
1047 * SIGINT on CAD so we can shut things down gracefully... */
1048 init_reboot(RB_DISABLE_CAD);
1051 /* Figure out where the default console should be */
1054 /* Close whatever files are open, and reset the console. */
1059 if (device_open(console, O_RDWR | O_NOCTTY) == 0) {
1067 const char * const *e;
1068 /* Make sure environs is set to something sane */
1069 for(e = environment; *e; e++)
1070 putenv((char *) *e);
1073 message(MAYBE_CONSOLE | LOG, "init started: %s", bb_msg_full_version);
1075 /* Make sure there is enough memory to do something useful. */
1076 if (ENABLE_SWAPONOFF) {
1077 struct sysinfo info;
1079 if (!sysinfo(&info) &&
1080 (info.mem_unit ? : 1) * (long long)info.totalram < MEGABYTE)
1082 message(CONSOLE,"Low memory: forcing swapon.");
1083 /* swapon -a requires /proc typically */
1084 new_init_action(SYSINIT, "/bin/mount -t proc proc /proc", "");
1085 /* Try to turn on swap */
1086 new_init_action(SYSINIT, "/sbin/swapon -a", "");
1087 run_actions(SYSINIT); /* wait and removing */
1091 /* Check if we are supposed to be in single user mode */
1092 if (argc > 1 && (!strcmp(argv[1], "single") ||
1093 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1094 /* Start a shell on console */
1095 new_init_action(RESPAWN, bb_default_login_shell, "");
1097 /* Not in single user mode -- see what inittab says */
1099 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1100 * then parse_inittab() simply adds in some default
1101 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1102 * of "askfirst" shells */
1106 /* Make the command line just say "init" -- thats all, nothing else */
1107 fixup_argv(argc, argv, "init");
1109 /* Now run everything that needs to be run */
1111 /* First run the sysinit command */
1112 run_actions(SYSINIT);
1114 /* Next run anything that wants to block */
1117 /* Next run anything to be run only once */
1120 #ifdef CONFIG_FEATURE_USE_INITTAB
1121 /* Redefine SIGHUP to reread /etc/inittab */
1122 signal(SIGHUP, reload_signal);
1124 signal(SIGHUP, SIG_IGN);
1125 #endif /* CONFIG_FEATURE_USE_INITTAB */
1128 /* Now run the looping stuff for the rest of forever */
1130 /* run the respawn stuff */
1131 run_actions(RESPAWN);
1133 /* run the askfirst stuff */
1134 run_actions(ASKFIRST);
1136 /* Don't consume all CPU time -- sleep a bit */
1139 /* Wait for a child process to exit */
1140 wpid = wait(&status);
1142 /* Find out who died and clean up their corpse */
1143 for (a = init_action_list; a; a = a->next) {
1144 if (a->pid == wpid) {
1145 /* Set the pid to 0 so that the process gets
1146 * restarted by run_actions() */
1148 message(LOG, "Process '%s' (pid %d) exited. "
1149 "Scheduling it for restart.",
1153 /* see if anyone else is waiting to be reaped */
1154 wpid = waitpid (-1, &status, WNOHANG);
1161 c-file-style: "linux"