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 "init_shared.h"
51 # include <sys/syslog.h>
53 #if (__GNU_LIBRARY__ > 5) || defined(__dietlibc__)
54 #include <sys/reboot.h>
58 #if defined(__UCLIBC__) && !defined(__UCLIBC_HAS_MMU__)
62 #define INIT_BUFFS_SIZE 256
64 /* From <linux/vt.h> */
66 unsigned short v_active; /* active vt */
67 unsigned short v_signal; /* signal to send */
68 unsigned short v_state; /* vt bitmask */
70 static const int VT_GETSTATE = 0x5603; /* get global vt state info */
72 /* From <linux/serial.h> */
73 struct serial_struct {
82 unsigned short close_delay;
83 char reserved_char[2];
85 unsigned short closing_wait; /* time to wait before closing */
86 unsigned short closing_wait2; /* no longer used... */
92 #define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
95 #if defined CONFIG_FEATURE_INIT_COREDUMPS
97 * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
98 * before processes are spawned to set core file size as unlimited.
99 * This is for debugging only. Don't use this is production, unless
100 * you want core dumps lying about....
102 #define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
103 #include <sys/resource.h>
104 #include <sys/time.h>
107 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
109 #define SHELL "/bin/sh" /* Default shell */
110 #define LOGIN_SHELL "-" SHELL /* Default login shell */
111 #define INITTAB "/etc/inittab" /* inittab file location */
113 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
116 #define MAXENV 16 /* Number of env. vars */
118 #define CONSOLE_BUFF_SIZE 32
120 /* Allowed init action types */
121 #define SYSINIT 0x001
122 #define RESPAWN 0x002
123 #define ASKFIRST 0x004
126 #define CTRLALTDEL 0x020
127 #define SHUTDOWN 0x040
128 #define RESTART 0x080
130 /* A mapping between "inittab" action name strings and action type codes. */
131 struct init_action_type {
136 static const struct init_action_type actions[] = {
137 {"sysinit", SYSINIT},
138 {"respawn", RESPAWN},
139 {"askfirst", ASKFIRST},
142 {"ctrlaltdel", CTRLALTDEL},
143 {"shutdown", SHUTDOWN},
144 {"restart", RESTART},
148 /* Set up a linked list of init_actions, to be read from inittab */
151 char command[INIT_BUFFS_SIZE];
152 char terminal[CONSOLE_BUFF_SIZE];
153 struct init_action *next;
157 /* Static variables */
158 static struct init_action *init_action_list = NULL;
159 static char console[CONSOLE_BUFF_SIZE] = _PATH_CONSOLE;
161 #ifndef CONFIG_SYSLOGD
162 static char *log = VC_5;
164 static sig_atomic_t got_cont = 0;
165 static const int LOG = 0x1;
166 static const int CONSOLE = 0x2;
168 #if defined CONFIG_FEATURE_EXTRA_QUIET
169 static const int MAYBE_CONSOLE = 0x0;
171 #define MAYBE_CONSOLE CONSOLE
173 #ifndef RB_HALT_SYSTEM
174 static const int RB_HALT_SYSTEM = 0xcdef0123;
175 static const int RB_ENABLE_CAD = 0x89abcdef;
176 static const int RB_DISABLE_CAD = 0;
178 #define RB_POWER_OFF 0x4321fedc
179 static const int RB_AUTOBOOT = 0x01234567;
182 static const char * const environment[] = {
184 "PATH=" _PATH_STDPATH,
190 /* Function prototypes */
191 static void delete_init_action(struct init_action *a);
192 static int waitfor(const struct init_action *a);
195 static void loop_forever(void)
201 /* Print a message to the specified device.
202 * Device may be bitwise-or'd from LOG | CONSOLE */
204 static inline void messageD(int device, const char *fmt, ...)
208 #define messageD message
210 static void message(int device, const char *fmt, ...)
211 __attribute__ ((format(printf, 2, 3)));
212 static void message(int device, const char *fmt, ...)
217 #ifndef CONFIG_SYSLOGD
218 static int log_fd = -1;
222 va_start(arguments, fmt);
223 l = vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments) + 1;
226 #ifdef CONFIG_SYSLOGD
227 /* Log the message to syslogd */
229 /* don`t out "\r\n" */
230 syslog_msg(LOG_DAEMON, LOG_INFO, msg + 1);
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 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);
340 static void console_init(void)
345 struct serial_struct sr;
348 if ((s = getenv("CONSOLE")) != NULL || (s = getenv("console")) != NULL) {
349 safe_strncpy(console, s, sizeof(console));
351 /* sparc kernel supports console=tty[ab] parameter which is also
352 * passed to init, so catch it here */
353 /* remap tty[ab] to /dev/ttyS[01] */
354 if (strcmp(s, "ttya") == 0)
355 safe_strncpy(console, SC_0, sizeof(console));
356 else if (strcmp(s, "ttyb") == 0)
357 safe_strncpy(console, SC_1, sizeof(console));
360 /* 2.2 kernels: identify the real console backend and try to use it */
361 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
362 /* this is a serial console */
363 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
364 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
365 /* this is linux virtual tty */
366 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
368 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
373 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0 && tried < 2) {
374 /* Can't open selected console -- try
375 logical system console and VT_MASTER */
376 safe_strncpy(console, (tried == 0 ? _PATH_CONSOLE : CURRENT_VC),
381 /* Perhaps we should panic here? */
382 #ifndef CONFIG_SYSLOGD
385 safe_strncpy(console, "/dev/null", sizeof(console));
388 /* check for serial console */
389 if (ioctl(fd, TIOCGSERIAL, &sr) == 0) {
390 /* Force the TERM setting to vt102 for serial console --
391 * if TERM is set to linux (the default) */
392 if (s == NULL || strcmp(s, "linux") == 0)
393 putenv("TERM=vt102");
394 #ifndef CONFIG_SYSLOGD
399 putenv("TERM=linux");
403 messageD(LOG, "console=%s", console);
406 static void fixup_argv(int argc, char **argv, char *new_argv0)
410 /* Fix up argv[0] to be certain we claim to be init */
411 len = strlen(argv[0]);
412 memset(argv[0], 0, len);
413 safe_strncpy(argv[0], new_argv0, len + 1);
415 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
418 memset(argv[len], 0, strlen(argv[len]));
423 static pid_t run(const struct init_action *a)
427 pid_t pid, pgrp, tmp_pid;
428 char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
429 char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
430 sigset_t nmask, omask;
431 static const char press_enter[] =
432 #ifdef CUSTOMIZED_BANNER
433 #include CUSTOMIZED_BANNER
435 "\nPlease press Enter to activate this console. ";
437 /* Block sigchild while forking. */
439 sigaddset(&nmask, SIGCHLD);
440 sigprocmask(SIG_BLOCK, &nmask, &omask);
442 if ((pid = fork()) == 0) {
447 sigprocmask(SIG_SETMASK, &omask, NULL);
449 /* Reset signal handlers that were set by the parent process */
450 signal(SIGUSR1, SIG_DFL);
451 signal(SIGUSR2, SIG_DFL);
452 signal(SIGINT, SIG_DFL);
453 signal(SIGTERM, SIG_DFL);
454 signal(SIGHUP, SIG_DFL);
455 signal(SIGCONT, SIG_DFL);
456 signal(SIGSTOP, SIG_DFL);
457 signal(SIGTSTP, SIG_DFL);
459 /* Create a new session and make ourself the process
463 /* Open the new terminal device */
464 if ((device_open(a->terminal, O_RDWR)) < 0) {
465 if (stat(a->terminal, &sb) != 0) {
466 message(LOG | CONSOLE, "device '%s' does not exist.",
470 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
474 /* Make sure the terminal will act fairly normal for us */
476 /* Setup stdout, stderr for the new process so
477 * they point to the supplied terminal */
481 /* If the init Action requires us to wait, then force the
482 * supplied terminal to be the controlling tty. */
483 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
485 /* Now fork off another process to just hang around */
486 if ((pid = fork()) < 0) {
487 message(LOG | CONSOLE, "Can't fork!");
493 /* We are the parent -- wait till the child is done */
494 signal(SIGINT, SIG_IGN);
495 signal(SIGTSTP, SIG_IGN);
496 signal(SIGQUIT, SIG_IGN);
497 signal(SIGCHLD, SIG_DFL);
499 /* Wait for child to exit */
500 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid);
502 /* See if stealing the controlling tty back is necessary */
504 if (pgrp != getpid())
507 /* Use a temporary process to steal the controlling tty. */
508 if ((pid = fork()) < 0) {
509 message(LOG | CONSOLE, "Can't fork!");
514 ioctl(0, TIOCSCTTY, 1);
517 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
518 if (tmp_pid < 0 && errno == ECHILD)
524 /* Now fall though to actually execute things */
527 /* See if any special /bin/sh requiring characters are present */
528 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
531 cmd[2] = strcat(strcpy(buf, "exec "), a->command);
534 /* Convert command (char*) into cmd (char**, one word per string) */
535 strcpy(buf, a->command);
537 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
538 if (*tmpCmd != '\0') {
549 Interactive shells want to see a dash in argv[0]. This
550 typically is handled by login, argv will be setup this
551 way if a dash appears at the front of the command path
555 if (*cmdpath == '-') {
557 /* skip over the dash */
560 /* find the last component in the command pathname */
561 s = bb_get_last_path_component(cmdpath);
563 /* make a new argv[0] */
564 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
565 message(LOG | CONSOLE, bb_msg_memory_exhausted);
569 strcpy(cmd[0] + 1, s);
573 if (a->action & ASKFIRST) {
576 * Save memory by not exec-ing anything large (like a shell)
577 * before the user wants it. This is critical if swap is not
578 * enabled and the system has low memory. Generally this will
579 * be run on the second virtual console, and the first will
580 * be allowed to start a shell or whatever an init script
583 messageD(LOG, "Waiting for enter to start '%s'"
584 "(pid %d, terminal %s)\n",
585 cmdpath, getpid(), a->terminal);
586 bb_full_write(1, press_enter, sizeof(press_enter) - 1);
587 while(read(0, &c, 1) == 1 && c != '\n')
591 /* Log the process name and args */
592 message(LOG, "Starting pid %d, console %s: '%s'",
593 getpid(), a->terminal, cmdpath);
595 #if defined CONFIG_FEATURE_INIT_COREDUMPS
596 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
599 limit.rlim_cur = RLIM_INFINITY;
600 limit.rlim_max = RLIM_INFINITY;
601 setrlimit(RLIMIT_CORE, &limit);
605 /* Now run it. The new program will take over this PID,
606 * so nothing further in init.c should be run. */
609 /* We're still here? Some error happened. */
610 message(LOG | CONSOLE, "Bummer, could not run '%s': %m", cmdpath);
613 sigprocmask(SIG_SETMASK, &omask, NULL);
617 static int waitfor(const struct init_action *a)
624 wpid = wait(&status);
625 if (wpid > 0 && wpid != pid) {
634 /* Run all commands of a particular type */
635 static void run_actions(int action)
637 struct init_action *a, *tmp;
639 for (a = init_action_list; a; a = tmp) {
641 if (a->action == action) {
642 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
644 delete_init_action(a);
645 } else if (a->action & ONCE) {
647 delete_init_action(a);
648 } else if (a->action & (RESPAWN | ASKFIRST)) {
649 /* Only run stuff with pid==0. If they have
650 * a pid, that means it is still running */
660 static void init_reboot(unsigned long magic)
663 /* We have to fork here, since the kernel calls do_exit(0) in
664 * linux/kernel/sys.c, which can cause the machint to panic when
665 * the init process is killed.... */
666 if ((pid = fork()) == 0) {
667 #if (__GNU_LIBRARY__ > 5) || defined(__dietlibc__)
670 reboot(0xfee1dead, 672274793, magic);
674 waitpid (pid, NULL, 0);
677 static void shutdown_system(void)
679 sigset_t block_signals;
681 /* run everything to be run at "shutdown". This is done _prior_
682 * to killing everything, in case people wish to use scripts to
683 * shut things down gracefully... */
684 run_actions(SHUTDOWN);
686 /* first disable all our signals */
687 sigemptyset(&block_signals);
688 sigaddset(&block_signals, SIGHUP);
689 sigaddset(&block_signals, SIGCHLD);
690 sigaddset(&block_signals, SIGUSR1);
691 sigaddset(&block_signals, SIGUSR2);
692 sigaddset(&block_signals, SIGINT);
693 sigaddset(&block_signals, SIGTERM);
694 sigaddset(&block_signals, SIGCONT);
695 sigaddset(&block_signals, SIGSTOP);
696 sigaddset(&block_signals, SIGTSTP);
697 sigprocmask(SIG_BLOCK, &block_signals, NULL);
699 /* Allow Ctrl-Alt-Del to reboot system. */
700 init_reboot(RB_ENABLE_CAD);
702 message(CONSOLE | LOG, "The system is going down NOW !!");
705 /* Send signals to every process _except_ pid 1 */
706 message(CONSOLE | LOG, "Sending SIGTERM to all processes.");
711 message(CONSOLE | LOG, "Sending SIGKILL to all processes.");
718 static void exec_signal(int sig)
720 struct init_action *a, *tmp;
721 sigset_t unblock_signals;
723 for (a = init_action_list; a; a = tmp) {
725 if (a->action & RESTART) {
728 /* unblock all signals, blocked in shutdown_system() */
729 sigemptyset(&unblock_signals);
730 sigaddset(&unblock_signals, SIGHUP);
731 sigaddset(&unblock_signals, SIGCHLD);
732 sigaddset(&unblock_signals, SIGUSR1);
733 sigaddset(&unblock_signals, SIGUSR2);
734 sigaddset(&unblock_signals, SIGINT);
735 sigaddset(&unblock_signals, SIGTERM);
736 sigaddset(&unblock_signals, SIGCONT);
737 sigaddset(&unblock_signals, SIGSTOP);
738 sigaddset(&unblock_signals, SIGTSTP);
739 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
741 messageD(CONSOLE | LOG, "Trying to re-exec %s", a->command);
742 execl(a->command, a->command, NULL);
744 message(CONSOLE | LOG, "exec of '%s' failed: %m",
748 init_reboot(RB_HALT_SYSTEM);
754 static void halt_signal(int sig)
757 message(CONSOLE | LOG,
759 /* Seems the s390 console is Wierd(tm). */
760 "The system is halted. You may reboot now."
762 "The system is halted. Press Reset or turn off power"
767 /* allow time for last message to reach serial console */
771 init_reboot(RB_POWER_OFF);
773 init_reboot(RB_HALT_SYSTEM);
778 static void reboot_signal(int sig)
781 message(CONSOLE | LOG, "Please stand by while rebooting the system.");
784 /* allow time for last message to reach serial console */
787 init_reboot(RB_AUTOBOOT);
792 static void ctrlaltdel_signal(int sig)
794 run_actions(CTRLALTDEL);
797 /* The SIGSTOP & SIGTSTP handler */
798 static void stop_handler(int sig)
800 int saved_errno = errno;
809 /* The SIGCONT handler */
810 static void cont_handler(int sig)
815 #endif /* ! DEBUG_INIT */
817 static void new_init_action(int action, char *command, const char *cons)
819 struct init_action *new_action, *a;
824 /* do not run entries if console device is not available */
825 if (access(cons, R_OK | W_OK))
827 if (strcmp(cons, "/dev/null") == 0 && (action & ASKFIRST))
830 new_action = calloc((size_t) (1), sizeof(struct init_action));
832 message(LOG | CONSOLE, "Memory allocation failure");
836 /* Append to the end of the list */
837 for (a = init_action_list; a && a->next; a = a->next);
839 a->next = new_action;
841 init_action_list = new_action;
843 strcpy(new_action->command, command);
844 new_action->action = action;
845 strcpy(new_action->terminal, cons);
846 #if 0 /* calloc zeroed always */
849 messageD(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
850 new_action->command, new_action->action, new_action->terminal);
853 static void delete_init_action(struct init_action *action)
855 struct init_action *a, *b = NULL;
857 for (a = init_action_list; a; b = a, a = a->next) {
860 init_action_list = a->next;
870 /* Make sure there is enough memory to do something useful. *
871 * Calls "swapon -a" if needed so be sure /etc/fstab is present... */
872 static void check_memory(void)
876 if (check_free_memory() > 1000)
879 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
880 if (stat("/etc/fstab", &statBuf) == 0) {
881 /* swapon -a requires /proc typically */
882 new_init_action(SYSINIT, "/bin/mount -t proc proc /proc", "");
883 /* Try to turn on swap */
884 new_init_action(SYSINIT, "/sbin/swapon -a", "");
885 run_actions(SYSINIT); /* wait and removing */
886 if (check_free_memory() < 1000)
894 message(CONSOLE, "Sorry, your computer does not have enough memory.");
898 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
899 * then parse_inittab() simply adds in some default
900 * actions(i.e., runs INIT_SCRIPT and then starts a pair
901 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
902 * _is_ defined, but /etc/inittab is missing, this
903 * results in the same set of default behaviors.
905 static void parse_inittab(void)
907 #ifdef CONFIG_FEATURE_USE_INITTAB
909 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
910 char tmpConsole[CONSOLE_BUFF_SIZE];
911 char *id, *runlev, *action, *command, *eol;
912 const struct init_action_type *a = actions;
915 file = fopen(INITTAB, "r");
917 /* No inittab file -- set up some default behavior */
919 /* Reboot on Ctrl-Alt-Del */
920 new_init_action(CTRLALTDEL, "/sbin/reboot", "");
921 /* Umount all filesystems on halt/reboot */
922 new_init_action(SHUTDOWN, "/bin/umount -a -r", "");
923 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
924 /* Swapoff on halt/reboot */
925 new_init_action(SHUTDOWN, "/sbin/swapoff -a", "");
927 /* Prepare to restart init when a HUP is received */
928 new_init_action(RESTART, "/sbin/init", "");
929 /* Askfirst shell on tty1-4 */
930 new_init_action(ASKFIRST, LOGIN_SHELL, "");
931 new_init_action(ASKFIRST, LOGIN_SHELL, VC_2);
932 new_init_action(ASKFIRST, LOGIN_SHELL, VC_3);
933 new_init_action(ASKFIRST, LOGIN_SHELL, VC_4);
935 new_init_action(SYSINIT, INIT_SCRIPT, "");
938 #ifdef CONFIG_FEATURE_USE_INITTAB
941 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
942 /* Skip leading spaces */
943 for (id = buf; *id == ' ' || *id == '\t'; id++);
945 /* Skip the line if it's a comment */
946 if (*id == '#' || *id == '\n')
949 /* Trim the trailing \n */
950 eol = strrchr(id, '\n');
954 /* Keep a copy around for posterity's sake (and error msgs) */
955 strcpy(lineAsRead, buf);
957 /* Separate the ID field from the runlevels */
958 runlev = strchr(id, ':');
959 if (runlev == NULL || *(runlev + 1) == '\0') {
960 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
967 /* Separate the runlevels from the action */
968 action = strchr(runlev, ':');
969 if (action == NULL || *(action + 1) == '\0') {
970 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
977 /* Separate the action from the command */
978 command = strchr(action, ':');
979 if (command == NULL || *(command + 1) == '\0') {
980 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
987 /* Ok, now process it */
988 for (a = actions; a->name != 0; a++) {
989 if (strcmp(a->name, action) == 0) {
991 if(strncmp(id, "/dev/", 5) == 0)
993 strcpy(tmpConsole, "/dev/");
994 safe_strncpy(tmpConsole + 5, id,
995 CONSOLE_BUFF_SIZE - 5);
998 new_init_action(a->action, command, id);
1003 /* Choke on an unknown action */
1004 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1009 #endif /* CONFIG_FEATURE_USE_INITTAB */
1013 extern int init_main(int argc, char **argv)
1015 struct init_action *a;
1019 if (argc > 1 && !strcmp(argv[1], "-q")) {
1020 return kill_init(SIGHUP);
1023 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1025 #ifdef CONFIG_FEATURE_INITRD
1026 && strstr(bb_applet_name, "linuxrc") == NULL
1031 /* Set up sig handlers -- be sure to
1032 * clear all of these in run() */
1033 signal(SIGHUP, exec_signal);
1034 signal(SIGUSR1, halt_signal);
1035 signal(SIGUSR2, halt_signal);
1036 signal(SIGINT, ctrlaltdel_signal);
1037 signal(SIGTERM, reboot_signal);
1038 signal(SIGCONT, cont_handler);
1039 signal(SIGSTOP, stop_handler);
1040 signal(SIGTSTP, stop_handler);
1042 /* Turn off rebooting via CTL-ALT-DEL -- we get a
1043 * SIGINT on CAD so we can shut things down gracefully... */
1044 init_reboot(RB_DISABLE_CAD);
1047 /* Figure out where the default console should be */
1050 /* Close whatever files are open, and reset the console. */
1055 if (device_open(console, O_RDWR | O_NOCTTY) == 0) {
1063 const char * const *e;
1064 /* Make sure environs is set to something sane */
1065 for(e = environment; *e; e++)
1066 putenv((char *) *e);
1069 message(MAYBE_CONSOLE | LOG, "init started: %s", bb_msg_full_version);
1071 /* Make sure there is enough memory to do something useful. */
1074 /* Check if we are supposed to be in single user mode */
1075 if (argc > 1 && (!strcmp(argv[1], "single") ||
1076 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1077 /* Start a shell on console */
1078 new_init_action(RESPAWN, LOGIN_SHELL, "");
1080 /* Not in single user mode -- see what inittab says */
1082 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1083 * then parse_inittab() simply adds in some default
1084 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1085 * of "askfirst" shells */
1089 /* Make the command line just say "init" -- thats all, nothing else */
1090 fixup_argv(argc, argv, "init");
1092 /* Now run everything that needs to be run */
1094 /* First run the sysinit command */
1095 run_actions(SYSINIT);
1097 /* Next run anything that wants to block */
1100 /* Next run anything to be run only once */
1103 /* If there is nothing else to do, stop */
1104 if (init_action_list == NULL) {
1105 message(LOG | CONSOLE,
1106 "No more tasks for init -- sleeping forever.");
1110 /* Now run the looping stuff for the rest of forever */
1112 /* run the respawn stuff */
1113 run_actions(RESPAWN);
1115 /* run the askfirst stuff */
1116 run_actions(ASKFIRST);
1118 /* Don't consume all CPU time -- sleep a bit */
1121 /* Wait for a child process to exit */
1122 wpid = wait(&status);
1124 /* Find out who died and clean up their corpse */
1125 for (a = init_action_list; a; a = a->next) {
1126 if (a->pid == wpid) {
1127 /* Set the pid to 0 so that the process gets
1128 * restarted by run_actions() */
1130 message(LOG, "Process '%s' (pid %d) exited. "
1131 "Scheduling it for restart.",
1135 /* see if anyone else is waiting to be reaped */
1136 wpid = waitpid (-1, &status, WNOHANG);
1143 c-file-style: "linux"