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>
50 #if defined(__UCLIBC__) && !defined(__UCLIBC_HAS_MMU__)
54 #define INIT_BUFFS_SIZE 256
56 /* From <linux/vt.h> */
58 unsigned short v_active; /* active vt */
59 unsigned short v_signal; /* signal to send */
60 unsigned short v_state; /* vt bitmask */
62 static const int VT_GETSTATE = 0x5603; /* get global vt state info */
64 /* From <linux/serial.h> */
65 struct serial_struct {
74 unsigned short close_delay;
75 char reserved_char[2];
77 unsigned short closing_wait; /* time to wait before closing */
78 unsigned short closing_wait2; /* no longer used... */
83 #if (__GNU_LIBRARY__ > 5) || defined(__dietlibc__)
84 #include <sys/reboot.h>
85 #define init_reboot(magic) reboot(magic)
87 #define init_reboot(magic) reboot(0xfee1dead, 672274793, magic)
91 #define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
94 #if defined CONFIG_FEATURE_INIT_COREDUMPS
96 * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
97 * before processes are spawned to set core file size as unlimited.
98 * This is for debugging only. Don't use this is production, unless
99 * you want core dumps lying about....
101 #define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
102 #include <sys/resource.h>
103 #include <sys/time.h>
106 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
108 #if __GNU_LIBRARY__ > 5
109 #include <sys/kdaemon.h>
111 extern int bdflush(int func, long int data);
114 #define SHELL "/bin/sh" /* Default shell */
115 #define LOGIN_SHELL "-" SHELL /* Default login shell */
116 #define INITTAB "/etc/inittab" /* inittab file location */
118 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
121 #define MAXENV 16 /* Number of env. vars */
123 /* Allowed init action types */
124 #define SYSINIT 0x001
125 #define RESPAWN 0x002
126 #define ASKFIRST 0x004
129 #define CTRLALTDEL 0x020
130 #define SHUTDOWN 0x040
131 #define RESTART 0x080
133 /* A mapping between "inittab" action name strings and action type codes. */
134 struct init_action_type {
139 static const struct init_action_type actions[] = {
140 {"sysinit", SYSINIT},
141 {"respawn", RESPAWN},
142 {"askfirst", ASKFIRST},
145 {"ctrlaltdel", CTRLALTDEL},
146 {"shutdown", SHUTDOWN},
147 {"restart", RESTART},
151 /* Set up a linked list of init_actions, to be read from inittab */
154 char command[INIT_BUFFS_SIZE];
155 char terminal[INIT_BUFFS_SIZE];
156 struct init_action *next;
160 /* Static variables */
161 static struct init_action *init_action_list = NULL;
162 static int kernelVersion = 0;
163 static char termType[32] = "TERM=linux";
164 static char console[32] = _PATH_CONSOLE;
166 #ifndef CONFIG_SYSLOGD
167 static char *log = VC_5;
169 static sig_atomic_t got_cont = 0;
170 static const int LOG = 0x1;
171 static const int CONSOLE = 0x2;
173 #if defined CONFIG_FEATURE_EXTRA_QUIET
174 static const int MAYBE_CONSOLE = 0x0;
176 #define MAYBE_CONSOLE CONSOLE
178 #ifndef RB_HALT_SYSTEM
179 static const int RB_HALT_SYSTEM = 0xcdef0123;
180 static const int RB_ENABLE_CAD = 0x89abcdef;
181 static const int RB_DISABLE_CAD = 0;
183 #define RB_POWER_OFF 0x4321fedc
184 static const int RB_AUTOBOOT = 0x01234567;
187 /* Function prototypes */
188 static void delete_init_action(struct init_action *a);
189 static int waitfor(struct init_action *a);
192 static void loop_forever(void)
198 /* Print a message to the specified device.
199 * Device may be bitwise-or'd from LOG | CONSOLE */
201 static inline messageND(int device, char *fmt, ...)
205 #define messageND message
207 static void message(int device, char *fmt, ...)
208 __attribute__ ((format(printf, 2, 3)));
209 static void message(int device, char *fmt, ...)
214 #ifdef CONFIG_SYSLOGD
216 /* Log the message to syslogd */
220 va_start(arguments, fmt);
221 vsnprintf(msg, sizeof(msg), fmt, arguments);
223 syslog_msg(LOG_USER, LOG_INFO, msg);
226 static int log_fd = -1;
228 /* Take full control of the log tty, and never close it.
229 * It's mine, all mine! Muhahahaha! */
231 if ((log_fd = device_open(log, O_RDWR | O_NDELAY)) < 0) {
233 fprintf(stderr, "Bummer, can't write to log on %s!\n", log);
236 fcntl(log_fd, F_SETFD, FD_CLOEXEC);
239 if ((device & LOG) && (log_fd >= 0)) {
240 va_start(arguments, fmt);
241 vdprintf(log_fd, fmt, arguments);
246 if (device & CONSOLE) {
247 /* Always send console messages to /dev/console so people will see them. */
249 device_open(_PATH_CONSOLE,
250 O_WRONLY | O_NOCTTY | O_NDELAY)) >= 0) {
251 va_start(arguments, fmt);
252 vdprintf(fd, fmt, arguments);
256 fprintf(stderr, "Bummer, can't print: ");
257 va_start(arguments, fmt);
258 vfprintf(stderr, fmt, arguments);
264 /* Set terminal settings to reasonable defaults */
265 static void set_term(int fd)
271 /* set control chars */
272 tty.c_cc[VINTR] = 3; /* C-c */
273 tty.c_cc[VQUIT] = 28; /* C-\ */
274 tty.c_cc[VERASE] = 127; /* C-? */
275 tty.c_cc[VKILL] = 21; /* C-u */
276 tty.c_cc[VEOF] = 4; /* C-d */
277 tty.c_cc[VSTART] = 17; /* C-q */
278 tty.c_cc[VSTOP] = 19; /* C-s */
279 tty.c_cc[VSUSP] = 26; /* C-z */
281 /* use line dicipline 0 */
284 /* Make it be sane */
285 tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
286 tty.c_cflag |= CREAD | HUPCL | CLOCAL;
290 tty.c_iflag = ICRNL | IXON | IXOFF;
293 tty.c_oflag = OPOST | ONLCR;
297 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
299 tcsetattr(fd, TCSANOW, &tty);
302 /* How much memory does this machine have?
303 Units are kBytes to avoid overflow on 4GB machines */
304 static int check_free_memory(void)
307 unsigned int result, u, s = 10;
309 if (sysinfo(&info) != 0) {
310 perror_msg("Error checking free memory");
314 /* Kernels 2.0.x and 2.2.x return info.mem_unit==0 with values in bytes.
315 * Kernels 2.4.0 return info.mem_unit in bytes. */
319 while ((u & 1) == 0 && s > 0) {
323 result = (info.totalram >> s) + (info.totalswap >> s);
330 static void console_init(void)
333 int tried_devcons = 0;
334 int tried_vtprimary = 0;
336 struct serial_struct sr;
339 if ((s = getenv("TERM")) != NULL) {
340 snprintf(termType, sizeof(termType) - 1, "TERM=%s", s);
343 if ((s = getenv("CONSOLE")) != NULL) {
344 safe_strncpy(console, s, sizeof(console));
347 /* sparc kernel supports console=tty[ab] parameter which is also
348 * passed to init, so catch it here */
349 else if ((s = getenv("console")) != NULL) {
350 /* remap tty[ab] to /dev/ttyS[01] */
351 if (strcmp(s, "ttya") == 0)
352 safe_strncpy(console, SC_0, sizeof(console));
353 else if (strcmp(s, "ttyb") == 0)
354 safe_strncpy(console, SC_1, sizeof(console));
358 /* 2.2 kernels: identify the real console backend and try to use it */
359 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
360 /* this is a serial console */
361 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
362 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
363 /* this is linux virtual tty */
364 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
366 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
371 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0) {
372 /* Can't open selected console -- try /dev/console */
373 if (!tried_devcons) {
375 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
378 /* Can't open selected console -- try vt1 */
379 if (!tried_vtprimary) {
381 safe_strncpy(console, VC_1, sizeof(console));
387 /* Perhaps we should panic here? */
388 safe_strncpy(console, "/dev/null", sizeof(console));
390 /* check for serial console */
391 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
392 /* Force the TERM setting to vt102 for serial console --
393 * if TERM is set to linux (the default) */
394 if (strcmp(termType, "TERM=linux") == 0)
395 safe_strncpy(termType, "TERM=vt102", sizeof(termType));
399 message(LOG, "console=%s\n", console);
402 static void fixup_argv(int argc, char **argv, char *new_argv0)
406 /* Fix up argv[0] to be certain we claim to be init */
407 len = strlen(argv[0]);
408 memset(argv[0], 0, len);
409 safe_strncpy(argv[0], new_argv0, len + 1);
411 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
414 memset(argv[len], 0, strlen(argv[len]));
419 /* Make sure there is enough memory to do something useful. *
420 * Calls "swapon -a" if needed so be sure /etc/fstab is present... */
421 static void check_memory(void)
425 if (check_free_memory() > 1000)
428 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
429 if (stat("/etc/fstab", &statBuf) == 0) {
430 /* swapon -a requires /proc typically */
431 system("/bin/mount -t proc proc /proc");
432 /* Try to turn on swap */
433 system("/sbin/swapon -a");
434 if (check_free_memory() < 1000)
442 message(CONSOLE, "\rSorry, your computer does not have enough memory.\n");
446 static pid_t run(struct init_action *a)
450 pid_t pid, pgrp, tmp_pid;
451 char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
452 char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
453 sigset_t nmask, omask;
454 char *environment[MAXENV + 1] = {
457 "PATH=" _PATH_STDPATH,
462 static const char press_enter[] =
463 #ifdef CUSTOMIZED_BANNER
464 #include CUSTOMIZED_BANNER
466 "\nPlease press Enter to activate this console. ";
468 /* inherit environment to the child, merging our values -andy */
469 for (i = 0; environ[i]; i++) {
470 for (j = 0; environment[j]; j++) {
471 s = strchr(environment[j], '=');
472 if (!strncmp(environ[i], environment[j], s - environment[j]))
475 if (!environment[j]) {
476 environment[j++] = environ[i];
477 environment[j] = NULL;
481 /* Block sigchild while forking. */
483 sigaddset(&nmask, SIGCHLD);
484 sigprocmask(SIG_BLOCK, &nmask, &omask);
486 if ((pid = fork()) == 0) {
491 sigprocmask(SIG_SETMASK, &omask, NULL);
493 /* Reset signal handlers that were set by the parent process */
494 signal(SIGUSR1, SIG_DFL);
495 signal(SIGUSR2, SIG_DFL);
496 signal(SIGINT, SIG_DFL);
497 signal(SIGTERM, SIG_DFL);
498 signal(SIGHUP, SIG_DFL);
499 signal(SIGCONT, SIG_DFL);
500 signal(SIGSTOP, SIG_DFL);
501 signal(SIGTSTP, SIG_DFL);
503 /* Create a new session and make ourself the process
507 /* Open the new terminal device */
508 if ((device_open(a->terminal, O_RDWR)) < 0) {
509 if (stat(a->terminal, &sb) != 0) {
510 message(LOG | CONSOLE, "\rdevice '%s' does not exist.\n",
514 message(LOG | CONSOLE, "\rBummer, can't open %s\n", a->terminal);
518 /* Make sure the terminal will act fairly normal for us */
520 /* Setup stdout, stderr for the new process so
521 * they point to the supplied terminal */
525 /* If the init Action requires us to wait, then force the
526 * supplied terminal to be the controlling tty. */
527 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
529 /* Now fork off another process to just hang around */
530 if ((pid = fork()) < 0) {
531 message(LOG | CONSOLE, "Can't fork!\n");
537 /* We are the parent -- wait till the child is done */
538 signal(SIGINT, SIG_IGN);
539 signal(SIGTSTP, SIG_IGN);
540 signal(SIGQUIT, SIG_IGN);
541 signal(SIGCHLD, SIG_DFL);
543 /* Wait for child to exit */
544 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid);
546 /* See if stealing the controlling tty back is necessary */
548 if (pgrp != getpid())
551 /* Use a temporary process to steal the controlling tty. */
552 if ((pid = fork()) < 0) {
553 message(LOG | CONSOLE, "\rCan't fork!\n");
558 ioctl(0, TIOCSCTTY, 1);
561 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
562 if (tmp_pid < 0 && errno == ECHILD)
568 /* Now fall though to actually execute things */
571 /* See if any special /bin/sh requiring characters are present */
572 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
575 strcat(strcpy(buf, "exec "), a->command);
579 /* Convert command (char*) into cmd (char**, one word per string) */
580 strcpy(buf, a->command);
582 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
583 if (*tmpCmd != '\0') {
594 Interactive shells want to see a dash in argv[0]. This
595 typically is handled by login, argv will be setup this
596 way if a dash appears at the front of the command path
600 if (*cmdpath == '-') {
602 /* skip over the dash */
605 /* find the last component in the command pathname */
606 s = get_last_path_component(cmdpath);
608 /* make a new argv[0] */
609 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
610 message(LOG | CONSOLE, "malloc failed");
614 strcpy(cmd[0] + 1, s);
618 if (a->action & ASKFIRST) {
620 * Save memory by not exec-ing anything large (like a shell)
621 * before the user wants it. This is critical if swap is not
622 * enabled and the system has low memory. Generally this will
623 * be run on the second virtual console, and the first will
624 * be allowed to start a shell or whatever an init script
628 "Waiting for enter to start '%s' (pid %d, terminal %s)\n",
629 cmdpath, getpid(), a->terminal);
630 write(fileno(stdout), press_enter, sizeof(press_enter) - 1);
634 /* Log the process name and args */
635 messageND(LOG, "Starting pid %d, console %s: '%s'\n",
636 getpid(), a->terminal, cmdpath);
638 #if defined CONFIG_FEATURE_INIT_COREDUMPS
639 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
642 limit.rlim_cur = RLIM_INFINITY;
643 limit.rlim_max = RLIM_INFINITY;
644 setrlimit(RLIMIT_CORE, &limit);
648 /* Now run it. The new program will take over this PID,
649 * so nothing further in init.c should be run. */
650 execve(cmdpath, cmd, environment);
652 /* We're still here? Some error happened. */
653 message(LOG | CONSOLE, "\rBummer, could not run '%s': %m\n", cmdpath);
656 sigprocmask(SIG_SETMASK, &omask, NULL);
660 static int waitfor(struct init_action *a)
667 wpid = wait(&status);
668 if (wpid > 0 && wpid != pid) {
677 /* Run all commands of a particular type */
678 static void run_actions(int action)
680 struct init_action *a, *tmp;
682 for (a = init_action_list; a; a = tmp) {
684 if (a->action == action) {
686 action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
688 delete_init_action(a);
689 } else if (a->action & ONCE) {
691 delete_init_action(a);
692 } else if (a->action & (RESPAWN | ASKFIRST)) {
693 /* Only run stuff with pid==0. If they have
694 * a pid, that means it is still running */
705 static void shutdown_system(void)
707 sigset_t block_signals;
709 /* run everything to be run at "shutdown". This is done _prior_
710 * to killing everything, in case people wish to use scripts to
711 * shut things down gracefully... */
712 run_actions(SHUTDOWN);
714 /* first disable all our signals */
715 sigemptyset(&block_signals);
716 sigaddset(&block_signals, SIGHUP);
717 sigaddset(&block_signals, SIGCHLD);
718 sigaddset(&block_signals, SIGUSR1);
719 sigaddset(&block_signals, SIGUSR2);
720 sigaddset(&block_signals, SIGINT);
721 sigaddset(&block_signals, SIGTERM);
722 sigaddset(&block_signals, SIGCONT);
723 sigaddset(&block_signals, SIGSTOP);
724 sigaddset(&block_signals, SIGTSTP);
725 sigprocmask(SIG_BLOCK, &block_signals, NULL);
727 /* Allow Ctrl-Alt-Del to reboot system. */
728 init_reboot(RB_ENABLE_CAD);
730 message(CONSOLE | LOG, "\n\rThe system is going down NOW !!\n");
733 /* Send signals to every process _except_ pid 1 */
734 message(CONSOLE | LOG, "\rSending SIGTERM to all processes.\n");
739 message(CONSOLE | LOG, "\rSending SIGKILL to all processes.\n");
744 if (kernelVersion > 0 && kernelVersion <= KERNEL_VERSION(2, 2, 11)) {
745 /* bdflush, kupdate not needed for kernels >2.2.11 */
751 static void exec_signal(int sig)
753 struct init_action *a, *tmp;
754 sigset_t unblock_signals;
756 for (a = init_action_list; a; a = tmp) {
758 if (a->action & RESTART) {
761 /* unblock all signals, blocked in shutdown_system() */
762 sigemptyset(&unblock_signals);
763 sigaddset(&unblock_signals, SIGHUP);
764 sigaddset(&unblock_signals, SIGCHLD);
765 sigaddset(&unblock_signals, SIGUSR1);
766 sigaddset(&unblock_signals, SIGUSR2);
767 sigaddset(&unblock_signals, SIGINT);
768 sigaddset(&unblock_signals, SIGTERM);
769 sigaddset(&unblock_signals, SIGCONT);
770 sigaddset(&unblock_signals, SIGSTOP);
771 sigaddset(&unblock_signals, SIGTSTP);
772 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
774 message(CONSOLE | LOG, "\rTrying to re-exec %s\n", a->command);
775 execl(a->command, a->command, NULL);
777 message(CONSOLE | LOG, "\rexec of '%s' failed: %m\n",
781 init_reboot(RB_HALT_SYSTEM);
787 static void halt_signal(int sig)
790 message(CONSOLE | LOG,
792 /* Seems the s390 console is Wierd(tm). */
793 "\rThe system is halted. You may reboot now.\n"
795 "\rThe system is halted. Press Reset or turn off power\n"
800 /* allow time for last message to reach serial console */
803 if (sig == SIGUSR2 && kernelVersion >= KERNEL_VERSION(2, 2, 0))
804 init_reboot(RB_POWER_OFF);
806 init_reboot(RB_HALT_SYSTEM);
811 static void reboot_signal(int sig)
814 message(CONSOLE | LOG, "\rPlease stand by while rebooting the system.\n");
817 /* allow time for last message to reach serial console */
820 init_reboot(RB_AUTOBOOT);
825 static void ctrlaltdel_signal(int sig)
827 run_actions(CTRLALTDEL);
830 /* The SIGSTOP & SIGTSTP handler */
831 static void stop_handler(int sig)
833 int saved_errno = errno;
842 /* The SIGCONT handler */
843 static void cont_handler(int sig)
848 #endif /* ! DEBUG_INIT */
850 static void new_init_action(int action, char *command, char *cons)
852 struct init_action *new_action, *a;
857 /* do not run entries if console device is not available */
858 if (access(cons, R_OK | W_OK))
860 if (strcmp(cons, "/dev/null") == 0 && (action & ASKFIRST))
863 new_action = calloc((size_t) (1), sizeof(struct init_action));
865 message(LOG | CONSOLE, "\rMemory allocation failure\n");
869 /* Append to the end of the list */
870 for (a = init_action_list; a && a->next; a = a->next);
872 a->next = new_action;
874 init_action_list = new_action;
876 strcpy(new_action->command, command);
877 new_action->action = action;
878 strcpy(new_action->terminal, cons);
880 /* message(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
881 new_action->command, new_action->action, new_action->terminal); */
884 static void delete_init_action(struct init_action *action)
886 struct init_action *a, *b = NULL;
888 for (a = init_action_list; a; b = a, a = a->next) {
891 init_action_list = a->next;
901 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
902 * then parse_inittab() simply adds in some default
903 * actions(i.e., runs INIT_SCRIPT and then starts a pair
904 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
905 * _is_ defined, but /etc/inittab is missing, this
906 * results in the same set of default behaviors.
908 static void parse_inittab(void)
910 #ifdef CONFIG_FEATURE_USE_INITTAB
912 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE],
913 tmpConsole[INIT_BUFFS_SIZE];
914 char *id, *runlev, *action, *command, *eol;
915 const struct init_action_type *a = actions;
919 file = fopen(INITTAB, "r");
921 /* No inittab file -- set up some default behavior */
923 /* Reboot on Ctrl-Alt-Del */
924 new_init_action(CTRLALTDEL, "/sbin/reboot", console);
925 /* Umount all filesystems on halt/reboot */
926 new_init_action(SHUTDOWN, "/bin/umount -a -r", console);
927 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
928 /* Swapoff on halt/reboot */
929 new_init_action(SHUTDOWN, "/sbin/swapoff -a", console);
931 /* Prepare to restart init when a HUP is received */
932 new_init_action(RESTART, "/sbin/init", console);
933 /* Askfirst shell on tty1-4 */
934 new_init_action(ASKFIRST, LOGIN_SHELL, console);
935 new_init_action(ASKFIRST, LOGIN_SHELL, VC_2);
936 new_init_action(ASKFIRST, LOGIN_SHELL, VC_3);
937 new_init_action(ASKFIRST, LOGIN_SHELL, VC_4);
939 new_init_action(SYSINIT, INIT_SCRIPT, console);
942 #ifdef CONFIG_FEATURE_USE_INITTAB
945 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
947 /* Skip leading spaces */
948 for (id = buf; *id == ' ' || *id == '\t'; id++);
950 /* Skip the line if it's a comment */
951 if (*id == '#' || *id == '\n')
954 /* Trim the trailing \n */
955 eol = strrchr(id, '\n');
959 /* Keep a copy around for posterity's sake (and error msgs) */
960 strcpy(lineAsRead, buf);
962 /* Separate the ID field from the runlevels */
963 runlev = strchr(id, ':');
964 if (runlev == NULL || *(runlev + 1) == '\0') {
965 message(LOG | CONSOLE, "\rBad inittab entry: %s\n", lineAsRead);
972 /* Separate the runlevels from the action */
973 action = strchr(runlev, ':');
974 if (action == NULL || *(action + 1) == '\0') {
975 message(LOG | CONSOLE, "\rBad inittab entry: %s\n", lineAsRead);
982 /* Separate the action from the command */
983 command = strchr(action, ':');
984 if (command == NULL || *(command + 1) == '\0') {
985 message(LOG | CONSOLE, "\rBad inittab entry: %s\n", lineAsRead);
992 /* Ok, now process it */
994 while (a->name != 0) {
995 if (strcmp(a->name, action) == 0) {
997 strcpy(tmpConsole, "/dev/");
998 strncat(tmpConsole, id, INIT_BUFFS_SIZE - 6);
1001 new_init_action(a->action, command, id);
1006 if (foundIt == TRUE)
1009 /* Choke on an unknown action */
1010 message(LOG | CONSOLE, "\rBad inittab entry: %s\n", lineAsRead);
1015 #endif /* CONFIG_FEATURE_USE_INITTAB */
1020 extern int init_main(int argc, char **argv)
1022 struct init_action *a;
1026 if (argc > 1 && !strcmp(argv[1], "-q")) {
1027 /* don't assume init's pid == 1 */
1028 long *pid = find_pid_by_name("init");
1030 if (!pid || *pid <= 0) {
1031 pid = find_pid_by_name("linuxrc");
1032 if (!pid || *pid <= 0)
1033 error_msg_and_die("no process killed");
1039 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1041 #ifdef CONFIG_FEATURE_INITRD
1042 && strstr(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 /* Make sure PATH is set to something sane */
1083 putenv("PATH=" _PATH_STDPATH);
1086 message(MAYBE_CONSOLE | LOG, "\rinit started: %s\n", full_version);
1088 /* Make sure there is enough memory to do something useful. */
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 /* Ask first then start a shell on tty2-4 */
1095 new_init_action(ASKFIRST, LOGIN_SHELL, VC_2);
1096 new_init_action(ASKFIRST, LOGIN_SHELL, VC_3);
1097 new_init_action(ASKFIRST, LOGIN_SHELL, VC_4);
1098 /* Start a shell on tty1 */
1099 new_init_action(RESPAWN, LOGIN_SHELL, console);
1101 /* Not in single user mode -- see what inittab says */
1103 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1104 * then parse_inittab() simply adds in some default
1105 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1106 * of "askfirst" shells */
1110 /* Make the command line just say "init" -- thats all, nothing else */
1111 fixup_argv(argc, argv, "init");
1113 /* Now run everything that needs to be run */
1115 /* First run the sysinit command */
1116 run_actions(SYSINIT);
1118 /* Next run anything that wants to block */
1121 /* Next run anything to be run only once */
1124 /* If there is nothing else to do, stop */
1125 if (init_action_list == NULL) {
1126 message(LOG | CONSOLE,
1127 "\rNo more tasks for init -- sleeping forever.\n");
1131 /* Now run the looping stuff for the rest of forever */
1133 /* run the respawn stuff */
1134 run_actions(RESPAWN);
1136 /* run the askfirst stuff */
1137 run_actions(ASKFIRST);
1139 /* Don't consume all CPU time -- sleep a bit */
1142 /* Wait for a child process to exit */
1143 wpid = wait(&status);
1145 /* Find out who died and clean up their corpse */
1146 for (a = init_action_list; a; a = a->next) {
1147 if (a->pid == wpid) {
1148 /* Set the pid to 0 so that the process gets
1149 * restarted by run_actions() */
1151 message(LOG, "Process '%s' (pid %d) exited. "
1152 "Scheduling it for restart.\n", a->command, wpid);
1161 c-file-style: "linux"