1 /* vi: set sw=4 ts=4: */
3 * Mini init implementation for busybox
6 * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
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>
51 /* From <linux/vt.h> */
53 unsigned short v_active; /* active vt */
54 unsigned short v_signal; /* signal to send */
55 unsigned short v_state; /* vt bitmask */
57 static const int VT_GETSTATE = 0x5603; /* get global vt state info */
59 /* From <linux/serial.h> */
60 struct serial_struct {
69 unsigned short close_delay;
70 char reserved_char[2];
72 unsigned short closing_wait; /* time to wait before closing */
73 unsigned short closing_wait2; /* no longer used... */
78 #if (__GNU_LIBRARY__ > 5) || defined(__dietlibc__)
79 #include <sys/reboot.h>
80 #define init_reboot(magic) reboot(magic)
82 #define init_reboot(magic) reboot(0xfee1dead, 672274793, magic)
85 #ifndef RB_HALT_SYSTEM
86 static const int RB_HALT_SYSTEM = 0xcdef0123;
87 static const int RB_ENABLE_CAD = 0x89abcdef;
88 static const int RB_DISABLE_CAD = 0;
89 #define RB_POWER_OFF 0x4321fedc
90 static const int RB_AUTOBOOT = 0x01234567;
94 #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 #if __GNU_LIBRARY__ > 5
113 #include <sys/kdaemon.h>
115 extern int bdflush (int func, long int data);
119 #define SHELL "/bin/sh" /* Default shell */
120 #define LOGIN_SHELL "-" SHELL /* Default login shell */
121 #define INITTAB "/etc/inittab" /* inittab file location */
123 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
126 #define MAXENV 16 /* Number of env. vars */
127 //static const int MAXENV = 16; /* Number of env. vars */
128 static const int LOG = 0x1;
129 static const int CONSOLE = 0x2;
130 #if defined BB_FEATURE_EXTRA_QUIET
131 static const int MAYBE_CONSOLE = 0x0;
133 #define MAYBE_CONSOLE CONSOLE
137 /* Allowed init action types */
149 /* A mapping between "inittab" action name strings and action type codes. */
150 typedef struct initActionType {
152 initActionEnum action;
155 static const struct initActionType actions[] = {
156 {"sysinit", SYSINIT},
157 {"respawn", RESPAWN},
158 {"askfirst", ASKFIRST},
161 {"ctrlaltdel", CTRLALTDEL},
162 {"shutdown", SHUTDOWN},
163 {"restart", RESTART},
167 /* Set up a linked list of initActions, to be read from inittab */
168 typedef struct initActionTag initAction;
169 struct initActionTag {
174 initActionEnum action;
176 static initAction *initActionList = NULL;
179 static char *secondConsole = VC_2;
180 static char *thirdConsole = VC_3;
181 static char *fourthConsole = VC_4;
182 static char *log = VC_5;
183 static int kernelVersion = 0;
184 static char termType[32] = "TERM=linux";
185 static char console[32] = _PATH_CONSOLE;
186 sig_atomic_t got_cont = 0;
188 static void delete_initAction(initAction * action);
190 static void loop_forever(void)
196 /* Print a message to the specified device.
197 * Device may be bitwise-or'd from LOG | CONSOLE */
199 static inline messageND(int device, char *fmt, ...) { }
201 #define messageND message
203 static void message(int device, char *fmt, ...)
204 __attribute__ ((format (printf, 2, 3)));
205 static void message(int device, char *fmt, ...)
210 #ifdef CONFIG_SYSLOGD
212 /* Log the message to syslogd */
216 va_start(arguments, fmt);
217 vsnprintf(msg, sizeof(msg), fmt, arguments);
219 syslog_msg(LOG_USER, LOG_USER|LOG_INFO, msg);
222 static int log_fd = -1;
224 /* Take full control of the log tty, and never close it.
225 * It's mine, all mine! Muhahahaha! */
228 /* don't even try to log, because there is no such console */
230 /* log to main console instead */
232 } else if ((log_fd = device_open(log, O_RDWR|O_NDELAY)) < 0) {
234 fprintf(stderr, "Bummer, can't write to log on %s!\n", log);
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. */
250 device_open(_PATH_CONSOLE,
251 O_WRONLY | O_NOCTTY | O_NDELAY)) >= 0) {
252 va_start(arguments, fmt);
253 vdprintf(fd, fmt, arguments);
257 fprintf(stderr, "Bummer, can't print: ");
258 va_start(arguments, fmt);
259 vfprintf(stderr, fmt, arguments);
265 /* Set terminal settings to reasonable defaults */
266 static void set_term(int fd)
272 /* set control chars */
273 tty.c_cc[VINTR] = 3; /* C-c */
274 tty.c_cc[VQUIT] = 28; /* C-\ */
275 tty.c_cc[VERASE] = 127; /* C-? */
276 tty.c_cc[VKILL] = 21; /* C-u */
277 tty.c_cc[VEOF] = 4; /* C-d */
278 tty.c_cc[VSTART] = 17; /* C-q */
279 tty.c_cc[VSTOP] = 19; /* C-s */
280 tty.c_cc[VSUSP] = 26; /* C-z */
282 /* use line dicipline 0 */
285 /* Make it be sane */
286 tty.c_cflag &= CBAUD|CBAUDEX|CSIZE|CSTOPB|PARENB|PARODD;
287 tty.c_cflag |= CREAD|HUPCL|CLOCAL;
291 tty.c_iflag = ICRNL | IXON | IXOFF;
294 tty.c_oflag = OPOST | ONLCR;
298 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
300 tcsetattr(fd, TCSANOW, &tty);
303 /* How much memory does this machine have?
304 Units are kBytes to avoid overflow on 4GB machines */
305 static int check_free_memory(void)
308 unsigned int result, u, s=10;
310 if (sysinfo(&info) != 0) {
311 perror_msg("Error checking free memory");
315 /* Kernels 2.0.x and 2.2.x return info.mem_unit==0 with values in bytes.
316 * Kernels 2.4.0 return info.mem_unit in bytes. */
319 while ( (u&1) == 0 && s > 0 ) { u>>=1; s--; }
320 result = (info.totalram>>s) + (info.totalswap>>s);
322 if (result < 0) result = INT_MAX;
326 static void console_init(void)
329 int tried_devcons = 0;
330 int tried_vtprimary = 0;
332 struct serial_struct sr;
335 if ((s = getenv("TERM")) != NULL) {
336 snprintf(termType, sizeof(termType) - 1, "TERM=%s", s);
339 if ((s = getenv("CONSOLE")) != NULL) {
340 safe_strncpy(console, s, sizeof(console));
343 /* sparc kernel supports console=tty[ab] parameter which is also
344 * passed to init, so catch it here */
345 else if ((s = getenv("console")) != NULL) {
346 /* remap tty[ab] to /dev/ttyS[01] */
347 if (strcmp(s, "ttya") == 0)
348 safe_strncpy(console, SC_0, sizeof(console));
349 else if (strcmp(s, "ttyb") == 0)
350 safe_strncpy(console, SC_1, sizeof(console));
354 /* 2.2 kernels: identify the real console backend and try to use it */
355 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
356 /* this is a serial console */
357 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
358 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
359 /* this is linux virtual tty */
360 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
362 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
367 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0) {
368 /* Can't open selected console -- try /dev/console */
369 if (!tried_devcons) {
371 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
374 /* Can't open selected console -- try vt1 */
375 if (!tried_vtprimary) {
377 safe_strncpy(console, VC_1, sizeof(console));
383 /* Perhaps we should panic here? */
384 safe_strncpy(console, "/dev/null", sizeof(console));
386 /* check for serial console and disable logging to tty5 & running a
388 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
390 secondConsole = NULL;
392 fourthConsole = NULL;
393 /* Force the TERM setting to vt102 for serial console --
394 * iff TERM is set to linux (the default) */
395 if (strcmp( termType, "TERM=linux" ) == 0)
396 safe_strncpy(termType, "TERM=vt102", sizeof(termType));
397 message(LOG | CONSOLE,
398 "serial console detected. Disabling virtual terminals.\n");
402 message(LOG, "console=%s\n", console);
405 static void fixup_argv(int argc, char **argv, char *new_argv0)
408 /* Fix up argv[0] to be certain we claim to be init */
409 len = strlen(argv[0]);
410 memset(argv[0], 0, len);
411 safe_strncpy(argv[0], new_argv0, len + 1);
413 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
416 memset(argv[len], 0, strlen(argv[len]));
422 static pid_t run(char *command, char *terminal, int get_enter)
428 char *cmd[255], *cmdpath;
431 static const char press_enter[] =
433 #ifdef CUSTOMIZED_BANNER
434 #include CUSTOMIZED_BANNER
437 "\nPlease press Enter to activate this console. ";
438 char *environment[MAXENV+1] = {
441 "PATH=" _PATH_STDPATH,
447 /* inherit environment to the child, merging our values -andy */
448 for (i=0; environ[i]; i++) {
449 for (j=0; environment[j]; j++) {
450 s = strchr(environment[j], '=');
451 if (!strncmp(environ[i], environment[j], s - environment[j]))
454 if (!environment[j]) {
455 environment[j++] = environ[i];
456 environment[j] = NULL;
460 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
461 if ((pid = fork()) == 0)
463 if ((pid = vfork()) == 0)
467 ioctl(0, TIOCNOTTY, 0);
473 /* Reset signal handlers set for parent process */
474 signal(SIGUSR1, SIG_DFL);
475 signal(SIGUSR2, SIG_DFL);
476 signal(SIGINT, SIG_DFL);
477 signal(SIGTERM, SIG_DFL);
478 signal(SIGHUP, SIG_DFL);
479 signal(SIGCONT, SIG_DFL);
480 signal(SIGSTOP, SIG_DFL);
481 signal(SIGTSTP, SIG_DFL);
483 if ((fd = device_open(terminal, O_RDWR)) < 0) {
484 if (stat(terminal, &sb) != 0) {
485 message(LOG | CONSOLE, "device '%s' does not exist.\n",
489 message(LOG | CONSOLE, "Bummer, can't open %s\n", terminal);
495 ioctl(0, TIOCSCTTY, 1);
496 tcsetpgrp(0, getpgrp());
499 /* See if any special /bin/sh requiring characters are present */
500 if (strpbrk(command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
503 strcpy(buf, "exec ");
504 safe_strncpy(buf + sizeof("exec "), command,
505 sizeof(buf) - sizeof("exec "));
509 /* Convert command (char*) into cmd (char**, one word per string) */
510 safe_strncpy(buf, command, sizeof(buf));
512 for (tmpCmd = buf, i = 0;
513 (tmpCmd = strsep(&s, " \t")) != NULL;) {
514 if (*tmpCmd != '\0') {
526 Interactive shells want to see a dash in argv[0]. This
527 typically is handled by login, argv will be setup this
528 way if a dash appears at the front of the command path
532 if (*cmdpath == '-') {
534 /* skip over the dash */
537 /* find the last component in the command pathname */
538 s = get_last_path_component(cmdpath);
540 /* make a new argv[0] */
541 if ((cmd[0] = malloc(strlen(s)+2)) == NULL) {
542 message(LOG | CONSOLE, "malloc failed");
552 * Save memory by not exec-ing anything large (like a shell)
553 * before the user wants it. This is critical if swap is not
554 * enabled and the system has low memory. Generally this will
555 * be run on the second virtual console, and the first will
556 * be allowed to start a shell or whatever an init script
559 messageND(LOG, "Waiting for enter to start '%s' (pid %d, console %s)\n",
560 cmd[0], getpid(), terminal);
561 write(fileno(stdout), press_enter, sizeof(press_enter) - 1);
565 /* Log the process name and args */
566 messageND(LOG, "Starting pid %d, console %s: '%s'\n",
567 getpid(), terminal, command);
569 #if defined CONFIG_FEATURE_INIT_COREDUMPS
570 if (stat (CORE_ENABLE_FLAG_FILE, &sb) == 0) {
572 limit.rlim_cur = RLIM_INFINITY;
573 limit.rlim_max = RLIM_INFINITY;
574 setrlimit(RLIMIT_CORE, &limit);
578 /* Now run it. The new program will take over this PID,
579 * so nothing further in init.c should be run. */
580 execve(cmdpath, cmd, environment);
582 /* We're still here? Some error happened. */
583 message(LOG | CONSOLE, "Bummer, could not run '%s': %s\n", cmdpath,
590 static int waitfor(char *command, char *terminal, int get_enter)
593 int pid = run(command, terminal, get_enter);
596 wpid = wait(&status);
597 if (wpid > 0 && wpid != pid) {
606 /* Make sure there is enough memory to do something useful. *
607 * Calls "swapon -a" if needed so be sure /etc/fstab is present... */
608 static void check_memory(void)
612 if (check_free_memory() > 1000)
615 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
616 if (stat("/etc/fstab", &statBuf) == 0) {
617 /* swapon -a requires /proc typically */
618 waitfor("/bin/mount -t proc proc /proc", console, FALSE);
619 /* Try to turn on swap */
620 waitfor("/sbin/swapon -a", console, FALSE);
621 if (check_free_memory() < 1000)
630 "Sorry, your computer does not have enough memory.\n");
634 /* Run all commands to be run right before halt/reboot */
635 static void run_actions(initActionEnum action)
638 for (a = initActionList; a; a = tmp) {
640 if (a->action == action) {
641 waitfor(a->process, a->console, FALSE);
642 delete_initAction(a);
649 static void shutdown_system(void)
651 sigset_t block_signals;
653 /* first disable all our signals */
654 sigemptyset(&block_signals);
655 sigaddset(&block_signals, SIGHUP);
656 sigaddset(&block_signals, SIGCHLD);
657 sigaddset(&block_signals, SIGUSR1);
658 sigaddset(&block_signals, SIGUSR2);
659 sigaddset(&block_signals, SIGINT);
660 sigaddset(&block_signals, SIGTERM);
661 sigaddset(&block_signals, SIGCONT);
662 sigaddset(&block_signals, SIGSTOP);
663 sigaddset(&block_signals, SIGTSTP);
664 sigprocmask(SIG_BLOCK, &block_signals, NULL);
666 /* Allow Ctrl-Alt-Del to reboot system. */
667 init_reboot(RB_ENABLE_CAD);
669 message(CONSOLE|LOG, "\nThe system is going down NOW !!\n");
672 /* Send signals to every process _except_ pid 1 */
673 message(CONSOLE|LOG, "Sending SIGTERM to all processes.\n");
678 message(CONSOLE|LOG, "Sending SIGKILL to all processes.\n");
682 /* run everything to be run at "shutdown" */
683 run_actions(SHUTDOWN);
686 if (kernelVersion > 0 && kernelVersion <= KERNEL_VERSION(2,2,11)) {
687 /* bdflush, kupdate not needed for kernels >2.2.11 */
693 static void exec_signal(int sig)
696 for (a = initActionList; a; a = tmp) {
698 if (a->action == RESTART) {
700 message(CONSOLE|LOG, "Trying to re-exec %s\n", a->process);
701 execl(a->process, a->process, NULL);
703 message(CONSOLE|LOG, "execl of %s failed: %s\n",
704 a->process, sys_errlist[errno]);
707 init_reboot(RB_HALT_SYSTEM);
713 static void halt_signal(int sig)
718 /* Seems the s390 console is Wierd(tm). */
719 "The system is halted. You may reboot now.\n"
721 /* secondConsole is NULL for a serial console */
722 "The system is halted. Press %s or turn off power\n",
723 (secondConsole == NULL)? "Reset" : "CTRL-ALT-DEL"
728 /* allow time for last message to reach serial console */
731 if (sig == SIGUSR2 && kernelVersion >= KERNEL_VERSION(2,2,0))
732 init_reboot(RB_POWER_OFF);
734 init_reboot(RB_HALT_SYSTEM);
739 static void reboot_signal(int sig)
742 message(CONSOLE|LOG, "Please stand by while rebooting the system.\n");
745 /* allow time for last message to reach serial console */
748 init_reboot(RB_AUTOBOOT);
753 static void ctrlaltdel_signal(int sig)
755 run_actions(CTRLALTDEL);
759 * The SIGSTOP & SIGTSTP handler
761 static void stop_handler(int sig)
763 int saved_errno = errno;
766 while(!got_cont) pause();
772 * The SIGCONT handler
774 static void cont_handler(int sig)
779 #endif /* ! DEBUG_INIT */
781 static void new_initAction(initActionEnum action, char *process, char *cons)
783 initAction *newAction;
789 /* If BusyBox detects that a serial console is in use,
790 * then entries not refering to the console or null devices will _not_ be run.
791 * The exception to this rule is the null device.
793 if (secondConsole == NULL && strcmp(cons, console)
794 && strcmp(cons, "/dev/null"))
796 if (strcmp(cons, "/dev/null") == 0 && action == ASKFIRST)
799 newAction = calloc((size_t) (1), sizeof(initAction));
801 message(LOG | CONSOLE, "Memory allocation failure\n");
804 for (a = initActionList; a && a->nextPtr; a = a->nextPtr) ;
806 a->nextPtr = newAction;
808 initActionList = newAction;
810 safe_strncpy(newAction->process, process, 255);
811 newAction->action = action;
812 safe_strncpy(newAction->console, cons, 255);
814 // message(LOG|CONSOLE, "process='%s' action='%d' console='%s'\n",
815 // newAction->process, newAction->action, newAction->console);
818 static void delete_initAction(initAction * action)
820 initAction *a, *b = NULL;
822 for (a = initActionList; a; b = a, a = a->nextPtr) {
825 initActionList = a->nextPtr;
827 b->nextPtr = a->nextPtr;
835 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
836 * then parse_inittab() simply adds in some default
837 * actions(i.e., runs INIT_SCRIPT and then starts a pair
838 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
839 * _is_ defined, but /etc/inittab is missing, this
840 * results in the same set of default behaviors.
842 static void parse_inittab(void)
844 #ifdef CONFIG_FEATURE_USE_INITTAB
846 char buf[256], lineAsRead[256], tmpConsole[256];
847 char *id, *runlev, *action, *process, *eol;
848 const struct initActionType *a = actions;
852 file = fopen(INITTAB, "r");
854 /* No inittab file -- set up some default behavior */
856 /* Reboot on Ctrl-Alt-Del */
857 new_initAction(CTRLALTDEL, "/sbin/reboot", console);
858 /* Umount all filesystems on halt/reboot */
859 new_initAction(SHUTDOWN, "/bin/umount -a -r", console);
860 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
861 /* Swapoff on halt/reboot */
862 new_initAction(SHUTDOWN, "/sbin/swapoff -a", console);
864 /* Prepare to restart init when a HUP is received */
865 new_initAction(RESTART, "/sbin/init", console);
866 /* Askfirst shell on tty1 */
867 new_initAction(ASKFIRST, LOGIN_SHELL, console);
868 /* Askfirst shell on tty2 */
869 if (secondConsole != NULL)
870 new_initAction(ASKFIRST, LOGIN_SHELL, secondConsole);
871 /* Askfirst shell on tty3 */
872 if (thirdConsole != NULL)
873 new_initAction(ASKFIRST, LOGIN_SHELL, thirdConsole);
874 /* Askfirst shell on tty4 */
875 if (fourthConsole != NULL)
876 new_initAction(ASKFIRST, LOGIN_SHELL, fourthConsole);
878 new_initAction(SYSINIT, INIT_SCRIPT, console);
881 #ifdef CONFIG_FEATURE_USE_INITTAB
884 while (fgets(buf, 255, file) != NULL) {
886 /* Skip leading spaces */
887 for (id = buf; *id == ' ' || *id == '\t'; id++);
889 /* Skip the line if it's a comment */
890 if (*id == '#' || *id == '\n')
893 /* Trim the trailing \n */
894 eol = strrchr(id, '\n');
898 /* Keep a copy around for posterity's sake (and error msgs) */
899 strcpy(lineAsRead, buf);
901 /* Separate the ID field from the runlevels */
902 runlev = strchr(id, ':');
903 if (runlev == NULL || *(runlev + 1) == '\0') {
904 message(LOG | CONSOLE, "Bad inittab entry: %s\n", lineAsRead);
911 /* Separate the runlevels from the action */
912 action = strchr(runlev, ':');
913 if (action == NULL || *(action + 1) == '\0') {
914 message(LOG | CONSOLE, "Bad inittab entry: %s\n", lineAsRead);
921 /* Separate the action from the process */
922 process = strchr(action, ':');
923 if (process == NULL || *(process + 1) == '\0') {
924 message(LOG | CONSOLE, "Bad inittab entry: %s\n", lineAsRead);
931 /* Ok, now process it */
933 while (a->name != 0) {
934 if (strcmp(a->name, action) == 0) {
936 strcpy(tmpConsole, "/dev/");
937 strncat(tmpConsole, id, 200);
940 new_initAction(a->action, process, id);
948 /* Choke on an unknown action */
949 message(LOG | CONSOLE, "Bad inittab entry: %s\n", lineAsRead);
953 #endif /* CONFIG_FEATURE_USE_INITTAB */
958 extern int init_main(int argc, char **argv)
965 if (argc > 1 && !strcmp(argv[1], "-q")) {
971 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
973 #ifdef CONFIG_FEATURE_INITRD
974 && strstr(applet_name, "linuxrc") == NULL
980 /* Set up sig handlers -- be sure to
981 * clear all of these in run() */
982 signal(SIGHUP, exec_signal);
983 signal(SIGUSR1, halt_signal);
984 signal(SIGUSR2, halt_signal);
985 signal(SIGINT, ctrlaltdel_signal);
986 signal(SIGTERM, reboot_signal);
987 signal(SIGCONT, cont_handler);
988 signal(SIGSTOP, stop_handler);
989 signal(SIGTSTP, stop_handler);
991 /* Turn off rebooting via CTL-ALT-DEL -- we get a
992 * SIGINT on CAD so we can shut things down gracefully... */
993 init_reboot(RB_DISABLE_CAD);
996 /* Figure out what kernel this is running */
997 kernelVersion = get_kernel_revision();
999 /* Close whatever files are open, and reset the console. */
1004 /* Figure out where the default console should be */
1011 /* Make sure PATH is set to something sane */
1012 putenv("PATH="_PATH_STDPATH);
1015 message(MAYBE_CONSOLE|LOG, "init started: %s\n", full_version);
1017 /* Make sure there is enough memory to do something useful. */
1020 /* Check if we are supposed to be in single user mode */
1021 if (argc > 1 && (!strcmp(argv[1], "single") ||
1022 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1023 /* Ask first then start a shell on tty2-4 */
1024 if (secondConsole != NULL)
1025 new_initAction(ASKFIRST, LOGIN_SHELL, secondConsole);
1026 if (thirdConsole != NULL)
1027 new_initAction(ASKFIRST, LOGIN_SHELL, thirdConsole);
1028 if (fourthConsole != NULL)
1029 new_initAction(ASKFIRST, LOGIN_SHELL, fourthConsole);
1030 /* Start a shell on tty1 */
1031 new_initAction(RESPAWN, LOGIN_SHELL, console);
1033 /* Not in single user mode -- see what inittab says */
1035 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1036 * then parse_inittab() simply adds in some default
1037 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1038 * of "askfirst" shells */
1042 /* Make the command line just say "init" -- thats all, nothing else */
1043 fixup_argv(argc, argv, "init");
1045 /* Now run everything that needs to be run */
1047 /* First run the sysinit command */
1048 run_actions(SYSINIT);
1049 /* Next run anything that wants to block */
1051 /* Next run anything to be run only once */
1052 for (a = initActionList; a; a = tmp) {
1054 if (a->action == ONCE) {
1055 run(a->process, a->console, FALSE);
1056 /* Now remove the "once" entry from the list */
1057 delete_initAction(a);
1060 /* If there is nothing else to do, stop */
1061 if (initActionList == NULL) {
1062 message(LOG | CONSOLE,
1063 "No more tasks for init -- sleeping forever.\n");
1067 /* Now run the looping stuff for the rest of forever */
1069 for (a = initActionList; a; a = a->nextPtr) {
1070 /* Only run stuff with pid==0. If they have
1071 * a pid, that means they are still running */
1073 switch (a->action) {
1075 /* run the respawn stuff */
1076 a->pid = run(a->process, a->console, FALSE);
1079 /* run the askfirst stuff */
1080 a->pid = run(a->process, a->console, TRUE);
1082 /* silence the compiler's incessant whining */
1088 /* Wait for a child process to exit */
1089 wpid = wait(&status);
1091 /* Find out who died and clean up their corpse */
1092 for (a = initActionList; a; a = a->nextPtr) {
1093 if (a->pid == wpid) {
1095 message(LOG, "Process '%s' (pid %d) exited. Scheduling it for restart.\n",
1106 c-file-style: "linux"