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 char *secondConsole = VC_2;
163 static char *thirdConsole = VC_3;
164 static char *fourthConsole = VC_4;
165 static char *log = VC_5;
166 static int kernelVersion = 0;
167 static char termType[32] = "TERM=linux";
168 static char console[32] = _PATH_CONSOLE;
169 static sig_atomic_t got_cont = 0;
170 static const int LOG = 0x1;
171 static const int CONSOLE = 0x2;
172 #if defined CONFIG_FEATURE_EXTRA_QUIET
173 static const int MAYBE_CONSOLE = 0x0;
175 #define MAYBE_CONSOLE CONSOLE
177 #ifndef RB_HALT_SYSTEM
178 static const int RB_HALT_SYSTEM = 0xcdef0123;
179 static const int RB_ENABLE_CAD = 0x89abcdef;
180 static const int RB_DISABLE_CAD = 0;
181 #define RB_POWER_OFF 0x4321fedc
182 static const int RB_AUTOBOOT = 0x01234567;
185 /* Function prototypes */
186 static void delete_init_action(struct init_action *a);
187 static int waitfor(struct init_action *a);
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, ...) __attribute__ ((format (printf, 2, 3)));
204 static void message(int device, char *fmt, ...)
209 #ifdef CONFIG_SYSLOGD
211 /* Log the message to syslogd */
215 va_start(arguments, fmt);
216 vsnprintf(msg, sizeof(msg), fmt, arguments);
218 syslog_msg(LOG_USER, LOG_INFO, msg);
221 static int log_fd = -1;
223 /* Take full control of the log tty, and never close it.
224 * It's mine, all mine! Muhahahaha! */
227 /* don't even try to log, because there is no such console */
229 /* log to main console instead */
231 } else if ((log_fd = device_open(log, O_RDWR|O_NDELAY)) < 0) {
233 fprintf(stderr, "Bummer, can't write to log on %s!\n", log);
238 if ((device & LOG) && (log_fd >= 0)) {
239 va_start(arguments, fmt);
240 vdprintf(log_fd, fmt, arguments);
245 if (device & CONSOLE) {
246 /* Always send console messages to /dev/console so people will see them. */
249 device_open(_PATH_CONSOLE, O_WRONLY | O_NOCTTY | O_NDELAY)) >= 0) {
250 va_start(arguments, fmt);
251 vdprintf(fd, fmt, arguments);
255 fprintf(stderr, "Bummer, can't print: ");
256 va_start(arguments, fmt);
257 vfprintf(stderr, fmt, arguments);
263 /* Set terminal settings to reasonable defaults */
264 static void set_term(int fd)
270 /* set control chars */
271 tty.c_cc[VINTR] = 3; /* C-c */
272 tty.c_cc[VQUIT] = 28; /* C-\ */
273 tty.c_cc[VERASE] = 127; /* C-? */
274 tty.c_cc[VKILL] = 21; /* C-u */
275 tty.c_cc[VEOF] = 4; /* C-d */
276 tty.c_cc[VSTART] = 17; /* C-q */
277 tty.c_cc[VSTOP] = 19; /* C-s */
278 tty.c_cc[VSUSP] = 26; /* C-z */
280 /* use line dicipline 0 */
283 /* Make it be sane */
284 tty.c_cflag &= CBAUD|CBAUDEX|CSIZE|CSTOPB|PARENB|PARODD;
285 tty.c_cflag |= CREAD|HUPCL|CLOCAL;
289 tty.c_iflag = ICRNL | IXON | IXOFF;
292 tty.c_oflag = OPOST | ONLCR;
296 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
298 tcsetattr(fd, TCSANOW, &tty);
301 /* How much memory does this machine have?
302 Units are kBytes to avoid overflow on 4GB machines */
303 static int check_free_memory(void)
306 unsigned int result, u, s=10;
308 if (sysinfo(&info) != 0) {
309 perror_msg("Error checking free memory");
313 /* Kernels 2.0.x and 2.2.x return info.mem_unit==0 with values in bytes.
314 * Kernels 2.4.0 return info.mem_unit in bytes. */
317 while ( (u&1) == 0 && s > 0 ) { u>>=1; s--; }
318 result = (info.totalram>>s) + (info.totalswap>>s);
320 if (result < 0) result = INT_MAX;
324 static void console_init(void)
327 int tried_devcons = 0;
328 int tried_vtprimary = 0;
330 struct serial_struct sr;
333 if ((s = getenv("TERM")) != NULL) {
334 snprintf(termType, sizeof(termType) - 1, "TERM=%s", s);
337 if ((s = getenv("CONSOLE")) != NULL) {
338 safe_strncpy(console, s, sizeof(console));
341 /* sparc kernel supports console=tty[ab] parameter which is also
342 * passed to init, so catch it here */
343 else if ((s = getenv("console")) != NULL) {
344 /* remap tty[ab] to /dev/ttyS[01] */
345 if (strcmp(s, "ttya") == 0)
346 safe_strncpy(console, SC_0, sizeof(console));
347 else if (strcmp(s, "ttyb") == 0)
348 safe_strncpy(console, SC_1, sizeof(console));
352 /* 2.2 kernels: identify the real console backend and try to use it */
353 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
354 /* this is a serial console */
355 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
356 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
357 /* this is linux virtual tty */
358 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
360 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
365 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0) {
366 /* Can't open selected console -- try /dev/console */
367 if (!tried_devcons) {
369 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
372 /* Can't open selected console -- try vt1 */
373 if (!tried_vtprimary) {
375 safe_strncpy(console, VC_1, sizeof(console));
381 /* Perhaps we should panic here? */
382 safe_strncpy(console, "/dev/null", sizeof(console));
384 /* check for serial console and disable logging to tty5 &
385 * running a shell to tty2-4 */
386 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
388 secondConsole = NULL;
390 fourthConsole = NULL;
391 /* Force the TERM setting to vt102 for serial console --
392 * iff TERM is set to linux (the default) */
393 if (strcmp( termType, "TERM=linux" ) == 0)
394 safe_strncpy(termType, "TERM=vt102", sizeof(termType));
395 message(LOG | CONSOLE,
396 "\rserial console detected. Disabling virtual terminals.\n");
400 message(LOG, "console=%s\n", console);
403 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)
443 "\rSorry, your computer does not have enough memory.\n");
447 static pid_t run(struct init_action *a)
451 pid_t pid, pgrp, tmp_pid;
452 char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
453 char buf[INIT_BUFFS_SIZE+6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
454 sigset_t nmask, omask;
455 char *environment[MAXENV+1] = {
458 "PATH=" _PATH_STDPATH,
463 static const char press_enter[] =
464 #ifdef CUSTOMIZED_BANNER
465 #include CUSTOMIZED_BANNER
467 "\nPlease press Enter to activate this console. ";
469 /* inherit environment to the child, merging our values -andy */
470 for (i=0; environ[i]; i++) {
471 for (j=0; environment[j]; j++) {
472 s = strchr(environment[j], '=');
473 if (!strncmp(environ[i], environment[j], s - environment[j]))
476 if (!environment[j]) {
477 environment[j++] = environ[i];
478 environment[j] = NULL;
482 /* Block sigchild while forking. */
484 sigaddset(&nmask, SIGCHLD);
485 sigprocmask(SIG_BLOCK, &nmask, &omask);
487 if ((pid = fork()) == 0)
493 sigprocmask(SIG_SETMASK, &omask, NULL);
495 /* Reset signal handlers that were set by the parent process */
496 signal(SIGUSR1, SIG_DFL);
497 signal(SIGUSR2, SIG_DFL);
498 signal(SIGINT, SIG_DFL);
499 signal(SIGTERM, SIG_DFL);
500 signal(SIGHUP, SIG_DFL);
501 signal(SIGCONT, SIG_DFL);
502 signal(SIGSTOP, SIG_DFL);
503 signal(SIGTSTP, SIG_DFL);
505 /* Create a new session and make ourself the process
506 * group leader for non-interactive jobs */
507 if ((a->action & (RESPAWN))==0)
510 /* Open the new terminal device */
511 if ((device_open(a->terminal, O_RDWR|O_NOCTTY)) < 0) {
512 if (stat(a->terminal, &sb) != 0) {
513 message(LOG | CONSOLE, "\rdevice '%s' does not exist.\n",
517 message(LOG | CONSOLE, "\rBummer, can't open %s\n", a->terminal);
521 /* Non-interactive jobs should not get a controling tty */
522 if ((a->action & (RESPAWN))==0)
523 (void)ioctl(0, TIOCSCTTY, 0);
525 /* Make sure the terminal will act fairly normal for us */
527 /* Setup stdout, stderr for the new process so
528 * they point to the supplied terminal */
532 /* For interactive jobs, create a new session
533 * and become the process group leader */
534 if ((a->action & (RESPAWN)))
537 /* If the init Action requires us to wait, then force the
538 * supplied terminal to be the controlling tty. */
539 if (a->action & (SYSINIT|WAIT|CTRLALTDEL|SHUTDOWN|RESTART)) {
541 /* Now fork off another process to just hang around */
542 if ((pid = fork()) < 0) {
543 message(LOG | CONSOLE, "Can't fork!\n");
549 /* We are the parent -- wait till the child is done */
550 signal(SIGINT, SIG_IGN);
551 signal(SIGTSTP, SIG_IGN);
552 signal(SIGQUIT, SIG_IGN);
553 signal(SIGCHLD, SIG_DFL);
555 /* Wait for child to exit */
556 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid)
559 /* See if stealing the controlling tty back is necessary */
561 if (pgrp != getpid())
564 /* Use a temporary process to steal the controlling tty. */
565 if ((pid = fork()) < 0) {
566 message(LOG | CONSOLE, "\rCan't fork!\n");
571 ioctl(0, TIOCSCTTY, 1);
574 while((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
575 if (tmp_pid < 0 && errno == ECHILD)
581 /* Now fall though to actually execute things */
584 /* See if any special /bin/sh requiring characters are present */
585 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
588 strcat(strcpy(buf, "exec "), a->command);
592 /* Convert command (char*) into cmd (char**, one word per string) */
593 strcpy(buf, a->command);
595 for (tmpCmd = buf, i = 0;
596 (tmpCmd = strsep(&s, " \t")) != NULL;) {
597 if (*tmpCmd != '\0') {
608 Interactive shells want to see a dash in argv[0]. This
609 typically is handled by login, argv will be setup this
610 way if a dash appears at the front of the command path
614 if (*cmdpath == '-') {
616 /* skip over the dash */
619 /* find the last component in the command pathname */
620 s = get_last_path_component(cmdpath);
622 /* make a new argv[0] */
623 if ((cmd[0] = malloc(strlen(s)+2)) == NULL) {
624 message(LOG | CONSOLE, "malloc failed");
632 if (a->action & ASKFIRST) {
634 * Save memory by not exec-ing anything large (like a shell)
635 * before the user wants it. This is critical if swap is not
636 * enabled and the system has low memory. Generally this will
637 * be run on the second virtual console, and the first will
638 * be allowed to start a shell or whatever an init script
641 messageND(LOG, "Waiting for enter to start '%s' (pid %d, terminal %s)\n",
642 cmdpath, getpid(), a->terminal);
643 write(fileno(stdout), press_enter, sizeof(press_enter) - 1);
647 /* Log the process name and args */
648 messageND(LOG, "Starting pid %d, console %s: '%s'\n",
649 getpid(), a->terminal, cmdpath);
651 #if defined CONFIG_FEATURE_INIT_COREDUMPS
652 if (stat (CORE_ENABLE_FLAG_FILE, &sb) == 0) {
654 limit.rlim_cur = RLIM_INFINITY;
655 limit.rlim_max = RLIM_INFINITY;
656 setrlimit(RLIMIT_CORE, &limit);
660 /* Now run it. The new program will take over this PID,
661 * so nothing further in init.c should be run. */
662 execve(cmdpath, cmd, environment);
664 /* We're still here? Some error happened. */
665 message(LOG | CONSOLE, "\rBummer, could not run '%s': %s\n", cmdpath,
669 sigprocmask(SIG_SETMASK, &omask, NULL);
673 static int waitfor(struct init_action *a)
680 wpid = wait(&status);
681 if (wpid > 0 && wpid != pid) {
690 /* Run all commands of a particular type */
691 static void run_actions(int action)
693 struct init_action *a, *tmp;
695 for (a = init_action_list; a; a = tmp) {
697 if (a->action == action) {
698 if (a->action & (SYSINIT|WAIT|CTRLALTDEL|SHUTDOWN|RESTART)) {
700 delete_init_action(a);
701 } else if (a->action & ONCE) {
703 delete_init_action(a);
704 } else if (a->action & (RESPAWN|ASKFIRST)) {
705 /* Only run stuff with pid==0. If they have
706 * a pid, that means it is still running */
717 static void shutdown_system(void)
719 sigset_t block_signals;
721 /* first disable all our signals */
722 sigemptyset(&block_signals);
723 sigaddset(&block_signals, SIGHUP);
724 sigaddset(&block_signals, SIGCHLD);
725 sigaddset(&block_signals, SIGUSR1);
726 sigaddset(&block_signals, SIGUSR2);
727 sigaddset(&block_signals, SIGINT);
728 sigaddset(&block_signals, SIGTERM);
729 sigaddset(&block_signals, SIGCONT);
730 sigaddset(&block_signals, SIGSTOP);
731 sigaddset(&block_signals, SIGTSTP);
732 sigprocmask(SIG_BLOCK, &block_signals, NULL);
734 /* Allow Ctrl-Alt-Del to reboot system. */
735 init_reboot(RB_ENABLE_CAD);
737 message(CONSOLE|LOG, "\n\rThe system is going down NOW !!\n");
740 /* Send signals to every process _except_ pid 1 */
741 message(CONSOLE|LOG, "\rSending SIGTERM to all processes.\n");
746 message(CONSOLE|LOG, "\rSending SIGKILL to all processes.\n");
750 /* run everything to be run at "shutdown" */
751 run_actions(SHUTDOWN);
754 if (kernelVersion > 0 && kernelVersion <= KERNEL_VERSION(2,2,11)) {
755 /* bdflush, kupdate not needed for kernels >2.2.11 */
761 static void exec_signal(int sig)
763 struct init_action *a, *tmp;
764 sigset_t unblock_signals;
766 for (a = init_action_list; a; a = tmp) {
768 if (a->action & RESTART) {
771 /* unblock all signals, blocked in shutdown_system() */
772 sigemptyset(&unblock_signals);
773 sigaddset(&unblock_signals, SIGHUP);
774 sigaddset(&unblock_signals, SIGCHLD);
775 sigaddset(&unblock_signals, SIGUSR1);
776 sigaddset(&unblock_signals, SIGUSR2);
777 sigaddset(&unblock_signals, SIGINT);
778 sigaddset(&unblock_signals, SIGTERM);
779 sigaddset(&unblock_signals, SIGCONT);
780 sigaddset(&unblock_signals, SIGSTOP);
781 sigaddset(&unblock_signals, SIGTSTP);
782 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
784 message(CONSOLE|LOG, "\rTrying to re-exec %s\n", a->command);
785 execl(a->command, a->command, NULL);
787 message(CONSOLE|LOG, "\rexec of '%s' failed: %s\n",
788 a->command, sys_errlist[errno]);
791 init_reboot(RB_HALT_SYSTEM);
797 static void halt_signal(int sig)
802 /* Seems the s390 console is Wierd(tm). */
803 "\rThe system is halted. You may reboot now.\n"
805 /* secondConsole is NULL for a serial console */
806 "\rThe system is halted. Press %s or turn off power\n",
807 (secondConsole == NULL)? "Reset" : "CTRL-ALT-DEL"
812 /* allow time for last message to reach serial console */
815 if (sig == SIGUSR2 && kernelVersion >= KERNEL_VERSION(2,2,0))
816 init_reboot(RB_POWER_OFF);
818 init_reboot(RB_HALT_SYSTEM);
823 static void reboot_signal(int sig)
826 message(CONSOLE|LOG, "\rPlease stand by while rebooting the system.\n");
829 /* allow time for last message to reach serial console */
832 init_reboot(RB_AUTOBOOT);
837 static void ctrlaltdel_signal(int sig)
839 run_actions(CTRLALTDEL);
842 /* The SIGSTOP & SIGTSTP handler */
843 static void stop_handler(int sig)
845 int saved_errno = errno;
848 while(!got_cont) pause();
853 /* The SIGCONT handler */
854 static void cont_handler(int sig)
859 #endif /* ! DEBUG_INIT */
861 static void new_init_action(int action, char *command, char *cons)
863 struct init_action *new_action, *a;
868 /* If BusyBox detects that a serial console is in use, then entries
869 * not refering to the console or null devices will _not_ be run.
870 * The exception to this rule is the null device.
872 if (secondConsole == NULL && strcmp(cons, console)
873 && strcmp(cons, "/dev/null"))
875 if (strcmp(cons, "/dev/null") == 0 && (action & ASKFIRST))
878 new_action = calloc((size_t) (1), sizeof(struct init_action));
880 message(LOG | CONSOLE, "\rMemory allocation failure\n");
884 /* Append to the end of the list */
885 for (a = init_action_list; a && a->next; a = a->next) ;
887 a->next = new_action;
889 init_action_list = new_action;
891 strcpy(new_action->command, command);
892 new_action->action = action;
893 strcpy(new_action->terminal, cons);
895 // message(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
896 // new_action->command, new_action->action, new_action->terminal);
899 static void delete_init_action(struct init_action * action)
901 struct init_action *a, *b = NULL;
903 for (a = init_action_list; a; b = a, a = a->next) {
906 init_action_list = a->next;
916 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
917 * then parse_inittab() simply adds in some default
918 * actions(i.e., runs INIT_SCRIPT and then starts a pair
919 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
920 * _is_ defined, but /etc/inittab is missing, this
921 * results in the same set of default behaviors.
923 static void parse_inittab(void)
925 #ifdef CONFIG_FEATURE_USE_INITTAB
927 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE], tmpConsole[INIT_BUFFS_SIZE];
928 char *id, *runlev, *action, *command, *eol;
929 const struct init_action_type *a = actions;
933 file = fopen(INITTAB, "r");
935 /* No inittab file -- set up some default behavior */
937 /* Reboot on Ctrl-Alt-Del */
938 new_init_action(CTRLALTDEL, "/sbin/reboot", console);
939 /* Umount all filesystems on halt/reboot */
940 new_init_action(SHUTDOWN, "/bin/umount -a -r", console);
941 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
942 /* Swapoff on halt/reboot */
943 new_init_action(SHUTDOWN, "/sbin/swapoff -a", console);
945 /* Prepare to restart init when a HUP is received */
946 new_init_action(RESTART, "/sbin/init", console);
947 /* Askfirst shell on tty1 */
948 new_init_action(ASKFIRST, LOGIN_SHELL, console);
949 /* Askfirst shell on tty2 */
950 if (secondConsole != NULL)
951 new_init_action(ASKFIRST, LOGIN_SHELL, secondConsole);
952 /* Askfirst shell on tty3 */
953 if (thirdConsole != NULL)
954 new_init_action(ASKFIRST, LOGIN_SHELL, thirdConsole);
955 /* Askfirst shell on tty4 */
956 if (fourthConsole != NULL)
957 new_init_action(ASKFIRST, LOGIN_SHELL, fourthConsole);
959 new_init_action(SYSINIT, INIT_SCRIPT, console);
962 #ifdef CONFIG_FEATURE_USE_INITTAB
965 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
967 /* Skip leading spaces */
968 for (id = buf; *id == ' ' || *id == '\t'; id++);
970 /* Skip the line if it's a comment */
971 if (*id == '#' || *id == '\n')
974 /* Trim the trailing \n */
975 eol = strrchr(id, '\n');
979 /* Keep a copy around for posterity's sake (and error msgs) */
980 strcpy(lineAsRead, buf);
982 /* Separate the ID field from the runlevels */
983 runlev = strchr(id, ':');
984 if (runlev == NULL || *(runlev + 1) == '\0') {
985 message(LOG | CONSOLE, "\rBad inittab entry: %s\n", lineAsRead);
992 /* Separate the runlevels from the action */
993 action = strchr(runlev, ':');
994 if (action == NULL || *(action + 1) == '\0') {
995 message(LOG | CONSOLE, "\rBad inittab entry: %s\n", lineAsRead);
1002 /* Separate the action from the command */
1003 command = strchr(action, ':');
1004 if (command == NULL || *(command + 1) == '\0') {
1005 message(LOG | CONSOLE, "\rBad inittab entry: %s\n", lineAsRead);
1012 /* Ok, now process it */
1014 while (a->name != 0) {
1015 if (strcmp(a->name, action) == 0) {
1017 strcpy(tmpConsole, "/dev/");
1018 strncat(tmpConsole, id, INIT_BUFFS_SIZE-6);
1021 new_init_action(a->action, command, id);
1026 if (foundIt == TRUE)
1029 /* Choke on an unknown action */
1030 message(LOG | CONSOLE, "\rBad inittab entry: %s\n", lineAsRead);
1035 #endif /* CONFIG_FEATURE_USE_INITTAB */
1040 extern int init_main(int argc, char **argv)
1042 struct init_action *a;
1046 if (argc > 1 && !strcmp(argv[1], "-q")) {
1047 /* don't assume init's pid == 1 */
1048 long *pid = find_pid_by_name("init");
1049 if (!pid || *pid<=0) {
1050 pid = find_pid_by_name("linuxrc");
1051 if (!pid || *pid<=0)
1052 error_msg_and_die("no process killed");
1059 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1061 #ifdef CONFIG_FEATURE_INITRD
1062 && strstr(applet_name, "linuxrc") == NULL
1068 /* Set up sig handlers -- be sure to
1069 * clear all of these in run() */
1070 signal(SIGHUP, exec_signal);
1071 signal(SIGUSR1, halt_signal);
1072 signal(SIGUSR2, halt_signal);
1073 signal(SIGINT, ctrlaltdel_signal);
1074 signal(SIGTERM, reboot_signal);
1075 signal(SIGCONT, cont_handler);
1076 signal(SIGSTOP, stop_handler);
1077 signal(SIGTSTP, stop_handler);
1079 /* Turn off rebooting via CTL-ALT-DEL -- we get a
1080 * SIGINT on CAD so we can shut things down gracefully... */
1081 init_reboot(RB_DISABLE_CAD);
1084 /* Figure out what kernel this is running */
1085 kernelVersion = get_kernel_revision();
1087 /* Figure out where the default console should be */
1090 /* Close whatever files are open, and reset the console. */
1095 if(device_open(console, O_RDWR|O_NOCTTY)==0) {
1103 /* Make sure PATH is set to something sane */
1104 putenv("PATH="_PATH_STDPATH);
1107 message(MAYBE_CONSOLE|LOG, "\rinit started: %s\n", full_version);
1109 /* Make sure there is enough memory to do something useful. */
1112 /* Check if we are supposed to be in single user mode */
1113 if (argc > 1 && (!strcmp(argv[1], "single") ||
1114 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1115 /* Ask first then start a shell on tty2-4 */
1116 if (secondConsole != NULL)
1117 new_init_action(ASKFIRST, LOGIN_SHELL, secondConsole);
1118 if (thirdConsole != NULL)
1119 new_init_action(ASKFIRST, LOGIN_SHELL, thirdConsole);
1120 if (fourthConsole != NULL)
1121 new_init_action(ASKFIRST, LOGIN_SHELL, fourthConsole);
1122 /* Start a shell on tty1 */
1123 new_init_action(RESPAWN, LOGIN_SHELL, console);
1125 /* Not in single user mode -- see what inittab says */
1127 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1128 * then parse_inittab() simply adds in some default
1129 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1130 * of "askfirst" shells */
1134 /* Make the command line just say "init" -- thats all, nothing else */
1135 fixup_argv(argc, argv, "init");
1137 /* Now run everything that needs to be run */
1139 /* First run the sysinit command */
1140 run_actions(SYSINIT);
1142 /* Next run anything that wants to block */
1145 /* Next run anything to be run only once */
1148 /* If there is nothing else to do, stop */
1149 if (init_action_list == NULL) {
1150 message(LOG | CONSOLE, "\rNo more tasks for init -- sleeping forever.\n");
1154 /* Now run the looping stuff for the rest of forever */
1156 /* run the respawn stuff */
1157 run_actions(RESPAWN);
1159 /* run the askfirst stuff */
1160 run_actions(ASKFIRST);
1162 /* Don't consume all CPU time -- sleep a bit */
1165 /* Wait for a child process to exit */
1166 wpid = wait(&status);
1168 /* Find out who died and clean up their corpse */
1169 for (a = init_action_list; a; a = a->next) {
1170 if (a->pid == wpid) {
1171 /* Set the pid to 0 so that the process gets
1172 * restarted by run_actions() */
1174 message(LOG, "Process '%s' (pid %d) exited. "
1175 "Scheduling it for restart.\n", a->command, wpid);
1184 c-file-style: "linux"