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 #define CONSOLE_BUFF_SIZE 32
125 /* Allowed init action types */
126 #define SYSINIT 0x001
127 #define RESPAWN 0x002
128 #define ASKFIRST 0x004
131 #define CTRLALTDEL 0x020
132 #define SHUTDOWN 0x040
133 #define RESTART 0x080
135 /* A mapping between "inittab" action name strings and action type codes. */
136 struct init_action_type {
141 static const struct init_action_type actions[] = {
142 {"sysinit", SYSINIT},
143 {"respawn", RESPAWN},
144 {"askfirst", ASKFIRST},
147 {"ctrlaltdel", CTRLALTDEL},
148 {"shutdown", SHUTDOWN},
149 {"restart", RESTART},
153 /* Set up a linked list of init_actions, to be read from inittab */
156 char command[INIT_BUFFS_SIZE];
157 char terminal[CONSOLE_BUFF_SIZE];
158 struct init_action *next;
162 /* Static variables */
163 static struct init_action *init_action_list = NULL;
164 static int kernelVersion;
165 static char console[CONSOLE_BUFF_SIZE] = _PATH_CONSOLE;
167 #ifndef CONFIG_SYSLOGD
168 static char *log = VC_5;
170 static sig_atomic_t got_cont = 0;
171 static const int LOG = 0x1;
172 static const int CONSOLE = 0x2;
174 #if defined CONFIG_FEATURE_EXTRA_QUIET
175 static const int MAYBE_CONSOLE = 0x0;
177 #define MAYBE_CONSOLE CONSOLE
179 #ifndef RB_HALT_SYSTEM
180 static const int RB_HALT_SYSTEM = 0xcdef0123;
181 static const int RB_ENABLE_CAD = 0x89abcdef;
182 static const int RB_DISABLE_CAD = 0;
184 #define RB_POWER_OFF 0x4321fedc
185 static const int RB_AUTOBOOT = 0x01234567;
188 static const char * const environment[] = {
190 "PATH=" _PATH_STDPATH,
196 /* Function prototypes */
197 static void delete_init_action(struct init_action *a);
198 static int waitfor(const struct init_action *a);
201 static void loop_forever(void)
207 /* Print a message to the specified device.
208 * Device may be bitwise-or'd from LOG | CONSOLE */
210 static inline void messageD(int device, const char *fmt, ...)
214 #define messageD message
216 static void message(int device, const char *fmt, ...)
217 __attribute__ ((format(printf, 2, 3)));
218 static void message(int device, const char *fmt, ...)
225 va_start(arguments, fmt);
226 l = vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments) + 1;
229 #ifdef CONFIG_SYSLOGD
230 /* Log the message to syslogd */
232 /* don`t out "\r\n" */
233 syslog_msg(LOG_DAEMON, LOG_INFO, msg + 1);
239 static int log_fd = -1;
243 /* Take full control of the log tty, and never close it.
244 * It's mine, all mine! Muhahahaha! */
246 if ((log_fd = device_open(log, O_RDWR | O_NDELAY | O_NOCTTY)) < 0) {
248 error_msg("Bummer, can't write to log on %s!", log);
251 fcntl(log_fd, F_SETFD, FD_CLOEXEC);
254 if ((device & LOG) && (log_fd >= 0)) {
255 full_write(log_fd, msg, l);
259 if (device & CONSOLE) {
260 int fd = device_open(_PATH_CONSOLE,
261 O_WRONLY | O_NOCTTY | O_NDELAY);
262 /* Always send console messages to /dev/console so people will see them. */
264 full_write(fd, msg, l);
267 /* all descriptors may be closed */
269 error_msg("Bummer, can't print: ");
270 va_start(arguments, fmt);
271 vfprintf(stderr, fmt, arguments);
278 /* Set terminal settings to reasonable defaults */
279 static void set_term(int fd)
285 /* set control chars */
286 tty.c_cc[VINTR] = 3; /* C-c */
287 tty.c_cc[VQUIT] = 28; /* C-\ */
288 tty.c_cc[VERASE] = 127; /* C-? */
289 tty.c_cc[VKILL] = 21; /* C-u */
290 tty.c_cc[VEOF] = 4; /* C-d */
291 tty.c_cc[VSTART] = 17; /* C-q */
292 tty.c_cc[VSTOP] = 19; /* C-s */
293 tty.c_cc[VSUSP] = 26; /* C-z */
295 /* use line dicipline 0 */
298 /* Make it be sane */
299 tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
300 tty.c_cflag |= CREAD | HUPCL | CLOCAL;
304 tty.c_iflag = ICRNL | IXON | IXOFF;
307 tty.c_oflag = OPOST | ONLCR;
311 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
313 tcsetattr(fd, TCSANOW, &tty);
316 /* How much memory does this machine have?
317 Units are kBytes to avoid overflow on 4GB machines */
318 static int check_free_memory(void)
321 unsigned int result, u, s = 10;
323 if (sysinfo(&info) != 0) {
324 perror_msg("Error checking free memory");
328 /* Kernels 2.0.x and 2.2.x return info.mem_unit==0 with values in bytes.
329 * Kernels 2.4.0 return info.mem_unit in bytes. */
333 while ((u & 1) == 0 && s > 0) {
337 result = (info.totalram >> s) + (info.totalswap >> s);
344 static void console_init(void)
349 struct serial_struct sr;
352 if ((s = getenv("CONSOLE")) != NULL || (s = getenv("console")) != NULL) {
353 safe_strncpy(console, s, sizeof(console));
355 /* sparc kernel supports console=tty[ab] parameter which is also
356 * passed to init, so catch it here */
357 /* remap tty[ab] to /dev/ttyS[01] */
358 if (strcmp(s, "ttya") == 0)
359 safe_strncpy(console, SC_0, sizeof(console));
360 else if (strcmp(s, "ttyb") == 0)
361 safe_strncpy(console, SC_1, sizeof(console));
364 /* 2.2 kernels: identify the real console backend and try to use it */
365 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
366 /* this is a serial console */
367 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
368 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
369 /* this is linux virtual tty */
370 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
372 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
377 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0 && tried < 2) {
378 /* Can't open selected console -- try
379 logical system console and VT_MASTER */
380 safe_strncpy(console, (tried == 0 ? _PATH_CONSOLE : CURRENT_VC),
385 /* Perhaps we should panic here? */
386 #ifndef CONFIG_SYSLOGD
389 safe_strncpy(console, "/dev/null", sizeof(console));
392 /* check for serial console */
393 if (ioctl(fd, TIOCGSERIAL, &sr) == 0) {
394 /* Force the TERM setting to vt102 for serial console --
395 * if TERM is set to linux (the default) */
396 if (s == NULL || strcmp(s, "linux") == 0)
397 putenv("TERM=vt102");
398 #ifndef CONFIG_SYSLOGD
403 putenv("TERM=linux");
407 messageD(LOG, "console=%s", console);
410 static void fixup_argv(int argc, char **argv, char *new_argv0)
414 /* Fix up argv[0] to be certain we claim to be init */
415 len = strlen(argv[0]);
416 memset(argv[0], 0, len);
417 safe_strncpy(argv[0], new_argv0, len + 1);
419 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
422 memset(argv[len], 0, strlen(argv[len]));
427 static pid_t run(const struct init_action *a)
431 pid_t pid, pgrp, tmp_pid;
432 char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
433 char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
434 sigset_t nmask, omask;
435 static const char press_enter[] =
436 #ifdef CUSTOMIZED_BANNER
437 #include CUSTOMIZED_BANNER
439 "\nPlease press Enter to activate this console. ";
441 /* Block sigchild while forking. */
443 sigaddset(&nmask, SIGCHLD);
444 sigprocmask(SIG_BLOCK, &nmask, &omask);
446 if ((pid = fork()) == 0) {
451 sigprocmask(SIG_SETMASK, &omask, NULL);
453 /* Reset signal handlers that were set by the parent process */
454 signal(SIGUSR1, SIG_DFL);
455 signal(SIGUSR2, SIG_DFL);
456 signal(SIGINT, SIG_DFL);
457 signal(SIGTERM, SIG_DFL);
458 signal(SIGHUP, SIG_DFL);
459 signal(SIGCONT, SIG_DFL);
460 signal(SIGSTOP, SIG_DFL);
461 signal(SIGTSTP, SIG_DFL);
463 /* Create a new session and make ourself the process
467 /* Open the new terminal device */
468 if ((device_open(a->terminal, O_RDWR)) < 0) {
469 if (stat(a->terminal, &sb) != 0) {
470 message(LOG | CONSOLE, "device '%s' does not exist.",
474 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
478 /* Make sure the terminal will act fairly normal for us */
480 /* Setup stdout, stderr for the new process so
481 * they point to the supplied terminal */
485 /* If the init Action requires us to wait, then force the
486 * supplied terminal to be the controlling tty. */
487 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
489 /* Now fork off another process to just hang around */
490 if ((pid = fork()) < 0) {
491 message(LOG | CONSOLE, "Can't fork!");
497 /* We are the parent -- wait till the child is done */
498 signal(SIGINT, SIG_IGN);
499 signal(SIGTSTP, SIG_IGN);
500 signal(SIGQUIT, SIG_IGN);
501 signal(SIGCHLD, SIG_DFL);
503 /* Wait for child to exit */
504 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid);
506 /* See if stealing the controlling tty back is necessary */
508 if (pgrp != getpid())
511 /* Use a temporary process to steal the controlling tty. */
512 if ((pid = fork()) < 0) {
513 message(LOG | CONSOLE, "Can't fork!");
518 ioctl(0, TIOCSCTTY, 1);
521 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
522 if (tmp_pid < 0 && errno == ECHILD)
528 /* Now fall though to actually execute things */
531 /* See if any special /bin/sh requiring characters are present */
532 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
535 cmd[2] = strcat(strcpy(buf, "exec "), a->command);
538 /* Convert command (char*) into cmd (char**, one word per string) */
539 strcpy(buf, a->command);
541 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
542 if (*tmpCmd != '\0') {
553 Interactive shells want to see a dash in argv[0]. This
554 typically is handled by login, argv will be setup this
555 way if a dash appears at the front of the command path
559 if (*cmdpath == '-') {
561 /* skip over the dash */
564 /* find the last component in the command pathname */
565 s = get_last_path_component(cmdpath);
567 /* make a new argv[0] */
568 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
569 message(LOG | CONSOLE, memory_exhausted);
573 strcpy(cmd[0] + 1, s);
577 if (a->action & ASKFIRST) {
580 * Save memory by not exec-ing anything large (like a shell)
581 * before the user wants it. This is critical if swap is not
582 * enabled and the system has low memory. Generally this will
583 * be run on the second virtual console, and the first will
584 * be allowed to start a shell or whatever an init script
587 messageD(LOG, "Waiting for enter to start '%s'"
588 "(pid %d, terminal %s)\n",
589 cmdpath, getpid(), a->terminal);
590 full_write(1, press_enter, sizeof(press_enter) - 1);
591 while(read(0, &c, 1) == 1 && c != '\n')
595 /* Log the process name and args */
596 message(LOG, "Starting pid %d, console %s: '%s'",
597 getpid(), a->terminal, cmdpath);
599 #if defined CONFIG_FEATURE_INIT_COREDUMPS
600 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
603 limit.rlim_cur = RLIM_INFINITY;
604 limit.rlim_max = RLIM_INFINITY;
605 setrlimit(RLIMIT_CORE, &limit);
609 /* Now run it. The new program will take over this PID,
610 * so nothing further in init.c should be run. */
613 /* We're still here? Some error happened. */
614 message(LOG | CONSOLE, "Bummer, could not run '%s': %m", cmdpath);
617 sigprocmask(SIG_SETMASK, &omask, NULL);
621 static int waitfor(const struct init_action *a)
628 wpid = wait(&status);
629 if (wpid > 0 && wpid != pid) {
638 /* Run all commands of a particular type */
639 static void run_actions(int action)
641 struct init_action *a, *tmp;
643 for (a = init_action_list; a; a = tmp) {
645 if (a->action == action) {
646 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
648 delete_init_action(a);
649 } else if (a->action & ONCE) {
651 delete_init_action(a);
652 } else if (a->action & (RESPAWN | ASKFIRST)) {
653 /* Only run stuff with pid==0. If they have
654 * a pid, that means it is still running */
664 static void shutdown_system(void)
666 sigset_t block_signals;
668 /* run everything to be run at "shutdown". This is done _prior_
669 * to killing everything, in case people wish to use scripts to
670 * shut things down gracefully... */
671 run_actions(SHUTDOWN);
673 /* first disable all our signals */
674 sigemptyset(&block_signals);
675 sigaddset(&block_signals, SIGHUP);
676 sigaddset(&block_signals, SIGCHLD);
677 sigaddset(&block_signals, SIGUSR1);
678 sigaddset(&block_signals, SIGUSR2);
679 sigaddset(&block_signals, SIGINT);
680 sigaddset(&block_signals, SIGTERM);
681 sigaddset(&block_signals, SIGCONT);
682 sigaddset(&block_signals, SIGSTOP);
683 sigaddset(&block_signals, SIGTSTP);
684 sigprocmask(SIG_BLOCK, &block_signals, NULL);
686 /* Allow Ctrl-Alt-Del to reboot system. */
687 init_reboot(RB_ENABLE_CAD);
689 message(CONSOLE | LOG, "The system is going down NOW !!");
692 /* Send signals to every process _except_ pid 1 */
693 message(CONSOLE | LOG, "Sending SIGTERM to all processes.");
698 message(CONSOLE | LOG, "Sending SIGKILL to all processes.");
703 if (kernelVersion > 0 && kernelVersion <= KERNEL_VERSION(2, 2, 11)) {
704 /* bdflush, kupdate not needed for kernels >2.2.11 */
710 static void exec_signal(int sig)
712 struct init_action *a, *tmp;
713 sigset_t unblock_signals;
715 for (a = init_action_list; a; a = tmp) {
717 if (a->action & RESTART) {
720 /* unblock all signals, blocked in shutdown_system() */
721 sigemptyset(&unblock_signals);
722 sigaddset(&unblock_signals, SIGHUP);
723 sigaddset(&unblock_signals, SIGCHLD);
724 sigaddset(&unblock_signals, SIGUSR1);
725 sigaddset(&unblock_signals, SIGUSR2);
726 sigaddset(&unblock_signals, SIGINT);
727 sigaddset(&unblock_signals, SIGTERM);
728 sigaddset(&unblock_signals, SIGCONT);
729 sigaddset(&unblock_signals, SIGSTOP);
730 sigaddset(&unblock_signals, SIGTSTP);
731 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
733 messageD(CONSOLE | LOG, "Trying to re-exec %s", a->command);
734 execl(a->command, a->command, NULL);
736 message(CONSOLE | LOG, "exec of '%s' failed: %m",
740 init_reboot(RB_HALT_SYSTEM);
746 static void halt_signal(int sig)
749 message(CONSOLE | LOG,
751 /* Seems the s390 console is Wierd(tm). */
752 "The system is halted. You may reboot now."
754 "The system is halted. Press Reset or turn off power"
759 /* allow time for last message to reach serial console */
762 if (sig == SIGUSR2 && kernelVersion >= KERNEL_VERSION(2, 2, 0))
763 init_reboot(RB_POWER_OFF);
765 init_reboot(RB_HALT_SYSTEM);
770 static void reboot_signal(int sig)
773 message(CONSOLE | LOG, "Please stand by while rebooting the system.");
776 /* allow time for last message to reach serial console */
779 init_reboot(RB_AUTOBOOT);
784 static void ctrlaltdel_signal(int sig)
786 run_actions(CTRLALTDEL);
789 /* The SIGSTOP & SIGTSTP handler */
790 static void stop_handler(int sig)
792 int saved_errno = errno;
801 /* The SIGCONT handler */
802 static void cont_handler(int sig)
807 #endif /* ! DEBUG_INIT */
809 static void new_init_action(int action, char *command, const char *cons)
811 struct init_action *new_action, *a;
816 /* do not run entries if console device is not available */
817 if (access(cons, R_OK | W_OK))
819 if (strcmp(cons, "/dev/null") == 0 && (action & ASKFIRST))
822 new_action = calloc((size_t) (1), sizeof(struct init_action));
824 message(LOG | CONSOLE, "Memory allocation failure");
828 /* Append to the end of the list */
829 for (a = init_action_list; a && a->next; a = a->next);
831 a->next = new_action;
833 init_action_list = new_action;
835 strcpy(new_action->command, command);
836 new_action->action = action;
837 strcpy(new_action->terminal, cons);
838 #if 0 /* calloc zeroed always */
841 messageD(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
842 new_action->command, new_action->action, new_action->terminal);
845 static void delete_init_action(struct init_action *action)
847 struct init_action *a, *b = NULL;
849 for (a = init_action_list; a; b = a, a = a->next) {
852 init_action_list = a->next;
862 /* Make sure there is enough memory to do something useful. *
863 * Calls "swapon -a" if needed so be sure /etc/fstab is present... */
864 static void check_memory(void)
868 if (check_free_memory() > 1000)
871 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
872 if (stat("/etc/fstab", &statBuf) == 0) {
873 /* swapon -a requires /proc typically */
874 new_init_action(SYSINIT, "/bin/mount -t proc proc /proc", "");
875 /* Try to turn on swap */
876 new_init_action(SYSINIT, "/sbin/swapon -a", "");
877 run_actions(SYSINIT); /* wait and removing */
878 if (check_free_memory() < 1000)
886 message(CONSOLE, "Sorry, your computer does not have enough memory.");
890 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
891 * then parse_inittab() simply adds in some default
892 * actions(i.e., runs INIT_SCRIPT and then starts a pair
893 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
894 * _is_ defined, but /etc/inittab is missing, this
895 * results in the same set of default behaviors.
897 static void parse_inittab(void)
899 #ifdef CONFIG_FEATURE_USE_INITTAB
901 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
902 char tmpConsole[CONSOLE_BUFF_SIZE];
903 char *id, *runlev, *action, *command, *eol;
904 const struct init_action_type *a = actions;
907 file = fopen(INITTAB, "r");
909 /* No inittab file -- set up some default behavior */
911 /* Reboot on Ctrl-Alt-Del */
912 new_init_action(CTRLALTDEL, "/sbin/reboot", "");
913 /* Umount all filesystems on halt/reboot */
914 new_init_action(SHUTDOWN, "/bin/umount -a -r", "");
915 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
916 /* Swapoff on halt/reboot */
917 new_init_action(SHUTDOWN, "/sbin/swapoff -a", "");
919 /* Prepare to restart init when a HUP is received */
920 new_init_action(RESTART, "/sbin/init", "");
921 /* Askfirst shell on tty1-4 */
922 new_init_action(ASKFIRST, LOGIN_SHELL, "");
923 new_init_action(ASKFIRST, LOGIN_SHELL, VC_2);
924 new_init_action(ASKFIRST, LOGIN_SHELL, VC_3);
925 new_init_action(ASKFIRST, LOGIN_SHELL, VC_4);
927 new_init_action(SYSINIT, INIT_SCRIPT, "");
930 #ifdef CONFIG_FEATURE_USE_INITTAB
933 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
934 /* Skip leading spaces */
935 for (id = buf; *id == ' ' || *id == '\t'; id++);
937 /* Skip the line if it's a comment */
938 if (*id == '#' || *id == '\n')
941 /* Trim the trailing \n */
942 eol = strrchr(id, '\n');
946 /* Keep a copy around for posterity's sake (and error msgs) */
947 strcpy(lineAsRead, buf);
949 /* Separate the ID field from the runlevels */
950 runlev = strchr(id, ':');
951 if (runlev == NULL || *(runlev + 1) == '\0') {
952 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
959 /* Separate the runlevels from the action */
960 action = strchr(runlev, ':');
961 if (action == NULL || *(action + 1) == '\0') {
962 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
969 /* Separate the action from the command */
970 command = strchr(action, ':');
971 if (command == NULL || *(command + 1) == '\0') {
972 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
979 /* Ok, now process it */
980 for (a = actions; a->name != 0; a++) {
981 if (strcmp(a->name, action) == 0) {
983 if(strncmp(id, "/dev/", 5) == 0)
985 strcpy(tmpConsole, "/dev/");
986 safe_strncpy(tmpConsole + 5, id,
987 CONSOLE_BUFF_SIZE - 5);
990 new_init_action(a->action, command, id);
995 /* Choke on an unknown action */
996 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1001 #endif /* CONFIG_FEATURE_USE_INITTAB */
1005 extern int init_main(int argc, char **argv)
1007 struct init_action *a;
1011 if (argc > 1 && !strcmp(argv[1], "-q")) {
1012 /* don't assume init's pid == 1 */
1013 long *pid = find_pid_by_name("init");
1015 if (!pid || *pid <= 0) {
1016 pid = find_pid_by_name("linuxrc");
1017 if (!pid || *pid <= 0)
1018 error_msg_and_die("no process killed");
1020 return kill(*pid, SIGHUP);
1023 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1025 #ifdef CONFIG_FEATURE_INITRD
1026 && strstr(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 what kernel this is running */
1048 kernelVersion = get_kernel_revision();
1050 /* Figure out where the default console should be */
1053 /* Close whatever files are open, and reset the console. */
1058 if (device_open(console, O_RDWR | O_NOCTTY) == 0) {
1066 const char * const *e;
1067 /* Make sure environs is set to something sane */
1068 for(e = environment; *e; e++)
1072 message(MAYBE_CONSOLE | LOG, "init started: %s", full_version);
1074 /* Make sure there is enough memory to do something useful. */
1077 /* Check if we are supposed to be in single user mode */
1078 if (argc > 1 && (!strcmp(argv[1], "single") ||
1079 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1080 /* Start a shell on console */
1081 new_init_action(RESPAWN, LOGIN_SHELL, "");
1083 /* Not in single user mode -- see what inittab says */
1085 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1086 * then parse_inittab() simply adds in some default
1087 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1088 * of "askfirst" shells */
1092 /* Make the command line just say "init" -- thats all, nothing else */
1093 fixup_argv(argc, argv, "init");
1095 /* Now run everything that needs to be run */
1097 /* First run the sysinit command */
1098 run_actions(SYSINIT);
1100 /* Next run anything that wants to block */
1103 /* Next run anything to be run only once */
1106 /* If there is nothing else to do, stop */
1107 if (init_action_list == NULL) {
1108 message(LOG | CONSOLE,
1109 "No more tasks for init -- sleeping forever.");
1113 /* Now run the looping stuff for the rest of forever */
1115 /* run the respawn stuff */
1116 run_actions(RESPAWN);
1118 /* run the askfirst stuff */
1119 run_actions(ASKFIRST);
1121 /* Don't consume all CPU time -- sleep a bit */
1124 /* Wait for a child process to exit */
1125 wpid = wait(&status);
1127 /* Find out who died and clean up their corpse */
1128 for (a = init_action_list; a; a = a->next) {
1129 if (a->pid == wpid) {
1130 /* Set the pid to 0 so that the process gets
1131 * restarted by run_actions() */
1133 message(LOG, "Process '%s' (pid %d) exited. "
1134 "Scheduling it for restart.",
1138 /* see if anyone else is waiting to be reaped */
1139 wpid = waitpid (-1, &status, WNOHANG);
1146 c-file-style: "linux"