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) 1999-2004 by Erik Andersen <andersen@codepoet.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/types.h>
44 #include <sys/reboot.h>
47 #include "init_shared.h"
51 # include <sys/syslog.h>
55 #define INIT_BUFFS_SIZE 256
57 /* From <linux/vt.h> */
59 unsigned short v_active; /* active vt */
60 unsigned short v_signal; /* signal to send */
61 unsigned short v_state; /* vt bitmask */
63 static const int VT_GETSTATE = 0x5603; /* get global vt state info */
65 /* From <linux/serial.h> */
66 struct serial_struct {
75 unsigned short close_delay;
77 char reserved_char[1];
79 unsigned short closing_wait; /* time to wait before closing */
80 unsigned short closing_wait2; /* no longer used... */
81 unsigned char *iomem_base;
82 unsigned short iomem_reg_shift;
83 unsigned int port_high;
84 unsigned long iomap_base; /* cookie passed into ioremap */
90 #define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
93 #if defined CONFIG_FEATURE_INIT_COREDUMPS
95 * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
96 * before processes are spawned to set core file size as unlimited.
97 * This is for debugging only. Don't use this is production, unless
98 * you want core dumps lying about....
100 #define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
101 #include <sys/resource.h>
102 #include <sys/time.h>
105 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
107 #define INITTAB "/etc/inittab" /* inittab file location */
109 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
112 #define MAXENV 16 /* Number of env. vars */
114 #define CONSOLE_BUFF_SIZE 32
116 /* Allowed init action types */
117 #define SYSINIT 0x001
118 #define RESPAWN 0x002
119 #define ASKFIRST 0x004
122 #define CTRLALTDEL 0x020
123 #define SHUTDOWN 0x040
124 #define RESTART 0x080
126 /* A mapping between "inittab" action name strings and action type codes. */
127 struct init_action_type {
132 static const struct init_action_type actions[] = {
133 {"sysinit", SYSINIT},
134 {"respawn", RESPAWN},
135 {"askfirst", ASKFIRST},
138 {"ctrlaltdel", CTRLALTDEL},
139 {"shutdown", SHUTDOWN},
140 {"restart", RESTART},
144 /* Set up a linked list of init_actions, to be read from inittab */
147 char command[INIT_BUFFS_SIZE];
148 char terminal[CONSOLE_BUFF_SIZE];
149 struct init_action *next;
153 /* Static variables */
154 static struct init_action *init_action_list = NULL;
155 static char console[CONSOLE_BUFF_SIZE] = _PATH_CONSOLE;
157 #ifndef CONFIG_SYSLOGD
158 static char *log_console = VC_5;
160 static sig_atomic_t got_cont = 0;
161 static const int LOG = 0x1;
162 static const int CONSOLE = 0x2;
164 #if defined CONFIG_FEATURE_EXTRA_QUIET
165 static const int MAYBE_CONSOLE = 0x0;
167 #define MAYBE_CONSOLE CONSOLE
169 #ifndef RB_HALT_SYSTEM
170 static const int RB_HALT_SYSTEM = 0xcdef0123;
171 static const int RB_ENABLE_CAD = 0x89abcdef;
172 static const int RB_DISABLE_CAD = 0;
174 #define RB_POWER_OFF 0x4321fedc
175 static const int RB_AUTOBOOT = 0x01234567;
178 static const char * const environment[] = {
180 "PATH=" _PATH_STDPATH,
186 /* Function prototypes */
187 static void delete_init_action(struct init_action *a);
188 static int waitfor(const struct init_action *a);
189 static void halt_signal(int sig);
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 void messageD(int device, const char *fmt, ...)
205 #define messageD message
207 static void message(int device, const char *fmt, ...)
208 __attribute__ ((format(printf, 2, 3)));
209 static void message(int device, const char *fmt, ...)
214 #ifndef CONFIG_SYSLOGD
215 static int log_fd = -1;
219 va_start(arguments, fmt);
220 l = vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments) + 1;
223 #ifdef CONFIG_SYSLOGD
224 /* Log the message to syslogd */
226 /* don`t out "\r\n" */
227 openlog(bb_applet_name, 0, LOG_DAEMON);
228 syslog(LOG_INFO, "%s", msg);
238 /* Take full control of the log tty, and never close it.
239 * It's mine, all mine! Muhahahaha! */
241 if ((log_fd = device_open(log_console, O_RDWR | O_NONBLOCK | O_NOCTTY)) < 0) {
243 bb_error_msg("Bummer, can't write to log on %s!", log_console);
246 fcntl(log_fd, F_SETFD, FD_CLOEXEC);
249 if ((device & LOG) && (log_fd >= 0)) {
250 bb_full_write(log_fd, msg, l);
254 if (device & CONSOLE) {
255 int fd = device_open(_PATH_CONSOLE,
256 O_WRONLY | O_NOCTTY | O_NONBLOCK);
257 /* Always send console messages to /dev/console so people will see them. */
259 bb_full_write(fd, msg, l);
262 /* all descriptors may be closed */
264 bb_error_msg("Bummer, can't print: ");
265 va_start(arguments, fmt);
266 vfprintf(stderr, fmt, arguments);
273 /* Set terminal settings to reasonable defaults */
274 static void set_term(int fd)
280 /* set control chars */
281 tty.c_cc[VINTR] = 3; /* C-c */
282 tty.c_cc[VQUIT] = 28; /* C-\ */
283 tty.c_cc[VERASE] = 127; /* C-? */
284 tty.c_cc[VKILL] = 21; /* C-u */
285 tty.c_cc[VEOF] = 4; /* C-d */
286 tty.c_cc[VSTART] = 17; /* C-q */
287 tty.c_cc[VSTOP] = 19; /* C-s */
288 tty.c_cc[VSUSP] = 26; /* C-z */
290 /* use line dicipline 0 */
293 /* Make it be sane */
294 tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
295 tty.c_cflag |= CREAD | HUPCL | CLOCAL;
299 tty.c_iflag = ICRNL | IXON | IXOFF;
302 tty.c_oflag = OPOST | ONLCR;
306 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
308 tcsetattr(fd, TCSANOW, &tty);
311 static void console_init(void)
316 struct serial_struct sr;
319 if ((s = getenv("CONSOLE")) != NULL || (s = getenv("console")) != NULL) {
320 safe_strncpy(console, s, sizeof(console));
322 /* sparc kernel supports console=tty[ab] parameter which is also
323 * passed to init, so catch it here */
324 /* remap tty[ab] to /dev/ttyS[01] */
325 if (strcmp(s, "ttya") == 0)
326 safe_strncpy(console, SC_0, sizeof(console));
327 else if (strcmp(s, "ttyb") == 0)
328 safe_strncpy(console, SC_1, sizeof(console));
331 /* 2.2 kernels: identify the real console backend and try to use it */
332 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
333 /* this is a serial console */
334 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
335 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
336 /* this is linux virtual tty */
337 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
339 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
344 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0 && tried < 2) {
345 /* Can't open selected console -- try
346 logical system console and VT_MASTER */
347 safe_strncpy(console, (tried == 0 ? _PATH_CONSOLE : CURRENT_VC),
352 /* Perhaps we should panic here? */
353 #ifndef CONFIG_SYSLOGD
356 safe_strncpy(console, "/dev/null", sizeof(console));
359 /* check for serial console */
360 if (ioctl(fd, TIOCGSERIAL, &sr) == 0) {
361 /* Force the TERM setting to vt102 for serial console --
362 * if TERM is set to linux (the default) */
363 if (s == NULL || strcmp(s, "linux") == 0)
364 putenv("TERM=vt102");
365 #ifndef CONFIG_SYSLOGD
366 log_console = console;
370 putenv("TERM=linux");
374 messageD(LOG, "console=%s", console);
377 static void fixup_argv(int argc, char **argv, char *new_argv0)
381 /* Fix up argv[0] to be certain we claim to be init */
382 len = strlen(argv[0]);
383 memset(argv[0], 0, len);
384 safe_strncpy(argv[0], new_argv0, len + 1);
386 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
389 memset(argv[len], 0, strlen(argv[len]));
394 static pid_t run(const struct init_action *a)
398 char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
399 char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
400 sigset_t nmask, omask;
401 static const char press_enter[] =
402 #ifdef CUSTOMIZED_BANNER
403 #include CUSTOMIZED_BANNER
405 "\nPlease press Enter to activate this console. ";
407 /* Block sigchild while forking. */
409 sigaddset(&nmask, SIGCHLD);
410 sigprocmask(SIG_BLOCK, &nmask, &omask);
412 if ((pid = fork()) == 0) {
419 sigprocmask(SIG_SETMASK, &omask, NULL);
421 /* Reset signal handlers that were set by the parent process */
422 signal(SIGUSR1, SIG_DFL);
423 signal(SIGUSR2, SIG_DFL);
424 signal(SIGINT, SIG_DFL);
425 signal(SIGTERM, SIG_DFL);
426 signal(SIGHUP, SIG_DFL);
427 signal(SIGQUIT, SIG_DFL);
428 signal(SIGCONT, SIG_DFL);
429 signal(SIGSTOP, SIG_DFL);
430 signal(SIGTSTP, SIG_DFL);
432 /* Create a new session and make ourself the process
436 /* Open the new terminal device */
437 if ((device_open(a->terminal, O_RDWR)) < 0) {
438 if (stat(a->terminal, &sb) != 0) {
439 message(LOG | CONSOLE, "device '%s' does not exist.", a->terminal);
441 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
446 /* Make sure the terminal will act fairly normal for us */
448 /* Setup stdout, stderr for the new process so
449 * they point to the supplied terminal */
453 /* If the init Action requires us to wait, then force the
454 * supplied terminal to be the controlling tty. */
455 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
458 /* Now fork off another process to just hang around */
459 if ((pid = fork()) < 0) {
460 message(LOG | CONSOLE, "Can't fork!");
466 /* We are the parent -- wait till the child is done */
467 signal(SIGINT, SIG_IGN);
468 signal(SIGTSTP, SIG_IGN);
469 signal(SIGQUIT, SIG_IGN);
470 signal(SIGCHLD, SIG_DFL);
472 /* Wait for child to exit */
473 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
474 if (tmp_pid == -1 && errno == ECHILD) {
477 /* FIXME handle other errors */
480 /* See if stealing the controlling tty back is necessary */
482 if (pgrp != getpid())
485 /* Use a temporary process to steal the controlling tty. */
486 if ((pid = fork()) < 0) {
487 message(LOG | CONSOLE, "Can't fork!");
492 ioctl(0, TIOCSCTTY, 1);
495 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
496 if (tmp_pid < 0 && errno == ECHILD)
502 /* Now fall though to actually execute things */
505 /* See if any special /bin/sh requiring characters are present */
506 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
507 cmd[0] = (char *)DEFAULT_SHELL;
509 cmd[2] = strcat(strcpy(buf, "exec "), a->command);
512 /* Convert command (char*) into cmd (char**, one word per string) */
513 strcpy(buf, a->command);
515 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
516 if (*tmpCmd != '\0') {
527 Interactive shells want to see a dash in argv[0]. This
528 typically is handled by login, argv will be setup this
529 way if a dash appears at the front of the command path
533 if (*cmdpath == '-') {
535 /* skip over the dash */
538 /* find the last component in the command pathname */
539 s = bb_get_last_path_component(cmdpath);
541 /* make a new argv[0] */
542 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
543 message(LOG | CONSOLE, bb_msg_memory_exhausted);
547 strcpy(cmd[0] + 1, s);
549 #ifdef CONFIG_FEATURE_INIT_SCTTY
550 /* Establish this process as session leader and
551 * (attempt) to make the tty (if any) a controlling tty.
554 (void) ioctl(0, TIOCSCTTY, 0/*don't steal it*/);
558 #if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
559 if (a->action & ASKFIRST) {
562 * Save memory by not exec-ing anything large (like a shell)
563 * before the user wants it. This is critical if swap is not
564 * enabled and the system has low memory. Generally this will
565 * be run on the second virtual console, and the first will
566 * be allowed to start a shell or whatever an init script
569 messageD(LOG, "Waiting for enter to start '%s'"
570 "(pid %d, terminal %s)\n",
571 cmdpath, getpid(), a->terminal);
572 bb_full_write(1, press_enter, sizeof(press_enter) - 1);
573 while(read(0, &c, 1) == 1 && c != '\n')
578 /* Log the process name and args */
579 message(LOG, "Starting pid %d, console %s: '%s'",
580 getpid(), a->terminal, cmdpath);
582 #if defined CONFIG_FEATURE_INIT_COREDUMPS
583 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
586 limit.rlim_cur = RLIM_INFINITY;
587 limit.rlim_max = RLIM_INFINITY;
588 setrlimit(RLIMIT_CORE, &limit);
592 /* Now run it. The new program will take over this PID,
593 * so nothing further in init.c should be run. */
596 /* We're still here? Some error happened. */
597 message(LOG | CONSOLE, "Bummer, could not run '%s': %m", cmdpath);
600 sigprocmask(SIG_SETMASK, &omask, NULL);
604 static int waitfor(const struct init_action *a)
611 wpid = waitpid(pid,&status,0);
614 if (wpid == -1 && errno == ECHILD) {
615 /* we missed its termination */
618 /* FIXME other errors should maybe trigger an error, but allow
619 * the program to continue */
624 /* Run all commands of a particular type */
625 static void run_actions(int action)
627 struct init_action *a, *tmp;
629 for (a = init_action_list; a; a = tmp) {
631 if (a->action == action) {
632 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
634 delete_init_action(a);
635 } else if (a->action & ONCE) {
637 delete_init_action(a);
638 } else if (a->action & (RESPAWN | ASKFIRST)) {
639 /* Only run stuff with pid==0. If they have
640 * a pid, that means it is still running */
650 static void init_reboot(unsigned long magic)
653 /* We have to fork here, since the kernel calls do_exit(0) in
654 * linux/kernel/sys.c, which can cause the machine to panic when
655 * the init process is killed.... */
656 if ((pid = fork()) == 0) {
660 waitpid (pid, NULL, 0);
663 static void shutdown_system(void)
665 sigset_t block_signals;
667 /* run everything to be run at "shutdown". This is done _prior_
668 * to killing everything, in case people wish to use scripts to
669 * shut things down gracefully... */
670 run_actions(SHUTDOWN);
672 /* first disable all our signals */
673 sigemptyset(&block_signals);
674 sigaddset(&block_signals, SIGHUP);
675 sigaddset(&block_signals, SIGQUIT);
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.");
705 static void exec_signal(int sig)
707 struct init_action *a, *tmp;
708 sigset_t unblock_signals;
710 for (a = init_action_list; a; a = tmp) {
712 if (a->action & RESTART) {
715 /* unblock all signals, blocked in shutdown_system() */
716 sigemptyset(&unblock_signals);
717 sigaddset(&unblock_signals, SIGHUP);
718 sigaddset(&unblock_signals, SIGQUIT);
719 sigaddset(&unblock_signals, SIGCHLD);
720 sigaddset(&unblock_signals, SIGUSR1);
721 sigaddset(&unblock_signals, SIGUSR2);
722 sigaddset(&unblock_signals, SIGINT);
723 sigaddset(&unblock_signals, SIGTERM);
724 sigaddset(&unblock_signals, SIGCONT);
725 sigaddset(&unblock_signals, SIGSTOP);
726 sigaddset(&unblock_signals, SIGTSTP);
727 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
729 /* Close whatever files are open. */
734 /* Open the new terminal device */
735 if ((device_open(a->terminal, O_RDWR)) < 0) {
737 if (stat(a->terminal, &sb) != 0) {
738 message(LOG | CONSOLE, "device '%s' does not exist.", a->terminal);
740 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
742 halt_signal(SIGUSR1);
745 /* Make sure the terminal will act fairly normal for us */
747 /* Setup stdout, stderr on the supplied terminal */
751 messageD(CONSOLE | LOG, "Trying to re-exec %s", a->command);
752 execl(a->command, a->command, NULL);
754 message(CONSOLE | LOG, "exec of '%s' failed: %m",
758 init_reboot(RB_HALT_SYSTEM);
764 static void halt_signal(int sig)
767 message(CONSOLE | LOG,
769 /* Seems the s390 console is Wierd(tm). */
770 "The system is halted. You may reboot now."
772 "The system is halted. Press Reset or turn off power"
777 /* allow time for last message to reach serial console */
781 init_reboot(RB_POWER_OFF);
783 init_reboot(RB_HALT_SYSTEM);
788 static void reboot_signal(int sig)
791 message(CONSOLE | LOG, "Please stand by while rebooting the system.");
794 /* allow time for last message to reach serial console */
797 init_reboot(RB_AUTOBOOT);
802 static void ctrlaltdel_signal(int sig)
804 run_actions(CTRLALTDEL);
807 /* The SIGSTOP & SIGTSTP handler */
808 static void stop_handler(int sig)
810 int saved_errno = errno;
819 /* The SIGCONT handler */
820 static void cont_handler(int sig)
825 #endif /* ! DEBUG_INIT */
827 static void new_init_action(int action, const char *command, const char *cons)
829 struct init_action *new_action, *a, *last;
834 /* do not run entries if console device is not available */
835 if (access(cons, R_OK | W_OK))
837 if (strcmp(cons, "/dev/null") == 0 && (action & ASKFIRST))
840 new_action = calloc((size_t) (1), sizeof(struct init_action));
842 message(LOG | CONSOLE, "Memory allocation failure");
846 /* Append to the end of the list */
847 for (a = last = init_action_list; a; a = a->next) {
848 /* don't enter action if it's already in the list,
849 * but do overwrite existing actions */
850 if ((strcmp(a->command, command) == 0) &&
851 (strcmp(a->terminal, cons) ==0)) {
859 last->next = new_action;
861 init_action_list = new_action;
863 strcpy(new_action->command, command);
864 new_action->action = action;
865 strcpy(new_action->terminal, cons);
866 #if 0 /* calloc zeroed always */
869 messageD(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
870 new_action->command, new_action->action, new_action->terminal);
873 static void delete_init_action(struct init_action *action)
875 struct init_action *a, *b = NULL;
877 for (a = init_action_list; a; b = a, a = a->next) {
880 init_action_list = a->next;
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 /* Swapoff on halt/reboot */
916 if(ENABLE_SWAPONOFF) new_init_action(SHUTDOWN, "/sbin/swapoff -a", "");
917 /* Prepare to restart init when a HUP is received */
918 new_init_action(RESTART, "/sbin/init", "");
919 /* Askfirst shell on tty1-4 */
920 new_init_action(ASKFIRST, bb_default_login_shell, "");
921 new_init_action(ASKFIRST, bb_default_login_shell, VC_2);
922 new_init_action(ASKFIRST, bb_default_login_shell, VC_3);
923 new_init_action(ASKFIRST, bb_default_login_shell, VC_4);
925 new_init_action(SYSINIT, INIT_SCRIPT, "");
928 #ifdef CONFIG_FEATURE_USE_INITTAB
931 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
932 /* Skip leading spaces */
933 for (id = buf; *id == ' ' || *id == '\t'; id++);
935 /* Skip the line if it's a comment */
936 if (*id == '#' || *id == '\n')
939 /* Trim the trailing \n */
940 eol = strrchr(id, '\n');
944 /* Keep a copy around for posterity's sake (and error msgs) */
945 strcpy(lineAsRead, buf);
947 /* Separate the ID field from the runlevels */
948 runlev = strchr(id, ':');
949 if (runlev == NULL || *(runlev + 1) == '\0') {
950 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
957 /* Separate the runlevels from the action */
958 action = strchr(runlev, ':');
959 if (action == NULL || *(action + 1) == '\0') {
960 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
967 /* Separate the action from the command */
968 command = strchr(action, ':');
969 if (command == NULL || *(command + 1) == '\0') {
970 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
977 /* Ok, now process it */
978 for (a = actions; a->name != 0; a++) {
979 if (strcmp(a->name, action) == 0) {
981 if(strncmp(id, "/dev/", 5) == 0)
983 strcpy(tmpConsole, "/dev/");
984 safe_strncpy(tmpConsole + 5, id,
985 CONSOLE_BUFF_SIZE - 5);
988 new_init_action(a->action, command, id);
993 /* Choke on an unknown action */
994 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
999 #endif /* CONFIG_FEATURE_USE_INITTAB */
1002 #ifdef CONFIG_FEATURE_USE_INITTAB
1003 static void reload_signal(int sig)
1005 struct init_action *a, *tmp;
1007 message(LOG, "Reloading /etc/inittab");
1009 /* disable old entrys */
1010 for (a = init_action_list; a; a = a->next ) {
1016 /* remove unused entrys */
1017 for (a = init_action_list; a; a = tmp) {
1019 if (a->action & (ONCE | SYSINIT | WAIT ) &&
1021 delete_init_action(a);
1024 run_actions(RESPAWN);
1027 #endif /* CONFIG_FEATURE_USE_INITTAB */
1029 extern int init_main(int argc, char **argv)
1031 struct init_action *a;
1035 if (argc > 1 && !strcmp(argv[1], "-q")) {
1036 return kill_init(SIGHUP);
1039 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1041 #ifdef CONFIG_FEATURE_INITRD
1042 && strstr(bb_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(SIGQUIT, exec_signal);
1051 signal(SIGUSR1, halt_signal);
1052 signal(SIGUSR2, halt_signal);
1053 signal(SIGINT, ctrlaltdel_signal);
1054 signal(SIGTERM, reboot_signal);
1055 signal(SIGCONT, cont_handler);
1056 signal(SIGSTOP, stop_handler);
1057 signal(SIGTSTP, stop_handler);
1059 /* Turn off rebooting via CTL-ALT-DEL -- we get a
1060 * SIGINT on CAD so we can shut things down gracefully... */
1061 init_reboot(RB_DISABLE_CAD);
1064 /* Figure out where the default console should be */
1067 /* Close whatever files are open, and reset the console. */
1072 if (device_open(console, O_RDWR | O_NOCTTY) == 0) {
1080 const char * const *e;
1081 /* Make sure environs is set to something sane */
1082 for(e = environment; *e; e++)
1083 putenv((char *) *e);
1086 message(MAYBE_CONSOLE | LOG, "init started: %s", bb_msg_full_version);
1088 /* Make sure there is enough memory to do something useful. */
1089 if (ENABLE_SWAPONOFF) {
1090 struct sysinfo info;
1092 if (!sysinfo(&info) &&
1093 (info.mem_unit ? : 1) * (long long)info.totalram < MEGABYTE)
1095 message(CONSOLE,"Low memory: forcing swapon.");
1096 /* swapon -a requires /proc typically */
1097 new_init_action(SYSINIT, "/bin/mount -t proc proc /proc", "");
1098 /* Try to turn on swap */
1099 new_init_action(SYSINIT, "/sbin/swapon -a", "");
1100 run_actions(SYSINIT); /* wait and removing */
1104 /* Check if we are supposed to be in single user mode */
1105 if (argc > 1 && (!strcmp(argv[1], "single") ||
1106 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1107 /* Start a shell on console */
1108 new_init_action(RESPAWN, bb_default_login_shell, "");
1110 /* Not in single user mode -- see what inittab says */
1112 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1113 * then parse_inittab() simply adds in some default
1114 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1115 * of "askfirst" shells */
1119 /* Make the command line just say "init" -- thats all, nothing else */
1120 fixup_argv(argc, argv, "init");
1122 /* Now run everything that needs to be run */
1124 /* First run the sysinit command */
1125 run_actions(SYSINIT);
1127 /* Next run anything that wants to block */
1130 /* Next run anything to be run only once */
1133 #ifdef CONFIG_FEATURE_USE_INITTAB
1134 /* Redefine SIGHUP to reread /etc/inittab */
1135 signal(SIGHUP, reload_signal);
1137 signal(SIGHUP, SIG_IGN);
1138 #endif /* CONFIG_FEATURE_USE_INITTAB */
1141 /* Now run the looping stuff for the rest of forever */
1143 /* run the respawn stuff */
1144 run_actions(RESPAWN);
1146 /* run the askfirst stuff */
1147 run_actions(ASKFIRST);
1149 /* Don't consume all CPU time -- sleep a bit */
1152 /* Wait for a child process to exit */
1153 wpid = wait(&status);
1155 /* Find out who died and clean up their corpse */
1156 for (a = init_action_list; a; a = a->next) {
1157 if (a->pid == wpid) {
1158 /* Set the pid to 0 so that the process gets
1159 * restarted by run_actions() */
1161 message(LOG, "Process '%s' (pid %d) exited. "
1162 "Scheduling it for restart.",
1166 /* see if anyone else is waiting to be reaped */
1167 wpid = waitpid (-1, &status, WNOHANG);
1174 c-file-style: "linux"