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 "init_shared.h"
51 # include <sys/syslog.h>
53 #if (__GNU_LIBRARY__ > 5) || defined(__dietlibc__)
54 #include <sys/reboot.h>
58 #if defined(__UCLIBC__) && !defined(__UCLIBC_HAS_MMU__)
62 #define INIT_BUFFS_SIZE 256
64 /* From <linux/vt.h> */
66 unsigned short v_active; /* active vt */
67 unsigned short v_signal; /* signal to send */
68 unsigned short v_state; /* vt bitmask */
70 static const int VT_GETSTATE = 0x5603; /* get global vt state info */
72 /* From <linux/serial.h> */
73 struct serial_struct {
82 unsigned short close_delay;
83 char reserved_char[2];
85 unsigned short closing_wait; /* time to wait before closing */
86 unsigned short closing_wait2; /* no longer used... */
92 #define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
95 #if defined CONFIG_FEATURE_INIT_COREDUMPS
97 * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
98 * before processes are spawned to set core file size as unlimited.
99 * This is for debugging only. Don't use this is production, unless
100 * you want core dumps lying about....
102 #define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
103 #include <sys/resource.h>
104 #include <sys/time.h>
107 #define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
109 #define SHELL "/bin/sh" /* Default shell */
110 #define LOGIN_SHELL "-" SHELL /* Default login shell */
111 #define INITTAB "/etc/inittab" /* inittab file location */
113 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
116 #define MAXENV 16 /* Number of env. vars */
118 #define CONSOLE_BUFF_SIZE 32
120 /* Allowed init action types */
121 #define SYSINIT 0x001
122 #define RESPAWN 0x002
123 #define ASKFIRST 0x004
126 #define CTRLALTDEL 0x020
127 #define SHUTDOWN 0x040
128 #define RESTART 0x080
130 /* A mapping between "inittab" action name strings and action type codes. */
131 struct init_action_type {
136 static const struct init_action_type actions[] = {
137 {"sysinit", SYSINIT},
138 {"respawn", RESPAWN},
139 {"askfirst", ASKFIRST},
142 {"ctrlaltdel", CTRLALTDEL},
143 {"shutdown", SHUTDOWN},
144 {"restart", RESTART},
148 /* Set up a linked list of init_actions, to be read from inittab */
151 char command[INIT_BUFFS_SIZE];
152 char terminal[CONSOLE_BUFF_SIZE];
153 struct init_action *next;
157 /* Static variables */
158 static struct init_action *init_action_list = NULL;
159 static char console[CONSOLE_BUFF_SIZE] = _PATH_CONSOLE;
161 #ifndef CONFIG_SYSLOGD
162 static char *log = VC_5;
164 static sig_atomic_t got_cont = 0;
165 static const int LOG = 0x1;
166 static const int CONSOLE = 0x2;
168 #if defined CONFIG_FEATURE_EXTRA_QUIET
169 static const int MAYBE_CONSOLE = 0x0;
171 #define MAYBE_CONSOLE CONSOLE
173 #ifndef RB_HALT_SYSTEM
174 static const int RB_HALT_SYSTEM = 0xcdef0123;
175 static const int RB_ENABLE_CAD = 0x89abcdef;
176 static const int RB_DISABLE_CAD = 0;
178 #define RB_POWER_OFF 0x4321fedc
179 static const int RB_AUTOBOOT = 0x01234567;
182 static const char * const environment[] = {
184 "PATH=" _PATH_STDPATH,
190 /* Function prototypes */
191 static void delete_init_action(struct init_action *a);
192 static int waitfor(const struct init_action *a);
193 static void halt_signal(int sig);
196 static void loop_forever(void)
202 /* Print a message to the specified device.
203 * Device may be bitwise-or'd from LOG | CONSOLE */
205 static inline void messageD(int device, const char *fmt, ...)
209 #define messageD message
211 static void message(int device, const char *fmt, ...)
212 __attribute__ ((format(printf, 2, 3)));
213 static void message(int device, const char *fmt, ...)
218 #ifndef CONFIG_SYSLOGD
219 static int log_fd = -1;
223 va_start(arguments, fmt);
224 l = vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments) + 1;
227 #ifdef CONFIG_SYSLOGD
228 /* Log the message to syslogd */
230 /* don`t out "\r\n" */
231 syslog_msg(LOG_DAEMON, LOG_INFO, msg + 1);
240 /* Take full control of the log tty, and never close it.
241 * It's mine, all mine! Muhahahaha! */
243 if ((log_fd = device_open(log, O_RDWR | O_NDELAY | O_NOCTTY)) < 0) {
245 bb_error_msg("Bummer, can't write to log on %s!", log);
248 fcntl(log_fd, F_SETFD, FD_CLOEXEC);
251 if ((device & LOG) && (log_fd >= 0)) {
252 bb_full_write(log_fd, msg, l);
256 if (device & CONSOLE) {
257 int fd = device_open(_PATH_CONSOLE,
258 O_WRONLY | O_NOCTTY | O_NDELAY);
259 /* Always send console messages to /dev/console so people will see them. */
261 bb_full_write(fd, msg, l);
264 /* all descriptors may be closed */
266 bb_error_msg("Bummer, can't print: ");
267 va_start(arguments, fmt);
268 vfprintf(stderr, fmt, arguments);
275 /* Set terminal settings to reasonable defaults */
276 static void set_term(int fd)
282 /* set control chars */
283 tty.c_cc[VINTR] = 3; /* C-c */
284 tty.c_cc[VQUIT] = 28; /* C-\ */
285 tty.c_cc[VERASE] = 127; /* C-? */
286 tty.c_cc[VKILL] = 21; /* C-u */
287 tty.c_cc[VEOF] = 4; /* C-d */
288 tty.c_cc[VSTART] = 17; /* C-q */
289 tty.c_cc[VSTOP] = 19; /* C-s */
290 tty.c_cc[VSUSP] = 26; /* C-z */
292 /* use line dicipline 0 */
295 /* Make it be sane */
296 tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
297 tty.c_cflag |= CREAD | HUPCL | CLOCAL;
301 tty.c_iflag = ICRNL | IXON | IXOFF;
304 tty.c_oflag = OPOST | ONLCR;
308 ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
310 tcsetattr(fd, TCSANOW, &tty);
313 /* How much memory does this machine have?
314 Units are kBytes to avoid overflow on 4GB machines */
315 static int check_free_memory(void)
318 unsigned int result, u, s = 10;
320 if (sysinfo(&info) != 0) {
321 bb_perror_msg("Error checking free memory");
325 /* Kernels 2.0.x and 2.2.x return info.mem_unit==0 with values in bytes.
326 * Kernels 2.4.0 return info.mem_unit in bytes. */
330 while ((u & 1) == 0 && s > 0) {
334 result = (info.totalram >> s) + (info.totalswap >> s);
341 static void console_init(void)
346 struct serial_struct sr;
349 if ((s = getenv("CONSOLE")) != NULL || (s = getenv("console")) != NULL) {
350 safe_strncpy(console, s, sizeof(console));
352 /* sparc kernel supports console=tty[ab] parameter which is also
353 * passed to init, so catch it here */
354 /* remap tty[ab] to /dev/ttyS[01] */
355 if (strcmp(s, "ttya") == 0)
356 safe_strncpy(console, SC_0, sizeof(console));
357 else if (strcmp(s, "ttyb") == 0)
358 safe_strncpy(console, SC_1, sizeof(console));
361 /* 2.2 kernels: identify the real console backend and try to use it */
362 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
363 /* this is a serial console */
364 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
365 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
366 /* this is linux virtual tty */
367 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
369 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
374 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0 && tried < 2) {
375 /* Can't open selected console -- try
376 logical system console and VT_MASTER */
377 safe_strncpy(console, (tried == 0 ? _PATH_CONSOLE : CURRENT_VC),
382 /* Perhaps we should panic here? */
383 #ifndef CONFIG_SYSLOGD
386 safe_strncpy(console, "/dev/null", sizeof(console));
389 /* check for serial console */
390 if (ioctl(fd, TIOCGSERIAL, &sr) == 0) {
391 /* Force the TERM setting to vt102 for serial console --
392 * if TERM is set to linux (the default) */
393 if (s == NULL || strcmp(s, "linux") == 0)
394 putenv("TERM=vt102");
395 #ifndef CONFIG_SYSLOGD
400 putenv("TERM=linux");
404 messageD(LOG, "console=%s", console);
407 static void fixup_argv(int argc, char **argv, char *new_argv0)
411 /* Fix up argv[0] to be certain we claim to be init */
412 len = strlen(argv[0]);
413 memset(argv[0], 0, len);
414 safe_strncpy(argv[0], new_argv0, len + 1);
416 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
419 memset(argv[len], 0, strlen(argv[len]));
424 static pid_t run(const struct init_action *a)
428 pid_t pid, pgrp, tmp_pid;
429 char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
430 char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
431 sigset_t nmask, omask;
432 static const char press_enter[] =
433 #ifdef CUSTOMIZED_BANNER
434 #include CUSTOMIZED_BANNER
436 "\nPlease press Enter to activate this console. ";
438 /* Block sigchild while forking. */
440 sigaddset(&nmask, SIGCHLD);
441 sigprocmask(SIG_BLOCK, &nmask, &omask);
443 if ((pid = fork()) == 0) {
448 sigprocmask(SIG_SETMASK, &omask, NULL);
450 /* Reset signal handlers that were set by the parent process */
451 signal(SIGUSR1, SIG_DFL);
452 signal(SIGUSR2, SIG_DFL);
453 signal(SIGINT, SIG_DFL);
454 signal(SIGTERM, SIG_DFL);
455 signal(SIGHUP, SIG_DFL);
456 signal(SIGCONT, SIG_DFL);
457 signal(SIGSTOP, SIG_DFL);
458 signal(SIGTSTP, SIG_DFL);
460 /* Create a new session and make ourself the process
464 /* Open the new terminal device */
465 if ((device_open(a->terminal, O_RDWR)) < 0) {
466 if (stat(a->terminal, &sb) != 0) {
467 message(LOG | CONSOLE, "device '%s' does not exist.",
471 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
475 /* Make sure the terminal will act fairly normal for us */
477 /* Setup stdout, stderr for the new process so
478 * they point to the supplied terminal */
482 /* If the init Action requires us to wait, then force the
483 * supplied terminal to be the controlling tty. */
484 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
486 /* Now fork off another process to just hang around */
487 if ((pid = fork()) < 0) {
488 message(LOG | CONSOLE, "Can't fork!");
494 /* We are the parent -- wait till the child is done */
495 signal(SIGINT, SIG_IGN);
496 signal(SIGTSTP, SIG_IGN);
497 signal(SIGQUIT, SIG_IGN);
498 signal(SIGCHLD, SIG_DFL);
500 /* Wait for child to exit */
501 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid);
503 /* See if stealing the controlling tty back is necessary */
505 if (pgrp != getpid())
508 /* Use a temporary process to steal the controlling tty. */
509 if ((pid = fork()) < 0) {
510 message(LOG | CONSOLE, "Can't fork!");
515 ioctl(0, TIOCSCTTY, 1);
518 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
519 if (tmp_pid < 0 && errno == ECHILD)
525 /* Now fall though to actually execute things */
528 /* See if any special /bin/sh requiring characters are present */
529 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
532 cmd[2] = strcat(strcpy(buf, "exec "), a->command);
535 /* Convert command (char*) into cmd (char**, one word per string) */
536 strcpy(buf, a->command);
538 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
539 if (*tmpCmd != '\0') {
550 Interactive shells want to see a dash in argv[0]. This
551 typically is handled by login, argv will be setup this
552 way if a dash appears at the front of the command path
556 if (*cmdpath == '-') {
558 /* skip over the dash */
561 /* find the last component in the command pathname */
562 s = bb_get_last_path_component(cmdpath);
564 /* make a new argv[0] */
565 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
566 message(LOG | CONSOLE, bb_msg_memory_exhausted);
570 strcpy(cmd[0] + 1, s);
574 if (a->action & ASKFIRST) {
577 * Save memory by not exec-ing anything large (like a shell)
578 * before the user wants it. This is critical if swap is not
579 * enabled and the system has low memory. Generally this will
580 * be run on the second virtual console, and the first will
581 * be allowed to start a shell or whatever an init script
584 messageD(LOG, "Waiting for enter to start '%s'"
585 "(pid %d, terminal %s)\n",
586 cmdpath, getpid(), a->terminal);
587 bb_full_write(1, press_enter, sizeof(press_enter) - 1);
588 while(read(0, &c, 1) == 1 && c != '\n')
592 /* Log the process name and args */
593 message(LOG, "Starting pid %d, console %s: '%s'",
594 getpid(), a->terminal, cmdpath);
596 #if defined CONFIG_FEATURE_INIT_COREDUMPS
597 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
600 limit.rlim_cur = RLIM_INFINITY;
601 limit.rlim_max = RLIM_INFINITY;
602 setrlimit(RLIMIT_CORE, &limit);
606 /* Now run it. The new program will take over this PID,
607 * so nothing further in init.c should be run. */
610 /* We're still here? Some error happened. */
611 message(LOG | CONSOLE, "Bummer, could not run '%s': %m", cmdpath);
614 sigprocmask(SIG_SETMASK, &omask, NULL);
618 static int waitfor(const struct init_action *a)
625 wpid = wait(&status);
626 if (wpid > 0 && wpid != pid) {
635 /* Run all commands of a particular type */
636 static void run_actions(int action)
638 struct init_action *a, *tmp;
640 for (a = init_action_list; a; a = tmp) {
642 if (a->action == action) {
643 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
645 delete_init_action(a);
646 } else if (a->action & ONCE) {
648 delete_init_action(a);
649 } else if (a->action & (RESPAWN | ASKFIRST)) {
650 /* Only run stuff with pid==0. If they have
651 * a pid, that means it is still running */
661 static void init_reboot(unsigned long magic)
664 /* We have to fork here, since the kernel calls do_exit(0) in
665 * linux/kernel/sys.c, which can cause the machine to panic when
666 * the init process is killed.... */
667 if ((pid = fork()) == 0) {
668 #if (__GNU_LIBRARY__ > 5) || defined(__dietlibc__)
671 reboot(0xfee1dead, 672274793, magic);
675 waitpid (pid, NULL, 0);
678 static void shutdown_system(void)
680 sigset_t block_signals;
682 /* run everything to be run at "shutdown". This is done _prior_
683 * to killing everything, in case people wish to use scripts to
684 * shut things down gracefully... */
685 run_actions(SHUTDOWN);
687 /* first disable all our signals */
688 sigemptyset(&block_signals);
689 sigaddset(&block_signals, SIGHUP);
690 sigaddset(&block_signals, SIGCHLD);
691 sigaddset(&block_signals, SIGUSR1);
692 sigaddset(&block_signals, SIGUSR2);
693 sigaddset(&block_signals, SIGINT);
694 sigaddset(&block_signals, SIGTERM);
695 sigaddset(&block_signals, SIGCONT);
696 sigaddset(&block_signals, SIGSTOP);
697 sigaddset(&block_signals, SIGTSTP);
698 sigprocmask(SIG_BLOCK, &block_signals, NULL);
700 /* Allow Ctrl-Alt-Del to reboot system. */
701 init_reboot(RB_ENABLE_CAD);
703 message(CONSOLE | LOG, "The system is going down NOW !!");
706 /* Send signals to every process _except_ pid 1 */
707 message(CONSOLE | LOG, "Sending SIGTERM to all processes.");
712 message(CONSOLE | LOG, "Sending SIGKILL to all processes.");
719 static void exec_signal(int sig)
721 struct init_action *a, *tmp;
722 sigset_t unblock_signals;
724 for (a = init_action_list; a; a = tmp) {
726 if (a->action & RESTART) {
731 /* unblock all signals, blocked in shutdown_system() */
732 sigemptyset(&unblock_signals);
733 sigaddset(&unblock_signals, SIGHUP);
734 sigaddset(&unblock_signals, SIGCHLD);
735 sigaddset(&unblock_signals, SIGUSR1);
736 sigaddset(&unblock_signals, SIGUSR2);
737 sigaddset(&unblock_signals, SIGINT);
738 sigaddset(&unblock_signals, SIGTERM);
739 sigaddset(&unblock_signals, SIGCONT);
740 sigaddset(&unblock_signals, SIGSTOP);
741 sigaddset(&unblock_signals, SIGTSTP);
742 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
744 /* Open the new terminal device */
745 if ((device_open(a->terminal, O_RDWR)) < 0) {
746 if (stat(a->terminal, &sb) != 0) {
747 message(LOG | CONSOLE, "device '%s' does not exist.", a->terminal);
749 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
751 halt_signal(SIGUSR1);
754 /* Make sure the terminal will act fairly normal for us */
756 /* Setup stdout, stderr on the supplied terminal */
760 messageD(CONSOLE | LOG, "Trying to re-exec %s", a->command);
761 execl(a->command, a->command, NULL);
763 message(CONSOLE | LOG, "exec of '%s' failed: %m",
767 init_reboot(RB_HALT_SYSTEM);
773 static void halt_signal(int sig)
776 message(CONSOLE | LOG,
778 /* Seems the s390 console is Wierd(tm). */
779 "The system is halted. You may reboot now."
781 "The system is halted. Press Reset or turn off power"
786 /* allow time for last message to reach serial console */
790 init_reboot(RB_POWER_OFF);
792 init_reboot(RB_HALT_SYSTEM);
797 static void reboot_signal(int sig)
800 message(CONSOLE | LOG, "Please stand by while rebooting the system.");
803 /* allow time for last message to reach serial console */
806 init_reboot(RB_AUTOBOOT);
811 static void ctrlaltdel_signal(int sig)
813 run_actions(CTRLALTDEL);
816 /* The SIGSTOP & SIGTSTP handler */
817 static void stop_handler(int sig)
819 int saved_errno = errno;
828 /* The SIGCONT handler */
829 static void cont_handler(int sig)
834 #endif /* ! DEBUG_INIT */
836 static void new_init_action(int action, char *command, const char *cons)
838 struct init_action *new_action, *a;
843 /* do not run entries if console device is not available */
844 if (access(cons, R_OK | W_OK))
846 if (strcmp(cons, "/dev/null") == 0 && (action & ASKFIRST))
849 new_action = calloc((size_t) (1), sizeof(struct init_action));
851 message(LOG | CONSOLE, "Memory allocation failure");
855 /* Append to the end of the list */
856 for (a = init_action_list; a && a->next; a = a->next);
858 a->next = new_action;
860 init_action_list = new_action;
862 strcpy(new_action->command, command);
863 new_action->action = action;
864 strcpy(new_action->terminal, cons);
865 #if 0 /* calloc zeroed always */
868 messageD(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
869 new_action->command, new_action->action, new_action->terminal);
872 static void delete_init_action(struct init_action *action)
874 struct init_action *a, *b = NULL;
876 for (a = init_action_list; a; b = a, a = a->next) {
879 init_action_list = a->next;
889 /* Make sure there is enough memory to do something useful. *
890 * Calls "swapon -a" if needed so be sure /etc/fstab is present... */
891 static void check_memory(void)
895 if (check_free_memory() > 1000)
898 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
899 if (stat("/etc/fstab", &statBuf) == 0) {
900 /* swapon -a requires /proc typically */
901 new_init_action(SYSINIT, "/bin/mount -t proc proc /proc", "");
902 /* Try to turn on swap */
903 new_init_action(SYSINIT, "/sbin/swapon -a", "");
904 run_actions(SYSINIT); /* wait and removing */
905 if (check_free_memory() < 1000)
913 message(CONSOLE, "Sorry, your computer does not have enough memory.");
917 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
918 * then parse_inittab() simply adds in some default
919 * actions(i.e., runs INIT_SCRIPT and then starts a pair
920 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
921 * _is_ defined, but /etc/inittab is missing, this
922 * results in the same set of default behaviors.
924 static void parse_inittab(void)
926 #ifdef CONFIG_FEATURE_USE_INITTAB
928 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
929 char tmpConsole[CONSOLE_BUFF_SIZE];
930 char *id, *runlev, *action, *command, *eol;
931 const struct init_action_type *a = actions;
934 file = fopen(INITTAB, "r");
936 /* No inittab file -- set up some default behavior */
938 /* Reboot on Ctrl-Alt-Del */
939 new_init_action(CTRLALTDEL, "/sbin/reboot", "");
940 /* Umount all filesystems on halt/reboot */
941 new_init_action(SHUTDOWN, "/bin/umount -a -r", "");
942 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
943 /* Swapoff on halt/reboot */
944 new_init_action(SHUTDOWN, "/sbin/swapoff -a", "");
946 /* Prepare to restart init when a HUP is received */
947 new_init_action(RESTART, "/sbin/init", "");
948 /* Askfirst shell on tty1-4 */
949 new_init_action(ASKFIRST, LOGIN_SHELL, "");
950 new_init_action(ASKFIRST, LOGIN_SHELL, VC_2);
951 new_init_action(ASKFIRST, LOGIN_SHELL, VC_3);
952 new_init_action(ASKFIRST, LOGIN_SHELL, VC_4);
954 new_init_action(SYSINIT, INIT_SCRIPT, "");
957 #ifdef CONFIG_FEATURE_USE_INITTAB
960 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
961 /* Skip leading spaces */
962 for (id = buf; *id == ' ' || *id == '\t'; id++);
964 /* Skip the line if it's a comment */
965 if (*id == '#' || *id == '\n')
968 /* Trim the trailing \n */
969 eol = strrchr(id, '\n');
973 /* Keep a copy around for posterity's sake (and error msgs) */
974 strcpy(lineAsRead, buf);
976 /* Separate the ID field from the runlevels */
977 runlev = strchr(id, ':');
978 if (runlev == NULL || *(runlev + 1) == '\0') {
979 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
986 /* Separate the runlevels from the action */
987 action = strchr(runlev, ':');
988 if (action == NULL || *(action + 1) == '\0') {
989 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
996 /* Separate the action from the command */
997 command = strchr(action, ':');
998 if (command == NULL || *(command + 1) == '\0') {
999 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1006 /* Ok, now process it */
1007 for (a = actions; a->name != 0; a++) {
1008 if (strcmp(a->name, action) == 0) {
1010 if(strncmp(id, "/dev/", 5) == 0)
1012 strcpy(tmpConsole, "/dev/");
1013 safe_strncpy(tmpConsole + 5, id,
1014 CONSOLE_BUFF_SIZE - 5);
1017 new_init_action(a->action, command, id);
1022 /* Choke on an unknown action */
1023 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1028 #endif /* CONFIG_FEATURE_USE_INITTAB */
1032 extern int init_main(int argc, char **argv)
1034 struct init_action *a;
1038 if (argc > 1 && !strcmp(argv[1], "-q")) {
1039 return kill_init(SIGHUP);
1042 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1044 #ifdef CONFIG_FEATURE_INITRD
1045 && strstr(bb_applet_name, "linuxrc") == NULL
1050 /* Set up sig handlers -- be sure to
1051 * clear all of these in run() */
1052 signal(SIGHUP, exec_signal);
1053 signal(SIGUSR1, halt_signal);
1054 signal(SIGUSR2, halt_signal);
1055 signal(SIGINT, ctrlaltdel_signal);
1056 signal(SIGTERM, reboot_signal);
1057 signal(SIGCONT, cont_handler);
1058 signal(SIGSTOP, stop_handler);
1059 signal(SIGTSTP, stop_handler);
1061 /* Turn off rebooting via CTL-ALT-DEL -- we get a
1062 * SIGINT on CAD so we can shut things down gracefully... */
1063 init_reboot(RB_DISABLE_CAD);
1066 /* Figure out where the default console should be */
1069 /* Close whatever files are open, and reset the console. */
1074 if (device_open(console, O_RDWR | O_NOCTTY) == 0) {
1082 const char * const *e;
1083 /* Make sure environs is set to something sane */
1084 for(e = environment; *e; e++)
1085 putenv((char *) *e);
1088 message(MAYBE_CONSOLE | LOG, "init started: %s", bb_msg_full_version);
1090 /* Make sure there is enough memory to do something useful. */
1093 /* Check if we are supposed to be in single user mode */
1094 if (argc > 1 && (!strcmp(argv[1], "single") ||
1095 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1096 /* Start a shell on console */
1097 new_init_action(RESPAWN, LOGIN_SHELL, "");
1099 /* Not in single user mode -- see what inittab says */
1101 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1102 * then parse_inittab() simply adds in some default
1103 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1104 * of "askfirst" shells */
1108 /* Make the command line just say "init" -- thats all, nothing else */
1109 fixup_argv(argc, argv, "init");
1111 /* Now run everything that needs to be run */
1113 /* First run the sysinit command */
1114 run_actions(SYSINIT);
1116 /* Next run anything that wants to block */
1119 /* Next run anything to be run only once */
1122 /* If there is nothing else to do, stop */
1123 if (init_action_list == NULL) {
1124 message(LOG | CONSOLE,
1125 "No more tasks for init -- sleeping forever.");
1129 /* Now run the looping stuff for the rest of forever */
1131 /* run the respawn stuff */
1132 run_actions(RESPAWN);
1134 /* run the askfirst stuff */
1135 run_actions(ASKFIRST);
1137 /* Don't consume all CPU time -- sleep a bit */
1140 /* Wait for a child process to exit */
1141 wpid = wait(&status);
1143 /* Find out who died and clean up their corpse */
1144 for (a = init_action_list; a; a = a->next) {
1145 if (a->pid == wpid) {
1146 /* Set the pid to 0 so that the process gets
1147 * restarted by run_actions() */
1149 message(LOG, "Process '%s' (pid %d) exited. "
1150 "Scheduling it for restart.",
1154 /* see if anyone else is waiting to be reaped */
1155 wpid = waitpid (-1, &status, WNOHANG);
1162 c-file-style: "linux"