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) 1999-2003 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/mount.h>
43 #include <sys/types.h>
45 #include <sys/reboot.h>
48 #include "init_shared.h"
52 # include <sys/syslog.h>
56 #if defined(__UCLIBC__) && !defined(__UCLIBC_HAS_MMU__)
60 #define INIT_BUFFS_SIZE 256
62 /* From <linux/vt.h> */
64 unsigned short v_active; /* active vt */
65 unsigned short v_signal; /* signal to send */
66 unsigned short v_state; /* vt bitmask */
68 static const int VT_GETSTATE = 0x5603; /* get global vt state info */
70 /* From <linux/serial.h> */
71 struct serial_struct {
80 unsigned short close_delay;
81 char reserved_char[2];
83 unsigned short closing_wait; /* time to wait before closing */
84 unsigned short closing_wait2; /* no longer used... */
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 SHELL "/bin/sh" /* Default shell */
108 #define LOGIN_SHELL "-" SHELL /* Default login shell */
109 #define INITTAB "/etc/inittab" /* inittab file location */
111 #define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
114 #define MAXENV 16 /* Number of env. vars */
116 #define CONSOLE_BUFF_SIZE 32
118 /* Allowed init action types */
119 #define SYSINIT 0x001
120 #define RESPAWN 0x002
121 #define ASKFIRST 0x004
124 #define CTRLALTDEL 0x020
125 #define SHUTDOWN 0x040
126 #define RESTART 0x080
128 /* A mapping between "inittab" action name strings and action type codes. */
129 struct init_action_type {
134 static const struct init_action_type actions[] = {
135 {"sysinit", SYSINIT},
136 {"respawn", RESPAWN},
137 {"askfirst", ASKFIRST},
140 {"ctrlaltdel", CTRLALTDEL},
141 {"shutdown", SHUTDOWN},
142 {"restart", RESTART},
146 /* Set up a linked list of init_actions, to be read from inittab */
149 char command[INIT_BUFFS_SIZE];
150 char terminal[CONSOLE_BUFF_SIZE];
151 struct init_action *next;
155 /* Static variables */
156 static struct init_action *init_action_list = NULL;
157 static char console[CONSOLE_BUFF_SIZE] = _PATH_CONSOLE;
159 #ifndef CONFIG_SYSLOGD
160 static char *log = VC_5;
162 static sig_atomic_t got_cont = 0;
163 static const int LOG = 0x1;
164 static const int CONSOLE = 0x2;
166 #if defined CONFIG_FEATURE_EXTRA_QUIET
167 static const int MAYBE_CONSOLE = 0x0;
169 #define MAYBE_CONSOLE CONSOLE
171 #ifndef RB_HALT_SYSTEM
172 static const int RB_HALT_SYSTEM = 0xcdef0123;
173 static const int RB_ENABLE_CAD = 0x89abcdef;
174 static const int RB_DISABLE_CAD = 0;
176 #define RB_POWER_OFF 0x4321fedc
177 static const int RB_AUTOBOOT = 0x01234567;
180 static const char * const environment[] = {
182 "PATH=" _PATH_STDPATH,
188 /* Function prototypes */
189 static void delete_init_action(struct init_action *a);
190 static int waitfor(const struct init_action *a);
191 static void halt_signal(int sig);
194 static void loop_forever(void)
200 /* Print a message to the specified device.
201 * Device may be bitwise-or'd from LOG | CONSOLE */
203 static inline void messageD(int device, const char *fmt, ...)
207 #define messageD message
209 static void message(int device, const char *fmt, ...)
210 __attribute__ ((format(printf, 2, 3)));
211 static void message(int device, const char *fmt, ...)
216 #ifndef CONFIG_SYSLOGD
217 static int log_fd = -1;
221 va_start(arguments, fmt);
222 l = vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments) + 1;
225 #ifdef CONFIG_SYSLOGD
226 /* Log the message to syslogd */
228 /* don`t out "\r\n" */
229 syslog_msg(LOG_DAEMON, LOG_INFO, msg + 1);
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, O_RDWR | O_NDELAY | O_NOCTTY)) < 0) {
243 bb_error_msg("Bummer, can't write to log on %s!", log);
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_NDELAY);
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 /* How much memory does this machine have?
312 Units are kBytes to avoid overflow on 4GB machines */
313 static int check_free_memory(void)
316 unsigned int result, u, s = 10;
318 if (sysinfo(&info) != 0) {
319 bb_perror_msg("Error checking free memory");
323 /* Kernels 2.0.x and 2.2.x return info.mem_unit==0 with values in bytes.
324 * Kernels 2.4.0 return info.mem_unit in bytes. */
328 while ((u & 1) == 0 && s > 0) {
332 result = (info.totalram >> s) + (info.totalswap >> s);
339 static void console_init(void)
344 struct serial_struct sr;
347 if ((s = getenv("CONSOLE")) != NULL || (s = getenv("console")) != NULL) {
348 safe_strncpy(console, s, sizeof(console));
350 /* sparc kernel supports console=tty[ab] parameter which is also
351 * passed to init, so catch it here */
352 /* remap tty[ab] to /dev/ttyS[01] */
353 if (strcmp(s, "ttya") == 0)
354 safe_strncpy(console, SC_0, sizeof(console));
355 else if (strcmp(s, "ttyb") == 0)
356 safe_strncpy(console, SC_1, sizeof(console));
359 /* 2.2 kernels: identify the real console backend and try to use it */
360 if (ioctl(0, TIOCGSERIAL, &sr) == 0) {
361 /* this is a serial console */
362 snprintf(console, sizeof(console) - 1, SC_FORMAT, sr.line);
363 } else if (ioctl(0, VT_GETSTATE, &vt) == 0) {
364 /* this is linux virtual tty */
365 snprintf(console, sizeof(console) - 1, VC_FORMAT, vt.v_active);
367 safe_strncpy(console, _PATH_CONSOLE, sizeof(console));
372 while ((fd = open(console, O_RDONLY | O_NONBLOCK)) < 0 && tried < 2) {
373 /* Can't open selected console -- try
374 logical system console and VT_MASTER */
375 safe_strncpy(console, (tried == 0 ? _PATH_CONSOLE : CURRENT_VC),
380 /* Perhaps we should panic here? */
381 #ifndef CONFIG_SYSLOGD
384 safe_strncpy(console, "/dev/null", sizeof(console));
387 /* check for serial console */
388 if (ioctl(fd, TIOCGSERIAL, &sr) == 0) {
389 /* Force the TERM setting to vt102 for serial console --
390 * if TERM is set to linux (the default) */
391 if (s == NULL || strcmp(s, "linux") == 0)
392 putenv("TERM=vt102");
393 #ifndef CONFIG_SYSLOGD
398 putenv("TERM=linux");
402 messageD(LOG, "console=%s", console);
405 static void fixup_argv(int argc, char **argv, char *new_argv0)
409 /* Fix up argv[0] to be certain we claim to be init */
410 len = strlen(argv[0]);
411 memset(argv[0], 0, len);
412 safe_strncpy(argv[0], new_argv0, len + 1);
414 /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
417 memset(argv[len], 0, strlen(argv[len]));
422 static pid_t run(const struct init_action *a)
426 pid_t pid, pgrp, tmp_pid;
427 char *s, *tmpCmd, *cmd[INIT_BUFFS_SIZE], *cmdpath;
428 char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
429 sigset_t nmask, omask;
430 static const char press_enter[] =
431 #ifdef CUSTOMIZED_BANNER
432 #include CUSTOMIZED_BANNER
434 "\nPlease press Enter to activate this console. ";
436 /* Block sigchild while forking. */
438 sigaddset(&nmask, SIGCHLD);
439 sigprocmask(SIG_BLOCK, &nmask, &omask);
441 if ((pid = fork()) == 0) {
446 sigprocmask(SIG_SETMASK, &omask, NULL);
448 /* Reset signal handlers that were set by the parent process */
449 signal(SIGUSR1, SIG_DFL);
450 signal(SIGUSR2, SIG_DFL);
451 signal(SIGINT, SIG_DFL);
452 signal(SIGTERM, SIG_DFL);
453 signal(SIGHUP, SIG_DFL);
454 signal(SIGCONT, SIG_DFL);
455 signal(SIGSTOP, SIG_DFL);
456 signal(SIGTSTP, SIG_DFL);
458 /* Create a new session and make ourself the process
462 /* Open the new terminal device */
463 if ((device_open(a->terminal, O_RDWR)) < 0) {
464 if (stat(a->terminal, &sb) != 0) {
465 message(LOG | CONSOLE, "device '%s' does not exist.",
469 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
473 /* Make sure the terminal will act fairly normal for us */
475 /* Setup stdout, stderr for the new process so
476 * they point to the supplied terminal */
480 /* If the init Action requires us to wait, then force the
481 * supplied terminal to be the controlling tty. */
482 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
484 /* Now fork off another process to just hang around */
485 if ((pid = fork()) < 0) {
486 message(LOG | CONSOLE, "Can't fork!");
492 /* We are the parent -- wait till the child is done */
493 signal(SIGINT, SIG_IGN);
494 signal(SIGTSTP, SIG_IGN);
495 signal(SIGQUIT, SIG_IGN);
496 signal(SIGCHLD, SIG_DFL);
498 /* Wait for child to exit */
499 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid);
501 /* See if stealing the controlling tty back is necessary */
503 if (pgrp != getpid())
506 /* Use a temporary process to steal the controlling tty. */
507 if ((pid = fork()) < 0) {
508 message(LOG | CONSOLE, "Can't fork!");
513 ioctl(0, TIOCSCTTY, 1);
516 while ((tmp_pid = waitpid(pid, &junk, 0)) != pid) {
517 if (tmp_pid < 0 && errno == ECHILD)
523 /* Now fall though to actually execute things */
526 /* See if any special /bin/sh requiring characters are present */
527 if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
530 cmd[2] = strcat(strcpy(buf, "exec "), a->command);
533 /* Convert command (char*) into cmd (char**, one word per string) */
534 strcpy(buf, a->command);
536 for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
537 if (*tmpCmd != '\0') {
548 Interactive shells want to see a dash in argv[0]. This
549 typically is handled by login, argv will be setup this
550 way if a dash appears at the front of the command path
554 if (*cmdpath == '-') {
556 /* skip over the dash */
559 /* find the last component in the command pathname */
560 s = bb_get_last_path_component(cmdpath);
562 /* make a new argv[0] */
563 if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
564 message(LOG | CONSOLE, bb_msg_memory_exhausted);
568 strcpy(cmd[0] + 1, s);
572 if (a->action & ASKFIRST) {
575 * Save memory by not exec-ing anything large (like a shell)
576 * before the user wants it. This is critical if swap is not
577 * enabled and the system has low memory. Generally this will
578 * be run on the second virtual console, and the first will
579 * be allowed to start a shell or whatever an init script
582 messageD(LOG, "Waiting for enter to start '%s'"
583 "(pid %d, terminal %s)\n",
584 cmdpath, getpid(), a->terminal);
585 bb_full_write(1, press_enter, sizeof(press_enter) - 1);
586 while(read(0, &c, 1) == 1 && c != '\n')
590 /* Log the process name and args */
591 message(LOG, "Starting pid %d, console %s: '%s'",
592 getpid(), a->terminal, cmdpath);
594 #if defined CONFIG_FEATURE_INIT_COREDUMPS
595 if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
598 limit.rlim_cur = RLIM_INFINITY;
599 limit.rlim_max = RLIM_INFINITY;
600 setrlimit(RLIMIT_CORE, &limit);
604 /* Now run it. The new program will take over this PID,
605 * so nothing further in init.c should be run. */
608 /* We're still here? Some error happened. */
609 message(LOG | CONSOLE, "Bummer, could not run '%s': %m", cmdpath);
612 sigprocmask(SIG_SETMASK, &omask, NULL);
616 static int waitfor(const struct init_action *a)
623 wpid = wait(&status);
624 if (wpid > 0 && wpid != pid) {
633 /* Run all commands of a particular type */
634 static void run_actions(int action)
636 struct init_action *a, *tmp;
638 for (a = init_action_list; a; a = tmp) {
640 if (a->action == action) {
641 if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
643 delete_init_action(a);
644 } else if (a->action & ONCE) {
646 delete_init_action(a);
647 } else if (a->action & (RESPAWN | ASKFIRST)) {
648 /* Only run stuff with pid==0. If they have
649 * a pid, that means it is still running */
659 static void init_reboot(unsigned long magic)
662 /* We have to fork here, since the kernel calls do_exit(0) in
663 * linux/kernel/sys.c, which can cause the machine to panic when
664 * the init process is killed.... */
665 if ((pid = fork()) == 0) {
669 waitpid (pid, NULL, 0);
672 static void shutdown_system(void)
674 sigset_t block_signals;
676 /* run everything to be run at "shutdown". This is done _prior_
677 * to killing everything, in case people wish to use scripts to
678 * shut things down gracefully... */
679 run_actions(SHUTDOWN);
681 /* first disable all our signals */
682 sigemptyset(&block_signals);
683 sigaddset(&block_signals, SIGHUP);
684 sigaddset(&block_signals, SIGCHLD);
685 sigaddset(&block_signals, SIGUSR1);
686 sigaddset(&block_signals, SIGUSR2);
687 sigaddset(&block_signals, SIGINT);
688 sigaddset(&block_signals, SIGTERM);
689 sigaddset(&block_signals, SIGCONT);
690 sigaddset(&block_signals, SIGSTOP);
691 sigaddset(&block_signals, SIGTSTP);
692 sigprocmask(SIG_BLOCK, &block_signals, NULL);
694 /* Allow Ctrl-Alt-Del to reboot system. */
695 init_reboot(RB_ENABLE_CAD);
697 message(CONSOLE | LOG, "The system is going down NOW !!");
700 /* Send signals to every process _except_ pid 1 */
701 message(CONSOLE | LOG, "Sending SIGTERM to all processes.");
706 message(CONSOLE | LOG, "Sending SIGKILL to all processes.");
713 static void exec_signal(int sig)
715 struct init_action *a, *tmp;
716 sigset_t unblock_signals;
718 for (a = init_action_list; a; a = tmp) {
720 if (a->action & RESTART) {
725 /* unblock all signals, blocked in shutdown_system() */
726 sigemptyset(&unblock_signals);
727 sigaddset(&unblock_signals, SIGHUP);
728 sigaddset(&unblock_signals, SIGCHLD);
729 sigaddset(&unblock_signals, SIGUSR1);
730 sigaddset(&unblock_signals, SIGUSR2);
731 sigaddset(&unblock_signals, SIGINT);
732 sigaddset(&unblock_signals, SIGTERM);
733 sigaddset(&unblock_signals, SIGCONT);
734 sigaddset(&unblock_signals, SIGSTOP);
735 sigaddset(&unblock_signals, SIGTSTP);
736 sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
738 /* Open the new terminal device */
739 if ((device_open(a->terminal, O_RDWR)) < 0) {
740 if (stat(a->terminal, &sb) != 0) {
741 message(LOG | CONSOLE, "device '%s' does not exist.", a->terminal);
743 message(LOG | CONSOLE, "Bummer, can't open %s", a->terminal);
745 halt_signal(SIGUSR1);
748 /* Make sure the terminal will act fairly normal for us */
750 /* Setup stdout, stderr on the supplied terminal */
754 messageD(CONSOLE | LOG, "Trying to re-exec %s", a->command);
755 execl(a->command, a->command, NULL);
757 message(CONSOLE | LOG, "exec of '%s' failed: %m",
761 init_reboot(RB_HALT_SYSTEM);
767 static void halt_signal(int sig)
770 message(CONSOLE | LOG,
772 /* Seems the s390 console is Wierd(tm). */
773 "The system is halted. You may reboot now."
775 "The system is halted. Press Reset or turn off power"
780 /* allow time for last message to reach serial console */
784 init_reboot(RB_POWER_OFF);
786 init_reboot(RB_HALT_SYSTEM);
791 static void reboot_signal(int sig)
794 message(CONSOLE | LOG, "Please stand by while rebooting the system.");
797 /* allow time for last message to reach serial console */
800 init_reboot(RB_AUTOBOOT);
805 static void ctrlaltdel_signal(int sig)
807 run_actions(CTRLALTDEL);
810 /* The SIGSTOP & SIGTSTP handler */
811 static void stop_handler(int sig)
813 int saved_errno = errno;
822 /* The SIGCONT handler */
823 static void cont_handler(int sig)
828 #endif /* ! DEBUG_INIT */
830 static void new_init_action(int action, char *command, const char *cons)
832 struct init_action *new_action, *a;
837 /* do not run entries if console device is not available */
838 if (access(cons, R_OK | W_OK))
840 if (strcmp(cons, "/dev/null") == 0 && (action & ASKFIRST))
843 new_action = calloc((size_t) (1), sizeof(struct init_action));
845 message(LOG | CONSOLE, "Memory allocation failure");
849 /* Append to the end of the list */
850 for (a = init_action_list; a && a->next; a = a->next);
852 a->next = new_action;
854 init_action_list = new_action;
856 strcpy(new_action->command, command);
857 new_action->action = action;
858 strcpy(new_action->terminal, cons);
859 #if 0 /* calloc zeroed always */
862 messageD(LOG|CONSOLE, "command='%s' action='%d' terminal='%s'\n",
863 new_action->command, new_action->action, new_action->terminal);
866 static void delete_init_action(struct init_action *action)
868 struct init_action *a, *b = NULL;
870 for (a = init_action_list; a; b = a, a = a->next) {
873 init_action_list = a->next;
883 /* Make sure there is enough memory to do something useful. *
884 * Calls "swapon -a" if needed so be sure /etc/fstab is present... */
885 static void check_memory(void)
889 if (check_free_memory() > 1000)
892 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
893 if (stat("/etc/fstab", &statBuf) == 0) {
894 /* swapon -a requires /proc typically */
895 new_init_action(SYSINIT, "/bin/mount -t proc proc /proc", "");
896 /* Try to turn on swap */
897 new_init_action(SYSINIT, "/sbin/swapon -a", "");
898 run_actions(SYSINIT); /* wait and removing */
899 if (check_free_memory() < 1000)
907 message(CONSOLE, "Sorry, your computer does not have enough memory.");
911 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
912 * then parse_inittab() simply adds in some default
913 * actions(i.e., runs INIT_SCRIPT and then starts a pair
914 * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
915 * _is_ defined, but /etc/inittab is missing, this
916 * results in the same set of default behaviors.
918 static void parse_inittab(void)
920 #ifdef CONFIG_FEATURE_USE_INITTAB
922 char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
923 char tmpConsole[CONSOLE_BUFF_SIZE];
924 char *id, *runlev, *action, *command, *eol;
925 const struct init_action_type *a = actions;
928 file = fopen(INITTAB, "r");
930 /* No inittab file -- set up some default behavior */
932 /* Reboot on Ctrl-Alt-Del */
933 new_init_action(CTRLALTDEL, "/sbin/reboot", "");
934 /* Umount all filesystems on halt/reboot */
935 new_init_action(SHUTDOWN, "/bin/umount -a -r", "");
936 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
937 /* Swapoff on halt/reboot */
938 new_init_action(SHUTDOWN, "/sbin/swapoff -a", "");
940 /* Prepare to restart init when a HUP is received */
941 new_init_action(RESTART, "/sbin/init", "");
942 /* Askfirst shell on tty1-4 */
943 new_init_action(ASKFIRST, LOGIN_SHELL, "");
944 new_init_action(ASKFIRST, LOGIN_SHELL, VC_2);
945 new_init_action(ASKFIRST, LOGIN_SHELL, VC_3);
946 new_init_action(ASKFIRST, LOGIN_SHELL, VC_4);
948 new_init_action(SYSINIT, INIT_SCRIPT, "");
951 #ifdef CONFIG_FEATURE_USE_INITTAB
954 while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
955 /* Skip leading spaces */
956 for (id = buf; *id == ' ' || *id == '\t'; id++);
958 /* Skip the line if it's a comment */
959 if (*id == '#' || *id == '\n')
962 /* Trim the trailing \n */
963 eol = strrchr(id, '\n');
967 /* Keep a copy around for posterity's sake (and error msgs) */
968 strcpy(lineAsRead, buf);
970 /* Separate the ID field from the runlevels */
971 runlev = strchr(id, ':');
972 if (runlev == NULL || *(runlev + 1) == '\0') {
973 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
980 /* Separate the runlevels from the action */
981 action = strchr(runlev, ':');
982 if (action == NULL || *(action + 1) == '\0') {
983 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
990 /* Separate the action from the command */
991 command = strchr(action, ':');
992 if (command == NULL || *(command + 1) == '\0') {
993 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1000 /* Ok, now process it */
1001 for (a = actions; a->name != 0; a++) {
1002 if (strcmp(a->name, action) == 0) {
1004 if(strncmp(id, "/dev/", 5) == 0)
1006 strcpy(tmpConsole, "/dev/");
1007 safe_strncpy(tmpConsole + 5, id,
1008 CONSOLE_BUFF_SIZE - 5);
1011 new_init_action(a->action, command, id);
1016 /* Choke on an unknown action */
1017 message(LOG | CONSOLE, "Bad inittab entry: %s", lineAsRead);
1022 #endif /* CONFIG_FEATURE_USE_INITTAB */
1026 extern int init_main(int argc, char **argv)
1028 struct init_action *a;
1032 if (argc > 1 && !strcmp(argv[1], "-q")) {
1033 return kill_init(SIGHUP);
1036 /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
1038 #ifdef CONFIG_FEATURE_INITRD
1039 && strstr(bb_applet_name, "linuxrc") == NULL
1044 /* Set up sig handlers -- be sure to
1045 * clear all of these in run() */
1046 signal(SIGHUP, exec_signal);
1047 signal(SIGUSR1, halt_signal);
1048 signal(SIGUSR2, halt_signal);
1049 signal(SIGINT, ctrlaltdel_signal);
1050 signal(SIGTERM, reboot_signal);
1051 signal(SIGCONT, cont_handler);
1052 signal(SIGSTOP, stop_handler);
1053 signal(SIGTSTP, stop_handler);
1055 /* Turn off rebooting via CTL-ALT-DEL -- we get a
1056 * SIGINT on CAD so we can shut things down gracefully... */
1057 init_reboot(RB_DISABLE_CAD);
1060 /* Figure out where the default console should be */
1063 /* Close whatever files are open, and reset the console. */
1068 if (device_open(console, O_RDWR | O_NOCTTY) == 0) {
1076 const char * const *e;
1077 /* Make sure environs is set to something sane */
1078 for(e = environment; *e; e++)
1079 putenv((char *) *e);
1082 message(MAYBE_CONSOLE | LOG, "init started: %s", bb_msg_full_version);
1084 /* Make sure there is enough memory to do something useful. */
1087 /* Check if we are supposed to be in single user mode */
1088 if (argc > 1 && (!strcmp(argv[1], "single") ||
1089 !strcmp(argv[1], "-s") || !strcmp(argv[1], "1"))) {
1090 /* Start a shell on console */
1091 new_init_action(RESPAWN, LOGIN_SHELL, "");
1093 /* Not in single user mode -- see what inittab says */
1095 /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
1096 * then parse_inittab() simply adds in some default
1097 * actions(i.e., runs INIT_SCRIPT and then starts a pair
1098 * of "askfirst" shells */
1102 /* Make the command line just say "init" -- thats all, nothing else */
1103 fixup_argv(argc, argv, "init");
1105 /* Now run everything that needs to be run */
1107 /* First run the sysinit command */
1108 run_actions(SYSINIT);
1110 /* Next run anything that wants to block */
1113 /* Next run anything to be run only once */
1116 /* If there is nothing else to do, stop */
1117 if (init_action_list == NULL) {
1118 message(LOG | CONSOLE,
1119 "No more tasks for init -- sleeping forever.");
1123 /* Now run the looping stuff for the rest of forever */
1125 /* run the respawn stuff */
1126 run_actions(RESPAWN);
1128 /* run the askfirst stuff */
1129 run_actions(ASKFIRST);
1131 /* Don't consume all CPU time -- sleep a bit */
1134 /* Wait for a child process to exit */
1135 wpid = wait(&status);
1137 /* Find out who died and clean up their corpse */
1138 for (a = init_action_list; a; a = a->next) {
1139 if (a->pid == wpid) {
1140 /* Set the pid to 0 so that the process gets
1141 * restarted by run_actions() */
1143 message(LOG, "Process '%s' (pid %d) exited. "
1144 "Scheduling it for restart.",
1148 /* see if anyone else is waiting to be reaped */
1149 wpid = waitpid (-1, &status, WNOHANG);
1156 c-file-style: "linux"