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-rw-r--r--init/init.c942
1 files changed, 942 insertions, 0 deletions
diff --git a/init/init.c b/init/init.c
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index 0000000..5536504
--- /dev/null
+++ b/init/init.c
@@ -0,0 +1,942 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Mini init implementation for busybox
+ *
+ * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ * Adjusted by so many folks, it's impossible to keep track.
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include "libbb.h"
+#include <syslog.h>
+#include <paths.h>
+#include <sys/reboot.h>
+
+/* Was a CONFIG_xxx option. A lot of people were building
+ * not fully functional init by switching it on! */
+#define DEBUG_INIT 0
+
+#define COMMAND_SIZE 256
+#define CONSOLE_NAME_SIZE 32
+#define MAXENV 16 /* Number of env. vars */
+
+/*
+ * When a file named CORE_ENABLE_FLAG_FILE exists, setrlimit is called
+ * before processes are spawned to set core file size as unlimited.
+ * This is for debugging only. Don't use this is production, unless
+ * you want core dumps lying about....
+ */
+#define CORE_ENABLE_FLAG_FILE "/.init_enable_core"
+#include <sys/resource.h>
+
+#define INITTAB "/etc/inittab" /* inittab file location */
+#ifndef INIT_SCRIPT
+#define INIT_SCRIPT "/etc/init.d/rcS" /* Default sysinit script. */
+#endif
+
+/* Allowed init action types */
+#define SYSINIT 0x01
+#define RESPAWN 0x02
+/* like respawn, but wait for <Enter> to be pressed on tty: */
+#define ASKFIRST 0x04
+#define WAIT 0x08
+#define ONCE 0x10
+#define CTRLALTDEL 0x20
+#define SHUTDOWN 0x40
+#define RESTART 0x80
+
+/* Set up a linked list of init_actions, to be read from inittab */
+struct init_action {
+ struct init_action *next;
+ pid_t pid;
+ uint8_t action_type;
+ char terminal[CONSOLE_NAME_SIZE];
+ char command[COMMAND_SIZE];
+};
+
+/* Static variables */
+static struct init_action *init_action_list = NULL;
+
+static const char *log_console = VC_5;
+
+enum {
+ L_LOG = 0x1,
+ L_CONSOLE = 0x2,
+
+#if ENABLE_FEATURE_EXTRA_QUIET
+ MAYBE_CONSOLE = 0x0,
+#else
+ MAYBE_CONSOLE = L_CONSOLE,
+#endif
+
+#ifndef RB_HALT_SYSTEM
+ RB_HALT_SYSTEM = 0xcdef0123, /* FIXME: this overflows enum */
+ RB_ENABLE_CAD = 0x89abcdef,
+ RB_DISABLE_CAD = 0,
+ RB_POWER_OFF = 0x4321fedc,
+ RB_AUTOBOOT = 0x01234567,
+#endif
+};
+
+/* Function prototypes */
+static void halt_reboot_pwoff(int sig) NORETURN;
+
+static void waitfor(pid_t pid)
+{
+ /* waitfor(run(x)): protect against failed fork inside run() */
+ if (pid <= 0)
+ return;
+
+ /* Wait for any child (prevent zombies from exiting orphaned processes)
+ * but exit the loop only when specified one has exited. */
+ while (wait(NULL) != pid)
+ continue;
+}
+
+static void loop_forever(void) NORETURN;
+static void loop_forever(void)
+{
+ while (1)
+ sleep(1);
+}
+
+/* Print a message to the specified device.
+ * "where" may be bitwise-or'd from L_LOG | L_CONSOLE
+ * NB: careful, we can be called after vfork!
+ */
+#define messageD(...) do { if (DEBUG_INIT) message(__VA_ARGS__); } while (0)
+static void message(int where, const char *fmt, ...)
+ __attribute__ ((format(printf, 2, 3)));
+static void message(int where, const char *fmt, ...)
+{
+ static int log_fd = -1;
+ va_list arguments;
+ unsigned l;
+ char msg[128];
+
+ msg[0] = '\r';
+ va_start(arguments, fmt);
+ l = 1 + vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments);
+ if (l > sizeof(msg) - 1)
+ l = sizeof(msg) - 1;
+ msg[l] = '\0';
+ va_end(arguments);
+
+ if (ENABLE_FEATURE_INIT_SYSLOG) {
+ if (where & L_LOG) {
+ /* Log the message to syslogd */
+ openlog("init", 0, LOG_DAEMON);
+ /* don't print "\r" */
+ syslog(LOG_INFO, "%s", msg + 1);
+ closelog();
+ }
+ msg[l++] = '\n';
+ msg[l] = '\0';
+ } else {
+ msg[l++] = '\n';
+ msg[l] = '\0';
+ /* Take full control of the log tty, and never close it.
+ * It's mine, all mine! Muhahahaha! */
+ if (log_fd < 0) {
+ if (!log_console) {
+ log_fd = STDERR_FILENO;
+ } else {
+ log_fd = device_open(log_console, O_WRONLY | O_NONBLOCK | O_NOCTTY);
+ if (log_fd < 0) {
+ bb_error_msg("can't log to %s", log_console);
+ where = L_CONSOLE;
+ } else {
+ close_on_exec_on(log_fd);
+ }
+ }
+ }
+ if (where & L_LOG) {
+ full_write(log_fd, msg, l);
+ if (log_fd == STDERR_FILENO)
+ return; /* don't print dup messages */
+ }
+ }
+
+ if (where & L_CONSOLE) {
+ /* Send console messages to console so people will see them. */
+ full_write(STDERR_FILENO, msg, l);
+ }
+}
+
+/* From <linux/serial.h> */
+struct serial_struct {
+ int type;
+ int line;
+ unsigned int port;
+ int irq;
+ int flags;
+ int xmit_fifo_size;
+ int custom_divisor;
+ int baud_base;
+ unsigned short close_delay;
+ char io_type;
+ char reserved_char[1];
+ int hub6;
+ unsigned short closing_wait; /* time to wait before closing */
+ unsigned short closing_wait2; /* no longer used... */
+ unsigned char *iomem_base;
+ unsigned short iomem_reg_shift;
+ unsigned int port_high;
+ unsigned long iomap_base; /* cookie passed into ioremap */
+ int reserved[1];
+ /* Paranoia (imagine 64bit kernel overwriting 32bit userspace stack) */
+ uint32_t bbox_reserved[16];
+};
+static void console_init(void)
+{
+ struct serial_struct sr;
+ char *s;
+
+ s = getenv("CONSOLE");
+ if (!s)
+ s = getenv("console");
+ if (s) {
+ int fd = open(s, O_RDWR | O_NONBLOCK | O_NOCTTY);
+ if (fd >= 0) {
+ dup2(fd, STDIN_FILENO);
+ dup2(fd, STDOUT_FILENO);
+ xmove_fd(fd, STDERR_FILENO);
+ }
+ messageD(L_LOG, "console='%s'", s);
+ } else {
+ /* Make sure fd 0,1,2 are not closed
+ * (so that they won't be used by future opens) */
+ bb_sanitize_stdio();
+// Users report problems
+// /* Make sure init can't be blocked by writing to stderr */
+// fcntl(STDERR_FILENO, F_SETFL, fcntl(STDERR_FILENO, F_GETFL) | O_NONBLOCK);
+ }
+
+ s = getenv("TERM");
+ if (ioctl(STDIN_FILENO, TIOCGSERIAL, &sr) == 0) {
+ /* Force the TERM setting to vt102 for serial console
+ * if TERM is set to linux (the default) */
+ if (!s || strcmp(s, "linux") == 0)
+ putenv((char*)"TERM=vt102");
+ if (!ENABLE_FEATURE_INIT_SYSLOG)
+ log_console = NULL;
+ } else if (!s)
+ putenv((char*)"TERM=linux");
+}
+
+/* Set terminal settings to reasonable defaults.
+ * NB: careful, we can be called after vfork! */
+static void set_sane_term(void)
+{
+ struct termios tty;
+
+ tcgetattr(STDIN_FILENO, &tty);
+
+ /* set control chars */
+ tty.c_cc[VINTR] = 3; /* C-c */
+ tty.c_cc[VQUIT] = 28; /* C-\ */
+ tty.c_cc[VERASE] = 127; /* C-? */
+ tty.c_cc[VKILL] = 21; /* C-u */
+ tty.c_cc[VEOF] = 4; /* C-d */
+ tty.c_cc[VSTART] = 17; /* C-q */
+ tty.c_cc[VSTOP] = 19; /* C-s */
+ tty.c_cc[VSUSP] = 26; /* C-z */
+
+ /* use line discipline 0 */
+ tty.c_line = 0;
+
+ /* Make it be sane */
+ tty.c_cflag &= CBAUD | CBAUDEX | CSIZE | CSTOPB | PARENB | PARODD;
+ tty.c_cflag |= CREAD | HUPCL | CLOCAL;
+
+ /* input modes */
+ tty.c_iflag = ICRNL | IXON | IXOFF;
+
+ /* output modes */
+ tty.c_oflag = OPOST | ONLCR;
+
+ /* local modes */
+ tty.c_lflag =
+ ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOKE | IEXTEN;
+
+ tcsetattr_stdin_TCSANOW(&tty);
+}
+
+/* Open the new terminal device.
+ * NB: careful, we can be called after vfork! */
+static void open_stdio_to_tty(const char* tty_name, int exit_on_failure)
+{
+ /* empty tty_name means "use init's tty", else... */
+ if (tty_name[0]) {
+ int fd;
+ close(STDIN_FILENO);
+ /* fd can be only < 0 or 0: */
+ fd = device_open(tty_name, O_RDWR);
+ if (fd) {
+ message(L_LOG | L_CONSOLE, "can't open %s: %s",
+ tty_name, strerror(errno));
+ if (exit_on_failure)
+ _exit(EXIT_FAILURE);
+ if (DEBUG_INIT)
+ _exit(2);
+ /* NB: we don't reach this if we were called after vfork.
+ * Thus halt_reboot_pwoff() itself need not be vfork-safe. */
+ halt_reboot_pwoff(SIGUSR1); /* halt the system */
+ }
+ dup2(STDIN_FILENO, STDOUT_FILENO);
+ dup2(STDIN_FILENO, STDERR_FILENO);
+ }
+ set_sane_term();
+}
+
+/* Wrapper around exec:
+ * Takes string (max COMMAND_SIZE chars).
+ * If chars like '>' detected, execs '[-]/bin/sh -c "exec ......."'.
+ * Otherwise splits words on whitespace, deals with leading dash,
+ * and uses plain exec().
+ * NB: careful, we can be called after vfork!
+ */
+static void init_exec(const char *command)
+{
+ char *cmd[COMMAND_SIZE / 2];
+ char buf[COMMAND_SIZE + 6]; /* COMMAND_SIZE+strlen("exec ")+1 */
+ int dash = (command[0] == '-' /* maybe? && command[1] == '/' */);
+
+ /* See if any special /bin/sh requiring characters are present */
+ if (strpbrk(command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
+ strcpy(buf, "exec ");
+ strcpy(buf + 5, command + dash); /* excluding "-" */
+ /* NB: LIBBB_DEFAULT_LOGIN_SHELL define has leading dash */
+ cmd[0] = (char*)(LIBBB_DEFAULT_LOGIN_SHELL + !dash);
+ cmd[1] = (char*)"-c";
+ cmd[2] = buf;
+ cmd[3] = NULL;
+ } else {
+ /* Convert command (char*) into cmd (char**, one word per string) */
+ char *word, *next;
+ int i = 0;
+ next = strcpy(buf, command); /* including "-" */
+ while ((word = strsep(&next, " \t")) != NULL) {
+ if (*word != '\0') { /* not two spaces/tabs together? */
+ cmd[i] = word;
+ i++;
+ }
+ }
+ cmd[i] = NULL;
+ }
+ /* If we saw leading "-", it is interactive shell.
+ * Try harder to give it a controlling tty.
+ * And skip "-" in actual exec call. */
+ if (dash) {
+ /* _Attempt_ to make stdin a controlling tty. */
+ if (ENABLE_FEATURE_INIT_SCTTY)
+ ioctl(STDIN_FILENO, TIOCSCTTY, 0 /*only try, don't steal*/);
+ }
+ BB_EXECVP(cmd[0] + dash, cmd);
+ message(L_LOG | L_CONSOLE, "cannot run '%s': %s", cmd[0], strerror(errno));
+ /* returns if execvp fails */
+}
+
+/* Used only by run_actions */
+static pid_t run(const struct init_action *a)
+{
+ pid_t pid;
+ sigset_t nmask, omask;
+
+ /* Block sigchild while forking (why?) */
+ sigemptyset(&nmask);
+ sigaddset(&nmask, SIGCHLD);
+ sigprocmask(SIG_BLOCK, &nmask, &omask);
+ if (BB_MMU && (a->action_type & ASKFIRST))
+ pid = fork();
+ else
+ pid = vfork();
+ sigprocmask(SIG_SETMASK, &omask, NULL);
+
+ if (pid < 0)
+ message(L_LOG | L_CONSOLE, "can't fork");
+ if (pid)
+ return pid;
+
+ /* Child */
+
+ /* Reset signal handlers that were set by the parent process */
+ bb_signals(0
+ + (1 << SIGUSR1)
+ + (1 << SIGUSR2)
+ + (1 << SIGINT)
+ + (1 << SIGTERM)
+ + (1 << SIGHUP)
+ + (1 << SIGQUIT)
+ + (1 << SIGCONT)
+ + (1 << SIGSTOP)
+ + (1 << SIGTSTP)
+ , SIG_DFL);
+
+ /* Create a new session and make ourself the process
+ * group leader */
+ setsid();
+
+ /* Open the new terminal device */
+ open_stdio_to_tty(a->terminal, 1 /* - exit if open fails */);
+
+// NB: do not enable unless you change vfork to fork above
+#ifdef BUT_RUN_ACTIONS_ALREADY_DOES_WAITING
+ /* If the init Action requires us to wait, then force the
+ * supplied terminal to be the controlling tty. */
+ if (a->action_type & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
+ /* Now fork off another process to just hang around */
+ pid = fork();
+ if (pid < 0) {
+ message(L_LOG | L_CONSOLE, "can't fork");
+ _exit(EXIT_FAILURE);
+ }
+
+ if (pid > 0) {
+ /* Parent - wait till the child is done */
+ bb_signals(0
+ + (1 << SIGINT)
+ + (1 << SIGTSTP)
+ + (1 << SIGQUIT)
+ , SIG_IGN);
+ signal(SIGCHLD, SIG_DFL);
+
+ waitfor(pid);
+ /* See if stealing the controlling tty back is necessary */
+ if (tcgetpgrp(0) != getpid())
+ _exit(EXIT_SUCCESS);
+
+ /* Use a temporary process to steal the controlling tty. */
+ pid = fork();
+ if (pid < 0) {
+ message(L_LOG | L_CONSOLE, "can't fork");
+ _exit(EXIT_FAILURE);
+ }
+ if (pid == 0) {
+ setsid();
+ ioctl(0, TIOCSCTTY, 1);
+ _exit(EXIT_SUCCESS);
+ }
+ waitfor(pid);
+ _exit(EXIT_SUCCESS);
+ }
+ /* Child - fall though to actually execute things */
+ }
+#endif
+
+ /* NB: on NOMMU we can't wait for input in child, so
+ * "askfirst" will work the same as "respawn". */
+ if (BB_MMU && (a->action_type & ASKFIRST)) {
+ static const char press_enter[] ALIGN1 =
+#ifdef CUSTOMIZED_BANNER
+#include CUSTOMIZED_BANNER
+#endif
+ "\nPlease press Enter to activate this console. ";
+ char c;
+ /*
+ * Save memory by not exec-ing anything large (like a shell)
+ * before the user wants it. This is critical if swap is not
+ * enabled and the system has low memory. Generally this will
+ * be run on the second virtual console, and the first will
+ * be allowed to start a shell or whatever an init script
+ * specifies.
+ */
+ messageD(L_LOG, "waiting for enter to start '%s'"
+ "(pid %d, tty '%s')\n",
+ a->command, getpid(), a->terminal);
+ full_write(STDOUT_FILENO, press_enter, sizeof(press_enter) - 1);
+ while (safe_read(STDIN_FILENO, &c, 1) == 1 && c != '\n')
+ continue;
+ }
+
+ if (ENABLE_FEATURE_INIT_COREDUMPS) {
+ struct stat sb;
+ if (stat(CORE_ENABLE_FLAG_FILE, &sb) == 0) {
+ struct rlimit limit;
+ limit.rlim_cur = RLIM_INFINITY;
+ limit.rlim_max = RLIM_INFINITY;
+ setrlimit(RLIMIT_CORE, &limit);
+ }
+ }
+
+ /* Log the process name and args */
+ message(L_LOG, "starting pid %d, tty '%s': '%s'",
+ getpid(), a->terminal, a->command);
+
+ /* Now run it. The new program will take over this PID,
+ * so nothing further in init.c should be run. */
+ init_exec(a->command);
+ /* We're still here? Some error happened. */
+ _exit(-1);
+}
+
+static void delete_init_action(struct init_action *action)
+{
+ struct init_action *a, *b = NULL;
+
+ for (a = init_action_list; a; b = a, a = a->next) {
+ if (a == action) {
+ if (b == NULL) {
+ init_action_list = a->next;
+ } else {
+ b->next = a->next;
+ }
+ free(a);
+ break;
+ }
+ }
+}
+
+/* Run all commands of a particular type */
+static void run_actions(int action_type)
+{
+ struct init_action *a, *tmp;
+
+ for (a = init_action_list; a; a = tmp) {
+ tmp = a->next;
+ if (a->action_type & action_type) {
+ // Pointless: run() will error out if open of device fails.
+ ///* a->terminal of "" means "init's console" */
+ //if (a->terminal[0] && access(a->terminal, R_OK | W_OK)) {
+ // //message(L_LOG | L_CONSOLE, "Device %s cannot be opened in RW mode", a->terminal /*, strerror(errno)*/);
+ // delete_init_action(a);
+ //} else
+ if (a->action_type & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
+ waitfor(run(a));
+ delete_init_action(a);
+ } else if (a->action_type & ONCE) {
+ run(a);
+ delete_init_action(a);
+ } else if (a->action_type & (RESPAWN | ASKFIRST)) {
+ /* Only run stuff with pid==0. If they have
+ * a pid, that means it is still running */
+ if (a->pid == 0) {
+ a->pid = run(a);
+ }
+ }
+ }
+ }
+}
+
+static void init_reboot(unsigned long magic)
+{
+ pid_t pid;
+ /* We have to fork here, since the kernel calls do_exit(EXIT_SUCCESS) in
+ * linux/kernel/sys.c, which can cause the machine to panic when
+ * the init process is killed.... */
+ pid = vfork();
+ if (pid == 0) { /* child */
+ reboot(magic);
+ _exit(EXIT_SUCCESS);
+ }
+ waitfor(pid);
+}
+
+static void kill_all_processes(void)
+{
+ /* run everything to be run at "shutdown". This is done _prior_
+ * to killing everything, in case people wish to use scripts to
+ * shut things down gracefully... */
+ run_actions(SHUTDOWN);
+
+ /* first disable all our signals */
+ sigprocmask_allsigs(SIG_BLOCK);
+
+ message(L_CONSOLE | L_LOG, "The system is going down NOW!");
+
+ /* Allow Ctrl-Alt-Del to reboot system. */
+ init_reboot(RB_ENABLE_CAD);
+
+ /* Send signals to every process _except_ pid 1 */
+ message(L_CONSOLE | L_LOG, "Sending SIG%s to all processes", "TERM");
+ kill(-1, SIGTERM);
+ sync();
+ sleep(1);
+
+ message(L_CONSOLE | L_LOG, "Sending SIG%s to all processes", "KILL");
+ kill(-1, SIGKILL);
+ sync();
+ sleep(1);
+}
+
+static void halt_reboot_pwoff(int sig)
+{
+ const char *m = "halt";
+ int rb;
+
+ kill_all_processes();
+
+ rb = RB_HALT_SYSTEM;
+ if (sig == SIGTERM) {
+ m = "reboot";
+ rb = RB_AUTOBOOT;
+ } else if (sig == SIGUSR2) {
+ m = "poweroff";
+ rb = RB_POWER_OFF;
+ }
+ message(L_CONSOLE | L_LOG, "Requesting system %s", m);
+ /* allow time for last message to reach serial console */
+ sleep(2);
+ init_reboot(rb);
+ loop_forever();
+}
+
+/* Handler for QUIT - exec "restart" action,
+ * else (no such action defined) do nothing */
+static void exec_restart_action(int sig UNUSED_PARAM)
+{
+ struct init_action *a;
+
+ for (a = init_action_list; a; a = a->next) {
+ if (a->action_type & RESTART) {
+ kill_all_processes();
+
+ /* unblock all signals (blocked in kill_all_processes()) */
+ sigprocmask_allsigs(SIG_UNBLOCK);
+
+ /* Open the new terminal device */
+ open_stdio_to_tty(a->terminal, 0 /* - halt if open fails */);
+
+ messageD(L_CONSOLE | L_LOG, "Trying to re-exec %s", a->command);
+ init_exec(a->command);
+ sleep(2);
+ init_reboot(RB_HALT_SYSTEM);
+ loop_forever();
+ }
+ }
+}
+
+static void ctrlaltdel_signal(int sig UNUSED_PARAM)
+{
+ run_actions(CTRLALTDEL);
+}
+
+/* The SIGCONT handler is set to record_signo().
+ * It just sets bb_got_signal = SIGCONT. */
+
+/* The SIGSTOP & SIGTSTP handler */
+static void stop_handler(int sig UNUSED_PARAM)
+{
+ int saved_errno = errno;
+
+ bb_got_signal = 0;
+ while (bb_got_signal == 0)
+ pause();
+
+ errno = saved_errno;
+}
+
+static void new_init_action(uint8_t action_type, const char *command, const char *cons)
+{
+ struct init_action *a, *last;
+
+// Why?
+// if (strcmp(cons, bb_dev_null) == 0 && (action & ASKFIRST))
+// return;
+
+ /* Append to the end of the list */
+ for (a = last = init_action_list; a; a = a->next) {
+ /* don't enter action if it's already in the list,
+ * but do overwrite existing actions */
+ if ((strcmp(a->command, command) == 0)
+ && (strcmp(a->terminal, cons) == 0)
+ ) {
+ a->action_type = action_type;
+ return;
+ }
+ last = a;
+ }
+
+ a = xzalloc(sizeof(*a));
+ if (last) {
+ last->next = a;
+ } else {
+ init_action_list = a;
+ }
+ a->action_type = action_type;
+ safe_strncpy(a->command, command, sizeof(a->command));
+ safe_strncpy(a->terminal, cons, sizeof(a->terminal));
+ messageD(L_LOG | L_CONSOLE, "command='%s' action=%d tty='%s'\n",
+ a->command, a->action_type, a->terminal);
+}
+
+/* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
+ * then parse_inittab() simply adds in some default
+ * actions(i.e., runs INIT_SCRIPT and then starts a pair
+ * of "askfirst" shells). If CONFIG_FEATURE_USE_INITTAB
+ * _is_ defined, but /etc/inittab is missing, this
+ * results in the same set of default behaviors.
+ */
+static void parse_inittab(void)
+{
+#if ENABLE_FEATURE_USE_INITTAB
+ char *token[4];
+ parser_t *parser = config_open2("/etc/inittab", fopen_for_read);
+
+ if (parser == NULL)
+#endif
+ {
+ /* No inittab file -- set up some default behavior */
+ /* Reboot on Ctrl-Alt-Del */
+ new_init_action(CTRLALTDEL, "reboot", "");
+ /* Umount all filesystems on halt/reboot */
+ new_init_action(SHUTDOWN, "umount -a -r", "");
+ /* Swapoff on halt/reboot */
+ if (ENABLE_SWAPONOFF)
+ new_init_action(SHUTDOWN, "swapoff -a", "");
+ /* Prepare to restart init when a QUIT is received */
+ new_init_action(RESTART, "init", "");
+ /* Askfirst shell on tty1-4 */
+ new_init_action(ASKFIRST, bb_default_login_shell, "");
+//TODO: VC_1 instead of ""? "" is console -> ctty problems -> angry users
+ new_init_action(ASKFIRST, bb_default_login_shell, VC_2);
+ new_init_action(ASKFIRST, bb_default_login_shell, VC_3);
+ new_init_action(ASKFIRST, bb_default_login_shell, VC_4);
+ /* sysinit */
+ new_init_action(SYSINIT, INIT_SCRIPT, "");
+ return;
+ }
+
+#if ENABLE_FEATURE_USE_INITTAB
+ /* optional_tty:ignored_runlevel:action:command
+ * Delims are not to be collapsed and need exactly 4 tokens
+ */
+ while (config_read(parser, token, 4, 0, "#:",
+ PARSE_NORMAL & ~(PARSE_TRIM | PARSE_COLLAPSE))) {
+ /* order must correspond to SYSINIT..RESTART constants */
+ static const char actions[] ALIGN1 =
+ "sysinit\0""respawn\0""askfirst\0""wait\0""once\0"
+ "ctrlaltdel\0""shutdown\0""restart\0";
+ int action;
+ char *tty = token[0];
+
+ if (!token[3]) /* less than 4 tokens */
+ goto bad_entry;
+ action = index_in_strings(actions, token[2]);
+ if (action < 0 || !token[3][0]) /* token[3]: command */
+ goto bad_entry;
+ /* turn .*TTY -> /dev/TTY */
+ if (tty[0]) {
+ if (strncmp(tty, "/dev/", 5) == 0)
+ tty += 5;
+ tty = concat_path_file("/dev/", tty);
+ }
+ new_init_action(1 << action, token[3], tty);
+ if (tty[0])
+ free(tty);
+ continue;
+ bad_entry:
+ message(L_LOG | L_CONSOLE, "Bad inittab entry at line %d",
+ parser->lineno);
+ }
+ config_close(parser);
+#endif
+}
+
+#if ENABLE_FEATURE_USE_INITTAB
+static void reload_signal(int sig UNUSED_PARAM)
+{
+ struct init_action *a, *tmp;
+
+ message(L_LOG, "reloading /etc/inittab");
+
+ /* disable old entrys */
+ for (a = init_action_list; a; a = a->next) {
+ a->action_type = ONCE;
+ }
+
+ parse_inittab();
+
+ if (ENABLE_FEATURE_KILL_REMOVED) {
+ /* Be nice and send SIGTERM first */
+ for (a = init_action_list; a; a = a->next) {
+ pid_t pid = a->pid;
+ if ((a->action_type & ONCE) && pid != 0) {
+ kill(pid, SIGTERM);
+ }
+ }
+#if CONFIG_FEATURE_KILL_DELAY
+ /* NB: parent will wait in NOMMU case */
+ if ((BB_MMU ? fork() : vfork()) == 0) { /* child */
+ sleep(CONFIG_FEATURE_KILL_DELAY);
+ for (a = init_action_list; a; a = a->next) {
+ pid_t pid = a->pid;
+ if ((a->action_type & ONCE) && pid != 0) {
+ kill(pid, SIGKILL);
+ }
+ }
+ _exit(EXIT_SUCCESS);
+ }
+#endif
+ }
+
+ /* remove unused entrys */
+ for (a = init_action_list; a; a = tmp) {
+ tmp = a->next;
+ if ((a->action_type & (ONCE | SYSINIT | WAIT)) && a->pid == 0) {
+ delete_init_action(a);
+ }
+ }
+ run_actions(RESPAWN | ASKFIRST);
+}
+#endif
+
+int init_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int init_main(int argc UNUSED_PARAM, char **argv)
+{
+ struct init_action *a;
+ pid_t wpid;
+
+ die_sleep = 30 * 24*60*60; /* if xmalloc will ever die... */
+
+ if (argv[1] && !strcmp(argv[1], "-q")) {
+ return kill(1, SIGHUP);
+ }
+
+ if (!DEBUG_INIT) {
+ /* Expect to be invoked as init with PID=1 or be invoked as linuxrc */
+ if (getpid() != 1
+ && (!ENABLE_FEATURE_INITRD || !strstr(applet_name, "linuxrc"))
+ ) {
+ bb_show_usage();
+ }
+ /* Set up sig handlers -- be sure to
+ * clear all of these in run() */
+ signal(SIGQUIT, exec_restart_action);
+ bb_signals(0
+ + (1 << SIGUSR1) /* halt */
+ + (1 << SIGUSR2) /* poweroff */
+ + (1 << SIGTERM) /* reboot */
+ , halt_reboot_pwoff);
+ signal(SIGINT, ctrlaltdel_signal);
+ signal(SIGCONT, record_signo);
+ bb_signals(0
+ + (1 << SIGSTOP)
+ + (1 << SIGTSTP)
+ , stop_handler);
+
+ /* Turn off rebooting via CTL-ALT-DEL -- we get a
+ * SIGINT on CAD so we can shut things down gracefully... */
+ init_reboot(RB_DISABLE_CAD);
+ }
+
+ /* Figure out where the default console should be */
+ console_init();
+ set_sane_term();
+ xchdir("/");
+ setsid();
+
+ /* Make sure environs is set to something sane */
+ putenv((char *) "HOME=/");
+ putenv((char *) bb_PATH_root_path);
+ putenv((char *) "SHELL=/bin/sh");
+ putenv((char *) "USER=root"); /* needed? why? */
+
+ if (argv[1])
+ xsetenv("RUNLEVEL", argv[1]);
+
+ /* Hello world */
+ message(MAYBE_CONSOLE | L_LOG, "init started: %s", bb_banner);
+
+ /* Make sure there is enough memory to do something useful. */
+ if (ENABLE_SWAPONOFF) {
+ struct sysinfo info;
+
+ if (!sysinfo(&info) &&
+ (info.mem_unit ? : 1) * (long long)info.totalram < 1024*1024)
+ {
+ message(L_CONSOLE, "Low memory, forcing swapon");
+ /* swapon -a requires /proc typically */
+ new_init_action(SYSINIT, "mount -t proc proc /proc", "");
+ /* Try to turn on swap */
+ new_init_action(SYSINIT, "swapon -a", "");
+ run_actions(SYSINIT); /* wait and removing */
+ }
+ }
+
+ /* Check if we are supposed to be in single user mode */
+ if (argv[1]
+ && (!strcmp(argv[1], "single") || !strcmp(argv[1], "-s") || LONE_CHAR(argv[1], '1'))
+ ) {
+ /* ??? shouldn't we set RUNLEVEL="b" here? */
+ /* Start a shell on console */
+ new_init_action(RESPAWN, bb_default_login_shell, "");
+ } else {
+ /* Not in single user mode -- see what inittab says */
+
+ /* NOTE that if CONFIG_FEATURE_USE_INITTAB is NOT defined,
+ * then parse_inittab() simply adds in some default
+ * actions(i.e., runs INIT_SCRIPT and then starts a pair
+ * of "askfirst" shells */
+ parse_inittab();
+ }
+
+#if ENABLE_SELINUX
+ if (getenv("SELINUX_INIT") == NULL) {
+ int enforce = 0;
+
+ putenv((char*)"SELINUX_INIT=YES");
+ if (selinux_init_load_policy(&enforce) == 0) {
+ BB_EXECVP(argv[0], argv);
+ } else if (enforce > 0) {
+ /* SELinux in enforcing mode but load_policy failed */
+ message(L_CONSOLE, "cannot load SELinux Policy. "
+ "Machine is in enforcing mode. Halting now.");
+ exit(EXIT_FAILURE);
+ }
+ }
+#endif /* CONFIG_SELINUX */
+
+ /* Make the command line just say "init" - thats all, nothing else */
+ strncpy(argv[0], "init", strlen(argv[0]));
+ /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
+ while (*++argv)
+ memset(*argv, 0, strlen(*argv));
+
+ /* Now run everything that needs to be run */
+
+ /* First run the sysinit command */
+ run_actions(SYSINIT);
+
+ /* Next run anything that wants to block */
+ run_actions(WAIT);
+
+ /* Next run anything to be run only once */
+ run_actions(ONCE);
+
+ /* Redefine SIGHUP to reread /etc/inittab */
+#if ENABLE_FEATURE_USE_INITTAB
+ signal(SIGHUP, reload_signal);
+#else
+ signal(SIGHUP, SIG_IGN);
+#endif
+
+ /* Now run the looping stuff for the rest of forever */
+ while (1) {
+ /* run the respawn/askfirst stuff */
+ run_actions(RESPAWN | ASKFIRST);
+
+ /* Don't consume all CPU time -- sleep a bit */
+ sleep(1);
+
+ /* Wait for any child process to exit */
+ wpid = wait(NULL);
+ while (wpid > 0) {
+ /* Find out who died and clean up their corpse */
+ for (a = init_action_list; a; a = a->next) {
+ if (a->pid == wpid) {
+ /* Set the pid to 0 so that the process gets
+ * restarted by run_actions() */
+ a->pid = 0;
+ message(L_LOG, "process '%s' (pid %d) exited. "
+ "Scheduling for restart.",
+ a->command, wpid);
+ }
+ }
+ /* see if anyone else is waiting to be reaped */
+ wpid = wait_any_nohang(NULL);
+ }
+ }
+}