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Diffstat (limited to 'i/pc104/initrd/conf/busybox/init/init.c')
-rw-r--r--i/pc104/initrd/conf/busybox/init/init.c1043
1 files changed, 1043 insertions, 0 deletions
diff --git a/i/pc104/initrd/conf/busybox/init/init.c b/i/pc104/initrd/conf/busybox/init/init.c
new file mode 100644
index 0000000..02a3327
--- /dev/null
+++ b/i/pc104/initrd/conf/busybox/init/init.c
@@ -0,0 +1,1043 @@
+/* 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 "busybox.h"
+#include <paths.h>
+#include <signal.h>
+#include <sys/ioctl.h>
+#include <sys/wait.h>
+#include <sys/reboot.h>
+
+#if ENABLE_FEATURE_INIT_SYSLOG
+# include <sys/syslog.h>
+#endif
+
+#define INIT_BUFFS_SIZE 256
+#define CONSOLE_NAME_SIZE 32
+#define MAXENV 16 /* Number of env. vars */
+
+#ifndef _PATH_STDPATH
+#define _PATH_STDPATH "/usr/bin:/bin:/usr/sbin:/sbin"
+#endif
+
+#if ENABLE_FEATURE_INIT_COREDUMPS
+/*
+ * 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>
+#endif
+
+#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 0x001
+#define RESPAWN 0x002
+#define ASKFIRST 0x004
+#define WAIT 0x008
+#define ONCE 0x010
+#define CTRLALTDEL 0x020
+#define SHUTDOWN 0x040
+#define RESTART 0x080
+
+/* A mapping between "inittab" action name strings and action type codes. */
+struct init_action_type {
+ const char *name;
+ int action;
+};
+
+static const struct init_action_type actions[] = {
+ {"sysinit", SYSINIT},
+ {"respawn", RESPAWN},
+ {"askfirst", ASKFIRST},
+ {"wait", WAIT},
+ {"once", ONCE},
+ {"ctrlaltdel", CTRLALTDEL},
+ {"shutdown", SHUTDOWN},
+ {"restart", RESTART},
+ {0, 0}
+};
+
+/* Set up a linked list of init_actions, to be read from inittab */
+struct init_action {
+ struct init_action *next;
+ int action;
+ pid_t pid;
+ char command[INIT_BUFFS_SIZE];
+ char terminal[CONSOLE_NAME_SIZE];
+};
+
+/* Static variables */
+static struct init_action *init_action_list = NULL;
+
+#if !ENABLE_FEATURE_INIT_SYSLOG
+static const char *log_console = VC_5;
+#endif
+#if !ENABLE_DEBUG_INIT
+static sig_atomic_t got_cont = 0;
+#endif
+
+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
+};
+
+static const char * const environment[] = {
+ "HOME=/",
+ "PATH=" _PATH_STDPATH,
+ "SHELL=/bin/sh",
+ "USER=root",
+ NULL
+};
+
+/* Function prototypes */
+static void delete_init_action(struct init_action *a);
+static int waitfor(const struct init_action *a, pid_t pid);
+#if !ENABLE_DEBUG_INIT
+static void shutdown_signal(int sig);
+#endif
+
+#if !ENABLE_DEBUG_INIT
+static void loop_forever(void)
+{
+ while (1)
+ sleep(1);
+}
+#endif
+
+/* Print a message to the specified device.
+ * Device may be bitwise-or'd from L_LOG | L_CONSOLE */
+#if ENABLE_DEBUG_INIT
+#define messageD message
+#else
+#define messageD(...) do {} while (0)
+#endif
+static void message(int device, const char *fmt, ...)
+ __attribute__ ((format(printf, 2, 3)));
+static void message(int device, const char *fmt, ...)
+{
+#if !ENABLE_FEATURE_INIT_SYSLOG
+ static int log_fd = -1;
+#endif
+
+ va_list arguments;
+ int l;
+ char msg[128];
+
+ msg[0] = '\r';
+ va_start(arguments, fmt);
+ vsnprintf(msg + 1, sizeof(msg) - 2, fmt, arguments);
+ va_end(arguments);
+ msg[sizeof(msg) - 2] = '\0';
+ l = strlen(msg);
+
+#if ENABLE_FEATURE_INIT_SYSLOG
+ /* Log the message to syslogd */
+ if (device & L_LOG) {
+ /* don't out "\r" */
+ openlog(applet_name, 0, LOG_DAEMON);
+ syslog(LOG_INFO, "init: %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 = 2;
+ } 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);
+ device = L_CONSOLE;
+ } else {
+ fcntl(log_fd, F_SETFD, FD_CLOEXEC);
+ }
+ }
+ }
+ if (device & L_LOG) {
+ full_write(log_fd, msg, l);
+ if (log_fd == 2)
+ return; /* don't print dup messages */
+ }
+#endif
+
+ if (device & L_CONSOLE) {
+ /* Send console messages to console so people will see them. */
+ full_write(2, msg, l);
+ }
+}
+
+/* Set terminal settings to reasonable defaults */
+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 dicipline 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_FILENO, TCSANOW, &tty);
+}
+
+/* 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, 0);
+ dup2(fd, 1);
+ dup2(fd, 2);
+ while (fd > 2) close(fd--);
+ }
+ messageD(L_LOG, "console='%s'", s);
+ }
+
+ s = getenv("TERM");
+ if (ioctl(0, 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;
+#endif
+ } else if (!s)
+ putenv((char*)"TERM=linux");
+}
+
+static void fixup_argv(int argc, char **argv, const char *new_argv0)
+{
+ int len;
+
+ /* Fix up argv[0] to be certain we claim to be init */
+ len = strlen(argv[0]);
+ strncpy(argv[0], new_argv0, len);
+
+ /* Wipe argv[1]-argv[N] so they don't clutter the ps listing */
+ len = 1;
+ while (argc > len) {
+ memset(argv[len], 0, strlen(argv[len]));
+ len++;
+ }
+}
+
+/* Open the new terminal device */
+static void open_stdio_to_tty(const char* tty_name, int fail)
+{
+ /* empty tty_name means "use init's tty", else... */
+ if (tty_name[0]) {
+ int fd = device_open(tty_name, O_RDWR);
+ if (fd < 0) {
+ message(L_LOG | L_CONSOLE, "Can't open %s: %s",
+ tty_name, strerror(errno));
+ if (fail)
+ _exit(1);
+#if !ENABLE_DEBUG_INIT
+ shutdown_signal(SIGUSR1);
+#else
+ _exit(2);
+#endif
+ } else {
+ dup2(fd, 0);
+ dup2(fd, 1);
+ dup2(fd, 2);
+ if (fd > 2) close(fd);
+ }
+ }
+ set_sane_term();
+}
+
+static pid_t run(const struct init_action *a)
+{
+ int i;
+ pid_t pid;
+ char *s, *tmpCmd, *cmdpath;
+ char *cmd[INIT_BUFFS_SIZE];
+ char buf[INIT_BUFFS_SIZE + 6]; /* INIT_BUFFS_SIZE+strlen("exec ")+1 */
+ sigset_t nmask, omask;
+
+ /* Block sigchild while forking. */
+ sigemptyset(&nmask);
+ sigaddset(&nmask, SIGCHLD);
+ sigprocmask(SIG_BLOCK, &nmask, &omask);
+ pid = fork();
+ sigprocmask(SIG_SETMASK, &omask, NULL);
+
+ if (pid)
+ return pid;
+
+ /* Reset signal handlers that were set by the parent process */
+ signal(SIGUSR1, SIG_DFL);
+ signal(SIGUSR2, SIG_DFL);
+ signal(SIGINT, SIG_DFL);
+ signal(SIGTERM, SIG_DFL);
+ signal(SIGHUP, SIG_DFL);
+ signal(SIGQUIT, SIG_DFL);
+ signal(SIGCONT, SIG_DFL);
+ signal(SIGSTOP, SIG_DFL);
+ signal(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);
+
+ /* If the init Action requires us to wait, then force the
+ * supplied terminal to be the controlling tty. */
+ if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
+
+ /* Now fork off another process to just hang around */
+ if ((pid = fork()) < 0) {
+ message(L_LOG | L_CONSOLE, "Can't fork");
+ _exit(1);
+ }
+
+ if (pid > 0) {
+
+ /* We are the parent -- wait till the child is done */
+ signal(SIGINT, SIG_IGN);
+ signal(SIGTSTP, SIG_IGN);
+ signal(SIGQUIT, SIG_IGN);
+ signal(SIGCHLD, SIG_DFL);
+
+ waitfor(NULL, pid);
+ /* See if stealing the controlling tty back is necessary */
+ if (tcgetpgrp(0) != getpid())
+ _exit(0);
+
+ /* Use a temporary process to steal the controlling tty. */
+ if ((pid = fork()) < 0) {
+ message(L_LOG | L_CONSOLE, "Can't fork");
+ _exit(1);
+ }
+ if (pid == 0) {
+ setsid();
+ ioctl(0, TIOCSCTTY, 1);
+ _exit(0);
+ }
+ waitfor(NULL, pid);
+ _exit(0);
+ }
+
+ /* Now fall though to actually execute things */
+ }
+
+ /* See if any special /bin/sh requiring characters are present */
+ if (strpbrk(a->command, "~`!$^&*()=|\\{}[];\"'<>?") != NULL) {
+ cmd[0] = (char*)DEFAULT_SHELL;
+ cmd[1] = (char*)"-c";
+ cmd[2] = strcat(strcpy(buf, "exec "), a->command);
+ cmd[3] = NULL;
+ } else {
+ /* Convert command (char*) into cmd (char**, one word per string) */
+ strcpy(buf, a->command);
+ s = buf;
+ for (tmpCmd = buf, i = 0; (tmpCmd = strsep(&s, " \t")) != NULL;) {
+ if (*tmpCmd != '\0') {
+ cmd[i] = tmpCmd;
+ i++;
+ }
+ }
+ cmd[i] = NULL;
+ }
+
+ cmdpath = cmd[0];
+
+ /*
+ * Interactive shells want to see a dash in argv[0]. This
+ * typically is handled by login, argv will be setup this
+ * way if a dash appears at the front of the command path
+ * (like "-/bin/sh").
+ */
+ if (*cmdpath == '-') {
+ /* skip over the dash */
+ ++cmdpath;
+
+ /* find the last component in the command pathname */
+ s = bb_get_last_path_component(cmdpath);
+
+ /* make a new argv[0] */
+ if ((cmd[0] = malloc(strlen(s) + 2)) == NULL) {
+ message(L_LOG | L_CONSOLE, bb_msg_memory_exhausted);
+ cmd[0] = cmdpath;
+ } else {
+ cmd[0][0] = '-';
+ strcpy(cmd[0] + 1, s);
+ }
+#if ENABLE_FEATURE_INIT_SCTTY
+ /* Establish this process as session leader and
+ * (attempt) to make the tty (if any) a controlling tty.
+ */
+ setsid();
+ ioctl(0, TIOCSCTTY, 0 /*don't steal it*/);
+#endif
+ }
+
+#if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
+ if (a->action & ASKFIRST) {
+ static const char press_enter[] =
+#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",
+ cmdpath, getpid(), a->terminal);
+ full_write(1, press_enter, sizeof(press_enter) - 1);
+ while (read(0, &c, 1) == 1 && c != '\n')
+ ;
+ }
+#endif
+ /* Log the process name and args */
+ message(L_LOG, "starting pid %d, tty '%s': '%s'",
+ getpid(), a->terminal, cmdpath);
+
+#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);
+ }
+ }
+#endif
+ /* Now run it. The new program will take over this PID,
+ * so nothing further in init.c should be run. */
+ BB_EXECVP(cmdpath, cmd);
+
+ /* We're still here? Some error happened. */
+ message(L_LOG | L_CONSOLE, "Cannot run '%s': %s",
+ cmdpath, strerror(errno));
+ _exit(-1);
+}
+
+static int waitfor(const struct init_action *a, pid_t pid)
+{
+ int runpid;
+ int status, wpid;
+
+ runpid = (NULL == a)? pid : run(a);
+ while (1) {
+ wpid = waitpid(runpid, &status, 0);
+ if (wpid == runpid)
+ break;
+ if (wpid == -1 && errno == ECHILD) {
+ /* we missed its termination */
+ break;
+ }
+ /* FIXME other errors should maybe trigger an error, but allow
+ * the program to continue */
+ }
+ return wpid;
+}
+
+/* Run all commands of a particular type */
+static void run_actions(int action)
+{
+ struct init_action *a, *tmp;
+
+ for (a = init_action_list; a; a = tmp) {
+ tmp = a->next;
+ if (a->action == action) {
+ /* a->terminal of "" means "init's console" */
+ if (a->terminal[0] && access(a->terminal, R_OK | W_OK)) {
+ delete_init_action(a);
+ } else if (a->action & (SYSINIT | WAIT | CTRLALTDEL | SHUTDOWN | RESTART)) {
+ waitfor(a, 0);
+ delete_init_action(a);
+ } else if (a->action & ONCE) {
+ run(a);
+ delete_init_action(a);
+ } else if (a->action & (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);
+ }
+ }
+ }
+ }
+}
+
+#if !ENABLE_DEBUG_INIT
+static void init_reboot(unsigned long magic)
+{
+ pid_t pid;
+ /* We have to fork here, since the kernel calls do_exit(0) 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(0);
+ }
+ waitpid(pid, NULL, 0);
+}
+
+static void shutdown_system(void)
+{
+ sigset_t block_signals;
+
+ /* 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 */
+ sigemptyset(&block_signals);
+ sigaddset(&block_signals, SIGHUP);
+ sigaddset(&block_signals, SIGQUIT);
+ sigaddset(&block_signals, SIGCHLD);
+ sigaddset(&block_signals, SIGUSR1);
+ sigaddset(&block_signals, SIGUSR2);
+ sigaddset(&block_signals, SIGINT);
+ sigaddset(&block_signals, SIGTERM);
+ sigaddset(&block_signals, SIGCONT);
+ sigaddset(&block_signals, SIGSTOP);
+ sigaddset(&block_signals, SIGTSTP);
+ sigprocmask(SIG_BLOCK, &block_signals, NULL);
+
+ 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 exec_signal(int sig ATTRIBUTE_UNUSED)
+{
+ struct init_action *a, *tmp;
+ sigset_t unblock_signals;
+
+ for (a = init_action_list; a; a = tmp) {
+ tmp = a->next;
+ if (a->action & RESTART) {
+ shutdown_system();
+
+ /* unblock all signals, blocked in shutdown_system() */
+ sigemptyset(&unblock_signals);
+ sigaddset(&unblock_signals, SIGHUP);
+ sigaddset(&unblock_signals, SIGQUIT);
+ sigaddset(&unblock_signals, SIGCHLD);
+ sigaddset(&unblock_signals, SIGUSR1);
+ sigaddset(&unblock_signals, SIGUSR2);
+ sigaddset(&unblock_signals, SIGINT);
+ sigaddset(&unblock_signals, SIGTERM);
+ sigaddset(&unblock_signals, SIGCONT);
+ sigaddset(&unblock_signals, SIGSTOP);
+ sigaddset(&unblock_signals, SIGTSTP);
+ sigprocmask(SIG_UNBLOCK, &unblock_signals, NULL);
+
+ /* Open the new terminal device */
+ open_stdio_to_tty(a->terminal, 0);
+
+ messageD(L_CONSOLE | L_LOG, "Trying to re-exec %s", a->command);
+ BB_EXECLP(a->command, a->command, NULL);
+
+ message(L_CONSOLE | L_LOG, "Cannot run '%s': %s",
+ a->command, strerror(errno));
+ sleep(2);
+ init_reboot(RB_HALT_SYSTEM);
+ loop_forever();
+ }
+ }
+}
+
+static void shutdown_signal(int sig)
+{
+ const char *m;
+ int rb;
+
+ shutdown_system();
+
+ m = "halt";
+ 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();
+}
+
+static void ctrlaltdel_signal(int sig ATTRIBUTE_UNUSED)
+{
+ run_actions(CTRLALTDEL);
+}
+
+/* The SIGSTOP & SIGTSTP handler */
+static void stop_handler(int sig ATTRIBUTE_UNUSED)
+{
+ int saved_errno = errno;
+
+ got_cont = 0;
+ while (!got_cont)
+ pause();
+ got_cont = 0;
+ errno = saved_errno;
+}
+
+/* The SIGCONT handler */
+static void cont_handler(int sig ATTRIBUTE_UNUSED)
+{
+ got_cont = 1;
+}
+
+#endif /* !ENABLE_DEBUG_INIT */
+
+static void new_init_action(int action, const char *command, const char *cons)
+{
+ struct init_action *new_action, *a, *last;
+
+ 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 = action;
+ return;
+ }
+ last = a;
+ }
+
+ new_action = xzalloc(sizeof(struct init_action));
+ if (last) {
+ last->next = new_action;
+ } else {
+ init_action_list = new_action;
+ }
+ strcpy(new_action->command, command);
+ new_action->action = action;
+ strcpy(new_action->terminal, cons);
+ messageD(L_LOG | L_CONSOLE, "command='%s' action=%d tty='%s'\n",
+ new_action->command, new_action->action, new_action->terminal);
+}
+
+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;
+ }
+ }
+}
+
+/* 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
+ FILE *file;
+ char buf[INIT_BUFFS_SIZE], lineAsRead[INIT_BUFFS_SIZE];
+ char tmpConsole[CONSOLE_NAME_SIZE];
+ char *id, *runlev, *action, *command, *eol;
+ const struct init_action_type *a = actions;
+
+ file = fopen(INITTAB, "r");
+ if (file == NULL) {
+ /* No inittab file -- set up some default behavior */
+#endif
+ /* 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 HUP is received */
+ new_init_action(RESTART, "init", "");
+ /* Askfirst shell on tty1-4 */
+ new_init_action(ASKFIRST, bb_default_login_shell, "");
+ 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
+ }
+
+ while (fgets(buf, INIT_BUFFS_SIZE, file) != NULL) {
+ /* Skip leading spaces */
+ for (id = buf; *id == ' ' || *id == '\t'; id++);
+
+ /* Skip the line if it's a comment */
+ if (*id == '#' || *id == '\n')
+ continue;
+
+ /* Trim the trailing \n */
+ //XXX: chomp() ?
+ eol = strrchr(id, '\n');
+ if (eol != NULL)
+ *eol = '\0';
+
+ /* Keep a copy around for posterity's sake (and error msgs) */
+ strcpy(lineAsRead, buf);
+
+ /* Separate the ID field from the runlevels */
+ runlev = strchr(id, ':');
+ if (runlev == NULL || *(runlev + 1) == '\0') {
+ message(L_LOG | L_CONSOLE, "Bad inittab entry: %s", lineAsRead);
+ continue;
+ } else {
+ *runlev = '\0';
+ ++runlev;
+ }
+
+ /* Separate the runlevels from the action */
+ action = strchr(runlev, ':');
+ if (action == NULL || *(action + 1) == '\0') {
+ message(L_LOG | L_CONSOLE, "Bad inittab entry: %s", lineAsRead);
+ continue;
+ } else {
+ *action = '\0';
+ ++action;
+ }
+
+ /* Separate the action from the command */
+ command = strchr(action, ':');
+ if (command == NULL || *(command + 1) == '\0') {
+ message(L_LOG | L_CONSOLE, "Bad inittab entry: %s", lineAsRead);
+ continue;
+ } else {
+ *command = '\0';
+ ++command;
+ }
+
+ /* Ok, now process it */
+ for (a = actions; a->name != 0; a++) {
+ if (strcmp(a->name, action) == 0) {
+ if (*id != '\0') {
+ if(strncmp(id, "/dev/", 5) == 0)
+ id += 5;
+ strcpy(tmpConsole, "/dev/");
+ safe_strncpy(tmpConsole + 5, id,
+ sizeof(tmpConsole) - 5);
+ id = tmpConsole;
+ }
+ new_init_action(a->action, command, id);
+ break;
+ }
+ }
+ if (a->name == 0) {
+ /* Choke on an unknown action */
+ message(L_LOG | L_CONSOLE, "Bad inittab entry: %s", lineAsRead);
+ }
+ }
+ fclose(file);
+#endif /* FEATURE_USE_INITTAB */
+}
+
+#if ENABLE_FEATURE_USE_INITTAB
+static void reload_signal(int sig ATTRIBUTE_UNUSED)
+{
+ 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 = ONCE;
+ }
+
+ parse_inittab();
+
+ /* remove unused entrys */
+ for (a = init_action_list; a; a = tmp) {
+ tmp = a->next;
+ if (a->action & (ONCE | SYSINIT | WAIT ) &&
+ a->pid == 0 ) {
+ delete_init_action(a);
+ }
+ }
+ run_actions(RESPAWN);
+}
+#endif /* FEATURE_USE_INITTAB */
+
+int init_main(int argc, char **argv);
+int init_main(int argc, char **argv)
+{
+ struct init_action *a;
+ pid_t wpid;
+
+ die_sleep = 30 * 24*60*60; /* if xmalloc will ever die... */
+
+ if (argc > 1 && !strcmp(argv[1], "-q")) {
+ return kill(1, SIGHUP);
+ }
+#if !ENABLE_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(SIGHUP, exec_signal);
+ signal(SIGQUIT, exec_signal);
+ signal(SIGUSR1, shutdown_signal);
+ signal(SIGUSR2, shutdown_signal);
+ signal(SIGINT, ctrlaltdel_signal);
+ signal(SIGTERM, shutdown_signal);
+ signal(SIGCONT, cont_handler);
+ signal(SIGSTOP, stop_handler);
+ signal(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);
+#endif
+
+ /* Figure out where the default console should be */
+ console_init();
+ set_sane_term();
+ chdir("/");
+ setsid();
+ {
+ const char * const *e;
+ /* Make sure environs is set to something sane */
+ for (e = environment; *e; e++)
+ putenv((char *) *e);
+ }
+
+ if (argc > 1) setenv("RUNLEVEL", argv[1], 1);
+
+ /* Hello world */
+ message(MAYBE_CONSOLE | L_LOG, "init started: %s", bb_msg_full_version);
+
+ /* 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 (argc > 1
+ && (!strcmp(argv[1], "single") || !strcmp(argv[1], "-s") || LONE_CHAR(argv[1], '1'))
+ ) {
+ /* 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("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 */
+ /* At this point, we probably can't open /dev/console, so log() won't work */
+ message(L_CONSOLE, "Cannot load SELinux Policy. "
+ "Machine is in enforcing mode. Halting now.");
+ exit(1);
+ }
+ }
+#endif /* CONFIG_SELINUX */
+
+ /* Make the command line just say "init" -- thats all, nothing else */
+ fixup_argv(argc, argv, "init");
+
+ /* 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);
+
+#if ENABLE_FEATURE_USE_INITTAB
+ /* Redefine SIGHUP to reread /etc/inittab */
+ signal(SIGHUP, reload_signal);
+#else
+ signal(SIGHUP, SIG_IGN);
+#endif /* FEATURE_USE_INITTAB */
+
+ /* Now run the looping stuff for the rest of forever */
+ while (1) {
+ /* run the respawn stuff */
+ run_actions(RESPAWN);
+
+ /* run the askfirst stuff */
+ run_actions(ASKFIRST);
+
+ /* Don't consume all CPU time -- sleep a bit */
+ sleep(1);
+
+ /* Wait for a 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 it for restart.",
+ a->command, wpid);
+ }
+ }
+ /* see if anyone else is waiting to be reaped */
+ wpid = waitpid(-1, NULL, WNOHANG);
+ }
+ }
+}