source: MondoRescue/branches/2.2.9/mindi-busybox/init/halt.c@ 2725

/* vi: set sw=4 ts=4: */
/*
 * Poweroff reboot and halt, oh my.
 *
 * Copyright 2006 by Rob Landley <rob@landley.net>
 *
 * Licensed under GPLv2, see file LICENSE in this source tree.
 */

//applet:IF_HALT(APPLET(halt, _BB_DIR_SBIN, _BB_SUID_DROP))
//applet:IF_HALT(APPLET_ODDNAME(poweroff, halt, _BB_DIR_SBIN, _BB_SUID_DROP, poweroff))
//applet:IF_HALT(APPLET_ODDNAME(reboot, halt, _BB_DIR_SBIN, _BB_SUID_DROP, reboot))

//kbuild:lib-$(CONFIG_HALT) += halt.o

//config:config HALT
//config:   bool "poweroff, halt, and reboot"
//config:   default y
//config:   help
//config:     Stop all processes and either halt, reboot, or power off the system.
//config:
//config:config FEATURE_CALL_TELINIT
//config:   bool "Call telinit on shutdown and reboot"
//config:   default y
//config:   depends on HALT && !INIT
//config:   help
//config:     Call an external program (normally telinit) to facilitate
//config:     a switch to a proper runlevel.
//config:
//config:     This option is only available if you selected halt and friends,
//config:     but did not select init.
//config:
//config:config TELINIT_PATH
//config:   string "Path to telinit executable"
//config:   default "/sbin/telinit"
//config:   depends on FEATURE_CALL_TELINIT
//config:   help
//config:     When busybox halt and friends have to call external telinit
//config:     to facilitate proper shutdown, this path is to be used when
//config:     locating telinit executable.

//usage:#define halt_trivial_usage
//usage:       "[-d DELAY] [-n] [-f]" IF_FEATURE_WTMP(" [-w]")
//usage:#define halt_full_usage "\n\n"
//usage:       "Halt the system\n"
//usage:     "\nOptions:"
//usage:     "\n    -d SEC  Delay interval"
//usage:     "\n    -n  Do not sync"
//usage:     "\n    -f  Force (don't go through init)"
//usage:    IF_FEATURE_WTMP(
//usage:     "\n    -w  Only write a wtmp record"
//usage:    )
//usage:
//usage:#define poweroff_trivial_usage
//usage:       "[-d DELAY] [-n] [-f]"
//usage:#define poweroff_full_usage "\n\n"
//usage:       "Halt and shut off power\n"
//usage:     "\nOptions:"
//usage:     "\n    -d SEC  Delay interval"
//usage:     "\n    -n  Do not sync"
//usage:     "\n    -f  Force (don't go through init)"
//usage:
//usage:#define reboot_trivial_usage
//usage:       "[-d DELAY] [-n] [-f]"
//usage:#define reboot_full_usage "\n\n"
//usage:       "Reboot the system\n"
//usage:     "\nOptions:"
//usage:     "\n    -d SEC  Delay interval"
//usage:     "\n    -n  Do not sync"
//usage:     "\n    -f  Force (don't go through init)"

#include "libbb.h"
#include "reboot.h"

#if ENABLE_FEATURE_WTMP
#include <sys/utsname.h>
#include <utmp.h>

static void write_wtmp(void)
{
    struct utmp utmp;
    struct utsname uts;
    /* "man utmp" says wtmp file should *not* be created automagically */
    /*if (access(bb_path_wtmp_file, R_OK|W_OK) == -1) {
        close(creat(bb_path_wtmp_file, 0664));
    }*/
    memset(&utmp, 0, sizeof(utmp));
    utmp.ut_tv.tv_sec = time(NULL);
    strcpy(utmp.ut_user, "shutdown"); /* it is wide enough */
    utmp.ut_type = RUN_LVL;
    utmp.ut_id[0] = '~'; utmp.ut_id[1] = '~'; /* = strcpy(utmp.ut_id, "~~"); */
    utmp.ut_line[0] = '~'; utmp.ut_line[1] = '~'; /* = strcpy(utmp.ut_line, "~~"); */
    uname(&uts);
    safe_strncpy(utmp.ut_host, uts.release, sizeof(utmp.ut_host));
    updwtmp(bb_path_wtmp_file, &utmp);
}
#else
#define write_wtmp() ((void)0)
#endif


int halt_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int halt_main(int argc UNUSED_PARAM, char **argv)
{
    static const int magic[] = {
        RB_HALT_SYSTEM,
        RB_POWER_OFF,
        RB_AUTOBOOT
    };
    static const smallint signals[] = { SIGUSR1, SIGUSR2, SIGTERM };

    int delay = 0;
    int which, flags, rc;

    /* Figure out which applet we're running */
    for (which = 0; "hpr"[which] != applet_name[0]; which++)
        continue;

    /* Parse and handle arguments */
    opt_complementary = "d+"; /* -d N */
    /* We support -w even if !ENABLE_FEATURE_WTMP,
     * in order to not break scripts.
     * -i (shut down network interfaces) is ignored.
     */
    flags = getopt32(argv, "d:nfwi", &delay);

    sleep(delay);

    write_wtmp();

    if (flags & 8) /* -w */
        return EXIT_SUCCESS;

    if (!(flags & 2)) /* no -n */
        sync();

    /* Perform action. */
    rc = 1;
    if (!(flags & 4)) { /* no -f */
//TODO: I tend to think that signalling linuxrc is wrong
// pity original author didn't comment on it...
        if (ENABLE_FEATURE_INITRD) {
            /* talk to linuxrc */
            /* bbox init/linuxrc assumed */
            pid_t *pidlist = find_pid_by_name("linuxrc");
            if (pidlist[0] > 0)
                rc = kill(pidlist[0], signals[which]);
            if (ENABLE_FEATURE_CLEAN_UP)
                free(pidlist);
        }
        if (rc) {
            /* talk to init */
            if (!ENABLE_FEATURE_CALL_TELINIT) {
                /* bbox init assumed */
                rc = kill(1, signals[which]);
            } else {
                /* SysV style init assumed */
                /* runlevels:
                 * 0 == shutdown
                 * 6 == reboot */
                rc = execlp(CONFIG_TELINIT_PATH,
                        CONFIG_TELINIT_PATH,
                        which == 2 ? "6" : "0",
                        (char *)NULL
                );
            }
        }
    } else {
        rc = reboot(magic[which]);
    }

    if (rc)
        bb_perror_nomsg_and_die();
    return rc;
}