init/halt.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Poweroff reboot and halt, oh my.
   4  *
   5  * Copyright 2006 by Rob Landley <rob@landley.net>
   6  *
   7  * Licensed under GPL version 2, see file LICENSE in this tarball for details.
   8  */
   9
  10 #include "libbb.h"
  11 #include <sys/reboot.h>
  12
  13 #if ENABLE_FEATURE_WTMP
  14 #include <sys/utsname.h>
  15 #include <utmp.h>
  16
  17 static void write_wtmp(void)
  18 {
  19         struct utmp utmp;
  20         struct utsname uts;
  21         if (access(bb_path_wtmp_file, R_OK|W_OK) == -1) {
  22                 close(creat(bb_path_wtmp_file, 0664));
  23         }
  24         memset(&utmp, 0, sizeof(utmp));
  25         utmp.ut_tv.tv_sec = time(NULL);
  26         safe_strncpy(utmp.ut_user, "shutdown", UT_NAMESIZE);
  27         utmp.ut_type = RUN_LVL;
  28         safe_strncpy(utmp.ut_id, "~~", sizeof(utmp.ut_id));
  29         safe_strncpy(utmp.ut_line, "~~", UT_LINESIZE);
  30         if (uname(&uts) == 0)
  31                 safe_strncpy(utmp.ut_host, uts.release, sizeof(utmp.ut_host));
  32         updwtmp(bb_path_wtmp_file, &utmp);
  33
  34 }
  35 #else
  36 #define write_wtmp() ((void)0)
  37 #endif
  38
  39 #ifndef RB_HALT_SYSTEM
  40 #define RB_HALT_SYSTEM RB_HALT
  41 #endif
  42
  43 #ifndef RB_POWER_OFF
  44 #define RB_POWER_OFF RB_POWERDOWN
  45 #endif
  46
  47 int halt_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  48 int halt_main(int argc UNUSED_PARAM, char **argv)
  49 {
  50         static const int magic[] = {
  51                 RB_HALT_SYSTEM,
  52                 RB_POWER_OFF,
  53                 RB_AUTOBOOT
  54         };
  55         static const smallint signals[] = { SIGUSR1, SIGUSR2, SIGTERM };
  56
  57         int delay = 0;
  58         int which, flags, rc;
  59
  60         /* Figure out which applet we're running */
  61         for (which = 0; "hpr"[which] != applet_name[0]; which++)
  62                 continue;
  63
  64         /* Parse and handle arguments */
  65         opt_complementary = "d+"; /* -d N */
  66         /* We support -w even if !ENABLE_FEATURE_WTMP,
  67          * in order to not break scripts.
  68          * -i (shut down network interfaces) is ignored.
  69          */
  70         flags = getopt32(argv, "d:nfwi", &delay);
  71
  72         sleep(delay);
  73
  74         write_wtmp();
  75
  76         if (flags & 8) /* -w */
  77                 return EXIT_SUCCESS;
  78
  79         if (!(flags & 2)) /* no -n */
  80                 sync();
  81
  82         /* Perform action. */
  83         rc = 1;
  84         if (!(flags & 4)) { /* no -f */
  85 //TODO: I tend to think that signalling linuxrc is wrong
  86 // pity original author didn't comment on it...
  87                 if (ENABLE_FEATURE_INITRD) {
  88                         pid_t *pidlist = find_pid_by_name("linuxrc");
  89                         if (pidlist[0] > 0)
  90                                 rc = kill(pidlist[0], signals[which]);
  91                         if (ENABLE_FEATURE_CLEAN_UP)
  92                                 free(pidlist);
  93                 }
  94                 if (rc) {
  95                         rc = kill(1, signals[which]);
  96                 }
  97         } else {
  98                 rc = reboot(magic[which]);
  99         }
 100
 101         if (rc)
 102                 bb_perror_nomsg_and_die();
 103         return rc;
 104 }