commands/reboot/halt.c

   1 /* halt / reboot - halt or reboot system (depends on name)
   2
   3    halt   - calling reboot() with RBT_HALT
   4    reboot - calling reboot() with RBT_REBOOT
   5
   6    author: Edvard Tuinder   v892231@si.hhs.NL
   7
   8    This program calls the library function reboot(2) which performs
   9    the system-call do_reboot.
  10
  11  */
  12
  13 #define _POSIX_SOURCE   1
  14 #include <sys/types.h>
  15 #include <fcntl.h>
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include <signal.h>
  19 #include <string.h>
  20 #include <errno.h>
  21 #include <unistd.h>
  22 #include <sys/stat.h>
  23 #include <sys/wait.h>
  24
  25 void write_log _ARGS(( void ));
  26 void usage _ARGS(( void ));
  27 int main _ARGS(( int argc, char *argv[] ));
  28
  29 char *prog;
  30 char *reboot_code = "delay; boot";
  31
  32 void
  33 usage()
  34 {
  35   fprintf(stderr, "Usage: %s [-hrRf] [-x reboot-code]\n", prog);
  36   exit(1);
  37 }
  38
  39 int
  40 main(argc,argv)
  41 int argc;
  42 char **argv;
  43 {
  44   int flag = -1;                /* default action unknown */
  45   int fast = 0;                 /* fast halt/reboot, don't bother being nice. */
  46   int i;
  47   struct stat dummy;
  48   char *monitor_code = "";
  49   pid_t pid;
  50
  51   if ((prog = strrchr(argv[0],'/')) == NULL) prog = argv[0]; else prog++;
  52
  53   if (strcmp(prog, "halt") == 0) flag = RBT_HALT;
  54   if (strcmp(prog, "reboot") == 0) flag = RBT_REBOOT;
  55
  56   i = 1;
  57   while (i < argc && argv[i][0] == '-') {
  58     char *opt = argv[i++] + 1;
  59
  60     if (*opt == '-' && opt[1] == 0) break;      /* -- */
  61
  62     while (*opt != 0) switch (*opt++) {
  63       case 'h': flag = RBT_HALT;        break;
  64       case 'r': flag = RBT_REBOOT;      break;
  65       case 'R': flag = RBT_RESET;       break;
  66       case 'f': fast = 1; break;
  67       case 'x':
  68         flag = RBT_MONITOR;
  69         if (*opt == 0) {
  70           if (i == argc) usage();
  71           opt = argv[i++];
  72         }
  73         monitor_code = opt;
  74         opt = "";
  75         break;
  76       default:
  77         usage();
  78     }
  79   }
  80
  81   if (i != argc) usage();
  82
  83   if (flag == -1) {
  84     fprintf(stderr, "Don't know what to do when named '%s'\n", prog);
  85     exit(1);
  86   }
  87
  88   if (flag == RBT_REBOOT) {
  89         flag = RBT_MONITOR;             /* set monitor code for reboot */
  90         monitor_code = reboot_code;
  91   }
  92
  93   if (stat("/usr/bin", &dummy) < 0) {
  94     /* It seems that /usr isn't present, let's assume "-f." */
  95     fast = 1;
  96   }
  97
  98   signal(SIGHUP, SIG_IGN);
  99   signal(SIGTERM, SIG_IGN);
 100
 101   /* Skip this part for fast shut down. */
 102   if (! fast) {
 103     /* Run the shutdown scripts. */
 104     switch ((pid = fork())) {
 105       case -1:
 106         fprintf(stderr, "%s: can't fork(): %s\n", prog, strerror(errno));
 107         exit(1);
 108       case 0:
 109         execl("/bin/sh", "sh", "/etc/rc", "down", (char *) NULL);
 110         fprintf(stderr, "%s: can't execute: /bin/sh: %s\n",
 111           prog, strerror(errno));
 112         exit(1);
 113       default:
 114         while (waitpid(pid, NULL, 0) != pid) {}
 115     }
 116   }
 117
 118   /* Tell init to stop spawning getty's. */
 119   kill(1, SIGTERM);
 120
 121   /* Give everybody a chance to die peacefully. */
 122   printf("Sending SIGTERM to all processes ...\n");
 123   kill(-1, SIGTERM);
 124   sleep(1);
 125
 126   write_log();
 127
 128   sync();
 129
 130   reboot(flag, monitor_code, strlen(monitor_code));
 131   fprintf(stderr, "%s: reboot(): %s\n", strerror(errno));
 132   return 1;
 133 }