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 #include "wtmp.h"
  26
  27 void write_log( char *fn );
  28 void usage( void );
  29 int main( int argc, char *argv[] );
  30
  31 char *prog;
  32 char *reboot_code = "delay; boot";
  33
  34 void
  35 usage()
  36 {
  37   fprintf(stderr, "Usage: %s [-hrRfd] [-x reboot-code]\n", prog);
  38   exit(1);
  39 }
  40
  41 int
  42 main(argc,argv)
  43 int argc;
  44 char **argv;
  45 {
  46   int flag = -1;                /* default action unknown */
  47   int fast = 0;                 /* fast halt/reboot, don't bother being nice. */
  48   int i;
  49   struct stat dummy;
  50   char *monitor_code = "";
  51   pid_t pid;
  52
  53   if ((prog = strrchr(argv[0],'/')) == NULL) prog = argv[0]; else prog++;
  54
  55   if (strcmp(prog, "halt") == 0) flag = RBT_HALT;
  56   if (strcmp(prog, "reboot") == 0) flag = RBT_REBOOT;
  57
  58   i = 1;
  59   while (i < argc && argv[i][0] == '-') {
  60     char *opt = argv[i++] + 1;
  61
  62     if (*opt == '-' && opt[1] == 0) break;      /* -- */
  63
  64     while (*opt != 0) switch (*opt++) {
  65       case 'h': flag = RBT_HALT;        break;
  66       case 'r': flag = RBT_REBOOT;      break;
  67       case 'R': flag = RBT_RESET;       break;
  68       case 'd': flag = RBT_DEFAULT;     break;
  69       case 'f': fast = 1; break;
  70       case 'x':
  71         flag = RBT_MONITOR;
  72         if (*opt == 0) {
  73           if (i == argc) usage();
  74           opt = argv[i++];
  75         }
  76         monitor_code = opt;
  77         opt = "";
  78         break;
  79       default:
  80         usage();
  81     }
  82   }
  83
  84   if (i != argc) usage();
  85
  86   if (flag == -1) {
  87     fprintf(stderr, "Don't know what to do when named '%s'\n", prog);
  88     exit(1);
  89   }
  90
  91   if (flag == RBT_REBOOT) {
  92         flag = RBT_MONITOR;             /* set monitor code for reboot */
  93         monitor_code = reboot_code;
  94   }
  95
  96   if (stat("/usr/bin", &dummy) < 0) {
  97     /* It seems that /usr isn't present, let's assume "-f." */
  98     fast = 1;
  99   }
 100
 101   signal(SIGHUP, SIG_IGN);
 102   signal(SIGTERM, SIG_IGN);
 103
 104   /* Skip this part for fast shut down. */
 105   if (! fast) {
 106     /* Run the shutdown scripts. */
 107     switch ((pid = fork())) {
 108       case -1:
 109         fprintf(stderr, "%s: can't fork(): %s\n", prog, strerror(errno));
 110         exit(1);
 111       case 0:
 112         execl("/bin/sh", "sh", "/etc/rc", "down", (char *) NULL);
 113         fprintf(stderr, "%s: can't execute: /bin/sh: %s\n",
 114           prog, strerror(errno));
 115         exit(1);
 116       default:
 117         while (waitpid(pid, NULL, 0) != pid) {}
 118     }
 119   }
 120
 121   /* Tell init to stop spawning getty's. */
 122   kill(1, SIGTERM);
 123
 124   /* Extra sync for the case where SIGTERM causes deadlock */
 125   sync();
 126
 127   /* Give everybody a chance to die peacefully. */
 128   printf("Sending SIGTERM to all processes ...\n");
 129   kill(-1, SIGTERM);
 130   sleep(1);
 131
 132   write_log(STR_WTMP);
 133   write_log(STR_ROOT_WTMP);
 134
 135   sync();
 136
 137   reboot(flag, monitor_code, strlen(monitor_code));
 138   fprintf(stderr, "%s: reboot(): %s\n", prog, strerror(errno));
 139   return 1;
 140 }