sys-utils/ctrlaltdel.c

   1 /*
   2  * ctrlaltdel.c - Set the function of the Ctrl-Alt-Del combination
   3  * Created 4-Jul-92 by Peter Orbaek <poe@daimi.aau.dk>
   4  * 1999-02-22 Arkadiusz Miśkiewicz <misiek@pld.ORG.PL>
   5  * - added Native Language Support
   6  */
   7
   8 #include <getopt.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <errno.h>
  13 #include <unistd.h>
  14 #include <sys/reboot.h>
  15 #include "nls.h"
  16 #include "c.h"
  17 #include "closestream.h"
  18 #include "pathnames.h"
  19 #include "path.h"
  20
  21 #define LINUX_REBOOT_CMD_CAD_ON 0x89ABCDEF
  22 #define LINUX_REBOOT_CMD_CAD_OFF 0x00000000
  23
  24 static void __attribute__ ((__noreturn__)) usage(FILE * out)
  25 {
  26         fprintf(out, USAGE_HEADER);
  27         fprintf(out, _(" %s hard|soft\n"), program_invocation_short_name);
  28
  29         fprintf(out, USAGE_SEPARATOR);
  30         fprintf(out, _("Set the function of the Ctrl-Alt-Del combination.\n"));
  31
  32         fprintf(out, USAGE_OPTIONS);
  33         fprintf(out, USAGE_HELP);
  34         fprintf(out, USAGE_VERSION);
  35         fprintf(out, USAGE_MAN_TAIL("ctrlaltdel(8)"));
  36         exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
  37 }
  38
  39 static int get_cad(void)
  40 {
  41         uint64_t val = path_read_u64(_PATH_PROC_CTRL_ALT_DEL);
  42
  43         switch (val) {
  44         case 0:
  45                 fputs("soft\n", stdout);
  46                 break;
  47         case 1:
  48                 fputs("hard\n", stdout);
  49                 break;
  50         default:
  51                 printf("%s hard\n", _("implicit"));
  52                 warnx(_("unexpected value in %s: %ju"), _PATH_PROC_CTRL_ALT_DEL, val);
  53                 return EXIT_FAILURE;
  54         }
  55         return EXIT_SUCCESS;
  56 }
  57
  58 static int set_cad(const char *arg)
  59 {
  60         unsigned int cmd;
  61
  62         if (geteuid()) {
  63                 warnx(_("You must be root to set the Ctrl-Alt-Del behavior"));
  64                 return EXIT_FAILURE;
  65         }
  66         if (!strcmp("hard", arg))
  67                 cmd = LINUX_REBOOT_CMD_CAD_ON;
  68         else if (!strcmp("soft", arg))
  69                 cmd = LINUX_REBOOT_CMD_CAD_OFF;
  70         else {
  71                 warnx(_("unknown argument: %s"), arg);
  72                 return EXIT_FAILURE;
  73         }
  74         if (reboot(cmd) < 0) {
  75                 warnx("reboot");
  76                 return EXIT_FAILURE;
  77         }
  78         return EXIT_SUCCESS;
  79 }
  80
  81 int main(int argc, char **argv)
  82 {
  83         int ch, ret;
  84         static const struct option longopts[] = {
  85                 {"version", no_argument, NULL, 'V'},
  86                 {"help", no_argument, NULL, 'h'},
  87                 {NULL, 0, NULL, 0}
  88         };
  89
  90         setlocale(LC_ALL, "");
  91         bindtextdomain(PACKAGE, LOCALEDIR);
  92         textdomain(PACKAGE);
  93         atexit(close_stdout);
  94
  95         while ((ch = getopt_long(argc, argv, "Vh", longopts, NULL)) != -1)
  96                 switch (ch) {
  97                 case 'V':
  98                         printf(UTIL_LINUX_VERSION);
  99                         return EXIT_SUCCESS;
 100                 case 'h':
 101                         usage(stdout);
 102                 default:
 103                         errtryhelp(EXIT_FAILURE);
 104                 }
 105
 106         if (argc < 2)
 107                 ret = get_cad();
 108         else
 109                 ret = set_cad(argv[1]);
 110         return ret;
 111 }