src/fgconsole.c

   1 /*
   2  * fgconsole.c - aeb - 960123 - Print foreground console
   3  */
   4 #include "config.h"
   5
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <errno.h>
   9 #include <sys/ioctl.h>
  10 #include <getopt.h>
  11 #include <sysexits.h>
  12 #include <linux/vt.h>
  13 #include <linux/serial.h>
  14
  15 #include "libcommon.h"
  16
  17 static void __attribute__((noreturn))
  18 usage(int rc)
  19 {
  20         const char *progname = get_progname();
  21         fprintf(stderr, _("%s version %s\n"
  22                           "\n"
  23                           "Usage: %s [options]\n"
  24                           "\n"
  25                           "Valid options are:\n"
  26                           "\n"
  27                           "     -h --help            display this help text\n"
  28                           "     -V --version         display program version\n"
  29                           "     -n --next-available  display number of next unallocated VT\n"),
  30                 progname, PACKAGE_VERSION, progname);
  31         exit(rc);
  32 }
  33
  34 int main(int argc, char **argv)
  35 {
  36         struct vt_stat vtstat;
  37         int fd, vtno = -1, c, show_vt = 0;
  38         struct serial_struct sr;
  39         const struct option long_opts[] = {
  40                 { "help", no_argument, NULL, 'h' },
  41                 { "version", no_argument, NULL, 'V' },
  42                 { "next-available", no_argument, NULL, 'n' },
  43                 { NULL, 0, NULL, 0 }
  44         };
  45
  46         set_progname(argv[0]);
  47         setuplocale();
  48
  49         while ((c = getopt_long(argc, argv, "Vhn", long_opts, NULL)) != EOF) {
  50                 switch (c) {
  51                         case 'n':
  52                                 show_vt = 1;
  53                                 break;
  54                         case 'V':
  55                                 print_version_and_exit();
  56                                 break;
  57                         case 'h':
  58                                 usage(EXIT_SUCCESS);
  59                                 break;
  60                         case '?':
  61                                 usage(EX_USAGE);
  62                                 break;
  63                 }
  64         }
  65
  66         if ((fd = getfd(NULL)) < 0)
  67                 kbd_error(EXIT_FAILURE, 0, _("Couldn't get a file descriptor referring to the console"));
  68
  69         if (show_vt) {
  70                 if ((ioctl(fd, VT_OPENQRY, &vtno) < 0) || vtno == -1) {
  71                         kbd_error(2, errno, _("Couldn't read VTNO: "));
  72                 }
  73                 printf("%d\n", vtno);
  74                 return EXIT_SUCCESS;
  75         }
  76
  77         if (ioctl(fd, TIOCGSERIAL, &sr) == 0) {
  78                 printf("serial\n");
  79                 return EXIT_SUCCESS;
  80         }
  81
  82         if (ioctl(fd, VT_GETSTATE, &vtstat)) {
  83                 kbd_error(EXIT_FAILURE, errno, "fgconsole: VT_GETSTATE");
  84         }
  85         printf("%d\n", vtstat.v_active);
  86         return EXIT_SUCCESS;
  87 }