login-utils/nologin.c

   1 /*
   2  * Copyright (C) 2013 Karel Zak <kzak@redhat.com>
   3  */
   4
   5 #include <stdio.h>
   6 #include <sys/types.h>
   7 #include <fcntl.h>
   8 #include <string.h>
   9 #include <unistd.h>
  10 #include <stdlib.h>
  11 #include <getopt.h>
  12
  13 #include "c.h"
  14 #include "nls.h"
  15 #include "pathnames.h"
  16
  17 /*
  18  * Always return EXIT_FAILURE (1), don't try to be smart!
  19  */
  20
  21 static void __attribute__((__noreturn__)) usage(FILE *out)
  22 {
  23         fputs(USAGE_HEADER, out);
  24         fprintf(out,
  25                 _(" %s [options]\n"), program_invocation_short_name);
  26
  27         fputs(USAGE_SEPARATOR, out);
  28         fputs(_("Politely refuse a login.\n"), out);
  29
  30         fputs(USAGE_OPTIONS, out);
  31         fputs(USAGE_HELP, out);
  32         fputs(USAGE_VERSION, out);
  33
  34         fprintf(out, USAGE_MAN_TAIL("nologin(8)"));
  35         exit(EXIT_FAILURE);
  36 }
  37
  38 int main(int argc, char *argv[])
  39 {
  40         int c, fd;
  41         static const struct option longopts[] = {
  42                 { "help",    0, 0, 'h' },
  43                 { "version", 0, 0, 'V' },
  44                 { NULL, 0, 0, 0 }
  45         };
  46
  47         setlocale(LC_ALL, "");
  48         bindtextdomain(PACKAGE, LOCALEDIR);
  49         textdomain(PACKAGE);
  50
  51         while ((c = getopt_long(argc, argv, "hV", longopts, NULL)) != -1) {
  52                 switch (c) {
  53                 case 'h':
  54                         usage(stdout);
  55                         break;
  56                 case 'V':
  57                         printf(UTIL_LINUX_VERSION);
  58                         return EXIT_FAILURE;
  59                 default:
  60                         usage(stderr);
  61                         break;
  62                 }
  63         }
  64
  65         fd = open(_PATH_NOLOGIN_TXT, O_RDONLY);
  66         if (fd >= 0) {
  67                 char buf[BUFSIZ];
  68                 ssize_t rd;
  69
  70                 while ((rd = read(fd, buf, sizeof(buf))) > 0)
  71                         ignore_result( write(STDOUT_FILENO, buf, rd) );
  72                 close(fd);
  73         } else
  74                 fprintf(stdout, _("This account is currently not available.\n"));
  75
  76         return EXIT_FAILURE;
  77 }