src/mknod.c

   1 /* mknod -- make special files
   2    Copyright (C) 1990, 1991, 1995 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software
  16    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  17
  18 /* Usage: mknod [-m mode] [--mode=mode] path {bcu} major minor
  19                 make a block or character device node
  20           mknod [-m mode] [--mode=mode] path p
  21                 make a FIFO (named pipe)
  22
  23    Options:
  24    -m, --mode=mode      Set the mode of created nodes to MODE, which is
  25                         symbolic as in chmod and uses the umask as a point of
  26                         departure.
  27
  28    David MacKenzie <djm@ai.mit.edu>  */
  29
  30 #include <config.h>
  31 #include <stdio.h>
  32 #include <getopt.h>
  33 #include <sys/types.h>
  34
  35 #include "system.h"
  36 #include "modechange.h"
  37 #include "version.h"
  38 #include "error.h"
  39 #include "xstrtol.h"
  40
  41 /* The name this program was run with. */
  42 char *program_name;
  43
  44 /* If nonzero, display usage information and exit.  */
  45 static int show_help;
  46
  47 /* If nonzero, print the version on standard output and exit.  */
  48 static int show_version;
  49
  50 static struct option const longopts[] =
  51 {
  52   {"mode", required_argument, NULL, 'm'},
  53   {"help", no_argument, &show_help, 1},
  54   {"version", no_argument, &show_version, 1},
  55   {NULL, 0, NULL, 0}
  56 };
  57
  58 static void
  59 usage (int status)
  60 {
  61   if (status != 0)
  62     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  63              program_name);
  64   else
  65     {
  66       printf (_("Usage: %s [OPTION]... NAME TYPE [MAJOR MINOR]\n"), program_name);
  67       printf (_("\
  68 Create the special file NAME of the given TYPE.\n\
  69 \n\
  70   -m, --mode=MODE   set permission mode (as in chmod), not 0666 - umask\n\
  71       --help        display this help and exit\n\
  72       --version     output version information and exit\n\
  73 \n\
  74 MAJOR MINOR are forbidden for TYPE p, mandatory otherwise.  TYPE may be:\n\
  75 \n\
  76   b      create a block (buffered) special file\n\
  77   c, u   create a character (unbuffered) special file   \n\
  78   p      create a FIFO\n"));
  79     }
  80   exit (status);
  81 }
  82
  83 void
  84 main (int argc, char **argv)
  85 {
  86   unsigned short newmode;
  87   struct mode_change *change;
  88   char *symbolic_mode;
  89   int optc;
  90   int i_major, i_minor;
  91   long int tmp_major, tmp_minor;
  92   char *s;
  93
  94   program_name = argv[0];
  95   symbolic_mode = NULL;
  96
  97   while ((optc = getopt_long (argc, argv, "m:", longopts, (int *) 0)) != EOF)
  98     {
  99       switch (optc)
 100         {
 101         case 0:
 102           break;
 103         case 'm':
 104           symbolic_mode = optarg;
 105           break;
 106         default:
 107           usage (1);
 108         }
 109     }
 110
 111   if (show_version)
 112     {
 113       printf ("mknod - %s\n", version_string);
 114       exit (0);
 115     }
 116
 117   if (show_help)
 118     usage (0);
 119
 120   newmode = 0666 & ~umask (0);
 121   if (symbolic_mode)
 122     {
 123       change = mode_compile (symbolic_mode, 0);
 124       if (change == MODE_INVALID)
 125         error (1, 0, _("invalid mode"));
 126       else if (change == MODE_MEMORY_EXHAUSTED)
 127         error (1, 0, _("virtual memory exhausted"));
 128       newmode = mode_adjust (newmode, change);
 129     }
 130
 131   if (argc - optind != 2 && argc - optind != 4)
 132     {
 133       const char *msg;
 134       if (argc - optind < 2)
 135         msg = _("too few arguments");
 136       else if (argc - optind > 4)
 137         msg = _("too many arguments");
 138       else
 139         msg = _("wrong number of arguments");
 140       error (0, 0, msg);
 141       usage (1);
 142     }
 143
 144   /* Only check the first character, to allow mnemonic usage like
 145      `mknod /dev/rst0 character 18 0'. */
 146
 147   switch (argv[optind + 1][0])
 148     {
 149     case 'b':                   /* `block' or `buffered' */
 150 #ifndef S_IFBLK
 151       error (4, 0, _("block special files not supported"));
 152 #else
 153       if (argc - optind != 4)
 154         {
 155           error (0, 0, _("\
 156 when creating block special files, major and minor device\n\
 157 numbers must be specified"));
 158           usage (1);
 159         }
 160
 161       s = argv[optind + 2];
 162       if (xstrtol (s, NULL, 0, &tmp_major, NULL) != LONGINT_OK)
 163         error (1, 0, _("invalid major device number `%s'"), s);
 164
 165       s = argv[optind + 3];
 166       if (xstrtol (s, NULL, 0, &tmp_minor, NULL) != LONGINT_OK)
 167         error (1, 0, _("invalid minor device number `%s'"), s);
 168
 169       i_major = (int) tmp_major;
 170       i_minor = (int) tmp_minor;
 171
 172       if (mknod (argv[optind], newmode | S_IFBLK, makedev (i_major, i_minor)))
 173         error (1, errno, "%s", argv[optind]);
 174 #endif
 175       break;
 176
 177     case 'c':                   /* `character' */
 178     case 'u':                   /* `unbuffered' */
 179 #ifndef S_IFCHR
 180       error (4, 0, _("character special files not supported"));
 181 #else
 182       if (argc - optind != 4)
 183         {
 184           error (0, 0, _("\
 185 when creating character special files, major and minor device\n\
 186 numbers must be specified"));
 187           usage (1);
 188         }
 189
 190       s = argv[optind + 2];
 191       if (xstrtol (s, NULL, 0, &tmp_major, NULL) != LONGINT_OK)
 192         error (1, 0, _("invalid major device number `%s'"), s);
 193
 194       s = argv[optind + 3];
 195       if (xstrtol (s, NULL, 0, &tmp_minor, NULL) != LONGINT_OK)
 196         error (1, 0, _("invalid minor device number `%s'"), s);
 197
 198       i_major = (int) tmp_major;
 199       i_minor = (int) tmp_minor;
 200
 201       if (mknod (argv[optind], newmode | S_IFCHR, makedev (i_major, i_minor)))
 202         error (1, errno, "%s", argv[optind]);
 203 #endif
 204       break;
 205
 206     case 'p':                   /* `pipe' */
 207 #ifndef S_ISFIFO
 208       error (4, 0, _("fifo files not supported"));
 209 #else
 210       if (argc - optind != 2)
 211         {
 212           error (0, 0, _("\
 213 major and minor device numbers may not be specified for fifo files"));
 214           usage (1);
 215         }
 216       if (mkfifo (argv[optind], newmode))
 217         error (1, errno, "%s", argv[optind]);
 218 #endif
 219       break;
 220
 221     default:
 222       usage (1);
 223     }
 224
 225   exit (0);
 226 }