src/basename.c

   1 /* basename -- strip directory and suffix from file names
   2    Copyright (C) 1990-1997, 1999-2012 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 3 of the License, or
   7    (at your option) 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, see <http://www.gnu.org/licenses/>.  */
  16
  17 /* Usage: basename name [suffix]
  18    NAME is a file name; SUFFIX is a suffix to strip from it.
  19
  20    basename /usr/foo/lossage/functions.l
  21    => functions.l
  22    basename /usr/foo/lossage/functions.l .l
  23    => functions
  24    basename functions.lisp p
  25    => functions.lis */
  26
  27 #include <config.h>
  28 #include <getopt.h>
  29 #include <stdio.h>
  30 #include <sys/types.h>
  31
  32 #include "system.h"
  33 #include "long-options.h"
  34 #include "error.h"
  35 #include "quote.h"
  36
  37 /* The official name of this program (e.g., no `g' prefix).  */
  38 #define PROGRAM_NAME "basename"
  39
  40 #define AUTHORS proper_name ("David MacKenzie")
  41
  42 void
  43 usage (int status)
  44 {
  45   if (status != EXIT_SUCCESS)
  46     emit_try_help ();
  47   else
  48     {
  49       printf (_("\
  50 Usage: %s NAME [SUFFIX]\n\
  51   or:  %s OPTION\n\
  52 "),
  53               program_name, program_name);
  54       fputs (_("\
  55 Print NAME with any leading directory components removed.\n\
  56 If specified, also remove a trailing SUFFIX.\n\
  57 \n\
  58 "), stdout);
  59       fputs (HELP_OPTION_DESCRIPTION, stdout);
  60       fputs (VERSION_OPTION_DESCRIPTION, stdout);
  61       printf (_("\
  62 \n\
  63 Examples:\n\
  64   %s /usr/bin/sort       Output \"sort\".\n\
  65   %s include/stdio.h .h  Output \"stdio\".\n\
  66 "),
  67               program_name, program_name);
  68       emit_ancillary_info ();
  69     }
  70   exit (status);
  71 }
  72
  73 /* Remove SUFFIX from the end of NAME if it is there, unless NAME
  74    consists entirely of SUFFIX. */
  75
  76 static void
  77 remove_suffix (char *name, const char *suffix)
  78 {
  79   char *np;
  80   const char *sp;
  81
  82   np = name + strlen (name);
  83   sp = suffix + strlen (suffix);
  84
  85   while (np > name && sp > suffix)
  86     if (*--np != *--sp)
  87       return;
  88   if (np > name)
  89     *np = '\0';
  90 }
  91
  92 int
  93 main (int argc, char **argv)
  94 {
  95   char *name;
  96
  97   initialize_main (&argc, &argv);
  98   set_program_name (argv[0]);
  99   setlocale (LC_ALL, "");
 100   bindtextdomain (PACKAGE, LOCALEDIR);
 101   textdomain (PACKAGE);
 102
 103   atexit (close_stdout);
 104
 105   parse_long_options (argc, argv, PROGRAM_NAME, PACKAGE_NAME, Version,
 106                       usage, AUTHORS, (char const *) NULL);
 107   if (getopt_long (argc, argv, "+", NULL, NULL) != -1)
 108     usage (EXIT_FAILURE);
 109
 110   if (argc < optind + 1)
 111     {
 112       error (0, 0, _("missing operand"));
 113       usage (EXIT_FAILURE);
 114     }
 115
 116   if (optind + 2 < argc)
 117     {
 118       error (0, 0, _("extra operand %s"), quote (argv[optind + 2]));
 119       usage (EXIT_FAILURE);
 120     }
 121
 122   name = base_name (argv[optind]);
 123   strip_trailing_slashes (name);
 124
 125   /* Per POSIX, `basename // /' must return `//' on platforms with
 126      distinct //.  On platforms with drive letters, this generalizes
 127      to making `basename c: :' return `c:'.  This rule is captured by
 128      skipping suffix stripping if base_name returned an absolute path
 129      or a drive letter (only possible if name is a file-system
 130      root).  */
 131   if (argc == optind + 2 && IS_RELATIVE_FILE_NAME (name)
 132       && ! FILE_SYSTEM_PREFIX_LEN (name))
 133     remove_suffix (name, argv[optind + 1]);
 134
 135   puts (name);
 136   free (name);
 137
 138   exit (EXIT_SUCCESS);
 139 }