LXR busybox/coreutils/basename.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * Mini basename implementation for busybox
   4 *
   5 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
   6 *
   7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8 */
   9
  10/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
  11 *
  12 * Changes:
  13 * 1) Now checks for too many args.  Need at least one and at most two.
  14 * 2) Don't check for options, as per SUSv3.
  15 * 3) Save some space by using strcmp().  Calling strncmp() here was silly.
  16 */
  17
  18/* BB_AUDIT SUSv3 compliant */
  19/* http://www.opengroup.org/onlinepubs/007904975/utilities/basename.html */
  20
  21//kbuild:lib-$(CONFIG_BASENAME) += basename.o
  22
  23//config:config BASENAME
  24//config:       bool "basename"
  25//config:       default y
  26//config:       help
  27//config:         basename is used to strip the directory and suffix from filenames,
  28//config:         leaving just the filename itself. Enable this option if you wish
  29//config:         to enable the 'basename' utility.
  30
  31//usage:#define basename_trivial_usage
  32//usage:       "FILE [SUFFIX]"
  33//usage:#define basename_full_usage "\n\n"
  34//usage:       "Strip directory path and .SUFFIX from FILE\n"
  35//usage:
  36//usage:#define basename_example_usage
  37//usage:       "$ basename /usr/local/bin/foo\n"
  38//usage:       "foo\n"
  39//usage:       "$ basename /usr/local/bin/\n"
  40//usage:       "bin\n"
  41//usage:       "$ basename /foo/bar.txt .txt\n"
  42//usage:       "bar"
  43
  44#include "libbb.h"
  45
  46/* This is a NOFORK applet. Be very careful! */
  47
  48int basename_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  49int basename_main(int argc, char **argv)
  50{
  51        size_t m, n;
  52        char *s;
  53
  54        if (argv[1] && strcmp(argv[1], "--") == 0) {
  55                argv++;
  56                argc--;
  57        }
  58
  59        if ((unsigned)(argc-2) >= 2) {
  60                bb_show_usage();
  61        }
  62
  63        /* It should strip slash: /abc/def/ -> def */
  64        s = bb_get_last_path_component_strip(*++argv);
  65
  66        m = strlen(s);
  67        if (*++argv) {
  68                n = strlen(*argv);
  69                if ((m > n) && (strcmp(s+m-n, *argv) == 0)) {
  70                        m -= n;
  71                        /*s[m] = '\0'; - redundant */
  72                }
  73        }
  74
  75        /* puts(s) will do, but we can do without stdio this way: */
  76        s[m++] = '\n';
  77        /* NB: != is correct here: */
  78        return full_write(STDOUT_FILENO, s, m) != (ssize_t)m;
  79}
  80