basename/basename.c

   1 /*      $NetBSD: basename.c,v 1.10 1997/10/18 12:18:20 lukem Exp $      */
   2
   3 /*-
   4  * Copyright (c) 1991, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include <sys/cdefs.h>
  37 #ifndef lint
  38 __COPYRIGHT("@(#) Copyright (c) 1991, 1993, 1994\n\
  39         The Regents of the University of California.  All rights reserved.\n");
  40 #endif /* not lint */
  41
  42 #ifndef lint
  43 #if 0
  44 static char sccsid[] = "@(#)basename.c  8.4 (Berkeley) 5/4/95";
  45 #endif
  46 __RCSID("$NetBSD: basename.c,v 1.10 1997/10/18 12:18:20 lukem Exp $");
  47 #endif /* not lint */
  48
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52 #include <locale.h>
  53 #include <unistd.h>
  54
  55 int main __P((int, char **));
  56 void usage __P((void));
  57
  58 int
  59 main(argc, argv)
  60         int argc;
  61         char **argv;
  62 {
  63         char *p;
  64         int ch;
  65
  66         setlocale(LC_ALL, "");
  67
  68         while ((ch = getopt(argc, argv, "")) != -1)
  69                 switch(ch) {
  70                 case '?':
  71                 default:
  72                         usage();
  73                 }
  74         argc -= optind;
  75         argv += optind;
  76
  77         if (argc != 1 && argc != 2)
  78                 usage();
  79
  80         /*
  81          * (1) If string is // it is implementation defined whether steps (2)
  82          *     through (5) are skipped or processed.
  83          *
  84          * (2) If string consists entirely of slash characters, string shall
  85          *     be set to a single slash character.  In this case, skip steps
  86          *     (3) through (5).
  87          */
  88         for (p = *argv;; ++p) {
  89                 if (!*p) {
  90                         if (p > *argv)
  91                                 (void)printf("/\n");
  92                         else
  93                                 (void)printf("\n");
  94                         exit(0);
  95                 }
  96                 if (*p != '/')
  97                         break;
  98         }
  99
 100         /*
 101          * (3) If there are any trailing slash characters in string, they
 102          *     shall be removed.
 103          */
 104         for (; *p; ++p)
 105                 continue;
 106         while (*--p == '/')
 107                 continue;
 108         *++p = '\0';
 109
 110         /*
 111          * (4) If there are any slash characters remaining in string, the
 112          *     prefix of string up to an including the last slash character
 113          *     in string shall be removed.
 114          */
 115         while (--p >= *argv)
 116                 if (*p == '/')
 117                         break;
 118         ++p;
 119
 120         /*
 121          * (5) If the suffix operand is present, is not identical to the
 122          *     characters remaining in string, and is identical to a suffix
 123          *     of the characters remaining in string, the suffix suffix
 124          *     shall be removed from string.
 125          */
 126         if (*++argv) {
 127                 int suffixlen, stringlen, off;
 128
 129                 suffixlen = strlen(*argv);
 130                 stringlen = strlen(p);
 131
 132                 if (suffixlen < stringlen) {
 133                         off = stringlen - suffixlen;
 134                         if (!strcmp(p + off, *argv))
 135                                 p[off] = '\0';
 136                 }
 137         }
 138         (void)printf("%s\n", p);
 139         exit(0);
 140 }
 141
 142 void
 143 usage()
 144 {
 145
 146         (void)fprintf(stderr, "usage: basename string [suffix]\n");
 147         exit(1);
 148 }