contrib/bmake/dirname.c

   1 /*      $NetBSD: dirname.c,v 1.11 2009/11/24 13:34:20 tnozaki Exp $     */
   2
   3 /*-
   4  * Copyright (c) 1997, 2002 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Klaus Klein and Jason R. Thorpe.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #ifdef HAVE_CONFIG_H
  33 # include <config.h>
  34 #endif
  35 #ifndef HAVE_DIRNAME
  36
  37 #include <sys/cdefs.h>
  38
  39 #ifdef HAVE_LIMITS_H
  40 #include <limits.h>
  41 #endif
  42 #ifdef HAVE_STRING_H
  43 #include <string.h>
  44 #endif
  45 #ifndef PATH_MAX
  46 # define PATH_MAX 1024
  47 #endif
  48
  49 char *
  50 dirname(char *path)
  51 {
  52         static char result[PATH_MAX];
  53         const char *lastp;
  54         size_t len;
  55
  56         /*
  57          * If `path' is a null pointer or points to an empty string,
  58          * return a pointer to the string ".".
  59          */
  60         if ((path == NULL) || (*path == '\0'))
  61                 goto singledot;
  62
  63
  64         /* Strip trailing slashes, if any. */
  65         lastp = path + strlen(path) - 1;
  66         while (lastp != path && *lastp == '/')
  67                 lastp--;
  68
  69         /* Terminate path at the last occurence of '/'. */
  70         do {
  71                 if (*lastp == '/') {
  72                         /* Strip trailing slashes, if any. */
  73                         while (lastp != path && *lastp == '/')
  74                                 lastp--;
  75
  76                         /* ...and copy the result into the result buffer. */
  77                         len = (lastp - path) + 1 /* last char */;
  78                         if (len > (PATH_MAX - 1))
  79                                 len = PATH_MAX - 1;
  80
  81                         memcpy(result, path, len);
  82                         result[len] = '\0';
  83
  84                         return (result);
  85                 }
  86         } while (--lastp >= path);
  87
  88         /* No /'s found, return a pointer to the string ".". */
  89 singledot:
  90         result[0] = '.';
  91         result[1] = '\0';
  92
  93         return (result);
  94 }
  95 #endif