lib/libc/gen/basename.c

   1 /*      $NetBSD: basename.c,v 1.11 2014/07/16 10:52:26 christos 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 #include <sys/cdefs.h>
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 __RCSID("$NetBSD: basename.c,v 1.11 2014/07/16 10:52:26 christos Exp $");
  35 #endif /* !LIBC_SCCS && !lint */
  36
  37 #include "namespace.h"
  38 #include <sys/param.h>
  39 #include <libgen.h>
  40 #include <string.h>
  41 #include <limits.h>
  42 #include <string.h>
  43
  44 #ifdef __weak_alias
  45 __weak_alias(basename,_basename)
  46 #endif
  47
  48 static size_t
  49 xbasename_r(const char *path, char *buf, size_t buflen)
  50 {
  51         const char *startp, *endp;
  52         size_t len;
  53
  54         /*
  55          * If `path' is a null pointer or points to an empty string,
  56          * return a pointer to the string ".".
  57          */
  58         if (path == NULL || *path == '\0') {
  59                 startp = ".";
  60                 len = 1;
  61                 goto out;
  62         }
  63
  64         /* Strip trailing slashes, if any. */
  65         endp = path + strlen(path) - 1;
  66         while (endp != path && *endp == '/')
  67                 endp--;
  68
  69         /* Only slashes -> "/" */
  70         if (endp == path && *endp == '/') {
  71                 startp = "/";
  72                 len = 1;
  73                 goto out;
  74         }
  75
  76         /* Now find the beginning of this (final) component. */
  77         for (startp = endp; startp > path && *(startp - 1) != '/'; startp--)
  78                 continue;
  79
  80         /* ...and copy the result into the result buffer. */
  81         len = (endp - startp) + 1 /* last char */;
  82 out:
  83         if (buf != NULL && buflen != 0) {
  84                 buflen = MIN(len, buflen - 1);
  85                 memcpy(buf, startp, buflen);
  86                 buf[buflen] = '\0';
  87         }
  88         return len;
  89 }
  90
  91 #if !HAVE_BASENAME
  92
  93 char *
  94 basename(char *path) {
  95         static char result[PATH_MAX];
  96
  97         (void)xbasename_r(path, result, sizeof(result));
  98         return result;
  99 }
 100
 101 #endif