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      1 /*	$OpenBSD: dirname.c,v 1.13 2005/08/08 08:05:33 espie Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1997, 2004 Todd C. Miller <Todd.Miller (at) courtesan.com>
      5  *
      6  * Permission to use, copy, modify, and distribute this software for any
      7  * purpose with or without fee is hereby granted, provided that the above
      8  * copyright notice and this permission notice appear in all copies.
      9  *
     10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
     11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
     12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
     13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
     14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
     15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
     16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
     17  */
     18 
     19 /* OPENBSD ORIGINAL: lib/libc/gen/dirname.c */
     20 
     21 #include "includes.h"
     22 #ifndef HAVE_DIRNAME
     23 
     24 #include <errno.h>
     25 #include <string.h>
     26 #include <sys/param.h>
     27 
     28 char *
     29 dirname(const char *path)
     30 {
     31 	static char dname[MAXPATHLEN];
     32 	size_t len;
     33 	const char *endp;
     34 
     35 	/* Empty or NULL string gets treated as "." */
     36 	if (path == NULL || *path == '\0') {
     37 		dname[0] = '.';
     38 		dname[1] = '\0';
     39 		return (dname);
     40 	}
     41 
     42 	/* Strip any trailing slashes */
     43 	endp = path + strlen(path) - 1;
     44 	while (endp > path && *endp == '/')
     45 		endp--;
     46 
     47 	/* Find the start of the dir */
     48 	while (endp > path && *endp != '/')
     49 		endp--;
     50 
     51 	/* Either the dir is "/" or there are no slashes */
     52 	if (endp == path) {
     53 		dname[0] = *endp == '/' ? '/' : '.';
     54 		dname[1] = '\0';
     55 		return (dname);
     56 	} else {
     57 		/* Move forward past the separating slashes */
     58 		do {
     59 			endp--;
     60 		} while (endp > path && *endp == '/');
     61 	}
     62 
     63 	len = endp - path + 1;
     64 	if (len >= sizeof(dname)) {
     65 		errno = ENAMETOOLONG;
     66 		return (NULL);
     67 	}
     68 	memcpy(dname, path, len);
     69 	dname[len] = '\0';
     70 	return (dname);
     71 }
     72 #endif
     73