dirname.c revision 89999
1/* 2 * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 17 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 18 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 19 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28#ifndef lint 29#if 0 30static char rcsid[] = "$OpenBSD: dirname.c,v 1.4 1999/05/30 17:10:30 espie Exp $"; 31#endif 32#endif /* not lint */ 33__FBSDID("$FreeBSD: head/lib/libc/gen/dirname.c 89999 2002-01-30 21:36:57Z obrien $"); 34 35#include <errno.h> 36#include <libgen.h> 37#include <string.h> 38#include <sys/param.h> 39 40char * 41dirname(path) 42 const char *path; 43{ 44 static char bname[MAXPATHLEN]; 45 register const char *endp; 46 47 /* Empty or NULL string gets treated as "." */ 48 if (path == NULL || *path == '\0') { 49 (void)strcpy(bname, "."); 50 return(bname); 51 } 52 53 /* Strip trailing slashes */ 54 endp = path + strlen(path) - 1; 55 while (endp > path && *endp == '/') 56 endp--; 57 58 /* Find the start of the dir */ 59 while (endp > path && *endp != '/') 60 endp--; 61 62 /* Either the dir is "/" or there are no slashes */ 63 if (endp == path) { 64 (void)strcpy(bname, *endp == '/' ? "/" : "."); 65 return(bname); 66 } else { 67 do { 68 endp--; 69 } while (endp > path && *endp == '/'); 70 } 71 72 if (endp - path + 2 > sizeof(bname)) { 73 errno = ENAMETOOLONG; 74 return(NULL); 75 } 76 (void)strncpy(bname, path, endp - path + 1); 77 bname[endp - path + 1] = '\0'; 78 return(bname); 79} 80