1 /* $OpenBSD: dirname.c,v 1.2 1998/06/21 22:13:40 millert Exp $ */ 2 3 /* 4 * Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com> 5 * 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. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 19 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 20 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 21 * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 22 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 23 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 24 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 25 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 26 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 27 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #ifndef lint 31 static char rcsid[] = "$OpenBSD: dirname.c,v 1.2 1998/06/21 22:13:40 millert Exp $"; 32 #endif /* not lint */ 33 34 #include <errno.h> 35 #include <libgen.h> 36 #include <string.h> 37 #include <sys/param.h> 38 39 char * 40 dirname(path) 41 char *path; 42 { 43 static char bname[MAXPATHLEN]; 44 register char *endp; 45 46 /* Empty or NULL string gets treated as "." */ 47 if (path == NULL || *path == '\0') { 48 (void)strcpy(bname, "."); 49 return(bname); 50 } 51 52 /* Strip trailing slashes */ 53 endp = path + strlen(path) - 1; 54 while (endp > path && *endp == '/') 55 endp--; 56 57 /* Find the start of the dir */ 58 while (endp > path && *endp != '/') 59 endp--; 60 61 /* Either the dir is "/" or there are no slashes */ 62 if (endp == path) { 63 (void)strcpy(bname, *endp == '/' ? "/" : "."); 64 return(bname); 65 } else { 66 do { 67 endp--; 68 } while (endp > path && *endp == '/'); 69 } 70 71 if (endp - path + 1 > sizeof(bname)) { 72 errno = ENAMETOOLONG; 73 return(NULL); 74 } 75 (void)strncpy(bname, path, endp - path + 1); 76 bname[endp - path + 1] = '\0'; 77 return(bname); 78 } 79