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@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 #include <errno.h> 20 #include <libgen.h> 21 #include <string.h> 22 #include <sys/param.h> 23 24 char * 25 dirname(const char *path) 26 { 27 static char dname[MAXPATHLEN]; 28 size_t len; 29 const char *endp; 30 31 /* Empty or NULL string gets treated as "." */ 32 if (path == NULL || *path == '\0') { 33 dname[0] = '.'; 34 dname[1] = '\0'; 35 return (dname); 36 } 37 38 /* Strip any trailing slashes */ 39 endp = path + strlen(path) - 1; 40 while (endp > path && *endp == '/') 41 endp--; 42 43 /* Find the start of the dir */ 44 while (endp > path && *endp != '/') 45 endp--; 46 47 /* Either the dir is "/" or there are no slashes */ 48 if (endp == path) { 49 dname[0] = *endp == '/' ? '/' : '.'; 50 dname[1] = '\0'; 51 return (dname); 52 } else { 53 /* Move forward past the separating slashes */ 54 do { 55 endp--; 56 } while (endp > path && *endp == '/'); 57 } 58 59 len = endp - path + 1; 60 if (len >= sizeof(dname)) { 61 errno = ENAMETOOLONG; 62 return (NULL); 63 } 64 memcpy(dname, path, len); 65 dname[len] = '\0'; 66 return (dname); 67 } 68