dirname.c revision 1590
11590Srgrimes/*- 21590Srgrimes * Copyright (c) 1991, 1993, 1994 31590Srgrimes * The Regents of the University of California. All rights reserved. 41590Srgrimes * 51590Srgrimes * Redistribution and use in source and binary forms, with or without 61590Srgrimes * modification, are permitted provided that the following conditions 71590Srgrimes * are met: 81590Srgrimes * 1. Redistributions of source code must retain the above copyright 91590Srgrimes * notice, this list of conditions and the following disclaimer. 101590Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 111590Srgrimes * notice, this list of conditions and the following disclaimer in the 121590Srgrimes * documentation and/or other materials provided with the distribution. 131590Srgrimes * 3. All advertising materials mentioning features or use of this software 141590Srgrimes * must display the following acknowledgement: 151590Srgrimes * This product includes software developed by the University of 161590Srgrimes * California, Berkeley and its contributors. 171590Srgrimes * 4. Neither the name of the University nor the names of its contributors 181590Srgrimes * may be used to endorse or promote products derived from this software 191590Srgrimes * without specific prior written permission. 201590Srgrimes * 211590Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 221590Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 231590Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 241590Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 251590Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 261590Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 271590Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 281590Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 291590Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 301590Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 311590Srgrimes * SUCH DAMAGE. 321590Srgrimes */ 331590Srgrimes 341590Srgrimes#ifndef lint 351590Srgrimesstatic char copyright[] = 361590Srgrimes"@(#) Copyright (c) 1991, 1993, 1994\n\ 371590Srgrimes The Regents of the University of California. All rights reserved.\n"; 381590Srgrimes#endif /* not lint */ 391590Srgrimes 401590Srgrimes#ifndef lint 411590Srgrimesstatic char sccsid[] = "@(#)dirname.c 8.3 (Berkeley) 4/2/94"; 421590Srgrimes#endif /* not lint */ 431590Srgrimes 441590Srgrimes#include <stdio.h> 451590Srgrimes#include <stdlib.h> 461590Srgrimes 471590Srgrimesvoid usage __P((void)); 481590Srgrimes 491590Srgrimesint 501590Srgrimesmain(argc, argv) 511590Srgrimes int argc; 521590Srgrimes char **argv; 531590Srgrimes{ 541590Srgrimes char *p; 551590Srgrimes int ch; 561590Srgrimes 571590Srgrimes while ((ch = getopt(argc, argv, "")) != EOF) 581590Srgrimes switch(ch) { 591590Srgrimes case '?': 601590Srgrimes default: 611590Srgrimes usage(); 621590Srgrimes } 631590Srgrimes argc -= optind; 641590Srgrimes argv += optind; 651590Srgrimes 661590Srgrimes if (argc != 1) 671590Srgrimes usage(); 681590Srgrimes 691590Srgrimes /* 701590Srgrimes * (1) If string is //, skip steps (2) through (5). 711590Srgrimes * (2) If string consists entirely of slash characters, string 721590Srgrimes * shall be set to a single slash character. In this case, 731590Srgrimes * skip steps (3) through (8). 741590Srgrimes */ 751590Srgrimes for (p = *argv;; ++p) { 761590Srgrimes if (!*p) { 771590Srgrimes if (p > *argv) 781590Srgrimes (void)printf("/\n"); 791590Srgrimes else 801590Srgrimes (void)printf(".\n"); 811590Srgrimes exit(0); 821590Srgrimes } 831590Srgrimes if (*p != '/') 841590Srgrimes break; 851590Srgrimes } 861590Srgrimes 871590Srgrimes /* 881590Srgrimes * (3) If there are any trailing slash characters in string, they 891590Srgrimes * shall be removed. 901590Srgrimes */ 911590Srgrimes for (; *p; ++p); 921590Srgrimes while (*--p == '/') 931590Srgrimes continue; 941590Srgrimes *++p = '\0'; 951590Srgrimes 961590Srgrimes /* 971590Srgrimes * (4) If there are no slash characters remaining in string, 981590Srgrimes * string shall be set to a single period character. In this 991590Srgrimes * case skip steps (5) through (8). 1001590Srgrimes * 1011590Srgrimes * (5) If there are any trailing nonslash characters in string, 1021590Srgrimes * they shall be removed. 1031590Srgrimes */ 1041590Srgrimes while (--p >= *argv) 1051590Srgrimes if (*p == '/') 1061590Srgrimes break; 1071590Srgrimes ++p; 1081590Srgrimes if (p == *argv) { 1091590Srgrimes (void)printf(".\n"); 1101590Srgrimes exit(0); 1111590Srgrimes } 1121590Srgrimes 1131590Srgrimes /* 1141590Srgrimes * (6) If the remaining string is //, it is implementation defined 1151590Srgrimes * whether steps (7) and (8) are skipped or processed. 1161590Srgrimes * 1171590Srgrimes * This case has already been handled, as part of steps (1) and (2). 1181590Srgrimes */ 1191590Srgrimes 1201590Srgrimes /* 1211590Srgrimes * (7) If there are any trailing slash characters in string, they 1221590Srgrimes * shall be removed. 1231590Srgrimes */ 1241590Srgrimes while (--p >= *argv) 1251590Srgrimes if (*p != '/') 1261590Srgrimes break; 1271590Srgrimes ++p; 1281590Srgrimes 1291590Srgrimes /* 1301590Srgrimes * (8) If the remaining string is empty, string shall be set to 1311590Srgrimes * a single slash character. 1321590Srgrimes */ 1331590Srgrimes *p = '\0'; 1341590Srgrimes (void)printf("%s\n", p == *argv ? "/" : *argv); 1351590Srgrimes exit(0); 1361590Srgrimes} 1371590Srgrimes 1381590Srgrimesvoid 1391590Srgrimesusage() 1401590Srgrimes{ 1411590Srgrimes 1421590Srgrimes (void)fprintf(stderr, "usage: dirname path\n"); 1431590Srgrimes exit(1); 1441590Srgrimes} 145