1 /*- 2 * Copyright (c) 1991, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #ifndef lint 9 static char copyright[] = 10 "@(#) Copyright (c) 1991, 1993, 1994\n\ 11 The Regents of the University of California. All rights reserved.\n"; 12 #endif /* not lint */ 13 14 #ifndef lint 15 static char sccsid[] = "@(#)dirname.c 8.4 (Berkeley) 05/04/95"; 16 #endif /* not lint */ 17 18 #include <stdio.h> 19 #include <stdlib.h> 20 #include <unistd.h> 21 22 void usage __P((void)); 23 24 int 25 main(argc, argv) 26 int argc; 27 char **argv; 28 { 29 char *p; 30 int ch; 31 32 while ((ch = getopt(argc, argv, "")) != EOF) 33 switch(ch) { 34 case '?': 35 default: 36 usage(); 37 } 38 argc -= optind; 39 argv += optind; 40 41 if (argc != 1) 42 usage(); 43 44 /* 45 * (1) If string is //, skip steps (2) through (5). 46 * (2) If string consists entirely of slash characters, string 47 * shall be set to a single slash character. In this case, 48 * skip steps (3) through (8). 49 */ 50 for (p = *argv;; ++p) { 51 if (!*p) { 52 if (p > *argv) 53 (void)printf("/\n"); 54 else 55 (void)printf(".\n"); 56 exit(0); 57 } 58 if (*p != '/') 59 break; 60 } 61 62 /* 63 * (3) If there are any trailing slash characters in string, they 64 * shall be removed. 65 */ 66 for (; *p; ++p); 67 while (*--p == '/') 68 continue; 69 *++p = '\0'; 70 71 /* 72 * (4) If there are no slash characters remaining in string, 73 * string shall be set to a single period character. In this 74 * case skip steps (5) through (8). 75 * 76 * (5) If there are any trailing nonslash characters in string, 77 * they shall be removed. 78 */ 79 while (--p >= *argv) 80 if (*p == '/') 81 break; 82 ++p; 83 if (p == *argv) { 84 (void)printf(".\n"); 85 exit(0); 86 } 87 88 /* 89 * (6) If the remaining string is //, it is implementation defined 90 * whether steps (7) and (8) are skipped or processed. 91 * 92 * This case has already been handled, as part of steps (1) and (2). 93 */ 94 95 /* 96 * (7) If there are any trailing slash characters in string, they 97 * shall be removed. 98 */ 99 while (--p >= *argv) 100 if (*p != '/') 101 break; 102 ++p; 103 104 /* 105 * (8) If the remaining string is empty, string shall be set to 106 * a single slash character. 107 */ 108 *p = '\0'; 109 (void)printf("%s\n", p == *argv ? "/" : *argv); 110 exit(0); 111 } 112 113 void 114 usage() 115 { 116 117 (void)fprintf(stderr, "usage: dirname path\n"); 118 exit(1); 119 } 120