1 /* 2 * Copyright (c) 1987, 1993, 1994 3 * The Regents of the University of California. 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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 static char const copyright[] = 36 "@(#) Copyright (c) 1987, 1993, 1994\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 #if 0 42 static char sccsid[] = "@(#)ln.c 8.2 (Berkeley) 3/31/94"; 43 #endif 44 static const char rcsid[] = 45 "$FreeBSD$"; 46 #endif /* not lint */ 47 48 #include <sys/param.h> 49 #include <sys/stat.h> 50 51 #include <err.h> 52 #include <errno.h> 53 #include <limits.h> 54 #include <stdio.h> 55 #include <stdlib.h> 56 #include <string.h> 57 #include <unistd.h> 58 59 int fflag; /* Unlink existing files. */ 60 int hflag; /* Check new name for symlink first. */ 61 int iflag; /* Interactive mode. */ 62 int sflag; /* Symbolic, not hard, link. */ 63 int vflag; /* Verbose output. */ 64 /* System link call. */ 65 int (*linkf)(const char *, const char *); 66 char linkch; 67 68 int linkit(const char *, const char *, int); 69 void usage(void); 70 71 int 72 main(int argc, char *argv[]) 73 { 74 struct stat sb; 75 char *p, *sourcedir; 76 int ch, exitval; 77 78 /* 79 * Test for the special case where the utility is called as 80 * "link", for which the functionality provided is greatly 81 * simplified. 82 */ 83 if ((p = rindex(argv[0], '/')) == NULL) 84 p = argv[0]; 85 else 86 ++p; 87 if (strcmp(p, "link") == 0) { 88 if (argc == 3) { 89 linkf = link; 90 exit(linkit(argv[1], argv[2], 0)); 91 } else 92 usage(); 93 } 94 95 while ((ch = getopt(argc, argv, "fhinsv")) != -1) 96 switch (ch) { 97 case 'f': 98 fflag = 1; 99 iflag = 0; 100 break; 101 case 'h': 102 case 'n': 103 hflag = 1; 104 break; 105 case 'i': 106 iflag = 1; 107 fflag = 0; 108 break; 109 case 's': 110 sflag = 1; 111 break; 112 case 'v': 113 vflag = 1; 114 break; 115 case '?': 116 default: 117 usage(); 118 } 119 120 argv += optind; 121 argc -= optind; 122 123 linkf = sflag ? symlink : link; 124 linkch = sflag ? '-' : '='; 125 126 switch(argc) { 127 case 0: 128 usage(); 129 /* NOTREACHED */ 130 case 1: /* ln target */ 131 exit(linkit(argv[0], ".", 1)); 132 case 2: /* ln target source */ 133 exit(linkit(argv[0], argv[1], 0)); 134 default: 135 } 136 /* ln target1 target2 directory */ 137 sourcedir = argv[argc - 1]; 138 if (hflag && lstat(sourcedir, &sb) == 0 && S_ISLNK(sb.st_mode)) { 139 /* 140 * We were asked not to follow symlinks, but found one at 141 * the target--simulate "not a directory" error 142 */ 143 errno = ENOTDIR; 144 err(1, "%s", sourcedir); 145 } 146 if (stat(sourcedir, &sb)) 147 err(1, "%s", sourcedir); 148 if (!S_ISDIR(sb.st_mode)) 149 usage(); 150 for (exitval = 0; *argv != sourcedir; ++argv) 151 exitval |= linkit(*argv, sourcedir, 1); 152 exit(exitval); 153 } 154 155 int 156 linkit(const char *target, const char *source, int isdir) 157 { 158 struct stat sb; 159 const char *p; 160 int ch, exists, first; 161 char path[PATH_MAX]; 162 163 if (!sflag) { 164 /* If target doesn't exist, quit now. */ 165 if (stat(target, &sb)) { 166 warn("%s", target); 167 return (1); 168 } 169 /* Only symbolic links to directories. */ 170 if (S_ISDIR(sb.st_mode)) { 171 errno = EISDIR; 172 warn("%s", target); 173 return (1); 174 } 175 } 176 177 /* 178 * If the source is a directory (and not a symlink if hflag), 179 * append the target's name. 180 */ 181 if (isdir || 182 (lstat(source, &sb) == 0 && S_ISDIR(sb.st_mode)) || 183 (!hflag && stat(source, &sb) == 0 && S_ISDIR(sb.st_mode))) { 184 if ((p = strrchr(target, '/')) == NULL) 185 p = target; 186 else 187 ++p; 188 (void)snprintf(path, sizeof(path), "%s/%s", source, p); 189 source = path; 190 } 191 192 exists = !lstat(source, &sb); 193 /* 194 * If the file exists, then unlink it forcibly if -f was specified 195 * and interactively if -i was specified. 196 */ 197 if (fflag && exists) { 198 if (unlink(source)) { 199 warn("%s", source); 200 return (1); 201 } 202 } else if (iflag && exists) { 203 fflush(stdout); 204 fprintf(stderr, "replace %s? ", source); 205 206 first = ch = getchar(); 207 while(ch != '\n' && ch != EOF) 208 ch = getchar(); 209 if (first != 'y' && first != 'Y') { 210 fprintf(stderr, "not replaced\n"); 211 return (1); 212 } 213 214 if (unlink(source)) { 215 warn("%s", source); 216 return (1); 217 } 218 } 219 220 /* Attempt the link. */ 221 if ((*linkf)(target, source)) { 222 warn("%s", source); 223 return (1); 224 } 225 if (vflag) 226 (void)printf("%s %c> %s\n", source, linkch, target); 227 return (0); 228 } 229 230 void 231 usage(void) 232 { 233 (void)fprintf(stderr, "%s\n%s\n%s\n", 234 "usage: ln [-fhinsv] file1 file2", 235 " ln [-fhinsv] file ... directory", 236 " link file1 file2"); 237 exit(1); 238 } 239