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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #if 0 31 #ifndef lint 32 static char const copyright[] = 33 "@(#) Copyright (c) 1987, 1993, 1994\n\ 34 The Regents of the University of California. All rights reserved.\n"; 35 #endif /* not lint */ 36 37 #ifndef lint 38 static char sccsid[] = "@(#)ln.c 8.2 (Berkeley) 3/31/94"; 39 #endif /* not lint */ 40 #endif 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include <sys/param.h> 45 #include <sys/stat.h> 46 47 #include <err.h> 48 #include <errno.h> 49 #include <limits.h> 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <string.h> 53 #include <unistd.h> 54 55 int fflag; /* Unlink existing files. */ 56 int Fflag; /* Remove empty directories also. */ 57 int hflag; /* Check new name for symlink first. */ 58 int iflag; /* Interactive mode. */ 59 int sflag; /* Symbolic, not hard, link. */ 60 int vflag; /* Verbose output. */ 61 int wflag; /* Warn if symlink target does not 62 * exist, and -f is not enabled. */ 63 /* System link call. */ 64 int (*linkf)(const char *, const char *); 65 char linkch; 66 67 int linkit(const char *, const char *, int); 68 void usage(void); 69 70 int 71 main(int argc, char *argv[]) 72 { 73 struct stat sb; 74 char *p, *targetdir; 75 int ch, exitval; 76 77 /* 78 * Test for the special case where the utility is called as 79 * "link", for which the functionality provided is greatly 80 * simplified. 81 */ 82 if ((p = rindex(argv[0], '/')) == NULL) 83 p = argv[0]; 84 else 85 ++p; 86 if (strcmp(p, "link") == 0) { 87 while (getopt(argc, argv, "") != -1) 88 usage(); 89 argc -= optind; 90 argv += optind; 91 if (argc != 2) 92 usage(); 93 linkf = link; 94 exit(linkit(argv[0], argv[1], 0)); 95 } 96 97 while ((ch = getopt(argc, argv, "Ffhinsvw")) != -1) 98 switch (ch) { 99 case 'F': 100 Fflag = 1; 101 break; 102 case 'f': 103 fflag = 1; 104 iflag = 0; 105 wflag = 0; 106 break; 107 case 'h': 108 case 'n': 109 hflag = 1; 110 break; 111 case 'i': 112 iflag = 1; 113 fflag = 0; 114 break; 115 case 's': 116 sflag = 1; 117 break; 118 case 'v': 119 vflag = 1; 120 break; 121 case 'w': 122 wflag = 1; 123 break; 124 case '?': 125 default: 126 usage(); 127 } 128 129 argv += optind; 130 argc -= optind; 131 132 linkf = sflag ? symlink : link; 133 linkch = sflag ? '-' : '='; 134 if (sflag == 0) 135 Fflag = 0; 136 if (Fflag == 1 && iflag == 0) { 137 fflag = 1; 138 wflag = 0; /* Implied when fflag != 0 */ 139 } 140 141 switch(argc) { 142 case 0: 143 usage(); 144 /* NOTREACHED */ 145 case 1: /* ln source */ 146 exit(linkit(argv[0], ".", 1)); 147 case 2: /* ln source target */ 148 exit(linkit(argv[0], argv[1], 0)); 149 default: 150 ; 151 } 152 /* ln source1 source2 directory */ 153 targetdir = argv[argc - 1]; 154 if (hflag && lstat(targetdir, &sb) == 0 && S_ISLNK(sb.st_mode)) { 155 /* 156 * We were asked not to follow symlinks, but found one at 157 * the target--simulate "not a directory" error 158 */ 159 errno = ENOTDIR; 160 err(1, "%s", targetdir); 161 } 162 if (stat(targetdir, &sb)) 163 err(1, "%s", targetdir); 164 if (!S_ISDIR(sb.st_mode)) 165 usage(); 166 for (exitval = 0; *argv != targetdir; ++argv) 167 exitval |= linkit(*argv, targetdir, 1); 168 exit(exitval); 169 } 170 171 int 172 linkit(const char *source, const char *target, int isdir) 173 { 174 struct stat sb; 175 const char *p; 176 int ch, exists, first; 177 char path[PATH_MAX]; 178 char wbuf[PATH_MAX]; 179 180 if (!sflag) { 181 /* If source doesn't exist, quit now. */ 182 if (stat(source, &sb)) { 183 warn("%s", source); 184 return (1); 185 } 186 /* Only symbolic links to directories. */ 187 if (S_ISDIR(sb.st_mode)) { 188 errno = EISDIR; 189 warn("%s", source); 190 return (1); 191 } 192 } 193 194 /* 195 * If the target is a directory (and not a symlink if hflag), 196 * append the source's name. 197 */ 198 if (isdir || 199 (lstat(target, &sb) == 0 && S_ISDIR(sb.st_mode)) || 200 (!hflag && stat(target, &sb) == 0 && S_ISDIR(sb.st_mode))) { 201 if ((p = strrchr(source, '/')) == NULL) 202 p = source; 203 else 204 ++p; 205 if (snprintf(path, sizeof(path), "%s/%s", target, p) >= 206 (ssize_t)sizeof(path)) { 207 errno = ENAMETOOLONG; 208 warn("%s", source); 209 return (1); 210 } 211 target = path; 212 } 213 214 exists = !lstat(target, &sb); 215 /* 216 * If the link source doesn't exist, and a symbolic link was 217 * requested, and -w was specified, give a warning. 218 */ 219 if (sflag && wflag) { 220 if (*source == '/') { 221 /* Absolute link source. */ 222 if (stat(source, &sb) != 0) 223 warn("warning: %s inaccessible", source); 224 } else { 225 /* 226 * Relative symlink source. Try to construct the 227 * absolute path of the source, by appending `source' 228 * to the parent directory of the target. 229 */ 230 p = strrchr(target, '/'); 231 if (p != NULL) 232 p++; 233 else 234 p = target; 235 (void)snprintf(wbuf, sizeof(wbuf), "%.*s%s", 236 (int)(p - target), target, source); 237 if (stat(wbuf, &sb) != 0) 238 warn("warning: %s", source); 239 } 240 } 241 /* 242 * If the file exists, then unlink it forcibly if -f was specified 243 * and interactively if -i was specified. 244 */ 245 if (fflag && exists) { 246 if (Fflag && S_ISDIR(sb.st_mode)) { 247 if (rmdir(target)) { 248 warn("%s", target); 249 return (1); 250 } 251 } else if (unlink(target)) { 252 warn("%s", target); 253 return (1); 254 } 255 } else if (iflag && exists) { 256 fflush(stdout); 257 fprintf(stderr, "replace %s? ", target); 258 259 first = ch = getchar(); 260 while(ch != '\n' && ch != EOF) 261 ch = getchar(); 262 if (first != 'y' && first != 'Y') { 263 fprintf(stderr, "not replaced\n"); 264 return (1); 265 } 266 267 if (Fflag && S_ISDIR(sb.st_mode)) { 268 if (rmdir(target)) { 269 warn("%s", target); 270 return (1); 271 } 272 } else if (unlink(target)) { 273 warn("%s", target); 274 return (1); 275 } 276 } 277 278 /* Attempt the link. */ 279 if ((*linkf)(source, target)) { 280 warn("%s", target); 281 return (1); 282 } 283 if (vflag) 284 (void)printf("%s %c> %s\n", target, linkch, source); 285 return (0); 286 } 287 288 void 289 usage(void) 290 { 291 (void)fprintf(stderr, "%s\n%s\n%s\n", 292 "usage: ln [-s [-F]] [-f | -i] [-hnv] source_file [target_file]", 293 " ln [-s [-F]] [-f | -i] [-hnv] source_file ... target_dir", 294 " link source_file target_file"); 295 exit(1); 296 } 297