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 <fcntl.h> 50 #include <limits.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <unistd.h> 55 56 int fflag; /* Unlink existing files. */ 57 int Fflag; /* Remove empty directories also. */ 58 int hflag; /* Check new name for symlink first. */ 59 int iflag; /* Interactive mode. */ 60 int Pflag; /* Create hard links to symlinks. */ 61 int sflag; /* Symbolic, not hard, link. */ 62 int vflag; /* Verbose output. */ 63 int wflag; /* Warn if symlink target does not 64 * exist, and -f is not enabled. */ 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 exit(linkit(argv[0], argv[1], 0)); 94 } 95 96 while ((ch = getopt(argc, argv, "FLPfhinsvw")) != -1) 97 switch (ch) { 98 case 'F': 99 Fflag = 1; 100 break; 101 case 'L': 102 Pflag = 0; 103 break; 104 case 'P': 105 Pflag = 1; 106 break; 107 case 'f': 108 fflag = 1; 109 iflag = 0; 110 wflag = 0; 111 break; 112 case 'h': 113 case 'n': 114 hflag = 1; 115 break; 116 case 'i': 117 iflag = 1; 118 fflag = 0; 119 break; 120 case 's': 121 sflag = 1; 122 break; 123 case 'v': 124 vflag = 1; 125 break; 126 case 'w': 127 wflag = 1; 128 break; 129 case '?': 130 default: 131 usage(); 132 } 133 134 argv += optind; 135 argc -= optind; 136 137 linkch = sflag ? '-' : '='; 138 if (sflag == 0) 139 Fflag = 0; 140 if (Fflag == 1 && iflag == 0) { 141 fflag = 1; 142 wflag = 0; /* Implied when fflag != 0 */ 143 } 144 145 switch(argc) { 146 case 0: 147 usage(); 148 /* NOTREACHED */ 149 case 1: /* ln source */ 150 exit(linkit(argv[0], ".", 1)); 151 case 2: /* ln source target */ 152 exit(linkit(argv[0], argv[1], 0)); 153 default: 154 ; 155 } 156 /* ln source1 source2 directory */ 157 targetdir = argv[argc - 1]; 158 if (hflag && lstat(targetdir, &sb) == 0 && S_ISLNK(sb.st_mode)) { 159 /* 160 * We were asked not to follow symlinks, but found one at 161 * the target--simulate "not a directory" error 162 */ 163 errno = ENOTDIR; 164 err(1, "%s", targetdir); 165 } 166 if (stat(targetdir, &sb)) 167 err(1, "%s", targetdir); 168 if (!S_ISDIR(sb.st_mode)) 169 usage(); 170 for (exitval = 0; *argv != targetdir; ++argv) 171 exitval |= linkit(*argv, targetdir, 1); 172 exit(exitval); 173 } 174 175 int 176 linkit(const char *source, const char *target, int isdir) 177 { 178 struct stat sb; 179 const char *p; 180 int ch, exists, first; 181 char path[PATH_MAX]; 182 char wbuf[PATH_MAX]; 183 184 if (!sflag) { 185 /* If source doesn't exist, quit now. */ 186 if ((Pflag ? lstat : stat)(source, &sb)) { 187 warn("%s", source); 188 return (1); 189 } 190 /* Only symbolic links to directories. */ 191 if (S_ISDIR(sb.st_mode)) { 192 errno = EISDIR; 193 warn("%s", source); 194 return (1); 195 } 196 } 197 198 /* 199 * If the target is a directory (and not a symlink if hflag), 200 * append the source's name. 201 */ 202 if (isdir || 203 (lstat(target, &sb) == 0 && S_ISDIR(sb.st_mode)) || 204 (!hflag && stat(target, &sb) == 0 && S_ISDIR(sb.st_mode))) { 205 if ((p = strrchr(source, '/')) == NULL) 206 p = source; 207 else 208 ++p; 209 if (snprintf(path, sizeof(path), "%s/%s", target, p) >= 210 (ssize_t)sizeof(path)) { 211 errno = ENAMETOOLONG; 212 warn("%s", source); 213 return (1); 214 } 215 target = path; 216 } 217 218 exists = !lstat(target, &sb); 219 /* 220 * If the link source doesn't exist, and a symbolic link was 221 * requested, and -w was specified, give a warning. 222 */ 223 if (sflag && wflag) { 224 if (*source == '/') { 225 /* Absolute link source. */ 226 if (stat(source, &sb) != 0) 227 warn("warning: %s inaccessible", source); 228 } else { 229 /* 230 * Relative symlink source. Try to construct the 231 * absolute path of the source, by appending `source' 232 * to the parent directory of the target. 233 */ 234 p = strrchr(target, '/'); 235 if (p != NULL) 236 p++; 237 else 238 p = target; 239 (void)snprintf(wbuf, sizeof(wbuf), "%.*s%s", 240 (int)(p - target), target, source); 241 if (stat(wbuf, &sb) != 0) 242 warn("warning: %s", source); 243 } 244 } 245 /* 246 * If the file exists, then unlink it forcibly if -f was specified 247 * and interactively if -i was specified. 248 */ 249 if (fflag && exists) { 250 if (Fflag && S_ISDIR(sb.st_mode)) { 251 if (rmdir(target)) { 252 warn("%s", target); 253 return (1); 254 } 255 } else if (unlink(target)) { 256 warn("%s", target); 257 return (1); 258 } 259 } else if (iflag && exists) { 260 fflush(stdout); 261 fprintf(stderr, "replace %s? ", target); 262 263 first = ch = getchar(); 264 while(ch != '\n' && ch != EOF) 265 ch = getchar(); 266 if (first != 'y' && first != 'Y') { 267 fprintf(stderr, "not replaced\n"); 268 return (1); 269 } 270 271 if (Fflag && S_ISDIR(sb.st_mode)) { 272 if (rmdir(target)) { 273 warn("%s", target); 274 return (1); 275 } 276 } else if (unlink(target)) { 277 warn("%s", target); 278 return (1); 279 } 280 } 281 282 /* Attempt the link. */ 283 if (sflag ? symlink(source, target) : 284 linkat(AT_FDCWD, source, AT_FDCWD, target, 285 Pflag ? 0 : AT_SYMLINK_FOLLOW)) { 286 warn("%s", target); 287 return (1); 288 } 289 if (vflag) 290 (void)printf("%s %c> %s\n", target, linkch, source); 291 return (0); 292 } 293 294 void 295 usage(void) 296 { 297 (void)fprintf(stderr, "%s\n%s\n%s\n", 298 "usage: ln [-s [-F] | -L | -P] [-f | -i] [-hnv] source_file [target_file]", 299 " ln [-s [-F] | -L | -P] [-f | -i] [-hnv] source_file ... target_dir", 300 " link source_file target_file"); 301 exit(1); 302 } 303