1 /* $NetBSD: rm.c,v 1.20 1997/07/20 20:51:09 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 __COPYRIGHT("@(#) Copyright (c) 1990, 1993, 1994\n\ 39 The Regents of the University of California. All rights reserved.\n"); 40 #endif /* not lint */ 41 42 #ifndef lint 43 #if 0 44 static char sccsid[] = "@(#)rm.c 8.8 (Berkeley) 4/27/95"; 45 #else 46 __RCSID("$NetBSD: rm.c,v 1.20 1997/07/20 20:51:09 christos Exp $"); 47 #endif 48 #endif /* not lint */ 49 50 #include <sys/types.h> 51 #include <sys/stat.h> 52 53 #include <locale.h> 54 #include <err.h> 55 #include <errno.h> 56 #include <fcntl.h> 57 #include <fts.h> 58 #include <stdio.h> 59 #include <stdlib.h> 60 #include <string.h> 61 #include <unistd.h> 62 #include <pwd.h> 63 #include <grp.h> 64 65 int dflag, eval, fflag, iflag, Pflag, Wflag, stdin_ok; 66 67 int check __P((char *, char *, struct stat *)); 68 void checkdot __P((char **)); 69 void rm_file __P((char **)); 70 void rm_overwrite __P((char *, struct stat *)); 71 void rm_tree __P((char **)); 72 void usage __P((void)); 73 int main __P((int, char *[])); 74 75 /* 76 * rm -- 77 * This rm is different from historic rm's, but is expected to match 78 * POSIX 1003.2 behavior. The most visible difference is that -f 79 * has two specific effects now, ignore non-existent files and force 80 * file removal. 81 */ 82 int 83 main(argc, argv) 84 int argc; 85 char *argv[]; 86 { 87 int ch, rflag; 88 89 setlocale(LC_ALL, ""); 90 91 Pflag = rflag = 0; 92 while ((ch = getopt(argc, argv, "dfiPRrW")) != -1) 93 switch(ch) { 94 case 'd': 95 dflag = 1; 96 break; 97 case 'f': 98 fflag = 1; 99 iflag = 0; 100 break; 101 case 'i': 102 fflag = 0; 103 iflag = 1; 104 break; 105 case 'P': 106 Pflag = 1; 107 break; 108 case 'R': 109 case 'r': /* Compatibility. */ 110 rflag = 1; 111 break; 112 case 'W': 113 Wflag = 1; 114 break; 115 case '?': 116 default: 117 usage(); 118 } 119 argc -= optind; 120 argv += optind; 121 122 if (argc < 1) 123 usage(); 124 125 checkdot(argv); 126 127 if (*argv) { 128 stdin_ok = isatty(STDIN_FILENO); 129 130 if (rflag) 131 rm_tree(argv); 132 else 133 rm_file(argv); 134 } 135 136 exit (eval); 137 } 138 139 void 140 rm_tree(argv) 141 char **argv; 142 { 143 FTS *fts; 144 FTSENT *p; 145 int needstat; 146 int flags; 147 148 /* 149 * Remove a file hierarchy. If forcing removal (-f), or interactive 150 * (-i) or can't ask anyway (stdin_ok), don't stat the file. 151 */ 152 needstat = !fflag && !iflag && stdin_ok; 153 154 /* 155 * If the -i option is specified, the user can skip on the pre-order 156 * visit. The fts_number field flags skipped directories. 157 */ 158 #define SKIPPED 1 159 160 flags = FTS_PHYSICAL; 161 if (!needstat) 162 flags |= FTS_NOSTAT; 163 if (Wflag) 164 flags |= FTS_WHITEOUT; 165 if (!(fts = fts_open(argv, flags, 166 (int (*) __P((const FTSENT **, const FTSENT **)))NULL))) 167 err(1, "%s", ""); 168 while ((p = fts_read(fts)) != NULL) { 169 switch (p->fts_info) { 170 case FTS_DNR: 171 if (!fflag || p->fts_errno != ENOENT) { 172 warnx("%s: %s", 173 p->fts_path, strerror(p->fts_errno)); 174 eval = 1; 175 } 176 continue; 177 case FTS_ERR: 178 errx(1, "%s: %s", p->fts_path, strerror(p->fts_errno)); 179 case FTS_NS: 180 /* 181 * FTS_NS: assume that if can't stat the file, it 182 * can't be unlinked. 183 */ 184 if (!needstat) 185 break; 186 if (!fflag || p->fts_errno != ENOENT) { 187 warnx("%s: %s", 188 p->fts_path, strerror(p->fts_errno)); 189 eval = 1; 190 } 191 continue; 192 case FTS_D: 193 /* Pre-order: give user chance to skip. */ 194 if (!fflag && !check(p->fts_path, p->fts_accpath, 195 p->fts_statp)) { 196 (void)fts_set(fts, p, FTS_SKIP); 197 p->fts_number = SKIPPED; 198 } 199 continue; 200 case FTS_DP: 201 /* Post-order: see if user skipped. */ 202 if (p->fts_number == SKIPPED) 203 continue; 204 break; 205 default: 206 if (!fflag && 207 !check(p->fts_path, p->fts_accpath, p->fts_statp)) 208 continue; 209 } 210 211 /* 212 * If we can't read or search the directory, may still be 213 * able to remove it. Don't print out the un{read,search}able 214 * message unless the remove fails. 215 */ 216 switch (p->fts_info) { 217 case FTS_DP: 218 case FTS_DNR: 219 if (!rmdir(p->fts_accpath) || 220 (fflag && errno == ENOENT)) 221 continue; 222 break; 223 224 case FTS_W: 225 if (!undelete(p->fts_accpath) || 226 (fflag && errno == ENOENT)) 227 continue; 228 break; 229 230 default: 231 if (Pflag) 232 rm_overwrite(p->fts_accpath, NULL); 233 if (!unlink(p->fts_accpath) || 234 (fflag && errno == ENOENT)) 235 continue; 236 } 237 warn("%s", p->fts_path); 238 eval = 1; 239 } 240 if (errno) 241 err(1, "fts_read"); 242 } 243 244 void 245 rm_file(argv) 246 char **argv; 247 { 248 struct stat sb; 249 int rval; 250 char *f; 251 252 /* 253 * Remove a file. POSIX 1003.2 states that, by default, attempting 254 * to remove a directory is an error, so must always stat the file. 255 */ 256 while ((f = *argv++) != NULL) { 257 /* Assume if can't stat the file, can't unlink it. */ 258 if (lstat(f, &sb)) { 259 if (Wflag) { 260 sb.st_mode = S_IFWHT|S_IWUSR|S_IRUSR; 261 } else { 262 if (!fflag || errno != ENOENT) { 263 warn("%s", f); 264 eval = 1; 265 } 266 continue; 267 } 268 } else if (Wflag) { 269 warnx("%s: %s", f, strerror(EEXIST)); 270 eval = 1; 271 continue; 272 } 273 274 if (S_ISDIR(sb.st_mode) && !dflag) { 275 warnx("%s: is a directory", f); 276 eval = 1; 277 continue; 278 } 279 if (!fflag && !S_ISWHT(sb.st_mode) && !check(f, f, &sb)) 280 continue; 281 if (S_ISWHT(sb.st_mode)) 282 rval = undelete(f); 283 else if (S_ISDIR(sb.st_mode)) 284 rval = rmdir(f); 285 else { 286 if (Pflag) 287 rm_overwrite(f, &sb); 288 rval = unlink(f); 289 } 290 if (rval && (!fflag || errno != ENOENT)) { 291 warn("%s", f); 292 eval = 1; 293 } 294 } 295 } 296 297 /* 298 * rm_overwrite -- 299 * Overwrite the file 3 times with varying bit patterns. 300 * 301 * XXX 302 * This is a cheap way to *really* delete files. Note that only regular 303 * files are deleted, directories (and therefore names) will remain. 304 * Also, this assumes a fixed-block file system (like FFS, or a V7 or a 305 * System V file system). In a logging file system, you'll have to have 306 * kernel support. 307 */ 308 void 309 rm_overwrite(file, sbp) 310 char *file; 311 struct stat *sbp; 312 { 313 struct stat sb; 314 off_t len; 315 int fd, wlen; 316 char buf[8 * 1024]; 317 318 fd = -1; 319 if (sbp == NULL) { 320 if (lstat(file, &sb)) 321 goto err; 322 sbp = &sb; 323 } 324 if (!S_ISREG(sbp->st_mode)) 325 return; 326 if ((fd = open(file, O_WRONLY, 0)) == -1) 327 goto err; 328 329 #define PASS(byte) { \ 330 memset(buf, byte, sizeof(buf)); \ 331 for (len = sbp->st_size; len > 0; len -= wlen) { \ 332 wlen = len < sizeof(buf) ? len : sizeof(buf); \ 333 if (write(fd, buf, wlen) != wlen) \ 334 goto err; \ 335 } \ 336 } 337 PASS(0xff); 338 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 339 goto err; 340 PASS(0x00); 341 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 342 goto err; 343 PASS(0xff); 344 if (!fsync(fd) && !close(fd)) 345 return; 346 347 err: eval = 1; 348 warn("%s", file); 349 } 350 351 352 int 353 check(path, name, sp) 354 char *path, *name; 355 struct stat *sp; 356 { 357 int ch, first; 358 char modep[15]; 359 360 /* Check -i first. */ 361 if (iflag) 362 (void)fprintf(stderr, "remove %s? ", path); 363 else { 364 /* 365 * If it's not a symbolic link and it's unwritable and we're 366 * talking to a terminal, ask. Symbolic links are excluded 367 * because their permissions are meaningless. Check stdin_ok 368 * first because we may not have stat'ed the file. 369 */ 370 if (!stdin_ok || S_ISLNK(sp->st_mode) || !access(name, W_OK)) 371 return (1); 372 strmode(sp->st_mode, modep); 373 (void)fprintf(stderr, "override %s%s%s/%s for %s? ", 374 modep + 1, modep[9] == ' ' ? "" : " ", 375 user_from_uid(sp->st_uid, 0), 376 group_from_gid(sp->st_gid, 0), path); 377 } 378 (void)fflush(stderr); 379 380 first = ch = getchar(); 381 while (ch != '\n' && ch != EOF) 382 ch = getchar(); 383 return (first == 'y' || first == 'Y'); 384 } 385 386 /* 387 * POSIX.2 requires that if "." or ".." are specified as the basename 388 * portion of an operand, a diagnostic message be written to standard 389 * error and nothing more be done with such operands. 390 * 391 * Since POSIX.2 defines basename as the final portion of a path after 392 * trailing slashes have been removed, we'll remove them here. 393 */ 394 #define ISDOT(a) ((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2]))) 395 void 396 checkdot(argv) 397 char **argv; 398 { 399 char *p, **save, **t; 400 int complained; 401 402 complained = 0; 403 for (t = argv; *t;) { 404 /* strip trailing slashes */ 405 p = strrchr (*t, '\0'); 406 while (--p > *t && *p == '/') 407 *p = '\0'; 408 409 /* extract basename */ 410 if ((p = strrchr(*t, '/')) != NULL) 411 ++p; 412 else 413 p = *t; 414 415 if (ISDOT(p)) { 416 if (!complained++) 417 warnx("\".\" and \"..\" may not be removed"); 418 eval = 1; 419 for (save = t; (t[0] = t[1]) != NULL; ++t) 420 continue; 421 t = save; 422 } else 423 ++t; 424 } 425 } 426 427 void 428 usage() 429 { 430 431 (void)fprintf(stderr, "usage: rm [-dfiPRrW] file ...\n"); 432 exit(1); 433 } 434