rm.c revision 51230
189495Snyan/*- 289495Snyan * Copyright (c) 1990, 1993, 1994 3125625Snyan * The Regents of the University of California. All rights reserved. 4125778Snyan * 5125625Snyan * Redistribution and use in source and binary forms, with or without 6125625Snyan * modification, are permitted provided that the following conditions 7139103Sru * are met: 8125563Snyan * 1. Redistributions of source code must retain the above copyright 9117053Sru * notice, this list of conditions and the following disclaimer. 10125567Sru * 2. Redistributions in binary form must reproduce the above copyright 1189495Snyan * notice, this list of conditions and the following disclaimer in the 12125625Snyan * documentation and/or other materials provided with the distribution. 13125625Snyan * 3. All advertising materials mentioning features or use of this software 1489495Snyan * must display the following acknowledgement: 1589495Snyan * This product includes software developed by the University of 1689495Snyan * California, Berkeley and its contributors. 1789495Snyan * 4. Neither the name of the University nor the names of its contributors 18125625Snyan * may be used to endorse or promote products derived from this software 19125625Snyan * without specific prior written permission. 20104234Speter * 2189495Snyan * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22117053Sru * 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 35static const char copyright[] = 36"@(#) Copyright (c) 1990, 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 42static char sccsid[] = "@(#)rm.c 8.5 (Berkeley) 4/18/94"; 43#else 44static const char rcsid[] = 45 "$FreeBSD: head/bin/rm/rm.c 51230 1999-09-13 15:12:30Z bde $"; 46#endif 47#endif /* not lint */ 48 49#include <sys/types.h> 50#include <sys/stat.h> 51#include <sys/param.h> 52#include <sys/mount.h> 53 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 <sysexits.h> 62#include <unistd.h> 63 64extern char *flags_to_string __P((u_long, char *)); 65 66int dflag, eval, fflag, iflag, Pflag, vflag, Wflag, stdin_ok; 67uid_t uid; 68 69int check __P((char *, char *, struct stat *)); 70void checkdot __P((char **)); 71void rm_file __P((char **)); 72void rm_overwrite __P((char *, struct stat *)); 73void rm_tree __P((char **)); 74void usage __P((void)); 75 76/* 77 * rm -- 78 * This rm is different from historic rm's, but is expected to match 79 * POSIX 1003.2 behavior. The most visible difference is that -f 80 * has two specific effects now, ignore non-existent files and force 81 * file removal. 82 */ 83int 84main(argc, argv) 85 int argc; 86 char *argv[]; 87{ 88 int ch, rflag; 89 90 Pflag = rflag = 0; 91 while ((ch = getopt(argc, argv, "dfiPRrvW")) != -1) 92 switch(ch) { 93 case 'd': 94 dflag = 1; 95 break; 96 case 'f': 97 fflag = 1; 98 iflag = 0; 99 break; 100 case 'i': 101 fflag = 0; 102 iflag = 1; 103 break; 104 case 'P': 105 Pflag = 1; 106 break; 107 case 'R': 108 case 'r': /* Compatibility. */ 109 rflag = 1; 110 break; 111 case 'v': 112 vflag = 1; 113 break; 114 case 'W': 115 Wflag = 1; 116 break; 117 default: 118 usage(); 119 } 120 argc -= optind; 121 argv += optind; 122 123 if (argc < 1) { 124 if (fflag) 125 return 0; 126 usage(); 127 } 128 129 checkdot(argv); 130 uid = geteuid(); 131 132 if (*argv) { 133 stdin_ok = isatty(STDIN_FILENO); 134 135 if (rflag) 136 rm_tree(argv); 137 else 138 rm_file(argv); 139 } 140 141 exit (eval); 142} 143 144void 145rm_tree(argv) 146 char **argv; 147{ 148 FTS *fts; 149 FTSENT *p; 150 int needstat; 151 int flags; 152 int rval; 153 int e; 154 155 /* 156 * Remove a file hierarchy. If forcing removal (-f), or interactive 157 * (-i) or can't ask anyway (stdin_ok), don't stat the file. 158 */ 159 needstat = !uid || (!fflag && !iflag && stdin_ok); 160 161 /* 162 * If the -i option is specified, the user can skip on the pre-order 163 * visit. The fts_number field flags skipped directories. 164 */ 165#define SKIPPED 1 166 167 flags = FTS_PHYSICAL; 168 if (!needstat) 169 flags |= FTS_NOSTAT; 170 if (Wflag) 171 flags |= FTS_WHITEOUT; 172 if (!(fts = fts_open(argv, flags, (int (*)())NULL))) 173 err(1, NULL); 174 while ((p = fts_read(fts)) != NULL) { 175 switch (p->fts_info) { 176 case FTS_DNR: 177 if (!fflag || p->fts_errno != ENOENT) { 178 warnx("%s: %s", 179 p->fts_path, strerror(p->fts_errno)); 180 eval = 1; 181 } 182 continue; 183 case FTS_ERR: 184 errx(1, "%s: %s", p->fts_path, strerror(p->fts_errno)); 185 case FTS_NS: 186 /* 187 * FTS_NS: assume that if can't stat the file, it 188 * can't be unlinked. 189 */ 190 if (!needstat) 191 break; 192 if (!fflag || p->fts_errno != ENOENT) { 193 warnx("%s: %s", 194 p->fts_path, strerror(p->fts_errno)); 195 eval = 1; 196 } 197 continue; 198 case FTS_D: 199 /* Pre-order: give user chance to skip. */ 200 if (!fflag && !check(p->fts_path, p->fts_accpath, 201 p->fts_statp)) { 202 (void)fts_set(fts, p, FTS_SKIP); 203 p->fts_number = SKIPPED; 204 } 205 else if (!uid && 206 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) && 207 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)) && 208 chflags(p->fts_accpath, 209 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)) < 0) 210 goto err; 211 continue; 212 case FTS_DP: 213 /* Post-order: see if user skipped. */ 214 if (p->fts_number == SKIPPED) 215 continue; 216 break; 217 default: 218 if (!fflag && 219 !check(p->fts_path, p->fts_accpath, p->fts_statp)) 220 continue; 221 } 222 223 rval = 0; 224 if (!uid && 225 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) && 226 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE))) 227 rval = chflags(p->fts_accpath, 228 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)); 229 if (!rval) { 230 /* 231 * If we can't read or search the directory, may still be 232 * able to remove it. Don't print out the un{read,search}able 233 * message unless the remove fails. 234 */ 235 switch (p->fts_info) { 236 case FTS_DP: 237 case FTS_DNR: 238 e = rmdir(p->fts_accpath); 239 if (e == 0 || (fflag && errno == ENOENT)) { 240 if (e == 0 && vflag) 241 (void)printf("%s\n", 242 p->fts_accpath); 243 continue; 244 } 245 break; 246 247 case FTS_W: 248 e = undelete(p->fts_accpath); 249 if (e == 0 || (fflag && errno == ENOENT)) { 250 if (e == 0 && vflag) 251 (void)printf("%s\n", 252 p->fts_accpath); 253 continue; 254 } 255 break; 256 257 default: 258 if (Pflag) 259 rm_overwrite(p->fts_accpath, NULL); 260 e = unlink(p->fts_accpath); 261 if (e == 0 || (fflag && errno == ENOENT)) { 262 if (e == 0 && vflag) 263 (void)printf("%s\n", 264 p->fts_accpath); 265 continue; 266 } 267 } 268 } 269err: 270 warn("%s", p->fts_path); 271 eval = 1; 272 } 273 if (errno) 274 err(1, "fts_read"); 275} 276 277void 278rm_file(argv) 279 char **argv; 280{ 281 struct stat sb; 282 int rval; 283 char *f; 284 285 /* 286 * Remove a file. POSIX 1003.2 states that, by default, attempting 287 * to remove a directory is an error, so must always stat the file. 288 */ 289 while ((f = *argv++) != NULL) { 290 /* Assume if can't stat the file, can't unlink it. */ 291 if (lstat(f, &sb)) { 292 if (Wflag) { 293 sb.st_mode = S_IFWHT|S_IWUSR|S_IRUSR; 294 } else { 295 if (!fflag || errno != ENOENT) { 296 warn("%s", f); 297 eval = 1; 298 } 299 continue; 300 } 301 } else if (Wflag) { 302 warnx("%s: %s", f, strerror(EEXIST)); 303 eval = 1; 304 continue; 305 } 306 307 if (S_ISDIR(sb.st_mode) && !dflag) { 308 warnx("%s: is a directory", f); 309 eval = 1; 310 continue; 311 } 312 if (!fflag && !S_ISWHT(sb.st_mode) && !check(f, f, &sb)) 313 continue; 314 rval = 0; 315 if (!uid && 316 (sb.st_flags & (UF_APPEND|UF_IMMUTABLE)) && 317 !(sb.st_flags & (SF_APPEND|SF_IMMUTABLE))) 318 rval = chflags(f, sb.st_flags & ~(UF_APPEND|UF_IMMUTABLE)); 319 if (!rval) { 320 if (S_ISWHT(sb.st_mode)) 321 rval = undelete(f); 322 else if (S_ISDIR(sb.st_mode)) 323 rval = rmdir(f); 324 else { 325 if (Pflag) 326 rm_overwrite(f, &sb); 327 rval = unlink(f); 328 } 329 } 330 if (rval && (!fflag || errno != ENOENT)) { 331 warn("%s", f); 332 eval = 1; 333 } 334 if (vflag) 335 (void)printf("%s\n", f); 336 } 337} 338 339/* 340 * rm_overwrite -- 341 * Overwrite the file 3 times with varying bit patterns. 342 * 343 * XXX 344 * This is a cheap way to *really* delete files. Note that only regular 345 * files are deleted, directories (and therefore names) will remain. 346 * Also, this assumes a fixed-block file system (like FFS, or a V7 or a 347 * System V file system). In a logging file system, you'll have to have 348 * kernel support. 349 */ 350void 351rm_overwrite(file, sbp) 352 char *file; 353 struct stat *sbp; 354{ 355 struct stat sb; 356 struct statfs fsb; 357 off_t len; 358 int bsize, fd, wlen; 359 char *buf = NULL; 360 361 fd = -1; 362 if (sbp == NULL) { 363 if (lstat(file, &sb)) 364 goto err; 365 sbp = &sb; 366 } 367 if (!S_ISREG(sbp->st_mode)) 368 return; 369 if ((fd = open(file, O_WRONLY, 0)) == -1) 370 goto err; 371 if (fstatfs(fd, &fsb) == -1) 372 goto err; 373 bsize = MAX(fsb.f_iosize, 1024); 374 if ((buf = malloc(bsize)) == NULL) 375 err(1, "malloc"); 376 377#define PASS(byte) { \ 378 memset(buf, byte, bsize); \ 379 for (len = sbp->st_size; len > 0; len -= wlen) { \ 380 wlen = len < bsize ? len : bsize; \ 381 if (write(fd, buf, wlen) != wlen) \ 382 goto err; \ 383 } \ 384} 385 PASS(0xff); 386 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 387 goto err; 388 PASS(0x00); 389 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 390 goto err; 391 PASS(0xff); 392 if (!fsync(fd) && !close(fd)) { 393 free(buf); 394 return; 395 } 396 397err: eval = 1; 398 if (buf) 399 free(buf); 400 warn("%s", file); 401} 402 403 404int 405check(path, name, sp) 406 char *path, *name; 407 struct stat *sp; 408{ 409 int ch, first; 410 char modep[15], flagsp[128]; 411 412 /* Check -i first. */ 413 if (iflag) 414 (void)fprintf(stderr, "remove %s? ", path); 415 else { 416 /* 417 * If it's not a symbolic link and it's unwritable and we're 418 * talking to a terminal, ask. Symbolic links are excluded 419 * because their permissions are meaningless. Check stdin_ok 420 * first because we may not have stat'ed the file. 421 */ 422 if (!stdin_ok || S_ISLNK(sp->st_mode) || 423 (!access(name, W_OK) && 424 !(sp->st_flags & (SF_APPEND|SF_IMMUTABLE)) && 425 (!(sp->st_flags & (UF_APPEND|UF_IMMUTABLE)) || !uid))) 426 return (1); 427 strmode(sp->st_mode, modep); 428 strcpy(flagsp, flags_to_string(sp->st_flags, NULL)); 429 if (*flagsp) 430 strcat(flagsp, " "); 431 (void)fprintf(stderr, "override %s%s%s/%s %sfor %s? ", 432 modep + 1, modep[9] == ' ' ? "" : " ", 433 user_from_uid(sp->st_uid, 0), 434 group_from_gid(sp->st_gid, 0), 435 *flagsp ? flagsp : "", 436 path); 437 } 438 (void)fflush(stderr); 439 440 first = ch = getchar(); 441 while (ch != '\n' && ch != EOF) 442 ch = getchar(); 443 return (first == 'y' || first == 'Y'); 444} 445 446#define ISDOT(a) ((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2]))) 447void 448checkdot(argv) 449 char **argv; 450{ 451 char *p, **save, **t; 452 int complained; 453 454 complained = 0; 455 for (t = argv; *t;) { 456 if ((p = strrchr(*t, '/')) != NULL) 457 ++p; 458 else 459 p = *t; 460 if (ISDOT(p)) { 461 if (!complained++) 462 warnx("\".\" and \"..\" may not be removed"); 463 eval = 1; 464 for (save = t; (t[0] = t[1]) != NULL; ++t) 465 continue; 466 t = save; 467 } else 468 ++t; 469 } 470} 471 472void 473usage() 474{ 475 (void)fprintf(stderr, "usage: rm [-f | -i] [-dPRrvW] file ...\n"); 476 exit(EX_USAGE); 477} 478