1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 28 /* All Rights Reserved */ 29 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 /* 33 * rm [-fiRr] file ... 34 */ 35 36 #include <stdio.h> 37 #include <fcntl.h> 38 #include <string.h> 39 #include <sys/types.h> 40 #include <sys/stat.h> 41 #include <dirent.h> 42 #include <limits.h> 43 #include <locale.h> 44 #include <langinfo.h> 45 #include <unistd.h> 46 #include <stdlib.h> 47 #include <errno.h> 48 #include <sys/resource.h> 49 #include <sys/avl.h> 50 #include <libcmdutils.h> 51 52 #define ARGCNT 5 /* Number of arguments */ 53 #define CHILD 0 54 #define DIRECTORY ((buffer.st_mode&S_IFMT) == S_IFDIR) 55 #define SYMLINK ((buffer.st_mode&S_IFMT) == S_IFLNK) 56 #define FAIL -1 57 #define MAXFORK 100 /* Maximum number of forking attempts */ 58 #define NAMESIZE MAXNAMLEN + 1 /* "/" + (file name size) */ 59 #define TRUE 1 60 #define FALSE 0 61 #define WRITE 02 62 #define SEARCH 07 63 64 static int errcode; 65 static int interactive, recursive, silent; /* flags for command line options */ 66 67 static void rm(char *, int); 68 static void undir(char *, int, dev_t, ino_t); 69 static int yes(void); 70 static int mypath(dev_t, ino_t); 71 72 static char yeschr[SCHAR_MAX + 2]; 73 static char nochr[SCHAR_MAX + 2]; 74 75 static char *fullpath; 76 static int homedirfd; 77 78 static void push_name(char *name, int first); 79 static void pop_name(int first); 80 static void force_chdir(char *); 81 static void ch_dir(char *); 82 static char *get_filename(char *name); 83 static void chdir_home(void); 84 static void check_homedir(void); 85 static void cleanup(void); 86 87 static char *cwd; /* pathname of home dir, from getcwd() */ 88 static rlim_t maxfiles; /* maximum number of open files */ 89 static int first_dir = 1; /* flag set when first trying to remove a dir */ 90 /* flag set when can't get dev/inode of a parent dir */ 91 static int parent_err = 0; 92 static avl_tree_t *tree; /* tree to keep track of nodes visited */ 93 94 struct dir_id { 95 dev_t dev; 96 ino_t inode; 97 struct dir_id *next; 98 }; 99 100 /* 101 * homedir is the first of a linked list of structures 102 * containing unique identifying device and inode numbers for 103 * each directory, from the home dir up to the root. 104 */ 105 static struct dir_id homedir; 106 107 int 108 main(int argc, char *argv[]) 109 { 110 extern int optind; 111 int errflg = 0; 112 int c; 113 struct rlimit rl; 114 115 (void) setlocale(LC_ALL, ""); 116 #if !defined(TEXT_DOMAIN) /* Should be defined by cc -D */ 117 #define TEXT_DOMAIN "SYS_TEST" /* Use this only if it weren't */ 118 #endif 119 (void) textdomain(TEXT_DOMAIN); 120 121 (void) strncpy(yeschr, nl_langinfo(YESSTR), SCHAR_MAX + 1); 122 (void) strncpy(nochr, nl_langinfo(NOSTR), SCHAR_MAX + 1); 123 124 while ((c = getopt(argc, argv, "frRi")) != EOF) 125 switch (c) { 126 case 'f': 127 silent = TRUE; 128 #ifdef XPG4 129 interactive = FALSE; 130 #endif 131 break; 132 case 'i': 133 interactive = TRUE; 134 #ifdef XPG4 135 silent = FALSE; 136 #endif 137 break; 138 case 'r': 139 case 'R': 140 recursive = TRUE; 141 break; 142 case '?': 143 errflg = 1; 144 break; 145 } 146 147 /* 148 * For BSD compatibility allow '-' to delimit the end 149 * of options. However, if options were already explicitly 150 * terminated with '--', then treat '-' literally: otherwise, 151 * "rm -- -" won't remove '-'. 152 */ 153 if (optind < argc && 154 strcmp(argv[optind], "-") == 0 && 155 strcmp(argv[optind - 1], "--") != 0) 156 optind++; 157 158 argc -= optind; 159 argv = &argv[optind]; 160 161 if ((argc < 1 && !silent) || errflg) { 162 (void) fprintf(stderr, 163 gettext("usage: rm [-fiRr] file ...\n")); 164 exit(2); 165 } 166 167 if (getrlimit(RLIMIT_NOFILE, &rl)) { 168 perror("getrlimit"); 169 exit(2); 170 } else 171 maxfiles = rl.rlim_cur - 2; 172 173 while (argc-- > 0) { 174 tree = NULL; 175 rm(*argv, 1); 176 argv++; 177 destroy_tree(tree); 178 } 179 cleanup(); 180 return (errcode ? 2 : 0); 181 /* NOTREACHED */ 182 } 183 184 static void 185 rm(char *path, int first) 186 { 187 struct stat buffer; 188 char *filepath; 189 char *p; 190 char resolved_path[PATH_MAX]; 191 192 /* 193 * Check file to see if it exists. 194 */ 195 if (lstat(path, &buffer) == FAIL) { 196 if (!silent) { 197 perror(path); 198 ++errcode; 199 } 200 return; 201 } 202 203 /* prevent removal of / but allow removal of sym-links */ 204 if (!S_ISLNK(buffer.st_mode) && realpath(path, resolved_path) != NULL && 205 strcmp(resolved_path, "/") == 0) { 206 (void) fprintf(stderr, 207 gettext("rm of %s is not allowed\n"), resolved_path); 208 errcode++; 209 return; 210 } 211 212 /* prevent removal of . or .. (directly) */ 213 if (p = strrchr(path, '/')) 214 p++; 215 else 216 p = path; 217 if (strcmp(".", p) == 0 || strcmp("..", p) == 0) { 218 (void) fprintf(stderr, 219 gettext("rm of %s is not allowed\n"), path); 220 errcode++; 221 return; 222 } 223 /* 224 * If it's a directory, remove its contents. 225 */ 226 if (DIRECTORY) { 227 /* 228 * If "-r" wasn't specified, trying to remove directories 229 * is an error. 230 */ 231 if (!recursive) { 232 (void) fprintf(stderr, 233 gettext("rm: %s is a directory\n"), path); 234 ++errcode; 235 return; 236 } 237 238 if (first_dir) { 239 check_homedir(); 240 first_dir = 0; 241 } 242 243 undir(path, first, buffer.st_dev, buffer.st_ino); 244 return; 245 } 246 filepath = get_filename(path); 247 248 /* 249 * If interactive, ask for acknowledgement. 250 * 251 * TRANSLATION_NOTE - The following message will contain the 252 * first character of the strings for "yes" and "no" defined 253 * in the file "nl_langinfo.po". After substitution, the 254 * message will appear as follows: 255 * rm: remove <filename> (y/n)? 256 * For example, in German, this will appear as 257 * rm: l�schen <filename> (j/n)? 258 * where j=ja, n=nein, <filename>=the file to be removed 259 * 260 */ 261 262 263 if (interactive) { 264 (void) fprintf(stderr, gettext("rm: remove %s (%s/%s)? "), 265 filepath, yeschr, nochr); 266 if (!yes()) { 267 free(filepath); 268 return; 269 } 270 } else if (!silent) { 271 /* 272 * If not silent, and stdin is a terminal, and there's 273 * no write access, and the file isn't a symbolic link, 274 * ask for permission. 275 * 276 * TRANSLATION_NOTE - The following message will contain the 277 * first character of the strings for "yes" and "no" defined 278 * in the file "nl_langinfo.po". After substitution, the 279 * message will appear as follows: 280 * rm: <filename>: override protection XXX (y/n)? 281 * where XXX is the permission mode bits of the file in octal 282 * and <filename> is the file to be removed 283 * 284 */ 285 if (!SYMLINK && access(path, W_OK) == FAIL && 286 isatty(fileno(stdin))) { 287 (void) printf( 288 gettext("rm: %s: override protection %o (%s/%s)? "), 289 filepath, buffer.st_mode & 0777, yeschr, nochr); 290 /* 291 * If permission isn't given, skip the file. 292 */ 293 if (!yes()) { 294 free(filepath); 295 return; 296 } 297 } 298 } 299 300 /* 301 * If the unlink fails, inform the user. For /usr/bin/rm, only inform 302 * the user if interactive or not silent. 303 * If unlink fails with errno = ENOENT because file was removed 304 * in between the lstat call and unlink don't inform the user and 305 * don't change errcode. 306 */ 307 308 if (unlink(path) == FAIL) { 309 if (errno == ENOENT) { 310 free(filepath); 311 return; 312 } 313 #ifndef XPG4 314 if (!silent || interactive) { 315 #endif 316 (void) fprintf(stderr, 317 gettext("rm: %s not removed: "), filepath); 318 perror(""); 319 #ifndef XPG4 320 } 321 #endif 322 ++errcode; 323 } 324 325 free(filepath); 326 } 327 328 static void 329 undir(char *path, int first, dev_t dev, ino_t ino) 330 { 331 char *newpath; 332 DIR *name; 333 struct dirent *direct; 334 int ismypath; 335 int ret; 336 int chdir_failed = 0; 337 size_t len; 338 339 push_name(path, first); 340 341 /* 342 * If interactive and this file isn't in the path of the 343 * current working directory, ask for acknowledgement. 344 * 345 * TRANSLATION_NOTE - The following message will contain the 346 * first character of the strings for "yes" and "no" defined 347 * in the file "nl_langinfo.po". After substitution, the 348 * message will appear as follows: 349 * rm: examine files in directory <directoryname> (y/n)? 350 * where <directoryname> is the directory to be removed 351 * 352 */ 353 ismypath = mypath(dev, ino); 354 if (interactive) { 355 (void) fprintf(stderr, 356 gettext("rm: examine files in directory %s (%s/%s)? "), 357 fullpath, yeschr, nochr); 358 /* 359 * If the answer is no, skip the directory. 360 */ 361 if (!yes()) { 362 pop_name(first); 363 return; 364 } 365 } 366 367 #ifdef XPG4 368 /* 369 * XCU4 and POSIX.2: If not interactive and file is not in the 370 * path of the current working directory, check to see whether 371 * or not directory is readable or writable and if not, 372 * prompt user for response. 373 */ 374 if (!interactive && !ismypath && 375 (access(path, W_OK|X_OK) == FAIL) && isatty(fileno(stdin))) { 376 if (!silent) { 377 (void) fprintf(stderr, 378 gettext( 379 "rm: examine files in directory %s (%s/%s)? "), 380 fullpath, yeschr, nochr); 381 /* 382 * If the answer is no, skip the directory. 383 */ 384 if (!yes()) { 385 pop_name(first); 386 return; 387 } 388 } 389 } 390 #endif 391 392 /* 393 * Add this node to the search tree so we don't 394 * get into a endless loop. If the add fails then 395 * we have visited this node before. 396 */ 397 ret = add_tnode(&tree, dev, ino); 398 if (ret != 1) { 399 if (ret == 0) { 400 (void) fprintf(stderr, 401 gettext("rm: cycle detected for %s\n"), 402 fullpath); 403 } else if (ret == -1) { 404 perror("rm"); 405 } 406 errcode++; 407 pop_name(first); 408 return; 409 } 410 411 /* 412 * Open the directory for reading. 413 */ 414 if ((name = opendir(path)) == NULL) { 415 int saveerrno = errno; 416 417 /* 418 * If interactive, ask for acknowledgement. 419 */ 420 if (interactive) { 421 /* 422 * Print an error message that 423 * we could not read the directory 424 * as the user wanted to examine 425 * files in the directory. Only 426 * affect the error status if 427 * user doesn't want to remove the 428 * directory as we still may be able 429 * remove the directory successfully. 430 */ 431 (void) fprintf(stderr, gettext( 432 "rm: cannot read directory %s: "), 433 fullpath); 434 errno = saveerrno; 435 perror(""); 436 (void) fprintf(stderr, gettext( 437 "rm: remove %s: (%s/%s)? "), 438 fullpath, yeschr, nochr); 439 if (!yes()) { 440 ++errcode; 441 pop_name(first); 442 return; 443 } 444 } 445 446 /* 447 * If the directory is empty, we may be able to 448 * go ahead and remove it. 449 */ 450 if (rmdir(path) == FAIL) { 451 if (interactive) { 452 int rmdirerr = errno; 453 (void) fprintf(stderr, gettext( 454 "rm: Unable to remove directory %s: "), 455 fullpath); 456 errno = rmdirerr; 457 perror(""); 458 } else { 459 (void) fprintf(stderr, gettext( 460 "rm: cannot read directory %s: "), 461 fullpath); 462 errno = saveerrno; 463 perror(""); 464 } 465 ++errcode; 466 } 467 468 /* Continue to next file/directory rather than exit */ 469 pop_name(first); 470 return; 471 } 472 473 /* 474 * XCU4 requires that rm -r descend the directory 475 * hierarchy without regard to PATH_MAX. If we can't 476 * chdir() do not increment error counter and do not 477 * print message. 478 * 479 * However, if we cannot chdir because someone has taken away 480 * execute access we may still be able to delete the directory 481 * if it's empty. The old rm could do this. 482 */ 483 484 if (chdir(path) == -1) { 485 chdir_failed = 1; 486 } 487 488 /* 489 * Read every directory entry. 490 */ 491 while ((direct = readdir(name)) != NULL) { 492 /* 493 * Ignore "." and ".." entries. 494 */ 495 if (strcmp(direct->d_name, ".") == 0 || 496 strcmp(direct->d_name, "..") == 0) 497 continue; 498 /* 499 * Try to remove the file. 500 */ 501 len = strlen(direct->d_name) + 1; 502 if (chdir_failed) { 503 len += strlen(path) + 2; 504 } 505 506 newpath = malloc(len); 507 if (newpath == NULL) { 508 (void) fprintf(stderr, 509 gettext("rm: Insufficient memory.\n")); 510 cleanup(); 511 exit(1); 512 } 513 514 if (!chdir_failed) { 515 (void) strcpy(newpath, direct->d_name); 516 } else { 517 (void) snprintf(newpath, len, "%s/%s", 518 path, direct->d_name); 519 } 520 521 522 /* 523 * If a spare file descriptor is available, just call the 524 * "rm" function with the file name; otherwise close the 525 * directory and reopen it when the child is removed. 526 */ 527 if (name->dd_fd >= maxfiles) { 528 (void) closedir(name); 529 rm(newpath, 0); 530 if (!chdir_failed) 531 name = opendir("."); 532 else 533 name = opendir(path); 534 if (name == NULL) { 535 (void) fprintf(stderr, 536 gettext("rm: cannot read directory %s: "), 537 fullpath); 538 perror(""); 539 cleanup(); 540 exit(2); 541 } 542 } else 543 rm(newpath, 0); 544 545 free(newpath); 546 } 547 548 /* 549 * Close the directory we just finished reading. 550 */ 551 (void) closedir(name); 552 553 /* 554 * The contents of the directory have been removed. If the 555 * directory itself is in the path of the current working 556 * directory, don't try to remove it. 557 * When the directory itself is the current working directory, mypath() 558 * has a return code == 2. 559 * 560 * XCU4: Because we've descended the directory hierarchy in order 561 * to avoid PATH_MAX limitation, we must now start ascending 562 * one level at a time and remove files/directories. 563 */ 564 565 if (!chdir_failed) { 566 if (first) 567 chdir_home(); 568 else if (chdir("..") == -1) { 569 (void) fprintf(stderr, 570 gettext("rm: cannot change to parent of " 571 "directory %s: "), 572 fullpath); 573 perror(""); 574 cleanup(); 575 exit(2); 576 } 577 } 578 579 switch (ismypath) { 580 case 3: 581 pop_name(first); 582 return; 583 case 2: 584 (void) fprintf(stderr, 585 gettext("rm: Cannot remove any directory in the path " 586 "of the current working directory\n%s\n"), fullpath); 587 ++errcode; 588 pop_name(first); 589 return; 590 case 1: 591 ++errcode; 592 pop_name(first); 593 return; 594 case 0: 595 break; 596 } 597 598 /* 599 * If interactive, ask for acknowledgement. 600 */ 601 if (interactive) { 602 (void) fprintf(stderr, gettext("rm: remove %s: (%s/%s)? "), 603 fullpath, yeschr, nochr); 604 if (!yes()) { 605 pop_name(first); 606 return; 607 } 608 } 609 if (rmdir(path) == FAIL) { 610 (void) fprintf(stderr, 611 gettext("rm: Unable to remove directory %s: "), 612 fullpath); 613 perror(""); 614 ++errcode; 615 } 616 pop_name(first); 617 } 618 619 620 static int 621 yes(void) 622 { 623 int i, b; 624 char ans[SCHAR_MAX + 1]; 625 626 for (i = 0; ; i++) { 627 b = getchar(); 628 if (b == '\n' || b == '\0' || b == EOF) { 629 ans[i] = 0; 630 break; 631 } 632 if (i < SCHAR_MAX) 633 ans[i] = b; 634 } 635 if (i >= SCHAR_MAX) { 636 i = SCHAR_MAX; 637 ans[SCHAR_MAX] = 0; 638 } 639 if ((i == 0) | (strncmp(yeschr, ans, i))) 640 return (0); 641 return (1); 642 } 643 644 645 static int 646 mypath(dev_t dev, ino_t ino) 647 { 648 struct dir_id *curdir; 649 650 /* 651 * Check to see if this is our current directory 652 * Indicated by return 2; 653 */ 654 if (dev == homedir.dev && ino == homedir.inode) { 655 return (2); 656 } 657 658 curdir = homedir.next; 659 660 while (curdir != NULL) { 661 /* 662 * If we find a match, the directory (dev, ino) passed to 663 * mypath() is an ancestor of ours. Indicated by return 3. 664 */ 665 if (curdir->dev == dev && curdir->inode == ino) 666 return (3); 667 curdir = curdir->next; 668 } 669 /* 670 * parent_err indicates we couldn't stat or chdir to 671 * one of our parent dirs, so the linked list of dir_id structs 672 * is incomplete 673 */ 674 if (parent_err) { 675 #ifndef XPG4 676 if (!silent || interactive) { 677 #endif 678 (void) fprintf(stderr, gettext("rm: cannot determine " 679 "if this is an ancestor of the current " 680 "working directory\n%s\n"), fullpath); 681 #ifndef XPG4 682 } 683 #endif 684 /* assume it is. least dangerous */ 685 return (1); 686 } 687 return (0); 688 } 689 690 static int maxlen; 691 static int curlen; 692 693 static char * 694 get_filename(char *name) 695 { 696 char *path; 697 size_t len; 698 699 if (fullpath == NULL || *fullpath == '\0') { 700 path = strdup(name); 701 if (path == NULL) { 702 (void) fprintf(stderr, 703 gettext("rm: Insufficient memory.\n")); 704 cleanup(); 705 exit(1); 706 } 707 } else { 708 len = strlen(fullpath) + strlen(name) + 2; 709 path = malloc(len); 710 if (path == NULL) { 711 (void) fprintf(stderr, 712 gettext("rm: Insufficient memory.\n")); 713 cleanup(); 714 exit(1); 715 } 716 (void) snprintf(path, len, "%s/%s", fullpath, name); 717 } 718 return (path); 719 } 720 721 static void 722 push_name(char *name, int first) 723 { 724 int namelen; 725 726 namelen = strlen(name) + 1; /* 1 for "/" */ 727 if ((curlen + namelen) >= maxlen) { 728 maxlen += PATH_MAX; 729 fullpath = (char *)realloc(fullpath, (size_t)(maxlen + 1)); 730 } 731 if (first) { 732 (void) strcpy(fullpath, name); 733 } else { 734 (void) strcat(fullpath, "/"); 735 (void) strcat(fullpath, name); 736 } 737 curlen = strlen(fullpath); 738 } 739 740 static void 741 pop_name(int first) 742 { 743 char *slash; 744 if (first) { 745 *fullpath = '\0'; 746 return; 747 } 748 slash = strrchr(fullpath, '/'); 749 if (slash) 750 *slash = '\0'; 751 else 752 *fullpath = '\0'; 753 curlen = strlen(fullpath); 754 } 755 756 static void 757 force_chdir(char *dirname) 758 { 759 char *pathname, *mp, *tp; 760 761 /* use pathname instead of dirname, so dirname won't be modified */ 762 if ((pathname = strdup(dirname)) == NULL) { 763 (void) fprintf(stderr, gettext("rm: strdup: ")); 764 perror(""); 765 cleanup(); 766 exit(2); 767 } 768 769 /* pathname is an absolute full path from getcwd() */ 770 mp = pathname; 771 while (mp) { 772 tp = strchr(mp, '/'); 773 if (strlen(mp) >= PATH_MAX) { 774 /* 775 * after the first iteration through this 776 * loop, the below will NULL out the '/' 777 * which follows the first dir on pathname 778 */ 779 *tp = 0; 780 tp++; 781 if (*mp == NULL) 782 ch_dir("/"); 783 else 784 /* 785 * mp points to the start of a dirname, 786 * terminated by NULL, so ch_dir() 787 * here will move down one directory 788 */ 789 ch_dir(mp); 790 /* 791 * reset mp to the start of the dirname 792 * which follows the one we just chdir'd to 793 */ 794 mp = tp; 795 continue; /* probably can remove this */ 796 } else { 797 ch_dir(mp); 798 break; 799 } 800 } 801 free(pathname); 802 } 803 804 static void 805 ch_dir(char *dirname) 806 { 807 if (chdir(dirname) == -1) { 808 (void) fprintf(stderr, 809 gettext("rm: cannot change to %s directory: "), dirname); 810 perror(""); 811 cleanup(); 812 exit(2); 813 } 814 } 815 816 static void 817 chdir_home(void) 818 { 819 /* 820 * Go back to home dir--the dir from where rm was executed--using 821 * one of two methods, depending on which method works 822 * for the given permissions of the home dir and its 823 * parent directories. 824 */ 825 if (homedirfd != -1) { 826 if (fchdir(homedirfd) == -1) { 827 (void) fprintf(stderr, 828 gettext("rm: cannot change to starting " 829 "directory: ")); 830 perror(""); 831 cleanup(); 832 exit(2); 833 } 834 } else { 835 if (strlen(cwd) < PATH_MAX) 836 ch_dir(cwd); 837 else 838 force_chdir(cwd); 839 } 840 } 841 842 /* 843 * check_homedir - 844 * is only called the first time rm tries to 845 * remove a directory. It saves the current directory, i.e., 846 * home dir, so we can go back to it after traversing elsewhere. 847 * It also saves all the device and inode numbers of each 848 * dir from the home dir back to the root in a linked list, so we 849 * can later check, via mypath(), if we are trying to remove our current 850 * dir or an ancestor. 851 */ 852 static void 853 check_homedir(void) 854 { 855 int size; /* size allocated for pathname of home dir (cwd) */ 856 struct stat buffer; 857 struct dir_id *lastdir, *curdir; 858 859 /* 860 * We need to save where we currently are (the "home dir") so 861 * we can return after traversing down directories we're 862 * removing. Two methods are attempted: 863 * 864 * 1) open() the home dir so we can use the fd 865 * to fchdir() back. This requires read permission 866 * on the home dir. 867 * 868 * 2) getcwd() so we can chdir() to go back. This 869 * requires search (x) permission on the home dir, 870 * and read and search permission on all parent dirs. Also, 871 * getcwd() will not work if the home dir is > 341 872 * directories deep (see open bugid 4033182 - getcwd needs 873 * to work for pathnames of any depth). 874 * 875 * If neither method works, we can't remove any directories 876 * and rm will fail. 877 * 878 * For future enhancement, a possible 3rd option to use 879 * would be to fork a process to remove a directory, 880 * eliminating the need to chdir back to the home directory 881 * and eliminating the permission restrictions on the home dir 882 * or its parent dirs. 883 */ 884 homedirfd = open(".", O_RDONLY); 885 if (homedirfd == -1) { 886 size = PATH_MAX; 887 while ((cwd = getcwd(NULL, size)) == NULL) { 888 if (errno == ERANGE) { 889 size = PATH_MAX + size; 890 continue; 891 } else { 892 (void) fprintf(stderr, 893 gettext("rm: cannot open starting " 894 "directory: ")); 895 perror("pwd"); 896 exit(2); 897 } 898 } 899 } 900 901 /* 902 * since we exit on error here, we're guaranteed to at least 903 * have info in the first dir_id struct, homedir 904 */ 905 if (stat(".", &buffer) == -1) { 906 (void) fprintf(stderr, 907 gettext("rm: cannot stat current directory: ")); 908 perror(""); 909 exit(2); 910 } 911 homedir.dev = buffer.st_dev; 912 homedir.inode = buffer.st_ino; 913 homedir.next = NULL; 914 915 lastdir = &homedir; 916 /* 917 * Starting from current working directory, walk toward the 918 * root, looking at each directory along the way. 919 */ 920 for (;;) { 921 if (chdir("..") == -1 || lstat(".", &buffer) == -1) { 922 parent_err = 1; 923 break; 924 } 925 926 if ((lastdir->next = malloc(sizeof (struct dir_id))) == 927 NULL) { 928 (void) fprintf(stderr, 929 gettext("rm: Insufficient memory.\n")); 930 cleanup(); 931 exit(1); 932 } 933 934 curdir = lastdir->next; 935 curdir->dev = buffer.st_dev; 936 curdir->inode = buffer.st_ino; 937 curdir->next = NULL; 938 939 /* 940 * Stop when we reach the root; note that chdir("..") 941 * at the root dir will stay in root. Get rid of 942 * the redundant dir_id struct for root. 943 */ 944 if (curdir->dev == lastdir->dev && curdir->inode == 945 lastdir->inode) { 946 lastdir->next = NULL; 947 free(curdir); 948 break; 949 } 950 951 /* loop again to go back another level */ 952 lastdir = curdir; 953 } 954 /* go back to home directory */ 955 chdir_home(); 956 } 957 958 /* 959 * cleanup the dynamically-allocated list of device numbers and inodes, 960 * if any. If homedir was never used, it is external and static so 961 * it is guaranteed initialized to zero, thus homedir.next would be NULL. 962 */ 963 964 static void 965 cleanup(void) { 966 struct dir_id *lastdir, *curdir; 967 968 curdir = homedir.next; 969 970 while (curdir != NULL) { 971 lastdir = curdir; 972 curdir = curdir->next; 973 free(lastdir); 974 } 975 } 976