1 /*- 2 * Copyright (c) 1990, 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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * 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 * $OpenBSD: fts.c,v 1.22 1999/10/03 19:22:22 millert Exp $ 34 */ 35 36 #if defined(LIBC_SCCS) && !defined(lint) 37 static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94"; 38 #endif /* LIBC_SCCS and not lint */ 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 #include "namespace.h" 43 #include <sys/types.h> 44 #include <sys/param.h> 45 #include <sys/stat.h> 46 47 #include <dirent.h> 48 #include <errno.h> 49 #include <fcntl.h> 50 #include <fts.h> 51 #include <stdlib.h> 52 #include <string.h> 53 #include <unistd.h> 54 #include "un-namespace.h" 55 56 static FTSENT *fts_alloc(FTS *, char *, int); 57 static FTSENT *fts_build(FTS *, int); 58 static void fts_lfree(FTSENT *); 59 static void fts_load(FTS *, FTSENT *); 60 static size_t fts_maxarglen(char * const *); 61 static void fts_padjust(FTS *, FTSENT *); 62 static int fts_palloc(FTS *, size_t); 63 static FTSENT *fts_sort(FTS *, FTSENT *, int); 64 static u_short fts_stat(FTS *, FTSENT *, int); 65 static int fts_safe_changedir(FTS *, FTSENT *, int, char *); 66 67 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2]))) 68 69 #define CLR(opt) (sp->fts_options &= ~(opt)) 70 #define ISSET(opt) (sp->fts_options & (opt)) 71 #define SET(opt) (sp->fts_options |= (opt)) 72 73 #define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) && fchdir(fd)) 74 75 /* fts_build flags */ 76 #define BCHILD 1 /* fts_children */ 77 #define BNAMES 2 /* fts_children, names only */ 78 #define BREAD 3 /* fts_read */ 79 80 FTS * 81 fts_open(argv, options, compar) 82 char * const *argv; 83 int options; 84 int (*compar)(const FTSENT * const *, const FTSENT * const *); 85 { 86 FTS *sp; 87 FTSENT *p, *root; 88 int nitems; 89 FTSENT *parent, *tmp; 90 int len; 91 92 /* Options check. */ 93 if (options & ~FTS_OPTIONMASK) { 94 errno = EINVAL; 95 return (NULL); 96 } 97 98 /* Allocate/initialize the stream */ 99 if ((sp = malloc(sizeof(FTS))) == NULL) 100 return (NULL); 101 memset(sp, 0, sizeof(FTS)); 102 sp->fts_compar = compar; 103 sp->fts_options = options; 104 105 /* Shush, GCC. */ 106 tmp = NULL; 107 108 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 109 if (ISSET(FTS_LOGICAL)) 110 SET(FTS_NOCHDIR); 111 112 /* 113 * Start out with 1K of path space, and enough, in any case, 114 * to hold the user's paths. 115 */ 116 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN))) 117 goto mem1; 118 119 /* Allocate/initialize root's parent. */ 120 if ((parent = fts_alloc(sp, "", 0)) == NULL) 121 goto mem2; 122 parent->fts_level = FTS_ROOTPARENTLEVEL; 123 124 /* Allocate/initialize root(s). */ 125 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) { 126 /* Don't allow zero-length paths. */ 127 if ((len = strlen(*argv)) == 0) { 128 errno = ENOENT; 129 goto mem3; 130 } 131 132 p = fts_alloc(sp, *argv, len); 133 p->fts_level = FTS_ROOTLEVEL; 134 p->fts_parent = parent; 135 p->fts_accpath = p->fts_name; 136 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 137 138 /* Command-line "." and ".." are real directories. */ 139 if (p->fts_info == FTS_DOT) 140 p->fts_info = FTS_D; 141 142 /* 143 * If comparison routine supplied, traverse in sorted 144 * order; otherwise traverse in the order specified. 145 */ 146 if (compar) { 147 p->fts_link = root; 148 root = p; 149 } else { 150 p->fts_link = NULL; 151 if (root == NULL) 152 tmp = root = p; 153 else { 154 tmp->fts_link = p; 155 tmp = p; 156 } 157 } 158 } 159 if (compar && nitems > 1) 160 root = fts_sort(sp, root, nitems); 161 162 /* 163 * Allocate a dummy pointer and make fts_read think that we've just 164 * finished the node before the root(s); set p->fts_info to FTS_INIT 165 * so that everything about the "current" node is ignored. 166 */ 167 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 168 goto mem3; 169 sp->fts_cur->fts_link = root; 170 sp->fts_cur->fts_info = FTS_INIT; 171 172 /* 173 * If using chdir(2), grab a file descriptor pointing to dot to ensure 174 * that we can get back here; this could be avoided for some paths, 175 * but almost certainly not worth the effort. Slashes, symbolic links, 176 * and ".." are all fairly nasty problems. Note, if we can't get the 177 * descriptor we run anyway, just more slowly. 178 */ 179 if (!ISSET(FTS_NOCHDIR) && (sp->fts_rfd = _open(".", O_RDONLY, 0)) < 0) 180 SET(FTS_NOCHDIR); 181 182 return (sp); 183 184 mem3: fts_lfree(root); 185 free(parent); 186 mem2: free(sp->fts_path); 187 mem1: free(sp); 188 return (NULL); 189 } 190 191 static void 192 fts_load(sp, p) 193 FTS *sp; 194 FTSENT *p; 195 { 196 int len; 197 char *cp; 198 199 /* 200 * Load the stream structure for the next traversal. Since we don't 201 * actually enter the directory until after the preorder visit, set 202 * the fts_accpath field specially so the chdir gets done to the right 203 * place and the user can access the first node. From fts_open it's 204 * known that the path will fit. 205 */ 206 len = p->fts_pathlen = p->fts_namelen; 207 memmove(sp->fts_path, p->fts_name, len + 1); 208 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 209 len = strlen(++cp); 210 memmove(p->fts_name, cp, len + 1); 211 p->fts_namelen = len; 212 } 213 p->fts_accpath = p->fts_path = sp->fts_path; 214 sp->fts_dev = p->fts_dev; 215 } 216 217 int 218 fts_close(sp) 219 FTS *sp; 220 { 221 FTSENT *freep, *p; 222 int saved_errno; 223 224 /* 225 * This still works if we haven't read anything -- the dummy structure 226 * points to the root list, so we step through to the end of the root 227 * list which has a valid parent pointer. 228 */ 229 if (sp->fts_cur) { 230 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 231 freep = p; 232 p = p->fts_link != NULL ? p->fts_link : p->fts_parent; 233 free(freep); 234 } 235 free(p); 236 } 237 238 /* Free up child linked list, sort array, path buffer. */ 239 if (sp->fts_child) 240 fts_lfree(sp->fts_child); 241 if (sp->fts_array) 242 free(sp->fts_array); 243 free(sp->fts_path); 244 245 /* Return to original directory, save errno if necessary. */ 246 if (!ISSET(FTS_NOCHDIR)) { 247 saved_errno = fchdir(sp->fts_rfd) ? errno : 0; 248 (void)_close(sp->fts_rfd); 249 250 /* Set errno and return. */ 251 if (saved_errno != 0) { 252 /* Free up the stream pointer. */ 253 free(sp); 254 errno = saved_errno; 255 return (-1); 256 } 257 } 258 259 /* Free up the stream pointer. */ 260 free(sp); 261 return (0); 262 } 263 264 /* 265 * Special case of "/" at the end of the path so that slashes aren't 266 * appended which would cause paths to be written as "....//foo". 267 */ 268 #define NAPPEND(p) \ 269 (p->fts_path[p->fts_pathlen - 1] == '/' \ 270 ? p->fts_pathlen - 1 : p->fts_pathlen) 271 272 FTSENT * 273 fts_read(sp) 274 FTS *sp; 275 { 276 FTSENT *p, *tmp; 277 int instr; 278 char *t; 279 int saved_errno; 280 281 /* If finished or unrecoverable error, return NULL. */ 282 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 283 return (NULL); 284 285 /* Set current node pointer. */ 286 p = sp->fts_cur; 287 288 /* Save and zero out user instructions. */ 289 instr = p->fts_instr; 290 p->fts_instr = FTS_NOINSTR; 291 292 /* Any type of file may be re-visited; re-stat and re-turn. */ 293 if (instr == FTS_AGAIN) { 294 p->fts_info = fts_stat(sp, p, 0); 295 return (p); 296 } 297 298 /* 299 * Following a symlink -- SLNONE test allows application to see 300 * SLNONE and recover. If indirecting through a symlink, have 301 * keep a pointer to current location. If unable to get that 302 * pointer, follow fails. 303 */ 304 if (instr == FTS_FOLLOW && 305 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 306 p->fts_info = fts_stat(sp, p, 1); 307 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 308 if ((p->fts_symfd = _open(".", O_RDONLY, 0)) < 0) { 309 p->fts_errno = errno; 310 p->fts_info = FTS_ERR; 311 } else 312 p->fts_flags |= FTS_SYMFOLLOW; 313 } 314 return (p); 315 } 316 317 /* Directory in pre-order. */ 318 if (p->fts_info == FTS_D) { 319 /* If skipped or crossed mount point, do post-order visit. */ 320 if (instr == FTS_SKIP || 321 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) { 322 if (p->fts_flags & FTS_SYMFOLLOW) 323 (void)_close(p->fts_symfd); 324 if (sp->fts_child) { 325 fts_lfree(sp->fts_child); 326 sp->fts_child = NULL; 327 } 328 p->fts_info = FTS_DP; 329 return (p); 330 } 331 332 /* Rebuild if only read the names and now traversing. */ 333 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) { 334 CLR(FTS_NAMEONLY); 335 fts_lfree(sp->fts_child); 336 sp->fts_child = NULL; 337 } 338 339 /* 340 * Cd to the subdirectory. 341 * 342 * If have already read and now fail to chdir, whack the list 343 * to make the names come out right, and set the parent errno 344 * so the application will eventually get an error condition. 345 * Set the FTS_DONTCHDIR flag so that when we logically change 346 * directories back to the parent we don't do a chdir. 347 * 348 * If haven't read do so. If the read fails, fts_build sets 349 * FTS_STOP or the fts_info field of the node. 350 */ 351 if (sp->fts_child != NULL) { 352 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) { 353 p->fts_errno = errno; 354 p->fts_flags |= FTS_DONTCHDIR; 355 for (p = sp->fts_child; p != NULL; 356 p = p->fts_link) 357 p->fts_accpath = 358 p->fts_parent->fts_accpath; 359 } 360 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 361 if (ISSET(FTS_STOP)) 362 return (NULL); 363 return (p); 364 } 365 p = sp->fts_child; 366 sp->fts_child = NULL; 367 goto name; 368 } 369 370 /* Move to the next node on this level. */ 371 next: tmp = p; 372 if ((p = p->fts_link) != NULL) { 373 free(tmp); 374 375 /* 376 * If reached the top, return to the original directory (or 377 * the root of the tree), and load the paths for the next root. 378 */ 379 if (p->fts_level == FTS_ROOTLEVEL) { 380 if (FCHDIR(sp, sp->fts_rfd)) { 381 SET(FTS_STOP); 382 return (NULL); 383 } 384 fts_load(sp, p); 385 return (sp->fts_cur = p); 386 } 387 388 /* 389 * User may have called fts_set on the node. If skipped, 390 * ignore. If followed, get a file descriptor so we can 391 * get back if necessary. 392 */ 393 if (p->fts_instr == FTS_SKIP) 394 goto next; 395 if (p->fts_instr == FTS_FOLLOW) { 396 p->fts_info = fts_stat(sp, p, 1); 397 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 398 if ((p->fts_symfd = 399 _open(".", O_RDONLY, 0)) < 0) { 400 p->fts_errno = errno; 401 p->fts_info = FTS_ERR; 402 } else 403 p->fts_flags |= FTS_SYMFOLLOW; 404 } 405 p->fts_instr = FTS_NOINSTR; 406 } 407 408 name: t = sp->fts_path + NAPPEND(p->fts_parent); 409 *t++ = '/'; 410 memmove(t, p->fts_name, p->fts_namelen + 1); 411 return (sp->fts_cur = p); 412 } 413 414 /* Move up to the parent node. */ 415 p = tmp->fts_parent; 416 free(tmp); 417 418 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 419 /* 420 * Done; free everything up and set errno to 0 so the user 421 * can distinguish between error and EOF. 422 */ 423 free(p); 424 errno = 0; 425 return (sp->fts_cur = NULL); 426 } 427 428 /* NUL terminate the pathname. */ 429 sp->fts_path[p->fts_pathlen] = '\0'; 430 431 /* 432 * Return to the parent directory. If at a root node or came through 433 * a symlink, go back through the file descriptor. Otherwise, cd up 434 * one directory. 435 */ 436 if (p->fts_level == FTS_ROOTLEVEL) { 437 if (FCHDIR(sp, sp->fts_rfd)) { 438 SET(FTS_STOP); 439 return (NULL); 440 } 441 } else if (p->fts_flags & FTS_SYMFOLLOW) { 442 if (FCHDIR(sp, p->fts_symfd)) { 443 saved_errno = errno; 444 (void)_close(p->fts_symfd); 445 errno = saved_errno; 446 SET(FTS_STOP); 447 return (NULL); 448 } 449 (void)_close(p->fts_symfd); 450 } else if (!(p->fts_flags & FTS_DONTCHDIR) && 451 fts_safe_changedir(sp, p->fts_parent, -1, "..")) { 452 SET(FTS_STOP); 453 return (NULL); 454 } 455 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 456 return (sp->fts_cur = p); 457 } 458 459 /* 460 * Fts_set takes the stream as an argument although it's not used in this 461 * implementation; it would be necessary if anyone wanted to add global 462 * semantics to fts using fts_set. An error return is allowed for similar 463 * reasons. 464 */ 465 /* ARGSUSED */ 466 int 467 fts_set(sp, p, instr) 468 FTS *sp; 469 FTSENT *p; 470 int instr; 471 { 472 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW && 473 instr != FTS_NOINSTR && instr != FTS_SKIP) { 474 errno = EINVAL; 475 return (1); 476 } 477 p->fts_instr = instr; 478 return (0); 479 } 480 481 FTSENT * 482 fts_children(sp, instr) 483 FTS *sp; 484 int instr; 485 { 486 FTSENT *p; 487 int fd; 488 489 if (instr != 0 && instr != FTS_NAMEONLY) { 490 errno = EINVAL; 491 return (NULL); 492 } 493 494 /* Set current node pointer. */ 495 p = sp->fts_cur; 496 497 /* 498 * Errno set to 0 so user can distinguish empty directory from 499 * an error. 500 */ 501 errno = 0; 502 503 /* Fatal errors stop here. */ 504 if (ISSET(FTS_STOP)) 505 return (NULL); 506 507 /* Return logical hierarchy of user's arguments. */ 508 if (p->fts_info == FTS_INIT) 509 return (p->fts_link); 510 511 /* 512 * If not a directory being visited in pre-order, stop here. Could 513 * allow FTS_DNR, assuming the user has fixed the problem, but the 514 * same effect is available with FTS_AGAIN. 515 */ 516 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 517 return (NULL); 518 519 /* Free up any previous child list. */ 520 if (sp->fts_child != NULL) 521 fts_lfree(sp->fts_child); 522 523 if (instr == FTS_NAMEONLY) { 524 SET(FTS_NAMEONLY); 525 instr = BNAMES; 526 } else 527 instr = BCHILD; 528 529 /* 530 * If using chdir on a relative path and called BEFORE fts_read does 531 * its chdir to the root of a traversal, we can lose -- we need to 532 * chdir into the subdirectory, and we don't know where the current 533 * directory is, so we can't get back so that the upcoming chdir by 534 * fts_read will work. 535 */ 536 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 537 ISSET(FTS_NOCHDIR)) 538 return (sp->fts_child = fts_build(sp, instr)); 539 540 if ((fd = _open(".", O_RDONLY, 0)) < 0) 541 return (NULL); 542 sp->fts_child = fts_build(sp, instr); 543 if (fchdir(fd)) 544 return (NULL); 545 (void)_close(fd); 546 return (sp->fts_child); 547 } 548 549 #ifndef fts_get_clientptr 550 #error "fts_get_clientptr not defined" 551 #endif 552 553 void * 554 (fts_get_clientptr)(FTS *sp) 555 { 556 557 return (fts_get_clientptr(sp)); 558 } 559 560 #ifndef fts_get_stream 561 #error "fts_get_stream not defined" 562 #endif 563 564 FTS * 565 (fts_get_stream)(FTSENT *p) 566 { 567 return (fts_get_stream(p)); 568 } 569 570 void 571 fts_set_clientptr(FTS *sp, void *clientptr) 572 { 573 574 sp->fts_clientptr = clientptr; 575 } 576 577 /* 578 * This is the tricky part -- do not casually change *anything* in here. The 579 * idea is to build the linked list of entries that are used by fts_children 580 * and fts_read. There are lots of special cases. 581 * 582 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 583 * set and it's a physical walk (so that symbolic links can't be directories), 584 * we can do things quickly. First, if it's a 4.4BSD file system, the type 585 * of the file is in the directory entry. Otherwise, we assume that the number 586 * of subdirectories in a node is equal to the number of links to the parent. 587 * The former skips all stat calls. The latter skips stat calls in any leaf 588 * directories and for any files after the subdirectories in the directory have 589 * been found, cutting the stat calls by about 2/3. 590 */ 591 static FTSENT * 592 fts_build(sp, type) 593 FTS *sp; 594 int type; 595 { 596 struct dirent *dp; 597 FTSENT *p, *head; 598 int nitems; 599 FTSENT *cur, *tail; 600 DIR *dirp; 601 void *oldaddr; 602 int cderrno, descend, len, level, maxlen, nlinks, oflag, saved_errno, 603 nostat, doadjust; 604 char *cp; 605 606 /* Set current node pointer. */ 607 cur = sp->fts_cur; 608 609 /* 610 * Open the directory for reading. If this fails, we're done. 611 * If being called from fts_read, set the fts_info field. 612 */ 613 #ifdef FTS_WHITEOUT 614 if (ISSET(FTS_WHITEOUT)) 615 oflag = DTF_NODUP|DTF_REWIND; 616 else 617 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND; 618 #else 619 #define __opendir2(path, flag) opendir(path) 620 #endif 621 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 622 if (type == BREAD) { 623 cur->fts_info = FTS_DNR; 624 cur->fts_errno = errno; 625 } 626 return (NULL); 627 } 628 629 /* 630 * Nlinks is the number of possible entries of type directory in the 631 * directory if we're cheating on stat calls, 0 if we're not doing 632 * any stat calls at all, -1 if we're doing stats on everything. 633 */ 634 if (type == BNAMES) { 635 nlinks = 0; 636 /* Be quiet about nostat, GCC. */ 637 nostat = 0; 638 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) { 639 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 640 nostat = 1; 641 } else { 642 nlinks = -1; 643 nostat = 0; 644 } 645 646 #ifdef notdef 647 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 648 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 649 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 650 #endif 651 /* 652 * If we're going to need to stat anything or we want to descend 653 * and stay in the directory, chdir. If this fails we keep going, 654 * but set a flag so we don't chdir after the post-order visit. 655 * We won't be able to stat anything, but we can still return the 656 * names themselves. Note, that since fts_read won't be able to 657 * chdir into the directory, it will have to return different path 658 * names than before, i.e. "a/b" instead of "b". Since the node 659 * has already been visited in pre-order, have to wait until the 660 * post-order visit to return the error. There is a special case 661 * here, if there was nothing to stat then it's not an error to 662 * not be able to stat. This is all fairly nasty. If a program 663 * needed sorted entries or stat information, they had better be 664 * checking FTS_NS on the returned nodes. 665 */ 666 cderrno = 0; 667 if (nlinks || type == BREAD) { 668 if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) { 669 if (nlinks && type == BREAD) 670 cur->fts_errno = errno; 671 cur->fts_flags |= FTS_DONTCHDIR; 672 descend = 0; 673 cderrno = errno; 674 (void)closedir(dirp); 675 dirp = NULL; 676 } else 677 descend = 1; 678 } else 679 descend = 0; 680 681 /* 682 * Figure out the max file name length that can be stored in the 683 * current path -- the inner loop allocates more path as necessary. 684 * We really wouldn't have to do the maxlen calculations here, we 685 * could do them in fts_read before returning the path, but it's a 686 * lot easier here since the length is part of the dirent structure. 687 * 688 * If not changing directories set a pointer so that can just append 689 * each new name into the path. 690 */ 691 len = NAPPEND(cur); 692 if (ISSET(FTS_NOCHDIR)) { 693 cp = sp->fts_path + len; 694 *cp++ = '/'; 695 } else { 696 /* GCC, you're too verbose. */ 697 cp = NULL; 698 } 699 len++; 700 maxlen = sp->fts_pathlen - len; 701 702 level = cur->fts_level + 1; 703 704 /* Read the directory, attaching each entry to the `link' pointer. */ 705 doadjust = 0; 706 for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) { 707 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 708 continue; 709 710 if ((p = fts_alloc(sp, dp->d_name, (int)dp->d_namlen)) == NULL) 711 goto mem1; 712 if (dp->d_namlen >= maxlen) { /* include space for NUL */ 713 oldaddr = sp->fts_path; 714 if (fts_palloc(sp, dp->d_namlen + len + 1)) { 715 /* 716 * No more memory for path or structures. Save 717 * errno, free up the current structure and the 718 * structures already allocated. 719 */ 720 mem1: saved_errno = errno; 721 if (p) 722 free(p); 723 fts_lfree(head); 724 (void)closedir(dirp); 725 cur->fts_info = FTS_ERR; 726 SET(FTS_STOP); 727 errno = saved_errno; 728 return (NULL); 729 } 730 /* Did realloc() change the pointer? */ 731 if (oldaddr != sp->fts_path) { 732 doadjust = 1; 733 if (ISSET(FTS_NOCHDIR)) 734 cp = sp->fts_path + len; 735 } 736 maxlen = sp->fts_pathlen - len; 737 } 738 739 if (len + dp->d_namlen >= USHRT_MAX) { 740 /* 741 * In an FTSENT, fts_pathlen is a u_short so it is 742 * possible to wraparound here. If we do, free up 743 * the current structure and the structures already 744 * allocated, then error out with ENAMETOOLONG. 745 */ 746 free(p); 747 fts_lfree(head); 748 (void)closedir(dirp); 749 cur->fts_info = FTS_ERR; 750 SET(FTS_STOP); 751 errno = ENAMETOOLONG; 752 return (NULL); 753 } 754 p->fts_level = level; 755 p->fts_parent = sp->fts_cur; 756 p->fts_pathlen = len + dp->d_namlen; 757 758 #ifdef FTS_WHITEOUT 759 if (dp->d_type == DT_WHT) 760 p->fts_flags |= FTS_ISW; 761 #endif 762 763 if (cderrno) { 764 if (nlinks) { 765 p->fts_info = FTS_NS; 766 p->fts_errno = cderrno; 767 } else 768 p->fts_info = FTS_NSOK; 769 p->fts_accpath = cur->fts_accpath; 770 } else if (nlinks == 0 771 #ifdef DT_DIR 772 || (nostat && 773 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN) 774 #endif 775 ) { 776 p->fts_accpath = 777 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 778 p->fts_info = FTS_NSOK; 779 } else { 780 /* Build a file name for fts_stat to stat. */ 781 if (ISSET(FTS_NOCHDIR)) { 782 p->fts_accpath = p->fts_path; 783 memmove(cp, p->fts_name, p->fts_namelen + 1); 784 } else 785 p->fts_accpath = p->fts_name; 786 /* Stat it. */ 787 p->fts_info = fts_stat(sp, p, 0); 788 789 /* Decrement link count if applicable. */ 790 if (nlinks > 0 && (p->fts_info == FTS_D || 791 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 792 --nlinks; 793 } 794 795 /* We walk in directory order so "ls -f" doesn't get upset. */ 796 p->fts_link = NULL; 797 if (head == NULL) 798 head = tail = p; 799 else { 800 tail->fts_link = p; 801 tail = p; 802 } 803 ++nitems; 804 } 805 if (dirp) 806 (void)closedir(dirp); 807 808 /* 809 * If realloc() changed the address of the path, adjust the 810 * addresses for the rest of the tree and the dir list. 811 */ 812 if (doadjust) 813 fts_padjust(sp, head); 814 815 /* 816 * If not changing directories, reset the path back to original 817 * state. 818 */ 819 if (ISSET(FTS_NOCHDIR)) { 820 if (len == sp->fts_pathlen || nitems == 0) 821 --cp; 822 *cp = '\0'; 823 } 824 825 /* 826 * If descended after called from fts_children or after called from 827 * fts_read and nothing found, get back. At the root level we use 828 * the saved fd; if one of fts_open()'s arguments is a relative path 829 * to an empty directory, we wind up here with no other way back. If 830 * can't get back, we're done. 831 */ 832 if (descend && (type == BCHILD || !nitems) && 833 (cur->fts_level == FTS_ROOTLEVEL ? 834 FCHDIR(sp, sp->fts_rfd) : 835 fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) { 836 cur->fts_info = FTS_ERR; 837 SET(FTS_STOP); 838 return (NULL); 839 } 840 841 /* If didn't find anything, return NULL. */ 842 if (!nitems) { 843 if (type == BREAD) 844 cur->fts_info = FTS_DP; 845 return (NULL); 846 } 847 848 /* Sort the entries. */ 849 if (sp->fts_compar && nitems > 1) 850 head = fts_sort(sp, head, nitems); 851 return (head); 852 } 853 854 static u_short 855 fts_stat(sp, p, follow) 856 FTS *sp; 857 FTSENT *p; 858 int follow; 859 { 860 FTSENT *t; 861 dev_t dev; 862 ino_t ino; 863 struct stat *sbp, sb; 864 int saved_errno; 865 866 /* If user needs stat info, stat buffer already allocated. */ 867 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 868 869 #ifdef FTS_WHITEOUT 870 /* check for whiteout */ 871 if (p->fts_flags & FTS_ISW) { 872 if (sbp != &sb) { 873 memset(sbp, '\0', sizeof (*sbp)); 874 sbp->st_mode = S_IFWHT; 875 } 876 return (FTS_W); 877 } 878 #endif 879 880 /* 881 * If doing a logical walk, or application requested FTS_FOLLOW, do 882 * a stat(2). If that fails, check for a non-existent symlink. If 883 * fail, set the errno from the stat call. 884 */ 885 if (ISSET(FTS_LOGICAL) || follow) { 886 if (stat(p->fts_accpath, sbp)) { 887 saved_errno = errno; 888 if (!lstat(p->fts_accpath, sbp)) { 889 errno = 0; 890 return (FTS_SLNONE); 891 } 892 p->fts_errno = saved_errno; 893 goto err; 894 } 895 } else if (lstat(p->fts_accpath, sbp)) { 896 p->fts_errno = errno; 897 err: memset(sbp, 0, sizeof(struct stat)); 898 return (FTS_NS); 899 } 900 901 if (S_ISDIR(sbp->st_mode)) { 902 /* 903 * Set the device/inode. Used to find cycles and check for 904 * crossing mount points. Also remember the link count, used 905 * in fts_build to limit the number of stat calls. It is 906 * understood that these fields are only referenced if fts_info 907 * is set to FTS_D. 908 */ 909 dev = p->fts_dev = sbp->st_dev; 910 ino = p->fts_ino = sbp->st_ino; 911 p->fts_nlink = sbp->st_nlink; 912 913 if (ISDOT(p->fts_name)) 914 return (FTS_DOT); 915 916 /* 917 * Cycle detection is done by brute force when the directory 918 * is first encountered. If the tree gets deep enough or the 919 * number of symbolic links to directories is high enough, 920 * something faster might be worthwhile. 921 */ 922 for (t = p->fts_parent; 923 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 924 if (ino == t->fts_ino && dev == t->fts_dev) { 925 p->fts_cycle = t; 926 return (FTS_DC); 927 } 928 return (FTS_D); 929 } 930 if (S_ISLNK(sbp->st_mode)) 931 return (FTS_SL); 932 if (S_ISREG(sbp->st_mode)) 933 return (FTS_F); 934 return (FTS_DEFAULT); 935 } 936 937 /* 938 * The comparison function takes pointers to pointers to FTSENT structures. 939 * Qsort wants a comparison function that takes pointers to void. 940 * (Both with appropriate levels of const-poisoning, of course!) 941 * Use a trampoline function to deal with the difference. 942 */ 943 static int 944 fts_compar(const void *a, const void *b) 945 { 946 FTS *parent; 947 948 parent = (*(const FTSENT * const *)a)->fts_fts; 949 return (*parent->fts_compar)(a, b); 950 } 951 952 static FTSENT * 953 fts_sort(sp, head, nitems) 954 FTS *sp; 955 FTSENT *head; 956 int nitems; 957 { 958 FTSENT **ap, *p; 959 960 /* 961 * Construct an array of pointers to the structures and call qsort(3). 962 * Reassemble the array in the order returned by qsort. If unable to 963 * sort for memory reasons, return the directory entries in their 964 * current order. Allocate enough space for the current needs plus 965 * 40 so don't realloc one entry at a time. 966 */ 967 if (nitems > sp->fts_nitems) { 968 sp->fts_nitems = nitems + 40; 969 if ((sp->fts_array = reallocf(sp->fts_array, 970 sp->fts_nitems * sizeof(FTSENT *))) == NULL) { 971 sp->fts_nitems = 0; 972 return (head); 973 } 974 } 975 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 976 *ap++ = p; 977 qsort(sp->fts_array, nitems, sizeof(FTSENT *), fts_compar); 978 for (head = *(ap = sp->fts_array); --nitems; ++ap) 979 ap[0]->fts_link = ap[1]; 980 ap[0]->fts_link = NULL; 981 return (head); 982 } 983 984 static FTSENT * 985 fts_alloc(sp, name, namelen) 986 FTS *sp; 987 char *name; 988 int namelen; 989 { 990 FTSENT *p; 991 size_t len; 992 993 struct ftsent_withstat { 994 FTSENT ent; 995 struct stat statbuf; 996 }; 997 998 /* 999 * The file name is a variable length array and no stat structure is 1000 * necessary if the user has set the nostat bit. Allocate the FTSENT 1001 * structure, the file name and the stat structure in one chunk, but 1002 * be careful that the stat structure is reasonably aligned. 1003 */ 1004 if (ISSET(FTS_NOSTAT)) 1005 len = sizeof(FTSENT) + namelen + 1; 1006 else 1007 len = sizeof(struct ftsent_withstat) + namelen + 1; 1008 1009 if ((p = malloc(len)) == NULL) 1010 return (NULL); 1011 1012 if (ISSET(FTS_NOSTAT)) { 1013 p->fts_name = (char *)(p + 1); 1014 p->fts_statp = NULL; 1015 } else { 1016 p->fts_name = (char *)((struct ftsent_withstat *)p + 1); 1017 p->fts_statp = &((struct ftsent_withstat *)p)->statbuf; 1018 } 1019 1020 /* Copy the name and guarantee NUL termination. */ 1021 memcpy(p->fts_name, name, namelen); 1022 p->fts_name[namelen] = '\0'; 1023 p->fts_namelen = namelen; 1024 p->fts_path = sp->fts_path; 1025 p->fts_errno = 0; 1026 p->fts_flags = 0; 1027 p->fts_instr = FTS_NOINSTR; 1028 p->fts_number = 0; 1029 p->fts_pointer = NULL; 1030 p->fts_fts = sp; 1031 return (p); 1032 } 1033 1034 static void 1035 fts_lfree(head) 1036 FTSENT *head; 1037 { 1038 FTSENT *p; 1039 1040 /* Free a linked list of structures. */ 1041 while ((p = head)) { 1042 head = head->fts_link; 1043 free(p); 1044 } 1045 } 1046 1047 /* 1048 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 1049 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 1050 * though the kernel won't resolve them. Add the size (not just what's needed) 1051 * plus 256 bytes so don't realloc the path 2 bytes at a time. 1052 */ 1053 static int 1054 fts_palloc(sp, more) 1055 FTS *sp; 1056 size_t more; 1057 { 1058 1059 sp->fts_pathlen += more + 256; 1060 /* 1061 * Check for possible wraparound. In an FTS, fts_pathlen is 1062 * a signed int but in an FTSENT it is an unsigned short. 1063 * We limit fts_pathlen to USHRT_MAX to be safe in both cases. 1064 */ 1065 if (sp->fts_pathlen < 0 || sp->fts_pathlen >= USHRT_MAX) { 1066 if (sp->fts_path) 1067 free(sp->fts_path); 1068 sp->fts_path = NULL; 1069 errno = ENAMETOOLONG; 1070 return (1); 1071 } 1072 sp->fts_path = reallocf(sp->fts_path, sp->fts_pathlen); 1073 return (sp->fts_path == NULL); 1074 } 1075 1076 /* 1077 * When the path is realloc'd, have to fix all of the pointers in structures 1078 * already returned. 1079 */ 1080 static void 1081 fts_padjust(sp, head) 1082 FTS *sp; 1083 FTSENT *head; 1084 { 1085 FTSENT *p; 1086 char *addr = sp->fts_path; 1087 1088 #define ADJUST(p) do { \ 1089 if ((p)->fts_accpath != (p)->fts_name) { \ 1090 (p)->fts_accpath = \ 1091 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \ 1092 } \ 1093 (p)->fts_path = addr; \ 1094 } while (0) 1095 /* Adjust the current set of children. */ 1096 for (p = sp->fts_child; p; p = p->fts_link) 1097 ADJUST(p); 1098 1099 /* Adjust the rest of the tree, including the current level. */ 1100 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) { 1101 ADJUST(p); 1102 p = p->fts_link ? p->fts_link : p->fts_parent; 1103 } 1104 } 1105 1106 static size_t 1107 fts_maxarglen(argv) 1108 char * const *argv; 1109 { 1110 size_t len, max; 1111 1112 for (max = 0; *argv; ++argv) 1113 if ((len = strlen(*argv)) > max) 1114 max = len; 1115 return (max + 1); 1116 } 1117 1118 /* 1119 * Change to dir specified by fd or p->fts_accpath without getting 1120 * tricked by someone changing the world out from underneath us. 1121 * Assumes p->fts_dev and p->fts_ino are filled in. 1122 */ 1123 static int 1124 fts_safe_changedir(sp, p, fd, path) 1125 FTS *sp; 1126 FTSENT *p; 1127 int fd; 1128 char *path; 1129 { 1130 int ret, oerrno, newfd; 1131 struct stat sb; 1132 1133 newfd = fd; 1134 if (ISSET(FTS_NOCHDIR)) 1135 return (0); 1136 if (fd < 0 && (newfd = _open(path, O_RDONLY, 0)) < 0) 1137 return (-1); 1138 if (_fstat(newfd, &sb)) { 1139 ret = -1; 1140 goto bail; 1141 } 1142 if (p->fts_dev != sb.st_dev || p->fts_ino != sb.st_ino) { 1143 errno = ENOENT; /* disinformation */ 1144 ret = -1; 1145 goto bail; 1146 } 1147 ret = fchdir(newfd); 1148 bail: 1149 oerrno = errno; 1150 if (fd < 0) 1151 (void)_close(newfd); 1152 errno = oerrno; 1153 return (ret); 1154 } 1155