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 * 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 * $OpenBSD: fts.c,v 1.22 1999/10/03 19:22:22 millert Exp $ 30 */ 31 32 #if 0 33 #if defined(LIBC_SCCS) && !defined(lint) 34 static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94"; 35 #endif /* LIBC_SCCS and not lint */ 36 #endif 37 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include "namespace.h" 42 #include <sys/param.h> 43 #include <sys/mount.h> 44 #include <sys/stat.h> 45 46 #include <dirent.h> 47 #include <errno.h> 48 #include <fcntl.h> 49 #include <stdlib.h> 50 #include <string.h> 51 #include <unistd.h> 52 #include "fts-compat.h" 53 #include "un-namespace.h" 54 55 #include "gen-private.h" 56 57 FTSENT *__fts_children_44bsd(FTS *, int); 58 int __fts_close_44bsd(FTS *); 59 void *__fts_get_clientptr_44bsd(FTS *); 60 FTS *__fts_get_stream_44bsd(FTSENT *); 61 FTS *__fts_open_44bsd(char * const *, int, 62 int (*)(const FTSENT * const *, const FTSENT * const *)); 63 FTSENT *__fts_read_44bsd(FTS *); 64 int __fts_set_44bsd(FTS *, FTSENT *, int); 65 void __fts_set_clientptr_44bsd(FTS *, void *); 66 67 static FTSENT *fts_alloc(FTS *, char *, int); 68 static FTSENT *fts_build(FTS *, int); 69 static void fts_lfree(FTSENT *); 70 static void fts_load(FTS *, FTSENT *); 71 static size_t fts_maxarglen(char * const *); 72 static void fts_padjust(FTS *, FTSENT *); 73 static int fts_palloc(FTS *, size_t); 74 static FTSENT *fts_sort(FTS *, FTSENT *, int); 75 static u_short fts_stat(FTS *, FTSENT *, int); 76 static int fts_safe_changedir(FTS *, FTSENT *, int, char *); 77 static int fts_ufslinks(FTS *, const FTSENT *); 78 79 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2]))) 80 81 #define CLR(opt) (sp->fts_options &= ~(opt)) 82 #define ISSET(opt) (sp->fts_options & (opt)) 83 #define SET(opt) (sp->fts_options |= (opt)) 84 85 #define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) && fchdir(fd)) 86 87 /* fts_build flags */ 88 #define BCHILD 1 /* fts_children */ 89 #define BNAMES 2 /* fts_children, names only */ 90 #define BREAD 3 /* fts_read */ 91 92 /* 93 * Internal representation of an FTS, including extra implementation 94 * details. The FTS returned from fts_open points to this structure's 95 * ftsp_fts member (and can be cast to an _fts_private as required) 96 */ 97 struct _fts_private { 98 FTS ftsp_fts; 99 struct statfs ftsp_statfs; 100 dev_t ftsp_dev; 101 int ftsp_linksreliable; 102 }; 103 104 /* 105 * The "FTS_NOSTAT" option can avoid a lot of calls to stat(2) if it 106 * knows that a directory could not possibly have subdirectories. This 107 * is decided by looking at the link count: a subdirectory would 108 * increment its parent's link count by virtue of its own ".." entry. 109 * This assumption only holds for UFS-like filesystems that implement 110 * links and directories this way, so we must punt for others. 111 */ 112 113 static const char *ufslike_filesystems[] = { 114 "ufs", 115 "zfs", 116 "nfs", 117 "nfs4", 118 "ext2fs", 119 0 120 }; 121 122 FTS * 123 __fts_open_44bsd(char * const *argv, int options, 124 int (*compar)(const FTSENT * const *, const FTSENT * const *)) 125 { 126 struct _fts_private *priv; 127 FTS *sp; 128 FTSENT *p, *root; 129 int nitems; 130 FTSENT *parent, *tmp; 131 int len; 132 133 /* Options check. */ 134 if (options & ~FTS_OPTIONMASK) { 135 errno = EINVAL; 136 return (NULL); 137 } 138 139 /* Allocate/initialize the stream. */ 140 if ((priv = calloc(1, sizeof(*priv))) == NULL) 141 return (NULL); 142 sp = &priv->ftsp_fts; 143 sp->fts_compar = compar; 144 sp->fts_options = options; 145 146 /* Shush, GCC. */ 147 tmp = NULL; 148 149 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 150 if (ISSET(FTS_LOGICAL)) 151 SET(FTS_NOCHDIR); 152 153 /* 154 * Start out with 1K of path space, and enough, in any case, 155 * to hold the user's paths. 156 */ 157 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN))) 158 goto mem1; 159 160 /* Allocate/initialize root's parent. */ 161 if ((parent = fts_alloc(sp, "", 0)) == NULL) 162 goto mem2; 163 parent->fts_level = FTS_ROOTPARENTLEVEL; 164 165 /* Allocate/initialize root(s). */ 166 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) { 167 /* Don't allow zero-length paths. */ 168 if ((len = strlen(*argv)) == 0) { 169 errno = ENOENT; 170 goto mem3; 171 } 172 173 p = fts_alloc(sp, *argv, len); 174 p->fts_level = FTS_ROOTLEVEL; 175 p->fts_parent = parent; 176 p->fts_accpath = p->fts_name; 177 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 178 179 /* Command-line "." and ".." are real directories. */ 180 if (p->fts_info == FTS_DOT) 181 p->fts_info = FTS_D; 182 183 /* 184 * If comparison routine supplied, traverse in sorted 185 * order; otherwise traverse in the order specified. 186 */ 187 if (compar) { 188 p->fts_link = root; 189 root = p; 190 } else { 191 p->fts_link = NULL; 192 if (root == NULL) 193 tmp = root = p; 194 else { 195 tmp->fts_link = p; 196 tmp = p; 197 } 198 } 199 } 200 if (compar && nitems > 1) 201 root = fts_sort(sp, root, nitems); 202 203 /* 204 * Allocate a dummy pointer and make fts_read think that we've just 205 * finished the node before the root(s); set p->fts_info to FTS_INIT 206 * so that everything about the "current" node is ignored. 207 */ 208 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 209 goto mem3; 210 sp->fts_cur->fts_link = root; 211 sp->fts_cur->fts_info = FTS_INIT; 212 213 /* 214 * If using chdir(2), grab a file descriptor pointing to dot to ensure 215 * that we can get back here; this could be avoided for some paths, 216 * but almost certainly not worth the effort. Slashes, symbolic links, 217 * and ".." are all fairly nasty problems. Note, if we can't get the 218 * descriptor we run anyway, just more slowly. 219 */ 220 if (!ISSET(FTS_NOCHDIR) && 221 (sp->fts_rfd = _open(".", O_RDONLY | O_CLOEXEC, 0)) < 0) 222 SET(FTS_NOCHDIR); 223 224 return (sp); 225 226 mem3: fts_lfree(root); 227 free(parent); 228 mem2: free(sp->fts_path); 229 mem1: free(sp); 230 return (NULL); 231 } 232 233 static void 234 fts_load(FTS *sp, FTSENT *p) 235 { 236 int len; 237 char *cp; 238 239 /* 240 * Load the stream structure for the next traversal. Since we don't 241 * actually enter the directory until after the preorder visit, set 242 * the fts_accpath field specially so the chdir gets done to the right 243 * place and the user can access the first node. From fts_open it's 244 * known that the path will fit. 245 */ 246 len = p->fts_pathlen = p->fts_namelen; 247 memmove(sp->fts_path, p->fts_name, len + 1); 248 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 249 len = strlen(++cp); 250 memmove(p->fts_name, cp, len + 1); 251 p->fts_namelen = len; 252 } 253 p->fts_accpath = p->fts_path = sp->fts_path; 254 sp->fts_dev = p->fts_dev; 255 } 256 257 int 258 __fts_close_44bsd(FTS *sp) 259 { 260 FTSENT *freep, *p; 261 int saved_errno; 262 263 /* 264 * This still works if we haven't read anything -- the dummy structure 265 * points to the root list, so we step through to the end of the root 266 * list which has a valid parent pointer. 267 */ 268 if (sp->fts_cur) { 269 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 270 freep = p; 271 p = p->fts_link != NULL ? p->fts_link : p->fts_parent; 272 free(freep); 273 } 274 free(p); 275 } 276 277 /* Free up child linked list, sort array, path buffer. */ 278 if (sp->fts_child) 279 fts_lfree(sp->fts_child); 280 if (sp->fts_array) 281 free(sp->fts_array); 282 free(sp->fts_path); 283 284 /* Return to original directory, save errno if necessary. */ 285 if (!ISSET(FTS_NOCHDIR)) { 286 saved_errno = fchdir(sp->fts_rfd) ? errno : 0; 287 (void)_close(sp->fts_rfd); 288 289 /* Set errno and return. */ 290 if (saved_errno != 0) { 291 /* Free up the stream pointer. */ 292 free(sp); 293 errno = saved_errno; 294 return (-1); 295 } 296 } 297 298 /* Free up the stream pointer. */ 299 free(sp); 300 return (0); 301 } 302 303 /* 304 * Special case of "/" at the end of the path so that slashes aren't 305 * appended which would cause paths to be written as "....//foo". 306 */ 307 #define NAPPEND(p) \ 308 (p->fts_path[p->fts_pathlen - 1] == '/' \ 309 ? p->fts_pathlen - 1 : p->fts_pathlen) 310 311 FTSENT * 312 __fts_read_44bsd(FTS *sp) 313 { 314 FTSENT *p, *tmp; 315 int instr; 316 char *t; 317 int saved_errno; 318 319 /* If finished or unrecoverable error, return NULL. */ 320 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 321 return (NULL); 322 323 /* Set current node pointer. */ 324 p = sp->fts_cur; 325 326 /* Save and zero out user instructions. */ 327 instr = p->fts_instr; 328 p->fts_instr = FTS_NOINSTR; 329 330 /* Any type of file may be re-visited; re-stat and re-turn. */ 331 if (instr == FTS_AGAIN) { 332 p->fts_info = fts_stat(sp, p, 0); 333 return (p); 334 } 335 336 /* 337 * Following a symlink -- SLNONE test allows application to see 338 * SLNONE and recover. If indirecting through a symlink, have 339 * keep a pointer to current location. If unable to get that 340 * pointer, follow fails. 341 */ 342 if (instr == FTS_FOLLOW && 343 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 344 p->fts_info = fts_stat(sp, p, 1); 345 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 346 if ((p->fts_symfd = _open(".", O_RDONLY | O_CLOEXEC, 347 0)) < 0) { 348 p->fts_errno = errno; 349 p->fts_info = FTS_ERR; 350 } else 351 p->fts_flags |= FTS_SYMFOLLOW; 352 } 353 return (p); 354 } 355 356 /* Directory in pre-order. */ 357 if (p->fts_info == FTS_D) { 358 /* If skipped or crossed mount point, do post-order visit. */ 359 if (instr == FTS_SKIP || 360 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) { 361 if (p->fts_flags & FTS_SYMFOLLOW) 362 (void)_close(p->fts_symfd); 363 if (sp->fts_child) { 364 fts_lfree(sp->fts_child); 365 sp->fts_child = NULL; 366 } 367 p->fts_info = FTS_DP; 368 return (p); 369 } 370 371 /* Rebuild if only read the names and now traversing. */ 372 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) { 373 CLR(FTS_NAMEONLY); 374 fts_lfree(sp->fts_child); 375 sp->fts_child = NULL; 376 } 377 378 /* 379 * Cd to the subdirectory. 380 * 381 * If have already read and now fail to chdir, whack the list 382 * to make the names come out right, and set the parent errno 383 * so the application will eventually get an error condition. 384 * Set the FTS_DONTCHDIR flag so that when we logically change 385 * directories back to the parent we don't do a chdir. 386 * 387 * If haven't read do so. If the read fails, fts_build sets 388 * FTS_STOP or the fts_info field of the node. 389 */ 390 if (sp->fts_child != NULL) { 391 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) { 392 p->fts_errno = errno; 393 p->fts_flags |= FTS_DONTCHDIR; 394 for (p = sp->fts_child; p != NULL; 395 p = p->fts_link) 396 p->fts_accpath = 397 p->fts_parent->fts_accpath; 398 } 399 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 400 if (ISSET(FTS_STOP)) 401 return (NULL); 402 return (p); 403 } 404 p = sp->fts_child; 405 sp->fts_child = NULL; 406 goto name; 407 } 408 409 /* Move to the next node on this level. */ 410 next: tmp = p; 411 if ((p = p->fts_link) != NULL) { 412 free(tmp); 413 414 /* 415 * If reached the top, return to the original directory (or 416 * the root of the tree), and load the paths for the next root. 417 */ 418 if (p->fts_level == FTS_ROOTLEVEL) { 419 if (FCHDIR(sp, sp->fts_rfd)) { 420 SET(FTS_STOP); 421 return (NULL); 422 } 423 fts_load(sp, p); 424 return (sp->fts_cur = p); 425 } 426 427 /* 428 * User may have called fts_set on the node. If skipped, 429 * ignore. If followed, get a file descriptor so we can 430 * get back if necessary. 431 */ 432 if (p->fts_instr == FTS_SKIP) 433 goto next; 434 if (p->fts_instr == FTS_FOLLOW) { 435 p->fts_info = fts_stat(sp, p, 1); 436 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 437 if ((p->fts_symfd = 438 _open(".", O_RDONLY | O_CLOEXEC, 0)) < 0) { 439 p->fts_errno = errno; 440 p->fts_info = FTS_ERR; 441 } else 442 p->fts_flags |= FTS_SYMFOLLOW; 443 } 444 p->fts_instr = FTS_NOINSTR; 445 } 446 447 name: t = sp->fts_path + NAPPEND(p->fts_parent); 448 *t++ = '/'; 449 memmove(t, p->fts_name, p->fts_namelen + 1); 450 return (sp->fts_cur = p); 451 } 452 453 /* Move up to the parent node. */ 454 p = tmp->fts_parent; 455 free(tmp); 456 457 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 458 /* 459 * Done; free everything up and set errno to 0 so the user 460 * can distinguish between error and EOF. 461 */ 462 free(p); 463 errno = 0; 464 return (sp->fts_cur = NULL); 465 } 466 467 /* NUL terminate the pathname. */ 468 sp->fts_path[p->fts_pathlen] = '\0'; 469 470 /* 471 * Return to the parent directory. If at a root node or came through 472 * a symlink, go back through the file descriptor. Otherwise, cd up 473 * one directory. 474 */ 475 if (p->fts_level == FTS_ROOTLEVEL) { 476 if (FCHDIR(sp, sp->fts_rfd)) { 477 SET(FTS_STOP); 478 return (NULL); 479 } 480 } else if (p->fts_flags & FTS_SYMFOLLOW) { 481 if (FCHDIR(sp, p->fts_symfd)) { 482 saved_errno = errno; 483 (void)_close(p->fts_symfd); 484 errno = saved_errno; 485 SET(FTS_STOP); 486 return (NULL); 487 } 488 (void)_close(p->fts_symfd); 489 } else if (!(p->fts_flags & FTS_DONTCHDIR) && 490 fts_safe_changedir(sp, p->fts_parent, -1, "..")) { 491 SET(FTS_STOP); 492 return (NULL); 493 } 494 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 495 return (sp->fts_cur = p); 496 } 497 498 /* 499 * Fts_set takes the stream as an argument although it's not used in this 500 * implementation; it would be necessary if anyone wanted to add global 501 * semantics to fts using fts_set. An error return is allowed for similar 502 * reasons. 503 */ 504 /* ARGSUSED */ 505 int 506 __fts_set_44bsd(FTS *sp, FTSENT *p, int instr) 507 { 508 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW && 509 instr != FTS_NOINSTR && instr != FTS_SKIP) { 510 errno = EINVAL; 511 return (1); 512 } 513 p->fts_instr = instr; 514 return (0); 515 } 516 517 FTSENT * 518 __fts_children_44bsd(FTS *sp, int instr) 519 { 520 FTSENT *p; 521 int fd; 522 523 if (instr != 0 && instr != FTS_NAMEONLY) { 524 errno = EINVAL; 525 return (NULL); 526 } 527 528 /* Set current node pointer. */ 529 p = sp->fts_cur; 530 531 /* 532 * Errno set to 0 so user can distinguish empty directory from 533 * an error. 534 */ 535 errno = 0; 536 537 /* Fatal errors stop here. */ 538 if (ISSET(FTS_STOP)) 539 return (NULL); 540 541 /* Return logical hierarchy of user's arguments. */ 542 if (p->fts_info == FTS_INIT) 543 return (p->fts_link); 544 545 /* 546 * If not a directory being visited in pre-order, stop here. Could 547 * allow FTS_DNR, assuming the user has fixed the problem, but the 548 * same effect is available with FTS_AGAIN. 549 */ 550 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 551 return (NULL); 552 553 /* Free up any previous child list. */ 554 if (sp->fts_child != NULL) 555 fts_lfree(sp->fts_child); 556 557 if (instr == FTS_NAMEONLY) { 558 SET(FTS_NAMEONLY); 559 instr = BNAMES; 560 } else 561 instr = BCHILD; 562 563 /* 564 * If using chdir on a relative path and called BEFORE fts_read does 565 * its chdir to the root of a traversal, we can lose -- we need to 566 * chdir into the subdirectory, and we don't know where the current 567 * directory is, so we can't get back so that the upcoming chdir by 568 * fts_read will work. 569 */ 570 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 571 ISSET(FTS_NOCHDIR)) 572 return (sp->fts_child = fts_build(sp, instr)); 573 574 if ((fd = _open(".", O_RDONLY | O_CLOEXEC, 0)) < 0) 575 return (NULL); 576 sp->fts_child = fts_build(sp, instr); 577 if (fchdir(fd)) 578 return (NULL); 579 (void)_close(fd); 580 return (sp->fts_child); 581 } 582 583 #ifndef fts_get_clientptr 584 #error "fts_get_clientptr not defined" 585 #endif 586 587 void * 588 (__fts_get_clientptr_44bsd)(FTS *sp) 589 { 590 591 return (fts_get_clientptr(sp)); 592 } 593 594 #ifndef fts_get_stream 595 #error "fts_get_stream not defined" 596 #endif 597 598 FTS * 599 (__fts_get_stream_44bsd)(FTSENT *p) 600 { 601 return (fts_get_stream(p)); 602 } 603 604 void 605 __fts_set_clientptr_44bsd(FTS *sp, void *clientptr) 606 { 607 608 sp->fts_clientptr = clientptr; 609 } 610 611 /* 612 * This is the tricky part -- do not casually change *anything* in here. The 613 * idea is to build the linked list of entries that are used by fts_children 614 * and fts_read. There are lots of special cases. 615 * 616 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 617 * set and it's a physical walk (so that symbolic links can't be directories), 618 * we can do things quickly. First, if it's a 4.4BSD file system, the type 619 * of the file is in the directory entry. Otherwise, we assume that the number 620 * of subdirectories in a node is equal to the number of links to the parent. 621 * The former skips all stat calls. The latter skips stat calls in any leaf 622 * directories and for any files after the subdirectories in the directory have 623 * been found, cutting the stat calls by about 2/3. 624 */ 625 static FTSENT * 626 fts_build(FTS *sp, int type) 627 { 628 struct dirent *dp; 629 FTSENT *p, *head; 630 int nitems; 631 FTSENT *cur, *tail; 632 DIR *dirp; 633 void *oldaddr; 634 size_t dnamlen; 635 int cderrno, descend, len, level, maxlen, nlinks, oflag, saved_errno, 636 nostat, doadjust; 637 char *cp; 638 639 /* Set current node pointer. */ 640 cur = sp->fts_cur; 641 642 /* 643 * Open the directory for reading. If this fails, we're done. 644 * If being called from fts_read, set the fts_info field. 645 */ 646 #ifdef FTS_WHITEOUT 647 if (ISSET(FTS_WHITEOUT)) 648 oflag = DTF_NODUP | DTF_REWIND; 649 else 650 oflag = DTF_HIDEW | DTF_NODUP | DTF_REWIND; 651 #else 652 #define __opendir2(path, flag) opendir(path) 653 #endif 654 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 655 if (type == BREAD) { 656 cur->fts_info = FTS_DNR; 657 cur->fts_errno = errno; 658 } 659 return (NULL); 660 } 661 662 /* 663 * Nlinks is the number of possible entries of type directory in the 664 * directory if we're cheating on stat calls, 0 if we're not doing 665 * any stat calls at all, -1 if we're doing stats on everything. 666 */ 667 if (type == BNAMES) { 668 nlinks = 0; 669 /* Be quiet about nostat, GCC. */ 670 nostat = 0; 671 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) { 672 if (fts_ufslinks(sp, cur)) 673 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 674 else 675 nlinks = -1; 676 nostat = 1; 677 } else { 678 nlinks = -1; 679 nostat = 0; 680 } 681 682 #ifdef notdef 683 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 684 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 685 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 686 #endif 687 /* 688 * If we're going to need to stat anything or we want to descend 689 * and stay in the directory, chdir. If this fails we keep going, 690 * but set a flag so we don't chdir after the post-order visit. 691 * We won't be able to stat anything, but we can still return the 692 * names themselves. Note, that since fts_read won't be able to 693 * chdir into the directory, it will have to return different path 694 * names than before, i.e. "a/b" instead of "b". Since the node 695 * has already been visited in pre-order, have to wait until the 696 * post-order visit to return the error. There is a special case 697 * here, if there was nothing to stat then it's not an error to 698 * not be able to stat. This is all fairly nasty. If a program 699 * needed sorted entries or stat information, they had better be 700 * checking FTS_NS on the returned nodes. 701 */ 702 cderrno = 0; 703 if (nlinks || type == BREAD) { 704 if (fts_safe_changedir(sp, cur, _dirfd(dirp), NULL)) { 705 if (nlinks && type == BREAD) 706 cur->fts_errno = errno; 707 cur->fts_flags |= FTS_DONTCHDIR; 708 descend = 0; 709 cderrno = errno; 710 } else 711 descend = 1; 712 } else 713 descend = 0; 714 715 /* 716 * Figure out the max file name length that can be stored in the 717 * current path -- the inner loop allocates more path as necessary. 718 * We really wouldn't have to do the maxlen calculations here, we 719 * could do them in fts_read before returning the path, but it's a 720 * lot easier here since the length is part of the dirent structure. 721 * 722 * If not changing directories set a pointer so that can just append 723 * each new name into the path. 724 */ 725 len = NAPPEND(cur); 726 if (ISSET(FTS_NOCHDIR)) { 727 cp = sp->fts_path + len; 728 *cp++ = '/'; 729 } else { 730 /* GCC, you're too verbose. */ 731 cp = NULL; 732 } 733 len++; 734 maxlen = sp->fts_pathlen - len; 735 736 level = cur->fts_level + 1; 737 738 /* Read the directory, attaching each entry to the `link' pointer. */ 739 doadjust = 0; 740 for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) { 741 dnamlen = dp->d_namlen; 742 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 743 continue; 744 745 if ((p = fts_alloc(sp, dp->d_name, (int)dnamlen)) == NULL) 746 goto mem1; 747 if (dnamlen >= maxlen) { /* include space for NUL */ 748 oldaddr = sp->fts_path; 749 if (fts_palloc(sp, dnamlen + len + 1)) { 750 /* 751 * No more memory for path or structures. Save 752 * errno, free up the current structure and the 753 * structures already allocated. 754 */ 755 mem1: saved_errno = errno; 756 if (p) 757 free(p); 758 fts_lfree(head); 759 (void)closedir(dirp); 760 cur->fts_info = FTS_ERR; 761 SET(FTS_STOP); 762 errno = saved_errno; 763 return (NULL); 764 } 765 /* Did realloc() change the pointer? */ 766 if (oldaddr != sp->fts_path) { 767 doadjust = 1; 768 if (ISSET(FTS_NOCHDIR)) 769 cp = sp->fts_path + len; 770 } 771 maxlen = sp->fts_pathlen - len; 772 } 773 774 if (len + dnamlen >= USHRT_MAX) { 775 /* 776 * In an FTSENT, fts_pathlen is a u_short so it is 777 * possible to wraparound here. If we do, free up 778 * the current structure and the structures already 779 * allocated, then error out with ENAMETOOLONG. 780 */ 781 free(p); 782 fts_lfree(head); 783 (void)closedir(dirp); 784 cur->fts_info = FTS_ERR; 785 SET(FTS_STOP); 786 errno = ENAMETOOLONG; 787 return (NULL); 788 } 789 p->fts_level = level; 790 p->fts_parent = sp->fts_cur; 791 p->fts_pathlen = len + dnamlen; 792 793 #ifdef FTS_WHITEOUT 794 if (dp->d_type == DT_WHT) 795 p->fts_flags |= FTS_ISW; 796 #endif 797 798 if (cderrno) { 799 if (nlinks) { 800 p->fts_info = FTS_NS; 801 p->fts_errno = cderrno; 802 } else 803 p->fts_info = FTS_NSOK; 804 p->fts_accpath = cur->fts_accpath; 805 } else if (nlinks == 0 806 #ifdef DT_DIR 807 || (nostat && 808 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN) 809 #endif 810 ) { 811 p->fts_accpath = 812 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 813 p->fts_info = FTS_NSOK; 814 } else { 815 /* Build a file name for fts_stat to stat. */ 816 if (ISSET(FTS_NOCHDIR)) { 817 p->fts_accpath = p->fts_path; 818 memmove(cp, p->fts_name, p->fts_namelen + 1); 819 } else 820 p->fts_accpath = p->fts_name; 821 /* Stat it. */ 822 p->fts_info = fts_stat(sp, p, 0); 823 824 /* Decrement link count if applicable. */ 825 if (nlinks > 0 && (p->fts_info == FTS_D || 826 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 827 --nlinks; 828 } 829 830 /* We walk in directory order so "ls -f" doesn't get upset. */ 831 p->fts_link = NULL; 832 if (head == NULL) 833 head = tail = p; 834 else { 835 tail->fts_link = p; 836 tail = p; 837 } 838 ++nitems; 839 } 840 if (dirp) 841 (void)closedir(dirp); 842 843 /* 844 * If realloc() changed the address of the path, adjust the 845 * addresses for the rest of the tree and the dir list. 846 */ 847 if (doadjust) 848 fts_padjust(sp, head); 849 850 /* 851 * If not changing directories, reset the path back to original 852 * state. 853 */ 854 if (ISSET(FTS_NOCHDIR)) { 855 if (len == sp->fts_pathlen || nitems == 0) 856 --cp; 857 *cp = '\0'; 858 } 859 860 /* 861 * If descended after called from fts_children or after called from 862 * fts_read and nothing found, get back. At the root level we use 863 * the saved fd; if one of fts_open()'s arguments is a relative path 864 * to an empty directory, we wind up here with no other way back. If 865 * can't get back, we're done. 866 */ 867 if (descend && (type == BCHILD || !nitems) && 868 (cur->fts_level == FTS_ROOTLEVEL ? 869 FCHDIR(sp, sp->fts_rfd) : 870 fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) { 871 cur->fts_info = FTS_ERR; 872 SET(FTS_STOP); 873 return (NULL); 874 } 875 876 /* If didn't find anything, return NULL. */ 877 if (!nitems) { 878 if (type == BREAD) 879 cur->fts_info = FTS_DP; 880 return (NULL); 881 } 882 883 /* Sort the entries. */ 884 if (sp->fts_compar && nitems > 1) 885 head = fts_sort(sp, head, nitems); 886 return (head); 887 } 888 889 static u_short 890 fts_stat(FTS *sp, FTSENT *p, int follow) 891 { 892 FTSENT *t; 893 dev_t dev; 894 ino_t ino; 895 struct stat *sbp, sb; 896 int saved_errno; 897 898 /* If user needs stat info, stat buffer already allocated. */ 899 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 900 901 #ifdef FTS_WHITEOUT 902 /* Check for whiteout. */ 903 if (p->fts_flags & FTS_ISW) { 904 if (sbp != &sb) { 905 memset(sbp, '\0', sizeof(*sbp)); 906 sbp->st_mode = S_IFWHT; 907 } 908 return (FTS_W); 909 } 910 #endif 911 912 /* 913 * If doing a logical walk, or application requested FTS_FOLLOW, do 914 * a stat(2). If that fails, check for a non-existent symlink. If 915 * fail, set the errno from the stat call. 916 */ 917 if (ISSET(FTS_LOGICAL) || follow) { 918 if (stat(p->fts_accpath, sbp)) { 919 saved_errno = errno; 920 if (!lstat(p->fts_accpath, sbp)) { 921 errno = 0; 922 return (FTS_SLNONE); 923 } 924 p->fts_errno = saved_errno; 925 goto err; 926 } 927 } else if (lstat(p->fts_accpath, sbp)) { 928 p->fts_errno = errno; 929 err: memset(sbp, 0, sizeof(struct stat)); 930 return (FTS_NS); 931 } 932 933 if (S_ISDIR(sbp->st_mode)) { 934 /* 935 * Set the device/inode. Used to find cycles and check for 936 * crossing mount points. Also remember the link count, used 937 * in fts_build to limit the number of stat calls. It is 938 * understood that these fields are only referenced if fts_info 939 * is set to FTS_D. 940 */ 941 dev = p->fts_dev = sbp->st_dev; 942 ino = p->fts_ino = sbp->st_ino; 943 p->fts_nlink = sbp->st_nlink; 944 945 if (ISDOT(p->fts_name)) 946 return (FTS_DOT); 947 948 /* 949 * Cycle detection is done by brute force when the directory 950 * is first encountered. If the tree gets deep enough or the 951 * number of symbolic links to directories is high enough, 952 * something faster might be worthwhile. 953 */ 954 for (t = p->fts_parent; 955 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 956 if (ino == t->fts_ino && dev == t->fts_dev) { 957 p->fts_cycle = t; 958 return (FTS_DC); 959 } 960 return (FTS_D); 961 } 962 if (S_ISLNK(sbp->st_mode)) 963 return (FTS_SL); 964 if (S_ISREG(sbp->st_mode)) 965 return (FTS_F); 966 return (FTS_DEFAULT); 967 } 968 969 /* 970 * The comparison function takes pointers to pointers to FTSENT structures. 971 * Qsort wants a comparison function that takes pointers to void. 972 * (Both with appropriate levels of const-poisoning, of course!) 973 * Use a trampoline function to deal with the difference. 974 */ 975 static int 976 fts_compar(const void *a, const void *b) 977 { 978 FTS *parent; 979 980 parent = (*(const FTSENT * const *)a)->fts_fts; 981 return (*parent->fts_compar)(a, b); 982 } 983 984 static FTSENT * 985 fts_sort(FTS *sp, FTSENT *head, int nitems) 986 { 987 FTSENT **ap, *p; 988 989 /* 990 * Construct an array of pointers to the structures and call qsort(3). 991 * Reassemble the array in the order returned by qsort. If unable to 992 * sort for memory reasons, return the directory entries in their 993 * current order. Allocate enough space for the current needs plus 994 * 40 so don't realloc one entry at a time. 995 */ 996 if (nitems > sp->fts_nitems) { 997 sp->fts_nitems = nitems + 40; 998 if ((sp->fts_array = reallocf(sp->fts_array, 999 sp->fts_nitems * sizeof(FTSENT *))) == NULL) { 1000 sp->fts_nitems = 0; 1001 return (head); 1002 } 1003 } 1004 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 1005 *ap++ = p; 1006 qsort(sp->fts_array, nitems, sizeof(FTSENT *), fts_compar); 1007 for (head = *(ap = sp->fts_array); --nitems; ++ap) 1008 ap[0]->fts_link = ap[1]; 1009 ap[0]->fts_link = NULL; 1010 return (head); 1011 } 1012 1013 static FTSENT * 1014 fts_alloc(FTS *sp, char *name, int namelen) 1015 { 1016 FTSENT *p; 1017 size_t len; 1018 1019 struct ftsent_withstat { 1020 FTSENT ent; 1021 struct stat statbuf; 1022 }; 1023 1024 /* 1025 * The file name is a variable length array and no stat structure is 1026 * necessary if the user has set the nostat bit. Allocate the FTSENT 1027 * structure, the file name and the stat structure in one chunk, but 1028 * be careful that the stat structure is reasonably aligned. 1029 */ 1030 if (ISSET(FTS_NOSTAT)) 1031 len = sizeof(FTSENT) + namelen + 1; 1032 else 1033 len = sizeof(struct ftsent_withstat) + namelen + 1; 1034 1035 if ((p = malloc(len)) == NULL) 1036 return (NULL); 1037 1038 if (ISSET(FTS_NOSTAT)) { 1039 p->fts_name = (char *)(p + 1); 1040 p->fts_statp = NULL; 1041 } else { 1042 p->fts_name = (char *)((struct ftsent_withstat *)p + 1); 1043 p->fts_statp = &((struct ftsent_withstat *)p)->statbuf; 1044 } 1045 1046 /* Copy the name and guarantee NUL termination. */ 1047 memcpy(p->fts_name, name, namelen); 1048 p->fts_name[namelen] = '\0'; 1049 p->fts_namelen = namelen; 1050 p->fts_path = sp->fts_path; 1051 p->fts_errno = 0; 1052 p->fts_flags = 0; 1053 p->fts_instr = FTS_NOINSTR; 1054 p->fts_number = 0; 1055 p->fts_pointer = NULL; 1056 p->fts_fts = sp; 1057 return (p); 1058 } 1059 1060 static void 1061 fts_lfree(FTSENT *head) 1062 { 1063 FTSENT *p; 1064 1065 /* Free a linked list of structures. */ 1066 while ((p = head)) { 1067 head = head->fts_link; 1068 free(p); 1069 } 1070 } 1071 1072 /* 1073 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 1074 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 1075 * though the kernel won't resolve them. Add the size (not just what's needed) 1076 * plus 256 bytes so don't realloc the path 2 bytes at a time. 1077 */ 1078 static int 1079 fts_palloc(FTS *sp, size_t more) 1080 { 1081 1082 sp->fts_pathlen += more + 256; 1083 /* 1084 * Check for possible wraparound. In an FTS, fts_pathlen is 1085 * a signed int but in an FTSENT it is an unsigned short. 1086 * We limit fts_pathlen to USHRT_MAX to be safe in both cases. 1087 */ 1088 if (sp->fts_pathlen < 0 || sp->fts_pathlen >= USHRT_MAX) { 1089 if (sp->fts_path) 1090 free(sp->fts_path); 1091 sp->fts_path = NULL; 1092 errno = ENAMETOOLONG; 1093 return (1); 1094 } 1095 sp->fts_path = reallocf(sp->fts_path, sp->fts_pathlen); 1096 return (sp->fts_path == NULL); 1097 } 1098 1099 /* 1100 * When the path is realloc'd, have to fix all of the pointers in structures 1101 * already returned. 1102 */ 1103 static void 1104 fts_padjust(FTS *sp, FTSENT *head) 1105 { 1106 FTSENT *p; 1107 char *addr = sp->fts_path; 1108 1109 #define ADJUST(p) do { \ 1110 if ((p)->fts_accpath != (p)->fts_name) { \ 1111 (p)->fts_accpath = \ 1112 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \ 1113 } \ 1114 (p)->fts_path = addr; \ 1115 } while (0) 1116 /* Adjust the current set of children. */ 1117 for (p = sp->fts_child; p; p = p->fts_link) 1118 ADJUST(p); 1119 1120 /* Adjust the rest of the tree, including the current level. */ 1121 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) { 1122 ADJUST(p); 1123 p = p->fts_link ? p->fts_link : p->fts_parent; 1124 } 1125 } 1126 1127 static size_t 1128 fts_maxarglen(char * const *argv) 1129 { 1130 size_t len, max; 1131 1132 for (max = 0; *argv; ++argv) 1133 if ((len = strlen(*argv)) > max) 1134 max = len; 1135 return (max + 1); 1136 } 1137 1138 /* 1139 * Change to dir specified by fd or p->fts_accpath without getting 1140 * tricked by someone changing the world out from underneath us. 1141 * Assumes p->fts_dev and p->fts_ino are filled in. 1142 */ 1143 static int 1144 fts_safe_changedir(FTS *sp, FTSENT *p, int fd, char *path) 1145 { 1146 int ret, oerrno, newfd; 1147 struct stat sb; 1148 1149 newfd = fd; 1150 if (ISSET(FTS_NOCHDIR)) 1151 return (0); 1152 if (fd < 0 && (newfd = _open(path, O_RDONLY | O_CLOEXEC, 0)) < 0) 1153 return (-1); 1154 if (_fstat(newfd, &sb)) { 1155 ret = -1; 1156 goto bail; 1157 } 1158 if (p->fts_dev != sb.st_dev || p->fts_ino != sb.st_ino) { 1159 errno = ENOENT; /* disinformation */ 1160 ret = -1; 1161 goto bail; 1162 } 1163 ret = fchdir(newfd); 1164 bail: 1165 oerrno = errno; 1166 if (fd < 0) 1167 (void)_close(newfd); 1168 errno = oerrno; 1169 return (ret); 1170 } 1171 1172 /* 1173 * Check if the filesystem for "ent" has UFS-style links. 1174 */ 1175 static int 1176 fts_ufslinks(FTS *sp, const FTSENT *ent) 1177 { 1178 struct _fts_private *priv; 1179 const char **cpp; 1180 1181 priv = (struct _fts_private *)sp; 1182 /* 1183 * If this node's device is different from the previous, grab 1184 * the filesystem information, and decide on the reliability 1185 * of the link information from this filesystem for stat(2) 1186 * avoidance. 1187 */ 1188 if (priv->ftsp_dev != ent->fts_dev) { 1189 if (statfs(ent->fts_path, &priv->ftsp_statfs) != -1) { 1190 priv->ftsp_dev = ent->fts_dev; 1191 priv->ftsp_linksreliable = 0; 1192 for (cpp = ufslike_filesystems; *cpp; cpp++) { 1193 if (strcmp(priv->ftsp_statfs.f_fstypename, 1194 *cpp) == 0) { 1195 priv->ftsp_linksreliable = 1; 1196 break; 1197 } 1198 } 1199 } else { 1200 priv->ftsp_linksreliable = 0; 1201 } 1202 } 1203 return (priv->ftsp_linksreliable); 1204 } 1205 1206 __sym_compat(fts_open, __fts_open_44bsd, FBSD_1.0); 1207 __sym_compat(fts_close, __fts_close_44bsd, FBSD_1.0); 1208 __sym_compat(fts_read, __fts_read_44bsd, FBSD_1.0); 1209 __sym_compat(fts_set, __fts_set_44bsd, FBSD_1.0); 1210 __sym_compat(fts_children, __fts_children_44bsd, FBSD_1.0); 1211 __sym_compat(fts_get_clientptr, __fts_get_clientptr_44bsd, FBSD_1.0); 1212 __sym_compat(fts_get_stream, __fts_get_stream_44bsd, FBSD_1.0); 1213 __sym_compat(fts_set_clientptr, __fts_set_clientptr_44bsd, FBSD_1.0); 1214