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) 34static 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 57FTSENT *__fts_children_44bsd(FTS *, int); 58int __fts_close_44bsd(FTS *); 59void *__fts_get_clientptr_44bsd(FTS *); 60FTS *__fts_get_stream_44bsd(FTSENT *); 61FTS *__fts_open_44bsd(char * const *, int, 62 int (*)(const FTSENT * const *, const FTSENT * const *)); 63FTSENT *__fts_read_44bsd(FTS *); 64int __fts_set_44bsd(FTS *, FTSENT *, int); 65void __fts_set_clientptr_44bsd(FTS *, void *); 66 67static FTSENT *fts_alloc(FTS *, char *, int); 68static FTSENT *fts_build(FTS *, int); 69static void fts_lfree(FTSENT *); 70static void fts_load(FTS *, FTSENT *); 71static size_t fts_maxarglen(char * const *); 72static void fts_padjust(FTS *, FTSENT *); 73static int fts_palloc(FTS *, size_t); 74static FTSENT *fts_sort(FTS *, FTSENT *, int); 75static u_short fts_stat(FTS *, FTSENT *, int); 76static int fts_safe_changedir(FTS *, FTSENT *, int, char *); 77static 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 */ 97struct _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 113static const char *ufslike_filesystems[] = { 114 "ufs", 115 "zfs", 116 "nfs", 117 "ext2fs", 118 0 119}; 120 121FTS * 122__fts_open_44bsd(char * const *argv, int options, 123 int (*compar)(const FTSENT * const *, const FTSENT * const *)) 124{ 125 struct _fts_private *priv; 126 FTS *sp; 127 FTSENT *p, *root; 128 int nitems; 129 FTSENT *parent, *tmp; 130 int len; 131 132 /* Options check. */ 133 if (options & ~FTS_OPTIONMASK) { 134 errno = EINVAL; 135 return (NULL); 136 } 137 138 /* Allocate/initialize the stream. */ 139 if ((priv = calloc(1, sizeof(*priv))) == NULL) 140 return (NULL); 141 sp = &priv->ftsp_fts; 142 sp->fts_compar = compar; 143 sp->fts_options = options; 144 145 /* Shush, GCC. */ 146 tmp = NULL; 147 148 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 149 if (ISSET(FTS_LOGICAL)) 150 SET(FTS_NOCHDIR); 151 152 /* 153 * Start out with 1K of path space, and enough, in any case, 154 * to hold the user's paths. 155 */ 156 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN))) 157 goto mem1; 158 159 /* Allocate/initialize root's parent. */ 160 if ((parent = fts_alloc(sp, "", 0)) == NULL) 161 goto mem2; 162 parent->fts_level = FTS_ROOTPARENTLEVEL; 163 164 /* Allocate/initialize root(s). */ 165 for (root = NULL, nitems = 0; *argv != NULL; ++argv, ++nitems) { 166 /* Don't allow zero-length paths. */ 167 if ((len = strlen(*argv)) == 0) { 168 errno = ENOENT; 169 goto mem3; 170 } 171 172 p = fts_alloc(sp, *argv, len); 173 p->fts_level = FTS_ROOTLEVEL; 174 p->fts_parent = parent; 175 p->fts_accpath = p->fts_name; 176 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 177 178 /* Command-line "." and ".." are real directories. */ 179 if (p->fts_info == FTS_DOT) 180 p->fts_info = FTS_D; 181 182 /* 183 * If comparison routine supplied, traverse in sorted 184 * order; otherwise traverse in the order specified. 185 */ 186 if (compar) { 187 p->fts_link = root; 188 root = p; 189 } else { 190 p->fts_link = NULL; 191 if (root == NULL) 192 tmp = root = p; 193 else { 194 tmp->fts_link = p; 195 tmp = p; 196 } 197 } 198 } 199 if (compar && nitems > 1) 200 root = fts_sort(sp, root, nitems); 201 202 /* 203 * Allocate a dummy pointer and make fts_read think that we've just 204 * finished the node before the root(s); set p->fts_info to FTS_INIT 205 * so that everything about the "current" node is ignored. 206 */ 207 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 208 goto mem3; 209 sp->fts_cur->fts_link = root; 210 sp->fts_cur->fts_info = FTS_INIT; 211 212 /* 213 * If using chdir(2), grab a file descriptor pointing to dot to ensure 214 * that we can get back here; this could be avoided for some paths, 215 * but almost certainly not worth the effort. Slashes, symbolic links, 216 * and ".." are all fairly nasty problems. Note, if we can't get the 217 * descriptor we run anyway, just more slowly. 218 */ 219 if (!ISSET(FTS_NOCHDIR) && 220 (sp->fts_rfd = _open(".", O_RDONLY | O_CLOEXEC, 0)) < 0) 221 SET(FTS_NOCHDIR); 222 223 return (sp); 224 225mem3: fts_lfree(root); 226 free(parent); 227mem2: free(sp->fts_path); 228mem1: free(sp); 229 return (NULL); 230} 231 232static void 233fts_load(FTS *sp, FTSENT *p) 234{ 235 int len; 236 char *cp; 237 238 /* 239 * Load the stream structure for the next traversal. Since we don't 240 * actually enter the directory until after the preorder visit, set 241 * the fts_accpath field specially so the chdir gets done to the right 242 * place and the user can access the first node. From fts_open it's 243 * known that the path will fit. 244 */ 245 len = p->fts_pathlen = p->fts_namelen; 246 memmove(sp->fts_path, p->fts_name, len + 1); 247 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 248 len = strlen(++cp); 249 memmove(p->fts_name, cp, len + 1); 250 p->fts_namelen = len; 251 } 252 p->fts_accpath = p->fts_path = sp->fts_path; 253 sp->fts_dev = p->fts_dev; 254} 255 256int 257__fts_close_44bsd(FTS *sp) 258{ 259 FTSENT *freep, *p; 260 int saved_errno; 261 262 /* 263 * This still works if we haven't read anything -- the dummy structure 264 * points to the root list, so we step through to the end of the root 265 * list which has a valid parent pointer. 266 */ 267 if (sp->fts_cur) { 268 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 269 freep = p; 270 p = p->fts_link != NULL ? p->fts_link : p->fts_parent; 271 free(freep); 272 } 273 free(p); 274 } 275 276 /* Free up child linked list, sort array, path buffer. */ 277 if (sp->fts_child) 278 fts_lfree(sp->fts_child); 279 if (sp->fts_array) 280 free(sp->fts_array); 281 free(sp->fts_path); 282 283 /* Return to original directory, save errno if necessary. */ 284 if (!ISSET(FTS_NOCHDIR)) { 285 saved_errno = fchdir(sp->fts_rfd) ? errno : 0; 286 (void)_close(sp->fts_rfd); 287 288 /* Set errno and return. */ 289 if (saved_errno != 0) { 290 /* Free up the stream pointer. */ 291 free(sp); 292 errno = saved_errno; 293 return (-1); 294 } 295 } 296 297 /* Free up the stream pointer. */ 298 free(sp); 299 return (0); 300} 301 302/* 303 * Special case of "/" at the end of the path so that slashes aren't 304 * appended which would cause paths to be written as "....//foo". 305 */ 306#define NAPPEND(p) \ 307 (p->fts_path[p->fts_pathlen - 1] == '/' \ 308 ? p->fts_pathlen - 1 : p->fts_pathlen) 309 310FTSENT * 311__fts_read_44bsd(FTS *sp) 312{ 313 FTSENT *p, *tmp; 314 int instr; 315 char *t; 316 int saved_errno; 317 318 /* If finished or unrecoverable error, return NULL. */ 319 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 320 return (NULL); 321 322 /* Set current node pointer. */ 323 p = sp->fts_cur; 324 325 /* Save and zero out user instructions. */ 326 instr = p->fts_instr; 327 p->fts_instr = FTS_NOINSTR; 328 329 /* Any type of file may be re-visited; re-stat and re-turn. */ 330 if (instr == FTS_AGAIN) { 331 p->fts_info = fts_stat(sp, p, 0); 332 return (p); 333 } 334 335 /* 336 * Following a symlink -- SLNONE test allows application to see 337 * SLNONE and recover. If indirecting through a symlink, have 338 * keep a pointer to current location. If unable to get that 339 * pointer, follow fails. 340 */ 341 if (instr == FTS_FOLLOW && 342 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 343 p->fts_info = fts_stat(sp, p, 1); 344 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 345 if ((p->fts_symfd = _open(".", O_RDONLY | O_CLOEXEC, 346 0)) < 0) { 347 p->fts_errno = errno; 348 p->fts_info = FTS_ERR; 349 } else 350 p->fts_flags |= FTS_SYMFOLLOW; 351 } 352 return (p); 353 } 354 355 /* Directory in pre-order. */ 356 if (p->fts_info == FTS_D) { 357 /* If skipped or crossed mount point, do post-order visit. */ 358 if (instr == FTS_SKIP || 359 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) { 360 if (p->fts_flags & FTS_SYMFOLLOW) 361 (void)_close(p->fts_symfd); 362 if (sp->fts_child) { 363 fts_lfree(sp->fts_child); 364 sp->fts_child = NULL; 365 } 366 p->fts_info = FTS_DP; 367 return (p); 368 } 369 370 /* Rebuild if only read the names and now traversing. */ 371 if (sp->fts_child != NULL && ISSET(FTS_NAMEONLY)) { 372 CLR(FTS_NAMEONLY); 373 fts_lfree(sp->fts_child); 374 sp->fts_child = NULL; 375 } 376 377 /* 378 * Cd to the subdirectory. 379 * 380 * If have already read and now fail to chdir, whack the list 381 * to make the names come out right, and set the parent errno 382 * so the application will eventually get an error condition. 383 * Set the FTS_DONTCHDIR flag so that when we logically change 384 * directories back to the parent we don't do a chdir. 385 * 386 * If haven't read do so. If the read fails, fts_build sets 387 * FTS_STOP or the fts_info field of the node. 388 */ 389 if (sp->fts_child != NULL) { 390 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) { 391 p->fts_errno = errno; 392 p->fts_flags |= FTS_DONTCHDIR; 393 for (p = sp->fts_child; p != NULL; 394 p = p->fts_link) 395 p->fts_accpath = 396 p->fts_parent->fts_accpath; 397 } 398 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 399 if (ISSET(FTS_STOP)) 400 return (NULL); 401 return (p); 402 } 403 p = sp->fts_child; 404 sp->fts_child = NULL; 405 goto name; 406 } 407 408 /* Move to the next node on this level. */ 409next: tmp = p; 410 if ((p = p->fts_link) != NULL) { 411 free(tmp); 412 413 /* 414 * If reached the top, return to the original directory (or 415 * the root of the tree), and load the paths for the next root. 416 */ 417 if (p->fts_level == FTS_ROOTLEVEL) { 418 if (FCHDIR(sp, sp->fts_rfd)) { 419 SET(FTS_STOP); 420 return (NULL); 421 } 422 fts_load(sp, p); 423 return (sp->fts_cur = p); 424 } 425 426 /* 427 * User may have called fts_set on the node. If skipped, 428 * ignore. If followed, get a file descriptor so we can 429 * get back if necessary. 430 */ 431 if (p->fts_instr == FTS_SKIP) 432 goto next; 433 if (p->fts_instr == FTS_FOLLOW) { 434 p->fts_info = fts_stat(sp, p, 1); 435 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 436 if ((p->fts_symfd = 437 _open(".", O_RDONLY | O_CLOEXEC, 0)) < 0) { 438 p->fts_errno = errno; 439 p->fts_info = FTS_ERR; 440 } else 441 p->fts_flags |= FTS_SYMFOLLOW; 442 } 443 p->fts_instr = FTS_NOINSTR; 444 } 445 446name: t = sp->fts_path + NAPPEND(p->fts_parent); 447 *t++ = '/'; 448 memmove(t, p->fts_name, p->fts_namelen + 1); 449 return (sp->fts_cur = p); 450 } 451 452 /* Move up to the parent node. */ 453 p = tmp->fts_parent; 454 free(tmp); 455 456 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 457 /* 458 * Done; free everything up and set errno to 0 so the user 459 * can distinguish between error and EOF. 460 */ 461 free(p); 462 errno = 0; 463 return (sp->fts_cur = NULL); 464 } 465 466 /* NUL terminate the pathname. */ 467 sp->fts_path[p->fts_pathlen] = '\0'; 468 469 /* 470 * Return to the parent directory. If at a root node or came through 471 * a symlink, go back through the file descriptor. Otherwise, cd up 472 * one directory. 473 */ 474 if (p->fts_level == FTS_ROOTLEVEL) { 475 if (FCHDIR(sp, sp->fts_rfd)) { 476 SET(FTS_STOP); 477 return (NULL); 478 } 479 } else if (p->fts_flags & FTS_SYMFOLLOW) { 480 if (FCHDIR(sp, p->fts_symfd)) { 481 saved_errno = errno; 482 (void)_close(p->fts_symfd); 483 errno = saved_errno; 484 SET(FTS_STOP); 485 return (NULL); 486 } 487 (void)_close(p->fts_symfd); 488 } else if (!(p->fts_flags & FTS_DONTCHDIR) && 489 fts_safe_changedir(sp, p->fts_parent, -1, "..")) { 490 SET(FTS_STOP); 491 return (NULL); 492 } 493 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 494 return (sp->fts_cur = p); 495} 496 497/* 498 * Fts_set takes the stream as an argument although it's not used in this 499 * implementation; it would be necessary if anyone wanted to add global 500 * semantics to fts using fts_set. An error return is allowed for similar 501 * reasons. 502 */ 503/* ARGSUSED */ 504int 505__fts_set_44bsd(FTS *sp, FTSENT *p, int instr) 506{ 507 if (instr != 0 && instr != FTS_AGAIN && instr != FTS_FOLLOW && 508 instr != FTS_NOINSTR && instr != FTS_SKIP) { 509 errno = EINVAL; 510 return (1); 511 } 512 p->fts_instr = instr; 513 return (0); 514} 515 516FTSENT * 517__fts_children_44bsd(FTS *sp, int instr) 518{ 519 FTSENT *p; 520 int fd; 521 522 if (instr != 0 && instr != FTS_NAMEONLY) { 523 errno = EINVAL; 524 return (NULL); 525 } 526 527 /* Set current node pointer. */ 528 p = sp->fts_cur; 529 530 /* 531 * Errno set to 0 so user can distinguish empty directory from 532 * an error. 533 */ 534 errno = 0; 535 536 /* Fatal errors stop here. */ 537 if (ISSET(FTS_STOP)) 538 return (NULL); 539 540 /* Return logical hierarchy of user's arguments. */ 541 if (p->fts_info == FTS_INIT) 542 return (p->fts_link); 543 544 /* 545 * If not a directory being visited in pre-order, stop here. Could 546 * allow FTS_DNR, assuming the user has fixed the problem, but the 547 * same effect is available with FTS_AGAIN. 548 */ 549 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 550 return (NULL); 551 552 /* Free up any previous child list. */ 553 if (sp->fts_child != NULL) 554 fts_lfree(sp->fts_child); 555 556 if (instr == FTS_NAMEONLY) { 557 SET(FTS_NAMEONLY); 558 instr = BNAMES; 559 } else 560 instr = BCHILD; 561 562 /* 563 * If using chdir on a relative path and called BEFORE fts_read does 564 * its chdir to the root of a traversal, we can lose -- we need to 565 * chdir into the subdirectory, and we don't know where the current 566 * directory is, so we can't get back so that the upcoming chdir by 567 * fts_read will work. 568 */ 569 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 570 ISSET(FTS_NOCHDIR)) 571 return (sp->fts_child = fts_build(sp, instr)); 572 573 if ((fd = _open(".", O_RDONLY | O_CLOEXEC, 0)) < 0) 574 return (NULL); 575 sp->fts_child = fts_build(sp, instr); 576 if (fchdir(fd)) { 577 (void)_close(fd); 578 return (NULL); 579 } 580 (void)_close(fd); 581 return (sp->fts_child); 582} 583 584#ifndef fts_get_clientptr 585#error "fts_get_clientptr not defined" 586#endif 587 588void * 589(__fts_get_clientptr_44bsd)(FTS *sp) 590{ 591 592 return (fts_get_clientptr(sp)); 593} 594 595#ifndef fts_get_stream 596#error "fts_get_stream not defined" 597#endif 598 599FTS * 600(__fts_get_stream_44bsd)(FTSENT *p) 601{ 602 return (fts_get_stream(p)); 603} 604 605void 606__fts_set_clientptr_44bsd(FTS *sp, void *clientptr) 607{ 608 609 sp->fts_clientptr = clientptr; 610} 611 612/* 613 * This is the tricky part -- do not casually change *anything* in here. The 614 * idea is to build the linked list of entries that are used by fts_children 615 * and fts_read. There are lots of special cases. 616 * 617 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 618 * set and it's a physical walk (so that symbolic links can't be directories), 619 * we can do things quickly. First, if it's a 4.4BSD file system, the type 620 * of the file is in the directory entry. Otherwise, we assume that the number 621 * of subdirectories in a node is equal to the number of links to the parent. 622 * The former skips all stat calls. The latter skips stat calls in any leaf 623 * directories and for any files after the subdirectories in the directory have 624 * been found, cutting the stat calls by about 2/3. 625 */ 626static FTSENT * 627fts_build(FTS *sp, int type) 628{ 629 struct dirent *dp; 630 FTSENT *p, *head; 631 int nitems; 632 FTSENT *cur, *tail; 633 DIR *dirp; 634 void *oldaddr; 635 size_t dnamlen; 636 int cderrno, descend, len, level, maxlen, nlinks, oflag, saved_errno, 637 nostat, doadjust; 638 char *cp; 639 640 /* Set current node pointer. */ 641 cur = sp->fts_cur; 642 643 /* 644 * Open the directory for reading. If this fails, we're done. 645 * If being called from fts_read, set the fts_info field. 646 */ 647#ifdef FTS_WHITEOUT 648 if (ISSET(FTS_WHITEOUT)) 649 oflag = DTF_NODUP | DTF_REWIND; 650 else 651 oflag = DTF_HIDEW | DTF_NODUP | DTF_REWIND; 652#else 653#define __opendir2(path, flag) opendir(path) 654#endif 655 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 656 if (type == BREAD) { 657 cur->fts_info = FTS_DNR; 658 cur->fts_errno = errno; 659 } 660 return (NULL); 661 } 662 663 /* 664 * Nlinks is the number of possible entries of type directory in the 665 * directory if we're cheating on stat calls, 0 if we're not doing 666 * any stat calls at all, -1 if we're doing stats on everything. 667 */ 668 if (type == BNAMES) { 669 nlinks = 0; 670 /* Be quiet about nostat, GCC. */ 671 nostat = 0; 672 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) { 673 if (fts_ufslinks(sp, cur)) 674 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 675 else 676 nlinks = -1; 677 nostat = 1; 678 } else { 679 nlinks = -1; 680 nostat = 0; 681 } 682 683#ifdef notdef 684 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 685 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 686 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 687#endif 688 /* 689 * If we're going to need to stat anything or we want to descend 690 * and stay in the directory, chdir. If this fails we keep going, 691 * but set a flag so we don't chdir after the post-order visit. 692 * We won't be able to stat anything, but we can still return the 693 * names themselves. Note, that since fts_read won't be able to 694 * chdir into the directory, it will have to return different path 695 * names than before, i.e. "a/b" instead of "b". Since the node 696 * has already been visited in pre-order, have to wait until the 697 * post-order visit to return the error. There is a special case 698 * here, if there was nothing to stat then it's not an error to 699 * not be able to stat. This is all fairly nasty. If a program 700 * needed sorted entries or stat information, they had better be 701 * checking FTS_NS on the returned nodes. 702 */ 703 cderrno = 0; 704 if (nlinks || type == BREAD) { 705 if (fts_safe_changedir(sp, cur, _dirfd(dirp), NULL)) { 706 if (nlinks && type == BREAD) 707 cur->fts_errno = errno; 708 cur->fts_flags |= FTS_DONTCHDIR; 709 descend = 0; 710 cderrno = errno; 711 } else 712 descend = 1; 713 } else 714 descend = 0; 715 716 /* 717 * Figure out the max file name length that can be stored in the 718 * current path -- the inner loop allocates more path as necessary. 719 * We really wouldn't have to do the maxlen calculations here, we 720 * could do them in fts_read before returning the path, but it's a 721 * lot easier here since the length is part of the dirent structure. 722 * 723 * If not changing directories set a pointer so that can just append 724 * each new name into the path. 725 */ 726 len = NAPPEND(cur); 727 if (ISSET(FTS_NOCHDIR)) { 728 cp = sp->fts_path + len; 729 *cp++ = '/'; 730 } else { 731 /* GCC, you're too verbose. */ 732 cp = NULL; 733 } 734 len++; 735 maxlen = sp->fts_pathlen - len; 736 737 level = cur->fts_level + 1; 738 739 /* Read the directory, attaching each entry to the `link' pointer. */ 740 doadjust = 0; 741 for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) { 742 dnamlen = dp->d_namlen; 743 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 744 continue; 745 746 if ((p = fts_alloc(sp, dp->d_name, (int)dnamlen)) == NULL) 747 goto mem1; 748 if (dnamlen >= maxlen) { /* include space for NUL */ 749 oldaddr = sp->fts_path; 750 if (fts_palloc(sp, dnamlen + len + 1)) { 751 /* 752 * No more memory for path or structures. Save 753 * errno, free up the current structure and the 754 * structures already allocated. 755 */ 756mem1: saved_errno = errno; 757 if (p) 758 free(p); 759 fts_lfree(head); 760 (void)closedir(dirp); 761 cur->fts_info = FTS_ERR; 762 SET(FTS_STOP); 763 errno = saved_errno; 764 return (NULL); 765 } 766 /* Did realloc() change the pointer? */ 767 if (oldaddr != sp->fts_path) { 768 doadjust = 1; 769 if (ISSET(FTS_NOCHDIR)) 770 cp = sp->fts_path + len; 771 } 772 maxlen = sp->fts_pathlen - len; 773 } 774 775 if (len + dnamlen >= USHRT_MAX) { 776 /* 777 * In an FTSENT, fts_pathlen is a u_short so it is 778 * possible to wraparound here. If we do, free up 779 * the current structure and the structures already 780 * allocated, then error out with ENAMETOOLONG. 781 */ 782 free(p); 783 fts_lfree(head); 784 (void)closedir(dirp); 785 cur->fts_info = FTS_ERR; 786 SET(FTS_STOP); 787 errno = ENAMETOOLONG; 788 return (NULL); 789 } 790 p->fts_level = level; 791 p->fts_parent = sp->fts_cur; 792 p->fts_pathlen = len + dnamlen; 793 794#ifdef FTS_WHITEOUT 795 if (dp->d_type == DT_WHT) 796 p->fts_flags |= FTS_ISW; 797#endif 798 799 if (cderrno) { 800 if (nlinks) { 801 p->fts_info = FTS_NS; 802 p->fts_errno = cderrno; 803 } else 804 p->fts_info = FTS_NSOK; 805 p->fts_accpath = cur->fts_accpath; 806 } else if (nlinks == 0 807#ifdef DT_DIR 808 || (nostat && 809 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN) 810#endif 811 ) { 812 p->fts_accpath = 813 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 814 p->fts_info = FTS_NSOK; 815 } else { 816 /* Build a file name for fts_stat to stat. */ 817 if (ISSET(FTS_NOCHDIR)) { 818 p->fts_accpath = p->fts_path; 819 memmove(cp, p->fts_name, p->fts_namelen + 1); 820 } else 821 p->fts_accpath = p->fts_name; 822 /* Stat it. */ 823 p->fts_info = fts_stat(sp, p, 0); 824 825 /* Decrement link count if applicable. */ 826 if (nlinks > 0 && (p->fts_info == FTS_D || 827 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 828 --nlinks; 829 } 830 831 /* We walk in directory order so "ls -f" doesn't get upset. */ 832 p->fts_link = NULL; 833 if (head == NULL) 834 head = tail = p; 835 else { 836 tail->fts_link = p; 837 tail = p; 838 } 839 ++nitems; 840 } 841 if (dirp) 842 (void)closedir(dirp); 843 844 /* 845 * If realloc() changed the address of the path, adjust the 846 * addresses for the rest of the tree and the dir list. 847 */ 848 if (doadjust) 849 fts_padjust(sp, head); 850 851 /* 852 * If not changing directories, reset the path back to original 853 * state. 854 */ 855 if (ISSET(FTS_NOCHDIR)) { 856 if (len == sp->fts_pathlen || nitems == 0) 857 --cp; 858 *cp = '\0'; 859 } 860 861 /* 862 * If descended after called from fts_children or after called from 863 * fts_read and nothing found, get back. At the root level we use 864 * the saved fd; if one of fts_open()'s arguments is a relative path 865 * to an empty directory, we wind up here with no other way back. If 866 * can't get back, we're done. 867 */ 868 if (descend && (type == BCHILD || !nitems) && 869 (cur->fts_level == FTS_ROOTLEVEL ? 870 FCHDIR(sp, sp->fts_rfd) : 871 fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) { 872 cur->fts_info = FTS_ERR; 873 SET(FTS_STOP); 874 return (NULL); 875 } 876 877 /* If didn't find anything, return NULL. */ 878 if (!nitems) { 879 if (type == BREAD) 880 cur->fts_info = FTS_DP; 881 return (NULL); 882 } 883 884 /* Sort the entries. */ 885 if (sp->fts_compar && nitems > 1) 886 head = fts_sort(sp, head, nitems); 887 return (head); 888} 889 890static u_short 891fts_stat(FTS *sp, FTSENT *p, int follow) 892{ 893 FTSENT *t; 894 dev_t dev; 895 ino_t ino; 896 struct stat *sbp, sb; 897 int saved_errno; 898 899 /* If user needs stat info, stat buffer already allocated. */ 900 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 901 902#ifdef FTS_WHITEOUT 903 /* Check for whiteout. */ 904 if (p->fts_flags & FTS_ISW) { 905 if (sbp != &sb) { 906 memset(sbp, '\0', sizeof(*sbp)); 907 sbp->st_mode = S_IFWHT; 908 } 909 return (FTS_W); 910 } 911#endif 912 913 /* 914 * If doing a logical walk, or application requested FTS_FOLLOW, do 915 * a stat(2). If that fails, check for a non-existent symlink. If 916 * fail, set the errno from the stat call. 917 */ 918 if (ISSET(FTS_LOGICAL) || follow) { 919 if (stat(p->fts_accpath, sbp)) { 920 saved_errno = errno; 921 if (!lstat(p->fts_accpath, sbp)) { 922 errno = 0; 923 return (FTS_SLNONE); 924 } 925 p->fts_errno = saved_errno; 926 goto err; 927 } 928 } else if (lstat(p->fts_accpath, sbp)) { 929 p->fts_errno = errno; 930err: memset(sbp, 0, sizeof(struct stat)); 931 return (FTS_NS); 932 } 933 934 if (S_ISDIR(sbp->st_mode)) { 935 /* 936 * Set the device/inode. Used to find cycles and check for 937 * crossing mount points. Also remember the link count, used 938 * in fts_build to limit the number of stat calls. It is 939 * understood that these fields are only referenced if fts_info 940 * is set to FTS_D. 941 */ 942 dev = p->fts_dev = sbp->st_dev; 943 ino = p->fts_ino = sbp->st_ino; 944 p->fts_nlink = sbp->st_nlink; 945 946 if (ISDOT(p->fts_name)) 947 return (FTS_DOT); 948 949 /* 950 * Cycle detection is done by brute force when the directory 951 * is first encountered. If the tree gets deep enough or the 952 * number of symbolic links to directories is high enough, 953 * something faster might be worthwhile. 954 */ 955 for (t = p->fts_parent; 956 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 957 if (ino == t->fts_ino && dev == t->fts_dev) { 958 p->fts_cycle = t; 959 return (FTS_DC); 960 } 961 return (FTS_D); 962 } 963 if (S_ISLNK(sbp->st_mode)) 964 return (FTS_SL); 965 if (S_ISREG(sbp->st_mode)) 966 return (FTS_F); 967 return (FTS_DEFAULT); 968} 969 970/* 971 * The comparison function takes pointers to pointers to FTSENT structures. 972 * Qsort wants a comparison function that takes pointers to void. 973 * (Both with appropriate levels of const-poisoning, of course!) 974 * Use a trampoline function to deal with the difference. 975 */ 976static int 977fts_compar(const void *a, const void *b) 978{ 979 FTS *parent; 980 981 parent = (*(const FTSENT * const *)a)->fts_fts; 982 return (*parent->fts_compar)(a, b); 983} 984 985static FTSENT * 986fts_sort(FTS *sp, FTSENT *head, int nitems) 987{ 988 FTSENT **ap, *p; 989 990 /* 991 * Construct an array of pointers to the structures and call qsort(3). 992 * Reassemble the array in the order returned by qsort. If unable to 993 * sort for memory reasons, return the directory entries in their 994 * current order. Allocate enough space for the current needs plus 995 * 40 so don't realloc one entry at a time. 996 */ 997 if (nitems > sp->fts_nitems) { 998 sp->fts_nitems = nitems + 40; 999 if ((sp->fts_array = reallocf(sp->fts_array, 1000 sp->fts_nitems * sizeof(FTSENT *))) == NULL) { 1001 sp->fts_nitems = 0; 1002 return (head); 1003 } 1004 } 1005 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 1006 *ap++ = p; 1007 qsort(sp->fts_array, nitems, sizeof(FTSENT *), fts_compar); 1008 for (head = *(ap = sp->fts_array); --nitems; ++ap) 1009 ap[0]->fts_link = ap[1]; 1010 ap[0]->fts_link = NULL; 1011 return (head); 1012} 1013 1014static FTSENT * 1015fts_alloc(FTS *sp, char *name, int namelen) 1016{ 1017 FTSENT *p; 1018 size_t len; 1019 1020 struct ftsent_withstat { 1021 FTSENT ent; 1022 struct stat statbuf; 1023 }; 1024 1025 /* 1026 * The file name is a variable length array and no stat structure is 1027 * necessary if the user has set the nostat bit. Allocate the FTSENT 1028 * structure, the file name and the stat structure in one chunk, but 1029 * be careful that the stat structure is reasonably aligned. 1030 */ 1031 if (ISSET(FTS_NOSTAT)) 1032 len = sizeof(FTSENT) + namelen + 1; 1033 else 1034 len = sizeof(struct ftsent_withstat) + namelen + 1; 1035 1036 if ((p = malloc(len)) == NULL) 1037 return (NULL); 1038 1039 if (ISSET(FTS_NOSTAT)) { 1040 p->fts_name = (char *)(p + 1); 1041 p->fts_statp = NULL; 1042 } else { 1043 p->fts_name = (char *)((struct ftsent_withstat *)p + 1); 1044 p->fts_statp = &((struct ftsent_withstat *)p)->statbuf; 1045 } 1046 1047 /* Copy the name and guarantee NUL termination. */ 1048 memcpy(p->fts_name, name, namelen); 1049 p->fts_name[namelen] = '\0'; 1050 p->fts_namelen = namelen; 1051 p->fts_path = sp->fts_path; 1052 p->fts_errno = 0; 1053 p->fts_flags = 0; 1054 p->fts_instr = FTS_NOINSTR; 1055 p->fts_number = 0; 1056 p->fts_pointer = NULL; 1057 p->fts_fts = sp; 1058 return (p); 1059} 1060 1061static void 1062fts_lfree(FTSENT *head) 1063{ 1064 FTSENT *p; 1065 1066 /* Free a linked list of structures. */ 1067 while ((p = head)) { 1068 head = head->fts_link; 1069 free(p); 1070 } 1071} 1072 1073/* 1074 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 1075 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 1076 * though the kernel won't resolve them. Add the size (not just what's needed) 1077 * plus 256 bytes so don't realloc the path 2 bytes at a time. 1078 */ 1079static int 1080fts_palloc(FTS *sp, size_t more) 1081{ 1082 1083 sp->fts_pathlen += more + 256; 1084 /* 1085 * Check for possible wraparound. In an FTS, fts_pathlen is 1086 * a signed int but in an FTSENT it is an unsigned short. 1087 * We limit fts_pathlen to USHRT_MAX to be safe in both cases. 1088 */ 1089 if (sp->fts_pathlen < 0 || sp->fts_pathlen >= USHRT_MAX) { 1090 if (sp->fts_path) 1091 free(sp->fts_path); 1092 sp->fts_path = NULL; 1093 errno = ENAMETOOLONG; 1094 return (1); 1095 } 1096 sp->fts_path = reallocf(sp->fts_path, sp->fts_pathlen); 1097 return (sp->fts_path == NULL); 1098} 1099 1100/* 1101 * When the path is realloc'd, have to fix all of the pointers in structures 1102 * already returned. 1103 */ 1104static void 1105fts_padjust(FTS *sp, FTSENT *head) 1106{ 1107 FTSENT *p; 1108 char *addr = sp->fts_path; 1109 1110#define ADJUST(p) do { \ 1111 if ((p)->fts_accpath != (p)->fts_name) { \ 1112 (p)->fts_accpath = \ 1113 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \ 1114 } \ 1115 (p)->fts_path = addr; \ 1116} while (0) 1117 /* Adjust the current set of children. */ 1118 for (p = sp->fts_child; p; p = p->fts_link) 1119 ADJUST(p); 1120 1121 /* Adjust the rest of the tree, including the current level. */ 1122 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) { 1123 ADJUST(p); 1124 p = p->fts_link ? p->fts_link : p->fts_parent; 1125 } 1126} 1127 1128static size_t 1129fts_maxarglen(char * const *argv) 1130{ 1131 size_t len, max; 1132 1133 for (max = 0; *argv; ++argv) 1134 if ((len = strlen(*argv)) > max) 1135 max = len; 1136 return (max + 1); 1137} 1138 1139/* 1140 * Change to dir specified by fd or p->fts_accpath without getting 1141 * tricked by someone changing the world out from underneath us. 1142 * Assumes p->fts_dev and p->fts_ino are filled in. 1143 */ 1144static int 1145fts_safe_changedir(FTS *sp, FTSENT *p, int fd, char *path) 1146{ 1147 int ret, oerrno, newfd; 1148 struct stat sb; 1149 1150 newfd = fd; 1151 if (ISSET(FTS_NOCHDIR)) 1152 return (0); 1153 if (fd < 0 && (newfd = _open(path, O_RDONLY | O_CLOEXEC, 0)) < 0) 1154 return (-1); 1155 if (_fstat(newfd, &sb)) { 1156 ret = -1; 1157 goto bail; 1158 } 1159 if (p->fts_dev != sb.st_dev || p->fts_ino != sb.st_ino) { 1160 errno = ENOENT; /* disinformation */ 1161 ret = -1; 1162 goto bail; 1163 } 1164 ret = fchdir(newfd); 1165bail: 1166 oerrno = errno; 1167 if (fd < 0) 1168 (void)_close(newfd); 1169 errno = oerrno; 1170 return (ret); 1171} 1172 1173/* 1174 * Check if the filesystem for "ent" has UFS-style links. 1175 */ 1176static int 1177fts_ufslinks(FTS *sp, const FTSENT *ent) 1178{ 1179 struct _fts_private *priv; 1180 const char **cpp; 1181 1182 priv = (struct _fts_private *)sp; 1183 /* 1184 * If this node's device is different from the previous, grab 1185 * the filesystem information, and decide on the reliability 1186 * of the link information from this filesystem for stat(2) 1187 * avoidance. 1188 */ 1189 if (priv->ftsp_dev != ent->fts_dev) { 1190 if (statfs(ent->fts_path, &priv->ftsp_statfs) != -1) { 1191 priv->ftsp_dev = ent->fts_dev; 1192 priv->ftsp_linksreliable = 0; 1193 for (cpp = ufslike_filesystems; *cpp; cpp++) { 1194 if (strcmp(priv->ftsp_statfs.f_fstypename, 1195 *cpp) == 0) { 1196 priv->ftsp_linksreliable = 1; 1197 break; 1198 } 1199 } 1200 } else { 1201 priv->ftsp_linksreliable = 0; 1202 } 1203 } 1204 return (priv->ftsp_linksreliable); 1205} 1206 1207__sym_compat(fts_open, __fts_open_44bsd, FBSD_1.0); 1208__sym_compat(fts_close, __fts_close_44bsd, FBSD_1.0); 1209__sym_compat(fts_read, __fts_read_44bsd, FBSD_1.0); 1210__sym_compat(fts_set, __fts_set_44bsd, FBSD_1.0); 1211__sym_compat(fts_children, __fts_children_44bsd, FBSD_1.0); 1212__sym_compat(fts_get_clientptr, __fts_get_clientptr_44bsd, FBSD_1.0); 1213__sym_compat(fts_get_stream, __fts_get_stream_44bsd, FBSD_1.0); 1214__sym_compat(fts_set_clientptr, __fts_set_clientptr_44bsd, FBSD_1.0); 1215