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