fts.c revision 1.29
1/* $NetBSD: fts.c,v 1.29 2005/12/11 04:12:58 christos Exp $ */ 2 3/*- 4 * Copyright (c) 1990, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32#if HAVE_NBTOOL_CONFIG_H 33#include "nbtool_config.h" 34#endif 35 36#include <sys/cdefs.h> 37#if defined(LIBC_SCCS) && !defined(lint) 38#if 0 39static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94"; 40#else 41__RCSID("$NetBSD: fts.c,v 1.29 2005/12/11 04:12:58 christos Exp $"); 42#endif 43#endif /* LIBC_SCCS and not lint */ 44 45#include "namespace.h" 46#include <sys/param.h> 47#include <sys/stat.h> 48 49#include <assert.h> 50#include <dirent.h> 51#include <errno.h> 52#include <fcntl.h> 53#include <fts.h> 54#include <stdlib.h> 55#include <string.h> 56#include <unistd.h> 57 58#if ! HAVE_NBTOOL_CONFIG_H 59#define HAVE_STRUCT_DIRENT_D_NAMLEN 1 60#endif 61 62static FTSENT *fts_alloc(FTS *, const char *, size_t); 63static FTSENT *fts_build(FTS *, int); 64static void fts_lfree(FTSENT *); 65static void fts_load(FTS *, FTSENT *); 66static size_t fts_maxarglen(char * const *); 67static size_t fts_pow2(size_t); 68static int fts_palloc(FTS *, size_t); 69static void fts_padjust(FTS *, FTSENT *); 70static FTSENT *fts_sort(FTS *, FTSENT *, size_t); 71static u_short fts_stat(FTS *, FTSENT *, int); 72static int fts_safe_changedir(const FTS *, const FTSENT *, int, 73 const char *); 74 75#define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2]))) 76 77#define CLR(opt) (sp->fts_options &= ~(opt)) 78#define ISSET(opt) (sp->fts_options & (opt)) 79#define SET(opt) (sp->fts_options |= (opt)) 80 81#define CHDIR(sp, path) (!ISSET(FTS_NOCHDIR) && chdir(path)) 82#define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) && fchdir(fd)) 83 84/* fts_build flags */ 85#define BCHILD 1 /* fts_children */ 86#define BNAMES 2 /* fts_children, names only */ 87#define BREAD 3 /* fts_read */ 88 89#ifndef DTF_HIDEW 90#undef FTS_WHITEOUT 91#endif 92 93FTS * 94fts_open(char * const *argv, int options, 95 int (*compar)(const FTSENT **, const FTSENT **)) 96{ 97 FTS *sp; 98 FTSENT *p, *root; 99 size_t nitems; 100 FTSENT *parent, *tmp = NULL; /* pacify gcc */ 101 size_t len; 102 103 _DIAGASSERT(argv != NULL); 104 105 /* Options check. */ 106 if (options & ~FTS_OPTIONMASK) { 107 errno = EINVAL; 108 return (NULL); 109 } 110 111 /* Allocate/initialize the stream */ 112 if ((sp = malloc((u_int)sizeof(FTS))) == NULL) 113 return (NULL); 114 memset(sp, 0, sizeof(FTS)); 115 sp->fts_compar = compar; 116 sp->fts_options = options; 117 118 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 119 if (ISSET(FTS_LOGICAL)) 120 SET(FTS_NOCHDIR); 121 122 /* 123 * Start out with 1K of path space, and enough, in any case, 124 * to hold the user's paths. 125 */ 126 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN))) 127 goto mem1; 128 129 /* Allocate/initialize root's parent. */ 130 if ((parent = fts_alloc(sp, "", 0)) == NULL) 131 goto mem2; 132 parent->fts_level = FTS_ROOTPARENTLEVEL; 133 134 /* Allocate/initialize root(s). */ 135 for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) { 136 /* Don't allow zero-length paths. */ 137 if ((len = strlen(*argv)) == 0) { 138 errno = ENOENT; 139 goto mem3; 140 } 141 142 if ((p = fts_alloc(sp, *argv, len)) == NULL) 143 goto mem3; 144 p->fts_level = FTS_ROOTLEVEL; 145 p->fts_parent = parent; 146 p->fts_accpath = p->fts_name; 147 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 148 149 /* Command-line "." and ".." are real directories. */ 150 if (p->fts_info == FTS_DOT) 151 p->fts_info = FTS_D; 152 153 /* 154 * If comparison routine supplied, traverse in sorted 155 * order; otherwise traverse in the order specified. 156 */ 157 if (compar) { 158 p->fts_link = root; 159 root = p; 160 } else { 161 p->fts_link = NULL; 162 if (root == NULL) 163 tmp = root = p; 164 else { 165 tmp->fts_link = p; 166 tmp = p; 167 } 168 } 169 } 170 if (compar && nitems > 1) 171 root = fts_sort(sp, root, nitems); 172 173 /* 174 * Allocate a dummy pointer and make fts_read think that we've just 175 * finished the node before the root(s); set p->fts_info to FTS_INIT 176 * so that everything about the "current" node is ignored. 177 */ 178 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 179 goto mem3; 180 sp->fts_cur->fts_link = root; 181 sp->fts_cur->fts_info = FTS_INIT; 182 183 /* 184 * If using chdir(2), grab a file descriptor pointing to dot to insure 185 * that we can get back here; this could be avoided for some paths, 186 * but almost certainly not worth the effort. Slashes, symbolic links, 187 * and ".." are all fairly nasty problems. Note, if we can't get the 188 * descriptor we run anyway, just more slowly. 189 */ 190 if (!ISSET(FTS_NOCHDIR)) { 191 if ((sp->fts_rfd = open(".", O_RDONLY, 0)) == -1) 192 SET(FTS_NOCHDIR); 193 else if (fcntl(sp->fts_rfd, F_SETFD, FD_CLOEXEC) == -1) { 194 close(sp->fts_rfd); 195 SET(FTS_NOCHDIR); 196 } 197 } 198 199 return (sp); 200 201mem3: fts_lfree(root); 202 free(parent); 203mem2: free(sp->fts_path); 204mem1: free(sp); 205 return (NULL); 206} 207 208static void 209fts_load(FTS *sp, FTSENT *p) 210{ 211 size_t len; 212 char *cp; 213 214 _DIAGASSERT(sp != NULL); 215 _DIAGASSERT(p != NULL); 216 217 /* 218 * Load the stream structure for the next traversal. Since we don't 219 * actually enter the directory until after the preorder visit, set 220 * the fts_accpath field specially so the chdir gets done to the right 221 * place and the user can access the first node. From fts_open it's 222 * known that the path will fit. 223 */ 224 len = p->fts_pathlen = p->fts_namelen; 225 memmove(sp->fts_path, p->fts_name, len + 1); 226 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 227 len = strlen(++cp); 228 memmove(p->fts_name, cp, len + 1); 229 p->fts_namelen = len; 230 } 231 p->fts_accpath = p->fts_path = sp->fts_path; 232 sp->fts_dev = p->fts_dev; 233} 234 235int 236fts_close(FTS *sp) 237{ 238 FTSENT *freep, *p; 239 int saved_errno = 0; 240 241 _DIAGASSERT(sp != NULL); 242 243 /* 244 * This still works if we haven't read anything -- the dummy structure 245 * points to the root list, so we step through to the end of the root 246 * list which has a valid parent pointer. 247 */ 248 if (sp->fts_cur) { 249 if (ISSET(FTS_SYMFOLLOW)) 250 (void)close(sp->fts_cur->fts_symfd); 251 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 252 freep = p; 253 p = p->fts_link ? p->fts_link : p->fts_parent; 254 free(freep); 255 } 256 free(p); 257 } 258 259 /* Free up child linked list, sort array, path buffer. */ 260 if (sp->fts_child) 261 fts_lfree(sp->fts_child); 262 if (sp->fts_array) 263 free(sp->fts_array); 264 free(sp->fts_path); 265 266 /* Return to original directory, save errno if necessary. */ 267 if (!ISSET(FTS_NOCHDIR)) { 268 if (fchdir(sp->fts_rfd) == -1) 269 saved_errno = errno; 270 (void)close(sp->fts_rfd); 271 } 272 273 /* Free up the stream pointer. */ 274 free(sp); 275 if (saved_errno) { 276 errno = saved_errno; 277 return -1; 278 } 279 280 return 0; 281} 282 283#if !defined(__FTS_COMPAT_TAILINGSLASH) 284 285/* 286 * Special case of "/" at the end of the path so that slashes aren't 287 * appended which would cause paths to be written as "....//foo". 288 */ 289#define NAPPEND(p) \ 290 (p->fts_path[p->fts_pathlen - 1] == '/' \ 291 ? p->fts_pathlen - 1 : p->fts_pathlen) 292 293#else /* !defined(__FTS_COMPAT_TAILINGSLASH) */ 294 295/* 296 * compatibility with the old behaviour. 297 * 298 * Special case a root of "/" so that slashes aren't appended which would 299 * cause paths to be written as "//foo". 300 */ 301 302#define NAPPEND(p) \ 303 (p->fts_level == FTS_ROOTLEVEL && p->fts_pathlen == 1 && \ 304 p->fts_path[0] == '/' ? 0 : p->fts_pathlen) 305 306#endif /* !defined(__FTS_COMPAT_TAILINGSLASH) */ 307 308FTSENT * 309fts_read(FTS *sp) 310{ 311 FTSENT *p, *tmp; 312 int instr; 313 char *t; 314 int saved_errno; 315 316 _DIAGASSERT(sp != NULL); 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, 0)) == -1) { 346 p->fts_errno = errno; 347 p->fts_info = FTS_ERR; 348 } else if (fcntl(p->fts_symfd, F_SETFD, FD_CLOEXEC) == -1) { 349 p->fts_errno = errno; 350 p->fts_info = FTS_ERR; 351 close(p->fts_symfd); 352 } else 353 p->fts_flags |= FTS_SYMFOLLOW; 354 } 355 return (p); 356 } 357 358 /* Directory in pre-order. */ 359 if (p->fts_info == FTS_D) { 360 /* If skipped or crossed mount point, do post-order visit. */ 361 if (instr == FTS_SKIP || 362 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) { 363 if (p->fts_flags & FTS_SYMFOLLOW) 364 (void)close(p->fts_symfd); 365 if (sp->fts_child) { 366 fts_lfree(sp->fts_child); 367 sp->fts_child = NULL; 368 } 369 p->fts_info = FTS_DP; 370 return (p); 371 } 372 373 /* Rebuild if only read the names and now traversing. */ 374 if (sp->fts_child && ISSET(FTS_NAMEONLY)) { 375 CLR(FTS_NAMEONLY); 376 fts_lfree(sp->fts_child); 377 sp->fts_child = NULL; 378 } 379 380 /* 381 * Cd to the subdirectory. 382 * 383 * If have already read and now fail to chdir, whack the list 384 * to make the names come out right, and set the parent errno 385 * so the application will eventually get an error condition. 386 * Set the FTS_DONTCHDIR flag so that when we logically change 387 * directories back to the parent we don't do a chdir. 388 * 389 * If haven't read do so. If the read fails, fts_build sets 390 * FTS_STOP or the fts_info field of the node. 391 */ 392 if (sp->fts_child) { 393 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) { 394 p->fts_errno = errno; 395 p->fts_flags |= FTS_DONTCHDIR; 396 for (p = sp->fts_child; p; p = p->fts_link) 397 p->fts_accpath = 398 p->fts_parent->fts_accpath; 399 } 400 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 401 if (ISSET(FTS_STOP)) 402 return (NULL); 403 return (p); 404 } 405 p = sp->fts_child; 406 sp->fts_child = NULL; 407 goto name; 408 } 409 410 /* Move to the next node on this level. */ 411next: tmp = p; 412 if ((p = p->fts_link) != NULL) { 413 free(tmp); 414 415 /* 416 * If reached the top, return to the original directory, and 417 * load the paths for the next root. 418 */ 419 if (p->fts_level == FTS_ROOTLEVEL) { 420 if (FCHDIR(sp, sp->fts_rfd)) { 421 SET(FTS_STOP); 422 return (NULL); 423 } 424 fts_load(sp, p); 425 return (sp->fts_cur = p); 426 } 427 428 /* 429 * User may have called fts_set on the node. If skipped, 430 * ignore. If followed, get a file descriptor so we can 431 * get back if necessary. 432 */ 433 if (p->fts_instr == FTS_SKIP) 434 goto next; 435 if (p->fts_instr == FTS_FOLLOW) { 436 p->fts_info = fts_stat(sp, p, 1); 437 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 438 if ((p->fts_symfd = 439 open(".", O_RDONLY, 0)) == -1) { 440 p->fts_errno = errno; 441 p->fts_info = FTS_ERR; 442 } else if (fcntl(p->fts_symfd, F_SETFD, FD_CLOEXEC) == -1) { 443 p->fts_errno = errno; 444 p->fts_info = FTS_ERR; 445 close(p->fts_symfd); 446 } else 447 p->fts_flags |= FTS_SYMFOLLOW; 448 } 449 p->fts_instr = FTS_NOINSTR; 450 } 451 452name: t = sp->fts_path + NAPPEND(p->fts_parent); 453 *t++ = '/'; 454 memmove(t, p->fts_name, (size_t)(p->fts_namelen + 1)); 455 return (sp->fts_cur = p); 456 } 457 458 /* Move up to the parent node. */ 459 p = tmp->fts_parent; 460 free(tmp); 461 462 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 463 /* 464 * Done; free everything up and set errno to 0 so the user 465 * can distinguish between error and EOF. 466 */ 467 free(p); 468 errno = 0; 469 return (sp->fts_cur = NULL); 470 } 471 472 /* Nul terminate the pathname. */ 473 sp->fts_path[p->fts_pathlen] = '\0'; 474 475 /* 476 * Return to the parent directory. If at a root node or came through 477 * a symlink, go back through the file descriptor. Otherwise, cd up 478 * one directory. 479 */ 480 if (p->fts_level == FTS_ROOTLEVEL) { 481 if (FCHDIR(sp, sp->fts_rfd)) { 482 SET(FTS_STOP); 483 return (NULL); 484 } 485 } else if (p->fts_flags & FTS_SYMFOLLOW) { 486 if (FCHDIR(sp, p->fts_symfd)) { 487 saved_errno = errno; 488 (void)close(p->fts_symfd); 489 errno = saved_errno; 490 SET(FTS_STOP); 491 return (NULL); 492 } 493 (void)close(p->fts_symfd); 494 } else if (!(p->fts_flags & FTS_DONTCHDIR) && 495 fts_safe_changedir(sp, p->fts_parent, -1, "..")) { 496 SET(FTS_STOP); 497 return (NULL); 498 } 499 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 500 return (sp->fts_cur = p); 501} 502 503/* 504 * Fts_set takes the stream as an argument although it's not used in this 505 * implementation; it would be necessary if anyone wanted to add global 506 * semantics to fts using fts_set. An error return is allowed for similar 507 * reasons. 508 */ 509/* ARGSUSED */ 510int 511fts_set(FTS *sp, FTSENT *p, int instr) 512{ 513 514 _DIAGASSERT(sp != NULL); 515 _DIAGASSERT(p != NULL); 516 517 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW && 518 instr != FTS_NOINSTR && instr != FTS_SKIP) { 519 errno = EINVAL; 520 return (1); 521 } 522 p->fts_instr = instr; 523 return (0); 524} 525 526FTSENT * 527fts_children(FTS *sp, int instr) 528{ 529 FTSENT *p; 530 int fd; 531 532 _DIAGASSERT(sp != NULL); 533 534 if (instr && instr != FTS_NAMEONLY) { 535 errno = EINVAL; 536 return (NULL); 537 } 538 539 /* Set current node pointer. */ 540 p = sp->fts_cur; 541 542 /* 543 * Errno set to 0 so user can distinguish empty directory from 544 * an error. 545 */ 546 errno = 0; 547 548 /* Fatal errors stop here. */ 549 if (ISSET(FTS_STOP)) 550 return (NULL); 551 552 /* Return logical hierarchy of user's arguments. */ 553 if (p->fts_info == FTS_INIT) 554 return (p->fts_link); 555 556 /* 557 * If not a directory being visited in pre-order, stop here. Could 558 * allow FTS_DNR, assuming the user has fixed the problem, but the 559 * same effect is available with FTS_AGAIN. 560 */ 561 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 562 return (NULL); 563 564 /* Free up any previous child list. */ 565 if (sp->fts_child) 566 fts_lfree(sp->fts_child); 567 568 if (instr == FTS_NAMEONLY) { 569 SET(FTS_NAMEONLY); 570 instr = BNAMES; 571 } else 572 instr = BCHILD; 573 574 /* 575 * If using chdir on a relative path and called BEFORE fts_read does 576 * its chdir to the root of a traversal, we can lose -- we need to 577 * chdir into the subdirectory, and we don't know where the current 578 * directory is, so we can't get back so that the upcoming chdir by 579 * fts_read will work. 580 */ 581 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 582 ISSET(FTS_NOCHDIR)) 583 return (sp->fts_child = fts_build(sp, instr)); 584 585 if ((fd = open(".", O_RDONLY, 0)) == -1) 586 return (sp->fts_child = NULL); 587 sp->fts_child = fts_build(sp, instr); 588 if (fchdir(fd)) { 589 (void)close(fd); 590 return (NULL); 591 } 592 (void)close(fd); 593 return (sp->fts_child); 594} 595 596/* 597 * This is the tricky part -- do not casually change *anything* in here. The 598 * idea is to build the linked list of entries that are used by fts_children 599 * and fts_read. There are lots of special cases. 600 * 601 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 602 * set and it's a physical walk (so that symbolic links can't be directories), 603 * we can do things quickly. First, if it's a 4.4BSD file system, the type 604 * of the file is in the directory entry. Otherwise, we assume that the number 605 * of subdirectories in a node is equal to the number of links to the parent. 606 * The former skips all stat calls. The latter skips stat calls in any leaf 607 * directories and for any files after the subdirectories in the directory have 608 * been found, cutting the stat calls by about 2/3. 609 */ 610static FTSENT * 611fts_build(FTS *sp, int type) 612{ 613 struct dirent *dp; 614 FTSENT *p, *head; 615 size_t nitems; 616 FTSENT *cur, *tail; 617 DIR *dirp; 618 void *oldaddr; 619 size_t dnamlen; 620 int cderrno, descend, len, level, nlinks, saved_errno, nostat, doadjust; 621 size_t maxlen; 622#ifdef FTS_WHITEOUT 623 int oflag; 624#endif 625 char *cp = NULL; /* pacify gcc */ 626 627 _DIAGASSERT(sp != NULL); 628 629 /* Set current node pointer. */ 630 cur = sp->fts_cur; 631 632 /* 633 * Open the directory for reading. If this fails, we're done. 634 * If being called from fts_read, set the fts_info field. 635 */ 636#ifdef FTS_WHITEOUT 637 if (ISSET(FTS_WHITEOUT)) 638 oflag = DTF_NODUP|DTF_REWIND; 639 else 640 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND; 641#else 642#define __opendir2(path, flag) opendir(path) 643#endif 644 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 645 if (type == BREAD) { 646 cur->fts_info = FTS_DNR; 647 cur->fts_errno = errno; 648 } 649 return (NULL); 650 } 651 652 /* 653 * Nlinks is the number of possible entries of type directory in the 654 * directory if we're cheating on stat calls, 0 if we're not doing 655 * any stat calls at all, -1 if we're doing stats on everything. 656 */ 657 if (type == BNAMES) { 658 nlinks = 0; 659 nostat = 1; 660 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) { 661 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 662 nostat = 1; 663 } else { 664 nlinks = -1; 665 nostat = 0; 666 } 667 668#ifdef notdef 669 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 670 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 671 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 672#endif 673 /* 674 * If we're going to need to stat anything or we want to descend 675 * and stay in the directory, chdir. If this fails we keep going, 676 * but set a flag so we don't chdir after the post-order visit. 677 * We won't be able to stat anything, but we can still return the 678 * names themselves. Note, that since fts_read won't be able to 679 * chdir into the directory, it will have to return different path 680 * names than before, i.e. "a/b" instead of "b". Since the node 681 * has already been visited in pre-order, have to wait until the 682 * post-order visit to return the error. There is a special case 683 * here, if there was nothing to stat then it's not an error to 684 * not be able to stat. This is all fairly nasty. If a program 685 * needed sorted entries or stat information, they had better be 686 * checking FTS_NS on the returned nodes. 687 */ 688 cderrno = 0; 689 if (nlinks || type == BREAD) { 690 if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) { 691 if (nlinks && type == BREAD) 692 cur->fts_errno = errno; 693 cur->fts_flags |= FTS_DONTCHDIR; 694 descend = 0; 695 cderrno = errno; 696 } else 697 descend = 1; 698 } else 699 descend = 0; 700 701 /* 702 * Figure out the max file name length that can be stored in the 703 * current path -- the inner loop allocates more path as necessary. 704 * We really wouldn't have to do the maxlen calculations here, we 705 * could do them in fts_read before returning the path, but it's a 706 * lot easier here since the length is part of the dirent structure. 707 * 708 * If not changing directories set a pointer so that can just append 709 * each new name into the path. 710 */ 711 len = NAPPEND(cur); 712 if (ISSET(FTS_NOCHDIR)) { 713 cp = sp->fts_path + len; 714 *cp++ = '/'; 715 } 716 len++; 717 maxlen = sp->fts_pathlen - len; 718 719 level = cur->fts_level + 1; 720 721 /* Read the directory, attaching each entry to the `link' pointer. */ 722 doadjust = 0; 723 for (head = tail = NULL, nitems = 0; (dp = readdir(dirp)) != NULL;) { 724 725 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 726 continue; 727 728#if HAVE_STRUCT_DIRENT_D_NAMLEN 729 dnamlen = dp->d_namlen; 730#else 731 dnamlen = strlen(dp->d_name); 732#endif 733 if ((p = fts_alloc(sp, dp->d_name, dnamlen)) == NULL) 734 goto mem1; 735 if (dnamlen >= maxlen) { /* include space for NUL */ 736 oldaddr = sp->fts_path; 737 if (fts_palloc(sp, dnamlen + len + 1)) { 738 /* 739 * No more memory for path or structures. Save 740 * errno, free up the current structure and the 741 * structures already allocated. 742 */ 743mem1: saved_errno = errno; 744 if (p) 745 free(p); 746 fts_lfree(head); 747 (void)closedir(dirp); 748 errno = saved_errno; 749 cur->fts_info = FTS_ERR; 750 SET(FTS_STOP); 751 return (NULL); 752 } 753 /* Did realloc() change the pointer? */ 754 if (oldaddr != sp->fts_path) { 755 doadjust = 1; 756 if (ISSET(FTS_NOCHDIR)) 757 cp = sp->fts_path + len; 758 } 759 maxlen = sp->fts_pathlen - len; 760 } 761 762 if (len + dnamlen >= USHRT_MAX) { 763 /* 764 * In an FTSENT, fts_pathlen is a u_short so it is 765 * possible to wraparound here. If we do, free up 766 * the current structure and the structures already 767 * allocated, then error out with ENAMETOOLONG. 768 */ 769 free(p); 770 fts_lfree(head); 771 (void)closedir(dirp); 772 cur->fts_info = FTS_ERR; 773 SET(FTS_STOP); 774 errno = ENAMETOOLONG; 775 return (NULL); 776 } 777 p->fts_level = level; 778 p->fts_pathlen = len + dnamlen; 779 p->fts_parent = sp->fts_cur; 780 781#ifdef FTS_WHITEOUT 782 if (dp->d_type == DT_WHT) 783 p->fts_flags |= FTS_ISW; 784#endif 785 786 if (cderrno) { 787 if (nlinks) { 788 p->fts_info = FTS_NS; 789 p->fts_errno = cderrno; 790 } else 791 p->fts_info = FTS_NSOK; 792 p->fts_accpath = cur->fts_accpath; 793 } else if (nlinks == 0 794#ifdef DT_DIR 795 || (nostat && 796 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN) 797#endif 798 ) { 799 p->fts_accpath = 800 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 801 p->fts_info = FTS_NSOK; 802 } else { 803 /* Build a file name for fts_stat to stat. */ 804 if (ISSET(FTS_NOCHDIR)) { 805 p->fts_accpath = p->fts_path; 806 memmove(cp, p->fts_name, 807 (size_t)(p->fts_namelen + 1)); 808 } else 809 p->fts_accpath = p->fts_name; 810 /* Stat it. */ 811 p->fts_info = fts_stat(sp, p, 0); 812 813 /* Decrement link count if applicable. */ 814 if (nlinks > 0 && (p->fts_info == FTS_D || 815 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 816 --nlinks; 817 } 818 819 /* We walk in directory order so "ls -f" doesn't get upset. */ 820 p->fts_link = NULL; 821 if (head == NULL) 822 head = tail = p; 823 else { 824 tail->fts_link = p; 825 tail = p; 826 } 827 ++nitems; 828 } 829 (void)closedir(dirp); 830 831 /* 832 * If had to realloc the path, adjust the addresses for the rest 833 * of the tree. 834 */ 835 if (doadjust) 836 fts_padjust(sp, head); 837 838 /* 839 * If not changing directories, reset the path back to original 840 * state. 841 */ 842 if (ISSET(FTS_NOCHDIR)) { 843 if (len == sp->fts_pathlen || nitems == 0) 844 --cp; 845 *cp = '\0'; 846 } 847 848 /* 849 * If descended after called from fts_children or after called from 850 * fts_read and nothing found, get back. At the root level we use 851 * the saved fd; if one of fts_open()'s arguments is a relative path 852 * to an empty directory, we wind up here with no other way back. If 853 * can't get back, we're done. 854 */ 855 if (descend && (type == BCHILD || !nitems) && 856 (cur->fts_level == FTS_ROOTLEVEL ? 857 FCHDIR(sp, sp->fts_rfd) : 858 fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) { 859 cur->fts_info = FTS_ERR; 860 SET(FTS_STOP); 861 return (NULL); 862 } 863 864 /* If didn't find anything, return NULL. */ 865 if (!nitems) { 866 if (type == BREAD) 867 cur->fts_info = FTS_DP; 868 return (NULL); 869 } 870 871 /* Sort the entries. */ 872 if (sp->fts_compar && nitems > 1) 873 head = fts_sort(sp, head, nitems); 874 return (head); 875} 876 877static u_short 878fts_stat(FTS *sp, FTSENT *p, int follow) 879{ 880 FTSENT *t; 881 dev_t dev; 882 __fts_ino_t ino; 883 __fts_stat_t *sbp, sb; 884 int saved_errno; 885 886 _DIAGASSERT(sp != NULL); 887 _DIAGASSERT(p != NULL); 888 889 /* If user needs stat info, stat buffer already allocated. */ 890 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 891 892#ifdef FTS_WHITEOUT 893 /* check for whiteout */ 894 if (p->fts_flags & FTS_ISW) { 895 if (sbp != &sb) { 896 memset(sbp, '\0', sizeof (*sbp)); 897 sbp->st_mode = S_IFWHT; 898 } 899 return (FTS_W); 900 } 901#endif 902 903 /* 904 * If doing a logical walk, or application requested FTS_FOLLOW, do 905 * a stat(2). If that fails, check for a non-existent symlink. If 906 * fail, set the errno from the stat call. 907 */ 908 if (ISSET(FTS_LOGICAL) || follow) { 909 if (stat(p->fts_accpath, sbp)) { 910 saved_errno = errno; 911 if (!lstat(p->fts_accpath, sbp)) { 912 errno = 0; 913 return (FTS_SLNONE); 914 } 915 p->fts_errno = saved_errno; 916 goto err; 917 } 918 } else if (lstat(p->fts_accpath, sbp)) { 919 p->fts_errno = errno; 920err: memset(sbp, 0, sizeof(*sbp)); 921 return (FTS_NS); 922 } 923 924 if (S_ISDIR(sbp->st_mode)) { 925 /* 926 * Set the device/inode. Used to find cycles and check for 927 * crossing mount points. Also remember the link count, used 928 * in fts_build to limit the number of stat calls. It is 929 * understood that these fields are only referenced if fts_info 930 * is set to FTS_D. 931 */ 932 dev = p->fts_dev = sbp->st_dev; 933 ino = p->fts_ino = sbp->st_ino; 934 p->fts_nlink = sbp->st_nlink; 935 936 if (ISDOT(p->fts_name)) 937 return (FTS_DOT); 938 939 /* 940 * Cycle detection is done by brute force when the directory 941 * is first encountered. If the tree gets deep enough or the 942 * number of symbolic links to directories is high enough, 943 * something faster might be worthwhile. 944 */ 945 for (t = p->fts_parent; 946 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 947 if (ino == t->fts_ino && dev == t->fts_dev) { 948 p->fts_cycle = t; 949 return (FTS_DC); 950 } 951 return (FTS_D); 952 } 953 if (S_ISLNK(sbp->st_mode)) 954 return (FTS_SL); 955 if (S_ISREG(sbp->st_mode)) 956 return (FTS_F); 957 return (FTS_DEFAULT); 958} 959 960static FTSENT * 961fts_sort(FTS *sp, FTSENT *head, size_t nitems) 962{ 963 FTSENT **ap, *p; 964 965 _DIAGASSERT(sp != NULL); 966 _DIAGASSERT(head != NULL); 967 968 /* 969 * Construct an array of pointers to the structures and call qsort(3). 970 * Reassemble the array in the order returned by qsort. If unable to 971 * sort for memory reasons, return the directory entries in their 972 * current order. Allocate enough space for the current needs plus 973 * 40 so don't realloc one entry at a time. 974 */ 975 if (nitems > sp->fts_nitems) { 976 FTSENT **new; 977 978 new = realloc(sp->fts_array, sizeof(FTSENT *) * (nitems + 40)); 979 if (new == 0) 980 return (head); 981 sp->fts_array = new; 982 sp->fts_nitems = nitems + 40; 983 } 984 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 985 *ap++ = p; 986 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), 987 (int (*)(const void *, const void *))sp->fts_compar); 988 for (head = *(ap = sp->fts_array); --nitems; ++ap) 989 ap[0]->fts_link = ap[1]; 990 ap[0]->fts_link = NULL; 991 return (head); 992} 993 994static FTSENT * 995fts_alloc(FTS *sp, const char *name, size_t namelen) 996{ 997 FTSENT *p; 998 size_t len; 999 1000 _DIAGASSERT(sp != NULL); 1001 _DIAGASSERT(name != NULL); 1002 1003#if defined(ALIGNBYTES) && defined(ALIGN) 1004 /* 1005 * The file name is a variable length array and no stat structure is 1006 * necessary if the user has set the nostat bit. Allocate the FTSENT 1007 * structure, the file name and the stat structure in one chunk, but 1008 * be careful that the stat structure is reasonably aligned. Since the 1009 * fts_name field is declared to be of size 1, the fts_name pointer is 1010 * namelen + 2 before the first possible address of the stat structure. 1011 */ 1012 len = sizeof(FTSENT) + namelen; 1013 if (!ISSET(FTS_NOSTAT)) 1014 len += sizeof(*(p->fts_statp)) + ALIGNBYTES; 1015 if ((p = malloc(len)) == NULL) 1016 return (NULL); 1017 1018 if (!ISSET(FTS_NOSTAT)) 1019 p->fts_statp = 1020 (__fts_stat_t *)ALIGN((u_long)(p->fts_name + namelen + 2)); 1021#else 1022 if ((p = malloc(sizeof(FTSENT) + namelen)) == NULL) 1023 return (NULL); 1024 1025 if (!ISSET(FTS_NOSTAT)) 1026 if ((p->fts_statp = malloc(sizeof(*(p->fts_statp)))) == NULL) { 1027 free(p); 1028 return (NULL); 1029 } 1030#endif 1031 1032 /* Copy the name plus the trailing NULL. */ 1033 memmove(p->fts_name, name, namelen + 1); 1034 1035 p->fts_namelen = namelen; 1036 p->fts_path = sp->fts_path; 1037 p->fts_errno = 0; 1038 p->fts_flags = 0; 1039 p->fts_instr = FTS_NOINSTR; 1040 p->fts_number = 0; 1041 p->fts_pointer = NULL; 1042 return (p); 1043} 1044 1045static void 1046fts_lfree(FTSENT *head) 1047{ 1048 FTSENT *p; 1049 1050 /* XXX: head may be NULL ? */ 1051 1052 /* Free a linked list of structures. */ 1053 while ((p = head) != NULL) { 1054 head = head->fts_link; 1055 1056#if !defined(ALIGNBYTES) || !defined(ALIGN) 1057 if (p->fts_statp) 1058 free(p->fts_statp); 1059#endif 1060 free(p); 1061 } 1062} 1063 1064static size_t 1065fts_pow2(size_t x) 1066{ 1067 1068 x--; 1069 x |= x>>1; 1070 x |= x>>2; 1071 x |= x>>4; 1072 x |= x>>8; 1073 x |= x>>16; 1074#if LONG_BIT > 32 1075 x |= x>>32; 1076#endif 1077#if LONG_BIT > 64 1078 x |= x>>64; 1079#endif 1080 x++; 1081 return (x); 1082} 1083 1084/* 1085 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 1086 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 1087 * though the kernel won't resolve them. Round up the new size to a power of 2, 1088 * so we don't realloc the path 2 bytes at a time. 1089 */ 1090static int 1091fts_palloc(FTS *sp, size_t size) 1092{ 1093 char *new; 1094 1095 _DIAGASSERT(sp != NULL); 1096 1097#if 1 1098 /* Protect against fts_pathlen overflow. */ 1099 if (size > USHRT_MAX + 1) { 1100 errno = ENAMETOOLONG; 1101 return (1); 1102 } 1103#endif 1104 size = fts_pow2(size); 1105 new = realloc(sp->fts_path, size); 1106 if (new == 0) 1107 return (1); 1108 sp->fts_path = new; 1109 sp->fts_pathlen = size; 1110 return (0); 1111} 1112 1113/* 1114 * When the path is realloc'd, have to fix all of the pointers in structures 1115 * already returned. 1116 */ 1117static void 1118fts_padjust(FTS *sp, FTSENT *head) 1119{ 1120 FTSENT *p; 1121 char *addr; 1122 1123 _DIAGASSERT(sp != NULL); 1124 1125#define ADJUST(p) do { \ 1126 if ((p)->fts_accpath != (p)->fts_name) \ 1127 (p)->fts_accpath = \ 1128 addr + ((p)->fts_accpath - (p)->fts_path); \ 1129 (p)->fts_path = addr; \ 1130} while (/*CONSTCOND*/0) 1131 1132 addr = sp->fts_path; 1133 1134 /* Adjust the current set of children. */ 1135 for (p = sp->fts_child; p; p = p->fts_link) 1136 ADJUST(p); 1137 1138 /* Adjust the rest of the tree, including the current level. */ 1139 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) { 1140 ADJUST(p); 1141 p = p->fts_link ? p->fts_link : p->fts_parent; 1142 } 1143} 1144 1145static size_t 1146fts_maxarglen(char * const *argv) 1147{ 1148 size_t len, max; 1149 1150 _DIAGASSERT(argv != NULL); 1151 1152 for (max = 0; *argv; ++argv) 1153 if ((len = strlen(*argv)) > max) 1154 max = len; 1155 return (max + 1); 1156} 1157 1158/* 1159 * Change to dir specified by fd or p->fts_accpath without getting 1160 * tricked by someone changing the world out from underneath us. 1161 * Assumes p->fts_dev and p->fts_ino are filled in. 1162 */ 1163static int 1164fts_safe_changedir(const FTS *sp, const FTSENT *p, int fd, const char *path) 1165{ 1166 int oldfd = fd, ret = -1; 1167 __fts_stat_t sb; 1168 1169 if (ISSET(FTS_NOCHDIR)) 1170 return 0; 1171 1172 if (oldfd < 0 && (fd = open(path, O_RDONLY)) == -1) 1173 return -1; 1174 1175 if (fstat(fd, &sb) == -1) 1176 goto bail; 1177 1178 if (sb.st_ino != p->fts_ino || sb.st_dev != p->fts_dev) { 1179 errno = ENOENT; 1180 goto bail; 1181 } 1182 1183 ret = fchdir(fd); 1184 1185bail: 1186 if (oldfd < 0) { 1187 int save_errno = errno; 1188 (void)close(fd); 1189 errno = save_errno; 1190 } 1191 return ret; 1192} 1193