fts.c revision 1.33
1/* $NetBSD: fts.c,v 1.33 2008/09/20 00:14:12 lukem 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 1.33 2008/09/20 00:14:12 lukem 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 60#endif 61 62static FTSENT *fts_alloc(FTS *, const char *, size_t); 63static FTSENT *fts_build(FTS *, int); 64static void fts_free(FTSENT *); 65static void fts_lfree(FTSENT *); 66static void fts_load(FTS *, FTSENT *); 67static size_t fts_maxarglen(char * const *); 68static size_t fts_pow2(size_t); 69static int fts_palloc(FTS *, size_t); 70static void fts_padjust(FTS *, FTSENT *); 71static FTSENT *fts_sort(FTS *, FTSENT *, size_t); 72static unsigned short fts_stat(FTS *, FTSENT *, int); 73static int fts_safe_changedir(const FTS *, const FTSENT *, int, 74 const char *); 75 76#if defined(ALIGNBYTES) && defined(ALIGN) 77#define FTS_ALLOC_ALIGNED 1 78#else 79#undef FTS_ALLOC_ALIGNED 80#endif 81 82#define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2]))) 83 84#define CLR(opt) (sp->fts_options &= ~(opt)) 85#define ISSET(opt) (sp->fts_options & (opt)) 86#define SET(opt) (sp->fts_options |= (opt)) 87 88#define CHDIR(sp, path) (!ISSET(FTS_NOCHDIR) && chdir(path)) 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#ifndef DTF_HIDEW 97#undef FTS_WHITEOUT 98#endif 99 100FTS * 101fts_open(char * const *argv, int options, 102 int (*compar)(const FTSENT **, const FTSENT **)) 103{ 104 FTS *sp; 105 FTSENT *p, *root; 106 size_t nitems; 107 FTSENT *parent, *tmp = NULL; /* pacify gcc */ 108 size_t len; 109 110 _DIAGASSERT(argv != NULL); 111 112 /* Options check. */ 113 if (options & ~FTS_OPTIONMASK) { 114 errno = EINVAL; 115 return (NULL); 116 } 117 118 /* Allocate/initialize the stream */ 119 if ((sp = malloc((unsigned int)sizeof(FTS))) == NULL) 120 return (NULL); 121 memset(sp, 0, sizeof(FTS)); 122 sp->fts_compar = compar; 123 sp->fts_options = options; 124 125 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 126 if (ISSET(FTS_LOGICAL)) 127 SET(FTS_NOCHDIR); 128 129 /* 130 * Start out with 1K of path space, and enough, in any case, 131 * to hold the user's paths. 132 */ 133 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN))) 134 goto mem1; 135 136 /* Allocate/initialize root's parent. */ 137 if ((parent = fts_alloc(sp, "", 0)) == NULL) 138 goto mem2; 139 parent->fts_level = FTS_ROOTPARENTLEVEL; 140 141 /* Allocate/initialize root(s). */ 142 for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) { 143 /* Don't allow zero-length paths. */ 144 if ((len = strlen(*argv)) == 0) { 145 errno = ENOENT; 146 goto mem3; 147 } 148 149 if ((p = fts_alloc(sp, *argv, len)) == NULL) 150 goto mem3; 151 p->fts_level = FTS_ROOTLEVEL; 152 p->fts_parent = parent; 153 p->fts_accpath = p->fts_name; 154 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 155 156 /* Command-line "." and ".." are real directories. */ 157 if (p->fts_info == FTS_DOT) 158 p->fts_info = FTS_D; 159 160 /* 161 * If comparison routine supplied, traverse in sorted 162 * order; otherwise traverse in the order specified. 163 */ 164 if (compar) { 165 p->fts_link = root; 166 root = p; 167 } else { 168 p->fts_link = NULL; 169 if (root == NULL) 170 tmp = root = p; 171 else { 172 tmp->fts_link = p; 173 tmp = p; 174 } 175 } 176 } 177 if (compar && nitems > 1) 178 root = fts_sort(sp, root, nitems); 179 180 /* 181 * Allocate a dummy pointer and make fts_read think that we've just 182 * finished the node before the root(s); set p->fts_info to FTS_INIT 183 * so that everything about the "current" node is ignored. 184 */ 185 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 186 goto mem3; 187 sp->fts_cur->fts_link = root; 188 sp->fts_cur->fts_info = FTS_INIT; 189 190 /* 191 * If using chdir(2), grab a file descriptor pointing to dot to insure 192 * that we can get back here; this could be avoided for some paths, 193 * but almost certainly not worth the effort. Slashes, symbolic links, 194 * and ".." are all fairly nasty problems. Note, if we can't get the 195 * descriptor we run anyway, just more slowly. 196 */ 197 if (!ISSET(FTS_NOCHDIR)) { 198 if ((sp->fts_rfd = open(".", O_RDONLY, 0)) == -1) 199 SET(FTS_NOCHDIR); 200 else if (fcntl(sp->fts_rfd, F_SETFD, FD_CLOEXEC) == -1) { 201 close(sp->fts_rfd); 202 SET(FTS_NOCHDIR); 203 } 204 } 205 206 if (nitems == 0) 207 fts_free(parent); 208 209 return (sp); 210 211mem3: fts_lfree(root); 212 fts_free(parent); 213mem2: free(sp->fts_path); 214mem1: free(sp); 215 return (NULL); 216} 217 218static void 219fts_load(FTS *sp, FTSENT *p) 220{ 221 size_t len; 222 char *cp; 223 224 _DIAGASSERT(sp != NULL); 225 _DIAGASSERT(p != NULL); 226 227 /* 228 * Load the stream structure for the next traversal. Since we don't 229 * actually enter the directory until after the preorder visit, set 230 * the fts_accpath field specially so the chdir gets done to the right 231 * place and the user can access the first node. From fts_open it's 232 * known that the path will fit. 233 */ 234 len = p->fts_pathlen = p->fts_namelen; 235 memmove(sp->fts_path, p->fts_name, len + 1); 236 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 237 len = strlen(++cp); 238 memmove(p->fts_name, cp, len + 1); 239 p->fts_namelen = len; 240 } 241 p->fts_accpath = p->fts_path = sp->fts_path; 242 sp->fts_dev = p->fts_dev; 243} 244 245int 246fts_close(FTS *sp) 247{ 248 FTSENT *freep, *p; 249 int saved_errno = 0; 250 251 _DIAGASSERT(sp != NULL); 252 253 /* 254 * This still works if we haven't read anything -- the dummy structure 255 * points to the root list, so we step through to the end of the root 256 * list which has a valid parent pointer. 257 */ 258 if (sp->fts_cur) { 259 if (ISSET(FTS_SYMFOLLOW)) 260 (void)close(sp->fts_cur->fts_symfd); 261 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 262 freep = p; 263 p = p->fts_link ? p->fts_link : p->fts_parent; 264 fts_free(freep); 265 } 266 fts_free(p); 267 } 268 269 /* Free up child linked list, sort array, path buffer. */ 270 if (sp->fts_child) 271 fts_lfree(sp->fts_child); 272 if (sp->fts_array) 273 free(sp->fts_array); 274 free(sp->fts_path); 275 276 /* Return to original directory, save errno if necessary. */ 277 if (!ISSET(FTS_NOCHDIR)) { 278 if (fchdir(sp->fts_rfd) == -1) 279 saved_errno = errno; 280 (void)close(sp->fts_rfd); 281 } 282 283 /* Free up the stream pointer. */ 284 free(sp); 285 if (saved_errno) { 286 errno = saved_errno; 287 return -1; 288 } 289 290 return 0; 291} 292 293#if !defined(__FTS_COMPAT_TAILINGSLASH) 294 295/* 296 * Special case of "/" at the end of the path so that slashes aren't 297 * appended which would cause paths to be written as "....//foo". 298 */ 299#define NAPPEND(p) \ 300 (p->fts_path[p->fts_pathlen - 1] == '/' \ 301 ? p->fts_pathlen - 1 : p->fts_pathlen) 302 303#else /* !defined(__FTS_COMPAT_TAILINGSLASH) */ 304 305/* 306 * compatibility with the old behaviour. 307 * 308 * Special case a root of "/" so that slashes aren't appended which would 309 * cause paths to be written as "//foo". 310 */ 311 312#define NAPPEND(p) \ 313 (p->fts_level == FTS_ROOTLEVEL && p->fts_pathlen == 1 && \ 314 p->fts_path[0] == '/' ? 0 : p->fts_pathlen) 315 316#endif /* !defined(__FTS_COMPAT_TAILINGSLASH) */ 317 318FTSENT * 319fts_read(FTS *sp) 320{ 321 FTSENT *p, *tmp; 322 int instr; 323 char *t; 324 int saved_errno; 325 326 _DIAGASSERT(sp != NULL); 327 328 /* If finished or unrecoverable error, return NULL. */ 329 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 330 return (NULL); 331 332 /* Set current node pointer. */ 333 p = sp->fts_cur; 334 335 /* Save and zero out user instructions. */ 336 instr = p->fts_instr; 337 p->fts_instr = FTS_NOINSTR; 338 339 /* Any type of file may be re-visited; re-stat and re-turn. */ 340 if (instr == FTS_AGAIN) { 341 p->fts_info = fts_stat(sp, p, 0); 342 return (p); 343 } 344 345 /* 346 * Following a symlink -- SLNONE test allows application to see 347 * SLNONE and recover. If indirecting through a symlink, have 348 * keep a pointer to current location. If unable to get that 349 * pointer, follow fails. 350 */ 351 if (instr == FTS_FOLLOW && 352 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 353 p->fts_info = fts_stat(sp, p, 1); 354 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 355 if ((p->fts_symfd = open(".", O_RDONLY, 0)) == -1) { 356 p->fts_errno = errno; 357 p->fts_info = FTS_ERR; 358 } else if (fcntl(p->fts_symfd, F_SETFD, FD_CLOEXEC) == -1) { 359 p->fts_errno = errno; 360 p->fts_info = FTS_ERR; 361 close(p->fts_symfd); 362 } else 363 p->fts_flags |= FTS_SYMFOLLOW; 364 } 365 return (p); 366 } 367 368 /* Directory in pre-order. */ 369 if (p->fts_info == FTS_D) { 370 /* If skipped or crossed mount point, do post-order visit. */ 371 if (instr == FTS_SKIP || 372 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) { 373 if (p->fts_flags & FTS_SYMFOLLOW) 374 (void)close(p->fts_symfd); 375 if (sp->fts_child) { 376 fts_lfree(sp->fts_child); 377 sp->fts_child = NULL; 378 } 379 p->fts_info = FTS_DP; 380 return (p); 381 } 382 383 /* Rebuild if only read the names and now traversing. */ 384 if (sp->fts_child && ISSET(FTS_NAMEONLY)) { 385 CLR(FTS_NAMEONLY); 386 fts_lfree(sp->fts_child); 387 sp->fts_child = NULL; 388 } 389 390 /* 391 * Cd to the subdirectory. 392 * 393 * If have already read and now fail to chdir, whack the list 394 * to make the names come out right, and set the parent errno 395 * so the application will eventually get an error condition. 396 * Set the FTS_DONTCHDIR flag so that when we logically change 397 * directories back to the parent we don't do a chdir. 398 * 399 * If haven't read do so. If the read fails, fts_build sets 400 * FTS_STOP or the fts_info field of the node. 401 */ 402 if (sp->fts_child) { 403 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) { 404 p->fts_errno = errno; 405 p->fts_flags |= FTS_DONTCHDIR; 406 for (p = sp->fts_child; p; p = p->fts_link) 407 p->fts_accpath = 408 p->fts_parent->fts_accpath; 409 } 410 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 411 if (ISSET(FTS_STOP)) 412 return (NULL); 413 return (p); 414 } 415 p = sp->fts_child; 416 sp->fts_child = NULL; 417 goto name; 418 } 419 420 /* Move to the next node on this level. */ 421next: tmp = p; 422 if ((p = p->fts_link) != NULL) { 423 fts_free(tmp); 424 425 /* 426 * If reached the top, return to the original directory, and 427 * load the paths for the next root. 428 */ 429 if (p->fts_level == FTS_ROOTLEVEL) { 430 if (FCHDIR(sp, sp->fts_rfd)) { 431 SET(FTS_STOP); 432 return (NULL); 433 } 434 fts_load(sp, p); 435 return (sp->fts_cur = p); 436 } 437 438 /* 439 * User may have called fts_set on the node. If skipped, 440 * ignore. If followed, get a file descriptor so we can 441 * get back if necessary. 442 */ 443 if (p->fts_instr == FTS_SKIP) 444 goto next; 445 if (p->fts_instr == FTS_FOLLOW) { 446 p->fts_info = fts_stat(sp, p, 1); 447 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 448 if ((p->fts_symfd = 449 open(".", O_RDONLY, 0)) == -1) { 450 p->fts_errno = errno; 451 p->fts_info = FTS_ERR; 452 } else if (fcntl(p->fts_symfd, F_SETFD, FD_CLOEXEC) == -1) { 453 p->fts_errno = errno; 454 p->fts_info = FTS_ERR; 455 close(p->fts_symfd); 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, (size_t)(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 fts_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 fts_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{ 523 524 _DIAGASSERT(sp != NULL); 525 _DIAGASSERT(p != NULL); 526 527 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW && 528 instr != FTS_NOINSTR && instr != FTS_SKIP) { 529 errno = EINVAL; 530 return (1); 531 } 532 p->fts_instr = instr; 533 return (0); 534} 535 536FTSENT * 537fts_children(FTS *sp, int instr) 538{ 539 FTSENT *p; 540 int fd; 541 542 _DIAGASSERT(sp != NULL); 543 544 if (instr && instr != FTS_NAMEONLY) { 545 errno = EINVAL; 546 return (NULL); 547 } 548 549 /* Set current node pointer. */ 550 p = sp->fts_cur; 551 552 /* 553 * Errno set to 0 so user can distinguish empty directory from 554 * an error. 555 */ 556 errno = 0; 557 558 /* Fatal errors stop here. */ 559 if (ISSET(FTS_STOP)) 560 return (NULL); 561 562 /* Return logical hierarchy of user's arguments. */ 563 if (p->fts_info == FTS_INIT) 564 return (p->fts_link); 565 566 /* 567 * If not a directory being visited in pre-order, stop here. Could 568 * allow FTS_DNR, assuming the user has fixed the problem, but the 569 * same effect is available with FTS_AGAIN. 570 */ 571 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 572 return (NULL); 573 574 /* Free up any previous child list. */ 575 if (sp->fts_child) 576 fts_lfree(sp->fts_child); 577 578 if (instr == FTS_NAMEONLY) { 579 SET(FTS_NAMEONLY); 580 instr = BNAMES; 581 } else 582 instr = BCHILD; 583 584 /* 585 * If using chdir on a relative path and called BEFORE fts_read does 586 * its chdir to the root of a traversal, we can lose -- we need to 587 * chdir into the subdirectory, and we don't know where the current 588 * directory is, so we can't get back so that the upcoming chdir by 589 * fts_read will work. 590 */ 591 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 592 ISSET(FTS_NOCHDIR)) 593 return (sp->fts_child = fts_build(sp, instr)); 594 595 if ((fd = open(".", O_RDONLY, 0)) == -1) 596 return (sp->fts_child = NULL); 597 sp->fts_child = fts_build(sp, instr); 598 if (fchdir(fd)) { 599 (void)close(fd); 600 return (NULL); 601 } 602 (void)close(fd); 603 return (sp->fts_child); 604} 605 606/* 607 * This is the tricky part -- do not casually change *anything* in here. The 608 * idea is to build the linked list of entries that are used by fts_children 609 * and fts_read. There are lots of special cases. 610 * 611 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 612 * set and it's a physical walk (so that symbolic links can't be directories), 613 * we can do things quickly. First, if it's a 4.4BSD file system, the type 614 * of the file is in the directory entry. Otherwise, we assume that the number 615 * of subdirectories in a node is equal to the number of links to the parent. 616 * The former skips all stat calls. The latter skips stat calls in any leaf 617 * directories and for any files after the subdirectories in the directory have 618 * been found, cutting the stat calls by about 2/3. 619 */ 620static FTSENT * 621fts_build(FTS *sp, int type) 622{ 623 struct dirent *dp; 624 FTSENT *p, *head; 625 size_t nitems; 626 FTSENT *cur, *tail; 627 DIR *dirp; 628 void *oldaddr; 629 size_t dnamlen; 630 int cderrno, descend, len, level, nlinks, saved_errno, nostat, doadjust; 631 size_t maxlen; 632#ifdef FTS_WHITEOUT 633 int oflag; 634#endif 635 char *cp = NULL; /* pacify gcc */ 636 637 _DIAGASSERT(sp != NULL); 638 639 /* Set current node pointer. */ 640 cur = sp->fts_cur; 641 642 /* 643 * Open the directory for reading. If this fails, we're done. 644 * If being called from fts_read, set the fts_info field. 645 */ 646#ifdef FTS_WHITEOUT 647 if (ISSET(FTS_WHITEOUT)) 648 oflag = DTF_NODUP|DTF_REWIND; 649 else 650 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND; 651#else 652#define __opendir2(path, flag) opendir(path) 653#endif 654 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 655 if (type == BREAD) { 656 cur->fts_info = FTS_DNR; 657 cur->fts_errno = errno; 658 } 659 return (NULL); 660 } 661 662 /* 663 * Nlinks is the number of possible entries of type directory in the 664 * directory if we're cheating on stat calls, 0 if we're not doing 665 * any stat calls at all, -1 if we're doing stats on everything. 666 */ 667 if (type == BNAMES) { 668 nlinks = 0; 669 nostat = 1; 670 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) { 671 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 672 nostat = 1; 673 } else { 674 nlinks = -1; 675 nostat = 0; 676 } 677 678#ifdef notdef 679 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 680 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 681 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 682#endif 683 /* 684 * If we're going to need to stat anything or we want to descend 685 * and stay in the directory, chdir. If this fails we keep going, 686 * but set a flag so we don't chdir after the post-order visit. 687 * We won't be able to stat anything, but we can still return the 688 * names themselves. Note, that since fts_read won't be able to 689 * chdir into the directory, it will have to return different path 690 * names than before, i.e. "a/b" instead of "b". Since the node 691 * has already been visited in pre-order, have to wait until the 692 * post-order visit to return the error. There is a special case 693 * here, if there was nothing to stat then it's not an error to 694 * not be able to stat. This is all fairly nasty. If a program 695 * needed sorted entries or stat information, they had better be 696 * checking FTS_NS on the returned nodes. 697 */ 698 cderrno = 0; 699 if (nlinks || type == BREAD) { 700 if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) { 701 if (nlinks && type == BREAD) 702 cur->fts_errno = errno; 703 cur->fts_flags |= FTS_DONTCHDIR; 704 descend = 0; 705 cderrno = errno; 706 } else 707 descend = 1; 708 } else 709 descend = 0; 710 711 /* 712 * Figure out the max file name length that can be stored in the 713 * current path -- the inner loop allocates more path as necessary. 714 * We really wouldn't have to do the maxlen calculations here, we 715 * could do them in fts_read before returning the path, but it's a 716 * lot easier here since the length is part of the dirent structure. 717 * 718 * If not changing directories set a pointer so that can just append 719 * each new name into the path. 720 */ 721 len = NAPPEND(cur); 722 if (ISSET(FTS_NOCHDIR)) { 723 cp = sp->fts_path + len; 724 *cp++ = '/'; 725 } 726 len++; 727 maxlen = sp->fts_pathlen - len; 728 729 level = cur->fts_level + 1; 730 731 /* Read the directory, attaching each entry to the `link' pointer. */ 732 doadjust = 0; 733 for (head = tail = NULL, nitems = 0; (dp = readdir(dirp)) != NULL;) { 734 735 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 736 continue; 737 738#if defined(HAVE_STRUCT_DIRENT_D_NAMLEN) 739 dnamlen = dp->d_namlen; 740#else 741 dnamlen = strlen(dp->d_name); 742#endif 743 if ((p = fts_alloc(sp, dp->d_name, dnamlen)) == NULL) 744 goto mem1; 745 if (dnamlen >= maxlen) { /* include space for NUL */ 746 oldaddr = sp->fts_path; 747 if (fts_palloc(sp, dnamlen + len + 1)) { 748 /* 749 * No more memory for path or structures. Save 750 * errno, free up the current structure and the 751 * structures already allocated. 752 */ 753mem1: saved_errno = errno; 754 if (p) 755 fts_free(p); 756 fts_lfree(head); 757 (void)closedir(dirp); 758 errno = saved_errno; 759 cur->fts_info = FTS_ERR; 760 SET(FTS_STOP); 761 return (NULL); 762 } 763 /* Did realloc() change the pointer? */ 764 if (oldaddr != sp->fts_path) { 765 doadjust = 1; 766 if (ISSET(FTS_NOCHDIR)) 767 cp = sp->fts_path + len; 768 } 769 maxlen = sp->fts_pathlen - len; 770 } 771 772#if defined(__FTS_COMPAT_LENGTH) 773 if (len + dnamlen >= USHRT_MAX) { 774 /* 775 * In an FTSENT, fts_pathlen is an unsigned short 776 * so it is possible to wraparound here. 777 * If we do, free up the current structure and the 778 * structures already allocated, then error out 779 * with ENAMETOOLONG. 780 */ 781 fts_free(p); 782 fts_lfree(head); 783 (void)closedir(dirp); 784 cur->fts_info = FTS_ERR; 785 SET(FTS_STOP); 786 errno = ENAMETOOLONG; 787 return (NULL); 788 } 789#endif 790 p->fts_level = level; 791 p->fts_pathlen = len + dnamlen; 792 p->fts_parent = sp->fts_cur; 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, 820 (size_t)(p->fts_namelen + 1)); 821 } else 822 p->fts_accpath = p->fts_name; 823 /* Stat it. */ 824 p->fts_info = fts_stat(sp, p, 0); 825 826 /* Decrement link count if applicable. */ 827 if (nlinks > 0 && (p->fts_info == FTS_D || 828 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 829 --nlinks; 830 } 831 832 /* We walk in directory order so "ls -f" doesn't get upset. */ 833 p->fts_link = NULL; 834 if (head == NULL) 835 head = tail = p; 836 else { 837 tail->fts_link = p; 838 tail = p; 839 } 840 ++nitems; 841 } 842 (void)closedir(dirp); 843 844 /* 845 * If had to realloc the path, adjust the addresses for the rest 846 * of the tree. 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 unsigned short 891fts_stat(FTS *sp, FTSENT *p, int follow) 892{ 893 FTSENT *t; 894 dev_t dev; 895 __fts_ino_t ino; 896 __fts_stat_t *sbp, sb; 897 int saved_errno; 898 899 _DIAGASSERT(sp != NULL); 900 _DIAGASSERT(p != NULL); 901 902 /* If user needs stat info, stat buffer already allocated. */ 903 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 904 905#ifdef FTS_WHITEOUT 906 /* check for whiteout */ 907 if (p->fts_flags & FTS_ISW) { 908 if (sbp != &sb) { 909 memset(sbp, '\0', sizeof (*sbp)); 910 sbp->st_mode = S_IFWHT; 911 } 912 return (FTS_W); 913 } 914#endif 915 916 /* 917 * If doing a logical walk, or application requested FTS_FOLLOW, do 918 * a stat(2). If that fails, check for a non-existent symlink. If 919 * fail, set the errno from the stat call. 920 */ 921 if (ISSET(FTS_LOGICAL) || follow) { 922 if (stat(p->fts_accpath, sbp)) { 923 saved_errno = errno; 924 if (!lstat(p->fts_accpath, sbp)) { 925 errno = 0; 926 return (FTS_SLNONE); 927 } 928 p->fts_errno = saved_errno; 929 goto err; 930 } 931 } else if (lstat(p->fts_accpath, sbp)) { 932 p->fts_errno = errno; 933err: memset(sbp, 0, sizeof(*sbp)); 934 return (FTS_NS); 935 } 936 937 if (S_ISDIR(sbp->st_mode)) { 938 /* 939 * Set the device/inode. Used to find cycles and check for 940 * crossing mount points. Also remember the link count, used 941 * in fts_build to limit the number of stat calls. It is 942 * understood that these fields are only referenced if fts_info 943 * is set to FTS_D. 944 */ 945 dev = p->fts_dev = sbp->st_dev; 946 ino = p->fts_ino = sbp->st_ino; 947 p->fts_nlink = sbp->st_nlink; 948 949 if (ISDOT(p->fts_name)) 950 return (FTS_DOT); 951 952 /* 953 * Cycle detection is done by brute force when the directory 954 * is first encountered. If the tree gets deep enough or the 955 * number of symbolic links to directories is high enough, 956 * something faster might be worthwhile. 957 */ 958 for (t = p->fts_parent; 959 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 960 if (ino == t->fts_ino && dev == t->fts_dev) { 961 p->fts_cycle = t; 962 return (FTS_DC); 963 } 964 return (FTS_D); 965 } 966 if (S_ISLNK(sbp->st_mode)) 967 return (FTS_SL); 968 if (S_ISREG(sbp->st_mode)) 969 return (FTS_F); 970 return (FTS_DEFAULT); 971} 972 973static FTSENT * 974fts_sort(FTS *sp, FTSENT *head, size_t nitems) 975{ 976 FTSENT **ap, *p; 977 978 _DIAGASSERT(sp != NULL); 979 _DIAGASSERT(head != NULL); 980 981 /* 982 * Construct an array of pointers to the structures and call qsort(3). 983 * Reassemble the array in the order returned by qsort. If unable to 984 * sort for memory reasons, return the directory entries in their 985 * current order. Allocate enough space for the current needs plus 986 * 40 so don't realloc one entry at a time. 987 */ 988 if (nitems > sp->fts_nitems) { 989 FTSENT **new; 990 991 new = realloc(sp->fts_array, sizeof(FTSENT *) * (nitems + 40)); 992 if (new == 0) 993 return (head); 994 sp->fts_array = new; 995 sp->fts_nitems = nitems + 40; 996 } 997 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 998 *ap++ = p; 999 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), 1000 (int (*)(const void *, const void *))sp->fts_compar); 1001 for (head = *(ap = sp->fts_array); --nitems; ++ap) 1002 ap[0]->fts_link = ap[1]; 1003 ap[0]->fts_link = NULL; 1004 return (head); 1005} 1006 1007static FTSENT * 1008fts_alloc(FTS *sp, const char *name, size_t namelen) 1009{ 1010 FTSENT *p; 1011 size_t len; 1012 1013 _DIAGASSERT(sp != NULL); 1014 _DIAGASSERT(name != NULL); 1015 1016#if defined(FTS_ALLOC_ALIGNED) 1017 /* 1018 * The file name is a variable length array and no stat structure is 1019 * necessary if the user has set the nostat bit. Allocate the FTSENT 1020 * structure, the file name and the stat structure in one chunk, but 1021 * be careful that the stat structure is reasonably aligned. Since the 1022 * fts_name field is declared to be of size 1, the fts_name pointer is 1023 * namelen + 2 before the first possible address of the stat structure. 1024 */ 1025 len = sizeof(FTSENT) + namelen; 1026 if (!ISSET(FTS_NOSTAT)) 1027 len += sizeof(*(p->fts_statp)) + ALIGNBYTES; 1028 if ((p = malloc(len)) == NULL) 1029 return (NULL); 1030 1031 if (!ISSET(FTS_NOSTAT)) 1032 p->fts_statp = (__fts_stat_t *)ALIGN( 1033 (unsigned long)(p->fts_name + namelen + 2)); 1034#else 1035 if ((p = malloc(sizeof(FTSENT) + namelen)) == NULL) 1036 return (NULL); 1037 1038 if (!ISSET(FTS_NOSTAT)) 1039 if ((p->fts_statp = malloc(sizeof(*(p->fts_statp)))) == NULL) { 1040 free(p); 1041 return (NULL); 1042 } 1043#endif 1044 1045 /* Copy the name plus the trailing NULL. */ 1046 memmove(p->fts_name, name, namelen + 1); 1047 1048 p->fts_namelen = namelen; 1049 p->fts_path = sp->fts_path; 1050 p->fts_errno = 0; 1051 p->fts_flags = 0; 1052 p->fts_instr = FTS_NOINSTR; 1053 p->fts_number = 0; 1054 p->fts_pointer = NULL; 1055 return (p); 1056} 1057 1058static void 1059fts_free(FTSENT *p) 1060{ 1061#if !defined(FTS_ALLOC_ALIGNED) 1062 if (p->fts_statp) 1063 free(p->fts_statp); 1064#endif 1065 free(p); 1066} 1067 1068static void 1069fts_lfree(FTSENT *head) 1070{ 1071 FTSENT *p; 1072 1073 /* XXX: head may be NULL ? */ 1074 1075 /* Free a linked list of structures. */ 1076 while ((p = head) != NULL) { 1077 head = head->fts_link; 1078 fts_free(p); 1079 } 1080} 1081 1082static size_t 1083fts_pow2(size_t x) 1084{ 1085 1086 x--; 1087 x |= x>>1; 1088 x |= x>>2; 1089 x |= x>>4; 1090 x |= x>>8; 1091 x |= x>>16; 1092#if LONG_BIT > 32 1093 x |= x>>32; 1094#endif 1095#if LONG_BIT > 64 1096 x |= x>>64; 1097#endif 1098 x++; 1099 return (x); 1100} 1101 1102/* 1103 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 1104 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 1105 * though the kernel won't resolve them. Round up the new size to a power of 2, 1106 * so we don't realloc the path 2 bytes at a time. 1107 */ 1108static int 1109fts_palloc(FTS *sp, size_t size) 1110{ 1111 char *new; 1112 1113 _DIAGASSERT(sp != NULL); 1114 1115#ifdef __FTS_COMPAT_LENGTH 1116 /* Protect against fts_pathlen overflow. */ 1117 if (size > USHRT_MAX + 1) { 1118 errno = ENAMETOOLONG; 1119 return (1); 1120 } 1121#endif 1122 size = fts_pow2(size); 1123 new = realloc(sp->fts_path, size); 1124 if (new == 0) 1125 return (1); 1126 sp->fts_path = new; 1127 sp->fts_pathlen = size; 1128 return (0); 1129} 1130 1131/* 1132 * When the path is realloc'd, have to fix all of the pointers in structures 1133 * already returned. 1134 */ 1135static void 1136fts_padjust(FTS *sp, FTSENT *head) 1137{ 1138 FTSENT *p; 1139 char *addr; 1140 1141 _DIAGASSERT(sp != NULL); 1142 1143#define ADJUST(p) do { \ 1144 if ((p)->fts_accpath != (p)->fts_name) \ 1145 (p)->fts_accpath = \ 1146 addr + ((p)->fts_accpath - (p)->fts_path); \ 1147 (p)->fts_path = addr; \ 1148} while (/*CONSTCOND*/0) 1149 1150 addr = sp->fts_path; 1151 1152 /* Adjust the current set of children. */ 1153 for (p = sp->fts_child; p; p = p->fts_link) 1154 ADJUST(p); 1155 1156 /* Adjust the rest of the tree, including the current level. */ 1157 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) { 1158 ADJUST(p); 1159 p = p->fts_link ? p->fts_link : p->fts_parent; 1160 } 1161} 1162 1163static size_t 1164fts_maxarglen(char * const *argv) 1165{ 1166 size_t len, max; 1167 1168 _DIAGASSERT(argv != NULL); 1169 1170 for (max = 0; *argv; ++argv) 1171 if ((len = strlen(*argv)) > max) 1172 max = len; 1173 return (max + 1); 1174} 1175 1176/* 1177 * Change to dir specified by fd or p->fts_accpath without getting 1178 * tricked by someone changing the world out from underneath us. 1179 * Assumes p->fts_dev and p->fts_ino are filled in. 1180 */ 1181static int 1182fts_safe_changedir(const FTS *sp, const FTSENT *p, int fd, const char *path) 1183{ 1184 int oldfd = fd, ret = -1; 1185 __fts_stat_t sb; 1186 1187 if (ISSET(FTS_NOCHDIR)) 1188 return 0; 1189 1190 if (oldfd < 0 && (fd = open(path, O_RDONLY)) == -1) 1191 return -1; 1192 1193 if (fstat(fd, &sb) == -1) 1194 goto bail; 1195 1196 if (sb.st_ino != p->fts_ino || sb.st_dev != p->fts_dev) { 1197 errno = ENOENT; 1198 goto bail; 1199 } 1200 1201 ret = fchdir(fd); 1202 1203bail: 1204 if (oldfd < 0) { 1205 int save_errno = errno; 1206 (void)close(fd); 1207 errno = save_errno; 1208 } 1209 return ret; 1210} 1211