fts.c revision 1.31
1/* $NetBSD: fts.c,v 1.31 2006/03/30 01:23:50 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 1.31 2006/03/30 01:23:50 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 if (nitems == 0) 200 free(parent); 201 202 return (sp); 203 204mem3: fts_lfree(root); 205 free(parent); 206mem2: free(sp->fts_path); 207mem1: free(sp); 208 return (NULL); 209} 210 211static void 212fts_load(FTS *sp, FTSENT *p) 213{ 214 size_t len; 215 char *cp; 216 217 _DIAGASSERT(sp != NULL); 218 _DIAGASSERT(p != NULL); 219 220 /* 221 * Load the stream structure for the next traversal. Since we don't 222 * actually enter the directory until after the preorder visit, set 223 * the fts_accpath field specially so the chdir gets done to the right 224 * place and the user can access the first node. From fts_open it's 225 * known that the path will fit. 226 */ 227 len = p->fts_pathlen = p->fts_namelen; 228 memmove(sp->fts_path, p->fts_name, len + 1); 229 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 230 len = strlen(++cp); 231 memmove(p->fts_name, cp, len + 1); 232 p->fts_namelen = len; 233 } 234 p->fts_accpath = p->fts_path = sp->fts_path; 235 sp->fts_dev = p->fts_dev; 236} 237 238int 239fts_close(FTS *sp) 240{ 241 FTSENT *freep, *p; 242 int saved_errno = 0; 243 244 _DIAGASSERT(sp != NULL); 245 246 /* 247 * This still works if we haven't read anything -- the dummy structure 248 * points to the root list, so we step through to the end of the root 249 * list which has a valid parent pointer. 250 */ 251 if (sp->fts_cur) { 252 if (ISSET(FTS_SYMFOLLOW)) 253 (void)close(sp->fts_cur->fts_symfd); 254 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 255 freep = p; 256 p = p->fts_link ? p->fts_link : p->fts_parent; 257 free(freep); 258 } 259 free(p); 260 } 261 262 /* Free up child linked list, sort array, path buffer. */ 263 if (sp->fts_child) 264 fts_lfree(sp->fts_child); 265 if (sp->fts_array) 266 free(sp->fts_array); 267 free(sp->fts_path); 268 269 /* Return to original directory, save errno if necessary. */ 270 if (!ISSET(FTS_NOCHDIR)) { 271 if (fchdir(sp->fts_rfd) == -1) 272 saved_errno = errno; 273 (void)close(sp->fts_rfd); 274 } 275 276 /* Free up the stream pointer. */ 277 free(sp); 278 if (saved_errno) { 279 errno = saved_errno; 280 return -1; 281 } 282 283 return 0; 284} 285 286#if !defined(__FTS_COMPAT_TAILINGSLASH) 287 288/* 289 * Special case of "/" at the end of the path so that slashes aren't 290 * appended which would cause paths to be written as "....//foo". 291 */ 292#define NAPPEND(p) \ 293 (p->fts_path[p->fts_pathlen - 1] == '/' \ 294 ? p->fts_pathlen - 1 : p->fts_pathlen) 295 296#else /* !defined(__FTS_COMPAT_TAILINGSLASH) */ 297 298/* 299 * compatibility with the old behaviour. 300 * 301 * Special case a root of "/" so that slashes aren't appended which would 302 * cause paths to be written as "//foo". 303 */ 304 305#define NAPPEND(p) \ 306 (p->fts_level == FTS_ROOTLEVEL && p->fts_pathlen == 1 && \ 307 p->fts_path[0] == '/' ? 0 : p->fts_pathlen) 308 309#endif /* !defined(__FTS_COMPAT_TAILINGSLASH) */ 310 311FTSENT * 312fts_read(FTS *sp) 313{ 314 FTSENT *p, *tmp; 315 int instr; 316 char *t; 317 int saved_errno; 318 319 _DIAGASSERT(sp != NULL); 320 321 /* If finished or unrecoverable error, return NULL. */ 322 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 323 return (NULL); 324 325 /* Set current node pointer. */ 326 p = sp->fts_cur; 327 328 /* Save and zero out user instructions. */ 329 instr = p->fts_instr; 330 p->fts_instr = FTS_NOINSTR; 331 332 /* Any type of file may be re-visited; re-stat and re-turn. */ 333 if (instr == FTS_AGAIN) { 334 p->fts_info = fts_stat(sp, p, 0); 335 return (p); 336 } 337 338 /* 339 * Following a symlink -- SLNONE test allows application to see 340 * SLNONE and recover. If indirecting through a symlink, have 341 * keep a pointer to current location. If unable to get that 342 * pointer, follow fails. 343 */ 344 if (instr == FTS_FOLLOW && 345 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 346 p->fts_info = fts_stat(sp, p, 1); 347 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 348 if ((p->fts_symfd = open(".", O_RDONLY, 0)) == -1) { 349 p->fts_errno = errno; 350 p->fts_info = FTS_ERR; 351 } else if (fcntl(p->fts_symfd, F_SETFD, FD_CLOEXEC) == -1) { 352 p->fts_errno = errno; 353 p->fts_info = FTS_ERR; 354 close(p->fts_symfd); 355 } else 356 p->fts_flags |= FTS_SYMFOLLOW; 357 } 358 return (p); 359 } 360 361 /* Directory in pre-order. */ 362 if (p->fts_info == FTS_D) { 363 /* If skipped or crossed mount point, do post-order visit. */ 364 if (instr == FTS_SKIP || 365 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) { 366 if (p->fts_flags & FTS_SYMFOLLOW) 367 (void)close(p->fts_symfd); 368 if (sp->fts_child) { 369 fts_lfree(sp->fts_child); 370 sp->fts_child = NULL; 371 } 372 p->fts_info = FTS_DP; 373 return (p); 374 } 375 376 /* Rebuild if only read the names and now traversing. */ 377 if (sp->fts_child && ISSET(FTS_NAMEONLY)) { 378 CLR(FTS_NAMEONLY); 379 fts_lfree(sp->fts_child); 380 sp->fts_child = NULL; 381 } 382 383 /* 384 * Cd to the subdirectory. 385 * 386 * If have already read and now fail to chdir, whack the list 387 * to make the names come out right, and set the parent errno 388 * so the application will eventually get an error condition. 389 * Set the FTS_DONTCHDIR flag so that when we logically change 390 * directories back to the parent we don't do a chdir. 391 * 392 * If haven't read do so. If the read fails, fts_build sets 393 * FTS_STOP or the fts_info field of the node. 394 */ 395 if (sp->fts_child) { 396 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) { 397 p->fts_errno = errno; 398 p->fts_flags |= FTS_DONTCHDIR; 399 for (p = sp->fts_child; p; p = p->fts_link) 400 p->fts_accpath = 401 p->fts_parent->fts_accpath; 402 } 403 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 404 if (ISSET(FTS_STOP)) 405 return (NULL); 406 return (p); 407 } 408 p = sp->fts_child; 409 sp->fts_child = NULL; 410 goto name; 411 } 412 413 /* Move to the next node on this level. */ 414next: tmp = p; 415 if ((p = p->fts_link) != NULL) { 416 free(tmp); 417 418 /* 419 * If reached the top, return to the original directory, and 420 * load the paths for the next root. 421 */ 422 if (p->fts_level == FTS_ROOTLEVEL) { 423 if (FCHDIR(sp, sp->fts_rfd)) { 424 SET(FTS_STOP); 425 return (NULL); 426 } 427 fts_load(sp, p); 428 return (sp->fts_cur = p); 429 } 430 431 /* 432 * User may have called fts_set on the node. If skipped, 433 * ignore. If followed, get a file descriptor so we can 434 * get back if necessary. 435 */ 436 if (p->fts_instr == FTS_SKIP) 437 goto next; 438 if (p->fts_instr == FTS_FOLLOW) { 439 p->fts_info = fts_stat(sp, p, 1); 440 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 441 if ((p->fts_symfd = 442 open(".", O_RDONLY, 0)) == -1) { 443 p->fts_errno = errno; 444 p->fts_info = FTS_ERR; 445 } else if (fcntl(p->fts_symfd, F_SETFD, FD_CLOEXEC) == -1) { 446 p->fts_errno = errno; 447 p->fts_info = FTS_ERR; 448 close(p->fts_symfd); 449 } else 450 p->fts_flags |= FTS_SYMFOLLOW; 451 } 452 p->fts_instr = FTS_NOINSTR; 453 } 454 455name: t = sp->fts_path + NAPPEND(p->fts_parent); 456 *t++ = '/'; 457 memmove(t, p->fts_name, (size_t)(p->fts_namelen + 1)); 458 return (sp->fts_cur = p); 459 } 460 461 /* Move up to the parent node. */ 462 p = tmp->fts_parent; 463 free(tmp); 464 465 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 466 /* 467 * Done; free everything up and set errno to 0 so the user 468 * can distinguish between error and EOF. 469 */ 470 free(p); 471 errno = 0; 472 return (sp->fts_cur = NULL); 473 } 474 475 /* Nul terminate the pathname. */ 476 sp->fts_path[p->fts_pathlen] = '\0'; 477 478 /* 479 * Return to the parent directory. If at a root node or came through 480 * a symlink, go back through the file descriptor. Otherwise, cd up 481 * one directory. 482 */ 483 if (p->fts_level == FTS_ROOTLEVEL) { 484 if (FCHDIR(sp, sp->fts_rfd)) { 485 SET(FTS_STOP); 486 return (NULL); 487 } 488 } else if (p->fts_flags & FTS_SYMFOLLOW) { 489 if (FCHDIR(sp, p->fts_symfd)) { 490 saved_errno = errno; 491 (void)close(p->fts_symfd); 492 errno = saved_errno; 493 SET(FTS_STOP); 494 return (NULL); 495 } 496 (void)close(p->fts_symfd); 497 } else if (!(p->fts_flags & FTS_DONTCHDIR) && 498 fts_safe_changedir(sp, p->fts_parent, -1, "..")) { 499 SET(FTS_STOP); 500 return (NULL); 501 } 502 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 503 return (sp->fts_cur = p); 504} 505 506/* 507 * Fts_set takes the stream as an argument although it's not used in this 508 * implementation; it would be necessary if anyone wanted to add global 509 * semantics to fts using fts_set. An error return is allowed for similar 510 * reasons. 511 */ 512/* ARGSUSED */ 513int 514fts_set(FTS *sp, FTSENT *p, int instr) 515{ 516 517 _DIAGASSERT(sp != NULL); 518 _DIAGASSERT(p != NULL); 519 520 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW && 521 instr != FTS_NOINSTR && instr != FTS_SKIP) { 522 errno = EINVAL; 523 return (1); 524 } 525 p->fts_instr = instr; 526 return (0); 527} 528 529FTSENT * 530fts_children(FTS *sp, int instr) 531{ 532 FTSENT *p; 533 int fd; 534 535 _DIAGASSERT(sp != NULL); 536 537 if (instr && instr != FTS_NAMEONLY) { 538 errno = EINVAL; 539 return (NULL); 540 } 541 542 /* Set current node pointer. */ 543 p = sp->fts_cur; 544 545 /* 546 * Errno set to 0 so user can distinguish empty directory from 547 * an error. 548 */ 549 errno = 0; 550 551 /* Fatal errors stop here. */ 552 if (ISSET(FTS_STOP)) 553 return (NULL); 554 555 /* Return logical hierarchy of user's arguments. */ 556 if (p->fts_info == FTS_INIT) 557 return (p->fts_link); 558 559 /* 560 * If not a directory being visited in pre-order, stop here. Could 561 * allow FTS_DNR, assuming the user has fixed the problem, but the 562 * same effect is available with FTS_AGAIN. 563 */ 564 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 565 return (NULL); 566 567 /* Free up any previous child list. */ 568 if (sp->fts_child) 569 fts_lfree(sp->fts_child); 570 571 if (instr == FTS_NAMEONLY) { 572 SET(FTS_NAMEONLY); 573 instr = BNAMES; 574 } else 575 instr = BCHILD; 576 577 /* 578 * If using chdir on a relative path and called BEFORE fts_read does 579 * its chdir to the root of a traversal, we can lose -- we need to 580 * chdir into the subdirectory, and we don't know where the current 581 * directory is, so we can't get back so that the upcoming chdir by 582 * fts_read will work. 583 */ 584 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 585 ISSET(FTS_NOCHDIR)) 586 return (sp->fts_child = fts_build(sp, instr)); 587 588 if ((fd = open(".", O_RDONLY, 0)) == -1) 589 return (sp->fts_child = NULL); 590 sp->fts_child = fts_build(sp, instr); 591 if (fchdir(fd)) { 592 (void)close(fd); 593 return (NULL); 594 } 595 (void)close(fd); 596 return (sp->fts_child); 597} 598 599/* 600 * This is the tricky part -- do not casually change *anything* in here. The 601 * idea is to build the linked list of entries that are used by fts_children 602 * and fts_read. There are lots of special cases. 603 * 604 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 605 * set and it's a physical walk (so that symbolic links can't be directories), 606 * we can do things quickly. First, if it's a 4.4BSD file system, the type 607 * of the file is in the directory entry. Otherwise, we assume that the number 608 * of subdirectories in a node is equal to the number of links to the parent. 609 * The former skips all stat calls. The latter skips stat calls in any leaf 610 * directories and for any files after the subdirectories in the directory have 611 * been found, cutting the stat calls by about 2/3. 612 */ 613static FTSENT * 614fts_build(FTS *sp, int type) 615{ 616 struct dirent *dp; 617 FTSENT *p, *head; 618 size_t nitems; 619 FTSENT *cur, *tail; 620 DIR *dirp; 621 void *oldaddr; 622 size_t dnamlen; 623 int cderrno, descend, len, level, nlinks, saved_errno, nostat, doadjust; 624 size_t maxlen; 625#ifdef FTS_WHITEOUT 626 int oflag; 627#endif 628 char *cp = NULL; /* pacify gcc */ 629 630 _DIAGASSERT(sp != NULL); 631 632 /* Set current node pointer. */ 633 cur = sp->fts_cur; 634 635 /* 636 * Open the directory for reading. If this fails, we're done. 637 * If being called from fts_read, set the fts_info field. 638 */ 639#ifdef FTS_WHITEOUT 640 if (ISSET(FTS_WHITEOUT)) 641 oflag = DTF_NODUP|DTF_REWIND; 642 else 643 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND; 644#else 645#define __opendir2(path, flag) opendir(path) 646#endif 647 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 648 if (type == BREAD) { 649 cur->fts_info = FTS_DNR; 650 cur->fts_errno = errno; 651 } 652 return (NULL); 653 } 654 655 /* 656 * Nlinks is the number of possible entries of type directory in the 657 * directory if we're cheating on stat calls, 0 if we're not doing 658 * any stat calls at all, -1 if we're doing stats on everything. 659 */ 660 if (type == BNAMES) { 661 nlinks = 0; 662 nostat = 1; 663 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) { 664 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 665 nostat = 1; 666 } else { 667 nlinks = -1; 668 nostat = 0; 669 } 670 671#ifdef notdef 672 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 673 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 674 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 675#endif 676 /* 677 * If we're going to need to stat anything or we want to descend 678 * and stay in the directory, chdir. If this fails we keep going, 679 * but set a flag so we don't chdir after the post-order visit. 680 * We won't be able to stat anything, but we can still return the 681 * names themselves. Note, that since fts_read won't be able to 682 * chdir into the directory, it will have to return different path 683 * names than before, i.e. "a/b" instead of "b". Since the node 684 * has already been visited in pre-order, have to wait until the 685 * post-order visit to return the error. There is a special case 686 * here, if there was nothing to stat then it's not an error to 687 * not be able to stat. This is all fairly nasty. If a program 688 * needed sorted entries or stat information, they had better be 689 * checking FTS_NS on the returned nodes. 690 */ 691 cderrno = 0; 692 if (nlinks || type == BREAD) { 693 if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) { 694 if (nlinks && type == BREAD) 695 cur->fts_errno = errno; 696 cur->fts_flags |= FTS_DONTCHDIR; 697 descend = 0; 698 cderrno = errno; 699 } else 700 descend = 1; 701 } else 702 descend = 0; 703 704 /* 705 * Figure out the max file name length that can be stored in the 706 * current path -- the inner loop allocates more path as necessary. 707 * We really wouldn't have to do the maxlen calculations here, we 708 * could do them in fts_read before returning the path, but it's a 709 * lot easier here since the length is part of the dirent structure. 710 * 711 * If not changing directories set a pointer so that can just append 712 * each new name into the path. 713 */ 714 len = NAPPEND(cur); 715 if (ISSET(FTS_NOCHDIR)) { 716 cp = sp->fts_path + len; 717 *cp++ = '/'; 718 } 719 len++; 720 maxlen = sp->fts_pathlen - len; 721 722 level = cur->fts_level + 1; 723 724 /* Read the directory, attaching each entry to the `link' pointer. */ 725 doadjust = 0; 726 for (head = tail = NULL, nitems = 0; (dp = readdir(dirp)) != NULL;) { 727 728 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 729 continue; 730 731#if HAVE_STRUCT_DIRENT_D_NAMLEN 732 dnamlen = dp->d_namlen; 733#else 734 dnamlen = strlen(dp->d_name); 735#endif 736 if ((p = fts_alloc(sp, dp->d_name, dnamlen)) == NULL) 737 goto mem1; 738 if (dnamlen >= maxlen) { /* include space for NUL */ 739 oldaddr = sp->fts_path; 740 if (fts_palloc(sp, dnamlen + len + 1)) { 741 /* 742 * No more memory for path or structures. Save 743 * errno, free up the current structure and the 744 * structures already allocated. 745 */ 746mem1: saved_errno = errno; 747 if (p) 748 free(p); 749 fts_lfree(head); 750 (void)closedir(dirp); 751 errno = saved_errno; 752 cur->fts_info = FTS_ERR; 753 SET(FTS_STOP); 754 return (NULL); 755 } 756 /* Did realloc() change the pointer? */ 757 if (oldaddr != sp->fts_path) { 758 doadjust = 1; 759 if (ISSET(FTS_NOCHDIR)) 760 cp = sp->fts_path + len; 761 } 762 maxlen = sp->fts_pathlen - len; 763 } 764 765#if defined(__FTS_COMPAT_LENGTH) 766 if (len + dnamlen >= USHRT_MAX) { 767 /* 768 * In an FTSENT, fts_pathlen is a u_short so it is 769 * possible to wraparound here. If we do, free up 770 * the current structure and the structures already 771 * allocated, then error out with ENAMETOOLONG. 772 */ 773 free(p); 774 fts_lfree(head); 775 (void)closedir(dirp); 776 cur->fts_info = FTS_ERR; 777 SET(FTS_STOP); 778 errno = ENAMETOOLONG; 779 return (NULL); 780 } 781#endif 782 p->fts_level = level; 783 p->fts_pathlen = len + dnamlen; 784 p->fts_parent = sp->fts_cur; 785 786#ifdef FTS_WHITEOUT 787 if (dp->d_type == DT_WHT) 788 p->fts_flags |= FTS_ISW; 789#endif 790 791 if (cderrno) { 792 if (nlinks) { 793 p->fts_info = FTS_NS; 794 p->fts_errno = cderrno; 795 } else 796 p->fts_info = FTS_NSOK; 797 p->fts_accpath = cur->fts_accpath; 798 } else if (nlinks == 0 799#ifdef DT_DIR 800 || (nostat && 801 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN) 802#endif 803 ) { 804 p->fts_accpath = 805 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 806 p->fts_info = FTS_NSOK; 807 } else { 808 /* Build a file name for fts_stat to stat. */ 809 if (ISSET(FTS_NOCHDIR)) { 810 p->fts_accpath = p->fts_path; 811 memmove(cp, p->fts_name, 812 (size_t)(p->fts_namelen + 1)); 813 } else 814 p->fts_accpath = p->fts_name; 815 /* Stat it. */ 816 p->fts_info = fts_stat(sp, p, 0); 817 818 /* Decrement link count if applicable. */ 819 if (nlinks > 0 && (p->fts_info == FTS_D || 820 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 821 --nlinks; 822 } 823 824 /* We walk in directory order so "ls -f" doesn't get upset. */ 825 p->fts_link = NULL; 826 if (head == NULL) 827 head = tail = p; 828 else { 829 tail->fts_link = p; 830 tail = p; 831 } 832 ++nitems; 833 } 834 (void)closedir(dirp); 835 836 /* 837 * If had to realloc the path, adjust the addresses for the rest 838 * of the tree. 839 */ 840 if (doadjust) 841 fts_padjust(sp, head); 842 843 /* 844 * If not changing directories, reset the path back to original 845 * state. 846 */ 847 if (ISSET(FTS_NOCHDIR)) { 848 if (len == sp->fts_pathlen || nitems == 0) 849 --cp; 850 *cp = '\0'; 851 } 852 853 /* 854 * If descended after called from fts_children or after called from 855 * fts_read and nothing found, get back. At the root level we use 856 * the saved fd; if one of fts_open()'s arguments is a relative path 857 * to an empty directory, we wind up here with no other way back. If 858 * can't get back, we're done. 859 */ 860 if (descend && (type == BCHILD || !nitems) && 861 (cur->fts_level == FTS_ROOTLEVEL ? 862 FCHDIR(sp, sp->fts_rfd) : 863 fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) { 864 cur->fts_info = FTS_ERR; 865 SET(FTS_STOP); 866 return (NULL); 867 } 868 869 /* If didn't find anything, return NULL. */ 870 if (!nitems) { 871 if (type == BREAD) 872 cur->fts_info = FTS_DP; 873 return (NULL); 874 } 875 876 /* Sort the entries. */ 877 if (sp->fts_compar && nitems > 1) 878 head = fts_sort(sp, head, nitems); 879 return (head); 880} 881 882static u_short 883fts_stat(FTS *sp, FTSENT *p, int follow) 884{ 885 FTSENT *t; 886 dev_t dev; 887 __fts_ino_t ino; 888 __fts_stat_t *sbp, sb; 889 int saved_errno; 890 891 _DIAGASSERT(sp != NULL); 892 _DIAGASSERT(p != NULL); 893 894 /* If user needs stat info, stat buffer already allocated. */ 895 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 896 897#ifdef FTS_WHITEOUT 898 /* check for whiteout */ 899 if (p->fts_flags & FTS_ISW) { 900 if (sbp != &sb) { 901 memset(sbp, '\0', sizeof (*sbp)); 902 sbp->st_mode = S_IFWHT; 903 } 904 return (FTS_W); 905 } 906#endif 907 908 /* 909 * If doing a logical walk, or application requested FTS_FOLLOW, do 910 * a stat(2). If that fails, check for a non-existent symlink. If 911 * fail, set the errno from the stat call. 912 */ 913 if (ISSET(FTS_LOGICAL) || follow) { 914 if (stat(p->fts_accpath, sbp)) { 915 saved_errno = errno; 916 if (!lstat(p->fts_accpath, sbp)) { 917 errno = 0; 918 return (FTS_SLNONE); 919 } 920 p->fts_errno = saved_errno; 921 goto err; 922 } 923 } else if (lstat(p->fts_accpath, sbp)) { 924 p->fts_errno = errno; 925err: memset(sbp, 0, sizeof(*sbp)); 926 return (FTS_NS); 927 } 928 929 if (S_ISDIR(sbp->st_mode)) { 930 /* 931 * Set the device/inode. Used to find cycles and check for 932 * crossing mount points. Also remember the link count, used 933 * in fts_build to limit the number of stat calls. It is 934 * understood that these fields are only referenced if fts_info 935 * is set to FTS_D. 936 */ 937 dev = p->fts_dev = sbp->st_dev; 938 ino = p->fts_ino = sbp->st_ino; 939 p->fts_nlink = sbp->st_nlink; 940 941 if (ISDOT(p->fts_name)) 942 return (FTS_DOT); 943 944 /* 945 * Cycle detection is done by brute force when the directory 946 * is first encountered. If the tree gets deep enough or the 947 * number of symbolic links to directories is high enough, 948 * something faster might be worthwhile. 949 */ 950 for (t = p->fts_parent; 951 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 952 if (ino == t->fts_ino && dev == t->fts_dev) { 953 p->fts_cycle = t; 954 return (FTS_DC); 955 } 956 return (FTS_D); 957 } 958 if (S_ISLNK(sbp->st_mode)) 959 return (FTS_SL); 960 if (S_ISREG(sbp->st_mode)) 961 return (FTS_F); 962 return (FTS_DEFAULT); 963} 964 965static FTSENT * 966fts_sort(FTS *sp, FTSENT *head, size_t nitems) 967{ 968 FTSENT **ap, *p; 969 970 _DIAGASSERT(sp != NULL); 971 _DIAGASSERT(head != NULL); 972 973 /* 974 * Construct an array of pointers to the structures and call qsort(3). 975 * Reassemble the array in the order returned by qsort. If unable to 976 * sort for memory reasons, return the directory entries in their 977 * current order. Allocate enough space for the current needs plus 978 * 40 so don't realloc one entry at a time. 979 */ 980 if (nitems > sp->fts_nitems) { 981 FTSENT **new; 982 983 new = realloc(sp->fts_array, sizeof(FTSENT *) * (nitems + 40)); 984 if (new == 0) 985 return (head); 986 sp->fts_array = new; 987 sp->fts_nitems = nitems + 40; 988 } 989 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 990 *ap++ = p; 991 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), 992 (int (*)(const void *, const void *))sp->fts_compar); 993 for (head = *(ap = sp->fts_array); --nitems; ++ap) 994 ap[0]->fts_link = ap[1]; 995 ap[0]->fts_link = NULL; 996 return (head); 997} 998 999static FTSENT * 1000fts_alloc(FTS *sp, const char *name, size_t namelen) 1001{ 1002 FTSENT *p; 1003 size_t len; 1004 1005 _DIAGASSERT(sp != NULL); 1006 _DIAGASSERT(name != NULL); 1007 1008#if defined(ALIGNBYTES) && defined(ALIGN) 1009 /* 1010 * The file name is a variable length array and no stat structure is 1011 * necessary if the user has set the nostat bit. Allocate the FTSENT 1012 * structure, the file name and the stat structure in one chunk, but 1013 * be careful that the stat structure is reasonably aligned. Since the 1014 * fts_name field is declared to be of size 1, the fts_name pointer is 1015 * namelen + 2 before the first possible address of the stat structure. 1016 */ 1017 len = sizeof(FTSENT) + namelen; 1018 if (!ISSET(FTS_NOSTAT)) 1019 len += sizeof(*(p->fts_statp)) + ALIGNBYTES; 1020 if ((p = malloc(len)) == NULL) 1021 return (NULL); 1022 1023 if (!ISSET(FTS_NOSTAT)) 1024 p->fts_statp = 1025 (__fts_stat_t *)ALIGN((u_long)(p->fts_name + namelen + 2)); 1026#else 1027 if ((p = malloc(sizeof(FTSENT) + namelen)) == NULL) 1028 return (NULL); 1029 1030 if (!ISSET(FTS_NOSTAT)) 1031 if ((p->fts_statp = malloc(sizeof(*(p->fts_statp)))) == NULL) { 1032 free(p); 1033 return (NULL); 1034 } 1035#endif 1036 1037 /* Copy the name plus the trailing NULL. */ 1038 memmove(p->fts_name, name, namelen + 1); 1039 1040 p->fts_namelen = namelen; 1041 p->fts_path = sp->fts_path; 1042 p->fts_errno = 0; 1043 p->fts_flags = 0; 1044 p->fts_instr = FTS_NOINSTR; 1045 p->fts_number = 0; 1046 p->fts_pointer = NULL; 1047 return (p); 1048} 1049 1050static void 1051fts_lfree(FTSENT *head) 1052{ 1053 FTSENT *p; 1054 1055 /* XXX: head may be NULL ? */ 1056 1057 /* Free a linked list of structures. */ 1058 while ((p = head) != NULL) { 1059 head = head->fts_link; 1060 1061#if !defined(ALIGNBYTES) || !defined(ALIGN) 1062 if (p->fts_statp) 1063 free(p->fts_statp); 1064#endif 1065 free(p); 1066 } 1067} 1068 1069static size_t 1070fts_pow2(size_t x) 1071{ 1072 1073 x--; 1074 x |= x>>1; 1075 x |= x>>2; 1076 x |= x>>4; 1077 x |= x>>8; 1078 x |= x>>16; 1079#if LONG_BIT > 32 1080 x |= x>>32; 1081#endif 1082#if LONG_BIT > 64 1083 x |= x>>64; 1084#endif 1085 x++; 1086 return (x); 1087} 1088 1089/* 1090 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 1091 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 1092 * though the kernel won't resolve them. Round up the new size to a power of 2, 1093 * so we don't realloc the path 2 bytes at a time. 1094 */ 1095static int 1096fts_palloc(FTS *sp, size_t size) 1097{ 1098 char *new; 1099 1100 _DIAGASSERT(sp != NULL); 1101 1102#ifdef __FTS_COMPAT_LENGTH 1103 /* Protect against fts_pathlen overflow. */ 1104 if (size > USHRT_MAX + 1) { 1105 errno = ENAMETOOLONG; 1106 return (1); 1107 } 1108#endif 1109 size = fts_pow2(size); 1110 new = realloc(sp->fts_path, size); 1111 if (new == 0) 1112 return (1); 1113 sp->fts_path = new; 1114 sp->fts_pathlen = size; 1115 return (0); 1116} 1117 1118/* 1119 * When the path is realloc'd, have to fix all of the pointers in structures 1120 * already returned. 1121 */ 1122static void 1123fts_padjust(FTS *sp, FTSENT *head) 1124{ 1125 FTSENT *p; 1126 char *addr; 1127 1128 _DIAGASSERT(sp != NULL); 1129 1130#define ADJUST(p) do { \ 1131 if ((p)->fts_accpath != (p)->fts_name) \ 1132 (p)->fts_accpath = \ 1133 addr + ((p)->fts_accpath - (p)->fts_path); \ 1134 (p)->fts_path = addr; \ 1135} while (/*CONSTCOND*/0) 1136 1137 addr = sp->fts_path; 1138 1139 /* Adjust the current set of children. */ 1140 for (p = sp->fts_child; p; p = p->fts_link) 1141 ADJUST(p); 1142 1143 /* Adjust the rest of the tree, including the current level. */ 1144 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) { 1145 ADJUST(p); 1146 p = p->fts_link ? p->fts_link : p->fts_parent; 1147 } 1148} 1149 1150static size_t 1151fts_maxarglen(char * const *argv) 1152{ 1153 size_t len, max; 1154 1155 _DIAGASSERT(argv != NULL); 1156 1157 for (max = 0; *argv; ++argv) 1158 if ((len = strlen(*argv)) > max) 1159 max = len; 1160 return (max + 1); 1161} 1162 1163/* 1164 * Change to dir specified by fd or p->fts_accpath without getting 1165 * tricked by someone changing the world out from underneath us. 1166 * Assumes p->fts_dev and p->fts_ino are filled in. 1167 */ 1168static int 1169fts_safe_changedir(const FTS *sp, const FTSENT *p, int fd, const char *path) 1170{ 1171 int oldfd = fd, ret = -1; 1172 __fts_stat_t sb; 1173 1174 if (ISSET(FTS_NOCHDIR)) 1175 return 0; 1176 1177 if (oldfd < 0 && (fd = open(path, O_RDONLY)) == -1) 1178 return -1; 1179 1180 if (fstat(fd, &sb) == -1) 1181 goto bail; 1182 1183 if (sb.st_ino != p->fts_ino || sb.st_dev != p->fts_dev) { 1184 errno = ENOENT; 1185 goto bail; 1186 } 1187 1188 ret = fchdir(fd); 1189 1190bail: 1191 if (oldfd < 0) { 1192 int save_errno = errno; 1193 (void)close(fd); 1194 errno = save_errno; 1195 } 1196 return ret; 1197} 1198