1 /* $NetBSD: fts.c,v 1.46 2012/09/26 15:33:43 msaitoh 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 39 static char sccsid[] = "@(#)fts.c 8.6 (Berkeley) 8/14/94"; 40 #else 41 __RCSID("$NetBSD: fts.c,v 1.46 2012/09/26 15:33:43 msaitoh 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 62 static FTSENT *fts_alloc(FTS *, const char *, size_t); 63 static FTSENT *fts_build(FTS *, int); 64 static void fts_free(FTSENT *); 65 static void fts_lfree(FTSENT *); 66 static void fts_load(FTS *, FTSENT *); 67 static size_t fts_maxarglen(char * const *); 68 static size_t fts_pow2(size_t); 69 static int fts_palloc(FTS *, size_t); 70 static void fts_padjust(FTS *, FTSENT *); 71 static FTSENT *fts_sort(FTS *, FTSENT *, size_t); 72 static unsigned short fts_stat(FTS *, FTSENT *, int); 73 static 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 #ifndef ftsent_namelen_truncate 83 #define ftsent_namelen_truncate(a) \ 84 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a)) 85 #endif 86 #ifndef ftsent_pathlen_truncate 87 #define ftsent_pathlen_truncate(a) \ 88 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a)) 89 #endif 90 #ifndef fts_pathlen_truncate 91 #define fts_pathlen_truncate(a) \ 92 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a)) 93 #endif 94 #ifndef fts_nitems_truncate 95 #define fts_nitems_truncate(a) \ 96 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a)) 97 #endif 98 99 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2]))) 100 101 #define CLR(opt) (sp->fts_options &= ~(opt)) 102 #define ISSET(opt) (sp->fts_options & (opt)) 103 #define SET(opt) (sp->fts_options |= (opt)) 104 105 #define CHDIR(sp, path) (!ISSET(FTS_NOCHDIR) && chdir(path)) 106 #define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) && fchdir(fd)) 107 108 /* fts_build flags */ 109 #define BCHILD 1 /* fts_children */ 110 #define BNAMES 2 /* fts_children, names only */ 111 #define BREAD 3 /* fts_read */ 112 113 #ifndef DTF_HIDEW 114 #undef FTS_WHITEOUT 115 #endif 116 117 FTS * 118 fts_open(char * const *argv, int options, 119 int (*compar)(const FTSENT **, const FTSENT **)) 120 { 121 FTS *sp; 122 FTSENT *p, *root; 123 size_t nitems; 124 FTSENT *parent, *tmp = NULL; /* pacify gcc */ 125 size_t len; 126 127 _DIAGASSERT(argv != NULL); 128 129 /* Options check. */ 130 if (options & ~FTS_OPTIONMASK) { 131 errno = EINVAL; 132 return (NULL); 133 } 134 135 /* Allocate/initialize the stream */ 136 if ((sp = malloc(sizeof(FTS))) == NULL) 137 return (NULL); 138 memset(sp, 0, sizeof(FTS)); 139 sp->fts_compar = compar; 140 sp->fts_options = options; 141 142 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 143 if (ISSET(FTS_LOGICAL)) 144 SET(FTS_NOCHDIR); 145 146 /* 147 * Start out with 1K of path space, and enough, in any case, 148 * to hold the user's paths. 149 */ 150 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN))) 151 goto mem1; 152 153 /* Allocate/initialize root's parent. */ 154 if ((parent = fts_alloc(sp, "", 0)) == NULL) 155 goto mem2; 156 parent->fts_level = FTS_ROOTPARENTLEVEL; 157 158 /* Allocate/initialize root(s). */ 159 for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) { 160 /* Don't allow zero-length paths. */ 161 if ((len = strlen(*argv)) == 0) { 162 errno = ENOENT; 163 goto mem3; 164 } 165 166 if ((p = fts_alloc(sp, *argv, len)) == NULL) 167 goto mem3; 168 p->fts_level = FTS_ROOTLEVEL; 169 p->fts_parent = parent; 170 p->fts_accpath = p->fts_name; 171 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 172 173 /* Command-line "." and ".." are real directories. */ 174 if (p->fts_info == FTS_DOT) 175 p->fts_info = FTS_D; 176 177 /* 178 * If comparison routine supplied, traverse in sorted 179 * order; otherwise traverse in the order specified. 180 */ 181 if (compar) { 182 p->fts_link = root; 183 root = p; 184 } else { 185 p->fts_link = NULL; 186 if (root == NULL) 187 tmp = root = p; 188 else { 189 tmp->fts_link = p; 190 tmp = p; 191 } 192 } 193 } 194 if (compar && nitems > 1) 195 root = fts_sort(sp, root, nitems); 196 197 /* 198 * Allocate a dummy pointer and make fts_read think that we've just 199 * finished the node before the root(s); set p->fts_info to FTS_INIT 200 * so that everything about the "current" node is ignored. 201 */ 202 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 203 goto mem3; 204 sp->fts_cur->fts_link = root; 205 sp->fts_cur->fts_info = FTS_INIT; 206 207 /* 208 * If using chdir(2), grab a file descriptor pointing to dot to ensure 209 * that we can get back here; this could be avoided for some paths, 210 * but almost certainly not worth the effort. Slashes, symbolic links, 211 * and ".." are all fairly nasty problems. Note, if we can't get the 212 * descriptor we run anyway, just more slowly. 213 */ 214 #ifndef O_CLOEXEC 215 #define O_CLOEXEC 0 216 #endif 217 if (!ISSET(FTS_NOCHDIR)) { 218 if ((sp->fts_rfd = open(".", O_RDONLY | O_CLOEXEC, 0)) == -1) 219 SET(FTS_NOCHDIR); 220 } 221 222 if (nitems == 0) 223 fts_free(parent); 224 225 return (sp); 226 227 mem3: fts_lfree(root); 228 fts_free(parent); 229 mem2: free(sp->fts_path); 230 mem1: free(sp); 231 return (NULL); 232 } 233 234 static void 235 fts_load(FTS *sp, FTSENT *p) 236 { 237 size_t len; 238 char *cp; 239 240 _DIAGASSERT(sp != NULL); 241 _DIAGASSERT(p != NULL); 242 243 /* 244 * Load the stream structure for the next traversal. Since we don't 245 * actually enter the directory until after the preorder visit, set 246 * the fts_accpath field specially so the chdir gets done to the right 247 * place and the user can access the first node. From fts_open it's 248 * known that the path will fit. 249 */ 250 len = p->fts_pathlen = p->fts_namelen; 251 memmove(sp->fts_path, p->fts_name, len + 1); 252 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 253 len = strlen(++cp); 254 memmove(p->fts_name, cp, len + 1); 255 p->fts_namelen = ftsent_namelen_truncate(len); 256 } 257 p->fts_accpath = p->fts_path = sp->fts_path; 258 sp->fts_dev = p->fts_dev; 259 } 260 261 int 262 fts_close(FTS *sp) 263 { 264 FTSENT *freep, *p; 265 int saved_errno = 0; 266 267 _DIAGASSERT(sp != NULL); 268 269 /* 270 * This still works if we haven't read anything -- the dummy structure 271 * points to the root list, so we step through to the end of the root 272 * list which has a valid parent pointer. 273 */ 274 if (sp->fts_cur) { 275 if (sp->fts_cur->fts_flags & FTS_SYMFOLLOW) 276 (void)close(sp->fts_cur->fts_symfd); 277 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 278 freep = p; 279 p = p->fts_link ? p->fts_link : p->fts_parent; 280 fts_free(freep); 281 } 282 fts_free(p); 283 } 284 285 /* Free up child linked list, sort array, path buffer. */ 286 if (sp->fts_child) 287 fts_lfree(sp->fts_child); 288 if (sp->fts_array) 289 free(sp->fts_array); 290 free(sp->fts_path); 291 292 /* Return to original directory, save errno if necessary. */ 293 if (!ISSET(FTS_NOCHDIR)) { 294 if (fchdir(sp->fts_rfd) == -1) 295 saved_errno = errno; 296 (void)close(sp->fts_rfd); 297 } 298 299 /* Free up the stream pointer. */ 300 free(sp); 301 if (saved_errno) { 302 errno = saved_errno; 303 return -1; 304 } 305 306 return 0; 307 } 308 309 #if !defined(__FTS_COMPAT_TAILINGSLASH) 310 311 /* 312 * Special case of "/" at the end of the path so that slashes aren't 313 * appended which would cause paths to be written as "....//foo". 314 */ 315 #define NAPPEND(p) \ 316 (p->fts_path[p->fts_pathlen - 1] == '/' \ 317 ? p->fts_pathlen - 1 : p->fts_pathlen) 318 319 #else /* !defined(__FTS_COMPAT_TAILINGSLASH) */ 320 321 /* 322 * compatibility with the old behaviour. 323 * 324 * Special case a root of "/" so that slashes aren't appended which would 325 * cause paths to be written as "//foo". 326 */ 327 328 #define NAPPEND(p) \ 329 (p->fts_level == FTS_ROOTLEVEL && p->fts_pathlen == 1 && \ 330 p->fts_path[0] == '/' ? 0 : p->fts_pathlen) 331 332 #endif /* !defined(__FTS_COMPAT_TAILINGSLASH) */ 333 334 FTSENT * 335 fts_read(FTS *sp) 336 { 337 FTSENT *p, *tmp; 338 int instr; 339 char *t; 340 int saved_errno; 341 342 _DIAGASSERT(sp != NULL); 343 344 /* If finished or unrecoverable error, return NULL. */ 345 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 346 return (NULL); 347 348 /* Set current node pointer. */ 349 p = sp->fts_cur; 350 351 /* Save and zero out user instructions. */ 352 instr = p->fts_instr; 353 p->fts_instr = FTS_NOINSTR; 354 355 /* Any type of file may be re-visited; re-stat and re-turn. */ 356 if (instr == FTS_AGAIN) { 357 p->fts_info = fts_stat(sp, p, 0); 358 return (p); 359 } 360 361 /* 362 * Following a symlink -- SLNONE test allows application to see 363 * SLNONE and recover. If indirecting through a symlink, have 364 * keep a pointer to current location. If unable to get that 365 * pointer, follow fails. 366 */ 367 if (instr == FTS_FOLLOW && 368 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 369 p->fts_info = fts_stat(sp, p, 1); 370 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 371 if ((p->fts_symfd = open(".", O_RDONLY | O_CLOEXEC, 0)) 372 == -1) { 373 p->fts_errno = errno; 374 p->fts_info = FTS_ERR; 375 } else 376 p->fts_flags |= FTS_SYMFOLLOW; 377 } 378 return (p); 379 } 380 381 /* Directory in pre-order. */ 382 if (p->fts_info == FTS_D) { 383 /* If skipped or crossed mount point, do post-order visit. */ 384 if (instr == FTS_SKIP || 385 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) { 386 if (p->fts_flags & FTS_SYMFOLLOW) 387 (void)close(p->fts_symfd); 388 if (sp->fts_child) { 389 fts_lfree(sp->fts_child); 390 sp->fts_child = NULL; 391 } 392 p->fts_info = FTS_DP; 393 return (p); 394 } 395 396 /* Rebuild if only read the names and now traversing. */ 397 if (sp->fts_child && ISSET(FTS_NAMEONLY)) { 398 CLR(FTS_NAMEONLY); 399 fts_lfree(sp->fts_child); 400 sp->fts_child = NULL; 401 } 402 403 /* 404 * Cd to the subdirectory. 405 * 406 * If have already read and now fail to chdir, whack the list 407 * to make the names come out right, and set the parent errno 408 * so the application will eventually get an error condition. 409 * Set the FTS_DONTCHDIR flag so that when we logically change 410 * directories back to the parent we don't do a chdir. 411 * 412 * If haven't read do so. If the read fails, fts_build sets 413 * FTS_STOP or the fts_info field of the node. 414 */ 415 if (sp->fts_child) { 416 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) { 417 p->fts_errno = errno; 418 p->fts_flags |= FTS_DONTCHDIR; 419 for (p = sp->fts_child; p; p = p->fts_link) 420 p->fts_accpath = 421 p->fts_parent->fts_accpath; 422 } 423 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 424 if (ISSET(FTS_STOP)) 425 return (NULL); 426 return (p); 427 } 428 p = sp->fts_child; 429 sp->fts_child = NULL; 430 goto name; 431 } 432 433 /* Move to the next node on this level. */ 434 next: tmp = p; 435 if ((p = p->fts_link) != NULL) { 436 fts_free(tmp); 437 438 /* 439 * If reached the top, return to the original directory, and 440 * load the paths for the next root. 441 */ 442 if (p->fts_level == FTS_ROOTLEVEL) { 443 if (FCHDIR(sp, sp->fts_rfd)) { 444 SET(FTS_STOP); 445 return (NULL); 446 } 447 fts_load(sp, p); 448 return (sp->fts_cur = p); 449 } 450 451 /* 452 * User may have called fts_set on the node. If skipped, 453 * ignore. If followed, get a file descriptor so we can 454 * get back if necessary. 455 */ 456 if (p->fts_instr == FTS_SKIP) 457 goto next; 458 if (p->fts_instr == FTS_FOLLOW) { 459 p->fts_info = fts_stat(sp, p, 1); 460 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 461 if ((p->fts_symfd = 462 open(".", O_RDONLY | O_CLOEXEC, 0)) == -1) { 463 p->fts_errno = errno; 464 p->fts_info = FTS_ERR; 465 } else 466 p->fts_flags |= FTS_SYMFOLLOW; 467 } 468 p->fts_instr = FTS_NOINSTR; 469 } 470 471 name: t = sp->fts_path + NAPPEND(p->fts_parent); 472 *t++ = '/'; 473 memmove(t, p->fts_name, (size_t)(p->fts_namelen + 1)); 474 return (sp->fts_cur = p); 475 } 476 477 /* Move up to the parent node. */ 478 p = tmp->fts_parent; 479 fts_free(tmp); 480 481 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 482 /* 483 * Done; free everything up and set errno to 0 so the user 484 * can distinguish between error and EOF. 485 */ 486 fts_free(p); 487 errno = 0; 488 return (sp->fts_cur = NULL); 489 } 490 491 /* NUL terminate the pathname. */ 492 sp->fts_path[p->fts_pathlen] = '\0'; 493 494 /* 495 * Return to the parent directory. If at a root node or came through 496 * a symlink, go back through the file descriptor. Otherwise, cd up 497 * one directory. 498 */ 499 if (p->fts_level == FTS_ROOTLEVEL) { 500 if (FCHDIR(sp, sp->fts_rfd)) { 501 SET(FTS_STOP); 502 return (NULL); 503 } 504 } else if (p->fts_flags & FTS_SYMFOLLOW) { 505 if (FCHDIR(sp, p->fts_symfd)) { 506 saved_errno = errno; 507 (void)close(p->fts_symfd); 508 errno = saved_errno; 509 SET(FTS_STOP); 510 return (NULL); 511 } 512 (void)close(p->fts_symfd); 513 } else if (!(p->fts_flags & FTS_DONTCHDIR) && 514 fts_safe_changedir(sp, p->fts_parent, -1, "..")) { 515 SET(FTS_STOP); 516 return (NULL); 517 } 518 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 519 return (sp->fts_cur = p); 520 } 521 522 /* 523 * Fts_set takes the stream as an argument although it's not used in this 524 * implementation; it would be necessary if anyone wanted to add global 525 * semantics to fts using fts_set. An error return is allowed for similar 526 * reasons. 527 */ 528 /* ARGSUSED */ 529 int 530 fts_set(FTS *sp, FTSENT *p, int instr) 531 { 532 533 _DIAGASSERT(sp != NULL); 534 _DIAGASSERT(p != NULL); 535 536 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW && 537 instr != FTS_NOINSTR && instr != FTS_SKIP) { 538 errno = EINVAL; 539 return (1); 540 } 541 p->fts_instr = instr; 542 return (0); 543 } 544 545 FTSENT * 546 fts_children(FTS *sp, int instr) 547 { 548 FTSENT *p; 549 int fd; 550 551 _DIAGASSERT(sp != NULL); 552 553 if (instr && instr != FTS_NAMEONLY) { 554 errno = EINVAL; 555 return (NULL); 556 } 557 558 /* Set current node pointer. */ 559 p = sp->fts_cur; 560 561 /* 562 * Errno set to 0 so user can distinguish empty directory from 563 * an error. 564 */ 565 errno = 0; 566 567 /* Fatal errors stop here. */ 568 if (ISSET(FTS_STOP)) 569 return (NULL); 570 571 /* Return logical hierarchy of user's arguments. */ 572 if (p->fts_info == FTS_INIT) 573 return (p->fts_link); 574 575 /* 576 * If not a directory being visited in pre-order, stop here. Could 577 * allow FTS_DNR, assuming the user has fixed the problem, but the 578 * same effect is available with FTS_AGAIN. 579 */ 580 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 581 return (NULL); 582 583 /* Free up any previous child list. */ 584 if (sp->fts_child) 585 fts_lfree(sp->fts_child); 586 587 if (instr == FTS_NAMEONLY) { 588 SET(FTS_NAMEONLY); 589 instr = BNAMES; 590 } else 591 instr = BCHILD; 592 593 /* 594 * If using chdir on a relative path and called BEFORE fts_read does 595 * its chdir to the root of a traversal, we can lose -- we need to 596 * chdir into the subdirectory, and we don't know where the current 597 * directory is, so we can't get back so that the upcoming chdir by 598 * fts_read will work. 599 */ 600 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 601 ISSET(FTS_NOCHDIR)) 602 return (sp->fts_child = fts_build(sp, instr)); 603 604 if ((fd = open(".", O_RDONLY, 0)) == -1) 605 return (sp->fts_child = NULL); 606 sp->fts_child = fts_build(sp, instr); 607 if (fchdir(fd)) { 608 (void)close(fd); 609 return (NULL); 610 } 611 (void)close(fd); 612 return (sp->fts_child); 613 } 614 615 /* 616 * This is the tricky part -- do not casually change *anything* in here. The 617 * idea is to build the linked list of entries that are used by fts_children 618 * and fts_read. There are lots of special cases. 619 * 620 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 621 * set and it's a physical walk (so that symbolic links can't be directories), 622 * we can do things quickly. First, if it's a 4.4BSD file system, the type 623 * of the file is in the directory entry. Otherwise, we assume that the number 624 * of subdirectories in a node is equal to the number of links to the parent. 625 * The former skips all stat calls. The latter skips stat calls in any leaf 626 * directories and for any files after the subdirectories in the directory have 627 * been found, cutting the stat calls by about 2/3. 628 */ 629 static FTSENT * 630 fts_build(FTS *sp, int type) 631 { 632 struct dirent *dp; 633 FTSENT *p, *head; 634 size_t nitems; 635 FTSENT *cur, *tail; 636 DIR *dirp; 637 void *oldaddr; 638 size_t dnamlen; 639 int cderrno, descend, level, nlinks, saved_errno, nostat, doadjust; 640 size_t len, maxlen; 641 #ifdef FTS_WHITEOUT 642 int oflag; 643 #endif 644 char *cp = NULL; /* pacify gcc */ 645 646 _DIAGASSERT(sp != NULL); 647 648 /* Set current node pointer. */ 649 cur = sp->fts_cur; 650 651 /* 652 * Open the directory for reading. If this fails, we're done. 653 * If being called from fts_read, set the fts_info field. 654 */ 655 #ifdef FTS_WHITEOUT 656 if (ISSET(FTS_WHITEOUT)) 657 oflag = DTF_NODUP|DTF_REWIND; 658 else 659 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND; 660 #else 661 #define __opendir2(path, flag) opendir(path) 662 #endif 663 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 664 if (type == BREAD) { 665 cur->fts_info = FTS_DNR; 666 cur->fts_errno = errno; 667 } 668 return (NULL); 669 } 670 671 /* 672 * Nlinks is the number of possible entries of type directory in the 673 * directory if we're cheating on stat calls, 0 if we're not doing 674 * any stat calls at all, -1 if we're doing stats on everything. 675 */ 676 if (type == BNAMES) { 677 nlinks = 0; 678 nostat = 1; 679 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) { 680 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 681 nostat = 1; 682 } else { 683 nlinks = -1; 684 nostat = 0; 685 } 686 687 #ifdef notdef 688 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 689 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 690 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 691 #endif 692 /* 693 * If we're going to need to stat anything or we want to descend 694 * and stay in the directory, chdir. If this fails we keep going, 695 * but set a flag so we don't chdir after the post-order visit. 696 * We won't be able to stat anything, but we can still return the 697 * names themselves. Note, that since fts_read won't be able to 698 * chdir into the directory, it will have to return different path 699 * names than before, i.e. "a/b" instead of "b". Since the node 700 * has already been visited in pre-order, have to wait until the 701 * post-order visit to return the error. There is a special case 702 * here, if there was nothing to stat then it's not an error to 703 * not be able to stat. This is all fairly nasty. If a program 704 * needed sorted entries or stat information, they had better be 705 * checking FTS_NS on the returned nodes. 706 */ 707 cderrno = 0; 708 if (nlinks || type == BREAD) { 709 if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) { 710 if (nlinks && type == BREAD) 711 cur->fts_errno = errno; 712 cur->fts_flags |= FTS_DONTCHDIR; 713 descend = 0; 714 cderrno = errno; 715 } else 716 descend = 1; 717 } else 718 descend = 0; 719 720 /* 721 * Figure out the max file name length that can be stored in the 722 * current path -- the inner loop allocates more path as necessary. 723 * We really wouldn't have to do the maxlen calculations here, we 724 * could do them in fts_read before returning the path, but it's a 725 * lot easier here since the length is part of the dirent structure. 726 * 727 * If not changing directories set a pointer so that can just append 728 * each new name into the path. 729 */ 730 len = NAPPEND(cur); 731 if (ISSET(FTS_NOCHDIR)) { 732 cp = sp->fts_path + len; 733 *cp++ = '/'; 734 } 735 len++; 736 maxlen = sp->fts_pathlen - len; 737 738 #if defined(__FTS_COMPAT_LEVEL) 739 if (cur->fts_level == SHRT_MAX) { 740 (void)closedir(dirp); 741 cur->fts_info = FTS_ERR; 742 SET(FTS_STOP); 743 errno = ENAMETOOLONG; 744 return (NULL); 745 } 746 #endif 747 748 level = cur->fts_level + 1; 749 750 /* Read the directory, attaching each entry to the `link' pointer. */ 751 doadjust = 0; 752 for (head = tail = NULL, nitems = 0; (dp = readdir(dirp)) != NULL;) { 753 754 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 755 continue; 756 757 #if defined(HAVE_STRUCT_DIRENT_D_NAMLEN) 758 dnamlen = dp->d_namlen; 759 #else 760 dnamlen = strlen(dp->d_name); 761 #endif 762 if ((p = fts_alloc(sp, dp->d_name, dnamlen)) == NULL) 763 goto mem1; 764 if (dnamlen >= maxlen) { /* include space for NUL */ 765 oldaddr = sp->fts_path; 766 if (fts_palloc(sp, dnamlen + len + 1)) { 767 /* 768 * No more memory for path or structures. Save 769 * errno, free up the current structure and the 770 * structures already allocated. 771 */ 772 mem1: saved_errno = errno; 773 if (p) 774 fts_free(p); 775 fts_lfree(head); 776 (void)closedir(dirp); 777 errno = saved_errno; 778 cur->fts_info = FTS_ERR; 779 SET(FTS_STOP); 780 return (NULL); 781 } 782 /* Did realloc() change the pointer? */ 783 if (oldaddr != sp->fts_path) { 784 doadjust = 1; 785 if (ISSET(FTS_NOCHDIR)) 786 cp = sp->fts_path + len; 787 } 788 maxlen = sp->fts_pathlen - len; 789 } 790 791 #if defined(__FTS_COMPAT_LENGTH) 792 if (len + dnamlen >= USHRT_MAX) { 793 /* 794 * In an FTSENT, fts_pathlen is an unsigned short 795 * so it is possible to wraparound here. 796 * If we do, free up the current structure and the 797 * structures already allocated, then error out 798 * with ENAMETOOLONG. 799 */ 800 fts_free(p); 801 fts_lfree(head); 802 (void)closedir(dirp); 803 cur->fts_info = FTS_ERR; 804 SET(FTS_STOP); 805 errno = ENAMETOOLONG; 806 return (NULL); 807 } 808 #endif 809 p->fts_level = level; 810 p->fts_pathlen = ftsent_pathlen_truncate(len + dnamlen); 811 p->fts_parent = sp->fts_cur; 812 813 #ifdef FTS_WHITEOUT 814 if (dp->d_type == DT_WHT) 815 p->fts_flags |= FTS_ISW; 816 #endif 817 818 if (cderrno) { 819 if (nlinks) { 820 p->fts_info = FTS_NS; 821 p->fts_errno = cderrno; 822 } else 823 p->fts_info = FTS_NSOK; 824 p->fts_accpath = cur->fts_accpath; 825 } else if (nlinks == 0 826 #ifdef DT_DIR 827 || (nostat && 828 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN) 829 #endif 830 ) { 831 p->fts_accpath = 832 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 833 p->fts_info = FTS_NSOK; 834 } else { 835 /* Build a file name for fts_stat to stat. */ 836 if (ISSET(FTS_NOCHDIR)) { 837 p->fts_accpath = p->fts_path; 838 memmove(cp, p->fts_name, 839 (size_t)(p->fts_namelen + 1)); 840 } else 841 p->fts_accpath = p->fts_name; 842 /* Stat it. */ 843 p->fts_info = fts_stat(sp, p, 0); 844 845 /* Decrement link count if applicable. */ 846 if (nlinks > 0 && (p->fts_info == FTS_D || 847 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 848 --nlinks; 849 } 850 851 /* We walk in directory order so "ls -f" doesn't get upset. */ 852 p->fts_link = NULL; 853 if (head == NULL) 854 head = tail = p; 855 else { 856 tail->fts_link = p; 857 tail = p; 858 } 859 ++nitems; 860 } 861 (void)closedir(dirp); 862 863 /* 864 * If had to realloc the path, adjust the addresses for the rest 865 * of the tree. 866 */ 867 if (doadjust) 868 fts_padjust(sp, head); 869 870 /* 871 * If not changing directories, reset the path back to original 872 * state. 873 */ 874 if (ISSET(FTS_NOCHDIR)) { 875 if (len == sp->fts_pathlen || nitems == 0) 876 --cp; 877 *cp = '\0'; 878 } 879 880 /* 881 * If descended after called from fts_children or after called from 882 * fts_read and nothing found, get back. At the root level we use 883 * the saved fd; if one of fts_open()'s arguments is a relative path 884 * to an empty directory, we wind up here with no other way back. If 885 * can't get back, we're done. 886 */ 887 if (descend && (type == BCHILD || !nitems) && 888 (cur->fts_level == FTS_ROOTLEVEL ? 889 FCHDIR(sp, sp->fts_rfd) : 890 fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) { 891 cur->fts_info = FTS_ERR; 892 SET(FTS_STOP); 893 return (NULL); 894 } 895 896 /* If didn't find anything, return NULL. */ 897 if (!nitems) { 898 if (type == BREAD) 899 cur->fts_info = FTS_DP; 900 return (NULL); 901 } 902 903 /* Sort the entries. */ 904 if (sp->fts_compar && nitems > 1) 905 head = fts_sort(sp, head, nitems); 906 return (head); 907 } 908 909 static unsigned short 910 fts_stat(FTS *sp, FTSENT *p, int follow) 911 { 912 FTSENT *t; 913 dev_t dev; 914 __fts_ino_t ino; 915 __fts_stat_t *sbp, sb; 916 int saved_errno; 917 918 _DIAGASSERT(sp != NULL); 919 _DIAGASSERT(p != NULL); 920 921 /* If user needs stat info, stat buffer already allocated. */ 922 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 923 924 #ifdef FTS_WHITEOUT 925 /* check for whiteout */ 926 if (p->fts_flags & FTS_ISW) { 927 if (sbp != &sb) { 928 memset(sbp, '\0', sizeof (*sbp)); 929 sbp->st_mode = S_IFWHT; 930 } 931 return (FTS_W); 932 } 933 #endif 934 935 /* 936 * If doing a logical walk, or application requested FTS_FOLLOW, do 937 * a stat(2). If that fails, check for a non-existent symlink. If 938 * fail, set the errno from the stat call. 939 */ 940 if (ISSET(FTS_LOGICAL) || follow) { 941 if (stat(p->fts_accpath, sbp)) { 942 saved_errno = errno; 943 if (!lstat(p->fts_accpath, sbp)) { 944 errno = 0; 945 return (FTS_SLNONE); 946 } 947 p->fts_errno = saved_errno; 948 goto err; 949 } 950 } else if (lstat(p->fts_accpath, sbp)) { 951 p->fts_errno = errno; 952 err: memset(sbp, 0, sizeof(*sbp)); 953 return (FTS_NS); 954 } 955 956 if (S_ISDIR(sbp->st_mode)) { 957 /* 958 * Set the device/inode. Used to find cycles and check for 959 * crossing mount points. Also remember the link count, used 960 * in fts_build to limit the number of stat calls. It is 961 * understood that these fields are only referenced if fts_info 962 * is set to FTS_D. 963 */ 964 dev = p->fts_dev = sbp->st_dev; 965 ino = p->fts_ino = sbp->st_ino; 966 p->fts_nlink = sbp->st_nlink; 967 968 if (ISDOT(p->fts_name)) 969 return (FTS_DOT); 970 971 /* 972 * Cycle detection is done by brute force when the directory 973 * is first encountered. If the tree gets deep enough or the 974 * number of symbolic links to directories is high enough, 975 * something faster might be worthwhile. 976 */ 977 for (t = p->fts_parent; 978 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 979 if (ino == t->fts_ino && dev == t->fts_dev) { 980 p->fts_cycle = t; 981 return (FTS_DC); 982 } 983 return (FTS_D); 984 } 985 if (S_ISLNK(sbp->st_mode)) 986 return (FTS_SL); 987 if (S_ISREG(sbp->st_mode)) 988 return (FTS_F); 989 return (FTS_DEFAULT); 990 } 991 992 static FTSENT * 993 fts_sort(FTS *sp, FTSENT *head, size_t nitems) 994 { 995 FTSENT **ap, *p; 996 997 _DIAGASSERT(sp != NULL); 998 _DIAGASSERT(head != NULL); 999 1000 /* 1001 * Construct an array of pointers to the structures and call qsort(3). 1002 * Reassemble the array in the order returned by qsort. If unable to 1003 * sort for memory reasons, return the directory entries in their 1004 * current order. Allocate enough space for the current needs plus 1005 * 40 so don't realloc one entry at a time. 1006 */ 1007 if (nitems > sp->fts_nitems) { 1008 FTSENT **new; 1009 1010 new = realloc(sp->fts_array, sizeof(FTSENT *) * (nitems + 40)); 1011 if (new == 0) 1012 return (head); 1013 sp->fts_array = new; 1014 sp->fts_nitems = fts_nitems_truncate(nitems + 40); 1015 } 1016 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 1017 *ap++ = p; 1018 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), 1019 (int (*)(const void *, const void *))sp->fts_compar); 1020 for (head = *(ap = sp->fts_array); --nitems; ++ap) 1021 ap[0]->fts_link = ap[1]; 1022 ap[0]->fts_link = NULL; 1023 return (head); 1024 } 1025 1026 static FTSENT * 1027 fts_alloc(FTS *sp, const char *name, size_t namelen) 1028 { 1029 FTSENT *p; 1030 #if defined(FTS_ALLOC_ALIGNED) 1031 size_t len; 1032 #endif 1033 1034 _DIAGASSERT(sp != NULL); 1035 _DIAGASSERT(name != NULL); 1036 1037 #if defined(FTS_ALLOC_ALIGNED) 1038 /* 1039 * The file name is a variable length array and no stat structure is 1040 * necessary if the user has set the nostat bit. Allocate the FTSENT 1041 * structure, the file name and the stat structure in one chunk, but 1042 * be careful that the stat structure is reasonably aligned. Since the 1043 * fts_name field is declared to be of size 1, the fts_name pointer is 1044 * namelen + 2 before the first possible address of the stat structure. 1045 */ 1046 len = sizeof(FTSENT) + namelen; 1047 if (!ISSET(FTS_NOSTAT)) 1048 len += sizeof(*(p->fts_statp)) + ALIGNBYTES; 1049 if ((p = malloc(len)) == NULL) 1050 return (NULL); 1051 1052 if (!ISSET(FTS_NOSTAT)) 1053 p->fts_statp = (__fts_stat_t *)ALIGN( 1054 (unsigned long)(p->fts_name + namelen + 2)); 1055 #else 1056 if ((p = malloc(sizeof(FTSENT) + namelen)) == NULL) 1057 return (NULL); 1058 1059 if (!ISSET(FTS_NOSTAT)) 1060 if ((p->fts_statp = malloc(sizeof(*(p->fts_statp)))) == NULL) { 1061 free(p); 1062 return (NULL); 1063 } 1064 #endif 1065 1066 if (ISSET(FTS_NOSTAT)) 1067 p->fts_statp = NULL; 1068 1069 /* Copy the name plus the trailing NULL. */ 1070 memmove(p->fts_name, name, namelen + 1); 1071 1072 p->fts_namelen = ftsent_namelen_truncate(namelen); 1073 p->fts_path = sp->fts_path; 1074 p->fts_errno = 0; 1075 p->fts_flags = 0; 1076 p->fts_instr = FTS_NOINSTR; 1077 p->fts_number = 0; 1078 p->fts_pointer = NULL; 1079 return (p); 1080 } 1081 1082 static void 1083 fts_free(FTSENT *p) 1084 { 1085 #if !defined(FTS_ALLOC_ALIGNED) 1086 if (p->fts_statp) 1087 free(p->fts_statp); 1088 #endif 1089 free(p); 1090 } 1091 1092 static void 1093 fts_lfree(FTSENT *head) 1094 { 1095 FTSENT *p; 1096 1097 /* XXX: head may be NULL ? */ 1098 1099 /* Free a linked list of structures. */ 1100 while ((p = head) != NULL) { 1101 head = head->fts_link; 1102 fts_free(p); 1103 } 1104 } 1105 1106 static size_t 1107 fts_pow2(size_t x) 1108 { 1109 1110 x--; 1111 x |= x>>1; 1112 x |= x>>2; 1113 x |= x>>4; 1114 x |= x>>8; 1115 x |= x>>16; 1116 #if LONG_BIT > 32 1117 x |= x>>32; 1118 #endif 1119 #if LONG_BIT > 64 1120 x |= x>>64; 1121 #endif 1122 x++; 1123 return (x); 1124 } 1125 1126 /* 1127 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 1128 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 1129 * though the kernel won't resolve them. Round up the new size to a power of 2, 1130 * so we don't realloc the path 2 bytes at a time. 1131 */ 1132 static int 1133 fts_palloc(FTS *sp, size_t size) 1134 { 1135 char *new; 1136 1137 _DIAGASSERT(sp != NULL); 1138 1139 #ifdef __FTS_COMPAT_LENGTH 1140 /* Protect against fts_pathlen overflow. */ 1141 if (size > USHRT_MAX + 1) { 1142 errno = ENAMETOOLONG; 1143 return (1); 1144 } 1145 #endif 1146 size = fts_pow2(size); 1147 new = realloc(sp->fts_path, size); 1148 if (new == 0) 1149 return (1); 1150 sp->fts_path = new; 1151 sp->fts_pathlen = fts_pathlen_truncate(size); 1152 return (0); 1153 } 1154 1155 /* 1156 * When the path is realloc'd, have to fix all of the pointers in structures 1157 * already returned. 1158 */ 1159 static void 1160 fts_padjust(FTS *sp, FTSENT *head) 1161 { 1162 FTSENT *p; 1163 char *addr; 1164 1165 _DIAGASSERT(sp != NULL); 1166 1167 #define ADJUST(p) do { \ 1168 if ((p)->fts_accpath != (p)->fts_name) \ 1169 (p)->fts_accpath = \ 1170 addr + ((p)->fts_accpath - (p)->fts_path); \ 1171 (p)->fts_path = addr; \ 1172 } while (/*CONSTCOND*/0) 1173 1174 addr = sp->fts_path; 1175 1176 /* Adjust the current set of children. */ 1177 for (p = sp->fts_child; p; p = p->fts_link) 1178 ADJUST(p); 1179 1180 /* Adjust the rest of the tree, including the current level. */ 1181 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) { 1182 ADJUST(p); 1183 p = p->fts_link ? p->fts_link : p->fts_parent; 1184 } 1185 } 1186 1187 static size_t 1188 fts_maxarglen(char * const *argv) 1189 { 1190 size_t len, max; 1191 1192 _DIAGASSERT(argv != NULL); 1193 1194 for (max = 0; *argv; ++argv) 1195 if ((len = strlen(*argv)) > max) 1196 max = len; 1197 return (max + 1); 1198 } 1199 1200 /* 1201 * Change to dir specified by fd or p->fts_accpath without getting 1202 * tricked by someone changing the world out from underneath us. 1203 * Assumes p->fts_dev and p->fts_ino are filled in. 1204 */ 1205 static int 1206 fts_safe_changedir(const FTS *sp, const FTSENT *p, int fd, const char *path) 1207 { 1208 int oldfd = fd, ret = -1; 1209 __fts_stat_t sb; 1210 1211 if (ISSET(FTS_NOCHDIR)) 1212 return 0; 1213 1214 if (oldfd < 0 && (fd = open(path, O_RDONLY)) == -1) 1215 return -1; 1216 1217 if (fstat(fd, &sb) == -1) 1218 goto bail; 1219 1220 if (sb.st_ino != p->fts_ino || sb.st_dev != p->fts_dev) { 1221 errno = ENOENT; 1222 goto bail; 1223 } 1224 1225 ret = fchdir(fd); 1226 1227 bail: 1228 if (oldfd < 0) { 1229 int save_errno = errno; 1230 (void)close(fd); 1231 errno = save_errno; 1232 } 1233 return ret; 1234 } 1235