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 #ifndef __minix 60 #define HAVE_STRUCT_DIRENT_D_NAMLEN 61 #endif 62 #endif 63 64 static FTSENT *fts_alloc(FTS *, const char *, size_t); 65 static FTSENT *fts_build(FTS *, int); 66 static void fts_free(FTSENT *); 67 static void fts_lfree(FTSENT *); 68 static void fts_load(FTS *, FTSENT *); 69 static size_t fts_maxarglen(char * const *); 70 static size_t fts_pow2(size_t); 71 static int fts_palloc(FTS *, size_t); 72 static void fts_padjust(FTS *, FTSENT *); 73 static FTSENT *fts_sort(FTS *, FTSENT *, size_t); 74 static unsigned short fts_stat(FTS *, FTSENT *, int); 75 static int fts_safe_changedir(const FTS *, const FTSENT *, int, 76 const char *); 77 78 #if defined(ALIGNBYTES) && defined(ALIGN) 79 #define FTS_ALLOC_ALIGNED 1 80 #else 81 #undef FTS_ALLOC_ALIGNED 82 #endif 83 84 #ifndef ftsent_namelen_truncate 85 #define ftsent_namelen_truncate(a) \ 86 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a)) 87 #endif 88 #ifndef ftsent_pathlen_truncate 89 #define ftsent_pathlen_truncate(a) \ 90 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a)) 91 #endif 92 #ifndef fts_pathlen_truncate 93 #define fts_pathlen_truncate(a) \ 94 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a)) 95 #endif 96 #ifndef fts_nitems_truncate 97 #define fts_nitems_truncate(a) \ 98 ((a) > UINT_MAX ? UINT_MAX : (unsigned int)(a)) 99 #endif 100 101 #define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2]))) 102 103 #define CLR(opt) (sp->fts_options &= ~(opt)) 104 #define ISSET(opt) (sp->fts_options & (opt)) 105 #define SET(opt) (sp->fts_options |= (opt)) 106 107 #define CHDIR(sp, path) (!ISSET(FTS_NOCHDIR) && chdir(path)) 108 #define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) && fchdir(fd)) 109 110 /* fts_build flags */ 111 #define BCHILD 1 /* fts_children */ 112 #define BNAMES 2 /* fts_children, names only */ 113 #define BREAD 3 /* fts_read */ 114 115 #ifndef DTF_HIDEW 116 #undef FTS_WHITEOUT 117 #endif 118 119 FTS * 120 fts_open(char * const *argv, int options, 121 int (*compar)(const FTSENT **, const FTSENT **)) 122 { 123 FTS *sp; 124 FTSENT *p, *root; 125 size_t nitems; 126 FTSENT *parent, *tmp = NULL; /* pacify gcc */ 127 size_t len; 128 129 _DIAGASSERT(argv != NULL); 130 131 /* Options check. */ 132 if (options & ~FTS_OPTIONMASK) { 133 errno = EINVAL; 134 return (NULL); 135 } 136 137 /* Allocate/initialize the stream */ 138 if ((sp = malloc(sizeof(FTS))) == NULL) 139 return (NULL); 140 memset(sp, 0, sizeof(FTS)); 141 sp->fts_compar = compar; 142 sp->fts_options = options; 143 144 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 145 if (ISSET(FTS_LOGICAL)) 146 SET(FTS_NOCHDIR); 147 148 /* 149 * Start out with 1K of path space, and enough, in any case, 150 * to hold the user's paths. 151 */ 152 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN))) 153 goto mem1; 154 155 /* Allocate/initialize root's parent. */ 156 if ((parent = fts_alloc(sp, "", 0)) == NULL) 157 goto mem2; 158 parent->fts_level = FTS_ROOTPARENTLEVEL; 159 160 /* Allocate/initialize root(s). */ 161 for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) { 162 /* Don't allow zero-length paths. */ 163 if ((len = strlen(*argv)) == 0) { 164 errno = ENOENT; 165 goto mem3; 166 } 167 168 if ((p = fts_alloc(sp, *argv, len)) == NULL) 169 goto mem3; 170 p->fts_level = FTS_ROOTLEVEL; 171 p->fts_parent = parent; 172 p->fts_accpath = p->fts_name; 173 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 174 175 /* Command-line "." and ".." are real directories. */ 176 if (p->fts_info == FTS_DOT) 177 p->fts_info = FTS_D; 178 179 /* 180 * If comparison routine supplied, traverse in sorted 181 * order; otherwise traverse in the order specified. 182 */ 183 if (compar) { 184 p->fts_link = root; 185 root = p; 186 } else { 187 p->fts_link = NULL; 188 if (root == NULL) 189 tmp = root = p; 190 else { 191 tmp->fts_link = p; 192 tmp = p; 193 } 194 } 195 } 196 if (compar && nitems > 1) 197 root = fts_sort(sp, root, nitems); 198 199 /* 200 * Allocate a dummy pointer and make fts_read think that we've just 201 * finished the node before the root(s); set p->fts_info to FTS_INIT 202 * so that everything about the "current" node is ignored. 203 */ 204 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 205 goto mem3; 206 sp->fts_cur->fts_link = root; 207 sp->fts_cur->fts_info = FTS_INIT; 208 209 /* 210 * If using chdir(2), grab a file descriptor pointing to dot to ensure 211 * that we can get back here; this could be avoided for some paths, 212 * but almost certainly not worth the effort. Slashes, symbolic links, 213 * and ".." are all fairly nasty problems. Note, if we can't get the 214 * descriptor we run anyway, just more slowly. 215 */ 216 #ifndef O_CLOEXEC 217 #define O_CLOEXEC 0 218 #endif 219 if (!ISSET(FTS_NOCHDIR)) { 220 if ((sp->fts_rfd = open(".", O_RDONLY | O_CLOEXEC, 0)) == -1) 221 SET(FTS_NOCHDIR); 222 } 223 224 if (nitems == 0) 225 fts_free(parent); 226 227 return (sp); 228 229 mem3: fts_lfree(root); 230 fts_free(parent); 231 mem2: free(sp->fts_path); 232 mem1: free(sp); 233 return (NULL); 234 } 235 236 static void 237 fts_load(FTS *sp, FTSENT *p) 238 { 239 size_t len; 240 char *cp; 241 242 _DIAGASSERT(sp != NULL); 243 _DIAGASSERT(p != NULL); 244 245 /* 246 * Load the stream structure for the next traversal. Since we don't 247 * actually enter the directory until after the preorder visit, set 248 * the fts_accpath field specially so the chdir gets done to the right 249 * place and the user can access the first node. From fts_open it's 250 * known that the path will fit. 251 */ 252 len = p->fts_pathlen = p->fts_namelen; 253 memmove(sp->fts_path, p->fts_name, len + 1); 254 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 255 len = strlen(++cp); 256 memmove(p->fts_name, cp, len + 1); 257 p->fts_namelen = ftsent_namelen_truncate(len); 258 } 259 p->fts_accpath = p->fts_path = sp->fts_path; 260 sp->fts_dev = p->fts_dev; 261 } 262 263 int 264 fts_close(FTS *sp) 265 { 266 FTSENT *freep, *p; 267 int saved_errno = 0; 268 269 _DIAGASSERT(sp != NULL); 270 271 /* 272 * This still works if we haven't read anything -- the dummy structure 273 * points to the root list, so we step through to the end of the root 274 * list which has a valid parent pointer. 275 */ 276 if (sp->fts_cur) { 277 if (sp->fts_cur->fts_flags & FTS_SYMFOLLOW) 278 (void)close(sp->fts_cur->fts_symfd); 279 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 280 freep = p; 281 p = p->fts_link ? p->fts_link : p->fts_parent; 282 fts_free(freep); 283 } 284 fts_free(p); 285 } 286 287 /* Free up child linked list, sort array, path buffer. */ 288 if (sp->fts_child) 289 fts_lfree(sp->fts_child); 290 if (sp->fts_array) 291 free(sp->fts_array); 292 free(sp->fts_path); 293 294 /* Return to original directory, save errno if necessary. */ 295 if (!ISSET(FTS_NOCHDIR)) { 296 if (fchdir(sp->fts_rfd) == -1) 297 saved_errno = errno; 298 (void)close(sp->fts_rfd); 299 } 300 301 /* Free up the stream pointer. */ 302 free(sp); 303 if (saved_errno) { 304 errno = saved_errno; 305 return -1; 306 } 307 308 return 0; 309 } 310 311 #if !defined(__FTS_COMPAT_TAILINGSLASH) 312 313 /* 314 * Special case of "/" at the end of the path so that slashes aren't 315 * appended which would cause paths to be written as "....//foo". 316 */ 317 #define NAPPEND(p) \ 318 (p->fts_path[p->fts_pathlen - 1] == '/' \ 319 ? p->fts_pathlen - 1 : p->fts_pathlen) 320 321 #else /* !defined(__FTS_COMPAT_TAILINGSLASH) */ 322 323 /* 324 * compatibility with the old behaviour. 325 * 326 * Special case a root of "/" so that slashes aren't appended which would 327 * cause paths to be written as "//foo". 328 */ 329 330 #define NAPPEND(p) \ 331 (p->fts_level == FTS_ROOTLEVEL && p->fts_pathlen == 1 && \ 332 p->fts_path[0] == '/' ? 0 : p->fts_pathlen) 333 334 #endif /* !defined(__FTS_COMPAT_TAILINGSLASH) */ 335 336 FTSENT * 337 fts_read(FTS *sp) 338 { 339 FTSENT *p, *tmp; 340 int instr; 341 char *t; 342 int saved_errno; 343 344 _DIAGASSERT(sp != NULL); 345 346 /* If finished or unrecoverable error, return NULL. */ 347 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 348 return (NULL); 349 350 /* Set current node pointer. */ 351 p = sp->fts_cur; 352 353 /* Save and zero out user instructions. */ 354 instr = p->fts_instr; 355 p->fts_instr = FTS_NOINSTR; 356 357 /* Any type of file may be re-visited; re-stat and re-turn. */ 358 if (instr == FTS_AGAIN) { 359 p->fts_info = fts_stat(sp, p, 0); 360 return (p); 361 } 362 363 /* 364 * Following a symlink -- SLNONE test allows application to see 365 * SLNONE and recover. If indirecting through a symlink, have 366 * keep a pointer to current location. If unable to get that 367 * pointer, follow fails. 368 */ 369 if (instr == FTS_FOLLOW && 370 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 371 p->fts_info = fts_stat(sp, p, 1); 372 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 373 if ((p->fts_symfd = open(".", O_RDONLY | O_CLOEXEC, 0)) 374 == -1) { 375 p->fts_errno = errno; 376 p->fts_info = FTS_ERR; 377 } else 378 p->fts_flags |= FTS_SYMFOLLOW; 379 } 380 return (p); 381 } 382 383 /* Directory in pre-order. */ 384 if (p->fts_info == FTS_D) { 385 /* If skipped or crossed mount point, do post-order visit. */ 386 if (instr == FTS_SKIP || 387 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) { 388 if (p->fts_flags & FTS_SYMFOLLOW) 389 (void)close(p->fts_symfd); 390 if (sp->fts_child) { 391 fts_lfree(sp->fts_child); 392 sp->fts_child = NULL; 393 } 394 p->fts_info = FTS_DP; 395 return (p); 396 } 397 398 /* Rebuild if only read the names and now traversing. */ 399 if (sp->fts_child && ISSET(FTS_NAMEONLY)) { 400 CLR(FTS_NAMEONLY); 401 fts_lfree(sp->fts_child); 402 sp->fts_child = NULL; 403 } 404 405 /* 406 * Cd to the subdirectory. 407 * 408 * If have already read and now fail to chdir, whack the list 409 * to make the names come out right, and set the parent errno 410 * so the application will eventually get an error condition. 411 * Set the FTS_DONTCHDIR flag so that when we logically change 412 * directories back to the parent we don't do a chdir. 413 * 414 * If haven't read do so. If the read fails, fts_build sets 415 * FTS_STOP or the fts_info field of the node. 416 */ 417 if (sp->fts_child) { 418 if (fts_safe_changedir(sp, p, -1, p->fts_accpath)) { 419 p->fts_errno = errno; 420 p->fts_flags |= FTS_DONTCHDIR; 421 for (p = sp->fts_child; p; p = p->fts_link) 422 p->fts_accpath = 423 p->fts_parent->fts_accpath; 424 } 425 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 426 if (ISSET(FTS_STOP)) 427 return (NULL); 428 return (p); 429 } 430 p = sp->fts_child; 431 sp->fts_child = NULL; 432 goto name; 433 } 434 435 /* Move to the next node on this level. */ 436 next: tmp = p; 437 if ((p = p->fts_link) != NULL) { 438 fts_free(tmp); 439 440 /* 441 * If reached the top, return to the original directory, and 442 * load the paths for the next root. 443 */ 444 if (p->fts_level == FTS_ROOTLEVEL) { 445 if (FCHDIR(sp, sp->fts_rfd)) { 446 SET(FTS_STOP); 447 return (NULL); 448 } 449 fts_load(sp, p); 450 return (sp->fts_cur = p); 451 } 452 453 /* 454 * User may have called fts_set on the node. If skipped, 455 * ignore. If followed, get a file descriptor so we can 456 * get back if necessary. 457 */ 458 if (p->fts_instr == FTS_SKIP) 459 goto next; 460 if (p->fts_instr == FTS_FOLLOW) { 461 p->fts_info = fts_stat(sp, p, 1); 462 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) { 463 if ((p->fts_symfd = 464 open(".", O_RDONLY | O_CLOEXEC, 0)) == -1) { 465 p->fts_errno = errno; 466 p->fts_info = FTS_ERR; 467 } else 468 p->fts_flags |= FTS_SYMFOLLOW; 469 } 470 p->fts_instr = FTS_NOINSTR; 471 } 472 473 name: t = sp->fts_path + NAPPEND(p->fts_parent); 474 *t++ = '/'; 475 memmove(t, p->fts_name, (size_t)(p->fts_namelen + 1)); 476 return (sp->fts_cur = p); 477 } 478 479 /* Move up to the parent node. */ 480 p = tmp->fts_parent; 481 fts_free(tmp); 482 483 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 484 /* 485 * Done; free everything up and set errno to 0 so the user 486 * can distinguish between error and EOF. 487 */ 488 fts_free(p); 489 errno = 0; 490 return (sp->fts_cur = NULL); 491 } 492 493 /* NUL terminate the pathname. */ 494 sp->fts_path[p->fts_pathlen] = '\0'; 495 496 /* 497 * Return to the parent directory. If at a root node or came through 498 * a symlink, go back through the file descriptor. Otherwise, cd up 499 * one directory. 500 */ 501 if (p->fts_level == FTS_ROOTLEVEL) { 502 if (FCHDIR(sp, sp->fts_rfd)) { 503 SET(FTS_STOP); 504 return (NULL); 505 } 506 } else if (p->fts_flags & FTS_SYMFOLLOW) { 507 if (FCHDIR(sp, p->fts_symfd)) { 508 saved_errno = errno; 509 (void)close(p->fts_symfd); 510 errno = saved_errno; 511 SET(FTS_STOP); 512 return (NULL); 513 } 514 (void)close(p->fts_symfd); 515 } else if (!(p->fts_flags & FTS_DONTCHDIR) && 516 fts_safe_changedir(sp, p->fts_parent, -1, "..")) { 517 SET(FTS_STOP); 518 return (NULL); 519 } 520 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 521 return (sp->fts_cur = p); 522 } 523 524 /* 525 * Fts_set takes the stream as an argument although it's not used in this 526 * implementation; it would be necessary if anyone wanted to add global 527 * semantics to fts using fts_set. An error return is allowed for similar 528 * reasons. 529 */ 530 /* ARGSUSED */ 531 int 532 fts_set(FTS *sp, FTSENT *p, int instr) 533 { 534 535 _DIAGASSERT(sp != NULL); 536 _DIAGASSERT(p != NULL); 537 538 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW && 539 instr != FTS_NOINSTR && instr != FTS_SKIP) { 540 errno = EINVAL; 541 return (1); 542 } 543 p->fts_instr = instr; 544 return (0); 545 } 546 547 FTSENT * 548 fts_children(FTS *sp, int instr) 549 { 550 FTSENT *p; 551 int fd; 552 553 _DIAGASSERT(sp != NULL); 554 555 if (instr && instr != FTS_NAMEONLY) { 556 errno = EINVAL; 557 return (NULL); 558 } 559 560 /* Set current node pointer. */ 561 p = sp->fts_cur; 562 563 /* 564 * Errno set to 0 so user can distinguish empty directory from 565 * an error. 566 */ 567 errno = 0; 568 569 /* Fatal errors stop here. */ 570 if (ISSET(FTS_STOP)) 571 return (NULL); 572 573 /* Return logical hierarchy of user's arguments. */ 574 if (p->fts_info == FTS_INIT) 575 return (p->fts_link); 576 577 /* 578 * If not a directory being visited in pre-order, stop here. Could 579 * allow FTS_DNR, assuming the user has fixed the problem, but the 580 * same effect is available with FTS_AGAIN. 581 */ 582 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 583 return (NULL); 584 585 /* Free up any previous child list. */ 586 if (sp->fts_child) 587 fts_lfree(sp->fts_child); 588 589 if (instr == FTS_NAMEONLY) { 590 SET(FTS_NAMEONLY); 591 instr = BNAMES; 592 } else 593 instr = BCHILD; 594 595 /* 596 * If using chdir on a relative path and called BEFORE fts_read does 597 * its chdir to the root of a traversal, we can lose -- we need to 598 * chdir into the subdirectory, and we don't know where the current 599 * directory is, so we can't get back so that the upcoming chdir by 600 * fts_read will work. 601 */ 602 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 603 ISSET(FTS_NOCHDIR)) 604 return (sp->fts_child = fts_build(sp, instr)); 605 606 if ((fd = open(".", O_RDONLY, 0)) == -1) 607 return (sp->fts_child = NULL); 608 sp->fts_child = fts_build(sp, instr); 609 if (fchdir(fd)) { 610 (void)close(fd); 611 return (NULL); 612 } 613 (void)close(fd); 614 return (sp->fts_child); 615 } 616 617 /* 618 * This is the tricky part -- do not casually change *anything* in here. The 619 * idea is to build the linked list of entries that are used by fts_children 620 * and fts_read. There are lots of special cases. 621 * 622 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 623 * set and it's a physical walk (so that symbolic links can't be directories), 624 * we can do things quickly. First, if it's a 4.4BSD file system, the type 625 * of the file is in the directory entry. Otherwise, we assume that the number 626 * of subdirectories in a node is equal to the number of links to the parent. 627 * The former skips all stat calls. The latter skips stat calls in any leaf 628 * directories and for any files after the subdirectories in the directory have 629 * been found, cutting the stat calls by about 2/3. 630 */ 631 static FTSENT * 632 fts_build(FTS *sp, int type) 633 { 634 struct dirent *dp; 635 FTSENT *p, *head; 636 size_t nitems; 637 FTSENT *cur, *tail; 638 DIR *dirp; 639 void *oldaddr; 640 size_t dnamlen; 641 int cderrno, descend, level, nlinks, saved_errno, nostat, doadjust; 642 size_t len, maxlen; 643 #ifdef FTS_WHITEOUT 644 int oflag; 645 #endif 646 char *cp = NULL; /* pacify gcc */ 647 648 _DIAGASSERT(sp != NULL); 649 650 /* Set current node pointer. */ 651 cur = sp->fts_cur; 652 653 /* 654 * Open the directory for reading. If this fails, we're done. 655 * If being called from fts_read, set the fts_info field. 656 */ 657 #ifdef FTS_WHITEOUT 658 if (ISSET(FTS_WHITEOUT)) 659 oflag = DTF_NODUP|DTF_REWIND; 660 else 661 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND; 662 #else 663 #define __opendir2(path, flag) opendir(path) 664 #endif 665 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 666 if (type == BREAD) { 667 cur->fts_info = FTS_DNR; 668 cur->fts_errno = errno; 669 } 670 return (NULL); 671 } 672 673 /* 674 * Nlinks is the number of possible entries of type directory in the 675 * directory if we're cheating on stat calls, 0 if we're not doing 676 * any stat calls at all, -1 if we're doing stats on everything. 677 */ 678 if (type == BNAMES) { 679 nlinks = 0; 680 nostat = 1; 681 } else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) { 682 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 683 nostat = 1; 684 } else { 685 nlinks = -1; 686 nostat = 0; 687 } 688 689 #ifdef notdef 690 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 691 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 692 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 693 #endif 694 /* 695 * If we're going to need to stat anything or we want to descend 696 * and stay in the directory, chdir. If this fails we keep going, 697 * but set a flag so we don't chdir after the post-order visit. 698 * We won't be able to stat anything, but we can still return the 699 * names themselves. Note, that since fts_read won't be able to 700 * chdir into the directory, it will have to return different path 701 * names than before, i.e. "a/b" instead of "b". Since the node 702 * has already been visited in pre-order, have to wait until the 703 * post-order visit to return the error. There is a special case 704 * here, if there was nothing to stat then it's not an error to 705 * not be able to stat. This is all fairly nasty. If a program 706 * needed sorted entries or stat information, they had better be 707 * checking FTS_NS on the returned nodes. 708 */ 709 cderrno = 0; 710 if (nlinks || type == BREAD) { 711 if (fts_safe_changedir(sp, cur, dirfd(dirp), NULL)) { 712 if (nlinks && type == BREAD) 713 cur->fts_errno = errno; 714 cur->fts_flags |= FTS_DONTCHDIR; 715 descend = 0; 716 cderrno = errno; 717 } else 718 descend = 1; 719 } else 720 descend = 0; 721 722 /* 723 * Figure out the max file name length that can be stored in the 724 * current path -- the inner loop allocates more path as necessary. 725 * We really wouldn't have to do the maxlen calculations here, we 726 * could do them in fts_read before returning the path, but it's a 727 * lot easier here since the length is part of the dirent structure. 728 * 729 * If not changing directories set a pointer so that can just append 730 * each new name into the path. 731 */ 732 len = NAPPEND(cur); 733 if (ISSET(FTS_NOCHDIR)) { 734 cp = sp->fts_path + len; 735 *cp++ = '/'; 736 } 737 len++; 738 maxlen = sp->fts_pathlen - len; 739 740 #if defined(__FTS_COMPAT_LEVEL) 741 if (cur->fts_level == SHRT_MAX) { 742 (void)closedir(dirp); 743 cur->fts_info = FTS_ERR; 744 SET(FTS_STOP); 745 errno = ENAMETOOLONG; 746 return (NULL); 747 } 748 #endif 749 750 level = cur->fts_level + 1; 751 752 /* Read the directory, attaching each entry to the `link' pointer. */ 753 doadjust = 0; 754 for (head = tail = NULL, nitems = 0; (dp = readdir(dirp)) != NULL;) { 755 756 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 757 continue; 758 759 #if defined(HAVE_STRUCT_DIRENT_D_NAMLEN) 760 dnamlen = dp->d_namlen; 761 #else 762 dnamlen = strlen(dp->d_name); 763 #endif 764 if ((p = fts_alloc(sp, dp->d_name, dnamlen)) == NULL) 765 goto mem1; 766 if (dnamlen >= maxlen) { /* include space for NUL */ 767 oldaddr = sp->fts_path; 768 if (fts_palloc(sp, dnamlen + len + 1)) { 769 /* 770 * No more memory for path or structures. Save 771 * errno, free up the current structure and the 772 * structures already allocated. 773 */ 774 mem1: saved_errno = errno; 775 if (p) 776 fts_free(p); 777 fts_lfree(head); 778 (void)closedir(dirp); 779 errno = saved_errno; 780 cur->fts_info = FTS_ERR; 781 SET(FTS_STOP); 782 return (NULL); 783 } 784 /* Did realloc() change the pointer? */ 785 if (oldaddr != sp->fts_path) { 786 doadjust = 1; 787 if (ISSET(FTS_NOCHDIR)) 788 cp = sp->fts_path + len; 789 } 790 maxlen = sp->fts_pathlen - len; 791 } 792 793 #if defined(__FTS_COMPAT_LENGTH) 794 if (len + dnamlen >= USHRT_MAX) { 795 /* 796 * In an FTSENT, fts_pathlen is an unsigned short 797 * so it is possible to wraparound here. 798 * If we do, free up the current structure and the 799 * structures already allocated, then error out 800 * with ENAMETOOLONG. 801 */ 802 fts_free(p); 803 fts_lfree(head); 804 (void)closedir(dirp); 805 cur->fts_info = FTS_ERR; 806 SET(FTS_STOP); 807 errno = ENAMETOOLONG; 808 return (NULL); 809 } 810 #endif 811 p->fts_level = level; 812 p->fts_pathlen = ftsent_pathlen_truncate(len + dnamlen); 813 p->fts_parent = sp->fts_cur; 814 815 #ifdef FTS_WHITEOUT 816 if (dp->d_type == DT_WHT) 817 p->fts_flags |= FTS_ISW; 818 #endif 819 820 if (cderrno) { 821 if (nlinks) { 822 p->fts_info = FTS_NS; 823 p->fts_errno = cderrno; 824 } else 825 p->fts_info = FTS_NSOK; 826 p->fts_accpath = cur->fts_accpath; 827 } else if (nlinks == 0 828 #ifdef DT_DIR 829 || (nostat && 830 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN) 831 #endif 832 ) { 833 p->fts_accpath = 834 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 835 p->fts_info = FTS_NSOK; 836 } else { 837 /* Build a file name for fts_stat to stat. */ 838 if (ISSET(FTS_NOCHDIR)) { 839 p->fts_accpath = p->fts_path; 840 memmove(cp, p->fts_name, 841 (size_t)(p->fts_namelen + 1)); 842 } else 843 p->fts_accpath = p->fts_name; 844 /* Stat it. */ 845 p->fts_info = fts_stat(sp, p, 0); 846 847 /* Decrement link count if applicable. */ 848 if (nlinks > 0 && (p->fts_info == FTS_D || 849 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 850 --nlinks; 851 } 852 853 /* We walk in directory order so "ls -f" doesn't get upset. */ 854 p->fts_link = NULL; 855 if (head == NULL) 856 head = tail = p; 857 else { 858 tail->fts_link = p; 859 tail = p; 860 } 861 ++nitems; 862 } 863 (void)closedir(dirp); 864 865 /* 866 * If had to realloc the path, adjust the addresses for the rest 867 * of the tree. 868 */ 869 if (doadjust) 870 fts_padjust(sp, head); 871 872 /* 873 * If not changing directories, reset the path back to original 874 * state. 875 */ 876 if (ISSET(FTS_NOCHDIR)) { 877 if (len == sp->fts_pathlen || nitems == 0) 878 --cp; 879 *cp = '\0'; 880 } 881 882 /* 883 * If descended after called from fts_children or after called from 884 * fts_read and nothing found, get back. At the root level we use 885 * the saved fd; if one of fts_open()'s arguments is a relative path 886 * to an empty directory, we wind up here with no other way back. If 887 * can't get back, we're done. 888 */ 889 if (descend && (type == BCHILD || !nitems) && 890 (cur->fts_level == FTS_ROOTLEVEL ? 891 FCHDIR(sp, sp->fts_rfd) : 892 fts_safe_changedir(sp, cur->fts_parent, -1, ".."))) { 893 cur->fts_info = FTS_ERR; 894 SET(FTS_STOP); 895 return (NULL); 896 } 897 898 /* If didn't find anything, return NULL. */ 899 if (!nitems) { 900 if (type == BREAD) 901 cur->fts_info = FTS_DP; 902 return (NULL); 903 } 904 905 /* Sort the entries. */ 906 if (sp->fts_compar && nitems > 1) 907 head = fts_sort(sp, head, nitems); 908 return (head); 909 } 910 911 static unsigned short 912 fts_stat(FTS *sp, FTSENT *p, int follow) 913 { 914 FTSENT *t; 915 dev_t dev; 916 __fts_ino_t ino; 917 __fts_stat_t *sbp, sb; 918 int saved_errno; 919 920 _DIAGASSERT(sp != NULL); 921 _DIAGASSERT(p != NULL); 922 923 /* If user needs stat info, stat buffer already allocated. */ 924 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 925 926 #ifdef FTS_WHITEOUT 927 /* check for whiteout */ 928 if (p->fts_flags & FTS_ISW) { 929 if (sbp != &sb) { 930 memset(sbp, '\0', sizeof (*sbp)); 931 sbp->st_mode = S_IFWHT; 932 } 933 return (FTS_W); 934 } 935 #endif 936 937 /* 938 * If doing a logical walk, or application requested FTS_FOLLOW, do 939 * a stat(2). If that fails, check for a non-existent symlink. If 940 * fail, set the errno from the stat call. 941 */ 942 if (ISSET(FTS_LOGICAL) || follow) { 943 if (stat(p->fts_accpath, sbp)) { 944 saved_errno = errno; 945 if (!lstat(p->fts_accpath, sbp)) { 946 errno = 0; 947 return (FTS_SLNONE); 948 } 949 p->fts_errno = saved_errno; 950 goto err; 951 } 952 } else if (lstat(p->fts_accpath, sbp)) { 953 p->fts_errno = errno; 954 err: memset(sbp, 0, sizeof(*sbp)); 955 return (FTS_NS); 956 } 957 958 if (S_ISDIR(sbp->st_mode)) { 959 /* 960 * Set the device/inode. Used to find cycles and check for 961 * crossing mount points. Also remember the link count, used 962 * in fts_build to limit the number of stat calls. It is 963 * understood that these fields are only referenced if fts_info 964 * is set to FTS_D. 965 */ 966 dev = p->fts_dev = sbp->st_dev; 967 ino = p->fts_ino = sbp->st_ino; 968 p->fts_nlink = sbp->st_nlink; 969 970 if (ISDOT(p->fts_name)) 971 return (FTS_DOT); 972 973 /* 974 * Cycle detection is done by brute force when the directory 975 * is first encountered. If the tree gets deep enough or the 976 * number of symbolic links to directories is high enough, 977 * something faster might be worthwhile. 978 */ 979 for (t = p->fts_parent; 980 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 981 if (ino == t->fts_ino && dev == t->fts_dev) { 982 p->fts_cycle = t; 983 return (FTS_DC); 984 } 985 return (FTS_D); 986 } 987 if (S_ISLNK(sbp->st_mode)) 988 return (FTS_SL); 989 if (S_ISREG(sbp->st_mode)) 990 return (FTS_F); 991 return (FTS_DEFAULT); 992 } 993 994 static FTSENT * 995 fts_sort(FTS *sp, FTSENT *head, size_t nitems) 996 { 997 FTSENT **ap, *p; 998 999 _DIAGASSERT(sp != NULL); 1000 _DIAGASSERT(head != NULL); 1001 1002 /* 1003 * Construct an array of pointers to the structures and call qsort(3). 1004 * Reassemble the array in the order returned by qsort. If unable to 1005 * sort for memory reasons, return the directory entries in their 1006 * current order. Allocate enough space for the current needs plus 1007 * 40 so don't realloc one entry at a time. 1008 */ 1009 if (nitems > sp->fts_nitems) { 1010 FTSENT **new; 1011 1012 new = realloc(sp->fts_array, sizeof(FTSENT *) * (nitems + 40)); 1013 if (new == 0) 1014 return (head); 1015 sp->fts_array = new; 1016 sp->fts_nitems = fts_nitems_truncate(nitems + 40); 1017 } 1018 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 1019 *ap++ = p; 1020 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), 1021 (int (*)(const void *, const void *))sp->fts_compar); 1022 for (head = *(ap = sp->fts_array); --nitems; ++ap) 1023 ap[0]->fts_link = ap[1]; 1024 ap[0]->fts_link = NULL; 1025 return (head); 1026 } 1027 1028 static FTSENT * 1029 fts_alloc(FTS *sp, const char *name, size_t namelen) 1030 { 1031 FTSENT *p; 1032 #if defined(FTS_ALLOC_ALIGNED) 1033 size_t len; 1034 #endif 1035 1036 _DIAGASSERT(sp != NULL); 1037 _DIAGASSERT(name != NULL); 1038 1039 #if defined(FTS_ALLOC_ALIGNED) 1040 /* 1041 * The file name is a variable length array and no stat structure is 1042 * necessary if the user has set the nostat bit. Allocate the FTSENT 1043 * structure, the file name and the stat structure in one chunk, but 1044 * be careful that the stat structure is reasonably aligned. Since the 1045 * fts_name field is declared to be of size 1, the fts_name pointer is 1046 * namelen + 2 before the first possible address of the stat structure. 1047 */ 1048 len = sizeof(FTSENT) + namelen; 1049 if (!ISSET(FTS_NOSTAT)) 1050 len += sizeof(*(p->fts_statp)) + ALIGNBYTES; 1051 if ((p = malloc(len)) == NULL) 1052 return (NULL); 1053 1054 if (!ISSET(FTS_NOSTAT)) 1055 p->fts_statp = (__fts_stat_t *)ALIGN( 1056 (unsigned long)(p->fts_name + namelen + 2)); 1057 #else 1058 if ((p = malloc(sizeof(FTSENT) + namelen)) == NULL) 1059 return (NULL); 1060 1061 if (!ISSET(FTS_NOSTAT)) 1062 if ((p->fts_statp = malloc(sizeof(*(p->fts_statp)))) == NULL) { 1063 free(p); 1064 return (NULL); 1065 } 1066 #endif 1067 1068 if (ISSET(FTS_NOSTAT)) 1069 p->fts_statp = NULL; 1070 1071 /* Copy the name plus the trailing NULL. */ 1072 memmove(p->fts_name, name, namelen + 1); 1073 1074 p->fts_namelen = ftsent_namelen_truncate(namelen); 1075 p->fts_path = sp->fts_path; 1076 p->fts_errno = 0; 1077 p->fts_flags = 0; 1078 p->fts_instr = FTS_NOINSTR; 1079 p->fts_number = 0; 1080 p->fts_pointer = NULL; 1081 return (p); 1082 } 1083 1084 static void 1085 fts_free(FTSENT *p) 1086 { 1087 #if !defined(FTS_ALLOC_ALIGNED) 1088 if (p->fts_statp) 1089 free(p->fts_statp); 1090 #endif 1091 free(p); 1092 } 1093 1094 static void 1095 fts_lfree(FTSENT *head) 1096 { 1097 FTSENT *p; 1098 1099 /* XXX: head may be NULL ? */ 1100 1101 /* Free a linked list of structures. */ 1102 while ((p = head) != NULL) { 1103 head = head->fts_link; 1104 fts_free(p); 1105 } 1106 } 1107 1108 static size_t 1109 fts_pow2(size_t x) 1110 { 1111 1112 x--; 1113 x |= x>>1; 1114 x |= x>>2; 1115 x |= x>>4; 1116 x |= x>>8; 1117 x |= x>>16; 1118 #if LONG_BIT > 32 1119 x |= x>>32; 1120 #endif 1121 #if LONG_BIT > 64 1122 x |= x>>64; 1123 #endif 1124 x++; 1125 return (x); 1126 } 1127 1128 /* 1129 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 1130 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 1131 * though the kernel won't resolve them. Round up the new size to a power of 2, 1132 * so we don't realloc the path 2 bytes at a time. 1133 */ 1134 static int 1135 fts_palloc(FTS *sp, size_t size) 1136 { 1137 char *new; 1138 1139 _DIAGASSERT(sp != NULL); 1140 1141 #ifdef __FTS_COMPAT_LENGTH 1142 /* Protect against fts_pathlen overflow. */ 1143 if (size > USHRT_MAX + 1) { 1144 errno = ENAMETOOLONG; 1145 return (1); 1146 } 1147 #endif 1148 size = fts_pow2(size); 1149 new = realloc(sp->fts_path, size); 1150 if (new == 0) 1151 return (1); 1152 sp->fts_path = new; 1153 sp->fts_pathlen = fts_pathlen_truncate(size); 1154 return (0); 1155 } 1156 1157 /* 1158 * When the path is realloc'd, have to fix all of the pointers in structures 1159 * already returned. 1160 */ 1161 static void 1162 fts_padjust(FTS *sp, FTSENT *head) 1163 { 1164 FTSENT *p; 1165 char *addr; 1166 1167 _DIAGASSERT(sp != NULL); 1168 1169 #define ADJUST(p) do { \ 1170 if ((p)->fts_accpath != (p)->fts_name) \ 1171 (p)->fts_accpath = \ 1172 addr + ((p)->fts_accpath - (p)->fts_path); \ 1173 (p)->fts_path = addr; \ 1174 } while (/*CONSTCOND*/0) 1175 1176 addr = sp->fts_path; 1177 1178 /* Adjust the current set of children. */ 1179 for (p = sp->fts_child; p; p = p->fts_link) 1180 ADJUST(p); 1181 1182 /* Adjust the rest of the tree, including the current level. */ 1183 for (p = head; p->fts_level >= FTS_ROOTLEVEL;) { 1184 ADJUST(p); 1185 p = p->fts_link ? p->fts_link : p->fts_parent; 1186 } 1187 } 1188 1189 static size_t 1190 fts_maxarglen(char * const *argv) 1191 { 1192 size_t len, max; 1193 1194 _DIAGASSERT(argv != NULL); 1195 1196 for (max = 0; *argv; ++argv) 1197 if ((len = strlen(*argv)) > max) 1198 max = len; 1199 return (max + 1); 1200 } 1201 1202 /* 1203 * Change to dir specified by fd or p->fts_accpath without getting 1204 * tricked by someone changing the world out from underneath us. 1205 * Assumes p->fts_dev and p->fts_ino are filled in. 1206 */ 1207 static int 1208 fts_safe_changedir(const FTS *sp, const FTSENT *p, int fd, const char *path) 1209 { 1210 int oldfd = fd, ret = -1; 1211 __fts_stat_t sb; 1212 1213 if (ISSET(FTS_NOCHDIR)) 1214 return 0; 1215 1216 if (oldfd < 0 && (fd = open(path, O_RDONLY)) == -1) 1217 return -1; 1218 1219 if (fstat(fd, &sb) == -1) 1220 goto bail; 1221 1222 if (sb.st_ino != p->fts_ino || sb.st_dev != p->fts_dev) { 1223 errno = ENOENT; 1224 goto bail; 1225 } 1226 1227 ret = fchdir(fd); 1228 1229 bail: 1230 if (oldfd < 0) { 1231 int save_errno = errno; 1232 (void)close(fd); 1233 errno = save_errno; 1234 } 1235 return ret; 1236 } 1237 1238 #if defined(__minix) && defined(__weak_alias) 1239 __weak_alias(fts_children, __fts_children60) 1240 __weak_alias(fts_close, __fts_close60) 1241 __weak_alias(fts_open, __fts_open60) 1242 __weak_alias(fts_read, __fts_read60) 1243 __weak_alias(fts_set, __fts_set60) 1244 #endif 1245