fts.c revision 1.18
1/* $NetBSD: fts.c,v 1.18 1997/10/08 19:56:59 pk 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36#include <sys/cdefs.h> 37#if defined(LIBC_SCCS) && !defined(lint) 38#if 0 39static char sccsid[] = "@(#)fts.c 8.4 (Berkeley) 4/16/94"; 40#else 41__RCSID("$NetBSD: fts.c,v 1.18 1997/10/08 19:56:59 pk 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 <dirent.h> 50#include <errno.h> 51#include <fcntl.h> 52#include <fts.h> 53#include <stdlib.h> 54#include <string.h> 55#include <unistd.h> 56 57#ifdef __weak_alias 58__weak_alias(fts_children,_fts_children); 59__weak_alias(fts_close,_fts_close); 60__weak_alias(fts_open,_fts_open); 61__weak_alias(fts_read,_fts_read); 62__weak_alias(fts_set,_fts_set); 63#endif 64 65static FTSENT *fts_alloc __P((FTS *, char *, int)); 66static FTSENT *fts_build __P((FTS *, int)); 67static void fts_lfree __P((FTSENT *)); 68static void fts_load __P((FTS *, FTSENT *)); 69static size_t fts_maxarglen __P((char * const *)); 70static void fts_padjust __P((FTS *, void *)); 71static int fts_palloc __P((FTS *, size_t)); 72static FTSENT *fts_sort __P((FTS *, FTSENT *, int)); 73static u_short fts_stat __P((FTS *, FTSENT *, int)); 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 89FTS * 90fts_open(argv, options, compar) 91 char * const *argv; 92 register int options; 93 int (*compar) __P((const FTSENT **, const FTSENT **)); 94{ 95 register FTS *sp; 96 register FTSENT *p, *root; 97 register int nitems; 98 FTSENT *parent, *tmp = NULL; /* pacify gcc */ 99 int len; 100 101 /* Options check. */ 102 if (options & ~FTS_OPTIONMASK) { 103 errno = EINVAL; 104 return (NULL); 105 } 106 107 /* Allocate/initialize the stream */ 108 if ((sp = malloc((u_int)sizeof(FTS))) == NULL) 109 return (NULL); 110 memset(sp, 0, sizeof(FTS)); 111 sp->fts_compar = compar; 112 sp->fts_options = options; 113 114 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 115 if (ISSET(FTS_LOGICAL)) 116 SET(FTS_NOCHDIR); 117 118 /* 119 * Start out with 1K of path space, and enough, in any case, 120 * to hold the user's paths. 121 */ 122 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN))) 123 goto mem1; 124 125 /* Allocate/initialize root's parent. */ 126 if ((parent = fts_alloc(sp, "", 0)) == NULL) 127 goto mem2; 128 parent->fts_level = FTS_ROOTPARENTLEVEL; 129 130 /* Allocate/initialize root(s). */ 131 for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) { 132 /* Don't allow zero-length paths. */ 133 if ((len = strlen(*argv)) == 0) { 134 errno = ENOENT; 135 goto mem3; 136 } 137 138 /* 139 * Special case of "/" at the end of the path so that 140 * slashes aren't appended which would cause paths to 141 * be written as "....//foo". 142 * Note that we cannot handle a single '/' here. That 143 * case is dealt with specially later (sigh); see the 144 * NAPPEND() macro below. 145 */ 146 if (len > 1 && (*argv)[len-1] == '/') 147 len--; 148 149 p = fts_alloc(sp, *argv, len); 150 p->fts_level = FTS_ROOTLEVEL; 151 p->fts_parent = parent; 152 p->fts_accpath = p->fts_name; 153 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 154 155 /* Command-line "." and ".." are real directories. */ 156 if (p->fts_info == FTS_DOT) 157 p->fts_info = FTS_D; 158 159 /* 160 * If comparison routine supplied, traverse in sorted 161 * order; otherwise traverse in the order specified. 162 */ 163 if (compar) { 164 p->fts_link = root; 165 root = p; 166 } else { 167 p->fts_link = NULL; 168 if (root == NULL) 169 tmp = root = p; 170 else { 171 tmp->fts_link = p; 172 tmp = p; 173 } 174 } 175 } 176 if (compar && nitems > 1) 177 root = fts_sort(sp, root, nitems); 178 179 /* 180 * Allocate a dummy pointer and make fts_read think that we've just 181 * finished the node before the root(s); set p->fts_info to FTS_INIT 182 * so that everything about the "current" node is ignored. 183 */ 184 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 185 goto mem3; 186 sp->fts_cur->fts_link = root; 187 sp->fts_cur->fts_info = FTS_INIT; 188 189 /* 190 * If using chdir(2), grab a file descriptor pointing to dot to insure 191 * that we can get back here; this could be avoided for some paths, 192 * but almost certainly not worth the effort. Slashes, symbolic links, 193 * and ".." are all fairly nasty problems. Note, if we can't get the 194 * descriptor we run anyway, just more slowly. 195 */ 196 if (!ISSET(FTS_NOCHDIR) && (sp->fts_rfd = open(".", O_RDONLY, 0)) < 0) 197 SET(FTS_NOCHDIR); 198 199 return (sp); 200 201mem3: fts_lfree(root); 202 free(parent); 203mem2: free(sp->fts_path); 204mem1: free(sp); 205 return (NULL); 206} 207 208static void 209fts_load(sp, p) 210 FTS *sp; 211 register FTSENT *p; 212{ 213 register int len; 214 register char *cp; 215 216 /* 217 * Load the stream structure for the next traversal. Since we don't 218 * actually enter the directory until after the preorder visit, set 219 * the fts_accpath field specially so the chdir gets done to the right 220 * place and the user can access the first node. From fts_open it's 221 * known that the path will fit. 222 */ 223 len = p->fts_pathlen = p->fts_namelen; 224 memmove(sp->fts_path, p->fts_name, len + 1); 225 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 226 len = strlen(++cp); 227 memmove(p->fts_name, cp, len + 1); 228 p->fts_namelen = len; 229 } 230 p->fts_accpath = p->fts_path = sp->fts_path; 231 sp->fts_dev = p->fts_dev; 232} 233 234int 235fts_close(sp) 236 FTS *sp; 237{ 238 register FTSENT *freep, *p; 239 int saved_errno = 0; /* pacify gcc */ 240 241 /* 242 * This still works if we haven't read anything -- the dummy structure 243 * points to the root list, so we step through to the end of the root 244 * list which has a valid parent pointer. 245 */ 246 if (sp->fts_cur) { 247 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 248 freep = p; 249 p = p->fts_link ? p->fts_link : p->fts_parent; 250 free(freep); 251 } 252 free(p); 253 } 254 255 /* Free up child linked list, sort array, path buffer. */ 256 if (sp->fts_child) 257 fts_lfree(sp->fts_child); 258 if (sp->fts_array) 259 free(sp->fts_array); 260 free(sp->fts_path); 261 262 /* Return to original directory, save errno if necessary. */ 263 if (!ISSET(FTS_NOCHDIR)) { 264 saved_errno = fchdir(sp->fts_rfd) ? errno : 0; 265 (void)close(sp->fts_rfd); 266 } 267 268 /* Free up the stream pointer. */ 269 free(sp); 270 271 /* Set errno and return. */ 272 if (!ISSET(FTS_NOCHDIR) && saved_errno) { 273 errno = saved_errno; 274 return (-1); 275 } 276 return (0); 277} 278 279/* 280 * Special case a root of "/" so that slashes aren't appended which would 281 * cause paths to be written as "//foo". Note, this is a special case 282 * of the special cases that are dealt with in fts_open()... 283 */ 284#define NAPPEND(p) \ 285 (p->fts_level == FTS_ROOTLEVEL && p->fts_pathlen == 1 &&\ 286 p->fts_path[0] == '/' ? 0 : p->fts_pathlen) 287 288FTSENT * 289fts_read(sp) 290 register FTS *sp; 291{ 292 register FTSENT *p, *tmp; 293 register int instr; 294 register char *t; 295 int saved_errno; 296 297 /* If finished or unrecoverable error, return NULL. */ 298 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 299 return (NULL); 300 301 /* Set current node pointer. */ 302 p = sp->fts_cur; 303 304 /* Save and zero out user instructions. */ 305 instr = p->fts_instr; 306 p->fts_instr = FTS_NOINSTR; 307 308 /* Any type of file may be re-visited; re-stat and re-turn. */ 309 if (instr == FTS_AGAIN) { 310 p->fts_info = fts_stat(sp, p, 0); 311 return (p); 312 } 313 314 /* 315 * Following a symlink -- SLNONE test allows application to see 316 * SLNONE and recover. If indirecting through a symlink, have 317 * keep a pointer to current location. If unable to get that 318 * pointer, follow fails. 319 */ 320 if (instr == FTS_FOLLOW && 321 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 322 p->fts_info = fts_stat(sp, p, 1); 323 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) 324 if ((p->fts_symfd = open(".", O_RDONLY, 0)) < 0) { 325 p->fts_errno = errno; 326 p->fts_info = FTS_ERR; 327 } else 328 p->fts_flags |= FTS_SYMFOLLOW; 329 return (p); 330 } 331 332 /* Directory in pre-order. */ 333 if (p->fts_info == FTS_D) { 334 /* If skipped or crossed mount point, do post-order visit. */ 335 if (instr == FTS_SKIP || 336 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) { 337 if (p->fts_flags & FTS_SYMFOLLOW) 338 (void)close(p->fts_symfd); 339 if (sp->fts_child) { 340 fts_lfree(sp->fts_child); 341 sp->fts_child = NULL; 342 } 343 p->fts_info = FTS_DP; 344 return (p); 345 } 346 347 /* Rebuild if only read the names and now traversing. */ 348 if (sp->fts_child && ISSET(FTS_NAMEONLY)) { 349 CLR(FTS_NAMEONLY); 350 fts_lfree(sp->fts_child); 351 sp->fts_child = NULL; 352 } 353 354 /* 355 * Cd to the subdirectory. 356 * 357 * If have already read and now fail to chdir, whack the list 358 * to make the names come out right, and set the parent errno 359 * so the application will eventually get an error condition. 360 * Set the FTS_DONTCHDIR flag so that when we logically change 361 * directories back to the parent we don't do a chdir. 362 * 363 * If haven't read do so. If the read fails, fts_build sets 364 * FTS_STOP or the fts_info field of the node. 365 */ 366 if (sp->fts_child) { 367 if (CHDIR(sp, p->fts_accpath)) { 368 p->fts_errno = errno; 369 p->fts_flags |= FTS_DONTCHDIR; 370 for (p = sp->fts_child; p; p = p->fts_link) 371 p->fts_accpath = 372 p->fts_parent->fts_accpath; 373 } 374 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 375 if (ISSET(FTS_STOP)) 376 return (NULL); 377 return (p); 378 } 379 p = sp->fts_child; 380 sp->fts_child = NULL; 381 goto name; 382 } 383 384 /* Move to the next node on this level. */ 385next: tmp = p; 386 if ((p = p->fts_link) != NULL) { 387 free(tmp); 388 389 /* 390 * If reached the top, return to the original directory, and 391 * load the paths for the next root. 392 */ 393 if (p->fts_level == FTS_ROOTLEVEL) { 394 if (!ISSET(FTS_NOCHDIR) && FCHDIR(sp, sp->fts_rfd)) { 395 SET(FTS_STOP); 396 return (NULL); 397 } 398 fts_load(sp, p); 399 return (sp->fts_cur = p); 400 } 401 402 /* 403 * User may have called fts_set on the node. If skipped, 404 * ignore. If followed, get a file descriptor so we can 405 * get back if necessary. 406 */ 407 if (p->fts_instr == FTS_SKIP) 408 goto next; 409 if (p->fts_instr == FTS_FOLLOW) { 410 p->fts_info = fts_stat(sp, p, 1); 411 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) 412 if ((p->fts_symfd = 413 open(".", O_RDONLY, 0)) < 0) { 414 p->fts_errno = errno; 415 p->fts_info = FTS_ERR; 416 } else 417 p->fts_flags |= FTS_SYMFOLLOW; 418 p->fts_instr = FTS_NOINSTR; 419 } 420 421name: t = sp->fts_path + NAPPEND(p->fts_parent); 422 *t++ = '/'; 423 memmove(t, p->fts_name, p->fts_namelen + 1); 424 return (sp->fts_cur = p); 425 } 426 427 /* Move up to the parent node. */ 428 p = tmp->fts_parent; 429 free(tmp); 430 431 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 432 /* 433 * Done; free everything up and set errno to 0 so the user 434 * can distinguish between error and EOF. 435 */ 436 free(p); 437 errno = 0; 438 return (sp->fts_cur = NULL); 439 } 440 441 /* Nul terminate the pathname. */ 442 sp->fts_path[p->fts_pathlen] = '\0'; 443 444 /* 445 * Return to the parent directory. If at a root node or came through 446 * a symlink, go back through the file descriptor. Otherwise, cd up 447 * one directory. 448 */ 449 if (p->fts_level == FTS_ROOTLEVEL) { 450 if (!ISSET(FTS_NOCHDIR) && FCHDIR(sp, sp->fts_rfd)) { 451 SET(FTS_STOP); 452 return (NULL); 453 } 454 } else if (p->fts_flags & FTS_SYMFOLLOW) { 455 if (FCHDIR(sp, p->fts_symfd)) { 456 saved_errno = errno; 457 (void)close(p->fts_symfd); 458 errno = saved_errno; 459 SET(FTS_STOP); 460 return (NULL); 461 } 462 (void)close(p->fts_symfd); 463 } else if (!(p->fts_flags & FTS_DONTCHDIR)) { 464 if (CHDIR(sp, "..")) { 465 SET(FTS_STOP); 466 return (NULL); 467 } 468 } 469 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 470 return (sp->fts_cur = p); 471} 472 473/* 474 * Fts_set takes the stream as an argument although it's not used in this 475 * implementation; it would be necessary if anyone wanted to add global 476 * semantics to fts using fts_set. An error return is allowed for similar 477 * reasons. 478 */ 479/* ARGSUSED */ 480int 481fts_set(sp, p, instr) 482 FTS *sp; 483 FTSENT *p; 484 int instr; 485{ 486 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW && 487 instr != FTS_NOINSTR && instr != FTS_SKIP) { 488 errno = EINVAL; 489 return (1); 490 } 491 p->fts_instr = instr; 492 return (0); 493} 494 495FTSENT * 496fts_children(sp, instr) 497 register FTS *sp; 498 int instr; 499{ 500 register FTSENT *p; 501 int fd; 502 503 if (instr && instr != FTS_NAMEONLY) { 504 errno = EINVAL; 505 return (NULL); 506 } 507 508 /* Set current node pointer. */ 509 p = sp->fts_cur; 510 511 /* 512 * Errno set to 0 so user can distinguish empty directory from 513 * an error. 514 */ 515 errno = 0; 516 517 /* Fatal errors stop here. */ 518 if (ISSET(FTS_STOP)) 519 return (NULL); 520 521 /* Return logical hierarchy of user's arguments. */ 522 if (p->fts_info == FTS_INIT) 523 return (p->fts_link); 524 525 /* 526 * If not a directory being visited in pre-order, stop here. Could 527 * allow FTS_DNR, assuming the user has fixed the problem, but the 528 * same effect is available with FTS_AGAIN. 529 */ 530 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 531 return (NULL); 532 533 /* Free up any previous child list. */ 534 if (sp->fts_child) 535 fts_lfree(sp->fts_child); 536 537 if (instr == FTS_NAMEONLY) { 538 SET(FTS_NAMEONLY); 539 instr = BNAMES; 540 } else 541 instr = BCHILD; 542 543 /* 544 * If using chdir on a relative path and called BEFORE fts_read does 545 * its chdir to the root of a traversal, we can lose -- we need to 546 * chdir into the subdirectory, and we don't know where the current 547 * directory is, so we can't get back so that the upcoming chdir by 548 * fts_read will work. 549 */ 550 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 551 ISSET(FTS_NOCHDIR)) 552 return (sp->fts_child = fts_build(sp, instr)); 553 554 if ((fd = open(".", O_RDONLY, 0)) < 0) 555 return (NULL); 556 sp->fts_child = fts_build(sp, instr); 557 if (fchdir(fd)) 558 return (NULL); 559 (void)close(fd); 560 return (sp->fts_child); 561} 562 563/* 564 * This is the tricky part -- do not casually change *anything* in here. The 565 * idea is to build the linked list of entries that are used by fts_children 566 * and fts_read. There are lots of special cases. 567 * 568 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 569 * set and it's a physical walk (so that symbolic links can't be directories), 570 * we can do things quickly. First, if it's a 4.4BSD file system, the type 571 * of the file is in the directory entry. Otherwise, we assume that the number 572 * of subdirectories in a node is equal to the number of links to the parent. 573 * The former skips all stat calls. The latter skips stat calls in any leaf 574 * directories and for any files after the subdirectories in the directory have 575 * been found, cutting the stat calls by about 2/3. 576 */ 577static FTSENT * 578fts_build(sp, type) 579 register FTS *sp; 580 int type; 581{ 582 register struct dirent *dp; 583 register FTSENT *p, *head; 584 register int nitems; 585 FTSENT *cur, *tail; 586 DIR *dirp; 587 void *adjaddr; 588 int cderrno, descend, len, level, maxlen, nlinks, oflag, saved_errno, 589 nostat = 0; 590 char *cp = NULL; /* pacify gcc */ 591 592 /* Set current node pointer. */ 593 cur = sp->fts_cur; 594 595 /* 596 * Open the directory for reading. If this fails, we're done. 597 * If being called from fts_read, set the fts_info field. 598 */ 599#ifdef FTS_WHITEOUT 600 if (ISSET(FTS_WHITEOUT)) 601 oflag = DTF_NODUP|DTF_REWIND; 602 else 603 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND; 604#else 605#define __opendir2(path, flag) opendir(path) 606#endif 607 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 608 if (type == BREAD) { 609 cur->fts_info = FTS_DNR; 610 cur->fts_errno = errno; 611 } 612 return (NULL); 613 } 614 615 /* 616 * Nlinks is the number of possible entries of type directory in the 617 * directory if we're cheating on stat calls, 0 if we're not doing 618 * any stat calls at all, -1 if we're doing stats on everything. 619 */ 620 if (type == BNAMES) 621 nlinks = 0; 622 else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) { 623 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 624 nostat = 1; 625 } else { 626 nlinks = -1; 627 nostat = 0; 628 } 629 630#ifdef notdef 631 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 632 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 633 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 634#endif 635 /* 636 * If we're going to need to stat anything or we want to descend 637 * and stay in the directory, chdir. If this fails we keep going, 638 * but set a flag so we don't chdir after the post-order visit. 639 * We won't be able to stat anything, but we can still return the 640 * names themselves. Note, that since fts_read won't be able to 641 * chdir into the directory, it will have to return different path 642 * names than before, i.e. "a/b" instead of "b". Since the node 643 * has already been visited in pre-order, have to wait until the 644 * post-order visit to return the error. There is a special case 645 * here, if there was nothing to stat then it's not an error to 646 * not be able to stat. This is all fairly nasty. If a program 647 * needed sorted entries or stat information, they had better be 648 * checking FTS_NS on the returned nodes. 649 */ 650 cderrno = 0; 651 if (nlinks || type == BREAD) 652 if (FCHDIR(sp, dirfd(dirp))) { 653 if (nlinks && type == BREAD) 654 cur->fts_errno = errno; 655 cur->fts_flags |= FTS_DONTCHDIR; 656 descend = 0; 657 cderrno = errno; 658 } else 659 descend = 1; 660 else 661 descend = 0; 662 663 /* 664 * Figure out the max file name length that can be stored in the 665 * current path -- the inner loop allocates more path as necessary. 666 * We really wouldn't have to do the maxlen calculations here, we 667 * could do them in fts_read before returning the path, but it's a 668 * lot easier here since the length is part of the dirent structure. 669 * 670 * If not changing directories set a pointer so that can just append 671 * each new name into the path. 672 */ 673 maxlen = sp->fts_pathlen - cur->fts_pathlen - 1; 674 len = NAPPEND(cur); 675 if (ISSET(FTS_NOCHDIR)) { 676 cp = sp->fts_path + len; 677 *cp++ = '/'; 678 } 679 680 level = cur->fts_level + 1; 681 682 /* Read the directory, attaching each entry to the `link' pointer. */ 683 adjaddr = NULL; 684 for (head = tail = NULL, nitems = 0; (dp = readdir(dirp)) != NULL;) { 685 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 686 continue; 687 688 if ((p = fts_alloc(sp, dp->d_name, (int)dp->d_namlen)) == NULL) 689 goto mem1; 690 if (dp->d_namlen > maxlen) { 691 if (fts_palloc(sp, (size_t)dp->d_namlen)) { 692 /* 693 * No more memory for path or structures. Save 694 * errno, free up the current structure and the 695 * structures already allocated. 696 */ 697mem1: saved_errno = errno; 698 if (p) 699 free(p); 700 fts_lfree(head); 701 (void)closedir(dirp); 702 errno = saved_errno; 703 cur->fts_info = FTS_ERR; 704 SET(FTS_STOP); 705 return (NULL); 706 } 707 adjaddr = sp->fts_path; 708 maxlen = sp->fts_pathlen - sp->fts_cur->fts_pathlen - 1; 709 } 710 711 p->fts_pathlen = len + dp->d_namlen + 1; 712 p->fts_parent = sp->fts_cur; 713 p->fts_level = level; 714 715#ifdef FTS_WHITEOUT 716 if (dp->d_type == DT_WHT) 717 p->fts_flags |= FTS_ISW; 718#endif 719 720 if (cderrno) { 721 if (nlinks) { 722 p->fts_info = FTS_NS; 723 p->fts_errno = cderrno; 724 } else 725 p->fts_info = FTS_NSOK; 726 p->fts_accpath = cur->fts_accpath; 727 } else if (nlinks == 0 728#ifdef DT_DIR 729 || (nostat && 730 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN) 731#endif 732 ) { 733 p->fts_accpath = 734 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 735 p->fts_info = FTS_NSOK; 736 } else { 737 /* Build a file name for fts_stat to stat. */ 738 if (ISSET(FTS_NOCHDIR)) { 739 p->fts_accpath = p->fts_path; 740 memmove(cp, p->fts_name, p->fts_namelen + 1); 741 } else 742 p->fts_accpath = p->fts_name; 743 /* Stat it. */ 744 p->fts_info = fts_stat(sp, p, 0); 745 746 /* Decrement link count if applicable. */ 747 if (nlinks > 0 && (p->fts_info == FTS_D || 748 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 749 --nlinks; 750 } 751 752 /* We walk in directory order so "ls -f" doesn't get upset. */ 753 p->fts_link = NULL; 754 if (head == NULL) 755 head = tail = p; 756 else { 757 tail->fts_link = p; 758 tail = p; 759 } 760 ++nitems; 761 } 762 (void)closedir(dirp); 763 764 /* 765 * If had to realloc the path, adjust the addresses for the rest 766 * of the tree. 767 */ 768 if (adjaddr) 769 fts_padjust(sp, adjaddr); 770 771 /* 772 * If not changing directories, reset the path back to original 773 * state. 774 */ 775 if (ISSET(FTS_NOCHDIR)) { 776 if (cp - 1 > sp->fts_path) 777 --cp; 778 *cp = '\0'; 779 } 780 781 /* 782 * If descended after called from fts_children or after called from 783 * fts_read and nothing found, get back. At the root level we use 784 * the saved fd; if one of fts_open()'s arguments is a relative path 785 * to an empty directory, we wind up here with no other way back. If 786 * can't get back, we're done. 787 */ 788 if (descend && (type == BCHILD || !nitems) && 789 (cur->fts_level == FTS_ROOTLEVEL ? 790 FCHDIR(sp, sp->fts_rfd) : CHDIR(sp, ".."))) { 791 cur->fts_info = FTS_ERR; 792 SET(FTS_STOP); 793 return (NULL); 794 } 795 796 /* If didn't find anything, return NULL. */ 797 if (!nitems) { 798 if (type == BREAD) 799 cur->fts_info = FTS_DP; 800 return (NULL); 801 } 802 803 /* Sort the entries. */ 804 if (sp->fts_compar && nitems > 1) 805 head = fts_sort(sp, head, nitems); 806 return (head); 807} 808 809static u_short 810fts_stat(sp, p, follow) 811 FTS *sp; 812 register FTSENT *p; 813 int follow; 814{ 815 register FTSENT *t; 816 register dev_t dev; 817 register ino_t ino; 818 struct stat *sbp, sb; 819 int saved_errno; 820 821 /* If user needs stat info, stat buffer already allocated. */ 822 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 823 824#ifdef FTS_WHITEOUT 825 /* check for whiteout */ 826 if (p->fts_flags & FTS_ISW) { 827 if (sbp != &sb) { 828 memset(sbp, '\0', sizeof (*sbp)); 829 sbp->st_mode = S_IFWHT; 830 } 831 return (FTS_W); 832 } 833#endif 834 835 /* 836 * If doing a logical walk, or application requested FTS_FOLLOW, do 837 * a stat(2). If that fails, check for a non-existent symlink. If 838 * fail, set the errno from the stat call. 839 */ 840 if (ISSET(FTS_LOGICAL) || follow) { 841 if (stat(p->fts_accpath, sbp)) { 842 saved_errno = errno; 843 if (!lstat(p->fts_accpath, sbp)) { 844 errno = 0; 845 return (FTS_SLNONE); 846 } 847 p->fts_errno = saved_errno; 848 goto err; 849 } 850 } else if (lstat(p->fts_accpath, sbp)) { 851 p->fts_errno = errno; 852err: memset(sbp, 0, sizeof(struct stat)); 853 return (FTS_NS); 854 } 855 856 if (S_ISDIR(sbp->st_mode)) { 857 /* 858 * Set the device/inode. Used to find cycles and check for 859 * crossing mount points. Also remember the link count, used 860 * in fts_build to limit the number of stat calls. It is 861 * understood that these fields are only referenced if fts_info 862 * is set to FTS_D. 863 */ 864 dev = p->fts_dev = sbp->st_dev; 865 ino = p->fts_ino = sbp->st_ino; 866 p->fts_nlink = sbp->st_nlink; 867 868 if (ISDOT(p->fts_name)) 869 return (FTS_DOT); 870 871 /* 872 * Cycle detection is done by brute force when the directory 873 * is first encountered. If the tree gets deep enough or the 874 * number of symbolic links to directories is high enough, 875 * something faster might be worthwhile. 876 */ 877 for (t = p->fts_parent; 878 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 879 if (ino == t->fts_ino && dev == t->fts_dev) { 880 p->fts_cycle = t; 881 return (FTS_DC); 882 } 883 return (FTS_D); 884 } 885 if (S_ISLNK(sbp->st_mode)) 886 return (FTS_SL); 887 if (S_ISREG(sbp->st_mode)) 888 return (FTS_F); 889 return (FTS_DEFAULT); 890} 891 892static FTSENT * 893fts_sort(sp, head, nitems) 894 FTS *sp; 895 FTSENT *head; 896 register int nitems; 897{ 898 register FTSENT **ap, *p; 899 900 /* 901 * Construct an array of pointers to the structures and call qsort(3). 902 * Reassemble the array in the order returned by qsort. If unable to 903 * sort for memory reasons, return the directory entries in their 904 * current order. Allocate enough space for the current needs plus 905 * 40 so don't realloc one entry at a time. 906 */ 907 if (nitems > sp->fts_nitems) { 908 sp->fts_nitems = nitems + 40; 909 if ((sp->fts_array = realloc(sp->fts_array, 910 (size_t)(sp->fts_nitems * sizeof(FTSENT *)))) == NULL) { 911 sp->fts_nitems = 0; 912 return (head); 913 } 914 } 915 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 916 *ap++ = p; 917 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), sp->fts_compar); 918 for (head = *(ap = sp->fts_array); --nitems; ++ap) 919 ap[0]->fts_link = ap[1]; 920 ap[0]->fts_link = NULL; 921 return (head); 922} 923 924static FTSENT * 925fts_alloc(sp, name, namelen) 926 FTS *sp; 927 char *name; 928 register int namelen; 929{ 930 register FTSENT *p; 931 size_t len; 932 933 /* 934 * The file name is a variable length array and no stat structure is 935 * necessary if the user has set the nostat bit. Allocate the FTSENT 936 * structure, the file name and the stat structure in one chunk, but 937 * be careful that the stat structure is reasonably aligned. Since the 938 * fts_name field is declared to be of size 1, the fts_name pointer is 939 * namelen + 2 before the first possible address of the stat structure. 940 */ 941 len = sizeof(FTSENT) + namelen; 942 if (!ISSET(FTS_NOSTAT)) 943 len += sizeof(struct stat) + ALIGNBYTES; 944 if ((p = malloc(len)) == NULL) 945 return (NULL); 946 947 /* Copy the name, then append the trailing NULL. */ 948 memmove(p->fts_name, name, namelen); 949 p->fts_name[namelen] = '\0'; 950 951 if (!ISSET(FTS_NOSTAT)) 952 p->fts_statp = (struct stat *)ALIGN(p->fts_name + namelen + 2); 953 p->fts_namelen = namelen; 954 p->fts_path = sp->fts_path; 955 p->fts_errno = 0; 956 p->fts_flags = 0; 957 p->fts_instr = FTS_NOINSTR; 958 p->fts_number = 0; 959 p->fts_pointer = NULL; 960 return (p); 961} 962 963static void 964fts_lfree(head) 965 register FTSENT *head; 966{ 967 register FTSENT *p; 968 969 /* Free a linked list of structures. */ 970 while ((p = head) != NULL) { 971 head = head->fts_link; 972 free(p); 973 } 974} 975 976/* 977 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 978 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 979 * though the kernel won't resolve them. Add the size (not just what's needed) 980 * plus 256 bytes so don't realloc the path 2 bytes at a time. 981 */ 982static int 983fts_palloc(sp, more) 984 FTS *sp; 985 size_t more; 986{ 987 sp->fts_pathlen += more + 256; 988 sp->fts_path = realloc(sp->fts_path, (size_t)sp->fts_pathlen); 989 return (sp->fts_path == NULL); 990} 991 992/* 993 * When the path is realloc'd, have to fix all of the pointers in structures 994 * already returned. 995 */ 996static void 997fts_padjust(sp, addr) 998 FTS *sp; 999 void *addr; 1000{ 1001 FTSENT *p; 1002 1003#define ADJUST(p) { \ 1004 (p)->fts_accpath = \ 1005 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \ 1006 (p)->fts_path = addr; \ 1007} 1008 /* Adjust the current set of children. */ 1009 for (p = sp->fts_child; p; p = p->fts_link) 1010 ADJUST(p); 1011 1012 /* Adjust the rest of the tree. */ 1013 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 1014 ADJUST(p); 1015 p = p->fts_link ? p->fts_link : p->fts_parent; 1016 } 1017} 1018 1019static size_t 1020fts_maxarglen(argv) 1021 char * const *argv; 1022{ 1023 size_t len, max; 1024 1025 for (max = 0; *argv; ++argv) 1026 if ((len = strlen(*argv)) > max) 1027 max = len; 1028 return (max); 1029} 1030