fts.c revision 1.17
1/* $NetBSD: fts.c,v 1.17 1997/10/07 23:02:17 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 1.17 1997/10/07 23:02:17 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 */ 143 if ((*argv)[len-1] == '/') 144 len--; 145 146 p = fts_alloc(sp, *argv, len); 147 p->fts_level = FTS_ROOTLEVEL; 148 p->fts_parent = parent; 149 p->fts_accpath = p->fts_name; 150 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 151 152 /* Command-line "." and ".." are real directories. */ 153 if (p->fts_info == FTS_DOT) 154 p->fts_info = FTS_D; 155 156 /* 157 * If comparison routine supplied, traverse in sorted 158 * order; otherwise traverse in the order specified. 159 */ 160 if (compar) { 161 p->fts_link = root; 162 root = p; 163 } else { 164 p->fts_link = NULL; 165 if (root == NULL) 166 tmp = root = p; 167 else { 168 tmp->fts_link = p; 169 tmp = p; 170 } 171 } 172 } 173 if (compar && nitems > 1) 174 root = fts_sort(sp, root, nitems); 175 176 /* 177 * Allocate a dummy pointer and make fts_read think that we've just 178 * finished the node before the root(s); set p->fts_info to FTS_INIT 179 * so that everything about the "current" node is ignored. 180 */ 181 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 182 goto mem3; 183 sp->fts_cur->fts_link = root; 184 sp->fts_cur->fts_info = FTS_INIT; 185 186 /* 187 * If using chdir(2), grab a file descriptor pointing to dot to insure 188 * that we can get back here; this could be avoided for some paths, 189 * but almost certainly not worth the effort. Slashes, symbolic links, 190 * and ".." are all fairly nasty problems. Note, if we can't get the 191 * descriptor we run anyway, just more slowly. 192 */ 193 if (!ISSET(FTS_NOCHDIR) && (sp->fts_rfd = open(".", O_RDONLY, 0)) < 0) 194 SET(FTS_NOCHDIR); 195 196 return (sp); 197 198mem3: fts_lfree(root); 199 free(parent); 200mem2: free(sp->fts_path); 201mem1: free(sp); 202 return (NULL); 203} 204 205static void 206fts_load(sp, p) 207 FTS *sp; 208 register FTSENT *p; 209{ 210 register int len; 211 register char *cp; 212 213 /* 214 * Load the stream structure for the next traversal. Since we don't 215 * actually enter the directory until after the preorder visit, set 216 * the fts_accpath field specially so the chdir gets done to the right 217 * place and the user can access the first node. From fts_open it's 218 * known that the path will fit. 219 */ 220 len = p->fts_pathlen = p->fts_namelen; 221 memmove(sp->fts_path, p->fts_name, len + 1); 222 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 223 len = strlen(++cp); 224 memmove(p->fts_name, cp, len + 1); 225 p->fts_namelen = len; 226 } 227 p->fts_accpath = p->fts_path = sp->fts_path; 228 sp->fts_dev = p->fts_dev; 229} 230 231int 232fts_close(sp) 233 FTS *sp; 234{ 235 register FTSENT *freep, *p; 236 int saved_errno = 0; /* pacify gcc */ 237 238 /* 239 * This still works if we haven't read anything -- the dummy structure 240 * points to the root list, so we step through to the end of the root 241 * list which has a valid parent pointer. 242 */ 243 if (sp->fts_cur) { 244 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 245 freep = p; 246 p = p->fts_link ? p->fts_link : p->fts_parent; 247 free(freep); 248 } 249 free(p); 250 } 251 252 /* Free up child linked list, sort array, path buffer. */ 253 if (sp->fts_child) 254 fts_lfree(sp->fts_child); 255 if (sp->fts_array) 256 free(sp->fts_array); 257 free(sp->fts_path); 258 259 /* Return to original directory, save errno if necessary. */ 260 if (!ISSET(FTS_NOCHDIR)) { 261 saved_errno = fchdir(sp->fts_rfd) ? errno : 0; 262 (void)close(sp->fts_rfd); 263 } 264 265 /* Free up the stream pointer. */ 266 free(sp); 267 268 /* Set errno and return. */ 269 if (!ISSET(FTS_NOCHDIR) && saved_errno) { 270 errno = saved_errno; 271 return (-1); 272 } 273 return (0); 274} 275 276FTSENT * 277fts_read(sp) 278 register FTS *sp; 279{ 280 register FTSENT *p, *tmp; 281 register int instr; 282 register char *t; 283 int saved_errno; 284 285 /* If finished or unrecoverable error, return NULL. */ 286 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 287 return (NULL); 288 289 /* Set current node pointer. */ 290 p = sp->fts_cur; 291 292 /* Save and zero out user instructions. */ 293 instr = p->fts_instr; 294 p->fts_instr = FTS_NOINSTR; 295 296 /* Any type of file may be re-visited; re-stat and re-turn. */ 297 if (instr == FTS_AGAIN) { 298 p->fts_info = fts_stat(sp, p, 0); 299 return (p); 300 } 301 302 /* 303 * Following a symlink -- SLNONE test allows application to see 304 * SLNONE and recover. If indirecting through a symlink, have 305 * keep a pointer to current location. If unable to get that 306 * pointer, follow fails. 307 */ 308 if (instr == FTS_FOLLOW && 309 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 310 p->fts_info = fts_stat(sp, p, 1); 311 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) 312 if ((p->fts_symfd = open(".", O_RDONLY, 0)) < 0) { 313 p->fts_errno = errno; 314 p->fts_info = FTS_ERR; 315 } else 316 p->fts_flags |= FTS_SYMFOLLOW; 317 return (p); 318 } 319 320 /* Directory in pre-order. */ 321 if (p->fts_info == FTS_D) { 322 /* If skipped or crossed mount point, do post-order visit. */ 323 if (instr == FTS_SKIP || 324 (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) { 325 if (p->fts_flags & FTS_SYMFOLLOW) 326 (void)close(p->fts_symfd); 327 if (sp->fts_child) { 328 fts_lfree(sp->fts_child); 329 sp->fts_child = NULL; 330 } 331 p->fts_info = FTS_DP; 332 return (p); 333 } 334 335 /* Rebuild if only read the names and now traversing. */ 336 if (sp->fts_child && ISSET(FTS_NAMEONLY)) { 337 CLR(FTS_NAMEONLY); 338 fts_lfree(sp->fts_child); 339 sp->fts_child = NULL; 340 } 341 342 /* 343 * Cd to the subdirectory. 344 * 345 * If have already read and now fail to chdir, whack the list 346 * to make the names come out right, and set the parent errno 347 * so the application will eventually get an error condition. 348 * Set the FTS_DONTCHDIR flag so that when we logically change 349 * directories back to the parent we don't do a chdir. 350 * 351 * If haven't read do so. If the read fails, fts_build sets 352 * FTS_STOP or the fts_info field of the node. 353 */ 354 if (sp->fts_child) { 355 if (CHDIR(sp, p->fts_accpath)) { 356 p->fts_errno = errno; 357 p->fts_flags |= FTS_DONTCHDIR; 358 for (p = sp->fts_child; p; p = p->fts_link) 359 p->fts_accpath = 360 p->fts_parent->fts_accpath; 361 } 362 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 363 if (ISSET(FTS_STOP)) 364 return (NULL); 365 return (p); 366 } 367 p = sp->fts_child; 368 sp->fts_child = NULL; 369 goto name; 370 } 371 372 /* Move to the next node on this level. */ 373next: tmp = p; 374 if ((p = p->fts_link) != NULL) { 375 free(tmp); 376 377 /* 378 * If reached the top, return to the original directory, and 379 * load the paths for the next root. 380 */ 381 if (p->fts_level == FTS_ROOTLEVEL) { 382 if (!ISSET(FTS_NOCHDIR) && FCHDIR(sp, sp->fts_rfd)) { 383 SET(FTS_STOP); 384 return (NULL); 385 } 386 fts_load(sp, p); 387 return (sp->fts_cur = p); 388 } 389 390 /* 391 * User may have called fts_set on the node. If skipped, 392 * ignore. If followed, get a file descriptor so we can 393 * get back if necessary. 394 */ 395 if (p->fts_instr == FTS_SKIP) 396 goto next; 397 if (p->fts_instr == FTS_FOLLOW) { 398 p->fts_info = fts_stat(sp, p, 1); 399 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) 400 if ((p->fts_symfd = 401 open(".", O_RDONLY, 0)) < 0) { 402 p->fts_errno = errno; 403 p->fts_info = FTS_ERR; 404 } else 405 p->fts_flags |= FTS_SYMFOLLOW; 406 p->fts_instr = FTS_NOINSTR; 407 } 408 409name: t = sp->fts_path + p->fts_parent->fts_pathlen; 410 *t++ = '/'; 411 memmove(t, p->fts_name, p->fts_namelen + 1); 412 return (sp->fts_cur = p); 413 } 414 415 /* Move up to the parent node. */ 416 p = tmp->fts_parent; 417 free(tmp); 418 419 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 420 /* 421 * Done; free everything up and set errno to 0 so the user 422 * can distinguish between error and EOF. 423 */ 424 free(p); 425 errno = 0; 426 return (sp->fts_cur = NULL); 427 } 428 429 /* Nul terminate the pathname. */ 430 sp->fts_path[p->fts_pathlen] = '\0'; 431 432 /* 433 * Return to the parent directory. If at a root node or came through 434 * a symlink, go back through the file descriptor. Otherwise, cd up 435 * one directory. 436 */ 437 if (p->fts_level == FTS_ROOTLEVEL) { 438 if (!ISSET(FTS_NOCHDIR) && FCHDIR(sp, sp->fts_rfd)) { 439 SET(FTS_STOP); 440 return (NULL); 441 } 442 } else if (p->fts_flags & FTS_SYMFOLLOW) { 443 if (FCHDIR(sp, p->fts_symfd)) { 444 saved_errno = errno; 445 (void)close(p->fts_symfd); 446 errno = saved_errno; 447 SET(FTS_STOP); 448 return (NULL); 449 } 450 (void)close(p->fts_symfd); 451 } else if (!(p->fts_flags & FTS_DONTCHDIR)) { 452 if (CHDIR(sp, "..")) { 453 SET(FTS_STOP); 454 return (NULL); 455 } 456 } 457 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 458 return (sp->fts_cur = p); 459} 460 461/* 462 * Fts_set takes the stream as an argument although it's not used in this 463 * implementation; it would be necessary if anyone wanted to add global 464 * semantics to fts using fts_set. An error return is allowed for similar 465 * reasons. 466 */ 467/* ARGSUSED */ 468int 469fts_set(sp, p, instr) 470 FTS *sp; 471 FTSENT *p; 472 int instr; 473{ 474 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW && 475 instr != FTS_NOINSTR && instr != FTS_SKIP) { 476 errno = EINVAL; 477 return (1); 478 } 479 p->fts_instr = instr; 480 return (0); 481} 482 483FTSENT * 484fts_children(sp, instr) 485 register FTS *sp; 486 int instr; 487{ 488 register FTSENT *p; 489 int fd; 490 491 if (instr && instr != FTS_NAMEONLY) { 492 errno = EINVAL; 493 return (NULL); 494 } 495 496 /* Set current node pointer. */ 497 p = sp->fts_cur; 498 499 /* 500 * Errno set to 0 so user can distinguish empty directory from 501 * an error. 502 */ 503 errno = 0; 504 505 /* Fatal errors stop here. */ 506 if (ISSET(FTS_STOP)) 507 return (NULL); 508 509 /* Return logical hierarchy of user's arguments. */ 510 if (p->fts_info == FTS_INIT) 511 return (p->fts_link); 512 513 /* 514 * If not a directory being visited in pre-order, stop here. Could 515 * allow FTS_DNR, assuming the user has fixed the problem, but the 516 * same effect is available with FTS_AGAIN. 517 */ 518 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 519 return (NULL); 520 521 /* Free up any previous child list. */ 522 if (sp->fts_child) 523 fts_lfree(sp->fts_child); 524 525 if (instr == FTS_NAMEONLY) { 526 SET(FTS_NAMEONLY); 527 instr = BNAMES; 528 } else 529 instr = BCHILD; 530 531 /* 532 * If using chdir on a relative path and called BEFORE fts_read does 533 * its chdir to the root of a traversal, we can lose -- we need to 534 * chdir into the subdirectory, and we don't know where the current 535 * directory is, so we can't get back so that the upcoming chdir by 536 * fts_read will work. 537 */ 538 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 539 ISSET(FTS_NOCHDIR)) 540 return (sp->fts_child = fts_build(sp, instr)); 541 542 if ((fd = open(".", O_RDONLY, 0)) < 0) 543 return (NULL); 544 sp->fts_child = fts_build(sp, instr); 545 if (fchdir(fd)) 546 return (NULL); 547 (void)close(fd); 548 return (sp->fts_child); 549} 550 551/* 552 * This is the tricky part -- do not casually change *anything* in here. The 553 * idea is to build the linked list of entries that are used by fts_children 554 * and fts_read. There are lots of special cases. 555 * 556 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 557 * set and it's a physical walk (so that symbolic links can't be directories), 558 * we can do things quickly. First, if it's a 4.4BSD file system, the type 559 * of the file is in the directory entry. Otherwise, we assume that the number 560 * of subdirectories in a node is equal to the number of links to the parent. 561 * The former skips all stat calls. The latter skips stat calls in any leaf 562 * directories and for any files after the subdirectories in the directory have 563 * been found, cutting the stat calls by about 2/3. 564 */ 565static FTSENT * 566fts_build(sp, type) 567 register FTS *sp; 568 int type; 569{ 570 register struct dirent *dp; 571 register FTSENT *p, *head; 572 register int nitems; 573 FTSENT *cur, *tail; 574 DIR *dirp; 575 void *adjaddr; 576 int cderrno, descend, len, level, maxlen, nlinks, oflag, saved_errno, 577 nostat = 0; 578 char *cp = NULL; /* pacify gcc */ 579 580 /* Set current node pointer. */ 581 cur = sp->fts_cur; 582 583 /* 584 * Open the directory for reading. If this fails, we're done. 585 * If being called from fts_read, set the fts_info field. 586 */ 587#ifdef FTS_WHITEOUT 588 if (ISSET(FTS_WHITEOUT)) 589 oflag = DTF_NODUP|DTF_REWIND; 590 else 591 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND; 592#else 593#define __opendir2(path, flag) opendir(path) 594#endif 595 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 596 if (type == BREAD) { 597 cur->fts_info = FTS_DNR; 598 cur->fts_errno = errno; 599 } 600 return (NULL); 601 } 602 603 /* 604 * Nlinks is the number of possible entries of type directory in the 605 * directory if we're cheating on stat calls, 0 if we're not doing 606 * any stat calls at all, -1 if we're doing stats on everything. 607 */ 608 if (type == BNAMES) 609 nlinks = 0; 610 else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) { 611 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 612 nostat = 1; 613 } else { 614 nlinks = -1; 615 nostat = 0; 616 } 617 618#ifdef notdef 619 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 620 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 621 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 622#endif 623 /* 624 * If we're going to need to stat anything or we want to descend 625 * and stay in the directory, chdir. If this fails we keep going, 626 * but set a flag so we don't chdir after the post-order visit. 627 * We won't be able to stat anything, but we can still return the 628 * names themselves. Note, that since fts_read won't be able to 629 * chdir into the directory, it will have to return different path 630 * names than before, i.e. "a/b" instead of "b". Since the node 631 * has already been visited in pre-order, have to wait until the 632 * post-order visit to return the error. There is a special case 633 * here, if there was nothing to stat then it's not an error to 634 * not be able to stat. This is all fairly nasty. If a program 635 * needed sorted entries or stat information, they had better be 636 * checking FTS_NS on the returned nodes. 637 */ 638 cderrno = 0; 639 if (nlinks || type == BREAD) 640 if (FCHDIR(sp, dirfd(dirp))) { 641 if (nlinks && type == BREAD) 642 cur->fts_errno = errno; 643 cur->fts_flags |= FTS_DONTCHDIR; 644 descend = 0; 645 cderrno = errno; 646 } else 647 descend = 1; 648 else 649 descend = 0; 650 651 /* 652 * Figure out the max file name length that can be stored in the 653 * current path -- the inner loop allocates more path as necessary. 654 * We really wouldn't have to do the maxlen calculations here, we 655 * could do them in fts_read before returning the path, but it's a 656 * lot easier here since the length is part of the dirent structure. 657 * 658 * If not changing directories set a pointer so that can just append 659 * each new name into the path. 660 */ 661 maxlen = sp->fts_pathlen - cur->fts_pathlen - 1; 662 len = cur->fts_pathlen; 663 if (ISSET(FTS_NOCHDIR)) { 664 cp = sp->fts_path + len; 665 *cp++ = '/'; 666 } 667 668 level = cur->fts_level + 1; 669 670 /* Read the directory, attaching each entry to the `link' pointer. */ 671 adjaddr = NULL; 672 for (head = tail = NULL, nitems = 0; (dp = readdir(dirp)) != NULL;) { 673 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 674 continue; 675 676 if ((p = fts_alloc(sp, dp->d_name, (int)dp->d_namlen)) == NULL) 677 goto mem1; 678 if (dp->d_namlen > maxlen) { 679 if (fts_palloc(sp, (size_t)dp->d_namlen)) { 680 /* 681 * No more memory for path or structures. Save 682 * errno, free up the current structure and the 683 * structures already allocated. 684 */ 685mem1: saved_errno = errno; 686 if (p) 687 free(p); 688 fts_lfree(head); 689 (void)closedir(dirp); 690 errno = saved_errno; 691 cur->fts_info = FTS_ERR; 692 SET(FTS_STOP); 693 return (NULL); 694 } 695 adjaddr = sp->fts_path; 696 maxlen = sp->fts_pathlen - sp->fts_cur->fts_pathlen - 1; 697 } 698 699 p->fts_pathlen = len + dp->d_namlen + 1; 700 p->fts_parent = sp->fts_cur; 701 p->fts_level = level; 702 703#ifdef FTS_WHITEOUT 704 if (dp->d_type == DT_WHT) 705 p->fts_flags |= FTS_ISW; 706#endif 707 708 if (cderrno) { 709 if (nlinks) { 710 p->fts_info = FTS_NS; 711 p->fts_errno = cderrno; 712 } else 713 p->fts_info = FTS_NSOK; 714 p->fts_accpath = cur->fts_accpath; 715 } else if (nlinks == 0 716#ifdef DT_DIR 717 || (nostat && 718 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN) 719#endif 720 ) { 721 p->fts_accpath = 722 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 723 p->fts_info = FTS_NSOK; 724 } else { 725 /* Build a file name for fts_stat to stat. */ 726 if (ISSET(FTS_NOCHDIR)) { 727 p->fts_accpath = p->fts_path; 728 memmove(cp, p->fts_name, p->fts_namelen + 1); 729 } else 730 p->fts_accpath = p->fts_name; 731 /* Stat it. */ 732 p->fts_info = fts_stat(sp, p, 0); 733 734 /* Decrement link count if applicable. */ 735 if (nlinks > 0 && (p->fts_info == FTS_D || 736 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 737 --nlinks; 738 } 739 740 /* We walk in directory order so "ls -f" doesn't get upset. */ 741 p->fts_link = NULL; 742 if (head == NULL) 743 head = tail = p; 744 else { 745 tail->fts_link = p; 746 tail = p; 747 } 748 ++nitems; 749 } 750 (void)closedir(dirp); 751 752 /* 753 * If had to realloc the path, adjust the addresses for the rest 754 * of the tree. 755 */ 756 if (adjaddr) 757 fts_padjust(sp, adjaddr); 758 759 /* 760 * If not changing directories, reset the path back to original 761 * state. 762 */ 763 if (ISSET(FTS_NOCHDIR)) { 764 if (cp - 1 > sp->fts_path) 765 --cp; 766 *cp = '\0'; 767 } 768 769 /* 770 * If descended after called from fts_children or after called from 771 * fts_read and nothing found, get back. At the root level we use 772 * the saved fd; if one of fts_open()'s arguments is a relative path 773 * to an empty directory, we wind up here with no other way back. If 774 * can't get back, we're done. 775 */ 776 if (descend && (type == BCHILD || !nitems) && 777 (cur->fts_level == FTS_ROOTLEVEL ? 778 FCHDIR(sp, sp->fts_rfd) : CHDIR(sp, ".."))) { 779 cur->fts_info = FTS_ERR; 780 SET(FTS_STOP); 781 return (NULL); 782 } 783 784 /* If didn't find anything, return NULL. */ 785 if (!nitems) { 786 if (type == BREAD) 787 cur->fts_info = FTS_DP; 788 return (NULL); 789 } 790 791 /* Sort the entries. */ 792 if (sp->fts_compar && nitems > 1) 793 head = fts_sort(sp, head, nitems); 794 return (head); 795} 796 797static u_short 798fts_stat(sp, p, follow) 799 FTS *sp; 800 register FTSENT *p; 801 int follow; 802{ 803 register FTSENT *t; 804 register dev_t dev; 805 register ino_t ino; 806 struct stat *sbp, sb; 807 int saved_errno; 808 809 /* If user needs stat info, stat buffer already allocated. */ 810 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 811 812#ifdef FTS_WHITEOUT 813 /* check for whiteout */ 814 if (p->fts_flags & FTS_ISW) { 815 if (sbp != &sb) { 816 memset(sbp, '\0', sizeof (*sbp)); 817 sbp->st_mode = S_IFWHT; 818 } 819 return (FTS_W); 820 } 821#endif 822 823 /* 824 * If doing a logical walk, or application requested FTS_FOLLOW, do 825 * a stat(2). If that fails, check for a non-existent symlink. If 826 * fail, set the errno from the stat call. 827 */ 828 if (ISSET(FTS_LOGICAL) || follow) { 829 if (stat(p->fts_accpath, sbp)) { 830 saved_errno = errno; 831 if (!lstat(p->fts_accpath, sbp)) { 832 errno = 0; 833 return (FTS_SLNONE); 834 } 835 p->fts_errno = saved_errno; 836 goto err; 837 } 838 } else if (lstat(p->fts_accpath, sbp)) { 839 p->fts_errno = errno; 840err: memset(sbp, 0, sizeof(struct stat)); 841 return (FTS_NS); 842 } 843 844 if (S_ISDIR(sbp->st_mode)) { 845 /* 846 * Set the device/inode. Used to find cycles and check for 847 * crossing mount points. Also remember the link count, used 848 * in fts_build to limit the number of stat calls. It is 849 * understood that these fields are only referenced if fts_info 850 * is set to FTS_D. 851 */ 852 dev = p->fts_dev = sbp->st_dev; 853 ino = p->fts_ino = sbp->st_ino; 854 p->fts_nlink = sbp->st_nlink; 855 856 if (ISDOT(p->fts_name)) 857 return (FTS_DOT); 858 859 /* 860 * Cycle detection is done by brute force when the directory 861 * is first encountered. If the tree gets deep enough or the 862 * number of symbolic links to directories is high enough, 863 * something faster might be worthwhile. 864 */ 865 for (t = p->fts_parent; 866 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 867 if (ino == t->fts_ino && dev == t->fts_dev) { 868 p->fts_cycle = t; 869 return (FTS_DC); 870 } 871 return (FTS_D); 872 } 873 if (S_ISLNK(sbp->st_mode)) 874 return (FTS_SL); 875 if (S_ISREG(sbp->st_mode)) 876 return (FTS_F); 877 return (FTS_DEFAULT); 878} 879 880static FTSENT * 881fts_sort(sp, head, nitems) 882 FTS *sp; 883 FTSENT *head; 884 register int nitems; 885{ 886 register FTSENT **ap, *p; 887 888 /* 889 * Construct an array of pointers to the structures and call qsort(3). 890 * Reassemble the array in the order returned by qsort. If unable to 891 * sort for memory reasons, return the directory entries in their 892 * current order. Allocate enough space for the current needs plus 893 * 40 so don't realloc one entry at a time. 894 */ 895 if (nitems > sp->fts_nitems) { 896 sp->fts_nitems = nitems + 40; 897 if ((sp->fts_array = realloc(sp->fts_array, 898 (size_t)(sp->fts_nitems * sizeof(FTSENT *)))) == NULL) { 899 sp->fts_nitems = 0; 900 return (head); 901 } 902 } 903 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 904 *ap++ = p; 905 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), sp->fts_compar); 906 for (head = *(ap = sp->fts_array); --nitems; ++ap) 907 ap[0]->fts_link = ap[1]; 908 ap[0]->fts_link = NULL; 909 return (head); 910} 911 912static FTSENT * 913fts_alloc(sp, name, namelen) 914 FTS *sp; 915 char *name; 916 register int namelen; 917{ 918 register FTSENT *p; 919 size_t len; 920 921 /* 922 * The file name is a variable length array and no stat structure is 923 * necessary if the user has set the nostat bit. Allocate the FTSENT 924 * structure, the file name and the stat structure in one chunk, but 925 * be careful that the stat structure is reasonably aligned. Since the 926 * fts_name field is declared to be of size 1, the fts_name pointer is 927 * namelen + 2 before the first possible address of the stat structure. 928 */ 929 len = sizeof(FTSENT) + namelen; 930 if (!ISSET(FTS_NOSTAT)) 931 len += sizeof(struct stat) + ALIGNBYTES; 932 if ((p = malloc(len)) == NULL) 933 return (NULL); 934 935 /* Copy the name, then append the trailing NULL. */ 936 memmove(p->fts_name, name, namelen); 937 p->fts_name[namelen] = '\0'; 938 939 if (!ISSET(FTS_NOSTAT)) 940 p->fts_statp = (struct stat *)ALIGN(p->fts_name + namelen + 2); 941 p->fts_namelen = namelen; 942 p->fts_path = sp->fts_path; 943 p->fts_errno = 0; 944 p->fts_flags = 0; 945 p->fts_instr = FTS_NOINSTR; 946 p->fts_number = 0; 947 p->fts_pointer = NULL; 948 return (p); 949} 950 951static void 952fts_lfree(head) 953 register FTSENT *head; 954{ 955 register FTSENT *p; 956 957 /* Free a linked list of structures. */ 958 while ((p = head) != NULL) { 959 head = head->fts_link; 960 free(p); 961 } 962} 963 964/* 965 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 966 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 967 * though the kernel won't resolve them. Add the size (not just what's needed) 968 * plus 256 bytes so don't realloc the path 2 bytes at a time. 969 */ 970static int 971fts_palloc(sp, more) 972 FTS *sp; 973 size_t more; 974{ 975 sp->fts_pathlen += more + 256; 976 sp->fts_path = realloc(sp->fts_path, (size_t)sp->fts_pathlen); 977 return (sp->fts_path == NULL); 978} 979 980/* 981 * When the path is realloc'd, have to fix all of the pointers in structures 982 * already returned. 983 */ 984static void 985fts_padjust(sp, addr) 986 FTS *sp; 987 void *addr; 988{ 989 FTSENT *p; 990 991#define ADJUST(p) { \ 992 (p)->fts_accpath = \ 993 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \ 994 (p)->fts_path = addr; \ 995} 996 /* Adjust the current set of children. */ 997 for (p = sp->fts_child; p; p = p->fts_link) 998 ADJUST(p); 999 1000 /* Adjust the rest of the tree. */ 1001 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 1002 ADJUST(p); 1003 p = p->fts_link ? p->fts_link : p->fts_parent; 1004 } 1005} 1006 1007static size_t 1008fts_maxarglen(argv) 1009 char * const *argv; 1010{ 1011 size_t len, max; 1012 1013 for (max = 0; *argv; ++argv) 1014 if ((len = strlen(*argv)) > max) 1015 max = len; 1016 return (max); 1017} 1018