fts.c revision 1.20
1/* $NetBSD: fts.c,v 1.20 1997/10/21 00:56:51 fvdl 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 8.6 (Berkeley) 8/14/94"; 40#else 41__RCSID("$NetBSD: fts.c,v 1.20 1997/10/21 00:56:51 fvdl 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#undef fts_children 58#undef fts_close 59#undef fts_open 60#undef fts_read 61#undef fts_set 62#undef stat 63#undef fstat 64#undef lstat 65 66#define FTSENT FTSENT12 67#define FTS FTS12 68 69#ifdef __weak_alias 70__weak_alias(fts_children,_fts_children); 71__weak_alias(fts_close,_fts_close); 72__weak_alias(fts_open,_fts_open); 73__weak_alias(fts_read,_fts_read); 74__weak_alias(fts_set,_fts_set); 75#endif 76 77static FTSENT *fts_alloc __P((FTS *, char *, int)); 78static FTSENT *fts_build __P((FTS *, int)); 79static void fts_lfree __P((FTSENT *)); 80static void fts_load __P((FTS *, FTSENT *)); 81static size_t fts_maxarglen __P((char * const *)); 82static void fts_padjust __P((FTS *, void *)); 83static int fts_palloc __P((FTS *, size_t)); 84static FTSENT *fts_sort __P((FTS *, FTSENT *, int)); 85static u_short fts_stat __P((FTS *, FTSENT *, int)); 86 87#define ISDOT(a) (a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2]))) 88 89#define CLR(opt) (sp->fts_options &= ~(opt)) 90#define ISSET(opt) (sp->fts_options & (opt)) 91#define SET(opt) (sp->fts_options |= (opt)) 92 93#define CHDIR(sp, path) (!ISSET(FTS_NOCHDIR) && chdir(path)) 94#define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) && fchdir(fd)) 95 96/* fts_build flags */ 97#define BCHILD 1 /* fts_children */ 98#define BNAMES 2 /* fts_children, names only */ 99#define BREAD 3 /* fts_read */ 100 101FTS * 102fts_open(argv, options, compar) 103 char * const *argv; 104 register int options; 105 int (*compar) __P((const FTSENT **, const FTSENT **)); 106{ 107 register FTS *sp; 108 register FTSENT *p, *root; 109 register int nitems; 110 FTSENT *parent, *tmp = NULL; /* pacify gcc */ 111 int len; 112 113 /* Options check. */ 114 if (options & ~FTS_OPTIONMASK) { 115 errno = EINVAL; 116 return (NULL); 117 } 118 119 /* Allocate/initialize the stream */ 120 if ((sp = malloc((u_int)sizeof(FTS))) == NULL) 121 return (NULL); 122 memset(sp, 0, sizeof(FTS)); 123 sp->fts_compar = compar; 124 sp->fts_options = options; 125 126 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 127 if (ISSET(FTS_LOGICAL)) 128 SET(FTS_NOCHDIR); 129 130 /* 131 * Start out with 1K of path space, and enough, in any case, 132 * to hold the user's paths. 133 */ 134 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN))) 135 goto mem1; 136 137 /* Allocate/initialize root's parent. */ 138 if ((parent = fts_alloc(sp, "", 0)) == NULL) 139 goto mem2; 140 parent->fts_level = FTS_ROOTPARENTLEVEL; 141 142 /* Allocate/initialize root(s). */ 143 for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) { 144 /* Don't allow zero-length paths. */ 145 if ((len = strlen(*argv)) == 0) { 146 errno = ENOENT; 147 goto mem3; 148 } 149 150 p = fts_alloc(sp, *argv, len); 151 p->fts_level = FTS_ROOTLEVEL; 152 p->fts_parent = parent; 153 p->fts_accpath = p->fts_name; 154 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 155 156 /* Command-line "." and ".." are real directories. */ 157 if (p->fts_info == FTS_DOT) 158 p->fts_info = FTS_D; 159 160 /* 161 * If comparison routine supplied, traverse in sorted 162 * order; otherwise traverse in the order specified. 163 */ 164 if (compar) { 165 p->fts_link = root; 166 root = p; 167 } else { 168 p->fts_link = NULL; 169 if (root == NULL) 170 tmp = root = p; 171 else { 172 tmp->fts_link = p; 173 tmp = p; 174 } 175 } 176 } 177 if (compar && nitems > 1) 178 root = fts_sort(sp, root, nitems); 179 180 /* 181 * Allocate a dummy pointer and make fts_read think that we've just 182 * finished the node before the root(s); set p->fts_info to FTS_INIT 183 * so that everything about the "current" node is ignored. 184 */ 185 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 186 goto mem3; 187 sp->fts_cur->fts_link = root; 188 sp->fts_cur->fts_info = FTS_INIT; 189 190 /* 191 * If using chdir(2), grab a file descriptor pointing to dot to insure 192 * that we can get back here; this could be avoided for some paths, 193 * but almost certainly not worth the effort. Slashes, symbolic links, 194 * and ".." are all fairly nasty problems. Note, if we can't get the 195 * descriptor we run anyway, just more slowly. 196 */ 197 if (!ISSET(FTS_NOCHDIR) && (sp->fts_rfd = open(".", O_RDONLY, 0)) < 0) 198 SET(FTS_NOCHDIR); 199 200 return (sp); 201 202mem3: fts_lfree(root); 203 free(parent); 204mem2: free(sp->fts_path); 205mem1: free(sp); 206 return (NULL); 207} 208 209static void 210fts_load(sp, p) 211 FTS *sp; 212 register FTSENT *p; 213{ 214 register int len; 215 register char *cp; 216 217 /* 218 * Load the stream structure for the next traversal. Since we don't 219 * actually enter the directory until after the preorder visit, set 220 * the fts_accpath field specially so the chdir gets done to the right 221 * place and the user can access the first node. From fts_open it's 222 * known that the path will fit. 223 */ 224 len = p->fts_pathlen = p->fts_namelen; 225 memmove(sp->fts_path, p->fts_name, len + 1); 226 if ((cp = strrchr(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 227 len = strlen(++cp); 228 memmove(p->fts_name, cp, len + 1); 229 p->fts_namelen = len; 230 } 231 p->fts_accpath = p->fts_path = sp->fts_path; 232 sp->fts_dev = p->fts_dev; 233} 234 235int 236fts_close(sp) 237 FTS *sp; 238{ 239 register FTSENT *freep, *p; 240 int saved_errno = 0; /* pacify gcc */ 241 242 /* 243 * This still works if we haven't read anything -- the dummy structure 244 * points to the root list, so we step through to the end of the root 245 * list which has a valid parent pointer. 246 */ 247 if (sp->fts_cur) { 248 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 249 freep = p; 250 p = p->fts_link ? p->fts_link : p->fts_parent; 251 free(freep); 252 } 253 free(p); 254 } 255 256 /* Free up child linked list, sort array, path buffer. */ 257 if (sp->fts_child) 258 fts_lfree(sp->fts_child); 259 if (sp->fts_array) 260 free(sp->fts_array); 261 free(sp->fts_path); 262 263 /* Return to original directory, save errno if necessary. */ 264 if (!ISSET(FTS_NOCHDIR)) { 265 saved_errno = fchdir(sp->fts_rfd) ? errno : 0; 266 (void)close(sp->fts_rfd); 267 } 268 269 /* Free up the stream pointer. */ 270 free(sp); 271 272 /* Set errno and return. */ 273 if (!ISSET(FTS_NOCHDIR) && saved_errno) { 274 errno = saved_errno; 275 return (-1); 276 } 277 return (0); 278} 279 280/* 281 * Special case a root of "/" so that slashes aren't appended which would 282 * cause paths to be written as "//foo". 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 char *cp = NULL; /* pacify gcc */ 590 591 /* Set current node pointer. */ 592 cur = sp->fts_cur; 593 594 /* 595 * Open the directory for reading. If this fails, we're done. 596 * If being called from fts_read, set the fts_info field. 597 */ 598#ifdef FTS_WHITEOUT 599 if (ISSET(FTS_WHITEOUT)) 600 oflag = DTF_NODUP|DTF_REWIND; 601 else 602 oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND; 603#else 604#define __opendir2(path, flag) opendir(path) 605#endif 606 if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) { 607 if (type == BREAD) { 608 cur->fts_info = FTS_DNR; 609 cur->fts_errno = errno; 610 } 611 return (NULL); 612 } 613 614 /* 615 * Nlinks is the number of possible entries of type directory in the 616 * directory if we're cheating on stat calls, 0 if we're not doing 617 * any stat calls at all, -1 if we're doing stats on everything. 618 */ 619 if (type == BNAMES) 620 nlinks = 0; 621 else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) 622 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 623 else 624 nlinks = -1; 625 626#ifdef notdef 627 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 628 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 629 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 630#endif 631 /* 632 * If we're going to need to stat anything or we want to descend 633 * and stay in the directory, chdir. If this fails we keep going, 634 * but set a flag so we don't chdir after the post-order visit. 635 * We won't be able to stat anything, but we can still return the 636 * names themselves. Note, that since fts_read won't be able to 637 * chdir into the directory, it will have to return different path 638 * names than before, i.e. "a/b" instead of "b". Since the node 639 * has already been visited in pre-order, have to wait until the 640 * post-order visit to return the error. There is a special case 641 * here, if there was nothing to stat then it's not an error to 642 * not be able to stat. This is all fairly nasty. If a program 643 * needed sorted entries or stat information, they had better be 644 * checking FTS_NS on the returned nodes. 645 */ 646 cderrno = 0; 647 if (nlinks || type == BREAD) 648 if (FCHDIR(sp, dirfd(dirp))) { 649 if (nlinks && type == BREAD) 650 cur->fts_errno = errno; 651 cur->fts_flags |= FTS_DONTCHDIR; 652 descend = 0; 653 cderrno = errno; 654 } else 655 descend = 1; 656 else 657 descend = 0; 658 659 /* 660 * Figure out the max file name length that can be stored in the 661 * current path -- the inner loop allocates more path as necessary. 662 * We really wouldn't have to do the maxlen calculations here, we 663 * could do them in fts_read before returning the path, but it's a 664 * lot easier here since the length is part of the dirent structure. 665 * 666 * If not changing directories set a pointer so that can just append 667 * each new name into the path. 668 */ 669 maxlen = sp->fts_pathlen - cur->fts_pathlen - 1; 670 len = NAPPEND(cur); 671 if (ISSET(FTS_NOCHDIR)) { 672 cp = sp->fts_path + len; 673 *cp++ = '/'; 674 } 675 676 level = cur->fts_level + 1; 677 678 /* Read the directory, attaching each entry to the `link' pointer. */ 679 adjaddr = NULL; 680 for (head = tail = NULL, nitems = 0; (dp = readdir(dirp)) != NULL;) { 681 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 682 continue; 683 684 if ((p = fts_alloc(sp, dp->d_name, (int)dp->d_namlen)) == NULL) 685 goto mem1; 686 if (dp->d_namlen > maxlen) { 687 if (fts_palloc(sp, (size_t)dp->d_namlen)) { 688 /* 689 * No more memory for path or structures. Save 690 * errno, free up the current structure and the 691 * structures already allocated. 692 */ 693mem1: saved_errno = errno; 694 if (p) 695 free(p); 696 fts_lfree(head); 697 (void)closedir(dirp); 698 errno = saved_errno; 699 cur->fts_info = FTS_ERR; 700 SET(FTS_STOP); 701 return (NULL); 702 } 703 adjaddr = sp->fts_path; 704 maxlen = sp->fts_pathlen - sp->fts_cur->fts_pathlen - 1; 705 } 706 707 p->fts_pathlen = len + dp->d_namlen + 1; 708 p->fts_parent = sp->fts_cur; 709 p->fts_level = level; 710 711#ifdef FTS_WHITEOUT 712 if (dp->d_type == DT_WHT) 713 p->fts_flags |= FTS_ISW; 714#endif 715 716 if (cderrno) { 717 if (nlinks) { 718 p->fts_info = FTS_NS; 719 p->fts_errno = cderrno; 720 } else 721 p->fts_info = FTS_NSOK; 722 p->fts_accpath = cur->fts_accpath; 723 } else if (nlinks == 0 724#ifdef DT_DIR 725 || (nlinks > 0 && 726 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN) 727#endif 728 ) { 729 p->fts_accpath = 730 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 731 p->fts_info = FTS_NSOK; 732 } else { 733 /* Build a file name for fts_stat to stat. */ 734 if (ISSET(FTS_NOCHDIR)) { 735 p->fts_accpath = p->fts_path; 736 memmove(cp, p->fts_name, p->fts_namelen + 1); 737 } else 738 p->fts_accpath = p->fts_name; 739 /* Stat it. */ 740 p->fts_info = fts_stat(sp, p, 0); 741 742 /* Decrement link count if applicable. */ 743 if (nlinks > 0 && (p->fts_info == FTS_D || 744 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 745 --nlinks; 746 } 747 748 /* We walk in directory order so "ls -f" doesn't get upset. */ 749 p->fts_link = NULL; 750 if (head == NULL) 751 head = tail = p; 752 else { 753 tail->fts_link = p; 754 tail = p; 755 } 756 ++nitems; 757 } 758 (void)closedir(dirp); 759 760 /* 761 * If had to realloc the path, adjust the addresses for the rest 762 * of the tree. 763 */ 764 if (adjaddr) 765 fts_padjust(sp, adjaddr); 766 767 /* 768 * If not changing directories, reset the path back to original 769 * state. 770 */ 771 if (ISSET(FTS_NOCHDIR)) { 772 if (cp - 1 > sp->fts_path) 773 --cp; 774 *cp = '\0'; 775 } 776 777 /* 778 * If descended after called from fts_children or after called from 779 * fts_read and nothing found, get back. At the root level we use 780 * the saved fd; if one of fts_open()'s arguments is a relative path 781 * to an empty directory, we wind up here with no other way back. If 782 * can't get back, we're done. 783 */ 784 if (descend && (type == BCHILD || !nitems) && 785 (cur->fts_level == FTS_ROOTLEVEL ? 786 FCHDIR(sp, sp->fts_rfd) : CHDIR(sp, ".."))) { 787 cur->fts_info = FTS_ERR; 788 SET(FTS_STOP); 789 return (NULL); 790 } 791 792 /* If didn't find anything, return NULL. */ 793 if (!nitems) { 794 if (type == BREAD) 795 cur->fts_info = FTS_DP; 796 return (NULL); 797 } 798 799 /* Sort the entries. */ 800 if (sp->fts_compar && nitems > 1) 801 head = fts_sort(sp, head, nitems); 802 return (head); 803} 804 805static u_short 806fts_stat(sp, p, follow) 807 FTS *sp; 808 register FTSENT *p; 809 int follow; 810{ 811 register FTSENT *t; 812 register dev_t dev; 813 register ino_t ino; 814 struct stat12 *sbp, sb; 815 int saved_errno; 816 817 /* If user needs stat info, stat buffer already allocated. */ 818 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 819 820#ifdef FTS_WHITEOUT 821 /* check for whiteout */ 822 if (p->fts_flags & FTS_ISW) { 823 if (sbp != &sb) { 824 memset(sbp, '\0', sizeof (*sbp)); 825 sbp->st_mode = S_IFWHT; 826 } 827 return (FTS_W); 828 } 829#endif 830 831 /* 832 * If doing a logical walk, or application requested FTS_FOLLOW, do 833 * a stat(2). If that fails, check for a non-existent symlink. If 834 * fail, set the errno from the stat call. 835 */ 836 if (ISSET(FTS_LOGICAL) || follow) { 837 if (stat(p->fts_accpath, sbp)) { 838 saved_errno = errno; 839 if (!lstat(p->fts_accpath, sbp)) { 840 errno = 0; 841 return (FTS_SLNONE); 842 } 843 p->fts_errno = saved_errno; 844 goto err; 845 } 846 } else if (lstat(p->fts_accpath, sbp)) { 847 p->fts_errno = errno; 848err: memset(sbp, 0, sizeof(struct stat12)); 849 return (FTS_NS); 850 } 851 852 if (S_ISDIR(sbp->st_mode)) { 853 /* 854 * Set the device/inode. Used to find cycles and check for 855 * crossing mount points. Also remember the link count, used 856 * in fts_build to limit the number of stat calls. It is 857 * understood that these fields are only referenced if fts_info 858 * is set to FTS_D. 859 */ 860 dev = p->fts_dev = sbp->st_dev; 861 ino = p->fts_ino = sbp->st_ino; 862 p->fts_nlink = sbp->st_nlink; 863 864 if (ISDOT(p->fts_name)) 865 return (FTS_DOT); 866 867 /* 868 * Cycle detection is done by brute force when the directory 869 * is first encountered. If the tree gets deep enough or the 870 * number of symbolic links to directories is high enough, 871 * something faster might be worthwhile. 872 */ 873 for (t = p->fts_parent; 874 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 875 if (ino == t->fts_ino && dev == t->fts_dev) { 876 p->fts_cycle = t; 877 return (FTS_DC); 878 } 879 return (FTS_D); 880 } 881 if (S_ISLNK(sbp->st_mode)) 882 return (FTS_SL); 883 if (S_ISREG(sbp->st_mode)) 884 return (FTS_F); 885 return (FTS_DEFAULT); 886} 887 888static FTSENT * 889fts_sort(sp, head, nitems) 890 FTS *sp; 891 FTSENT *head; 892 register int nitems; 893{ 894 register FTSENT **ap, *p; 895 896 /* 897 * Construct an array of pointers to the structures and call qsort(3). 898 * Reassemble the array in the order returned by qsort. If unable to 899 * sort for memory reasons, return the directory entries in their 900 * current order. Allocate enough space for the current needs plus 901 * 40 so don't realloc one entry at a time. 902 */ 903 if (nitems > sp->fts_nitems) { 904 sp->fts_nitems = nitems + 40; 905 if ((sp->fts_array = realloc(sp->fts_array, 906 (size_t)(sp->fts_nitems * sizeof(FTSENT *)))) == NULL) { 907 sp->fts_nitems = 0; 908 return (head); 909 } 910 } 911 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 912 *ap++ = p; 913 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), sp->fts_compar); 914 for (head = *(ap = sp->fts_array); --nitems; ++ap) 915 ap[0]->fts_link = ap[1]; 916 ap[0]->fts_link = NULL; 917 return (head); 918} 919 920static FTSENT * 921fts_alloc(sp, name, namelen) 922 FTS *sp; 923 char *name; 924 register int namelen; 925{ 926 register FTSENT *p; 927 size_t len; 928 929 /* 930 * The file name is a variable length array and no stat structure is 931 * necessary if the user has set the nostat bit. Allocate the FTSENT 932 * structure, the file name and the stat structure in one chunk, but 933 * be careful that the stat structure is reasonably aligned. Since the 934 * fts_name field is declared to be of size 1, the fts_name pointer is 935 * namelen + 2 before the first possible address of the stat structure. 936 */ 937 len = sizeof(FTSENT) + namelen; 938 if (!ISSET(FTS_NOSTAT)) 939 len += sizeof(struct stat12) + ALIGNBYTES; 940 if ((p = malloc(len)) == NULL) 941 return (NULL); 942 943 /* Copy the name plus the trailing NULL. */ 944 memmove(p->fts_name, name, namelen + 1); 945 946 if (!ISSET(FTS_NOSTAT)) 947 p->fts_statp = (struct stat12 *)ALIGN(p->fts_name + namelen + 2); 948 p->fts_namelen = namelen; 949 p->fts_path = sp->fts_path; 950 p->fts_errno = 0; 951 p->fts_flags = 0; 952 p->fts_instr = FTS_NOINSTR; 953 p->fts_number = 0; 954 p->fts_pointer = NULL; 955 return (p); 956} 957 958static void 959fts_lfree(head) 960 register FTSENT *head; 961{ 962 register FTSENT *p; 963 964 /* Free a linked list of structures. */ 965 while ((p = head) != NULL) { 966 head = head->fts_link; 967 free(p); 968 } 969} 970 971/* 972 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 973 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 974 * though the kernel won't resolve them. Add the size (not just what's needed) 975 * plus 256 bytes so don't realloc the path 2 bytes at a time. 976 */ 977static int 978fts_palloc(sp, more) 979 FTS *sp; 980 size_t more; 981{ 982 sp->fts_pathlen += more + 256; 983 sp->fts_path = realloc(sp->fts_path, (size_t)sp->fts_pathlen); 984 return (sp->fts_path == NULL); 985} 986 987/* 988 * When the path is realloc'd, have to fix all of the pointers in structures 989 * already returned. 990 */ 991static void 992fts_padjust(sp, addr) 993 FTS *sp; 994 void *addr; 995{ 996 FTSENT *p; 997 998#define ADJUST(p) { \ 999 (p)->fts_accpath = \ 1000 (char *)addr + ((p)->fts_accpath - (p)->fts_path); \ 1001 (p)->fts_path = addr; \ 1002} 1003 /* Adjust the current set of children. */ 1004 for (p = sp->fts_child; p; p = p->fts_link) 1005 ADJUST(p); 1006 1007 /* Adjust the rest of the tree. */ 1008 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 1009 ADJUST(p); 1010 p = p->fts_link ? p->fts_link : p->fts_parent; 1011 } 1012} 1013 1014static size_t 1015fts_maxarglen(argv) 1016 char * const *argv; 1017{ 1018 size_t len, max; 1019 1020 for (max = 0; *argv; ++argv) 1021 if ((len = strlen(*argv)) > max) 1022 max = len; 1023 return (max); 1024} 1025