1 /*- 2 * Copyright (c) 1990 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #if defined(LIBC_SCCS) && !defined(lint) 9 static char sccsid[] = "@(#)fts.c 5.41 (Berkeley) 03/07/93"; 10 #endif /* LIBC_SCCS and not lint */ 11 12 #include <sys/param.h> 13 #include <sys/stat.h> 14 #include <fcntl.h> 15 #include <dirent.h> 16 #include <errno.h> 17 #include <fts.h> 18 #include <stdlib.h> 19 #include <string.h> 20 #include <unistd.h> 21 22 static FTSENT *fts_alloc __P((FTS *, char *, int)); 23 static FTSENT *fts_build __P((FTS *, int)); 24 static void fts_lfree __P((FTSENT *)); 25 static void fts_load __P((FTS *, FTSENT *)); 26 static size_t fts_maxarglen __P((char * const *)); 27 static void fts_padjust __P((FTS *, void *)); 28 static int fts_palloc __P((FTS *, size_t)); 29 static FTSENT *fts_sort __P((FTS *, FTSENT *, int)); 30 static u_short fts_stat __P((FTS *, FTSENT *, int)); 31 32 #define ISDOT(a) (a[0] == '.' && (!a[1] || a[1] == '.' && !a[2])) 33 34 #define ISSET(opt) (sp->fts_options & opt) 35 #define SET(opt) (sp->fts_options |= opt) 36 37 #define CHDIR(sp, path) (!ISSET(FTS_NOCHDIR) && chdir(path)) 38 #define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) && fchdir(fd)) 39 40 /* fts_build flags */ 41 #define BCHILD 1 /* fts_children */ 42 #define BNAMES 2 /* fts_children, names only */ 43 #define BREAD 3 /* fts_read */ 44 45 FTS * 46 fts_open(argv, options, compar) 47 char * const *argv; 48 register int options; 49 int (*compar)(); 50 { 51 register FTS *sp; 52 register FTSENT *p, *root; 53 register int nitems; 54 FTSENT *parent, *tmp; 55 int len; 56 57 /* Options check. */ 58 if (options & ~FTS_OPTIONMASK) { 59 errno = EINVAL; 60 return (NULL); 61 } 62 63 /* Allocate/initialize the stream */ 64 if ((sp = malloc((u_int)sizeof(FTS))) == NULL) 65 return (NULL); 66 bzero(sp, sizeof(FTS)); 67 sp->fts_compar = compar; 68 sp->fts_options = options; 69 70 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 71 if (ISSET(FTS_LOGICAL)) 72 SET(FTS_NOCHDIR); 73 74 /* 75 * Start out with 1K of path space, and enough, in any case, 76 * to hold the user's paths. 77 */ 78 if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN))) 79 goto mem1; 80 81 /* Allocate/initialize root's parent. */ 82 if ((parent = fts_alloc(sp, "", 0)) == NULL) 83 goto mem2; 84 parent->fts_level = FTS_ROOTPARENTLEVEL; 85 86 /* Allocate/initialize root(s). */ 87 for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) { 88 /* Don't allow zero-length paths. */ 89 if ((len = strlen(*argv)) == 0) { 90 errno = ENOENT; 91 goto mem3; 92 } 93 94 p = fts_alloc(sp, *argv, len); 95 p->fts_level = FTS_ROOTLEVEL; 96 p->fts_parent = parent; 97 p->fts_accpath = p->fts_name; 98 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 99 100 /* Command-line "." and ".." are real directories. */ 101 if (p->fts_info == FTS_DOT) 102 p->fts_info = FTS_D; 103 104 /* 105 * If comparison routine supplied, traverse in sorted 106 * order; otherwise traverse in the order specified. 107 */ 108 if (compar) { 109 p->fts_link = root; 110 root = p; 111 } else { 112 p->fts_link = NULL; 113 if (root == NULL) 114 tmp = root = p; 115 else { 116 tmp->fts_link = p; 117 tmp = p; 118 } 119 } 120 } 121 if (compar && nitems > 1) 122 root = fts_sort(sp, root, nitems); 123 124 /* 125 * Allocate a dummy pointer and make fts_read think that we've just 126 * finished the node before the root(s); set p->fts_info to FTS_INIT 127 * so that everything about the "current" node is ignored. 128 */ 129 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 130 goto mem3; 131 sp->fts_cur->fts_link = root; 132 sp->fts_cur->fts_info = FTS_INIT; 133 134 /* 135 * If using chdir(2), grab a file descriptor pointing to dot to insure 136 * that we can get back here; this could be avoided for some paths, 137 * but almost certainly not worth the effort. Slashes, symbolic links, 138 * and ".." are all fairly nasty problems. Note, if we can't get the 139 * descriptor we run anyway, just more slowly. 140 */ 141 if (!ISSET(FTS_NOCHDIR) && (sp->fts_rfd = open(".", O_RDONLY, 0)) < 0) 142 SET(FTS_NOCHDIR); 143 144 return (sp); 145 146 mem3: fts_lfree(root); 147 free(parent); 148 mem2: free(sp->fts_path); 149 mem1: free(sp); 150 return (NULL); 151 } 152 153 static void 154 fts_load(sp, p) 155 FTS *sp; 156 register FTSENT *p; 157 { 158 register int len; 159 register char *cp; 160 161 /* 162 * Load the stream structure for the next traversal. Since we don't 163 * actually enter the directory until after the preorder visit, set 164 * the fts_accpath field specially so the chdir gets done to the right 165 * place and the user can access the first node. From fts_open it's 166 * known that the path will fit. 167 */ 168 len = p->fts_pathlen = p->fts_namelen; 169 bcopy(p->fts_name, sp->fts_path, len + 1); 170 if ((cp = rindex(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 171 len = strlen(++cp); 172 bcopy(cp, p->fts_name, len + 1); 173 p->fts_namelen = len; 174 } 175 p->fts_accpath = p->fts_path = sp->fts_path; 176 sp->fts_dev = p->fts_dev; 177 } 178 179 int 180 fts_close(sp) 181 FTS *sp; 182 { 183 register FTSENT *freep, *p; 184 int saved_errno; 185 186 /* 187 * This still works if we haven't read anything -- the dummy structure 188 * points to the root list, so we step through to the end of the root 189 * list which has a valid parent pointer. 190 */ 191 if (sp->fts_cur) { 192 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 193 freep = p; 194 p = p->fts_link ? p->fts_link : p->fts_parent; 195 free(freep); 196 } 197 free(p); 198 } 199 200 /* Free up child linked list, sort array, path buffer. */ 201 if (sp->fts_child) 202 fts_lfree(sp->fts_child); 203 if (sp->fts_array) 204 free(sp->fts_array); 205 free(sp->fts_path); 206 207 /* Return to original directory, save errno if necessary. */ 208 if (!ISSET(FTS_NOCHDIR)) { 209 saved_errno = fchdir(sp->fts_rfd) ? errno : 0; 210 (void)close(sp->fts_rfd); 211 } 212 213 /* Free up the stream pointer. */ 214 free(sp); 215 216 /* Set errno and return. */ 217 if (!ISSET(FTS_NOCHDIR) && saved_errno) { 218 errno = saved_errno; 219 return (-1); 220 } 221 return (0); 222 } 223 224 /* 225 * Special case a root of "/" so that slashes aren't appended which would 226 * cause paths to be written as "//foo". 227 */ 228 #define NAPPEND(p) \ 229 (p->fts_level == FTS_ROOTLEVEL && p->fts_pathlen == 1 && \ 230 p->fts_path[0] == '/' ? 0 : p->fts_pathlen) 231 232 FTSENT * 233 fts_read(sp) 234 register FTS *sp; 235 { 236 register FTSENT *p, *tmp; 237 register int instr; 238 register char *t; 239 int saved_errno; 240 241 /* If finished or unrecoverable error, return NULL. */ 242 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 243 return (NULL); 244 245 /* Set current node pointer. */ 246 p = sp->fts_cur; 247 248 /* Save and zero out user instructions. */ 249 instr = p->fts_instr; 250 p->fts_instr = FTS_NOINSTR; 251 252 /* Any type of file may be re-visited; re-stat and re-turn. */ 253 if (instr == FTS_AGAIN) { 254 p->fts_info = fts_stat(sp, p, 0); 255 return (p); 256 } 257 258 /* 259 * Following a symlink -- SLNONE test allows application to see 260 * SLNONE and recover. If indirecting through a symlink, have 261 * keep a pointer to current location. If unable to get that 262 * pointer, follow fails. 263 */ 264 if (instr == FTS_FOLLOW && 265 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 266 p->fts_info = fts_stat(sp, p, 1); 267 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) 268 if ((p->fts_symfd = open(".", O_RDONLY, 0)) < 0) { 269 p->fts_errno = errno; 270 p->fts_info = FTS_ERR; 271 } else 272 p->fts_flags |= FTS_SYMFOLLOW; 273 return (p); 274 } 275 276 /* Directory in pre-order. */ 277 if (p->fts_info == FTS_D) { 278 /* If skipped or crossed mount point, do post-order visit. */ 279 if (instr == FTS_SKIP || 280 ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev) { 281 if (p->fts_flags & FTS_SYMFOLLOW) 282 (void)close(p->fts_symfd); 283 if (sp->fts_child) { 284 fts_lfree(sp->fts_child); 285 sp->fts_child = NULL; 286 } 287 p->fts_info = FTS_DP; 288 return (p); 289 } 290 291 /* Rebuild if only read the names and now traversing. */ 292 if (sp->fts_child && sp->fts_options & FTS_NAMEONLY) { 293 sp->fts_options &= ~FTS_NAMEONLY; 294 fts_lfree(sp->fts_child); 295 sp->fts_child = NULL; 296 } 297 298 /* 299 * Cd to the subdirectory. 300 * 301 * If have already read and now fail to chdir, whack the list 302 * to make the names come out right, and set the parent errno 303 * so the application will eventually get an error condition. 304 * Set the FTS_DONTCHDIR flag so that when we logically change 305 * directories back to the parent we don't do a chdir. 306 * 307 * If haven't read do so. If the read fails, fts_build sets 308 * FTS_STOP or the fts_info field of the node. 309 */ 310 if (sp->fts_child) { 311 if (CHDIR(sp, p->fts_accpath)) { 312 p->fts_errno = errno; 313 p->fts_flags |= FTS_DONTCHDIR; 314 for (p = sp->fts_child; p; p = p->fts_link) 315 p->fts_accpath = 316 p->fts_parent->fts_accpath; 317 } 318 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 319 if (ISSET(FTS_STOP)) 320 return (NULL); 321 return (p); 322 } 323 p = sp->fts_child; 324 sp->fts_child = NULL; 325 goto name; 326 } 327 328 /* Move to the next node on this level. */ 329 next: tmp = p; 330 if (p = p->fts_link) { 331 free(tmp); 332 333 /* 334 * If reached the top, return to the original directory, and 335 * load the paths for the next root. 336 */ 337 if (p->fts_level == FTS_ROOTLEVEL) { 338 if (!ISSET(FTS_NOCHDIR) && FCHDIR(sp, sp->fts_rfd)) { 339 SET(FTS_STOP); 340 return (NULL); 341 } 342 fts_load(sp, p); 343 return (sp->fts_cur = p); 344 } 345 346 /* 347 * User may have called fts_set on the node. If skipped, 348 * ignore. If followed, get a file descriptor so we can 349 * get back if necessary. 350 */ 351 if (p->fts_instr == FTS_SKIP) 352 goto next; 353 if (p->fts_instr == FTS_FOLLOW) { 354 p->fts_info = fts_stat(sp, p, 1); 355 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) 356 if ((p->fts_symfd = 357 open(".", O_RDONLY, 0)) < 0) { 358 p->fts_errno = errno; 359 p->fts_info = FTS_ERR; 360 } else 361 p->fts_flags |= FTS_SYMFOLLOW; 362 p->fts_instr = FTS_NOINSTR; 363 } 364 365 name: t = sp->fts_path + NAPPEND(p->fts_parent); 366 *t++ = '/'; 367 bcopy(p->fts_name, t, p->fts_namelen + 1); 368 return (sp->fts_cur = p); 369 } 370 371 /* Move up to the parent node. */ 372 p = tmp->fts_parent; 373 free(tmp); 374 375 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 376 /* 377 * Done; free everything up and set errno to 0 so the user 378 * can distinguish between error and EOF. 379 */ 380 free(p); 381 errno = 0; 382 return (sp->fts_cur = NULL); 383 } 384 385 /* Nul terminate the pathname. */ 386 sp->fts_path[p->fts_pathlen] = '\0'; 387 388 /* 389 * Return to the parent directory. If at a root node or came through 390 * a symlink, go back through the file descriptor. Otherwise, cd up 391 * one directory. 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 } else if (p->fts_flags & FTS_SYMFOLLOW) { 399 if (FCHDIR(sp, p->fts_symfd)) { 400 saved_errno = errno; 401 (void)close(p->fts_symfd); 402 errno = saved_errno; 403 SET(FTS_STOP); 404 return (NULL); 405 } 406 (void)close(p->fts_symfd); 407 } else if (!(p->fts_flags & FTS_DONTCHDIR)) { 408 if (CHDIR(sp, "..")) { 409 SET(FTS_STOP); 410 return (NULL); 411 } 412 } 413 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 414 return (sp->fts_cur = p); 415 } 416 417 /* 418 * Fts_set takes the stream as an argument although it's not used in this 419 * implementation; it would be necessary if anyone wanted to add global 420 * semantics to fts using fts_set. An error return is allowed for similar 421 * reasons. 422 */ 423 /* ARGSUSED */ 424 int 425 fts_set(sp, p, instr) 426 FTS *sp; 427 FTSENT *p; 428 int instr; 429 { 430 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW && 431 instr != FTS_NOINSTR && instr != FTS_SKIP) { 432 errno = EINVAL; 433 return (1); 434 } 435 p->fts_instr = instr; 436 return (0); 437 } 438 439 FTSENT * 440 fts_children(sp, instr) 441 register FTS *sp; 442 int instr; 443 { 444 register FTSENT *p; 445 int fd; 446 447 if (instr && instr != FTS_NAMEONLY) { 448 errno = EINVAL; 449 return (NULL); 450 } 451 452 /* Set current node pointer. */ 453 p = sp->fts_cur; 454 455 /* 456 * Errno set to 0 so user can distinguish empty directory from 457 * an error. 458 */ 459 errno = 0; 460 461 /* Fatal errors stop here. */ 462 if (ISSET(FTS_STOP)) 463 return (NULL); 464 465 /* Return logical hierarchy of user's arguments. */ 466 if (p->fts_info == FTS_INIT) 467 return (p->fts_link); 468 469 /* 470 * If not a directory being visited in pre-order, stop here. Could 471 * allow FTS_DNR, assuming the user has fixed the problem, but the 472 * same effect is available with FTS_AGAIN. 473 */ 474 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 475 return (NULL); 476 477 /* Free up any previous child list. */ 478 if (sp->fts_child) 479 fts_lfree(sp->fts_child); 480 481 if (instr == FTS_NAMEONLY) { 482 sp->fts_options |= FTS_NAMEONLY; 483 instr = BNAMES; 484 } else 485 instr = BCHILD; 486 487 /* 488 * If using chdir on a relative path and called BEFORE fts_read does 489 * its chdir to the root of a traversal, we can lose -- we need to 490 * chdir into the subdirectory, and we don't know where the current 491 * directory is, so we can't get back so that the upcoming chdir by 492 * fts_read will work. 493 */ 494 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 495 ISSET(FTS_NOCHDIR)) 496 return (sp->fts_child = fts_build(sp, instr)); 497 498 if ((fd = open(".", O_RDONLY, 0)) < 0) 499 return (NULL); 500 sp->fts_child = fts_build(sp, instr); 501 if (fchdir(fd)) 502 return (NULL); 503 (void)close(fd); 504 return (sp->fts_child); 505 } 506 507 /* 508 * This is the tricky part -- do not casually change *anything* in here. The 509 * idea is to build the linked list of entries that are used by fts_children 510 * and fts_read. There are lots of special cases. 511 * 512 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 513 * set and it's a physical walk (so that symbolic links can't be directories), 514 * we assume that the number of subdirectories in a node is equal to the number 515 * of links to the parent. This allows stat calls to be skipped in any leaf 516 * directories and for any nodes after the directories in the parent node have 517 * been found. This empirically cuts the stat calls by about 2/3. 518 */ 519 static FTSENT * 520 fts_build(sp, type) 521 register FTS *sp; 522 int type; 523 { 524 register struct dirent *dp; 525 register FTSENT *p, *head; 526 register int nitems; 527 FTSENT *cur, *tail; 528 DIR *dirp; 529 void *adjaddr; 530 int cderrno, descend, len, level, maxlen, nlinks, saved_errno; 531 char *cp; 532 533 /* Set current node pointer. */ 534 cur = sp->fts_cur; 535 536 /* 537 * Open the directory for reading. If this fails, we're done. 538 * If being called from fts_read, set the fts_info field. 539 */ 540 if ((dirp = opendir(cur->fts_accpath)) == NULL) { 541 if (type == BREAD) { 542 cur->fts_info = FTS_DNR; 543 cur->fts_errno = errno; 544 } 545 return (NULL); 546 } 547 548 /* 549 * Nlinks is the number of possible entries of type directory in the 550 * directory if we're cheating on stat calls, 0 if we're not doing 551 * any stat calls at all, -1 if we're doing stats on everything. 552 */ 553 if (type == BNAMES) 554 nlinks = 0; 555 else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) 556 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 557 else 558 nlinks = -1; 559 560 #ifdef notdef 561 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 562 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 563 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 564 #endif 565 /* 566 * If we're going to need to stat anything or we want to descend 567 * and stay in the directory, chdir. If this fails we keep going, 568 * but set a flag so we don't chdir after the post-order visit. 569 * We won't be able to stat anything, but we can still return the 570 * names themselves. Note, that since fts_read won't be able to 571 * chdir into the directory, it will have to return different path 572 * names than before, i.e. "a/b" instead of "b". Since the node 573 * has already been visited in pre-order, have to wait until the 574 * post-order visit to return the error. There is a special case 575 * here, if there was nothing to stat then it's not an error to 576 * not be able to stat. This is all fairly nasty. If a program 577 * needed sorted entries or stat information, they had better be 578 * checking FTS_NS on the returned nodes. 579 */ 580 cderrno = 0; 581 if (nlinks || type == BREAD) 582 if (FCHDIR(sp, dirfd(dirp))) { 583 if (nlinks && type == BREAD) 584 cur->fts_errno = errno; 585 cur->fts_flags |= FTS_DONTCHDIR; 586 descend = 0; 587 cderrno = errno; 588 } else 589 descend = 1; 590 else 591 descend = 0; 592 593 /* 594 * Figure out the max file name length that can be stored in the 595 * current path -- the inner loop allocates more path as necessary. 596 * We really wouldn't have to do the maxlen calculations here, we 597 * could do them in fts_read before returning the path, but it's a 598 * lot easier here since the length is part of the dirent structure. 599 * 600 * If not changing directories set a pointer so that can just append 601 * each new name into the path. 602 */ 603 maxlen = sp->fts_pathlen - cur->fts_pathlen - 1; 604 len = NAPPEND(cur); 605 if (ISSET(FTS_NOCHDIR)) { 606 cp = sp->fts_path + len; 607 *cp++ = '/'; 608 } 609 610 level = cur->fts_level + 1; 611 612 /* Read the directory, attaching each entry to the `link' pointer. */ 613 adjaddr = NULL; 614 for (head = tail = NULL, nitems = 0; dp = readdir(dirp);) { 615 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 616 continue; 617 618 if ((p = fts_alloc(sp, dp->d_name, (int)dp->d_namlen)) == NULL) 619 goto mem1; 620 if (dp->d_namlen > maxlen) { 621 if (fts_palloc(sp, (size_t)dp->d_namlen)) { 622 /* 623 * No more memory for path or structures. Save 624 * errno, free up the current structure and the 625 * structures already allocated. 626 */ 627 mem1: saved_errno = errno; 628 if (p) 629 free(p); 630 fts_lfree(head); 631 (void)closedir(dirp); 632 errno = saved_errno; 633 cur->fts_info = FTS_ERR; 634 SET(FTS_STOP); 635 return (NULL); 636 } 637 adjaddr = sp->fts_path; 638 maxlen = sp->fts_pathlen - sp->fts_cur->fts_pathlen - 1; 639 } 640 641 p->fts_pathlen = len + dp->d_namlen + 1; 642 p->fts_parent = sp->fts_cur; 643 p->fts_level = level; 644 645 if (cderrno) { 646 if (nlinks) { 647 p->fts_info = FTS_NS; 648 p->fts_errno = cderrno; 649 } else 650 p->fts_info = FTS_NSOK; 651 p->fts_accpath = cur->fts_accpath; 652 } else if (nlinks) { 653 /* Build a file name for fts_stat to stat. */ 654 if (ISSET(FTS_NOCHDIR)) { 655 p->fts_accpath = p->fts_path; 656 bcopy(p->fts_name, cp, p->fts_namelen + 1); 657 } else 658 p->fts_accpath = p->fts_name; 659 p->fts_info = fts_stat(sp, p, 0); 660 if (nlinks > 0 && (p->fts_info == FTS_D || 661 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 662 --nlinks; 663 } else { 664 p->fts_accpath = 665 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 666 p->fts_info = FTS_NSOK; 667 } 668 669 /* We walk in directory order so "ls -f" doesn't get upset. */ 670 p->fts_link = NULL; 671 if (head == NULL) 672 head = tail = p; 673 else { 674 tail->fts_link = p; 675 tail = p; 676 } 677 ++nitems; 678 } 679 (void)closedir(dirp); 680 681 /* 682 * If had to realloc the path, adjust the addresses for the rest 683 * of the tree. 684 */ 685 if (adjaddr) 686 fts_padjust(sp, adjaddr); 687 688 /* 689 * If not changing directories, reset the path back to original 690 * state. 691 */ 692 if (ISSET(FTS_NOCHDIR)) { 693 if (cp - 1 > sp->fts_path) 694 --cp; 695 *cp = '\0'; 696 } 697 698 /* 699 * If descended after called from fts_children or called from 700 * fts_read and didn't find anything, get back. If can't get 701 * back, done. 702 */ 703 if (descend && (!nitems || type == BCHILD) && CHDIR(sp, "..")) { 704 cur->fts_info = FTS_ERR; 705 SET(FTS_STOP); 706 return (NULL); 707 } 708 709 /* If didn't find anything, return NULL. */ 710 if (!nitems) { 711 if (type == BREAD) 712 cur->fts_info = FTS_DP; 713 return (NULL); 714 } 715 716 /* Sort the entries. */ 717 if (sp->fts_compar && nitems > 1) 718 head = fts_sort(sp, head, nitems); 719 return (head); 720 } 721 722 static u_short 723 fts_stat(sp, p, follow) 724 FTS *sp; 725 register FTSENT *p; 726 int follow; 727 { 728 register FTSENT *t; 729 register dev_t dev; 730 register ino_t ino; 731 struct stat *sbp, sb; 732 int saved_errno; 733 734 /* If user needs stat info, stat buffer already allocated. */ 735 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 736 737 /* 738 * If doing a logical walk, or application requested FTS_FOLLOW, do 739 * a stat(2). If that fails, check for a non-existent symlink. If 740 * fail, set the errno from the stat call. 741 */ 742 if (ISSET(FTS_LOGICAL) || follow) { 743 if (stat(p->fts_accpath, sbp)) { 744 saved_errno = errno; 745 if (!lstat(p->fts_accpath, sbp)) { 746 errno = 0; 747 return (FTS_SLNONE); 748 } 749 p->fts_errno = saved_errno; 750 goto err; 751 } 752 } else if (lstat(p->fts_accpath, sbp)) { 753 p->fts_errno = errno; 754 err: bzero(sbp, sizeof(struct stat)); 755 return (FTS_NS); 756 } 757 758 if (S_ISDIR(sbp->st_mode)) { 759 /* 760 * Set the device/inode. Used to find cycles and check for 761 * crossing mount points. Also remember the link count, used 762 * in fts_build to limit the number of stat calls. It is 763 * understood that these fields are only referenced if fts_info 764 * is set to FTS_D. 765 */ 766 dev = p->fts_dev = sbp->st_dev; 767 ino = p->fts_ino = sbp->st_ino; 768 p->fts_nlink = sbp->st_nlink; 769 770 if (ISDOT(p->fts_name)) 771 return (FTS_DOT); 772 773 /* 774 * Cycle detection is done by brute force when the directory 775 * is first encountered. If the tree gets deep enough or the 776 * number of symbolic links to directories is high enough, 777 * something faster might be worthwhile. 778 */ 779 for (t = p->fts_parent; 780 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 781 if (ino == t->fts_ino && dev == t->fts_dev) { 782 p->fts_cycle = t; 783 return (FTS_DC); 784 } 785 return (FTS_D); 786 } 787 if (S_ISLNK(sbp->st_mode)) 788 return (FTS_SL); 789 if (S_ISREG(sbp->st_mode)) 790 return (FTS_F); 791 return (FTS_DEFAULT); 792 } 793 794 static FTSENT * 795 fts_sort(sp, head, nitems) 796 FTS *sp; 797 FTSENT *head; 798 register int nitems; 799 { 800 register FTSENT **ap, *p; 801 802 /* 803 * Construct an array of pointers to the structures and call qsort(3). 804 * Reassemble the array in the order returned by qsort. If unable to 805 * sort for memory reasons, return the directory entries in their 806 * current order. Allocate enough space for the current needs plus 807 * 40 so don't realloc one entry at a time. 808 */ 809 if (nitems > sp->fts_nitems) { 810 sp->fts_nitems = nitems + 40; 811 if ((sp->fts_array = realloc(sp->fts_array, 812 (size_t)(sp->fts_nitems * sizeof(FTSENT *)))) == NULL) { 813 sp->fts_nitems = 0; 814 return (head); 815 } 816 } 817 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 818 *ap++ = p; 819 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), sp->fts_compar); 820 for (head = *(ap = sp->fts_array); --nitems; ++ap) 821 ap[0]->fts_link = ap[1]; 822 ap[0]->fts_link = NULL; 823 return (head); 824 } 825 826 static FTSENT * 827 fts_alloc(sp, name, namelen) 828 FTS *sp; 829 char *name; 830 register int namelen; 831 { 832 register FTSENT *p; 833 size_t len; 834 835 /* 836 * The file name is a variable length array and no stat structure is 837 * necessary if the user has set the nostat bit. Allocate the FTSENT 838 * structure, the file name and the stat structure in one chunk, but 839 * be careful that the stat structure is reasonably aligned. Since the 840 * fts_name field is declared to be of size 1, the fts_name pointer is 841 * namelen + 2 before the first possible address of the stat structure. 842 */ 843 len = sizeof(FTSENT) + namelen; 844 if (!ISSET(FTS_NOSTAT)) 845 len += sizeof(struct stat) + ALIGNBYTES; 846 if ((p = malloc(len)) == NULL) 847 return (NULL); 848 849 /* Copy the name plus the trailing NULL. */ 850 bcopy(name, p->fts_name, namelen + 1); 851 852 if (!ISSET(FTS_NOSTAT)) 853 p->fts_statp = (struct stat *)ALIGN(p->fts_name + namelen + 2); 854 p->fts_namelen = namelen; 855 p->fts_path = sp->fts_path; 856 p->fts_errno = 0; 857 p->fts_flags = 0; 858 p->fts_instr = FTS_NOINSTR; 859 p->fts_number = 0; 860 p->fts_pointer = NULL; 861 return (p); 862 } 863 864 static void 865 fts_lfree(head) 866 register FTSENT *head; 867 { 868 register FTSENT *p; 869 870 /* Free a linked list of structures. */ 871 while (p = head) { 872 head = head->fts_link; 873 free(p); 874 } 875 } 876 877 /* 878 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 879 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 880 * though the kernel won't resolve them. Add the size (not just what's needed) 881 * plus 256 bytes so don't realloc the path 2 bytes at a time. 882 */ 883 static int 884 fts_palloc(sp, more) 885 FTS *sp; 886 size_t more; 887 { 888 sp->fts_pathlen += more + 256; 889 sp->fts_path = realloc(sp->fts_path, (size_t)sp->fts_pathlen); 890 return (sp->fts_path == NULL); 891 } 892 893 /* 894 * When the path is realloc'd, have to fix all of the pointers in structures 895 * already returned. 896 */ 897 static void 898 fts_padjust(sp, addr) 899 FTS *sp; 900 void *addr; 901 { 902 FTSENT *p; 903 904 #define ADJUST(p) { \ 905 (p)->fts_accpath = addr + ((p)->fts_accpath - (p)->fts_path); \ 906 (p)->fts_path = addr; \ 907 } 908 /* Adjust the current set of children. */ 909 for (p = sp->fts_child; p; p = p->fts_link) 910 ADJUST(p); 911 912 /* Adjust the rest of the tree. */ 913 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 914 ADJUST(p); 915 p = p->fts_link ? p->fts_link : p->fts_parent; 916 } 917 } 918 919 static size_t 920 fts_maxarglen(argv) 921 char * const *argv; 922 { 923 size_t len, max; 924 925 for (max = 0; *argv; ++argv) 926 if ((len = strlen(*argv)) > max) 927 max = len; 928 return (max); 929 } 930