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 5.32 (Berkeley) 03/01/92"; 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 void fts_padjust __P((FTS *, void *)); 27 static int fts_palloc __P((FTS *, int)); 28 static FTSENT *fts_sort __P((FTS *, FTSENT *, int)); 29 static u_short fts_stat __P((FTS *, FTSENT *, int)); 30 31 #define ISDOT(a) (a[0] == '.' && (!a[1] || a[1] == '.' && !a[2])) 32 33 #define ISSET(opt) (sp->fts_options & opt) 34 #define SET(opt) (sp->fts_options |= opt) 35 36 #define CHDIR(sp, path) (!ISSET(FTS_NOCHDIR) && chdir(path)) 37 #define FCHDIR(sp, fd) (!ISSET(FTS_NOCHDIR) && fchdir(fd)) 38 39 /* fts_build flags */ 40 #define BCHILD 1 /* fts_children */ 41 #define BNAMES 2 /* fts_children, names only */ 42 #define BREAD 3 /* fts_read */ 43 44 FTS * 45 fts_open(argv, options, compar) 46 char * const *argv; 47 register int options; 48 int (*compar)(); 49 { 50 register FTS *sp; 51 register FTSENT *p, *root; 52 register int nitems, maxlen; 53 FTSENT *parent, *tmp; 54 int len; 55 56 /* Options check. */ 57 if (options & ~FTS_OPTIONMASK) { 58 errno = EINVAL; 59 return (NULL); 60 } 61 62 /* Allocate/initialize the stream */ 63 if ((sp = malloc((u_int)sizeof(FTS))) == NULL) 64 return (NULL); 65 bzero(sp, sizeof(FTS)); 66 sp->fts_compar = compar; 67 sp->fts_options = options; 68 69 /* Logical walks turn on NOCHDIR; symbolic links are too hard. */ 70 if (ISSET(FTS_LOGICAL)) 71 SET(FTS_NOCHDIR); 72 73 /* Allocate/initialize root's parent. */ 74 if ((parent = fts_alloc(sp, "", 0)) == NULL) 75 goto mem1; 76 parent->fts_level = FTS_ROOTPARENTLEVEL; 77 78 /* Allocate/initialize root(s). */ 79 for (root = NULL, maxlen = nitems = 0; *argv; ++argv, ++nitems) { 80 /* Don't allow zero-length paths. */ 81 if ((len = strlen(*argv)) == 0) { 82 errno = ENOENT; 83 goto mem2; 84 } 85 if (maxlen < len) 86 maxlen = len; 87 88 p = fts_alloc(sp, *argv, len); 89 p->fts_level = FTS_ROOTLEVEL; 90 p->fts_parent = parent; 91 p->fts_accpath = p->fts_name; 92 p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW)); 93 94 /* Command-line "." and ".." are real directories. */ 95 if (p->fts_info == FTS_DOT) 96 p->fts_info = FTS_D; 97 98 /* 99 * If comparison routine supplied, traverse in sorted 100 * order; otherwise traverse in the order specified. 101 */ 102 if (compar) { 103 p->fts_link = root; 104 root = p; 105 } else { 106 p->fts_link = NULL; 107 if (root == NULL) 108 tmp = root = p; 109 else { 110 tmp->fts_link = p; 111 tmp = p; 112 } 113 } 114 } 115 if (compar && nitems > 1) 116 root = fts_sort(sp, root, nitems); 117 118 /* 119 * Allocate a dummy pointer and make fts_read think that we've just 120 * finished the node before the root(s); set p->fts_info to FTS_INIT 121 * so that everything about the "current" node is ignored. 122 */ 123 if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL) 124 goto mem2; 125 sp->fts_cur->fts_link = root; 126 sp->fts_cur->fts_info = FTS_INIT; 127 128 /* 129 * Start out with more than 1K of path space, and enough, in any 130 * case, to hold the user's paths. 131 */ 132 if (fts_palloc(sp, MAX(maxlen, MAXPATHLEN))) 133 goto mem3; 134 135 /* 136 * If using chdir(2), grab a file descriptor pointing to dot to insure 137 * that we can get back here; this could be avoided for some paths, 138 * but almost certainly not worth the effort. Slashes, symbolic links, 139 * and ".." are all fairly nasty problems. Note, if we can't get the 140 * descriptor we run anyway, just more slowly. 141 */ 142 if (!ISSET(FTS_NOCHDIR) && (sp->fts_rfd = open(".", O_RDONLY, 0)) < 0) 143 SET(FTS_NOCHDIR); 144 145 return (sp); 146 147 mem3: free(sp->fts_cur); 148 mem2: fts_lfree(root); 149 free(parent); 150 mem1: free(sp); 151 return (NULL); 152 } 153 154 static void 155 fts_load(sp, p) 156 FTS *sp; 157 register FTSENT *p; 158 { 159 register int len; 160 register char *cp; 161 162 /* 163 * Load the stream structure for the next traversal. Since we don't 164 * actually enter the directory until after the preorder visit, set 165 * the fts_accpath field specially so the chdir gets done to the right 166 * place and the user can access the first node. From fts_open it's 167 * known that the path will fit. 168 */ 169 len = p->fts_pathlen = p->fts_namelen; 170 bcopy(p->fts_name, sp->fts_path, len + 1); 171 if ((cp = rindex(p->fts_name, '/')) && (cp != p->fts_name || cp[1])) { 172 len = strlen(++cp); 173 bcopy(cp, p->fts_name, len + 1); 174 p->fts_namelen = len; 175 } 176 p->fts_accpath = p->fts_path = sp->fts_path; 177 sp->fts_dev = p->fts_dev; 178 } 179 180 int 181 fts_close(sp) 182 FTS *sp; 183 { 184 register FTSENT *freep, *p; 185 int saved_errno; 186 187 /* 188 * This still works if we haven't read anything -- the dummy structure 189 * points to the root list, so we step through to the end of the root 190 * list which has a valid parent pointer. 191 */ 192 if (sp->fts_cur) { 193 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 194 freep = p; 195 p = p->fts_link ? p->fts_link : p->fts_parent; 196 free(freep); 197 } 198 free(p); 199 } 200 201 /* Free up child linked list, sort array, path buffer. */ 202 if (sp->fts_child) 203 fts_lfree(sp->fts_child); 204 if (sp->fts_array) 205 free(sp->fts_array); 206 free(sp->fts_path); 207 208 /* Return to original directory, save errno if necessary. */ 209 if (!ISSET(FTS_NOCHDIR)) { 210 saved_errno = fchdir(sp->fts_rfd) ? errno : 0; 211 (void)close(sp->fts_rfd); 212 } 213 214 /* Free up the stream pointer. */ 215 free(sp); 216 217 /* Set errno and return. */ 218 if (!ISSET(FTS_NOCHDIR) && saved_errno) { 219 errno = saved_errno; 220 return (-1); 221 } 222 return (0); 223 } 224 225 /* 226 * Special case a root of "/" so that slashes aren't appended which would 227 * cause paths to be written as "//foo". 228 */ 229 #define NAPPEND(p) \ 230 (p->fts_level == FTS_ROOTLEVEL && p->fts_pathlen == 1 && \ 231 p->fts_path[0] == '/' ? 0 : p->fts_pathlen) 232 233 FTSENT * 234 fts_read(sp) 235 register FTS *sp; 236 { 237 register FTSENT *p, *tmp; 238 register int instr; 239 register char *t; 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 got 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, reading it if haven't already. If 300 * the read fails for any reason, or the directory is empty, 301 * the fts_info field of the current node is set by fts_build. 302 * If have already read and now fail to chdir, whack the list 303 * to make the names come out right, and set the parent state 304 * so the application will eventually get an error condition. 305 * If haven't read and fail to chdir, check to see if we're 306 * at the root node -- if so, we have to get back or the root 307 * node may be inaccessible. 308 */ 309 if (sp->fts_child) { 310 if (CHDIR(sp, p->fts_accpath)) { 311 p->fts_errno = errno; 312 p->fts_flags |= FTS_DONTCHDIR; 313 for (p = sp->fts_child; p; p = p->fts_link) 314 p->fts_accpath = 315 p->fts_parent->fts_accpath; 316 } 317 } else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) { 318 p->fts_flags |= FTS_DONTCHDIR; 319 if (ISSET(FTS_STOP)) 320 return (NULL); 321 if (p->fts_level == FTS_ROOTLEVEL && 322 FCHDIR(sp, sp->fts_rfd)) { 323 (void)close(sp->fts_rfd); 324 SET(FTS_STOP); 325 return (NULL); 326 } 327 (void)close(sp->fts_rfd); 328 return (p); 329 } 330 p = sp->fts_child; 331 sp->fts_child = NULL; 332 goto name; 333 } 334 335 /* Move to the next node on this level. */ 336 next: tmp = p; 337 if (p = p->fts_link) { 338 free(tmp); 339 340 /* If reached the top, load the paths for the next root. */ 341 if (p->fts_level == FTS_ROOTLEVEL) { 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 sp->fts_path[p->fts_pathlen] = '\0'; 386 387 /* 388 * Change to starting directory. If at a root node or came through a 389 * symlink, go back through the file descriptor. Otherwise, just cd 390 * up one directory. 391 */ 392 if (p->fts_level == FTS_ROOTLEVEL) { 393 if (FCHDIR(sp, sp->fts_rfd)) { 394 (void)close(sp->fts_rfd); 395 SET(FTS_STOP); 396 return (NULL); 397 } 398 (void)close(sp->fts_rfd); 399 } else if (p->fts_flags & FTS_SYMFOLLOW) { 400 if (FCHDIR(sp, p->fts_symfd)) { 401 (void)close(p->fts_symfd); 402 SET(FTS_STOP); 403 return (NULL); 404 } 405 (void)close(p->fts_symfd); 406 } else if (!(p->fts_flags & FTS_DONTCHDIR)) { 407 if (CHDIR(sp, "..")) { 408 SET(FTS_STOP); 409 return (NULL); 410 } 411 } 412 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 413 return (sp->fts_cur = p); 414 } 415 416 /* 417 * Fts_set takes the stream as an argument although it's not used in this 418 * implementation; it would be necessary if anyone wanted to add global 419 * semantics to fts using fts_set. An error return is allowed for similar 420 * reasons. 421 */ 422 /* ARGSUSED */ 423 int 424 fts_set(sp, p, instr) 425 FTS *sp; 426 FTSENT *p; 427 int instr; 428 { 429 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW && 430 instr != FTS_NOINSTR && instr != FTS_SKIP) { 431 errno = EINVAL; 432 return (1); 433 } 434 p->fts_instr = instr; 435 return (0); 436 } 437 438 FTSENT * 439 fts_children(sp, instr) 440 register FTS *sp; 441 int instr; 442 { 443 register FTSENT *p; 444 int fd; 445 446 if (instr && instr != FTS_NAMEONLY) { 447 errno = EINVAL; 448 return (NULL); 449 } 450 451 /* Set current node pointer. */ 452 p = sp->fts_cur; 453 454 /* 455 * Errno set to 0 so user can distinguish empty directory from 456 * an error. 457 */ 458 errno = 0; 459 460 /* Fatal errors stop here. */ 461 if (ISSET(FTS_STOP)) 462 return (NULL); 463 464 /* Return logical hierarchy of user's arguments. */ 465 if (p->fts_info == FTS_INIT) 466 return (p->fts_link); 467 468 /* 469 * If not a directory being visited in pre-order, stop here. Could 470 * allow FTS_DNR, assuming the user has fixed the problem, but the 471 * same effect is available with FTS_AGAIN. 472 */ 473 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 474 return (NULL); 475 476 /* Free up any previous child list. */ 477 if (sp->fts_child) 478 fts_lfree(sp->fts_child); 479 480 if (instr == FTS_NAMEONLY) { 481 sp->fts_options |= FTS_NAMEONLY; 482 instr = BNAMES; 483 } else 484 instr = BCHILD; 485 486 /* 487 * If using chdir on a relative path and called BEFORE fts_read does 488 * its chdir to the root of a traversal, we can lose -- we need to 489 * chdir into the subdirectory, and we don't know where the current 490 * directory is, so we can't get back so that the upcoming chdir by 491 * fts_read will work. 492 */ 493 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 494 ISSET(FTS_NOCHDIR)) 495 return (sp->fts_child = fts_build(sp, instr)); 496 497 if ((fd = open(".", O_RDONLY, 0)) < 0) 498 return (NULL); 499 sp->fts_child = fts_build(sp, instr); 500 if (fchdir(fd)) 501 return (NULL); 502 (void)close(fd); 503 return (sp->fts_child); 504 } 505 506 /* 507 * This is the tricky part -- do not casually change *anything* in here. The 508 * idea is to build the linked list of entries that are used by fts_children 509 * and fts_read. There are lots of special cases. 510 * 511 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 512 * set and it's a physical walk (so that symbolic links can't be directories), 513 * we assume that the number of subdirectories in a node is equal to the number 514 * of links to the parent. This allows stat calls to be skipped in any leaf 515 * directories and for any nodes after the directories in the parent node have 516 * been found. This empirically cuts the stat calls by about 2/3. 517 */ 518 static FTSENT * 519 fts_build(sp, type) 520 register FTS *sp; 521 int type; 522 { 523 register struct dirent *dp; 524 register FTSENT *p, *head; 525 register int nitems; 526 FTSENT *cur, *tail; 527 DIR *dirp; 528 void *adjaddr; 529 int cderrno, descend, len, level, maxlen, nlinks, saved_errno; 530 char *cp; 531 532 /* Set current node pointer. */ 533 cur = sp->fts_cur; 534 535 /* 536 * Open the directory for reading. If this fails, we're done. 537 * If being called from fts_read, set the fts_info field. 538 */ 539 if ((dirp = opendir(cur->fts_accpath)) == NULL) { 540 if (type == BREAD) { 541 cur->fts_info = FTS_DNR; 542 cur->fts_errno = errno; 543 } 544 return (NULL); 545 } 546 547 /* 548 * Nlinks is the number of possible entries of type directory in the 549 * directory if we're cheating on stat calls, 0 if we're not doing 550 * any stat calls at all, -1 if we're doing stats on everything. 551 */ 552 if (type == BNAMES) 553 nlinks = 0; 554 else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) 555 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 556 else 557 nlinks = -1; 558 559 #ifdef notdef 560 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 561 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 562 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 563 #endif 564 /* 565 * If we're going to need to stat anything or we want to descend 566 * and stay in the directory, chdir. If this fails we keep going. 567 * We won't be able to stat anything, but we can still return the 568 * names themselves. Note, that since fts_read won't be able to 569 * chdir into the directory, it will have to return different path 570 * names than before, i.e. "a/b" instead of "b". Since the node 571 * has already been visited in pre-order, have to wait until the 572 * post-order visit to return the error. There is a special case 573 * here, if there was nothing to stat then it's not an error to 574 * not be able to stat. This is all fairly nasty. If a program 575 * needed sorted entries or stat information, they had better be 576 * checking FTS_NS on the returned nodes. 577 */ 578 if (nlinks || type == BREAD) 579 if (FCHDIR(sp, dirfd(dirp))) { 580 if (nlinks && type == BREAD) 581 cur->fts_errno = errno; 582 descend = 0; 583 cderrno = errno; 584 } else { 585 descend = 1; 586 cderrno = 0; 587 } 588 else 589 descend = 0; 590 591 /* 592 * Figure out the max file name length that can be stored in the 593 * current path -- the inner loop allocates more path as necessary. 594 * We really wouldn't have to do the maxlen calculations here, we 595 * could do them in fts_read before returning the path, but it's a 596 * lot easier here since the length is part of the dirent structure. 597 * 598 * If not changing directories set a pointer so that can just append 599 * each new name into the path. 600 */ 601 maxlen = sp->fts_pathlen - cur->fts_pathlen - 1; 602 len = NAPPEND(cur); 603 if (ISSET(FTS_NOCHDIR)) { 604 cp = sp->fts_path + len; 605 *cp++ = '/'; 606 } 607 608 level = cur->fts_level + 1; 609 610 /* Read the directory, attaching each entry to the `link' pointer. */ 611 adjaddr = NULL; 612 for (head = tail = NULL, nitems = 0; dp = readdir(dirp);) { 613 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 614 continue; 615 616 if ((p = fts_alloc(sp, dp->d_name, (int)dp->d_namlen)) == NULL) 617 goto mem1; 618 if (dp->d_namlen > maxlen) { 619 if (fts_palloc(sp, (int)dp->d_namlen)) { 620 /* 621 * No more memory for path or structures. Save 622 * errno, free up the current structure and the 623 * structures already allocated. 624 */ 625 mem1: saved_errno = errno; 626 if (p) 627 free(p); 628 fts_lfree(head); 629 (void)closedir(dirp); 630 errno = saved_errno; 631 cur->fts_info = FTS_ERR; 632 SET(FTS_STOP); 633 return (NULL); 634 } 635 adjaddr = sp->fts_path; 636 maxlen = sp->fts_pathlen - sp->fts_cur->fts_pathlen - 1; 637 } 638 639 p->fts_pathlen = len + dp->d_namlen + 1; 640 p->fts_parent = sp->fts_cur; 641 p->fts_level = level; 642 643 if (cderrno) { 644 if (nlinks) { 645 p->fts_info = FTS_NS; 646 p->fts_errno = cderrno; 647 } else 648 p->fts_info = FTS_NSOK; 649 p->fts_accpath = cur->fts_accpath; 650 } else if (nlinks) { 651 /* Build a file name for fts_stat to stat. */ 652 if (ISSET(FTS_NOCHDIR)) { 653 p->fts_accpath = p->fts_path; 654 bcopy(p->fts_name, cp, p->fts_namelen + 1); 655 } else 656 p->fts_accpath = p->fts_name; 657 p->fts_info = fts_stat(sp, p, 0); 658 if (nlinks > 0 && (p->fts_info == FTS_D || 659 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 660 --nlinks; 661 } else { 662 p->fts_accpath = 663 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 664 p->fts_info = FTS_NSOK; 665 } 666 667 /* We walk in directory order so "ls -f" doesn't get upset. */ 668 p->fts_link = NULL; 669 if (head == NULL) 670 head = tail = p; 671 else { 672 tail->fts_link = p; 673 tail = p; 674 } 675 ++nitems; 676 } 677 (void)closedir(dirp); 678 679 /* 680 * If had to realloc the path, adjust the addresses for the rest 681 * of the tree. 682 */ 683 if (adjaddr) 684 fts_padjust(sp, adjaddr); 685 686 /* 687 * If not changing directories, reset the path back to original 688 * state. 689 */ 690 if (ISSET(FTS_NOCHDIR)) { 691 if (cp - 1 > sp->fts_path) 692 --cp; 693 *cp = '\0'; 694 } 695 696 /* 697 * If descended after called from fts_children or called from 698 * fts_read and didn't find anything, get back. If can't get 699 * back, done. 700 */ 701 if (descend && (!nitems || type == BCHILD) && CHDIR(sp, "..")) { 702 cur->fts_info = FTS_ERR; 703 SET(FTS_STOP); 704 return (NULL); 705 } 706 707 /* If didn't find anything, just do the post-order visit */ 708 if (!nitems) { 709 if (type == BREAD) 710 cur->fts_info = FTS_DP; 711 return (NULL); 712 } 713 714 /* Sort the entries. */ 715 if (sp->fts_compar && nitems > 1) 716 head = fts_sort(sp, head, nitems); 717 return (head); 718 } 719 720 static u_short 721 fts_stat(sp, p, follow) 722 FTS *sp; 723 register FTSENT *p; 724 int follow; 725 { 726 register FTSENT *t; 727 register dev_t dev; 728 register ino_t ino; 729 struct stat *sbp, sb; 730 int saved_errno; 731 732 /* If user needs stat info, stat buffer already allocated. */ 733 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 734 735 /* 736 * If doing a logical walk, or application requested FTS_FOLLOW, do 737 * a stat(2). If that fails, check for a non-existent symlink. If 738 * fail, set the errno from the stat call. 739 */ 740 if (ISSET(FTS_LOGICAL) || follow) { 741 if (stat(p->fts_accpath, sbp)) { 742 saved_errno = errno; 743 if (!lstat(p->fts_accpath, sbp)) { 744 errno = 0; 745 return (FTS_SLNONE); 746 } 747 p->fts_errno = saved_errno; 748 goto err; 749 } 750 } else if (lstat(p->fts_accpath, sbp)) { 751 p->fts_errno = errno; 752 err: bzero(sbp, sizeof(struct stat)); 753 return (FTS_NS); 754 } 755 756 if (S_ISDIR(sbp->st_mode)) { 757 /* 758 * Set the device/inode. Used to find cycles and check for 759 * crossing mount points. Also remember the link count, used 760 * in fts_build to limit the number of stat calls. It is 761 * understood that these fields are only referenced if fts_info 762 * is set to FTS_D. 763 */ 764 dev = p->fts_dev = sbp->st_dev; 765 ino = p->fts_ino = sbp->st_ino; 766 p->fts_nlink = sbp->st_nlink; 767 768 if (ISDOT(p->fts_name)) 769 return (FTS_DOT); 770 771 /* 772 * Cycle detection is done by brute force when the directory 773 * is first encountered. If the tree gets deep enough or the 774 * number of symbolic links to directories is high enough, 775 * something faster might be worthwhile. 776 */ 777 for (t = p->fts_parent; 778 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 779 if (ino == t->fts_ino && dev == t->fts_dev) { 780 p->fts_cycle = t; 781 return (FTS_DC); 782 } 783 return (FTS_D); 784 } 785 if (S_ISLNK(sbp->st_mode)) 786 return (FTS_SL); 787 if (S_ISREG(sbp->st_mode)) 788 return (FTS_F); 789 return (FTS_DEFAULT); 790 } 791 792 static FTSENT * 793 fts_sort(sp, head, nitems) 794 FTS *sp; 795 FTSENT *head; 796 register int nitems; 797 { 798 register FTSENT **ap, *p; 799 800 /* 801 * Construct an array of pointers to the structures and call qsort(3). 802 * Reassemble the array in the order returned by qsort. If unable to 803 * sort for memory reasons, return the directory entries in their 804 * current order. Allocate enough space for the current needs plus 805 * 40 so don't realloc one entry at a time. 806 */ 807 if (nitems > sp->fts_nitems) { 808 sp->fts_nitems = nitems + 40; 809 if ((sp->fts_array = realloc(sp->fts_array, 810 (size_t)(sp->fts_nitems * sizeof(FTSENT *)))) == NULL) { 811 sp->fts_nitems = 0; 812 return (head); 813 } 814 } 815 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 816 *ap++ = p; 817 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), sp->fts_compar); 818 for (head = *(ap = sp->fts_array); --nitems; ++ap) 819 ap[0]->fts_link = ap[1]; 820 ap[0]->fts_link = NULL; 821 return (head); 822 } 823 824 static FTSENT * 825 fts_alloc(sp, name, len) 826 FTS *sp; 827 char *name; 828 register int len; 829 { 830 register FTSENT *p; 831 int needstat; 832 833 /* 834 * Variable sized structures. The stat structure isn't necessary 835 * if the user doesn't need it, and the name is variable length. 836 * Allocate enough extra space after the structure to store them. 837 */ 838 needstat = ISSET(FTS_NOSTAT) ? 0 : ALIGN(sizeof(struct stat)); 839 if ((p = malloc((size_t)(sizeof(FTSENT) + len + 1 + needstat))) == NULL) 840 return (NULL); 841 bcopy(name, p->fts_name, len + 1); 842 if (needstat) 843 p->fts_statp = (struct stat *)ALIGN(p->fts_name + len + 1); 844 p->fts_namelen = len; 845 p->fts_path = sp->fts_path; 846 p->fts_errno = 0; 847 p->fts_flags = 0; 848 p->fts_instr = FTS_NOINSTR; 849 p->fts_number = 0; 850 #ifdef NOT_NECESSARY 851 p->fts_pointer = NULL; 852 #endif 853 return (p); 854 } 855 856 static void 857 fts_lfree(head) 858 register FTSENT *head; 859 { 860 register FTSENT *p; 861 862 /* Free a linked list of structures. */ 863 while (p = head) { 864 head = head->fts_link; 865 free(p); 866 } 867 } 868 869 /* 870 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 871 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 872 * though the kernel won't resolve them. Add the size (not just what's needed) 873 * plus 256 bytes so don't realloc the path 2 bytes at a time. 874 */ 875 static int 876 fts_palloc(sp, more) 877 FTS *sp; 878 int more; 879 { 880 881 sp->fts_pathlen += more + 256; 882 sp->fts_path = realloc(sp->fts_path, (size_t)sp->fts_pathlen); 883 return (sp->fts_path == NULL); 884 } 885 886 /* 887 * When the path is realloc'd, have to fix all of the pointers in structures 888 * already returned. 889 */ 890 static void 891 fts_padjust(sp, addr) 892 FTS *sp; 893 void *addr; 894 { 895 FTSENT *p; 896 897 #define ADJUST(p) { \ 898 (p)->fts_accpath = addr + ((p)->fts_accpath - (p)->fts_path); \ 899 (p)->fts_path = addr; \ 900 } 901 /* Adjust the current set of children. */ 902 for (p = sp->fts_child; p; p = p->fts_link) 903 ADJUST(p); 904 905 /* Adjust the rest of the tree. */ 906 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 907 ADJUST(p); 908 p = p->fts_link ? p->fts_link : p->fts_parent; 909 } 910 } 911