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 5.34 (Berkeley) 03/20/92"; 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 int saved_errno; 241 242 /* If finished or unrecoverable error, return NULL. */ 243 if (sp->fts_cur == NULL || ISSET(FTS_STOP)) 244 return (NULL); 245 246 /* Set current node pointer. */ 247 p = sp->fts_cur; 248 249 /* Save and zero out user instructions. */ 250 instr = p->fts_instr; 251 p->fts_instr = FTS_NOINSTR; 252 253 /* Any type of file may be re-visited; re-stat and re-turn. */ 254 if (instr == FTS_AGAIN) { 255 p->fts_info = fts_stat(sp, p, 0); 256 return (p); 257 } 258 259 /* 260 * Following a symlink -- SLNONE test allows application to see 261 * SLNONE and recover. If indirecting through a symlink, have 262 * keep a pointer to current location. If unable to get that 263 * pointer, follow fails. 264 */ 265 if (instr == FTS_FOLLOW && 266 (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) { 267 p->fts_info = fts_stat(sp, p, 1); 268 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) 269 if ((p->fts_symfd = open(".", O_RDONLY, 0)) < 0) { 270 p->fts_errno = errno; 271 p->fts_info = FTS_ERR; 272 } else 273 p->fts_flags |= FTS_SYMFOLLOW; 274 return (p); 275 } 276 277 /* Directory in pre-order. */ 278 if (p->fts_info == FTS_D) { 279 /* If skipped or crossed mount point, do post-order visit. */ 280 if (instr == FTS_SKIP || 281 ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev) { 282 if (p->fts_flags & FTS_SYMFOLLOW) 283 (void)close(p->fts_symfd); 284 if (sp->fts_child) { 285 fts_lfree(sp->fts_child); 286 sp->fts_child = NULL; 287 } 288 p->fts_info = FTS_DP; 289 return (p); 290 } 291 292 /* Rebuild if only got the names and now traversing. */ 293 if (sp->fts_child && sp->fts_options & FTS_NAMEONLY) { 294 sp->fts_options &= ~FTS_NAMEONLY; 295 fts_lfree(sp->fts_child); 296 sp->fts_child = NULL; 297 } 298 299 /* 300 * Cd to the subdirectory, reading it if haven't already. If 301 * the read fails for any reason, or the directory is empty, 302 * the fts_info field of the current node is set by fts_build. 303 * If have already read and now fail to chdir, whack the list 304 * to make the names come out right, and set the parent state 305 * so the application will eventually get an error condition. 306 * If haven't read and fail to chdir, check to see if we're 307 * at the root node -- if so, we have to get back or the root 308 * node may be inaccessible. 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 if (p->fts_level == FTS_ROOTLEVEL && 322 !ISSET(FTS_NOCHDIR) && FCHDIR(sp, sp->fts_rfd)) { 323 saved_errno = errno; 324 (void)close(sp->fts_rfd); 325 errno = saved_errno; 326 SET(FTS_STOP); 327 return (NULL); 328 } 329 p->fts_flags |= FTS_DONTCHDIR; 330 p->fts_info = FTS_DP; 331 return (p); 332 } 333 p = sp->fts_child; 334 sp->fts_child = NULL; 335 goto name; 336 } 337 338 /* Move to the next node on this level. */ 339 next: tmp = p; 340 if (p = p->fts_link) { 341 free(tmp); 342 343 /* If reached the top, load the paths for the next root. */ 344 if (p->fts_level == FTS_ROOTLEVEL) { 345 fts_load(sp, p); 346 return (sp->fts_cur = p); 347 } 348 349 /* 350 * User may have called fts_set on the node. If skipped, 351 * ignore. If followed, get a file descriptor so we can 352 * get back if necessary. 353 */ 354 if (p->fts_instr == FTS_SKIP) 355 goto next; 356 if (p->fts_instr == FTS_FOLLOW) { 357 p->fts_info = fts_stat(sp, p, 1); 358 if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) 359 if ((p->fts_symfd = 360 open(".", O_RDONLY, 0)) < 0) { 361 p->fts_errno = errno; 362 p->fts_info = FTS_ERR; 363 } else 364 p->fts_flags |= FTS_SYMFOLLOW; 365 p->fts_instr = FTS_NOINSTR; 366 } 367 368 name: t = sp->fts_path + NAPPEND(p->fts_parent); 369 *t++ = '/'; 370 bcopy(p->fts_name, t, p->fts_namelen + 1); 371 return (sp->fts_cur = p); 372 } 373 374 /* Move up to the parent node. */ 375 p = tmp->fts_parent; 376 free(tmp); 377 378 if (p->fts_level == FTS_ROOTPARENTLEVEL) { 379 /* 380 * Done; free everything up and set errno to 0 so the user 381 * can distinguish between error and EOF. 382 */ 383 free(p); 384 errno = 0; 385 return (sp->fts_cur = NULL); 386 } 387 388 sp->fts_path[p->fts_pathlen] = '\0'; 389 390 /* 391 * Change to starting directory. If at a root node or came through a 392 * symlink, go back through the file descriptor. Otherwise, just cd 393 * up one directory. 394 */ 395 if (p->fts_level == FTS_ROOTLEVEL) { 396 if (FCHDIR(sp, sp->fts_rfd)) { 397 saved_errno = errno; 398 (void)close(sp->fts_rfd); 399 errno = saved_errno; 400 SET(FTS_STOP); 401 return (NULL); 402 } 403 (void)close(sp->fts_rfd); 404 } else if (p->fts_flags & FTS_SYMFOLLOW) { 405 if (FCHDIR(sp, p->fts_symfd)) { 406 saved_errno = errno; 407 (void)close(p->fts_symfd); 408 errno = saved_errno; 409 SET(FTS_STOP); 410 return (NULL); 411 } 412 (void)close(p->fts_symfd); 413 } else if (!(p->fts_flags & FTS_DONTCHDIR)) { 414 if (CHDIR(sp, "..")) { 415 SET(FTS_STOP); 416 return (NULL); 417 } 418 } 419 p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP; 420 return (sp->fts_cur = p); 421 } 422 423 /* 424 * Fts_set takes the stream as an argument although it's not used in this 425 * implementation; it would be necessary if anyone wanted to add global 426 * semantics to fts using fts_set. An error return is allowed for similar 427 * reasons. 428 */ 429 /* ARGSUSED */ 430 int 431 fts_set(sp, p, instr) 432 FTS *sp; 433 FTSENT *p; 434 int instr; 435 { 436 if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW && 437 instr != FTS_NOINSTR && instr != FTS_SKIP) { 438 errno = EINVAL; 439 return (1); 440 } 441 p->fts_instr = instr; 442 return (0); 443 } 444 445 FTSENT * 446 fts_children(sp, instr) 447 register FTS *sp; 448 int instr; 449 { 450 register FTSENT *p; 451 int fd; 452 453 if (instr && instr != FTS_NAMEONLY) { 454 errno = EINVAL; 455 return (NULL); 456 } 457 458 /* Set current node pointer. */ 459 p = sp->fts_cur; 460 461 /* 462 * Errno set to 0 so user can distinguish empty directory from 463 * an error. 464 */ 465 errno = 0; 466 467 /* Fatal errors stop here. */ 468 if (ISSET(FTS_STOP)) 469 return (NULL); 470 471 /* Return logical hierarchy of user's arguments. */ 472 if (p->fts_info == FTS_INIT) 473 return (p->fts_link); 474 475 /* 476 * If not a directory being visited in pre-order, stop here. Could 477 * allow FTS_DNR, assuming the user has fixed the problem, but the 478 * same effect is available with FTS_AGAIN. 479 */ 480 if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */) 481 return (NULL); 482 483 /* Free up any previous child list. */ 484 if (sp->fts_child) 485 fts_lfree(sp->fts_child); 486 487 if (instr == FTS_NAMEONLY) { 488 sp->fts_options |= FTS_NAMEONLY; 489 instr = BNAMES; 490 } else 491 instr = BCHILD; 492 493 /* 494 * If using chdir on a relative path and called BEFORE fts_read does 495 * its chdir to the root of a traversal, we can lose -- we need to 496 * chdir into the subdirectory, and we don't know where the current 497 * directory is, so we can't get back so that the upcoming chdir by 498 * fts_read will work. 499 */ 500 if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '/' || 501 ISSET(FTS_NOCHDIR)) 502 return (sp->fts_child = fts_build(sp, instr)); 503 504 if ((fd = open(".", O_RDONLY, 0)) < 0) 505 return (NULL); 506 sp->fts_child = fts_build(sp, instr); 507 if (fchdir(fd)) 508 return (NULL); 509 (void)close(fd); 510 return (sp->fts_child); 511 } 512 513 /* 514 * This is the tricky part -- do not casually change *anything* in here. The 515 * idea is to build the linked list of entries that are used by fts_children 516 * and fts_read. There are lots of special cases. 517 * 518 * The real slowdown in walking the tree is the stat calls. If FTS_NOSTAT is 519 * set and it's a physical walk (so that symbolic links can't be directories), 520 * we assume that the number of subdirectories in a node is equal to the number 521 * of links to the parent. This allows stat calls to be skipped in any leaf 522 * directories and for any nodes after the directories in the parent node have 523 * been found. This empirically cuts the stat calls by about 2/3. 524 */ 525 static FTSENT * 526 fts_build(sp, type) 527 register FTS *sp; 528 int type; 529 { 530 register struct dirent *dp; 531 register FTSENT *p, *head; 532 register int nitems; 533 FTSENT *cur, *tail; 534 DIR *dirp; 535 void *adjaddr; 536 int cderrno, descend, len, level, maxlen, nlinks, saved_errno; 537 char *cp; 538 539 /* Set current node pointer. */ 540 cur = sp->fts_cur; 541 542 /* 543 * Open the directory for reading. If this fails, we're done. 544 * If being called from fts_read, set the fts_info field. 545 */ 546 if ((dirp = opendir(cur->fts_accpath)) == NULL) { 547 if (type == BREAD) { 548 cur->fts_info = FTS_DNR; 549 cur->fts_errno = errno; 550 } 551 return (NULL); 552 } 553 554 /* 555 * Nlinks is the number of possible entries of type directory in the 556 * directory if we're cheating on stat calls, 0 if we're not doing 557 * any stat calls at all, -1 if we're doing stats on everything. 558 */ 559 if (type == BNAMES) 560 nlinks = 0; 561 else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) 562 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 563 else 564 nlinks = -1; 565 566 #ifdef notdef 567 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 568 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 569 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 570 #endif 571 /* 572 * If we're going to need to stat anything or we want to descend 573 * and stay in the directory, chdir. If this fails we keep going. 574 * We won't be able to stat anything, but we can still return the 575 * names themselves. Note, that since fts_read won't be able to 576 * chdir into the directory, it will have to return different path 577 * names than before, i.e. "a/b" instead of "b". Since the node 578 * has already been visited in pre-order, have to wait until the 579 * post-order visit to return the error. There is a special case 580 * here, if there was nothing to stat then it's not an error to 581 * not be able to stat. This is all fairly nasty. If a program 582 * needed sorted entries or stat information, they had better be 583 * checking FTS_NS on the returned nodes. 584 */ 585 if (nlinks || type == BREAD) 586 if (FCHDIR(sp, dirfd(dirp))) { 587 if (nlinks && type == BREAD) 588 cur->fts_errno = errno; 589 descend = 0; 590 cderrno = errno; 591 } else { 592 descend = 1; 593 cderrno = 0; 594 } 595 else 596 descend = 0; 597 598 /* 599 * Figure out the max file name length that can be stored in the 600 * current path -- the inner loop allocates more path as necessary. 601 * We really wouldn't have to do the maxlen calculations here, we 602 * could do them in fts_read before returning the path, but it's a 603 * lot easier here since the length is part of the dirent structure. 604 * 605 * If not changing directories set a pointer so that can just append 606 * each new name into the path. 607 */ 608 maxlen = sp->fts_pathlen - cur->fts_pathlen - 1; 609 len = NAPPEND(cur); 610 if (ISSET(FTS_NOCHDIR)) { 611 cp = sp->fts_path + len; 612 *cp++ = '/'; 613 } 614 615 level = cur->fts_level + 1; 616 617 /* Read the directory, attaching each entry to the `link' pointer. */ 618 adjaddr = NULL; 619 for (head = tail = NULL, nitems = 0; dp = readdir(dirp);) { 620 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 621 continue; 622 623 if ((p = fts_alloc(sp, dp->d_name, (int)dp->d_namlen)) == NULL) 624 goto mem1; 625 if (dp->d_namlen > maxlen) { 626 if (fts_palloc(sp, (int)dp->d_namlen)) { 627 /* 628 * No more memory for path or structures. Save 629 * errno, free up the current structure and the 630 * structures already allocated. 631 */ 632 mem1: saved_errno = errno; 633 if (p) 634 free(p); 635 fts_lfree(head); 636 (void)closedir(dirp); 637 errno = saved_errno; 638 cur->fts_info = FTS_ERR; 639 SET(FTS_STOP); 640 return (NULL); 641 } 642 adjaddr = sp->fts_path; 643 maxlen = sp->fts_pathlen - sp->fts_cur->fts_pathlen - 1; 644 } 645 646 p->fts_pathlen = len + dp->d_namlen + 1; 647 p->fts_parent = sp->fts_cur; 648 p->fts_level = level; 649 650 if (cderrno) { 651 if (nlinks) { 652 p->fts_info = FTS_NS; 653 p->fts_errno = cderrno; 654 } else 655 p->fts_info = FTS_NSOK; 656 p->fts_accpath = cur->fts_accpath; 657 } else if (nlinks) { 658 /* Build a file name for fts_stat to stat. */ 659 if (ISSET(FTS_NOCHDIR)) { 660 p->fts_accpath = p->fts_path; 661 bcopy(p->fts_name, cp, p->fts_namelen + 1); 662 } else 663 p->fts_accpath = p->fts_name; 664 p->fts_info = fts_stat(sp, p, 0); 665 if (nlinks > 0 && (p->fts_info == FTS_D || 666 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 667 --nlinks; 668 } else { 669 p->fts_accpath = 670 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 671 p->fts_info = FTS_NSOK; 672 } 673 674 /* We walk in directory order so "ls -f" doesn't get upset. */ 675 p->fts_link = NULL; 676 if (head == NULL) 677 head = tail = p; 678 else { 679 tail->fts_link = p; 680 tail = p; 681 } 682 ++nitems; 683 } 684 (void)closedir(dirp); 685 686 /* 687 * If had to realloc the path, adjust the addresses for the rest 688 * of the tree. 689 */ 690 if (adjaddr) 691 fts_padjust(sp, adjaddr); 692 693 /* 694 * If not changing directories, reset the path back to original 695 * state. 696 */ 697 if (ISSET(FTS_NOCHDIR)) { 698 if (cp - 1 > sp->fts_path) 699 --cp; 700 *cp = '\0'; 701 } 702 703 /* 704 * If descended after called from fts_children or called from 705 * fts_read and didn't find anything, get back. If can't get 706 * back, done. 707 */ 708 if (descend && (!nitems || type == BCHILD) && CHDIR(sp, "..")) { 709 cur->fts_info = FTS_ERR; 710 SET(FTS_STOP); 711 return (NULL); 712 } 713 714 /* If didn't find anything, return NULL. */ 715 if (!nitems) 716 return (NULL); 717 718 /* Sort the entries. */ 719 if (sp->fts_compar && nitems > 1) 720 head = fts_sort(sp, head, nitems); 721 return (head); 722 } 723 724 static u_short 725 fts_stat(sp, p, follow) 726 FTS *sp; 727 register FTSENT *p; 728 int follow; 729 { 730 register FTSENT *t; 731 register dev_t dev; 732 register ino_t ino; 733 struct stat *sbp, sb; 734 int saved_errno; 735 736 /* If user needs stat info, stat buffer already allocated. */ 737 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 738 739 /* 740 * If doing a logical walk, or application requested FTS_FOLLOW, do 741 * a stat(2). If that fails, check for a non-existent symlink. If 742 * fail, set the errno from the stat call. 743 */ 744 if (ISSET(FTS_LOGICAL) || follow) { 745 if (stat(p->fts_accpath, sbp)) { 746 saved_errno = errno; 747 if (!lstat(p->fts_accpath, sbp)) { 748 errno = 0; 749 return (FTS_SLNONE); 750 } 751 p->fts_errno = saved_errno; 752 goto err; 753 } 754 } else if (lstat(p->fts_accpath, sbp)) { 755 p->fts_errno = errno; 756 err: bzero(sbp, sizeof(struct stat)); 757 return (FTS_NS); 758 } 759 760 if (S_ISDIR(sbp->st_mode)) { 761 /* 762 * Set the device/inode. Used to find cycles and check for 763 * crossing mount points. Also remember the link count, used 764 * in fts_build to limit the number of stat calls. It is 765 * understood that these fields are only referenced if fts_info 766 * is set to FTS_D. 767 */ 768 dev = p->fts_dev = sbp->st_dev; 769 ino = p->fts_ino = sbp->st_ino; 770 p->fts_nlink = sbp->st_nlink; 771 772 if (ISDOT(p->fts_name)) 773 return (FTS_DOT); 774 775 /* 776 * Cycle detection is done by brute force when the directory 777 * is first encountered. If the tree gets deep enough or the 778 * number of symbolic links to directories is high enough, 779 * something faster might be worthwhile. 780 */ 781 for (t = p->fts_parent; 782 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 783 if (ino == t->fts_ino && dev == t->fts_dev) { 784 p->fts_cycle = t; 785 return (FTS_DC); 786 } 787 return (FTS_D); 788 } 789 if (S_ISLNK(sbp->st_mode)) 790 return (FTS_SL); 791 if (S_ISREG(sbp->st_mode)) 792 return (FTS_F); 793 return (FTS_DEFAULT); 794 } 795 796 static FTSENT * 797 fts_sort(sp, head, nitems) 798 FTS *sp; 799 FTSENT *head; 800 register int nitems; 801 { 802 register FTSENT **ap, *p; 803 804 /* 805 * Construct an array of pointers to the structures and call qsort(3). 806 * Reassemble the array in the order returned by qsort. If unable to 807 * sort for memory reasons, return the directory entries in their 808 * current order. Allocate enough space for the current needs plus 809 * 40 so don't realloc one entry at a time. 810 */ 811 if (nitems > sp->fts_nitems) { 812 sp->fts_nitems = nitems + 40; 813 if ((sp->fts_array = realloc(sp->fts_array, 814 (size_t)(sp->fts_nitems * sizeof(FTSENT *)))) == NULL) { 815 sp->fts_nitems = 0; 816 return (head); 817 } 818 } 819 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 820 *ap++ = p; 821 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), sp->fts_compar); 822 for (head = *(ap = sp->fts_array); --nitems; ++ap) 823 ap[0]->fts_link = ap[1]; 824 ap[0]->fts_link = NULL; 825 return (head); 826 } 827 828 static FTSENT * 829 fts_alloc(sp, name, len) 830 FTS *sp; 831 char *name; 832 register int len; 833 { 834 register FTSENT *p; 835 int needstat; 836 837 /* 838 * Variable sized structures. The stat structure isn't necessary 839 * if the user doesn't need it, and the name is variable length. 840 * Allocate enough extra space after the structure to store them. 841 */ 842 needstat = ISSET(FTS_NOSTAT) ? 0 : ALIGN(sizeof(struct stat)); 843 if ((p = malloc((size_t)(sizeof(FTSENT) + len + 1 + needstat))) == NULL) 844 return (NULL); 845 bcopy(name, p->fts_name, len + 1); 846 if (needstat) 847 p->fts_statp = (struct stat *)ALIGN(p->fts_name + len + 1); 848 p->fts_namelen = len; 849 p->fts_path = sp->fts_path; 850 p->fts_errno = 0; 851 p->fts_flags = 0; 852 p->fts_instr = FTS_NOINSTR; 853 p->fts_number = 0; 854 p->fts_pointer = NULL; 855 return (p); 856 } 857 858 static void 859 fts_lfree(head) 860 register FTSENT *head; 861 { 862 register FTSENT *p; 863 864 /* Free a linked list of structures. */ 865 while (p = head) { 866 head = head->fts_link; 867 free(p); 868 } 869 } 870 871 /* 872 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 873 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 874 * though the kernel won't resolve them. Add the size (not just what's needed) 875 * plus 256 bytes so don't realloc the path 2 bytes at a time. 876 */ 877 static int 878 fts_palloc(sp, more) 879 FTS *sp; 880 int more; 881 { 882 883 sp->fts_pathlen += more + 256; 884 sp->fts_path = realloc(sp->fts_path, (size_t)sp->fts_pathlen); 885 return (sp->fts_path == NULL); 886 } 887 888 /* 889 * When the path is realloc'd, have to fix all of the pointers in structures 890 * already returned. 891 */ 892 static void 893 fts_padjust(sp, addr) 894 FTS *sp; 895 void *addr; 896 { 897 FTSENT *p; 898 899 #define ADJUST(p) { \ 900 (p)->fts_accpath = addr + ((p)->fts_accpath - (p)->fts_path); \ 901 (p)->fts_path = addr; \ 902 } 903 /* Adjust the current set of children. */ 904 for (p = sp->fts_child; p; p = p->fts_link) 905 ADJUST(p); 906 907 /* Adjust the rest of the tree. */ 908 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 909 ADJUST(p); 910 p = p->fts_link ? p->fts_link : p->fts_parent; 911 } 912 } 913