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 5.42 (Berkeley) 04/26/93"; 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 can do things quickly. First, if it's a 4.4BSD file system, the type 515 * of the file is in the directory entry. Otherwise, we assume that the number 516 * of subdirectories in a node is equal to the number of links to the parent. 517 * The former skips all stat calls. The latter skips stat calls in any leaf 518 * directories and for any files after the subdirectories in the directory have 519 * been found, cutting the stat calls by about 2/3. 520 */ 521 static FTSENT * 522 fts_build(sp, type) 523 register FTS *sp; 524 int type; 525 { 526 register struct dirent *dp; 527 register FTSENT *p, *head; 528 register int nitems; 529 FTSENT *cur, *tail; 530 DIR *dirp; 531 void *adjaddr; 532 int cderrno, descend, len, level, maxlen, nlinks, saved_errno; 533 char *cp; 534 535 /* Set current node pointer. */ 536 cur = sp->fts_cur; 537 538 /* 539 * Open the directory for reading. If this fails, we're done. 540 * If being called from fts_read, set the fts_info field. 541 */ 542 if ((dirp = opendir(cur->fts_accpath)) == NULL) { 543 if (type == BREAD) { 544 cur->fts_info = FTS_DNR; 545 cur->fts_errno = errno; 546 } 547 return (NULL); 548 } 549 550 /* 551 * Nlinks is the number of possible entries of type directory in the 552 * directory if we're cheating on stat calls, 0 if we're not doing 553 * any stat calls at all, -1 if we're doing stats on everything. 554 */ 555 if (type == BNAMES) 556 nlinks = 0; 557 else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) 558 nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2); 559 else 560 nlinks = -1; 561 562 #ifdef notdef 563 (void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink); 564 (void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n", 565 ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT)); 566 #endif 567 /* 568 * If we're going to need to stat anything or we want to descend 569 * and stay in the directory, chdir. If this fails we keep going, 570 * but set a flag so we don't chdir after the post-order visit. 571 * We won't be able to stat anything, but we can still return the 572 * names themselves. Note, that since fts_read won't be able to 573 * chdir into the directory, it will have to return different path 574 * names than before, i.e. "a/b" instead of "b". Since the node 575 * has already been visited in pre-order, have to wait until the 576 * post-order visit to return the error. There is a special case 577 * here, if there was nothing to stat then it's not an error to 578 * not be able to stat. This is all fairly nasty. If a program 579 * needed sorted entries or stat information, they had better be 580 * checking FTS_NS on the returned nodes. 581 */ 582 cderrno = 0; 583 if (nlinks || type == BREAD) 584 if (FCHDIR(sp, dirfd(dirp))) { 585 if (nlinks && type == BREAD) 586 cur->fts_errno = errno; 587 cur->fts_flags |= FTS_DONTCHDIR; 588 descend = 0; 589 cderrno = errno; 590 } else 591 descend = 1; 592 else 593 descend = 0; 594 595 /* 596 * Figure out the max file name length that can be stored in the 597 * current path -- the inner loop allocates more path as necessary. 598 * We really wouldn't have to do the maxlen calculations here, we 599 * could do them in fts_read before returning the path, but it's a 600 * lot easier here since the length is part of the dirent structure. 601 * 602 * If not changing directories set a pointer so that can just append 603 * each new name into the path. 604 */ 605 maxlen = sp->fts_pathlen - cur->fts_pathlen - 1; 606 len = NAPPEND(cur); 607 if (ISSET(FTS_NOCHDIR)) { 608 cp = sp->fts_path + len; 609 *cp++ = '/'; 610 } 611 612 level = cur->fts_level + 1; 613 614 /* Read the directory, attaching each entry to the `link' pointer. */ 615 adjaddr = NULL; 616 for (head = tail = NULL, nitems = 0; dp = readdir(dirp);) { 617 if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name)) 618 continue; 619 620 if ((p = fts_alloc(sp, dp->d_name, (int)dp->d_namlen)) == NULL) 621 goto mem1; 622 if (dp->d_namlen > maxlen) { 623 if (fts_palloc(sp, (size_t)dp->d_namlen)) { 624 /* 625 * No more memory for path or structures. Save 626 * errno, free up the current structure and the 627 * structures already allocated. 628 */ 629 mem1: saved_errno = errno; 630 if (p) 631 free(p); 632 fts_lfree(head); 633 (void)closedir(dirp); 634 errno = saved_errno; 635 cur->fts_info = FTS_ERR; 636 SET(FTS_STOP); 637 return (NULL); 638 } 639 adjaddr = sp->fts_path; 640 maxlen = sp->fts_pathlen - sp->fts_cur->fts_pathlen - 1; 641 } 642 643 p->fts_pathlen = len + dp->d_namlen + 1; 644 p->fts_parent = sp->fts_cur; 645 p->fts_level = level; 646 647 if (cderrno) { 648 if (nlinks) { 649 p->fts_info = FTS_NS; 650 p->fts_errno = cderrno; 651 } else 652 p->fts_info = FTS_NSOK; 653 p->fts_accpath = cur->fts_accpath; 654 } else if (nlinks == 0 655 #ifdef DT_DIR 656 || nlinks > 0 && 657 dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN 658 #endif 659 ) { 660 p->fts_accpath = 661 ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name; 662 p->fts_info = FTS_NSOK; 663 } else { 664 /* Build a file name for fts_stat to stat. */ 665 if (ISSET(FTS_NOCHDIR)) { 666 p->fts_accpath = p->fts_path; 667 bcopy(p->fts_name, cp, p->fts_namelen + 1); 668 } else 669 p->fts_accpath = p->fts_name; 670 /* Stat it. */ 671 p->fts_info = fts_stat(sp, p, 0); 672 673 /* Decrement link count if applicable. */ 674 if (nlinks > 0 && (p->fts_info == FTS_D || 675 p->fts_info == FTS_DC || p->fts_info == FTS_DOT)) 676 --nlinks; 677 } 678 679 /* We walk in directory order so "ls -f" doesn't get upset. */ 680 p->fts_link = NULL; 681 if (head == NULL) 682 head = tail = p; 683 else { 684 tail->fts_link = p; 685 tail = p; 686 } 687 ++nitems; 688 } 689 (void)closedir(dirp); 690 691 /* 692 * If had to realloc the path, adjust the addresses for the rest 693 * of the tree. 694 */ 695 if (adjaddr) 696 fts_padjust(sp, adjaddr); 697 698 /* 699 * If not changing directories, reset the path back to original 700 * state. 701 */ 702 if (ISSET(FTS_NOCHDIR)) { 703 if (cp - 1 > sp->fts_path) 704 --cp; 705 *cp = '\0'; 706 } 707 708 /* 709 * If descended after called from fts_children or called from 710 * fts_read and didn't find anything, get back. If can't get 711 * back, done. 712 */ 713 if (descend && (!nitems || type == BCHILD) && CHDIR(sp, "..")) { 714 cur->fts_info = FTS_ERR; 715 SET(FTS_STOP); 716 return (NULL); 717 } 718 719 /* If didn't find anything, return NULL. */ 720 if (!nitems) { 721 if (type == BREAD) 722 cur->fts_info = FTS_DP; 723 return (NULL); 724 } 725 726 /* Sort the entries. */ 727 if (sp->fts_compar && nitems > 1) 728 head = fts_sort(sp, head, nitems); 729 return (head); 730 } 731 732 static u_short 733 fts_stat(sp, p, follow) 734 FTS *sp; 735 register FTSENT *p; 736 int follow; 737 { 738 register FTSENT *t; 739 register dev_t dev; 740 register ino_t ino; 741 struct stat *sbp, sb; 742 int saved_errno; 743 744 /* If user needs stat info, stat buffer already allocated. */ 745 sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp; 746 747 /* 748 * If doing a logical walk, or application requested FTS_FOLLOW, do 749 * a stat(2). If that fails, check for a non-existent symlink. If 750 * fail, set the errno from the stat call. 751 */ 752 if (ISSET(FTS_LOGICAL) || follow) { 753 if (stat(p->fts_accpath, sbp)) { 754 saved_errno = errno; 755 if (!lstat(p->fts_accpath, sbp)) { 756 errno = 0; 757 return (FTS_SLNONE); 758 } 759 p->fts_errno = saved_errno; 760 goto err; 761 } 762 } else if (lstat(p->fts_accpath, sbp)) { 763 p->fts_errno = errno; 764 err: bzero(sbp, sizeof(struct stat)); 765 return (FTS_NS); 766 } 767 768 if (S_ISDIR(sbp->st_mode)) { 769 /* 770 * Set the device/inode. Used to find cycles and check for 771 * crossing mount points. Also remember the link count, used 772 * in fts_build to limit the number of stat calls. It is 773 * understood that these fields are only referenced if fts_info 774 * is set to FTS_D. 775 */ 776 dev = p->fts_dev = sbp->st_dev; 777 ino = p->fts_ino = sbp->st_ino; 778 p->fts_nlink = sbp->st_nlink; 779 780 if (ISDOT(p->fts_name)) 781 return (FTS_DOT); 782 783 /* 784 * Cycle detection is done by brute force when the directory 785 * is first encountered. If the tree gets deep enough or the 786 * number of symbolic links to directories is high enough, 787 * something faster might be worthwhile. 788 */ 789 for (t = p->fts_parent; 790 t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent) 791 if (ino == t->fts_ino && dev == t->fts_dev) { 792 p->fts_cycle = t; 793 return (FTS_DC); 794 } 795 return (FTS_D); 796 } 797 if (S_ISLNK(sbp->st_mode)) 798 return (FTS_SL); 799 if (S_ISREG(sbp->st_mode)) 800 return (FTS_F); 801 return (FTS_DEFAULT); 802 } 803 804 static FTSENT * 805 fts_sort(sp, head, nitems) 806 FTS *sp; 807 FTSENT *head; 808 register int nitems; 809 { 810 register FTSENT **ap, *p; 811 812 /* 813 * Construct an array of pointers to the structures and call qsort(3). 814 * Reassemble the array in the order returned by qsort. If unable to 815 * sort for memory reasons, return the directory entries in their 816 * current order. Allocate enough space for the current needs plus 817 * 40 so don't realloc one entry at a time. 818 */ 819 if (nitems > sp->fts_nitems) { 820 sp->fts_nitems = nitems + 40; 821 if ((sp->fts_array = realloc(sp->fts_array, 822 (size_t)(sp->fts_nitems * sizeof(FTSENT *)))) == NULL) { 823 sp->fts_nitems = 0; 824 return (head); 825 } 826 } 827 for (ap = sp->fts_array, p = head; p; p = p->fts_link) 828 *ap++ = p; 829 qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), sp->fts_compar); 830 for (head = *(ap = sp->fts_array); --nitems; ++ap) 831 ap[0]->fts_link = ap[1]; 832 ap[0]->fts_link = NULL; 833 return (head); 834 } 835 836 static FTSENT * 837 fts_alloc(sp, name, namelen) 838 FTS *sp; 839 char *name; 840 register int namelen; 841 { 842 register FTSENT *p; 843 size_t len; 844 845 /* 846 * The file name is a variable length array and no stat structure is 847 * necessary if the user has set the nostat bit. Allocate the FTSENT 848 * structure, the file name and the stat structure in one chunk, but 849 * be careful that the stat structure is reasonably aligned. Since the 850 * fts_name field is declared to be of size 1, the fts_name pointer is 851 * namelen + 2 before the first possible address of the stat structure. 852 */ 853 len = sizeof(FTSENT) + namelen; 854 if (!ISSET(FTS_NOSTAT)) 855 len += sizeof(struct stat) + ALIGNBYTES; 856 if ((p = malloc(len)) == NULL) 857 return (NULL); 858 859 /* Copy the name plus the trailing NULL. */ 860 bcopy(name, p->fts_name, namelen + 1); 861 862 if (!ISSET(FTS_NOSTAT)) 863 p->fts_statp = (struct stat *)ALIGN(p->fts_name + namelen + 2); 864 p->fts_namelen = namelen; 865 p->fts_path = sp->fts_path; 866 p->fts_errno = 0; 867 p->fts_flags = 0; 868 p->fts_instr = FTS_NOINSTR; 869 p->fts_number = 0; 870 p->fts_pointer = NULL; 871 return (p); 872 } 873 874 static void 875 fts_lfree(head) 876 register FTSENT *head; 877 { 878 register FTSENT *p; 879 880 /* Free a linked list of structures. */ 881 while (p = head) { 882 head = head->fts_link; 883 free(p); 884 } 885 } 886 887 /* 888 * Allow essentially unlimited paths; find, rm, ls should all work on any tree. 889 * Most systems will allow creation of paths much longer than MAXPATHLEN, even 890 * though the kernel won't resolve them. Add the size (not just what's needed) 891 * plus 256 bytes so don't realloc the path 2 bytes at a time. 892 */ 893 static int 894 fts_palloc(sp, more) 895 FTS *sp; 896 size_t more; 897 { 898 sp->fts_pathlen += more + 256; 899 sp->fts_path = realloc(sp->fts_path, (size_t)sp->fts_pathlen); 900 return (sp->fts_path == NULL); 901 } 902 903 /* 904 * When the path is realloc'd, have to fix all of the pointers in structures 905 * already returned. 906 */ 907 static void 908 fts_padjust(sp, addr) 909 FTS *sp; 910 void *addr; 911 { 912 FTSENT *p; 913 914 #define ADJUST(p) { \ 915 (p)->fts_accpath = addr + ((p)->fts_accpath - (p)->fts_path); \ 916 (p)->fts_path = addr; \ 917 } 918 /* Adjust the current set of children. */ 919 for (p = sp->fts_child; p; p = p->fts_link) 920 ADJUST(p); 921 922 /* Adjust the rest of the tree. */ 923 for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) { 924 ADJUST(p); 925 p = p->fts_link ? p->fts_link : p->fts_parent; 926 } 927 } 928 929 static size_t 930 fts_maxarglen(argv) 931 char * const *argv; 932 { 933 size_t len, max; 934 935 for (max = 0; *argv; ++argv) 936 if ((len = strlen(*argv)) > max) 937 max = len; 938 return (max); 939 } 940