1 /*	$Id: fts.c,v 1.5 2000/11/25 16:33:36 arnd Exp $	*/

     2 //

     3 // © Portions Copyright (c) Symbian Software Ltd 2007. All rights reserved.

     4 //

     5 /*-

     6  * Copyright (c) 1990, 1993, 1994

     7  *	The Regents of the University of California.  All rights reserved.

     8  *

     9  * Redistribution and use in source and binary forms, with or without

    10  * modification, are permitted provided that the following conditions

    11  * are met:

    12  * 1. Redistributions of source code must retain the above copyright

    13  *    notice, this list of conditions and the following disclaimer.

    14  * 2. Redistributions in binary form must reproduce the above copyright

    15  *    notice, this list of conditions and the following disclaimer in the

    16  *    documentation and/or other materials provided with the distribution.

    17  * 3. All advertising materials mentioning features or use of this software

    18  *    must display the following acknowledgement:

    19  *	This product includes software developed by the University of

    20  *	California, Berkeley and its contributors.

    21  * 4. Neither the name of the University nor the names of its contributors

    22  *    may be used to endorse or promote products derived from this software

    23  *    without specific prior written permission.

    24  *

    25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

    26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

    27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

    28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

    29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

    30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

    31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

    32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

    33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

    34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

    35  * SUCH DAMAGE.

    36  */

    37 

    38 #define __NO_FCHDIR /* Fix me! fchdir fn not yet implemented (AH) */

    39 

    40 #define _BSD_SOURCE

    41 #include <sys/param.h>

    42 #include <sys/stat.h>

    43 #include <dirent.h>

    44 #ifndef __SYMBIAN32__

    45 #include <sys/direntx.h>

    46 #endif

    47 #include <errno.h>

    48 #include <fcntl.h>

    49 #include "fts.h"

    50 #include <stdlib.h>

    51 #include <string.h>

    52 #include <unistd.h>

    53 

    54 static FTSENT	*fts_alloc(FTS *, char *, size_t);

    55 static FTSENT	*fts_build(FTS *, int);

    56 static void	 fts_lfree(FTSENT *);

    57 static void	 fts_load(FTS *, FTSENT *);

    58 static size_t	 fts_maxarglen(char * const *);

    59 static void	 fts_padjust(FTS *, FTSENT *);

    60 static int	 fts_palloc(FTS *, size_t);

    61 static FTSENT	*fts_sort(FTS *, FTSENT *, size_t);

    62 static u_short	 fts_stat(FTS *, FTSENT *, int);

    63 static int	 fts_safe_changedir(FTS *, FTSENT *, int);

    64 

    65 #define	ISDOT(a)	(a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))

    66 

    67 #define	CLR(opt)	(sp->fts_options &= ~(opt))

    68 #define	ISSET(opt)	(sp->fts_options & (opt))

    69 #define	SET(opt)	(sp->fts_options |= (opt))

    70 

    71 #ifndef __NO_FCHDIR

    72 #define	CHDIR(sp, path)	(!ISSET(FTS_NOCHDIR) && chdir(path))

    73 #define	FCHDIR(sp, fd)	(!ISSET(FTS_NOCHDIR) && fchdir(fd))

    74 #else

    75 #define	CHDIR(sp, path)	(0)

    76 #define	FCHDIR(sp, fd)	(0)

    77 #endif

    78 

    79 #ifdef __SYMBIAN32__

    80 #ifdef __WINSCW__

    81 #pragma warn_unusedarg off

    82 #endif//__WINSCW__

    83 #ifdef __ARMCC__

    84 // Turn off the 'extended constant initialiser used' warning

    85 #pragma diag_remark 1294

    86 #endif

    87 #endif//__SYMBIAN32__

    88 

    89 /* fts_build flags */

    90 #define	BCHILD		1		/* fts_children */

    91 #define	BNAMES		2		/* fts_children, names only */

    92 #define	BREAD		3		/* fts_read */

    93 

    94 static void

    95 fts_load(sp, p)

    96 	FTS *sp;

    97 	register FTSENT *p;

    98 {

    99 	register size_t len;

   100 	register char *cp;

   101 

   102 	/*

   103 	 * Load the stream structure for the next traversal.  Since we don't

   104 	 * actually enter the directory until after the preorder visit, set

   105 	 * the fts_accpath field specially so the chdir gets done to the right

   106 	 * place and the user can access the first node.  From fts_open it's

   107 	 * known that the path will fit.

   108 	 */

   109 	len = p->fts_pathlen = p->fts_namelen;

   110 	memmove(sp->fts_path, p->fts_name, len + 1);

   111 

   112 	if (!(cp = strrchr(p->fts_name, '\\')))

   113 		cp = strrchr(p->fts_name, '\\');

   114 	if (cp && (cp != p->fts_name || cp[1])) {

   115 		len = strlen(++cp);

   116 		memmove(p->fts_name, cp, len + 1);

   117 		p->fts_namelen = len;

   118 	}

   119 	p->fts_accpath = p->fts_path = sp->fts_path;

   120 	sp->fts_dev = p->fts_dev;

   121 }

   122 

   123 /*

   124  * Special case of "/" at the end of the path so that slashes aren't

   125  * appended which would cause paths to be written as "....//foo".

   126  */

   127 #define	NAPPEND(p)							\

   128 	(p->fts_path[p->fts_pathlen - 1] == '/'				\

   129 	    ? p->fts_pathlen - 1 : p->fts_pathlen)

   130 

   131 /*

   132  * This is the tricky part -- do not casually change *anything* in here.  The

   133  * idea is to build the linked list of entries that are used by fts_children

   134  * and fts_read.  There are lots of special cases.

   135  *

   136  * The real slowdown in walking the tree is the stat calls.  If FTS_NOSTAT is

   137  * set and it's a physical walk (so that symbolic links can't be directories),

   138  * we can do things quickly.  First, if it's a 4.4BSD file system, the type

   139  * of the file is in the directory entry.  Otherwise, we assume that the number

   140  * of subdirectories in a node is equal to the number of links to the parent.

   141  * The former skips all stat calls.  The latter skips stat calls in any leaf

   142  * directories and for any files after the subdirectories in the directory have

   143  * been found, cutting the stat calls by about 2/3.

   144  */

   145 static FTSENT *

   146 fts_build(sp, type)

   147 	register FTS *sp;

   148 	int type;

   149 {

   150 	register struct dirent *dp;

   151 	register FTSENT *p, *head;

   152 	register size_t nitems;

   153 	FTSENT *cur, *tail;

   154 	DIR *dirp;

   155 	void *oldaddr;

   156 	int cderrno, descend, level, nlinks, /* oflag, */ saved_errno,

   157 	    nostat = 0, doadjust;

   158 	size_t len, maxlen;

   159 	char *cp = NULL;

   160 

   161 	/* Set current node pointer. */

   162 	cur = sp->fts_cur;

   163 

   164 	/*

   165 	 * Open the directory for reading.  If this fails, we're done.

   166 	 * If being called from fts_read, set the fts_info field.

   167 	 */

   168 #ifdef FTS_WHITEOUT

   169 	if (ISSET(FTS_WHITEOUT))

   170 		oflag = DTF_NODUP|DTF_REWIND;

   171 	else

   172 		oflag = DTF_HIDEW|DTF_NODUP|DTF_REWIND;

   173 #else

   174 #define __opendir2(path, flag) opendir(path)

   175 #endif

   176 	if ((dirp = __opendir2(cur->fts_accpath, oflag)) == NULL) {

   177 		if (type == BREAD) {

   178 			cur->fts_info = FTS_DNR;

   179 			cur->fts_errno = errno;

   180 		}

   181 		return (NULL);

   182 	}

   183 

   184 	/*

   185 	 * Nlinks is the number of possible entries of type directory in the

   186 	 * directory if we're cheating on stat calls, 0 if we're not doing

   187 	 * any stat calls at all, -1 if we're doing stats on everything.

   188 	 */

   189 	if (type == BNAMES)

   190 		nlinks = 0;

   191 	else if (ISSET(FTS_NOSTAT) && ISSET(FTS_PHYSICAL)) {

   192 		nlinks = cur->fts_nlink - (ISSET(FTS_SEEDOT) ? 0 : 2);

   193 		nostat = 1;

   194 	} else {

   195 		nlinks = -1;

   196 		nostat = 0;

   197 	}

   198 

   199 #ifdef notdef

   200 	(void)printf("nlinks == %d (cur: %d)\n", nlinks, cur->fts_nlink);

   201 	(void)printf("NOSTAT %d PHYSICAL %d SEEDOT %d\n",

   202 	    ISSET(FTS_NOSTAT), ISSET(FTS_PHYSICAL), ISSET(FTS_SEEDOT));

   203 #endif

   204 	/*

   205 	 * If we're going to need to stat anything or we want to descend

   206 	 * and stay in the directory, chdir.  If this fails we keep going,

   207 	 * but set a flag so we don't chdir after the post-order visit.

   208 	 * We won't be able to stat anything, but we can still return the

   209 	 * names themselves.  Note, that since fts_read won't be able to

   210 	 * chdir into the directory, it will have to return different path

   211 	 * names than before, i.e. "a/b" instead of "b".  Since the node

   212 	 * has already been visited in pre-order, have to wait until the

   213 	 * post-order visit to return the error.  There is a special case

   214 	 * here, if there was nothing to stat then it's not an error to

   215 	 * not be able to stat.  This is all fairly nasty.  If a program

   216 	 * needed sorted entries or stat information, they had better be

   217 	 * checking FTS_NS on the returned nodes.

   218 	 */

   219 	cderrno = 0;

   220 	if (nlinks || type == BREAD) {

   221 		if (fts_safe_changedir(sp, cur, dirfd(dirp))) {

   222 			if (nlinks && type == BREAD)

   223 				cur->fts_errno = errno;

   224 			cur->fts_flags |= FTS_DONTCHDIR;

   225 			descend = 0;

   226 			cderrno = errno;

   227 			(void)closedir(dirp);

   228 			dirp = NULL;

   229 		} else

   230 			descend = 1;

   231 	} else

   232 		descend = 0;

   233 

   234 	/*

   235 	 * Figure out the max file name length that can be stored in the

   236 	 * current path -- the inner loop allocates more path as necessary.

   237 	 * We really wouldn't have to do the maxlen calculations here, we

   238 	 * could do them in fts_read before returning the path, but it's a

   239 	 * lot easier here since the length is part of the dirent structure.

   240 	 *

   241 	 * If not changing directories set a pointer so that can just append

   242 	 * each new name into the path.

   243 	 */

   244 	len = NAPPEND(cur);

   245 	if (ISSET(FTS_NOCHDIR)) {

   246 		cp = sp->fts_path + len;

   247 		*cp++ = '\\';

   248 	}

   249 	len++;

   250 	maxlen = sp->fts_pathlen - len;

   251 

   252 	level = cur->fts_level + 1;

   253 

   254 	/* Read the directory, attaching each entry to the `link' pointer. */

   255 	doadjust = 0;

   256 	for (head = tail = NULL, nitems = 0; dirp && (dp = readdir(dirp));) {

   257 		if (!ISSET(FTS_SEEDOT) && ISDOT(dp->d_name))

   258 			continue;

   259 

   260 		if ((p = fts_alloc(sp, dp->d_name, dp->d_namlen)) == NULL)

   261 			goto mem1;

   262 		if (dp->d_namlen >= maxlen) {	/* include space for NUL */

   263 			oldaddr = sp->fts_path;

   264 			if (fts_palloc(sp, dp->d_namlen +len + 1)) {

   265 				/*

   266 				 * No more memory for path or structures.  Save

   267 				 * errno, free up the current structure and the

   268 				 * structures already allocated.

   269 				 */

   270 mem1:				saved_errno = errno;

   271 				if (p)

   272 					free(p);

   273 				fts_lfree(head);

   274 				(void)closedir(dirp);

   275 				cur->fts_info = FTS_ERR;

   276 				SET(FTS_STOP);

   277 				errno = saved_errno;

   278 				return (NULL);

   279 			}

   280 			/* Did realloc() change the pointer? */

   281 			if (oldaddr != sp->fts_path) {

   282 				doadjust = 1;

   283 				if (ISSET(FTS_NOCHDIR))

   284 					cp = sp->fts_path + len;

   285 			}

   286 			maxlen = sp->fts_pathlen - len;

   287 		}

   288 

   289 		if (len + dp->d_namlen >= USHRT_MAX) {

   290 			/*

   291 			 * In an FTSENT, fts_pathlen is a u_short so it is

   292 			 * possible to wraparound here.  If we do, free up

   293 			 * the current structure and the structures already

   294 			 * allocated, then error out with ENAMETOOLONG.

   295 			 */

   296 			free(p);

   297 			fts_lfree(head);

   298 			(void)closedir(dirp);

   299 			cur->fts_info = FTS_ERR;

   300 			SET(FTS_STOP);

   301 			errno = ENAMETOOLONG;

   302 			return (NULL);

   303 		}

   304 		p->fts_level = level;

   305 		p->fts_parent = sp->fts_cur;

   306 		p->fts_pathlen = len + dp->d_namlen;

   307 

   308 #ifdef FTS_WHITEOUT

   309 		if (dp->d_type == DT_WHT)

   310 			p->fts_flags |= FTS_ISW;

   311 #endif

   312 

   313 		if (nlinks == 0 || (nostat &&

   314 		    dp->d_type != DT_DIR && dp->d_type != DT_UNKNOWN)

   315 		    ) {

   316 			p->fts_accpath =

   317 			    ISSET(FTS_NOCHDIR) ? p->fts_path : p->fts_name;

   318 			p->fts_info = FTS_NSOK;

   319 		} else {

   320 			/* Build a file name for fts_stat to stat. */

   321 			if (ISSET(FTS_NOCHDIR)) {

   322 				p->fts_accpath = p->fts_path;

   323 				memmove(cp, p->fts_name, p->fts_namelen + 1);

   324 			} else

   325 				p->fts_accpath = p->fts_name;

   326 			/* Stat it. */

   327 			p->fts_info = fts_stat(sp, p, 0);

   328 

   329 			/* Decrement link count if applicable. */

   330 			if (nlinks > 0 && (p->fts_info == FTS_D ||

   331 			    p->fts_info == FTS_DC || p->fts_info == FTS_DOT))

   332 				--nlinks;

   333 		}

   334 

   335 		/* We walk in directory order so "ls -f" doesn't get upset. */

   336 		p->fts_link = NULL;

   337 		if (head == NULL)

   338 			head = tail = p;

   339 		else {

   340 			tail->fts_link = p;

   341 			tail = p;

   342 		}

   343 		++nitems;

   344 	}

   345 	if (dirp)

   346 		(void)closedir(dirp);

   347 

   348 	/*

   349 	 * If realloc() changed the address of the path, adjust the

   350 	 * addresses for the rest of the tree and the dir list.

   351 	 */

   352 	if (doadjust)

   353 		fts_padjust(sp, head);

   354 

   355 	/*

   356 	 * If not changing directories, reset the path back to original

   357 	 * state.

   358 	 */

   359 	if (ISSET(FTS_NOCHDIR)) {

   360 		if (len == sp->fts_pathlen || nitems == 0)

   361 			--cp;

   362 		*cp = '\0';

   363 	}

   364 

   365 	/*

   366 	 * If descended after called from fts_children or after called from

   367 	 * fts_read and nothing found, get back.  At the root level we use

   368 	 * the saved fd; if one of fts_open()'s arguments is a relative path

   369 	 * to an empty directory, we wind up here with no other way back.  If

   370 	 * can't get back, we're done.

   371 	 */

   372 	if (descend && (type == BCHILD || !nitems) &&

   373 	    (cur->fts_level == FTS_ROOTLEVEL ?

   374 	    FCHDIR(sp, sp->fts_rfd) : CHDIR(sp, ".."))) {

   375 		cur->fts_info = FTS_ERR;

   376 		SET(FTS_STOP);

   377 		return (NULL);

   378 	}

   379 

   380 	/* If didn't find anything, return NULL. */

   381 	if (!nitems && (head == NULL)) {

   382 		if (type == BREAD)

   383 			cur->fts_info = FTS_DP;

   384 		return (NULL);

   385 	}

   386 

   387 	/* Sort the entries. */

   388 	if (sp->fts_compar && nitems > 1)

   389 		head = fts_sort(sp, head, nitems);

   390 	return (head);

   391 }

   392 

   393 static u_short

   394 fts_stat(sp, p, follow)

   395 	FTS *sp;

   396 	register FTSENT *p;

   397 	int follow;

   398 {

   399 

   400 	register dev_t dev;

   401 	register ino_t ino;

   402 	struct stat *sbp, sb;

   403 	int saved_errno;

   404 

   405 	/* If user needs stat info, stat buffer already allocated. */

   406 	sbp = ISSET(FTS_NOSTAT) ? &sb : p->fts_statp;

   407 

   408 #ifdef FTS_WHITEOUT

   409 	/* check for whiteout */

   410 	if (p->fts_flags & FTS_ISW) {

   411 		if (sbp != &sb) {

   412 			memset(sbp, '\0', sizeof (*sbp));

   413 			sbp->st_mode = S_IFWHT;

   414 		}

   415 		return (FTS_W);

   416 	}

   417 #endif

   418 

   419 	/*

   420 	 * If doing a logical walk, or application requested FTS_FOLLOW, do

   421 	 * a stat(2).  If that fails, check for a non-existent symlink.  If

   422 	 * fail, set the errno from the stat call.

   423 	 */

   424 	if (ISSET(FTS_LOGICAL) || follow) {

   425 		if (stat(p->fts_accpath, sbp)) {

   426 			saved_errno = errno;

   427 			if (!lstat(p->fts_accpath, sbp)) {

   428 				errno = 0;

   429 				return (FTS_SLNONE);

   430 			}

   431 			p->fts_errno = saved_errno;

   432 			goto err;

   433 		}

   434 	} else if (lstat(p->fts_accpath, sbp)) {

   435 		p->fts_errno = errno;

   436 err:		memset(sbp, 0, sizeof(struct stat));

   437 		return (FTS_NS);

   438 	}

   439 

   440 	if (S_ISDIR(sbp->st_mode)) {

   441 		/*

   442 		 * Set the device/inode.  Used to find cycles and check for

   443 		 * crossing mount points.  Also remember the link count, used

   444 		 * in fts_build to limit the number of stat calls.  It is

   445 		 * understood that these fields are only referenced if fts_info

   446 		 * is set to FTS_D.

   447 		 */

   448 		dev = p->fts_dev = sbp->st_dev;

   449 		ino = p->fts_ino = sbp->st_ino;

   450 		p->fts_nlink = sbp->st_nlink;

   451 

   452 		if (ISDOT(p->fts_name))

   453 			return (FTS_DOT);

   454 

   455 		/*

   456 		 * Cycle detection is done by brute force when the directory

   457 		 * is first encountered.  If the tree gets deep enough or the

   458 		 * number of symbolic links to directories is high enough,

   459 		 * something faster might be worthwhile.

   460 		 */

   461 #ifndef __SYMBIAN32__		 

   462 		//fts_ino is set

   463 		for (t = p->fts_parent;

   464 		    t->fts_level >= FTS_ROOTLEVEL; t = t->fts_parent)

   465 			if (ino == t->fts_ino && dev == t->fts_dev) {

   466 				p->fts_cycle = t;

   467 				return (FTS_DC);

   468 			}

   469 #endif

   470 		return (FTS_D);

   471 	}

   472 	if (S_ISLNK(sbp->st_mode))

   473 		return (FTS_SL);

   474 	if (S_ISREG(sbp->st_mode))

   475 		return (FTS_F);

   476 	return (FTS_DEFAULT);

   477 }

   478 

   479 typedef int (*qsType)(const void *, const void *);

   480 

   481 static FTSENT *

   482 fts_sort(sp, head, nitems)

   483 	FTS *sp;

   484 	FTSENT *head;

   485 	register size_t nitems;

   486 {

   487 	register FTSENT **ap, *p;

   488 

   489 	/*

   490 	 * Construct an array of pointers to the structures and call qsort(3).

   491 	 * Reassemble the array in the order returned by qsort.  If unable to

   492 	 * sort for memory reasons, return the directory entries in their

   493 	 * current order.  Allocate enough space for the current needs plus

   494 	 * 40 so don't realloc one entry at a time.

   495 	 */

   496 	if (nitems > sp->fts_nitems) {

   497 		struct _ftsent **a;

   498 

   499 		sp->fts_nitems = nitems + 40;

   500 		if ((a = realloc(sp->fts_array,

   501 		    sp->fts_nitems * sizeof(FTSENT *))) == NULL) {

   502 			if (sp->fts_array)

   503 				free(sp->fts_array);

   504 			sp->fts_array = NULL;

   505 			sp->fts_nitems = 0;

   506 			return (head);

   507 		}

   508 		sp->fts_array = a;

   509 	}

   510 	for (ap = sp->fts_array, p = head; p; p = p->fts_link)

   511 		*ap++ = p;

   512 	qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), 

   513 		(qsType)sp->fts_compar);

   514 	for (head = *(ap = sp->fts_array); --nitems; ++ap)

   515 		ap[0]->fts_link = ap[1];

   516 	ap[0]->fts_link = NULL;

   517 	return (head);

   518 }

   519 

   520 static FTSENT *

   521 fts_alloc(sp, name, namelen)

   522 	FTS *sp;

   523 	char *name;

   524 	register size_t namelen;

   525 {

   526 	register FTSENT *p;

   527 	size_t len;

   528 

   529 	/*

   530 	 * The file name is a variable length array and no stat structure is

   531 	 * necessary if the user has set the nostat bit.  Allocate the FTSENT

   532 	 * structure, the file name and the stat structure in one chunk, but

   533 	 * be careful that the stat structure is reasonably aligned.  Since the

   534 	 * fts_name field is declared to be of size 1, the fts_name pointer is

   535 	 * namelen + 2 before the first possible address of the stat structure.

   536 	 */

   537 	len = sizeof(FTSENT) + namelen;

   538 	if (!ISSET(FTS_NOSTAT))

   539 		len += sizeof(struct stat) + ALIGNBYTES;

   540 	if ((p = malloc(len)) == NULL)

   541 		return (NULL);

   542 

   543 	/* Copy the name and guarantee NUL termination. */

   544 	memmove(p->fts_name, name, namelen);

   545 	p->fts_name[namelen] = '\0';

   546 

   547 	if (!ISSET(FTS_NOSTAT))

   548 		p->fts_statp = (struct stat *)ALIGN(p->fts_name + namelen + 2);

   549 	p->fts_namelen = namelen;

   550 	p->fts_path = sp->fts_path;

   551 	p->fts_errno = 0;

   552 	p->fts_flags = 0;

   553 	p->fts_instr = FTS_NOINSTR;

   554 	p->fts_number = 0;

   555 	p->fts_pointer = NULL;

   556 	return (p);

   557 }

   558 

   559 static void

   560 fts_lfree(head)

   561 	register FTSENT *head;

   562 {

   563 	register FTSENT *p;

   564 

   565 	/* Free a linked list of structures. */

   566 	while ((p = head)) {

   567 		head = head->fts_link;

   568 		free(p);

   569 	}

   570 }

   571 

   572 /*

   573  * Allow essentially unlimited paths; find, rm, ls should all work on any tree.

   574  * Most systems will allow creation of paths much longer than MAXPATHLEN, even

   575  * though the kernel won't resolve them.  Add the size (not just what's needed)

   576  * plus 256 bytes so don't realloc the path 2 bytes at a time.

   577  */

   578 static int

   579 fts_palloc(sp, more)

   580 	FTS *sp;

   581 	size_t more;

   582 {

   583 	char *p;

   584 

   585 	sp->fts_pathlen += more + 256;

   586 	/*

   587 	 * Check for possible wraparound.  In an FTS, fts_pathlen is

   588 	 * a signed int but in an FTSENT it is an unsigned short.

   589 	 * We limit fts_pathlen to USHRT_MAX to be safe in both cases.

   590 	 */

   591 	if (/* sp->fts_pathlen < 0 || */ sp->fts_pathlen >= USHRT_MAX) {

   592 		if (sp->fts_path)

   593 			free(sp->fts_path);

   594 		sp->fts_path = NULL;

   595 		errno = ENAMETOOLONG;

   596 		return (1);

   597 	}

   598 	p = realloc(sp->fts_path, sp->fts_pathlen);

   599 	if (p == NULL) {

   600 		if (sp->fts_path)

   601 			free(sp->fts_path);

   602 		sp->fts_path = NULL;

   603 		return (1);

   604 	}

   605 	sp->fts_path = p;

   606 	return (0);

   607 }

   608 

   609 /*

   610  * When the path is realloc'd, have to fix all of the pointers in structures

   611  * already returned.

   612  */

   613 static void

   614 fts_padjust(sp, head)

   615 	FTS *sp;

   616 	FTSENT *head;

   617 {

   618 	FTSENT *p;

   619 	char *addr = sp->fts_path;

   620 

   621 #define	ADJUST(p) {							\

   622 	if ((p)->fts_accpath != (p)->fts_name) {			\

   623 		(p)->fts_accpath =					\

   624 		    (char *)addr + ((p)->fts_accpath - (p)->fts_path);	\

   625 	}								\

   626 	(p)->fts_path = addr;						\

   627 }

   628 	/* Adjust the current set of children. */

   629 	for (p = sp->fts_child; p; p = p->fts_link)

   630 		ADJUST(p);

   631 

   632 	/* Adjust the rest of the tree, including the current level. */

   633 	for (p = head; p->fts_level >= FTS_ROOTLEVEL;) {

   634 		ADJUST(p);

   635 		p = p->fts_link ? p->fts_link : p->fts_parent;

   636 	}

   637 }

   638 

   639 static size_t

   640 fts_maxarglen(argv)

   641 	char * const *argv;

   642 {

   643 	size_t len, max;

   644 

   645 	for (max = 0; *argv; ++argv)

   646 		if ((len = strlen(*argv)) > max)

   647 			max = len;

   648 	return (max + 1);

   649 }

   650 

   651 /*

   652  * Change to dir specified by fd or p->fts_accpath without getting

   653  * tricked by someone changing the world out from underneath us.

   654  * Assumes p->fts_dev and p->fts_ino are filled in.

   655  */

   656 static int

   657 fts_safe_changedir(sp, p, fd)

   658 	FTS *sp;

   659 	FTSENT *p;

   660 	int fd;

   661 {

   662 #ifndef __NO_FCHDIR

   663 	int ret, oerrno, newfd;

   664 	struct stat sb;

   665 

   666 	newfd = fd;

   667 	if (ISSET(FTS_NOCHDIR))

   668 		return (0);

   669 	if (fd < 0 && (newfd = open(p->fts_accpath, O_RDONLY, 0)) < 0)

   670 		return (-1);

   671 	if (fstat(newfd, &sb)) {

   672 		ret = -1;

   673 		goto bail;

   674 	}

   675 	if (p->fts_dev != sb.st_dev || p->fts_ino != sb.st_ino) {

   676 		errno = ENOENT;		/* disinformation */

   677 		ret = -1;

   678 		goto bail;

   679 	}

   680 	ret = fchdir(newfd);

   681 bail:

   682 	oerrno = errno;

   683 	if (fd < 0)

   684 		(void)close(newfd);

   685 	errno = oerrno;

   686 	return (ret);

   687 #else

   688 	return (0);

   689 #endif

   690 }

   691 

   692 

   693 FTS *

   694 fts_open(argv, options, compar)

   695 	char * const *argv;

   696 	register int options;

   697 	int (*compar)(const FTSENT **, const FTSENT **);

   698 {

   699 	register FTS *sp;

   700 	register FTSENT *p, *root;

   701 	register size_t nitems;

   702 	FTSENT *parent, *tmp = NULL;

   703 	size_t len;

   704 

   705 	/* Options check. */

   706 	if (options & ~FTS_OPTIONMASK) {

   707 		errno = EINVAL;

   708 		return (NULL);

   709 	}

   710 

   711 	/* Allocate/initialize the stream */

   712 	if ((sp = malloc((u_int)sizeof(FTS))) == NULL)

   713 		return (NULL);

   714 	memset(sp, 0, sizeof(FTS));

   715 	sp->fts_compar = compar;

   716 #ifndef __NO_FCHDIR 

   717 	sp->fts_options = options;

   718 

   719 	/* Logical walks turn on NOCHDIR; symbolic links are too hard. */

   720 	if (ISSET(FTS_LOGICAL))

   721 		SET(FTS_NOCHDIR);

   722 #else

   723 	sp->fts_options = options | FTS_NOCHDIR;

   724 #endif

   725 	/*

   726 	 * Start out with 1K of path space, and enough, in any case,

   727 	 * to hold the user's paths.

   728 	 */

   729 	if (fts_palloc(sp, MAX(fts_maxarglen(argv), MAXPATHLEN)))

   730 		goto mem1;

   731 

   732 	/* Allocate/initialize root's parent. */

   733 	if ((parent = fts_alloc(sp, "", 0)) == NULL)

   734 		goto mem2;

   735 	parent->fts_level = FTS_ROOTPARENTLEVEL;

   736 

   737 	/* Allocate/initialize root(s). */

   738 	for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) {

   739 		/* Don't allow zero-length paths. */

   740 		if ((len = strlen(*argv)) == 0) {

   741 			errno = ENOENT;

   742 			goto mem3;

   743 		}

   744 

   745 		p = fts_alloc(sp, *argv, len);

   746 		p->fts_level = FTS_ROOTLEVEL;

   747 		p->fts_parent = parent;

   748 		p->fts_accpath = p->fts_name;

   749 		p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW));

   750 

   751 		/* Command-line "." and ".." are real directories. */

   752 		if (p->fts_info == FTS_DOT)

   753 			p->fts_info = FTS_D;

   754 

   755 		/*

   756 		 * If comparison routine supplied, traverse in sorted

   757 		 * order; otherwise traverse in the order specified.

   758 		 */

   759 		if (compar) {

   760 			p->fts_link = root;

   761 			root = p;

   762 		} else {

   763 			p->fts_link = NULL;

   764 			if (root == NULL)

   765 				tmp = root = p;

   766 			else {

   767 				tmp->fts_link = p;

   768 				tmp = p;

   769 			}

   770 		}

   771 	}

   772 	if (compar && nitems > 1)

   773 		root = fts_sort(sp, root, nitems);

   774 

   775 	/*

   776 	 * Allocate a dummy pointer and make fts_read think that we've just

   777 	 * finished the node before the root(s); set p->fts_info to FTS_INIT

   778 	 * so that everything about the "current" node is ignored.

   779 	 */

   780 	if ((sp->fts_cur = fts_alloc(sp, "", 0)) == NULL)

   781 		goto mem3;

   782 	sp->fts_cur->fts_link = root;

   783 	sp->fts_cur->fts_info = FTS_INIT;

   784 

   785 #ifndef __NO_FCHDIR 

   786 	/*

   787 	 * If using chdir(2), grab a file descriptor pointing to dot to ensure

   788 	 * that we can get back here; this could be avoided for some paths,

   789 	 * but almost certainly not worth the effort.  Slashes, symbolic links,

   790 	 * and ".." are all fairly nasty problems.  Note, if we can't get the

   791 	 * descriptor we run anyway, just more slowly.

   792 	 */

   793 	if (!ISSET(FTS_NOCHDIR) && (sp->fts_rfd = open(".", O_RDONLY, 0)) < 0)

   794 		SET(FTS_NOCHDIR);

   795 #endif

   796 

   797 	return (sp);

   798 

   799 mem3:	fts_lfree(root);

   800 	free(parent);

   801 mem2:	free(sp->fts_path);

   802 mem1:	free(sp);

   803 	return (NULL);

   804 }

   805 

   806 

   807 int

   808 fts_close(sp)

   809 	FTS *sp;

   810 {

   811 	register FTSENT *freep, *p;

   812 	/* int saved_errno = 0; */

   813 

   814 	/*

   815 	 * This still works if we haven't read anything -- the dummy structure

   816 	 * points to the root list, so we step through to the end of the root

   817 	 * list which has a valid parent pointer.

   818 	 */

   819 	if (sp->fts_cur) {

   820 		for (p = sp->fts_cur; p->fts_level >= FTS_ROOTLEVEL;) {

   821 			freep = p;

   822 			p = p->fts_link ? p->fts_link : p->fts_parent;

   823 			free(freep);

   824 		}

   825 		free(p);

   826 	}

   827 

   828 	/* Free up child linked list, sort array, path buffer. */

   829 	if (sp->fts_child)

   830 		fts_lfree(sp->fts_child);

   831 	if (sp->fts_array)

   832 		free(sp->fts_array);

   833 	free(sp->fts_path);

   834 

   835 #ifndef __NO_FCHDIR 

   836 	/* Return to original directory, save errno if necessary. */

   837 	if (!ISSET(FTS_NOCHDIR)) {

   838 		saved_errno = fchdir(sp->fts_rfd) ? errno : 0;

   839 		(void)close(sp->fts_rfd);

   840 	}

   841 	/* Set errno and return. */

   842 	if (!ISSET(FTS_NOCHDIR) && saved_errno) {

   843 		/* Free up the stream pointer. */

   844 		free(sp);

   845 		errno = saved_errno;

   846 		return (-1);

   847 	}

   848 #endif

   849 

   850 	/* Free up the stream pointer. */

   851 	free(sp);

   852 	return (0);

   853 }

   854 

   855 FTSENT *

   856 fts_read(sp)

   857 	register FTS *sp;

   858 {

   859 	register FTSENT *p, *tmp;

   860 	register int instr;

   861 	register char *t;

   862 	/* int saved_errno; */

   863 

   864 	/* If finished or unrecoverable error, return NULL. */

   865 	if (sp->fts_cur == NULL || ISSET(FTS_STOP))

   866 		return (NULL);

   867 

   868 	/* Set current node pointer. */

   869 	p = sp->fts_cur;

   870 

   871 	/* Save and zero out user instructions. */

   872 	instr = p->fts_instr;

   873 	p->fts_instr = FTS_NOINSTR;

   874 

   875 	/* Any type of file may be re-visited; re-stat and re-turn. */

   876 	if (instr == FTS_AGAIN) {

   877 		p->fts_info = fts_stat(sp, p, 0);

   878 		return (p);

   879 	}

   880 

   881 	/*

   882 	 * Following a symlink -- SLNONE test allows application to see

   883 	 * SLNONE and recover.  If indirecting through a symlink, have

   884 	 * keep a pointer to current location.  If unable to get that

   885 	 * pointer, follow fails.

   886 	 */

   887 	if (instr == FTS_FOLLOW &&

   888 	    (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {

   889 		p->fts_info = fts_stat(sp, p, 1);

   890 		if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {

   891 			if ((p->fts_symfd = open(".", O_RDONLY, 0)) < 0) {

   892 				p->fts_errno = errno;

   893 				p->fts_info = FTS_ERR;

   894 			} else

   895 				p->fts_flags |= FTS_SYMFOLLOW;

   896 		}

   897 		return (p);

   898 	}

   899 

   900 	/* Directory in pre-order. */

   901 	if (p->fts_info == FTS_D) {

   902 		/* If skipped or crossed mount point, do post-order visit. */

   903 		if (instr == FTS_SKIP ||

   904 		    (ISSET(FTS_XDEV) && p->fts_dev != sp->fts_dev)) {

   905 			if (p->fts_flags & FTS_SYMFOLLOW)

   906 				(void)close(p->fts_symfd);

   907 			if (sp->fts_child) {

   908 				fts_lfree(sp->fts_child);

   909 				sp->fts_child = NULL;

   910 			}

   911 			p->fts_info = FTS_DP;

   912 			return (p);

   913 		}

   914 

   915 		/* Rebuild if only read the names and now traversing. */

   916 		if (sp->fts_child && ISSET(FTS_NAMEONLY)) {

   917 			CLR(FTS_NAMEONLY);

   918 			fts_lfree(sp->fts_child);

   919 			sp->fts_child = NULL;

   920 		}

   921 

   922 		/*

   923 		 * Cd to the subdirectory.

   924 		 *

   925 		 * If have already read and now fail to chdir, whack the list

   926 		 * to make the names come out right, and set the parent errno

   927 		 * so the application will eventually get an error condition.

   928 		 * Set the FTS_DONTCHDIR flag so that when we logically change

   929 		 * directories back to the parent we don't do a chdir.

   930 		 *

   931 		 * If haven't read do so.  If the read fails, fts_build sets

   932 		 * FTS_STOP or the fts_info field of the node.

   933 		 */

   934 		if (sp->fts_child) {

   935 			if (fts_safe_changedir(sp, p, -1)) {

   936 				p->fts_errno = errno;

   937 				p->fts_flags |= FTS_DONTCHDIR;

   938 				for (p = sp->fts_child; p; p = p->fts_link)

   939 					p->fts_accpath =

   940 					    p->fts_parent->fts_accpath;

   941 			}

   942 		} else if ((sp->fts_child = fts_build(sp, BREAD)) == NULL) {

   943 			if (ISSET(FTS_STOP))

   944 				return (NULL);

   945 			return (p);

   946 		}

   947 		p = sp->fts_child;

   948 		sp->fts_child = NULL;

   949 		goto name;

   950 	}

   951 

   952 	/* Move to the next node on this level. */

   953 next:	tmp = p;

   954 	if ((p = p->fts_link)) {

   955 		free(tmp);

   956 

   957 		/*

   958 		 * If reached the top, return to the original directory (or

   959 		 * the root of the tree), and load the paths for the next root.

   960 		 */

   961 		if (p->fts_level == FTS_ROOTLEVEL) {

   962 			if ((sp->fts_options & FTS_CHDIRROOT)) {

   963 				if (chdir(p->fts_accpath)) {

   964 					SET(FTS_STOP);

   965 					return (NULL);

   966 				}

   967 			} else {

   968 				if (FCHDIR(sp, sp->fts_rfd)) {

   969 					SET(FTS_STOP);

   970 					return (NULL);

   971 				}

   972 			}

   973 			fts_load(sp, p);

   974 			return (sp->fts_cur = p);

   975 		}

   976 

   977 		/*

   978 		 * User may have called fts_set on the node.  If skipped,

   979 		 * ignore.  If followed, get a file descriptor so we can

   980 		 * get back if necessary.

   981 		 */

   982 		if (p->fts_instr == FTS_SKIP)

   983 			goto next;

   984 		if (p->fts_instr == FTS_FOLLOW) {

   985 			p->fts_info = fts_stat(sp, p, 1);

   986 			if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {

   987 				if ((p->fts_symfd =

   988 				    open(".", O_RDONLY, 0)) < 0) {

   989 					p->fts_errno = errno;

   990 					p->fts_info = FTS_ERR;

   991 				} else

   992 					p->fts_flags |= FTS_SYMFOLLOW;

   993 			}

   994 			p->fts_instr = FTS_NOINSTR;

   995 		}

   996 

   997 name:		t = sp->fts_path + NAPPEND(p->fts_parent);

   998 		*t++ = '\\';

   999 		memmove(t, p->fts_name, p->fts_namelen + 1);

  1000 		return (sp->fts_cur = p);

  1001 	}

  1002 

  1003 	/* Move up to the parent node. */

  1004 	p = tmp->fts_parent;

  1005 	free(tmp);

  1006 

  1007 	if (p->fts_level == FTS_ROOTPARENTLEVEL) {

  1008 		/*

  1009 		 * Done; free everything up and set errno to 0 so the user

  1010 		 * can distinguish between error and EOF.

  1011 		 */

  1012 		free(p);

  1013 		errno = 0;

  1014 		return (sp->fts_cur = NULL);

  1015 	}

  1016 

  1017 	/* NUL terminate the pathname. */

  1018 	sp->fts_path[p->fts_pathlen] = '\0';

  1019 

  1020 	/*

  1021 	 * Return to the parent directory.  If at a root node or came through

  1022 	 * a symlink, go back through the file descriptor.  Otherwise, cd up

  1023 	 * one directory.

  1024 	 */

  1025 	if (p->fts_level == FTS_ROOTLEVEL) {

  1026 		if ((sp->fts_options & FTS_CHDIRROOT)) {

  1027 			if (chdir(p->fts_accpath)) {

  1028 				SET(FTS_STOP);

  1029 				return (NULL);

  1030 			}

  1031 		} else {

  1032 			if (FCHDIR(sp, sp->fts_rfd)) {

  1033 				SET(FTS_STOP);

  1034 				return (NULL);

  1035 			}

  1036 		}

  1037 	} else if (p->fts_flags & FTS_SYMFOLLOW) {

  1038 #ifndef __NO_FCHDIR 

  1039 		if (FCHDIR(sp, p->fts_symfd)) {

  1040 			saved_errno = errno;

  1041 			(void)close(p->fts_symfd);

  1042 			errno = saved_errno;

  1043 			SET(FTS_STOP);

  1044 			return (NULL);

  1045 		}

  1046 #endif

  1047 		(void)close(p->fts_symfd);

  1048 	} else if (!(p->fts_flags & FTS_DONTCHDIR)) {

  1049 		if (CHDIR(sp, "..")) {

  1050 			SET(FTS_STOP);

  1051 			return (NULL);

  1052 		}

  1053 	}

  1054 	p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;

  1055 	return (sp->fts_cur = p);

  1056 }

  1057 

  1058 /*

  1059  * Fts_set takes the stream as an argument although it's not used in this

  1060  * implementation; it would be necessary if anyone wanted to add global

  1061  * semantics to fts using fts_set.  An error return is allowed for similar

  1062  * reasons.

  1063  */

  1064 /* ARGSUSED */

  1065 int

  1066 fts_set(FTS *sp_dummy, FTSENT *p, int instr)

  1067 {

  1068 	if (instr && instr != FTS_AGAIN && instr != FTS_FOLLOW &&

  1069 	    instr != FTS_NOINSTR && instr != FTS_SKIP) {

  1070 		errno = EINVAL;

  1071 		return (1);

  1072 	}

  1073 	p->fts_instr = instr;

  1074 	return (0);

  1075 }

  1076 

  1077 FTSENT *

  1078 fts_children(sp, instr)

  1079 	register FTS *sp;

  1080 	int instr;

  1081 {

  1082 	register FTSENT *p;

  1083 /*	int fd; */

  1084 

  1085 	if (instr && instr != FTS_NAMEONLY) {

  1086 		errno = EINVAL;

  1087 		return (NULL);

  1088 	}

  1089 

  1090 	/* Set current node pointer. */

  1091 	p = sp->fts_cur;

  1092 

  1093 	/*

  1094 	 * Errno set to 0 so user can distinguish empty directory from

  1095 	 * an error.

  1096 	 */

  1097 	errno = 0;

  1098 

  1099 	/* Fatal errors stop here. */

  1100 	if (ISSET(FTS_STOP))

  1101 		return (NULL);

  1102 

  1103 	/* Return logical hierarchy of user's arguments. */

  1104 	if (p->fts_info == FTS_INIT)

  1105 		return (p->fts_link);

  1106 

  1107 	/*

  1108 	 * If not a directory being visited in pre-order, stop here.  Could

  1109 	 * allow FTS_DNR, assuming the user has fixed the problem, but the

  1110 	 * same effect is available with FTS_AGAIN.

  1111 	 */

  1112 	if (p->fts_info != FTS_D /* && p->fts_info != FTS_DNR */)

  1113 		return (NULL);

  1114 

  1115 	/* Free up any previous child list. */

  1116 	if (sp->fts_child)

  1117 		fts_lfree(sp->fts_child);

  1118 

  1119 	if (instr == FTS_NAMEONLY) {

  1120 		SET(FTS_NAMEONLY);

  1121 		instr = BNAMES;

  1122 	} else

  1123 		instr = BCHILD;

  1124 

  1125 #ifndef __NO_FCHDIR 

  1126 	/*

  1127 	 * If using chdir on a relative path and called BEFORE fts_read does

  1128 	 * its chdir to the root of a traversal, we can lose -- we need to

  1129 	 * chdir into the subdirectory, and we don't know where the current

  1130 	 * directory is, so we can't get back so that the upcoming chdir by

  1131 	 * fts_read will work.

  1132 	 */

  1133 	if (p->fts_level != FTS_ROOTLEVEL || p->fts_accpath[0] == '\\' ||

  1134 	    p->fts_accpath[0] == '\\' || ISSET(FTS_NOCHDIR))