1 /* $FreeBSD: src/sys/msdosfs/msdosfs_lookup.c,v 1.30.2.1 2000/11/03 15:55:39 bp Exp $ */
2 /* $DragonFly: src/sys/vfs/msdosfs/msdosfs_lookup.c,v 1.12 2004/10/12 19:21:00 dillon Exp $ */
3 /* $NetBSD: msdosfs_lookup.c,v 1.37 1997/11/17 15:36:54 ws Exp $ */
6 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
7 * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
9 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by TooLs GmbH.
22 * 4. The name of TooLs GmbH may not be used to endorse or promote products
23 * derived from this software without specific prior written permission.
25 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
29 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
30 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
31 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
32 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
33 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
34 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37 * Written by Paul Popelka (paulp@uts.amdahl.com)
39 * You can do anything you want with this software, just don't say you wrote
40 * it, and don't remove this notice.
42 * This software is provided "as is".
44 * The author supplies this software to be publicly redistributed on the
45 * understanding that the author is not responsible for the correct
46 * functioning of this software in any circumstances and is not liable for
47 * any damages caused by this software.
52 #include <sys/param.h>
53 #include <sys/systm.h>
55 #include <sys/vnode.h>
57 #include <sys/namei.h>
58 #include <sys/mount.h>
63 #include "msdosfsmount.h"
67 * When we search a directory the blocks containing directory entries are
68 * read and examined. The directory entries contain information that would
69 * normally be in the inode of a unix filesystem. This means that some of
70 * a directory's contents may also be in memory resident denodes (sort of
71 * an inode). This can cause problems if we are searching while some other
72 * process is modifying a directory. To prevent one process from accessing
73 * incompletely modified directory information we depend upon being the
74 * sole owner of a directory block. bread/brelse provide this service.
75 * This being the case, when a process modifies a directory it must first
76 * acquire the disk block that contains the directory entry to be modified.
77 * Then update the disk block and the denode, and then write the disk block
78 * out to disk. This way disk blocks containing directory entries and in
79 * memory denode's will be in synch.
81 * msdosfs_lookup(struct vnode *a_dvp, struct vnode **a_vpp,
82 * struct componentname *a_cnp)
85 msdosfs_lookup(struct vop_cachedlookup_args *ap)
87 struct vnode *vdp = ap->a_dvp;
88 struct vnode **vpp = ap->a_vpp;
89 struct componentname *cnp = ap->a_cnp;
101 int isadir; /* ~0 if found direntry is a directory */
102 u_long scn; /* starting cluster number */
106 struct msdosfsmount *pmp;
108 struct direntry *dep = NULL;
109 u_char dosfilename[12];
110 int flags = cnp->cn_flags;
111 int nameiop = cnp->cn_nameiop;
112 struct thread *td = cnp->cn_td;
118 cnp->cn_flags &= ~CNP_PDIRUNLOCK;
121 printf("msdosfs_lookup(): looking for %s\n", cnp->cn_nameptr);
126 lockparent = flags & CNP_LOCKPARENT;
127 wantparent = flags & (CNP_LOCKPARENT | CNP_WANTPARENT);
129 printf("msdosfs_lookup(): vdp %p, dp %p, Attr %02x\n",
130 vdp, dp, dp->de_Attributes);
134 * If they are going after the . or .. entry in the root directory,
135 * they won't find it. DOS filesystems don't have them in the root
136 * directory. So, we fake it. deget() is in on this scam too.
138 if ((vdp->v_flag & VROOT) && cnp->cn_nameptr[0] == '.' &&
139 (cnp->cn_namelen == 1 ||
140 (cnp->cn_namelen == 2 && cnp->cn_nameptr[1] == '.'))) {
141 isadir = ATTR_DIRECTORY;
144 printf("msdosfs_lookup(): looking for . or .. in root directory\n");
146 cluster = MSDOSFSROOT;
147 blkoff = MSDOSFSROOT_OFS;
151 switch (unix2dosfn((const u_char *)cnp->cn_nameptr, dosfilename,
153 pmp->pm_flags & MSDOSFSMNT_U2WTABLE, pmp->pm_u2d,
154 pmp->pm_flags & MSDOSFSMNT_ULTABLE, pmp->pm_lu)) {
160 wincnt = winSlotCnt((const u_char *)cnp->cn_nameptr,
161 cnp->cn_namelen) + 1;
165 wincnt = winSlotCnt((const u_char *)cnp->cn_nameptr,
166 cnp->cn_namelen) + 1;
169 if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME) {
173 unlen = winLenFixup(cnp->cn_nameptr, cnp->cn_namelen);
176 * Suppress search for slots unless creating
177 * file and at end of pathname, in which case
178 * we watch for a place to put the new file in
179 * case it doesn't already exist.
182 if ((nameiop == NAMEI_CREATE || nameiop == NAMEI_RENAME) &&
183 (flags & CNP_ISLASTCN))
187 printf("msdosfs_lookup(): dos version of filename %s, length %ld\n",
188 dosfilename, cnp->cn_namelen);
191 * Search the directory pointed at by vdp for the name pointed at
192 * by cnp->cn_nameptr.
196 * The outer loop ranges over the clusters that make up the
197 * directory. Note that the root directory is different from all
198 * other directories. It has a fixed number of blocks that are not
199 * part of the pool of allocatable clusters. So, we treat it a
200 * little differently. The root directory starts at "cluster" 0.
203 for (frcn = 0;; frcn++) {
204 error = pcbmap(dp, frcn, &bn, &cluster, &blsize);
210 error = bread(pmp->pm_devvp, bn, blsize, &bp);
215 for (blkoff = 0; blkoff < blsize;
216 blkoff += sizeof(struct direntry),
217 diroff += sizeof(struct direntry)) {
218 dep = (struct direntry *)(bp->b_data + blkoff);
220 * If the slot is empty and we are still looking
221 * for an empty then remember this one. If the
222 * slot is not empty then check to see if it
223 * matches what we are looking for. If the slot
224 * has never been filled with anything, then the
225 * remainder of the directory has never been used,
226 * so there is no point in searching it.
228 if (dep->deName[0] == SLOT_EMPTY ||
229 dep->deName[0] == SLOT_DELETED) {
231 * Drop memory of previous long matches
235 if (slotcount < wincnt) {
239 if (dep->deName[0] == SLOT_EMPTY) {
245 * If there wasn't enough space for our winentries,
246 * forget about the empty space
248 if (slotcount < wincnt)
252 * Check for Win95 long filename entry
254 if (dep->deAttributes == ATTR_WIN95) {
255 if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
258 chksum = winChkName((const u_char *)cnp->cn_nameptr,
260 (struct winentry *)dep,
262 pmp->pm_flags & MSDOSFSMNT_U2WTABLE,
264 pmp->pm_flags & MSDOSFSMNT_ULTABLE,
270 * Ignore volume labels (anywhere, not just
271 * the root directory).
273 if (dep->deAttributes & ATTR_VOLUME) {
279 * Check for a checksum or name match
281 if (chksum != winChksum(dep->deName)
282 && (!olddos || bcmp(dosfilename, dep->deName, 11))) {
287 printf("msdosfs_lookup(): match blkoff %d, diroff %d\n",
291 * Remember where this directory
292 * entry came from for whoever did
295 dp->de_fndoffset = diroff;
296 dp->de_fndcnt = wincnt - 1;
300 } /* for (blkoff = 0; .... */
302 * Release the buffer holding the directory cluster just
306 } /* for (frcn = 0; ; frcn++) */
310 * We hold no disk buffers at this point.
314 * Fixup the slot description to point to the place where
315 * we might put the new DOS direntry (putting the Win95
316 * long name entries before that)
322 if (wincnt > slotcount)
323 slotoffset += sizeof(struct direntry) * (wincnt - slotcount);
326 * If we get here we didn't find the entry we were looking for. But
327 * that's ok if we are creating or renaming and are at the end of
328 * the pathname and the directory hasn't been removed.
331 printf("msdosfs_lookup(): op %d, refcnt %ld\n",
332 nameiop, dp->de_refcnt);
333 printf(" slotcount %d, slotoffset %d\n",
334 slotcount, slotoffset);
336 if ((nameiop == NAMEI_CREATE || nameiop == NAMEI_RENAME) &&
337 (flags & CNP_ISLASTCN) && dp->de_refcnt != 0) {
339 * Access for write is interpreted as allowing
340 * creation of files in the directory.
342 error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred, cnp->cn_td);
346 * Return an indication of where the new directory
347 * entry should be put.
349 dp->de_fndoffset = slotoffset;
350 dp->de_fndcnt = wincnt - 1;
353 * We return with the directory locked, so that
354 * the parameters we set up above will still be
355 * valid if we actually decide to do a direnter().
356 * We return ni_vp == NULL to indicate that the entry
357 * does not currently exist; we leave a pointer to
358 * the (locked) directory inode in ndp->ni_dvp.
359 * The pathname buffer is saved so that the name
360 * can be obtained later.
362 * NB - if the directory is unlocked, then this
363 * information cannot be used.
365 cnp->cn_flags |= CNP_SAVENAME;
367 VOP_UNLOCK(vdp, 0, td);
368 cnp->cn_flags |= CNP_PDIRUNLOCK;
370 return (EJUSTRETURN);
373 * Insert name into cache (as non-existent) if appropriate.
375 if ((cnp->cn_flags & CNP_MAKEENTRY) && nameiop != NAMEI_CREATE)
376 cache_enter(vdp, *vpp, cnp);
381 * NOTE: We still have the buffer with matched directory entry at
384 isadir = dep->deAttributes & ATTR_DIRECTORY;
385 scn = getushort(dep->deStartCluster);
387 scn |= getushort(dep->deHighClust) << 16;
388 if (scn == pmp->pm_rootdirblk) {
390 * There should actually be 0 here.
391 * Just ignore the error.
399 if (cluster == MSDOSFSROOT)
400 blkoff = MSDOSFSROOT_OFS;
403 } else if (cluster == MSDOSFSROOT)
407 * Now release buf to allow deget to read the entry again.
408 * Reserving it here and giving it to deget could result
416 * If we entered at foundroot, then we are looking for the . or ..
417 * entry of the filesystems root directory. isadir and scn were
418 * setup before jumping here. And, bp is already null.
420 if (FAT32(pmp) && scn == MSDOSFSROOT)
421 scn = pmp->pm_rootdirblk;
424 * If deleting, and at end of pathname, return
425 * parameters which can be used to remove file.
426 * If the wantparent flag isn't set, we return only
427 * the directory (in ndp->ni_dvp), otherwise we go
428 * on and lock the inode, being careful with ".".
430 if (nameiop == NAMEI_DELETE && (flags & CNP_ISLASTCN)) {
432 * Don't allow deleting the root.
434 if (blkoff == MSDOSFSROOT_OFS)
435 return EROFS; /* really? XXX */
438 * Write access to directory required to delete files.
440 error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred, cnp->cn_td);
445 * Return pointer to current entry in dp->i_offset.
446 * Save directory inode pointer in ndp->ni_dvp for dirremove().
448 if (dp->de_StartCluster == scn && isadir) { /* "." */
453 error = deget(pmp, cluster, blkoff, &tdp);
458 VOP_UNLOCK(vdp, 0, td);
459 cnp->cn_flags |= CNP_PDIRUNLOCK;
465 * If rewriting (RENAME), return the inode and the
466 * information required to rewrite the present directory
467 * Must get inode of directory entry to verify it's a
468 * regular file, or empty directory.
470 if (nameiop == NAMEI_RENAME && wantparent &&
471 (flags & CNP_ISLASTCN)) {
472 if (blkoff == MSDOSFSROOT_OFS)
473 return EROFS; /* really? XXX */
475 error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred, cnp->cn_td);
480 * Careful about locking second inode.
481 * This can only occur if the target is ".".
483 if (dp->de_StartCluster == scn && isadir)
486 if ((error = deget(pmp, cluster, blkoff, &tdp)) != 0)
489 cnp->cn_flags |= CNP_SAVENAME;
491 VOP_UNLOCK(vdp, 0, td);
492 cnp->cn_flags |= CNP_PDIRUNLOCK;
498 * Step through the translation in the name. We do not `vput' the
499 * directory because we may need it again if a symbolic link
500 * is relative to the current directory. Instead we save it
501 * unlocked as "pdp". We must get the target inode before unlocking
502 * the directory to insure that the inode will not be removed
503 * before we get it. We prevent deadlock by always fetching
504 * inodes from the root, moving down the directory tree. Thus
505 * when following backward pointers ".." we must unlock the
506 * parent directory before getting the requested directory.
507 * There is a potential race condition here if both the current
508 * and parent directories are removed before the VFS_VGET for the
509 * inode associated with ".." returns. We hope that this occurs
510 * infrequently since we cannot avoid this race condition without
511 * implementing a sophisticated deadlock detection algorithm.
512 * Note also that this simple deadlock detection scheme will not
513 * work if the file system has any hard links other than ".."
514 * that point backwards in the directory structure.
517 if (flags & CNP_ISDOTDOT) {
518 VOP_UNLOCK(pdp, 0, td);
519 cnp->cn_flags |= CNP_PDIRUNLOCK;
520 error = deget(pmp, cluster, blkoff, &tdp);
522 vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
523 cnp->cn_flags &= ~CNP_PDIRUNLOCK;
526 if (lockparent && (flags & CNP_ISLASTCN)) {
527 error = vn_lock(pdp, LK_EXCLUSIVE, td);
532 cnp->cn_flags &= ~CNP_PDIRUNLOCK;
535 } else if (dp->de_StartCluster == scn && isadir) {
536 vref(vdp); /* we want ourself, ie "." */
539 if ((error = deget(pmp, cluster, blkoff, &tdp)) != 0)
541 if (!lockparent || !(flags & CNP_ISLASTCN)) {
542 VOP_UNLOCK(pdp, 0, td);
543 cnp->cn_flags |= CNP_PDIRUNLOCK;
549 * Insert name into cache if appropriate.
551 if (cnp->cn_flags & CNP_MAKEENTRY)
552 cache_enter(vdp, *vpp, cnp);
557 * dep - directory entry to copy into the directory
558 * ddep - directory to add to
559 * depp - return the address of the denode for the created directory entry
561 * cnp - componentname needed for Win95 long filenames
564 createde(struct denode *dep, struct denode *ddep, struct denode **depp,
565 struct componentname *cnp)
568 u_long dirclust, diroffset;
569 struct direntry *ndep;
570 struct msdosfsmount *pmp = ddep->de_pmp;
576 printf("createde(dep %p, ddep %p, depp %p, cnp %p)\n",
577 dep, ddep, depp, cnp);
581 * If no space left in the directory then allocate another cluster
582 * and chain it onto the end of the file. There is one exception
583 * to this. That is, if the root directory has no more space it
584 * can NOT be expanded. extendfile() checks for and fails attempts
585 * to extend the root directory. We just return an error in that
588 if (ddep->de_fndoffset >= ddep->de_FileSize) {
589 diroffset = ddep->de_fndoffset + sizeof(struct direntry)
591 dirclust = de_clcount(pmp, diroffset);
592 error = extendfile(ddep, dirclust, 0, 0, DE_CLEAR);
594 (void)detrunc(ddep, ddep->de_FileSize, 0, NULL);
599 * Update the size of the directory
601 ddep->de_FileSize += de_cn2off(pmp, dirclust);
605 * We just read in the cluster with space. Copy the new directory
606 * entry in. Then write it to disk. NOTE: DOS directories
607 * do not get smaller as clusters are emptied.
609 error = pcbmap(ddep, de_cluster(pmp, ddep->de_fndoffset),
610 &bn, &dirclust, &blsize);
613 diroffset = ddep->de_fndoffset;
614 if (dirclust != MSDOSFSROOT)
615 diroffset &= pmp->pm_crbomask;
616 if ((error = bread(pmp->pm_devvp, bn, blsize, &bp)) != 0) {
620 ndep = bptoep(pmp, bp, ddep->de_fndoffset);
622 DE_EXTERNALIZE(ndep, dep);
625 * Now write the Win95 long name
627 if (ddep->de_fndcnt > 0) {
628 u_int8_t chksum = winChksum(ndep->deName);
629 const u_char *un = (const u_char *)cnp->cn_nameptr;
630 int unlen = cnp->cn_namelen;
633 while (--ddep->de_fndcnt >= 0) {
634 if (!(ddep->de_fndoffset & pmp->pm_crbomask)) {
635 if ((error = bwrite(bp)) != 0)
638 ddep->de_fndoffset -= sizeof(struct direntry);
646 error = bread(pmp->pm_devvp, bn, blsize, &bp);
651 ndep = bptoep(pmp, bp, ddep->de_fndoffset);
654 ddep->de_fndoffset -= sizeof(struct direntry);
656 if (!unix2winfn(un, unlen, (struct winentry *)ndep,
658 pmp->pm_flags & MSDOSFSMNT_U2WTABLE,
664 if ((error = bwrite(bp)) != 0)
668 * If they want us to return with the denode gotten.
671 if (dep->de_Attributes & ATTR_DIRECTORY) {
672 dirclust = dep->de_StartCluster;
673 if (FAT32(pmp) && dirclust == pmp->pm_rootdirblk)
674 dirclust = MSDOSFSROOT;
675 if (dirclust == MSDOSFSROOT)
676 diroffset = MSDOSFSROOT_OFS;
680 return deget(pmp, dirclust, diroffset, depp);
687 * Be sure a directory is empty except for "." and "..". Return 1 if empty,
688 * return 0 if not empty or error.
691 dosdirempty(struct denode *dep)
698 struct msdosfsmount *pmp = dep->de_pmp;
699 struct direntry *dentp;
702 * Since the filesize field in directory entries for a directory is
703 * zero, we just have to feel our way through the directory until
704 * we hit end of file.
706 for (cn = 0;; cn++) {
707 if ((error = pcbmap(dep, cn, &bn, 0, &blsize)) != 0) {
709 return (1); /* it's empty */
712 error = bread(pmp->pm_devvp, bn, blsize, &bp);
717 for (dentp = (struct direntry *)bp->b_data;
718 (char *)dentp < bp->b_data + blsize;
720 if (dentp->deName[0] != SLOT_DELETED &&
721 (dentp->deAttributes & ATTR_VOLUME) == 0) {
723 * In dos directories an entry whose name
724 * starts with SLOT_EMPTY (0) starts the
725 * beginning of the unused part of the
726 * directory, so we can just return that it
729 if (dentp->deName[0] == SLOT_EMPTY) {
734 * Any names other than "." and ".." in a
735 * directory mean it is not empty.
737 if (bcmp(dentp->deName, ". ", 11) &&
738 bcmp(dentp->deName, ".. ", 11)) {
741 printf("dosdirempty(): entry found %02x, %02x\n",
742 dentp->deName[0], dentp->deName[1]);
744 return (0); /* not empty */
754 * Check to see if the directory described by target is in some
755 * subdirectory of source. This prevents something like the following from
756 * succeeding and leaving a bunch or files and directories orphaned. mv
757 * /a/b/c /a/b/c/d/e/f Where c and f are directories.
759 * source - the inode for /a/b/c
760 * target - the inode for /a/b/c/d/e/f
762 * Returns 0 if target is NOT a subdirectory of source.
763 * Otherwise returns a non-zero error number.
764 * The target inode is always unlocked on return.
767 doscheckpath(struct denode *source, struct denode *target)
770 struct msdosfsmount *pmp;
773 struct buf *bp = NULL;
777 if ((target->de_Attributes & ATTR_DIRECTORY) == 0 ||
778 (source->de_Attributes & ATTR_DIRECTORY) == 0) {
782 if (dep->de_StartCluster == source->de_StartCluster) {
786 if (dep->de_StartCluster == MSDOSFSROOT)
790 if (pmp != source->de_pmp)
791 panic("doscheckpath: source and target on different filesystems");
793 if (FAT32(pmp) && dep->de_StartCluster == pmp->pm_rootdirblk)
797 if ((dep->de_Attributes & ATTR_DIRECTORY) == 0) {
801 scn = dep->de_StartCluster;
802 error = bread(pmp->pm_devvp, cntobn(pmp, scn),
803 pmp->pm_bpcluster, &bp);
807 ep = (struct direntry *) bp->b_data + 1;
808 if ((ep->deAttributes & ATTR_DIRECTORY) == 0 ||
809 bcmp(ep->deName, ".. ", 11) != 0) {
813 scn = getushort(ep->deStartCluster);
815 scn |= getushort(ep->deHighClust) << 16;
817 if (scn == source->de_StartCluster) {
821 if (scn == MSDOSFSROOT)
823 if (FAT32(pmp) && scn == pmp->pm_rootdirblk) {
825 * scn should be 0 in this case,
826 * but we silently ignore the error.
834 /* NOTE: deget() clears dep on error */
835 if ((error = deget(pmp, scn, 0, &dep)) != 0)
841 if (error == ENOTDIR)
842 printf("doscheckpath(): .. not a directory?\n");
849 * Read in the disk block containing the directory entry (dirclu, dirofs)
850 * and return the address of the buf header, and the address of the
851 * directory entry within the block.
854 readep(struct msdosfsmount *pmp, u_long dirclust, u_long diroffset,
855 struct buf **bpp, struct direntry **epp)
861 blsize = pmp->pm_bpcluster;
862 if (dirclust == MSDOSFSROOT
863 && de_blk(pmp, diroffset + blsize) > pmp->pm_rootdirsize)
864 blsize = de_bn2off(pmp, pmp->pm_rootdirsize) & pmp->pm_crbomask;
865 bn = detobn(pmp, dirclust, diroffset);
866 if ((error = bread(pmp->pm_devvp, bn, blsize, bpp)) != 0) {
872 *epp = bptoep(pmp, *bpp, diroffset);
877 * Read in the disk block containing the directory entry dep came from and
878 * return the address of the buf header, and the address of the directory
879 * entry within the block.
882 readde(struct denode *dep, struct buf **bpp, struct direntry **epp)
884 return (readep(dep->de_pmp, dep->de_dirclust, dep->de_diroffset,
889 * Remove a directory entry. At this point the file represented by the
890 * directory entry to be removed is still full length until noone has it
891 * open. When the file no longer being used msdosfs_inactive() is called
892 * and will truncate the file to 0 length. When the vnode containing the
893 * denode is needed for some other purpose by VFS it will call
894 * msdosfs_reclaim() which will remove the denode from the denode cache.
897 removede(struct denode *pdep, /* directory where the entry is removed */
898 struct denode *dep) /* file to be removed */
905 struct msdosfsmount *pmp = pdep->de_pmp;
906 u_long offset = pdep->de_fndoffset;
909 printf("removede(): filename %s, dep %p, offset %08lx\n",
910 dep->de_Name, dep, offset);
914 offset += sizeof(struct direntry);
916 offset -= sizeof(struct direntry);
917 error = pcbmap(pdep, de_cluster(pmp, offset), &bn, 0, &blsize);
920 error = bread(pmp->pm_devvp, bn, blsize, &bp);
925 ep = bptoep(pmp, bp, offset);
927 * Check whether, if we came here the second time, i.e.
928 * when underflowing into the previous block, the last
929 * entry in this block is a longfilename entry, too.
931 if (ep->deAttributes != ATTR_WIN95
932 && offset != pdep->de_fndoffset) {
936 offset += sizeof(struct direntry);
939 * We are a bit agressive here in that we delete any Win95
940 * entries preceding this entry, not just the ones we "own".
941 * Since these presumably aren't valid anyway,
942 * there should be no harm.
944 offset -= sizeof(struct direntry);
945 ep--->deName[0] = SLOT_DELETED;
946 if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95)
947 || !(offset & pmp->pm_crbomask)
948 || ep->deAttributes != ATTR_WIN95)
951 if ((error = bwrite(bp)) != 0)
953 } while (!(pmp->pm_flags & MSDOSFSMNT_NOWIN95)
954 && !(offset & pmp->pm_crbomask)
960 * Create a unique DOS name in dvp
963 uniqdosname(struct denode *dep, struct componentname *cnp, u_char *cp)
965 struct msdosfsmount *pmp = dep->de_pmp;
966 struct direntry *dentp;
974 if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
975 return (unix2dosfn((const u_char *)cnp->cn_nameptr, cp,
977 pmp->pm_flags & MSDOSFSMNT_U2WTABLE, pmp->pm_u2d,
978 pmp->pm_flags & MSDOSFSMNT_ULTABLE, pmp->pm_lu) ?
981 for (gen = 1;; gen++) {
983 * Generate DOS name with generation number
985 if (!unix2dosfn((const u_char *)cnp->cn_nameptr, cp,
986 cnp->cn_namelen, gen,
987 pmp->pm_flags & MSDOSFSMNT_U2WTABLE, pmp->pm_u2d,
988 pmp->pm_flags & MSDOSFSMNT_ULTABLE, pmp->pm_lu))
989 return gen == 1 ? EINVAL : EEXIST;
992 * Now look for a dir entry with this exact name
994 for (cn = error = 0; !error; cn++) {
995 if ((error = pcbmap(dep, cn, &bn, 0, &blsize)) != 0) {
996 if (error == E2BIG) /* EOF reached and not found */
1000 error = bread(pmp->pm_devvp, bn, blsize, &bp);
1005 for (dentp = (struct direntry *)bp->b_data;
1006 (char *)dentp < bp->b_data + blsize;
1008 if (dentp->deName[0] == SLOT_EMPTY) {
1010 * Last used entry and not found
1016 * Ignore volume labels and Win95 entries
1018 if (dentp->deAttributes & ATTR_VOLUME)
1020 if (!bcmp(dentp->deName, cp, 11)) {
1031 * Find any Win'95 long filename entry in directory dep
1034 findwin95(struct denode *dep)
1036 struct msdosfsmount *pmp = dep->de_pmp;
1037 struct direntry *dentp;
1045 * Read through the directory looking for Win'95 entries
1046 * Note: Error currently handled just as EOF XXX
1048 for (cn = 0;; cn++) {
1049 if (pcbmap(dep, cn, &bn, 0, &blsize))
1051 if (bread(pmp->pm_devvp, bn, blsize, &bp)) {
1055 for (dentp = (struct direntry *)bp->b_data;
1056 (char *)dentp < bp->b_data + blsize;
1058 if (dentp->deName[0] == SLOT_EMPTY) {
1060 * Last used entry and not found
1065 if (dentp->deName[0] == SLOT_DELETED) {
1067 * Ignore deleted files
1068 * Note: might be an indication of Win'95 anyway XXX
1072 if (dentp->deAttributes == ATTR_WIN95) {