dir.c revision 203874 
1/*
2 * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank
3 * Copyright (c) 1995 Martin Husemann
4 * Some structure declaration borrowed from Paul Popelka
5 * (paulp@uts.amdahl.com), see /sys/msdosfs/ for reference.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28
29#include <sys/cdefs.h>
30#ifndef lint
31__RCSID("$NetBSD: dir.c,v 1.14 1998/08/25 19:18:15 ross Exp $");
32static const char rcsid[] =
33  "$FreeBSD: head/sbin/fsck_msdosfs/dir.c 203874 2010-02-14 12:31:28Z kib $";
34#endif /* not lint */
35
36#include <stdio.h>
37#include <stdlib.h>
38#include <string.h>
39#include <ctype.h>
40#include <unistd.h>
41#include <time.h>
42
43#include <sys/param.h>
44
45#include "ext.h"
46#include "fsutil.h"
47
48#define	SLOT_EMPTY	0x00		/* slot has never been used */
49#define	SLOT_E5		0x05		/* the real value is 0xe5 */
50#define	SLOT_DELETED	0xe5		/* file in this slot deleted */
51
52#define	ATTR_NORMAL	0x00		/* normal file */
53#define	ATTR_READONLY	0x01		/* file is readonly */
54#define	ATTR_HIDDEN	0x02		/* file is hidden */
55#define	ATTR_SYSTEM	0x04		/* file is a system file */
56#define	ATTR_VOLUME	0x08		/* entry is a volume label */
57#define	ATTR_DIRECTORY	0x10		/* entry is a directory name */
58#define	ATTR_ARCHIVE	0x20		/* file is new or modified */
59
60#define	ATTR_WIN95	0x0f		/* long name record */
61
62/*
63 * This is the format of the contents of the deTime field in the direntry
64 * structure.
65 * We don't use bitfields because we don't know how compilers for
66 * arbitrary machines will lay them out.
67 */
68#define DT_2SECONDS_MASK	0x1F	/* seconds divided by 2 */
69#define DT_2SECONDS_SHIFT	0
70#define DT_MINUTES_MASK		0x7E0	/* minutes */
71#define DT_MINUTES_SHIFT	5
72#define DT_HOURS_MASK		0xF800	/* hours */
73#define DT_HOURS_SHIFT		11
74
75/*
76 * This is the format of the contents of the deDate field in the direntry
77 * structure.
78 */
79#define DD_DAY_MASK		0x1F	/* day of month */
80#define DD_DAY_SHIFT		0
81#define DD_MONTH_MASK		0x1E0	/* month */
82#define DD_MONTH_SHIFT		5
83#define DD_YEAR_MASK		0xFE00	/* year - 1980 */
84#define DD_YEAR_SHIFT		9
85
86
87/* dir.c */
88static struct dosDirEntry *newDosDirEntry(void);
89static void freeDosDirEntry(struct dosDirEntry *);
90static struct dirTodoNode *newDirTodo(void);
91static void freeDirTodo(struct dirTodoNode *);
92static char *fullpath(struct dosDirEntry *);
93static u_char calcShortSum(u_char *);
94static int delete(int, struct bootblock *, struct fatEntry *, cl_t, int,
95    cl_t, int, int);
96static int removede(int, struct bootblock *, struct fatEntry *, u_char *,
97    u_char *, cl_t, cl_t, cl_t, char *, int);
98static int checksize(struct bootblock *, struct fatEntry *, u_char *,
99    struct dosDirEntry *);
100static int readDosDirSection(int, struct bootblock *, struct fatEntry *,
101    struct dosDirEntry *);
102
103/*
104 * Manage free dosDirEntry structures.
105 */
106static struct dosDirEntry *freede;
107
108static struct dosDirEntry *
109newDosDirEntry(void)
110{
111	struct dosDirEntry *de;
112
113	if (!(de = freede)) {
114		if (!(de = (struct dosDirEntry *)malloc(sizeof *de)))
115			return 0;
116	} else
117		freede = de->next;
118	return de;
119}
120
121static void
122freeDosDirEntry(struct dosDirEntry *de)
123{
124	de->next = freede;
125	freede = de;
126}
127
128/*
129 * The same for dirTodoNode structures.
130 */
131static struct dirTodoNode *freedt;
132
133static struct dirTodoNode *
134newDirTodo(void)
135{
136	struct dirTodoNode *dt;
137
138	if (!(dt = freedt)) {
139		if (!(dt = (struct dirTodoNode *)malloc(sizeof *dt)))
140			return 0;
141	} else
142		freedt = dt->next;
143	return dt;
144}
145
146static void
147freeDirTodo(struct dirTodoNode *dt)
148{
149	dt->next = freedt;
150	freedt = dt;
151}
152
153/*
154 * The stack of unread directories
155 */
156struct dirTodoNode *pendingDirectories = NULL;
157
158/*
159 * Return the full pathname for a directory entry.
160 */
161static char *
162fullpath(struct dosDirEntry *dir)
163{
164	static char namebuf[MAXPATHLEN + 1];
165	char *cp, *np;
166	int nl;
167
168	cp = namebuf + sizeof namebuf - 1;
169	*cp = '\0';
170	do {
171		np = dir->lname[0] ? dir->lname : dir->name;
172		nl = strlen(np);
173		if ((cp -= nl) <= namebuf + 1)
174			break;
175		memcpy(cp, np, nl);
176		*--cp = '/';
177	} while ((dir = dir->parent) != NULL);
178	if (dir)
179		*--cp = '?';
180	else
181		cp++;
182	return cp;
183}
184
185/*
186 * Calculate a checksum over an 8.3 alias name
187 */
188static u_char
189calcShortSum(u_char *p)
190{
191	u_char sum = 0;
192	int i;
193
194	for (i = 0; i < 11; i++) {
195		sum = (sum << 7)|(sum >> 1);	/* rotate right */
196		sum += p[i];
197	}
198
199	return sum;
200}
201
202/*
203 * Global variables temporarily used during a directory scan
204 */
205static char longName[DOSLONGNAMELEN] = "";
206static u_char *buffer = NULL;
207static u_char *delbuf = NULL;
208
209struct dosDirEntry *rootDir;
210static struct dosDirEntry *lostDir;
211
212/*
213 * Init internal state for a new directory scan.
214 */
215int
216resetDosDirSection(struct bootblock *boot, struct fatEntry *fat)
217{
218	int b1, b2;
219	cl_t cl;
220	int ret = FSOK;
221
222	b1 = boot->bpbRootDirEnts * 32;
223	b2 = boot->bpbSecPerClust * boot->bpbBytesPerSec;
224
225	if ((buffer = malloc( b1 > b2 ? b1 : b2)) == NULL) {
226		perror("No space for directory buffer");
227		return FSFATAL;
228	}
229
230	if ((delbuf = malloc(b2)) == NULL) {
231		free(buffer);
232		perror("No space for directory delbuf");
233		return FSFATAL;
234	}
235
236	if ((rootDir = newDosDirEntry()) == NULL) {
237		free(buffer);
238		free(delbuf);
239		perror("No space for directory entry");
240		return FSFATAL;
241	}
242
243	memset(rootDir, 0, sizeof *rootDir);
244	if (boot->flags & FAT32) {
245		if (boot->bpbRootClust < CLUST_FIRST || boot->bpbRootClust >= boot->NumClusters) {
246			pfatal("Root directory starts with cluster out of range(%u)",
247			       boot->bpbRootClust);
248			return FSFATAL;
249		}
250		cl = fat[boot->bpbRootClust].next;
251		if (cl < CLUST_FIRST
252		    || (cl >= CLUST_RSRVD && cl< CLUST_EOFS)
253		    || fat[boot->bpbRootClust].head != boot->bpbRootClust) {
254			if (cl == CLUST_FREE)
255				pwarn("Root directory starts with free cluster\n");
256			else if (cl >= CLUST_RSRVD)
257				pwarn("Root directory starts with cluster marked %s\n",
258				      rsrvdcltype(cl));
259			else {
260				pfatal("Root directory doesn't start a cluster chain");
261				return FSFATAL;
262			}
263			if (ask(1, "Fix")) {
264				fat[boot->bpbRootClust].next = CLUST_FREE;
265				ret = FSFATMOD;
266			} else
267				ret = FSFATAL;
268		}
269
270		fat[boot->bpbRootClust].flags |= FAT_USED;
271		rootDir->head = boot->bpbRootClust;
272	}
273
274	return ret;
275}
276
277/*
278 * Cleanup after a directory scan
279 */
280void
281finishDosDirSection(void)
282{
283	struct dirTodoNode *p, *np;
284	struct dosDirEntry *d, *nd;
285
286	for (p = pendingDirectories; p; p = np) {
287		np = p->next;
288		freeDirTodo(p);
289	}
290	pendingDirectories = 0;
291	for (d = rootDir; d; d = nd) {
292		if ((nd = d->child) != NULL) {
293			d->child = 0;
294			continue;
295		}
296		if (!(nd = d->next))
297			nd = d->parent;
298		freeDosDirEntry(d);
299	}
300	rootDir = lostDir = NULL;
301	free(buffer);
302	free(delbuf);
303	buffer = NULL;
304	delbuf = NULL;
305}
306
307/*
308 * Delete directory entries between startcl, startoff and endcl, endoff.
309 */
310static int
311delete(int f, struct bootblock *boot, struct fatEntry *fat, cl_t startcl,
312    int startoff, cl_t endcl, int endoff, int notlast)
313{
314	u_char *s, *e;
315	off_t off;
316	int clsz = boot->bpbSecPerClust * boot->bpbBytesPerSec;
317
318	s = delbuf + startoff;
319	e = delbuf + clsz;
320	while (startcl >= CLUST_FIRST && startcl < boot->NumClusters) {
321		if (startcl == endcl) {
322			if (notlast)
323				break;
324			e = delbuf + endoff;
325		}
326		off = startcl * boot->bpbSecPerClust + boot->ClusterOffset;
327		off *= boot->bpbBytesPerSec;
328		if (lseek(f, off, SEEK_SET) != off
329		    || read(f, delbuf, clsz) != clsz) {
330			perror("Unable to read directory");
331			return FSFATAL;
332		}
333		while (s < e) {
334			*s = SLOT_DELETED;
335			s += 32;
336		}
337		if (lseek(f, off, SEEK_SET) != off
338		    || write(f, delbuf, clsz) != clsz) {
339			perror("Unable to write directory");
340			return FSFATAL;
341		}
342		if (startcl == endcl)
343			break;
344		startcl = fat[startcl].next;
345		s = delbuf;
346	}
347	return FSOK;
348}
349
350static int
351removede(int f, struct bootblock *boot, struct fatEntry *fat, u_char *start,
352    u_char *end, cl_t startcl, cl_t endcl, cl_t curcl, char *path, int type)
353{
354	switch (type) {
355	case 0:
356		pwarn("Invalid long filename entry for %s\n", path);
357		break;
358	case 1:
359		pwarn("Invalid long filename entry at end of directory %s\n", path);
360		break;
361	case 2:
362		pwarn("Invalid long filename entry for volume label\n");
363		break;
364	}
365	if (ask(0, "Remove")) {
366		if (startcl != curcl) {
367			if (delete(f, boot, fat,
368				   startcl, start - buffer,
369				   endcl, end - buffer,
370				   endcl == curcl) == FSFATAL)
371				return FSFATAL;
372			start = buffer;
373		}
374		/* startcl is < CLUST_FIRST for !fat32 root */
375		if ((endcl == curcl) || (startcl < CLUST_FIRST))
376			for (; start < end; start += 32)
377				*start = SLOT_DELETED;
378		return FSDIRMOD;
379	}
380	return FSERROR;
381}
382
383/*
384 * Check an in-memory file entry
385 */
386static int
387checksize(struct bootblock *boot, struct fatEntry *fat, u_char *p,
388    struct dosDirEntry *dir)
389{
390	/*
391	 * Check size on ordinary files
392	 */
393	u_int32_t physicalSize;
394
395	if (dir->head == CLUST_FREE)
396		physicalSize = 0;
397	else {
398		if (dir->head < CLUST_FIRST || dir->head >= boot->NumClusters)
399			return FSERROR;
400		physicalSize = fat[dir->head].length * boot->ClusterSize;
401	}
402	if (physicalSize < dir->size) {
403		pwarn("size of %s is %u, should at most be %u\n",
404		      fullpath(dir), dir->size, physicalSize);
405		if (ask(1, "Truncate")) {
406			dir->size = physicalSize;
407			p[28] = (u_char)physicalSize;
408			p[29] = (u_char)(physicalSize >> 8);
409			p[30] = (u_char)(physicalSize >> 16);
410			p[31] = (u_char)(physicalSize >> 24);
411			return FSDIRMOD;
412		} else
413			return FSERROR;
414	} else if (physicalSize - dir->size >= boot->ClusterSize) {
415		pwarn("%s has too many clusters allocated\n",
416		      fullpath(dir));
417		if (ask(1, "Drop superfluous clusters")) {
418			cl_t cl;
419			u_int32_t sz = 0;
420
421			for (cl = dir->head; (sz += boot->ClusterSize) < dir->size;)
422				cl = fat[cl].next;
423			clearchain(boot, fat, fat[cl].next);
424			fat[cl].next = CLUST_EOF;
425			return FSFATMOD;
426		} else
427			return FSERROR;
428	}
429	return FSOK;
430}
431
432/*
433 * Read a directory and
434 *   - resolve long name records
435 *   - enter file and directory records into the parent's list
436 *   - push directories onto the todo-stack
437 */
438static int
439readDosDirSection(int f, struct bootblock *boot, struct fatEntry *fat,
440    struct dosDirEntry *dir)
441{
442	struct dosDirEntry dirent, *d;
443	u_char *p, *vallfn, *invlfn, *empty;
444	off_t off;
445	int i, j, k, last;
446	cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0;
447	char *t;
448	u_int lidx = 0;
449	int shortSum;
450	int mod = FSOK;
451#define	THISMOD	0x8000			/* Only used within this routine */
452
453	cl = dir->head;
454	if (dir->parent && (cl < CLUST_FIRST || cl >= boot->NumClusters)) {
455		/*
456		 * Already handled somewhere else.
457		 */
458		return FSOK;
459	}
460	shortSum = -1;
461	vallfn = invlfn = empty = NULL;
462	do {
463		if (!(boot->flags & FAT32) && !dir->parent) {
464			last = boot->bpbRootDirEnts * 32;
465			off = boot->bpbResSectors + boot->bpbFATs * boot->FATsecs;
466		} else {
467			last = boot->bpbSecPerClust * boot->bpbBytesPerSec;
468			off = cl * boot->bpbSecPerClust + boot->ClusterOffset;
469		}
470
471		off *= boot->bpbBytesPerSec;
472		if (lseek(f, off, SEEK_SET) != off
473		    || read(f, buffer, last) != last) {
474			perror("Unable to read directory");
475			return FSFATAL;
476		}
477		last /= 32;
478		/*
479		 * Check `.' and `..' entries here?			XXX
480		 */
481		for (p = buffer, i = 0; i < last; i++, p += 32) {
482			if (dir->fsckflags & DIREMPWARN) {
483				*p = SLOT_EMPTY;
484				continue;
485			}
486
487			if (*p == SLOT_EMPTY || *p == SLOT_DELETED) {
488				if (*p == SLOT_EMPTY) {
489					dir->fsckflags |= DIREMPTY;
490					empty = p;
491					empcl = cl;
492				}
493				continue;
494			}
495
496			if (dir->fsckflags & DIREMPTY) {
497				if (!(dir->fsckflags & DIREMPWARN)) {
498					pwarn("%s has entries after end of directory\n",
499					      fullpath(dir));
500					if (ask(1, "Extend")) {
501						u_char *q;
502
503						dir->fsckflags &= ~DIREMPTY;
504						if (delete(f, boot, fat,
505							   empcl, empty - buffer,
506							   cl, p - buffer, 1) == FSFATAL)
507							return FSFATAL;
508						q = empcl == cl ? empty : buffer;
509						for (; q < p; q += 32)
510							*q = SLOT_DELETED;
511						mod |= THISMOD|FSDIRMOD;
512					} else if (ask(0, "Truncate"))
513						dir->fsckflags |= DIREMPWARN;
514				}
515				if (dir->fsckflags & DIREMPWARN) {
516					*p = SLOT_DELETED;
517					mod |= THISMOD|FSDIRMOD;
518					continue;
519				} else if (dir->fsckflags & DIREMPTY)
520					mod |= FSERROR;
521				empty = NULL;
522			}
523
524			if (p[11] == ATTR_WIN95) {
525				if (*p & LRFIRST) {
526					if (shortSum != -1) {
527						if (!invlfn) {
528							invlfn = vallfn;
529							invcl = valcl;
530						}
531					}
532					memset(longName, 0, sizeof longName);
533					shortSum = p[13];
534					vallfn = p;
535					valcl = cl;
536				} else if (shortSum != p[13]
537					   || lidx != (*p & LRNOMASK)) {
538					if (!invlfn) {
539						invlfn = vallfn;
540						invcl = valcl;
541					}
542					if (!invlfn) {
543						invlfn = p;
544						invcl = cl;
545					}
546					vallfn = NULL;
547				}
548				lidx = *p & LRNOMASK;
549				t = longName + --lidx * 13;
550				for (k = 1; k < 11 && t < longName + sizeof(longName); k += 2) {
551					if (!p[k] && !p[k + 1])
552						break;
553					*t++ = p[k];
554					/*
555					 * Warn about those unusable chars in msdosfs here?	XXX
556					 */
557					if (p[k + 1])
558						t[-1] = '?';
559				}
560				if (k >= 11)
561					for (k = 14; k < 26 && t < longName + sizeof(longName); k += 2) {
562						if (!p[k] && !p[k + 1])
563							break;
564						*t++ = p[k];
565						if (p[k + 1])
566							t[-1] = '?';
567					}
568				if (k >= 26)
569					for (k = 28; k < 32 && t < longName + sizeof(longName); k += 2) {
570						if (!p[k] && !p[k + 1])
571							break;
572						*t++ = p[k];
573						if (p[k + 1])
574							t[-1] = '?';
575					}
576				if (t >= longName + sizeof(longName)) {
577					pwarn("long filename too long\n");
578					if (!invlfn) {
579						invlfn = vallfn;
580						invcl = valcl;
581					}
582					vallfn = NULL;
583				}
584				if (p[26] | (p[27] << 8)) {
585					pwarn("long filename record cluster start != 0\n");
586					if (!invlfn) {
587						invlfn = vallfn;
588						invcl = cl;
589					}
590					vallfn = NULL;
591				}
592				continue;	/* long records don't carry further
593						 * information */
594			}
595
596			/*
597			 * This is a standard msdosfs directory entry.
598			 */
599			memset(&dirent, 0, sizeof dirent);
600
601			/*
602			 * it's a short name record, but we need to know
603			 * more, so get the flags first.
604			 */
605			dirent.flags = p[11];
606
607			/*
608			 * Translate from 850 to ISO here		XXX
609			 */
610			for (j = 0; j < 8; j++)
611				dirent.name[j] = p[j];
612			dirent.name[8] = '\0';
613			for (k = 7; k >= 0 && dirent.name[k] == ' '; k--)
614				dirent.name[k] = '\0';
615			if (dirent.name[k] != '\0')
616				k++;
617			if (dirent.name[0] == SLOT_E5)
618				dirent.name[0] = 0xe5;
619
620			if (dirent.flags & ATTR_VOLUME) {
621				if (vallfn || invlfn) {
622					mod |= removede(f, boot, fat,
623							invlfn ? invlfn : vallfn, p,
624							invlfn ? invcl : valcl, -1, 0,
625							fullpath(dir), 2);
626					vallfn = NULL;
627					invlfn = NULL;
628				}
629				continue;
630			}
631
632			if (p[8] != ' ')
633				dirent.name[k++] = '.';
634			for (j = 0; j < 3; j++)
635				dirent.name[k++] = p[j+8];
636			dirent.name[k] = '\0';
637			for (k--; k >= 0 && dirent.name[k] == ' '; k--)
638				dirent.name[k] = '\0';
639
640			if (vallfn && shortSum != calcShortSum(p)) {
641				if (!invlfn) {
642					invlfn = vallfn;
643					invcl = valcl;
644				}
645				vallfn = NULL;
646			}
647			dirent.head = p[26] | (p[27] << 8);
648			if (boot->ClustMask == CLUST32_MASK)
649				dirent.head |= (p[20] << 16) | (p[21] << 24);
650			dirent.size = p[28] | (p[29] << 8) | (p[30] << 16) | (p[31] << 24);
651			if (vallfn) {
652				strlcpy(dirent.lname, longName,
653				    sizeof(dirent.lname));
654				longName[0] = '\0';
655				shortSum = -1;
656			}
657
658			dirent.parent = dir;
659			dirent.next = dir->child;
660
661			if (invlfn) {
662				mod |= k = removede(f, boot, fat,
663						    invlfn, vallfn ? vallfn : p,
664						    invcl, vallfn ? valcl : cl, cl,
665						    fullpath(&dirent), 0);
666				if (mod & FSFATAL)
667					return FSFATAL;
668				if (vallfn
669				    ? (valcl == cl && vallfn != buffer)
670				    : p != buffer)
671					if (k & FSDIRMOD)
672						mod |= THISMOD;
673			}
674
675			vallfn = NULL; /* not used any longer */
676			invlfn = NULL;
677
678			if (dirent.size == 0 && !(dirent.flags & ATTR_DIRECTORY)) {
679				if (dirent.head != 0) {
680					pwarn("%s has clusters, but size 0\n",
681					      fullpath(&dirent));
682					if (ask(1, "Drop allocated clusters")) {
683						p[26] = p[27] = 0;
684						if (boot->ClustMask == CLUST32_MASK)
685							p[20] = p[21] = 0;
686						clearchain(boot, fat, dirent.head);
687						dirent.head = 0;
688						mod |= THISMOD|FSDIRMOD|FSFATMOD;
689					} else
690						mod |= FSERROR;
691				}
692			} else if (dirent.head == 0
693				   && !strcmp(dirent.name, "..")
694				   && dir->parent			/* XXX */
695				   && !dir->parent->parent) {
696				/*
697				 *  Do nothing, the parent is the root
698				 */
699			} else if (dirent.head < CLUST_FIRST
700				   || dirent.head >= boot->NumClusters
701				   || fat[dirent.head].next == CLUST_FREE
702				   || (fat[dirent.head].next >= CLUST_RSRVD
703				       && fat[dirent.head].next < CLUST_EOFS)
704				   || fat[dirent.head].head != dirent.head) {
705				if (dirent.head == 0)
706					pwarn("%s has no clusters\n",
707					      fullpath(&dirent));
708				else if (dirent.head < CLUST_FIRST
709					 || dirent.head >= boot->NumClusters)
710					pwarn("%s starts with cluster out of range(%u)\n",
711					      fullpath(&dirent),
712					      dirent.head);
713				else if (fat[dirent.head].next == CLUST_FREE)
714					pwarn("%s starts with free cluster\n",
715					      fullpath(&dirent));
716				else if (fat[dirent.head].next >= CLUST_RSRVD)
717					pwarn("%s starts with cluster marked %s\n",
718					      fullpath(&dirent),
719					      rsrvdcltype(fat[dirent.head].next));
720				else
721					pwarn("%s doesn't start a cluster chain\n",
722					      fullpath(&dirent));
723				if (dirent.flags & ATTR_DIRECTORY) {
724					if (ask(0, "Remove")) {
725						*p = SLOT_DELETED;
726						mod |= THISMOD|FSDIRMOD;
727					} else
728						mod |= FSERROR;
729					continue;
730				} else {
731					if (ask(1, "Truncate")) {
732						p[28] = p[29] = p[30] = p[31] = 0;
733						p[26] = p[27] = 0;
734						if (boot->ClustMask == CLUST32_MASK)
735							p[20] = p[21] = 0;
736						dirent.size = 0;
737						mod |= THISMOD|FSDIRMOD;
738					} else
739						mod |= FSERROR;
740				}
741			}
742
743			if (dirent.head >= CLUST_FIRST && dirent.head < boot->NumClusters)
744				fat[dirent.head].flags |= FAT_USED;
745
746			if (dirent.flags & ATTR_DIRECTORY) {
747				/*
748				 * gather more info for directories
749				 */
750				struct dirTodoNode *n;
751
752				if (dirent.size) {
753					pwarn("Directory %s has size != 0\n",
754					      fullpath(&dirent));
755					if (ask(1, "Correct")) {
756						p[28] = p[29] = p[30] = p[31] = 0;
757						dirent.size = 0;
758						mod |= THISMOD|FSDIRMOD;
759					} else
760						mod |= FSERROR;
761				}
762				/*
763				 * handle `.' and `..' specially
764				 */
765				if (strcmp(dirent.name, ".") == 0) {
766					if (dirent.head != dir->head) {
767						pwarn("`.' entry in %s has incorrect start cluster\n",
768						      fullpath(dir));
769						if (ask(1, "Correct")) {
770							dirent.head = dir->head;
771							p[26] = (u_char)dirent.head;
772							p[27] = (u_char)(dirent.head >> 8);
773							if (boot->ClustMask == CLUST32_MASK) {
774								p[20] = (u_char)(dirent.head >> 16);
775								p[21] = (u_char)(dirent.head >> 24);
776							}
777							mod |= THISMOD|FSDIRMOD;
778						} else
779							mod |= FSERROR;
780					}
781					continue;
782				}
783				if (strcmp(dirent.name, "..") == 0) {
784					if (dir->parent) {		/* XXX */
785						if (!dir->parent->parent) {
786							if (dirent.head) {
787								pwarn("`..' entry in %s has non-zero start cluster\n",
788								      fullpath(dir));
789								if (ask(1, "Correct")) {
790									dirent.head = 0;
791									p[26] = p[27] = 0;
792									if (boot->ClustMask == CLUST32_MASK)
793										p[20] = p[21] = 0;
794									mod |= THISMOD|FSDIRMOD;
795								} else
796									mod |= FSERROR;
797							}
798						} else if (dirent.head != dir->parent->head) {
799							pwarn("`..' entry in %s has incorrect start cluster\n",
800							      fullpath(dir));
801							if (ask(1, "Correct")) {
802								dirent.head = dir->parent->head;
803								p[26] = (u_char)dirent.head;
804								p[27] = (u_char)(dirent.head >> 8);
805								if (boot->ClustMask == CLUST32_MASK) {
806									p[20] = (u_char)(dirent.head >> 16);
807									p[21] = (u_char)(dirent.head >> 24);
808								}
809								mod |= THISMOD|FSDIRMOD;
810							} else
811								mod |= FSERROR;
812						}
813					}
814					continue;
815				}
816
817				/* create directory tree node */
818				if (!(d = newDosDirEntry())) {
819					perror("No space for directory");
820					return FSFATAL;
821				}
822				memcpy(d, &dirent, sizeof(struct dosDirEntry));
823				/* link it into the tree */
824				dir->child = d;
825
826				/* Enter this directory into the todo list */
827				if (!(n = newDirTodo())) {
828					perror("No space for todo list");
829					return FSFATAL;
830				}
831				n->next = pendingDirectories;
832				n->dir = d;
833				pendingDirectories = n;
834			} else {
835				mod |= k = checksize(boot, fat, p, &dirent);
836				if (k & FSDIRMOD)
837					mod |= THISMOD;
838			}
839			boot->NumFiles++;
840		}
841
842		if (!(boot->flags & FAT32) && !dir->parent)
843			break;
844
845		if (mod & THISMOD) {
846			last *= 32;
847			if (lseek(f, off, SEEK_SET) != off
848			    || write(f, buffer, last) != last) {
849				perror("Unable to write directory");
850				return FSFATAL;
851			}
852			mod &= ~THISMOD;
853		}
854	} while ((cl = fat[cl].next) >= CLUST_FIRST && cl < boot->NumClusters);
855	if (invlfn || vallfn)
856		mod |= removede(f, boot, fat,
857				invlfn ? invlfn : vallfn, p,
858				invlfn ? invcl : valcl, -1, 0,
859				fullpath(dir), 1);
860
861	/* The root directory of non fat32 filesystems is in a special
862	 * area and may have been modified above without being written out.
863	 */
864	if ((mod & FSDIRMOD) && !(boot->flags & FAT32) && !dir->parent) {
865		last *= 32;
866		if (lseek(f, off, SEEK_SET) != off
867		    || write(f, buffer, last) != last) {
868			perror("Unable to write directory");
869			return FSFATAL;
870		}
871		mod &= ~THISMOD;
872	}
873	return mod & ~THISMOD;
874}
875
876int
877handleDirTree(int dosfs, struct bootblock *boot, struct fatEntry *fat)
878{
879	int mod;
880
881	mod = readDosDirSection(dosfs, boot, fat, rootDir);
882	if (mod & FSFATAL)
883		return FSFATAL;
884
885	/*
886	 * process the directory todo list
887	 */
888	while (pendingDirectories) {
889		struct dosDirEntry *dir = pendingDirectories->dir;
890		struct dirTodoNode *n = pendingDirectories->next;
891
892		/*
893		 * remove TODO entry now, the list might change during
894		 * directory reads
895		 */
896		freeDirTodo(pendingDirectories);
897		pendingDirectories = n;
898
899		/*
900		 * handle subdirectory
901		 */
902		mod |= readDosDirSection(dosfs, boot, fat, dir);
903		if (mod & FSFATAL)
904			return FSFATAL;
905	}
906
907	return mod;
908}
909
910/*
911 * Try to reconnect a FAT chain into dir
912 */
913static u_char *lfbuf;
914static cl_t lfcl;
915static off_t lfoff;
916
917int
918reconnect(int dosfs, struct bootblock *boot, struct fatEntry *fat, cl_t head)
919{
920	struct dosDirEntry d;
921	u_char *p;
922
923	if (!ask(1, "Reconnect"))
924		return FSERROR;
925
926	if (!lostDir) {
927		for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) {
928			if (!strcmp(lostDir->name, LOSTDIR))
929				break;
930		}
931		if (!lostDir) {		/* Create LOSTDIR?		XXX */
932			pwarn("No %s directory\n", LOSTDIR);
933			return FSERROR;
934		}
935	}
936	if (!lfbuf) {
937		lfbuf = malloc(boot->ClusterSize);
938		if (!lfbuf) {
939			perror("No space for buffer");
940			return FSFATAL;
941		}
942		p = NULL;
943	} else
944		p = lfbuf;
945	while (1) {
946		if (p)
947			for (; p < lfbuf + boot->ClusterSize; p += 32)
948				if (*p == SLOT_EMPTY
949				    || *p == SLOT_DELETED)
950					break;
951		if (p && p < lfbuf + boot->ClusterSize)
952			break;
953		lfcl = p ? fat[lfcl].next : lostDir->head;
954		if (lfcl < CLUST_FIRST || lfcl >= boot->NumClusters) {
955			/* Extend LOSTDIR?				XXX */
956			pwarn("No space in %s\n", LOSTDIR);
957			return FSERROR;
958		}
959		lfoff = lfcl * boot->ClusterSize
960		    + boot->ClusterOffset * boot->bpbBytesPerSec;
961		if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
962		    || (size_t)read(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
963			perror("could not read LOST.DIR");
964			return FSFATAL;
965		}
966		p = lfbuf;
967	}
968
969	boot->NumFiles++;
970	/* Ensure uniqueness of entry here!				XXX */
971	memset(&d, 0, sizeof d);
972	(void)snprintf(d.name, sizeof(d.name), "%u", head);
973	d.flags = 0;
974	d.head = head;
975	d.size = fat[head].length * boot->ClusterSize;
976
977	memset(p, 0, 32);
978	memset(p, ' ', 11);
979	memcpy(p, d.name, strlen(d.name));
980	p[26] = (u_char)d.head;
981	p[27] = (u_char)(d.head >> 8);
982	if (boot->ClustMask == CLUST32_MASK) {
983		p[20] = (u_char)(d.head >> 16);
984		p[21] = (u_char)(d.head >> 24);
985	}
986	p[28] = (u_char)d.size;
987	p[29] = (u_char)(d.size >> 8);
988	p[30] = (u_char)(d.size >> 16);
989	p[31] = (u_char)(d.size >> 24);
990	fat[head].flags |= FAT_USED;
991	if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
992	    || (size_t)write(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
993		perror("could not write LOST.DIR");
994		return FSFATAL;
995	}
996	return FSDIRMOD;
997}
998
999void
1000finishlf(void)
1001{
1002	if (lfbuf)
1003		free(lfbuf);
1004	lfbuf = NULL;
1005}
1006