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$";
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 ||
246		    boot->bpbRootClust >= boot->NumClusters) {
247			pfatal("Root directory starts with cluster out of range(%u)",
248			       boot->bpbRootClust);
249			return FSFATAL;
250		}
251		cl = fat[boot->bpbRootClust].next;
252		if (cl < CLUST_FIRST
253		    || (cl >= CLUST_RSRVD && cl< CLUST_EOFS)
254		    || fat[boot->bpbRootClust].head != boot->bpbRootClust) {
255			if (cl == CLUST_FREE)
256				pwarn("Root directory starts with free cluster\n");
257			else if (cl >= CLUST_RSRVD)
258				pwarn("Root directory starts with cluster marked %s\n",
259				      rsrvdcltype(cl));
260			else {
261				pfatal("Root directory doesn't start a cluster chain");
262				return FSFATAL;
263			}
264			if (ask(1, "Fix")) {
265				fat[boot->bpbRootClust].next = CLUST_FREE;
266				ret = FSFATMOD;
267			} else
268				ret = FSFATAL;
269		}
270
271		fat[boot->bpbRootClust].flags |= FAT_USED;
272		rootDir->head = boot->bpbRootClust;
273	}
274
275	return ret;
276}
277
278/*
279 * Cleanup after a directory scan
280 */
281void
282finishDosDirSection(void)
283{
284	struct dirTodoNode *p, *np;
285	struct dosDirEntry *d, *nd;
286
287	for (p = pendingDirectories; p; p = np) {
288		np = p->next;
289		freeDirTodo(p);
290	}
291	pendingDirectories = 0;
292	for (d = rootDir; d; d = nd) {
293		if ((nd = d->child) != NULL) {
294			d->child = 0;
295			continue;
296		}
297		if (!(nd = d->next))
298			nd = d->parent;
299		freeDosDirEntry(d);
300	}
301	rootDir = lostDir = NULL;
302	free(buffer);
303	free(delbuf);
304	buffer = NULL;
305	delbuf = NULL;
306}
307
308/*
309 * Delete directory entries between startcl, startoff and endcl, endoff.
310 */
311static int
312delete(int f, struct bootblock *boot, struct fatEntry *fat, cl_t startcl,
313    int startoff, cl_t endcl, int endoff, int notlast)
314{
315	u_char *s, *e;
316	off_t off;
317	int clsz = boot->bpbSecPerClust * boot->bpbBytesPerSec;
318
319	s = delbuf + startoff;
320	e = delbuf + clsz;
321	while (startcl >= CLUST_FIRST && startcl < boot->NumClusters) {
322		if (startcl == endcl) {
323			if (notlast)
324				break;
325			e = delbuf + endoff;
326		}
327		off = startcl * boot->bpbSecPerClust + boot->ClusterOffset;
328		off *= boot->bpbBytesPerSec;
329		if (lseek(f, off, SEEK_SET) != off
330		    || read(f, delbuf, clsz) != clsz) {
331			perror("Unable to read directory");
332			return FSFATAL;
333		}
334		while (s < e) {
335			*s = SLOT_DELETED;
336			s += 32;
337		}
338		if (lseek(f, off, SEEK_SET) != off
339		    || write(f, delbuf, clsz) != clsz) {
340			perror("Unable to write directory");
341			return FSFATAL;
342		}
343		if (startcl == endcl)
344			break;
345		startcl = fat[startcl].next;
346		s = delbuf;
347	}
348	return FSOK;
349}
350
351static int
352removede(int f, struct bootblock *boot, struct fatEntry *fat, u_char *start,
353    u_char *end, cl_t startcl, cl_t endcl, cl_t curcl, char *path, int type)
354{
355	switch (type) {
356	case 0:
357		pwarn("Invalid long filename entry for %s\n", path);
358		break;
359	case 1:
360		pwarn("Invalid long filename entry at end of directory %s\n",
361		    path);
362		break;
363	case 2:
364		pwarn("Invalid long filename entry for volume label\n");
365		break;
366	}
367	if (ask(0, "Remove")) {
368		if (startcl != curcl) {
369			if (delete(f, boot, fat,
370				   startcl, start - buffer,
371				   endcl, end - buffer,
372				   endcl == curcl) == FSFATAL)
373				return FSFATAL;
374			start = buffer;
375		}
376		/* startcl is < CLUST_FIRST for !fat32 root */
377		if ((endcl == curcl) || (startcl < CLUST_FIRST))
378			for (; start < end; start += 32)
379				*start = SLOT_DELETED;
380		return FSDIRMOD;
381	}
382	return FSERROR;
383}
384
385/*
386 * Check an in-memory file entry
387 */
388static int
389checksize(struct bootblock *boot, struct fatEntry *fat, u_char *p,
390    struct dosDirEntry *dir)
391{
392	/*
393	 * Check size on ordinary files
394	 */
395	u_int32_t physicalSize;
396
397	if (dir->head == CLUST_FREE)
398		physicalSize = 0;
399	else {
400		if (dir->head < CLUST_FIRST || dir->head >= boot->NumClusters)
401			return FSERROR;
402		physicalSize = fat[dir->head].length * boot->ClusterSize;
403	}
404	if (physicalSize < dir->size) {
405		pwarn("size of %s is %u, should at most be %u\n",
406		      fullpath(dir), dir->size, physicalSize);
407		if (ask(1, "Truncate")) {
408			dir->size = physicalSize;
409			p[28] = (u_char)physicalSize;
410			p[29] = (u_char)(physicalSize >> 8);
411			p[30] = (u_char)(physicalSize >> 16);
412			p[31] = (u_char)(physicalSize >> 24);
413			return FSDIRMOD;
414		} else
415			return FSERROR;
416	} else if (physicalSize - dir->size >= boot->ClusterSize) {
417		pwarn("%s has too many clusters allocated\n",
418		      fullpath(dir));
419		if (ask(1, "Drop superfluous clusters")) {
420			cl_t cl;
421			u_int32_t sz = 0;
422
423			for (cl = dir->head; (sz += boot->ClusterSize) <
424			    dir->size;)
425				cl = fat[cl].next;
426			clearchain(boot, fat, fat[cl].next);
427			fat[cl].next = CLUST_EOF;
428			return FSFATMOD;
429		} else
430			return FSERROR;
431	}
432	return FSOK;
433}
434
435/*
436 * Read a directory and
437 *   - resolve long name records
438 *   - enter file and directory records into the parent's list
439 *   - push directories onto the todo-stack
440 */
441static int
442readDosDirSection(int f, struct bootblock *boot, struct fatEntry *fat,
443    struct dosDirEntry *dir)
444{
445	struct dosDirEntry dirent, *d;
446	u_char *p, *vallfn, *invlfn, *empty;
447	off_t off;
448	int i, j, k, last;
449	cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0;
450	char *t;
451	u_int lidx = 0;
452	int shortSum;
453	int mod = FSOK;
454#define	THISMOD	0x8000			/* Only used within this routine */
455
456	cl = dir->head;
457	if (dir->parent && (cl < CLUST_FIRST || cl >= boot->NumClusters)) {
458		/*
459		 * Already handled somewhere else.
460		 */
461		return FSOK;
462	}
463	shortSum = -1;
464	vallfn = invlfn = empty = NULL;
465	do {
466		if (!(boot->flags & FAT32) && !dir->parent) {
467			last = boot->bpbRootDirEnts * 32;
468			off = boot->bpbResSectors + boot->bpbFATs *
469			    boot->FATsecs;
470		} else {
471			last = boot->bpbSecPerClust * boot->bpbBytesPerSec;
472			off = cl * boot->bpbSecPerClust + boot->ClusterOffset;
473		}
474
475		off *= boot->bpbBytesPerSec;
476		if (lseek(f, off, SEEK_SET) != off
477		    || read(f, buffer, last) != last) {
478			perror("Unable to read directory");
479			return FSFATAL;
480		}
481		last /= 32;
482		/*
483		 * Check `.' and `..' entries here?			XXX
484		 */
485		for (p = buffer, i = 0; i < last; i++, p += 32) {
486			if (dir->fsckflags & DIREMPWARN) {
487				*p = SLOT_EMPTY;
488				continue;
489			}
490
491			if (*p == SLOT_EMPTY || *p == SLOT_DELETED) {
492				if (*p == SLOT_EMPTY) {
493					dir->fsckflags |= DIREMPTY;
494					empty = p;
495					empcl = cl;
496				}
497				continue;
498			}
499
500			if (dir->fsckflags & DIREMPTY) {
501				if (!(dir->fsckflags & DIREMPWARN)) {
502					pwarn("%s has entries after end of directory\n",
503					      fullpath(dir));
504					if (ask(1, "Extend")) {
505						u_char *q;
506
507						dir->fsckflags &= ~DIREMPTY;
508						if (delete(f, boot, fat,
509							   empcl, empty - buffer,
510							   cl, p - buffer, 1) == FSFATAL)
511							return FSFATAL;
512						q = empcl == cl ? empty : buffer;
513						for (; q < p; q += 32)
514							*q = SLOT_DELETED;
515						mod |= THISMOD|FSDIRMOD;
516					} else if (ask(0, "Truncate"))
517						dir->fsckflags |= DIREMPWARN;
518				}
519				if (dir->fsckflags & DIREMPWARN) {
520					*p = SLOT_DELETED;
521					mod |= THISMOD|FSDIRMOD;
522					continue;
523				} else if (dir->fsckflags & DIREMPTY)
524					mod |= FSERROR;
525				empty = NULL;
526			}
527
528			if (p[11] == ATTR_WIN95) {
529				if (*p & LRFIRST) {
530					if (shortSum != -1) {
531						if (!invlfn) {
532							invlfn = vallfn;
533							invcl = valcl;
534						}
535					}
536					memset(longName, 0, sizeof longName);
537					shortSum = p[13];
538					vallfn = p;
539					valcl = cl;
540				} else if (shortSum != p[13]
541					   || lidx != (*p & LRNOMASK)) {
542					if (!invlfn) {
543						invlfn = vallfn;
544						invcl = valcl;
545					}
546					if (!invlfn) {
547						invlfn = p;
548						invcl = cl;
549					}
550					vallfn = NULL;
551				}
552				lidx = *p & LRNOMASK;
553				t = longName + --lidx * 13;
554				for (k = 1; k < 11 && t < longName +
555				    sizeof(longName); k += 2) {
556					if (!p[k] && !p[k + 1])
557						break;
558					*t++ = p[k];
559					/*
560					 * Warn about those unusable chars in msdosfs here?	XXX
561					 */
562					if (p[k + 1])
563						t[-1] = '?';
564				}
565				if (k >= 11)
566					for (k = 14; k < 26 && t < longName + sizeof(longName); k += 2) {
567						if (!p[k] && !p[k + 1])
568							break;
569						*t++ = p[k];
570						if (p[k + 1])
571							t[-1] = '?';
572					}
573				if (k >= 26)
574					for (k = 28; k < 32 && t < longName + sizeof(longName); k += 2) {
575						if (!p[k] && !p[k + 1])
576							break;
577						*t++ = p[k];
578						if (p[k + 1])
579							t[-1] = '?';
580					}
581				if (t >= longName + sizeof(longName)) {
582					pwarn("long filename too long\n");
583					if (!invlfn) {
584						invlfn = vallfn;
585						invcl = valcl;
586					}
587					vallfn = NULL;
588				}
589				if (p[26] | (p[27] << 8)) {
590					pwarn("long filename record cluster start != 0\n");
591					if (!invlfn) {
592						invlfn = vallfn;
593						invcl = cl;
594					}
595					vallfn = NULL;
596				}
597				continue;	/* long records don't carry further
598						 * information */
599			}
600
601			/*
602			 * This is a standard msdosfs directory entry.
603			 */
604			memset(&dirent, 0, sizeof dirent);
605
606			/*
607			 * it's a short name record, but we need to know
608			 * more, so get the flags first.
609			 */
610			dirent.flags = p[11];
611
612			/*
613			 * Translate from 850 to ISO here		XXX
614			 */
615			for (j = 0; j < 8; j++)
616				dirent.name[j] = p[j];
617			dirent.name[8] = '\0';
618			for (k = 7; k >= 0 && dirent.name[k] == ' '; k--)
619				dirent.name[k] = '\0';
620			if (dirent.name[k] != '\0')
621				k++;
622			if (dirent.name[0] == SLOT_E5)
623				dirent.name[0] = 0xe5;
624
625			if (dirent.flags & ATTR_VOLUME) {
626				if (vallfn || invlfn) {
627					mod |= removede(f, boot, fat,
628							invlfn ? invlfn : vallfn, p,
629							invlfn ? invcl : valcl, -1, 0,
630							fullpath(dir), 2);
631					vallfn = NULL;
632					invlfn = NULL;
633				}
634				continue;
635			}
636
637			if (p[8] != ' ')
638				dirent.name[k++] = '.';
639			for (j = 0; j < 3; j++)
640				dirent.name[k++] = p[j+8];
641			dirent.name[k] = '\0';
642			for (k--; k >= 0 && dirent.name[k] == ' '; k--)
643				dirent.name[k] = '\0';
644
645			if (vallfn && shortSum != calcShortSum(p)) {
646				if (!invlfn) {
647					invlfn = vallfn;
648					invcl = valcl;
649				}
650				vallfn = NULL;
651			}
652			dirent.head = p[26] | (p[27] << 8);
653			if (boot->ClustMask == CLUST32_MASK)
654				dirent.head |= (p[20] << 16) | (p[21] << 24);
655			dirent.size = p[28] | (p[29] << 8) | (p[30] << 16) | (p[31] << 24);
656			if (vallfn) {
657				strlcpy(dirent.lname, longName,
658				    sizeof(dirent.lname));
659				longName[0] = '\0';
660				shortSum = -1;
661			}
662
663			dirent.parent = dir;
664			dirent.next = dir->child;
665
666			if (invlfn) {
667				mod |= k = removede(f, boot, fat,
668						    invlfn, vallfn ? vallfn : p,
669						    invcl, vallfn ? valcl : cl, cl,
670						    fullpath(&dirent), 0);
671				if (mod & FSFATAL)
672					return FSFATAL;
673				if (vallfn
674				    ? (valcl == cl && vallfn != buffer)
675				    : p != buffer)
676					if (k & FSDIRMOD)
677						mod |= THISMOD;
678			}
679
680			vallfn = NULL; /* not used any longer */
681			invlfn = NULL;
682
683			if (dirent.size == 0 && !(dirent.flags & ATTR_DIRECTORY)) {
684				if (dirent.head != 0) {
685					pwarn("%s has clusters, but size 0\n",
686					      fullpath(&dirent));
687					if (ask(1, "Drop allocated clusters")) {
688						p[26] = p[27] = 0;
689						if (boot->ClustMask == CLUST32_MASK)
690							p[20] = p[21] = 0;
691						clearchain(boot, fat, dirent.head);
692						dirent.head = 0;
693						mod |= THISMOD|FSDIRMOD|FSFATMOD;
694					} else
695						mod |= FSERROR;
696				}
697			} else if (dirent.head == 0
698				   && !strcmp(dirent.name, "..")
699				   && dir->parent			/* XXX */
700				   && !dir->parent->parent) {
701				/*
702				 *  Do nothing, the parent is the root
703				 */
704			} else if (dirent.head < CLUST_FIRST
705				   || dirent.head >= boot->NumClusters
706				   || fat[dirent.head].next == CLUST_FREE
707				   || (fat[dirent.head].next >= CLUST_RSRVD
708				       && fat[dirent.head].next < CLUST_EOFS)
709				   || fat[dirent.head].head != dirent.head) {
710				if (dirent.head == 0)
711					pwarn("%s has no clusters\n",
712					      fullpath(&dirent));
713				else if (dirent.head < CLUST_FIRST
714					 || dirent.head >= boot->NumClusters)
715					pwarn("%s starts with cluster out of range(%u)\n",
716					      fullpath(&dirent),
717					      dirent.head);
718				else if (fat[dirent.head].next == CLUST_FREE)
719					pwarn("%s starts with free cluster\n",
720					      fullpath(&dirent));
721				else if (fat[dirent.head].next >= CLUST_RSRVD)
722					pwarn("%s starts with cluster marked %s\n",
723					      fullpath(&dirent),
724					      rsrvdcltype(fat[dirent.head].next));
725				else
726					pwarn("%s doesn't start a cluster chain\n",
727					      fullpath(&dirent));
728				if (dirent.flags & ATTR_DIRECTORY) {
729					if (ask(0, "Remove")) {
730						*p = SLOT_DELETED;
731						mod |= THISMOD|FSDIRMOD;
732					} else
733						mod |= FSERROR;
734					continue;
735				} else {
736					if (ask(1, "Truncate")) {
737						p[28] = p[29] = p[30] = p[31] = 0;
738						p[26] = p[27] = 0;
739						if (boot->ClustMask == CLUST32_MASK)
740							p[20] = p[21] = 0;
741						dirent.size = 0;
742						mod |= THISMOD|FSDIRMOD;
743					} else
744						mod |= FSERROR;
745				}
746			}
747
748			if (dirent.head >= CLUST_FIRST && dirent.head < boot->NumClusters)
749				fat[dirent.head].flags |= FAT_USED;
750
751			if (dirent.flags & ATTR_DIRECTORY) {
752				/*
753				 * gather more info for directories
754				 */
755				struct dirTodoNode *n;
756
757				if (dirent.size) {
758					pwarn("Directory %s has size != 0\n",
759					      fullpath(&dirent));
760					if (ask(1, "Correct")) {
761						p[28] = p[29] = p[30] = p[31] = 0;
762						dirent.size = 0;
763						mod |= THISMOD|FSDIRMOD;
764					} else
765						mod |= FSERROR;
766				}
767				/*
768				 * handle `.' and `..' specially
769				 */
770				if (strcmp(dirent.name, ".") == 0) {
771					if (dirent.head != dir->head) {
772						pwarn("`.' entry in %s has incorrect start cluster\n",
773						      fullpath(dir));
774						if (ask(1, "Correct")) {
775							dirent.head = dir->head;
776							p[26] = (u_char)dirent.head;
777							p[27] = (u_char)(dirent.head >> 8);
778							if (boot->ClustMask == CLUST32_MASK) {
779								p[20] = (u_char)(dirent.head >> 16);
780								p[21] = (u_char)(dirent.head >> 24);
781							}
782							mod |= THISMOD|FSDIRMOD;
783						} else
784							mod |= FSERROR;
785					}
786					continue;
787				}
788				if (strcmp(dirent.name, "..") == 0) {
789					if (dir->parent) {		/* XXX */
790						if (!dir->parent->parent) {
791							if (dirent.head) {
792								pwarn("`..' entry in %s has non-zero start cluster\n",
793								      fullpath(dir));
794								if (ask(1, "Correct")) {
795									dirent.head = 0;
796									p[26] = p[27] = 0;
797									if (boot->ClustMask == CLUST32_MASK)
798										p[20] = p[21] = 0;
799									mod |= THISMOD|FSDIRMOD;
800								} else
801									mod |= FSERROR;
802							}
803						} else if (dirent.head != dir->parent->head) {
804							pwarn("`..' entry in %s has incorrect start cluster\n",
805							      fullpath(dir));
806							if (ask(1, "Correct")) {
807								dirent.head = dir->parent->head;
808								p[26] = (u_char)dirent.head;
809								p[27] = (u_char)(dirent.head >> 8);
810								if (boot->ClustMask == CLUST32_MASK) {
811									p[20] = (u_char)(dirent.head >> 16);
812									p[21] = (u_char)(dirent.head >> 24);
813								}
814								mod |= THISMOD|FSDIRMOD;
815							} else
816								mod |= FSERROR;
817						}
818					}
819					continue;
820				}
821
822				/* create directory tree node */
823				if (!(d = newDosDirEntry())) {
824					perror("No space for directory");
825					return FSFATAL;
826				}
827				memcpy(d, &dirent, sizeof(struct dosDirEntry));
828				/* link it into the tree */
829				dir->child = d;
830
831				/* Enter this directory into the todo list */
832				if (!(n = newDirTodo())) {
833					perror("No space for todo list");
834					return FSFATAL;
835				}
836				n->next = pendingDirectories;
837				n->dir = d;
838				pendingDirectories = n;
839			} else {
840				mod |= k = checksize(boot, fat, p, &dirent);
841				if (k & FSDIRMOD)
842					mod |= THISMOD;
843			}
844			boot->NumFiles++;
845		}
846
847		if (!(boot->flags & FAT32) && !dir->parent)
848			break;
849
850		if (mod & THISMOD) {
851			last *= 32;
852			if (lseek(f, off, SEEK_SET) != off
853			    || write(f, buffer, last) != last) {
854				perror("Unable to write directory");
855				return FSFATAL;
856			}
857			mod &= ~THISMOD;
858		}
859	} while ((cl = fat[cl].next) >= CLUST_FIRST && cl < boot->NumClusters);
860	if (invlfn || vallfn)
861		mod |= removede(f, boot, fat,
862				invlfn ? invlfn : vallfn, p,
863				invlfn ? invcl : valcl, -1, 0,
864				fullpath(dir), 1);
865
866	/* The root directory of non fat32 filesystems is in a special
867	 * area and may have been modified above without being written out.
868	 */
869	if ((mod & FSDIRMOD) && !(boot->flags & FAT32) && !dir->parent) {
870		last *= 32;
871		if (lseek(f, off, SEEK_SET) != off
872		    || write(f, buffer, last) != last) {
873			perror("Unable to write directory");
874			return FSFATAL;
875		}
876		mod &= ~THISMOD;
877	}
878	return mod & ~THISMOD;
879}
880
881int
882handleDirTree(int dosfs, struct bootblock *boot, struct fatEntry *fat)
883{
884	int mod;
885
886	mod = readDosDirSection(dosfs, boot, fat, rootDir);
887	if (mod & FSFATAL)
888		return FSFATAL;
889
890	/*
891	 * process the directory todo list
892	 */
893	while (pendingDirectories) {
894		struct dosDirEntry *dir = pendingDirectories->dir;
895		struct dirTodoNode *n = pendingDirectories->next;
896
897		/*
898		 * remove TODO entry now, the list might change during
899		 * directory reads
900		 */
901		freeDirTodo(pendingDirectories);
902		pendingDirectories = n;
903
904		/*
905		 * handle subdirectory
906		 */
907		mod |= readDosDirSection(dosfs, boot, fat, dir);
908		if (mod & FSFATAL)
909			return FSFATAL;
910	}
911
912	return mod;
913}
914
915/*
916 * Try to reconnect a FAT chain into dir
917 */
918static u_char *lfbuf;
919static cl_t lfcl;
920static off_t lfoff;
921
922int
923reconnect(int dosfs, struct bootblock *boot, struct fatEntry *fat, cl_t head)
924{
925	struct dosDirEntry d;
926	u_char *p;
927
928	if (!ask(1, "Reconnect"))
929		return FSERROR;
930
931	if (!lostDir) {
932		for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) {
933			if (!strcmp(lostDir->name, LOSTDIR))
934				break;
935		}
936		if (!lostDir) {		/* Create LOSTDIR?		XXX */
937			pwarn("No %s directory\n", LOSTDIR);
938			return FSERROR;
939		}
940	}
941	if (!lfbuf) {
942		lfbuf = malloc(boot->ClusterSize);
943		if (!lfbuf) {
944			perror("No space for buffer");
945			return FSFATAL;
946		}
947		p = NULL;
948	} else
949		p = lfbuf;
950	while (1) {
951		if (p)
952			for (; p < lfbuf + boot->ClusterSize; p += 32)
953				if (*p == SLOT_EMPTY
954				    || *p == SLOT_DELETED)
955					break;
956		if (p && p < lfbuf + boot->ClusterSize)
957			break;
958		lfcl = p ? fat[lfcl].next : lostDir->head;
959		if (lfcl < CLUST_FIRST || lfcl >= boot->NumClusters) {
960			/* Extend LOSTDIR?				XXX */
961			pwarn("No space in %s\n", LOSTDIR);
962			return FSERROR;
963		}
964		lfoff = lfcl * boot->ClusterSize
965		    + boot->ClusterOffset * boot->bpbBytesPerSec;
966		if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
967		    || (size_t)read(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
968			perror("could not read LOST.DIR");
969			return FSFATAL;
970		}
971		p = lfbuf;
972	}
973
974	boot->NumFiles++;
975	/* Ensure uniqueness of entry here!				XXX */
976	memset(&d, 0, sizeof d);
977	(void)snprintf(d.name, sizeof(d.name), "%u", head);
978	d.flags = 0;
979	d.head = head;
980	d.size = fat[head].length * boot->ClusterSize;
981
982	memset(p, 0, 32);
983	memset(p, ' ', 11);
984	memcpy(p, d.name, strlen(d.name));
985	p[26] = (u_char)d.head;
986	p[27] = (u_char)(d.head >> 8);
987	if (boot->ClustMask == CLUST32_MASK) {
988		p[20] = (u_char)(d.head >> 16);
989		p[21] = (u_char)(d.head >> 24);
990	}
991	p[28] = (u_char)d.size;
992	p[29] = (u_char)(d.size >> 8);
993	p[30] = (u_char)(d.size >> 16);
994	p[31] = (u_char)(d.size >> 24);
995	fat[head].flags |= FAT_USED;
996	if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
997	    || (size_t)write(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
998		perror("could not write LOST.DIR");
999		return FSFATAL;
1000	}
1001	return FSDIRMOD;
1002}
1003
1004void
1005finishlf(void)
1006{
1007	if (lfbuf)
1008		free(lfbuf);
1009	lfbuf = NULL;
1010}
1011