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.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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.
29 #include <sys/cdefs.h>
31 __RCSID("$NetBSD: dir.c,v 1.14 1998/08/25 19:18:15 ross Exp $");
32 static const char rcsid[] =
43 #include <sys/param.h>
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 */
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 */
60 #define ATTR_WIN95 0x0f /* long name record */
63 * This is the format of the contents of the deTime field in the direntry
65 * We don't use bitfields because we don't know how compilers for
66 * arbitrary machines will lay them out.
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
76 * This is the format of the contents of the deDate field in the direntry
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
88 static struct dosDirEntry *newDosDirEntry(void);
89 static void freeDosDirEntry(struct dosDirEntry *);
90 static struct dirTodoNode *newDirTodo(void);
91 static void freeDirTodo(struct dirTodoNode *);
92 static char *fullpath(struct dosDirEntry *);
93 static u_char calcShortSum(u_char *);
94 static int delete(int, struct bootblock *, struct fatEntry *, cl_t, int,
96 static int removede(int, struct bootblock *, struct fatEntry *, u_char *,
97 u_char *, cl_t, cl_t, cl_t, char *, int);
98 static int checksize(struct bootblock *, struct fatEntry *, u_char *,
99 struct dosDirEntry *);
100 static int readDosDirSection(int, struct bootblock *, struct fatEntry *,
101 struct dosDirEntry *);
104 * Manage free dosDirEntry structures.
106 static struct dosDirEntry *freede;
108 static struct dosDirEntry *
111 struct dosDirEntry *de;
113 if (!(de = freede)) {
114 if (!(de = (struct dosDirEntry *)malloc(sizeof *de)))
122 freeDosDirEntry(struct dosDirEntry *de)
129 * The same for dirTodoNode structures.
131 static struct dirTodoNode *freedt;
133 static struct dirTodoNode *
136 struct dirTodoNode *dt;
138 if (!(dt = freedt)) {
139 if (!(dt = (struct dirTodoNode *)malloc(sizeof *dt)))
147 freeDirTodo(struct dirTodoNode *dt)
154 * The stack of unread directories
156 struct dirTodoNode *pendingDirectories = NULL;
159 * Return the full pathname for a directory entry.
162 fullpath(struct dosDirEntry *dir)
164 static char namebuf[MAXPATHLEN + 1];
168 cp = namebuf + sizeof namebuf - 1;
171 np = dir->lname[0] ? dir->lname : dir->name;
173 if ((cp -= nl) <= namebuf + 1)
177 } while ((dir = dir->parent) != NULL);
186 * Calculate a checksum over an 8.3 alias name
189 calcShortSum(u_char *p)
194 for (i = 0; i < 11; i++) {
195 sum = (sum << 7)|(sum >> 1); /* rotate right */
203 * Global variables temporarily used during a directory scan
205 static char longName[DOSLONGNAMELEN] = "";
206 static u_char *buffer = NULL;
207 static u_char *delbuf = NULL;
209 static struct dosDirEntry *rootDir;
210 static struct dosDirEntry *lostDir;
213 * Init internal state for a new directory scan.
216 resetDosDirSection(struct bootblock *boot, struct fatEntry *fat)
222 b1 = boot->bpbRootDirEnts * 32;
223 b2 = boot->bpbSecPerClust * boot->bpbBytesPerSec;
225 if ((buffer = malloc( b1 > b2 ? b1 : b2)) == NULL) {
226 perror("No space for directory buffer");
230 if ((delbuf = malloc(b2)) == NULL) {
232 perror("No space for directory delbuf");
236 if ((rootDir = newDosDirEntry()) == NULL) {
239 perror("No space for directory entry");
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)",
251 cl = fat[boot->bpbRootClust].next;
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",
261 pfatal("Root directory doesn't start a cluster chain");
265 fat[boot->bpbRootClust].next = CLUST_FREE;
271 fat[boot->bpbRootClust].flags |= FAT_USED;
272 rootDir->head = boot->bpbRootClust;
279 * Cleanup after a directory scan
282 finishDosDirSection(void)
284 struct dirTodoNode *p, *np;
285 struct dosDirEntry *d, *nd;
287 for (p = pendingDirectories; p; p = np) {
291 pendingDirectories = 0;
292 for (d = rootDir; d; d = nd) {
293 if ((nd = d->child) != NULL) {
301 rootDir = lostDir = NULL;
309 * Delete directory entries between startcl, startoff and endcl, endoff.
312 delete(int f, struct bootblock *boot, struct fatEntry *fat, cl_t startcl,
313 int startoff, cl_t endcl, int endoff, int notlast)
317 int clsz = boot->bpbSecPerClust * boot->bpbBytesPerSec;
319 s = delbuf + startoff;
321 while (startcl >= CLUST_FIRST && startcl < boot->NumClusters) {
322 if (startcl == endcl) {
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");
338 if (lseek(f, off, SEEK_SET) != off
339 || write(f, delbuf, clsz) != clsz) {
340 perror("Unable to write directory");
343 if (startcl == endcl)
345 startcl = fat[startcl].next;
352 removede(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)
357 pwarn("Invalid long filename entry for %s\n", path);
360 pwarn("Invalid long filename entry at end of directory %s\n",
364 pwarn("Invalid long filename entry for volume label\n");
367 if (ask(0, "Remove")) {
368 if (startcl != curcl) {
369 if (delete(f, boot, fat,
370 startcl, start - buffer,
372 endcl == curcl) == FSFATAL)
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;
386 * Check an in-memory file entry
389 checksize(struct bootblock *boot, struct fatEntry *fat, u_char *p,
390 struct dosDirEntry *dir)
393 * Check size on ordinary files
395 u_int32_t physicalSize;
397 if (dir->head == CLUST_FREE)
400 if (dir->head < CLUST_FIRST || dir->head >= boot->NumClusters)
402 physicalSize = fat[dir->head].length * boot->ClusterSize;
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);
416 } else if (physicalSize - dir->size >= boot->ClusterSize) {
417 pwarn("%s has too many clusters allocated\n",
419 if (ask(1, "Drop superfluous clusters")) {
423 for (cl = dir->head; (sz += boot->ClusterSize) <
426 clearchain(boot, fat, fat[cl].next);
427 fat[cl].next = CLUST_EOF;
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
442 readDosDirSection(int f, struct bootblock *boot, struct fatEntry *fat,
443 struct dosDirEntry *dir)
445 struct dosDirEntry dirent, *d;
446 u_char *p, *vallfn, *invlfn, *empty;
449 cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0;
454 #define THISMOD 0x8000 /* Only used within this routine */
457 if (dir->parent && (cl < CLUST_FIRST || cl >= boot->NumClusters)) {
459 * Already handled somewhere else.
464 vallfn = invlfn = empty = NULL;
466 if (!(boot->flags & FAT32) && !dir->parent) {
467 last = boot->bpbRootDirEnts * 32;
468 off = boot->bpbResSectors + boot->bpbFATs *
471 last = boot->bpbSecPerClust * boot->bpbBytesPerSec;
472 off = cl * boot->bpbSecPerClust + boot->ClusterOffset;
475 off *= boot->bpbBytesPerSec;
476 if (lseek(f, off, SEEK_SET) != off
477 || read(f, buffer, last) != last) {
478 perror("Unable to read directory");
483 * Check `.' and `..' entries here? XXX
485 for (p = buffer, i = 0; i < last; i++, p += 32) {
486 if (dir->fsckflags & DIREMPWARN) {
491 if (*p == SLOT_EMPTY || *p == SLOT_DELETED) {
492 if (*p == SLOT_EMPTY) {
493 dir->fsckflags |= DIREMPTY;
500 if (dir->fsckflags & DIREMPTY) {
501 if (!(dir->fsckflags & DIREMPWARN)) {
502 pwarn("%s has entries after end of directory\n",
504 if (ask(1, "Extend")) {
507 dir->fsckflags &= ~DIREMPTY;
508 if (delete(f, boot, fat,
509 empcl, empty - buffer,
510 cl, p - buffer, 1) == FSFATAL)
512 q = empcl == cl ? empty : buffer;
513 for (; q < p; q += 32)
515 mod |= THISMOD|FSDIRMOD;
516 } else if (ask(0, "Truncate"))
517 dir->fsckflags |= DIREMPWARN;
519 if (dir->fsckflags & DIREMPWARN) {
521 mod |= THISMOD|FSDIRMOD;
523 } else if (dir->fsckflags & DIREMPTY)
528 if (p[11] == ATTR_WIN95) {
530 if (shortSum != -1) {
536 memset(longName, 0, sizeof longName);
540 } else if (shortSum != p[13]
541 || lidx != (*p & LRNOMASK)) {
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])
560 * Warn about those unusable chars in msdosfs here? XXX
566 for (k = 14; k < 26 && t < longName + sizeof(longName); k += 2) {
567 if (!p[k] && !p[k + 1])
574 for (k = 28; k < 32 && t < longName + sizeof(longName); k += 2) {
575 if (!p[k] && !p[k + 1])
581 if (t >= longName + sizeof(longName)) {
582 pwarn("long filename too long\n");
589 if (p[26] | (p[27] << 8)) {
590 pwarn("long filename record cluster start != 0\n");
597 continue; /* long records don't carry further
602 * This is a standard msdosfs directory entry.
604 memset(&dirent, 0, sizeof dirent);
607 * it's a short name record, but we need to know
608 * more, so get the flags first.
610 dirent.flags = p[11];
613 * Translate from 850 to ISO here XXX
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')
622 if (dirent.name[0] == SLOT_E5)
623 dirent.name[0] = 0xe5;
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,
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';
645 if (vallfn && shortSum != calcShortSum(p)) {
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);
657 strlcpy(dirent.lname, longName,
658 sizeof(dirent.lname));
664 dirent.next = dir->child;
667 mod |= k = removede(f, boot, fat,
668 invlfn, vallfn ? vallfn : p,
669 invcl, vallfn ? valcl : cl, cl,
670 fullpath(&dirent), 0);
674 ? (valcl == cl && vallfn != buffer)
680 vallfn = NULL; /* not used any longer */
683 if (dirent.size == 0 && !(dirent.flags & ATTR_DIRECTORY)) {
684 if (dirent.head != 0) {
685 pwarn("%s has clusters, but size 0\n",
687 if (ask(1, "Drop allocated clusters")) {
689 if (boot->ClustMask == CLUST32_MASK)
691 clearchain(boot, fat, dirent.head);
693 mod |= THISMOD|FSDIRMOD|FSFATMOD;
697 } else if (dirent.head == 0
698 && !strcmp(dirent.name, "..")
699 && dir->parent /* XXX */
700 && !dir->parent->parent) {
702 * Do nothing, the parent is the root
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",
713 else if (dirent.head < CLUST_FIRST
714 || dirent.head >= boot->NumClusters)
715 pwarn("%s starts with cluster out of range(%u)\n",
718 else if (fat[dirent.head].next == CLUST_FREE)
719 pwarn("%s starts with free cluster\n",
721 else if (fat[dirent.head].next >= CLUST_RSRVD)
722 pwarn("%s starts with cluster marked %s\n",
724 rsrvdcltype(fat[dirent.head].next));
726 pwarn("%s doesn't start a cluster chain\n",
728 if (dirent.flags & ATTR_DIRECTORY) {
729 if (ask(0, "Remove")) {
731 mod |= THISMOD|FSDIRMOD;
736 if (ask(1, "Truncate")) {
737 p[28] = p[29] = p[30] = p[31] = 0;
739 if (boot->ClustMask == CLUST32_MASK)
742 mod |= THISMOD|FSDIRMOD;
748 if (dirent.head >= CLUST_FIRST && dirent.head < boot->NumClusters)
749 fat[dirent.head].flags |= FAT_USED;
751 if (dirent.flags & ATTR_DIRECTORY) {
753 * gather more info for directories
755 struct dirTodoNode *n;
758 pwarn("Directory %s has size != 0\n",
760 if (ask(1, "Correct")) {
761 p[28] = p[29] = p[30] = p[31] = 0;
763 mod |= THISMOD|FSDIRMOD;
768 * handle `.' and `..' specially
770 if (strcmp(dirent.name, ".") == 0) {
771 if (dirent.head != dir->head) {
772 pwarn("`.' entry in %s has incorrect start cluster\n",
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);
782 mod |= THISMOD|FSDIRMOD;
788 if (strcmp(dirent.name, "..") == 0) {
789 if (dir->parent) { /* XXX */
790 if (!dir->parent->parent) {
792 pwarn("`..' entry in %s has non-zero start cluster\n",
794 if (ask(1, "Correct")) {
797 if (boot->ClustMask == CLUST32_MASK)
799 mod |= THISMOD|FSDIRMOD;
803 } else if (dirent.head != dir->parent->head) {
804 pwarn("`..' entry in %s has incorrect start cluster\n",
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);
814 mod |= THISMOD|FSDIRMOD;
822 /* create directory tree node */
823 if (!(d = newDosDirEntry())) {
824 perror("No space for directory");
827 memcpy(d, &dirent, sizeof(struct dosDirEntry));
828 /* link it into the tree */
831 /* Enter this directory into the todo list */
832 if (!(n = newDirTodo())) {
833 perror("No space for todo list");
836 n->next = pendingDirectories;
838 pendingDirectories = n;
840 mod |= k = checksize(boot, fat, p, &dirent);
847 if (!(boot->flags & FAT32) && !dir->parent)
852 if (lseek(f, off, SEEK_SET) != off
853 || write(f, buffer, last) != last) {
854 perror("Unable to write directory");
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,
866 /* The root directory of non fat32 filesystems is in a special
867 * area and may have been modified above without being written out.
869 if ((mod & FSDIRMOD) && !(boot->flags & FAT32) && !dir->parent) {
871 if (lseek(f, off, SEEK_SET) != off
872 || write(f, buffer, last) != last) {
873 perror("Unable to write directory");
878 return mod & ~THISMOD;
882 handleDirTree(int dosfs, struct bootblock *boot, struct fatEntry *fat)
886 mod = readDosDirSection(dosfs, boot, fat, rootDir);
891 * process the directory todo list
893 while (pendingDirectories) {
894 struct dosDirEntry *dir = pendingDirectories->dir;
895 struct dirTodoNode *n = pendingDirectories->next;
898 * remove TODO entry now, the list might change during
901 freeDirTodo(pendingDirectories);
902 pendingDirectories = n;
905 * handle subdirectory
907 mod |= readDosDirSection(dosfs, boot, fat, dir);
916 * Try to reconnect a FAT chain into dir
918 static u_char *lfbuf;
923 reconnect(int dosfs, struct bootblock *boot, struct fatEntry *fat, cl_t head)
925 struct dosDirEntry d;
928 if (!ask(1, "Reconnect"))
932 for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) {
933 if (!strcmp(lostDir->name, LOSTDIR))
936 if (!lostDir) { /* Create LOSTDIR? XXX */
937 pwarn("No %s directory\n", LOSTDIR);
942 lfbuf = malloc(boot->ClusterSize);
944 perror("No space for buffer");
952 for (; p < lfbuf + boot->ClusterSize; p += 32)
954 || *p == SLOT_DELETED)
956 if (p && p < lfbuf + boot->ClusterSize)
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);
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");
975 /* Ensure uniqueness of entry here! XXX */
976 memset(&d, 0, sizeof d);
977 (void)snprintf(d.name, sizeof(d.name), "%u", head);
980 d.size = fat[head].length * boot->ClusterSize;
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);
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");