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 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->RootDirEnts * 32;
223 b2 = boot->SecPerClust * boot->BytesPerSec;
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->RootCl < CLUST_FIRST || boot->RootCl >= boot->NumClusters) {
246 pfatal("Root directory starts with cluster out of range(%u)",
250 cl = fat[boot->RootCl].next;
252 || (cl >= CLUST_RSRVD && cl< CLUST_EOFS)
253 || fat[boot->RootCl].head != boot->RootCl) {
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",
260 pfatal("Root directory doesn't start a cluster chain");
264 fat[boot->RootCl].next = CLUST_FREE;
270 fat[boot->RootCl].flags |= FAT_USED;
271 rootDir->head = boot->RootCl;
278 * Cleanup after a directory scan
281 finishDosDirSection(void)
283 struct dirTodoNode *p, *np;
284 struct dosDirEntry *d, *nd;
286 for (p = pendingDirectories; p; p = np) {
290 pendingDirectories = 0;
291 for (d = rootDir; d; d = nd) {
292 if ((nd = d->child) != NULL) {
300 rootDir = lostDir = NULL;
308 * Delete directory entries between startcl, startoff and endcl, endoff.
311 delete(int f, struct bootblock *boot, struct fatEntry *fat, cl_t startcl,
312 int startoff, cl_t endcl, int endoff, int notlast)
316 int clsz = boot->SecPerClust * boot->BytesPerSec;
318 s = delbuf + startoff;
320 while (startcl >= CLUST_FIRST && startcl < boot->NumClusters) {
321 if (startcl == endcl) {
326 off = startcl * boot->SecPerClust + boot->ClusterOffset;
327 off *= boot->BytesPerSec;
328 if (lseek(f, off, SEEK_SET) != off
329 || read(f, delbuf, clsz) != clsz) {
330 perror("Unable to read directory");
337 if (lseek(f, off, SEEK_SET) != off
338 || write(f, delbuf, clsz) != clsz) {
339 perror("Unable to write directory");
342 if (startcl == endcl)
344 startcl = fat[startcl].next;
351 removede(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)
356 pwarn("Invalid long filename entry for %s\n", path);
359 pwarn("Invalid long filename entry at end of directory %s\n", path);
362 pwarn("Invalid long filename entry for volume label\n");
365 if (ask(0, "Remove")) {
366 if (startcl != curcl) {
367 if (delete(f, boot, fat,
368 startcl, start - buffer,
370 endcl == curcl) == FSFATAL)
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;
384 * Check an in-memory file entry
387 checksize(struct bootblock *boot, struct fatEntry *fat, u_char *p,
388 struct dosDirEntry *dir)
391 * Check size on ordinary files
393 u_int32_t physicalSize;
395 if (dir->head == CLUST_FREE)
398 if (dir->head < CLUST_FIRST || dir->head >= boot->NumClusters)
400 physicalSize = fat[dir->head].length * boot->ClusterSize;
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);
414 } else if (physicalSize - dir->size >= boot->ClusterSize) {
415 pwarn("%s has too many clusters allocated\n",
417 if (ask(1, "Drop superfluous clusters")) {
421 for (cl = dir->head; (sz += boot->ClusterSize) < dir->size;)
423 clearchain(boot, fat, fat[cl].next);
424 fat[cl].next = CLUST_EOF;
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
439 readDosDirSection(int f, struct bootblock *boot, struct fatEntry *fat,
440 struct dosDirEntry *dir)
442 struct dosDirEntry dirent, *d;
443 u_char *p, *vallfn, *invlfn, *empty;
446 cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0;
451 #define THISMOD 0x8000 /* Only used within this routine */
454 if (dir->parent && (cl < CLUST_FIRST || cl >= boot->NumClusters)) {
456 * Already handled somewhere else.
461 vallfn = invlfn = empty = NULL;
463 if (!(boot->flags & FAT32) && !dir->parent) {
464 last = boot->RootDirEnts * 32;
465 off = boot->ResSectors + boot->FATs * boot->FATsecs;
467 last = boot->SecPerClust * boot->BytesPerSec;
468 off = cl * boot->SecPerClust + boot->ClusterOffset;
471 off *= boot->BytesPerSec;
472 if (lseek(f, off, SEEK_SET) != off
473 || read(f, buffer, last) != last) {
474 perror("Unable to read directory");
479 * Check `.' and `..' entries here? XXX
481 for (p = buffer, i = 0; i < last; i++, p += 32) {
482 if (dir->fsckflags & DIREMPWARN) {
487 if (*p == SLOT_EMPTY || *p == SLOT_DELETED) {
488 if (*p == SLOT_EMPTY) {
489 dir->fsckflags |= DIREMPTY;
496 if (dir->fsckflags & DIREMPTY) {
497 if (!(dir->fsckflags & DIREMPWARN)) {
498 pwarn("%s has entries after end of directory\n",
500 if (ask(1, "Extend")) {
503 dir->fsckflags &= ~DIREMPTY;
504 if (delete(f, boot, fat,
505 empcl, empty - buffer,
506 cl, p - buffer, 1) == FSFATAL)
508 q = empcl == cl ? empty : buffer;
509 for (; q < p; q += 32)
511 mod |= THISMOD|FSDIRMOD;
512 } else if (ask(0, "Truncate"))
513 dir->fsckflags |= DIREMPWARN;
515 if (dir->fsckflags & DIREMPWARN) {
517 mod |= THISMOD|FSDIRMOD;
519 } else if (dir->fsckflags & DIREMPTY)
524 if (p[11] == ATTR_WIN95) {
526 if (shortSum != -1) {
532 memset(longName, 0, sizeof longName);
536 } else if (shortSum != p[13]
537 || lidx != (*p & LRNOMASK)) {
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])
555 * Warn about those unusable chars in msdosfs here? XXX
561 for (k = 14; k < 26 && t < longName + sizeof(longName); k += 2) {
562 if (!p[k] && !p[k + 1])
569 for (k = 28; k < 32 && t < longName + sizeof(longName); k += 2) {
570 if (!p[k] && !p[k + 1])
576 if (t >= longName + sizeof(longName)) {
577 pwarn("long filename too long\n");
584 if (p[26] | (p[27] << 8)) {
585 pwarn("long filename record cluster start != 0\n");
592 continue; /* long records don't carry further
597 * This is a standard msdosfs directory entry.
599 memset(&dirent, 0, sizeof dirent);
602 * it's a short name record, but we need to know
603 * more, so get the flags first.
605 dirent.flags = p[11];
608 * Translate from 850 to ISO here XXX
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')
617 if (dirent.name[0] == SLOT_E5)
618 dirent.name[0] = 0xe5;
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,
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';
640 if (vallfn && shortSum != calcShortSum(p)) {
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);
652 strlcpy(dirent.lname, longName,
653 sizeof(dirent.lname));
659 dirent.next = dir->child;
662 mod |= k = removede(f, boot, fat,
663 invlfn, vallfn ? vallfn : p,
664 invcl, vallfn ? valcl : cl, cl,
665 fullpath(&dirent), 0);
669 ? (valcl == cl && vallfn != buffer)
675 vallfn = NULL; /* not used any longer */
678 if (dirent.size == 0 && !(dirent.flags & ATTR_DIRECTORY)) {
679 if (dirent.head != 0) {
680 pwarn("%s has clusters, but size 0\n",
682 if (ask(1, "Drop allocated clusters")) {
684 if (boot->ClustMask == CLUST32_MASK)
686 clearchain(boot, fat, dirent.head);
688 mod |= THISMOD|FSDIRMOD|FSFATMOD;
692 } else if (dirent.head == 0
693 && !strcmp(dirent.name, "..")
694 && dir->parent /* XXX */
695 && !dir->parent->parent) {
697 * Do nothing, the parent is the root
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",
708 else if (dirent.head < CLUST_FIRST
709 || dirent.head >= boot->NumClusters)
710 pwarn("%s starts with cluster out of range(%u)\n",
713 else if (fat[dirent.head].next == CLUST_FREE)
714 pwarn("%s starts with free cluster\n",
716 else if (fat[dirent.head].next >= CLUST_RSRVD)
717 pwarn("%s starts with cluster marked %s\n",
719 rsrvdcltype(fat[dirent.head].next));
721 pwarn("%s doesn't start a cluster chain\n",
723 if (dirent.flags & ATTR_DIRECTORY) {
724 if (ask(0, "Remove")) {
726 mod |= THISMOD|FSDIRMOD;
731 if (ask(1, "Truncate")) {
732 p[28] = p[29] = p[30] = p[31] = 0;
734 if (boot->ClustMask == CLUST32_MASK)
737 mod |= THISMOD|FSDIRMOD;
743 if (dirent.head >= CLUST_FIRST && dirent.head < boot->NumClusters)
744 fat[dirent.head].flags |= FAT_USED;
746 if (dirent.flags & ATTR_DIRECTORY) {
748 * gather more info for directories
750 struct dirTodoNode *n;
753 pwarn("Directory %s has size != 0\n",
755 if (ask(1, "Correct")) {
756 p[28] = p[29] = p[30] = p[31] = 0;
758 mod |= THISMOD|FSDIRMOD;
763 * handle `.' and `..' specially
765 if (strcmp(dirent.name, ".") == 0) {
766 if (dirent.head != dir->head) {
767 pwarn("`.' entry in %s has incorrect start cluster\n",
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);
777 mod |= THISMOD|FSDIRMOD;
783 if (strcmp(dirent.name, "..") == 0) {
784 if (dir->parent) { /* XXX */
785 if (!dir->parent->parent) {
787 pwarn("`..' entry in %s has non-zero start cluster\n",
789 if (ask(1, "Correct")) {
792 if (boot->ClustMask == CLUST32_MASK)
794 mod |= THISMOD|FSDIRMOD;
798 } else if (dirent.head != dir->parent->head) {
799 pwarn("`..' entry in %s has incorrect start cluster\n",
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);
809 mod |= THISMOD|FSDIRMOD;
817 /* create directory tree node */
818 if (!(d = newDosDirEntry())) {
819 perror("No space for directory");
822 memcpy(d, &dirent, sizeof(struct dosDirEntry));
823 /* link it into the tree */
826 /* Enter this directory into the todo list */
827 if (!(n = newDirTodo())) {
828 perror("No space for todo list");
831 n->next = pendingDirectories;
833 pendingDirectories = n;
835 mod |= k = checksize(boot, fat, p, &dirent);
842 if (!(boot->flags & FAT32) && !dir->parent)
847 if (lseek(f, off, SEEK_SET) != off
848 || write(f, buffer, last) != last) {
849 perror("Unable to write directory");
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,
861 /* The root directory of non fat32 filesystems is in a special
862 * area and may have been modified above without being written out.
864 if ((mod & FSDIRMOD) && !(boot->flags & FAT32) && !dir->parent) {
866 if (lseek(f, off, SEEK_SET) != off
867 || write(f, buffer, last) != last) {
868 perror("Unable to write directory");
873 return mod & ~THISMOD;
877 handleDirTree(int dosfs, struct bootblock *boot, struct fatEntry *fat)
881 mod = readDosDirSection(dosfs, boot, fat, rootDir);
886 * process the directory todo list
888 while (pendingDirectories) {
889 struct dosDirEntry *dir = pendingDirectories->dir;
890 struct dirTodoNode *n = pendingDirectories->next;
893 * remove TODO entry now, the list might change during
896 freeDirTodo(pendingDirectories);
897 pendingDirectories = n;
900 * handle subdirectory
902 mod |= readDosDirSection(dosfs, boot, fat, dir);
911 * Try to reconnect a FAT chain into dir
913 static u_char *lfbuf;
918 reconnect(int dosfs, struct bootblock *boot, struct fatEntry *fat, cl_t head)
920 struct dosDirEntry d;
923 if (!ask(1, "Reconnect"))
927 for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) {
928 if (!strcmp(lostDir->name, LOSTDIR))
931 if (!lostDir) { /* Create LOSTDIR? XXX */
932 pwarn("No %s directory\n", LOSTDIR);
937 lfbuf = malloc(boot->ClusterSize);
939 perror("No space for buffer");
947 for (; p < lfbuf + boot->ClusterSize; p += 32)
949 || *p == SLOT_DELETED)
951 if (p && p < lfbuf + boot->ClusterSize)
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);
959 lfoff = lfcl * boot->ClusterSize
960 + boot->ClusterOffset * boot->BytesPerSec;
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");
970 /* Ensure uniqueness of entry here! XXX */
971 memset(&d, 0, sizeof d);
972 (void)snprintf(d.name, sizeof(d.name), "%u", head);
975 d.size = fat[head].length * boot->ClusterSize;
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);
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");