2 * Copyright 2000, International Business Machines Corporation and others.
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
10 #include <afsconfig.h>
11 #include <afs/param.h>
14 # if !defined(UKERNEL)
16 # if !defined(AFS_LINUX26_ENV)
22 # include "h/sysmacros.h"
23 # include "h/signal.h"
27 # if defined(AFS_AIX_ENV) || defined(AFS_SGI_ENV) || defined(AFS_SUN5_ENV) || defined(AFS_LINUX20_ENV)
30 # if !defined(AFS_SUN5_ENV) && !defined(AFS_LINUX20_ENV)
31 # include "h/kernel.h"
34 # if defined(AFS_SUN5_ENV) || defined(AFS_HPUX_ENV) || defined(AFS_FBSD_ENV) || defined(AFS_DARWIN80_ENV)
35 # include "afs/sysincludes.h"
37 # if !defined(AFS_SGI64_ENV) && !defined(AFS_DARWIN_ENV) && !defined(AFS_OBSD48_ENV) && !defined(AFS_NBSD_ENV)
39 # endif /* AFS_SGI64_ENV */
41 # if !defined(AFS_SUN5_ENV) && !defined(AFS_LINUX20_ENV) && !defined(AFS_HPUX110_ENV)
44 # ifndef AFS_LINUX20_ENV
45 # include "netinet/in.h"
47 # else /* !defined(UKERNEL) */
48 # include "afs/stds.h"
49 # include "afs/sysincludes.h"
50 # endif /* !defined(UKERNEL) */
53 /* These are needed because afs_prototypes.h is not included here */
56 extern int DRead(struct dcache *adc, int page, struct DirBuffer *);
57 extern int DNew(struct dcache *adc, int page, struct DirBuffer *);
59 # include "afs/afs_osi.h"
63 # ifdef AFS_LINUX20_ENV
64 # include "h/string.h"
73 /* Local static prototypes */
74 static int FindBlobs(dir_file_t, int);
75 static int AddPage(dir_file_t, int);
76 static void FreeBlobs(dir_file_t, int, int);
77 static int FindItem(dir_file_t, char *, struct DirBuffer *,
80 /* Find out how many entries are required to store a name. */
82 afs_dir_NameBlobs(char *name)
86 return 1 + ((i + 15) >> 5);
89 /* Create an entry in a file. Dir is a file representation, while entry is
92 afs_dir_Create(dir_file_t dir, char *entry, void *voidfid)
94 afs_int32 *vfid = (afs_int32 *) voidfid;
97 struct DirBuffer entrybuf, prevbuf, headerbuf;
99 struct DirHeader *dhp;
102 /* check name quality */
106 /* First check if file already exists. */
107 code = FindItem(dir, entry, &prevbuf, &entrybuf);
108 if (code && code != ENOENT) {
112 DRelease(&entrybuf, 0);
113 DRelease(&prevbuf, 0);
117 blobs = afs_dir_NameBlobs(entry); /* number of entries required */
118 firstelt = FindBlobs(dir, blobs);
120 return EFBIG; /* directory is full */
122 /* First, we fill in the directory entry. */
123 if (afs_dir_GetBlob(dir, firstelt, &entrybuf) != 0)
125 ep = (struct DirEntry *)entrybuf.data;
128 ep->fid.vnode = htonl(vfid[1]);
129 ep->fid.vunique = htonl(vfid[2]);
130 strcpy(ep->name, entry);
132 /* Now we just have to thread it on the hash table list. */
133 if (DRead(dir, 0, &headerbuf) != 0) {
134 DRelease(&entrybuf, 1);
137 dhp = (struct DirHeader *)headerbuf.data;
139 i = afs_dir_DirHash(entry);
140 ep->next = dhp->hashTable[i];
141 dhp->hashTable[i] = htons(firstelt);
142 DRelease(&headerbuf, 1);
143 DRelease(&entrybuf, 1);
148 afs_dir_Length(dir_file_t dir)
151 struct DirBuffer headerbuf;
152 struct DirHeader *dhp;
154 if (DRead(dir, 0, &headerbuf) != 0)
156 dhp = (struct DirHeader *)headerbuf.data;
158 if (dhp->header.pgcount != 0)
159 ctr = ntohs(dhp->header.pgcount);
161 /* old style, count the pages */
163 for (i = 0; i < MAXPAGES; i++)
164 if (dhp->alloMap[i] != EPP)
167 DRelease(&headerbuf, 0);
168 return ctr * AFS_PAGESIZE;
171 /* Delete an entry from a directory, including update of all free entry
174 afs_dir_Delete(dir_file_t dir, char *entry)
178 struct DirBuffer entrybuf, prevbuf;
179 struct DirEntry *firstitem;
180 unsigned short *previtem;
183 code = FindItem(dir, entry, &prevbuf, &entrybuf);
188 firstitem = (struct DirEntry *)entrybuf.data;
189 previtem = (unsigned short *)prevbuf.data;
191 *previtem = firstitem->next;
192 DRelease(&prevbuf, 1);
193 index = DVOffset(&entrybuf) / 32;
194 nitems = afs_dir_NameBlobs(firstitem->name);
195 /* Clear entire DirEntry and any DirXEntry extensions */
196 memset(firstitem, 0, nitems * sizeof(*firstitem));
197 DRelease(&entrybuf, 1);
198 FreeBlobs(dir, index, nitems);
203 * Find a bunch of contiguous entries; at least nblobs in a row.
205 * \param dir pointer to the directory object
206 * \param nblobs number of contiguous entries we need
208 * \return element number (directory entry) of the requested space
209 * \retval -1 failed to find 'nblobs' contiguous entries
212 FindBlobs(dir_file_t dir, int nblobs)
216 struct DirBuffer headerbuf, pagebuf;
217 struct DirHeader *dhp;
218 struct PageHeader *pp;
222 /* read the dir header in first. */
223 if (DRead(dir, 0, &headerbuf) != 0)
225 dhp = (struct DirHeader *)headerbuf.data;
227 for (i = 0; i < BIGMAXPAGES; i++) {
228 if (i >= MAXPAGES || dhp->alloMap[i] >= nblobs) {
229 /* if page could contain enough entries */
230 /* If there are EPP free entries, then the page is not even allocated. */
232 /* this pages exists past the end of the old-style dir */
233 pgcount = ntohs(dhp->header.pgcount);
236 dhp->header.pgcount = htons(pgcount);
238 if (i > pgcount - 1) {
239 /* this page is bigger than last allocated page */
240 code = AddPage(dir, i);
243 dhp->header.pgcount = htons(i + 1);
245 } else if (dhp->alloMap[i] == EPP) {
246 /* Add the page to the directory. */
247 code = AddPage(dir, i);
250 dhp->alloMap[i] = EPP - 1;
251 dhp->header.pgcount = htons(i + 1);
254 /* read the page in. */
255 if (DRead(dir, i, &pagebuf) != 0) {
258 pp = (struct PageHeader *)pagebuf.data;
259 for (j = 0; j <= EPP - nblobs; j++) {
261 for (k = 0; k < nblobs; k++)
262 if ((pp->freebitmap[(j + k) >> 3] >> ((j + k) & 7)) & 1) {
271 /* Here we have the first index in j. We update the allocation maps
272 * and free up any resources we've got allocated. */
274 dhp->alloMap[i] -= nblobs;
275 DRelease(&headerbuf, 1);
276 for (k = 0; k < nblobs; k++)
277 pp->freebitmap[(j + k) >> 3] |= 1 << ((j + k) & 7);
278 DRelease(&pagebuf, 1);
281 DRelease(&pagebuf, 0); /* This dir page is unchanged. */
284 /* If we make it here, the directory is full, or we encountered an I/O error. */
285 DRelease(&headerbuf, 1);
290 * Add a page to a directory object.
292 * \param dir pointer to the directory object
293 * \param pageno page number to add
296 * \retval non-zero return error from DNew
299 AddPage(dir_file_t dir, int pageno)
300 { /* Add a page to a directory. */
302 struct PageHeader *pp;
303 struct DirBuffer pagebuf;
306 /* Get a new buffer labelled dir,pageno */
307 code = DNew(dir, pageno, &pagebuf);
310 pp = (struct PageHeader *)pagebuf.data;
312 pp->tag = htons(1234);
315 pp->freecount = EPP - 1; /* The first dude is already allocated */
316 pp->freebitmap[0] = 0x01;
317 for (i = 1; i < EPP / 8; i++) /* It's a constant */
318 pp->freebitmap[i] = 0;
319 DRelease(&pagebuf, 1);
323 /* Free a whole bunch of directory entries. */
326 FreeBlobs(dir_file_t dir, int firstblob, int nblobs)
330 struct DirBuffer headerbuf, pagehdbuf;
331 struct DirHeader *dhp;
332 struct PageHeader *pp;
333 page = firstblob / EPP;
334 firstblob -= EPP * page; /* convert to page-relative entry */
336 if (DRead(dir, 0, &headerbuf) != 0)
338 dhp = (struct DirHeader *)headerbuf.data;
341 dhp->alloMap[page] += nblobs;
343 DRelease(&headerbuf, 1);
345 if (DRead(dir, page, &pagehdbuf) != 0)
347 pp = (struct PageHeader *)pagehdbuf.data;
349 for (i = 0; i < nblobs; i++)
350 pp->freebitmap[(firstblob + i) >> 3] &= ~(1 << ((firstblob + i) & 7));
352 DRelease(&pagehdbuf, 1);
356 * Format an empty directory properly. Note that the first 13 entries in a
357 * directory header page are allocated, 1 to the page header, 4 to the
358 * allocation map and 8 to the hash table.
360 * \param dir pointer to the directory object
361 * \param me fid (vnode+uniq) for new dir
362 * \param parent fid (vnode+uniq) for parent dir
365 * \retval nonzero error code
368 afs_dir_MakeDir(dir_file_t dir, afs_int32 * me, afs_int32 * parent)
371 struct DirBuffer buffer;
372 struct DirHeader *dhp;
375 code = DNew(dir, 0, &buffer);
378 dhp = (struct DirHeader *)buffer.data;
380 dhp->header.pgcount = htons(1);
381 dhp->header.tag = htons(1234);
382 dhp->header.freecount = (EPP - DHE - 1);
383 dhp->header.freebitmap[0] = 0xff;
384 dhp->header.freebitmap[1] = 0x1f;
385 for (i = 2; i < EPP / 8; i++)
386 dhp->header.freebitmap[i] = 0;
387 dhp->alloMap[0] = (EPP - DHE - 1);
388 for (i = 1; i < MAXPAGES; i++)
389 dhp->alloMap[i] = EPP;
390 for (i = 0; i < NHASHENT; i++)
391 dhp->hashTable[i] = 0;
392 DRelease(&buffer, 1);
393 code = afs_dir_Create(dir, ".", me);
396 code = afs_dir_Create(dir, "..", parent);
402 /* Look up a file name in directory. */
405 afs_dir_Lookup(dir_file_t dir, char *entry, void *voidfid)
407 afs_int32 *fid = (afs_int32 *) voidfid;
408 struct DirBuffer firstbuf, prevbuf;
409 struct DirEntry *firstitem;
412 code = FindItem(dir, entry, &prevbuf, &firstbuf);
416 DRelease(&prevbuf, 0);
417 firstitem = (struct DirEntry *)firstbuf.data;
419 fid[1] = ntohl(firstitem->fid.vnode);
420 fid[2] = ntohl(firstitem->fid.vunique);
421 DRelease(&firstbuf, 0);
425 /* Look up a file name in directory. */
428 afs_dir_LookupOffset(dir_file_t dir, char *entry, void *voidfid,
431 afs_int32 *fid = (afs_int32 *) voidfid;
432 struct DirBuffer firstbuf, prevbuf;
433 struct DirEntry *firstitem;
436 code = FindItem(dir, entry, &prevbuf, &firstbuf);
440 DRelease(&prevbuf, 0);
441 firstitem = (struct DirEntry *)firstbuf.data;
443 fid[1] = ntohl(firstitem->fid.vnode);
444 fid[2] = ntohl(firstitem->fid.vunique);
446 *offsetp = DVOffset(&firstbuf);
447 DRelease(&firstbuf, 0);
452 * Enumerate the contents of a directory. Break when hook function
457 afs_dir_EnumerateDir(dir_file_t dir, int (*proc) (void *, char *name,
464 struct DirBuffer headerbuf, entrybuf;
465 struct DirHeader *dhp;
470 if (DRead(dir, 0, &headerbuf) != 0)
472 dhp = (struct DirHeader *)headerbuf.data;
474 for (i = 0; i < NHASHENT; i++) {
475 /* For each hash chain, enumerate everyone on the list. */
476 num = ntohs(dhp->hashTable[i]);
478 while (num != 0 && elements < BIGMAXPAGES * EPP) {
481 /* Walk down the hash table list. */
482 code = afs_dir_GetVerifiedBlob(dir, num, &entrybuf);
486 ep = (struct DirEntry *)entrybuf.data;
488 DRelease(&entrybuf, 0);
492 num = ntohs(ep->next);
493 code = (*proc) (hook, ep->name, ntohl(ep->fid.vnode),
494 ntohl(ep->fid.vunique));
495 DRelease(&entrybuf, 0);
502 DRelease(&headerbuf, 0);
507 afs_dir_IsEmpty(dir_file_t dir)
509 /* Enumerate the contents of a directory. */
512 struct DirBuffer headerbuf, entrybuf;
513 struct DirHeader *dhp;
517 if (DRead(dir, 0, &headerbuf) != 0)
519 dhp = (struct DirHeader *)headerbuf.data;
521 for (i = 0; i < NHASHENT; i++) {
522 /* For each hash chain, enumerate everyone on the list. */
523 num = ntohs(dhp->hashTable[i]);
525 while (num != 0 && elements < BIGMAXPAGES * EPP) {
527 /* Walk down the hash table list. */
528 if (afs_dir_GetVerifiedBlob(dir, num, &entrybuf) != 0)
530 ep = (struct DirEntry *)entrybuf.data;
531 if (strcmp(ep->name, "..") && strcmp(ep->name, ".")) {
532 DRelease(&entrybuf, 0);
533 DRelease(&headerbuf, 0);
536 num = ntohs(ep->next);
537 DRelease(&entrybuf, 0);
540 DRelease(&headerbuf, 0);
544 /* Return a pointer to an entry, given its number. Also return the maximum
545 * size of the entry, which is determined by its position within the directory
548 * If physerr is supplied by caller, it will be set to:
549 * 0 for logical errors
550 * errno for physical errors
553 GetBlobWithLimit(dir_file_t dir, afs_int32 blobno,
554 struct DirBuffer *buffer, afs_size_t *maxlen, int *physerr)
560 memset(buffer, 0, sizeof(struct DirBuffer));
562 code = DReadWithErrno(dir, blobno >> LEPP, buffer, physerr);
566 pos = 32 * (blobno & (EPP - 1));
568 *maxlen = AFS_PAGESIZE - pos - 1;
570 buffer->data = (void *)(((char *)buffer->data) + pos);
576 * Given an entry's number, return a pointer to that entry.
577 * If physerr is supplied by caller, it will be set to:
578 * 0 for logical errors
579 * errno for physical errors
582 afs_dir_GetBlobWithErrno(dir_file_t dir, afs_int32 blobno, struct DirBuffer *buffer,
585 afs_size_t maxlen = 0;
586 return GetBlobWithLimit(dir, blobno, buffer, &maxlen, physerr);
589 /* Given an entries number, return a pointer to that entry */
591 afs_dir_GetBlob(dir_file_t dir, afs_int32 blobno, struct DirBuffer *buffer)
593 afs_size_t maxlen = 0;
594 return GetBlobWithLimit(dir, blobno, buffer, &maxlen, NULL);
597 /* Return an entry, having verified that the name held within the entry
598 * doesn't overflow off the end of the directory page it is contained
603 afs_dir_GetVerifiedBlob(dir_file_t file, afs_int32 blobno,
604 struct DirBuffer *outbuf)
606 struct DirEntry *dir;
607 struct DirBuffer buffer;
612 code = GetBlobWithLimit(file, blobno, &buffer, &maxlen, NULL);
616 dir = (struct DirEntry *)buffer.data;
618 /* A blob is only valid if the name within it is NULL terminated before
619 * the end of the blob's containing page */
620 for (cp = dir->name; *cp != '\0' && cp < ((char *)dir) + maxlen; cp++);
623 DRelease(&buffer, 0);
632 afs_dir_DirHash(char *string)
634 /* Hash a string to a number between 0 and NHASHENT. */
639 while ((tc = (*string++))) {
643 tval = hval & (NHASHENT - 1);
646 else if (hval >= 1u<<31)
647 tval = NHASHENT - tval;
652 /* Find a directory entry, given its name. This entry returns a pointer
653 * to a locked buffer, and a pointer to a locked buffer (in previtem)
654 * referencing the found item (to aid the delete code). If no entry is
655 * found, however, no items are left locked, and a null pointer is
656 * returned instead. */
659 FindItem(dir_file_t dir, char *ename, struct DirBuffer *prevbuf,
660 struct DirBuffer *itembuf )
663 struct DirBuffer curr, prev;
664 struct DirHeader *dhp;
668 memset(prevbuf, 0, sizeof(struct DirBuffer));
669 memset(itembuf, 0, sizeof(struct DirBuffer));
671 code = DRead(dir, 0, &prev);
674 dhp = (struct DirHeader *)prev.data;
676 i = afs_dir_DirHash(ename);
677 if (dhp->hashTable[i] == 0) {
683 code = afs_dir_GetVerifiedBlob(dir,
684 (u_short) ntohs(dhp->hashTable[i]),
690 prev.data = &(dhp->hashTable[i]);
692 /* Detect circular hash chains. Absolute max size of a directory */
693 while (elements < BIGMAXPAGES * EPP) {
696 /* Look at each entry on the hash chain */
697 tp = (struct DirEntry *)curr.data;
698 if (!strcmp(ename, tp->name)) {
708 prev.data = &(tp->next);
711 /* The end of the line */
716 code = afs_dir_GetVerifiedBlob(dir, (u_short) ntohs(tp->next),
722 /* If we've reached here, we've hit our loop limit. Something is weird with
723 * the directory; maybe a circular hash chain? */
732 FindFid (void *dir, afs_uint32 vnode, afs_uint32 unique,
733 struct DirBuffer *itembuf)
735 /* Find a directory entry, given the vnode and uniquifier of a object.
736 * This entry returns a pointer to a locked buffer. If no entry is found,
737 * however, no items are left locked, and a null pointer is returned
742 struct DirBuffer curr, header;
743 struct DirHeader *dhp;
747 memset(itembuf, 0, sizeof(struct DirBuffer));
749 code = DRead(dir, 0, &header);
752 dhp = (struct DirHeader *)header.data;
754 for (i=0; i<NHASHENT; i++) {
755 if (dhp->hashTable[i] != 0) {
756 code = afs_dir_GetVerifiedBlob(dir,
757 (u_short)ntohs(dhp->hashTable[i]),
760 DRelease(&header, 0);
764 while(curr.data != NULL && elements < BIGMAXPAGES * EPP) {
766 tp = (struct DirEntry *)curr.data;
768 if (vnode == ntohl(tp->fid.vnode)
769 && unique == ntohl(tp->fid.vunique)) {
770 DRelease(&header, 0);
781 code = afs_dir_GetVerifiedBlob(dir, (u_short)ntohs(next),
784 DRelease(&header, 0);
790 DRelease(&header, 0);
795 afs_dir_InverseLookup(void *dir, afs_uint32 vnode, afs_uint32 unique,
796 char *name, afs_uint32 length)
798 /* Look for the name pointing to given vnode and unique in a directory */
799 struct DirBuffer entrybuf;
800 struct DirEntry *entry;
803 code = FindFid(dir, vnode, unique, &entrybuf);
807 entry = (struct DirEntry *)entrybuf.data;
809 if (strlen(entry->name) >= length)
812 strcpy(name, entry->name);
813 DRelease(&entrybuf, 0);
818 * Change an entry fid.
821 * \param entry The entry name.
822 * \param old_fid The old find in MKFid format (host order).
823 * It can be omitted if you don't need a safety check...
824 * \param new_fid The new find in MKFid format (host order).
827 afs_dir_ChangeFid(dir_file_t dir, char *entry, afs_uint32 *old_fid,
830 struct DirBuffer prevbuf, entrybuf;
831 struct DirEntry *firstitem;
832 struct MKFid *fid_old = (struct MKFid *) old_fid;
833 struct MKFid *fid_new = (struct MKFid *) new_fid;
837 code = FindItem(dir, entry, &prevbuf, &entrybuf);
841 firstitem = (struct DirEntry *)entrybuf.data;
842 DRelease(&prevbuf, 1);
846 ((htonl(fid_old->vnode) == firstitem->fid.vnode) &&
847 (htonl(fid_old->vunique) == firstitem->fid.vunique))) {
849 firstitem->fid.vnode = htonl(fid_new->vnode);
850 firstitem->fid.vunique = htonl(fid_new->vunique);
853 DRelease(&entrybuf, 1);