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>
17 #include <afs/bubasics.h>
19 #include "budb_errs.h"
21 #include "budb_internal.h"
22 #include "error_macros.h"
25 int sizeFunctions[HT_MAX_FUNCTION + 1];
26 int nHTBuckets = NhtBucketS; /* testing: we need small HT blocks */
28 int ht_minHBlocks(struct memoryHashTable *mht);
30 /* ht_TableSize - return the size of table necessary to represent a hashtable
31 * of given length in memory. It basically rounds the length up by the number
32 * of buckets per block. */
35 ht_TableSize(int length)
40 n = (length + nHTBuckets - 1) / nHTBuckets;
41 return n * sizeof(struct memoryHTBlock *);
44 /* ht_ResetT - resets the in-memory representation of a hashtable block array.
45 * It also resets the global variable nHTBuckets. */
48 ht_ResetT(struct memoryHTBlock ***blocksP, int *sizeP, int length)
50 struct memoryHTBlock **b = *blocksP;
55 nHTBuckets = ntohl(db.h.nHTBuckets);
57 n = *sizeP / sizeof(b[0]);
58 newsize = ht_TableSize(length);
59 if (*sizeP != newsize) {
60 /* free all blocks in the old array */
61 for (i = 0; i < n; i++)
68 /* invalidate the blocks of the array */
69 for (i = 0; i < n; i++)
77 * reinitialize a memory hash table.
78 * Calls ht_ResetT to invalidate the two block arrays.
82 ht_Reset(struct memoryHashTable *mht)
84 struct hashTable *ht = NULL;
86 if (!(mht && (ht = mht->ht)))
87 db_panic("some ht called with bad mht");
88 mht->threadOffset = ntohl(ht->threadOffset);
89 mht->length = ntohl(ht->length);
90 mht->oldLength = ntohl(ht->oldLength);
91 mht->progress = ntohl(ht->progress);
92 ht_ResetT(&mht->blocks, &mht->size, mht->length);
93 ht_ResetT(&mht->oldBlocks, &mht->oldSize, mht->oldLength);
96 /* InitDBhash - When server starts, do hash table initialization.
97 test - initialization parameters: bit 4 is small ht. */
102 sizeFunctions[0] = 0;
104 sizeFunctions[HT_dumpIden_FUNCTION] = sizeof(struct dump);
105 sizeFunctions[HT_dumpName_FUNCTION] = sizeof(struct dump);
106 sizeFunctions[HT_volName_FUNCTION] = sizeof(struct volInfo);
107 sizeFunctions[HT_tapeName_FUNCTION] = sizeof(struct tape);
109 db.volName.ht = &db.h.volName;
110 db.tapeName.ht = &db.h.tapeName;
111 db.dumpName.ht = &db.h.dumpName;
112 db.dumpIden.ht = &db.h.dumpIden;
116 /* ht_DBInit - When rebuilding database, this sets up the hash tables. */
121 db.h.nHTBuckets = htonl(nHTBuckets);
124 struct volInfo *s = 0;
125 db.h.volName.threadOffset =
126 htonl((char *)&s->nameHashChain - (char *)s);
127 db.h.volName.functionType = htonl(HT_volName_FUNCTION);
131 db.h.tapeName.threadOffset =
132 htonl((char *)&s->nameHashChain - (char *)s);
133 db.h.tapeName.functionType = htonl(HT_tapeName_FUNCTION);
137 db.h.dumpName.threadOffset =
138 htonl((char *)&s->nameHashChain - (char *)s);
139 db.h.dumpName.functionType = htonl(HT_dumpName_FUNCTION);
141 db.h.dumpIden.threadOffset =
142 htonl((char *)&s->idHashChain - (char *)s);
143 db.h.dumpIden.functionType = htonl(HT_dumpIden_FUNCTION);
145 ht_Reset(&db.volName);
146 ht_Reset(&db.tapeName);
147 ht_Reset(&db.dumpName);
148 ht_Reset(&db.dumpIden);
152 ht_AllocTable(struct ubik_trans *ut, struct memoryHashTable *mht)
154 struct hashTable *ht = NULL;
157 int nb, mnb; /* number of blocks for hashTable */
159 struct memoryHTBlock **b;
162 if (!(mht && (ht = mht->ht)))
163 db_panic("some ht called with bad mht");
164 if (ht->length || mht->blocks)
165 db_panic("previous table still allocated");
167 len = ntohl(ht->entries) * 2; /* allow room to grow */
168 nb = (len + nHTBuckets - 1) / nHTBuckets;
169 mnb = ht_minHBlocks(mht);
171 nb = mnb; /* use minimum */
172 len = nb * nHTBuckets; /* new hash table length */
174 mht->size = nb * sizeof(struct memoryHTBlock *);
175 b = mht->blocks = calloc(1, mht->size);
177 for (i = 0; i < nb; i++) {
178 b[i] = (struct memoryHTBlock *)malloc(sizeof(struct memoryHTBlock));
179 code = AllocBlock(ut, (struct block *)&b[i]->b, &b[i]->a);
184 b[i]->b.h.type = hashTable_BLOCK;
186 /* thread the blocks */
188 b[i - 1]->b.h.next = htonl(b[i]->a);
190 for (i = 0; i < nb; i++) {
192 dbwrite(ut, b[i]->a, (char *)&b[i]->b,
193 sizeof(struct htBlock) + (nHTBuckets -
194 NhtBucketS) * sizeof(dbadr));
198 if ((code = set_word_addr(ut, 0, &db.h, &ht->table, htonl(b[0]->a))))
202 if ((code = set_word_addr(ut, 0, &db.h, plen, htonl(len))))
209 ht_FreeTable(struct ubik_trans *ut, struct memoryHashTable *mht)
211 struct hashTable *ht = NULL;
213 struct blockHeader bh;
215 afs_int32 *plen, *pprog;
217 if (!(mht && (ht = mht->ht)))
218 db_panic("some ht called with bad mht");
219 if (ht->oldLength == 0)
220 db_panic("no table to free");
222 ht_ResetT(&mht->oldBlocks, &mht->oldSize, 0);
224 for (a = ntohl(ht->oldTable); a; a = na) {
225 if (dbread(ut, a, (char *)&bh, sizeof(bh))) {
226 Log("ht_FreeTable: dbread failed\n");
230 if ((code = FreeBlock(ut, &bh, a)))
233 plen = &ht->oldLength;
234 pprog = &ht->progress;
235 if (set_word_addr(ut, 0, &db.h, &ht->oldTable, 0)
236 || set_word_addr(ut, 0, &db.h, plen, 0)
237 || set_word_addr(ut, 0, &db.h, pprog, 0))
239 mht->oldLength = mht->progress = 0;
244 ht_GetTableBlock(struct ubik_trans *ut, struct memoryHashTable *mht,
245 afs_uint32 hash, int old, struct memoryHTBlock **blockP,
248 struct hashTable *ht = NULL;
249 struct memoryHTBlock **b;
251 struct memoryHTBlock ***blocksP;
259 || ((ht = mht->ht) == 0)
261 db_panic("some ht called with bad mht");
267 if ((length = mht->oldLength) == 0)
268 return 0; /* no entries */
270 if (hi < mht->progress)
271 return 0; /* no such entry */
272 blocksP = &mht->oldBlocks;
273 sizeP = &mht->oldSize;
275 if ((length = mht->length) == 0)
276 return 0; /* no entries */
278 blocksP = &mht->blocks;
282 bi = hi / nHTBuckets; /* block index */
283 *boP = hi - bi * nHTBuckets; /* block offset ptr */
286 *sizeP = ht_TableSize(length);
287 *blocksP = calloc(1, *sizeP);
289 n = *sizeP / sizeof(struct memoryHTBlock *);
291 db_panic("table size inconsistent");
294 /* find an allocated block or the beginning of the block array */
295 for (i = bi; (i > 0) && (b[i] == 0); i--);
299 if (i == 0) { /* the first block is found from the hashTable */
300 ta = ntohl(old ? ht->oldTable : ht->table);
302 db_panic("non-zero length, but no table");
304 /* else ta is set from last time around loop */
306 (struct memoryHTBlock *)malloc(sizeof(struct memoryHTBlock));
312 if (dbread(ut, b[i]->a, (char *)&b[i]->b, sizeof(struct htBlock)))
319 /* printf("ht_GetTableBlock: hash %d block %d offset %d\n",
320 * hash, *blockP, *boP); */
324 ta = ntohl(b[i++]->b.h.next); /* get next ptr from current block */
329 * Decide when to push the current hash table to the old hash table.
330 * The entries in the old hash table are VALID, and are slowly hashed
331 * into the current table.
335 ht_MaybeAdjust(struct ubik_trans *ut, struct memoryHashTable *mht)
337 struct hashTable *ht = mht->ht;
338 int numberEntries = ntohl(ht->entries);
340 /* old hash table must be empty */
341 if (mht->oldLength != 0)
345 * It costs a lot to grow and shrink the hash table. Therefore, we will not
346 * shrink the hash table (only grow it). If the table is more than 2 entries per
347 * chain (average) we need to grow: push the entries to the old hash table.
350 * || ((mht->length > nHTBuckets) && (numberEntries*8 < mht->length))
353 /* Only grow a hash table if the number of entries is twice the
354 * number of hash length and is less than 20,450 (20 hash blocks). This
355 * means that the volname hash table will not grow (its initial
356 * hashtable size contains 30,600 buckets). Earlier revisions of
357 * the buserver have the initial size at 510 and 5,100 buckets -
358 * in which case we do want to grow it). We don't grow anything larger
359 * than 20,450 entries because it's expensive to re-hash everything.
361 if ((numberEntries > mht->length * 2) && (numberEntries < 20450)) { /* push current hash table to old hash table */
362 ht->oldLength = ht->length;
363 ht->oldTable = ht->table;
368 (ut, ((char *)ht - (char *)&db.h), (char *)ht, sizeof(*ht)))
372 LogDebug(2, "ht_MaybeAdjust: push ht to old\n");
378 ht_LookupBucket(struct ubik_trans *ut, struct memoryHashTable *mht,
379 afs_uint32 hash, int old)
381 struct memoryHTBlock *block;
385 if ((old ? mht->oldLength : mht->length) == 0)
387 code = ht_GetTableBlock(ut, mht, hash, old, &block, &bo);
388 if (code || (block == 0))
390 return ntohl(block->b.bucket[bo]);
393 /* This function is not too bad, for small hash tables, but suffers, I think,
394 * from insufficient mixing of the hash information. */
397 Old2StringHashFunction(unsigned char *str)
399 afs_uint32 hash = 1000003; /* big prime to make "" hash nicely */
401 hash = (hash << 1) + (hash >> 31) + *str++;
405 /* This was actually a coding error, and produces dreadful results. The
406 * problem is that the hash needs to be mixed up not the incoming character. */
409 Old3StringHashFunction(unsigned char *str)
411 afs_uint32 hash = 1000003; /* big prime to make "" hash nicely */
413 hash += (*str++) * 0x072a51a4;
417 /* This function is pretty good. Its main problem is that the low two bits of
418 * the hash multiplier are zero which tends to shift information too far left.
419 * It behaves especially badly for hash tables whose size is a power of two. */
422 Old4StringHashFunction(unsigned char *str)
424 afs_uint32 hash = 1000003; /* big prime to make "" hash nicely */
426 hash = (*str++) + hash * 0x072a51a4;
430 /* While this is good for a hash table with 500 buckets it is nearly as bad as
431 * #3 with a hash table as big as 8200. */
434 Old5StringHashFunction(unsigned char *str)
436 afs_uint32 hash = 1000003; /* big prime to make "" hash nicely */
442 /* This was an attempt to produce a hash function with the smallest and
443 * simplest mixing multiplier. This is only a little worse than the real one,
444 * and the difference seems to be smaller with larger hash tables. It behaves
445 * better than the random hash function. */
448 Old6StringHashFunction(unsigned char *str)
450 afs_uint32 hash = 1000003; /* big prime to make "" hash nicely */
452 hash = hash * 0x81 + (*str++);
456 /* This actually seems to be little better then the real one. Having the same
457 * number of bits but only 5 bits apart seems to produce worse results but
458 * having the bits spanning the same range farther apart also doesn't do as
459 * well. All these differences are fairly small, however. */
462 Old7StringHashFunction(unsigned char *str)
464 afs_uint32 hash = 1000003; /* big prime to make "" hash nicely */
466 hash = hash * 0x42108421 + (*str++);
470 /* This function tries to provide some non-linearity by providing some feedback
471 * from higher-order bits in the word. It also uses shifts instead of
472 * multiplies, which may be faster on some architectures. */
475 Old8StringHashFunction(unsigned char *str)
477 afs_uint32 hash = 1000003; /* big prime to make "" hash nicely */
480 hash + (hash << 7) + (hash << 14) + (hash << 21) + (hash << 28) +
481 (hash >> 17) + *str++;
485 /* This is the result of the above search for good hash functions. It seems
486 * that the choice of multipliers is somewhat arbitrary but has several
487 * constraints. It shouldn't have too many or too few one bits and should be
488 * odd. It behaves beeter than the random hash function. */
491 StringHashFunction(unsigned char *str)
493 afs_uint32 hash = 1000003; /* big prime to make "" hash nicely */
494 /* The multiplicative constant should be odd and have a goodly number of
497 hash = (*str++) + hash * 0x10204081;
502 IdHashFunction(afs_uint32 id)
511 /* The minimum hash table blocks to allocate. Each block contains 510
512 * buckets. They hash table grows when the number of entries reaches
513 * twice the number of buckets.
516 ht_minHBlocks(struct memoryHashTable *mht)
520 switch (ntohl(mht->ht->functionType)) {
521 case HT_dumpIden_FUNCTION:
522 case HT_dumpName_FUNCTION: /* hash table able to handle (befor it grows) ... */
523 retval = 2; /* 1,020 dump entries */
526 case HT_tapeName_FUNCTION:
527 retval = 4; /* 2,040 tape entries */
530 case HT_volName_FUNCTION:
531 retval = 60; /* 61,200 volInfo entries (with different names) */
535 db_panic("Illegal hash function type");
536 retval = -1; /* not reached */
542 ht_HashEntry(struct memoryHashTable *mht,
543 char *e) /* entry's address (in b) */
545 int type = ntohl(mht->ht->functionType);
549 case HT_dumpIden_FUNCTION:
550 retval = IdHashFunction(ntohl(((struct dump *)e)->id));
551 LogDebug(5, "HashEntry: dumpid returns %d\n", retval);
554 case HT_dumpName_FUNCTION:
555 retval = StringHashFunction((unsigned char *)((struct dump *)e)->dumpName);
556 LogDebug(5, "HashEntry: dumpname returns %d\n", retval);
559 case HT_tapeName_FUNCTION:
560 retval = StringHashFunction((unsigned char *)((struct tape *)e)->name);
561 LogDebug(5, "HashEntry: tapename returns %d\n", retval);
564 case HT_volName_FUNCTION:
565 retval = StringHashFunction((unsigned char *)((struct volInfo *)e)->name);
566 LogDebug(5, "HashEntry: volname returns %d\n", retval);
570 db_panic("illegal hash function");
571 retval = -1; /* not reached */
579 * returns a ptr to the memory hash table for the specified hash
583 struct memoryHashTable *
584 ht_GetType(int type, int *e_sizeP)
586 struct memoryHashTable *mht;
588 if ((type <= 0) || (type > HT_MAX_FUNCTION))
592 *e_sizeP = sizeFunctions[type];
594 case HT_dumpIden_FUNCTION:
598 case HT_dumpName_FUNCTION:
602 case HT_tapeName_FUNCTION:
606 case HT_volName_FUNCTION:
613 if (ntohl(mht->ht->functionType) != type)
614 db_panic("ht types don't match");
619 ht_KeyMatch(int type, char *key, char *e)
622 case HT_dumpIden_FUNCTION:
623 return *(dumpId *) key == ntohl(((struct dump *)e)->id);
624 case HT_dumpName_FUNCTION:
625 return strcmp(key, ((struct dump *)e)->dumpName) == 0;
626 case HT_tapeName_FUNCTION:
627 return strcmp(key, ((struct tape *)e)->name) == 0;
628 case HT_volName_FUNCTION:
629 return strcmp(key, ((struct volInfo *)e)->name) == 0;
632 db_panic("illegal hash function");
640 * ut - ubik transaction
641 * mht - memory hash table ptr
642 * key - hash and lookup key
644 * eaP - dbaddr of entry found or zero if failed
645 * e - contents of located entry
649 ht_LookupEntry(struct ubik_trans *ut,
650 struct memoryHashTable *mht,
651 void *key, /* pointer to lookup key to match */
652 dbadr *eaP, /* db addr of entry found or zero */
653 void *e) /* contents of located entry */
655 struct hashTable *ht = NULL;
662 if (!key || !eaP || !e)
663 db_panic("null ptrs passed to LookupEntry");
664 if (!(mht && (ht = mht->ht)))
665 db_panic("some ht called with bad mht");
667 *eaP = 0; /* initialize not-found indicator */
669 type = ntohl(ht->functionType);
670 e_size = sizeFunctions[type];
671 if (type == HT_dumpIden_FUNCTION)
672 hash = IdHashFunction(*(dumpId *) key);
674 hash = StringHashFunction(key);
676 for (old = 0;; old++) {
677 a = ht_LookupBucket(ut, mht, hash, old);
679 if (dbread(ut, a, e, e_size))
681 if (ht_KeyMatch(type, key, e)) {
685 a = ntohl(*(dbadr *) ((char *)e + mht->threadOffset));
694 * opQuota - max # of items to move
696 * opQuota - adjusted to reflect # of moves
700 ht_HashInList(struct ubik_trans *ut, struct memoryHashTable *mht,
701 int *opQuota, struct memoryHTBlock *block, int blockOffset)
703 struct hashTable *ht = mht->ht;
707 char e[sizeof(struct block)]; /* unnecessarily conservative */
708 int e_size = sizeFunctions[ntohl(ht->functionType)];
710 if (mht->length == 0) {
711 if ((code = ht_AllocTable(ut, mht))) {
712 Log("ht_HashInList: ht_AllocTable failed\n");
717 listA = ntohl(block->b.bucket[blockOffset]);
720 Log("ht_HashInList: expecting non-zero bucket\n");
724 for (ea = listA; ea; ea = next_ea) { /*f */
726 LogDebug(3, "ht_HashInList: move entry at %d, type %d\n", ea,
727 ntohl(mht->ht->functionType));
729 if (dbread(ut, ea, e, e_size))
732 /* LogNetDump((struct dump *) e); */
734 /* get the address of the next item on the list */
735 next_ea = ntohl(*(dbadr *) (e + mht->threadOffset));
737 /* write the link into the bucket */
739 set_word_addr(ut, block->a, &block->b,
740 &block->b.bucket[blockOffset], htonl(next_ea));
742 Log("ht_HashInList: bucket update failed\n");
747 struct memoryHTBlock *block;
751 /* get the hash value */
752 hash = ht_HashEntry(mht, e) % mht->length;
753 LogDebug(4, "ht_HashInList: moved to %d\n", hash);
755 /* get the new hash table block */
756 code = ht_GetTableBlock(ut, mht, hash, 0 /*old */ , &block, &bo);
758 Log("ht_HashInList: ht_GetTableBlock failed\n");
762 Log("ht_HashInList: ht_GetTableBlock returned 0\n");
763 return BUDB_INTERNALERROR;
766 /* Chain entry at front of bucket;
767 * first threadOffset of entry = bucket
768 * then bucket = addr of entry
771 (ut, ea, e, mht->threadOffset, block->b.bucket[bo])
772 || set_word_addr(ut, block->a, &block->b,
773 &block->b.bucket[bo], htonl(ea)))
777 if (--(*opQuota) == 0)
785 * The hash table is needs to be re-sized. Move entries from the old
790 ht_MoveEntries(struct ubik_trans *ut, struct memoryHashTable *mht)
792 struct memoryHTBlock *block;
799 if (mht->oldLength == 0)
802 LogDebug(3, "ht_MoveEntries:\n");
803 /* we assume here that the hash function will map numbers smaller than the
804 * size of the hash table straight through to hash table indexes.
806 hash = mht->progress;
808 /* get hash table block ? */
809 code = ht_GetTableBlock(ut, mht, hash, 1 /*old */ , &block, &bo);
814 return BUDB_INTERNALERROR;
816 count = 10; /* max. # entries to move */
819 if (block->b.bucket[bo]) {
820 code = ht_HashInList(ut, mht, &count, block, bo);
822 Log("ht_MoveEntries: ht_HashInList failed\n");
827 if (block->b.bucket[bo] == 0) {
828 /* this bucket is now empty */
832 /* don't exceed the quota of items to be moved */
836 } while (++bo < nHTBuckets);
838 if (mht->progress >= mht->oldLength)
839 return (ht_FreeTable(ut, mht));
841 pprog = &mht->ht->progress;
842 if (set_word_addr(ut, 0, &db.h, pprog, htonl(mht->progress))) {
843 Log("ht_MoveEntries: progress set failed\n");
852 ht_MoveEntries(struct ubik_trans *ut, struct memoryHashTable *mht)
856 struct memoryHTBlock *block;
859 if (mht->oldLength == 0)
862 LogDebug(3, "ht_MoveEntries:\n");
863 /* we assume here that the hash function will map numbers smaller than the
864 * size of the hash table straight through to hash table indexes.
866 hash = mht->progress;
868 /* get hash table block ? */
869 code = ht_GetTableBlock(ut, mht, hash, 1 /*old */ , &block, &bo);
874 return BUDB_INTERNALERROR;
878 if (block->b.bucket[bo]) {
879 code = ht_HashInList(ut, mht, ntohl(block->b.bucket[bo]));
881 Log("ht_MoveEntries: ht_HashInList failed\n");
885 set_word_addr(ut, block->a, &block->b, &block->b.bucket[bo],
888 Log("ht_MoveEntries: clear old entry failed\n");
893 } while (++bo < nHTBuckets);
895 if (mht->progress >= mht->oldLength)
896 return (ht_FreeTable(ut, mht));
898 if (set_word_addr(ut, 0, &db.h, &mht->ht->progress, htonl(mht->progress))) {
899 Log("ht_MoveEntries: progress set failed\n");
907 ht_HashIn(struct ubik_trans *ut,
908 struct memoryHashTable *mht,
909 dbadr ea, /* block db address */
910 void *e) /* entry's address (in b) */
912 struct hashTable *ht = NULL;
914 struct memoryHTBlock *block;
919 if (!(mht && (ht = mht->ht)))
920 db_panic("some ht called with bad mht");
922 if ((code = ht_MaybeAdjust(ut, mht)))
924 if (mht->length == 0)
925 if ((code = ht_AllocTable(ut, mht)))
928 hash = ht_HashEntry(mht, e);
929 code = ht_GetTableBlock(ut, mht, hash, 0 /*old */ , &block, &bo);
933 return BUDB_INTERNALERROR;
935 code = set_word_offset(ut, ea, e, mht->threadOffset, block->b.bucket[bo]);
938 LogDebug(5, "Hashin: set %d to %d\n", mht->threadOffset,
939 block->b.bucket[bo]);
942 set_word_addr(ut, block->a, &block->b, &block->b.bucket[bo],
946 LogDebug(5, "Hashin: set %"AFS_PTR_FMT" to %d\n",
947 &block->b.bucket[bo], htonl(ea));
949 pentries = &ht->entries;
951 set_word_addr(ut, 0, &db.h, pentries,
952 htonl(ntohl(ht->entries) + 1));
956 return ht_MoveEntries(ut, mht);
959 /* RemoveFromList - generic procedure to delete an entry from a list given its
960 * head and thread offset. Only a single long is modified by this routine.
961 * The head pointer is modified, in place, using set_word_addr if the entry is
962 * at the head of the list, otherwise only the thread of the previous entry is
963 * modified. The entry pointer is only used to calculate the thread offset,
964 * but is not otherwise used. */
967 RemoveFromList(struct ubik_trans *ut,
968 dbadr ea, /* db addr of head structure */
969 void *e, /* head structure */
970 dbadr *head, /* address of head pointer */
971 dbadr ta, /* db addr of strucure to be removed */
972 void *t, /* structure being removed */
973 dbadr *thread) /* pointer to thread pointer */
976 int threadOffset = ((char *)thread - (char *)t);
977 dbadr next_a; /* db addr of next element in list */
978 dbadr loop_a; /* db addr of current list element */
981 return -1; /* empty list: not found */
982 next_a = ntohl(*head); /* start at head of list */
983 if (next_a == ta) { /* remove from head of list */
984 code = set_word_addr(ut, ea, e, head, *thread);
990 dbread(ut, loop_a + threadOffset, (char *)&next_a, sizeof(dbadr));
994 return -1; /* end of list: not found */
995 } while (ta != (next_a = ntohl(next_a)));
996 code = dbwrite(ut, loop_a + threadOffset, (char *)thread, sizeof(dbadr));
1001 ht_HashOutT(struct ubik_trans *ut, struct memoryHashTable *mht,
1002 afs_uint32 hash, dbadr ea, char *e, int old)
1004 struct memoryHTBlock *block;
1007 afs_int32 *pentries;
1009 if ((old ? mht->oldLength : mht->length) == 0)
1011 code = ht_GetTableBlock(ut, mht, hash, old, &block, &bo);
1014 if ((block == 0) || (block->b.bucket[bo] == 0))
1018 RemoveFromList(ut, block->a, (char *)&block->b, &block->b.bucket[bo],
1019 ea, e, (dbadr *) (e + mht->threadOffset));
1024 unthread_ea = *(afs_int32 *) ((char *)e + mht->threadOffset);
1025 if (block->b.bucket[bo] == net_ea) {
1027 (ut, block->a, &block->b, &block->b.bucket[bo], unthread_ea))
1031 loop_a = ntohl(block->b.bucket[bo]);
1034 (ut, loop_a + mht->threadOffset, (char *)&next_loop_a,
1037 if (next_loop_a == 0)
1038 return -1; /* not found */
1039 if (net_ea == next_loop_a) {
1041 (ut, loop_a + mht->threadOffset, (char *)&unthread_ea,
1046 loop_a = ntohl(next_loop_a);
1050 pentries = &mht->ht->entries;
1052 (ut, 0, &db.h, pentries, htonl(ntohl(mht->ht->entries) - 1)))
1058 ht_HashOut(struct ubik_trans *ut, struct memoryHashTable *mht, dbadr ea,
1065 db_panic("some ht called with bad mht");
1066 hash = ht_HashEntry(mht, e);
1067 if (mht->oldLength) {
1068 code = ht_HashOutT(ut, mht, hash, ea, e, 1 /*old */ );
1071 else if (code != -1)
1074 if (mht->length == 0) /* not found */
1075 ERROR(BUDB_INTERNALERROR);
1076 code = ht_HashOutT(ut, mht, hash, ea, e, 0 /*old */ );
1082 code = ht_MoveEntries(ut, mht);
1085 code = ht_MaybeAdjust(ut, mht);
1093 /* generic hash table traversal routines */
1097 scanHashTableBlock(struct ubik_trans *ut,
1098 struct memoryHashTable *mhtPtr,
1099 struct htBlock *htBlockPtr,
1101 afs_int32 length, /* size of whole hash table */
1102 int index, /* base index of this block */
1103 int (*selectFn) (dbadr, void *, void *),
1104 int (*operationFn) (dbadr, void *, void *),
1107 int type; /* hash table type */
1108 int entrySize; /* hashed entry size */
1110 char entry[sizeof(struct block)];
1111 dbadr entryAddr, nextEntryAddr;
1115 type = ntohl(mhtPtr->ht->functionType);
1116 entrySize = sizeFunctions[type];
1118 /* step through this hash table block, being careful to stop
1119 * before the end of the overall hash table
1122 for (i = 0; (i < nHTBuckets) && (index < length); i++, index++) { /*f */
1124 nextEntryAddr = ntohl(htBlockPtr->bucket[i]);
1126 /* if this is the old hash table, all entries below the progress mark
1127 * should have been moved to the new hash table
1129 if (old && (index < mhtPtr->progress) && nextEntryAddr)
1130 return BUDB_INTERNALERROR;
1132 /* now walk down the chain of each bucket */
1133 while (nextEntryAddr) { /*w */
1135 entryAddr = nextEntryAddr;
1136 if (dbread(ut, entryAddr, &entry[0], entrySize))
1137 return (BUDB_INTERNALERROR);
1139 if ((*selectFn) (entryAddr, &entry[0], rockPtr)) {
1140 (*operationFn) (entryAddr, &entry[0], rockPtr);
1144 ntohl(*((dbadr *) (entry + mhtPtr->threadOffset)));
1153 scanHashTable(struct ubik_trans *ut, struct memoryHashTable *mhtPtr,
1154 int (*selectFn) (dbadr, void *, void *),
1155 int (*operationFn) (dbadr, void *, void *),
1158 struct htBlock hashTableBlock;
1159 dbadr tableAddr; /* disk addr of hash block */
1160 int tableLength; /* # entries */
1161 int blockLength; /* # blocks */
1167 extern int nHTBuckets; /* # buckets in a hash table */
1169 for (old = 0; old <= 1; old++) { /*fo */
1171 /* check the old hash table */
1172 tableLength = mhtPtr->oldLength;
1173 if (tableLength == 0)
1174 continue; /* nothing to do */
1176 tableAddr = ntohl(mhtPtr->ht->oldTable);
1178 /* check current hash table */
1179 tableLength = mhtPtr->length;
1180 if (tableLength == 0)
1181 continue; /* nothing to do */
1183 tableAddr = ntohl(mhtPtr->ht->table);
1186 blockLength = (tableLength - 1) / nHTBuckets;
1189 /* follow the hash chain */
1190 for (i = 0; i <= blockLength; i++) { /*fi */
1191 /* chain too short */
1193 ERROR(BUDB_DATABASEINCONSISTENT);
1196 dbread(ut, tableAddr, &hashTableBlock,
1197 sizeof(hashTableBlock));
1202 scanHashTableBlock(ut, mhtPtr, &hashTableBlock, old,
1203 tableLength, hashIndex, selectFn,
1204 operationFn, rockPtr);
1208 hashIndex += nHTBuckets;
1209 tableAddr = ntohl(hashTableBlock.h.next);