diff options
Diffstat (limited to 'src/backend/access/hash/hashutil.c')
| -rw-r--r-- | src/backend/access/hash/hashutil.c | 60 |
1 files changed, 37 insertions, 23 deletions
diff --git a/src/backend/access/hash/hashutil.c b/src/backend/access/hash/hashutil.c index 83126fccb4..76d9bc5f4e 100644 --- a/src/backend/access/hash/hashutil.c +++ b/src/backend/access/hash/hashutil.c @@ -8,11 +8,10 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/access/hash/hashutil.c,v 1.33 2003/08/04 02:39:57 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/access/hash/hashutil.c,v 1.34 2003/09/02 02:18:38 tgl Exp $ * *------------------------------------------------------------------------- */ - #include "postgres.h" #include "access/genam.h" @@ -20,20 +19,23 @@ #include "access/iqual.h" +/* + * _hash_mkscankey -- build a scan key matching the given indextuple + * + * Note: this is prepared for multiple index columns, but very little + * else in access/hash is ... + */ ScanKey _hash_mkscankey(Relation rel, IndexTuple itup) { ScanKey skey; - TupleDesc itupdesc; - int natts; + TupleDesc itupdesc = RelationGetDescr(rel); + int natts = rel->rd_rel->relnatts; AttrNumber i; Datum arg; FmgrInfo *procinfo; bool isnull; - natts = rel->rd_rel->relnatts; - itupdesc = RelationGetDescr(rel); - skey = (ScanKey) palloc(natts * sizeof(ScanKeyData)); for (i = 0; i < natts; i++) @@ -41,7 +43,7 @@ _hash_mkscankey(Relation rel, IndexTuple itup) arg = index_getattr(itup, i + 1, itupdesc, &isnull); procinfo = index_getprocinfo(rel, i + 1, HASHPROC); ScanKeyEntryInitializeWithInfo(&skey[i], - 0x0, + isnull ? SK_ISNULL : 0x0, (AttrNumber) (i + 1), procinfo, CurrentMemoryContext, @@ -57,18 +59,19 @@ _hash_freeskey(ScanKey skey) pfree(skey); } - +/* + * _hash_checkqual -- does the index tuple satisfy the scan conditions? + */ bool _hash_checkqual(IndexScanDesc scan, IndexTuple itup) { - if (scan->numberOfKeys > 0) - return (index_keytest(itup, - RelationGetDescr(scan->indexRelation), - scan->numberOfKeys, scan->keyData)); - else - return true; + return index_keytest(itup, RelationGetDescr(scan->indexRelation), + scan->numberOfKeys, scan->keyData); } +/* + * _hash_formitem -- construct a hash index entry + */ HashItem _hash_formitem(IndexTuple itup) { @@ -82,17 +85,27 @@ _hash_formitem(IndexTuple itup) (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("hash indexes cannot include null keys"))); - /* make a copy of the index tuple with room for the sequence number */ + /* + * make a copy of the index tuple (XXX do we still need to copy?) + * + * HashItemData used to have more fields than IndexTupleData, but no + * longer... + */ tuplen = IndexTupleSize(itup); nbytes_hitem = tuplen + (sizeof(HashItemData) - sizeof(IndexTupleData)); hitem = (HashItem) palloc(nbytes_hitem); - memmove((char *) &(hitem->hash_itup), (char *) itup, tuplen); + memcpy((char *) &(hitem->hash_itup), (char *) itup, tuplen); return hitem; } +/* + * _hash_call -- given a Datum, call the index's hash procedure + * + * Returns the bucket number that the hash key maps to. + */ Bucket _hash_call(Relation rel, HashMetaPage metap, Datum key) { @@ -103,9 +116,11 @@ _hash_call(Relation rel, HashMetaPage metap, Datum key) /* XXX assumes index has only one attribute */ procinfo = index_getprocinfo(rel, 1, HASHPROC); n = DatumGetUInt32(FunctionCall1(procinfo, key)); + bucket = n & metap->hashm_highmask; if (bucket > metap->hashm_maxbucket) bucket = bucket & metap->hashm_lowmask; + return bucket; } @@ -119,7 +134,7 @@ _hash_log2(uint32 num) limit; limit = 1; - for (i = 0; limit < num; limit = limit << 1, i++) + for (i = 0; limit < num; limit <<= 1, i++) ; return i; } @@ -130,20 +145,19 @@ _hash_log2(uint32 num) void _hash_checkpage(Page page, int flags) { - HashPageOpaque opaque; - +#ifdef USE_ASSERT_CHECKING Assert(page); Assert(((PageHeader) (page))->pd_lower >= SizeOfPageHeaderData); -#if 1 Assert(((PageHeader) (page))->pd_upper <= (BLCKSZ - MAXALIGN(sizeof(HashPageOpaqueData)))); Assert(((PageHeader) (page))->pd_special == (BLCKSZ - MAXALIGN(sizeof(HashPageOpaqueData)))); Assert(PageGetPageSize(page) == BLCKSZ); -#endif if (flags) { - opaque = (HashPageOpaque) PageGetSpecialPointer(page); + HashPageOpaque opaque = (HashPageOpaque) PageGetSpecialPointer(page); + Assert(opaque->hasho_flag & flags); } +#endif /* USE_ASSERT_CHECKING */ } |