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Reimplement the linked list data structure used throughout the backend.

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In the past, we used a 'Lispy' linked list implementation: a "list" was
merely a pointer to the head node of the list. The problem with that
design is that it makes lappend() and length() linear time. This patch
fixes that problem (and others) by maintaining a count of the list
length and a pointer to the tail node along with each head node pointer.
A "list" is now a pointer to a structure containing some meta-data
about the list; the head and tail pointers in that structure refer
to ListCell structures that maintain the actual linked list of nodes.

The function names of the list API have also been changed to, I hope,
be more logically consistent. By default, the old function names are
still available; they will be disabled-by-default once the rest of
the tree has been updated to use the new API names.
This commit is contained in:
Neil Conway
2004-05-26 04:41:50 +00:00
parent 18d0d10563
commit d0b4399d81
125 changed files with 3639 additions and 3038 deletions
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30
src/backend/catalog/index.c
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@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/catalog/index.c,v 1.231 2004/05/08 19:09:24 tgl Exp $
* $PostgreSQL: pgsql/src/backend/catalog/index.c,v 1.232 2004/05/26 04:41:07 neilc Exp $
*
*
* INTERFACE ROUTINES
@@ -88,7 +88,7 @@ ConstructTupleDescriptor(Relation heapRelation,
Oid *classObjectId)
{
int numatts = indexInfo->ii_NumIndexAttrs;
List *indexprs = indexInfo->ii_Expressions;
ListCell *indexpr_item = list_head(indexInfo->ii_Expressions);
TupleDesc heapTupDesc;
TupleDesc indexTupDesc;
int natts; /* #atts in heap rel --- for error checks */
@@ -165,10 +165,10 @@ ConstructTupleDescriptor(Relation heapRelation,
/* Expressional index */
Node *indexkey;
if (indexprs == NIL) /* shouldn't happen */
if (indexpr_item == NULL) /* shouldn't happen */
elog(ERROR, "too few entries in indexprs list");
indexkey = (Node *) lfirst(indexprs);
indexprs = lnext(indexprs);
indexkey = (Node *) lfirst(indexpr_item);
indexpr_item = lnext(indexpr_item);
/*
* Make the attribute's name "pg_expresssion_nnn" (maybe think
@@ -928,7 +928,7 @@ FormIndexDatum(IndexInfo *indexInfo,
Datum *datum,
char *nullv)
{
List *indexprs;
ListCell *indexpr_item;
int i;
if (indexInfo->ii_Expressions != NIL &&
@@ -941,7 +941,7 @@ FormIndexDatum(IndexInfo *indexInfo,
/* Check caller has set up context correctly */
Assert(GetPerTupleExprContext(estate)->ecxt_scantuple->val == heapTuple);
}
indexprs = indexInfo->ii_ExpressionsState;
indexpr_item = list_head(indexInfo->ii_ExpressionsState);
for (i = 0; i < indexInfo->ii_NumIndexAttrs; i++)
{
@@ -962,19 +962,19 @@ FormIndexDatum(IndexInfo *indexInfo,
/*
* Index expression --- need to evaluate it.
*/
if (indexprs == NIL)
if (indexpr_item == NULL)
elog(ERROR, "wrong number of index expressions");
iDatum = ExecEvalExprSwitchContext((ExprState *) lfirst(indexprs),
iDatum = ExecEvalExprSwitchContext((ExprState *) lfirst(indexpr_item),
GetPerTupleExprContext(estate),
&isNull,
NULL);
indexprs = lnext(indexprs);
indexpr_item = lnext(indexpr_item);
}
datum[i] = iDatum;
nullv[i] = (isNull) ? 'n' : ' ';
}
if (indexprs != NIL)
if (indexpr_item != NULL)
elog(ERROR, "wrong number of index expressions");
}
@@ -1738,8 +1738,8 @@ reindex_relation(Oid relid, bool toast_too)
bool is_pg_class;
bool result;
List *indexIds,
*doneIndexes,
*indexId;
*doneIndexes;
ListCell *indexId;
/*
* Ensure to hold an exclusive lock throughout the transaction. The
@@ -1780,7 +1780,7 @@ reindex_relation(Oid relid, bool toast_too)
/* Reindex all the indexes. */
foreach(indexId, indexIds)
{
Oid indexOid = lfirsto(indexId);
Oid indexOid = lfirst_oid(indexId);
if (is_pg_class)
RelationSetIndexList(rel, doneIndexes);
@@ -1790,7 +1790,7 @@ reindex_relation(Oid relid, bool toast_too)
CommandCounterIncrement();
if (is_pg_class)
doneIndexes = lappendo(doneIndexes, indexOid);
doneIndexes = lappend_oid(doneIndexes, indexOid);
}
if (is_pg_class)