From a933ee38bbb8dffbc48a3363a94ff6f2a9f7964d Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 16 Nov 2000 22:30:52 +0000 Subject: Change SearchSysCache coding conventions so that a reference count is maintained for each cache entry. A cache entry will not be freed until the matching ReleaseSysCache call has been executed. This eliminates worries about cache entries getting dropped while still in use. See my posting to pg-hackers of even date for more info. --- src/backend/parser/parse_node.c | 52 ++++++++++++++++++++--------------------- 1 file changed, 25 insertions(+), 27 deletions(-) (limited to 'src/backend/parser/parse_node.c') diff --git a/src/backend/parser/parse_node.c b/src/backend/parser/parse_node.c index d23c5c1e7c7..1d846bd4bba 100644 --- a/src/backend/parser/parse_node.c +++ b/src/backend/parser/parse_node.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/parser/parse_node.c,v 1.48 2000/10/31 10:22:11 petere Exp $ + * $Header: /cvsroot/pgsql/src/backend/parser/parse_node.c,v 1.49 2000/11/16 22:30:28 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -67,7 +67,6 @@ make_operand(char *opname, Oid target_typeId) { Node *result; - Type target_type = typeidType(target_typeId); if (tree != NULL) { @@ -80,15 +79,7 @@ make_operand(char *opname, else { /* otherwise, this is a NULL value */ - Const *con = makeNode(Const); - - con->consttype = target_typeId; - con->constlen = typeLen(target_type); - con->constvalue = (Datum) NULL; - con->constisnull = true; - con->constbyval = typeByVal(target_type); - con->constisset = false; - result = (Node *) con; + result = (Node *) makeNullConst(target_typeId); } return result; @@ -137,7 +128,7 @@ make_op(char *opname, Node *ltree, Node *rtree) /* otherwise, binary operator */ else { - tup = oper(opname, ltypeId, rtypeId, FALSE); + tup = oper(opname, ltypeId, rtypeId, false); opform = (Form_pg_operator) GETSTRUCT(tup); left = make_operand(opname, ltree, ltypeId, opform->oprleft); right = make_operand(opname, rtree, rtypeId, opform->oprright); @@ -159,6 +150,8 @@ make_op(char *opname, Node *ltree, Node *rtree) else result->args = makeList2(left, right); + ReleaseSysCache(tup); + return result; } /* make_op() */ @@ -183,10 +176,10 @@ make_var(ParseState *pstate, RangeTblEntry *rte, int attrno) HeapTuple tp; Form_pg_attribute att_tup; - tp = SearchSysCacheTuple(ATTNUM, - ObjectIdGetDatum(rte->relid), - Int16GetDatum(attrno), - 0, 0); + tp = SearchSysCache(ATTNUM, + ObjectIdGetDatum(rte->relid), + Int16GetDatum(attrno), + 0, 0); /* this shouldn't happen... */ if (!HeapTupleIsValid(tp)) elog(ERROR, "Relation %s does not have attribute %d", @@ -194,6 +187,7 @@ make_var(ParseState *pstate, RangeTblEntry *rte, int attrno) att_tup = (Form_pg_attribute) GETSTRUCT(tp); vartypeid = att_tup->atttypid; type_mod = att_tup->atttypmod; + ReleaseSysCache(tp); } else { @@ -249,7 +243,8 @@ transformArraySubscripts(ParseState *pstate, Oid typearray, typeelement, typeresult; - HeapTuple type_tuple; + HeapTuple type_tuple_array, + type_tuple_element; Form_pg_type type_struct_array, type_struct_element; bool isSlice = forceSlice; @@ -261,13 +256,13 @@ transformArraySubscripts(ParseState *pstate, /* Get the type tuple for the array */ typearray = exprType(arrayBase); - type_tuple = SearchSysCacheTuple(TYPEOID, - ObjectIdGetDatum(typearray), - 0, 0, 0); - if (!HeapTupleIsValid(type_tuple)) + type_tuple_array = SearchSysCache(TYPEOID, + ObjectIdGetDatum(typearray), + 0, 0, 0); + if (!HeapTupleIsValid(type_tuple_array)) elog(ERROR, "transformArraySubscripts: Cache lookup failed for array type %u", typearray); - type_struct_array = (Form_pg_type) GETSTRUCT(type_tuple); + type_struct_array = (Form_pg_type) GETSTRUCT(type_tuple_array); typeelement = type_struct_array->typelem; if (typeelement == InvalidOid) @@ -275,13 +270,13 @@ transformArraySubscripts(ParseState *pstate, NameStr(type_struct_array->typname)); /* Get the type tuple for the array element type */ - type_tuple = SearchSysCacheTuple(TYPEOID, - ObjectIdGetDatum(typeelement), - 0, 0, 0); - if (!HeapTupleIsValid(type_tuple)) + type_tuple_element = SearchSysCache(TYPEOID, + ObjectIdGetDatum(typeelement), + 0, 0, 0); + if (!HeapTupleIsValid(type_tuple_element)) elog(ERROR, "transformArraySubscripts: Cache lookup failed for array element type %u", typeelement); - type_struct_element = (Form_pg_type) GETSTRUCT(type_tuple); + type_struct_element = (Form_pg_type) GETSTRUCT(type_tuple_element); /* * A list containing only single subscripts refers to a single array @@ -398,6 +393,9 @@ transformArraySubscripts(ParseState *pstate, aref->refexpr = arrayBase; aref->refassgnexpr = assignFrom; + ReleaseSysCache(type_tuple_array); + ReleaseSysCache(type_tuple_element); + return aref; } -- cgit v1.2.3