/*
* assign_func_result_transient_type
* assign typmod if the result of function is transient type.
*
*/
void
assign_func_result_transient_type(Oid funcid)
{
HeapTuple tp;
Form_pg_proc procform;
TupleDesc tupdesc;
cqContext *pcqCtx;
pcqCtx = caql_beginscan(
NULL,
cql("SELECT * FROM pg_proc "
" WHERE oid = :1 ",
ObjectIdGetDatum(funcid)));
tp = caql_getnext(pcqCtx);
caql_endscan(pcqCtx);
if (!HeapTupleIsValid(tp))
elog(ERROR, "cache lookup failed for function %u", funcid);
procform = (Form_pg_proc) GETSTRUCT(tp);
tupdesc = build_function_result_tupdesc_t(tp);
if (tupdesc == NULL)
return;
if (resolve_polymorphic_tupdesc(tupdesc,
&procform->proargtypes,
NULL))
{
if (tupdesc->tdtypeid == RECORDOID &&
tupdesc->tdtypmod < 0)
assign_record_type_typmod(tupdesc);
}
}
HeapTupleHeader
SPI_returntuple(HeapTuple tuple, TupleDesc tupdesc)
{
MemoryContext oldcxt = NULL;
HeapTupleHeader dtup;
if (tuple == NULL || tupdesc == NULL)
{
SPI_result = SPI_ERROR_ARGUMENT;
return NULL;
}
/* For RECORD results, make sure a typmod has been assigned */
if (tupdesc->tdtypeid == RECORDOID &&
tupdesc->tdtypmod < 0)
assign_record_type_typmod(tupdesc);
if (_SPI_curid + 1 == _SPI_connected) /* connected */
{
if (_SPI_current != &(_SPI_stack[_SPI_curid + 1]))
elog(ERROR, "SPI stack corrupted");
oldcxt = MemoryContextSwitchTo(_SPI_current->savedcxt);
}
dtup = (HeapTupleHeader) palloc(tuple->t_len);
memcpy((char *) dtup, (char *) tuple->t_data, tuple->t_len);
HeapTupleHeaderSetDatumLength(dtup, tuple->t_len);
HeapTupleHeaderSetTypeId(dtup, tupdesc->tdtypeid);
HeapTupleHeaderSetTypMod(dtup, tupdesc->tdtypmod);
if (oldcxt)
MemoryContextSwitchTo(oldcxt);
return dtup;
}
/*
* internal_get_result_type -- workhorse code implementing all the above
*
* funcid must always be supplied. call_expr and rsinfo can be NULL if not
* available. We will return TYPEFUNC_RECORD, and store NULL into
* *resultTupleDesc, if we cannot deduce the complete result rowtype from
* the available information.
*/
static TypeFuncClass
internal_get_result_type(Oid funcid,
Node *call_expr,
ReturnSetInfo *rsinfo,
Oid *resultTypeId,
TupleDesc *resultTupleDesc)
{
TypeFuncClass result;
HeapTuple tp;
Form_pg_proc procform;
Oid rettype;
TupleDesc tupdesc;
/* First fetch the function's pg_proc row to inspect its rettype */
tp = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
if (!HeapTupleIsValid(tp))
elog(ERROR, "cache lookup failed for function %u", funcid);
procform = (Form_pg_proc) GETSTRUCT(tp);
rettype = procform->prorettype;
/* Check for OUT parameters defining a RECORD result */
tupdesc = build_function_result_tupdesc_t(tp);
if (tupdesc)
{
/*
* It has OUT parameters, so it's basically like a regular composite
* type, except we have to be able to resolve any polymorphic OUT
* parameters.
*/
if (resultTypeId)
*resultTypeId = rettype;
if (resolve_polymorphic_tupdesc(tupdesc,
&procform->proargtypes,
call_expr))
{
if (tupdesc->tdtypeid == RECORDOID &&
tupdesc->tdtypmod < 0)
assign_record_type_typmod(tupdesc);
if (resultTupleDesc)
*resultTupleDesc = tupdesc;
result = TYPEFUNC_COMPOSITE;
}
else
{
if (resultTupleDesc)
*resultTupleDesc = NULL;
result = TYPEFUNC_RECORD;
}
ReleaseSysCache(tp);
return result;
}
/*
* If scalar polymorphic result, try to resolve it.
*/
if (IsPolymorphicType(rettype))
{
Oid newrettype = exprType(call_expr);
if (newrettype == InvalidOid) /* this probably should not happen */
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("could not determine actual result type for function \"%s\" declared to return type %s",
NameStr(procform->proname),
format_type_be(rettype))));
rettype = newrettype;
}
if (resultTypeId)
*resultTypeId = rettype;
if (resultTupleDesc)
*resultTupleDesc = NULL; /* default result */
/* Classify the result type */
result = get_type_func_class(rettype);
switch (result)
{
case TYPEFUNC_COMPOSITE:
if (resultTupleDesc)
*resultTupleDesc = lookup_rowtype_tupdesc_copy(rettype, -1);
/* Named composite types can't have any polymorphic columns */
break;
case TYPEFUNC_SCALAR:
break;
case TYPEFUNC_RECORD:
/* We must get the tupledesc from call context */
if (rsinfo && IsA(rsinfo, ReturnSetInfo) &&
rsinfo->expectedDesc != NULL)
{
result = TYPEFUNC_COMPOSITE;
if (resultTupleDesc)
*resultTupleDesc = rsinfo->expectedDesc;
/* Assume no polymorphic columns here, either */
}
break;
default:
break;
}
ReleaseSysCache(tp);
return result;
}
/* ----------------------------------------------------------------
* ExecInitFunctionScan
* ----------------------------------------------------------------
*/
FunctionScanState *
ExecInitFunctionScan(FunctionScan *node, EState *estate)
{
FunctionScanState *scanstate;
RangeTblEntry *rte;
Oid funcrettype;
TypeFuncClass functypclass;
TupleDesc tupdesc = NULL;
/*
* FunctionScan should not have any children.
*/
Assert(outerPlan(node) == NULL);
Assert(innerPlan(node) == NULL);
/*
* create new ScanState for node
*/
scanstate = makeNode(FunctionScanState);
scanstate->ss.ps.plan = (Plan *) node;
scanstate->ss.ps.state = estate;
/*
* Miscellaneous initialization
*
* create expression context for node
*/
ExecAssignExprContext(estate, &scanstate->ss.ps);
#define FUNCTIONSCAN_NSLOTS 2
/*
* tuple table initialization
*/
ExecInitResultTupleSlot(estate, &scanstate->ss.ps);
ExecInitScanTupleSlot(estate, &scanstate->ss);
/*
* initialize child expressions
*/
scanstate->ss.ps.targetlist = (List *)
ExecInitExpr((Expr *) node->scan.plan.targetlist,
(PlanState *) scanstate);
scanstate->ss.ps.qual = (List *)
ExecInitExpr((Expr *) node->scan.plan.qual,
(PlanState *) scanstate);
/*
* get info about function
*/
rte = rt_fetch(node->scan.scanrelid, estate->es_range_table);
Assert(rte->rtekind == RTE_FUNCTION);
funcrettype = exprType(rte->funcexpr);
/*
* Now determine if the function returns a simple or composite type,
* and build an appropriate tupdesc.
*/
functypclass = get_type_func_class(funcrettype);
if (functypclass == TYPEFUNC_COMPOSITE)
{
/* Composite data type, e.g. a table's row type */
tupdesc = CreateTupleDescCopy(lookup_rowtype_tupdesc(funcrettype, -1));
}
else if (functypclass == TYPEFUNC_SCALAR)
{
/* Base data type, i.e. scalar */
char *attname = strVal(linitial(rte->eref->colnames));
tupdesc = CreateTemplateTupleDesc(1, false);
TupleDescInitEntry(tupdesc,
(AttrNumber) 1,
attname,
funcrettype,
-1,
0);
}
else if (functypclass == TYPEFUNC_RECORD)
{
tupdesc = BuildDescForRelation(rte->coldeflist);
}
else
{
/* crummy error message, but parser should have caught this */
elog(ERROR, "function in FROM has unsupported return type");
}
/*
* For RECORD results, make sure a typmod has been assigned. (The
* function should do this for itself, but let's cover things in case
* it doesn't.)
*/
if (tupdesc->tdtypeid == RECORDOID && tupdesc->tdtypmod < 0)
assign_record_type_typmod(tupdesc);
scanstate->tupdesc = tupdesc;
ExecSetSlotDescriptor(scanstate->ss.ss_ScanTupleSlot,
tupdesc, false);
/*
* Other node-specific setup
*/
scanstate->tuplestorestate = NULL;
scanstate->funcexpr = ExecInitExpr((Expr *) rte->funcexpr,
(PlanState *) scanstate);
scanstate->ss.ps.ps_TupFromTlist = false;
/*
* Initialize result tuple type and projection info.
*/
ExecAssignResultTypeFromTL(&scanstate->ss.ps);
ExecAssignProjectionInfo(&scanstate->ss.ps);
return scanstate;
}
