Adding upstream version 15.5.upstream/15.5

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2115 insertions, 0 deletions

diff --git a/src/backend/utils/fmgr/funcapi.c b/src/backend/utils/fmgr/funcapi.c
new file mode 100644
index 0000000..31f6662
--- /dev/null
+++ b/src/backend/utils/fmgr/funcapi.c
@@ -0,0 +1,2115 @@
+/*-------------------------------------------------------------------------
+ *
+ * funcapi.c
+ *	  Utility and convenience functions for fmgr functions that return
+ *	  sets and/or composite types, or deal with VARIADIC inputs.
+ *
+ * Copyright (c) 2002-2022, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ *	  src/backend/utils/fmgr/funcapi.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "access/htup_details.h"
+#include "access/relation.h"
+#include "catalog/namespace.h"
+#include "catalog/pg_proc.h"
+#include "catalog/pg_type.h"
+#include "funcapi.h"
+#include "miscadmin.h"
+#include "nodes/nodeFuncs.h"
+#include "utils/array.h"
+#include "utils/builtins.h"
+#include "utils/lsyscache.h"
+#include "utils/memutils.h"
+#include "utils/regproc.h"
+#include "utils/rel.h"
+#include "utils/syscache.h"
+#include "utils/tuplestore.h"
+#include "utils/typcache.h"
+
+
+typedef struct polymorphic_actuals
+{
+	Oid			anyelement_type;	/* anyelement mapping, if known */
+	Oid			anyarray_type;	/* anyarray mapping, if known */
+	Oid			anyrange_type;	/* anyrange mapping, if known */
+	Oid			anymultirange_type; /* anymultirange mapping, if known */
+} polymorphic_actuals;
+
+static void shutdown_MultiFuncCall(Datum arg);
+static TypeFuncClass internal_get_result_type(Oid funcid,
+											  Node *call_expr,
+											  ReturnSetInfo *rsinfo,
+											  Oid *resultTypeId,
+											  TupleDesc *resultTupleDesc);
+static void resolve_anyelement_from_others(polymorphic_actuals *actuals);
+static void resolve_anyarray_from_others(polymorphic_actuals *actuals);
+static void resolve_anyrange_from_others(polymorphic_actuals *actuals);
+static void resolve_anymultirange_from_others(polymorphic_actuals *actuals);
+static bool resolve_polymorphic_tupdesc(TupleDesc tupdesc,
+										oidvector *declared_args,
+										Node *call_expr);
+static TypeFuncClass get_type_func_class(Oid typid, Oid *base_typeid);
+
+
+/*
+ * Compatibility function for v15.
+ */
+void
+SetSingleFuncCall(FunctionCallInfo fcinfo, bits32 flags)
+{
+	InitMaterializedSRF(fcinfo, flags);
+}
+
+/*
+ * InitMaterializedSRF
+ *
+ * Helper function to build the state of a set-returning function used
+ * in the context of a single call with materialize mode.  This code
+ * includes sanity checks on ReturnSetInfo, creates the Tuplestore and
+ * the TupleDesc used with the function and stores them into the
+ * function's ReturnSetInfo.
+ *
+ * "flags" can be set to MAT_SRF_USE_EXPECTED_DESC, to use the tuple
+ * descriptor coming from expectedDesc, which is the tuple descriptor
+ * expected by the caller.  MAT_SRF_BLESS can be set to complete the
+ * information associated to the tuple descriptor, which is necessary
+ * in some cases where the tuple descriptor comes from a transient
+ * RECORD datatype.
+ */
+void
+InitMaterializedSRF(FunctionCallInfo fcinfo, bits32 flags)
+{
+	bool		random_access;
+	ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+	Tuplestorestate *tupstore;
+	MemoryContext old_context,
+				per_query_ctx;
+	TupleDesc	stored_tupdesc;
+
+	/* check to see if caller supports returning a tuplestore */
+	if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("set-valued function called in context that cannot accept a set")));
+	if (!(rsinfo->allowedModes & SFRM_Materialize) ||
+		((flags & MAT_SRF_USE_EXPECTED_DESC) != 0 && rsinfo->expectedDesc == NULL))
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("materialize mode required, but it is not allowed in this context")));
+
+	/*
+	 * Store the tuplestore and the tuple descriptor in ReturnSetInfo.  This
+	 * must be done in the per-query memory context.
+	 */
+	per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
+	old_context = MemoryContextSwitchTo(per_query_ctx);
+
+	/* build a tuple descriptor for our result type */
+	if ((flags & MAT_SRF_USE_EXPECTED_DESC) != 0)
+		stored_tupdesc = CreateTupleDescCopy(rsinfo->expectedDesc);
+	else
+	{
+		if (get_call_result_type(fcinfo, NULL, &stored_tupdesc) != TYPEFUNC_COMPOSITE)
+			elog(ERROR, "return type must be a row type");
+	}
+
+	/* If requested, bless the tuple descriptor */
+	if ((flags & MAT_SRF_BLESS) != 0)
+		BlessTupleDesc(stored_tupdesc);
+
+	random_access = (rsinfo->allowedModes & SFRM_Materialize_Random) != 0;
+
+	tupstore = tuplestore_begin_heap(random_access, false, work_mem);
+	rsinfo->returnMode = SFRM_Materialize;
+	rsinfo->setResult = tupstore;
+	rsinfo->setDesc = stored_tupdesc;
+	MemoryContextSwitchTo(old_context);
+}
+
+
+/*
+ * init_MultiFuncCall
+ * Create an empty FuncCallContext data structure
+ * and do some other basic Multi-function call setup
+ * and error checking
+ */
+FuncCallContext *
+init_MultiFuncCall(PG_FUNCTION_ARGS)
+{
+	FuncCallContext *retval;
+
+	/*
+	 * Bail if we're called in the wrong context
+	 */
+	if (fcinfo->resultinfo == NULL || !IsA(fcinfo->resultinfo, ReturnSetInfo))
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("set-valued function called in context that cannot accept a set")));
+
+	if (fcinfo->flinfo->fn_extra == NULL)
+	{
+		/*
+		 * First call
+		 */
+		ReturnSetInfo *rsi = (ReturnSetInfo *) fcinfo->resultinfo;
+		MemoryContext multi_call_ctx;
+
+		/*
+		 * Create a suitably long-lived context to hold cross-call data
+		 */
+		multi_call_ctx = AllocSetContextCreate(fcinfo->flinfo->fn_mcxt,
+											   "SRF multi-call context",
+											   ALLOCSET_SMALL_SIZES);
+
+		/*
+		 * Allocate suitably long-lived space and zero it
+		 */
+		retval = (FuncCallContext *)
+			MemoryContextAllocZero(multi_call_ctx,
+								   sizeof(FuncCallContext));
+
+		/*
+		 * initialize the elements
+		 */
+		retval->call_cntr = 0;
+		retval->max_calls = 0;
+		retval->user_fctx = NULL;
+		retval->attinmeta = NULL;
+		retval->tuple_desc = NULL;
+		retval->multi_call_memory_ctx = multi_call_ctx;
+
+		/*
+		 * save the pointer for cross-call use
+		 */
+		fcinfo->flinfo->fn_extra = retval;
+
+		/*
+		 * Ensure we will get shut down cleanly if the exprcontext is not run
+		 * to completion.
+		 */
+		RegisterExprContextCallback(rsi->econtext,
+									shutdown_MultiFuncCall,
+									PointerGetDatum(fcinfo->flinfo));
+	}
+	else
+	{
+		/* second and subsequent calls */
+		elog(ERROR, "init_MultiFuncCall cannot be called more than once");
+
+		/* never reached, but keep compiler happy */
+		retval = NULL;
+	}
+
+	return retval;
+}
+
+/*
+ * per_MultiFuncCall
+ *
+ * Do Multi-function per-call setup
+ */
+FuncCallContext *
+per_MultiFuncCall(PG_FUNCTION_ARGS)
+{
+	FuncCallContext *retval = (FuncCallContext *) fcinfo->flinfo->fn_extra;
+
+	return retval;
+}
+
+/*
+ * end_MultiFuncCall
+ * Clean up after init_MultiFuncCall
+ */
+void
+end_MultiFuncCall(PG_FUNCTION_ARGS, FuncCallContext *funcctx)
+{
+	ReturnSetInfo *rsi = (ReturnSetInfo *) fcinfo->resultinfo;
+
+	/* Deregister the shutdown callback */
+	UnregisterExprContextCallback(rsi->econtext,
+								  shutdown_MultiFuncCall,
+								  PointerGetDatum(fcinfo->flinfo));
+
+	/* But use it to do the real work */
+	shutdown_MultiFuncCall(PointerGetDatum(fcinfo->flinfo));
+}
+
+/*
+ * shutdown_MultiFuncCall
+ * Shutdown function to clean up after init_MultiFuncCall
+ */
+static void
+shutdown_MultiFuncCall(Datum arg)
+{
+	FmgrInfo   *flinfo = (FmgrInfo *) DatumGetPointer(arg);
+	FuncCallContext *funcctx = (FuncCallContext *) flinfo->fn_extra;
+
+	/* unbind from flinfo */
+	flinfo->fn_extra = NULL;
+
+	/*
+	 * Delete context that holds all multi-call data, including the
+	 * FuncCallContext itself
+	 */
+	MemoryContextDelete(funcctx->multi_call_memory_ctx);
+}
+
+
+/*
+ * get_call_result_type
+ *		Given a function's call info record, determine the kind of datatype
+ *		it is supposed to return.  If resultTypeId isn't NULL, *resultTypeId
+ *		receives the actual datatype OID (this is mainly useful for scalar
+ *		result types).  If resultTupleDesc isn't NULL, *resultTupleDesc
+ *		receives a pointer to a TupleDesc when the result is of a composite
+ *		type, or NULL when it's a scalar result.
+ *
+ * One hard case that this handles is resolution of actual rowtypes for
+ * functions returning RECORD (from either the function's OUT parameter
+ * list, or a ReturnSetInfo context node).  TYPEFUNC_RECORD is returned
+ * only when we couldn't resolve the actual rowtype for lack of information.
+ *
+ * The other hard case that this handles is resolution of polymorphism.
+ * We will never return polymorphic pseudotypes (ANYELEMENT etc), either
+ * as a scalar result type or as a component of a rowtype.
+ *
+ * This function is relatively expensive --- in a function returning set,
+ * try to call it only the first time through.
+ */
+TypeFuncClass
+get_call_result_type(FunctionCallInfo fcinfo,
+					 Oid *resultTypeId,
+					 TupleDesc *resultTupleDesc)
+{
+	return internal_get_result_type(fcinfo->flinfo->fn_oid,
+									fcinfo->flinfo->fn_expr,
+									(ReturnSetInfo *) fcinfo->resultinfo,
+									resultTypeId,
+									resultTupleDesc);
+}
+
+/*
+ * get_expr_result_type
+ *		As above, but work from a calling expression node tree
+ */
+TypeFuncClass
+get_expr_result_type(Node *expr,
+					 Oid *resultTypeId,
+					 TupleDesc *resultTupleDesc)
+{
+	TypeFuncClass result;
+
+	if (expr && IsA(expr, FuncExpr))
+		result = internal_get_result_type(((FuncExpr *) expr)->funcid,
+										  expr,
+										  NULL,
+										  resultTypeId,
+										  resultTupleDesc);
+	else if (expr && IsA(expr, OpExpr))
+		result = internal_get_result_type(get_opcode(((OpExpr *) expr)->opno),
+										  expr,
+										  NULL,
+										  resultTypeId,
+										  resultTupleDesc);
+	else if (expr && IsA(expr, RowExpr) &&
+			 ((RowExpr *) expr)->row_typeid == RECORDOID)
+	{
+		/* We can resolve the record type by generating the tupdesc directly */
+		RowExpr    *rexpr = (RowExpr *) expr;
+		TupleDesc	tupdesc;
+		AttrNumber	i = 1;
+		ListCell   *lcc,
+				   *lcn;
+
+		tupdesc = CreateTemplateTupleDesc(list_length(rexpr->args));
+		Assert(list_length(rexpr->args) == list_length(rexpr->colnames));
+		forboth(lcc, rexpr->args, lcn, rexpr->colnames)
+		{
+			Node	   *col = (Node *) lfirst(lcc);
+			char	   *colname = strVal(lfirst(lcn));
+
+			TupleDescInitEntry(tupdesc, i,
+							   colname,
+							   exprType(col),
+							   exprTypmod(col),
+							   0);
+			TupleDescInitEntryCollation(tupdesc, i,
+										exprCollation(col));
+			i++;
+		}
+		if (resultTypeId)
+			*resultTypeId = rexpr->row_typeid;
+		if (resultTupleDesc)
+			*resultTupleDesc = BlessTupleDesc(tupdesc);
+		return TYPEFUNC_COMPOSITE;
+	}
+	else if (expr && IsA(expr, Const) &&
+			 ((Const *) expr)->consttype == RECORDOID &&
+			 !((Const *) expr)->constisnull)
+	{
+		/*
+		 * When EXPLAIN'ing some queries with SEARCH/CYCLE clauses, we may
+		 * need to resolve field names of a RECORD-type Const.  The datum
+		 * should contain a typmod that will tell us that.
+		 */
+		HeapTupleHeader rec;
+		Oid			tupType;
+		int32		tupTypmod;
+
+		rec = DatumGetHeapTupleHeader(((Const *) expr)->constvalue);
+		tupType = HeapTupleHeaderGetTypeId(rec);
+		tupTypmod = HeapTupleHeaderGetTypMod(rec);
+		if (resultTypeId)
+			*resultTypeId = tupType;
+		if (tupType != RECORDOID || tupTypmod >= 0)
+		{
+			/* Should be able to look it up */
+			if (resultTupleDesc)
+				*resultTupleDesc = lookup_rowtype_tupdesc_copy(tupType,
+															   tupTypmod);
+			return TYPEFUNC_COMPOSITE;
+		}
+		else
+		{
+			/* This shouldn't really happen ... */
+			if (resultTupleDesc)
+				*resultTupleDesc = NULL;
+			return TYPEFUNC_RECORD;
+		}
+	}
+	else
+	{
+		/* handle as a generic expression; no chance to resolve RECORD */
+		Oid			typid = exprType(expr);
+		Oid			base_typid;
+
+		if (resultTypeId)
+			*resultTypeId = typid;
+		if (resultTupleDesc)
+			*resultTupleDesc = NULL;
+		result = get_type_func_class(typid, &base_typid);
+		if ((result == TYPEFUNC_COMPOSITE ||
+			 result == TYPEFUNC_COMPOSITE_DOMAIN) &&
+			resultTupleDesc)
+			*resultTupleDesc = lookup_rowtype_tupdesc_copy(base_typid, -1);
+	}
+
+	return result;
+}
+
+/*
+ * get_func_result_type
+ *		As above, but work from a function's OID only
+ *
+ * This will not be able to resolve pure-RECORD results nor polymorphism.
+ */
+TypeFuncClass
+get_func_result_type(Oid functionId,
+					 Oid *resultTypeId,
+					 TupleDesc *resultTupleDesc)
+{
+	return internal_get_result_type(functionId,
+									NULL,
+									NULL,
+									resultTypeId,
+									resultTupleDesc);
+}
+
+/*
+ * 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;
+	Oid			base_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, &base_rettype);
+	switch (result)
+	{
+		case TYPEFUNC_COMPOSITE:
+		case TYPEFUNC_COMPOSITE_DOMAIN:
+			if (resultTupleDesc)
+				*resultTupleDesc = lookup_rowtype_tupdesc_copy(base_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;
+}
+
+/*
+ * get_expr_result_tupdesc
+ *		Get a tupdesc describing the result of a composite-valued expression
+ *
+ * If expression is not composite or rowtype can't be determined, returns NULL
+ * if noError is true, else throws error.
+ *
+ * This is a simpler version of get_expr_result_type() for use when the caller
+ * is only interested in determinate rowtype results.
+ */
+TupleDesc
+get_expr_result_tupdesc(Node *expr, bool noError)
+{
+	TupleDesc	tupleDesc;
+	TypeFuncClass functypclass;
+
+	functypclass = get_expr_result_type(expr, NULL, &tupleDesc);
+
+	if (functypclass == TYPEFUNC_COMPOSITE ||
+		functypclass == TYPEFUNC_COMPOSITE_DOMAIN)
+		return tupleDesc;
+
+	if (!noError)
+	{
+		Oid			exprTypeId = exprType(expr);
+
+		if (exprTypeId != RECORDOID)
+			ereport(ERROR,
+					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+					 errmsg("type %s is not composite",
+							format_type_be(exprTypeId))));
+		else
+			ereport(ERROR,
+					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
+					 errmsg("record type has not been registered")));
+	}
+
+	return NULL;
+}
+
+/*
+ * Resolve actual type of ANYELEMENT from other polymorphic inputs
+ *
+ * Note: the error cases here and in the sibling functions below are not
+ * really user-facing; they could only occur if the function signature is
+ * incorrect or the parser failed to enforce consistency of the actual
+ * argument types.  Hence, we don't sweat too much over the error messages.
+ */
+static void
+resolve_anyelement_from_others(polymorphic_actuals *actuals)
+{
+	if (OidIsValid(actuals->anyarray_type))
+	{
+		/* Use the element type corresponding to actual type */
+		Oid			array_base_type = getBaseType(actuals->anyarray_type);
+		Oid			array_typelem = get_element_type(array_base_type);
+
+		if (!OidIsValid(array_typelem))
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("argument declared %s is not an array but type %s",
+							"anyarray",
+							format_type_be(array_base_type))));
+		actuals->anyelement_type = array_typelem;
+	}
+	else if (OidIsValid(actuals->anyrange_type))
+	{
+		/* Use the element type corresponding to actual type */
+		Oid			range_base_type = getBaseType(actuals->anyrange_type);
+		Oid			range_typelem = get_range_subtype(range_base_type);
+
+		if (!OidIsValid(range_typelem))
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("argument declared %s is not a range type but type %s",
+							"anyrange",
+							format_type_be(range_base_type))));
+		actuals->anyelement_type = range_typelem;
+	}
+	else if (OidIsValid(actuals->anymultirange_type))
+	{
+		/* Use the element type based on the multirange type */
+		Oid			multirange_base_type;
+		Oid			multirange_typelem;
+		Oid			range_base_type;
+		Oid			range_typelem;
+
+		multirange_base_type = getBaseType(actuals->anymultirange_type);
+		multirange_typelem = get_multirange_range(multirange_base_type);
+		if (!OidIsValid(multirange_typelem))
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("argument declared %s is not a multirange type but type %s",
+							"anymultirange",
+							format_type_be(multirange_base_type))));
+
+		range_base_type = getBaseType(multirange_typelem);
+		range_typelem = get_range_subtype(range_base_type);
+
+		if (!OidIsValid(range_typelem))
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("argument declared %s does not contain a range type but type %s",
+							"anymultirange",
+							format_type_be(range_base_type))));
+		actuals->anyelement_type = range_typelem;
+	}
+	else
+		elog(ERROR, "could not determine polymorphic type");
+}
+
+/*
+ * Resolve actual type of ANYARRAY from other polymorphic inputs
+ */
+static void
+resolve_anyarray_from_others(polymorphic_actuals *actuals)
+{
+	/* If we don't know ANYELEMENT, resolve that first */
+	if (!OidIsValid(actuals->anyelement_type))
+		resolve_anyelement_from_others(actuals);
+
+	if (OidIsValid(actuals->anyelement_type))
+	{
+		/* Use the array type corresponding to actual type */
+		Oid			array_typeid = get_array_type(actuals->anyelement_type);
+
+		if (!OidIsValid(array_typeid))
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_OBJECT),
+					 errmsg("could not find array type for data type %s",
+							format_type_be(actuals->anyelement_type))));
+		actuals->anyarray_type = array_typeid;
+	}
+	else
+		elog(ERROR, "could not determine polymorphic type");
+}
+
+/*
+ * Resolve actual type of ANYRANGE from other polymorphic inputs
+ */
+static void
+resolve_anyrange_from_others(polymorphic_actuals *actuals)
+{
+	/*
+	 * We can't deduce a range type from other polymorphic array or base
+	 * types, because there may be multiple range types with the same subtype,
+	 * but we can deduce it from a polymorphic multirange type.
+	 */
+	if (OidIsValid(actuals->anymultirange_type))
+	{
+		/* Use the element type based on the multirange type */
+		Oid			multirange_base_type = getBaseType(actuals->anymultirange_type);
+		Oid			multirange_typelem = get_multirange_range(multirange_base_type);
+
+		if (!OidIsValid(multirange_typelem))
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("argument declared %s is not a multirange type but type %s",
+							"anymultirange",
+							format_type_be(multirange_base_type))));
+		actuals->anyrange_type = multirange_typelem;
+	}
+	else
+		elog(ERROR, "could not determine polymorphic type");
+}
+
+/*
+ * Resolve actual type of ANYMULTIRANGE from other polymorphic inputs
+ */
+static void
+resolve_anymultirange_from_others(polymorphic_actuals *actuals)
+{
+	/*
+	 * We can't deduce a multirange type from polymorphic array or base types,
+	 * because there may be multiple range types with the same subtype, but we
+	 * can deduce it from a polymorphic range type.
+	 */
+	if (OidIsValid(actuals->anyrange_type))
+	{
+		Oid			range_base_type = getBaseType(actuals->anyrange_type);
+		Oid			multirange_typeid = get_range_multirange(range_base_type);
+
+		if (!OidIsValid(multirange_typeid))
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_OBJECT),
+					 errmsg("could not find multirange type for data type %s",
+							format_type_be(actuals->anyrange_type))));
+		actuals->anymultirange_type = multirange_typeid;
+	}
+	else
+		elog(ERROR, "could not determine polymorphic type");
+}
+
+/*
+ * Given the result tuple descriptor for a function with OUT parameters,
+ * replace any polymorphic column types (ANYELEMENT etc) in the tupdesc
+ * with concrete data types deduced from the input arguments.
+ * declared_args is an oidvector of the function's declared input arg types
+ * (showing which are polymorphic), and call_expr is the call expression.
+ *
+ * Returns true if able to deduce all types, false if necessary information
+ * is not provided (call_expr is NULL or arg types aren't identifiable).
+ */
+static bool
+resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
+							Node *call_expr)
+{
+	int			natts = tupdesc->natts;
+	int			nargs = declared_args->dim1;
+	bool		have_polymorphic_result = false;
+	bool		have_anyelement_result = false;
+	bool		have_anyarray_result = false;
+	bool		have_anyrange_result = false;
+	bool		have_anymultirange_result = false;
+	bool		have_anycompatible_result = false;
+	bool		have_anycompatible_array_result = false;
+	bool		have_anycompatible_range_result = false;
+	bool		have_anycompatible_multirange_result = false;
+	polymorphic_actuals poly_actuals;
+	polymorphic_actuals anyc_actuals;
+	Oid			anycollation = InvalidOid;
+	Oid			anycompatcollation = InvalidOid;
+	int			i;
+
+	/* See if there are any polymorphic outputs; quick out if not */
+	for (i = 0; i < natts; i++)
+	{
+		switch (TupleDescAttr(tupdesc, i)->atttypid)
+		{
+			case ANYELEMENTOID:
+			case ANYNONARRAYOID:
+			case ANYENUMOID:
+				have_polymorphic_result = true;
+				have_anyelement_result = true;
+				break;
+			case ANYARRAYOID:
+				have_polymorphic_result = true;
+				have_anyarray_result = true;
+				break;
+			case ANYRANGEOID:
+				have_polymorphic_result = true;
+				have_anyrange_result = true;
+				break;
+			case ANYMULTIRANGEOID:
+				have_polymorphic_result = true;
+				have_anymultirange_result = true;
+				break;
+			case ANYCOMPATIBLEOID:
+			case ANYCOMPATIBLENONARRAYOID:
+				have_polymorphic_result = true;
+				have_anycompatible_result = true;
+				break;
+			case ANYCOMPATIBLEARRAYOID:
+				have_polymorphic_result = true;
+				have_anycompatible_array_result = true;
+				break;
+			case ANYCOMPATIBLERANGEOID:
+				have_polymorphic_result = true;
+				have_anycompatible_range_result = true;
+				break;
+			case ANYCOMPATIBLEMULTIRANGEOID:
+				have_polymorphic_result = true;
+				have_anycompatible_multirange_result = true;
+				break;
+			default:
+				break;
+		}
+	}
+	if (!have_polymorphic_result)
+		return true;
+
+	/*
+	 * Otherwise, extract actual datatype(s) from input arguments.  (We assume
+	 * the parser already validated consistency of the arguments.  Also, for
+	 * the ANYCOMPATIBLE pseudotype family, we expect that all matching
+	 * arguments were coerced to the selected common supertype, so that it
+	 * doesn't matter which one's exposed type we look at.)
+	 */
+	if (!call_expr)
+		return false;			/* no hope */
+
+	memset(&poly_actuals, 0, sizeof(poly_actuals));
+	memset(&anyc_actuals, 0, sizeof(anyc_actuals));
+
+	for (i = 0; i < nargs; i++)
+	{
+		switch (declared_args->values[i])
+		{
+			case ANYELEMENTOID:
+			case ANYNONARRAYOID:
+			case ANYENUMOID:
+				if (!OidIsValid(poly_actuals.anyelement_type))
+				{
+					poly_actuals.anyelement_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(poly_actuals.anyelement_type))
+						return false;
+				}
+				break;
+			case ANYARRAYOID:
+				if (!OidIsValid(poly_actuals.anyarray_type))
+				{
+					poly_actuals.anyarray_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(poly_actuals.anyarray_type))
+						return false;
+				}
+				break;
+			case ANYRANGEOID:
+				if (!OidIsValid(poly_actuals.anyrange_type))
+				{
+					poly_actuals.anyrange_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(poly_actuals.anyrange_type))
+						return false;
+				}
+				break;
+			case ANYMULTIRANGEOID:
+				if (!OidIsValid(poly_actuals.anymultirange_type))
+				{
+					poly_actuals.anymultirange_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(poly_actuals.anymultirange_type))
+						return false;
+				}
+				break;
+			case ANYCOMPATIBLEOID:
+			case ANYCOMPATIBLENONARRAYOID:
+				if (!OidIsValid(anyc_actuals.anyelement_type))
+				{
+					anyc_actuals.anyelement_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(anyc_actuals.anyelement_type))
+						return false;
+				}
+				break;
+			case ANYCOMPATIBLEARRAYOID:
+				if (!OidIsValid(anyc_actuals.anyarray_type))
+				{
+					anyc_actuals.anyarray_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(anyc_actuals.anyarray_type))
+						return false;
+				}
+				break;
+			case ANYCOMPATIBLERANGEOID:
+				if (!OidIsValid(anyc_actuals.anyrange_type))
+				{
+					anyc_actuals.anyrange_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(anyc_actuals.anyrange_type))
+						return false;
+				}
+				break;
+			case ANYCOMPATIBLEMULTIRANGEOID:
+				if (!OidIsValid(anyc_actuals.anymultirange_type))
+				{
+					anyc_actuals.anymultirange_type =
+						get_call_expr_argtype(call_expr, i);
+					if (!OidIsValid(anyc_actuals.anymultirange_type))
+						return false;
+				}
+				break;
+			default:
+				break;
+		}
+	}
+
+	/* If needed, deduce one polymorphic type from others */
+	if (have_anyelement_result && !OidIsValid(poly_actuals.anyelement_type))
+		resolve_anyelement_from_others(&poly_actuals);
+
+	if (have_anyarray_result && !OidIsValid(poly_actuals.anyarray_type))
+		resolve_anyarray_from_others(&poly_actuals);
+
+	if (have_anyrange_result && !OidIsValid(poly_actuals.anyrange_type))
+		resolve_anyrange_from_others(&poly_actuals);
+
+	if (have_anymultirange_result && !OidIsValid(poly_actuals.anymultirange_type))
+		resolve_anymultirange_from_others(&poly_actuals);
+
+	if (have_anycompatible_result && !OidIsValid(anyc_actuals.anyelement_type))
+		resolve_anyelement_from_others(&anyc_actuals);
+
+	if (have_anycompatible_array_result && !OidIsValid(anyc_actuals.anyarray_type))
+		resolve_anyarray_from_others(&anyc_actuals);
+
+	if (have_anycompatible_range_result && !OidIsValid(anyc_actuals.anyrange_type))
+		resolve_anyrange_from_others(&anyc_actuals);
+
+	if (have_anycompatible_multirange_result && !OidIsValid(anyc_actuals.anymultirange_type))
+		resolve_anymultirange_from_others(&anyc_actuals);
+
+	/*
+	 * Identify the collation to use for polymorphic OUT parameters. (It'll
+	 * necessarily be the same for both anyelement and anyarray, likewise for
+	 * anycompatible and anycompatiblearray.)  Note that range types are not
+	 * collatable, so any possible internal collation of a range type is not
+	 * considered here.
+	 */
+	if (OidIsValid(poly_actuals.anyelement_type))
+		anycollation = get_typcollation(poly_actuals.anyelement_type);
+	else if (OidIsValid(poly_actuals.anyarray_type))
+		anycollation = get_typcollation(poly_actuals.anyarray_type);
+
+	if (OidIsValid(anyc_actuals.anyelement_type))
+		anycompatcollation = get_typcollation(anyc_actuals.anyelement_type);
+	else if (OidIsValid(anyc_actuals.anyarray_type))
+		anycompatcollation = get_typcollation(anyc_actuals.anyarray_type);
+
+	if (OidIsValid(anycollation) || OidIsValid(anycompatcollation))
+	{
+		/*
+		 * The types are collatable, so consider whether to use a nondefault
+		 * collation.  We do so if we can identify the input collation used
+		 * for the function.
+		 */
+		Oid			inputcollation = exprInputCollation(call_expr);
+
+		if (OidIsValid(inputcollation))
+		{
+			if (OidIsValid(anycollation))
+				anycollation = inputcollation;
+			if (OidIsValid(anycompatcollation))
+				anycompatcollation = inputcollation;
+		}
+	}
+
+	/* And finally replace the tuple column types as needed */
+	for (i = 0; i < natts; i++)
+	{
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
+
+		switch (att->atttypid)
+		{
+			case ANYELEMENTOID:
+			case ANYNONARRAYOID:
+			case ANYENUMOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   poly_actuals.anyelement_type,
+								   -1,
+								   0);
+				TupleDescInitEntryCollation(tupdesc, i + 1, anycollation);
+				break;
+			case ANYARRAYOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   poly_actuals.anyarray_type,
+								   -1,
+								   0);
+				TupleDescInitEntryCollation(tupdesc, i + 1, anycollation);
+				break;
+			case ANYRANGEOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   poly_actuals.anyrange_type,
+								   -1,
+								   0);
+				/* no collation should be attached to a range type */
+				break;
+			case ANYMULTIRANGEOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   poly_actuals.anymultirange_type,
+								   -1,
+								   0);
+				/* no collation should be attached to a multirange type */
+				break;
+			case ANYCOMPATIBLEOID:
+			case ANYCOMPATIBLENONARRAYOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   anyc_actuals.anyelement_type,
+								   -1,
+								   0);
+				TupleDescInitEntryCollation(tupdesc, i + 1, anycompatcollation);
+				break;
+			case ANYCOMPATIBLEARRAYOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   anyc_actuals.anyarray_type,
+								   -1,
+								   0);
+				TupleDescInitEntryCollation(tupdesc, i + 1, anycompatcollation);
+				break;
+			case ANYCOMPATIBLERANGEOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   anyc_actuals.anyrange_type,
+								   -1,
+								   0);
+				/* no collation should be attached to a range type */
+				break;
+			case ANYCOMPATIBLEMULTIRANGEOID:
+				TupleDescInitEntry(tupdesc, i + 1,
+								   NameStr(att->attname),
+								   anyc_actuals.anymultirange_type,
+								   -1,
+								   0);
+				/* no collation should be attached to a multirange type */
+				break;
+			default:
+				break;
+		}
+	}
+
+	return true;
+}
+
+/*
+ * Given the declared argument types and modes for a function, replace any
+ * polymorphic types (ANYELEMENT etc) in argtypes[] with concrete data types
+ * deduced from the input arguments found in call_expr.
+ *
+ * Returns true if able to deduce all types, false if necessary information
+ * is not provided (call_expr is NULL or arg types aren't identifiable).
+ *
+ * This is the same logic as resolve_polymorphic_tupdesc, but with a different
+ * argument representation, and slightly different output responsibilities.
+ *
+ * argmodes may be NULL, in which case all arguments are assumed to be IN mode.
+ */
+bool
+resolve_polymorphic_argtypes(int numargs, Oid *argtypes, char *argmodes,
+							 Node *call_expr)
+{
+	bool		have_polymorphic_result = false;
+	bool		have_anyelement_result = false;
+	bool		have_anyarray_result = false;
+	bool		have_anyrange_result = false;
+	bool		have_anymultirange_result = false;
+	bool		have_anycompatible_result = false;
+	bool		have_anycompatible_array_result = false;
+	bool		have_anycompatible_range_result = false;
+	bool		have_anycompatible_multirange_result = false;
+	polymorphic_actuals poly_actuals;
+	polymorphic_actuals anyc_actuals;
+	int			inargno;
+	int			i;
+
+	/*
+	 * First pass: resolve polymorphic inputs, check for outputs.  As in
+	 * resolve_polymorphic_tupdesc, we rely on the parser to have enforced
+	 * type consistency and coerced ANYCOMPATIBLE args to a common supertype.
+	 */
+	memset(&poly_actuals, 0, sizeof(poly_actuals));
+	memset(&anyc_actuals, 0, sizeof(anyc_actuals));
+	inargno = 0;
+	for (i = 0; i < numargs; i++)
+	{
+		char		argmode = argmodes ? argmodes[i] : PROARGMODE_IN;
+
+		switch (argtypes[i])
+		{
+			case ANYELEMENTOID:
+			case ANYNONARRAYOID:
+			case ANYENUMOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anyelement_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(poly_actuals.anyelement_type))
+					{
+						poly_actuals.anyelement_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(poly_actuals.anyelement_type))
+							return false;
+					}
+					argtypes[i] = poly_actuals.anyelement_type;
+				}
+				break;
+			case ANYARRAYOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anyarray_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(poly_actuals.anyarray_type))
+					{
+						poly_actuals.anyarray_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(poly_actuals.anyarray_type))
+							return false;
+					}
+					argtypes[i] = poly_actuals.anyarray_type;
+				}
+				break;
+			case ANYRANGEOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anyrange_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(poly_actuals.anyrange_type))
+					{
+						poly_actuals.anyrange_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(poly_actuals.anyrange_type))
+							return false;
+					}
+					argtypes[i] = poly_actuals.anyrange_type;
+				}
+				break;
+			case ANYMULTIRANGEOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anymultirange_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(poly_actuals.anymultirange_type))
+					{
+						poly_actuals.anymultirange_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(poly_actuals.anymultirange_type))
+							return false;
+					}
+					argtypes[i] = poly_actuals.anymultirange_type;
+				}
+				break;
+			case ANYCOMPATIBLEOID:
+			case ANYCOMPATIBLENONARRAYOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anycompatible_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(anyc_actuals.anyelement_type))
+					{
+						anyc_actuals.anyelement_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(anyc_actuals.anyelement_type))
+							return false;
+					}
+					argtypes[i] = anyc_actuals.anyelement_type;
+				}
+				break;
+			case ANYCOMPATIBLEARRAYOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anycompatible_array_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(anyc_actuals.anyarray_type))
+					{
+						anyc_actuals.anyarray_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(anyc_actuals.anyarray_type))
+							return false;
+					}
+					argtypes[i] = anyc_actuals.anyarray_type;
+				}
+				break;
+			case ANYCOMPATIBLERANGEOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anycompatible_range_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(anyc_actuals.anyrange_type))
+					{
+						anyc_actuals.anyrange_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(anyc_actuals.anyrange_type))
+							return false;
+					}
+					argtypes[i] = anyc_actuals.anyrange_type;
+				}
+				break;
+			case ANYCOMPATIBLEMULTIRANGEOID:
+				if (argmode == PROARGMODE_OUT || argmode == PROARGMODE_TABLE)
+				{
+					have_polymorphic_result = true;
+					have_anycompatible_multirange_result = true;
+				}
+				else
+				{
+					if (!OidIsValid(anyc_actuals.anymultirange_type))
+					{
+						anyc_actuals.anymultirange_type =
+							get_call_expr_argtype(call_expr, inargno);
+						if (!OidIsValid(anyc_actuals.anymultirange_type))
+							return false;
+					}
+					argtypes[i] = anyc_actuals.anymultirange_type;
+				}
+				break;
+			default:
+				break;
+		}
+		if (argmode != PROARGMODE_OUT && argmode != PROARGMODE_TABLE)
+			inargno++;
+	}
+
+	/* Done? */
+	if (!have_polymorphic_result)
+		return true;
+
+	/* If needed, deduce one polymorphic type from others */
+	if (have_anyelement_result && !OidIsValid(poly_actuals.anyelement_type))
+		resolve_anyelement_from_others(&poly_actuals);
+
+	if (have_anyarray_result && !OidIsValid(poly_actuals.anyarray_type))
+		resolve_anyarray_from_others(&poly_actuals);
+
+	if (have_anyrange_result && !OidIsValid(poly_actuals.anyrange_type))
+		resolve_anyrange_from_others(&poly_actuals);
+
+	if (have_anymultirange_result && !OidIsValid(poly_actuals.anymultirange_type))
+		resolve_anymultirange_from_others(&poly_actuals);
+
+	if (have_anycompatible_result && !OidIsValid(anyc_actuals.anyelement_type))
+		resolve_anyelement_from_others(&anyc_actuals);
+
+	if (have_anycompatible_array_result && !OidIsValid(anyc_actuals.anyarray_type))
+		resolve_anyarray_from_others(&anyc_actuals);
+
+	if (have_anycompatible_range_result && !OidIsValid(anyc_actuals.anyrange_type))
+		resolve_anyrange_from_others(&anyc_actuals);
+
+	if (have_anycompatible_multirange_result && !OidIsValid(anyc_actuals.anymultirange_type))
+		resolve_anymultirange_from_others(&anyc_actuals);
+
+	/* And finally replace the output column types as needed */
+	for (i = 0; i < numargs; i++)
+	{
+		switch (argtypes[i])
+		{
+			case ANYELEMENTOID:
+			case ANYNONARRAYOID:
+			case ANYENUMOID:
+				argtypes[i] = poly_actuals.anyelement_type;
+				break;
+			case ANYARRAYOID:
+				argtypes[i] = poly_actuals.anyarray_type;
+				break;
+			case ANYRANGEOID:
+				argtypes[i] = poly_actuals.anyrange_type;
+				break;
+			case ANYMULTIRANGEOID:
+				argtypes[i] = poly_actuals.anymultirange_type;
+				break;
+			case ANYCOMPATIBLEOID:
+			case ANYCOMPATIBLENONARRAYOID:
+				argtypes[i] = anyc_actuals.anyelement_type;
+				break;
+			case ANYCOMPATIBLEARRAYOID:
+				argtypes[i] = anyc_actuals.anyarray_type;
+				break;
+			case ANYCOMPATIBLERANGEOID:
+				argtypes[i] = anyc_actuals.anyrange_type;
+				break;
+			case ANYCOMPATIBLEMULTIRANGEOID:
+				argtypes[i] = anyc_actuals.anymultirange_type;
+				break;
+			default:
+				break;
+		}
+	}
+
+	return true;
+}
+
+/*
+ * get_type_func_class
+ *		Given the type OID, obtain its TYPEFUNC classification.
+ *		Also, if it's a domain, return the base type OID.
+ *
+ * This is intended to centralize a bunch of formerly ad-hoc code for
+ * classifying types.  The categories used here are useful for deciding
+ * how to handle functions returning the datatype.
+ */
+static TypeFuncClass
+get_type_func_class(Oid typid, Oid *base_typeid)
+{
+	*base_typeid = typid;
+
+	switch (get_typtype(typid))
+	{
+		case TYPTYPE_COMPOSITE:
+			return TYPEFUNC_COMPOSITE;
+		case TYPTYPE_BASE:
+		case TYPTYPE_ENUM:
+		case TYPTYPE_RANGE:
+		case TYPTYPE_MULTIRANGE:
+			return TYPEFUNC_SCALAR;
+		case TYPTYPE_DOMAIN:
+			*base_typeid = typid = getBaseType(typid);
+			if (get_typtype(typid) == TYPTYPE_COMPOSITE)
+				return TYPEFUNC_COMPOSITE_DOMAIN;
+			else				/* domain base type can't be a pseudotype */
+				return TYPEFUNC_SCALAR;
+		case TYPTYPE_PSEUDO:
+			if (typid == RECORDOID)
+				return TYPEFUNC_RECORD;
+
+			/*
+			 * We treat VOID and CSTRING as legitimate scalar datatypes,
+			 * mostly for the convenience of the JDBC driver (which wants to
+			 * be able to do "SELECT * FROM foo()" for all legitimately
+			 * user-callable functions).
+			 */
+			if (typid == VOIDOID || typid == CSTRINGOID)
+				return TYPEFUNC_SCALAR;
+			return TYPEFUNC_OTHER;
+	}
+	/* shouldn't get here, probably */
+	return TYPEFUNC_OTHER;
+}
+
+
+/*
+ * get_func_arg_info
+ *
+ * Fetch info about the argument types, names, and IN/OUT modes from the
+ * pg_proc tuple.  Return value is the total number of arguments.
+ * Other results are palloc'd.  *p_argtypes is always filled in, but
+ * *p_argnames and *p_argmodes will be set NULL in the default cases
+ * (no names, and all IN arguments, respectively).
+ *
+ * Note that this function simply fetches what is in the pg_proc tuple;
+ * it doesn't do any interpretation of polymorphic types.
+ */
+int
+get_func_arg_info(HeapTuple procTup,
+				  Oid **p_argtypes, char ***p_argnames, char **p_argmodes)
+{
+	Form_pg_proc procStruct = (Form_pg_proc) GETSTRUCT(procTup);
+	Datum		proallargtypes;
+	Datum		proargmodes;
+	Datum		proargnames;
+	bool		isNull;
+	ArrayType  *arr;
+	int			numargs;
+	Datum	   *elems;
+	int			nelems;
+	int			i;
+
+	/* First discover the total number of parameters and get their types */
+	proallargtypes = SysCacheGetAttr(PROCOID, procTup,
+									 Anum_pg_proc_proallargtypes,
+									 &isNull);
+	if (!isNull)
+	{
+		/*
+		 * We expect the arrays to be 1-D arrays of the right types; verify
+		 * that.  For the OID and char arrays, we don't need to use
+		 * deconstruct_array() since the array data is just going to look like
+		 * a C array of values.
+		 */
+		arr = DatumGetArrayTypeP(proallargtypes);	/* ensure not toasted */
+		numargs = ARR_DIMS(arr)[0];
+		if (ARR_NDIM(arr) != 1 ||
+			numargs < 0 ||
+			ARR_HASNULL(arr) ||
+			ARR_ELEMTYPE(arr) != OIDOID)
+			elog(ERROR, "proallargtypes is not a 1-D Oid array or it contains nulls");
+		Assert(numargs >= procStruct->pronargs);
+		*p_argtypes = (Oid *) palloc(numargs * sizeof(Oid));
+		memcpy(*p_argtypes, ARR_DATA_PTR(arr),
+			   numargs * sizeof(Oid));
+	}
+	else
+	{
+		/* If no proallargtypes, use proargtypes */
+		numargs = procStruct->proargtypes.dim1;
+		Assert(numargs == procStruct->pronargs);
+		*p_argtypes = (Oid *) palloc(numargs * sizeof(Oid));
+		memcpy(*p_argtypes, procStruct->proargtypes.values,
+			   numargs * sizeof(Oid));
+	}
+
+	/* Get argument names, if available */
+	proargnames = SysCacheGetAttr(PROCOID, procTup,
+								  Anum_pg_proc_proargnames,
+								  &isNull);
+	if (isNull)
+		*p_argnames = NULL;
+	else
+	{
+		deconstruct_array(DatumGetArrayTypeP(proargnames),
+						  TEXTOID, -1, false, TYPALIGN_INT,
+						  &elems, NULL, &nelems);
+		if (nelems != numargs)	/* should not happen */
+			elog(ERROR, "proargnames must have the same number of elements as the function has arguments");
+		*p_argnames = (char **) palloc(sizeof(char *) * numargs);
+		for (i = 0; i < numargs; i++)
+			(*p_argnames)[i] = TextDatumGetCString(elems[i]);
+	}
+
+	/* Get argument modes, if available */
+	proargmodes = SysCacheGetAttr(PROCOID, procTup,
+								  Anum_pg_proc_proargmodes,
+								  &isNull);
+	if (isNull)
+		*p_argmodes = NULL;
+	else
+	{
+		arr = DatumGetArrayTypeP(proargmodes);	/* ensure not toasted */
+		if (ARR_NDIM(arr) != 1 ||
+			ARR_DIMS(arr)[0] != numargs ||
+			ARR_HASNULL(arr) ||
+			ARR_ELEMTYPE(arr) != CHAROID)
+			elog(ERROR, "proargmodes is not a 1-D char array of length %d or it contains nulls",
+				 numargs);
+		*p_argmodes = (char *) palloc(numargs * sizeof(char));
+		memcpy(*p_argmodes, ARR_DATA_PTR(arr),
+			   numargs * sizeof(char));
+	}
+
+	return numargs;
+}
+
+/*
+ * get_func_trftypes
+ *
+ * Returns the number of transformed types used by the function.
+ * If there are any, a palloc'd array of the type OIDs is returned
+ * into *p_trftypes.
+ */
+int
+get_func_trftypes(HeapTuple procTup,
+				  Oid **p_trftypes)
+{
+	Datum		protrftypes;
+	ArrayType  *arr;
+	int			nelems;
+	bool		isNull;
+
+	protrftypes = SysCacheGetAttr(PROCOID, procTup,
+								  Anum_pg_proc_protrftypes,
+								  &isNull);
+	if (!isNull)
+	{
+		/*
+		 * We expect the arrays to be 1-D arrays of the right types; verify
+		 * that.  For the OID and char arrays, we don't need to use
+		 * deconstruct_array() since the array data is just going to look like
+		 * a C array of values.
+		 */
+		arr = DatumGetArrayTypeP(protrftypes);	/* ensure not toasted */
+		nelems = ARR_DIMS(arr)[0];
+		if (ARR_NDIM(arr) != 1 ||
+			nelems < 0 ||
+			ARR_HASNULL(arr) ||
+			ARR_ELEMTYPE(arr) != OIDOID)
+			elog(ERROR, "protrftypes is not a 1-D Oid array or it contains nulls");
+		*p_trftypes = (Oid *) palloc(nelems * sizeof(Oid));
+		memcpy(*p_trftypes, ARR_DATA_PTR(arr),
+			   nelems * sizeof(Oid));
+
+		return nelems;
+	}
+	else
+		return 0;
+}
+
+/*
+ * get_func_input_arg_names
+ *
+ * Extract the names of input arguments only, given a function's
+ * proargnames and proargmodes entries in Datum form.
+ *
+ * Returns the number of input arguments, which is the length of the
+ * palloc'd array returned to *arg_names.  Entries for unnamed args
+ * are set to NULL.  You don't get anything if proargnames is NULL.
+ */
+int
+get_func_input_arg_names(Datum proargnames, Datum proargmodes,
+						 char ***arg_names)
+{
+	ArrayType  *arr;
+	int			numargs;
+	Datum	   *argnames;
+	char	   *argmodes;
+	char	  **inargnames;
+	int			numinargs;
+	int			i;
+
+	/* Do nothing if null proargnames */
+	if (proargnames == PointerGetDatum(NULL))
+	{
+		*arg_names = NULL;
+		return 0;
+	}
+
+	/*
+	 * We expect the arrays to be 1-D arrays of the right types; verify that.
+	 * For proargmodes, we don't need to use deconstruct_array() since the
+	 * array data is just going to look like a C array of values.
+	 */
+	arr = DatumGetArrayTypeP(proargnames);	/* ensure not toasted */
+	if (ARR_NDIM(arr) != 1 ||
+		ARR_HASNULL(arr) ||
+		ARR_ELEMTYPE(arr) != TEXTOID)
+		elog(ERROR, "proargnames is not a 1-D text array or it contains nulls");
+	deconstruct_array(arr, TEXTOID, -1, false, TYPALIGN_INT,
+					  &argnames, NULL, &numargs);
+	if (proargmodes != PointerGetDatum(NULL))
+	{
+		arr = DatumGetArrayTypeP(proargmodes);	/* ensure not toasted */
+		if (ARR_NDIM(arr) != 1 ||
+			ARR_DIMS(arr)[0] != numargs ||
+			ARR_HASNULL(arr) ||
+			ARR_ELEMTYPE(arr) != CHAROID)
+			elog(ERROR, "proargmodes is not a 1-D char array of length %d or it contains nulls",
+				 numargs);
+		argmodes = (char *) ARR_DATA_PTR(arr);
+	}
+	else
+		argmodes = NULL;
+
+	/* zero elements probably shouldn't happen, but handle it gracefully */
+	if (numargs <= 0)
+	{
+		*arg_names = NULL;
+		return 0;
+	}
+
+	/* extract input-argument names */
+	inargnames = (char **) palloc(numargs * sizeof(char *));
+	numinargs = 0;
+	for (i = 0; i < numargs; i++)
+	{
+		if (argmodes == NULL ||
+			argmodes[i] == PROARGMODE_IN ||
+			argmodes[i] == PROARGMODE_INOUT ||
+			argmodes[i] == PROARGMODE_VARIADIC)
+		{
+			char	   *pname = TextDatumGetCString(argnames[i]);
+
+			if (pname[0] != '\0')
+				inargnames[numinargs] = pname;
+			else
+				inargnames[numinargs] = NULL;
+			numinargs++;
+		}
+	}
+
+	*arg_names = inargnames;
+	return numinargs;
+}
+
+
+/*
+ * get_func_result_name
+ *
+ * If the function has exactly one output parameter, and that parameter
+ * is named, return the name (as a palloc'd string).  Else return NULL.
+ *
+ * This is used to determine the default output column name for functions
+ * returning scalar types.
+ */
+char *
+get_func_result_name(Oid functionId)
+{
+	char	   *result;
+	HeapTuple	procTuple;
+	Datum		proargmodes;
+	Datum		proargnames;
+	bool		isnull;
+	ArrayType  *arr;
+	int			numargs;
+	char	   *argmodes;
+	Datum	   *argnames;
+	int			numoutargs;
+	int			nargnames;
+	int			i;
+
+	/* First fetch the function's pg_proc row */
+	procTuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(functionId));
+	if (!HeapTupleIsValid(procTuple))
+		elog(ERROR, "cache lookup failed for function %u", functionId);
+
+	/* If there are no named OUT parameters, return NULL */
+	if (heap_attisnull(procTuple, Anum_pg_proc_proargmodes, NULL) ||
+		heap_attisnull(procTuple, Anum_pg_proc_proargnames, NULL))
+		result = NULL;
+	else
+	{
+		/* Get the data out of the tuple */
+		proargmodes = SysCacheGetAttr(PROCOID, procTuple,
+									  Anum_pg_proc_proargmodes,
+									  &isnull);
+		Assert(!isnull);
+		proargnames = SysCacheGetAttr(PROCOID, procTuple,
+									  Anum_pg_proc_proargnames,
+									  &isnull);
+		Assert(!isnull);
+
+		/*
+		 * We expect the arrays to be 1-D arrays of the right types; verify
+		 * that.  For the char array, we don't need to use deconstruct_array()
+		 * since the array data is just going to look like a C array of
+		 * values.
+		 */
+		arr = DatumGetArrayTypeP(proargmodes);	/* ensure not toasted */
+		numargs = ARR_DIMS(arr)[0];
+		if (ARR_NDIM(arr) != 1 ||
+			numargs < 0 ||
+			ARR_HASNULL(arr) ||
+			ARR_ELEMTYPE(arr) != CHAROID)
+			elog(ERROR, "proargmodes is not a 1-D char array or it contains nulls");
+		argmodes = (char *) ARR_DATA_PTR(arr);
+		arr = DatumGetArrayTypeP(proargnames);	/* ensure not toasted */
+		if (ARR_NDIM(arr) != 1 ||
+			ARR_DIMS(arr)[0] != numargs ||
+			ARR_HASNULL(arr) ||
+			ARR_ELEMTYPE(arr) != TEXTOID)
+			elog(ERROR, "proargnames is not a 1-D text array of length %d or it contains nulls",
+				 numargs);
+		deconstruct_array(arr, TEXTOID, -1, false, TYPALIGN_INT,
+						  &argnames, NULL, &nargnames);
+		Assert(nargnames == numargs);
+
+		/* scan for output argument(s) */
+		result = NULL;
+		numoutargs = 0;
+		for (i = 0; i < numargs; i++)
+		{
+			if (argmodes[i] == PROARGMODE_IN ||
+				argmodes[i] == PROARGMODE_VARIADIC)
+				continue;
+			Assert(argmodes[i] == PROARGMODE_OUT ||
+				   argmodes[i] == PROARGMODE_INOUT ||
+				   argmodes[i] == PROARGMODE_TABLE);
+			if (++numoutargs > 1)
+			{
+				/* multiple out args, so forget it */
+				result = NULL;
+				break;
+			}
+			result = TextDatumGetCString(argnames[i]);
+			if (result == NULL || result[0] == '\0')
+			{
+				/* Parameter is not named, so forget it */
+				result = NULL;
+				break;
+			}
+		}
+	}
+
+	ReleaseSysCache(procTuple);
+
+	return result;
+}
+
+
+/*
+ * build_function_result_tupdesc_t
+ *
+ * Given a pg_proc row for a function, return a tuple descriptor for the
+ * result rowtype, or NULL if the function does not have OUT parameters.
+ *
+ * Note that this does not handle resolution of polymorphic types;
+ * that is deliberate.
+ */
+TupleDesc
+build_function_result_tupdesc_t(HeapTuple procTuple)
+{
+	Form_pg_proc procform = (Form_pg_proc) GETSTRUCT(procTuple);
+	Datum		proallargtypes;
+	Datum		proargmodes;
+	Datum		proargnames;
+	bool		isnull;
+
+	/* Return NULL if the function isn't declared to return RECORD */
+	if (procform->prorettype != RECORDOID)
+		return NULL;
+
+	/* If there are no OUT parameters, return NULL */
+	if (heap_attisnull(procTuple, Anum_pg_proc_proallargtypes, NULL) ||
+		heap_attisnull(procTuple, Anum_pg_proc_proargmodes, NULL))
+		return NULL;
+
+	/* Get the data out of the tuple */
+	proallargtypes = SysCacheGetAttr(PROCOID, procTuple,
+									 Anum_pg_proc_proallargtypes,
+									 &isnull);
+	Assert(!isnull);
+	proargmodes = SysCacheGetAttr(PROCOID, procTuple,
+								  Anum_pg_proc_proargmodes,
+								  &isnull);
+	Assert(!isnull);
+	proargnames = SysCacheGetAttr(PROCOID, procTuple,
+								  Anum_pg_proc_proargnames,
+								  &isnull);
+	if (isnull)
+		proargnames = PointerGetDatum(NULL);	/* just to be sure */
+
+	return build_function_result_tupdesc_d(procform->prokind,
+										   proallargtypes,
+										   proargmodes,
+										   proargnames);
+}
+
+/*
+ * build_function_result_tupdesc_d
+ *
+ * Build a RECORD function's tupledesc from the pg_proc proallargtypes,
+ * proargmodes, and proargnames arrays.  This is split out for the
+ * convenience of ProcedureCreate, which needs to be able to compute the
+ * tupledesc before actually creating the function.
+ *
+ * For functions (but not for procedures), returns NULL if there are not at
+ * least two OUT or INOUT arguments.
+ */
+TupleDesc
+build_function_result_tupdesc_d(char prokind,
+								Datum proallargtypes,
+								Datum proargmodes,
+								Datum proargnames)
+{
+	TupleDesc	desc;
+	ArrayType  *arr;
+	int			numargs;
+	Oid		   *argtypes;
+	char	   *argmodes;
+	Datum	   *argnames = NULL;
+	Oid		   *outargtypes;
+	char	  **outargnames;
+	int			numoutargs;
+	int			nargnames;
+	int			i;
+
+	/* Can't have output args if columns are null */
+	if (proallargtypes == PointerGetDatum(NULL) ||
+		proargmodes == PointerGetDatum(NULL))
+		return NULL;
+
+	/*
+	 * We expect the arrays to be 1-D arrays of the right types; verify that.
+	 * For the OID and char arrays, we don't need to use deconstruct_array()
+	 * since the array data is just going to look like a C array of values.
+	 */
+	arr = DatumGetArrayTypeP(proallargtypes);	/* ensure not toasted */
+	numargs = ARR_DIMS(arr)[0];
+	if (ARR_NDIM(arr) != 1 ||
+		numargs < 0 ||
+		ARR_HASNULL(arr) ||
+		ARR_ELEMTYPE(arr) != OIDOID)
+		elog(ERROR, "proallargtypes is not a 1-D Oid array or it contains nulls");
+	argtypes = (Oid *) ARR_DATA_PTR(arr);
+	arr = DatumGetArrayTypeP(proargmodes);	/* ensure not toasted */
+	if (ARR_NDIM(arr) != 1 ||
+		ARR_DIMS(arr)[0] != numargs ||
+		ARR_HASNULL(arr) ||
+		ARR_ELEMTYPE(arr) != CHAROID)
+		elog(ERROR, "proargmodes is not a 1-D char array of length %d or it contains nulls",
+			 numargs);
+	argmodes = (char *) ARR_DATA_PTR(arr);
+	if (proargnames != PointerGetDatum(NULL))
+	{
+		arr = DatumGetArrayTypeP(proargnames);	/* ensure not toasted */
+		if (ARR_NDIM(arr) != 1 ||
+			ARR_DIMS(arr)[0] != numargs ||
+			ARR_HASNULL(arr) ||
+			ARR_ELEMTYPE(arr) != TEXTOID)
+			elog(ERROR, "proargnames is not a 1-D text array of length %d or it contains nulls",
+				 numargs);
+		deconstruct_array(arr, TEXTOID, -1, false, TYPALIGN_INT,
+						  &argnames, NULL, &nargnames);
+		Assert(nargnames == numargs);
+	}
+
+	/* zero elements probably shouldn't happen, but handle it gracefully */
+	if (numargs <= 0)
+		return NULL;
+
+	/* extract output-argument types and names */
+	outargtypes = (Oid *) palloc(numargs * sizeof(Oid));
+	outargnames = (char **) palloc(numargs * sizeof(char *));
+	numoutargs = 0;
+	for (i = 0; i < numargs; i++)
+	{
+		char	   *pname;
+
+		if (argmodes[i] == PROARGMODE_IN ||
+			argmodes[i] == PROARGMODE_VARIADIC)
+			continue;
+		Assert(argmodes[i] == PROARGMODE_OUT ||
+			   argmodes[i] == PROARGMODE_INOUT ||
+			   argmodes[i] == PROARGMODE_TABLE);
+		outargtypes[numoutargs] = argtypes[i];
+		if (argnames)
+			pname = TextDatumGetCString(argnames[i]);
+		else
+			pname = NULL;
+		if (pname == NULL || pname[0] == '\0')
+		{
+			/* Parameter is not named, so gin up a column name */
+			pname = psprintf("column%d", numoutargs + 1);
+		}
+		outargnames[numoutargs] = pname;
+		numoutargs++;
+	}
+
+	/*
+	 * If there is no output argument, or only one, the function does not
+	 * return tuples.
+	 */
+	if (numoutargs < 2 && prokind != PROKIND_PROCEDURE)
+		return NULL;
+
+	desc = CreateTemplateTupleDesc(numoutargs);
+	for (i = 0; i < numoutargs; i++)
+	{
+		TupleDescInitEntry(desc, i + 1,
+						   outargnames[i],
+						   outargtypes[i],
+						   -1,
+						   0);
+	}
+
+	return desc;
+}
+
+
+/*
+ * RelationNameGetTupleDesc
+ *
+ * Given a (possibly qualified) relation name, build a TupleDesc.
+ *
+ * Note: while this works as advertised, it's seldom the best way to
+ * build a tupdesc for a function's result type.  It's kept around
+ * only for backwards compatibility with existing user-written code.
+ */
+TupleDesc
+RelationNameGetTupleDesc(const char *relname)
+{
+	RangeVar   *relvar;
+	Relation	rel;
+	TupleDesc	tupdesc;
+	List	   *relname_list;
+
+	/* Open relation and copy the tuple description */
+	relname_list = stringToQualifiedNameList(relname);
+	relvar = makeRangeVarFromNameList(relname_list);
+	rel = relation_openrv(relvar, AccessShareLock);
+	tupdesc = CreateTupleDescCopy(RelationGetDescr(rel));
+	relation_close(rel, AccessShareLock);
+
+	return tupdesc;
+}
+
+/*
+ * TypeGetTupleDesc
+ *
+ * Given a type Oid, build a TupleDesc.  (In most cases you should be
+ * using get_call_result_type or one of its siblings instead of this
+ * routine, so that you can handle OUT parameters, RECORD result type,
+ * and polymorphic results.)
+ *
+ * If the type is composite, *and* a colaliases List is provided, *and*
+ * the List is of natts length, use the aliases instead of the relation
+ * attnames.  (NB: this usage is deprecated since it may result in
+ * creation of unnecessary transient record types.)
+ *
+ * If the type is a base type, a single item alias List is required.
+ */
+TupleDesc
+TypeGetTupleDesc(Oid typeoid, List *colaliases)
+{
+	Oid			base_typeoid;
+	TypeFuncClass functypclass = get_type_func_class(typeoid, &base_typeoid);
+	TupleDesc	tupdesc = NULL;
+
+	/*
+	 * Build a suitable tupledesc representing the output rows.  We
+	 * intentionally do not support TYPEFUNC_COMPOSITE_DOMAIN here, as it's
+	 * unlikely that legacy callers of this obsolete function would be
+	 * prepared to apply domain constraints.
+	 */
+	if (functypclass == TYPEFUNC_COMPOSITE)
+	{
+		/* Composite data type, e.g. a table's row type */
+		tupdesc = lookup_rowtype_tupdesc_copy(base_typeoid, -1);
+
+		if (colaliases != NIL)
+		{
+			int			natts = tupdesc->natts;
+			int			varattno;
+
+			/* does the list length match the number of attributes? */
+			if (list_length(colaliases) != natts)
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("number of aliases does not match number of columns")));
+
+			/* OK, use the aliases instead */
+			for (varattno = 0; varattno < natts; varattno++)
+			{
+				char	   *label = strVal(list_nth(colaliases, varattno));
+				Form_pg_attribute attr = TupleDescAttr(tupdesc, varattno);
+
+				if (label != NULL)
+					namestrcpy(&(attr->attname), label);
+			}
+
+			/* The tuple type is now an anonymous record type */
+			tupdesc->tdtypeid = RECORDOID;
+			tupdesc->tdtypmod = -1;
+		}
+	}
+	else if (functypclass == TYPEFUNC_SCALAR)
+	{
+		/* Base data type, i.e. scalar */
+		char	   *attname;
+
+		/* the alias list is required for base types */
+		if (colaliases == NIL)
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("no column alias was provided")));
+
+		/* the alias list length must be 1 */
+		if (list_length(colaliases) != 1)
+			ereport(ERROR,
+					(errcode(ERRCODE_DATATYPE_MISMATCH),
+					 errmsg("number of aliases does not match number of columns")));
+
+		/* OK, get the column alias */
+		attname = strVal(linitial(colaliases));
+
+		tupdesc = CreateTemplateTupleDesc(1);
+		TupleDescInitEntry(tupdesc,
+						   (AttrNumber) 1,
+						   attname,
+						   typeoid,
+						   -1,
+						   0);
+	}
+	else if (functypclass == TYPEFUNC_RECORD)
+	{
+		/* XXX can't support this because typmod wasn't passed in ... */
+		ereport(ERROR,
+				(errcode(ERRCODE_DATATYPE_MISMATCH),
+				 errmsg("could not determine row description for function returning record")));
+	}
+	else
+	{
+		/* crummy error message, but parser should have caught this */
+		elog(ERROR, "function in FROM has unsupported return type");
+	}
+
+	return tupdesc;
+}
+
+/*
+ * extract_variadic_args
+ *
+ * Extract a set of argument values, types and NULL markers for a given
+ * input function which makes use of a VARIADIC input whose argument list
+ * depends on the caller context. When doing a VARIADIC call, the caller
+ * has provided one argument made of an array of values, so deconstruct the
+ * array data before using it for the next processing. If no VARIADIC call
+ * is used, just fill in the status data based on all the arguments given
+ * by the caller.
+ *
+ * This function returns the number of arguments generated, or -1 in the
+ * case of "VARIADIC NULL".
+ */
+int
+extract_variadic_args(FunctionCallInfo fcinfo, int variadic_start,
+					  bool convert_unknown, Datum **args, Oid **types,
+					  bool **nulls)
+{
+	bool		variadic = get_fn_expr_variadic(fcinfo->flinfo);
+	Datum	   *args_res;
+	bool	   *nulls_res;
+	Oid		   *types_res;
+	int			nargs,
+				i;
+
+	*args = NULL;
+	*types = NULL;
+	*nulls = NULL;
+
+	if (variadic)
+	{
+		ArrayType  *array_in;
+		Oid			element_type;
+		bool		typbyval;
+		char		typalign;
+		int16		typlen;
+
+		Assert(PG_NARGS() == variadic_start + 1);
+
+		if (PG_ARGISNULL(variadic_start))
+			return -1;
+
+		array_in = PG_GETARG_ARRAYTYPE_P(variadic_start);
+		element_type = ARR_ELEMTYPE(array_in);
+
+		get_typlenbyvalalign(element_type,
+							 &typlen, &typbyval, &typalign);
+		deconstruct_array(array_in, element_type, typlen, typbyval,
+						  typalign, &args_res, &nulls_res,
+						  &nargs);
+
+		/* All the elements of the array have the same type */
+		types_res = (Oid *) palloc0(nargs * sizeof(Oid));
+		for (i = 0; i < nargs; i++)
+			types_res[i] = element_type;
+	}
+	else
+	{
+		nargs = PG_NARGS() - variadic_start;
+		Assert(nargs > 0);
+		nulls_res = (bool *) palloc0(nargs * sizeof(bool));
+		args_res = (Datum *) palloc0(nargs * sizeof(Datum));
+		types_res = (Oid *) palloc0(nargs * sizeof(Oid));
+
+		for (i = 0; i < nargs; i++)
+		{
+			nulls_res[i] = PG_ARGISNULL(i + variadic_start);
+			types_res[i] = get_fn_expr_argtype(fcinfo->flinfo,
+											   i + variadic_start);
+
+			/*
+			 * Turn a constant (more or less literal) value that's of unknown
+			 * type into text if required. Unknowns come in as a cstring
+			 * pointer. Note: for functions declared as taking type "any", the
+			 * parser will not do any type conversion on unknown-type literals
+			 * (that is, undecorated strings or NULLs).
+			 */
+			if (convert_unknown &&
+				types_res[i] == UNKNOWNOID &&
+				get_fn_expr_arg_stable(fcinfo->flinfo, i + variadic_start))
+			{
+				types_res[i] = TEXTOID;
+
+				if (PG_ARGISNULL(i + variadic_start))
+					args_res[i] = (Datum) 0;
+				else
+					args_res[i] =
+						CStringGetTextDatum(PG_GETARG_POINTER(i + variadic_start));
+			}
+			else
+			{
+				/* no conversion needed, just take the datum as given */
+				args_res[i] = PG_GETARG_DATUM(i + variadic_start);
+			}
+
+			if (!OidIsValid(types_res[i]) ||
+				(convert_unknown && types_res[i] == UNKNOWNOID))
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("could not determine data type for argument %d",
+								i + 1)));
+		}
+	}
+
+	/* Fill in results */
+	*args = args_res;
+	*nulls = nulls_res;
+	*types = types_res;
+
+	return nargs;
+}