Simplify and encapsulate tuple routing support code.

Instead of having ExecSetupPartitionTupleRouting return multiple out
parameters, have it return a pointer to a structure containing all of
those different things.  Also, provide and use a cleanup function,
ExecCleanupTupleRouting, instead of cleaning up all of the resources
allocated by ExecSetupPartitionTupleRouting individually.

Amit Khandekar, reviewed by Amit Langote, David Rowley, and me

Discussion: http://postgr.es/m/CAJ3gD9fWfxgKC+PfJZF3hkgAcNOy-LpfPxVYitDEXKHjeieWQQ@mail.gmail.com

2 files changed, 39 insertions, 17 deletions

diff --git a/src/include/executor/execPartition.h b/src/include/executor/execPartition.h
index f0998cb82fb..b5df357acdf 100644
--- a/src/include/executor/execPartition.h
+++ b/src/include/executor/execPartition.h
@@ -49,18 +49,47 @@ typedef struct PartitionDispatchData
 
 typedef struct PartitionDispatchData *PartitionDispatch;
 
-extern void ExecSetupPartitionTupleRouting(ModifyTableState *mtstate,
-							   Relation rel,
-							   Index resultRTindex,
-							   EState *estate,
-							   PartitionDispatch **pd,
-							   ResultRelInfo ***partitions,
-							   TupleConversionMap ***tup_conv_maps,
-							   TupleTableSlot **partition_tuple_slot,
-							   int *num_parted, int *num_partitions);
+/*-----------------------
+ * PartitionTupleRouting - Encapsulates all information required to execute
+ * tuple-routing between partitions.
+ *
+ * partition_dispatch_info		Array of PartitionDispatch objects with one
+ *								entry for every partitioned table in the
+ *								partition tree.
+ * num_dispatch					number of partitioned tables in the partition
+ *								tree (= length of partition_dispatch_info[])
+ * partitions					Array of ResultRelInfo* objects with one entry
+ *								for every leaf partition in the partition tree.
+ * num_partitions				Number of leaf partitions in the partition tree
+ *								(= 'partitions' array length)
+ * partition_tupconv_maps		Array of TupleConversionMap objects with one
+ *								entry for every leaf partition (required to
+ *								convert input tuple based on the root table's
+ *								rowtype to a leaf partition's rowtype after
+ *								tuple routing is done)
+ * partition_tuple_slot			TupleTableSlot to be used to manipulate any
+ *								given leaf partition's rowtype after that
+ *								partition is chosen for insertion by
+ *								tuple-routing.
+ *-----------------------
+ */
+typedef struct PartitionTupleRouting
+{
+	PartitionDispatch *partition_dispatch_info;
+	int			num_dispatch;
+	ResultRelInfo **partitions;
+	int			num_partitions;
+	TupleConversionMap **partition_tupconv_maps;
+	TupleTableSlot *partition_tuple_slot;
+} PartitionTupleRouting;
+
+extern PartitionTupleRouting *ExecSetupPartitionTupleRouting(ModifyTableState *mtstate,
+							   Relation rel, Index resultRTindex,
+							   EState *estate);
 extern int ExecFindPartition(ResultRelInfo *resultRelInfo,
 				  PartitionDispatch *pd,
 				  TupleTableSlot *slot,
 				  EState *estate);
+extern void ExecCleanupTupleRouting(PartitionTupleRouting *proute);
 
 #endif							/* EXECPARTITION_H */
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 3ad58cdfe7c..2a4f7407a16 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -985,15 +985,8 @@ typedef struct ModifyTableState
 	TupleTableSlot *mt_existing;	/* slot to store existing target tuple in */
 	List	   *mt_excludedtlist;	/* the excluded pseudo relation's tlist  */
 	TupleTableSlot *mt_conflproj;	/* CONFLICT ... SET ... projection target */
-	struct PartitionDispatchData **mt_partition_dispatch_info;
+	struct PartitionTupleRouting *mt_partition_tuple_routing;
 	/* Tuple-routing support info */
-	int			mt_num_dispatch;	/* Number of entries in the above array */
-	int			mt_num_partitions;	/* Number of members in the following
-									 * arrays */
-	ResultRelInfo **mt_partitions;	/* Per partition result relation pointers */
-	TupleConversionMap **mt_partition_tupconv_maps;
-	/* Per partition tuple conversion map */
-	TupleTableSlot *mt_partition_tuple_slot;
 	struct TransitionCaptureState *mt_transition_capture;
 	/* controls transition table population for specified operation */
 	struct TransitionCaptureState *mt_oc_transition_capture;