use QueryCompletion struct

Postgres introduced QueryCompletion struct. Hence a compat utility is
added to finish query completion for older versions and pg >= 13.

The commit on Postgres side:
2f9661311b83dc481fc19f6e3bda015392010a40

src/backend/distributed/commands/multi_copy.c

@@ -93,6 +93,7 @@
 #include "distributed/hash_helpers.h"
 #include "executor/executor.h"
 #include "foreign/foreign.h"
+#include "tcop/cmdtag.h"
 #include "libpq/libpq.h"
 #include "libpq/pqformat.h"
 #include "nodes/makefuncs.h"
@@ -211,8 +212,8 @@ typedef struct ShardConnections
 
 
 /* Local functions forward declarations */
-static void CopyToExistingShards(CopyStmt *copyStatement, char *completionTag);
+static void CopyToExistingShards(CopyStmt *copyStatement, QueryCompletionCompat *completionTag);
-static void CopyToNewShards(CopyStmt *copyStatement, char *completionTag, Oid relationId);
+static void CopyToNewShards(CopyStmt *copyStatement, QueryCompletionCompat *completionTag, Oid relationId);
 static void OpenCopyConnectionsForNewShards(CopyStmt *copyStatement,
 											ShardConnections *shardConnections, bool
 											stopOnFailure,
@@ -244,7 +245,7 @@ static FmgrInfo * TypeOutputFunctions(uint32 columnCount, Oid *typeIdArray,
 									  bool binaryFormat);
 static List * CopyGetAttnums(TupleDesc tupDesc, Relation rel, List *attnamelist);
 static bool CopyStatementHasFormat(CopyStmt *copyStatement, char *formatName);
-static void CitusCopyFrom(CopyStmt *copyStatement, char *completionTag);
+static void CitusCopyFrom(CopyStmt *copyStatement, QueryCompletionCompat *completionTag);
 static HTAB * CreateConnectionStateHash(MemoryContext memoryContext);
 static HTAB * CreateShardStateHash(MemoryContext memoryContext);
 static CopyConnectionState * GetConnectionState(HTAB *connectionStateHash,
@@ -277,7 +278,7 @@ static void UnclaimCopyConnections(List *connectionStateList);
 static void ShutdownCopyConnectionState(CopyConnectionState *connectionState,
 										CitusCopyDestReceiver *copyDest);
 static SelectStmt * CitusCopySelect(CopyStmt *copyStatement);
-static void CitusCopyTo(CopyStmt *copyStatement, char *completionTag);
+static void CitusCopyTo(CopyStmt *copyStatement, QueryCompletionCompat *completionTag);
 static int64 ForwardCopyDataFromConnection(CopyOutState copyOutState,
 										   MultiConnection *connection);
 
@@ -313,6 +314,7 @@ static bool CitusCopyDestReceiverReceive(TupleTableSlot *slot,
 static void CitusCopyDestReceiverShutdown(DestReceiver *destReceiver);
 static void CitusCopyDestReceiverDestroy(DestReceiver *destReceiver);
 static bool ContainsLocalPlacement(int64 shardId);
+static void CompleteCopyQueryTagCompat(QueryCompletionCompat* completionTag, uint64 processedRowCount);
 static void FinishLocalCopy(CitusCopyDestReceiver *copyDest);
 static void CloneCopyOutStateForLocalCopy(CopyOutState from, CopyOutState to);
 static bool ShouldExecuteCopyLocally(bool isIntermediateResult);
@@ -329,7 +331,7 @@ PG_FUNCTION_INFO_V1(citus_text_send_as_jsonb);
  * and the partition method of the distributed table.
  */
 static void
-CitusCopyFrom(CopyStmt *copyStatement, char *completionTag)
+CitusCopyFrom(CopyStmt *copyStatement, QueryCompletionCompat *completionTag)
 {
 	UseCoordinatedTransaction();
 
@@ -385,7 +387,7 @@ CitusCopyFrom(CopyStmt *copyStatement, char *completionTag)
  * rows.
  */
 static void
-CopyToExistingShards(CopyStmt *copyStatement, char *completionTag)
+CopyToExistingShards(CopyStmt *copyStatement, QueryCompletionCompat *completionTag)
 {
 	Oid tableId = RangeVarGetRelid(copyStatement->relation, NoLock, false);
 
@@ -554,8 +556,7 @@ CopyToExistingShards(CopyStmt *copyStatement, char *completionTag)
 
 	if (completionTag != NULL)
 	{
-		SafeSnprintf(completionTag, COMPLETION_TAG_BUFSIZE,
+		CompleteCopyQueryTagCompat(completionTag, processedRowCount);
-					 "COPY " UINT64_FORMAT, processedRowCount);
 	}
 }
 
@@ -565,7 +566,7 @@ CopyToExistingShards(CopyStmt *copyStatement, char *completionTag)
  * tables where we create new shards into which to copy rows.
  */
 static void
-CopyToNewShards(CopyStmt *copyStatement, char *completionTag, Oid relationId)
+CopyToNewShards(CopyStmt *copyStatement, QueryCompletionCompat *completionTag, Oid relationId)
 {
 	/* allocate column values and nulls arrays */
 	Relation distributedRelation = table_open(relationId, RowExclusiveLock);
@@ -739,9 +740,17 @@ CopyToNewShards(CopyStmt *copyStatement, char *completionTag, Oid relationId)
 
 	if (completionTag != NULL)
 	{
+		CompleteCopyQueryTagCompat(completionTag, processedRowCount);
+	}
+}
+
+static void CompleteCopyQueryTagCompat(QueryCompletionCompat* completionTag, uint64 processedRowCount) {
+	#if PG_VERSION_NUM >= PG_VERSION_13
+		SetQueryCompletion(completionTag, CMDTAG_COPY, processedRowCount);
+	#else
 		SafeSnprintf(completionTag, COMPLETION_TAG_BUFSIZE,
 				"COPY " UINT64_FORMAT, processedRowCount);
-	}
+	#endif
 }
 
 
@@ -2769,7 +2778,7 @@ CopyStatementHasFormat(CopyStmt *copyStatement, char *formatName)
  * further processing is needed.
  */
 Node *
-ProcessCopyStmt(CopyStmt *copyStatement, char *completionTag, const char *queryString)
+ProcessCopyStmt(CopyStmt *copyStatement, QueryCompletionCompat *completionTag, const char *queryString)
 {
 	/*
 	 * Handle special COPY "resultid" FROM STDIN WITH (format result) commands
@@ -2917,7 +2926,7 @@ CitusCopySelect(CopyStmt *copyStatement)
  * table dump.
  */
 static void
-CitusCopyTo(CopyStmt *copyStatement, char *completionTag)
+CitusCopyTo(CopyStmt *copyStatement, QueryCompletionCompat *completionTag)
 {
 	ListCell *shardIntervalCell = NULL;
 	int64 tuplesSent = 0;
@@ -3008,8 +3017,7 @@ CitusCopyTo(CopyStmt *copyStatement, char *completionTag)
 
 	if (completionTag != NULL)
 	{
-		SafeSnprintf(completionTag, COMPLETION_TAG_BUFSIZE, "COPY " UINT64_FORMAT,
+		CompleteCopyQueryTagCompat(completionTag, tuplesSent);
-					 tuplesSent);
 	}
 }
 

src/backend/distributed/commands/utility_hook.c

@@ -25,6 +25,8 @@
  *-------------------------------------------------------------------------
  */
 
+#include "distributed/pg_version_constants.h"
+
 #include "postgres.h"
 #include "miscadmin.h"
 
@@ -88,7 +90,9 @@ static bool IsDropSchemaOrDB(Node *parsetree);
  */
 void
 CitusProcessUtility(Node *node, const char *queryString, ProcessUtilityContext context,
-					ParamListInfo params, DestReceiver *dest, char *completionTag)
+					ParamListInfo params, DestReceiver *dest,
+					QueryCompletionCompat *completionTag
+					)
 {
 	PlannedStmt *plannedStmt = makeNode(PlannedStmt);
 	plannedStmt->commandType = CMD_UTILITY;
@@ -115,7 +119,8 @@ multi_ProcessUtility(PlannedStmt *pstmt,
 					 ParamListInfo params,
 					 struct QueryEnvironment *queryEnv,
 					 DestReceiver *dest,
-					 char *completionTag)
+					 QueryCompletionCompat *completionTag
+					 )
 {
 	Node *parsetree = pstmt->utilityStmt;
 	List *ddlJobs = NIL;

src/include/distributed/commands/multi_copy.h

@@ -15,6 +15,7 @@
 
 #include "distributed/metadata_utility.h"
 #include "distributed/metadata_cache.h"
+#include "distributed/version_compat.h"
 #include "nodes/execnodes.h"
 #include "nodes/parsenodes.h"
 #include "parser/parse_coerce.h"
@@ -155,7 +156,7 @@ extern void AppendCopyBinaryHeaders(CopyOutState headerOutputState);
 extern void AppendCopyBinaryFooters(CopyOutState footerOutputState);
 extern void EndRemoteCopy(int64 shardId, List *connectionList);
 extern List * CreateRangeTable(Relation rel, AclMode requiredAccess);
-extern Node * ProcessCopyStmt(CopyStmt *copyStatement, char *completionTag,
+extern Node * ProcessCopyStmt(CopyStmt *copyStatement, QueryCompletionCompat *completionTag,
 							  const char *queryString);
 extern void CheckCopyPermissions(CopyStmt *copyStatement);
 extern bool IsCopyResultStmt(CopyStmt *copyStatement);

src/include/distributed/commands/utility_hook.h

@@ -10,6 +10,8 @@
 #ifndef MULTI_UTILITY_H
 #define MULTI_UTILITY_H
 
+#include "distributed/pg_version_constants.h"
+
 #include "postgres.h"
 
 #include "utils/relcache.h"
@@ -51,10 +53,13 @@ typedef struct DDLJob
 extern void multi_ProcessUtility(PlannedStmt *pstmt, const char *queryString,
 								 ProcessUtilityContext context, ParamListInfo params,
 								 struct QueryEnvironment *queryEnv, DestReceiver *dest,
-								 char *completionTag);
+								 QueryCompletionCompat *completionTag
+								);
 extern void CitusProcessUtility(Node *node, const char *queryString,
 								ProcessUtilityContext context, ParamListInfo params,
-								DestReceiver *dest, char *completionTag);
+								DestReceiver *dest,
+								QueryCompletionCompat * completionTag
+								);
 extern void MarkInvalidateForeignKeyGraph(void);
 extern void InvalidateForeignKeyGraphForDDL(void);
 extern List * DDLTaskList(Oid relationId, const char *commandString);

src/include/distributed/version_compat.h

@@ -41,6 +41,7 @@
 #define varnoold varnosyn
 #define Set_ptr_value(a,b) a->ptr_value = b
 #define RangeTableEntryFromNSItem(a) a->p_rte
+#define QueryCompletionCompat QueryCompletion
 #else /* pre PG13 */
 #define lnext_compat(l, r) lnext(r)
 #define list_delete_cell_compat(l,c,p) list_delete_cell(l,c,p) 
@@ -52,6 +53,7 @@
 #define ExplainOnePlanCompat(a,b,c,d,e,f,g,h) ExplainOnePlan(a,b,c,d,e,f,g)
 #define Set_ptr_value(a,b) a->data.ptr_value = b
 #define RangeTableEntryFromNSItem(a) a
+#define QueryCompletionCompat char 
 #endif
 #if PG_VERSION_NUM >= PG_VERSION_12