libpqpline-separte-pipelineidle-state.diff

diff --git a/src/interfaces/libpq/fe-exec.c b/src/interfaces/libpq/fe-exec.c
index 919cf5741d..a8999911d7 100644
--- a/src/interfaces/libpq/fe-exec.c
+++ b/src/interfaces/libpq/fe-exec.c
@@ -1380,7 +1380,7 @@ pqAppendCmdQueueEntry(PGconn *conn, PGcmdQueueEntry *entry)
 			 * itself consume commands from the queue; if we're in any other
 			 * state, we don't have to do anything.
 			 */
-			if (conn->asyncStatus == PGASYNC_IDLE)
+			if (conn->asyncStatus == PGASYNC_PIPELINE_IDLE)
 				pqPipelineProcessQueue(conn);
 			break;
 	}
@@ -1778,6 +1778,10 @@ PQsendQueryStart(PGconn *conn, bool newQuery)
 				appendPQExpBufferStr(&conn->errorMessage,
 									 libpq_gettext("cannot queue commands during COPY\n"));
 				return false;
+			case PGASYNC_PIPELINE_IDLE:
+				appendPQExpBufferStr(&conn->errorMessage,
+									 libpq_gettext("unexpected PGASYNC_PIPELINE_IDLE state during COPY\n"));
+				return false;
 		}
 	}
 	else
@@ -2144,15 +2148,17 @@ PQgetResult(PGconn *conn)
 	{
 		case PGASYNC_IDLE:
 			res = NULL;			/* query is complete */
-			if (conn->pipelineStatus != PQ_PIPELINE_OFF)
-			{
-				/*
-				 * We're about to return the NULL that terminates the round of
-				 * results from the current query; prepare to send the results
-				 * of the next query when we're called next.
-				 */
-				pqPipelineProcessQueue(conn);
-			}
+			break;
+		case PGASYNC_PIPELINE_IDLE:
+			Assert (conn->pipelineStatus != PQ_PIPELINE_OFF);
+
+			res = NULL;			/* query is complete */
+			/*
+			 * We're about to return the NULL that terminates the round of
+			 * results from the current query; prepare to send the results
+			 * of the next query when we're called next.
+			 */
+			pqPipelineProcessQueue(conn);
 			break;
 		case PGASYNC_READY:
 
@@ -2174,7 +2180,7 @@ PQgetResult(PGconn *conn)
 				 * We're about to send the results of the current query.  Set
 				 * us idle now, and ...
 				 */
-				conn->asyncStatus = PGASYNC_IDLE;
+				conn->asyncStatus = PGASYNC_PIPELINE_IDLE;
 
 				/*
 				 * ... in cases when we're sending a pipeline-sync result,
@@ -3090,9 +3096,10 @@ pqPipelineProcessQueue(PGconn *conn)
 		case PGASYNC_READY:
 		case PGASYNC_READY_MORE:
 		case PGASYNC_BUSY:
+		case PGASYNC_IDLE:
 			/* client still has to process current query or results */
 			return;
-		case PGASYNC_IDLE:
+		case PGASYNC_PIPELINE_IDLE:
 			/* next query please */
 			break;
 	}
@@ -3100,7 +3107,10 @@ pqPipelineProcessQueue(PGconn *conn)
 	/* Nothing to do if not in pipeline mode, or queue is empty */
 	if (conn->pipelineStatus == PQ_PIPELINE_OFF ||
 		conn->cmd_queue_head == NULL)
+	{
+		conn->asyncStatus = PGASYNC_IDLE;
 		return;
+	}
 
 	/*
 	 * Reset the error state.  This and the next couple of steps correspond to
@@ -3193,6 +3203,7 @@ PQpipelineSync(PGconn *conn)
 		case PGASYNC_READY_MORE:
 		case PGASYNC_BUSY:
 		case PGASYNC_IDLE:
+		case PGASYNC_PIPELINE_IDLE:
 			/* OK to send sync */
 			break;
 	}
diff --git a/src/interfaces/libpq/fe-protocol3.c b/src/interfaces/libpq/fe-protocol3.c
index 10c76daf6e..0d60e8c5c0 100644
--- a/src/interfaces/libpq/fe-protocol3.c
+++ b/src/interfaces/libpq/fe-protocol3.c
@@ -158,18 +158,6 @@ pqParseInput3(PGconn *conn)
 			if (conn->asyncStatus != PGASYNC_IDLE)
 				return;
 
-			/*
-			 * We're also notionally not-IDLE when in pipeline mode the state
-			 * says "idle" (so we have completed receiving the results of one
-			 * query from the server and dispatched them to the application)
-			 * but another query is queued; yield back control to caller so
-			 * that they can initiate processing of the next query in the
-			 * queue.
-			 */
-			if (conn->pipelineStatus != PQ_PIPELINE_OFF &&
-				conn->cmd_queue_head != NULL)
-				return;
-
 			/*
 			 * Unexpected message in IDLE state; need to recover somehow.
 			 * ERROR messages are handled using the notice processor;
diff --git a/src/interfaces/libpq/libpq-int.h b/src/interfaces/libpq/libpq-int.h
index 3db6a17db4..7fcad1dd41 100644
--- a/src/interfaces/libpq/libpq-int.h
+++ b/src/interfaces/libpq/libpq-int.h
@@ -225,7 +225,8 @@ typedef enum
 								 * query */
 	PGASYNC_COPY_IN,			/* Copy In data transfer in progress */
 	PGASYNC_COPY_OUT,			/* Copy Out data transfer in progress */
-	PGASYNC_COPY_BOTH			/* Copy In/Out data transfer in progress */
+	PGASYNC_COPY_BOTH,			/* Copy In/Out data transfer in progress */
+	PGASYNC_PIPELINE_IDLE,		/* */
 } PGAsyncStatusType;
 
 /* Target server type (decoded value of target_session_attrs) */