Avoid hanging on exit in pglogical_receiver

Author: knizhnik

contrib/mmts/multimaster.c

@@ -2325,7 +2325,7 @@ void MtmReceiverStarted(int nodeId)
 MtmReplicationMode MtmGetReplicationMode(int nodeId)
 {
 	bool recovery = false;
-	while (Mtm->status != MTM_CONNECTED && Mtm->status != MTM_ONLINE) { 		
+	if (Mtm->status != MTM_CONNECTED && Mtm->status != MTM_ONLINE) { 		
 		MTM_LOG2("%d: receiver slot mode %s", MyProcPid, MtmNodeStatusMnem[Mtm->status]);
 		if (Mtm->status == MTM_RECOVERY) { 
 			recovery = true;
@@ -2342,6 +2342,7 @@ MtmReplicationMode MtmGetReplicationMode(int nodeId)
 		}
 		/* delay opening of other slots until recovery is completed */
 		MtmSleep(STATUS_POLL_DELAY);
+		return REPLMODE_UNKNOWN;
 	}
 	if (recovery) { 
 		MTM_LOG1("Recreate replication slot for node %d after end of recovery", nodeId);

contrib/mmts/multimaster.h

@@ -117,6 +117,7 @@ typedef enum
 
 typedef enum
 {
+	REPLMODE_UNKNOWN,    /* receiver should wait */
 	REPLMODE_RECOVERED,  /* recovery of node is completed so drop old slot and restart replication from the current position in WAL */
 	REPLMODE_RECOVERY,   /* perform recorvery of the node by applying all data from the slot from specified point */
 	REPLMODE_NORMAL      /* normal mode: use existed slot or create new one and start receiving data from it from the specified position */