From 1cc479dbf8cd3ad356cf0d4a6076cdcf4269a099 Mon Sep 17 00:00:00 2001
From: stasatdaglabs <39559713+stasatdaglabs@users.noreply.github.com>
Date: Wed, 1 May 2019 18:01:58 +0300
Subject: [PATCH] [NOD-152] Netsync correctly syncs only 500 first blocks
 (#276)

* [NOD-152] Stopped pushBlockMsg from sending tip inv to syncing nodes.

* [NOD-152] Fixed restartSyncIfNeeded not restarting if sync is needed.

* [NOD-152] Removed continueHash, as it is no longer required.
---
 netsync/manager.go |  2 ++
 server/p2p/p2p.go  | 33 +--------------------------------
 2 files changed, 3 insertions(+), 32 deletions(-)

diff --git a/netsync/manager.go b/netsync/manager.go
index 0e0319c65..adce4c2eb 100644
--- a/netsync/manager.go
+++ b/netsync/manager.go
@@ -496,6 +496,8 @@ func (sm *SyncManager) restartSyncIfNeeded() {
 			}
 		}
 	}
+
+	sm.syncPeer = nil
 	sm.startSync()
 }
 
diff --git a/server/p2p/p2p.go b/server/p2p/p2p.go
index 2c7555dbd..cdc814d2d 100644
--- a/server/p2p/p2p.go
+++ b/server/p2p/p2p.go
@@ -160,7 +160,6 @@ type Peer struct {
 	connReq         *connmgr.ConnReq
 	server          *Server
 	persistent      bool
-	continueHash    *daghash.Hash
 	relayMtx        sync.Mutex
 	DisableRelayTx  bool
 	sentAddrs       bool
@@ -713,15 +712,6 @@ func (sp *Peer) OnGetBlocks(_ *peer.Peer, msg *wire.MsgGetBlocks) {
 
 	// Send the inventory message if there is anything to send.
 	if len(invMsg.InvList) > 0 {
-		invListLen := len(invMsg.InvList)
-		if invListLen == wire.MaxBlocksPerMsg {
-			// Intentionally use a copy of the final hash so there
-			// is not a reference into the inventory slice which
-			// would prevent the entire slice from being eligible
-			// for GC as soon as it's sent.
-			continueHash := invMsg.InvList[invListLen-1].Hash
-			sp.continueHash = continueHash
-		}
 		sp.QueueMessage(invMsg, nil)
 	}
 }
@@ -1318,29 +1308,8 @@ func (s *Server) pushBlockMsg(sp *Peer, hash *daghash.Hash, doneChan chan<- stru
 		<-waitChan
 	}
 
-	// We only send the channel for this message if we aren't sending
-	// an inv straight after.
-	var dc chan<- struct{}
-	continueHash := sp.continueHash
-	sendInv := continueHash != nil && continueHash.IsEqual(hash)
-	if !sendInv {
-		dc = doneChan
-	}
-	sp.QueueMessage(&msgBlock, dc)
+	sp.QueueMessage(&msgBlock, doneChan)
 
-	// When the peer requests the final block that was advertised in
-	// response to a getblocks message which requested more blocks than
-	// would fit into a single message, send it a new inventory message
-	// to trigger it to issue another getblocks message for the next
-	// batch of inventory.
-	if sendInv {
-		highestTipHash := sp.server.DAG.HighestTipHash()
-		invMsg := wire.NewMsgInvSizeHint(1)
-		iv := wire.NewInvVect(wire.InvTypeBlock, highestTipHash)
-		invMsg.AddInvVect(iv)
-		sp.QueueMessage(invMsg, doneChan)
-		sp.continueHash = nil
-	}
 	return nil
 }