From 7b1c3050002441f42fff7b74aca5512de88e7c18 Mon Sep 17 00:00:00 2001
From: Anna Shaleva <shaleva.ann@nspcc.ru>
Date: Fri, 31 Jul 2020 14:51:51 +0300
Subject: [PATCH] network: fix handleGetBlockByIndexCmd method

It returned an error in case if block wasn't found (it might be when our
chain is lower). Fixed. It also should return all requested blocks, not
the first one.
---
 pkg/network/server.go | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/pkg/network/server.go b/pkg/network/server.go
index 6df448d27..e681f335d 100644
--- a/pkg/network/server.go
+++ b/pkg/network/server.go
@@ -616,12 +616,18 @@ func (s *Server) handleGetBlockByIndexCmd(p Peer, gbd *payload.GetBlockByIndex)
 		count = payload.MaxHashesCount
 	}
 	for i := gbd.IndexStart; i < gbd.IndexStart+uint32(count); i++ {
-		b, err := s.chain.GetBlock(s.chain.GetHeaderHash(int(i)))
+		hash := s.chain.GetHeaderHash(int(i))
+		if hash.Equals(util.Uint256{}) {
+			break
+		}
+		b, err := s.chain.GetBlock(hash)
 		if err != nil {
-			return err
+			break
 		}
 		msg := NewMessage(CMDBlock, b)
-		return p.EnqueueP2PMessage(msg)
+		if err = p.EnqueueP2PMessage(msg); err != nil {
+			return err
+		}
 	}
 	return nil
 }