From 2bf1906342ab9f6d4fd2ee2cd684cb4b9d727c1f Mon Sep 17 00:00:00 2001
From: Nguyen Ba Tam <nguyenbatam90@gmail.com>
Date: Wed, 10 Oct 2018 14:55:08 +0700
Subject: [PATCH] fix error when find penalties in 4 epoch ago

---
 consensus/posv/posv.go | 38 +++++++++++++++-----------------------
 eth/backend.go         |  2 ++
 2 files changed, 17 insertions(+), 23 deletions(-)

diff --git a/consensus/posv/posv.go b/consensus/posv/posv.go
index f87fd536cd..f9176ccd4a 100644
--- a/consensus/posv/posv.go
+++ b/consensus/posv/posv.go
@@ -652,22 +652,14 @@ func (c *Posv) Prepare(chain consensus.ChainReader, header *types.Header) error
 						}
 					}
 				}
-
-				var penBytes []byte
 				log.Debug("Penalty Info", "signers", penSigners, "number", number)
 				for _, penSigner := range penSigners {
-					// Convert number to byte.
-					penByte := common.LeftPadBytes([]byte(fmt.Sprintf("%d", penSigner)), common.AddressLength)
-					penBytes = append(penBytes, penByte...)
-				}
-				if len(penBytes) > 0 {
-					header.Penalties = penBytes
+					header.Penalties = append(header.Penalties, penSigner[:]...)
 				}
 			}
 		}
 
 		// Prevent penaltied signer in 4 epocs ago jump into signer list.
-		var preventSigners []common.Address
 		for i := 1; i <= 4; i++ {
 			checkEpoc := uint64(i) * c.config.Epoch
 			if number > checkEpoc {
@@ -676,26 +668,17 @@ func (c *Posv) Prepare(chain consensus.ChainReader, header *types.Header) error
 				prevEpocBlock := chain.GetBlock(prevHeader.Hash(), prevEpoc)
 				penalties := prevEpocBlock.Penalties()
 				if penalties != nil {
-					prevSigners := make([]common.Address, len(penalties)/common.AddressLength)
+					prevSigners := ExtractPenaltiesFromBytes(penalties)
 					if len(prevSigners) > 0 {
-						for _, signer := range prevSigners {
-							for _, prevSigner := range prevSigners {
-								if signer == prevSigner {
-									preventSigners = append(preventSigners, signer)
+						for i, signer := range signers {
+							for _, preventSigner := range prevSigners {
+								if signer == preventSigner {
+									signers = append(signers[:i], signers[i+1:]...)
 								}
 							}
 						}
 					}
 				}
-				if len(preventSigners) > 0 {
-					for i, signer := range signers {
-						for _, preventSigner := range preventSigners {
-							if signer == preventSigner {
-								signers = append(signers[:i], signers[i+1:]...)
-							}
-						}
-					}
-				}
 			}
 		}
 
@@ -912,3 +895,12 @@ func (c *Posv) GetMasternodesFromCheckpointHeader(preCheckpointHeader *types.Hea
 	}
 	return masternodes
 }
+
+// Extract validators from byte array.
+func ExtractPenaltiesFromBytes(bytePenalties []byte) []common.Address {
+	penalties := make([]common.Address, len(bytePenalties)/common.AddressLength)
+	for i := 0; i < len(penalties); i++ {
+		copy(penalties[i][:], bytePenalties[i*common.AddressLength:])
+	}
+	return penalties
+}
diff --git a/eth/backend.go b/eth/backend.go
index 793e602b4e..e70b8329c1 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -271,6 +271,8 @@ func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
 									}
 								}
 							}
+						} else {
+							break
 						}
 					}
 				}