From 10bfbae516c64226d284c8af929844e070fe7f1a Mon Sep 17 00:00:00 2001
From: HaoyangLiu <lhy.0318@163.com>
Date: Tue, 13 Nov 2018 19:43:30 +0800
Subject: [PATCH] Add RetreatLastBlock

---
 blockchain/store.go      | 13 +++++++++++++
 consensus/replay_test.go |  2 ++
 state/services.go        |  1 +
 3 files changed, 16 insertions(+)

diff --git a/blockchain/store.go b/blockchain/store.go
index f02d4facbcf..e8e2a4f7c78 100644
--- a/blockchain/store.go
+++ b/blockchain/store.go
@@ -186,6 +186,19 @@ func (bs *BlockStore) SaveBlock(block *types.Block, blockParts *types.PartSet, s
 	bs.db.SetSync(nil, nil)
 }
 
+func (bs *BlockStore) RetreatLastBlock() {
+	height := bs.height
+
+	bs.db.Delete(calcBlockMetaKey(height))
+	bs.db.Delete(calcBlockCommitKey(height-1))
+	bs.db.Delete(calcSeenCommitKey(height))
+
+	BlockStoreStateJSON{Height: height-1 }.Save(bs.db)
+
+	// Flush
+	bs.db.SetSync(nil, nil)
+}
+
 func (bs *BlockStore) saveBlockPart(height int64, index int, part *types.Part) {
 	if height != bs.Height()+1 {
 		cmn.PanicSanity(cmn.Fmt("BlockStore can only save contiguous blocks. Wanted %v, got %v", bs.Height()+1, height))
diff --git a/consensus/replay_test.go b/consensus/replay_test.go
index fa0ec040897..b7821ee1c6a 100644
--- a/consensus/replay_test.go
+++ b/consensus/replay_test.go
@@ -629,6 +629,8 @@ func (bs *mockBlockStore) LoadBlockMeta(height int64) *types.BlockMeta {
 func (bs *mockBlockStore) LoadBlockPart(height int64, index int) *types.Part { return nil }
 func (bs *mockBlockStore) SaveBlock(block *types.Block, blockParts *types.PartSet, seenCommit *types.Commit) {
 }
+func (bs *mockBlockStore) RetreatLastBlock() {
+}
 func (bs *mockBlockStore) LoadBlockCommit(height int64) *types.Commit {
 	return bs.commits[height-1]
 }
diff --git a/state/services.go b/state/services.go
index c51fa97521a..aeba9fd2fbd 100644
--- a/state/services.go
+++ b/state/services.go
@@ -65,6 +65,7 @@ type BlockStoreRPC interface {
 type BlockStore interface {
 	BlockStoreRPC
 	SaveBlock(block *types.Block, blockParts *types.PartSet, seenCommit *types.Commit)
+	RetreatLastBlock()
 }
 
 //-----------------------------------------------------------------------------------------------------