Problem: memiavl result is different when replaying write-ahead-log

CHANGELOG.md

@@ -30,6 +30,7 @@
 - [#1075](https://github.com/crypto-org-chain/cronos/pull/1075) Add missing close in memiavl to avoid resource leaks.
 - [#1073](https://github.com/crypto-org-chain/cronos/pull/1073) memiavl automatically truncate corrupted wal tail.
 - [#1087](https://github.com/crypto-org-chain/cronos/pull/1087) memiavl fix LastCommitID when memiavl db not loaded.
+- [#1088](https://github.com/crypto-org-chain/cronos/pull/1088) memiavl fix empty value in write-ahead-log replaying.
 
 ### Features
 

app/app.go

@@ -999,7 +999,7 @@ func VerifyAddressFormat(bz []byte) error {
 // Close will be called in graceful shutdown in start cmd
 func (app *App) Close() error {
 	if cms, ok := app.CommitMultiStore().(*memiavlrootmulti.Store); ok {
-		return cms.WaitAsyncCommit()
+		return cms.Close()
 	}
 
 	return nil

memiavl/db.go

@@ -399,6 +399,10 @@ func (db *DB) WaitAsyncCommit() error {
 	db.mtx.Lock()
 	defer db.mtx.Unlock()
 
+	return db.waitAsyncCommit()
+}
+
+func (db *DB) waitAsyncCommit() error {
 	if db.walChan == nil {
 		return nil
 	}
@@ -547,16 +551,7 @@ func (db *DB) Close() error {
 	db.mtx.Lock()
 	defer db.mtx.Unlock()
 
-	var walErr error
-	if db.walChan != nil {
-		close(db.walChan)
-		walErr = <-db.walQuit
-
-		db.walChan = nil
-		db.walQuit = nil
-	}
-
-	return errors.Join(db.MultiTree.Close(), db.wal.Close(), walErr)
+	return errors.Join(db.waitAsyncCommit(), db.MultiTree.Close(), db.wal.Close())
 }
 
 // TreeByName wraps MultiTree.TreeByName to add a lock.

memiavl/db_test.go

@@ -283,3 +283,33 @@ func TestWalIndexConversion(t *testing.T) {
 		require.Equal(t, tc.version, walVersion(tc.index, tc.initialVersion))
 	}
 }
+
+func TestEmptyValue(t *testing.T) {
+	dir := t.TempDir()
+	db, err := Load(dir, Options{InitialStores: []string{"test"}, CreateIfMissing: true, ZeroCopy: true})
+	require.NoError(t, err)
+
+	_, _, err = db.Commit([]*NamedChangeSet{
+		{Name: "test", Changeset: iavl.ChangeSet{
+			Pairs: []*iavl.KVPair{
+				{Key: []byte("hello1"), Value: []byte("")},
+				{Key: []byte("hello2"), Value: []byte("")},
+				{Key: []byte("hello3"), Value: []byte("")},
+			},
+		}},
+	})
+	require.NoError(t, err)
+	hash, version, err := db.Commit([]*NamedChangeSet{
+		{Name: "test", Changeset: iavl.ChangeSet{
+			Pairs: []*iavl.KVPair{{Key: []byte("hello1"), Delete: true}},
+		}},
+	})
+	require.NoError(t, err)
+
+	require.NoError(t, db.Close())
+
+	db, err = Load(dir, Options{ZeroCopy: true})
+	require.NoError(t, err)
+	require.Equal(t, version, db.Version())
+	require.Equal(t, hash, db.LastCommitInfo().CommitID().Hash)
+}

memiavl/tree.go

@@ -123,6 +123,10 @@ func (t *Tree) ApplyChangeSet(changeSet iavl.ChangeSet, updateHash bool) ([]byte
 }
 
 func (t *Tree) set(key, value []byte) {
+	if value == nil {
+		// the value could be nil when replaying changes from write-ahead-log because of protobuf decoding
+		value = []byte{}
+	}
 	t.root, _ = setRecursive(t.root, key, value, t.version+1, t.cowVersion)
 	t.cache.Add(&cacheNode{key, value})
 }

store/rootmulti/store.go

@@ -108,8 +108,8 @@ func (rs *Store) Commit() types.CommitID {
 	return rs.lastCommitInfo.CommitID()
 }
 
-func (rs *Store) WaitAsyncCommit() error {
-	return rs.db.WaitAsyncCommit()
+func (rs *Store) Close() error {
+	return rs.db.Close()
 }
 
 // Implements interface Committer