core: apply feedback from Guillaume

core/genesis.go

@@ -80,16 +80,33 @@ func (ga *GenesisAlloc) UnmarshalJSON(data []byte) error {
 	return nil
 }
 
-// flush adds allocated genesis accounts into a fresh new statedb and
-// commit the state changes into the given database handler.
-func (ga *GenesisAlloc) flush(db ethdb.Database) (common.Hash, error) {
-	statedb, err := state.New(common.Hash{}, state.NewDatabase(db), nil)
+// deriveHash computes the state root according to the genesis specification.
+func (ga *GenesisAlloc) deriveHash() (common.Hash, error) {
+	// Create an ephemeral in-memory database for computing hash,
+	// all the derived states won't be leaked into disk for sure.
+	db := state.NewDatabase(rawdb.NewMemoryDatabase())
+	statedb, err := state.New(common.Hash{}, db, nil)
 	if err != nil {
 		return common.Hash{}, err
 	}
-	// Short circuit if nothing to flush
-	if len(*ga) == 0 {
-		return statedb.Commit(false)
+	for addr, account := range *ga {
+		statedb.AddBalance(addr, account.Balance)
+		statedb.SetCode(addr, account.Code)
+		statedb.SetNonce(addr, account.Nonce)
+		for key, value := range account.Storage {
+			statedb.SetState(addr, key, value)
+		}
+	}
+	return statedb.Commit(false)
+}
+
+// flush is very similar with deriveHash, but the main difference is
+// all the generated states will be persisted into the given database.
+// Also, the genesis state specification will be flushed as well.
+func (ga *GenesisAlloc) flush(db ethdb.Database) error {
+	statedb, err := state.New(common.Hash{}, state.NewDatabase(db), nil)
+	if err != nil {
+		return err
 	}
 	for addr, account := range *ga {
 		statedb.AddBalance(addr, account.Balance)
@@ -101,31 +118,26 @@ func (ga *GenesisAlloc) flush(db ethdb.Database) (common.Hash, error) {
 	}
 	root, err := statedb.Commit(false)
 	if err != nil {
-		return common.Hash{}, err
+		return err
 	}
 	err = statedb.Database().TrieDB().Commit(root, true, nil)
 	if err != nil {
-		return common.Hash{}, err
+		return err
 	}
-	return root, nil
-}
-
-// write writes the json marshaled genesis state into database
-// with the given block hash as the unique identifier.
-func (ga *GenesisAlloc) write(db ethdb.KeyValueWriter, hash common.Hash) error {
+	// Marshal the genesis state specification and persist.
 	blob, err := json.Marshal(ga)
 	if err != nil {
 		return err
 	}
-	rawdb.WriteGenesisState(db, hash, blob)
+	rawdb.WriteGenesisStateSpec(db, root, blob)
 	return nil
 }
 
 // CommitGenesisState loads the stored genesis state with the given block
 // hash and commits them into the given database handler.
 func CommitGenesisState(db ethdb.Database, hash common.Hash) error {
 	var alloc GenesisAlloc
-	blob := rawdb.ReadGenesisState(db, hash)
+	blob := rawdb.ReadGenesisStateSpec(db, hash)
 	if len(blob) != 0 {
 		if err := alloc.UnmarshalJSON(blob); err != nil {
 			return err
@@ -155,8 +167,7 @@ func CommitGenesisState(db ethdb.Database, hash common.Hash) error {
 			return errors.New("not found")
 		}
 	}
-	_, err := alloc.flush(db)
-	return err
+	return alloc.flush(db)
 }
 
 // GenesisAccount is an account in the state of the genesis block.
@@ -351,13 +362,9 @@ func (g *Genesis) configOrDefault(ghash common.Hash) *params.ChainConfig {
 	}
 }
 
-// toBlock creates the genesis block and writes state of a genesis specification
-// to the given database (or discards it if nil).
-func (g *Genesis) toBlock(db ethdb.Database) *types.Block {
-	if db == nil {
-		db = rawdb.NewMemoryDatabase()
-	}
-	root, err := g.Alloc.flush(db)
+// ToBlock returns the genesis block according to genesis specification.
+func (g *Genesis) ToBlock() *types.Block {
+	root, err := g.Alloc.deriveHash()
 	if err != nil {
 		panic(err)
 	}
@@ -391,15 +398,10 @@ func (g *Genesis) toBlock(db ethdb.Database) *types.Block {
 	return types.NewBlock(head, nil, nil, nil, trie.NewStackTrie(nil))
 }
 
-// ToBlock returns the genesis block according to genesis specification.
-func (g *Genesis) ToBlock() *types.Block {
-	return g.toBlock(nil)
-}
-
 // Commit writes the block and state of a genesis specification to the database.
 // The block is committed as the canonical head block.
 func (g *Genesis) Commit(db ethdb.Database) (*types.Block, error) {
-	block := g.toBlock(db)
+	block := g.ToBlock()
 	if block.Number().Sign() != 0 {
 		return nil, errors.New("can't commit genesis block with number > 0")
 	}
@@ -413,7 +415,10 @@ func (g *Genesis) Commit(db ethdb.Database) (*types.Block, error) {
 	if config.Clique != nil && len(block.Extra()) < 32+crypto.SignatureLength {
 		return nil, errors.New("can't start clique chain without signers")
 	}
-	if err := g.Alloc.write(db, block.Hash()); err != nil {
+	// All the checks has passed, flush the states derived from the genesis
+	// specification as well as the specification itself into the provided
+	// database.
+	if err := g.Alloc.flush(db); err != nil {
 		return nil, err
 	}
 	rawdb.WriteTd(db, block.Hash(), block.NumberU64(), block.Difficulty())

core/genesis_test.go

@@ -217,12 +217,12 @@ func TestReadWriteGenesisAlloc(t *testing.T) {
 			{1}: {Balance: big.NewInt(1), Storage: map[common.Hash]common.Hash{{1}: {1}}},
 			{2}: {Balance: big.NewInt(2), Storage: map[common.Hash]common.Hash{{2}: {2}}},
 		}
-		hash = common.HexToHash("0xdeadbeef")
+		hash, _ = alloc.deriveHash()
 	)
-	alloc.write(db, hash)
+	alloc.flush(db)
 
 	var reload GenesisAlloc
-	err := reload.UnmarshalJSON(rawdb.ReadGenesisState(db, hash))
+	err := reload.UnmarshalJSON(rawdb.ReadGenesisStateSpec(db, hash))
 	if err != nil {
 		t.Fatalf("Failed to load genesis state %v", err)
 	}

core/rawdb/accessors_metadata.go

@@ -81,15 +81,16 @@ func WriteChainConfig(db ethdb.KeyValueWriter, hash common.Hash, cfg *params.Cha
 	}
 }
 
-// ReadGenesisState retrieves the genesis state based on the given genesis hash.
-func ReadGenesisState(db ethdb.KeyValueReader, hash common.Hash) []byte {
-	data, _ := db.Get(genesisKey(hash))
+// ReadGenesisStateSpec retrieves the genesis state specification based on the
+// given genesis hash.
+func ReadGenesisStateSpec(db ethdb.KeyValueReader, hash common.Hash) []byte {
+	data, _ := db.Get(genesisStateSpecKey(hash))
 	return data
 }
 
-// WriteGenesisState writes the genesis state into the disk.
-func WriteGenesisState(db ethdb.KeyValueWriter, hash common.Hash, data []byte) {
-	if err := db.Put(genesisKey(hash), data); err != nil {
+// WriteGenesisStateSpec writes the genesis state specification into the disk.
+func WriteGenesisStateSpec(db ethdb.KeyValueWriter, hash common.Hash, data []byte) {
+	if err := db.Put(genesisStateSpecKey(hash), data); err != nil {
 		log.Crit("Failed to store genesis state", "err", err)
 	}
 }

core/rawdb/schema.go

@@ -247,7 +247,7 @@ func configKey(hash common.Hash) []byte {
 	return append(configPrefix, hash.Bytes()...)
 }
 
-// genesisKey = genesisPrefix + hash
-func genesisKey(hash common.Hash) []byte {
+// genesisStateSpecKey = genesisPrefix + hash
+func genesisStateSpecKey(hash common.Hash) []byte {
 	return append(genesisPrefix, hash.Bytes()...)
 }