From b5b83db450974f70f4bc25f280cc6ec9193f8e19 Mon Sep 17 00:00:00 2001
From: Felix Lange <fjl@twurst.com>
Date: Wed, 18 Mar 2015 13:36:48 +0100
Subject: [PATCH] core: use package rlp to encode blocks

This also changes the chain export format so there is no
enclosing list around the blocks, which enables streaming export.
---
 cmd/utils/cmd.go      | 37 ++++++++++++++++++++++---------------
 core/chain_manager.go | 27 ++++++++++++---------------
 2 files changed, 34 insertions(+), 30 deletions(-)

diff --git a/cmd/utils/cmd.go b/cmd/utils/cmd.go
index 74fd5334e9..66e89abefa 100644
--- a/cmd/utils/cmd.go
+++ b/cmd/utils/cmd.go
@@ -23,14 +23,15 @@ package utils
 
 import (
 	"fmt"
+	"io"
 	"os"
 	"os/signal"
 	"regexp"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/eth"
-	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/rlp"
 )
@@ -152,29 +153,35 @@ func ImportChain(chainmgr *core.ChainManager, fn string) error {
 	}
 	defer fh.Close()
 
-	var blocks types.Blocks
-	if err := rlp.Decode(fh, &blocks); err != nil {
-		return err
-	}
-
 	chainmgr.Reset()
-	if err := chainmgr.InsertChain(blocks); err != nil {
-		return err
+	stream := rlp.NewStream(fh)
+	var i int
+	for ; ; i++ {
+		var b types.Block
+		err := stream.Decode(&b)
+		if err == io.EOF {
+			break
+		} else if err != nil {
+			return fmt.Errorf("at block %d: %v", i, err)
+		}
+		if err := chainmgr.InsertChain(types.Blocks{b}); err != nil {
+			return fmt.Errorf("invalid block %d: %v", i, err)
+		}
 	}
-	fmt.Printf("imported %d blocks\n", len(blocks))
-
+	fmt.Printf("imported %d blocks\n", i)
 	return nil
 }
 
 func ExportChain(chainmgr *core.ChainManager, fn string) error {
 	fmt.Printf("exporting blockchain '%s'\n", fn)
-
-	data := chainmgr.Export()
-
-	if err := common.WriteFile(fn, data); err != nil {
+	fh, err := os.OpenFile(fn, os.O_WRONLY|os.O_TRUNC, os.ModePerm)
+	if err != nil {
+		return err
+	}
+	defer fh.Close()
+	if err := chainmgr.Export(fh); err != nil {
 		return err
 	}
 	fmt.Printf("exported blockchain\n")
-
 	return nil
 }
diff --git a/core/chain_manager.go b/core/chain_manager.go
index 5316a34230..0608054285 100644
--- a/core/chain_manager.go
+++ b/core/chain_manager.go
@@ -3,6 +3,7 @@ package core
 import (
 	"bytes"
 	"fmt"
+	"io"
 	"math/big"
 	"sync"
 
@@ -254,22 +255,20 @@ func (bc *ChainManager) ResetWithGenesisBlock(gb *types.Block) {
 	bc.currentBlock = bc.genesisBlock
 }
 
-func (self *ChainManager) Export() []byte {
+// Export writes the active chain to the given writer.
+func (self *ChainManager) Export(w io.Writer) error {
 	self.mu.RLock()
 	defer self.mu.RUnlock()
-
 	chainlogger.Infof("exporting %v blocks...\n", self.currentBlock.Header().Number)
-
-	blocks := make([]*types.Block, int(self.currentBlock.NumberU64())+1)
 	for block := self.currentBlock; block != nil; block = self.GetBlock(block.Header().ParentHash) {
-		blocks[block.NumberU64()] = block
+		if err := block.EncodeRLP(w); err != nil {
+			return err
+		}
 	}
-
-	return common.Encode(blocks)
+	return nil
 }
 
 func (bc *ChainManager) insert(block *types.Block) {
-	//encodedBlock := common.Encode(block)
 	bc.blockDb.Put([]byte("LastBlock"), block.Hash().Bytes())
 	bc.currentBlock = block
 	bc.lastBlockHash = block.Hash()
@@ -279,10 +278,9 @@ func (bc *ChainManager) insert(block *types.Block) {
 }
 
 func (bc *ChainManager) write(block *types.Block) {
-	encodedBlock := common.Encode(block.RlpDataForStorage())
-
+	enc, _ := rlp.EncodeToBytes((*types.StorageBlock)(block))
 	key := append(blockHashPre, block.Hash().Bytes()...)
-	bc.blockDb.Put(key, encodedBlock)
+	bc.blockDb.Put(key, enc)
 }
 
 // Accessors
@@ -324,13 +322,12 @@ func (self *ChainManager) GetBlock(hash common.Hash) *types.Block {
 	if len(data) == 0 {
 		return nil
 	}
-	var block types.Block
+	var block types.StorageBlock
 	if err := rlp.Decode(bytes.NewReader(data), &block); err != nil {
-		fmt.Println(err)
+		chainlogger.Errorf("invalid block RLP for hash %x: %v", hash, err)
 		return nil
 	}
-
-	return &block
+	return (*types.Block)(&block)
 }
 
 func (self *ChainManager) GetBlockByNumber(num uint64) *types.Block {