add some code

Author: wugang33

README.md

@@ -18,10 +18,15 @@
 	- [区块链索引 chain_indexer源码分析](/core-chain_indexer源码解析.md)
 	- [布隆过滤器索引 bloombits源码分析](/core-bloombits源码分析.md)
 	- [以太坊的trie树管理 回滚等操作 state源码分析](/core-state源码分析.md)
+	- [交易执行和处理部分源码分析](/core-state-process源码分析.md)
 	- vm 虚拟机源码分析
 		- [虚拟机堆栈和内存数据结构分析](/core-vm-stack-memory源码分析.md)
 		- [虚拟机指令,跳转表,解释器源码分析](/core-vm-jumptable-instruction.md)
 		- [虚拟机源码分析](/core-vm源码分析.md)
-
+	- 待确认交易池的管理txPool
+		- [交易执行和处理部分源码分析](/core-txlist交易池的一些数据结构源码分析.md)
+		- [交易执行和处理部分源码分析](/core-txpool交易池源码分析.md)
+	- [创世区块的源码分析](/core-genesis创世区块源码分析.md)
+	- [blockchain 源码分析](/core-blockchain源码分析.md)
 
 

core-blockchain源码分析.md

@@ -0,0 +1,259 @@
+genesis 是创世区块的意思. 一个区块链就是从同一个创世区块开始,通过规则形成的.不同的网络有不同的创世区块, 主网络和测试网路的创世区块是不同的.
+
+这个模块根据传入的genesis的初始值和database，来设置genesis的状态，如果不存在创世区块，那么在database里面创建它。
+
+数据结构
+	
+	// Genesis specifies the header fields, state of a genesis block. It also defines hard
+	// fork switch-over blocks through the chain configuration.
+	// Genesis指定header的字段，起始块的状态。 它还通过配置来定义硬叉切换块。
+	type Genesis struct {
+		Config     *params.ChainConfig `json:"config"`
+		Nonce      uint64              `json:"nonce"`
+		Timestamp  uint64              `json:"timestamp"`
+		ExtraData  []byte              `json:"extraData"`
+		GasLimit   uint64              `json:"gasLimit"   gencodec:"required"`
+		Difficulty *big.Int            `json:"difficulty" gencodec:"required"`
+		Mixhash    common.Hash         `json:"mixHash"`
+		Coinbase   common.Address      `json:"coinbase"`
+		Alloc      GenesisAlloc        `json:"alloc"      gencodec:"required"`
+	
+		// These fields are used for consensus tests. Please don't use them
+		// in actual genesis blocks.
+		Number     uint64      `json:"number"`
+		GasUsed    uint64      `json:"gasUsed"`
+		ParentHash common.Hash `json:"parentHash"`
+	}
+	
+	// GenesisAlloc specifies the initial state that is part of the genesis block.
+	// GenesisAlloc 指定了最开始的区块的初始状态.
+	type GenesisAlloc map[common.Address]GenesisAccount
+
+
+SetupGenesisBlock,
+	
+	// SetupGenesisBlock writes or updates the genesis block in db.
+	// 
+	// The block that will be used is:
+	//
+	//                          genesis == nil       genesis != nil
+	//                       +------------------------------------------
+	//     db has no genesis |  main-net default  |  genesis
+	//     db has genesis    |  from DB           |  genesis (if compatible)
+	//
+	// The stored chain configuration will be updated if it is compatible (i.e. does not
+	// specify a fork block below the local head block). In case of a conflict, the
+	// error is a *params.ConfigCompatError and the new, unwritten config is returned.
+	// 如果存储的区块链配置不兼容那么会被更新(). 为了避免发生冲突,会返回一个错误,并且新的配置和原来的配置会返回.
+	// The returned chain configuration is never nil.
+
+	// genesis 如果是 testnet dev 或者是 rinkeby 模式， 那么不为nil。如果是mainnet或者是私有链接。那么为空
+	func SetupGenesisBlock(db ethdb.Database, genesis *Genesis) (*params.ChainConfig, common.Hash, error) {
+		if genesis != nil && genesis.Config == nil {
+			return params.AllProtocolChanges, common.Hash{}, errGenesisNoConfig
+		}
+	
+		// Just commit the new block if there is no stored genesis block.
+		stored := GetCanonicalHash(db, 0) //获取genesis对应的区块
+		if (stored == common.Hash{}) { //如果没有区块 最开始启动geth会进入这里。
+			if genesis == nil { 
+				//如果genesis是nil 而且stored也是nil 那么使用主网络
+				// 如果是test  dev  rinkeby 那么genesis不为空 会设置为各自的genesis
+				log.Info("Writing default main-net genesis block")
+				genesis = DefaultGenesisBlock()
+			} else { // 否则使用配置的区块
+				log.Info("Writing custom genesis block")
+			}
+			// 写入数据库
+			block, err := genesis.Commit(db)
+			return genesis.Config, block.Hash(), err
+		}
+	
+		// Check whether the genesis block is already written.
+		if genesis != nil { //如果genesis存在而且区块也存在 那么对比这两个区块是否相同
+			block, _ := genesis.ToBlock()
+			hash := block.Hash()
+			if hash != stored {
+				return genesis.Config, block.Hash(), &GenesisMismatchError{stored, hash}
+			}
+		}
+	
+		// Get the existing chain configuration.
+		// 获取当前存在的区块链的genesis配置
+		newcfg := genesis.configOrDefault(stored)
+		// 获取当前的区块链的配置
+		storedcfg, err := GetChainConfig(db, stored)
+		if err != nil {
+			if err == ErrChainConfigNotFound {
+				// This case happens if a genesis write was interrupted.
+				log.Warn("Found genesis block without chain config")
+				err = WriteChainConfig(db, stored, newcfg)
+			}
+			return newcfg, stored, err
+		}
+		// Special case: don't change the existing config of a non-mainnet chain if no new
+		// config is supplied. These chains would get AllProtocolChanges (and a compat error)
+		// if we just continued here.
+		// 特殊情况：如果没有提供新的配置，请不要更改非主网链的现有配置。 
+		// 如果我们继续这里，这些链会得到AllProtocolChanges（和compat错误）。
+		if genesis == nil && stored != params.MainnetGenesisHash {
+			return storedcfg, stored, nil   // 如果是私有链接会从这里退出。
+		}
+	
+		// Check config compatibility and write the config. Compatibility errors
+		// are returned to the caller unless we're already at block zero.
+		// 检查配置的兼容性,除非我们在区块0,否则返回兼容性错误.
+		height := GetBlockNumber(db, GetHeadHeaderHash(db))
+		if height == missingNumber {
+			return newcfg, stored, fmt.Errorf("missing block number for head header hash")
+		}
+		compatErr := storedcfg.CheckCompatible(newcfg, height)
+		// 如果区块已经写入数据了,那么就不能更改genesis配置了
+		if compatErr != nil && height != 0 && compatErr.RewindTo != 0 {
+			return newcfg, stored, compatErr
+		}
+		// 如果是主网络会从这里退出。
+		return newcfg, stored, WriteChainConfig(db, stored, newcfg)
+	}
+
+
+ToBlock, 这个方法使用genesis的数据，使用基于内存的数据库，然后创建了一个block并返回。
+	
+	
+	// ToBlock creates the block and state of a genesis specification.
+	func (g *Genesis) ToBlock() (*types.Block, *state.StateDB) {
+		db, _ := ethdb.NewMemDatabase()
+		statedb, _ := state.New(common.Hash{}, state.NewDatabase(db))
+		for addr, account := range g.Alloc {
+			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)
+			}
+		}
+		root := statedb.IntermediateRoot(false)
+		head := &types.Header{
+			Number:     new(big.Int).SetUint64(g.Number),
+			Nonce:      types.EncodeNonce(g.Nonce),
+			Time:       new(big.Int).SetUint64(g.Timestamp),
+			ParentHash: g.ParentHash,
+			Extra:      g.ExtraData,
+			GasLimit:   new(big.Int).SetUint64(g.GasLimit),
+			GasUsed:    new(big.Int).SetUint64(g.GasUsed),
+			Difficulty: g.Difficulty,
+			MixDigest:  g.Mixhash,
+			Coinbase:   g.Coinbase,
+			Root:       root,
+		}
+		if g.GasLimit == 0 {
+			head.GasLimit = params.GenesisGasLimit
+		}
+		if g.Difficulty == nil {
+			head.Difficulty = params.GenesisDifficulty
+		}
+		return types.NewBlock(head, nil, nil, nil), statedb
+	}
+
+Commit方法和MustCommit方法, Commit方法把给定的genesis的block和state写入数据库， 这个block被认为是规范的区块链头。
+	
+	// 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, statedb := g.ToBlock()
+		if block.Number().Sign() != 0 {
+			return nil, fmt.Errorf("can't commit genesis block with number > 0")
+		}
+		if _, err := statedb.CommitTo(db, false); err != nil {
+			return nil, fmt.Errorf("cannot write state: %v", err)
+		}
+		// 写入总难度
+		if err := WriteTd(db, block.Hash(), block.NumberU64(), g.Difficulty); err != nil {
+			return nil, err
+		}
+		// 写入区块
+		if err := WriteBlock(db, block); err != nil {
+			return nil, err
+		}
+		// 写入区块收据
+		if err := WriteBlockReceipts(db, block.Hash(), block.NumberU64(), nil); err != nil {
+			return nil, err
+		}
+		// 写入   headerPrefix + num (uint64 big endian) + numSuffix -> hash
+		if err := WriteCanonicalHash(db, block.Hash(), block.NumberU64()); err != nil {
+			return nil, err
+		}
+		// 写入  "LastBlock" -> hash
+		if err := WriteHeadBlockHash(db, block.Hash()); err != nil {
+			return nil, err
+		}
+		// 写入 "LastHeader" -> hash
+		if err := WriteHeadHeaderHash(db, block.Hash()); err != nil {
+			return nil, err
+		}
+		config := g.Config
+		if config == nil {
+			config = params.AllProtocolChanges
+		}
+		// 写入 ethereum-config-hash -> config
+		return block, WriteChainConfig(db, block.Hash(), config)
+	}
+	
+	// MustCommit writes the genesis block and state to db, panicking on error.
+	// The block is committed as the canonical head block.
+	func (g *Genesis) MustCommit(db ethdb.Database) *types.Block {
+		block, err := g.Commit(db)
+		if err != nil {
+			panic(err)
+		}
+		return block
+	}
+
+返回各种模式的默认Genesis
+	
+	// DefaultGenesisBlock returns the Ethereum main net genesis block.
+	func DefaultGenesisBlock() *Genesis {
+		return &Genesis{
+			Config:     params.MainnetChainConfig,
+			Nonce:      66,
+			ExtraData:  hexutil.MustDecode("0x11bbe8db4e347b4e8c937c1c8370e4b5ed33adb3db69cbdb7a38e1e50b1b82fa"),
+			GasLimit:   5000,
+			Difficulty: big.NewInt(17179869184),
+			Alloc:      decodePrealloc(mainnetAllocData),
+		}
+	}
+	
+	// DefaultTestnetGenesisBlock returns the Ropsten network genesis block.
+	func DefaultTestnetGenesisBlock() *Genesis {
+		return &Genesis{
+			Config:     params.TestnetChainConfig,
+			Nonce:      66,
+			ExtraData:  hexutil.MustDecode("0x3535353535353535353535353535353535353535353535353535353535353535"),
+			GasLimit:   16777216,
+			Difficulty: big.NewInt(1048576),
+			Alloc:      decodePrealloc(testnetAllocData),
+		}
+	}
+	
+	// DefaultRinkebyGenesisBlock returns the Rinkeby network genesis block.
+	func DefaultRinkebyGenesisBlock() *Genesis {
+		return &Genesis{
+			Config:     params.RinkebyChainConfig,
+			Timestamp:  1492009146,
+			ExtraData:  hexutil.MustDecode("0x52657370656374206d7920617574686f7269746168207e452e436172746d616e42eb768f2244c8811c63729a21a3569731535f067ffc57839b00206d1ad20c69a1981b489f772031b279182d99e65703f0076e4812653aab85fca0f00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"),
+			GasLimit:   4700000,
+			Difficulty: big.NewInt(1),
+			Alloc:      decodePrealloc(rinkebyAllocData),
+		}
+	}
+	
+	// DevGenesisBlock returns the 'geth --dev' genesis block.
+	func DevGenesisBlock() *Genesis {
+		return &Genesis{
+			Config:     params.AllProtocolChanges,
+			Nonce:      42,
+			GasLimit:   4712388,
+			Difficulty: big.NewInt(131072),
+			Alloc:      decodePrealloc(devAllocData),
+		}
+	}