Golang Block.GasLimit方法代碼示例

// Process processes the state changes according to the Ethereum rules by running
// the transaction messages using the statedb and applying any rewards to both
// the processor (coinbase) and any included uncles.
//
// Process returns the receipts and logs accumulated during the process and
// returns the amount of gas that was used in the process. If any of the
// transactions failed to execute due to insufficient gas it will return an error.
func (p *StateProcessor) Process(block *types.Block, statedb *state.StateDB, cfg vm.Config) (types.Receipts, vm.Logs, *big.Int, error) {
	var (
		receipts     types.Receipts
		totalUsedGas = big.NewInt(0)
		err          error
		header       = block.Header()
		allLogs      vm.Logs
		gp           = new(GasPool).AddGas(block.GasLimit())
	)
	// Mutate the the block and state according to any hard-fork specs
	if p.config.DAOForkSupport && p.config.DAOForkBlock != nil && p.config.DAOForkBlock.Cmp(block.Number()) == 0 {
		ApplyDAOHardFork(statedb)
	}
	// Iterate over and process the individual transactions
	for i, tx := range block.Transactions() {
		statedb.StartRecord(tx.Hash(), block.Hash(), i)
		receipt, logs, _, err := ApplyTransaction(p.config, p.bc, gp, statedb, header, tx, totalUsedGas, cfg)
		if err != nil {
			return nil, nil, totalUsedGas, err
		}
		receipts = append(receipts, receipt)
		allLogs = append(allLogs, logs...)
	}
	AccumulateRewards(statedb, header, block.Uncles())

	return receipts, allLogs, totalUsedGas, err
}

// Creates a new QML Block from a chain block
func NewBlock(block *types.Block) *Block {
	if block == nil {
		return &Block{}
	}

	ptxs := make([]*Transaction, len(block.Transactions()))
	/*
		for i, tx := range block.Transactions() {
			ptxs[i] = NewTx(tx)
		}
	*/
	txlist := common.NewList(ptxs)

	puncles := make([]*Block, len(block.Uncles()))
	/*
		for i, uncle := range block.Uncles() {
			puncles[i] = NewBlock(types.NewBlockWithHeader(uncle))
		}
	*/
	ulist := common.NewList(puncles)

	return &Block{
		ref: block, Size: block.Size().String(),
		Number: int(block.NumberU64()), GasUsed: block.GasUsed().String(),
		GasLimit: block.GasLimit().String(), Hash: block.Hash().Hex(),
		Transactions: txlist, Uncles: ulist,
		Time:     block.Time(),
		Coinbase: block.Coinbase().Hex(),
		PrevHash: block.ParentHash().Hex(),
		Bloom:    common.ToHex(block.Bloom().Bytes()),
		Raw:      block.String(),
	}
}

// returns the lowers possible price with which a tx was or could have been included
func (self *GasPriceOracle) lowestPrice(block *types.Block) *big.Int {
	gasUsed := new(big.Int)

	receipts := self.eth.BlockProcessor().GetBlockReceipts(block.Hash())
	if len(receipts) > 0 {
		if cgu := receipts[len(receipts)-1].CumulativeGasUsed; cgu != nil {
			gasUsed = receipts[len(receipts)-1].CumulativeGasUsed
		}
	}

	if new(big.Int).Mul(gasUsed, big.NewInt(100)).Cmp(new(big.Int).Mul(block.GasLimit(),
		big.NewInt(int64(self.eth.GpoFullBlockRatio)))) < 0 {
		// block is not full, could have posted a tx with MinGasPrice
		return self.eth.GpoMinGasPrice
	}

	txs := block.Transactions()
	if len(txs) == 0 {
		return self.eth.GpoMinGasPrice
	}
	// block is full, find smallest gasPrice
	minPrice := txs[0].GasPrice()
	for i := 1; i < len(txs); i++ {
		price := txs[i].GasPrice()
		if price.Cmp(minPrice) < 0 {
			minPrice = price
		}
	}
	return minPrice
}

func CalcGasLimit(parent *types.Block) *big.Int {
	// ((1024-1) * parent.gasLimit + (gasUsed * 6 / 5)) / 1024
	previous := new(big.Int).Mul(big.NewInt(1024-1), parent.GasLimit())
	current := new(big.Rat).Mul(new(big.Rat).SetInt(parent.GasUsed()), big.NewRat(6, 5))
	curInt := new(big.Int).Div(current.Num(), current.Denom())

	result := new(big.Int).Add(previous, curInt)
	result.Div(result, big.NewInt(1024))
	return common.BigMax(params.GenesisGasLimit, result)
}

func (sm *BlockProcessor) TransitionState(statedb *state.StateDB, parent, block *types.Block, transientProcess bool) (receipts types.Receipts, err error) {
	gp := statedb.GetOrNewStateObject(block.Coinbase())
	gp.SetGasLimit(block.GasLimit())

	// Process the transactions on to parent state
	receipts, err = sm.ApplyTransactions(gp, statedb, block, block.Transactions(), transientProcess)
	if err != nil {
		return nil, err
	}

	return receipts, nil
}

func (sm *BlockProcessor) TransitionState(statedb *state.StateDB, parent, block *types.Block, transientProcess bool) (receipts types.Receipts, err error) {
	gp := new(GasPool).AddGas(block.GasLimit())
	if glog.V(logger.Core) {
		glog.Infof("%x: gas (+ %v)", block.Coinbase(), gp)
	}

	// Process the transactions on to parent state
	receipts, err = sm.ApplyTransactions(gp, statedb, block, block.Transactions(), transientProcess)
	if err != nil {
		return nil, err
	}

	return receipts, nil
}

// See YP section 4.3.4. "Block Header Validity"
// Validates a block. Returns an error if the block is invalid.
func ValidateHeader(pow pow.PoW, block *types.Header, parent *types.Block, checkPow, uncle bool) error {
	if big.NewInt(int64(len(block.Extra))).Cmp(params.MaximumExtraDataSize) == 1 {
		return fmt.Errorf("Block extra data too long (%d)", len(block.Extra))
	}

	if uncle {
		if block.Time.Cmp(common.MaxBig) == 1 {
			return BlockTSTooBigErr
		}
	} else {
		if block.Time.Cmp(big.NewInt(time.Now().Unix())) == 1 {
			return BlockFutureErr
		}
	}
	if block.Time.Cmp(parent.Time()) != 1 {
		return BlockEqualTSErr
	}

	expd := CalcDifficulty(block.Time.Uint64(), parent.Time().Uint64(), parent.Number(), parent.Difficulty())
	if expd.Cmp(block.Difficulty) != 0 {
		return fmt.Errorf("Difficulty check failed for block %v, %v", block.Difficulty, expd)
	}

	var a, b *big.Int
	a = parent.GasLimit()
	a = a.Sub(a, block.GasLimit)
	a.Abs(a)
	b = parent.GasLimit()
	b = b.Div(b, params.GasLimitBoundDivisor)
	if !(a.Cmp(b) < 0) || (block.GasLimit.Cmp(params.MinGasLimit) == -1) {
		return fmt.Errorf("GasLimit check failed for block %v (%v > %v)", block.GasLimit, a, b)
	}

	num := parent.Number()
	num.Sub(block.Number, num)
	if num.Cmp(big.NewInt(1)) != 0 {
		return BlockNumberErr
	}

	if checkPow {
		// Verify the nonce of the block. Return an error if it's not valid
		if !pow.Verify(types.NewBlockWithHeader(block)) {
			return ValidationError("Block's nonce is invalid (= %x)", block.Nonce)
		}
	}

	return nil
}

func NewBlockRes(block *types.Block, td *big.Int, fullTx bool) *BlockRes {
	if block == nil {
		return nil
	}

	res := new(BlockRes)
	res.fullTx = fullTx
	res.BlockNumber = newHexNum(block.Number())
	res.BlockHash = newHexData(block.Hash())
	res.ParentHash = newHexData(block.ParentHash())
	res.Nonce = newHexData(block.Nonce())
	res.Sha3Uncles = newHexData(block.UncleHash())
	res.LogsBloom = newHexData(block.Bloom())
	res.TransactionRoot = newHexData(block.TxHash())
	res.StateRoot = newHexData(block.Root())
	res.ReceiptRoot = newHexData(block.ReceiptHash())
	res.Miner = newHexData(block.Coinbase())
	res.Difficulty = newHexNum(block.Difficulty())
	res.TotalDifficulty = newHexNum(td)
	res.Size = newHexNum(block.Size().Int64())
	res.ExtraData = newHexData(block.Extra())
	res.GasLimit = newHexNum(block.GasLimit())
	res.GasUsed = newHexNum(block.GasUsed())
	res.UnixTimestamp = newHexNum(block.Time())

	txs := block.Transactions()
	res.Transactions = make([]*TransactionRes, len(txs))
	for i, tx := range txs {
		res.Transactions[i] = NewTransactionRes(tx)
		res.Transactions[i].BlockHash = res.BlockHash
		res.Transactions[i].BlockNumber = res.BlockNumber
		res.Transactions[i].TxIndex = newHexNum(i)
	}

	uncles := block.Uncles()
	res.Uncles = make([]*UncleRes, len(uncles))
	for i, uncle := range uncles {
		res.Uncles[i] = NewUncleRes(uncle)
	}

	return res
}

// CalcGasLimit computes the gas limit of the next block after parent.
// The result may be modified by the caller.
// This is miner strategy, not consensus protocol.
func CalcGasLimit(parent *types.Block) *big.Int {
	// contrib = (parentGasUsed * 3 / 2) / 1024
	contrib := new(big.Int).Mul(parent.GasUsed(), big.NewInt(3))
	contrib = contrib.Div(contrib, big.NewInt(2))
	contrib = contrib.Div(contrib, params.GasLimitBoundDivisor)

	// decay = parentGasLimit / 1024 -1
	decay := new(big.Int).Div(parent.GasLimit(), params.GasLimitBoundDivisor)
	decay.Sub(decay, big.NewInt(1))

	/*
		strategy: gasLimit of block-to-mine is set based on parent's
		gasUsed value.  if parentGasUsed > parentGasLimit * (2/3) then we
		increase it, otherwise lower it (or leave it unchanged if it's right
		at that usage) the amount increased/decreased depends on how far away
		from parentGasLimit * (2/3) parentGasUsed is.
	*/
	gl := new(big.Int).Sub(parent.GasLimit(), decay)
	gl = gl.Add(gl, contrib)
	gl.Set(common.BigMax(gl, params.MinGasLimit))

	// however, if we're now below the target (TargetGasLimit) we increase the
	// limit as much as we can (parentGasLimit / 1024 -1)
	if gl.Cmp(params.TargetGasLimit) < 0 {
		gl.Add(parent.GasLimit(), decay)
		gl.Set(common.BigMin(gl, params.TargetGasLimit))
	}
	return gl
}

// Process processes the state changes according to the Ethereum rules by running
// the transaction messages using the statedb and applying any rewards to both
// the processor (coinbase) and any included uncles.
//
// Process returns the receipts and logs accumulated during the process and
// returns the amount of gas that was used in the process. If any of the
// transactions failed to execute due to insufficient gas it will return an error.
func (p *StateProcessor) Process(block *types.Block, statedb *state.StateDB, cfg vm.Config) (types.Receipts, vm.Logs, *big.Int, error) {
	var (
		receipts     types.Receipts
		totalUsedGas = big.NewInt(0)
		err          error
		header       = block.Header()
		allLogs      vm.Logs
		gp           = new(GasPool).AddGas(block.GasLimit())
	)

	for i, tx := range block.Transactions() {
		statedb.StartRecord(tx.Hash(), block.Hash(), i)
		receipt, logs, _, err := ApplyTransaction(p.config, p.bc, gp, statedb, header, tx, totalUsedGas, cfg)
		if err != nil {
			return nil, nil, totalUsedGas, err
		}
		receipts = append(receipts, receipt)
		allLogs = append(allLogs, logs...)
	}
	AccumulateRewards(statedb, header, block.Uncles())

	return receipts, allLogs, totalUsedGas, err
}

// CalcGasLimit computes the gas limit of the next block after parent.
// The result may be modified by the caller.
func CalcGasLimit(parent *types.Block) *big.Int {
	decay := new(big.Int).Div(parent.GasLimit(), params.GasLimitBoundDivisor)
	contrib := new(big.Int).Mul(parent.GasUsed(), big.NewInt(3))
	contrib = contrib.Div(contrib, big.NewInt(2))
	contrib = contrib.Div(contrib, params.GasLimitBoundDivisor)

	gl := new(big.Int).Sub(parent.GasLimit(), decay)
	gl = gl.Add(gl, contrib)
	gl = gl.Add(gl, big.NewInt(1))
	gl.Set(common.BigMax(gl, params.MinGasLimit))

	if gl.Cmp(params.GenesisGasLimit) < 0 {
		gl.Add(parent.GasLimit(), decay)
		gl.Set(common.BigMin(gl, params.GenesisGasLimit))
	}
	return gl
}