path: root/miner/miner.go

package miner

import (
    "bytes"
    "sort"

    "github.com/ethereum/go-ethereum/chain"
    "github.com/ethereum/go-ethereum/event"
    "github.com/ethereum/go-ethereum/logger"
    "github.com/ethereum/go-ethereum/wire"
)

var minerlogger = logger.NewLogger("MINER")

type Miner struct {
    pow      chain.PoW
    ethereum chain.EthManager
    coinbase []byte
    txs      chain.Transactions
    uncles   []*chain.Block
    block    *chain.Block

    events      event.Subscription
    powQuitChan chan struct{}
    powDone     chan struct{}

    turbo bool
}

const (
    Started = iota
    Stopped
)

type Event struct {
    Type  int // Started || Stopped
    Miner *Miner
}

func (self *Miner) GetPow() chain.PoW {
    return self.pow
}

func NewDefaultMiner(coinbase []byte, ethereum chain.EthManager) *Miner {
    miner := Miner{
        pow:      &chain.EasyPow{},
        ethereum: ethereum,
        coinbase: coinbase,
    }

    return &miner
}

func (self *Miner) ToggleTurbo() {
    self.turbo = !self.turbo

    self.pow.Turbo(self.turbo)
}

func (miner *Miner) Start() {

    // Insert initial TXs in our little miner 'pool'
    miner.txs = miner.ethereum.TxPool().Flush()
    miner.block = miner.ethereum.ChainManager().NewBlock(miner.coinbase)

    mux := miner.ethereum.EventMux()
    miner.events = mux.Subscribe(chain.NewBlockEvent{}, chain.TxPreEvent{})

    // Prepare inital block
    //miner.ethereum.StateManager().Prepare(miner.block.State(), miner.block.State())
    go miner.listener()

    minerlogger.Infoln("Started")
    mux.Post(Event{Started, miner})
}

func (miner *Miner) Stop() {
    minerlogger.Infoln("Stopping...")
    miner.events.Unsubscribe()
    miner.ethereum.EventMux().Post(Event{Stopped, miner})
}

func (miner *Miner) listener() {
    miner.startMining()

    for {
        select {
        case event := <-miner.events.Chan():
            switch event := event.(type) {
            case chain.NewBlockEvent:
                miner.stopMining()

                block := event.Block
                //minerlogger.Infoln("Got new block via Reactor")
                if bytes.Compare(miner.ethereum.ChainManager().CurrentBlock.Hash(), block.Hash()) == 0 {
                    // TODO: Perhaps continue mining to get some uncle rewards
                    //minerlogger.Infoln("New top block found resetting state")

                    // Filter out which Transactions we have that were not in this block
                    var newtxs []*chain.Transaction
                    for _, tx := range miner.txs {
                        found := false
                        for _, othertx := range block.Transactions() {
                            if bytes.Compare(tx.Hash(), othertx.Hash()) == 0 {
                                found = true
                            }
                        }
                        if found == false {
                            newtxs = append(newtxs, tx)
                        }
                    }
                    miner.txs = newtxs
                } else {
                    if bytes.Compare(block.PrevHash, miner.ethereum.ChainManager().CurrentBlock.PrevHash) == 0 {
                        minerlogger.Infoln("Adding uncle block")
                        miner.uncles = append(miner.uncles, block)
                    }
                }
                miner.startMining()

            case chain.TxPreEvent:
                miner.stopMining()

                found := false
                for _, ctx := range miner.txs {
                    if found = bytes.Compare(ctx.Hash(), event.Tx.Hash()) == 0; found {
                        break
                    }

                    miner.startMining()
                }
                if found == false {
                    // Undo all previous commits
                    miner.block.Undo()
                    // Apply new transactions
                    miner.txs = append(miner.txs, event.Tx)
                }
            }

        case <-miner.powDone:
            miner.startMining()
        }
    }
}

func (miner *Miner) startMining() {
    if miner.powDone == nil {
        miner.powDone = make(chan struct{})
    }
    miner.powQuitChan = make(chan struct{})
    go miner.mineNewBlock()
}

func (miner *Miner) stopMining() {
    println("stop mining")
    _, isopen := <-miner.powQuitChan
    if isopen {
        close(miner.powQuitChan)
    }
    //<-miner.powDone
}

func (self *Miner) mineNewBlock() {
    stateManager := self.ethereum.StateManager()

    self.block = self.ethereum.ChainManager().NewBlock(self.coinbase)

    // Apply uncles
    if len(self.uncles) > 0 {
        self.block.SetUncles(self.uncles)
    }

    // Sort the transactions by nonce in case of odd network propagation
    sort.Sort(chain.TxByNonce{self.txs})

    // Accumulate all valid transactions and apply them to the new state
    // Error may be ignored. It's not important during mining
    parent := self.ethereum.ChainManager().GetBlock(self.block.PrevHash)
    coinbase := self.block.State().GetOrNewStateObject(self.block.Coinbase)
    coinbase.SetGasPool(self.block.CalcGasLimit(parent))
    receipts, txs, unhandledTxs, erroneous, err := stateManager.ProcessTransactions(coinbase, self.block.State(), self.block, self.block, self.txs)
    if err != nil {
        minerlogger.Debugln(err)
    }
    self.ethereum.TxPool().RemoveSet(erroneous)
    self.txs = append(txs, unhandledTxs...)

    self.block.SetTransactions(txs)
    self.block.SetReceipts(receipts)

    // Accumulate the rewards included for this block
    stateManager.AccumelateRewards(self.block.State(), self.block, parent)

    self.block.State().Update()

    minerlogger.Infof("Mining on block. Includes %v transactions", len(self.txs))

    // Find a valid nonce
    nonce := self.pow.Search(self.block, self.powQuitChan)
    if nonce != nil {
        self.block.Nonce = nonce
        err := self.ethereum.StateManager().Process(self.block)
        if err != nil {
            minerlogger.Infoln(err)
        } else {
            self.ethereum.Broadcast(wire.MsgBlockTy, []interface{}{self.block.Value().Val})
            minerlogger.Infof("🔨  Mined block %x\n", self.block.Hash())
            minerlogger.Infoln(self.block)
            // Gather the new batch of transactions currently in the tx pool
            self.txs = self.ethereum.TxPool().CurrentTransactions()
            self.ethereum.EventMux().Post(chain.NewBlockEvent{self.block})
        }

        // Continue mining on the next block
        self.startMining()
    }
}