go-ethereum/block_pool.go
obscuren f8d0cd9906 Added a callback mechanism to chain adding.
Not sure if this is the right approach. Why? BlockChain shouldn't need
the "Ethereum" object. BlockChain shouldn't need to worry about
notifying listeners or message propagation.
2014-11-18 19:44:17 +01:00

348 lines
8.1 KiB
Go

package eth
import (
"bytes"
"container/list"
"fmt"
"math"
"math/big"
"sync"
"time"
"github.com/ethereum/go-ethereum/chain"
"github.com/ethereum/go-ethereum/chain/types"
"github.com/ethereum/go-ethereum/ethutil"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/state"
"github.com/ethereum/go-ethereum/wire"
)
var poollogger = logger.NewLogger("BPOOL")
type block struct {
from *Peer
peer *Peer
block *types.Block
reqAt time.Time
requested int
}
type BlockPool struct {
mut sync.Mutex
eth *Ethereum
hashes [][]byte
pool map[string]*block
td *big.Int
quit chan bool
fetchingHashes bool
downloadStartedAt time.Time
ChainLength, BlocksProcessed int
peer *Peer
}
func NewBlockPool(eth *Ethereum) *BlockPool {
return &BlockPool{
eth: eth,
pool: make(map[string]*block),
td: ethutil.Big0,
quit: make(chan bool),
}
}
func (self *BlockPool) Len() int {
return len(self.hashes)
}
func (self *BlockPool) Reset() {
self.pool = make(map[string]*block)
self.hashes = nil
}
func (self *BlockPool) HasLatestHash() bool {
self.mut.Lock()
defer self.mut.Unlock()
return self.pool[string(self.eth.ChainManager().CurrentBlock.Hash())] != nil
}
func (self *BlockPool) HasCommonHash(hash []byte) bool {
return self.eth.ChainManager().GetBlock(hash) != nil
}
func (self *BlockPool) Blocks() (blocks types.Blocks) {
for _, item := range self.pool {
if item.block != nil {
blocks = append(blocks, item.block)
}
}
return
}
func (self *BlockPool) FetchHashes(peer *Peer) bool {
highestTd := self.eth.HighestTDPeer()
if (self.peer == nil && peer.td.Cmp(highestTd) >= 0) || (self.peer != nil && peer.td.Cmp(self.peer.td) > 0) || self.peer == peer {
if self.peer != peer {
poollogger.Debugf("Found better suitable peer (%v vs %v)\n", self.td, peer.td)
if self.peer != nil {
self.peer.doneFetchingHashes = true
}
}
self.peer = peer
self.td = peer.td
if !self.HasLatestHash() {
peer.doneFetchingHashes = false
const amount = 256
peerlogger.Debugf("Fetching hashes (%d) %x...\n", amount, peer.lastReceivedHash[0:4])
peer.QueueMessage(wire.NewMessage(wire.MsgGetBlockHashesTy, []interface{}{peer.lastReceivedHash, uint32(amount)}))
}
return true
}
return false
}
func (self *BlockPool) AddHash(hash []byte, peer *Peer) {
self.mut.Lock()
defer self.mut.Unlock()
if self.pool[string(hash)] == nil {
self.pool[string(hash)] = &block{peer, nil, nil, time.Now(), 0}
self.hashes = append([][]byte{hash}, self.hashes...)
}
}
func (self *BlockPool) Add(b *types.Block, peer *Peer) {
self.addBlock(b, peer, false)
}
func (self *BlockPool) AddNew(b *types.Block, peer *Peer) {
self.addBlock(b, peer, true)
}
func (self *BlockPool) addBlock(b *types.Block, peer *Peer, newBlock bool) {
self.mut.Lock()
defer self.mut.Unlock()
hash := string(b.Hash())
if self.pool[hash] == nil && !self.eth.ChainManager().HasBlock(b.Hash()) {
poollogger.Infof("Got unrequested block (%x...)\n", hash[0:4])
self.hashes = append(self.hashes, b.Hash())
self.pool[hash] = &block{peer, peer, b, time.Now(), 0}
// The following is only performed on an unrequested new block
if newBlock {
fmt.Println("1.", !self.eth.ChainManager().HasBlock(b.PrevHash), ethutil.Bytes2Hex(b.Hash()[0:4]), ethutil.Bytes2Hex(b.PrevHash[0:4]))
fmt.Println("2.", self.pool[string(b.PrevHash)] == nil)
fmt.Println("3.", !self.fetchingHashes)
if !self.eth.ChainManager().HasBlock(b.PrevHash) && self.pool[string(b.PrevHash)] == nil && !self.fetchingHashes {
poollogger.Infof("Unknown chain, requesting (%x...)\n", b.PrevHash[0:4])
peer.QueueMessage(wire.NewMessage(wire.MsgGetBlockHashesTy, []interface{}{b.Hash(), uint32(256)}))
}
}
} else if self.pool[hash] != nil {
self.pool[hash].block = b
}
self.BlocksProcessed++
}
func (self *BlockPool) Remove(hash []byte) {
self.mut.Lock()
defer self.mut.Unlock()
self.hashes = ethutil.DeleteFromByteSlice(self.hashes, hash)
delete(self.pool, string(hash))
}
func (self *BlockPool) DistributeHashes() {
self.mut.Lock()
defer self.mut.Unlock()
var (
peerLen = self.eth.peers.Len()
amount = 256 * peerLen
dist = make(map[*Peer][][]byte)
)
num := int(math.Min(float64(amount), float64(len(self.pool))))
for i, j := 0, 0; i < len(self.hashes) && j < num; i++ {
hash := self.hashes[i]
item := self.pool[string(hash)]
if item != nil && item.block == nil {
var peer *Peer
lastFetchFailed := time.Since(item.reqAt) > 5*time.Second
// Handle failed requests
if lastFetchFailed && item.requested > 5 && item.peer != nil {
if item.requested < 100 {
// Select peer the hash was retrieved off
peer = item.from
} else {
// Remove it
self.hashes = ethutil.DeleteFromByteSlice(self.hashes, hash)
delete(self.pool, string(hash))
}
} else if lastFetchFailed || item.peer == nil {
// Find a suitable, available peer
eachPeer(self.eth.peers, func(p *Peer, v *list.Element) {
if peer == nil && len(dist[p]) < amount/peerLen && p.statusKnown {
peer = p
}
})
}
if peer != nil {
item.reqAt = time.Now()
item.peer = peer
item.requested++
dist[peer] = append(dist[peer], hash)
}
}
}
for peer, hashes := range dist {
peer.FetchBlocks(hashes)
}
if len(dist) > 0 {
self.downloadStartedAt = time.Now()
}
}
func (self *BlockPool) Start() {
go self.downloadThread()
go self.chainThread()
}
func (self *BlockPool) Stop() {
close(self.quit)
}
func (self *BlockPool) downloadThread() {
serviceTimer := time.NewTicker(100 * time.Millisecond)
out:
for {
select {
case <-self.quit:
break out
case <-serviceTimer.C:
// Check if we're catching up. If not distribute the hashes to
// the peers and download the blockchain
self.fetchingHashes = false
eachPeer(self.eth.peers, func(p *Peer, v *list.Element) {
if p.statusKnown && p.FetchingHashes() {
self.fetchingHashes = true
}
})
if len(self.hashes) > 0 {
self.DistributeHashes()
}
if self.ChainLength < len(self.hashes) {
self.ChainLength = len(self.hashes)
}
/*
if !self.fetchingHashes {
blocks := self.Blocks()
chain.BlockBy(chain.Number).Sort(blocks)
if len(blocks) > 0 {
if !self.eth.ChainManager().HasBlock(b.PrevHash) && self.pool[string(b.PrevHash)] == nil && !self.fetchingHashes {
}
}
}
*/
}
}
}
func (self *BlockPool) chainThread() {
procTimer := time.NewTicker(500 * time.Millisecond)
out:
for {
select {
case <-self.quit:
break out
case <-procTimer.C:
blocks := self.Blocks()
types.BlockBy(types.Number).Sort(blocks)
// Find common block
for i, block := range blocks {
if self.eth.ChainManager().HasBlock(block.PrevHash) {
blocks = blocks[i:]
break
}
}
if len(blocks) > 0 {
if self.eth.ChainManager().HasBlock(blocks[0].PrevHash) {
for i, block := range blocks[1:] {
// NOTE: The Ith element in this loop refers to the previous block in
// outer "blocks"
if bytes.Compare(block.PrevHash, blocks[i].Hash()) != 0 {
blocks = blocks[:i]
break
}
}
} else {
blocks = nil
}
}
if len(blocks) > 0 {
chainManager := self.eth.ChainManager()
// Test and import
bchain := chain.NewChain(blocks)
_, err := chainManager.TestChain(bchain)
if err != nil && !chain.IsTDError(err) {
poollogger.Debugln(err)
self.Reset()
if self.peer != nil && self.peer.conn != nil {
poollogger.Debugf("Punishing peer for supplying bad chain (%v)\n", self.peer.conn.RemoteAddr())
}
// This peer gave us bad hashes and made us fetch a bad chain, therefor he shall be punished.
self.eth.BlacklistPeer(self.peer)
self.peer.StopWithReason(DiscBadPeer)
self.td = ethutil.Big0
self.peer = nil
} else {
if !chain.IsTDError(err) {
chainManager.InsertChain(bchain, func(block *types.Block, messages state.Messages) {
self.eth.EventMux().Post(chain.NewBlockEvent{block})
self.eth.EventMux().Post(messages)
self.Remove(block.Hash())
})
}
}
}
}
}
}