package eth
import (
"container/list"
"github.com/ethereum/ethchain-go"
"github.com/ethereum/ethdb-go"
"github.com/ethereum/ethutil-go"
"github.com/ethereum/ethwire-go"
"log"
"net"
"strconv"
"sync"
"sync/atomic"
"time"
)
func eachPeer(peers *list.List, callback func(*Peer, *list.Element)) {
// Loop thru the peers and close them (if we had them)
for e := peers.Front(); e != nil; e = e.Next() {
if peer, ok := e.Value.(*Peer); ok {
callback(peer, e)
}
}
}
const (
processReapingTimeout = 60 // TODO increase
)
type Ethereum struct {
// Channel for shutting down the ethereum
shutdownChan chan bool
quit chan bool
// DB interface
//db *ethdb.LDBDatabase
db ethutil.Database
// Block manager for processing new blocks and managing the block chain
BlockManager *ethchain.BlockManager
// The transaction pool. Transaction can be pushed on this pool
// for later including in the blocks
TxPool *ethchain.TxPool
// Peers (NYI)
peers *list.List
// Nonce
Nonce uint64
Addr net.Addr
peerMut sync.Mutex
// Capabilities for outgoing peers
serverCaps Caps
nat NAT
// Specifies the desired amount of maximum peers
MaxPeers int
}
func New(caps Caps, usePnp bool) (*Ethereum, error) {
db, err := ethdb.NewLDBDatabase()
//db, err := ethdb.NewMemDatabase()
if err != nil {
return nil, err
}
var nat NAT
if usePnp {
nat, err = Discover()
if err != nil {
log.Println("UPnP failed", err)
}
}
ethutil.Config.Db = db
nonce, _ := ethutil.RandomUint64()
ethereum := &Ethereum{
shutdownChan: make(chan bool),
quit: make(chan bool),
db: db,
peers: list.New(),
Nonce: nonce,
serverCaps: caps,
nat: nat,
MaxPeers: 5,
}
ethereum.TxPool = ethchain.NewTxPool()
ethereum.TxPool.Speaker = ethereum
ethereum.BlockManager = ethchain.NewBlockManager(ethereum)
ethereum.TxPool.BlockManager = ethereum.BlockManager
ethereum.BlockManager.TransactionPool = ethereum.TxPool
return ethereum, nil
}
func (s *Ethereum) AddPeer(conn net.Conn) {
peer := NewPeer(conn, s, true)
if peer != nil && s.peers.Len() < s.MaxPeers {
s.peers.PushBack(peer)
peer.Start()
}
}
func (s *Ethereum) ProcessPeerList(addrs []string) {
for _, addr := range addrs {
// TODO Probably requires some sanity checks
s.ConnectToPeer(addr)
}
}
func (s *Ethereum) ConnectToPeer(addr string) error {
var alreadyConnected bool
eachPeer(s.peers, func(p *Peer, v *list.Element) {
if p.conn == nil {
return
}
phost, _, _ := net.SplitHostPort(p.conn.RemoteAddr().String())
ahost, _, _ := net.SplitHostPort(addr)
if phost == ahost {
alreadyConnected = true
return
}
})
if alreadyConnected {
return nil
}
peer := NewOutboundPeer(addr, s, s.serverCaps)
s.peers.PushBack(peer)
return nil
}
func (s *Ethereum) OutboundPeers() []*Peer {
// Create a new peer slice with at least the length of the total peers
outboundPeers := make([]*Peer, s.peers.Len())
length := 0
eachPeer(s.peers, func(p *Peer, e *list.Element) {
if !p.inbound && p.conn != nil {
outboundPeers[length] = p
length++
}
})
return outboundPeers[:length]
}
func (s *Ethereum) InboundPeers() []*Peer {
// Create a new peer slice with at least the length of the total peers
inboundPeers := make([]*Peer, s.peers.Len())
length := 0
eachPeer(s.peers, func(p *Peer, e *list.Element) {
if p.inbound {
inboundPeers[length] = p
length++
}
})
return inboundPeers[:length]
}
func (s *Ethereum) InOutPeers() []*Peer {
// Reap the dead peers first
s.reapPeers()
// Create a new peer slice with at least the length of the total peers
inboundPeers := make([]*Peer, s.peers.Len())
length := 0
eachPeer(s.peers, func(p *Peer, e *list.Element) {
// Only return peers with an actual ip
if len(p.host) > 0 {
inboundPeers[length] = p
length++
}
})
return inboundPeers[:length]
}
func (s *Ethereum) Broadcast(msgType ethwire.MsgType, data []interface{}) {
msg := ethwire.NewMessage(msgType, data)
s.BroadcastMsg(msg)
}
func (s *Ethereum) BroadcastMsg(msg *ethwire.Msg) {
eachPeer(s.peers, func(p *Peer, e *list.Element) {
p.QueueMessage(msg)
})
}
func (s *Ethereum) Peers() *list.List {
return s.peers
}
func (s *Ethereum) reapPeers() {
s.peerMut.Lock()
defer s.peerMut.Unlock()
eachPeer(s.peers, func(p *Peer, e *list.Element) {
if atomic.LoadInt32(&p.disconnect) == 1 || (p.inbound && (time.Now().Unix()-p.lastPong) > int64(5*time.Minute)) {
s.peers.Remove(e)
}
})
}
func (s *Ethereum) ReapDeadPeerHandler() {
reapTimer := time.NewTicker(processReapingTimeout * time.Second)
for {
select {
case <-reapTimer.C:
s.reapPeers()
}
}
}
// Start the ethereum
func (s *Ethereum) Start() {
// Bind to addr and port
ln, err := net.Listen("tcp", ":30303")
if err != nil {
log.Println("Connection listening disabled. Acting as client")
} else {
// Starting accepting connections
log.Println("Ready and accepting connections")
// Start the peer handler
go s.peerHandler(ln)
}
if s.nat != nil {
go s.upnpUpdateThread()
}
// Start the reaping processes
go s.ReapDeadPeerHandler()
// Start the tx pool
s.TxPool.Start()
}
func (s *Ethereum) peerHandler(listener net.Listener) {
for {
conn, err := listener.Accept()
if err != nil {
log.Println(err)
continue
}
go s.AddPeer(conn)
}
}
func (s *Ethereum) Stop() {
// Close the database
defer s.db.Close()
eachPeer(s.peers, func(p *Peer, e *list.Element) {
p.Stop()
})
close(s.quit)
s.TxPool.Stop()
s.BlockManager.Stop()
s.shutdownChan <- true
}
// This function will wait for a shutdown and resumes main thread execution
func (s *Ethereum) WaitForShutdown() {
<-s.shutdownChan
}
func (s *Ethereum) upnpUpdateThread() {
// Go off immediately to prevent code duplication, thereafter we renew
// lease every 15 minutes.
timer := time.NewTimer(0 * time.Second)
lport, _ := strconv.ParseInt("30303", 10, 16)
first := true
out:
for {
select {
case <-timer.C:
var err error
_, err = s.nat.AddPortMapping("TCP", int(lport), int(lport), "eth listen port", 20*60)
if err != nil {
log.Println("can't add UPnP port mapping:", err)
break out
}
if first && err == nil {
_, err = s.nat.GetExternalAddress()
if err != nil {
log.Println("UPnP can't get external address:", err)
continue out
}
first = false
}
timer.Reset(time.Minute * 15)
case <-s.quit:
break out
}
}
timer.Stop()
if err := s.nat.DeletePortMapping("TCP", int(lport), int(lport)); err != nil {
log.Println("unable to remove UPnP port mapping:", err)
} else {
log.Println("succesfully disestablished UPnP port mapping")
}
}
