github.com/linapex/ethereum-go-chinese@v0.0.0-20190316121929-f8b7a73c3fa1/les/txrelay.go (about)

     1  
     2  //<developer>
     3  //    <name>linapex 曹一峰</name>
     4  //    <email>linapex@163.com</email>
     5  //    <wx>superexc</wx>
     6  //    <qqgroup>128148617</qqgroup>
     7  //    <url>https://jsq.ink</url>
     8  //    <role>pku engineer</role>
     9  //    <date>2019-03-16 19:16:39</date>
    10  //</624450096301346816>
    11  
    12  
    13  package les
    14  
    15  import (
    16  	"sync"
    17  
    18  	"github.com/ethereum/go-ethereum/common"
    19  	"github.com/ethereum/go-ethereum/core/types"
    20  )
    21  
    22  type ltrInfo struct {
    23  	tx     *types.Transaction
    24  	sentTo map[*peer]struct{}
    25  }
    26  
    27  type LesTxRelay struct {
    28  	txSent       map[common.Hash]*ltrInfo
    29  	txPending    map[common.Hash]struct{}
    30  	ps           *peerSet
    31  	peerList     []*peer
    32  	peerStartPos int
    33  	lock         sync.RWMutex
    34  
    35  	reqDist *requestDistributor
    36  }
    37  
    38  func NewLesTxRelay(ps *peerSet, reqDist *requestDistributor) *LesTxRelay {
    39  	r := &LesTxRelay{
    40  		txSent:    make(map[common.Hash]*ltrInfo),
    41  		txPending: make(map[common.Hash]struct{}),
    42  		ps:        ps,
    43  		reqDist:   reqDist,
    44  	}
    45  	ps.notify(r)
    46  	return r
    47  }
    48  
    49  func (self *LesTxRelay) registerPeer(p *peer) {
    50  	self.lock.Lock()
    51  	defer self.lock.Unlock()
    52  
    53  	self.peerList = self.ps.AllPeers()
    54  }
    55  
    56  func (self *LesTxRelay) unregisterPeer(p *peer) {
    57  	self.lock.Lock()
    58  	defer self.lock.Unlock()
    59  
    60  	self.peerList = self.ps.AllPeers()
    61  }
    62  
    63  //send最多向给定数量的对等方发送一个事务列表
    64  //一次，不要将任何特定事务重新发送到同一个对等机两次
    65  func (self *LesTxRelay) send(txs types.Transactions, count int) {
    66  	sendTo := make(map[*peer]types.Transactions)
    67  
    68  self.peerStartPos++ //旋转对等列表的起始位置
    69  	if self.peerStartPos >= len(self.peerList) {
    70  		self.peerStartPos = 0
    71  	}
    72  
    73  	for _, tx := range txs {
    74  		hash := tx.Hash()
    75  		ltr, ok := self.txSent[hash]
    76  		if !ok {
    77  			ltr = &ltrInfo{
    78  				tx:     tx,
    79  				sentTo: make(map[*peer]struct{}),
    80  			}
    81  			self.txSent[hash] = ltr
    82  			self.txPending[hash] = struct{}{}
    83  		}
    84  
    85  		if len(self.peerList) > 0 {
    86  			cnt := count
    87  			pos := self.peerStartPos
    88  			for {
    89  				peer := self.peerList[pos]
    90  				if _, ok := ltr.sentTo[peer]; !ok {
    91  					sendTo[peer] = append(sendTo[peer], tx)
    92  					ltr.sentTo[peer] = struct{}{}
    93  					cnt--
    94  				}
    95  				if cnt == 0 {
    96  break //发送到所需的对等数
    97  				}
    98  				pos++
    99  				if pos == len(self.peerList) {
   100  					pos = 0
   101  				}
   102  				if pos == self.peerStartPos {
   103  break //已尝试所有可用的对等机
   104  				}
   105  			}
   106  		}
   107  	}
   108  
   109  	for p, list := range sendTo {
   110  		pp := p
   111  		ll := list
   112  
   113  		reqID := genReqID()
   114  		rq := &distReq{
   115  			getCost: func(dp distPeer) uint64 {
   116  				peer := dp.(*peer)
   117  				return peer.GetRequestCost(SendTxMsg, len(ll))
   118  			},
   119  			canSend: func(dp distPeer) bool {
   120  				return dp.(*peer) == pp
   121  			},
   122  			request: func(dp distPeer) func() {
   123  				peer := dp.(*peer)
   124  				cost := peer.GetRequestCost(SendTxMsg, len(ll))
   125  				peer.fcServer.QueueRequest(reqID, cost)
   126  				return func() { peer.SendTxs(reqID, cost, ll) }
   127  			},
   128  		}
   129  		self.reqDist.queue(rq)
   130  	}
   131  }
   132  
   133  func (self *LesTxRelay) Send(txs types.Transactions) {
   134  	self.lock.Lock()
   135  	defer self.lock.Unlock()
   136  
   137  	self.send(txs, 3)
   138  }
   139  
   140  func (self *LesTxRelay) NewHead(head common.Hash, mined []common.Hash, rollback []common.Hash) {
   141  	self.lock.Lock()
   142  	defer self.lock.Unlock()
   143  
   144  	for _, hash := range mined {
   145  		delete(self.txPending, hash)
   146  	}
   147  
   148  	for _, hash := range rollback {
   149  		self.txPending[hash] = struct{}{}
   150  	}
   151  
   152  	if len(self.txPending) > 0 {
   153  		txs := make(types.Transactions, len(self.txPending))
   154  		i := 0
   155  		for hash := range self.txPending {
   156  			txs[i] = self.txSent[hash].tx
   157  			i++
   158  		}
   159  		self.send(txs, 1)
   160  	}
   161  }
   162  
   163  func (self *LesTxRelay) Discard(hashes []common.Hash) {
   164  	self.lock.Lock()
   165  	defer self.lock.Unlock()
   166  
   167  	for _, hash := range hashes {
   168  		delete(self.txSent, hash)
   169  		delete(self.txPending, hash)
   170  	}
   171  }
   172