make some comment with discv5 modification

Signed-off-by: Chen Kai <281165273grape@gmail.com>

p2p/discover/table.go

@@ -174,24 +174,6 @@ func (tab *Table) Nodes() [][]BucketNode {
 	return nodes
 }
 
-// NodeList returns all nodes contained in the table.
-func (tab *Table) NodeList() []*enode.Node {
-	if !tab.isInitDone() {
-		return nil
-	}
-
-	tab.mutex.Lock()
-	defer tab.mutex.Unlock()
-
-	var nodes []*enode.Node
-	for _, b := range &tab.buckets {
-		for _, n := range b.entries {
-			nodes = append(nodes, n.Node)
-		}
-	}
-	return nodes
-}
-
 func (tab *Table) self() *enode.Node {
 	return tab.net.Self()
 }
@@ -525,13 +507,11 @@ func (tab *Table) removeIP(b *bucket, ip netip.Addr) {
 // The caller must hold tab.mutex.
 func (tab *Table) handleAddNode(req addNodeOp) bool {
 	if req.node.ID() == tab.self().ID() {
-		tab.log.Debug("this node is already in table", "id", req.node.ID())
 		return false
 	}
 	// For nodes from inbound contact, there is an additional safety measure: if the table
 	// is still initializing the node is not added.
 	if req.isInbound && !tab.isInitDone() {
-		tab.log.Debug("table is not ready")
 		return false
 	}
 
@@ -539,18 +519,15 @@ func (tab *Table) handleAddNode(req addNodeOp) bool {
 	n, _ := tab.bumpInBucket(b, req.node, req.isInbound)
 	if n != nil {
 		// Already in bucket.
-		tab.log.Debug("the node is already in table", "id", req.node.ID())
 		return false
 	}
 	if len(b.entries) >= BucketSize {
 		// Bucket full, maybe add as replacement.
-		tab.log.Debug("the bucket is full and will add in replacement", "id", req.node.ID())
 		tab.addReplacement(b, req.node)
 		return false
 	}
 	if !tab.addIP(b, req.node.IPAddr()) {
 		// Can't add: IP limit reached.
-		tab.log.Debug("IP limit reached", "id", req.node.ID())
 		return false
 	}
 
@@ -718,10 +695,12 @@ func pushNode(list []*tableNode, n *tableNode, max int) ([]*tableNode, *tableNod
 	return list, removed
 }
 
+// WaitInit waits until the table is initialized.
 func (tab *Table) WaitInit() {
 	<-tab.initDone
 }
 
+// NodeIds returns the node IDs in the table.
 func (tab *Table) NodeIds() [][]string {
 	tab.mutex.Lock()
 	defer tab.mutex.Unlock()
@@ -736,13 +715,33 @@ func (tab *Table) NodeIds() [][]string {
 	return nodes
 }
 
+// Config returns the table's configuration.
 func (tab *Table) Config() Config {
 	return tab.cfg
 }
 
+// DeleteNode removes a node from the table.
 func (tab *Table) DeleteNode(n *enode.Node) {
 	tab.mutex.Lock()
 	defer tab.mutex.Unlock()
 	b := tab.bucket(n.ID())
 	tab.deleteInBucket(b, n.ID())
 }
+
+// NodeList returns all nodes contained in the table.
+func (tab *Table) NodeList() []*enode.Node {
+	if !tab.isInitDone() {
+		return nil
+	}
+
+	tab.mutex.Lock()
+	defer tab.mutex.Unlock()
+
+	var nodes []*enode.Node
+	for _, b := range &tab.buckets {
+		for _, n := range b.entries {
+			nodes = append(nodes, n.Node)
+		}
+	}
+	return nodes
+}

p2p/discover/v5_udp.go

@@ -43,6 +43,7 @@ const (
 	findnodeResultLimit     = 16 // applies in FINDNODE handler
 	totalNodesResponseLimit = 5  // applies in waitForNodes
 
+	// change to a configurable value
 	respTimeoutV5 = 3 * time.Second
 )
 
@@ -62,9 +63,10 @@ type codecV5 interface {
 // UDPv5 is the implementation of protocol version 5.
 type UDPv5 struct {
 	// static fields
-	conn           UDPConn
-	tab            *Table
-	nodeMu         sync.Mutex
+	conn   UDPConn
+	tab    *Table
+	nodeMu sync.Mutex
+	// addr -> node cache which cached the nodes we have sent packets to or received packets from recently.
 	cachedAddrNode map[string]*enode.Node
 	netrestrict    *netutil.Netlist
 	priv           *ecdsa.PrivateKey
@@ -262,30 +264,11 @@ func (t *UDPv5) ResolveNodeId(id enode.ID) *enode.Node {
 
 // AllNodes returns all the nodes stored in the local table.
 func (t *UDPv5) AllNodes() []*enode.Node {
-	t.tab.mutex.Lock()
-	defer t.tab.mutex.Unlock()
-	nodes := make([]*enode.Node, 0)
-
-	for _, b := range &t.tab.buckets {
-		for _, n := range b.entries {
-			nodes = append(nodes, n.Node)
-		}
-	}
-	return nodes
+	return t.tab.NodeList()
 }
 
 func (t *UDPv5) RoutingTableInfo() [][]string {
-	t.tab.mutex.Lock()
-	defer t.tab.mutex.Unlock()
-	nodes := make([][]string, 0)
-	for _, b := range &t.tab.buckets {
-		bucketNodes := make([]string, 0)
-		for _, n := range b.entries {
-			bucketNodes = append(bucketNodes, "0x"+n.ID().String())
-		}
-		nodes = append(nodes, bucketNodes)
-	}
-	return nodes
+	return t.tab.NodeIds()
 }
 
 // LocalNode returns the current local Node running the
@@ -602,6 +585,7 @@ func (t *UDPv5) dispatch() {
 			t.sendNextCall(c.id)
 
 		case r := <-t.sendCh:
+			// make send request by another thread also be cached to handle WHOAREYOU
 			c := &callV5{id: r.destID, addr: r.destAddr}
 			c.node = r.destNode
 			c.packet = r.msg
@@ -619,7 +603,6 @@ func (t *UDPv5) dispatch() {
 			c.nonce = nonce
 			t.activeCallByAuth[nonce] = c
 			t.startResponseTimeout(c)
-			//t.send(r.destID, r.destAddr, r.msg, nil)
 
 		case p := <-t.packetInCh:
 			t.handlePacket(p.Data, p.Addr)