update vendors

vendor/github.com/fatedier/kcp-go/readloop_linux.go

@@ -0,0 +1,120 @@
+// +build linux
+
+package kcp
+
+import (
+	"net"
+	"os"
+	"sync/atomic"
+
+	"github.com/pkg/errors"
+	"golang.org/x/net/ipv4"
+	"golang.org/x/net/ipv6"
+)
+
+// the read loop for a client session
+func (s *UDPSession) readLoop() {
+	// default version
+	if s.xconn == nil {
+		s.defaultReadLoop()
+		return
+	}
+
+	// x/net version
+	var src string
+	msgs := make([]ipv4.Message, batchSize)
+	for k := range msgs {
+		msgs[k].Buffers = [][]byte{make([]byte, mtuLimit)}
+	}
+
+	for {
+		if count, err := s.xconn.ReadBatch(msgs, 0); err == nil {
+			for i := 0; i < count; i++ {
+				msg := &msgs[i]
+				// make sure the packet is from the same source
+				if src == "" { // set source address if nil
+					src = msg.Addr.String()
+				} else if msg.Addr.String() != src {
+					atomic.AddUint64(&DefaultSnmp.InErrs, 1)
+					continue
+				}
+
+				if msg.N < s.headerSize+IKCP_OVERHEAD {
+					atomic.AddUint64(&DefaultSnmp.InErrs, 1)
+					continue
+				}
+
+				// source and size has validated
+				s.packetInput(msg.Buffers[0][:msg.N])
+			}
+		} else {
+			// compatibility issue:
+			// for linux kernel<=2.6.32, support for sendmmsg is not available
+			// an error of type os.SyscallError will be returned
+			if operr, ok := err.(*net.OpError); ok {
+				if se, ok := operr.Err.(*os.SyscallError); ok {
+					if se.Syscall == "recvmmsg" {
+						s.defaultReadLoop()
+						return
+					}
+				}
+			}
+			s.notifyReadError(errors.WithStack(err))
+			return
+		}
+	}
+}
+
+// monitor incoming data for all connections of server
+func (l *Listener) monitor() {
+	var xconn batchConn
+	if _, ok := l.conn.(*net.UDPConn); ok {
+		addr, err := net.ResolveUDPAddr("udp", l.conn.LocalAddr().String())
+		if err == nil {
+			if addr.IP.To4() != nil {
+				xconn = ipv4.NewPacketConn(l.conn)
+			} else {
+				xconn = ipv6.NewPacketConn(l.conn)
+			}
+		}
+	}
+
+	// default version
+	if xconn == nil {
+		l.defaultMonitor()
+		return
+	}
+
+	// x/net version
+	msgs := make([]ipv4.Message, batchSize)
+	for k := range msgs {
+		msgs[k].Buffers = [][]byte{make([]byte, mtuLimit)}
+	}
+
+	for {
+		if count, err := xconn.ReadBatch(msgs, 0); err == nil {
+			for i := 0; i < count; i++ {
+				msg := &msgs[i]
+				if msg.N >= l.headerSize+IKCP_OVERHEAD {
+					l.packetInput(msg.Buffers[0][:msg.N], msg.Addr)
+				} else {
+					atomic.AddUint64(&DefaultSnmp.InErrs, 1)
+				}
+			}
+		} else {
+			// compatibility issue:
+			// for linux kernel<=2.6.32, support for sendmmsg is not available
+			// an error of type os.SyscallError will be returned
+			if operr, ok := err.(*net.OpError); ok {
+				if se, ok := operr.Err.(*os.SyscallError); ok {
+					if se.Syscall == "recvmmsg" {
+						l.defaultMonitor()
+						return
+					}
+				}
+			}
+			l.notifyReadError(errors.WithStack(err))
+			return
+		}
+	}
+}