init commit

gate-hk4e/kcp/tx_linux.go

@@ -0,0 +1,102 @@
+//go:build linux
+// +build linux
+
+package kcp
+
+import (
+	"golang.org/x/net/ipv6"
+	"net"
+	"os"
+	"sync/atomic"
+
+	"github.com/pkg/errors"
+	"golang.org/x/net/ipv4"
+)
+
+func (l *Listener) SendEnetNotifyToClient(enet *Enet) {
+	var xconn batchConn
+	_, ok := l.conn.(*net.UDPConn)
+	if !ok {
+		return
+	}
+	localAddr, err := net.ResolveUDPAddr("udp", l.conn.LocalAddr().String())
+	if err != nil {
+		return
+	}
+	if localAddr.IP.To4() != nil {
+		xconn = ipv4.NewPacketConn(l.conn)
+	} else {
+		xconn = ipv6.NewPacketConn(l.conn)
+	}
+
+	// default version
+	if xconn == nil {
+		l.defaultSendEnetNotifyToClient(enet)
+		return
+	}
+
+	remoteAddr, err := net.ResolveUDPAddr("udp", enet.Addr)
+	if err != nil {
+		return
+	}
+
+	data := buildEnet(enet.ConnType, enet.EnetType, enet.ConvId)
+	if data == nil {
+		return
+	}
+
+	_, _ = xconn.WriteBatch([]ipv4.Message{{
+		Buffers: [][]byte{data},
+		Addr:    remoteAddr,
+	}}, 0)
+}
+
+func (s *UDPSession) SendEnetNotify(enet *Enet) {
+	data := buildEnet(enet.ConnType, enet.EnetType, s.GetConv())
+	if data == nil {
+		return
+	}
+	s.tx([]ipv4.Message{{
+		Buffers: [][]byte{data},
+		Addr:    s.remote,
+	}})
+}
+
+func (s *UDPSession) tx(txqueue []ipv4.Message) {
+	// default version
+	if s.xconn == nil || s.xconnWriteError != nil {
+		s.defaultTx(txqueue)
+		return
+	}
+
+	// x/net version
+	nbytes := 0
+	npkts := 0
+	for len(txqueue) > 0 {
+		if n, err := s.xconn.WriteBatch(txqueue, 0); err == nil {
+			for k := range txqueue[:n] {
+				nbytes += len(txqueue[k].Buffers[0])
+			}
+			npkts += n
+			txqueue = txqueue[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 == "sendmmsg" {
+						s.xconnWriteError = se
+						s.defaultTx(txqueue)
+						return
+					}
+				}
+			}
+			s.notifyWriteError(errors.WithStack(err))
+			break
+		}
+	}
+
+	atomic.AddUint64(&DefaultSnmp.OutPkts, uint64(npkts))
+	atomic.AddUint64(&DefaultSnmp.OutBytes, uint64(nbytes))
+}