chore: packet deadline support CreateReadWaiter interface

common/net/deadline/packet_enhance.go

@@ -3,6 +3,7 @@ package deadline
 import (
 	"net"
 	"os"
+	"runtime"
 
 	"github.com/Dreamacro/clash/common/net/packet"
 )
@@ -19,7 +20,10 @@ func NewEnhancePacketConn(pc packet.EnhancePacketConn) packet.EnhancePacketConn
 }
 
 type enhanceReadResult struct {
-	put func()
+	data []byte
+	put  func()
+	addr net.Addr
+	err  error
 }
 
 type enhancePacketConn struct {
@@ -28,21 +32,29 @@ type enhancePacketConn struct {
 }
 
 func (c *enhancePacketConn) WaitReadFrom() (data []byte, put func(), addr net.Addr, err error) {
-	select {
-	case result := <-c.netPacketConn.resultCh:
-		if result != nil {
-			data = result.data
-			put = result.put
-			addr = result.addr
-			err = result.err
-			c.netPacketConn.resultCh <- nil // finish cache read
-			return
-		} else {
-			c.netPacketConn.resultCh <- nil
-			break
+FOR:
+	for {
+		select {
+		case result := <-c.netPacketConn.resultCh:
+			if result != nil {
+				if result, ok := result.(*enhanceReadResult); ok {
+					data = result.data
+					put = result.put
+					addr = result.addr
+					err = result.err
+					c.netPacketConn.resultCh <- nil // finish cache read
+					return
+				}
+				c.netPacketConn.resultCh <- result // another type of read
+				runtime.Gosched()                  // allowing other goroutines to run
+				continue FOR
+			} else {
+				c.netPacketConn.resultCh <- nil
+				break FOR
+			}
+		case <-c.netPacketConn.pipeDeadline.wait():
+			return nil, nil, nil, os.ErrDeadlineExceeded
 		}
-	case <-c.netPacketConn.pipeDeadline.wait():
-		return nil, nil, nil, os.ErrDeadlineExceeded
 	}
 
 	if c.netPacketConn.disablePipe.Load() {
@@ -62,12 +74,10 @@ func (c *enhancePacketConn) WaitReadFrom() (data []byte, put func(), addr net.Ad
 
 func (c *enhancePacketConn) pipeWaitReadFrom() {
 	data, put, addr, err := c.enhancePacketConn.WaitReadFrom()
-	c.netPacketConn.resultCh <- &readResult{
-		data: data,
-		enhanceReadResult: enhanceReadResult{
-			put: put,
-		},
-		addr: addr,
-		err:  err,
-	}
+	result := &enhanceReadResult{}
+	result.data = data
+	result.put = put
+	result.addr = addr
+	result.err = err
+	c.netPacketConn.resultCh <- result
 }