Reset the sniffing buffer when not needed

The sniffing buffer will live as long as the connection is open,
and we should reset it as soon as the application has read all the
sniffed data.

.travis.yml

@@ -3,6 +3,7 @@ language: go
 go:
   - 1.5
   - 1.6
+  - 1.7
   - tip
 
 matrix:

bench_test.go

@@ -20,6 +20,7 @@ import (
 	"net"
 	"sync"
 	"testing"
+	"time"
 
 	"golang.org/x/net/http2"
 )
@@ -43,6 +44,10 @@ func (c *mockConn) Read(b []byte) (n int, err error) {
 	return c.r.Read(b)
 }
 
+func (c *mockConn) SetReadDeadline(time.Time) error {
+	return nil
+}
+
 func discard(l net.Listener) {
 	for {
 		if _, err := l.Accept(); err != nil {

buffer.go

@@ -42,6 +42,10 @@ func (s *bufferedReader) Read(p []byte) (int, error) {
 		bn := copy(p, s.buffer.Bytes()[s.bufferRead:s.bufferSize])
 		s.bufferRead += bn
 		return bn, s.lastErr
+	} else if !s.sniffing && s.buffer.Cap() != 0 {
+		// We don't need the buffer anymore.
+		// Reset it to release the internal slice.
+		s.buffer = bytes.Buffer{}
 	}
 
 	// If there is nothing more to return in the sniffed buffer, read from the

cmux.go

@@ -19,6 +19,7 @@ import (
 	"io"
 	"net"
 	"sync"
+	"time"
 )
 
 // Matcher matches a connection based on its content.
@@ -60,13 +61,17 @@ func (e errListenerClosed) Timeout() bool   { return false }
 // listener is closed.
 var ErrListenerClosed = errListenerClosed("mux: listener closed")
 
+// for readability of readTimeout
+var noTimeout time.Duration
+
 // New instantiates a new connection multiplexer.
 func New(l net.Listener) CMux {
 	return &cMux{
-		root:   l,
-		bufLen: 1024,
-		errh:   func(_ error) bool { return true },
-		donec:  make(chan struct{}),
+		root:        l,
+		bufLen:      1024,
+		errh:        func(_ error) bool { return true },
+		donec:       make(chan struct{}),
+		readTimeout: noTimeout,
 	}
 }
 
@@ -90,6 +95,8 @@ type CMux interface {
 	Serve() error
 	// HandleError registers an error handler that handles listener errors.
 	HandleError(ErrorHandler)
+	// sets a timeout for the read of matchers
+	SetReadTimeout(time.Duration)
 }
 
 type matchersListener struct {
@@ -98,11 +105,12 @@ type matchersListener struct {
 }
 
 type cMux struct {
-	root   net.Listener
-	bufLen int
-	errh   ErrorHandler
-	donec  chan struct{}
-	sls    []matchersListener
+	root        net.Listener
+	bufLen      int
+	errh        ErrorHandler
+	donec       chan struct{}
+	sls         []matchersListener
+	readTimeout time.Duration
 }
 
 func matchersToMatchWriters(matchers []Matcher) []MatchWriter {
@@ -129,6 +137,10 @@ func (m *cMux) MatchWithWriters(matchers ...MatchWriter) net.Listener {
 	return ml
 }
 
+func (m *cMux) SetReadTimeout(t time.Duration) {
+	m.readTimeout = t
+}
+
 func (m *cMux) Serve() error {
 	var wg sync.WaitGroup
 
@@ -163,11 +175,17 @@ func (m *cMux) serve(c net.Conn, donec <-chan struct{}, wg *sync.WaitGroup) {
 	defer wg.Done()
 
 	muc := newMuxConn(c)
+	if m.readTimeout > noTimeout {
+		_ = c.SetReadDeadline(time.Now().Add(m.readTimeout))
+	}
 	for _, sl := range m.sls {
 		for _, s := range sl.ss {
 			matched := s(muc.Conn, muc.startSniffing())
 			if matched {
 				muc.doneSniffing()
+				if m.readTimeout > noTimeout {
+					_ = c.SetReadDeadline(time.Time{})
+				}
 				select {
 				case sl.l.connc <- muc:
 				case <-donec:

cmux_test.go

@@ -15,10 +15,12 @@
 package cmux
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
+	"log"
 	"net"
 	"net/http"
 	"net/rpc"
@@ -31,6 +33,7 @@ import (
 	"time"
 
 	"golang.org/x/net/http2"
+	"golang.org/x/net/http2/hpack"
 )
 
 const (
@@ -73,14 +76,17 @@ func (l *chanListener) Accept() (net.Conn, error) {
 }
 
 func testListener(t *testing.T) (net.Listener, func()) {
-	l, err := net.Listen("tcp", ":0")
+	l, err := net.Listen("tcp4", ":0")
 	if err != nil {
 		t.Fatal(err)
 	}
+	var once sync.Once
 	return l, func() {
-		if err := l.Close(); err != nil {
-			t.Fatal(err)
-		}
+		once.Do(func() {
+			if err := l.Close(); err != nil {
+				t.Fatal(err)
+			}
+		})
 	}
 }
 
@@ -181,6 +187,84 @@ func runTestRPCClient(t *testing.T, addr net.Addr) {
 	}
 }
 
+const (
+	handleHTTP1Close   = 1
+	handleHTTP1Request = 2
+	handleAnyClose     = 3
+	handleAnyRequest   = 4
+)
+
+func TestTimeout(t *testing.T) {
+	defer leakCheck(t)()
+	lis, Close := testListener(t)
+	defer Close()
+	result := make(chan int, 5)
+	testDuration := time.Millisecond * 100
+	m := New(lis)
+	m.SetReadTimeout(testDuration)
+	http1 := m.Match(HTTP1Fast())
+	any := m.Match(Any())
+	go func() {
+		_ = m.Serve()
+	}()
+	go func() {
+		con, err := http1.Accept()
+		if err != nil {
+			result <- handleHTTP1Close
+		} else {
+			_, _ = con.Write([]byte("http1"))
+			_ = con.Close()
+			result <- handleHTTP1Request
+		}
+	}()
+	go func() {
+		con, err := any.Accept()
+		if err != nil {
+			result <- handleAnyClose
+		} else {
+			_, _ = con.Write([]byte("any"))
+			_ = con.Close()
+			result <- handleAnyRequest
+		}
+	}()
+	time.Sleep(testDuration) // wait to prevent timeouts on slow test-runners
+	client, err := net.Dial("tcp", lis.Addr().String())
+	if err != nil {
+		log.Fatal("testTimeout client failed: ", err)
+	}
+	defer func() {
+		_ = client.Close()
+	}()
+	time.Sleep(testDuration / 2)
+	if len(result) != 0 {
+		log.Print("tcp ")
+		t.Fatal("testTimeout failed: accepted to fast: ", len(result))
+	}
+	_ = client.SetReadDeadline(time.Now().Add(testDuration * 3))
+	buffer := make([]byte, 10)
+	rl, err := client.Read(buffer)
+	if err != nil {
+		t.Fatal("testTimeout failed: client error: ", err, rl)
+	}
+	Close()
+	if rl != 3 {
+		log.Print("testTimeout failed: response from wrong sevice ", rl)
+	}
+	if string(buffer[0:3]) != "any" {
+		log.Print("testTimeout failed: response from wrong sevice ")
+	}
+	time.Sleep(testDuration * 2)
+	if len(result) != 2 {
+		t.Fatal("testTimeout failed: accepted to less: ", len(result))
+	}
+	if a := <-result; a != handleAnyRequest {
+		t.Fatal("testTimeout failed: any rule did not match")
+	}
+	if a := <-result; a != handleHTTP1Close {
+		t.Fatal("testTimeout failed: no close an http rule")
+	}
+}
+
 func TestRead(t *testing.T) {
 	defer leakCheck(t)()
 	errCh := make(chan error)
@@ -312,6 +396,72 @@ func TestHTTP2(t *testing.T) {
 	}
 }
 
+func TestHTTP2MatchHeaderField(t *testing.T) {
+	defer leakCheck(t)()
+	errCh := make(chan error)
+	defer func() {
+		select {
+		case err := <-errCh:
+			t.Fatal(err)
+		default:
+		}
+	}()
+	name := "name"
+	value := "value"
+	writer, reader := net.Pipe()
+	go func() {
+		if _, err := io.WriteString(writer, http2.ClientPreface); err != nil {
+			t.Fatal(err)
+		}
+		var buf bytes.Buffer
+		enc := hpack.NewEncoder(&buf)
+		if err := enc.WriteField(hpack.HeaderField{Name: name, Value: value}); err != nil {
+			t.Fatal(err)
+		}
+		framer := http2.NewFramer(writer, nil)
+		err := framer.WriteHeaders(http2.HeadersFrameParam{
+			StreamID:      1,
+			BlockFragment: buf.Bytes(),
+			EndStream:     true,
+			EndHeaders:    true,
+		})
+		if err != nil {
+			t.Fatal(err)
+		}
+		if err := writer.Close(); err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	l := newChanListener()
+	l.connCh <- reader
+	muxl := New(l)
+	// Register a bogus matcher that only reads one byte.
+	muxl.Match(func(r io.Reader) bool {
+		var b [1]byte
+		_, _ = r.Read(b[:])
+		return false
+	})
+	// Create a matcher that cannot match the response.
+	muxl.Match(HTTP2HeaderField(name, "another"+value))
+	// Then match with the expected field.
+	h2l := muxl.Match(HTTP2HeaderField(name, value))
+	go safeServe(errCh, muxl)
+	muxedConn, err := h2l.Accept()
+	close(l.connCh)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var b [len(http2.ClientPreface)]byte
+	// We have the sniffed buffer first...
+	if _, err := muxedConn.Read(b[:]); err == io.EOF {
+		t.Fatal(err)
+	}
+	if string(b[:]) != http2.ClientPreface {
+		t.Errorf("got unexpected read %s, expected %s", b, http2.ClientPreface)
+	}
+}
+
 func TestHTTPGoRPC(t *testing.T) {
 	defer leakCheck(t)()
 	errCh := make(chan error)
@@ -439,6 +589,7 @@ func interestingGoroutines() (gs []string) {
 		}
 
 		if stack == "" ||
+			strings.Contains(stack, "main.main()") ||
 			strings.Contains(stack, "testing.Main(") ||
 			strings.Contains(stack, "runtime.goexit") ||
 			strings.Contains(stack, "created by runtime.gc") ||

matchers.go

@@ -144,10 +144,14 @@ func matchHTTP2Field(w io.Writer, r io.Reader, name, value string) (matched bool
 		return false
 	}
 
+	done := false
 	framer := http2.NewFramer(w, r)
 	hdec := hpack.NewDecoder(uint32(4<<10), func(hf hpack.HeaderField) {
-		if hf.Name == name && hf.Value == value {
-			matched = true
+		if hf.Name == name {
+			done = true
+			if hf.Value == value {
+				matched = true
+			}
 		}
 	})
 	for {
@@ -161,17 +165,20 @@ func matchHTTP2Field(w io.Writer, r io.Reader, name, value string) (matched bool
 			if err := framer.WriteSettings(); err != nil {
 				return false
 			}
+		case *http2.ContinuationFrame:
+			if _, err := hdec.Write(f.HeaderBlockFragment()); err != nil {
+				return false
+			}
+			done = done || f.FrameHeader.Flags&http2.FlagHeadersEndHeaders != 0
 		case *http2.HeadersFrame:
 			if _, err := hdec.Write(f.HeaderBlockFragment()); err != nil {
 				return false
 			}
-			if matched {
-				return true
-			}
+			done = done || f.FrameHeader.Flags&http2.FlagHeadersEndHeaders != 0
+		}
 
-			if f.FrameHeader.Flags&http2.FlagHeadersEndHeaders != 0 {
-				return false
-			}
+		if done {
+			return matched
 		}
 	}
 }