Update dependencies

6 files changed, 363 insertions, 162 deletions

diff --git a/vendor/golang.org/x/net/http2/client_conn_pool.go b/vendor/golang.org/x/net/http2/client_conn_pool.go
index cb34cc2..b139412 100644
--- a/vendor/golang.org/x/net/http2/client_conn_pool.go
+++ b/vendor/golang.org/x/net/http2/client_conn_pool.go
@@ -55,11 +55,11 @@ const (
 func (p *clientConnPool) getClientConn(req *http.Request, addr string, dialOnMiss bool) (*ClientConn, error) {
 	if isConnectionCloseRequest(req) && dialOnMiss {
 		// It gets its own connection.
-		cc, err := p.t.dialClientConn(addr)
+		const singleUse = true
+		cc, err := p.t.dialClientConn(addr, singleUse)
 		if err != nil {
 			return nil, err
 		}
-		cc.singleUse = true
 		return cc, nil
 	}
 	p.mu.Lock()
@@ -104,7 +104,8 @@ func (p *clientConnPool) getStartDialLocked(addr string) *dialCall {
 
 // run in its own goroutine.
 func (c *dialCall) dial(addr string) {
-	c.res, c.err = c.p.t.dialClientConn(addr)
+	const singleUse = false // shared conn
+	c.res, c.err = c.p.t.dialClientConn(addr, singleUse)
 	close(c.done)
 
 	c.p.mu.Lock()
diff --git a/vendor/golang.org/x/net/http2/errors.go b/vendor/golang.org/x/net/http2/errors.go
index 71a4e29..20fd762 100644
--- a/vendor/golang.org/x/net/http2/errors.go
+++ b/vendor/golang.org/x/net/http2/errors.go
@@ -64,9 +64,17 @@ func (e ConnectionError) Error() string { return fmt.Sprintf("connection error:
 type StreamError struct {
 	StreamID uint32
 	Code     ErrCode
+	Cause    error // optional additional detail
+}
+
+func streamError(id uint32, code ErrCode) StreamError {
+	return StreamError{StreamID: id, Code: code}
 }
 
 func (e StreamError) Error() string {
+	if e.Cause != nil {
+		return fmt.Sprintf("stream error: stream ID %d; %v; %v", e.StreamID, e.Code, e.Cause)
+	}
 	return fmt.Sprintf("stream error: stream ID %d; %v", e.StreamID, e.Code)
 }
 
diff --git a/vendor/golang.org/x/net/http2/frame.go b/vendor/golang.org/x/net/http2/frame.go
index 981d407..c9b09bb 100644
--- a/vendor/golang.org/x/net/http2/frame.go
+++ b/vendor/golang.org/x/net/http2/frame.go
@@ -594,6 +594,7 @@ func parseDataFrame(fh FrameHeader, payload []byte) (Frame, error) {
 var (
 	errStreamID    = errors.New("invalid stream ID")
 	errDepStreamID = errors.New("invalid dependent stream ID")
+	errPadLength   = errors.New("pad length too large")
 )
 
 func validStreamIDOrZero(streamID uint32) bool {
@@ -607,18 +608,40 @@ func validStreamID(streamID uint32) bool {
 // WriteData writes a DATA frame.
 //
 // It will perform exactly one Write to the underlying Writer.
-// It is the caller's responsibility to not call other Write methods concurrently.
+// It is the caller's responsibility not to violate the maximum frame size
+// and to not call other Write methods concurrently.
 func (f *Framer) WriteData(streamID uint32, endStream bool, data []byte) error {
-	// TODO: ignoring padding for now. will add when somebody cares.
+	return f.WriteDataPadded(streamID, endStream, data, nil)
+}
+
+// WriteData writes a DATA frame with optional padding.
+//
+// If pad is nil, the padding bit is not sent.
+// The length of pad must not exceed 255 bytes.
+//
+// It will perform exactly one Write to the underlying Writer.
+// It is the caller's responsibility not to violate the maximum frame size
+// and to not call other Write methods concurrently.
+func (f *Framer) WriteDataPadded(streamID uint32, endStream bool, data, pad []byte) error {
 	if !validStreamID(streamID) && !f.AllowIllegalWrites {
 		return errStreamID
 	}
+	if len(pad) > 255 {
+		return errPadLength
+	}
 	var flags Flags
 	if endStream {
 		flags |= FlagDataEndStream
 	}
+	if pad != nil {
+		flags |= FlagDataPadded
+	}
 	f.startWrite(FrameData, flags, streamID)
+	if pad != nil {
+		f.wbuf = append(f.wbuf, byte(len(pad)))
+	}
 	f.wbuf = append(f.wbuf, data...)
+	f.wbuf = append(f.wbuf, pad...)
 	return f.endWrite()
 }
 
@@ -840,7 +863,7 @@ func parseWindowUpdateFrame(fh FrameHeader, p []byte) (Frame, error) {
 		if fh.StreamID == 0 {
 			return nil, ConnectionError(ErrCodeProtocol)
 		}
-		return nil, StreamError{fh.StreamID, ErrCodeProtocol}
+		return nil, streamError(fh.StreamID, ErrCodeProtocol)
 	}
 	return &WindowUpdateFrame{
 		FrameHeader: fh,
@@ -921,7 +944,7 @@ func parseHeadersFrame(fh FrameHeader, p []byte) (_ Frame, err error) {
 		}
 	}
 	if len(p)-int(padLength) <= 0 {
-		return nil, StreamError{fh.StreamID, ErrCodeProtocol}
+		return nil, streamError(fh.StreamID, ErrCodeProtocol)
 	}
 	hf.headerFragBuf = p[:len(p)-int(padLength)]
 	return hf, nil
@@ -1396,6 +1419,9 @@ func (fr *Framer) readMetaFrame(hf *HeadersFrame) (*MetaHeadersFrame, error) {
 	hdec.SetEmitEnabled(true)
 	hdec.SetMaxStringLength(fr.maxHeaderStringLen())
 	hdec.SetEmitFunc(func(hf hpack.HeaderField) {
+		if VerboseLogs && logFrameReads {
+			log.Printf("http2: decoded hpack field %+v", hf)
+		}
 		if !httplex.ValidHeaderFieldValue(hf.Value) {
 			invalid = headerFieldValueError(hf.Value)
 		}
@@ -1454,11 +1480,17 @@ func (fr *Framer) readMetaFrame(hf *HeadersFrame) (*MetaHeadersFrame, error) {
 	}
 	if invalid != nil {
 		fr.errDetail = invalid
-		return nil, StreamError{mh.StreamID, ErrCodeProtocol}
+		if VerboseLogs {
+			log.Printf("http2: invalid header: %v", invalid)
+		}
+		return nil, StreamError{mh.StreamID, ErrCodeProtocol, invalid}
 	}
 	if err := mh.checkPseudos(); err != nil {
 		fr.errDetail = err
-		return nil, StreamError{mh.StreamID, ErrCodeProtocol}
+		if VerboseLogs {
+			log.Printf("http2: invalid pseudo headers: %v", err)
+		}
+		return nil, StreamError{mh.StreamID, ErrCodeProtocol, err}
 	}
 	return mh, nil
 }
diff --git a/vendor/golang.org/x/net/http2/http2.go b/vendor/golang.org/x/net/http2/http2.go
index 0173aed..401923b 100644
--- a/vendor/golang.org/x/net/http2/http2.go
+++ b/vendor/golang.org/x/net/http2/http2.go
@@ -13,7 +13,8 @@
 // See https://http2.github.io/ for more information on HTTP/2.
 //
 // See https://http2.golang.org/ for a test server running this code.
-package http2
+//
+package http2 // import "golang.org/x/net/http2"
 
 import (
 	"bufio"
@@ -349,3 +350,13 @@ func (s *sorter) SortStrings(ss []string) {
 	sort.Sort(s)
 	s.v = save
 }
+
+// validPseudoPath reports whether v is a valid :path pseudo-header
+// value. It must be a non-empty string starting with '/', and not
+// start with two slashes.
+// For now this is only used a quick check for deciding when to clean
+// up Opaque URLs before sending requests from the Transport.
+// See golang.org/issue/16847
+func validPseudoPath(v string) bool {
+	return len(v) > 0 && v[0] == '/' && (len(v) == 1 || v[1] != '/')
+}
diff --git a/vendor/golang.org/x/net/http2/server.go b/vendor/golang.org/x/net/http2/server.go
index f368738..8206fa7 100644
--- a/vendor/golang.org/x/net/http2/server.go
+++ b/vendor/golang.org/x/net/http2/server.go
@@ -922,7 +922,7 @@ func (sc *serverConn) wroteFrame(res frameWriteResult) {
 			// state here anyway, after telling the peer
 			// we're hanging up on them.
 			st.state = stateHalfClosedLocal // won't last long, but necessary for closeStream via resetStream
-			errCancel := StreamError{st.id, ErrCodeCancel}
+			errCancel := streamError(st.id, ErrCodeCancel)
 			sc.resetStream(errCancel)
 		case stateHalfClosedRemote:
 			sc.closeStream(st, errHandlerComplete)
@@ -1133,7 +1133,7 @@ func (sc *serverConn) processWindowUpdate(f *WindowUpdateFrame) error {
 			return nil
 		}
 		if !st.flow.add(int32(f.Increment)) {
-			return StreamError{f.StreamID, ErrCodeFlowControl}
+			return streamError(f.StreamID, ErrCodeFlowControl)
 		}
 	default: // connection-level flow control
 		if !sc.flow.add(int32(f.Increment)) {
@@ -1159,7 +1159,7 @@ func (sc *serverConn) processResetStream(f *RSTStreamFrame) error {
 	if st != nil {
 		st.gotReset = true
 		st.cancelCtx()
-		sc.closeStream(st, StreamError{f.StreamID, f.ErrCode})
+		sc.closeStream(st, streamError(f.StreamID, f.ErrCode))
 	}
 	return nil
 }
@@ -1176,6 +1176,10 @@ func (sc *serverConn) closeStream(st *stream, err error) {
 	}
 	delete(sc.streams, st.id)
 	if p := st.body; p != nil {
+		// Return any buffered unread bytes worth of conn-level flow control.
+		// See golang.org/issue/16481
+		sc.sendWindowUpdate(nil, p.Len())
+
 		p.CloseWithError(err)
 	}
 	st.cw.Close() // signals Handler's CloseNotifier, unblocks writes, etc
@@ -1277,6 +1281,8 @@ func (sc *serverConn) processSettingInitialWindowSize(val uint32) error {
 
 func (sc *serverConn) processData(f *DataFrame) error {
 	sc.serveG.check()
+	data := f.Data()
+
 	// "If a DATA frame is received whose stream is not in "open"
 	// or "half closed (local)" state, the recipient MUST respond
 	// with a stream error (Section 5.4.2) of type STREAM_CLOSED."
@@ -1288,32 +1294,55 @@ func (sc *serverConn) processData(f *DataFrame) error {
 		// the http.Handler returned, so it's done reading &
 		// done writing). Try to stop the client from sending
 		// more DATA.
-		return StreamError{id, ErrCodeStreamClosed}
+
+		// But still enforce their connection-level flow control,
+		// and return any flow control bytes since we're not going
+		// to consume them.
+		if sc.inflow.available() < int32(f.Length) {
+			return streamError(id, ErrCodeFlowControl)
+		}
+		// Deduct the flow control from inflow, since we're
+		// going to immediately add it back in
+		// sendWindowUpdate, which also schedules sending the
+		// frames.
+		sc.inflow.take(int32(f.Length))
+		sc.sendWindowUpdate(nil, int(f.Length)) // conn-level
+
+		return streamError(id, ErrCodeStreamClosed)
 	}
 	if st.body == nil {
 		panic("internal error: should have a body in this state")
 	}
-	data := f.Data()
 
 	// Sender sending more than they'd declared?
 	if st.declBodyBytes != -1 && st.bodyBytes+int64(len(data)) > st.declBodyBytes {
 		st.body.CloseWithError(fmt.Errorf("sender tried to send more than declared Content-Length of %d bytes", st.declBodyBytes))
-		return StreamError{id, ErrCodeStreamClosed}
+		return streamError(id, ErrCodeStreamClosed)
 	}
-	if len(data) > 0 {
+	if f.Length > 0 {
 		// Check whether the client has flow control quota.
-		if int(st.inflow.available()) < len(data) {
-			return StreamError{id, ErrCodeFlowControl}
+		if st.inflow.available() < int32(f.Length) {
+			return streamError(id, ErrCodeFlowControl)
 		}
-		st.inflow.take(int32(len(data)))
-		wrote, err := st.body.Write(data)
-		if err != nil {
-			return StreamError{id, ErrCodeStreamClosed}
+		st.inflow.take(int32(f.Length))
+
+		if len(data) > 0 {
+			wrote, err := st.body.Write(data)
+			if err != nil {
+				return streamError(id, ErrCodeStreamClosed)
+			}
+			if wrote != len(data) {
+				panic("internal error: bad Writer")
+			}
+			st.bodyBytes += int64(len(data))
 		}
-		if wrote != len(data) {
-			panic("internal error: bad Writer")
+
+		// Return any padded flow control now, since we won't
+		// refund it later on body reads.
+		if pad := int32(f.Length) - int32(len(data)); pad > 0 {
+			sc.sendWindowUpdate32(nil, pad)
+			sc.sendWindowUpdate32(st, pad)
 		}
-		st.bodyBytes += int64(len(data))
 	}
 	if f.StreamEnded() {
 		st.endStream()
@@ -1417,14 +1446,14 @@ func (sc *serverConn) processHeaders(f *MetaHeadersFrame) error {
 		// REFUSED_STREAM."
 		if sc.unackedSettings == 0 {
 			// They should know better.
-			return StreamError{st.id, ErrCodeProtocol}
+			return streamError(st.id, ErrCodeProtocol)
 		}
 		// Assume it's a network race, where they just haven't
 		// received our last SETTINGS update. But actually
 		// this can't happen yet, because we don't yet provide
 		// a way for users to adjust server parameters at
 		// runtime.
-		return StreamError{st.id, ErrCodeRefusedStream}
+		return streamError(st.id, ErrCodeRefusedStream)
 	}
 
 	rw, req, err := sc.newWriterAndRequest(st, f)
@@ -1458,11 +1487,11 @@ func (st *stream) processTrailerHeaders(f *MetaHeadersFrame) error {
 	}
 	st.gotTrailerHeader = true
 	if !f.StreamEnded() {
-		return StreamError{st.id, ErrCodeProtocol}
+		return streamError(st.id, ErrCodeProtocol)
 	}
 
 	if len(f.PseudoFields()) > 0 {
-		return StreamError{st.id, ErrCodeProtocol}
+		return streamError(st.id, ErrCodeProtocol)
 	}
 	if st.trailer != nil {
 		for _, hf := range f.RegularFields() {
@@ -1471,7 +1500,7 @@ func (st *stream) processTrailerHeaders(f *MetaHeadersFrame) error {
 				// TODO: send more details to the peer somehow. But http2 has
 				// no way to send debug data at a stream level. Discuss with
 				// HTTP folk.
-				return StreamError{st.id, ErrCodeProtocol}
+				return streamError(st.id, ErrCodeProtocol)
 			}
 			st.trailer[key] = append(st.trailer[key], hf.Value)
 		}
@@ -1532,7 +1561,7 @@ func (sc *serverConn) newWriterAndRequest(st *stream, f *MetaHeadersFrame) (*res
 	isConnect := method == "CONNECT"
 	if isConnect {
 		if path != "" || scheme != "" || authority == "" {
-			return nil, nil, StreamError{f.StreamID, ErrCodeProtocol}
+			return nil, nil, streamError(f.StreamID, ErrCodeProtocol)
 		}
 	} else if method == "" || path == "" ||
 		(scheme != "https" && scheme != "http") {
@@ -1546,13 +1575,13 @@ func (sc *serverConn) newWriterAndRequest(st *stream, f *MetaHeadersFrame) (*res
 		// "All HTTP/2 requests MUST include exactly one valid
 		// value for the :method, :scheme, and :path
 		// pseudo-header fields"
-		return nil, nil, StreamError{f.StreamID, ErrCodeProtocol}
+		return nil, nil, streamError(f.StreamID, ErrCodeProtocol)
 	}
 
 	bodyOpen := !f.StreamEnded()
 	if method == "HEAD" && bodyOpen {
 		// HEAD requests can't have bodies
-		return nil, nil, StreamError{f.StreamID, ErrCodeProtocol}
+		return nil, nil, streamError(f.StreamID, ErrCodeProtocol)
 	}
 	var tlsState *tls.ConnectionState // nil if not scheme https
 
@@ -1610,7 +1639,7 @@ func (sc *serverConn) newWriterAndRequest(st *stream, f *MetaHeadersFrame) (*res
 		var err error
 		url_, err = url.ParseRequestURI(path)
 		if err != nil {
-			return nil, nil, StreamError{f.StreamID, ErrCodeProtocol}
+			return nil, nil, streamError(f.StreamID, ErrCodeProtocol)
 		}
 		requestURI = path
 	}
diff --git a/vendor/golang.org/x/net/http2/transport.go b/vendor/golang.org/x/net/http2/transport.go
index de3f5fe..bcd27ae 100644
--- a/vendor/golang.org/x/net/http2/transport.go
+++ b/vendor/golang.org/x/net/http2/transport.go
@@ -16,6 +16,7 @@ import (
 	"io"
 	"io/ioutil"
 	"log"
+	"math"
 	"net"
 	"net/http"
 	"sort"
@@ -148,27 +149,28 @@ type ClientConn struct {
 	readerDone chan struct{} // closed on error
 	readerErr  error         // set before readerDone is closed
 
-	mu           sync.Mutex // guards following
-	cond         *sync.Cond // hold mu; broadcast on flow/closed changes
-	flow         flow       // our conn-level flow control quota (cs.flow is per stream)
-	inflow       flow       // peer's conn-level flow control
-	closed       bool
-	goAway       *GoAwayFrame             // if non-nil, the GoAwayFrame we received
-	goAwayDebug  string                   // goAway frame's debug data, retained as a string
-	streams      map[uint32]*clientStream // client-initiated
-	nextStreamID uint32
-	bw           *bufio.Writer
-	br           *bufio.Reader
-	fr           *Framer
-	lastActive   time.Time
-
-	// Settings from peer:
+	mu              sync.Mutex // guards following
+	cond            *sync.Cond // hold mu; broadcast on flow/closed changes
+	flow            flow       // our conn-level flow control quota (cs.flow is per stream)
+	inflow          flow       // peer's conn-level flow control
+	closed          bool
+	wantSettingsAck bool                     // we sent a SETTINGS frame and haven't heard back
+	goAway          *GoAwayFrame             // if non-nil, the GoAwayFrame we received
+	goAwayDebug     string                   // goAway frame's debug data, retained as a string
+	streams         map[uint32]*clientStream // client-initiated
+	nextStreamID    uint32
+	bw              *bufio.Writer
+	br              *bufio.Reader
+	fr              *Framer
+	lastActive      time.Time
+	// Settings from peer: (also guarded by mu)
 	maxFrameSize         uint32
 	maxConcurrentStreams uint32
 	initialWindowSize    uint32
-	hbuf                 bytes.Buffer // HPACK encoder writes into this
-	henc                 *hpack.Encoder
-	freeBuf              [][]byte
+
+	hbuf    bytes.Buffer // HPACK encoder writes into this
+	henc    *hpack.Encoder
+	freeBuf [][]byte
 
 	wmu  sync.Mutex // held while writing; acquire AFTER mu if holding both
 	werr error      // first write error that has occurred
@@ -339,7 +341,7 @@ func shouldRetryRequest(req *http.Request, err error) bool {
 	return err == errClientConnUnusable
 }
 
-func (t *Transport) dialClientConn(addr string) (*ClientConn, error) {
+func (t *Transport) dialClientConn(addr string, singleUse bool) (*ClientConn, error) {
 	host, _, err := net.SplitHostPort(addr)
 	if err != nil {
 		return nil, err
@@ -348,7 +350,7 @@ func (t *Transport) dialClientConn(addr string) (*ClientConn, error) {
 	if err != nil {
 		return nil, err
 	}
-	return t.NewClientConn(tconn)
+	return t.newClientConn(tconn, singleUse)
 }
 
 func (t *Transport) newTLSConfig(host string) *tls.Config {
@@ -409,14 +411,10 @@ func (t *Transport) expectContinueTimeout() time.Duration {
 }
 
 func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) {
-	if VerboseLogs {
-		t.vlogf("http2: Transport creating client conn to %v", c.RemoteAddr())
-	}
-	if _, err := c.Write(clientPreface); err != nil {
-		t.vlogf("client preface write error: %v", err)
-		return nil, err
-	}
+	return t.newClientConn(c, false)
+}
 
+func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, error) {
 	cc := &ClientConn{
 		t:                    t,
 		tconn:                c,
@@ -426,7 +424,13 @@ func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) {
 		initialWindowSize:    65535,    // spec default
 		maxConcurrentStreams: 1000,     // "infinite", per spec. 1000 seems good enough.
 		streams:              make(map[uint32]*clientStream),
+		singleUse:            singleUse,
+		wantSettingsAck:      true,
+	}
+	if VerboseLogs {
+		t.vlogf("http2: Transport creating client conn %p to %v", cc, c.RemoteAddr())
 	}
+
 	cc.cond = sync.NewCond(&cc.mu)
 	cc.flow.add(int32(initialWindowSize))
 
@@ -454,6 +458,8 @@ func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) {
 	if max := t.maxHeaderListSize(); max != 0 {
 		initialSettings = append(initialSettings, Setting{ID: SettingMaxHeaderListSize, Val: max})
 	}
+
+	cc.bw.Write(clientPreface)
 	cc.fr.WriteSettings(initialSettings...)
 	cc.fr.WriteWindowUpdate(0, transportDefaultConnFlow)
 	cc.inflow.add(transportDefaultConnFlow + initialWindowSize)
@@ -462,33 +468,6 @@ func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) {
 		return nil, cc.werr
 	}
 
-	// Read the obligatory SETTINGS frame
-	f, err := cc.fr.ReadFrame()
-	if err != nil {
-		return nil, err
-	}
-	sf, ok := f.(*SettingsFrame)
-	if !ok {
-		return nil, fmt.Errorf("expected settings frame, got: %T", f)
-	}
-	cc.fr.WriteSettingsAck()
-	cc.bw.Flush()
-
-	sf.ForeachSetting(func(s Setting) error {
-		switch s.ID {
-		case SettingMaxFrameSize:
-			cc.maxFrameSize = s.Val
-		case SettingMaxConcurrentStreams:
-			cc.maxConcurrentStreams = s.Val
-		case SettingInitialWindowSize:
-			cc.initialWindowSize = s.Val
-		default:
-			// TODO(bradfitz): handle more; at least SETTINGS_HEADER_TABLE_SIZE?
-			t.vlogf("Unhandled Setting: %v", s)
-		}
-		return nil
-	})
-
 	go cc.readLoop()
 	return cc, nil
 }
@@ -521,7 +500,7 @@ func (cc *ClientConn) canTakeNewRequestLocked() bool {
 	}
 	return cc.goAway == nil && !cc.closed &&
 		int64(len(cc.streams)+1) < int64(cc.maxConcurrentStreams) &&
-		cc.nextStreamID < 2147483647
+		cc.nextStreamID < math.MaxInt32
 }
 
 func (cc *ClientConn) closeIfIdle() {
@@ -531,9 +510,13 @@ func (cc *ClientConn) closeIfIdle() {
 		return
 	}
 	cc.closed = true
+	nextID := cc.nextStreamID
 	// TODO: do clients send GOAWAY too? maybe? Just Close:
 	cc.mu.Unlock()
 
+	if VerboseLogs {
+		cc.vlogf("http2: Transport closing idle conn %p (forSingleUse=%v, maxStream=%v)", cc, cc.singleUse, nextID-2)
+	}
 	cc.tconn.Close()
 }
 
@@ -639,15 +622,18 @@ func bodyAndLength(req *http.Request) (body io.Reader, contentLen int64) {
 	// We have a body but a zero content length. Test to see if
 	// it's actually zero or just unset.
 	var buf [1]byte
-	n, rerr := io.ReadFull(body, buf[:])
+	n, rerr := body.Read(buf[:])
 	if rerr != nil && rerr != io.EOF {
 		return errorReader{rerr}, -1
 	}
 	if n == 1 {
 		// Oh, guess there is data in this Body Reader after all.
 		// The ContentLength field just wasn't set.
-		// Stich the Body back together again, re-attaching our
+		// Stitch the Body back together again, re-attaching our
 		// consumed byte.
+		if rerr == io.EOF {
+			return bytes.NewReader(buf[:]), 1
+		}
 		return io.MultiReader(bytes.NewReader(buf[:]), body), -1
 	}
 	// Body is actually zero bytes.
@@ -747,30 +733,34 @@ func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) {
 	bodyWritten := false
 	ctx := reqContext(req)
 
+	handleReadLoopResponse := func(re resAndError) (*http.Response, error) {
+		res := re.res
+		if re.err != nil || res.StatusCode > 299 {
+			// On error or status code 3xx, 4xx, 5xx, etc abort any
+			// ongoing write, assuming that the server doesn't care
+			// about our request body. If the server replied with 1xx or
+			// 2xx, however, then assume the server DOES potentially
+			// want our body (e.g. full-duplex streaming:
+			// golang.org/issue/13444). If it turns out the server
+			// doesn't, they'll RST_STREAM us soon enough.  This is a
+			// heuristic to avoid adding knobs to Transport.  Hopefully
+			// we can keep it.
+			bodyWriter.cancel()
+			cs.abortRequestBodyWrite(errStopReqBodyWrite)
+		}
+		if re.err != nil {
+			cc.forgetStreamID(cs.ID)
+			return nil, re.err
+		}
+		res.Request = req
+		res.TLS = cc.tlsState
+		return res, nil
+	}
+
 	for {
 		select {
 		case re := <-readLoopResCh:
-			res := re.res
-			if re.err != nil || res.StatusCode > 299 {
-				// On error or status code 3xx, 4xx, 5xx, etc abort any
-				// ongoing write, assuming that the server doesn't care
-				// about our request body. If the server replied with 1xx or
-				// 2xx, however, then assume the server DOES potentially
-				// want our body (e.g. full-duplex streaming:
-				// golang.org/issue/13444). If it turns out the server
-				// doesn't, they'll RST_STREAM us soon enough.  This is a
-				// heuristic to avoid adding knobs to Transport.  Hopefully
-				// we can keep it.
-				bodyWriter.cancel()
-				cs.abortRequestBodyWrite(errStopReqBodyWrite)
-			}
-			if re.err != nil {
-				cc.forgetStreamID(cs.ID)
-				return nil, re.err
-			}
-			res.Request = req
-			res.TLS = cc.tlsState
-			return res, nil
+			return handleReadLoopResponse(re)
 		case <-respHeaderTimer:
 			cc.forgetStreamID(cs.ID)
 			if !hasBody || bodyWritten {
@@ -804,6 +794,12 @@ func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) {
 			// forgetStreamID.
 			return nil, cs.resetErr
 		case err := <-bodyWriter.resc:
+			// Prefer the read loop's response, if available. Issue 16102.
+			select {
+			case re := <-readLoopResCh:
+				return handleReadLoopResponse(re)
+			default:
+			}
 			if err != nil {
 				return nil, err
 			}
@@ -908,10 +904,11 @@ func (cs *clientStream) writeRequestBody(body io.Reader, bodyCloser io.Closer) (
 			err = cc.fr.WriteData(cs.ID, sentEnd, data)
 			if err == nil {
 				// TODO(bradfitz): this flush is for latency, not bandwidth.
-				// Most requests won't need this. Make this opt-in or opt-out?
-				// Use some heuristic on the body type? Nagel-like timers?
-				// Based on 'n'? Only last chunk of this for loop, unless flow control
-				// tokens are low? For now, always:
+				// Most requests won't need this. Make this opt-in or
+				// opt-out?  Use some heuristic on the body type? Nagel-like
+				// timers?  Based on 'n'? Only last chunk of this for loop,
+				// unless flow control tokens are low? For now, always.
+				// If we change this, see comment below.
 				err = cc.bw.Flush()
 			}
 			cc.wmu.Unlock()
@@ -921,28 +918,33 @@ func (cs *clientStream) writeRequestBody(body io.Reader, bodyCloser io.Closer) (
 		}
 	}
 
+	if sentEnd {
+		// Already sent END_STREAM (which implies we have no
+		// trailers) and flushed, because currently all
+		// WriteData frames above get a flush. So we're done.
+		return nil
+	}
+
+	var trls []byte
+	if hasTrailers {
+		cc.mu.Lock()
+		defer cc.mu.Unlock()
+		trls = cc.encodeTrailers(req)
+	}
+
 	cc.wmu.Lock()
-	if !sentEnd {
-		var trls []byte
-		if hasTrailers {
-			cc.mu.Lock()
-			trls = cc.encodeTrailers(req)
-			cc.mu.Unlock()
-		}
+	defer cc.wmu.Unlock()
 
-		// Avoid forgetting to send an END_STREAM if the encoded
-		// trailers are 0 bytes. Both results produce and END_STREAM.
-		if len(trls) > 0 {
-			err = cc.writeHeaders(cs.ID, true, trls)
-		} else {
-			err = cc.fr.WriteData(cs.ID, true, nil)
-		}
+	// Two ways to send END_STREAM: either with trailers, or
+	// with an empty DATA frame.
+	if len(trls) > 0 {
+		err = cc.writeHeaders(cs.ID, true, trls)
+	} else {
+		err = cc.fr.WriteData(cs.ID, true, nil)
 	}
 	if ferr := cc.bw.Flush(); ferr != nil && err == nil {
 		err = ferr
 	}
-	cc.wmu.Unlock()
-
 	return err
 }
 
@@ -996,6 +998,22 @@ func (cc *ClientConn) encodeHeaders(req *http.Request, addGzipHeader bool, trail
 		host = req.URL.Host
 	}
 
+	var path string
+	if req.Method != "CONNECT" {
+		path = req.URL.RequestURI()
+		if !validPseudoPath(path) {
+			orig := path
+			path = strings.TrimPrefix(path, req.URL.Scheme+"://"+host)
+			if !validPseudoPath(path) {
+				if req.URL.Opaque != "" {
+					return nil, fmt.Errorf("invalid request :path %q from URL.Opaque = %q", orig, req.URL.Opaque)
+				} else {
+					return nil, fmt.Errorf("invalid request :path %q", orig)
+				}
+			}
+		}
+	}
+
 	// Check for any invalid headers and return an error before we
 	// potentially pollute our hpack state. (We want to be able to
 	// continue to reuse the hpack encoder for future requests)
@@ -1018,7 +1036,7 @@ func (cc *ClientConn) encodeHeaders(req *http.Request, addGzipHeader bool, trail
 	cc.writeHeader(":authority", host)
 	cc.writeHeader(":method", req.Method)
 	if req.Method != "CONNECT" {
-		cc.writeHeader(":path", req.URL.RequestURI())
+		cc.writeHeader(":path", path)
 		cc.writeHeader(":scheme", "https")
 	}
 	if trailers != "" {
@@ -1188,6 +1206,14 @@ func (e GoAwayError) Error() string {
 		e.LastStreamID, e.ErrCode, e.DebugData)
 }
 
+func isEOFOrNetReadError(err error) bool {
+	if err == io.EOF {
+		return true
+	}
+	ne, ok := err.(*net.OpError)
+	return ok && ne.Op == "read"
+}
+
 func (rl *clientConnReadLoop) cleanup() {
 	cc := rl.cc
 	defer cc.tconn.Close()
@@ -1199,16 +1225,14 @@ func (rl *clientConnReadLoop) cleanup() {
 	// gotten a response yet.
 	err := cc.readerErr
 	cc.mu.Lock()
-	if err == io.EOF {
-		if cc.goAway != nil {
-			err = GoAwayError{
-				LastStreamID: cc.goAway.LastStreamID,
-				ErrCode:      cc.goAway.ErrCode,
-				DebugData:    cc.goAwayDebug,
-			}
-		} else {
-			err = io.ErrUnexpectedEOF
+	if cc.goAway != nil && isEOFOrNetReadError(err) {
+		err = GoAwayError{
+			LastStreamID: cc.goAway.LastStreamID,
+			ErrCode:      cc.goAway.ErrCode,
+			DebugData:    cc.goAwayDebug,
 		}
+	} else if err == io.EOF {
+		err = io.ErrUnexpectedEOF
 	}
 	for _, cs := range rl.activeRes {
 		cs.bufPipe.CloseWithError(err)
@@ -1228,15 +1252,20 @@ func (rl *clientConnReadLoop) cleanup() {
 func (rl *clientConnReadLoop) run() error {
 	cc := rl.cc
 	rl.closeWhenIdle = cc.t.disableKeepAlives() || cc.singleUse
-	gotReply := false // ever saw a reply
+	gotReply := false // ever saw a HEADERS reply
+	gotSettings := false
 	for {
 		f, err := cc.fr.ReadFrame()
 		if err != nil {
-			cc.vlogf("Transport readFrame error: (%T) %v", err, err)
+			cc.vlogf("http2: Transport readFrame error on conn %p: (%T) %v", cc, err, err)
 		}
 		if se, ok := err.(StreamError); ok {
 			if cs := cc.streamByID(se.StreamID, true /*ended; remove it*/); cs != nil {
-				rl.endStreamError(cs, cc.fr.errDetail)
+				cs.cc.writeStreamReset(cs.ID, se.Code, err)
+				if se.Cause == nil {
+					se.Cause = cc.fr.errDetail
+				}
+				rl.endStreamError(cs, se)
 			}
 			continue
 		} else if err != nil {
@@ -1245,6 +1274,13 @@ func (rl *clientConnReadLoop) run() error {
 		if VerboseLogs {
 			cc.vlogf("http2: Transport received %s", summarizeFrame(f))
 		}
+		if !gotSettings {
+			if _, ok := f.(*SettingsFrame); !ok {
+				cc.logf("protocol error: received %T before a SETTINGS frame", f)
+				return ConnectionError(ErrCodeProtocol)
+			}
+			gotSettings = true
+		}
 		maybeIdle := false // whether frame might transition us to idle
 
 		switch f := f.(type) {
@@ -1273,6 +1309,9 @@ func (rl *clientConnReadLoop) run() error {
 			cc.logf("Transport: unhandled response frame type %T", f)
 		}
 		if err != nil {
+			if VerboseLogs {
+				cc.vlogf("http2: Transport conn %p received error from processing frame %v: %v", cc, summarizeFrame(f), err)
+			}
 			return err
 		}
 		if rl.closeWhenIdle && gotReply && maybeIdle && len(rl.activeRes) == 0 {
@@ -1522,10 +1561,27 @@ var errClosedResponseBody = errors.New("http2: response body closed")
 
 func (b transportResponseBody) Close() error {
 	cs := b.cs
-	if cs.bufPipe.Err() != io.EOF {
-		// TODO: write test for this
-		cs.cc.writeStreamReset(cs.ID, ErrCodeCancel, nil)
+	cc := cs.cc
+
+	serverSentStreamEnd := cs.bufPipe.Err() == io.EOF
+	unread := cs.bufPipe.Len()
+
+	if unread > 0 || !serverSentStreamEnd {
+		cc.mu.Lock()
+		cc.wmu.Lock()
+		if !serverSentStreamEnd {
+			cc.fr.WriteRSTStream(cs.ID, ErrCodeCancel)
+		}
+		// Return connection-level flow control.
+		if unread > 0 {
+			cc.inflow.add(int32(unread))
+			cc.fr.WriteWindowUpdate(0, uint32(unread))
+		}
+		cc.bw.Flush()
+		cc.wmu.Unlock()
+		cc.mu.Unlock()
 	}
+
 	cs.bufPipe.BreakWithError(errClosedResponseBody)
 	return nil
 }
@@ -1533,6 +1589,7 @@ func (b transportResponseBody) Close() error {
 func (rl *clientConnReadLoop) processData(f *DataFrame) error {
 	cc := rl.cc
 	cs := cc.streamByID(f.StreamID, f.StreamEnded())
+	data := f.Data()
 	if cs == nil {
 		cc.mu.Lock()
 		neverSent := cc.nextStreamID
@@ -1546,10 +1603,22 @@ func (rl *clientConnReadLoop) processData(f *DataFrame) error {
 		// TODO: be stricter here? only silently ignore things which
 		// we canceled, but not things which were closed normally
 		// by the peer? Tough without accumulating too much state.
+
+		// But at least return their flow control:
+		if f.Length > 0 {
+			cc.mu.Lock()
+			cc.inflow.add(int32(f.Length))
+			cc.mu.Unlock()
+
+			cc.wmu.Lock()
+			cc.fr.WriteWindowUpdate(0, uint32(f.Length))
+			cc.bw.Flush()
+			cc.wmu.Unlock()
+		}
 		return nil
 	}
-	if data := f.Data(); len(data) > 0 {
-		if cs.bufPipe.b == nil {
+	if f.Length > 0 {
+		if len(data) > 0 && cs.bufPipe.b == nil {
 			// Data frame after it's already closed?
 			cc.logf("http2: Transport received DATA frame for closed stream; closing connection")
 			return ConnectionError(ErrCodeProtocol)
@@ -1557,17 +1626,30 @@ func (rl *clientConnReadLoop) processData(f *DataFrame) error {
 
 		// Check connection-level flow control.
 		cc.mu.Lock()
-		if cs.inflow.available() >= int32(len(data)) {
-			cs.inflow.take(int32(len(data)))
+		if cs.inflow.available() >= int32(f.Length) {
+			cs.inflow.take(int32(f.Length))
 		} else {
 			cc.mu.Unlock()
 			return ConnectionError(ErrCodeFlowControl)
 		}
+		// Return any padded flow control now, since we won't
+		// refund it later on body reads.
+		if pad := int32(f.Length) - int32(len(data)); pad > 0 {
+			cs.inflow.add(pad)
+			cc.inflow.add(pad)
+			cc.wmu.Lock()
+			cc.fr.WriteWindowUpdate(0, uint32(pad))
+			cc.fr.WriteWindowUpdate(cs.ID, uint32(pad))
+			cc.bw.Flush()
+			cc.wmu.Unlock()
+		}
 		cc.mu.Unlock()
 
-		if _, err := cs.bufPipe.Write(data); err != nil {
-			rl.endStreamError(cs, err)
-			return err
+		if len(data) > 0 {
+			if _, err := cs.bufPipe.Write(data); err != nil {
+				rl.endStreamError(cs, err)
+				return err
+			}
 		}
 	}
 
@@ -1596,6 +1678,11 @@ func (rl *clientConnReadLoop) endStreamError(cs *clientStream, err error) {
 	if isConnectionCloseRequest(cs.req) {
 		rl.closeWhenIdle = true
 	}
+
+	select {
+	case cs.resc <- resAndError{err: err}:
+	default:
+	}
 }
 
 func (cs *clientStream) copyTrailers() {
@@ -1623,18 +1710,39 @@ func (rl *clientConnReadLoop) processSettings(f *SettingsFrame) error {
 	cc := rl.cc
 	cc.mu.Lock()
 	defer cc.mu.Unlock()
-	return f.ForeachSetting(func(s Setting) error {
+
+	if f.IsAck() {
+		if cc.wantSettingsAck {
+			cc.wantSettingsAck = false
+			return nil
+		}
+		return ConnectionError(ErrCodeProtocol)
+	}
+
+	err := f.ForeachSetting(func(s Setting) error {
 		switch s.ID {
 		case SettingMaxFrameSize:
 			cc.maxFrameSize = s.Val
 		case SettingMaxConcurrentStreams:
 			cc.maxConcurrentStreams = s.Val
 		case SettingInitialWindowSize:
-			// TODO: error if this is too large.
+			// Values above the maximum flow-control
+			// window size of 2^31-1 MUST be treated as a
+			// connection error (Section 5.4.1) of type
+			// FLOW_CONTROL_ERROR.
+			if s.Val > math.MaxInt32 {
+				return ConnectionError(ErrCodeFlowControl)
+			}
 
-			// TODO: adjust flow control of still-open
+			// Adjust flow control of currently-open
 			// frames by the difference of the old initial
 			// window size and this one.
+			delta := int32(s.Val) - int32(cc.initialWindowSize)
+			for _, cs := range cc.streams {
+				cs.flow.add(delta)
+			}
+			cc.cond.Broadcast()
+
 			cc.initialWindowSize = s.Val
 		default:
 			// TODO(bradfitz): handle more settings? SETTINGS_HEADER_TABLE_SIZE probably.
@@ -1642,6 +1750,16 @@ func (rl *clientConnReadLoop) processSettings(f *SettingsFrame) error {
 		}
 		return nil
 	})
+	if err != nil {
+		return err
+	}
+
+	cc.wmu.Lock()
+	defer cc.wmu.Unlock()
+
+	cc.fr.WriteSettingsAck()
+	cc.bw.Flush()
+	return cc.werr
 }
 
 func (rl *clientConnReadLoop) processWindowUpdate(f *WindowUpdateFrame) error {
@@ -1678,7 +1796,7 @@ func (rl *clientConnReadLoop) processResetStream(f *RSTStreamFrame) error {
 		// which closes this, so there
 		// isn't a race.
 	default:
-		err := StreamError{cs.ID, f.ErrCode}
+		err := streamError(cs.ID, f.ErrCode)
 		cs.resetErr = err
 		close(cs.peerReset)
 		cs.bufPipe.CloseWithError(err)
@@ -1715,8 +1833,10 @@ func (rl *clientConnReadLoop) processPushPromise(f *PushPromiseFrame) error {
 }
 
 func (cc *ClientConn) writeStreamReset(streamID uint32, code ErrCode, err error) {
-	// TODO: do something with err? send it as a debug frame to the peer?
-	// But that's only in GOAWAY. Invent a new frame type? Is there one already?
+	// TODO: map err to more interesting error codes, once the
+	// HTTP community comes up with some. But currently for
+	// RST_STREAM there's no equivalent to GOAWAY frame's debug
+	// data, and the error codes are all pretty vague ("cancel").
 	cc.wmu.Lock()
 	cc.fr.WriteRSTStream(streamID, code)
 	cc.bw.Flush()