Fix GCS

Signed-off-by: Olivier Gambier <olivier@docker.com>

vendor/golang.org/x/net/http2/write.go

@@ -0,0 +1,262 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http2
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+	"net/http"
+	"time"
+
+	"golang.org/x/net/http2/hpack"
+)
+
+// writeFramer is implemented by any type that is used to write frames.
+type writeFramer interface {
+	writeFrame(writeContext) error
+}
+
+// writeContext is the interface needed by the various frame writer
+// types below. All the writeFrame methods below are scheduled via the
+// frame writing scheduler (see writeScheduler in writesched.go).
+//
+// This interface is implemented by *serverConn.
+//
+// TODO: decide whether to a) use this in the client code (which didn't
+// end up using this yet, because it has a simpler design, not
+// currently implementing priorities), or b) delete this and
+// make the server code a bit more concrete.
+type writeContext interface {
+	Framer() *Framer
+	Flush() error
+	CloseConn() error
+	// HeaderEncoder returns an HPACK encoder that writes to the
+	// returned buffer.
+	HeaderEncoder() (*hpack.Encoder, *bytes.Buffer)
+}
+
+// endsStream reports whether the given frame writer w will locally
+// close the stream.
+func endsStream(w writeFramer) bool {
+	switch v := w.(type) {
+	case *writeData:
+		return v.endStream
+	case *writeResHeaders:
+		return v.endStream
+	case nil:
+		// This can only happen if the caller reuses w after it's
+		// been intentionally nil'ed out to prevent use. Keep this
+		// here to catch future refactoring breaking it.
+		panic("endsStream called on nil writeFramer")
+	}
+	return false
+}
+
+type flushFrameWriter struct{}
+
+func (flushFrameWriter) writeFrame(ctx writeContext) error {
+	return ctx.Flush()
+}
+
+type writeSettings []Setting
+
+func (s writeSettings) writeFrame(ctx writeContext) error {
+	return ctx.Framer().WriteSettings([]Setting(s)...)
+}
+
+type writeGoAway struct {
+	maxStreamID uint32
+	code        ErrCode
+}
+
+func (p *writeGoAway) writeFrame(ctx writeContext) error {
+	err := ctx.Framer().WriteGoAway(p.maxStreamID, p.code, nil)
+	if p.code != 0 {
+		ctx.Flush() // ignore error: we're hanging up on them anyway
+		time.Sleep(50 * time.Millisecond)
+		ctx.CloseConn()
+	}
+	return err
+}
+
+type writeData struct {
+	streamID  uint32
+	p         []byte
+	endStream bool
+}
+
+func (w *writeData) String() string {
+	return fmt.Sprintf("writeData(stream=%d, p=%d, endStream=%v)", w.streamID, len(w.p), w.endStream)
+}
+
+func (w *writeData) writeFrame(ctx writeContext) error {
+	return ctx.Framer().WriteData(w.streamID, w.endStream, w.p)
+}
+
+// handlerPanicRST is the message sent from handler goroutines when
+// the handler panics.
+type handlerPanicRST struct {
+	StreamID uint32
+}
+
+func (hp handlerPanicRST) writeFrame(ctx writeContext) error {
+	return ctx.Framer().WriteRSTStream(hp.StreamID, ErrCodeInternal)
+}
+
+func (se StreamError) writeFrame(ctx writeContext) error {
+	return ctx.Framer().WriteRSTStream(se.StreamID, se.Code)
+}
+
+type writePingAck struct{ pf *PingFrame }
+
+func (w writePingAck) writeFrame(ctx writeContext) error {
+	return ctx.Framer().WritePing(true, w.pf.Data)
+}
+
+type writeSettingsAck struct{}
+
+func (writeSettingsAck) writeFrame(ctx writeContext) error {
+	return ctx.Framer().WriteSettingsAck()
+}
+
+// writeResHeaders is a request to write a HEADERS and 0+ CONTINUATION frames
+// for HTTP response headers or trailers from a server handler.
+type writeResHeaders struct {
+	streamID    uint32
+	httpResCode int         // 0 means no ":status" line
+	h           http.Header // may be nil
+	trailers    []string    // if non-nil, which keys of h to write. nil means all.
+	endStream   bool
+
+	date          string
+	contentType   string
+	contentLength string
+}
+
+func encKV(enc *hpack.Encoder, k, v string) {
+	if VerboseLogs {
+		log.Printf("http2: server encoding header %q = %q", k, v)
+	}
+	enc.WriteField(hpack.HeaderField{Name: k, Value: v})
+}
+
+func (w *writeResHeaders) writeFrame(ctx writeContext) error {
+	enc, buf := ctx.HeaderEncoder()
+	buf.Reset()
+
+	if w.httpResCode != 0 {
+		encKV(enc, ":status", httpCodeString(w.httpResCode))
+	}
+
+	encodeHeaders(enc, w.h, w.trailers)
+
+	if w.contentType != "" {
+		encKV(enc, "content-type", w.contentType)
+	}
+	if w.contentLength != "" {
+		encKV(enc, "content-length", w.contentLength)
+	}
+	if w.date != "" {
+		encKV(enc, "date", w.date)
+	}
+
+	headerBlock := buf.Bytes()
+	if len(headerBlock) == 0 && w.trailers == nil {
+		panic("unexpected empty hpack")
+	}
+
+	// For now we're lazy and just pick the minimum MAX_FRAME_SIZE
+	// that all peers must support (16KB). Later we could care
+	// more and send larger frames if the peer advertised it, but
+	// there's little point. Most headers are small anyway (so we
+	// generally won't have CONTINUATION frames), and extra frames
+	// only waste 9 bytes anyway.
+	const maxFrameSize = 16384
+
+	first := true
+	for len(headerBlock) > 0 {
+		frag := headerBlock
+		if len(frag) > maxFrameSize {
+			frag = frag[:maxFrameSize]
+		}
+		headerBlock = headerBlock[len(frag):]
+		endHeaders := len(headerBlock) == 0
+		var err error
+		if first {
+			first = false
+			err = ctx.Framer().WriteHeaders(HeadersFrameParam{
+				StreamID:      w.streamID,
+				BlockFragment: frag,
+				EndStream:     w.endStream,
+				EndHeaders:    endHeaders,
+			})
+		} else {
+			err = ctx.Framer().WriteContinuation(w.streamID, endHeaders, frag)
+		}
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+type write100ContinueHeadersFrame struct {
+	streamID uint32
+}
+
+func (w write100ContinueHeadersFrame) writeFrame(ctx writeContext) error {
+	enc, buf := ctx.HeaderEncoder()
+	buf.Reset()
+	encKV(enc, ":status", "100")
+	return ctx.Framer().WriteHeaders(HeadersFrameParam{
+		StreamID:      w.streamID,
+		BlockFragment: buf.Bytes(),
+		EndStream:     false,
+		EndHeaders:    true,
+	})
+}
+
+type writeWindowUpdate struct {
+	streamID uint32 // or 0 for conn-level
+	n        uint32
+}
+
+func (wu writeWindowUpdate) writeFrame(ctx writeContext) error {
+	return ctx.Framer().WriteWindowUpdate(wu.streamID, wu.n)
+}
+
+func encodeHeaders(enc *hpack.Encoder, h http.Header, keys []string) {
+	if keys == nil {
+		sorter := sorterPool.Get().(*sorter)
+		// Using defer here, since the returned keys from the
+		// sorter.Keys method is only valid until the sorter
+		// is returned:
+		defer sorterPool.Put(sorter)
+		keys = sorter.Keys(h)
+	}
+	for _, k := range keys {
+		vv := h[k]
+		k = lowerHeader(k)
+		if !validHeaderFieldName(k) {
+			// TODO: return an error? golang.org/issue/14048
+			// For now just omit it.
+			continue
+		}
+		isTE := k == "transfer-encoding"
+		for _, v := range vv {
+			if !validHeaderFieldValue(v) {
+				// TODO: return an error? golang.org/issue/14048
+				// For now just omit it.
+				continue
+			}
+			// TODO: more of "8.1.2.2 Connection-Specific Header Fields"
+			if isTE && v != "trailers" {
+				continue
+			}
+			encKV(enc, k, v)
+		}
+	}
+}