Updates hashicorp/yamux.

vendor/github.com/hashicorp/yamux/.gitignore

@@ -1,23 +0,0 @@
-# Compiled Object files, Static and Dynamic libs (Shared Objects)
-*.o
-*.a
-*.so
-
-# Folders
-_obj
-_test
-
-# Architecture specific extensions/prefixes
-*.[568vq]
-[568vq].out
-
-*.cgo1.go
-*.cgo2.c
-_cgo_defun.c
-_cgo_gotypes.go
-_cgo_export.*
-
-_testmain.go
-
-*.exe
-*.test

vendor/github.com/hashicorp/yamux/session.go

@@ -46,8 +46,11 @@ type Session struct {
 	pingID   uint32
 	pingLock sync.Mutex
 
-	// streams maps a stream id to a stream
+	// streams maps a stream id to a stream, and inflight has an entry
+	// for any outgoing stream that has not yet been established. Both are
+	// protected by streamLock.
 	streams    map[uint32]*Stream
+	inflight   map[uint32]struct{}
 	streamLock sync.Mutex
 
 	// synCh acts like a semaphore. It is sized to the AcceptBacklog which
@@ -90,6 +93,7 @@ func newSession(config *Config, conn io.ReadWriteCloser, client bool) *Session {
 		bufRead:    bufio.NewReader(conn),
 		pings:      make(map[uint32]chan struct{}),
 		streams:    make(map[uint32]*Stream),
+		inflight:   make(map[uint32]struct{}),
 		synCh:      make(chan struct{}, config.AcceptBacklog),
 		acceptCh:   make(chan *Stream, config.AcceptBacklog),
 		sendCh:     make(chan sendReady, 64),
@@ -153,7 +157,7 @@ func (s *Session) OpenStream() (*Stream, error) {
 	}
 
 GET_ID:
-	// Get and ID, and check for stream exhaustion
+	// Get an ID, and check for stream exhaustion
 	id := atomic.LoadUint32(&s.nextStreamID)
 	if id >= math.MaxUint32-1 {
 		return nil, ErrStreamsExhausted
@@ -166,10 +170,16 @@ GET_ID:
 	stream := newStream(s, id, streamInit)
 	s.streamLock.Lock()
 	s.streams[id] = stream
+	s.inflight[id] = struct{}{}
 	s.streamLock.Unlock()
 
 	// Send the window update to create
 	if err := stream.sendWindowUpdate(); err != nil {
+		select {
+		case <-s.synCh:
+		default:
+			s.logger.Printf("[ERR] yamux: aborted stream open without inflight syn semaphore")
+		}
 		return nil, err
 	}
 	return stream, nil
@@ -580,19 +590,34 @@ func (s *Session) incomingStream(id uint32) error {
 }
 
 // closeStream is used to close a stream once both sides have
-// issued a close.
+// issued a close. If there was an in-flight SYN and the stream
+// was not yet established, then this will give the credit back.
 func (s *Session) closeStream(id uint32) {
 	s.streamLock.Lock()
+	if _, ok := s.inflight[id]; ok {
+		select {
+		case <-s.synCh:
+		default:
+			s.logger.Printf("[ERR] yamux: SYN tracking out of sync")
+		}
+	}
 	delete(s.streams, id)
 	s.streamLock.Unlock()
 }
 
 // establishStream is used to mark a stream that was in the
 // SYN Sent state as established.
-func (s *Session) establishStream() {
+func (s *Session) establishStream(id uint32) {
+	s.streamLock.Lock()
+	if _, ok := s.inflight[id]; ok {
+		delete(s.inflight, id)
+	} else {
+		s.logger.Printf("[ERR] yamux: established stream without inflight SYN (no tracking entry)")
+	}
 	select {
 	case <-s.synCh:
 	default:
-		panic("established stream without inflight syn")
+		s.logger.Printf("[ERR] yamux: established stream without inflight SYN (didn't have semaphore)")
 	}
+	s.streamLock.Unlock()
 }

vendor/github.com/hashicorp/yamux/spec.md

@@ -22,7 +22,7 @@ Each field is described below:
 
 ## Version Field
 
-The version field is used for future backwards compatibily. At the
+The version field is used for future backward compatibility. At the
 current time, the field is always set to 0, to indicate the initial
 version.
 
@@ -96,7 +96,7 @@ Because we are relying on the reliable stream underneath, a connection
 can begin sending data once the SYN flag is sent. The corresponding
 ACK does not need to be received. This is particularly well suited
 for an RPC system where a client wants to open a stream and immediately
-fire a request without wiating for the RTT of the ACK.
+fire a request without waiting for the RTT of the ACK.
 
 This does introduce the possibility of a connection being rejected
 after data has been sent already. This is a slight semantic difference
@@ -138,4 +138,3 @@ provide an error code:
 * 0x0 Normal termination
 * 0x1 Protocol error
 * 0x2 Internal error
-

vendor/github.com/hashicorp/yamux/stream.go

@@ -91,10 +91,13 @@ START:
 	case streamRemoteClose:
 		fallthrough
 	case streamClosed:
+		s.recvLock.Lock()
 		if s.recvBuf == nil || s.recvBuf.Len() == 0 {
+			s.recvLock.Unlock()
 			s.stateLock.Unlock()
 			return 0, io.EOF
 		}
+		s.recvLock.Unlock()
 	case streamReset:
 		s.stateLock.Unlock()
 		return 0, ErrConnectionReset
@@ -118,12 +121,17 @@ START:
 
 WAIT:
 	var timeout <-chan time.Time
+	var timer *time.Timer
 	if !s.readDeadline.IsZero() {
 		delay := s.readDeadline.Sub(time.Now())
-		timeout = time.After(delay)
+		timer = time.NewTimer(delay)
+		timeout = timer.C
 	}
 	select {
 	case <-s.recvNotifyCh:
+		if timer != nil {
+			timer.Stop()
+		}
 		goto START
 	case <-timeout:
 		return 0, ErrTimeout
@@ -327,7 +335,7 @@ func (s *Stream) processFlags(flags uint16) error {
 		if s.state == streamSYNSent {
 			s.state = streamEstablished
 		}
-		s.session.establishStream()
+		s.session.establishStream(s.id)
 	}
 	if flags&flagFIN == flagFIN {
 		switch s.state {
@@ -348,9 +356,6 @@ func (s *Stream) processFlags(flags uint16) error {
 		}
 	}
 	if flags&flagRST == flagRST {
-		if s.state == streamSYNSent {
-			s.session.establishStream()
-		}
 		s.state = streamReset
 		closeStream = true
 		s.notifyWaiting()

vendor/vendor.json

@@ -394,8 +394,10 @@
 			"revisionTime": "2016-08-09T01:42:04Z"
 		},
 		{
+			"checksumSHA1": "ZhK6IO2XN81Y+3RAjTcVm1Ic7oU=",
 			"path": "github.com/hashicorp/yamux",
-			"revision": "df949784da9ed028ee76df44652e42d37a09d7e4"
+			"revision": "d1caa6c97c9fc1cc9e83bbe34d0603f9ff0ce8bd",
+			"revisionTime": "2016-07-20T23:31:40Z"
 		},
 		{
 			"path": "github.com/inconshreveable/muxado",