diff options
Diffstat (limited to 'vendor/golang.org/x/net/http2/transport.go')
| -rw-r--r-- | vendor/golang.org/x/net/http2/transport.go | 2453 |
1 files changed, 0 insertions, 2453 deletions
diff --git a/vendor/golang.org/x/net/http2/transport.go b/vendor/golang.org/x/net/http2/transport.go deleted file mode 100644 index 9d1f2fa..0000000 --- a/vendor/golang.org/x/net/http2/transport.go +++ /dev/null @@ -1,2453 +0,0 @@ -// Copyright 2015 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. - -// Transport code. - -package http2 - -import ( - "bufio" - "bytes" - "compress/gzip" - "crypto/rand" - "crypto/tls" - "errors" - "fmt" - "io" - "io/ioutil" - "log" - "math" - mathrand "math/rand" - "net" - "net/http" - "net/textproto" - "sort" - "strconv" - "strings" - "sync" - "time" - - "golang.org/x/net/http/httpguts" - "golang.org/x/net/http2/hpack" - "golang.org/x/net/idna" -) - -const ( - // transportDefaultConnFlow is how many connection-level flow control - // tokens we give the server at start-up, past the default 64k. - transportDefaultConnFlow = 1 << 30 - - // transportDefaultStreamFlow is how many stream-level flow - // control tokens we announce to the peer, and how many bytes - // we buffer per stream. - transportDefaultStreamFlow = 4 << 20 - - // transportDefaultStreamMinRefresh is the minimum number of bytes we'll send - // a stream-level WINDOW_UPDATE for at a time. - transportDefaultStreamMinRefresh = 4 << 10 - - defaultUserAgent = "Go-http-client/2.0" -) - -// Transport is an HTTP/2 Transport. -// -// A Transport internally caches connections to servers. It is safe -// for concurrent use by multiple goroutines. -type Transport struct { - // DialTLS specifies an optional dial function for creating - // TLS connections for requests. - // - // If DialTLS is nil, tls.Dial is used. - // - // If the returned net.Conn has a ConnectionState method like tls.Conn, - // it will be used to set http.Response.TLS. - DialTLS func(network, addr string, cfg *tls.Config) (net.Conn, error) - - // TLSClientConfig specifies the TLS configuration to use with - // tls.Client. If nil, the default configuration is used. - TLSClientConfig *tls.Config - - // ConnPool optionally specifies an alternate connection pool to use. - // If nil, the default is used. - ConnPool ClientConnPool - - // DisableCompression, if true, prevents the Transport from - // requesting compression with an "Accept-Encoding: gzip" - // request header when the Request contains no existing - // Accept-Encoding value. If the Transport requests gzip on - // its own and gets a gzipped response, it's transparently - // decoded in the Response.Body. However, if the user - // explicitly requested gzip it is not automatically - // uncompressed. - DisableCompression bool - - // AllowHTTP, if true, permits HTTP/2 requests using the insecure, - // plain-text "http" scheme. Note that this does not enable h2c support. - AllowHTTP bool - - // MaxHeaderListSize is the http2 SETTINGS_MAX_HEADER_LIST_SIZE to - // send in the initial settings frame. It is how many bytes - // of response headers are allowed. Unlike the http2 spec, zero here - // means to use a default limit (currently 10MB). If you actually - // want to advertise an ulimited value to the peer, Transport - // interprets the highest possible value here (0xffffffff or 1<<32-1) - // to mean no limit. - MaxHeaderListSize uint32 - - // t1, if non-nil, is the standard library Transport using - // this transport. Its settings are used (but not its - // RoundTrip method, etc). - t1 *http.Transport - - connPoolOnce sync.Once - connPoolOrDef ClientConnPool // non-nil version of ConnPool -} - -func (t *Transport) maxHeaderListSize() uint32 { - if t.MaxHeaderListSize == 0 { - return 10 << 20 - } - if t.MaxHeaderListSize == 0xffffffff { - return 0 - } - return t.MaxHeaderListSize -} - -func (t *Transport) disableCompression() bool { - return t.DisableCompression || (t.t1 != nil && t.t1.DisableCompression) -} - -var errTransportVersion = errors.New("http2: ConfigureTransport is only supported starting at Go 1.6") - -// ConfigureTransport configures a net/http HTTP/1 Transport to use HTTP/2. -// It requires Go 1.6 or later and returns an error if the net/http package is too old -// or if t1 has already been HTTP/2-enabled. -func ConfigureTransport(t1 *http.Transport) error { - _, err := configureTransport(t1) // in configure_transport.go (go1.6) or not_go16.go - return err -} - -func (t *Transport) connPool() ClientConnPool { - t.connPoolOnce.Do(t.initConnPool) - return t.connPoolOrDef -} - -func (t *Transport) initConnPool() { - if t.ConnPool != nil { - t.connPoolOrDef = t.ConnPool - } else { - t.connPoolOrDef = &clientConnPool{t: t} - } -} - -// ClientConn is the state of a single HTTP/2 client connection to an -// HTTP/2 server. -type ClientConn struct { - t *Transport - tconn net.Conn // usually *tls.Conn, except specialized impls - tlsState *tls.ConnectionState // nil only for specialized impls - singleUse bool // whether being used for a single http.Request - - // readLoop goroutine fields: - readerDone chan struct{} // closed on error - readerErr error // set before readerDone is closed - - idleTimeout time.Duration // or 0 for never - idleTimer *time.Timer - - 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 - closing bool - 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 - pendingRequests int // requests blocked and waiting to be sent because len(streams) == maxConcurrentStreams - pings map[[8]byte]chan struct{} // in flight ping data to notification channel - bw *bufio.Writer - br *bufio.Reader - fr *Framer - lastActive time.Time - // Settings from peer: (also guarded by mu) - maxFrameSize uint32 - maxConcurrentStreams uint32 - peerMaxHeaderListSize uint64 - initialWindowSize uint32 - - 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 -} - -// clientStream is the state for a single HTTP/2 stream. One of these -// is created for each Transport.RoundTrip call. -type clientStream struct { - cc *ClientConn - req *http.Request - trace *clientTrace // or nil - ID uint32 - resc chan resAndError - bufPipe pipe // buffered pipe with the flow-controlled response payload - startedWrite bool // started request body write; guarded by cc.mu - requestedGzip bool - on100 func() // optional code to run if get a 100 continue response - - flow flow // guarded by cc.mu - inflow flow // guarded by cc.mu - bytesRemain int64 // -1 means unknown; owned by transportResponseBody.Read - readErr error // sticky read error; owned by transportResponseBody.Read - stopReqBody error // if non-nil, stop writing req body; guarded by cc.mu - didReset bool // whether we sent a RST_STREAM to the server; guarded by cc.mu - - peerReset chan struct{} // closed on peer reset - resetErr error // populated before peerReset is closed - - done chan struct{} // closed when stream remove from cc.streams map; close calls guarded by cc.mu - - // owned by clientConnReadLoop: - firstByte bool // got the first response byte - pastHeaders bool // got first MetaHeadersFrame (actual headers) - pastTrailers bool // got optional second MetaHeadersFrame (trailers) - num1xx uint8 // number of 1xx responses seen - - trailer http.Header // accumulated trailers - resTrailer *http.Header // client's Response.Trailer -} - -// awaitRequestCancel waits for the user to cancel a request or for the done -// channel to be signaled. A non-nil error is returned only if the request was -// canceled. -func awaitRequestCancel(req *http.Request, done <-chan struct{}) error { - ctx := reqContext(req) - if req.Cancel == nil && ctx.Done() == nil { - return nil - } - select { - case <-req.Cancel: - return errRequestCanceled - case <-ctx.Done(): - return ctx.Err() - case <-done: - return nil - } -} - -var got1xxFuncForTests func(int, textproto.MIMEHeader) error - -// get1xxTraceFunc returns the value of request's httptrace.ClientTrace.Got1xxResponse func, -// if any. It returns nil if not set or if the Go version is too old. -func (cs *clientStream) get1xxTraceFunc() func(int, textproto.MIMEHeader) error { - if fn := got1xxFuncForTests; fn != nil { - return fn - } - return traceGot1xxResponseFunc(cs.trace) -} - -// awaitRequestCancel waits for the user to cancel a request, its context to -// expire, or for the request to be done (any way it might be removed from the -// cc.streams map: peer reset, successful completion, TCP connection breakage, -// etc). If the request is canceled, then cs will be canceled and closed. -func (cs *clientStream) awaitRequestCancel(req *http.Request) { - if err := awaitRequestCancel(req, cs.done); err != nil { - cs.cancelStream() - cs.bufPipe.CloseWithError(err) - } -} - -func (cs *clientStream) cancelStream() { - cc := cs.cc - cc.mu.Lock() - didReset := cs.didReset - cs.didReset = true - cc.mu.Unlock() - - if !didReset { - cc.writeStreamReset(cs.ID, ErrCodeCancel, nil) - cc.forgetStreamID(cs.ID) - } -} - -// checkResetOrDone reports any error sent in a RST_STREAM frame by the -// server, or errStreamClosed if the stream is complete. -func (cs *clientStream) checkResetOrDone() error { - select { - case <-cs.peerReset: - return cs.resetErr - case <-cs.done: - return errStreamClosed - default: - return nil - } -} - -func (cs *clientStream) getStartedWrite() bool { - cc := cs.cc - cc.mu.Lock() - defer cc.mu.Unlock() - return cs.startedWrite -} - -func (cs *clientStream) abortRequestBodyWrite(err error) { - if err == nil { - panic("nil error") - } - cc := cs.cc - cc.mu.Lock() - cs.stopReqBody = err - cc.cond.Broadcast() - cc.mu.Unlock() -} - -type stickyErrWriter struct { - w io.Writer - err *error -} - -func (sew stickyErrWriter) Write(p []byte) (n int, err error) { - if *sew.err != nil { - return 0, *sew.err - } - n, err = sew.w.Write(p) - *sew.err = err - return -} - -// noCachedConnError is the concrete type of ErrNoCachedConn, which -// needs to be detected by net/http regardless of whether it's its -// bundled version (in h2_bundle.go with a rewritten type name) or -// from a user's x/net/http2. As such, as it has a unique method name -// (IsHTTP2NoCachedConnError) that net/http sniffs for via func -// isNoCachedConnError. -type noCachedConnError struct{} - -func (noCachedConnError) IsHTTP2NoCachedConnError() {} -func (noCachedConnError) Error() string { return "http2: no cached connection was available" } - -// isNoCachedConnError reports whether err is of type noCachedConnError -// or its equivalent renamed type in net/http2's h2_bundle.go. Both types -// may coexist in the same running program. -func isNoCachedConnError(err error) bool { - _, ok := err.(interface{ IsHTTP2NoCachedConnError() }) - return ok -} - -var ErrNoCachedConn error = noCachedConnError{} - -// RoundTripOpt are options for the Transport.RoundTripOpt method. -type RoundTripOpt struct { - // OnlyCachedConn controls whether RoundTripOpt may - // create a new TCP connection. If set true and - // no cached connection is available, RoundTripOpt - // will return ErrNoCachedConn. - OnlyCachedConn bool -} - -func (t *Transport) RoundTrip(req *http.Request) (*http.Response, error) { - return t.RoundTripOpt(req, RoundTripOpt{}) -} - -// authorityAddr returns a given authority (a host/IP, or host:port / ip:port) -// and returns a host:port. The port 443 is added if needed. -func authorityAddr(scheme string, authority string) (addr string) { - host, port, err := net.SplitHostPort(authority) - if err != nil { // authority didn't have a port - port = "443" - if scheme == "http" { - port = "80" - } - host = authority - } - if a, err := idna.ToASCII(host); err == nil { - host = a - } - // IPv6 address literal, without a port: - if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") { - return host + ":" + port - } - return net.JoinHostPort(host, port) -} - -// RoundTripOpt is like RoundTrip, but takes options. -func (t *Transport) RoundTripOpt(req *http.Request, opt RoundTripOpt) (*http.Response, error) { - if !(req.URL.Scheme == "https" || (req.URL.Scheme == "http" && t.AllowHTTP)) { - return nil, errors.New("http2: unsupported scheme") - } - - addr := authorityAddr(req.URL.Scheme, req.URL.Host) - for retry := 0; ; retry++ { - cc, err := t.connPool().GetClientConn(req, addr) - if err != nil { - t.vlogf("http2: Transport failed to get client conn for %s: %v", addr, err) - return nil, err - } - traceGotConn(req, cc) - res, gotErrAfterReqBodyWrite, err := cc.roundTrip(req) - if err != nil && retry <= 6 { - if req, err = shouldRetryRequest(req, err, gotErrAfterReqBodyWrite); err == nil { - // After the first retry, do exponential backoff with 10% jitter. - if retry == 0 { - continue - } - backoff := float64(uint(1) << (uint(retry) - 1)) - backoff += backoff * (0.1 * mathrand.Float64()) - select { - case <-time.After(time.Second * time.Duration(backoff)): - continue - case <-reqContext(req).Done(): - return nil, reqContext(req).Err() - } - } - } - if err != nil { - t.vlogf("RoundTrip failure: %v", err) - return nil, err - } - return res, nil - } -} - -// CloseIdleConnections closes any connections which were previously -// connected from previous requests but are now sitting idle. -// It does not interrupt any connections currently in use. -func (t *Transport) CloseIdleConnections() { - if cp, ok := t.connPool().(clientConnPoolIdleCloser); ok { - cp.closeIdleConnections() - } -} - -var ( - errClientConnClosed = errors.New("http2: client conn is closed") - errClientConnUnusable = errors.New("http2: client conn not usable") - errClientConnGotGoAway = errors.New("http2: Transport received Server's graceful shutdown GOAWAY") -) - -// shouldRetryRequest is called by RoundTrip when a request fails to get -// response headers. It is always called with a non-nil error. -// It returns either a request to retry (either the same request, or a -// modified clone), or an error if the request can't be replayed. -func shouldRetryRequest(req *http.Request, err error, afterBodyWrite bool) (*http.Request, error) { - if !canRetryError(err) { - return nil, err - } - // If the Body is nil (or http.NoBody), it's safe to reuse - // this request and its Body. - if req.Body == nil || reqBodyIsNoBody(req.Body) { - return req, nil - } - - // If the request body can be reset back to its original - // state via the optional req.GetBody, do that. - getBody := reqGetBody(req) // Go 1.8: getBody = req.GetBody - if getBody != nil { - // TODO: consider a req.Body.Close here? or audit that all caller paths do? - body, err := getBody() - if err != nil { - return nil, err - } - newReq := *req - newReq.Body = body - return &newReq, nil - } - - // The Request.Body can't reset back to the beginning, but we - // don't seem to have started to read from it yet, so reuse - // the request directly. The "afterBodyWrite" means the - // bodyWrite process has started, which becomes true before - // the first Read. - if !afterBodyWrite { - return req, nil - } - - return nil, fmt.Errorf("http2: Transport: cannot retry err [%v] after Request.Body was written; define Request.GetBody to avoid this error", err) -} - -func canRetryError(err error) bool { - if err == errClientConnUnusable || err == errClientConnGotGoAway { - return true - } - if se, ok := err.(StreamError); ok { - return se.Code == ErrCodeRefusedStream - } - return false -} - -func (t *Transport) dialClientConn(addr string, singleUse bool) (*ClientConn, error) { - host, _, err := net.SplitHostPort(addr) - if err != nil { - return nil, err - } - tconn, err := t.dialTLS()("tcp", addr, t.newTLSConfig(host)) - if err != nil { - return nil, err - } - return t.newClientConn(tconn, singleUse) -} - -func (t *Transport) newTLSConfig(host string) *tls.Config { - cfg := new(tls.Config) - if t.TLSClientConfig != nil { - *cfg = *cloneTLSConfig(t.TLSClientConfig) - } - if !strSliceContains(cfg.NextProtos, NextProtoTLS) { - cfg.NextProtos = append([]string{NextProtoTLS}, cfg.NextProtos...) - } - if cfg.ServerName == "" { - cfg.ServerName = host - } - return cfg -} - -func (t *Transport) dialTLS() func(string, string, *tls.Config) (net.Conn, error) { - if t.DialTLS != nil { - return t.DialTLS - } - return t.dialTLSDefault -} - -func (t *Transport) dialTLSDefault(network, addr string, cfg *tls.Config) (net.Conn, error) { - cn, err := tls.Dial(network, addr, cfg) - if err != nil { - return nil, err - } - if err := cn.Handshake(); err != nil { - return nil, err - } - if !cfg.InsecureSkipVerify { - if err := cn.VerifyHostname(cfg.ServerName); err != nil { - return nil, err - } - } - state := cn.ConnectionState() - if p := state.NegotiatedProtocol; p != NextProtoTLS { - return nil, fmt.Errorf("http2: unexpected ALPN protocol %q; want %q", p, NextProtoTLS) - } - if !state.NegotiatedProtocolIsMutual { - return nil, errors.New("http2: could not negotiate protocol mutually") - } - return cn, nil -} - -// disableKeepAlives reports whether connections should be closed as -// soon as possible after handling the first request. -func (t *Transport) disableKeepAlives() bool { - return t.t1 != nil && t.t1.DisableKeepAlives -} - -func (t *Transport) expectContinueTimeout() time.Duration { - if t.t1 == nil { - return 0 - } - return transportExpectContinueTimeout(t.t1) -} - -func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) { - return t.newClientConn(c, false) -} - -func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, error) { - cc := &ClientConn{ - t: t, - tconn: c, - readerDone: make(chan struct{}), - nextStreamID: 1, - maxFrameSize: 16 << 10, // spec default - initialWindowSize: 65535, // spec default - maxConcurrentStreams: 1000, // "infinite", per spec. 1000 seems good enough. - peerMaxHeaderListSize: 0xffffffffffffffff, // "infinite", per spec. Use 2^64-1 instead. - streams: make(map[uint32]*clientStream), - singleUse: singleUse, - wantSettingsAck: true, - pings: make(map[[8]byte]chan struct{}), - } - if d := t.idleConnTimeout(); d != 0 { - cc.idleTimeout = d - cc.idleTimer = time.AfterFunc(d, cc.onIdleTimeout) - } - 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)) - - // TODO: adjust this writer size to account for frame size + - // MTU + crypto/tls record padding. - cc.bw = bufio.NewWriter(stickyErrWriter{c, &cc.werr}) - cc.br = bufio.NewReader(c) - cc.fr = NewFramer(cc.bw, cc.br) - cc.fr.ReadMetaHeaders = hpack.NewDecoder(initialHeaderTableSize, nil) - cc.fr.MaxHeaderListSize = t.maxHeaderListSize() - - // TODO: SetMaxDynamicTableSize, SetMaxDynamicTableSizeLimit on - // henc in response to SETTINGS frames? - cc.henc = hpack.NewEncoder(&cc.hbuf) - - if t.AllowHTTP { - cc.nextStreamID = 3 - } - - if cs, ok := c.(connectionStater); ok { - state := cs.ConnectionState() - cc.tlsState = &state - } - - initialSettings := []Setting{ - {ID: SettingEnablePush, Val: 0}, - {ID: SettingInitialWindowSize, Val: transportDefaultStreamFlow}, - } - 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) - cc.bw.Flush() - if cc.werr != nil { - return nil, cc.werr - } - - go cc.readLoop() - return cc, nil -} - -func (cc *ClientConn) setGoAway(f *GoAwayFrame) { - cc.mu.Lock() - defer cc.mu.Unlock() - - old := cc.goAway - cc.goAway = f - - // Merge the previous and current GoAway error frames. - if cc.goAwayDebug == "" { - cc.goAwayDebug = string(f.DebugData()) - } - if old != nil && old.ErrCode != ErrCodeNo { - cc.goAway.ErrCode = old.ErrCode - } - last := f.LastStreamID - for streamID, cs := range cc.streams { - if streamID > last { - select { - case cs.resc <- resAndError{err: errClientConnGotGoAway}: - default: - } - } - } -} - -// CanTakeNewRequest reports whether the connection can take a new request, -// meaning it has not been closed or received or sent a GOAWAY. -func (cc *ClientConn) CanTakeNewRequest() bool { - cc.mu.Lock() - defer cc.mu.Unlock() - return cc.canTakeNewRequestLocked() -} - -// clientConnIdleState describes the suitability of a client -// connection to initiate a new RoundTrip request. -type clientConnIdleState struct { - canTakeNewRequest bool - freshConn bool // whether it's unused by any previous request -} - -func (cc *ClientConn) idleState() clientConnIdleState { - cc.mu.Lock() - defer cc.mu.Unlock() - return cc.idleStateLocked() -} - -func (cc *ClientConn) idleStateLocked() (st clientConnIdleState) { - if cc.singleUse && cc.nextStreamID > 1 { - return - } - st.canTakeNewRequest = cc.goAway == nil && !cc.closed && !cc.closing && - int64(cc.nextStreamID)+int64(cc.pendingRequests) < math.MaxInt32 - st.freshConn = cc.nextStreamID == 1 && st.canTakeNewRequest - return -} - -func (cc *ClientConn) canTakeNewRequestLocked() bool { - st := cc.idleStateLocked() - return st.canTakeNewRequest -} - -// onIdleTimeout is called from a time.AfterFunc goroutine. It will -// only be called when we're idle, but because we're coming from a new -// goroutine, there could be a new request coming in at the same time, -// so this simply calls the synchronized closeIfIdle to shut down this -// connection. The timer could just call closeIfIdle, but this is more -// clear. -func (cc *ClientConn) onIdleTimeout() { - cc.closeIfIdle() -} - -func (cc *ClientConn) closeIfIdle() { - cc.mu.Lock() - if len(cc.streams) > 0 { - cc.mu.Unlock() - 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() -} - -var shutdownEnterWaitStateHook = func() {} - -// Shutdown gracefully close the client connection, waiting for running streams to complete. -// Public implementation is in go17.go and not_go17.go -func (cc *ClientConn) shutdown(ctx contextContext) error { - if err := cc.sendGoAway(); err != nil { - return err - } - // Wait for all in-flight streams to complete or connection to close - done := make(chan error, 1) - cancelled := false // guarded by cc.mu - go func() { - cc.mu.Lock() - defer cc.mu.Unlock() - for { - if len(cc.streams) == 0 || cc.closed { - cc.closed = true - done <- cc.tconn.Close() - break - } - if cancelled { - break - } - cc.cond.Wait() - } - }() - shutdownEnterWaitStateHook() - select { - case err := <-done: - return err - case <-ctx.Done(): - cc.mu.Lock() - // Free the goroutine above - cancelled = true - cc.cond.Broadcast() - cc.mu.Unlock() - return ctx.Err() - } -} - -func (cc *ClientConn) sendGoAway() error { - cc.mu.Lock() - defer cc.mu.Unlock() - cc.wmu.Lock() - defer cc.wmu.Unlock() - if cc.closing { - // GOAWAY sent already - return nil - } - // Send a graceful shutdown frame to server - maxStreamID := cc.nextStreamID - if err := cc.fr.WriteGoAway(maxStreamID, ErrCodeNo, nil); err != nil { - return err - } - if err := cc.bw.Flush(); err != nil { - return err - } - // Prevent new requests - cc.closing = true - return nil -} - -// Close closes the client connection immediately. -// -// In-flight requests are interrupted. For a graceful shutdown, use Shutdown instead. -func (cc *ClientConn) Close() error { - cc.mu.Lock() - defer cc.cond.Broadcast() - defer cc.mu.Unlock() - err := errors.New("http2: client connection force closed via ClientConn.Close") - for id, cs := range cc.streams { - select { - case cs.resc <- resAndError{err: err}: - default: - } - cs.bufPipe.CloseWithError(err) - delete(cc.streams, id) - } - cc.closed = true - return cc.tconn.Close() -} - -const maxAllocFrameSize = 512 << 10 - -// frameBuffer returns a scratch buffer suitable for writing DATA frames. -// They're capped at the min of the peer's max frame size or 512KB -// (kinda arbitrarily), but definitely capped so we don't allocate 4GB -// bufers. -func (cc *ClientConn) frameScratchBuffer() []byte { - cc.mu.Lock() - size := cc.maxFrameSize - if size > maxAllocFrameSize { - size = maxAllocFrameSize - } - for i, buf := range cc.freeBuf { - if len(buf) >= int(size) { - cc.freeBuf[i] = nil - cc.mu.Unlock() - return buf[:size] - } - } - cc.mu.Unlock() - return make([]byte, size) -} - -func (cc *ClientConn) putFrameScratchBuffer(buf []byte) { - cc.mu.Lock() - defer cc.mu.Unlock() - const maxBufs = 4 // arbitrary; 4 concurrent requests per conn? investigate. - if len(cc.freeBuf) < maxBufs { - cc.freeBuf = append(cc.freeBuf, buf) - return - } - for i, old := range cc.freeBuf { - if old == nil { - cc.freeBuf[i] = buf - return - } - } - // forget about it. -} - -// errRequestCanceled is a copy of net/http's errRequestCanceled because it's not -// exported. At least they'll be DeepEqual for h1-vs-h2 comparisons tests. -var errRequestCanceled = errors.New("net/http: request canceled") - -func commaSeparatedTrailers(req *http.Request) (string, error) { - keys := make([]string, 0, len(req.Trailer)) - for k := range req.Trailer { - k = http.CanonicalHeaderKey(k) - switch k { - case "Transfer-Encoding", "Trailer", "Content-Length": - return "", &badStringError{"invalid Trailer key", k} - } - keys = append(keys, k) - } - if len(keys) > 0 { - sort.Strings(keys) - return strings.Join(keys, ","), nil - } - return "", nil -} - -func (cc *ClientConn) responseHeaderTimeout() time.Duration { - if cc.t.t1 != nil { - return cc.t.t1.ResponseHeaderTimeout - } - // No way to do this (yet?) with just an http2.Transport. Probably - // no need. Request.Cancel this is the new way. We only need to support - // this for compatibility with the old http.Transport fields when - // we're doing transparent http2. - return 0 -} - -// checkConnHeaders checks whether req has any invalid connection-level headers. -// per RFC 7540 section 8.1.2.2: Connection-Specific Header Fields. -// Certain headers are special-cased as okay but not transmitted later. -func checkConnHeaders(req *http.Request) error { - if v := req.Header.Get("Upgrade"); v != "" { - return fmt.Errorf("http2: invalid Upgrade request header: %q", req.Header["Upgrade"]) - } - if vv := req.Header["Transfer-Encoding"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && vv[0] != "chunked") { - return fmt.Errorf("http2: invalid Transfer-Encoding request header: %q", vv) - } - if vv := req.Header["Connection"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && !strings.EqualFold(vv[0], "close") && !strings.EqualFold(vv[0], "keep-alive")) { - return fmt.Errorf("http2: invalid Connection request header: %q", vv) - } - return nil -} - -// actualContentLength returns a sanitized version of -// req.ContentLength, where 0 actually means zero (not unknown) and -1 -// means unknown. -func actualContentLength(req *http.Request) int64 { - if req.Body == nil || reqBodyIsNoBody(req.Body) { - return 0 - } - if req.ContentLength != 0 { - return req.ContentLength - } - return -1 -} - -func (cc *ClientConn) RoundTrip(req *http.Request) (*http.Response, error) { - resp, _, err := cc.roundTrip(req) - return resp, err -} - -func (cc *ClientConn) roundTrip(req *http.Request) (res *http.Response, gotErrAfterReqBodyWrite bool, err error) { - if err := checkConnHeaders(req); err != nil { - return nil, false, err - } - if cc.idleTimer != nil { - cc.idleTimer.Stop() - } - - trailers, err := commaSeparatedTrailers(req) - if err != nil { - return nil, false, err - } - hasTrailers := trailers != "" - - cc.mu.Lock() - if err := cc.awaitOpenSlotForRequest(req); err != nil { - cc.mu.Unlock() - return nil, false, err - } - - body := req.Body - contentLen := actualContentLength(req) - hasBody := contentLen != 0 - - // TODO(bradfitz): this is a copy of the logic in net/http. Unify somewhere? - var requestedGzip bool - if !cc.t.disableCompression() && - req.Header.Get("Accept-Encoding") == "" && - req.Header.Get("Range") == "" && - req.Method != "HEAD" { - // Request gzip only, not deflate. Deflate is ambiguous and - // not as universally supported anyway. - // See: http://www.gzip.org/zlib/zlib_faq.html#faq38 - // - // Note that we don't request this for HEAD requests, - // due to a bug in nginx: - // http://trac.nginx.org/nginx/ticket/358 - // https://golang.org/issue/5522 - // - // We don't request gzip if the request is for a range, since - // auto-decoding a portion of a gzipped document will just fail - // anyway. See https://golang.org/issue/8923 - requestedGzip = true - } - - // we send: HEADERS{1}, CONTINUATION{0,} + DATA{0,} (DATA is - // sent by writeRequestBody below, along with any Trailers, - // again in form HEADERS{1}, CONTINUATION{0,}) - hdrs, err := cc.encodeHeaders(req, requestedGzip, trailers, contentLen) - if err != nil { - cc.mu.Unlock() - return nil, false, err - } - - cs := cc.newStream() - cs.req = req - cs.trace = requestTrace(req) - cs.requestedGzip = requestedGzip - bodyWriter := cc.t.getBodyWriterState(cs, body) - cs.on100 = bodyWriter.on100 - - cc.wmu.Lock() - endStream := !hasBody && !hasTrailers - werr := cc.writeHeaders(cs.ID, endStream, int(cc.maxFrameSize), hdrs) - cc.wmu.Unlock() - traceWroteHeaders(cs.trace) - cc.mu.Unlock() - - if werr != nil { - if hasBody { - req.Body.Close() // per RoundTripper contract - bodyWriter.cancel() - } - cc.forgetStreamID(cs.ID) - // Don't bother sending a RST_STREAM (our write already failed; - // no need to keep writing) - traceWroteRequest(cs.trace, werr) - return nil, false, werr - } - - var respHeaderTimer <-chan time.Time - if hasBody { - bodyWriter.scheduleBodyWrite() - } else { - traceWroteRequest(cs.trace, nil) - if d := cc.responseHeaderTimeout(); d != 0 { - timer := time.NewTimer(d) - defer timer.Stop() - respHeaderTimer = timer.C - } - } - - readLoopResCh := cs.resc - bodyWritten := false - ctx := reqContext(req) - - handleReadLoopResponse := func(re resAndError) (*http.Response, bool, 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, cs.getStartedWrite(), re.err - } - res.Request = req - res.TLS = cc.tlsState - return res, false, nil - } - - for { - select { - case re := <-readLoopResCh: - return handleReadLoopResponse(re) - case <-respHeaderTimer: - if !hasBody || bodyWritten { - cc.writeStreamReset(cs.ID, ErrCodeCancel, nil) - } else { - bodyWriter.cancel() - cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel) - } - cc.forgetStreamID(cs.ID) - return nil, cs.getStartedWrite(), errTimeout - case <-ctx.Done(): - if !hasBody || bodyWritten { - cc.writeStreamReset(cs.ID, ErrCodeCancel, nil) - } else { - bodyWriter.cancel() - cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel) - } - cc.forgetStreamID(cs.ID) - return nil, cs.getStartedWrite(), ctx.Err() - case <-req.Cancel: - if !hasBody || bodyWritten { - cc.writeStreamReset(cs.ID, ErrCodeCancel, nil) - } else { - bodyWriter.cancel() - cs.abortRequestBodyWrite(errStopReqBodyWriteAndCancel) - } - cc.forgetStreamID(cs.ID) - return nil, cs.getStartedWrite(), errRequestCanceled - case <-cs.peerReset: - // processResetStream already removed the - // stream from the streams map; no need for - // forgetStreamID. - return nil, cs.getStartedWrite(), 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, cs.getStartedWrite(), err - } - bodyWritten = true - if d := cc.responseHeaderTimeout(); d != 0 { - timer := time.NewTimer(d) - defer timer.Stop() - respHeaderTimer = timer.C - } - } - } -} - -// awaitOpenSlotForRequest waits until len(streams) < maxConcurrentStreams. -// Must hold cc.mu. -func (cc *ClientConn) awaitOpenSlotForRequest(req *http.Request) error { - var waitingForConn chan struct{} - var waitingForConnErr error // guarded by cc.mu - for { - cc.lastActive = time.Now() - if cc.closed || !cc.canTakeNewRequestLocked() { - if waitingForConn != nil { - close(waitingForConn) - } - return errClientConnUnusable - } - if int64(len(cc.streams))+1 <= int64(cc.maxConcurrentStreams) { - if waitingForConn != nil { - close(waitingForConn) - } - return nil - } - // Unfortunately, we cannot wait on a condition variable and channel at - // the same time, so instead, we spin up a goroutine to check if the - // request is canceled while we wait for a slot to open in the connection. - if waitingForConn == nil { - waitingForConn = make(chan struct{}) - go func() { - if err := awaitRequestCancel(req, waitingForConn); err != nil { - cc.mu.Lock() - waitingForConnErr = err - cc.cond.Broadcast() - cc.mu.Unlock() - } - }() - } - cc.pendingRequests++ - cc.cond.Wait() - cc.pendingRequests-- - if waitingForConnErr != nil { - return waitingForConnErr - } - } -} - -// requires cc.wmu be held -func (cc *ClientConn) writeHeaders(streamID uint32, endStream bool, maxFrameSize int, hdrs []byte) error { - first := true // first frame written (HEADERS is first, then CONTINUATION) - for len(hdrs) > 0 && cc.werr == nil { - chunk := hdrs - if len(chunk) > maxFrameSize { - chunk = chunk[:maxFrameSize] - } - hdrs = hdrs[len(chunk):] - endHeaders := len(hdrs) == 0 - if first { - cc.fr.WriteHeaders(HeadersFrameParam{ - StreamID: streamID, - BlockFragment: chunk, - EndStream: endStream, - EndHeaders: endHeaders, - }) - first = false - } else { - cc.fr.WriteContinuation(streamID, endHeaders, chunk) - } - } - // TODO(bradfitz): this Flush could potentially block (as - // could the WriteHeaders call(s) above), which means they - // wouldn't respond to Request.Cancel being readable. That's - // rare, but this should probably be in a goroutine. - cc.bw.Flush() - return cc.werr -} - -// internal error values; they don't escape to callers -var ( - // abort request body write; don't send cancel - errStopReqBodyWrite = errors.New("http2: aborting request body write") - - // abort request body write, but send stream reset of cancel. - errStopReqBodyWriteAndCancel = errors.New("http2: canceling request") -) - -func (cs *clientStream) writeRequestBody(body io.Reader, bodyCloser io.Closer) (err error) { - cc := cs.cc - sentEnd := false // whether we sent the final DATA frame w/ END_STREAM - buf := cc.frameScratchBuffer() - defer cc.putFrameScratchBuffer(buf) - - defer func() { - traceWroteRequest(cs.trace, err) - // TODO: write h12Compare test showing whether - // Request.Body is closed by the Transport, - // and in multiple cases: server replies <=299 and >299 - // while still writing request body - cerr := bodyCloser.Close() - if err == nil { - err = cerr - } - }() - - req := cs.req - hasTrailers := req.Trailer != nil - - var sawEOF bool - for !sawEOF { - n, err := body.Read(buf) - if err == io.EOF { - sawEOF = true - err = nil - } else if err != nil { - return err - } - - remain := buf[:n] - for len(remain) > 0 && err == nil { - var allowed int32 - allowed, err = cs.awaitFlowControl(len(remain)) - switch { - case err == errStopReqBodyWrite: - return err - case err == errStopReqBodyWriteAndCancel: - cc.writeStreamReset(cs.ID, ErrCodeCancel, nil) - return err - case err != nil: - return err - } - cc.wmu.Lock() - data := remain[:allowed] - remain = remain[allowed:] - sentEnd = sawEOF && len(remain) == 0 && !hasTrailers - 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. - // If we change this, see comment below. - err = cc.bw.Flush() - } - cc.wmu.Unlock() - } - if err != nil { - return err - } - } - - 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() - trls, err = cc.encodeTrailers(req) - cc.mu.Unlock() - if err != nil { - cc.writeStreamReset(cs.ID, ErrCodeInternal, err) - cc.forgetStreamID(cs.ID) - return err - } - } - - cc.mu.Lock() - maxFrameSize := int(cc.maxFrameSize) - cc.mu.Unlock() - - cc.wmu.Lock() - defer cc.wmu.Unlock() - - // 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, maxFrameSize, trls) - } else { - err = cc.fr.WriteData(cs.ID, true, nil) - } - if ferr := cc.bw.Flush(); ferr != nil && err == nil { - err = ferr - } - return err -} - -// awaitFlowControl waits for [1, min(maxBytes, cc.cs.maxFrameSize)] flow -// control tokens from the server. -// It returns either the non-zero number of tokens taken or an error -// if the stream is dead. -func (cs *clientStream) awaitFlowControl(maxBytes int) (taken int32, err error) { - cc := cs.cc - cc.mu.Lock() - defer cc.mu.Unlock() - for { - if cc.closed { - return 0, errClientConnClosed - } - if cs.stopReqBody != nil { - return 0, cs.stopReqBody - } - if err := cs.checkResetOrDone(); err != nil { - return 0, err - } - if a := cs.flow.available(); a > 0 { - take := a - if int(take) > maxBytes { - - take = int32(maxBytes) // can't truncate int; take is int32 - } - if take > int32(cc.maxFrameSize) { - take = int32(cc.maxFrameSize) - } - cs.flow.take(take) - return take, nil - } - cc.cond.Wait() - } -} - -type badStringError struct { - what string - str string -} - -func (e *badStringError) Error() string { return fmt.Sprintf("%s %q", e.what, e.str) } - -// requires cc.mu be held. -func (cc *ClientConn) encodeHeaders(req *http.Request, addGzipHeader bool, trailers string, contentLength int64) ([]byte, error) { - cc.hbuf.Reset() - - host := req.Host - if host == "" { - host = req.URL.Host - } - host, err := httpguts.PunycodeHostPort(host) - if err != nil { - return nil, err - } - - 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) - for k, vv := range req.Header { - if !httpguts.ValidHeaderFieldName(k) { - return nil, fmt.Errorf("invalid HTTP header name %q", k) - } - for _, v := range vv { - if !httpguts.ValidHeaderFieldValue(v) { - return nil, fmt.Errorf("invalid HTTP header value %q for header %q", v, k) - } - } - } - - enumerateHeaders := func(f func(name, value string)) { - // 8.1.2.3 Request Pseudo-Header Fields - // The :path pseudo-header field includes the path and query parts of the - // target URI (the path-absolute production and optionally a '?' character - // followed by the query production (see Sections 3.3 and 3.4 of - // [RFC3986]). - f(":authority", host) - f(":method", req.Method) - if req.Method != "CONNECT" { - f(":path", path) - f(":scheme", req.URL.Scheme) - } - if trailers != "" { - f("trailer", trailers) - } - - var didUA bool - for k, vv := range req.Header { - if strings.EqualFold(k, "host") || strings.EqualFold(k, "content-length") { - // Host is :authority, already sent. - // Content-Length is automatic, set below. - continue - } else if strings.EqualFold(k, "connection") || strings.EqualFold(k, "proxy-connection") || - strings.EqualFold(k, "transfer-encoding") || strings.EqualFold(k, "upgrade") || - strings.EqualFold(k, "keep-alive") { - // Per 8.1.2.2 Connection-Specific Header - // Fields, don't send connection-specific - // fields. We have already checked if any - // are error-worthy so just ignore the rest. - continue - } else if strings.EqualFold(k, "user-agent") { - // Match Go's http1 behavior: at most one - // User-Agent. If set to nil or empty string, - // then omit it. Otherwise if not mentioned, - // include the default (below). - didUA = true - if len(vv) < 1 { - continue - } - vv = vv[:1] - if vv[0] == "" { - continue - } - - } - - for _, v := range vv { - f(k, v) - } - } - if shouldSendReqContentLength(req.Method, contentLength) { - f("content-length", strconv.FormatInt(contentLength, 10)) - } - if addGzipHeader { - f("accept-encoding", "gzip") - } - if !didUA { - f("user-agent", defaultUserAgent) - } - } - - // Do a first pass over the headers counting bytes to ensure - // we don't exceed cc.peerMaxHeaderListSize. This is done as a - // separate pass before encoding the headers to prevent - // modifying the hpack state. - hlSize := uint64(0) - enumerateHeaders(func(name, value string) { - hf := hpack.HeaderField{Name: name, Value: value} - hlSize += uint64(hf.Size()) - }) - - if hlSize > cc.peerMaxHeaderListSize { - return nil, errRequestHeaderListSize - } - - trace := requestTrace(req) - traceHeaders := traceHasWroteHeaderField(trace) - - // Header list size is ok. Write the headers. - enumerateHeaders(func(name, value string) { - name = strings.ToLower(name) - cc.writeHeader(name, value) - if traceHeaders { - traceWroteHeaderField(trace, name, value) - } - }) - - return cc.hbuf.Bytes(), nil -} - -// shouldSendReqContentLength reports whether the http2.Transport should send -// a "content-length" request header. This logic is basically a copy of the net/http -// transferWriter.shouldSendContentLength. -// The contentLength is the corrected contentLength (so 0 means actually 0, not unknown). -// -1 means unknown. -func shouldSendReqContentLength(method string, contentLength int64) bool { - if contentLength > 0 { - return true - } - if contentLength < 0 { - return false - } - // For zero bodies, whether we send a content-length depends on the method. - // It also kinda doesn't matter for http2 either way, with END_STREAM. - switch method { - case "POST", "PUT", "PATCH": - return true - default: - return false - } -} - -// requires cc.mu be held. -func (cc *ClientConn) encodeTrailers(req *http.Request) ([]byte, error) { - cc.hbuf.Reset() - - hlSize := uint64(0) - for k, vv := range req.Trailer { - for _, v := range vv { - hf := hpack.HeaderField{Name: k, Value: v} - hlSize += uint64(hf.Size()) - } - } - if hlSize > cc.peerMaxHeaderListSize { - return nil, errRequestHeaderListSize - } - - for k, vv := range req.Trailer { - // Transfer-Encoding, etc.. have already been filtered at the - // start of RoundTrip - lowKey := strings.ToLower(k) - for _, v := range vv { - cc.writeHeader(lowKey, v) - } - } - return cc.hbuf.Bytes(), nil -} - -func (cc *ClientConn) writeHeader(name, value string) { - if VerboseLogs { - log.Printf("http2: Transport encoding header %q = %q", name, value) - } - cc.henc.WriteField(hpack.HeaderField{Name: name, Value: value}) -} - -type resAndError struct { - res *http.Response - err error -} - -// requires cc.mu be held. -func (cc *ClientConn) newStream() *clientStream { - cs := &clientStream{ - cc: cc, - ID: cc.nextStreamID, - resc: make(chan resAndError, 1), - peerReset: make(chan struct{}), - done: make(chan struct{}), - } - cs.flow.add(int32(cc.initialWindowSize)) - cs.flow.setConnFlow(&cc.flow) - cs.inflow.add(transportDefaultStreamFlow) - cs.inflow.setConnFlow(&cc.inflow) - cc.nextStreamID += 2 - cc.streams[cs.ID] = cs - return cs -} - -func (cc *ClientConn) forgetStreamID(id uint32) { - cc.streamByID(id, true) -} - -func (cc *ClientConn) streamByID(id uint32, andRemove bool) *clientStream { - cc.mu.Lock() - defer cc.mu.Unlock() - cs := cc.streams[id] - if andRemove && cs != nil && !cc.closed { - cc.lastActive = time.Now() - delete(cc.streams, id) - if len(cc.streams) == 0 && cc.idleTimer != nil { - cc.idleTimer.Reset(cc.idleTimeout) - } - close(cs.done) - // Wake up checkResetOrDone via clientStream.awaitFlowControl and - // wake up RoundTrip if there is a pending request. - cc.cond.Broadcast() - } - return cs -} - -// clientConnReadLoop is the state owned by the clientConn's frame-reading readLoop. -type clientConnReadLoop struct { - cc *ClientConn - closeWhenIdle bool -} - -// readLoop runs in its own goroutine and reads and dispatches frames. -func (cc *ClientConn) readLoop() { - rl := &clientConnReadLoop{cc: cc} - defer rl.cleanup() - cc.readerErr = rl.run() - if ce, ok := cc.readerErr.(ConnectionError); ok { - cc.wmu.Lock() - cc.fr.WriteGoAway(0, ErrCode(ce), nil) - cc.wmu.Unlock() - } -} - -// GoAwayError is returned by the Transport when the server closes the -// TCP connection after sending a GOAWAY frame. -type GoAwayError struct { - LastStreamID uint32 - ErrCode ErrCode - DebugData string -} - -func (e GoAwayError) Error() string { - return fmt.Sprintf("http2: server sent GOAWAY and closed the connection; LastStreamID=%v, ErrCode=%v, debug=%q", - 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() - defer cc.t.connPool().MarkDead(cc) - defer close(cc.readerDone) - - if cc.idleTimer != nil { - cc.idleTimer.Stop() - } - - // Close any response bodies if the server closes prematurely. - // TODO: also do this if we've written the headers but not - // gotten a response yet. - err := cc.readerErr - cc.mu.Lock() - 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 cc.streams { - cs.bufPipe.CloseWithError(err) // no-op if already closed - select { - case cs.resc <- resAndError{err: err}: - default: - } - close(cs.done) - } - cc.closed = true - cc.cond.Broadcast() - cc.mu.Unlock() -} - -func (rl *clientConnReadLoop) run() error { - cc := rl.cc - rl.closeWhenIdle = cc.t.disableKeepAlives() || cc.singleUse - gotReply := false // ever saw a HEADERS reply - gotSettings := false - for { - f, err := cc.fr.ReadFrame() - if err != nil { - 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, false); cs != nil { - cs.cc.writeStreamReset(cs.ID, se.Code, err) - cs.cc.forgetStreamID(cs.ID) - if se.Cause == nil { - se.Cause = cc.fr.errDetail - } - rl.endStreamError(cs, se) - } - continue - } else if err != nil { - return err - } - 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) { - case *MetaHeadersFrame: - err = rl.processHeaders(f) - maybeIdle = true - gotReply = true - case *DataFrame: - err = rl.processData(f) - maybeIdle = true - case *GoAwayFrame: - err = rl.processGoAway(f) - maybeIdle = true - case *RSTStreamFrame: - err = rl.processResetStream(f) - maybeIdle = true - case *SettingsFrame: - err = rl.processSettings(f) - case *PushPromiseFrame: - err = rl.processPushPromise(f) - case *WindowUpdateFrame: - err = rl.processWindowUpdate(f) - case *PingFrame: - err = rl.processPing(f) - default: - 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 { - cc.closeIfIdle() - } - } -} - -func (rl *clientConnReadLoop) processHeaders(f *MetaHeadersFrame) error { - cc := rl.cc - cs := cc.streamByID(f.StreamID, false) - if cs == nil { - // We'd get here if we canceled a request while the - // server had its response still in flight. So if this - // was just something we canceled, ignore it. - return nil - } - if f.StreamEnded() { - // Issue 20521: If the stream has ended, streamByID() causes - // clientStream.done to be closed, which causes the request's bodyWriter - // to be closed with an errStreamClosed, which may be received by - // clientConn.RoundTrip before the result of processing these headers. - // Deferring stream closure allows the header processing to occur first. - // clientConn.RoundTrip may still receive the bodyWriter error first, but - // the fix for issue 16102 prioritises any response. - // - // Issue 22413: If there is no request body, we should close the - // stream before writing to cs.resc so that the stream is closed - // immediately once RoundTrip returns. - if cs.req.Body != nil { - defer cc.forgetStreamID(f.StreamID) - } else { - cc.forgetStreamID(f.StreamID) - } - } - if !cs.firstByte { - if cs.trace != nil { - // TODO(bradfitz): move first response byte earlier, - // when we first read the 9 byte header, not waiting - // until all the HEADERS+CONTINUATION frames have been - // merged. This works for now. - traceFirstResponseByte(cs.trace) - } - cs.firstByte = true - } - if !cs.pastHeaders { - cs.pastHeaders = true - } else { - return rl.processTrailers(cs, f) - } - - res, err := rl.handleResponse(cs, f) - if err != nil { - if _, ok := err.(ConnectionError); ok { - return err - } - // Any other error type is a stream error. - cs.cc.writeStreamReset(f.StreamID, ErrCodeProtocol, err) - cc.forgetStreamID(cs.ID) - cs.resc <- resAndError{err: err} - return nil // return nil from process* funcs to keep conn alive - } - if res == nil { - // (nil, nil) special case. See handleResponse docs. - return nil - } - cs.resTrailer = &res.Trailer - cs.resc <- resAndError{res: res} - return nil -} - -// may return error types nil, or ConnectionError. Any other error value -// is a StreamError of type ErrCodeProtocol. The returned error in that case -// is the detail. -// -// As a special case, handleResponse may return (nil, nil) to skip the -// frame (currently only used for 1xx responses). -func (rl *clientConnReadLoop) handleResponse(cs *clientStream, f *MetaHeadersFrame) (*http.Response, error) { - if f.Truncated { - return nil, errResponseHeaderListSize - } - - status := f.PseudoValue("status") - if status == "" { - return nil, errors.New("malformed response from server: missing status pseudo header") - } - statusCode, err := strconv.Atoi(status) - if err != nil { - return nil, errors.New("malformed response from server: malformed non-numeric status pseudo header") - } - - header := make(http.Header) - res := &http.Response{ - Proto: "HTTP/2.0", - ProtoMajor: 2, - Header: header, - StatusCode: statusCode, - Status: status + " " + http.StatusText(statusCode), - } - for _, hf := range f.RegularFields() { - key := http.CanonicalHeaderKey(hf.Name) - if key == "Trailer" { - t := res.Trailer - if t == nil { - t = make(http.Header) - res.Trailer = t - } - foreachHeaderElement(hf.Value, func(v string) { - t[http.CanonicalHeaderKey(v)] = nil - }) - } else { - header[key] = append(header[key], hf.Value) - } - } - - if statusCode >= 100 && statusCode <= 199 { - cs.num1xx++ - const max1xxResponses = 5 // arbitrary bound on number of informational responses, same as net/http - if cs.num1xx > max1xxResponses { - return nil, errors.New("http2: too many 1xx informational responses") - } - if fn := cs.get1xxTraceFunc(); fn != nil { - if err := fn(statusCode, textproto.MIMEHeader(header)); err != nil { - return nil, err - } - } - if statusCode == 100 { - traceGot100Continue(cs.trace) - if cs.on100 != nil { - cs.on100() // forces any write delay timer to fire - } - } - cs.pastHeaders = false // do it all again - return nil, nil - } - - streamEnded := f.StreamEnded() - isHead := cs.req.Method == "HEAD" - if !streamEnded || isHead { - res.ContentLength = -1 - if clens := res.Header["Content-Length"]; len(clens) == 1 { - if clen64, err := strconv.ParseInt(clens[0], 10, 64); err == nil { - res.ContentLength = clen64 - } else { - // TODO: care? unlike http/1, it won't mess up our framing, so it's - // more safe smuggling-wise to ignore. - } - } else if len(clens) > 1 { - // TODO: care? unlike http/1, it won't mess up our framing, so it's - // more safe smuggling-wise to ignore. - } - } - - if streamEnded || isHead { - res.Body = noBody - return res, nil - } - - cs.bufPipe = pipe{b: &dataBuffer{expected: res.ContentLength}} - cs.bytesRemain = res.ContentLength - res.Body = transportResponseBody{cs} - go cs.awaitRequestCancel(cs.req) - - if cs.requestedGzip && res.Header.Get("Content-Encoding") == "gzip" { - res.Header.Del("Content-Encoding") - res.Header.Del("Content-Length") - res.ContentLength = -1 - res.Body = &gzipReader{body: res.Body} - setResponseUncompressed(res) - } - return res, nil -} - -func (rl *clientConnReadLoop) processTrailers(cs *clientStream, f *MetaHeadersFrame) error { - if cs.pastTrailers { - // Too many HEADERS frames for this stream. - return ConnectionError(ErrCodeProtocol) - } - cs.pastTrailers = true - if !f.StreamEnded() { - // We expect that any headers for trailers also - // has END_STREAM. - return ConnectionError(ErrCodeProtocol) - } - if len(f.PseudoFields()) > 0 { - // No pseudo header fields are defined for trailers. - // TODO: ConnectionError might be overly harsh? Check. - return ConnectionError(ErrCodeProtocol) - } - - trailer := make(http.Header) - for _, hf := range f.RegularFields() { - key := http.CanonicalHeaderKey(hf.Name) - trailer[key] = append(trailer[key], hf.Value) - } - cs.trailer = trailer - - rl.endStream(cs) - return nil -} - -// transportResponseBody is the concrete type of Transport.RoundTrip's -// Response.Body. It is an io.ReadCloser. On Read, it reads from cs.body. -// On Close it sends RST_STREAM if EOF wasn't already seen. -type transportResponseBody struct { - cs *clientStream -} - -func (b transportResponseBody) Read(p []byte) (n int, err error) { - cs := b.cs - cc := cs.cc - - if cs.readErr != nil { - return 0, cs.readErr - } - n, err = b.cs.bufPipe.Read(p) - if cs.bytesRemain != -1 { - if int64(n) > cs.bytesRemain { - n = int(cs.bytesRemain) - if err == nil { - err = errors.New("net/http: server replied with more than declared Content-Length; truncated") - cc.writeStreamReset(cs.ID, ErrCodeProtocol, err) - } - cs.readErr = err - return int(cs.bytesRemain), err - } - cs.bytesRemain -= int64(n) - if err == io.EOF && cs.bytesRemain > 0 { - err = io.ErrUnexpectedEOF - cs.readErr = err - return n, err - } - } - if n == 0 { - // No flow control tokens to send back. - return - } - - cc.mu.Lock() - defer cc.mu.Unlock() - - var connAdd, streamAdd int32 - // Check the conn-level first, before the stream-level. - if v := cc.inflow.available(); v < transportDefaultConnFlow/2 { - connAdd = transportDefaultConnFlow - v - cc.inflow.add(connAdd) - } - if err == nil { // No need to refresh if the stream is over or failed. - // Consider any buffered body data (read from the conn but not - // consumed by the client) when computing flow control for this - // stream. - v := int(cs.inflow.available()) + cs.bufPipe.Len() - if v < transportDefaultStreamFlow-transportDefaultStreamMinRefresh { - streamAdd = int32(transportDefaultStreamFlow - v) - cs.inflow.add(streamAdd) - } - } - if connAdd != 0 || streamAdd != 0 { - cc.wmu.Lock() - defer cc.wmu.Unlock() - if connAdd != 0 { - cc.fr.WriteWindowUpdate(0, mustUint31(connAdd)) - } - if streamAdd != 0 { - cc.fr.WriteWindowUpdate(cs.ID, mustUint31(streamAdd)) - } - cc.bw.Flush() - } - return -} - -var errClosedResponseBody = errors.New("http2: response body closed") - -func (b transportResponseBody) Close() error { - cs := b.cs - 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) - cs.didReset = true - } - // 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) - cc.forgetStreamID(cs.ID) - return nil -} - -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 - cc.mu.Unlock() - if f.StreamID >= neverSent { - // We never asked for this. - cc.logf("http2: Transport received unsolicited DATA frame; closing connection") - return ConnectionError(ErrCodeProtocol) - } - // We probably did ask for this, but canceled. Just ignore it. - // 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 !cs.firstByte { - cc.logf("protocol error: received DATA before a HEADERS frame") - rl.endStreamError(cs, StreamError{ - StreamID: f.StreamID, - Code: ErrCodeProtocol, - }) - return nil - } - if f.Length > 0 { - if cs.req.Method == "HEAD" && len(data) > 0 { - cc.logf("protocol error: received DATA on a HEAD request") - rl.endStreamError(cs, StreamError{ - StreamID: f.StreamID, - Code: ErrCodeProtocol, - }) - return nil - } - // Check connection-level flow control. - cc.mu.Lock() - 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. - var refund int - if pad := int(f.Length) - len(data); pad > 0 { - refund += pad - } - // Return len(data) now if the stream is already closed, - // since data will never be read. - didReset := cs.didReset - if didReset { - refund += len(data) - } - if refund > 0 { - cc.inflow.add(int32(refund)) - cc.wmu.Lock() - cc.fr.WriteWindowUpdate(0, uint32(refund)) - if !didReset { - cs.inflow.add(int32(refund)) - cc.fr.WriteWindowUpdate(cs.ID, uint32(refund)) - } - cc.bw.Flush() - cc.wmu.Unlock() - } - cc.mu.Unlock() - - if len(data) > 0 && !didReset { - if _, err := cs.bufPipe.Write(data); err != nil { - rl.endStreamError(cs, err) - return err - } - } - } - - if f.StreamEnded() { - rl.endStream(cs) - } - return nil -} - -var errInvalidTrailers = errors.New("http2: invalid trailers") - -func (rl *clientConnReadLoop) endStream(cs *clientStream) { - // TODO: check that any declared content-length matches, like - // server.go's (*stream).endStream method. - rl.endStreamError(cs, nil) -} - -func (rl *clientConnReadLoop) endStreamError(cs *clientStream, err error) { - var code func() - if err == nil { - err = io.EOF - code = cs.copyTrailers - } - if isConnectionCloseRequest(cs.req) { - rl.closeWhenIdle = true - } - cs.bufPipe.closeWithErrorAndCode(err, code) - - select { - case cs.resc <- resAndError{err: err}: - default: - } -} - -func (cs *clientStream) copyTrailers() { - for k, vv := range cs.trailer { - t := cs.resTrailer - if *t == nil { - *t = make(http.Header) - } - (*t)[k] = vv - } -} - -func (rl *clientConnReadLoop) processGoAway(f *GoAwayFrame) error { - cc := rl.cc - cc.t.connPool().MarkDead(cc) - if f.ErrCode != 0 { - // TODO: deal with GOAWAY more. particularly the error code - cc.vlogf("transport got GOAWAY with error code = %v", f.ErrCode) - } - cc.setGoAway(f) - return nil -} - -func (rl *clientConnReadLoop) processSettings(f *SettingsFrame) error { - cc := rl.cc - cc.mu.Lock() - defer cc.mu.Unlock() - - 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 SettingMaxHeaderListSize: - cc.peerMaxHeaderListSize = uint64(s.Val) - case SettingInitialWindowSize: - // 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) - } - - // 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. - cc.vlogf("Unhandled Setting: %v", s) - } - 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 { - cc := rl.cc - cs := cc.streamByID(f.StreamID, false) - if f.StreamID != 0 && cs == nil { - return nil - } - - cc.mu.Lock() - defer cc.mu.Unlock() - - fl := &cc.flow - if cs != nil { - fl = &cs.flow - } - if !fl.add(int32(f.Increment)) { - return ConnectionError(ErrCodeFlowControl) - } - cc.cond.Broadcast() - return nil -} - -func (rl *clientConnReadLoop) processResetStream(f *RSTStreamFrame) error { - cs := rl.cc.streamByID(f.StreamID, true) - if cs == nil { - // TODO: return error if server tries to RST_STEAM an idle stream - return nil - } - select { - case <-cs.peerReset: - // Already reset. - // This is the only goroutine - // which closes this, so there - // isn't a race. - default: - err := streamError(cs.ID, f.ErrCode) - cs.resetErr = err - close(cs.peerReset) - cs.bufPipe.CloseWithError(err) - cs.cc.cond.Broadcast() // wake up checkResetOrDone via clientStream.awaitFlowControl - } - return nil -} - -// Ping sends a PING frame to the server and waits for the ack. -// Public implementation is in go17.go and not_go17.go -func (cc *ClientConn) ping(ctx contextContext) error { - c := make(chan struct{}) - // Generate a random payload - var p [8]byte - for { - if _, err := rand.Read(p[:]); err != nil { - return err - } - cc.mu.Lock() - // check for dup before insert - if _, found := cc.pings[p]; !found { - cc.pings[p] = c - cc.mu.Unlock() - break - } - cc.mu.Unlock() - } - cc.wmu.Lock() - if err := cc.fr.WritePing(false, p); err != nil { - cc.wmu.Unlock() - return err - } - if err := cc.bw.Flush(); err != nil { - cc.wmu.Unlock() - return err - } - cc.wmu.Unlock() - select { - case <-c: - return nil - case <-ctx.Done(): - return ctx.Err() - case <-cc.readerDone: - // connection closed - return cc.readerErr - } -} - -func (rl *clientConnReadLoop) processPing(f *PingFrame) error { - if f.IsAck() { - cc := rl.cc - cc.mu.Lock() - defer cc.mu.Unlock() - // If ack, notify listener if any - if c, ok := cc.pings[f.Data]; ok { - close(c) - delete(cc.pings, f.Data) - } - return nil - } - cc := rl.cc - cc.wmu.Lock() - defer cc.wmu.Unlock() - if err := cc.fr.WritePing(true, f.Data); err != nil { - return err - } - return cc.bw.Flush() -} - -func (rl *clientConnReadLoop) processPushPromise(f *PushPromiseFrame) error { - // We told the peer we don't want them. - // Spec says: - // "PUSH_PROMISE MUST NOT be sent if the SETTINGS_ENABLE_PUSH - // setting of the peer endpoint is set to 0. An endpoint that - // has set this setting and has received acknowledgement MUST - // treat the receipt of a PUSH_PROMISE frame as a connection - // error (Section 5.4.1) of type PROTOCOL_ERROR." - return ConnectionError(ErrCodeProtocol) -} - -func (cc *ClientConn) writeStreamReset(streamID uint32, code ErrCode, err error) { - // 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() - cc.wmu.Unlock() -} - -var ( - errResponseHeaderListSize = errors.New("http2: response header list larger than advertised limit") - errRequestHeaderListSize = errors.New("http2: request header list larger than peer's advertised limit") - errPseudoTrailers = errors.New("http2: invalid pseudo header in trailers") -) - -func (cc *ClientConn) logf(format string, args ...interface{}) { - cc.t.logf(format, args...) -} - -func (cc *ClientConn) vlogf(format string, args ...interface{}) { - cc.t.vlogf(format, args...) -} - -func (t *Transport) vlogf(format string, args ...interface{}) { - if VerboseLogs { - t.logf(format, args...) - } -} - -func (t *Transport) logf(format string, args ...interface{}) { - log.Printf(format, args...) -} - -var noBody io.ReadCloser = ioutil.NopCloser(bytes.NewReader(nil)) - -func strSliceContains(ss []string, s string) bool { - for _, v := range ss { - if v == s { - return true - } - } - return false -} - -type erringRoundTripper struct{ err error } - -func (rt erringRoundTripper) RoundTrip(*http.Request) (*http.Response, error) { return nil, rt.err } - -// gzipReader wraps a response body so it can lazily -// call gzip.NewReader on the first call to Read -type gzipReader struct { - body io.ReadCloser // underlying Response.Body - zr *gzip.Reader // lazily-initialized gzip reader - zerr error // sticky error -} - -func (gz *gzipReader) Read(p []byte) (n int, err error) { - if gz.zerr != nil { - return 0, gz.zerr - } - if gz.zr == nil { - gz.zr, err = gzip.NewReader(gz.body) - if err != nil { - gz.zerr = err - return 0, err - } - } - return gz.zr.Read(p) -} - -func (gz *gzipReader) Close() error { - return gz.body.Close() -} - -type errorReader struct{ err error } - -func (r errorReader) Read(p []byte) (int, error) { return 0, r.err } - -// bodyWriterState encapsulates various state around the Transport's writing -// of the request body, particularly regarding doing delayed writes of the body -// when the request contains "Expect: 100-continue". -type bodyWriterState struct { - cs *clientStream - timer *time.Timer // if non-nil, we're doing a delayed write - fnonce *sync.Once // to call fn with - fn func() // the code to run in the goroutine, writing the body - resc chan error // result of fn's execution - delay time.Duration // how long we should delay a delayed write for -} - -func (t *Transport) getBodyWriterState(cs *clientStream, body io.Reader) (s bodyWriterState) { - s.cs = cs - if body == nil { - return - } - resc := make(chan error, 1) - s.resc = resc - s.fn = func() { - cs.cc.mu.Lock() - cs.startedWrite = true - cs.cc.mu.Unlock() - resc <- cs.writeRequestBody(body, cs.req.Body) - } - s.delay = t.expectContinueTimeout() - if s.delay == 0 || - !httpguts.HeaderValuesContainsToken( - cs.req.Header["Expect"], - "100-continue") { - return - } - s.fnonce = new(sync.Once) - - // Arm the timer with a very large duration, which we'll - // intentionally lower later. It has to be large now because - // we need a handle to it before writing the headers, but the - // s.delay value is defined to not start until after the - // request headers were written. - const hugeDuration = 365 * 24 * time.Hour - s.timer = time.AfterFunc(hugeDuration, func() { - s.fnonce.Do(s.fn) - }) - return -} - -func (s bodyWriterState) cancel() { - if s.timer != nil { - s.timer.Stop() - } -} - -func (s bodyWriterState) on100() { - if s.timer == nil { - // If we didn't do a delayed write, ignore the server's - // bogus 100 continue response. - return - } - s.timer.Stop() - go func() { s.fnonce.Do(s.fn) }() -} - -// scheduleBodyWrite starts writing the body, either immediately (in -// the common case) or after the delay timeout. It should not be -// called until after the headers have been written. -func (s bodyWriterState) scheduleBodyWrite() { - if s.timer == nil { - // We're not doing a delayed write (see - // getBodyWriterState), so just start the writing - // goroutine immediately. - go s.fn() - return - } - traceWait100Continue(s.cs.trace) - if s.timer.Stop() { - s.timer.Reset(s.delay) - } -} - -// isConnectionCloseRequest reports whether req should use its own -// connection for a single request and then close the connection. -func isConnectionCloseRequest(req *http.Request) bool { - return req.Close || httpguts.HeaderValuesContainsToken(req.Header["Connection"], "close") -} |