diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/internal/transport/controlbuf.go')
| -rw-r--r-- | vendor/google.golang.org/grpc/internal/transport/controlbuf.go | 856 |
1 files changed, 0 insertions, 856 deletions
diff --git a/vendor/google.golang.org/grpc/internal/transport/controlbuf.go b/vendor/google.golang.org/grpc/internal/transport/controlbuf.go deleted file mode 100644 index ce135c4..0000000 --- a/vendor/google.golang.org/grpc/internal/transport/controlbuf.go +++ /dev/null @@ -1,856 +0,0 @@ -/* - * - * Copyright 2014 gRPC authors. - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - * - */ - -package transport - -import ( - "bytes" - "fmt" - "runtime" - "sync" - - "golang.org/x/net/http2" - "golang.org/x/net/http2/hpack" -) - -var updateHeaderTblSize = func(e *hpack.Encoder, v uint32) { - e.SetMaxDynamicTableSizeLimit(v) -} - -type itemNode struct { - it interface{} - next *itemNode -} - -type itemList struct { - head *itemNode - tail *itemNode -} - -func (il *itemList) enqueue(i interface{}) { - n := &itemNode{it: i} - if il.tail == nil { - il.head, il.tail = n, n - return - } - il.tail.next = n - il.tail = n -} - -// peek returns the first item in the list without removing it from the -// list. -func (il *itemList) peek() interface{} { - return il.head.it -} - -func (il *itemList) dequeue() interface{} { - if il.head == nil { - return nil - } - i := il.head.it - il.head = il.head.next - if il.head == nil { - il.tail = nil - } - return i -} - -func (il *itemList) dequeueAll() *itemNode { - h := il.head - il.head, il.tail = nil, nil - return h -} - -func (il *itemList) isEmpty() bool { - return il.head == nil -} - -// The following defines various control items which could flow through -// the control buffer of transport. They represent different aspects of -// control tasks, e.g., flow control, settings, streaming resetting, etc. - -// registerStream is used to register an incoming stream with loopy writer. -type registerStream struct { - streamID uint32 - wq *writeQuota -} - -// headerFrame is also used to register stream on the client-side. -type headerFrame struct { - streamID uint32 - hf []hpack.HeaderField - endStream bool // Valid on server side. - initStream func(uint32) (bool, error) // Used only on the client side. - onWrite func() - wq *writeQuota // write quota for the stream created. - cleanup *cleanupStream // Valid on the server side. - onOrphaned func(error) // Valid on client-side -} - -type cleanupStream struct { - streamID uint32 - idPtr *uint32 - rst bool - rstCode http2.ErrCode - onWrite func() -} - -type dataFrame struct { - streamID uint32 - endStream bool - h []byte - d []byte - // onEachWrite is called every time - // a part of d is written out. - onEachWrite func() -} - -type incomingWindowUpdate struct { - streamID uint32 - increment uint32 -} - -type outgoingWindowUpdate struct { - streamID uint32 - increment uint32 -} - -type incomingSettings struct { - ss []http2.Setting -} - -type outgoingSettings struct { - ss []http2.Setting -} - -type settingsAck struct { -} - -type incomingGoAway struct { -} - -type goAway struct { - code http2.ErrCode - debugData []byte - headsUp bool - closeConn bool -} - -type ping struct { - ack bool - data [8]byte -} - -type outFlowControlSizeRequest struct { - resp chan uint32 -} - -type outStreamState int - -const ( - active outStreamState = iota - empty - waitingOnStreamQuota -) - -type outStream struct { - id uint32 - state outStreamState - itl *itemList - bytesOutStanding int - wq *writeQuota - - next *outStream - prev *outStream -} - -func (s *outStream) deleteSelf() { - if s.prev != nil { - s.prev.next = s.next - } - if s.next != nil { - s.next.prev = s.prev - } - s.next, s.prev = nil, nil -} - -type outStreamList struct { - // Following are sentinel objects that mark the - // beginning and end of the list. They do not - // contain any item lists. All valid objects are - // inserted in between them. - // This is needed so that an outStream object can - // deleteSelf() in O(1) time without knowing which - // list it belongs to. - head *outStream - tail *outStream -} - -func newOutStreamList() *outStreamList { - head, tail := new(outStream), new(outStream) - head.next = tail - tail.prev = head - return &outStreamList{ - head: head, - tail: tail, - } -} - -func (l *outStreamList) enqueue(s *outStream) { - e := l.tail.prev - e.next = s - s.prev = e - s.next = l.tail - l.tail.prev = s -} - -// remove from the beginning of the list. -func (l *outStreamList) dequeue() *outStream { - b := l.head.next - if b == l.tail { - return nil - } - b.deleteSelf() - return b -} - -// controlBuffer is a way to pass information to loopy. -// Information is passed as specific struct types called control frames. -// A control frame not only represents data, messages or headers to be sent out -// but can also be used to instruct loopy to update its internal state. -// It shouldn't be confused with an HTTP2 frame, although some of the control frames -// like dataFrame and headerFrame do go out on wire as HTTP2 frames. -type controlBuffer struct { - ch chan struct{} - done <-chan struct{} - mu sync.Mutex - consumerWaiting bool - list *itemList - err error -} - -func newControlBuffer(done <-chan struct{}) *controlBuffer { - return &controlBuffer{ - ch: make(chan struct{}, 1), - list: &itemList{}, - done: done, - } -} - -func (c *controlBuffer) put(it interface{}) error { - _, err := c.executeAndPut(nil, it) - return err -} - -func (c *controlBuffer) executeAndPut(f func(it interface{}) bool, it interface{}) (bool, error) { - var wakeUp bool - c.mu.Lock() - if c.err != nil { - c.mu.Unlock() - return false, c.err - } - if f != nil { - if !f(it) { // f wasn't successful - c.mu.Unlock() - return false, nil - } - } - if c.consumerWaiting { - wakeUp = true - c.consumerWaiting = false - } - c.list.enqueue(it) - c.mu.Unlock() - if wakeUp { - select { - case c.ch <- struct{}{}: - default: - } - } - return true, nil -} - -// Note argument f should never be nil. -func (c *controlBuffer) execute(f func(it interface{}) bool, it interface{}) (bool, error) { - c.mu.Lock() - if c.err != nil { - c.mu.Unlock() - return false, c.err - } - if !f(it) { // f wasn't successful - c.mu.Unlock() - return false, nil - } - c.mu.Unlock() - return true, nil -} - -func (c *controlBuffer) get(block bool) (interface{}, error) { - for { - c.mu.Lock() - if c.err != nil { - c.mu.Unlock() - return nil, c.err - } - if !c.list.isEmpty() { - h := c.list.dequeue() - c.mu.Unlock() - return h, nil - } - if !block { - c.mu.Unlock() - return nil, nil - } - c.consumerWaiting = true - c.mu.Unlock() - select { - case <-c.ch: - case <-c.done: - c.finish() - return nil, ErrConnClosing - } - } -} - -func (c *controlBuffer) finish() { - c.mu.Lock() - if c.err != nil { - c.mu.Unlock() - return - } - c.err = ErrConnClosing - // There may be headers for streams in the control buffer. - // These streams need to be cleaned out since the transport - // is still not aware of these yet. - for head := c.list.dequeueAll(); head != nil; head = head.next { - hdr, ok := head.it.(*headerFrame) - if !ok { - continue - } - if hdr.onOrphaned != nil { // It will be nil on the server-side. - hdr.onOrphaned(ErrConnClosing) - } - } - c.mu.Unlock() -} - -type side int - -const ( - clientSide side = iota - serverSide -) - -// Loopy receives frames from the control buffer. -// Each frame is handled individually; most of the work done by loopy goes -// into handling data frames. Loopy maintains a queue of active streams, and each -// stream maintains a queue of data frames; as loopy receives data frames -// it gets added to the queue of the relevant stream. -// Loopy goes over this list of active streams by processing one node every iteration, -// thereby closely resemebling to a round-robin scheduling over all streams. While -// processing a stream, loopy writes out data bytes from this stream capped by the min -// of http2MaxFrameLen, connection-level flow control and stream-level flow control. -type loopyWriter struct { - side side - cbuf *controlBuffer - sendQuota uint32 - oiws uint32 // outbound initial window size. - // estdStreams is map of all established streams that are not cleaned-up yet. - // On client-side, this is all streams whose headers were sent out. - // On server-side, this is all streams whose headers were received. - estdStreams map[uint32]*outStream // Established streams. - // activeStreams is a linked-list of all streams that have data to send and some - // stream-level flow control quota. - // Each of these streams internally have a list of data items(and perhaps trailers - // on the server-side) to be sent out. - activeStreams *outStreamList - framer *framer - hBuf *bytes.Buffer // The buffer for HPACK encoding. - hEnc *hpack.Encoder // HPACK encoder. - bdpEst *bdpEstimator - draining bool - - // Side-specific handlers - ssGoAwayHandler func(*goAway) (bool, error) -} - -func newLoopyWriter(s side, fr *framer, cbuf *controlBuffer, bdpEst *bdpEstimator) *loopyWriter { - var buf bytes.Buffer - l := &loopyWriter{ - side: s, - cbuf: cbuf, - sendQuota: defaultWindowSize, - oiws: defaultWindowSize, - estdStreams: make(map[uint32]*outStream), - activeStreams: newOutStreamList(), - framer: fr, - hBuf: &buf, - hEnc: hpack.NewEncoder(&buf), - bdpEst: bdpEst, - } - return l -} - -const minBatchSize = 1000 - -// run should be run in a separate goroutine. -// It reads control frames from controlBuf and processes them by: -// 1. Updating loopy's internal state, or/and -// 2. Writing out HTTP2 frames on the wire. -// -// Loopy keeps all active streams with data to send in a linked-list. -// All streams in the activeStreams linked-list must have both: -// 1. Data to send, and -// 2. Stream level flow control quota available. -// -// In each iteration of run loop, other than processing the incoming control -// frame, loopy calls processData, which processes one node from the activeStreams linked-list. -// This results in writing of HTTP2 frames into an underlying write buffer. -// When there's no more control frames to read from controlBuf, loopy flushes the write buffer. -// As an optimization, to increase the batch size for each flush, loopy yields the processor, once -// if the batch size is too low to give stream goroutines a chance to fill it up. -func (l *loopyWriter) run() (err error) { - defer func() { - if err == ErrConnClosing { - // Don't log ErrConnClosing as error since it happens - // 1. When the connection is closed by some other known issue. - // 2. User closed the connection. - // 3. A graceful close of connection. - infof("transport: loopyWriter.run returning. %v", err) - err = nil - } - }() - for { - it, err := l.cbuf.get(true) - if err != nil { - return err - } - if err = l.handle(it); err != nil { - return err - } - if _, err = l.processData(); err != nil { - return err - } - gosched := true - hasdata: - for { - it, err := l.cbuf.get(false) - if err != nil { - return err - } - if it != nil { - if err = l.handle(it); err != nil { - return err - } - if _, err = l.processData(); err != nil { - return err - } - continue hasdata - } - isEmpty, err := l.processData() - if err != nil { - return err - } - if !isEmpty { - continue hasdata - } - if gosched { - gosched = false - if l.framer.writer.offset < minBatchSize { - runtime.Gosched() - continue hasdata - } - } - l.framer.writer.Flush() - break hasdata - - } - } -} - -func (l *loopyWriter) outgoingWindowUpdateHandler(w *outgoingWindowUpdate) error { - return l.framer.fr.WriteWindowUpdate(w.streamID, w.increment) -} - -func (l *loopyWriter) incomingWindowUpdateHandler(w *incomingWindowUpdate) error { - // Otherwise update the quota. - if w.streamID == 0 { - l.sendQuota += w.increment - return nil - } - // Find the stream and update it. - if str, ok := l.estdStreams[w.streamID]; ok { - str.bytesOutStanding -= int(w.increment) - if strQuota := int(l.oiws) - str.bytesOutStanding; strQuota > 0 && str.state == waitingOnStreamQuota { - str.state = active - l.activeStreams.enqueue(str) - return nil - } - } - return nil -} - -func (l *loopyWriter) outgoingSettingsHandler(s *outgoingSettings) error { - return l.framer.fr.WriteSettings(s.ss...) -} - -func (l *loopyWriter) incomingSettingsHandler(s *incomingSettings) error { - if err := l.applySettings(s.ss); err != nil { - return err - } - return l.framer.fr.WriteSettingsAck() -} - -func (l *loopyWriter) registerStreamHandler(h *registerStream) error { - str := &outStream{ - id: h.streamID, - state: empty, - itl: &itemList{}, - wq: h.wq, - } - l.estdStreams[h.streamID] = str - return nil -} - -func (l *loopyWriter) headerHandler(h *headerFrame) error { - if l.side == serverSide { - str, ok := l.estdStreams[h.streamID] - if !ok { - warningf("transport: loopy doesn't recognize the stream: %d", h.streamID) - return nil - } - // Case 1.A: Server is responding back with headers. - if !h.endStream { - return l.writeHeader(h.streamID, h.endStream, h.hf, h.onWrite) - } - // else: Case 1.B: Server wants to close stream. - - if str.state != empty { // either active or waiting on stream quota. - // add it str's list of items. - str.itl.enqueue(h) - return nil - } - if err := l.writeHeader(h.streamID, h.endStream, h.hf, h.onWrite); err != nil { - return err - } - return l.cleanupStreamHandler(h.cleanup) - } - // Case 2: Client wants to originate stream. - str := &outStream{ - id: h.streamID, - state: empty, - itl: &itemList{}, - wq: h.wq, - } - str.itl.enqueue(h) - return l.originateStream(str) -} - -func (l *loopyWriter) originateStream(str *outStream) error { - hdr := str.itl.dequeue().(*headerFrame) - sendPing, err := hdr.initStream(str.id) - if err != nil { - if err == ErrConnClosing { - return err - } - // Other errors(errStreamDrain) need not close transport. - return nil - } - if err = l.writeHeader(str.id, hdr.endStream, hdr.hf, hdr.onWrite); err != nil { - return err - } - l.estdStreams[str.id] = str - if sendPing { - return l.pingHandler(&ping{data: [8]byte{}}) - } - return nil -} - -func (l *loopyWriter) writeHeader(streamID uint32, endStream bool, hf []hpack.HeaderField, onWrite func()) error { - if onWrite != nil { - onWrite() - } - l.hBuf.Reset() - for _, f := range hf { - if err := l.hEnc.WriteField(f); err != nil { - warningf("transport: loopyWriter.writeHeader encountered error while encoding headers:", err) - } - } - var ( - err error - endHeaders, first bool - ) - first = true - for !endHeaders { - size := l.hBuf.Len() - if size > http2MaxFrameLen { - size = http2MaxFrameLen - } else { - endHeaders = true - } - if first { - first = false - err = l.framer.fr.WriteHeaders(http2.HeadersFrameParam{ - StreamID: streamID, - BlockFragment: l.hBuf.Next(size), - EndStream: endStream, - EndHeaders: endHeaders, - }) - } else { - err = l.framer.fr.WriteContinuation( - streamID, - endHeaders, - l.hBuf.Next(size), - ) - } - if err != nil { - return err - } - } - return nil -} - -func (l *loopyWriter) preprocessData(df *dataFrame) error { - str, ok := l.estdStreams[df.streamID] - if !ok { - return nil - } - // If we got data for a stream it means that - // stream was originated and the headers were sent out. - str.itl.enqueue(df) - if str.state == empty { - str.state = active - l.activeStreams.enqueue(str) - } - return nil -} - -func (l *loopyWriter) pingHandler(p *ping) error { - if !p.ack { - l.bdpEst.timesnap(p.data) - } - return l.framer.fr.WritePing(p.ack, p.data) - -} - -func (l *loopyWriter) outFlowControlSizeRequestHandler(o *outFlowControlSizeRequest) error { - o.resp <- l.sendQuota - return nil -} - -func (l *loopyWriter) cleanupStreamHandler(c *cleanupStream) error { - c.onWrite() - if str, ok := l.estdStreams[c.streamID]; ok { - // On the server side it could be a trailers-only response or - // a RST_STREAM before stream initialization thus the stream might - // not be established yet. - delete(l.estdStreams, c.streamID) - str.deleteSelf() - } - if c.rst { // If RST_STREAM needs to be sent. - if err := l.framer.fr.WriteRSTStream(c.streamID, c.rstCode); err != nil { - return err - } - } - if l.side == clientSide && l.draining && len(l.estdStreams) == 0 { - return ErrConnClosing - } - return nil -} - -func (l *loopyWriter) incomingGoAwayHandler(*incomingGoAway) error { - if l.side == clientSide { - l.draining = true - if len(l.estdStreams) == 0 { - return ErrConnClosing - } - } - return nil -} - -func (l *loopyWriter) goAwayHandler(g *goAway) error { - // Handling of outgoing GoAway is very specific to side. - if l.ssGoAwayHandler != nil { - draining, err := l.ssGoAwayHandler(g) - if err != nil { - return err - } - l.draining = draining - } - return nil -} - -func (l *loopyWriter) handle(i interface{}) error { - switch i := i.(type) { - case *incomingWindowUpdate: - return l.incomingWindowUpdateHandler(i) - case *outgoingWindowUpdate: - return l.outgoingWindowUpdateHandler(i) - case *incomingSettings: - return l.incomingSettingsHandler(i) - case *outgoingSettings: - return l.outgoingSettingsHandler(i) - case *headerFrame: - return l.headerHandler(i) - case *registerStream: - return l.registerStreamHandler(i) - case *cleanupStream: - return l.cleanupStreamHandler(i) - case *incomingGoAway: - return l.incomingGoAwayHandler(i) - case *dataFrame: - return l.preprocessData(i) - case *ping: - return l.pingHandler(i) - case *goAway: - return l.goAwayHandler(i) - case *outFlowControlSizeRequest: - return l.outFlowControlSizeRequestHandler(i) - default: - return fmt.Errorf("transport: unknown control message type %T", i) - } -} - -func (l *loopyWriter) applySettings(ss []http2.Setting) error { - for _, s := range ss { - switch s.ID { - case http2.SettingInitialWindowSize: - o := l.oiws - l.oiws = s.Val - if o < l.oiws { - // If the new limit is greater make all depleted streams active. - for _, stream := range l.estdStreams { - if stream.state == waitingOnStreamQuota { - stream.state = active - l.activeStreams.enqueue(stream) - } - } - } - case http2.SettingHeaderTableSize: - updateHeaderTblSize(l.hEnc, s.Val) - } - } - return nil -} - -// processData removes the first stream from active streams, writes out at most 16KB -// of its data and then puts it at the end of activeStreams if there's still more data -// to be sent and stream has some stream-level flow control. -func (l *loopyWriter) processData() (bool, error) { - if l.sendQuota == 0 { - return true, nil - } - str := l.activeStreams.dequeue() // Remove the first stream. - if str == nil { - return true, nil - } - dataItem := str.itl.peek().(*dataFrame) // Peek at the first data item this stream. - // A data item is represented by a dataFrame, since it later translates into - // multiple HTTP2 data frames. - // Every dataFrame has two buffers; h that keeps grpc-message header and d that is acutal data. - // As an optimization to keep wire traffic low, data from d is copied to h to make as big as the - // maximum possilbe HTTP2 frame size. - - if len(dataItem.h) == 0 && len(dataItem.d) == 0 { // Empty data frame - // Client sends out empty data frame with endStream = true - if err := l.framer.fr.WriteData(dataItem.streamID, dataItem.endStream, nil); err != nil { - return false, err - } - str.itl.dequeue() // remove the empty data item from stream - if str.itl.isEmpty() { - str.state = empty - } else if trailer, ok := str.itl.peek().(*headerFrame); ok { // the next item is trailers. - if err := l.writeHeader(trailer.streamID, trailer.endStream, trailer.hf, trailer.onWrite); err != nil { - return false, err - } - if err := l.cleanupStreamHandler(trailer.cleanup); err != nil { - return false, nil - } - } else { - l.activeStreams.enqueue(str) - } - return false, nil - } - var ( - idx int - buf []byte - ) - if len(dataItem.h) != 0 { // data header has not been written out yet. - buf = dataItem.h - } else { - idx = 1 - buf = dataItem.d - } - size := http2MaxFrameLen - if len(buf) < size { - size = len(buf) - } - if strQuota := int(l.oiws) - str.bytesOutStanding; strQuota <= 0 { // stream-level flow control. - str.state = waitingOnStreamQuota - return false, nil - } else if strQuota < size { - size = strQuota - } - - if l.sendQuota < uint32(size) { // connection-level flow control. - size = int(l.sendQuota) - } - // Now that outgoing flow controls are checked we can replenish str's write quota - str.wq.replenish(size) - var endStream bool - // If this is the last data message on this stream and all of it can be written in this iteration. - if dataItem.endStream && size == len(buf) { - // buf contains either data or it contains header but data is empty. - if idx == 1 || len(dataItem.d) == 0 { - endStream = true - } - } - if dataItem.onEachWrite != nil { - dataItem.onEachWrite() - } - if err := l.framer.fr.WriteData(dataItem.streamID, endStream, buf[:size]); err != nil { - return false, err - } - buf = buf[size:] - str.bytesOutStanding += size - l.sendQuota -= uint32(size) - if idx == 0 { - dataItem.h = buf - } else { - dataItem.d = buf - } - - if len(dataItem.h) == 0 && len(dataItem.d) == 0 { // All the data from that message was written out. - str.itl.dequeue() - } - if str.itl.isEmpty() { - str.state = empty - } else if trailer, ok := str.itl.peek().(*headerFrame); ok { // The next item is trailers. - if err := l.writeHeader(trailer.streamID, trailer.endStream, trailer.hf, trailer.onWrite); err != nil { - return false, err - } - if err := l.cleanupStreamHandler(trailer.cleanup); err != nil { - return false, err - } - } else if int(l.oiws)-str.bytesOutStanding <= 0 { // Ran out of stream quota. - str.state = waitingOnStreamQuota - } else { // Otherwise add it back to the list of active streams. - l.activeStreams.enqueue(str) - } - return false, nil -} |