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-rw-r--r--kube2msb/src/vendor/golang.org/x/net/http2/writesched.go283
1 files changed, 0 insertions, 283 deletions
diff --git a/kube2msb/src/vendor/golang.org/x/net/http2/writesched.go b/kube2msb/src/vendor/golang.org/x/net/http2/writesched.go
deleted file mode 100644
index c24316c..0000000
--- a/kube2msb/src/vendor/golang.org/x/net/http2/writesched.go
+++ /dev/null
@@ -1,283 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package http2
-
-import "fmt"
-
-// frameWriteMsg is a request to write a frame.
-type frameWriteMsg struct {
- // write is the interface value that does the writing, once the
- // writeScheduler (below) has decided to select this frame
- // to write. The write functions are all defined in write.go.
- write writeFramer
-
- stream *stream // used for prioritization. nil for non-stream frames.
-
- // done, if non-nil, must be a buffered channel with space for
- // 1 message and is sent the return value from write (or an
- // earlier error) when the frame has been written.
- done chan error
-}
-
-// for debugging only:
-func (wm frameWriteMsg) String() string {
- var streamID uint32
- if wm.stream != nil {
- streamID = wm.stream.id
- }
- var des string
- if s, ok := wm.write.(fmt.Stringer); ok {
- des = s.String()
- } else {
- des = fmt.Sprintf("%T", wm.write)
- }
- return fmt.Sprintf("[frameWriteMsg stream=%d, ch=%v, type: %v]", streamID, wm.done != nil, des)
-}
-
-// writeScheduler tracks pending frames to write, priorities, and decides
-// the next one to use. It is not thread-safe.
-type writeScheduler struct {
- // zero are frames not associated with a specific stream.
- // They're sent before any stream-specific freams.
- zero writeQueue
-
- // maxFrameSize is the maximum size of a DATA frame
- // we'll write. Must be non-zero and between 16K-16M.
- maxFrameSize uint32
-
- // sq contains the stream-specific queues, keyed by stream ID.
- // when a stream is idle, it's deleted from the map.
- sq map[uint32]*writeQueue
-
- // canSend is a slice of memory that's reused between frame
- // scheduling decisions to hold the list of writeQueues (from sq)
- // which have enough flow control data to send. After canSend is
- // built, the best is selected.
- canSend []*writeQueue
-
- // pool of empty queues for reuse.
- queuePool []*writeQueue
-}
-
-func (ws *writeScheduler) putEmptyQueue(q *writeQueue) {
- if len(q.s) != 0 {
- panic("queue must be empty")
- }
- ws.queuePool = append(ws.queuePool, q)
-}
-
-func (ws *writeScheduler) getEmptyQueue() *writeQueue {
- ln := len(ws.queuePool)
- if ln == 0 {
- return new(writeQueue)
- }
- q := ws.queuePool[ln-1]
- ws.queuePool = ws.queuePool[:ln-1]
- return q
-}
-
-func (ws *writeScheduler) empty() bool { return ws.zero.empty() && len(ws.sq) == 0 }
-
-func (ws *writeScheduler) add(wm frameWriteMsg) {
- st := wm.stream
- if st == nil {
- ws.zero.push(wm)
- } else {
- ws.streamQueue(st.id).push(wm)
- }
-}
-
-func (ws *writeScheduler) streamQueue(streamID uint32) *writeQueue {
- if q, ok := ws.sq[streamID]; ok {
- return q
- }
- if ws.sq == nil {
- ws.sq = make(map[uint32]*writeQueue)
- }
- q := ws.getEmptyQueue()
- ws.sq[streamID] = q
- return q
-}
-
-// take returns the most important frame to write and removes it from the scheduler.
-// It is illegal to call this if the scheduler is empty or if there are no connection-level
-// flow control bytes available.
-func (ws *writeScheduler) take() (wm frameWriteMsg, ok bool) {
- if ws.maxFrameSize == 0 {
- panic("internal error: ws.maxFrameSize not initialized or invalid")
- }
-
- // If there any frames not associated with streams, prefer those first.
- // These are usually SETTINGS, etc.
- if !ws.zero.empty() {
- return ws.zero.shift(), true
- }
- if len(ws.sq) == 0 {
- return
- }
-
- // Next, prioritize frames on streams that aren't DATA frames (no cost).
- for id, q := range ws.sq {
- if q.firstIsNoCost() {
- return ws.takeFrom(id, q)
- }
- }
-
- // Now, all that remains are DATA frames with non-zero bytes to
- // send. So pick the best one.
- if len(ws.canSend) != 0 {
- panic("should be empty")
- }
- for _, q := range ws.sq {
- if n := ws.streamWritableBytes(q); n > 0 {
- ws.canSend = append(ws.canSend, q)
- }
- }
- if len(ws.canSend) == 0 {
- return
- }
- defer ws.zeroCanSend()
-
- // TODO: find the best queue
- q := ws.canSend[0]
-
- return ws.takeFrom(q.streamID(), q)
-}
-
-// zeroCanSend is defered from take.
-func (ws *writeScheduler) zeroCanSend() {
- for i := range ws.canSend {
- ws.canSend[i] = nil
- }
- ws.canSend = ws.canSend[:0]
-}
-
-// streamWritableBytes returns the number of DATA bytes we could write
-// from the given queue's stream, if this stream/queue were
-// selected. It is an error to call this if q's head isn't a
-// *writeData.
-func (ws *writeScheduler) streamWritableBytes(q *writeQueue) int32 {
- wm := q.head()
- ret := wm.stream.flow.available() // max we can write
- if ret == 0 {
- return 0
- }
- if int32(ws.maxFrameSize) < ret {
- ret = int32(ws.maxFrameSize)
- }
- if ret == 0 {
- panic("internal error: ws.maxFrameSize not initialized or invalid")
- }
- wd := wm.write.(*writeData)
- if len(wd.p) < int(ret) {
- ret = int32(len(wd.p))
- }
- return ret
-}
-
-func (ws *writeScheduler) takeFrom(id uint32, q *writeQueue) (wm frameWriteMsg, ok bool) {
- wm = q.head()
- // If the first item in this queue costs flow control tokens
- // and we don't have enough, write as much as we can.
- if wd, ok := wm.write.(*writeData); ok && len(wd.p) > 0 {
- allowed := wm.stream.flow.available() // max we can write
- if allowed == 0 {
- // No quota available. Caller can try the next stream.
- return frameWriteMsg{}, false
- }
- if int32(ws.maxFrameSize) < allowed {
- allowed = int32(ws.maxFrameSize)
- }
- // TODO: further restrict the allowed size, because even if
- // the peer says it's okay to write 16MB data frames, we might
- // want to write smaller ones to properly weight competing
- // streams' priorities.
-
- if len(wd.p) > int(allowed) {
- wm.stream.flow.take(allowed)
- chunk := wd.p[:allowed]
- wd.p = wd.p[allowed:]
- // Make up a new write message of a valid size, rather
- // than shifting one off the queue.
- return frameWriteMsg{
- stream: wm.stream,
- write: &writeData{
- streamID: wd.streamID,
- p: chunk,
- // even if the original had endStream set, there
- // arebytes remaining because len(wd.p) > allowed,
- // so we know endStream is false:
- endStream: false,
- },
- // our caller is blocking on the final DATA frame, not
- // these intermediates, so no need to wait:
- done: nil,
- }, true
- }
- wm.stream.flow.take(int32(len(wd.p)))
- }
-
- q.shift()
- if q.empty() {
- ws.putEmptyQueue(q)
- delete(ws.sq, id)
- }
- return wm, true
-}
-
-func (ws *writeScheduler) forgetStream(id uint32) {
- q, ok := ws.sq[id]
- if !ok {
- return
- }
- delete(ws.sq, id)
-
- // But keep it for others later.
- for i := range q.s {
- q.s[i] = frameWriteMsg{}
- }
- q.s = q.s[:0]
- ws.putEmptyQueue(q)
-}
-
-type writeQueue struct {
- s []frameWriteMsg
-}
-
-// streamID returns the stream ID for a non-empty stream-specific queue.
-func (q *writeQueue) streamID() uint32 { return q.s[0].stream.id }
-
-func (q *writeQueue) empty() bool { return len(q.s) == 0 }
-
-func (q *writeQueue) push(wm frameWriteMsg) {
- q.s = append(q.s, wm)
-}
-
-// head returns the next item that would be removed by shift.
-func (q *writeQueue) head() frameWriteMsg {
- if len(q.s) == 0 {
- panic("invalid use of queue")
- }
- return q.s[0]
-}
-
-func (q *writeQueue) shift() frameWriteMsg {
- if len(q.s) == 0 {
- panic("invalid use of queue")
- }
- wm := q.s[0]
- // TODO: less copy-happy queue.
- copy(q.s, q.s[1:])
- q.s[len(q.s)-1] = frameWriteMsg{}
- q.s = q.s[:len(q.s)-1]
- return wm
-}
-
-func (q *writeQueue) firstIsNoCost() bool {
- if df, ok := q.s[0].write.(*writeData); ok {
- return len(df.p) == 0
- }
- return true
-}