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migrate to go modules from vndr

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Signed-off-by: Tariq Ibrahim <tariq181290@gmail.com>
This commit is contained in:
Tariq Ibrahim 2019-06-05 15:40:29 -07:00
parent dcfe05ce6c
commit 5223c27422
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GPG key ID: DFC94E4A008B908A
503 changed files with 273730 additions and 9491 deletions
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429
vendor/golang.org/x/net/http2/writesched.go generated vendored
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@ -6,14 +6,53 @@ package http2
import "fmt"
// frameWriteMsg is a request to write a frame.
type frameWriteMsg struct {
// WriteScheduler is the interface implemented by HTTP/2 write schedulers.
// Methods are never called concurrently.
type WriteScheduler interface {
// OpenStream opens a new stream in the write scheduler.
// It is illegal to call this with streamID=0 or with a streamID that is
// already open -- the call may panic.
OpenStream(streamID uint32, options OpenStreamOptions)
// CloseStream closes a stream in the write scheduler. Any frames queued on
// this stream should be discarded. It is illegal to call this on a stream
// that is not open -- the call may panic.
CloseStream(streamID uint32)
// AdjustStream adjusts the priority of the given stream. This may be called
// on a stream that has not yet been opened or has been closed. Note that
// RFC 7540 allows PRIORITY frames to be sent on streams in any state. See:
// https://tools.ietf.org/html/rfc7540#section-5.1
AdjustStream(streamID uint32, priority PriorityParam)
// Push queues a frame in the scheduler. In most cases, this will not be
// called with wr.StreamID()!=0 unless that stream is currently open. The one
// exception is RST_STREAM frames, which may be sent on idle or closed streams.
Push(wr FrameWriteRequest)
// Pop dequeues the next frame to write. Returns false if no frames can
// be written. Frames with a given wr.StreamID() are Pop'd in the same
// order they are Push'd.
Pop() (wr FrameWriteRequest, ok bool)
}
// OpenStreamOptions specifies extra options for WriteScheduler.OpenStream.
type OpenStreamOptions struct {
// PusherID is zero if the stream was initiated by the client. Otherwise,
// PusherID names the stream that pushed the newly opened stream.
PusherID uint32
}
// FrameWriteRequest is a request to write a frame.
type FrameWriteRequest 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.
// WriteScheduler has selected 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.
// stream is the stream on which this frame will be written.
// nil for non-stream frames like PING and SETTINGS.
stream *stream
// done, if non-nil, must be a buffered channel with space for
// 1 message and is sent the return value from write (or an
@ -21,263 +60,183 @@ type frameWriteMsg struct {
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)
// StreamID returns the id of the stream this frame will be written to.
// 0 is used for non-stream frames such as PING and SETTINGS.
func (wr FrameWriteRequest) StreamID() uint32 {
if wr.stream == nil {
if se, ok := wr.write.(StreamError); ok {
// (*serverConn).resetStream doesn't set
// stream because it doesn't necessarily have
// one. So special case this type of write
// message.
return se.StreamID
}
}
// 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
return wr.stream.id
}
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)))
// DataSize returns the number of flow control bytes that must be consumed
// to write this entire frame. This is 0 for non-DATA frames.
func (wr FrameWriteRequest) DataSize() int {
if wd, ok := wr.write.(*writeData); ok {
return len(wd.p)
}
q.shift()
if q.empty() {
ws.putEmptyQueue(q)
delete(ws.sq, id)
}
return wm, true
return 0
}
func (ws *writeScheduler) forgetStream(id uint32) {
q, ok := ws.sq[id]
if !ok {
// Consume consumes min(n, available) bytes from this frame, where available
// is the number of flow control bytes available on the stream. Consume returns
// 0, 1, or 2 frames, where the integer return value gives the number of frames
// returned.
//
// If flow control prevents consuming any bytes, this returns (_, _, 0). If
// the entire frame was consumed, this returns (wr, _, 1). Otherwise, this
// returns (consumed, rest, 2), where 'consumed' contains the consumed bytes and
// 'rest' contains the remaining bytes. The consumed bytes are deducted from the
// underlying stream's flow control budget.
func (wr FrameWriteRequest) Consume(n int32) (FrameWriteRequest, FrameWriteRequest, int) {
var empty FrameWriteRequest
// Non-DATA frames are always consumed whole.
wd, ok := wr.write.(*writeData)
if !ok || len(wd.p) == 0 {
return wr, empty, 1
}
// Might need to split after applying limits.
allowed := wr.stream.flow.available()
if n < allowed {
allowed = n
}
if wr.stream.sc.maxFrameSize < allowed {
allowed = wr.stream.sc.maxFrameSize
}
if allowed <= 0 {
return empty, empty, 0
}
if len(wd.p) > int(allowed) {
wr.stream.flow.take(allowed)
consumed := FrameWriteRequest{
stream: wr.stream,
write: &writeData{
streamID: wd.streamID,
p: wd.p[:allowed],
// Even if the original had endStream set, there
// are bytes remaining because len(wd.p) > allowed,
// so we know endStream is false.
endStream: false,
},
// Our caller is blocking on the final DATA frame, not
// this intermediate frame, so no need to wait.
done: nil,
}
rest := FrameWriteRequest{
stream: wr.stream,
write: &writeData{
streamID: wd.streamID,
p: wd.p[allowed:],
endStream: wd.endStream,
},
done: wr.done,
}
return consumed, rest, 2
}
// The frame is consumed whole.
// NB: This cast cannot overflow because allowed is <= math.MaxInt32.
wr.stream.flow.take(int32(len(wd.p)))
return wr, empty, 1
}
// String is for debugging only.
func (wr FrameWriteRequest) String() string {
var des string
if s, ok := wr.write.(fmt.Stringer); ok {
des = s.String()
} else {
des = fmt.Sprintf("%T", wr.write)
}
return fmt.Sprintf("[FrameWriteRequest stream=%d, ch=%v, writer=%v]", wr.StreamID(), wr.done != nil, des)
}
// replyToWriter sends err to wr.done and panics if the send must block
// This does nothing if wr.done is nil.
func (wr *FrameWriteRequest) replyToWriter(err error) {
if wr.done == nil {
return
}
delete(ws.sq, id)
// But keep it for others later.
for i := range q.s {
q.s[i] = frameWriteMsg{}
select {
case wr.done <- err:
default:
panic(fmt.Sprintf("unbuffered done channel passed in for type %T", wr.write))
}
q.s = q.s[:0]
ws.putEmptyQueue(q)
wr.write = nil // prevent use (assume it's tainted after wr.done send)
}
// writeQueue is used by implementations of WriteScheduler.
type writeQueue struct {
s []frameWriteMsg
s []FrameWriteRequest
}
// 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)
func (q *writeQueue) push(wr FrameWriteRequest) {
q.s = append(q.s, wr)
}
// head returns the next item that would be removed by shift.
func (q *writeQueue) head() frameWriteMsg {
func (q *writeQueue) shift() FrameWriteRequest {
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]
wr := q.s[0]
// TODO: less copy-happy queue.
copy(q.s, q.s[1:])
q.s[len(q.s)-1] = frameWriteMsg{}
q.s[len(q.s)-1] = FrameWriteRequest{}
q.s = q.s[:len(q.s)-1]
return wm
return wr
}
func (q *writeQueue) firstIsNoCost() bool {
if df, ok := q.s[0].write.(*writeData); ok {
return len(df.p) == 0
// consume consumes up to n bytes from q.s[0]. If the frame is
// entirely consumed, it is removed from the queue. If the frame
// is partially consumed, the frame is kept with the consumed
// bytes removed. Returns true iff any bytes were consumed.
func (q *writeQueue) consume(n int32) (FrameWriteRequest, bool) {
if len(q.s) == 0 {
return FrameWriteRequest{}, false
}
return true
consumed, rest, numresult := q.s[0].Consume(n)
switch numresult {
case 0:
return FrameWriteRequest{}, false
case 1:
q.shift()
case 2:
q.s[0] = rest
}
return consumed, true
}
type writeQueuePool []*writeQueue
// put inserts an unused writeQueue into the pool.
func (p *writeQueuePool) put(q *writeQueue) {
for i := range q.s {
q.s[i] = FrameWriteRequest{}
}
q.s = q.s[:0]
*p = append(*p, q)
}
// get returns an empty writeQueue.
func (p *writeQueuePool) get() *writeQueue {
ln := len(*p)
if ln == 0 {
return new(writeQueue)
}
x := ln - 1
q := (*p)[x]
(*p)[x] = nil
*p = (*p)[:x]
return q
}