From 2f0b35e3c25bc4394f3288e1baa77d250cb510ed Mon Sep 17 00:00:00 2001 From: Jordan Date: Thu, 10 Feb 2022 19:10:54 -0700 Subject: misc: go mod vendor --- vendor/github.com/gorilla/websocket/prepared.go | 102 ++++++++++++++++++++++++ 1 file changed, 102 insertions(+) create mode 100644 vendor/github.com/gorilla/websocket/prepared.go (limited to 'vendor/github.com/gorilla/websocket/prepared.go') diff --git a/vendor/github.com/gorilla/websocket/prepared.go b/vendor/github.com/gorilla/websocket/prepared.go new file mode 100644 index 0000000..74ec565 --- /dev/null +++ b/vendor/github.com/gorilla/websocket/prepared.go @@ -0,0 +1,102 @@ +// Copyright 2017 The Gorilla WebSocket 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 websocket + +import ( + "bytes" + "net" + "sync" + "time" +) + +// PreparedMessage caches on the wire representations of a message payload. +// Use PreparedMessage to efficiently send a message payload to multiple +// connections. PreparedMessage is especially useful when compression is used +// because the CPU and memory expensive compression operation can be executed +// once for a given set of compression options. +type PreparedMessage struct { + messageType int + data []byte + mu sync.Mutex + frames map[prepareKey]*preparedFrame +} + +// prepareKey defines a unique set of options to cache prepared frames in PreparedMessage. +type prepareKey struct { + isServer bool + compress bool + compressionLevel int +} + +// preparedFrame contains data in wire representation. +type preparedFrame struct { + once sync.Once + data []byte +} + +// NewPreparedMessage returns an initialized PreparedMessage. You can then send +// it to connection using WritePreparedMessage method. Valid wire +// representation will be calculated lazily only once for a set of current +// connection options. +func NewPreparedMessage(messageType int, data []byte) (*PreparedMessage, error) { + pm := &PreparedMessage{ + messageType: messageType, + frames: make(map[prepareKey]*preparedFrame), + data: data, + } + + // Prepare a plain server frame. + _, frameData, err := pm.frame(prepareKey{isServer: true, compress: false}) + if err != nil { + return nil, err + } + + // To protect against caller modifying the data argument, remember the data + // copied to the plain server frame. + pm.data = frameData[len(frameData)-len(data):] + return pm, nil +} + +func (pm *PreparedMessage) frame(key prepareKey) (int, []byte, error) { + pm.mu.Lock() + frame, ok := pm.frames[key] + if !ok { + frame = &preparedFrame{} + pm.frames[key] = frame + } + pm.mu.Unlock() + + var err error + frame.once.Do(func() { + // Prepare a frame using a 'fake' connection. + // TODO: Refactor code in conn.go to allow more direct construction of + // the frame. + mu := make(chan bool, 1) + mu <- true + var nc prepareConn + c := &Conn{ + conn: &nc, + mu: mu, + isServer: key.isServer, + compressionLevel: key.compressionLevel, + enableWriteCompression: true, + writeBuf: make([]byte, defaultWriteBufferSize+maxFrameHeaderSize), + } + if key.compress { + c.newCompressionWriter = compressNoContextTakeover + } + err = c.WriteMessage(pm.messageType, pm.data) + frame.data = nc.buf.Bytes() + }) + return pm.messageType, frame.data, err +} + +type prepareConn struct { + buf bytes.Buffer + net.Conn +} + +func (pc *prepareConn) Write(p []byte) (int, error) { return pc.buf.Write(p) } +func (pc *prepareConn) SetWriteDeadline(t time.Time) error { return nil } -- cgit v1.2.3-54-g00ecf