ceph-csi/e2e/vendor/github.com/gorilla/websocket/prepared.go
Niels de Vos f87d06ed85 build: move e2e dependencies into e2e/go.mod
Several packages are only used while running the e2e suite. These
packages are less important to update, as the they can not influence the
final executable that is part of the Ceph-CSI container-image.

By moving these dependencies out of the main Ceph-CSI go.mod, it is
easier to identify if a reported CVE affects Ceph-CSI, or only the
testing (like most of the Kubernetes CVEs).

Signed-off-by: Niels de Vos <ndevos@ibm.com>
2025-03-04 17:43:49 +01:00

103 lines
2.9 KiB
Go

// 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 struct{}, 1)
mu <- struct{}{}
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 }