107 lines
2.3 KiB
Go
107 lines
2.3 KiB
Go
|
// Copyright 2019 The gVisor 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 flipcall
|
||
|
|
||
|
import (
|
||
|
"bytes"
|
||
|
"fmt"
|
||
|
)
|
||
|
|
||
|
func Example() {
|
||
|
const (
|
||
|
reqPrefix = "request "
|
||
|
respPrefix = "response "
|
||
|
count = 3
|
||
|
maxMessageLen = len(respPrefix) + 1 // 1 digit
|
||
|
)
|
||
|
|
||
|
pwa, err := NewPacketWindowAllocator()
|
||
|
if err != nil {
|
||
|
panic(err)
|
||
|
}
|
||
|
defer pwa.Destroy()
|
||
|
pwd, err := pwa.Allocate(PacketWindowLengthForDataCap(uint32(maxMessageLen)))
|
||
|
if err != nil {
|
||
|
panic(err)
|
||
|
}
|
||
|
clientEP, err := NewEndpoint(ControlModeFutex, pwd)
|
||
|
if err != nil {
|
||
|
panic(err)
|
||
|
}
|
||
|
defer clientEP.Destroy()
|
||
|
serverEP, err := NewEndpoint(ControlModeFutex, pwd)
|
||
|
if err != nil {
|
||
|
panic(err)
|
||
|
}
|
||
|
defer serverEP.Destroy()
|
||
|
|
||
|
serverDone := make(chan struct{})
|
||
|
go func() {
|
||
|
defer func() { serverDone <- struct{}{} }()
|
||
|
i := 0
|
||
|
var buf bytes.Buffer
|
||
|
// wait for first request
|
||
|
n, err := serverEP.RecvFirst()
|
||
|
if err != nil {
|
||
|
return
|
||
|
}
|
||
|
for {
|
||
|
// read request
|
||
|
buf.Reset()
|
||
|
buf.Write(serverEP.Data()[:n])
|
||
|
fmt.Println(buf.String())
|
||
|
// write response
|
||
|
buf.Reset()
|
||
|
fmt.Fprintf(&buf, "%s%d", respPrefix, i)
|
||
|
copy(serverEP.Data(), buf.Bytes())
|
||
|
// send response and wait for next request
|
||
|
n, err = serverEP.SendRecv(uint32(buf.Len()))
|
||
|
if err != nil {
|
||
|
return
|
||
|
}
|
||
|
i++
|
||
|
}
|
||
|
}()
|
||
|
defer func() {
|
||
|
serverEP.Shutdown()
|
||
|
<-serverDone
|
||
|
}()
|
||
|
|
||
|
var buf bytes.Buffer
|
||
|
for i := 0; i < count; i++ {
|
||
|
// write request
|
||
|
buf.Reset()
|
||
|
fmt.Fprintf(&buf, "%s%d", reqPrefix, i)
|
||
|
copy(clientEP.Data(), buf.Bytes())
|
||
|
// send request and wait for response
|
||
|
n, err := clientEP.SendRecv(uint32(buf.Len()))
|
||
|
if err != nil {
|
||
|
panic(err)
|
||
|
}
|
||
|
// read response
|
||
|
buf.Reset()
|
||
|
buf.Write(clientEP.Data()[:n])
|
||
|
fmt.Println(buf.String())
|
||
|
}
|
||
|
|
||
|
// Output:
|
||
|
// request 0
|
||
|
// response 0
|
||
|
// request 1
|
||
|
// response 1
|
||
|
// request 2
|
||
|
// response 2
|
||
|
}
|