frp/models/msg/process.go

89 lines
1.8 KiB
Go

// Copyright 2016 fatedier, fatedier@gmail.com
//
// 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 msg
import (
"encoding/binary"
"fmt"
"io"
)
var (
MaxMsgLength int64 = 10240
)
func readMsg(c io.Reader) (typeByte byte, buffer []byte, err error) {
buffer = make([]byte, 1)
_, err = c.Read(buffer)
if err != nil {
return
}
typeByte = buffer[0]
if _, ok := TypeMap[typeByte]; !ok {
err = fmt.Errorf("Message type error")
return
}
var length int64
err = binary.Read(c, binary.BigEndian, &length)
if err != nil {
return
}
if length > MaxMsgLength {
err = fmt.Errorf("Message length exceed the limit")
return
}
buffer = make([]byte, length)
n, err := io.ReadFull(c, buffer)
if err != nil {
return
}
if int64(n) != length {
err = fmt.Errorf("Message format error")
}
return
}
func ReadMsg(c io.Reader) (msg Message, err error) {
typeByte, buffer, err := readMsg(c)
if err != nil {
return
}
return UnPack(typeByte, buffer)
}
func ReadMsgInto(c io.Reader, msg Message) (err error) {
_, buffer, err := readMsg(c)
if err != nil {
return
}
return UnPackInto(buffer, msg)
}
func WriteMsg(c io.Writer, msg interface{}) (err error) {
buffer, err := Pack(msg)
if err != nil {
return
}
if _, err = c.Write(buffer); err != nil {
return
}
return nil
}