Go1.7.3一个收发消息的小接口

来源：互联网发布：淘宝第三方提供服务编辑：程序博客网时间：2024/06/06 10:50

package transportimport (    "encoding/binary"    "errors"    "io"    "math"    "sync")const (    sizeLen = 5 //设置消息多少字节大小,1<<4*8-1长度,最后一个字节用来做消息分割的,防止恶意链接)var (    ErrLength = errors.New("message too large")    ErrHeader = errors.New("message head error"))//添加数据头并发送func SedMsg(w io.Writer, p []byte) error {    msglen := len(p)    if msglen > math.MaxUint32 {        return ErrLength    }    var buf = make([]byte, sizeLen+msglen)    binary.BigEndian.PutUint32(buf, uint32(msglen))    copy(buf[sizeLen:], p)    _, err := w.Write(buf)    return err}//从数据流中根据头长度读取完整的消息func RcvMsg(r io.Reader, lock sync.Locker) ([]byte, error) {    lock.Lock()    defer lock.Unlock()    var header [sizeLen]byte    if _, err := io.ReadFull(r, header[:]); err != nil {        return nil, err    }    if header[sizeLen-1] == 0 {        length := binary.BigEndian.Uint32(header[:])        if length == 0 {            return nil, nil        }        msg := make([]byte, int(length))        if _, err := io.ReadFull(r, msg); err != nil {            if err == io.EOF {                err = io.ErrUnexpectedEOF            }            msg = msg[:0]            return nil, err        }        return msg, nil    }    return nil, ErrHeader}

1 0