go/rpc/conn.go

79 lines
1.2 KiB
Go

package rpc
import (
"encoding/binary"
"fmt"
"io"
"net"
)
type conn struct {
co net.Conn
}
func newConn(network, addr string) (*conn, error) {
c, err := net.Dial(network, addr)
if err != nil {
return nil, err
}
co := new(conn)
co.co = c
return co, nil
}
func (c *conn) Close() error {
return c.co.Close()
}
func (c *conn) Call(data []byte) ([]byte, error) {
if err := c.WriteMessage(data); err != nil {
return nil, err
}
if buf, err := c.ReadMessage(); err != nil {
return nil, err
} else {
return buf, nil
}
}
func (c *conn) WriteMessage(data []byte) error {
buf := make([]byte, 4+len(data))
binary.LittleEndian.PutUint32(buf[0:4], uint32(len(data)))
copy(buf[4:], data)
n, err := c.co.Write(buf)
if err != nil {
c.Close()
return err
} else if n != len(buf) {
c.Close()
return fmt.Errorf("write %d less than %d", n, len(buf))
}
return nil
}
func (c *conn) ReadMessage() ([]byte, error) {
l := make([]byte, 4)
_, err := io.ReadFull(c.co, l)
if err != nil {
c.Close()
return nil, err
}
length := binary.LittleEndian.Uint32(l)
data := make([]byte, length)
_, err = io.ReadFull(c.co, data)
if err != nil {
c.Close()
return nil, err
} else {
return data, nil
}
}