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