spongy

readwritecloserwrapper.go

 1package main
 2
 3import (
 4	"io"
 5	"os/exec"
 6	"log"
 7)
 8
 9type ReadWriteCloserWrapper struct {
10	Reader io.ReadCloser
11	Writer io.WriteCloser
12	cmd *exec.Cmd
13}
14
15func NewReadWriteCloseWrapper(r io.ReadCloser, w io.WriteCloser) *ReadWriteCloserWrapper {
16	return &ReadWriteCloserWrapper{r, w, nil}
17}
18
19func (w *ReadWriteCloserWrapper) Close() (error) {
20	err1 := w.Reader.Close()
21	err2 := w.Writer.Close()
22	if w.cmd != nil{
23		w.cmd.Wait()
24	}
25	
26	switch {
27	case err1 != nil:
28		return err1
29	case err2 != nil:
30		return err2
31	}
32	return nil
33}
34
35func (w *ReadWriteCloserWrapper) Read(p []byte) (n int, err error) {
36	n, err = w.Reader.Read(p)
37	return
38}
39
40func (w *ReadWriteCloserWrapper) Write(p []byte) (n int, err error) {
41	n, err = w.Writer.Write(p)
42	return
43}
44
45func StartStdioProcess(name string, args []string) (w *ReadWriteCloserWrapper, err error) {
46	w = new(ReadWriteCloserWrapper)
47
48	cmd := exec.Command(name, args...)
49	
50	if cmd == nil {
51		log.Fatalf("Can't run command: %v %v", name, args)
52	}
53	
54	w.Reader, err = cmd.StdoutPipe()
55	if err != nil {
56		return nil, err
57	}
58	
59	w.Writer, err = cmd.StdinPipe()
60	if err != nil {
61		w.Reader.Close()
62		return nil, err
63	}
64	
65	if err = cmd.Start(); err != nil {
66		w.Reader.Close()
67		w.Writer.Close()
68		return nil, err
69	}
70	
71	w.cmd = cmd
72	
73	return 
74}