Fix running backchannel exec without start #1080

pkg/stdin/client.go

@@ -1,15 +1,13 @@
 package stdin
 
 import (
-	"io"
 	"os/exec"
 
 	"github.com/AlexxIT/go2rtc/pkg/core"
 )
 
 type Client struct {
-	cmd  *exec.Cmd
-	pipe io.WriteCloser
+	cmd *exec.Cmd
 
 	medias []*core.Media
 	sender *core.Sender
@@ -17,14 +15,8 @@ type Client struct {
 }
 
 func NewClient(cmd *exec.Cmd) (*Client, error) {
-	pipe, err := PipeCloser(cmd)
-	if err != nil {
-		return nil, err
-	}
-
 	c := &Client{
-		pipe: pipe,
-		cmd:  cmd,
+		cmd: cmd,
 		medias: []*core.Media{
 			{
 				Kind:      core.KindAudio,

pkg/stdin/consumer.go

@@ -2,6 +2,7 @@ package stdin
 
 import (
 	"encoding/json"
+	"errors"
 
 	"github.com/AlexxIT/go2rtc/pkg/core"
 	"github.com/pion/rtp"
@@ -17,9 +18,14 @@ func (c *Client) GetTrack(media *core.Media, codec *core.Codec) (*core.Receiver,
 
 func (c *Client) AddTrack(media *core.Media, _ *core.Codec, track *core.Receiver) error {
 	if c.sender == nil {
+		stdin, err := c.cmd.StdinPipe()
+		if err != nil {
+			return err
+		}
+
 		c.sender = core.NewSender(media, track.Codec)
 		c.sender.Handler = func(packet *rtp.Packet) {
-			_, _ = c.pipe.Write(packet.Payload)
+			_, _ = stdin.Write(packet.Payload)
 			c.send += len(packet.Payload)
 		}
 	}
@@ -36,7 +42,10 @@ func (c *Client) Stop() (err error) {
 	if c.sender != nil {
 		c.sender.Close()
 	}
-	return c.pipe.Close()
+	if c.cmd.Process == nil {
+		return nil
+	}
+	return errors.Join(c.cmd.Process.Kill(), c.cmd.Wait())
 }
 
 func (c *Client) MarshalJSON() ([]byte, error) {

pkg/stdin/pipe.go

@@ -1,26 +0,0 @@
-package stdin
-
-import (
-	"errors"
-	"io"
-	"os/exec"
-)
-
-type pipeCloser struct {
-	io.Writer
-	io.Closer
-	cmd *exec.Cmd
-}
-
-func PipeCloser(cmd *exec.Cmd) (io.WriteCloser, error) {
-	stdin, err := cmd.StdinPipe()
-	if err != nil {
-		return nil, err
-	}
-
-	return pipeCloser{stdin, stdin, cmd}, nil
-}
-
-func (p pipeCloser) Close() (err error) {
-	return errors.Join(p.Closer.Close(), p.cmd.Process.Kill(), p.cmd.Wait())
-}