Use chan only to notify command is done to avoid race condition

Signed-off-by: Shinnosuke Sawada-Dazai <[email protected]>

pkg/app/launcher/cmd/launcher/binary.go

@@ -21,6 +21,7 @@ import (
  "os"
  "os/exec"
  "path/filepath"
+ "sync/atomic"
  "syscall"
  "time"
 
@@ -29,7 +30,8 @@ import (
 
 type command struct {
  cmd *exec.Cmd
- stoppedCh chan error
+ stoppedCh chan struct{}
+ result atomic.Pointer[error]
 }
 
 func (c *command) IsRunning() bool {
@@ -50,9 +52,16 @@ func (c *command) GracefulStop(period time.Duration) error {
  select {
  case <-timer.C:
  c.cmd.Process.Kill()
- return <-c.stoppedCh
- case err := <-c.stoppedCh:
- return err
+ <-c.stoppedCh
+ if perr := c.result.Load(); perr != nil {
+ return *perr
+ }
+ return nil
+ case <-c.stoppedCh:
+ if perr := c.result.Load(); perr != nil {
+ return *perr
+ }
+ return nil
  }
 }
 
@@ -68,11 +77,12 @@ func runBinary(execPath string, args []string) (*command, error) {
 
  c := &command{
  cmd: cmd,
- stoppedCh: make(chan error, 1),
+ stoppedCh: make(chan struct{}),
+ result: atomic.Pointer[error]{},
  }
  go func() {
  err := cmd.Wait()
- c.stoppedCh <- err
+ c.result.Store(&err)
  close(c.stoppedCh)
  }()