Merge pull request #110 from basecamp/exit-code

Return correct exit code when process signalled

Author: kevinmcconnell

internal/upstream_process.go

@@ -36,12 +36,7 @@ func (p *UpstreamProcess) Run() (int, error) {
 	go p.handleSignals()
 	err = p.cmd.Wait()
 
-	var exitErr *exec.ExitError
-	if errors.As(err, &exitErr) {
-		return exitErr.ExitCode(), nil
-	}
-
-	return 0, err
+	return p.handleExitCode(err)
 }
 
 func (p *UpstreamProcess) Signal(sig os.Signal) error {
@@ -56,3 +51,17 @@ func (p *UpstreamProcess) handleSignals() {
 	slog.Info("Relaying signal to upstream process", "signal", sig.String())
 	_ = p.Signal(sig)
 }
+
+func (p *UpstreamProcess) handleExitCode(err error) (int, error) {
+	var exitErr *exec.ExitError
+	if errors.As(err, &exitErr) {
+		if status, ok := exitErr.Sys().(syscall.WaitStatus); ok {
+			if status.Signaled() {
+				return 128 + int(status.Signal()), nil
+			}
+		}
+		return exitErr.ExitCode(), nil
+	}
+
+	return 0, err
+}

internal/upstream_process_test.go

@@ -19,17 +19,20 @@ func TestUpstreamProcess(t *testing.T) {
 	t.Run("signal a process to stop it", func(t *testing.T) {
 		var exitCode int
 		var err error
+		done := make(chan struct{})
 
 		p := NewUpstreamProcess("sleep", "10")
 
 		go func() {
 			exitCode, err = p.Run()
+			close(done)
 		}()
 
 		<-p.Started
 		assert.NoError(t, p.Signal(syscall.SIGTERM))
+		<-done
 
 		assert.NoError(t, err)
-		assert.Equal(t, 0, exitCode)
+		assert.Equal(t, 128+int(syscall.SIGTERM), exitCode)
 	})
 }