ci: fix a race in TestExecIn and TestExecInTTY

Signed-off-by: lifubang <[email protected]>

Author: lifubang

libcontainer/integration/execin_test.go

@@ -30,16 +30,33 @@ func TestExecIn(t *testing.T) {
 	// Execute a first process in the container
 	stdinR, stdinW, err := os.Pipe()
 	ok(t, err)
+	stdoutR, stdoutW, err := os.Pipe()
+	ok(t, err)
+	defer stdinR.Close()  //nolint: errcheck
+	defer stdinW.Close()  //nolint: errcheck
+	defer stdoutR.Close() //nolint: errcheck
+	defer stdoutW.Close() //nolint: errcheck
+
+	ch := waitStdOut(stdoutR)
 	process := &libcontainer.Process{
-		Cwd:   "/",
-		Args:  []string{"cat"},
-		Env:   standardEnvironment,
-		Stdin: stdinR,
-		Init:  true,
+		Cwd:    "/",
+		Args:   []string{"cat", "/proc/self/cmdline", "-"},
+		Env:    standardEnvironment,
+		Stdin:  stdinR,
+		Stdout: stdoutW,
+		Init:   true,
 	}
 	err = container.Run(process)
-	_ = stdinR.Close()
-	defer stdinW.Close() //nolint: errcheck
+	defer func() {
+		stdinW.Write([]byte("hello"))
+		_ = stdinW.Close()
+		if _, err := process.Wait(); err != nil {
+			t.Log(err)
+		}
+	}()
+	ok(t, err)
+
+	err = <-ch
 	ok(t, err)
 
 	buffers := newStdBuffers()
@@ -55,8 +72,6 @@ func TestExecIn(t *testing.T) {
 	err = container.Run(ps)
 	ok(t, err)
 	waitProcess(ps, t)
-	_ = stdinW.Close()
-	waitProcess(process, t)
 
 	out := buffers.Stdout.String()
 	if !strings.Contains(out, "cat") || !strings.Contains(out, "ps") {
@@ -242,23 +257,35 @@ func TestExecInTTY(t *testing.T) {
 	// Execute a first process in the container
 	stdinR, stdinW, err := os.Pipe()
 	ok(t, err)
+	stdoutR, stdoutW, err := os.Pipe()
+	ok(t, err)
+	defer stdinR.Close()  //nolint: errcheck
+	defer stdinW.Close()  //nolint: errcheck
+	defer stdoutR.Close() //nolint: errcheck
+	defer stdoutW.Close() //nolint: errcheck
+
+	ch := waitStdOut(stdoutR)
 	process := &libcontainer.Process{
-		Cwd:   "/",
-		Args:  []string{"cat"},
-		Env:   standardEnvironment,
-		Stdin: stdinR,
-		Init:  true,
+		Cwd:    "/",
+		Args:   []string{"cat", "/proc/self/cmdline", "-"},
+		Env:    standardEnvironment,
+		Stdin:  stdinR,
+		Stdout: stdoutW,
+		Init:   true,
 	}
 	err = container.Run(process)
-	_ = stdinR.Close()
 	defer func() {
+		stdinW.Write([]byte("hello"))
 		_ = stdinW.Close()
 		if _, err := process.Wait(); err != nil {
 			t.Log(err)
 		}
 	}()
 	ok(t, err)
 
+	err = <-ch
+	ok(t, err)
+
 	ps := &libcontainer.Process{
 		Cwd:  "/",
 		Args: []string{"ps"},

libcontainer/integration/utils_test.go

@@ -231,3 +231,25 @@ func runContainerOk(t *testing.T, config *configs.Config, args ...string) *stdBu
 func destroyContainer(container *libcontainer.Container) {
 	_ = container.Destroy()
 }
+
+func waitStdOut(stdout *os.File) chan error {
+	ch := make(chan error, 1)
+	buf := make([]byte, 1)
+	go func() {
+		defer close(ch)
+
+		for {
+			n, err := stdout.Read(buf)
+			if err != nil {
+				ch <- err
+				return
+			}
+
+			if n >= 0 {
+				ch <- nil
+				return
+			}
+		}
+	}()
+	return ch
+}