Check in gVisor.

PiperOrigin-RevId: 194583126
Change-Id: Ica1d8821a90f74e7e745962d71801c598c652463

1 files changed, 70 insertions, 0 deletions

diff --git a/pkg/sentry/fs/host/wait_test.go b/pkg/sentry/fs/host/wait_test.go
new file mode 100644
index 000000000..c5f5c9c0d
--- /dev/null
+++ b/pkg/sentry/fs/host/wait_test.go
@@ -0,0 +1,70 @@
+// Copyright 2018 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package host
+
+import (
+	"syscall"
+	"testing"
+	"time"
+
+	"gvisor.googlesource.com/gvisor/pkg/sentry/context/contexttest"
+	"gvisor.googlesource.com/gvisor/pkg/sentry/fs"
+	"gvisor.googlesource.com/gvisor/pkg/waiter"
+)
+
+func TestWait(t *testing.T) {
+	var fds [2]int
+	err := syscall.Pipe(fds[:])
+	if err != nil {
+		t.Fatalf("Unable to create pipe: %v", err)
+	}
+
+	defer syscall.Close(fds[1])
+
+	ctx := contexttest.Context(t)
+	file, err := NewFile(ctx, fds[0], fs.RootOwner)
+	if err != nil {
+		syscall.Close(fds[0])
+		t.Fatalf("NewFile failed: %v", err)
+	}
+
+	defer file.DecRef()
+
+	r := file.Readiness(waiter.EventIn)
+	if r != 0 {
+		t.Fatalf("File is ready for read when it shouldn't be.")
+	}
+
+	e, ch := waiter.NewChannelEntry(nil)
+	file.EventRegister(&e, waiter.EventIn)
+	defer file.EventUnregister(&e)
+
+	// Check that there are no notifications yet.
+	if len(ch) != 0 {
+		t.Fatalf("Channel is non-empty")
+	}
+
+	// Write to the pipe, so it should be writable now.
+	syscall.Write(fds[1], []byte{1})
+
+	// Check that we get a notification. We need to yield the current thread
+	// so that the fdnotifier can deliver notifications, so we use a
+	// 1-second timeout instead of just checking the length of the channel.
+	select {
+	case <-ch:
+	case <-time.After(1 * time.Second):
+		t.Fatalf("Channel not notified")
+	}
+}