Move mount to core/mount

Signed-off-by: Derek McGowan <derek@mcg.dev>

core/mount/losetup_linux_test.go

@@ -0,0 +1,165 @@
+/*
+   Copyright The containerd Authors.
+
+   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 mount
+
+import (
+	"os"
+	"testing"
+	"time"
+
+	"github.com/containerd/continuity/testutil"
+)
+
+var randomData = []byte("randomdata")
+
+func createTempFile(t *testing.T) string {
+	t.Helper()
+
+	f, err := os.CreateTemp("", "losetup")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+
+	if err = f.Truncate(512); err != nil {
+		t.Fatal(err)
+	}
+
+	return f.Name()
+}
+
+func TestNonExistingLoop(t *testing.T) {
+	testutil.RequiresRoot(t)
+
+	backingFile := "setup-loop-test-no-such-file"
+	_, err := setupLoop(backingFile, LoopParams{})
+	if err == nil {
+		t.Fatalf("setupLoop with non-existing file should fail")
+	}
+}
+
+func TestRoLoop(t *testing.T) {
+	testutil.RequiresRoot(t)
+
+	backingFile := createTempFile(t)
+	defer func() {
+		if err := os.Remove(backingFile); err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	file, err := setupLoop(backingFile, LoopParams{Readonly: true, Autoclear: true})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer file.Close()
+
+	if _, err := file.Write(randomData); err == nil {
+		t.Fatalf("writing to readonly loop device should fail")
+	}
+}
+
+func TestRwLoop(t *testing.T) {
+	testutil.RequiresRoot(t)
+
+	backingFile := createTempFile(t)
+	defer func() {
+		if err := os.Remove(backingFile); err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	file, err := setupLoop(backingFile, LoopParams{Autoclear: true})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer file.Close()
+
+	if _, err := file.Write(randomData); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestAttachDetachLoopDevice(t *testing.T) {
+	testutil.RequiresRoot(t)
+
+	path := createTempFile(t)
+	defer func() {
+		if err := os.Remove(path); err != nil {
+			t.Fatal(err)
+		}
+	}()
+
+	dev, err := AttachLoopDevice(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if err = DetachLoopDevice(dev); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestAutoclearTrueLoop(t *testing.T) {
+	testutil.RequiresRoot(t)
+
+	dev := func() string {
+		backingFile := createTempFile(t)
+		defer func() {
+			if err := os.Remove(backingFile); err != nil {
+				t.Fatal(err)
+			}
+		}()
+
+		file, err := setupLoop(backingFile, LoopParams{Autoclear: true})
+		if err != nil {
+			t.Fatal(err)
+		}
+		dev := file.Name()
+		file.Close()
+		return dev
+	}()
+	time.Sleep(100 * time.Millisecond)
+	if err := removeLoop(dev); err == nil {
+		t.Fatalf("removeLoop should fail if Autoclear is true")
+	}
+}
+
+func TestAutoclearFalseLoop(t *testing.T) {
+	testutil.RequiresRoot(t)
+
+	dev := func() string {
+		backingFile := createTempFile(t)
+		defer func() {
+			if err := os.Remove(backingFile); err != nil {
+				t.Fatal(err)
+			}
+		}()
+
+		file, err := setupLoop(backingFile, LoopParams{Autoclear: false})
+		if err != nil {
+			t.Fatal(err)
+		}
+		dev := file.Name()
+		file.Close()
+		return dev
+	}()
+	time.Sleep(100 * time.Millisecond)
+	if err := removeLoop(dev); err != nil {
+		t.Fatal(err)
+	}
+}