implement ModTime via FUSE for remotes that support it (fixes #1197)

cmd/mount/dir.go

@@ -169,7 +169,7 @@ func (d *Dir) isEmpty() (bool, error) {
 // Check interface satsified
 var _ fusefs.Node = (*Dir)(nil)
 
-// Attr updates the attribes of a directory
+// Attr updates the attributes of a directory
 func (d *Dir) Attr(ctx context.Context, a *fuse.Attr) error {
 	a.Gid = gid
 	a.Uid = uid
@@ -183,6 +183,27 @@ func (d *Dir) Attr(ctx context.Context, a *fuse.Attr) error {
 	return nil
 }
 
+// Check interface satisfied
+var _ fusefs.NodeSetattrer = (*Dir)(nil)
+
+// Setattr handles attribute changes from FUSE. Currently supports ModTime only.
+func (d *Dir) Setattr(ctx context.Context, req *fuse.SetattrRequest, resp *fuse.SetattrResponse) error {
+	if noModTime {
+		return nil
+	}
+
+	d.mu.Lock()
+	defer d.mu.Unlock()
+
+	if req.Valid.MtimeNow() {
+		d.modTime = time.Now()
+	} else if req.Valid.Mtime() {
+		d.modTime = req.Mtime
+	}
+
+	return nil
+}
+
 // lookupNode calls lookup then makes sure the node is not nil in the DirEntry
 func (d *Dir) lookupNode(leaf string) (item *DirEntry, err error) {
 	item, err = d.lookup(leaf)

cmd/mount/dir_test.go

@@ -6,6 +6,7 @@ import (
 	"io/ioutil"
 	"os"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -133,3 +134,20 @@ func TestDirRenameFullDir(t *testing.T) {
 	run.rmdir(t, "dir")
 	run.checkDir(t, "")
 }
+
+func TestDirModTime(t *testing.T) {
+	run.skipIfNoFUSE(t)
+
+	run.mkdir(t, "dir")
+	mtime := time.Date(2012, 11, 18, 17, 32, 31, 0, time.UTC)
+	err := os.Chtimes(run.path("dir"), mtime, mtime)
+	require.NoError(t, err)
+
+	info, err := os.Stat(run.path("dir"))
+	require.NoError(t, err)
+
+	// avoid errors because of timezone differences
+	assert.Equal(t, info.ModTime().Unix(), mtime.Unix())
+
+	run.rmdir(t, "dir")
+}

cmd/mount/file.go

@@ -74,6 +74,47 @@ func (f *File) Attr(ctx context.Context, a *fuse.Attr) error {
 	return nil
 }
 
+// Check interface satisfied
+var _ fusefs.NodeSetattrer = (*File)(nil)
+
+// Setattr handles attribute changes from FUSE. Currently supports ModTime only.
+func (f *File) Setattr(ctx context.Context, req *fuse.SetattrRequest, resp *fuse.SetattrResponse) error {
+	if noModTime {
+		return nil
+	}
+
+	// if o is nil it isn't valid yet
+	o, err := f.waitForValidObject()
+	if err != nil {
+		return err
+	}
+
+	f.mu.Lock()
+	defer f.mu.Unlock()
+
+	var newTime time.Time
+	if req.Valid.MtimeNow() {
+		newTime = time.Now()
+	} else if req.Valid.Mtime() {
+		newTime = req.Mtime
+	}
+
+	if !newTime.IsZero() {
+		err := o.SetModTime(newTime)
+		switch err {
+		case nil:
+			fs.Debugf(o, "File.Setattr ModTime OK")
+		case fs.ErrorCantSetModTime:
+			// do nothing, in order to not break "touch somefile" if it exists already
+		default:
+			fs.Errorf(o, "File.Setattr ModTime error: %v", err)
+			return err
+		}
+	}
+
+	return nil
+}
+
 // Update the size while writing
 func (f *File) written(n int64) {
 	atomic.AddInt64(&f.size, n)

cmd/mount/file_test.go

@@ -0,0 +1,30 @@
+// +build linux darwin freebsd
+
+package mount
+
+import (
+	"os"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestFileModTime(t *testing.T) {
+	run.skipIfNoFUSE(t)
+
+	run.createFile(t, "file", "123")
+
+	mtime := time.Date(2012, 11, 18, 17, 32, 31, 0, time.UTC)
+	err := os.Chtimes(run.path("file"), mtime, mtime)
+	require.NoError(t, err)
+
+	info, err := os.Stat(run.path("file"))
+	require.NoError(t, err)
+
+	// avoid errors because of timezone differences
+	assert.Equal(t, info.ModTime().Unix(), mtime.Unix())
+
+	run.rm(t, "file")
+}

cmd/mount/mount.go

@@ -46,7 +46,7 @@ func init() {
 	umask = unix.Umask(0) // read the umask
 	unix.Umask(umask)     // set it back to what it was
 	cmd.Root.AddCommand(commandDefintion)
-	commandDefintion.Flags().BoolVarP(&noModTime, "no-modtime", "", noModTime, "Don't read the modification time (can speed things up).")
+	commandDefintion.Flags().BoolVarP(&noModTime, "no-modtime", "", noModTime, "Don't read/write the modification time (can speed things up).")
 	commandDefintion.Flags().BoolVarP(&debugFUSE, "debug-fuse", "", debugFUSE, "Debug the FUSE internals - needs -v.")
 	commandDefintion.Flags().BoolVarP(&noSeek, "no-seek", "", noSeek, "Don't allow seeking in files.")
 	commandDefintion.Flags().DurationVarP(&dirCacheTime, "dir-cache-time", "", dirCacheTime, "Time to cache directory entries for.")
@@ -130,8 +130,6 @@ files to be visible in the mount.
 ### TODO ###
 
   * Check hashes on upload/download
-  * Preserve timestamps
-  * Move directories
 `,
 	Run: func(command *cobra.Command, args []string) {
 		cmd.CheckArgs(2, 2, command, args)