diriv: handle directory rename over directory

If an empty directory is overwritten we will always get
ENOTEMPTY as the "empty" directory will still contain gocryptfs.diriv.
Handle that case by removing the target directory and trying again.

Fixes issue #10

4 files changed, 19 insertions, 0 deletions

diff --git a/pathfs_frontend/file.go b/pathfs_frontend/file.go
index cf6b192..1f71bfb 100644
--- a/pathfs_frontend/file.go
+++ b/pathfs_frontend/file.go
@@ -1,5 +1,7 @@
 package pathfs_frontend
 
+// FUSE operations on file handles
+
 import (
 	"bytes"
 	"fmt"
diff --git a/pathfs_frontend/file_holes.go b/pathfs_frontend/file_holes.go
index 3db4828..fd2e2c1 100644
--- a/pathfs_frontend/file_holes.go
+++ b/pathfs_frontend/file_holes.go
@@ -1,5 +1,7 @@
 package pathfs_frontend
 
+// Helper functions for sparse files (files with holes)
+
 import (
 	"github.com/hanwen/go-fuse/fuse"
 	"github.com/rfjakob/gocryptfs/cryptfs"
diff --git a/pathfs_frontend/fs.go b/pathfs_frontend/fs.go
index f853556..e930228 100644
--- a/pathfs_frontend/fs.go
+++ b/pathfs_frontend/fs.go
@@ -1,5 +1,7 @@
 package pathfs_frontend
 
+// FUSE operations on paths
+
 import (
 	"encoding/base64"
 	"os"
@@ -300,6 +302,17 @@ func (fs *FS) Rename(oldPath string, newPath string, context *fuse.Context) (cod
 	fs.CryptFS.DirIVCacheEnc.Clear()
 
 	err = os.Rename(cOldPath, cNewPath)
+
+	if lerr, ok := err.(*os.LinkError); ok && lerr.Err == syscall.ENOTEMPTY {
+		// If an empty directory is overwritten we will always get
+		// ENOTEMPTY as the "empty" directory will still contain gocryptfs.diriv.
+		// Handle that case by removing the target directory and trying again.
+		cryptfs.Debug.Printf("Rename: Handling ENOTEMPTY\n")
+		if fs.Rmdir(newPath, context) == fuse.OK {
+			err = os.Rename(cOldPath, cNewPath)
+		}
+	}
+
 	return fuse.ToStatus(err)
 }
 
diff --git a/pathfs_frontend/fs_dir.go b/pathfs_frontend/fs_dir.go
index 9b319f8..0f255d9 100644
--- a/pathfs_frontend/fs_dir.go
+++ b/pathfs_frontend/fs_dir.go
@@ -1,5 +1,7 @@
 package pathfs_frontend
 
+// Mkdir and Rmdir
+
 import (
 	"fmt"
 	"os"