Allows autoconfiguration of directories that were symlinked into

the root path.

unionfs/autounion.go

@@ -10,6 +10,7 @@ import (
 	"syscall"
 	"sync"
 	"time"
+	"io/ioutil"
 )
 
 // Creates unions for all files under a given directory,
@@ -168,7 +169,18 @@ func (me *AutoUnionFs) VisitFile(path string, f *os.FileInfo) {
 
 func (me *AutoUnionFs) updateKnownFses() {
 	log.Println("Looking for new filesystems")
-	filepath.Walk(me.root, me, nil)
+	// We unroll the first level of entries in the root manually in order
+	// to allow symbolic links on that level.
+	directoryEntries, err := ioutil.ReadDir(me.root)
+	if err == nil {
+		for _, dir := range directoryEntries {
+			if dir.IsDirectory() || dir.IsSymlink() {
+				path := filepath.Join(me.root, dir.Name)
+				me.VisitDir(path, nil)
+				filepath.Walk(path, me, nil)
+			}
+		}
+	}
 	log.Println("Done looking")
 }
 

unionfs/autounion_test.go

@@ -73,7 +73,7 @@ func TestAutoFsSymlink(t *testing.T) {
 	err := os.Mkdir(wd+"/store/backing1", 0755)
 	CheckSuccess(err)
 
-	os.Symlink(wd+"/ro", wd+"/store/backing1/READONLY")
+	err = os.Symlink(wd+"/ro", wd+"/store/backing1/READONLY")
 	CheckSuccess(err)
 
 	err = os.Symlink(wd+"/store/backing1", wd+"/mount/config/manual1")
@@ -109,6 +109,29 @@ func TestAutoFsSymlink(t *testing.T) {
 	CheckSuccess(err)
 }
 
+func TestDetectSymlinkedDirectories(t *testing.T) {
+	wd, clean := setup(t)
+	defer clean()
+
+	err := os.Mkdir(wd+"/backing1", 0755)
+	CheckSuccess(err)
+
+	err = os.Symlink(wd+"/ro", wd+"/backing1/READONLY")
+	CheckSuccess(err)
+
+	err = os.Symlink(wd+"/backing1", wd+"/store/backing1")
+	CheckSuccess(err)
+
+	scan := wd + "/mount/config/" + _SCAN_CONFIG
+	err = ioutil.WriteFile(scan, []byte("something"), 0644)
+	if err != nil {
+		t.Error("error writing:", err)
+	}
+
+	_, err = os.Lstat(wd + "/mount/backing1")
+	CheckSuccess(err)
+}
+
 func TestExplicitScan(t *testing.T) {
 	wd, clean := setup(t)
 	defer clean()