Refactored inode.LookUpChild.

samples/memfs/inode.go

@@ -116,22 +116,18 @@ func (inode *inode) checkInvariants() {
 	}
 }
 
-////////////////////////////////////////////////////////////////////////
-// Public methods
-////////////////////////////////////////////////////////////////////////
-
-// Find an entry for the given child name and return its inode ID.
+// Return the index of the child within inode.entries, if it exists.
 //
 // REQUIRES: inode.dir
 // SHARED_LOCKS_REQUIRED(inode.mu)
-func (inode *inode) LookUpChild(name string) (id fuse.InodeID, ok bool) {
+func (inode *inode) findChild(name string) (i int, ok bool) {
 	if !inode.dir {
-		panic("LookUpChild called on non-directory.")
+		panic("findChild called on non-directory.")
 	}
 
-	for _, e := range inode.entries {
+	var e fuseutil.Dirent
+	for i, e = range inode.entries {
 		if e.Name == name {
-			id = e.Inode
 			ok = true
 			return
 		}
@@ -140,6 +136,23 @@ func (inode *inode) LookUpChild(name string) (id fuse.InodeID, ok bool) {
 	return
 }
 
+////////////////////////////////////////////////////////////////////////
+// Public methods
+////////////////////////////////////////////////////////////////////////
+
+// Find an entry for the given child name and return its inode ID.
+//
+// REQUIRES: inode.dir
+// SHARED_LOCKS_REQUIRED(inode.mu)
+func (inode *inode) LookUpChild(name string) (id fuse.InodeID, ok bool) {
+	index, ok := inode.findChild(name)
+	if ok {
+		id = inode.entries[index].Inode
+	}
+
+	return
+}
+
 // Add an entry for a child.
 //
 // REQUIRES: inode.dir
@@ -167,7 +180,7 @@ func (inode *inode) RemoveChild(name string)
 
 // Serve a ReadDir request.
 //
-// REQUIRED: inode.dir
+// REQUIRES: inode.dir
 // SHARED_LOCKS_REQUIRED(inode.mu)
 func (inode *inode) ReadDir(offset int, size int) (data []byte, err error) {
 	if !inode.dir {