fix: improve getting current directory

README.md

@@ -89,10 +89,13 @@ ftpServer.listen()
 - __password__
   - Password provided in the `PASS` command
   - Only provided if `anonymous` is set to `false`
-- __resolve ({fs, cwd, blacklist, whitelist})__
+- __resolve ({fs, root, cwd, blacklist, whitelist})__
   - __fs__ _[optional]_
     - Optional file system class for connection to use
     - See [File System](#file-system) for implementation details
+  - __root__ _[optional]_
+    - If `fs` not provided, will set the root directory for the connection
+    - The user cannot traverse lower than this directory
   - __cwd__ _[optional]_
     - If `fs` not provided, will set the starting directory for the connection
   - __blacklist__ _[optional]_

src/fs.js

@@ -13,8 +13,8 @@ class FileSystem {
     cwd = '/'
   } = {}) {
     this.connection = connection;
-    this.cwd = cwd;
-    this.root = root;
+    this.cwd = nodePath.resolve(cwd);
+    this.root = nodePath.resolve(root);
   }
 
   _resolvePath(path) {
@@ -60,7 +60,7 @@ class FileSystem {
       if (!stat.isDirectory()) throw new errors.FileSystemError('Not a valid directory');
     })
     .then(() => {
-      this.cwd = path.replace(new RegExp(`^${this.root}`), '') || '/';
+      this.cwd = path.substring(this.root.length) || '/';
       return this.currentDirectory();
     });
   }