Make Isolated file system writable only if it is configured so

webkit/fileapi/isolated_context_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "webkit/fileapi/isolated_context.h"
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
@@ skipping 147 matching lines @@
   ASSERT_EQ(id_, cracked_id);
 
   // Trying to crack "/foo" should fail (because "foo" is not the one
   // included in the kTestPaths).
   virtual_path = isolated_context()->CreateVirtualPath(
       id_, FilePath(FPL("foo")));
   ASSERT_FALSE(isolated_context()->CrackIsolatedPath(
       virtual_path, &cracked_id, &root_path, &cracked_path));
 }
 
+TEST_F(IsolatedContextTest, Writable) {
+  // By default the file system must be read-only.
+  ASSERT_FALSE(isolated_context()->IsWritable(id_));
+
+  // Set writable.
+  ASSERT_TRUE(isolated_context()->SetWritable(id_, true));
+  ASSERT_TRUE(isolated_context()->IsWritable(id_));
+
+  // Set non-writable.
+  ASSERT_TRUE(isolated_context()->SetWritable(id_, false));
+  ASSERT_FALSE(isolated_context()->IsWritable(id_));
+
+  // Set writable again, and revoke the filesystem.
+  ASSERT_TRUE(isolated_context()->SetWritable(id_, true));
+  isolated_context()->RevokeIsolatedFileSystem(id_);
+
+  // IsWritable should return false for non-registered file system.
+  ASSERT_FALSE(isolated_context()->IsWritable(id_));
+  // SetWritable should also return false for non-registered file system
+  // (no matter what value we give).
+  ASSERT_FALSE(isolated_context()->SetWritable(id_, true));
+  ASSERT_FALSE(isolated_context()->SetWritable(id_, false));
+}
+
 }  // namespace fileapi