Preprocessed uses the same syntax of AIDL

Preprocessed file has been using a similar but different syntax.  Now,
it is using the same syntax with AIDL files with a couple of small
changes.

- Type decl can have qualified name.
  (interestinly, I only changed this for interface/enum)
- Interface can omit body(members) blocks.
  interface IFoo; // is simply an empty interface

Bug: 25479378
Test: aidl_unittests
Test: m
Change-Id: Icf5e4c321c469af00506c5ff14782251018d9d57

1 files changed, 28 insertions, 0 deletions

diff --git a/preprocess.h b/preprocess.h
new file mode 100644
index 00000000..d734a685
--- /dev/null
+++ b/preprocess.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2021, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "aidl_language.h"
+#include "code_writer.h"
+
+namespace android {
+namespace aidl {
+
+bool Preprocess(const Options& options, const IoDelegate& io_delegate);
+
+}  // namespace aidl
+}  // namespace android