Add AIDL implementation for the vendor HAL service.

Bug: 205044134
Test: Pass AIDL VTS tests and regression tests.
Change-Id: Iad04ce01f71fc220443e05a4be05d7d5545227e8
diff --git a/wifi/aidl/default/ringbuffer.h b/wifi/aidl/default/ringbuffer.h
new file mode 100644
index 0000000..80c0c11
--- /dev/null
+++ b/wifi/aidl/default/ringbuffer.h
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+
+#ifndef RINGBUFFER_H_
+#define RINGBUFFER_H_
+
+#include <list>
+#include <vector>
+
+namespace aidl {
+namespace android {
+namespace hardware {
+namespace wifi {
+
+/**
+ * Ringbuffer object used to store debug data.
+ */
+class Ringbuffer {
+  public:
+    // Error codes for the append ring buffer operation
+    enum AppendStatus {
+        SUCCESS,
+        FAIL_GENERIC,
+        FAIL_IP_BUFFER_ZERO,
+        FAIL_IP_BUFFER_EXCEEDED_MAXSIZE,
+        FAIL_RING_BUFFER_CORRUPTED
+    };
+    explicit Ringbuffer(size_t maxSize);
+
+    // Appends the data buffer and deletes from the front until buffer is
+    // within |maxSize_|.
+    enum AppendStatus append(const std::vector<uint8_t>& input);
+    const std::list<std::vector<uint8_t>>& getData() const;
+    void clear();
+
+  private:
+    std::list<std::vector<uint8_t>> data_;
+    size_t size_;
+    size_t maxSize_;
+};
+
+}  // namespace wifi
+}  // namespace hardware
+}  // namespace android
+}  // namespace aidl
+
+#endif  // RINGBUFFER_H_