Implement audio devices and streams HAL delegating to legacy HAL

Changes made to the .hal definition:

  - introduce Effect ID returned by the IEffectsFactory that
    needs to be passed to IStream.{add|remove}Effect; otherwise
    it's impossible to retrieve the underlying HAL effect handle;

  - change "bus address" in DeviceAddress to "string" type;

  - fix signature of some methods w.r.t. returning Result;

  - remove unused "struct AudioPatch".

Bug: 30222631
Test: make
Change-Id: Icb51729ef57bb2a5b0b78609735e7481bc04f95c
diff --git a/audio/common/2.0/default/EffectMap.cpp b/audio/common/2.0/default/EffectMap.cpp
new file mode 100644
index 0000000..703b91c
--- /dev/null
+++ b/audio/common/2.0/default/EffectMap.cpp
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#include <atomic>
+
+#include "EffectMap.h"
+
+namespace android {
+
+ANDROID_SINGLETON_STATIC_INSTANCE(EffectMap);
+
+// static
+const uint64_t EffectMap::INVALID_ID = 0;
+
+// static
+uint64_t EffectMap::makeUniqueId() {
+    static std::atomic<uint64_t> counter{INVALID_ID + 1};
+    return counter++;
+}
+
+uint64_t EffectMap::add(effect_handle_t handle) {
+    uint64_t newId = makeUniqueId();
+    std::lock_guard<std::mutex> lock(mLock);
+    mEffects.add(newId, handle);
+    return newId;
+}
+
+effect_handle_t EffectMap::get(const uint64_t& id) {
+    std::lock_guard<std::mutex> lock(mLock);
+    ssize_t idx = mEffects.indexOfKey(id);
+    return idx >= 0 ? mEffects[idx] : NULL;
+}
+
+void EffectMap::remove(effect_handle_t handle) {
+    std::lock_guard<std::mutex> lock(mLock);
+    for (size_t i = 0; i < mEffects.size(); ++i) {
+        if (mEffects[i] == handle) {
+            mEffects.removeItemsAt(i);
+            break;
+        }
+    }
+}
+
+}  // namespace android