audio policy: add routing update client interface

Added IAudioPolicyServiceClient client binder interface
for client process to receive notifications from AudioPolicyService
when audio ports are added/removed or audio patches created/released.

The audio patches owned by a given client are automatically released when
this client binder dies.

Bug: 14815883.

Change-Id: I6013f6aec03b50565cffb1ad2cd1f0f8852032c5
diff --git a/media/libmedia/IAudioPolicyServiceClient.cpp b/media/libmedia/IAudioPolicyServiceClient.cpp
new file mode 100644
index 0000000..e802277
--- /dev/null
+++ b/media/libmedia/IAudioPolicyServiceClient.cpp
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2009 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.
+ */
+
+#define LOG_TAG "IAudioPolicyServiceClient"
+#include <utils/Log.h>
+
+#include <stdint.h>
+#include <sys/types.h>
+
+#include <binder/Parcel.h>
+
+#include <media/IAudioPolicyServiceClient.h>
+#include <media/AudioSystem.h>
+
+namespace android {
+
+enum {
+    PORT_LIST_UPDATE = IBinder::FIRST_CALL_TRANSACTION,
+    PATCH_LIST_UPDATE
+};
+
+class BpAudioPolicyServiceClient : public BpInterface<IAudioPolicyServiceClient>
+{
+public:
+    BpAudioPolicyServiceClient(const sp<IBinder>& impl)
+        : BpInterface<IAudioPolicyServiceClient>(impl)
+    {
+    }
+
+    void onAudioPortListUpdate()
+    {
+        Parcel data, reply;
+        data.writeInterfaceToken(IAudioPolicyServiceClient::getInterfaceDescriptor());
+        remote()->transact(PORT_LIST_UPDATE, data, &reply, IBinder::FLAG_ONEWAY);
+    }
+
+    void onAudioPatchListUpdate()
+    {
+        Parcel data, reply;
+        data.writeInterfaceToken(IAudioPolicyServiceClient::getInterfaceDescriptor());
+        remote()->transact(PATCH_LIST_UPDATE, data, &reply, IBinder::FLAG_ONEWAY);
+    }
+};
+
+IMPLEMENT_META_INTERFACE(AudioPolicyServiceClient, "android.media.IAudioPolicyServiceClient");
+
+// ----------------------------------------------------------------------
+
+status_t BnAudioPolicyServiceClient::onTransact(
+    uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags)
+{
+    switch (code) {
+    case PORT_LIST_UPDATE: {
+            CHECK_INTERFACE(IAudioPolicyServiceClient, data, reply);
+            onAudioPortListUpdate();
+            return NO_ERROR;
+        } break;
+    case PATCH_LIST_UPDATE: {
+            CHECK_INTERFACE(IAudioPolicyServiceClient, data, reply);
+            onAudioPatchListUpdate();
+            return NO_ERROR;
+        } break;
+    default:
+        return BBinder::onTransact(code, data, reply, flags);
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+}; // namespace android