[audio] Add AudioManager getNativeInterface

Migrate to a sub-interface for native accessibly methods so we don't
have to manually parcel/transact new additions. The existing methods
will either be removed, or folded into the native interface via ongoing
refactoring.

Test: compiles
Bug: 376481063
Flag: EXEMPT mechanical refactor
Change-Id: Ief320a181c1c21076f1b1c8d1372808505bcd460

Author: atneya

include/audiomanager/IAudioManager.h

@@ -17,6 +17,7 @@
 #ifndef ANDROID_IAUDIOMANAGER_H
 #define ANDROID_IAUDIOMANAGER_H
 
+#include <android/media/IAudioManagerNative.h>
 #include <audiomanager/AudioManager.h>
 #include <utils/Errors.h>
 #include <binder/IInterface.h>
@@ -34,20 +35,23 @@ class IAudioManager : public IInterface
     // These transaction IDs must be kept in sync with the method order from
     // IAudioService.aidl.
     enum {
-        TRACK_PLAYER                          = IBinder::FIRST_CALL_TRANSACTION,
-        PLAYER_ATTRIBUTES                     = IBinder::FIRST_CALL_TRANSACTION + 1,
-        PLAYER_EVENT                          = IBinder::FIRST_CALL_TRANSACTION + 2,
-        RELEASE_PLAYER                        = IBinder::FIRST_CALL_TRANSACTION + 3,
-        TRACK_RECORDER                        = IBinder::FIRST_CALL_TRANSACTION + 4,
-        RECORDER_EVENT                        = IBinder::FIRST_CALL_TRANSACTION + 5,
-        RELEASE_RECORDER                      = IBinder::FIRST_CALL_TRANSACTION + 6,
-        PLAYER_SESSION_ID                     = IBinder::FIRST_CALL_TRANSACTION + 7,
-        PORT_EVENT                            = IBinder::FIRST_CALL_TRANSACTION + 8,
-        PERMISSION_UPDATE_BARRIER             = IBinder::FIRST_CALL_TRANSACTION + 9,
+        GET_NATIVE_INTERFACE                  = IBinder::FIRST_CALL_TRANSACTION,
+        TRACK_PLAYER                          = IBinder::FIRST_CALL_TRANSACTION + 1,
+        PLAYER_ATTRIBUTES                     = IBinder::FIRST_CALL_TRANSACTION + 2,
+        PLAYER_EVENT                          = IBinder::FIRST_CALL_TRANSACTION + 3,
+        RELEASE_PLAYER                        = IBinder::FIRST_CALL_TRANSACTION + 4,
+        TRACK_RECORDER                        = IBinder::FIRST_CALL_TRANSACTION + 5,
+        RECORDER_EVENT                        = IBinder::FIRST_CALL_TRANSACTION + 6,
+        RELEASE_RECORDER                      = IBinder::FIRST_CALL_TRANSACTION + 7,
+        PLAYER_SESSION_ID                     = IBinder::FIRST_CALL_TRANSACTION + 8,
+        PORT_EVENT                            = IBinder::FIRST_CALL_TRANSACTION + 9,
+        PERMISSION_UPDATE_BARRIER             = IBinder::FIRST_CALL_TRANSACTION + 10,
     };
 
     DECLARE_META_INTERFACE(AudioManager)
 
+    virtual sp<media::IAudioManagerNative> getNativeInterface() = 0;
+
     // The parcels created by these methods must be kept in sync with the
     // corresponding methods from IAudioService.aidl and objects it imports.
     virtual audio_unique_id_t trackPlayer(player_type_t playerType, audio_usage_t usage,

services/audiomanager/Android.bp

@@ -15,6 +15,7 @@ cc_library {
     ],
 
     shared_libs: [
+        "av-types-aidl-cpp",
         "libutils",
         "libbinder",
         "liblog",

services/audiomanager/IAudioManager.cpp

@@ -35,6 +35,24 @@ class BpAudioManager : public BpInterface<IAudioManager>
     {
     }
 
+    // This should never fail
+    virtual sp<media::IAudioManagerNative> getNativeInterface() {
+        Parcel data, reply;
+        data.writeInterfaceToken(IAudioManager::getInterfaceDescriptor());
+        const status_t res = remote()->transact(GET_NATIVE_INTERFACE, data, &reply, 0);
+        LOG_ALWAYS_FATAL_IF(res != OK, "%s failed with result %d", __func__, res);
+        const int ex = reply.readExceptionCode();
+        LOG_ALWAYS_FATAL_IF(ex != binder::Status::EX_NONE, "%s failed with exception %d",
+                            __func__,
+                            ex);
+        sp<IBinder> binder;
+        const status_t err = reply.readNullableStrongBinder(&binder);
+        LOG_ALWAYS_FATAL_IF(binder == nullptr, "%s failed unexpected nullptr %d", __func__, err);
+        const auto iface = checked_interface_cast<media::IAudioManagerNative>(std::move(binder));
+        LOG_ALWAYS_FATAL_IF(iface == nullptr, "%s failed unexpected interface", __func__);
+        return iface;
+    }
+
     virtual audio_unique_id_t trackPlayer(player_type_t playerType, audio_usage_t usage,
             audio_content_type_t content, const sp<IBinder>& player, audio_session_t sessionId) {
         Parcel data, reply;