Implement AAudio for modern Android devices

[SDLBugzilla]

This bug report was migrated from our old Bugzilla tracker.

Reported in version: HG 2.0
Reported for operating system, platform: Android (All), All

Comments on the original bug report:

On 2020-05-29 05:14:13 +0000, Ryan C. Gordon wrote:

Modern Android releases have an audio API called AAudio...

https://developer.android.com/ndk/guides/audio/aaudio/aaudio

...which is meant to be preferred over OpenSL ES. Implement this (leaving our OpenSL ES target as a fallback for older devices, of course).

--ryan.

[icculus]

Assigning myself for now, but this is probably post-2.0.16 work. Feel free to steal if you want to work on this!

[1bsyl]

I've added the AAudio back-end, nothing special except:

• it dynamically loads the libaaudio.so, which may not be present if the API < 26
• uses GetDeviceBuf / PlayDevice, with SDL_RunAudio thread
• tested with playback and capture

List of commits:

• Android: OpenSLES, explicitly initialise the global variable 'bqPlayer' 4118fe6
• Android: add AAudio back-end, with playback and capture: 04b2f5f
• AAudio: add bootstrap in SDL_audio.c f1fab24
• AAudio: add compilation to Android.mk, but not activated in SDL_config_android.h 146656c
• Android: add openslES and AAudio compilation to CMakeLists 02b1ebc
• AAudio: add aaudio pause/resume function to android events loop b4f89c5
• Android: add AAudio entry in CMake SDL_config 859230e

TODO:
enable audio for Android.mk, and CMake :

• https://github.com/libsdl-org/SDL/blob/main/CMakeLists.txt
• https://github.com/libsdl-org/SDL/blob/main/include/SDL_config_android.h
• also configure.ac ? https://github.com/libsdl-org/SDL/blob/main/configure.ac#L3627
  (if so, update also for OpenSLES)

[icculus]

Ooh, nice work!

Let's leave it inactive in the config until 2.0.16 ships, and then make it the default right after, so it has time for testing.

[1bsyl]

ok!

[icculus]

Marking with 2.0.18 milestone so we don't forget to flip this in the config. :)