Add Oboe 1.4.3, used only for Android build.

2026-08-18 03:34:25 +02:00 · 2021-02-12 19:55:07 +08:00
parent cfecce7010
commit 4c5040b2e7
393 changed files with 34708 additions and 0 deletions
@@ -0,0 +1,71 @@
+[Tech Notes Home](README.md)
+
+# Assert in releaseBuffer()
+
+There is a bug that can sometimes cause an assert in ClientProxy or AudioTrackShared::releaseBuffer() when headsets are connected or disconnected. 
+The bug was originally reported at: https://github.com/google/oboe/issues/535
+
+You will see signatures like this in the logcat:
+
+    F AudioTrackShared: releaseBuffer: mUnreleased out of range, !(stepCount:96 <= mUnreleased:0 <= mFrameCount:480), BufferSizeInFrames:480
+
+## Platforms Affected
+
+Android version 10 (Q) or earlier.
+
+Oboe version 1.4.0 or earlier when using OpenSLES with an OUTPUT stream callback.
+
+OR any version of Oboe if:
+* Oboe is using using OpenSL ES or a non-MMAP Legacy AAudio stream
+* AND you call stream->getFramesRead() or stream->getTimestamp(...) from inside
+an OUTPUT stream callback,
+
+It does **not** happen when Oboe uses AAudio MMAP because it does not call releaseBuffer().
+
+## Workarounds
+
+1. Use Oboe 1.4.1 or later.
+1. Do not call stream->getFramesRead() or stream->getTimestamp() from inside the callback of an OUTPUT stream. If you absolutely must, then call them at the beginning of your callback to reduce the probability of a crash.
+
+Here is a [fix in Oboe 1.4.1](https://github.com/google/oboe/pull/863) that removed a call to getPosition().
+
+## Root Cause
+
+The sequence of events is:
+1. AudioFlinger AudioTrack obtains a buffer from the audio device
+1. user plugs in headphones, which invalidates the audio device
+1. app is called (callback) to render audio using the buffer
+1. the app or Oboe calls getFramesRead() or getTimestamp(), which calls down to AudioTrack::getPosition() or AudioTrack::getTimestamp()
+1. device routing change occurs because the audio device is [invalid](https://cs.android.com/android/platform/superproject/+/master:frameworks/av/media/libaudioclient/AudioTrack.cpp;l=1239;drc=48e98cf8dbd9fa212a0e129822929dc40e6c3898)
+1. callback ends by releasing the buffer back to a different device
+1. AudioTrackShared::releaseBuffer() checks to make sure the device matches the one in ObtainBuffer() and asserts if they do not match.
+
+Oboe, before V1.4.1, would update the server position in its callback. This called getPosition() in OpenSL ES, which called AudioTrack::getPosition().
+
+The probability of the assert() is proportional to the time that the CPU spends between obtaining a buffer and calling restoreTrack_l().
+
+This bug is tracked internally at: b/136268149
+
+## Reproduce the Bug
+
+These steps will trigger the bug most of the time:
+
+1. Install OboeTester 1.5.22 or later, with Oboe < 1.4.1
+1. Enter in a Terminal window: adb logcat | grep releaseBuffer
+1. Launch OboeTester
+1. Click TEST OUTPUT
+1. Select API: OpenSL ES
+1. Click OPEN
+1. Click START, you should hear a tone
+1. Slide "Workload" fader slowly up until you hear bad glitches.
+1. Plug in headphones.
+ 
+You may see a message like this in the logcat:
+
+    AudioTrackShared: releaseBuffer: mUnreleased out of range, !(stepCount:96 <= mUnreleased:0 <= mFrameCount:480), BufferSizeInFrames:480
+
+# OEM Information
+
+These patches are available in Q AOSP:
+1. [AudioTrack](https://android-review.googlesource.com/c/platform/frameworks/av/+/1251871/)
+1. [AudioRecord](https://android-review.googlesource.com/c/platform/frameworks/av/+/1251872/)