onStopListener double-fires and races with active captures

[rogue-socket]

Summary

MediaProjectionController.stopInternal() can invoke onStopListener twice, and the listener (ScreenCaptureManager.releaseResources()) is unsynchronized — creating a race condition with in-progress captures that can crash the app.

Double invocation path

In stopInternal() (lines 73-88):

1. unregisterCallback() throws IllegalStateException (line 79, caught and swallowed) — callback remains registered
2. projection.stop() (line 83) triggers the callback's onStop() (line 30-33), which invokes onStopListener — first fire
3. Line 87 invokes onStopListener unconditionally — second fire

Spurious invocation

When projection is already null (e.g., during first initialize() call), line 87 still fires onStopListener. This calls releaseResources() with nothing to release.

Race condition

releaseResources() (ScreenCaptureManager.kt:178-188) is not synchronized. It can run from:

• The onStop callback (main/binder thread)
• stopInternal (any thread)

If a capture is in progress (holding the Mutex on Dispatchers.Default):

• imageReader can be closed while awaitImage() is waiting on it
• handlerThread can be quit while OnImageAvailableListener is dispatching
• virtualDisplay can be released while ImageReader expects frames

This can produce IllegalStateException crashes.

Files

• action-executor/src/main/java/com/scroller/agent/executor/MediaProjectionController.kt (lines 73-88, 29-33)
• action-executor/src/main/java/com/scroller/agent/executor/ScreenCaptureManager.kt (lines 44-47, 178-188)