fix(android): clear static event mapper on engine detach - #1112
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c-tshibas wants to merge 2 commits into
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fix(android): clear static event mapper on engine detach#1112c-tshibas wants to merge 2 commits into
c-tshibas wants to merge 2 commits into
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The RUM/Logs event mapper is stored in a static, process-wide singleton that is only ever overwritten, never cleared. When a Flutter engine is detached (app backgrounded and killed, hot restart, or Activity recreation on a config change), the mapper field still holds a JNI reference tied to that now-destroyed engine's Dart isolate. dd-sdk-android's RUM/Logs core keeps writing/uploading queued events on a background thread independent of any Flutter engine's lifecycle. When it invokes the stale mapper to serialize an event, it crashes with a SIGSEGV inside CallObjectMethod at a deterministic offset -- the fingerprint of a JNI call into a freed/torn-down reference. Clears the mapper in detachFromEngine() for both DatadogRumPlugin and DatadogLogsPlugin, and marks both mapper fields @volatile so a clear from the main thread is guaranteed visible to the background writer thread reading it. Refs: RUMS-6227
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What & why
Fixes a native crash reported in RUMS-6227: Android SIGSEGV inside JNI
CallObjectMethod, at a consistent/deterministic offset.The RUM/Logs event mapper (
DatadogRumEventMapper/DatadogLogEventMapper)is held in a static, process-wide singleton in
DatadogRumPlugin/DatadogLogsPlugin. It's only ever overwritten when a mapper isattached — never cleared. When a Flutter engine detaches (app
backgrounded and killed, hot restart, or Activity recreation on a
config change), that static field keeps pointing at a jnigen-generated
JNI proxy tied to the now-destroyed engine's Dart isolate.
dd-sdk-android's RUM/Logs core is itself a process-wide singleton withbackground writer/upload threads that outlive any single Flutter
engine. When one of those threads serializes a queued event and calls
into the stale mapper, it crashes inside
CallObjectMethod— ause-after-detach JNI reference, invoked from a background thread. The
deterministic crash offset is the fingerprint of this exact failure
mode (a fixed-layout call into freed memory), rather than random heap
corruption.
Change
detachFromEngine()in bothDatadogRumPluginandDatadogLogsPluginnow clears the static mapper's
eventMapperfield.DatadogRumEventMapper.eventMapper/DatadogLogEventMapper.eventMappermarked
@Volatile, so the clear is guaranteed visible to whateverbackground thread might be racing to read it.
DatadogRumPluginTest) asserting the mapperis null after
detachFromEngine().Unreleased.Testing
due to a Flutter/Gradle toolchain version mismatch unrelated to this
change (fails identically on unmodified
develop). Needs a real CI runbefore merge.
Refs: RUMS-6227
🤖 Generated with Claude Code