Fix emulator freeze after iOS auto screen lock#66
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On iOS Safari, an auto screen lock can leave the AudioContext with state === "running" while the ScriptProcessor's onaudioprocess callback permanently stops firing. The emulator's audio buffer then stays full, audioUnderrunAdjustment() throttles CPUCyclesTotal down to 0 cycles per timer iteration, and emulation appears frozen with all inputs unresponsive even though the core setInterval is still ticking. This reuses the existing watchdog primitive that was already in place to recover Firefox/Mac OS X's "node randomly stops playing" bug -- the recovery path (XAudioJSWebAudioWatchDogLast is updated from inside the audio callback, so timeDiff > 500ms is a reliable "node is dead" signal) applies equally to the iOS case. Two tiny changes: - Drop the Gecko-only userAgent gate so the watchdog runs everywhere. - Treat the iOS-specific state name "interrupted" the same as "suspended" so the context gets resumed on lock release too. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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Summary
On iOS Safari, an auto screen lock leaves the
AudioContextreportingstate === 'running'while theScriptProcessorcallback permanently stops firing. The audio buffer stays full,audioUnderrunAdjustment()throttlesCPUCyclesTotaldown to 0, and the emulator looks frozen on resume.The existing
setupWebAudiowatchdog (originally for the Firefox/macOS scriptnode bug) already has the right recovery:XAudioJSWebAudioWatchDogLastis updated from inside the audio callback, sotimeDiff > 500msis a generic "node is dead" signal — it was just gated to Gecko. Two changes inmodules/XAudioJS/XAudioServer.js:navigator.userAgent.indexOf('Gecko/')gate so the watchdog runs everywhere.state === 'interrupted'the same as'suspended'for context resume.Net: +8 / −9 lines, single file.
iOS requires a user gesture to actually re-activate audio, so the user still has to tap once after unlock — but that single tap then reliably unsticks playback.
Test plan