HACMony: automatically detecting hopping-related audio-stream conflict issues on HarmonyOS

Abstract

HarmonyOS is emerging as a popular distributed operating system for diverse mobile devices. One of its standout features is app-hopping, which allows users to switch apps seamlessly across different HarmonyOS devices. However, when apps play audio-stream-hop between different devices, they can easily trigger Hopping-related Audio-stream Conflict (\mathsf{\text{HAC}}) scenarios. Improper resolution of \mathsf{\text{HAC}} will lead to significant \mathsf{\text{HAC}} issues, which are hard to detect comprehensively due to the unclear semantics of HarmonyOS’s app-hopping mechanism and the lack of effective multi-app hopping testing methods. To fill the gap, this paper introduces an automated and efficient approach to detecting \mathsf{\text{HAC}} issues. We formalize the operational semantics of HarmonyOS’s app-hopping mechanism for audio streams for the first time. Leveraging this formalization, we design an Audio-stream-aware State Transition Graph (\mathsf{\text{ASTG}}) to model the behaviors of audio-streams during window transitions and propose a model-based approach to detect \mathsf{\text{HAC}} issues automatically. Our techniques are implemented in a tool, \mathsf{\text{HACMony}}, and evaluated on 20 real-world HarmonyOS apps. Experimental results reveal that 12 of the 20 apps exhibit \mathsf{\text{HAC}} issues. Among the 53 \mathsf{\text{HAC}} issues detected, a total of 18 unique \mathsf{\text{HAC}} issues are manually confirmed. Additionally, we summarize the detected issues into two typical types, namely \mathsf{\text{MoD}} and \mathsf{\text{MoR}}, and analyz their characteristics to assist and guide both app and OS developers.

Graphical abstract

Keywords

HarmonyOS / audio-stream conflict / app-hopping / mobile testing / large language model

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