Gilles Muller

Stefanus Agus Haryono, Ferdian Thung, David Lo et al.

Android operating system (OS) is often updated, where each new version may involve API deprecation. Usages of deprecated APIs in Android apps need to be updated to ensure the apps' compatibility with the old and new versions of Android OS. In this work, we propose AndroEvolve, an automated tool to update usages of deprecated Android APIs, that addresses the limitations of the state-of-the-art tool, CocciEvolve. AndroEvolve utilizes data flow analysis to solve the problem of out-of-method-boundary variables, and variable denormalization to remove the temporary variables introduced by CocciEvolve. We evaluated the accuracy of AndroEvolve using a dataset of 360 target files and 20 deprecated Android APIs, where AndroEvolve is able to produce 319 correct updates, compared to CocciEvolve which only produces 249 correct updates. We also evaluated the readability of AndroEvolve's update results using a manual and an automatic evaluation. Both evaluations demonstrated that the code produced by AndroEvolve has higher readability than CocciEvolve's. A video demonstration of AndroEvolve is available at https://youtu.be/siU0tuMITXI.

Stefanus A. Haryono, Ferdian Thung, David Lo et al.

The Android operating system is frequently updated, with each version bringing a new set of APIs. New versions may involve API deprecation; Android apps using deprecated APIs need to be updated to ensure the apps' compatibility withold and new versions of Android. Updating deprecated APIs is a time-consuming endeavor. Hence, automating the updates of Android APIs can be beneficial for developers. CocciEvolve is the state-of-the-art approach for this automation. However, it has several limitations, including its inability to resolve out-of-method-boundary variables and the low code readability of its update due to the addition of temporary variables. In an attempt to further improve the performance of automated Android API update, we propose an approach named AndroEvolve, which addresses the limitations of CocciEvolve through the addition of data flow analysis and variable name denormalization. Data flow analysis enables AndroEvolve to resolve the value of any variable within the file scope. Variable name denormalization replaces temporary variables that may present in the CocciEvolve update with appropriate values in the target file. We have evaluated the performance of AndroEvolve and the readability of its updates on 360 target files. AndroEvolve produces 26.90% more instances of correct updates compared to CocciEvolve. Moreover, our manual and automated evaluation shows that AndroEvolve updates are more readable than CocciEvolve updates.

Stefanus Agus Haryono, Ferdian Thung, Hong Jin Kang et al.

Due to the deprecation of APIs in the Android operating system,developers have to update usages of the APIs to ensure that their applications work for both the past and current versions of Android.Such updates may be widespread, non-trivial, and time-consuming. Therefore, automation of such updates will be of great benefit to developers. AppEvolve, which is the state-of-the-art tool for automating such updates, relies on having before- and after-update examples to learn from. In this work, we propose an approach named CocciEvolve that performs such updates using only a single after-update example. CocciEvolve learns edits by extracting the relevant update to a block of code from an after-update example. From preliminary experiments, we find that CocciEvolve can successfully perform 96 out of 112 updates, with a success rate of 85%.

Nicolas Palix, Gaël Thomas, Suman Saha et al.

In August 2011, Linux entered its third decade. Ten years before, Chou et al. published a study of faults found by applying a static analyzer to Linux versions 1.0 through 2.4.1. A major result of their work was that the drivers directory contained up to 7 times more of certain kinds of faults than other directories. This result inspired numerous efforts on improving the reliability of driver code. Today, Linux is used in a wider range of environments, provides a wider range of services, and has adopted a new development and release model. What has been the impact of these changes on code quality? To answer this question, we have transported Chou et al.'s experiments to all versions of Linux 2.6; released between 2003 and 2011. We find that Linux has more than doubled in size during this period, but the number of faults per line of code has been decreasing. Moreover, the fault rate of drivers is now below that of other directories, such as arch. These results can guide further development and research efforts for the decade to come. To allow updating these results as Linux evolves, we define our experimental protocol and make our checkers available.