dotnet 使用 Infer# 自动分析代码缺陷

本文告诉大家如何使用 Infer# 开源库配合 GitHub 的 Action 实现自动分析代码缺陷，如找到可空引用或线程安全等问题

这是一个在 GitHub 上完全开源的仓库，请看 https://github.com/microsoft/infersharp

刚好今天收到了 Infer# 发布 1.2 版本博客，请看 Infer# v1.2: Interprocedural Memory Safety Analysis For C# - .NET Blog

关于 GitHub 的 Action 的基础入门请看 dotnet 部署 github 的 Action 进行持续集成

使用的方法非常简单，只需要在 GitHub 的 Action 的配置文件里面添加如下代码

    - name: Run Infer#
      uses: microsoft/infersharpaction@v1.2
      with:
        binary-path: 输出二进制文件夹路径

如我在 https://github.com/dotnet-campus/AsyncWorkerCollection 开源仓库上的配置代码如下

    - name: Run Infer#
      uses: microsoft/infersharpaction@v1.2
      with:
        binary-path: AsyncWorkerCollection/bin/Release/netcoreapp3.1

此输出的二进制文件夹路径里面要求是包含 dll 和 pdb 文件，通过 dll 进行分析，通过 pdb 从而告诉你是哪个文件

效果如下

可以看到输出了资源没有释放和线程安全问题

Found 3 issues
                        Issue Type(ISSUED_TYPE_ID): #
  Thread Safety Violation(THREAD_SAFETY_VIOLATION): 2
        Dotnet Resource Leak(DOTNET_RESOURCE_LEAK): 1

Analysis Result
==================================================
#0
/home/runner/work/AsyncWorkerCollection/AsyncWorkerCollection/AsyncWorkerCollection/AsyncTaskQueue_/AsyncTaskQueue.cs:72: error: Dotnet Resource Leak
  Leaked { n$1 -> 1 } resource(s) in method "AwaitableTask AsyncTaskQueue.GetExecutableTask(Action)" at type(s) System.Threading.Tasks.Task.

#1
/home/runner/work/AsyncWorkerCollection/AsyncWorkerCollection/AsyncWorkerCollection/DoubleBuffer_/DoubleBufferLazyInitializeTask.cs:47: warning: Thread Safety Violation
  Unprotected write. Non-private method `DoubleBufferLazyInitializeTask`1<T>.OnInitialized()` writes to field `this.dotnetCampus.Threading.DoubleBufferLazyInitializeTask`1<T>._isInitialized` outside of synchronization.
 Reporting because this access may occur on a background thread.

#2
/home/runner/work/AsyncWorkerCollection/AsyncWorkerCollection/AsyncWorkerCollection/DoubleBuffer_/DoubleBufferLazyInitializeTask.cs:41: warning: Thread Safety Violation
  Read/Write race. Non-private method `DoubleBufferLazyInitializeTask`1<T>.OnInitialized()` reads without synchronization from `this.dotnetCampus.Threading.DoubleBufferLazyInitializeTask`1<T>._isInitialized`. Potentially races with write in method `DoubleBufferLazyInitializeTask`1<T>.OnInitialized()`.
 Reporting because this access may occur on a background thread.

Found 3 issues
                        Issue Type(ISSUED_TYPE_ID): #
  Thread Safety Violation(THREAD_SAFETY_VIOLATION): 2
        Dotnet Resource Leak(DOTNET_RESOURCE_LEAK): 1

此工具只能在 Linux 下运行，官方有制作好一个 docker 文件，可以从 https://github.com/microsoft/infersharpaction 拉到。但是问题不大，因为此工具是对输出文件进行分析的，所以可以在 Windows 平台上进行构建，只是将输出的二进制文件使用此工具

在现有的仓库加添加此工具的例子请看 https://github.com/dotnet-campus/AsyncWorkerCollection/pull/66