diff --git a/src/coverlet.core/Instrumentation/ModuleTrackerTemplate.cs b/src/coverlet.core/Instrumentation/ModuleTrackerTemplate.cs new file mode 100644 index 0000000..064361b --- /dev/null +++ b/src/coverlet.core/Instrumentation/ModuleTrackerTemplate.cs @@ -0,0 +1,73 @@ +using System; +using System.IO; +using System.Threading; + +namespace Coverlet.Core.Instrumentation +{ + /// + /// This static class will be injected on a module being instrumented in order to direct on module hits + /// 'to a single location. + /// + /// + /// As this type is going to be customized on each module it doesn't follow typical practices regarding + /// visibility of members, etc. + /// + public static class ModuleTrackerTemplate + { + public static string HitsFilePath; + + public readonly static int[] HitsArray; + + static ModuleTrackerTemplate() + { + AppDomain.CurrentDomain.ProcessExit += new EventHandler(UnloadModule); + AppDomain.CurrentDomain.DomainUnload += new EventHandler(UnloadModule); + // At the end of the instrumentation of a module, the instrumenter needs to add code here + // to initialize the static fields according to the values derived from the instrumentation of + // the module. + } + + public static void UnloadModule(object sender, EventArgs e) + { + // TODO: same module can be unloaded multiple times in the same process. Need to check and handle this case. + // TODO: perhaps some kind of global mutex based on the name of the modules hits file, and after the first + // TODO: they update the hit count from the file already created. Something like this, (minus the read stuff): + using (var mutex = new Mutex(true, Path.GetFileNameWithoutExtension(HitsFilePath) + "_Mutex", out bool createdNew)) + { + if (!createdNew) + mutex.WaitOne(); + + if (!File.Exists(HitsFilePath)) + { + // File not created yet, just write it + using (var fs = new FileStream(HitsFilePath, FileMode.Create)) + using (var bw = new BinaryWriter(fs)) + { + bw.Write(HitsArray.Length); + foreach (int hitCount in HitsArray) + { + bw.Write(hitCount); + } + } + } + else + { + using (var fs = File.Open(HitsFilePath, FileMode.Open)) + using (var br = new BinaryReader(fs)) + using (var bw = new BinaryWriter(fs)) + { + int hitsLength = br.ReadInt32(); + // TODO: check hits length match + + for (int i = 0; i < hitsLength; ++i) + { + int oldHitCount = br.ReadInt32(); + bw.Seek(-sizeof(int), SeekOrigin.Current); + bw.Write(HitsArray[i] + oldHitCount); + } + } + } + } + } + } +}