[tools] Add helper tool to create launch.json for dotnet-linker. (#18294

)

This tool takes a binlog as input, and creates a launch.json for dotnet-linker
that will execute the linker as was done in the binlog.

This is very useful for debugging custom linker steps, since they can be
debugged in VSCode now.

tools/create-dotnet-linker-launch-json/Program.cs

@@ -0,0 +1,136 @@
+using System.IO;
+using System.Text;
+
+using Microsoft.Build.Framework;
+using Microsoft.Build.Logging;
+using Microsoft.Build.Logging.StructuredLogger;
+
+using Mono.Options;
+
+class Program {
+	static int Main (string [] args)
+	{
+		var printHelp = false;
+		var binlog = string.Empty;
+		var rootDirectory = string.Empty;
+		var skippedLinkerCommands = 0;
+		var options = new OptionSet {
+			{ "h|?|help", "Print this help message", (v) => printHelp = true },
+			{ "r|root=", "The root directory", (v) => rootDirectory = v },
+			{ "bl|binlog=", "The binlog", (v) => binlog = v },
+			{ "s|skip", "Task invocations to skip", (v) => skippedLinkerCommands++ },
+		};
+
+		if (printHelp) {
+			options.WriteOptionDescriptions (Console.Out);
+			return 0;
+		}
+
+		var others = options.Parse (args);
+		if (others.Any ()) {
+			Console.WriteLine ("Unexpected arguments:");
+			foreach (var arg in others)
+				Console.WriteLine ("\t{0}", arg);
+			Console.WriteLine ("Expected arguments are:");
+			options.WriteOptionDescriptions (Console.Out);
+			return 1;
+		}
+
+		if (string.IsNullOrEmpty (binlog)) {
+			Console.Error.WriteLine ("A binlog is required");
+			Console.WriteLine ("Expected arguments are:");
+			options.WriteOptionDescriptions (Console.Out);
+			return 1;
+		}
+
+		var path = Path.GetFullPath (binlog);
+
+		if (string.IsNullOrEmpty (rootDirectory))
+			rootDirectory = Path.GetDirectoryName (path)!;
+
+		Console.WriteLine ($"Processing {path} with root directory {rootDirectory}...");
+
+
+		var reader = new BinLogReader ();
+		var records = reader.ReadRecords (path).ToArray ();
+		foreach (var record in records) {
+			if (record is null)
+				continue;
+
+			if (record.Args is null)
+				continue;
+
+			if (record.Args is TaskStartedEventArgs tsea && tsea.TaskName == "ILLink") {
+				if (skippedLinkerCommands > 0) {
+					Console.WriteLine ($"Skipped an ILLink task invocation, {skippedLinkerCommands} left to skip...");
+					skippedLinkerCommands--;
+					continue;
+				}
+
+
+				var relevantRecords = records.Where (v => v?.Args?.BuildEventContext?.TaskId == tsea.BuildEventContext.TaskId).Select (v => v.Args).ToArray ();
+				var cla = relevantRecords.Where (v => v is BuildMessageEventArgs).Cast<BuildMessageEventArgs> ().Where (v => v?.ToString ()?.Contains ("CommandLineArguments") == true).ToArray ();
+				foreach (var rr in relevantRecords) {
+					if (rr is TaskCommandLineEventArgs tclea) {
+						if (!Xamarin.Utils.StringUtils.TryParseArguments (tclea.CommandLine.Replace ('\n', ' '), out var arguments, out var ex)) {
+							Console.WriteLine ($"Failed to parse command line arguments: {ex.Message}");
+							return 1;
+						}
+
+						WriteLaunchJson (CreateLaunchJson (rootDirectory, arguments));
+						return 0;
+					}
+				}
+			}
+		}
+
+		Console.Error.WriteLine ($"Unable to find command line arguments for ILLink in {path}");
+		return 1;
+	}
+
+	static void WriteLaunchJson (string contents)
+	{
+		var dir = Environment.CurrentDirectory!;
+		while (!Directory.Exists (Path.Combine (dir, "tools", "dotnet-linker")))
+			dir = Path.GetDirectoryName (dir)!;
+		var path = Path.Combine (dir, "tools", "dotnet-linker", ".vscode", "launch.json");
+		File.WriteAllText (path, contents);
+		Console.WriteLine ($"Created {path}");
+	}
+
+	static string CreateLaunchJson (string workingDirectory, string [] arguments)
+	{
+		var dotnet = arguments [0];
+		var sb = new StringBuilder ();
+		sb.AppendLine ("{");
+		sb.AppendLine ("    // Use IntelliSense to learn about possible attributes.");
+		sb.AppendLine ("    // Hover to view descriptions of existing attributes.");
+		sb.AppendLine ("    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387");
+		sb.AppendLine ("    \"version\": \"0.2.0\",");
+		sb.AppendLine ("    \"configurations\": [");
+		sb.AppendLine ("        {");
+		sb.AppendLine ("            \"justMyCode\": false,");
+		sb.AppendLine ("            \"preLaunchTask\": \"make\",");
+		sb.AppendLine ("            \"name\": \".NET Core Launch (console)\",");
+		sb.AppendLine ("            \"type\": \"coreclr\",");
+		sb.AppendLine ("            \"request\": \"launch\",");
+		sb.AppendLine ($"            \"program\": \"{dotnet}\",");
+		sb.AppendLine ("            \"args\": [");
+		for (var i = 1; i < arguments.Length; i++) {
+			sb.AppendLine ($"                \"{arguments [i]}\"{(i < arguments.Length - 1 ? "," : "")}");
+		}
+		sb.AppendLine ("            ],");
+		sb.AppendLine ($"            \"cwd\": \"{Path.GetFullPath (workingDirectory)}\",");
+		sb.AppendLine ("            \"console\": \"internalConsole\",");
+		sb.AppendLine ("            \"stopAtEntry\": false");
+		sb.AppendLine ("        },");
+		sb.AppendLine ("        {");
+		sb.AppendLine ("            \"name\": \".NET Core Attach\",");
+		sb.AppendLine ("            \"type\": \"coreclr\",");
+		sb.AppendLine ("            \"request\": \"attach\"");
+		sb.AppendLine ("        }");
+		sb.AppendLine ("    ]");
+		sb.AppendLine ("}");
+		return sb.ToString ();
+	}
+}

tools/create-dotnet-linker-launch-json/README.md

@@ -0,0 +1,3 @@
+This tool takes a binlog that executes dotnet-linker, and creates a
+launch.json file for the dotnet-linker directory so that the steps can be
+debugged in VSCode.

tools/create-dotnet-linker-launch-json/create-dotnet-linker-launch-json.csproj

@@ -0,0 +1,21 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net7.0</TargetFramework>
+    <RootNamespace>create_dotnet_linker_launch_json</RootNamespace>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="MSBuild.StructuredLogger" Version="2.1.758" />
+    <PackageReference Include="Mono.Options" Version="6.12.0.148" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Compile Include="..\common\StringUtils.cs">
+      <Link>StringUtils.cs</Link>
+    </Compile>
+  </ItemGroup>
+</Project>

tools/create-dotnet-linker-launch-json/create-dotnet-linker-launch-json.sln

@@ -0,0 +1,25 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 16
+VisualStudioVersion = 25.0.1706.0
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "create-dotnet-linker-launch-json", "create-dotnet-linker-launch-json.csproj", "{9D626D84-80BA-43E8-ADDF-EAE8944F73D8}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{9D626D84-80BA-43E8-ADDF-EAE8944F73D8}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{9D626D84-80BA-43E8-ADDF-EAE8944F73D8}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{9D626D84-80BA-43E8-ADDF-EAE8944F73D8}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{9D626D84-80BA-43E8-ADDF-EAE8944F73D8}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {B197B398-E8C7-444F-B2E2-1F479AE20CA2}
+	EndGlobalSection
+EndGlobal