Reimplement UnhollowedAssembliesPath config option as IL2CPPInteropAssembliesPath (#734)

Author: Kokaiinum

Runtimes/Unity/BepInEx.Unity.IL2CPP/Il2CppInteropManager.cs

@@ -79,8 +79,20 @@ static Il2CppInteropManager()
      false,
      "If enabled, BepInEx will save dummy assemblies generated by an Cpp2IL dumper into BepInEx/dummy.");
 
+    private static readonly ConfigEntry<string> IL2CPPInteropAssembliesPath = ConfigFile.CoreConfig.Bind(
+     "IL2CPP", "IL2CPPInteropAssembliesPath",
+     "{BepInEx}",
+     new StringBuilder()
+         .AppendLine("The path to the folder where IL2CPPInterop assemblies are stored.")
+         .AppendLine("Supports the following placeholders:")
+         .AppendLine("{BepInEx} - Path to the BepInEx folder.")
+         .AppendLine("{ProcessName} - Name of the current process")
+         .ToString());
+
     private static readonly ManualLogSource Logger = BepInEx.Logging.Logger.CreateLogSource("InteropManager");
 
+    private static string il2cppInteropBasePath;
+
     private static bool initialized;
 
     public static string GameAssemblyPath => Environment.GetEnvironmentVariable("BEPINEX_GAME_ASSEMBLY_PATH") ??
@@ -89,9 +101,20 @@ static Il2CppInteropManager()
 
     private static string HashPath => Path.Combine(IL2CPPInteropAssemblyPath, "assembly-hash.txt");
 
-    private static string UnityBaseLibsDirectory => Path.Combine(Paths.BepInExRootPath, "unity-libs");
+    private static string IL2CPPBasePath {
+        get {
+            if (il2cppInteropBasePath != null)
+                return il2cppInteropBasePath;
+            var path = Utility.GetCommandLineArgValue("--unhollowed-path") ?? IL2CPPInteropAssembliesPath.Value;
+            il2cppInteropBasePath = path.Replace("{BepInEx}", Paths.BepInExRootPath)
+                                     .Replace("{ProcessName}", Paths.ProcessName);
+            return il2cppInteropBasePath;
+        }
+    }
+
+    private static string UnityBaseLibsDirectory => Path.Combine(IL2CPPBasePath, "unity-libs");
 
-    internal static string IL2CPPInteropAssemblyPath => Path.Combine(Paths.BepInExRootPath, "interop");
+    internal static string IL2CPPInteropAssemblyPath => Path.Combine(IL2CPPBasePath, "interop");
 
     private static ILoggerFactory LoggerFactory { get; } = MSLoggerFactory.Create(b =>
     {