private static bool PatchUnityExe(string managedDir, string unityOutputDLL, out string message)
{
message = null;
try
{
var injectedDLL = Path.GetFullPath($"{managedDir}\\BepInEx.Bootstrap.dll");
File.WriteAllBytes(injectedDLL, EmbeddedResource.Get("BepInEx.Patcher.BepInEx.Bootstrap.dll"));
var defaultResolver = new DefaultAssemblyResolver();
defaultResolver.AddSearchDirectory(managedDir);
var rp = new ReaderParameters
{
AssemblyResolver = defaultResolver
};
var unityBackupDLL = $"{GetUnityEngineAssembly(managedDir)}.bak";
//determine which assembly to use as a base
var unity = AssemblyDefinition.ReadAssembly(unityOutputDLL, rp);
if (!VerifyAssembly(unity, out message))
{
//try and fall back to .bak if exists
if (File.Exists(unityBackupDLL))
{
unity.Dispose();
unity = AssemblyDefinition.ReadAssembly(unityBackupDLL, rp);
if (!VerifyAssembly(unity, out message))
{
//can't use anything
unity.Dispose();
message += "\r\nThe backup is not usable.";
return(false);
}
}
else
{
//can't use anything
unity.Dispose();
message += "\r\nNo backup exists.";
return(false);
}
}
else
{
//make a backup of the assembly
File.Copy(unityOutputDLL, unityBackupDLL, true);
unity.Dispose();
unity = AssemblyDefinition.ReadAssembly(unityBackupDLL, rp);
}
//patch
using (unity)
using (var injected = AssemblyDefinition.ReadAssembly(injectedDLL, rp))
{
InjectAssembly(unity, injected);
unity.Write(unityOutputDLL);
}
}
catch (Exception e)
{
message = e.ToString();
return(false);
}
return(true);
}
