First run now makes sure permissions are workable

IPA.Injector/IPA.Injector.csproj

@@ -56,6 +56,7 @@
     <Compile Include="Backups\BackupUnit.cs" />
     <Compile Include="Bootstrapper.cs" />
     <Compile Include="Injector.cs" />
+    <Compile Include="PermissionFix.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="Updates.cs" />
     <Compile Include="Virtualizer.cs" />

IPA.Injector/Injector.cs

@@ -19,6 +19,7 @@ namespace IPA.Injector
     public static class Injector
     {
         private static Task pluginAsyncLoadTask;
+        private static Task permissionFixTask;
 
         // ReSharper disable once UnusedParameter.Global
         public static void Main(string[] args)
@@ -62,6 +63,7 @@ namespace IPA.Injector
                 LibLoader.SetupAssemblyFilenames(true);
 
                 pluginAsyncLoadTask = PluginLoader.LoadTask();
+                permissionFixTask = PermissionFix.FixPermissions(new DirectoryInfo(Environment.CurrentDirectory));
             }
             catch (Exception e)
             {
@@ -264,6 +266,7 @@ namespace IPA.Injector
         {
             // wait for plugins to finish loading
             pluginAsyncLoadTask.Wait();
+            permissionFixTask.Wait();
             log.Debug("Plugins loaded");
             log.Debug(string.Join(", ", PluginLoader.PluginsMetadata));
             PluginComponent.Create();

IPA.Injector/PermissionFix.cs

@@ -0,0 +1,65 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Security.AccessControl;
+using System.Security.Principal;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace IPA.Injector
+{
+    internal static class PermissionFix
+    {
+        public static Task FixPermissions(DirectoryInfo root)
+        {
+            if (!root.Exists) return Task.CompletedTask;
+
+            return Task.Run(() =>
+            {
+                try
+                {
+                    var acl = root.GetAccessControl();
+
+                    var rules = acl.GetAccessRules(true, true, typeof(SecurityIdentifier));
+
+                    var requestedRights = FileSystemRights.Modify;
+                    var requestedInheritance = InheritanceFlags.ContainerInherit | InheritanceFlags.ObjectInherit;
+                    var requestedPropagation = PropagationFlags.InheritOnly;
+
+                    bool hasRule = false;
+                    for (var i = 0; i < rules.Count; i++)
+                    {
+                        var rule = rules[i];
+
+                        if (rule is FileSystemAccessRule fsrule
+                            && fsrule.AccessControlType == AccessControlType.Allow
+                            && fsrule.InheritanceFlags.HasFlag(requestedInheritance)
+                            && fsrule.PropagationFlags == requestedPropagation
+                            && fsrule.FileSystemRights.HasFlag(requestedRights))
+                        { hasRule = true; break; }
+                    }
+
+                    if (!hasRule)
+                    { // this is *sooo* fucking slow on first run
+                        acl.AddAccessRule(
+                            new FileSystemAccessRule(
+                                new SecurityIdentifier(WellKnownSidType.WorldSid, null),
+                                requestedRights,
+                                requestedInheritance,
+                                requestedPropagation,
+                                AccessControlType.Allow
+                            )
+                        );
+                        root.SetAccessControl(acl);
+                    }
+                }
+                catch (Exception e)
+                {
+                    Logging.Logger.log.Warn("Error configuring permissions in the game install dir");
+                    Logging.Logger.log.Warn(e);
+                }
+            });
+        }
+    }
+}