Hackfix our way around MonoModder BS

EverestAPI · Sep 6, 2023 · 3b60666 · 3b60666
1 parent 06e85f6
commit 3b60666
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Showing 3 changed files with 53 additions and 8 deletions.
diff --git a/Celeste.Mod.mm/Mod/Helpers/LegacyMonoMod/Misc.cs b/Celeste.Mod.mm/Mod/Helpers/LegacyMonoMod/Misc.cs
@@ -1,3 +1,4 @@
+using Mono.Cecil;
 using Mono.Cecil.Cil;
 using MonoMod;
 using MonoMod.Cil;
@@ -24,13 +25,8 @@ public static void Uninitialize() {
     }
 
     public static class ILShims {
-        [RelinkLegacyMonoMod("Mono.Cecil.Cil.Instruction MonoMod.Cil.ILLabel::Target")]
-        public static Instruction ILLabel_GetTarget(ILLabel label) => label.Target; // This previously used to be a field
-
-        [RelinkLegacyMonoMod("System.Int32 MonoMod.Cil.ILCursor::AddReference<T>()")]
+        //Relinking is done using a MonoModder hackfix because the methods are generic ._.
         public static int ILCursor_AddReference<T>(ILCursor cursor, T t) => cursor.AddReference(in t); // Reorg expects an in-argument
-
-        [RelinkLegacyMonoMod("System.Int32 MonoMod.Cil.ILCursor::EmitReference<T>()")]
         public static int ILCursor_EmitReference<T>(ILCursor cursor, T t) => cursor.EmitReference(in t); // Reorg expects an in-argument
     }
 
@@ -114,4 +110,44 @@ public static void ReportMonoModCrime(string descr, Assembly perpetrator) {
         }
 
     }
+}
+
+namespace MonoMod {
+    partial class MonoModRules {
+        private static void SetupLegacyMonoModPatcherHackfixes(MonoModder modder) {
+            // Dear MonoMod.Patcher,
+            // What the f*ck is this supposed to be!?!?!?
+            // Sincerely, me :)
+            // (yes this tells MonoMod to relink ILLabel::Target to ILLabel::Target, and yes this is required)
+            modder.RelinkMap["Mono.Cecil.Cil.Instruction MonoMod.Cil.ILLabel::Target"] = new RelinkMapEntry("MonoMod.Cil.ILLabel", "Target");
+
+            OnPostProcessMethod += static (modder, method) => {
+                if (!method.HasBody)
+                    return;
+
+                // We have to do our own relinking because who the heck would ever want to relink a generic method???????
+                TypeDefinition ilShimsType = RulesModule.GetType("Celeste.Mod.Helpers.LegacyMonoMod.ILShims");
+                foreach (Instruction instr in method.Body.Instructions) {
+                    if (!(instr.Operand is MethodReference mref))
+                        continue;
+
+                    // Check if this is the correct method
+                    if (!mref.HasThis || !(mref.IsGenericInstance || mref.HasGenericParameters) || mref.Parameters.Count != 1)
+                        continue;
+
+                    if (mref.DeclaringType.FullName != "MonoMod.Cil.ILCursor")
+                        continue;
+
+                    if (mref.Name != "AddReference" && mref.Name != "EmitReference")
+                        continue;
+
+                    if (mref.Parameters[0].ParameterType.IsByReference)
+                        continue;
+
+                    // Relink the reference
+                    instr.Operand = modder.Module.ImportReference(ilShimsType.FindMethod($"ILCursor_{mref.Name}"));
+                }
+            };
+        }
+    }
 }
diff --git a/Celeste.Mod.mm/MonoModRules.Utils.cs b/Celeste.Mod.mm/MonoModRules.Utils.cs
@@ -107,6 +107,9 @@ public static void SetupLegacyMonoModRelinking(MonoModder modder) {
             // Replace assembly references which changed
             ReplaceAssemblyRefs(modder, static asm => asm.Name.Equals("MonoMod"), GetRulesAssemblyRef("MonoMod.Patcher"));
 
+            // Setup MonoMod.Patcher hackfixes (please just let it be rewritten already I have suffered enough ._.)
+            SetupLegacyMonoModPatcherHackfixes(modder);
+
             // Convert all RelinkLegacyMonoMod attributes to MonoModLinkFrom attributes
             foreach (TypeDefinition type in RulesModule.Types)
                 SetupLegacyMonoModRelinking(modder, type);

diff --git a/Celeste.Mod.mm/MonoModRules.cs b/Celeste.Mod.mm/MonoModRules.cs
@@ -119,15 +119,21 @@ private static void PostProcessType(MonoModder modder, TypeDefinition type) {
             if (type.IsCompilerGeneratedEnumerator())
                 FixEnumeratorDecompile(type);
 
-            // Fix short-long opcodes
-            foreach (MethodDefinition method in type.Methods)
+            foreach (MethodDefinition method in type.Methods) {
+                // Run method processors
+                OnPostProcessMethod?.Invoke(modder, method);
+
+                // Fix short-long opcodes
                 method.FixShortLongOps();
+            }
 
             // Post-process nested types
             foreach (TypeDefinition nested in type.NestedTypes)
                 PostProcessType(modder, nested);
         }
 
+        private static event Action<MonoModder, MethodDefinition> OnPostProcessMethod;
+
 #region Commmon Helper Methods
         public static AssemblyName GetRulesAssemblyRef(string name) => Assembly.GetExecutingAssembly().GetReferencedAssemblies().First(asm => asm.Name.Equals(name));