/// <summary>Returns the methods unmodified list of CodeInstructions</summary>
        /// <param name="original">The original method</param>
        /// <param name="generator">The generator that now contains all local variables and labels contained in the result</param>
        /// <returns>A list containing all the original CodeInstructions</returns>
        public static List <CodeInstruction> GetOriginalInstructions(MethodBase original, out ILGenerator generator)
        {
            var patch = DynamicTools.CreateDynamicMethod(original, $"_Copy{Guid.NewGuid()}");

            generator = patch.GetILGenerator();
            var reader = MethodBodyReader.GetInstructions(generator, original);

            return(reader.Select(ins => ins.GetCodeInstruction()).ToList());
        }
Beispiel #2
0
        public static DynamicMethod CreatePatchedMethod(MethodBase original, MethodBase source, string harmonyInstanceID, List <MethodInfo> prefixes, List <MethodInfo> postfixes, List <MethodInfo> transpilers, List <MethodInfo> finalizers)
        {
            try
            {
                if (original == null)
                {
                    throw new ArgumentNullException(nameof(original));
                }

                Memory.MarkForNoInlining(original);

                if (Harmony.DEBUG)
                {
                    FileLog.LogBuffered("### Patch " + original.FullDescription());
                    FileLog.FlushBuffer();
                }

                var idx = prefixes.Count() + postfixes.Count() + finalizers.Count();
                var firstArgIsReturnBuffer = NativeThisPointer.NeedsNativeThisPointerFix(original);
                var returnType             = AccessTools.GetReturnedType(original);
                var hasFinalizers          = finalizers.Any();
                var patch = DynamicTools.CreateDynamicMethod(original, "_Patch" + idx);
                if (patch == null)
                {
                    return(null);
                }

                var il = patch.GetILGenerator();

                var originalVariables = DynamicTools.DeclareLocalVariables(source ?? original, il);
                var privateVars       = new Dictionary <string, LocalBuilder>();

                LocalBuilder resultVariable = null;
                if (idx > 0)
                {
                    resultVariable          = DynamicTools.DeclareLocalVariable(il, returnType);
                    privateVars[RESULT_VAR] = resultVariable;
                }

                prefixes.Union(postfixes).Union(finalizers).ToList().ForEach(fix =>
                {
                    if (privateVars.ContainsKey(fix.DeclaringType?.FullName ?? "") == false)
                    {
                        fix.GetParameters()
                        .Where(patchParam => patchParam.Name == STATE_VAR)
                        .Do(patchParam =>
                        {
                            var privateStateVariable = DynamicTools.DeclareLocalVariable(il, patchParam.ParameterType);
                            privateVars[fix.DeclaringType?.FullName ?? ""] = privateStateVariable;
                        });
                    }
                });

                LocalBuilder finalizedVariable = null;
                if (hasFinalizers)
                {
                    finalizedVariable = DynamicTools.DeclareLocalVariable(il, typeof(bool));

                    privateVars[EXCEPTION_VAR] = DynamicTools.DeclareLocalVariable(il, typeof(Exception));

                    // begin try
                    Emitter.MarkBlockBefore(il, new ExceptionBlock(ExceptionBlockType.BeginExceptionBlock), out _);
                }

                if (firstArgIsReturnBuffer)
                {
                    Emitter.Emit(il, OpCodes.Ldarg_1);                     // load ref to return value
                }
                var skipOriginalLabel = il.DefineLabel();
                var canHaveJump       = AddPrefixes(il, original, prefixes, privateVars, skipOriginalLabel);

                var copier = new MethodCopier(source ?? original, il, originalVariables);
                foreach (var transpiler in transpilers)
                {
                    copier.AddTranspiler(transpiler);
                }
                if (firstArgIsReturnBuffer)
                {
                    copier.AddTranspiler(NativeThisPointer.m_ArgumentShiftTranspiler);
                }

                var endLabels = new List <Label>();
                copier.Finalize(endLabels);

                foreach (var label in endLabels)
                {
                    Emitter.MarkLabel(il, label);
                }
                if (resultVariable != null)
                {
                    Emitter.Emit(il, OpCodes.Stloc, resultVariable);
                }
                if (canHaveJump)
                {
                    Emitter.MarkLabel(il, skipOriginalLabel);
                }

                AddPostfixes(il, original, postfixes, privateVars, false);

                if (resultVariable != null)
                {
                    Emitter.Emit(il, OpCodes.Ldloc, resultVariable);
                }

                AddPostfixes(il, original, postfixes, privateVars, true);

                if (hasFinalizers)
                {
                    AddFinalizers(il, original, finalizers, privateVars, false);
                    Emitter.Emit(il, OpCodes.Ldc_I4_1);
                    Emitter.Emit(il, OpCodes.Stloc, finalizedVariable);
                    var noExceptionLabel1 = il.DefineLabel();
                    Emitter.Emit(il, OpCodes.Ldloc, privateVars[EXCEPTION_VAR]);
                    Emitter.Emit(il, OpCodes.Brfalse, noExceptionLabel1);
                    Emitter.Emit(il, OpCodes.Ldloc, privateVars[EXCEPTION_VAR]);
                    Emitter.Emit(il, OpCodes.Throw);
                    Emitter.MarkLabel(il, noExceptionLabel1);

                    // end try, begin catch
                    Emitter.MarkBlockBefore(il, new ExceptionBlock(ExceptionBlockType.BeginCatchBlock), out var label);
                    Emitter.Emit(il, OpCodes.Stloc, privateVars[EXCEPTION_VAR]);

                    Emitter.Emit(il, OpCodes.Ldloc, finalizedVariable);
                    var endFinalizerLabel = il.DefineLabel();
                    Emitter.Emit(il, OpCodes.Brtrue, endFinalizerLabel);

                    var rethrowPossible = AddFinalizers(il, original, finalizers, privateVars, true);

                    Emitter.MarkLabel(il, endFinalizerLabel);

                    var noExceptionLabel2 = il.DefineLabel();
                    Emitter.Emit(il, OpCodes.Ldloc, privateVars[EXCEPTION_VAR]);
                    Emitter.Emit(il, OpCodes.Brfalse, noExceptionLabel2);
                    if (rethrowPossible)
                    {
                        Emitter.Emit(il, OpCodes.Rethrow);
                    }
                    else
                    {
                        Emitter.Emit(il, OpCodes.Ldloc, privateVars[EXCEPTION_VAR]);
                        Emitter.Emit(il, OpCodes.Throw);
                    }
                    Emitter.MarkLabel(il, noExceptionLabel2);

                    // end catch
                    Emitter.MarkBlockAfter(il, new ExceptionBlock(ExceptionBlockType.EndExceptionBlock));

                    if (resultVariable != null)
                    {
                        Emitter.Emit(il, OpCodes.Ldloc, resultVariable);
                    }
                }

                if (firstArgIsReturnBuffer)
                {
                    Emitter.Emit(il, OpCodes.Stobj, returnType);                     // store result into ref
                }
                Emitter.Emit(il, OpCodes.Ret);

                if (Harmony.DEBUG)
                {
                    FileLog.LogBuffered("DONE");
                    FileLog.LogBuffered("");
                    FileLog.FlushBuffer();
                }

                DynamicTools.PrepareDynamicMethod(patch);
                return(patch);
            }
            catch (Exception ex)
            {
                var exceptionString = "Exception from HarmonyInstance \"" + harmonyInstanceID + "\" patching " + original.FullDescription() + ": " + ex;
                if (Harmony.DEBUG)
                {
                    var savedIndentLevel = FileLog.indentLevel;
                    FileLog.indentLevel = 0;
                    FileLog.Log(exceptionString);
                    FileLog.indentLevel = savedIndentLevel;
                }

                throw new Exception(exceptionString, ex);
            }
            finally
            {
                if (Harmony.DEBUG)
                {
                    FileLog.FlushBuffer();
                }
            }
        }