So apparently field offsets are in the metadata registration. Who kne…

…w? not me.
SamboyCoding · Jan 22, 2021 · 75f9cd4 · 75f9cd4
1 parent d290cea
commit 75f9cd4
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Showing 3 changed files with 37 additions and 32 deletions.
diff --git a/Cpp2IL/AssemblyBuilder.cs b/Cpp2IL/AssemblyBuilder.cs
@@ -272,7 +272,7 @@ private static List<CppMethodData> ProcessTypeContents(Il2CppMetadata metadata,
             }
 
             //Handle base fields
-            var fieldOffset = baseFields.Aggregate((ulong) (ilTypeDefinition.MetadataType == MetadataType.Class ? 0x10 : 0x0), (currentOffset, baseField) => HandleField(baseField.FieldType, currentOffset, baseField.Name, baseField, ref fields, typeMetaText));
+            // var fieldOffset = baseFields.Aggregate((ulong) (ilTypeDefinition.MetadataType == MetadataType.Class ? 0x10 : 0x0), (currentOffset, baseField) => HandleField(baseField.FieldType, currentOffset, baseField.Name, baseField, ref fields, typeMetaText));
 
             var lastFieldIdx = cppTypeDefinition.firstFieldIdx + cppTypeDefinition.field_count;
             for (var fieldIdx = cppTypeDefinition.firstFieldIdx; fieldIdx < lastFieldIdx; ++fieldIdx)
@@ -299,8 +299,10 @@ private static List<CppMethodData> ProcessTypeContents(Il2CppMetadata metadata,
 
                 if (!fieldDefinition.IsStatic)
                 {
-                    fieldOffset = HandleField(fieldTypeRef, fieldOffset, fieldName, fieldDefinition, ref fields, typeMetaText);
+                    var thisFieldOffset = cppAssembly.GetFieldOffsetFromIndex(cppTypeDefinition.TypeIndex, fieldIdx - cppTypeDefinition.firstFieldIdx, fieldIdx, ilTypeDefinition.IsValueType, fieldDefinition.IsStatic);
 
+                    HandleField(fieldTypeRef, thisFieldOffset, fieldName, fieldDefinition, ref fields, typeMetaText);
+
                     //Add [FieldOffset(Offset = "0xDEADBEEF")]
                     var fieldOffsetAttributeInst = new CustomAttribute(ilTypeDefinition.Module.ImportReference(fieldOffsetAttribute));
                     fieldOffsetAttributeInst.Fields.Add(new CustomAttributeNamedArgument("Offset", new CustomAttributeArgument(stringType, $"0x{fields.Last().Offset:X}")));
@@ -565,18 +567,8 @@ private static List<CppMethodData> ProcessTypeContents(Il2CppMetadata metadata,
             return typeMethods;
         }
 
-        private static ulong HandleField(TypeReference fieldTypeRef, ulong fieldOffset, string fieldName, FieldDefinition fieldDefinition, ref List<FieldInType> fields, StringBuilder typeMetaText)
+        private static void HandleField(TypeReference fieldTypeRef, int fieldOffset, string fieldName, FieldDefinition fieldDefinition, ref List<FieldInType> fields, StringBuilder typeMetaText)
         {
-            var length = Utils.GetSizeOfObject(fieldTypeRef);
-
-            var boundarySize = LibCpp2IlMain.ThePe!.is32Bit ? (decimal) 4 : 8;
-            var fieldEnd = fieldOffset + length - 1;
-            if (Math.Floor(fieldOffset / boundarySize) != Math.Floor(fieldEnd / boundarySize))
-            {
-                //Would cross an alignment boundary, so move to the next alignment.
-                fieldOffset = (ulong) ((Math.Floor(fieldOffset / boundarySize) + 1) * boundarySize);
-            }
-
             //ONE correction. String#start_char is remapped to a char[] not a char because the block allocated for all chars is directly sequential to the length of the string, because that's how c++ works.
             if (fieldDefinition.DeclaringType.FullName == "System.String" && fieldTypeRef.FullName == "System.Char")
                 fieldTypeRef = fieldTypeRef.MakeArrayType();
@@ -585,13 +577,11 @@ private static ulong HandleField(TypeReference fieldTypeRef, ulong fieldOffset,
             {
                 Name = fieldName,
                 Type = fieldTypeRef,
-                Offset = fieldOffset,
+                Offset = (ulong) fieldOffset,
                 Static = fieldDefinition.IsStatic,
                 Constant = fieldDefinition.Constant
             };
 
-            fieldOffset += length;
-
             fields.Add(field);
 
             typeMetaText.Append($"\n\t{(field.Static ? "Static Field" : "Field")}: {field.Name}\n")
@@ -600,7 +590,6 @@ private static ulong HandleField(TypeReference fieldTypeRef, ulong fieldOffset,
 
             if (field.Constant != null)
                 typeMetaText.Append($"\t\tDefault Value: {field.Constant}\n");
-            return fieldOffset;
         }
 
 

diff --git a/Cpp2IL/Program.cs b/Cpp2IL/Program.cs
@@ -161,8 +161,6 @@ public static int Main(string[] args)
                 Console.WriteLine("Initialization with LibCpp2IL failed.");
                 return 1;
             }
-
-            Console.WriteLine(LibCpp2IlReflection.GetType("String", "System").DeclaringAssembly.Name);
 
             //Dump DLLs
 

diff --git a/LibCpp2IL/PE/PE.cs b/LibCpp2IL/PE/PE.cs
@@ -637,26 +637,44 @@ public ulong[] GetPointers(ulong pointer, long count)
             return ReadClassArrayAtVirtualAddress<ulong>(pointer, count);
         }
 
-        public long GetFieldOffsetFromIndex(int typeIndex, int fieldIndexInType, int fieldIndex)
+        public int GetFieldOffsetFromIndex(int typeIndex, int fieldIndexInType, int fieldIndex, bool isValueType, bool isStatic)
         {
-            var ptr = fieldOffsets[typeIndex];
-            if (ptr >= 0)
+            try
             {
-                long pos;
-                if (is32Bit)
-                    pos = MapVirtualAddressToRaw((uint) ptr) + 4 * fieldIndexInType;
+                var offset = -1;
+                if (LibCpp2IlMain.MetadataVersion > 21)
+                {
+                    var ptr = (ulong) fieldOffsets[typeIndex];
+                    if (ptr > 0)
+                    {
+                        Position = (long) ((ulong) MapVirtualAddressToRaw(ptr) + 4ul * (ulong)fieldIndexInType);
+                        offset = ReadInt32();
+                    }
+                }
                 else
-                    pos = MapVirtualAddressToRaw((ulong) ptr) + 4 * fieldIndexInType;
-                if (pos <= BaseStream.Length - 4)
                 {
-                    Position = pos;
-                    return ReadInt32();
+                    offset = (int)fieldOffsets[fieldIndex];
                 }
-
+                if (offset > 0)
+                {
+                    if (isValueType && !isStatic)
+                    {
+                        if (is32Bit)
+                        {
+                            offset -= 8;
+                        }
+                        else
+                        {
+                            offset -= 16;
+                        }
+                    }
+                }
+                return offset;
+            }
+            catch
+            {
                 return -1;
             }
-
-            return 0;
         }
 
         public ulong GetMethodPointer(int methodIndex, int methodDefinitionIndex, int imageIndex, uint methodToken)