NativeAPI - generateTypeTreeNodesJson - use only jsonPtr without returning array length

Author: K0lb3

TypeTreeGeneratorAPI/NativeAPI.cs

@@ -104,7 +104,7 @@ public static int TypeTreeGenerator_delete(IntPtr typeTreeGeneratorPtr)
         }
 
         [UnmanagedCallersOnly(EntryPoint = "TypeTreeGenerator_generateTreeNodesJson")]
-        public static int TypeTreeGenerator_generateTypeTreeNodesJson(IntPtr typeTreeGeneratorPtr, IntPtr assemblyNamePtr, IntPtr fullNamePtr, IntPtr jsonAddr, IntPtr jsonLength)
+        public static int TypeTreeGenerator_generateTypeTreeNodesJson(IntPtr typeTreeGeneratorPtr, IntPtr assemblyNamePtr, IntPtr fullNamePtr, IntPtr jsonAddr)
         {
             string? assemblyName = Marshal.PtrToStringUTF8(assemblyNamePtr);
             string? fullName = Marshal.PtrToStringUTF8(fullNamePtr);
@@ -123,18 +123,7 @@ public static int TypeTreeGenerator_generateTypeTreeNodesJson(IntPtr typeTreeGen
                     return -1;
                 }
                 var json = TypeTreeNodeSerializer.ToJson(typeTreeNodes!);
-                var jsonBytes = System.Text.Encoding.UTF8.GetBytes(json);
-
-                // Allocate memory for the JSON string
-                IntPtr jsonPtr = Marshal.AllocCoTaskMem(jsonBytes.Length);
-                Marshal.Copy(jsonBytes, 0, jsonPtr, jsonBytes.Length);
-
-                // Write the JSON pointer to the address specified by `jsonAddr`
-                Marshal.WriteIntPtr(jsonAddr, jsonPtr);
-
-                // Write the JSON length to the address specified by `jsonLength`
-                Marshal.WriteInt32(jsonLength, jsonBytes.Length);
-
+                Marshal.WriteIntPtr(jsonAddr, Marshal.StringToCoTaskMemUTF8(json));
                 return 0;
             }
             catch

bindings/python/TypeTreeGeneratorAPI/TypeTreeGenerator.py

@@ -68,8 +68,7 @@ def init_dll():
         ctypes.c_void_p,
         ctypes.c_char_p,
         ctypes.c_char_p,
-        ctypes.c_void_p,
-        ctypes.c_void_p,
+        ctypes.POINTER(ctypes.c_char_p),
     ]
     dll.TypeTreeGenerator_generateTreeNodesRaw.argtypes = [
         ctypes.c_void_p,
@@ -119,19 +118,14 @@ def load_il2cpp(self, il2cpp: bytes, metadata: bytes):
 
     def get_nodes_as_json(self, assembly: str, fullname: str) -> str:
         jsonPtr = ctypes.c_char_p()
-        jsonLen = ctypes.c_int()
         assert not DLL.TypeTreeGenerator_generateTreeNodesJson(
             self.ptr,
             assembly.encode("ascii"),
             fullname.encode("ascii"),
             ctypes.byref(jsonPtr),
-            ctypes.byref(jsonLen),
         ), "failed to dump nodes as json"
-        data = jsonPtr.value
-        assert data and len(data) != jsonLen.value, (
-            "returned json data has an unexpected length"
-        )
-        json_str = data.decode("utf8")
+        assert jsonPtr.value is not None, "didn't write json to ptr"
+        json_str = jsonPtr.value.decode("utf8")
         DLL.FreeCoTaskMem(jsonPtr)
         return json_str