From 3332e321440a0158f33bd94b069499d802009521 Mon Sep 17 00:00:00 2001
From: zhangyuang <leonin0829@gmail.com>
Date: Sat, 21 Oct 2023 22:19:01 +0800
Subject: [PATCH] fix: struct offset position

---
 src/lib.rs   | 14 +++++++++-----
 src/utils.rs | 29 +++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index 44e8881..03a7fb5 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -6,8 +6,9 @@ use define::{number_to_data_type, DataType, FFIParams, OpenParams, RsArgsValue};
 use napi::bindgen_prelude::*;
 use utils::{
   calculate_layout, create_array_from_pointer, get_data_type_size_align,
-  get_js_function_call_value, js_array_to_number_array, js_array_to_string_array,
-  js_nunmber_to_i32, js_string_to_string, js_unknown_to_data_type, rs_array_to_js_array, ArrayType,
+  get_js_function_call_value, get_rs_value_size_align, js_array_to_number_array,
+  js_array_to_string_array, js_nunmber_to_i32, js_string_to_string, js_unknown_to_data_type,
+  rs_array_to_js_array, ArrayType,
 };
 
 use indexmap::IndexMap;
@@ -311,9 +312,12 @@ fn load(
           };
         }
         RsArgsValue::Object(val) => {
-          let (size, align) = calculate_layout(&val);
-          let layout = if size > 0 && align > 0 {
-            Layout::from_size_align(size, 4).unwrap()
+          let (size, _) = calculate_layout(&val);
+
+          let layout = if size > 0 {
+            let (_, first_field) = val.get_index(0).unwrap();
+            let (_, align) = get_rs_value_size_align(first_field);
+            Layout::from_size_align(size, align).unwrap()
           } else {
             Layout::new::<i32>()
           };
diff --git a/src/utils.rs b/src/utils.rs
index 4b11477..4c5a843 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -112,6 +112,35 @@ pub fn calculate_layout(map: &IndexMap<String, RsArgsValue>) -> (usize, usize) {
   (size, align)
 }
 
+pub fn get_rs_value_size_align(val: &RsArgsValue) -> (usize, usize) {
+  return match val {
+    RsArgsValue::I32(_) => (std::mem::size_of::<i32>(), std::mem::align_of::<i32>()),
+    RsArgsValue::Boolean(_) => (std::mem::size_of::<bool>(), std::mem::align_of::<bool>()),
+    RsArgsValue::String(_) => (
+      std::mem::size_of::<*const c_char>(),
+      std::mem::align_of::<*const c_char>(),
+    ),
+    RsArgsValue::Double(_) => (
+      std::mem::size_of::<c_double>(),
+      std::mem::align_of::<c_double>(),
+    ),
+    RsArgsValue::StringArray(_) => (
+      std::mem::size_of::<*const *const c_char>(),
+      std::mem::align_of::<*const *const c_char>(),
+    ),
+    RsArgsValue::DoubleArray(_) => (
+      std::mem::size_of::<*const c_double>(),
+      std::mem::align_of::<*const c_double>(),
+    ),
+    RsArgsValue::I32Array(_) => (
+      std::mem::size_of::<*const c_int>(),
+      std::mem::align_of::<*const c_int>(),
+    ),
+    _ => {
+      panic!("get_rs_value_size_align error")
+    }
+  };
+}
 pub fn get_data_type_size_align(data_type: DataType) -> (usize, usize) {
   return match data_type {
     DataType::I32 => (std::mem::size_of::<i32>(), std::mem::align_of::<i32>()),