From c605911cdf559ccea541de4c9b5de87caa2424d8 Mon Sep 17 00:00:00 2001
From: LongYinan <lynweklm@gmail.com>
Date: Mon, 11 Apr 2022 14:31:09 +0800
Subject: [PATCH] chore(napi): show tips if create different buffers with same
 data

---
 .../src/bindgen_runtime/js_values/buffer.rs   | 19 +++++++++++++++++++
 crates/napi/src/bindgen_runtime/mod.rs        |  7 +++++++
 2 files changed, 26 insertions(+)

diff --git a/crates/napi/src/bindgen_runtime/js_values/buffer.rs b/crates/napi/src/bindgen_runtime/js_values/buffer.rs
index 4c3fde3c..0565aaad 100644
--- a/crates/napi/src/bindgen_runtime/js_values/buffer.rs
+++ b/crates/napi/src/bindgen_runtime/js_values/buffer.rs
@@ -1,10 +1,19 @@
+#[cfg(debug_assertions)]
+use std::collections::HashSet;
 use std::mem;
 use std::ops::{Deref, DerefMut};
 use std::ptr;
 use std::slice;
+#[cfg(debug_assertions)]
+use std::sync::Mutex;
 
 use crate::{bindgen_prelude::*, check_status, sys, Result, ValueType};
 
+#[cfg(debug_assertions)]
+thread_local! {
+  pub (crate) static BUFFER_DATA: Mutex<HashSet<*mut u8>> = Default::default();
+}
+
 /// Zero copy u8 vector shared between rust and napi.
 /// Auto reference the raw JavaScript value, and release it when dropped.
 /// So it is safe to use it in `async fn`, the `&[u8]` under the hood will not be dropped until the `drop` called.
@@ -53,6 +62,16 @@ impl Buffer {
 impl From<Vec<u8>> for Buffer {
   fn from(mut data: Vec<u8>) -> Self {
     let inner_ptr = data.as_mut_ptr();
+    #[cfg(debug_assertions)]
+    {
+      let is_existed = BUFFER_DATA.with(|buffer_data| {
+        let buffer = buffer_data.lock().expect("Unlock buffer data failed");
+        buffer.contains(&inner_ptr)
+      });
+      if is_existed {
+        panic!("Share the same data between different buffers is not allowed, see: https://github.com/nodejs/node/issues/32463#issuecomment-631974747");
+      }
+    }
     let len = data.len();
     let capacity = data.capacity();
     mem::forget(data);
diff --git a/crates/napi/src/bindgen_runtime/mod.rs b/crates/napi/src/bindgen_runtime/mod.rs
index 7b116eb6..13b69bf7 100644
--- a/crates/napi/src/bindgen_runtime/mod.rs
+++ b/crates/napi/src/bindgen_runtime/mod.rs
@@ -52,6 +52,13 @@ pub unsafe extern "C" fn drop_buffer(
   finalize_hint: *mut c_void,
 ) {
   let length_ptr = finalize_hint as *mut (usize, usize);
+  #[cfg(debug_assertions)]
+  {
+    js_values::BUFFER_DATA.with(|buffer_data| {
+      let mut buffer = buffer_data.lock().expect("Unlock Buffer data failed");
+      buffer.remove(&(finalize_data as *mut u8));
+    });
+  }
   unsafe {
     let (length, cap) = *Box::from_raw(length_ptr);
     mem::drop(Vec::from_raw_parts(finalize_data as *mut u8, length, cap));