From 16b2bc18336ab3495c65b5feaef35461d540cfd5 Mon Sep 17 00:00:00 2001
From: Marcel Laverdet <marcel@laverdet.com>
Date: Tue, 3 May 2022 10:25:45 -0500
Subject: [PATCH] Fix deadlock from disposal under certain circumstances

Fixes #302
---
 src/isolate/scheduler.cc    | 14 +++++++-------
 src/isolate/scheduler.h     | 12 ++++++++++--
 tests/self-async-dispose.js |  9 +++++++++
 3 files changed, 26 insertions(+), 9 deletions(-)
 create mode 100644 tests/self-async-dispose.js

diff --git a/src/isolate/scheduler.cc b/src/isolate/scheduler.cc
index 51406a4..aebea70 100644
--- a/src/isolate/scheduler.cc
+++ b/src/isolate/scheduler.cc
@@ -171,24 +171,24 @@ Scheduler::AsyncWait::~AsyncWait() {
 }
 
 void Scheduler::AsyncWait::Ready() {
-	auto lock = scheduler.Lock();
-	ready = true;
-	if (done) {
+	auto lock = state.write();
+	lock->ready = true;
+	if (lock->done) {
 		scheduler.cv.notify_one();
 	}
 }
 
 void Scheduler::AsyncWait::Wait() {
 	std::unique_lock<std::mutex> lock{scheduler.mutex};
-	while (!ready || !done) {
+	while (!state.read()->did_initialize()) {
 		scheduler.cv.wait(lock);
 	}
 }
 
 void Scheduler::AsyncWait::Wake() {
-	auto lock = scheduler.Lock();
-	done = true;
-	if (ready) {
+	auto lock = state.write();
+	lock->done = true;
+	if (lock->ready) {
 		scheduler.cv.notify_one();
 	}
 }
diff --git a/src/isolate/scheduler.h b/src/isolate/scheduler.h
index 9ed2748..d9a76fb 100644
--- a/src/isolate/scheduler.h
+++ b/src/isolate/scheduler.h
@@ -68,9 +68,17 @@ class Scheduler {
 				void Wake();
 
 			private:
+				struct state_t {
+					bool ready = false;
+					bool done = false;
+
+					bool did_initialize() const {
+						return ready || done;
+					}
+				};
+
 				class LockedScheduler& scheduler;
-				bool done = false;
-				bool ready = false;
+				lockable_t<state_t> state;
 		};
 
 		// Task queues
diff --git a/tests/self-async-dispose.js b/tests/self-async-dispose.js
new file mode 100644
index 0000000..587d150
--- /dev/null
+++ b/tests/self-async-dispose.js
@@ -0,0 +1,9 @@
+const ivm = require('isolated-vm');
+
+const isolate = new ivm.Isolate();
+const context = isolate.createContextSync();
+context.global.setSync("getProm", () => {}, { reference: true });
+context.eval("getProm.applySync()").catch(() => console.log('pass'));
+context.release();
+process.nextTick(() => {});
+isolate.dispose();