From 636be07435cedd42e5607ed99ddb0d18bf4d26aa Mon Sep 17 00:00:00 2001
From: altalk23 <45172705+altalk23@users.noreply.github.com>
Date: Thu, 20 Jun 2024 16:17:02 +0300
Subject: [PATCH] fix event pool race condition in a hacky way
---
loader/include/Geode/loader/Dispatch.hpp | 4 +-
loader/include/Geode/loader/Event.hpp | 31 +++++++++++--
loader/src/loader/Event.cpp | 57 ++++++++++++++++--------
3 files changed, 69 insertions(+), 23 deletions(-)
diff --git a/loader/include/Geode/loader/Dispatch.hpp b/loader/include/Geode/loader/Dispatch.hpp
index ee66264e..1ce7bb9c 100644
--- a/loader/include/Geode/loader/Dispatch.hpp
+++ b/loader/include/Geode/loader/Dispatch.hpp
@@ -31,7 +31,7 @@ namespace geode {
EventListenerPool* getPool() const override {
if (dispatchPools().count(m_id) == 0) {
- dispatchPools()[m_id] = new DefaultEventListenerPool();
+ dispatchPools()[m_id] = DefaultEventListenerPool::create();
}
return dispatchPools()[m_id];
}
@@ -48,7 +48,7 @@ namespace geode {
EventListenerPool* getPool() const {
if (dispatchPools().count(m_id) == 0) {
- dispatchPools()[m_id] = new DefaultEventListenerPool();
+ dispatchPools()[m_id] = DefaultEventListenerPool::create();
}
return dispatchPools()[m_id];
}
diff --git a/loader/include/Geode/loader/Event.hpp b/loader/include/Geode/loader/Event.hpp
index 8b321bb3..c10f9a0a 100644
--- a/loader/include/Geode/loader/Event.hpp
+++ b/loader/include/Geode/loader/Event.hpp
@@ -5,6 +5,8 @@
#include <Geode/DefaultInclude.hpp>
#include <type_traits>
+#include <mutex>
+#include <deque>
#include <unordered_set>
namespace geode {
@@ -29,12 +31,29 @@ namespace geode {
EventListenerPool(EventListenerPool const&) = delete;
EventListenerPool(EventListenerPool&&) = delete;
};
+
+ template <class... Args>
+ class DispatchEvent;
+
+ template <class... Args>
+ class DispatchFilter;
class GEODE_DLL DefaultEventListenerPool : public EventListenerPool {
protected:
- std::atomic_size_t m_locked = 0;
- std::vector<EventListenerProtocol*> m_listeners;
- std::vector<EventListenerProtocol*> m_toAdd;
+ // fix this in Geode 4.0.0
+ struct Data {
+ std::atomic_size_t m_locked = 0;
+ std::mutex m_mutex;
+ std::deque<EventListenerProtocol*> m_listeners;
+ std::vector<EventListenerProtocol*> m_toAdd;
+ std::vector<EventListenerProtocol*> m_toRemove;
+ };
+ std::unique_ptr<Data> m_data;
+
+ DefaultEventListenerPool();
+
+ private:
+ static DefaultEventListenerPool* create();
public:
bool add(EventListenerProtocol* listener) override;
@@ -42,6 +61,12 @@ namespace geode {
ListenerResult handle(Event* event) override;
static DefaultEventListenerPool* get();
+
+ template <class... Args>
+ friend class DispatchEvent;
+
+ template <class... Args>
+ friend class DispatchFilter;
};
class GEODE_DLL EventListenerProtocol {
diff --git a/loader/src/loader/Event.cpp b/loader/src/loader/Event.cpp
index 1e6a8946..f2e42c8e 100644
--- a/loader/src/loader/Event.cpp
+++ b/loader/src/loader/Event.cpp
@@ -4,50 +4,71 @@
using namespace geode::prelude;
+DefaultEventListenerPool::DefaultEventListenerPool() : m_data(new Data) {}
+
bool DefaultEventListenerPool::add(EventListenerProtocol* listener) {
- if (m_locked) {
- m_toAdd.push_back(listener);
+ if (!m_data) m_data = std::make_unique<Data>();
+
+ std::unique_lock lock(m_data->m_mutex);
+ if (m_data->m_locked) {
+ m_data->m_toAdd.push_back(listener);
+ ranges::remove(m_data->m_toRemove, listener);
}
else {
// insert listeners at the start so new listeners get priority
- m_listeners.insert(m_listeners.begin(), listener);
+ m_data->m_listeners.push_front(listener);
}
return true;
}
void DefaultEventListenerPool::remove(EventListenerProtocol* listener) {
- for (size_t i = 0; i < m_listeners.size(); i++) {
- if (m_listeners[i] == listener) {
- m_listeners[i] = nullptr;
- }
+ if (!m_data) m_data = std::make_unique<Data>();
+
+ std::unique_lock lock(m_data->m_mutex);
+ if (m_data->m_locked) {
+ m_data->m_toRemove.push_back(listener);
+ ranges::remove(m_data->m_toAdd, listener);
+ }
+ else {
+ ranges::remove(m_data->m_listeners, listener);
}
- ranges::remove(m_toAdd, listener);
}
ListenerResult DefaultEventListenerPool::handle(Event* event) {
+ if (!m_data) m_data = std::make_unique<Data>();
+
auto res = ListenerResult::Propagate;
- m_locked += 1;
- for (auto h : m_listeners) {
- // if an event listener gets destroyed in the middle of this loop, it
- // gets set to null
+ m_data->m_locked += 1;
+ std::unique_lock lock(m_data->m_mutex);
+ for (auto h : m_data->m_listeners) {
+ lock.unlock();
if (h && h->handle(event) == ListenerResult::Stop) {
res = ListenerResult::Stop;
+ lock.lock();
break;
}
+ lock.lock();
}
- m_locked -= 1;
+ m_data->m_locked -= 1;
// only mutate listeners once nothing is iterating
// (if there are recursive handle calls)
- if (m_locked == 0) {
- ranges::remove(m_listeners, nullptr);
- for (auto listener : m_toAdd) {
- m_listeners.insert(m_listeners.begin(), listener);
+ if (m_data->m_locked == 0) {
+ for (auto listener : m_data->m_toRemove) {
+ ranges::remove(m_data->m_listeners, listener);
}
- m_toAdd.clear();
+ for (auto listener : m_data->m_toAdd) {
+ m_data->m_listeners.push_front(listener);
+ }
+ m_data->m_toAdd.clear();
+ m_data->m_toRemove.clear();
}
return res;
}
+DefaultEventListenerPool* DefaultEventListenerPool::create() {
+ return new DefaultEventListenerPool();
+}
+
DefaultEventListenerPool* DefaultEventListenerPool::get() {
static auto inst = new DefaultEventListenerPool();
return inst;