From e590cc7150186235af929df23680097f77af2ca2 Mon Sep 17 00:00:00 2001
From: Borys <borys.patochkin@gmail.com>
Date: Sat, 19 Oct 2024 22:48:10 +0300
Subject: [PATCH] feat: allow reusing CondVar object during
 CondVar::notify_all()

---
 util/fibers/synchronization.h | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/util/fibers/synchronization.h b/util/fibers/synchronization.h
index e5c05f5a..6affd0a7 100644
--- a/util/fibers/synchronization.h
+++ b/util/fibers/synchronization.h
@@ -161,8 +161,14 @@ class CondVarAny {
   }
 
   void notify_all() noexcept {
-    if (!wait_queue_.empty())
-      wait_queue_.NotifyAll(detail::FiberActive());
+    if (!wait_queue_.empty()) {
+      detail::WaitQueue tmp_queue;
+      // this allows reusing CondVarAny object during WaitQueue::NotifyAll() execution
+      // if another thread decided to wait again on this object
+      std::swap(tmp_queue, wait_queue_);
+      tmp_queue.NotifyAll(detail::FiberActive());
+    }
+     
   }
 
   template <typename LockType> void wait(LockType& lt);