From cddf2994081f0ee6c3b9aad6bdd019d71a4ec5b5 Mon Sep 17 00:00:00 2001
From: Vladimir Byko-Ianko <v.bykoianko@corp.mail.ru>
Date: Thu, 29 Oct 2020 13:27:58 +0300
Subject: [PATCH] [base] Optional lock guard.

---
 base/CMakeLists.txt          |  1 +
 base/optional_lock_guard.hpp | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+)
 create mode 100644 base/optional_lock_guard.hpp

diff --git a/base/CMakeLists.txt b/base/CMakeLists.txt
index cd78655469..a6ac8de491 100644
--- a/base/CMakeLists.txt
+++ b/base/CMakeLists.txt
@@ -52,6 +52,7 @@ set(
   normalize_unicode.cpp
   non_intersecting_intervals.hpp
   observer_list.hpp
+  optional_lock_guard.hpp
   pprof.cpp
   pprof.hpp
   random.cpp
diff --git a/base/optional_lock_guard.hpp b/base/optional_lock_guard.hpp
new file mode 100644
index 0000000000..ac7254eba4
--- /dev/null
+++ b/base/optional_lock_guard.hpp
@@ -0,0 +1,21 @@
+#pragma once
+
+#include <mutex>
+#include <optional>
+
+namespace base
+{
+template <typename Mutex>
+class OptionalLockGuard
+{
+public:
+  explicit OptionalLockGuard(std::optional<Mutex> & optionalMutex)
+    : m_optionalGuard(optionalMutex ? std::optional<std::lock_guard<Mutex>>(*optionalMutex)
+                                    : std::nullopt)
+  {
+  }
+
+private:
+  std::optional<std::lock_guard<Mutex>> m_optionalGuard;
+};
+}