[NFC][lldb] Introduce LockGuarded type

LockGuarded is a generic wrapper around a resource to ensure exclusive
access.

Author: augusto2112

lldb/source/Plugins/LanguageRuntime/Swift/LockGuarded.h

@@ -0,0 +1,39 @@
+//===----------------- LockGuarded.h ----------------------------*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2024 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef liblldb_SwiftLockGuarded_h_
+#define liblldb_SwiftLockGuarded_h_
+
+#include <mutex>
+
+namespace lldb_private {
+/// A generic wrapper around a resource which holds a lock to ensure
+/// exclusive access.
+template <typename Resource> struct LockGuarded {
+  LockGuarded(Resource *resource, std::recursive_mutex &mutex)
+      : m_resource(resource), m_lock(mutex, std::adopt_lock) {}
+
+  LockGuarded() = default;
+
+  Resource *operator->() const { return m_resource; }
+
+  Resource *operator*() const { return m_resource; }
+
+  operator bool() const { return m_resource != nullptr; }
+
+private:
+  Resource *m_resource;
+  std::unique_lock<std::recursive_mutex> m_lock;
+};
+
+} // namespace lldb_private
+#endif