compat/spinlock: implement and use it

1 files changed, 30 insertions, 0 deletions

diff --git a/compat/spinlock.hpp b/compat/spinlock.hpp
new file mode 100644
index 00000000..7e4cd8cf
--- /dev/null
+++ b/compat/spinlock.hpp
@@ -0,0 +1,30 @@
+#pragma once
+
+#include "macros1.h"
+#include <atomic>
+
+struct spinlock_guard final
+{
+    spinlock_guard(const spinlock_guard&) = delete;
+    spinlock_guard& operator=(const spinlock_guard&) = delete;
+    constexpr spinlock_guard(spinlock_guard&&) noexcept = default;
+
+    cc_forceinline
+    spinlock_guard(std::atomic_flag* lock) noexcept : spinlock_guard(*lock) {}
+
+    cc_forceinline
+    spinlock_guard(std::atomic_flag& lock) noexcept : lock(lock)
+    {
+        while (lock.test_and_set(std::memory_order_acquire))
+            (void)0;
+    }
+
+    cc_forceinline
+    ~spinlock_guard() noexcept
+    {
+        lock.clear(std::memory_order_release);
+    }
+
+private:
+    std::atomic_flag& lock;
+};