New shared_mutex

Experimental sync utils
New semaphore<>
New cond_variable
New owned_mutex

Utilities/cond.h

@@ -0,0 +1,50 @@
+#pragma once
+
+#include "types.h"
+#include "Atomic.h"
+
+// Lightweight condition variable
+class cond_variable
+{
+	// Internal waiter counter
+	atomic_t<u32> m_value{0};
+
+protected:
+	// Internal waiting function
+	bool imp_wait(u32 _old, u64 _timeout) noexcept;
+
+	// Try to notify up to _count threads
+	void imp_wake(u32 _count) noexcept;
+
+public:
+	constexpr cond_variable() = default;
+
+	// Intrusive wait algorithm for lockable objects
+	template <typename T, void (T::*Unlock)() = &T::unlock, void (T::*Lock)() = &T::lock>
+	explicit_bool_t wait(T& object, u64 usec_timeout = -1)
+	{
+		const u32 _old = m_value.fetch_add(1); // Increment waiter counter
+		(object.*Unlock)();
+		const bool res = imp_wait(_old, usec_timeout);
+		(object.*Lock)();
+		return res;
+	}
+
+	// Wake one thread
+	void notify_one() noexcept
+	{
+		if (m_value)
+		{
+			imp_wake(1);
+		}
+	}
+
+	// Wake all threads
+	void notify_all() noexcept
+	{
+		if (m_value)
+		{
+			imp_wake(-1);
+		}
+	}
+};