///////////////////////////////////////////////////////////////////////////////

// Copyright (c) Lewis Baker

// Licenced under MIT license. See LICENSE.txt for details.

///////////////////////////////////////////////////////////////////////////////

#ifndef CPPCORO_SPIN_MUTEX_HPP_INCLUDED

#define CPPCORO_SPIN_MUTEX_HPP_INCLUDED

#include <atomic>

namespace cppcoro

{

class spin_mutex

{

public:

/// Initialise the mutex to the unlocked state.

spin_mutex() noexcept;

/// Attempt to lock the mutex without blocking

///

/// \return

/// true if the lock was acquired, false if the lock was already held

/// and could not be immediately acquired.

bool try_lock() noexcept;

/// Block the current thread until the lock is acquired.

///

/// This will busy-wait until it acquires the lock.

///

/// This has 'acquire' memory semantics and synchronises

/// with prior calls to unlock().

void lock() noexcept;

/// Release the lock.

///

/// This has 'release' memory semantics and synchronises with

/// lock() and try_lock().

void unlock() noexcept;

private:

std::atomic<bool> m_isLocked;

};

}

#endif