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// -*- C++ -*-
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//===--------------------------- mutex ------------------------------------===//
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//
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//                     The LLVM Compiler Infrastructure
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//
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// This file is dual licensed under the MIT and the University of Illinois Open
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// Source Licenses. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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#ifndef _LIBCPP_MUTEX
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#define _LIBCPP_MUTEX
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/*
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    mutex synopsis
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namespace std
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{
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class mutex
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{
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public:
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     constexpr mutex() noexcept;
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     ~mutex();
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    mutex(const mutex&) = delete;
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    mutex& operator=(const mutex&) = delete;
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    void lock();
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    bool try_lock();
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    void unlock();
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    typedef pthread_mutex_t* native_handle_type;
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    native_handle_type native_handle();
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};
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class recursive_mutex
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{
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public:
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     recursive_mutex();
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     ~recursive_mutex();
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    recursive_mutex(const recursive_mutex&) = delete;
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    recursive_mutex& operator=(const recursive_mutex&) = delete;
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    void lock();
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    bool try_lock() noexcept;
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    void unlock();
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    typedef pthread_mutex_t* native_handle_type;
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    native_handle_type native_handle();
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};
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class timed_mutex
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{
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public:
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     timed_mutex();
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     ~timed_mutex();
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    timed_mutex(const timed_mutex&) = delete;
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    timed_mutex& operator=(const timed_mutex&) = delete;
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    void lock();
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    bool try_lock();
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    template <class Rep, class Period>
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        bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
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    template <class Clock, class Duration>
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        bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
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    void unlock();
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};
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class recursive_timed_mutex
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{
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public:
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     recursive_timed_mutex();
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     ~recursive_timed_mutex();
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    recursive_timed_mutex(const recursive_timed_mutex&) = delete;
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    recursive_timed_mutex& operator=(const recursive_timed_mutex&) = delete;
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    void lock();
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    bool try_lock() noexcept;
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    template <class Rep, class Period>
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        bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
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    template <class Clock, class Duration>
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        bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
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    void unlock();
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};
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struct defer_lock_t {};
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struct try_to_lock_t {};
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struct adopt_lock_t {};
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constexpr defer_lock_t  defer_lock{};
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constexpr try_to_lock_t try_to_lock{};
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constexpr adopt_lock_t  adopt_lock{};
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template <class Mutex>
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class lock_guard
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{
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public:
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    typedef Mutex mutex_type;
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    explicit lock_guard(mutex_type& m);
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    lock_guard(mutex_type& m, adopt_lock_t);
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    ~lock_guard();
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    lock_guard(lock_guard const&) = delete;
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    lock_guard& operator=(lock_guard const&) = delete;
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};
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template <class Mutex>
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class unique_lock
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{
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public:
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    typedef Mutex mutex_type;
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    unique_lock() noexcept;
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    explicit unique_lock(mutex_type& m);
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    unique_lock(mutex_type& m, defer_lock_t) noexcept;
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    unique_lock(mutex_type& m, try_to_lock_t);
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    unique_lock(mutex_type& m, adopt_lock_t);
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    template <class Clock, class Duration>
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        unique_lock(mutex_type& m, const chrono::time_point<Clock, Duration>& abs_time);
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    template <class Rep, class Period>
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        unique_lock(mutex_type& m, const chrono::duration<Rep, Period>& rel_time);
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    ~unique_lock();
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    unique_lock(unique_lock const&) = delete;
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    unique_lock& operator=(unique_lock const&) = delete;
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    unique_lock(unique_lock&& u) noexcept;
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    unique_lock& operator=(unique_lock&& u) noexcept;
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    void lock();
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    bool try_lock();
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    template <class Rep, class Period>
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        bool try_lock_for(const chrono::duration<Rep, Period>& rel_time);
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    template <class Clock, class Duration>
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        bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time);
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    void unlock();
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    void swap(unique_lock& u) noexcept;
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    mutex_type* release() noexcept;
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    bool owns_lock() const noexcept;
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    explicit operator bool () const noexcept;
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    mutex_type* mutex() const noexcept;
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};
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template <class Mutex>
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  void swap(unique_lock<Mutex>& x, unique_lock<Mutex>& y) noexcept;
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template <class L1, class L2, class... L3>
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  int try_lock(L1&, L2&, L3&...);
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template <class L1, class L2, class... L3>
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  void lock(L1&, L2&, L3&...);
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struct once_flag
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{
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    constexpr once_flag() noexcept;
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    once_flag(const once_flag&) = delete;
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    once_flag& operator=(const once_flag&) = delete;
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};
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template<class Callable, class ...Args>
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  void call_once(once_flag& flag, Callable&& func, Args&&... args);
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}  // std
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*/
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#include <__config>
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#if !defined(_LIBCPP_HAS_NO_THREADS) && defined(__minix)
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#include <__mutex_base>
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#endif // !defined(_LIBCPP_HAS_NO_THREADS) && defined(__minix)
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#include <functional>
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#include <memory>
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#ifndef _LIBCPP_HAS_NO_VARIADICS
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#include <tuple>
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#endif
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#include <sched.h>
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#include <__undef_min_max>
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#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
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#pragma GCC system_header
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#endif
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_LIBCPP_BEGIN_NAMESPACE_STD
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#ifndef _LIBCPP_HAS_NO_THREADS
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class _LIBCPP_TYPE_VIS recursive_mutex
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{
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    pthread_mutex_t __m_;
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public:
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     recursive_mutex();
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     ~recursive_mutex();
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private:
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    recursive_mutex(const recursive_mutex&); // = delete;
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    recursive_mutex& operator=(const recursive_mutex&); // = delete;
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public:
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    void lock();
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    bool try_lock() _NOEXCEPT;
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    void unlock()  _NOEXCEPT;
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    typedef pthread_mutex_t* native_handle_type;
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    _LIBCPP_INLINE_VISIBILITY
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    native_handle_type native_handle() {return &__m_;}
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};
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class _LIBCPP_TYPE_VIS timed_mutex
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{
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    mutex              __m_;
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    condition_variable __cv_;
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    bool               __locked_;
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public:
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     timed_mutex();
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     ~timed_mutex();
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private:
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    timed_mutex(const timed_mutex&); // = delete;
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    timed_mutex& operator=(const timed_mutex&); // = delete;
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public:
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    void lock();
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    bool try_lock() _NOEXCEPT;
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    template <class _Rep, class _Period>
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        _LIBCPP_INLINE_VISIBILITY
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        bool try_lock_for(const chrono::duration<_Rep, _Period>& __d)
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            {return try_lock_until(chrono::steady_clock::now() + __d);}
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    template <class _Clock, class _Duration>
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        bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __t);
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    void unlock() _NOEXCEPT;
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};
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template <class _Clock, class _Duration>
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bool
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timed_mutex::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t)
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{
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    using namespace chrono;
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    unique_lock<mutex> __lk(__m_);
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    bool no_timeout = _Clock::now() < __t;
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    while (no_timeout && __locked_)
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        no_timeout = __cv_.wait_until(__lk, __t) == cv_status::no_timeout;
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    if (!__locked_)
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    {
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        __locked_ = true;
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        return true;
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    }
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    return false;
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}
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class _LIBCPP_TYPE_VIS recursive_timed_mutex
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{
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    mutex              __m_;
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    condition_variable __cv_;
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    size_t             __count_;
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    pthread_t          __id_;
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public:
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     recursive_timed_mutex();
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     ~recursive_timed_mutex();
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private:
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    recursive_timed_mutex(const recursive_timed_mutex&); // = delete;
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    recursive_timed_mutex& operator=(const recursive_timed_mutex&); // = delete;
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public:
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    void lock();
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    bool try_lock() _NOEXCEPT;
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    template <class _Rep, class _Period>
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        _LIBCPP_INLINE_VISIBILITY
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        bool try_lock_for(const chrono::duration<_Rep, _Period>& __d)
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            {return try_lock_until(chrono::steady_clock::now() + __d);}
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    template <class _Clock, class _Duration>
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        bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __t);
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    void unlock() _NOEXCEPT;
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};
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template <class _Clock, class _Duration>
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bool
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recursive_timed_mutex::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t)
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{
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    using namespace chrono;
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    pthread_t __id = pthread_self();
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    unique_lock<mutex> lk(__m_);
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    if (pthread_equal(__id, __id_))
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    {
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        if (__count_ == numeric_limits<size_t>::max())
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            return false;
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        ++__count_;
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        return true;
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    }
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    bool no_timeout = _Clock::now() < __t;
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    while (no_timeout && __count_ != 0)
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        no_timeout = __cv_.wait_until(lk, __t) == cv_status::no_timeout;
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    if (__count_ == 0)
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    {
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        __count_ = 1;
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        __id_ = __id;
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        return true;
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    }
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    return false;
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}
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template <class _L0, class _L1>
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int
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try_lock(_L0& __l0, _L1& __l1)
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{
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    unique_lock<_L0> __u0(__l0, try_to_lock);
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    if (__u0.owns_lock())
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    {
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        if (__l1.try_lock())
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        {
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            __u0.release();
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            return -1;
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        }
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        else
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            return 1;
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    }
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    return 0;
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}
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#ifndef _LIBCPP_HAS_NO_VARIADICS
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template <class _L0, class _L1, class _L2, class... _L3>
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int
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try_lock(_L0& __l0, _L1& __l1, _L2& __l2, _L3&... __l3)
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{
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    int __r = 0;
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    unique_lock<_L0> __u0(__l0, try_to_lock);
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    if (__u0.owns_lock())
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    {
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        __r = try_lock(__l1, __l2, __l3...);
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        if (__r == -1)
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            __u0.release();
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        else
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            ++__r;
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    }
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    return __r;
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}
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#endif  // _LIBCPP_HAS_NO_VARIADICS
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template <class _L0, class _L1>
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void
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lock(_L0& __l0, _L1& __l1)
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{
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    while (true)
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    {
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        {
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            unique_lock<_L0> __u0(__l0);
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            if (__l1.try_lock())
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            {
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                __u0.release();
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                break;
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            }
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        }
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        sched_yield();
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        {
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            unique_lock<_L1> __u1(__l1);
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            if (__l0.try_lock())
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            {
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                __u1.release();
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                break;
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            }
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        }
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        sched_yield();
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    }
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}
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#ifndef _LIBCPP_HAS_NO_VARIADICS
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template <class _L0, class _L1, class _L2, class ..._L3>
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void
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__lock_first(int __i, _L0& __l0, _L1& __l1, _L2& __l2, _L3& ...__l3)
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{
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    while (true)
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    {
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        switch (__i)
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        {
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        case 0:
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            {
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                unique_lock<_L0> __u0(__l0);
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                __i = try_lock(__l1, __l2, __l3...);
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                if (__i == -1)
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                {
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                    __u0.release();
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                    return;
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                }
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            }
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            ++__i;
399
            sched_yield();
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            break;
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        case 1:
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            {
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                unique_lock<_L1> __u1(__l1);
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                __i = try_lock(__l2, __l3..., __l0);
405
                if (__i == -1)
406
                {
407
                    __u1.release();
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                    return;
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                }
410
            }
411
            if (__i == sizeof...(_L3) + 1)
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                __i = 0;
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            else
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                __i += 2;
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            sched_yield();
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            break;
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        default:
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            __lock_first(__i - 2, __l2, __l3..., __l0, __l1);
419
            return;
420
        }
421
    }
422
}
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template <class _L0, class _L1, class _L2, class ..._L3>
425
inline _LIBCPP_INLINE_VISIBILITY
426
void
427
lock(_L0& __l0, _L1& __l1, _L2& __l2, _L3& ...__l3)
428
{
429
    __lock_first(0, __l0, __l1, __l2, __l3...);
430
}
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#endif  // _LIBCPP_HAS_NO_VARIADICS
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#endif // !_LIBCPP_HAS_NO_THREADS
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struct _LIBCPP_TYPE_VIS_ONLY once_flag;
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#ifndef _LIBCPP_HAS_NO_VARIADICS
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template<class _Callable, class... _Args>
441
_LIBCPP_INLINE_VISIBILITY
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void call_once(once_flag&, _Callable&&, _Args&&...);
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#else  // _LIBCPP_HAS_NO_VARIADICS
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template<class _Callable>
447
_LIBCPP_INLINE_VISIBILITY
448
void call_once(once_flag&, _Callable&);
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450
template<class _Callable>
451
_LIBCPP_INLINE_VISIBILITY
452
void call_once(once_flag&, const _Callable&);
453
454
#endif  // _LIBCPP_HAS_NO_VARIADICS
455
456
struct _LIBCPP_TYPE_VIS_ONLY once_flag
457
{
458
    _LIBCPP_INLINE_VISIBILITY
459
    _LIBCPP_CONSTEXPR
460
        once_flag() _NOEXCEPT : __state_(0) {}
461
462
private:
463
    once_flag(const once_flag&); // = delete;
464
    once_flag& operator=(const once_flag&); // = delete;
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466
    unsigned long __state_;
467
468
#ifndef _LIBCPP_HAS_NO_VARIADICS
469
    template<class _Callable, class... _Args>
470
    friend
471
    void call_once(once_flag&, _Callable&&, _Args&&...);
472
#else  // _LIBCPP_HAS_NO_VARIADICS
473
    template<class _Callable>
474
    friend
475
    void call_once(once_flag&, _Callable&);
476
477
    template<class _Callable>
478
    friend
479
    void call_once(once_flag&, const _Callable&);
480
#endif  // _LIBCPP_HAS_NO_VARIADICS
481
};
482
483
#ifndef _LIBCPP_HAS_NO_VARIADICS
484
485
template <class _Fp>
486
class __call_once_param
487
{
488
    _Fp& __f_;
489
public:
490
    _LIBCPP_INLINE_VISIBILITY
491
    explicit __call_once_param(_Fp& __f) : __f_(__f) {}
492
493
    _LIBCPP_INLINE_VISIBILITY
494
    void operator()()
495
    {
496
        typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 1>::type _Index;
497
        __execute(_Index());
498
    }
499
500
private:
501
    template <size_t ..._Indices>
502
    _LIBCPP_INLINE_VISIBILITY
503
    void __execute(__tuple_indices<_Indices...>)
504
    {
505
        __invoke(_VSTD::get<0>(_VSTD::move(__f_)), _VSTD::get<_Indices>(_VSTD::move(__f_))...);
506
    }
507
};
508
509
#else
510
511
template <class _Fp>
512
class __call_once_param
513
{
514
    _Fp& __f_;
515
public:
516
    _LIBCPP_INLINE_VISIBILITY
517
    explicit __call_once_param(_Fp& __f) : __f_(__f) {}
518
519
    _LIBCPP_INLINE_VISIBILITY
520
    void operator()()
521
    {
522
        __f_();
523
    }
524
};
525
526
#endif
527
528
template <class _Fp>
529
void
530
__call_once_proxy(void* __vp)
531
{
532
    __call_once_param<_Fp>* __p = static_cast<__call_once_param<_Fp>*>(__vp);
533
    (*__p)();
534
}
535
536
_LIBCPP_FUNC_VIS void __call_once(volatile unsigned long&, void*, void(*)(void*));
537
538
#ifndef _LIBCPP_HAS_NO_VARIADICS
539
540
template<class _Callable, class... _Args>
541
inline _LIBCPP_INLINE_VISIBILITY
542
void
543
call_once(once_flag& __flag, _Callable&& __func, _Args&&... __args)
544
{
545
    if (__libcpp_relaxed_load(&__flag.__state_) != ~0ul)
546
    {
547
        typedef tuple<_Callable&&, _Args&&...> _Gp;
548
        _Gp __f(_VSTD::forward<_Callable>(__func), _VSTD::forward<_Args>(__args)...);
549
        __call_once_param<_Gp> __p(__f);
550
        __call_once(__flag.__state_, &__p, &__call_once_proxy<_Gp>);
551
    }
552
}
553
554
#else  // _LIBCPP_HAS_NO_VARIADICS
555
556
template<class _Callable>
557
inline _LIBCPP_INLINE_VISIBILITY
558
void
559
call_once(once_flag& __flag, _Callable& __func)
560
{
561
    if (__libcpp_relaxed_load(&__flag.__state_) != ~0ul)
562
    {
563
        __call_once_param<_Callable> __p(__func);
564
        __call_once(__flag.__state_, &__p, &__call_once_proxy<_Callable>);
565
    }
566
}
567
568
template<class _Callable>
569
inline _LIBCPP_INLINE_VISIBILITY
570
void
571
call_once(once_flag& __flag, const _Callable& __func)
572
{
573
    if (__flag.__state_ != ~0ul)
574
    {
575
        __call_once_param<const _Callable> __p(__func);
576
        __call_once(__flag.__state_, &__p, &__call_once_proxy<const _Callable>);
577
    }
578
}
579
580
#endif  // _LIBCPP_HAS_NO_VARIADICS
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582
_LIBCPP_END_NAMESPACE_STD
583
584
#endif  // _LIBCPP_MUTEX