LCOM1920-T02G10

// -*- C++ -*-

//===--------------------------- thread -----------------------------------===//

//

//                     The LLVM Compiler Infrastructure

//

// This file is dual licensed under the MIT and the University of Illinois Open

// Source Licenses. See LICENSE.TXT for details.

//

//===----------------------------------------------------------------------===//

#ifndef _LIBCPP_THREAD

#define _LIBCPP_THREAD

/*

    thread synopsis

#define __STDCPP_THREADS__ __cplusplus

namespace std

{

class thread

{

public:

    class id;

    typedef pthread_t native_handle_type;

    thread() noexcept;

    template <class F, class ...Args> explicit thread(F&& f, Args&&... args);

    ~thread();

    thread(const thread&) = delete;

    thread(thread&& t) noexcept;

    thread& operator=(const thread&) = delete;

    thread& operator=(thread&& t) noexcept;

    void swap(thread& t) noexcept;

    bool joinable() const noexcept;

    void join();

    void detach();

    id get_id() const noexcept;

    native_handle_type native_handle();

    static unsigned hardware_concurrency() noexcept;

};

void swap(thread& x, thread& y) noexcept;

class thread::id

{

public:

    id() noexcept;

};

bool operator==(thread::id x, thread::id y) noexcept;

bool operator!=(thread::id x, thread::id y) noexcept;

bool operator< (thread::id x, thread::id y) noexcept;

bool operator<=(thread::id x, thread::id y) noexcept;

bool operator> (thread::id x, thread::id y) noexcept;

bool operator>=(thread::id x, thread::id y) noexcept;

template<class charT, class traits>

basic_ostream<charT, traits>&

operator<<(basic_ostream<charT, traits>& out, thread::id id);

namespace this_thread

{

thread::id get_id() noexcept;

void yield() noexcept;

template <class Clock, class Duration>

void sleep_until(const chrono::time_point<Clock, Duration>& abs_time);

template <class Rep, class Period>

void sleep_for(const chrono::duration<Rep, Period>& rel_time);

}  // this_thread

}  // std

*/

#include <__config>

#include <iosfwd>

#include <__functional_base>

#include <type_traits>

#include <cstddef>

#include <functional>

#include <memory>

#include <system_error>

#include <chrono>

#include <__mutex_base>

#ifndef _LIBCPP_HAS_NO_VARIADICS

#include <tuple>

#endif

#include <pthread.h>

#include <sched.h>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)

#pragma GCC system_header

#endif

#define __STDCPP_THREADS__ __cplusplus

#ifdef _LIBCPP_HAS_NO_THREADS

#error <thread> is not supported on this single threaded system

#else // !_LIBCPP_HAS_NO_THREADS

_LIBCPP_BEGIN_NAMESPACE_STD

template <class _Tp> class __thread_specific_ptr;

class _LIBCPP_TYPE_VIS __thread_struct;

class _LIBCPP_HIDDEN __thread_struct_imp;

class __assoc_sub_state;

_LIBCPP_FUNC_VIS __thread_specific_ptr<__thread_struct>& __thread_local_data();

class _LIBCPP_TYPE_VIS __thread_struct

{

    __thread_struct_imp* __p_;

    __thread_struct(const __thread_struct&);

    __thread_struct& operator=(const __thread_struct&);

public:

    __thread_struct();

    ~__thread_struct();

    void notify_all_at_thread_exit(condition_variable*, mutex*);

    void __make_ready_at_thread_exit(__assoc_sub_state*);

};

template <class _Tp>

class __thread_specific_ptr

{

    pthread_key_t __key_;

     // Only __thread_local_data() may construct a __thread_specific_ptr

     // and only with _Tp == __thread_struct.

    static_assert((is_same<_Tp, __thread_struct>::value), "");

    __thread_specific_ptr();

    friend _LIBCPP_FUNC_VIS __thread_specific_ptr<__thread_struct>& __thread_local_data();

    __thread_specific_ptr(const __thread_specific_ptr&);

    __thread_specific_ptr& operator=(const __thread_specific_ptr&);

    static void __at_thread_exit(void*);

public:

    typedef _Tp* pointer;

    ~__thread_specific_ptr();

    _LIBCPP_INLINE_VISIBILITY

    pointer get() const {return static_cast<_Tp*>(pthread_getspecific(__key_));}

    _LIBCPP_INLINE_VISIBILITY

    pointer operator*() const {return *get();}

    _LIBCPP_INLINE_VISIBILITY

    pointer operator->() const {return get();}

    pointer release();

    void reset(pointer __p = nullptr);

};

template <class _Tp>

void

__thread_specific_ptr<_Tp>::__at_thread_exit(void* __p)

{

    delete static_cast<pointer>(__p);

}

template <class _Tp>

__thread_specific_ptr<_Tp>::__thread_specific_ptr()

{

    int __ec = pthread_key_create(&__key_, &__thread_specific_ptr::__at_thread_exit);

#ifndef _LIBCPP_NO_EXCEPTIONS

    if (__ec)

        throw system_error(error_code(__ec, system_category()),

                           "__thread_specific_ptr construction failed");

#endif

}

template <class _Tp>

__thread_specific_ptr<_Tp>::~__thread_specific_ptr()

{

    // __thread_specific_ptr is only created with a static storage duration

    // so this destructor is only invoked during program termination. Invoking

    // pthread_key_delete(__key_) may prevent other threads from deleting their

    // thread local data. For this reason we leak the key.

}

template <class _Tp>

typename __thread_specific_ptr<_Tp>::pointer

__thread_specific_ptr<_Tp>::release()

{

    pointer __p = get();

    pthread_setspecific(__key_, 0);

    return __p;

}

template <class _Tp>

void

__thread_specific_ptr<_Tp>::reset(pointer __p)

{

    pointer __p_old = get();

    pthread_setspecific(__key_, __p);

    delete __p_old;

}

class _LIBCPP_TYPE_VIS thread;

class _LIBCPP_TYPE_VIS __thread_id;

namespace this_thread

{

_LIBCPP_INLINE_VISIBILITY __thread_id get_id() _NOEXCEPT;

}  // this_thread

template<> struct _LIBCPP_TYPE_VIS_ONLY hash<__thread_id>;

class _LIBCPP_TYPE_VIS_ONLY __thread_id

{

    // FIXME: pthread_t is a pointer on Darwin but a long on Linux.

    // NULL is the no-thread value on Darwin.  Someone needs to check

    // on other platforms.  We assume 0 works everywhere for now.

    pthread_t __id_;

public:

    _LIBCPP_INLINE_VISIBILITY

    __thread_id() _NOEXCEPT : __id_(0) {}

    friend _LIBCPP_INLINE_VISIBILITY

        bool operator==(__thread_id __x, __thread_id __y) _NOEXCEPT

        {return __x.__id_ == __y.__id_;}

    friend _LIBCPP_INLINE_VISIBILITY

        bool operator!=(__thread_id __x, __thread_id __y) _NOEXCEPT

        {return !(__x == __y);}

    friend _LIBCPP_INLINE_VISIBILITY

        bool operator< (__thread_id __x, __thread_id __y) _NOEXCEPT

        {return __x.__id_ < __y.__id_;}

    friend _LIBCPP_INLINE_VISIBILITY

        bool operator<=(__thread_id __x, __thread_id __y) _NOEXCEPT

        {return !(__y < __x);}

    friend _LIBCPP_INLINE_VISIBILITY

        bool operator> (__thread_id __x, __thread_id __y) _NOEXCEPT

        {return   __y < __x ;}

    friend _LIBCPP_INLINE_VISIBILITY

        bool operator>=(__thread_id __x, __thread_id __y) _NOEXCEPT

        {return !(__x < __y);}

    template<class _CharT, class _Traits>

    friend

    _LIBCPP_INLINE_VISIBILITY

    basic_ostream<_CharT, _Traits>&

    operator<<(basic_ostream<_CharT, _Traits>& __os, __thread_id __id)

        {return __os << __id.__id_;}

private:

    _LIBCPP_INLINE_VISIBILITY

    __thread_id(pthread_t __id) : __id_(__id) {}

    friend __thread_id this_thread::get_id() _NOEXCEPT;

    friend class _LIBCPP_TYPE_VIS thread;

    friend struct _LIBCPP_TYPE_VIS_ONLY hash<__thread_id>;

};

template<>

struct _LIBCPP_TYPE_VIS_ONLY hash<__thread_id>

    : public unary_function<__thread_id, size_t>

{

    _LIBCPP_INLINE_VISIBILITY

    size_t operator()(__thread_id __v) const

    {

        return hash<pthread_t>()(__v.__id_);

    }

};

namespace this_thread

{

inline _LIBCPP_INLINE_VISIBILITY

__thread_id

get_id() _NOEXCEPT

{

    return pthread_self();

}

}  // this_thread

class _LIBCPP_TYPE_VIS thread

{

    pthread_t __t_;

    thread(const thread&);

    thread& operator=(const thread&);

public:

    typedef __thread_id id;

    typedef pthread_t native_handle_type;

    _LIBCPP_INLINE_VISIBILITY

    thread() _NOEXCEPT : __t_(0) {}

#ifndef _LIBCPP_HAS_NO_VARIADICS

    template <class _Fp, class ..._Args,

              class = typename enable_if

              <

                   !is_same<typename decay<_Fp>::type, thread>::value

              >::type

             >

        explicit thread(_Fp&& __f, _Args&&... __args);

#else  // _LIBCPP_HAS_NO_VARIADICS

    template <class _Fp> explicit thread(_Fp __f);

#endif

    ~thread();

#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES

    _LIBCPP_INLINE_VISIBILITY

    thread(thread&& __t) _NOEXCEPT : __t_(__t.__t_) {__t.__t_ = 0;}

    thread& operator=(thread&& __t) _NOEXCEPT;

#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES

    _LIBCPP_INLINE_VISIBILITY

    void swap(thread& __t) _NOEXCEPT {_VSTD::swap(__t_, __t.__t_);}

    _LIBCPP_INLINE_VISIBILITY

    bool joinable() const _NOEXCEPT {return __t_ != 0;}

    void join();

    void detach();

    _LIBCPP_INLINE_VISIBILITY

    id get_id() const _NOEXCEPT {return __t_;}

    _LIBCPP_INLINE_VISIBILITY

    native_handle_type native_handle() _NOEXCEPT {return __t_;}

    static unsigned hardware_concurrency() _NOEXCEPT;

};

#ifndef _LIBCPP_HAS_NO_VARIADICS

template <class _Fp, class ..._Args, size_t ..._Indices>

inline _LIBCPP_INLINE_VISIBILITY

void

__thread_execute(tuple<_Fp, _Args...>& __t, __tuple_indices<_Indices...>)

{

    __invoke(_VSTD::move(_VSTD::get<0>(__t)), _VSTD::move(_VSTD::get<_Indices>(__t))...);

}

template <class _Fp>

void*

__thread_proxy(void* __vp)

{

    __thread_local_data().reset(new __thread_struct);

    std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));

    typedef typename __make_tuple_indices<tuple_size<_Fp>::value, 1>::type _Index;

    __thread_execute(*__p, _Index());

    return nullptr;

}

template <class _Fp, class ..._Args,

          class

         >

thread::thread(_Fp&& __f, _Args&&... __args)

{

    typedef tuple<typename decay<_Fp>::type, typename decay<_Args>::type...> _Gp;

    _VSTD::unique_ptr<_Gp> __p(new _Gp(__decay_copy(_VSTD::forward<_Fp>(__f)),

                                __decay_copy(_VSTD::forward<_Args>(__args))...));

    int __ec = pthread_create(&__t_, 0, &__thread_proxy<_Gp>, __p.get());

    if (__ec == 0)

        __p.release();

    else

        __throw_system_error(__ec, "thread constructor failed");

}

#else  // _LIBCPP_HAS_NO_VARIADICS

template <class _Fp>

void*

__thread_proxy(void* __vp)

{

    __thread_local_data().reset(new __thread_struct);

    std::unique_ptr<_Fp> __p(static_cast<_Fp*>(__vp));

    (*__p)();

    return nullptr;

}

template <class _Fp>

thread::thread(_Fp __f)

{

    std::unique_ptr<_Fp> __p(new _Fp(__f));

    int __ec = pthread_create(&__t_, 0, &__thread_proxy<_Fp>, __p.get());

    if (__ec == 0)

        __p.release();

    else

        __throw_system_error(__ec, "thread constructor failed");

}

#endif  // _LIBCPP_HAS_NO_VARIADICS

#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES

inline _LIBCPP_INLINE_VISIBILITY

thread&

thread::operator=(thread&& __t) _NOEXCEPT

{

    if (__t_ != 0)

        terminate();

    __t_ = __t.__t_;

    __t.__t_ = 0;

    return *this;

}

#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES

inline _LIBCPP_INLINE_VISIBILITY

void swap(thread& __x, thread& __y) _NOEXCEPT {__x.swap(__y);}

namespace this_thread

{

_LIBCPP_FUNC_VIS void sleep_for(const chrono::nanoseconds& ns);

template <class _Rep, class _Period>

void

sleep_for(const chrono::duration<_Rep, _Period>& __d)

{

    using namespace chrono;

    if (__d > duration<_Rep, _Period>::zero())

    {

        _LIBCPP_CONSTEXPR duration<long double> _Max = nanoseconds::max();

        nanoseconds __ns;

        if (__d < _Max)

        {

            __ns = duration_cast<nanoseconds>(__d);

            if (__ns < __d)

                ++__ns;

        }

        else

            __ns = nanoseconds::max();

        sleep_for(__ns);

    }

}

template <class _Clock, class _Duration>

void

sleep_until(const chrono::time_point<_Clock, _Duration>& __t)

{

    using namespace chrono;

    mutex __mut;

    condition_variable __cv;

    unique_lock<mutex> __lk(__mut);

    while (_Clock::now() < __t)

        __cv.wait_until(__lk, __t);

}

template <class _Duration>

inline _LIBCPP_INLINE_VISIBILITY

void

sleep_until(const chrono::time_point<chrono::steady_clock, _Duration>& __t)

{

    using namespace chrono;

    sleep_for(__t - steady_clock::now());

}

inline _LIBCPP_INLINE_VISIBILITY

void yield() _NOEXCEPT {sched_yield();}

}  // this_thread

_LIBCPP_END_NAMESPACE_STD

#endif // !_LIBCPP_HAS_NO_THREADS

#endif  // _LIBCPP_THREAD