include/__mutex_base

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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___MUTEX_BASE
#define _LIBCPP___MUTEX_BASE

#include <__config>
#include <chrono>
#include <system_error>
#include <__threading_support>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif

_LIBCPP_BEGIN_NAMESPACE_STD

#ifndef _LIBCPP_HAS_NO_THREADS

#ifndef _LIBCPP_THREAD_SAFETY_ANNOTATION
# ifdef _LIBCPP_HAS_THREAD_SAFETY_ANNOTATIONS
# define _LIBCPP_THREAD_SAFETY_ANNOTATION(x) __attribute__((x))
# else
# define _LIBCPP_THREAD_SAFETY_ANNOTATION(x)
# endif
#endif // _LIBCPP_THREAD_SAFETY_ANNOTATION

class _LIBCPP_TYPE_VIS _LIBCPP_THREAD_SAFETY_ANNOTATION(capability("mutex")) mutex
{
#ifndef _LIBCPP_HAS_NO_CONSTEXPR
 __libcpp_mutex_t __m_ = _LIBCPP_MUTEX_INITIALIZER;
#else
 __libcpp_mutex_t __m_;
#endif

public:
 _LIBCPP_INLINE_VISIBILITY
#ifndef _LIBCPP_HAS_NO_CONSTEXPR
 constexpr mutex() _NOEXCEPT _LIBCPP_DEFAULT
#else
 mutex() _NOEXCEPT {__m_ = (__libcpp_mutex_t)_LIBCPP_MUTEX_INITIALIZER;}
#endif
 ~mutex();

private:
 mutex(const mutex&);// = delete;
 mutex& operator=(const mutex&);// = delete;

public:
 void lock() _LIBCPP_THREAD_SAFETY_ANNOTATION(acquire_capability());
 bool try_lock() _NOEXCEPT _LIBCPP_THREAD_SAFETY_ANNOTATION(try_acquire_capability(true));
 void unlock() _NOEXCEPT _LIBCPP_THREAD_SAFETY_ANNOTATION(release_capability());

 typedef __libcpp_mutex_t* native_handle_type;
 _LIBCPP_INLINE_VISIBILITY native_handle_type native_handle() {return &__m_;}
};

struct _LIBCPP_TYPE_VIS defer_lock_t {};
struct _LIBCPP_TYPE_VIS try_to_lock_t {};
struct _LIBCPP_TYPE_VIS adopt_lock_t {};

#if defined(_LIBCPP_HAS_NO_CONSTEXPR) || defined(_LIBCPP_BUILDING_MUTEX)

extern const defer_lock_t defer_lock;
extern const try_to_lock_t try_to_lock;
extern const adopt_lock_t adopt_lock;

#else

constexpr defer_lock_t defer_lock = defer_lock_t();
constexpr try_to_lock_t try_to_lock = try_to_lock_t();
constexpr adopt_lock_t adopt_lock = adopt_lock_t();

#endif


// Forward declare lock_guard as a variadic template even in C++03 to keep
// the mangling consistent between dialects.
#if defined(_LIBCPP_ABI_VARIADIC_LOCK_GUARD)
template <class ..._Mutexes>
class _LIBCPP_TYPE_VIS_ONLY lock_guard;
#endif

template <class _Mutex>
class _LIBCPP_TYPE_VIS_ONLY _LIBCPP_THREAD_SAFETY_ANNOTATION(scoped_lockable)
#if !defined(_LIBCPP_ABI_VARIADIC_LOCK_GUARD)
lock_guard
#else
lock_guard<_Mutex>
#endif
{
public:
 typedef _Mutex mutex_type;

private:
 mutex_type& __m_;
public:

 _LIBCPP_INLINE_VISIBILITY
 explicit lock_guard(mutex_type& __m) _LIBCPP_THREAD_SAFETY_ANNOTATION(acquire_capability(__m))
 : __m_(__m) {__m_.lock();}
 _LIBCPP_INLINE_VISIBILITY
 lock_guard(mutex_type& __m, adopt_lock_t) _LIBCPP_THREAD_SAFETY_ANNOTATION(requires_capability(__m))
 : __m_(__m) {}
 _LIBCPP_INLINE_VISIBILITY
 ~lock_guard() _LIBCPP_THREAD_SAFETY_ANNOTATION(release_capability()) {__m_.unlock();}

private:
 lock_guard(lock_guard const&) _LIBCPP_EQUAL_DELETE;
 lock_guard& operator=(lock_guard const&) _LIBCPP_EQUAL_DELETE;
};

template <class _Mutex>
class _LIBCPP_TYPE_VIS_ONLY unique_lock
{
public:
 typedef _Mutex mutex_type;

private:
 mutex_type* __m_;
 bool __owns_;

public:
 _LIBCPP_INLINE_VISIBILITY
 unique_lock() _NOEXCEPT : __m_(nullptr), __owns_(false) {}
 _LIBCPP_INLINE_VISIBILITY
 explicit unique_lock(mutex_type& __m)
 : __m_(_VSTD::addressof(__m)), __owns_(true) {__m_->lock();}
 _LIBCPP_INLINE_VISIBILITY
 unique_lock(mutex_type& __m, defer_lock_t) _NOEXCEPT
 : __m_(_VSTD::addressof(__m)), __owns_(false) {}
 _LIBCPP_INLINE_VISIBILITY
 unique_lock(mutex_type& __m, try_to_lock_t)
 : __m_(_VSTD::addressof(__m)), __owns_(__m.try_lock()) {}
 _LIBCPP_INLINE_VISIBILITY
 unique_lock(mutex_type& __m, adopt_lock_t)
 : __m_(_VSTD::addressof(__m)), __owns_(true) {}
 template <class _Clock, class _Duration>
 _LIBCPP_INLINE_VISIBILITY
 unique_lock(mutex_type& __m, const chrono::time_point<_Clock, _Duration>& __t)
 : __m_(_VSTD::addressof(__m)), __owns_(__m.try_lock_until(__t)) {}
 template <class _Rep, class _Period>
 _LIBCPP_INLINE_VISIBILITY
 unique_lock(mutex_type& __m, const chrono::duration<_Rep, _Period>& __d)
 : __m_(_VSTD::addressof(__m)), __owns_(__m.try_lock_for(__d)) {}
 _LIBCPP_INLINE_VISIBILITY
 ~unique_lock()
 {
 if (__owns_)
 __m_->unlock();
 }

private:
 unique_lock(unique_lock const&); // = delete;
 unique_lock& operator=(unique_lock const&); // = delete;

public:
#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
 _LIBCPP_INLINE_VISIBILITY
 unique_lock(unique_lock&& __u) _NOEXCEPT
 : __m_(__u.__m_), __owns_(__u.__owns_)
 {__u.__m_ = nullptr; __u.__owns_ = false;}
 _LIBCPP_INLINE_VISIBILITY
 unique_lock& operator=(unique_lock&& __u) _NOEXCEPT
 {
 if (__owns_)
 __m_->unlock();
 __m_ = __u.__m_;
 __owns_ = __u.__owns_;
 __u.__m_ = nullptr;
 __u.__owns_ = false;
 return *this;
 }

#endif // _LIBCPP_HAS_NO_RVALUE_REFERENCES

 void lock();
 bool try_lock();

 template <class _Rep, class _Period>
 bool try_lock_for(const chrono::duration<_Rep, _Period>& __d);
 template <class _Clock, class _Duration>
 bool try_lock_until(const chrono::time_point<_Clock, _Duration>& __t);

 void unlock();

 _LIBCPP_INLINE_VISIBILITY
 void swap(unique_lock& __u) _NOEXCEPT
 {
 _VSTD::swap(__m_, __u.__m_);
 _VSTD::swap(__owns_, __u.__owns_);
 }
 _LIBCPP_INLINE_VISIBILITY
 mutex_type* release() _NOEXCEPT
 {
 mutex_type* __m = __m_;
 __m_ = nullptr;
 __owns_ = false;
 return __m;
 }

 _LIBCPP_INLINE_VISIBILITY
 bool owns_lock() const _NOEXCEPT {return __owns_;}
 _LIBCPP_INLINE_VISIBILITY
 _LIBCPP_EXPLICIT
 operator bool () const _NOEXCEPT {return __owns_;}
 _LIBCPP_INLINE_VISIBILITY
 mutex_type* mutex() const _NOEXCEPT {return __m_;}
};

template <class _Mutex>
void
unique_lock<_Mutex>::lock()
{
 if (__m_ == nullptr)
 __throw_system_error(EPERM, "unique_lock::lock: references null mutex");
 if (__owns_)
 __throw_system_error(EDEADLK, "unique_lock::lock: already locked");
 __m_->lock();
 __owns_ = true;
}

template <class _Mutex>
bool
unique_lock<_Mutex>::try_lock()
{
 if (__m_ == nullptr)
 __throw_system_error(EPERM, "unique_lock::try_lock: references null mutex");
 if (__owns_)
 __throw_system_error(EDEADLK, "unique_lock::try_lock: already locked");
 __owns_ = __m_->try_lock();
 return __owns_;
}

template <class _Mutex>
template <class _Rep, class _Period>
bool
unique_lock<_Mutex>::try_lock_for(const chrono::duration<_Rep, _Period>& __d)
{
 if (__m_ == nullptr)
 __throw_system_error(EPERM, "unique_lock::try_lock_for: references null mutex");
 if (__owns_)
 __throw_system_error(EDEADLK, "unique_lock::try_lock_for: already locked");
 __owns_ = __m_->try_lock_for(__d);
 return __owns_;
}

template <class _Mutex>
template <class _Clock, class _Duration>
bool
unique_lock<_Mutex>::try_lock_until(const chrono::time_point<_Clock, _Duration>& __t)
{
 if (__m_ == nullptr)
 __throw_system_error(EPERM, "unique_lock::try_lock_until: references null mutex");
 if (__owns_)
 __throw_system_error(EDEADLK, "unique_lock::try_lock_until: already locked");
 __owns_ = __m_->try_lock_until(__t);
 return __owns_;
}

template <class _Mutex>
void
unique_lock<_Mutex>::unlock()
{
 if (!__owns_)
 __throw_system_error(EPERM, "unique_lock::unlock: not locked");
 __m_->unlock();
 __owns_ = false;
}

template <class _Mutex>
inline _LIBCPP_INLINE_VISIBILITY
void
swap(unique_lock<_Mutex>& __x, unique_lock<_Mutex>& __y) _NOEXCEPT
 {__x.swap(__y);}

//enum class cv_status
_LIBCPP_DECLARE_STRONG_ENUM(cv_status)
{
 no_timeout,
 timeout
};
_LIBCPP_DECLARE_STRONG_ENUM_EPILOG(cv_status)

class _LIBCPP_TYPE_VIS condition_variable
{
#ifndef _LIBCPP_HAS_NO_CONSTEXPR
 __libcpp_condvar_t __cv_ = _LIBCPP_CONDVAR_INITIALIZER;
#else
 __libcpp_condvar_t __cv_;
#endif

public:
 _LIBCPP_INLINE_VISIBILITY
#ifndef _LIBCPP_HAS_NO_CONSTEXPR
 constexpr condition_variable() _NOEXCEPT _LIBCPP_DEFAULT
#else
 condition_variable() _NOEXCEPT {__cv_ = (__libcpp_condvar_t)_LIBCPP_CONDVAR_INITIALIZER;}
#endif
 ~condition_variable();

private:
 condition_variable(const condition_variable&); // = delete;
 condition_variable& operator=(const condition_variable&); // = delete;

public:
 void notify_one() _NOEXCEPT;
 void notify_all() _NOEXCEPT;

 void wait(unique_lock<mutex>& __lk) _NOEXCEPT;
 template <class _Predicate>
 void wait(unique_lock<mutex>& __lk, _Predicate __pred);

 template <class _Clock, class _Duration>
 cv_status
 wait_until(unique_lock<mutex>& __lk,
 const chrono::time_point<_Clock, _Duration>& __t);

 template <class _Clock, class _Duration, class _Predicate>
 bool
 wait_until(unique_lock<mutex>& __lk,
 const chrono::time_point<_Clock, _Duration>& __t,
 _Predicate __pred);

 template <class _Rep, class _Period>
 cv_status
 wait_for(unique_lock<mutex>& __lk,
 const chrono::duration<_Rep, _Period>& __d);

 template <class _Rep, class _Period, class _Predicate>
 bool
 _LIBCPP_INLINE_VISIBILITY
 wait_for(unique_lock<mutex>& __lk,
 const chrono::duration<_Rep, _Period>& __d,
 _Predicate __pred);

 typedef __libcpp_condvar_t* native_handle_type;
 _LIBCPP_INLINE_VISIBILITY native_handle_type native_handle() {return &__cv_;}

private:
 void __do_timed_wait(unique_lock<mutex>& __lk,
 chrono::time_point<chrono::system_clock, chrono::nanoseconds>) _NOEXCEPT;
};
#endif // !_LIBCPP_HAS_NO_THREADS

template <class _To, class _Rep, class _Period>
inline _LIBCPP_INLINE_VISIBILITY
typename enable_if
<
 chrono::__is_duration<_To>::value,
 _To
>::type
__ceil(chrono::duration<_Rep, _Period> __d)
{
 using namespace chrono;
 _To __r = duration_cast<_To>(__d);
 if (__r < __d)
 ++__r;
 return __r;
}

#ifndef _LIBCPP_HAS_NO_THREADS
template <class _Predicate>
void
condition_variable::wait(unique_lock<mutex>& __lk, _Predicate __pred)
{
 while (!__pred())
 wait(__lk);
}

template <class _Clock, class _Duration>
cv_status
condition_variable::wait_until(unique_lock<mutex>& __lk,
 const chrono::time_point<_Clock, _Duration>& __t)
{
 using namespace chrono;
 wait_for(__lk, __t - _Clock::now());
 return _Clock::now() < __t ? cv_status::no_timeout : cv_status::timeout;
}

template <class _Clock, class _Duration, class _Predicate>
bool
condition_variable::wait_until(unique_lock<mutex>& __lk,
 const chrono::time_point<_Clock, _Duration>& __t,
 _Predicate __pred)
{
 while (!__pred())
 {
 if (wait_until(__lk, __t) == cv_status::timeout)
 return __pred();
 }
 return true;
}

template <class _Rep, class _Period>
cv_status
condition_variable::wait_for(unique_lock<mutex>& __lk,
 const chrono::duration<_Rep, _Period>& __d)
{
 using namespace chrono;
 if (__d <= __d.zero())
 return cv_status::timeout;
 typedef time_point<system_clock, duration<long double, nano> > __sys_tpf;
 typedef time_point<system_clock, nanoseconds> __sys_tpi;
 __sys_tpf _Max = __sys_tpi::max();
 system_clock::time_point __s_now = system_clock::now();
 steady_clock::time_point __c_now = steady_clock::now();
 if (_Max - __d > __s_now)
 __do_timed_wait(__lk, __s_now + __ceil<nanoseconds>(__d));
 else
 __do_timed_wait(__lk, __sys_tpi::max());
 return steady_clock::now() - __c_now < __d ? cv_status::no_timeout :
 cv_status::timeout;
}

template <class _Rep, class _Period, class _Predicate>
inline
bool
condition_variable::wait_for(unique_lock<mutex>& __lk,
 const chrono::duration<_Rep, _Period>& __d,
 _Predicate __pred)
{
 return wait_until(__lk, chrono::steady_clock::now() + __d,
 _VSTD::move(__pred));
}

#endif // !_LIBCPP_HAS_NO_THREADS

_LIBCPP_END_NAMESPACE_STD

#endif // _LIBCPP___MUTEX_BASE