condition_variable_wrapper_impl.hpp

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#include "mysql/concurrency/condition_variable_wrapper.h"
 
namespace mysql::concurrency {
 
template <class Predicate>
void Condition_variable_wrapper::wait(std::unique_lock<Mutex_wrapper> &lock,
                                      Predicate pred) {
  while (!pred()) {
    mysql_cond_wait(&m_cv, lock.mutex()->native_handle());
  }
}
 
template <class Rep, class Period, class Predicate>
bool Condition_variable_wrapper::wait_for(
    std::unique_lock<Mutex_wrapper> &lock,
    const std::chrono::duration<Rep, Period> &rel_time, Predicate pred) {
  struct timespec tm;
  auto end_time = std::chrono::system_clock::now() + rel_time;
  tm.tv_sec = std::chrono::system_clock::to_time_t(end_time);
  auto ns = std::chrono::duration_cast<std::chrono::nanoseconds>(
                end_time.time_since_epoch())
                .count() %
            1000000000;
  tm.tv_nsec = ns;
  bool last_pred_value{false};
  bool timeout = false;
  while (!(last_pred_value = pred()) && !timeout) {
    timeout = mysql_cond_timedwait(&m_cv, lock.mutex()->native_handle(), &tm);
  }
  return last_pred_value;
}
 
template <class Rep, class Period>
std::cv_status Condition_variable_wrapper::wait_for(
    std::unique_lock<Mutex_wrapper> &lock,
    const std::chrono::duration<Rep, Period> &rel_time) {
  struct timespec tm;
  auto end_time = std::chrono::system_clock::now() + rel_time;
  tm.tv_sec = std::chrono::system_clock::to_time_t(end_time);
  auto ns = std::chrono::duration_cast<std::chrono::nanoseconds>(
                end_time.time_since_epoch())
                .count() %
            1000000000;
  tm.tv_nsec = ns;
  return mysql_cond_timedwait(&m_cv, lock.mutex()->native_handle(), &tm)
             ? std::cv_status::timeout
             : std::cv_status::no_timeout;
}
 
template <class Clock, class Duration, class Predicate>
bool Condition_variable_wrapper::wait_until(
    std::unique_lock<Mutex_wrapper> &lock,
    const std::chrono::time_point<Clock, Duration> &abs_time, Predicate pred) {
  struct timespec tm;
  tm.tv_sec = Clock::to_time_t(abs_time);
  auto ns = std::chrono::duration_cast<std::chrono::nanoseconds>(
                abs_time.time_since_epoch())
                .count() %
            1000000000;
  tm.tv_nsec = ns;
  bool timeout = false;
  bool last_pred_value = false;
  while (!(last_pred_value = pred()) && !timeout) {
    timeout = mysql_cond_timedwait(&m_cv, lock.mutex()->native_handle(), &tm);
  }
  return last_pred_value;
}
 
template <class Clock, class Duration>
std::cv_status Condition_variable_wrapper::wait_until(
    std::unique_lock<Mutex_wrapper> &lock,
    const std::chrono::time_point<Clock, Duration> &abs_time) {
  struct timespec tm;
  tm.tv_sec = Clock::to_time_t(abs_time);
  auto ns = std::chrono::duration_cast<std::chrono::nanoseconds>(
                abs_time.time_since_epoch())
                .count() %
            1000000000;
  tm.tv_nsec = ns;
  return mysql_cond_timedwait(&m_cv, lock.mutex()->native_handle(), &tm)
             ? std::cv_status::timeout
             : std::cv_status::no_timeout;
}
 
}  // namespace mysql::concurrency