uhd/host/lib/include/uhdlib/utils/atomic.hpp
Martin Braun ee520a9df5 uhd: Apply clang-format against all .cpp and .hpp files in host/
Note: template_lvbitx.{cpp,hpp} need to be excluded from the
list of files that clang-format gets applied against.
host/lib/dep is also excluded from this change.
2020-04-17 15:02:40 -07:00

77 lines
1.9 KiB
C++

//
// Copyright 2012-2013,2016-2017 Ettus Research LLC
// Copyright 2018 Ettus Research, a National Instruments Company
//
// SPDX-License-Identifier: GPL-3.0-or-later
//
#ifndef INCLUDED_UHD_UTILS_ATOMIC_HPP
#define INCLUDED_UHD_UTILS_ATOMIC_HPP
#include <uhd/config.hpp>
#include <uhd/types/time_spec.hpp>
#include <uhdlib/utils/system_time.hpp>
#include <boost/thread/thread.hpp>
#include <atomic>
namespace uhd {
/*! DEPRECATED -- Will be removed in coming versions of UHD.
*
* Spin-wait on a condition with a timeout.
* \param cond an atomic variable to compare
* \param value compare to atomic for true/false
* \param timeout the timeout in seconds
* \return true for cond == value, false for timeout
*/
template <typename T>
UHD_INLINE bool spin_wait_with_timeout(
std::atomic<T>& cond, const T value, const double timeout)
{
if (cond == value)
return true;
const time_spec_t exit_time = uhd::get_system_time() + time_spec_t(timeout);
while (cond != value) {
if (uhd::get_system_time() > exit_time) {
return false;
}
boost::this_thread::interruption_point();
boost::this_thread::yield();
}
return true;
}
/*! DEPRECATED -- Will be removed in coming versions of UHD.
*
* Claimer class to provide synchronization for multi-thread access.
* Claiming enables buffer classes to be used with a buffer queue.
*/
class simple_claimer
{
public:
simple_claimer(void)
{
this->release();
}
UHD_INLINE void release(void)
{
_locked = false;
}
UHD_INLINE bool claim_with_wait(const double timeout)
{
if (spin_wait_with_timeout(_locked, false, timeout)) {
_locked = true;
return true;
}
return false;
}
private:
std::atomic<bool> _locked;
};
} // namespace uhd
#endif /* INCLUDED_UHD_UTILS_ATOMIC_HPP */