PrusaSlicer-NonPlainar/src/libslic3r/Channel.hpp
2018-12-20 13:38:00 +01:00

102 lines
2.6 KiB
C++

#ifndef slic3r_Channel_hpp_
#define slic3r_Channel_hpp_
#include <memory>
#include <deque>
#include <condition_variable>
#include <mutex>
#include <utility>
#include <boost/optional.hpp>
namespace Slic3r {
template<class T> class Channel
{
public:
using UniqueLock = std::unique_lock<std::mutex>;
template<class Ptr> class Unlocker
{
public:
Unlocker(UniqueLock lock) : m_lock(std::move(lock)) {}
Unlocker(const Unlocker &other) noexcept : m_lock(std::move(other.m_lock)) {} // XXX: done beacuse of MSVC 2013 not supporting init of deleter by move
Unlocker(Unlocker &&other) noexcept : m_lock(std::move(other.m_lock)) {}
Unlocker& operator=(const Unlocker &other) = delete;
Unlocker& operator=(Unlocker &&other) { m_lock = std::move(other.m_lock); }
void operator()(Ptr*) { m_lock.unlock(); }
private:
mutable UniqueLock m_lock; // XXX: mutable: see above
};
using Queue = std::deque<T>;
using LockedConstPtr = std::unique_ptr<const Queue, Unlocker<const Queue>>;
using LockedPtr = std::unique_ptr<Queue, Unlocker<Queue>>;
Channel() {}
~Channel() {}
void push(const T& item, bool silent = false)
{
{
UniqueLock lock(m_mutex);
m_queue.push_back(item);
}
if (! silent) { m_condition.notify_one(); }
}
void push(T &&item, bool silent = false)
{
{
UniqueLock lock(m_mutex);
m_queue.push_back(std::forward<T>(item));
}
if (! silent) { m_condition.notify_one(); }
}
T pop()
{
UniqueLock lock(m_mutex);
m_condition.wait(lock, [this]() { return !m_queue.empty(); });
auto item = std::move(m_queue.front());
m_queue.pop_front();
return item;
}
boost::optional<T> try_pop()
{
UniqueLock lock(m_mutex);
if (m_queue.empty()) {
return boost::none;
} else {
auto item = std::move(m_queue.front());
m_queue.pop();
return item;
}
}
// Unlocked observer/hint. Thread unsafe! Keep in mind you need to re-verify the result after locking.
size_t size_hint() const noexcept { return m_queue.size(); }
LockedConstPtr lock_read() const
{
return LockedConstPtr(&m_queue, Unlocker<const Queue>(UniqueLock(m_mutex)));
}
LockedPtr lock_rw()
{
return LockedPtr(&m_queue, Unlocker<Queue>(UniqueLock(m_mutex)));
}
private:
Queue m_queue;
mutable std::mutex m_mutex;
std::condition_variable m_condition;
};
} // namespace Slic3r
#endif // slic3r_Channel_hpp_