timer.hpp

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// nros-cpp: Timer class
// Freestanding C++ — no exceptions, no STL required
 
#ifndef NROS_CPP_TIMER_HPP
#define NROS_CPP_TIMER_HPP
 
#include <cstdint>
#include <cstddef>
 
#include "nros/result.hpp"
 
#ifdef NROS_CPP_STD
#include <functional>
#include <memory>
#endif
 
#include "nros_cpp_ffi.h"
 
namespace nros {
 
class Timer {
  public:
    Result cancel() {
        if (!initialized_) return Result(ErrorCode::NotInitialized);
        return Result(nros_cpp_timer_cancel(executor_, handle_id_));
    }
 
    Result reset() {
        if (!initialized_) return Result(ErrorCode::NotInitialized);
        return Result(nros_cpp_timer_reset(executor_, handle_id_));
    }
 
    bool is_cancelled() const {
        if (!initialized_) return true;
        return nros_cpp_timer_is_cancelled(executor_, handle_id_);
    }
 
    bool is_valid() const { return initialized_; }
 
    ~Timer() {
        if (initialized_) {
            nros_cpp_timer_cancel(executor_, handle_id_);
            initialized_ = false;
        }
        // closure_ (if any) destructs here; the runtime no longer
        // holds a raw pointer to it because we cancelled above.
    }
 
    // Move semantics (non-copyable)
    Timer(Timer&& other)
        : executor_(other.executor_), handle_id_(other.handle_id_), initialized_(other.initialized_)
#ifdef NROS_CPP_STD
          ,
          closure_(std::move(other.closure_))
#endif
    {
        other.executor_ = nullptr;
        other.initialized_ = false;
    }
 
    Timer& operator=(Timer&& other) {
        if (this != &other) {
            if (initialized_) {
                nros_cpp_timer_cancel(executor_, handle_id_);
            }
            executor_ = other.executor_;
            handle_id_ = other.handle_id_;
            initialized_ = other.initialized_;
#ifdef NROS_CPP_STD
            closure_ = std::move(other.closure_);
#endif
            other.executor_ = nullptr;
            other.initialized_ = false;
        }
        return *this;
    }
 
    Timer() : executor_(nullptr), handle_id_(0), initialized_(false) {}
 
#ifdef NROS_CPP_STD
    void attach_std_closure(std::unique_ptr<std::function<void()>> closure) {
        closure_ = std::move(closure);
    }
#endif
 
  private:
    Timer(const Timer&) = delete;
    Timer& operator=(const Timer&) = delete;
 
    friend class Node;
 
    void* executor_;
    size_t handle_id_;
    bool initialized_;
 
#ifdef NROS_CPP_STD
    std::unique_ptr<std::function<void()>> closure_;
#endif
};
 
} // namespace nros
 
#endif // NROS_CPP_TIMER_HPP