timers.hpp

/* SPDX-License-Identifier: MPL-2.0 */

#ifndef __ZMQ_TIMERS_HPP_INCLUDED__
#define __ZMQ_TIMERS_HPP_INCLUDED__

#include <stddef.h>
#include <map>
#include <set>

#include "clock.hpp"

namespace zmq
{
typedef void (timers_timer_fn) (int timer_id_, void *arg_);

class timers_t
{
  public:
    timers_t ();
    ~timers_t ();

    //  Add timer to the set, timer repeats forever, or until cancel is called.
    //  Returns a timer_id that is used to cancel the timer.
    //  Returns -1 if there was an error.
    int add (size_t interval_, timers_timer_fn handler_, void *arg_);

    //  Set the interval of the timer.
    //  This method is slow, cancelling exsting and adding a new timer yield better performance.
    //  Returns 0 on success and -1 on error.
    int set_interval (int timer_id_, size_t interval_);

    //  Reset the timer.
    //  This method is slow, cancelling exsting and adding a new timer yield better performance.
    //  Returns 0 on success and -1 on error.
    int reset (int timer_id_);

    //  Cancel a timer.
    //  Returns 0 on success and -1 on error.
    int cancel (int timer_id_);

    //  Returns the time in millisecond until the next timer.
    //  Returns -1 if no timer is due.
    long timeout ();

    //  Execute timers.
    //  Return 0 if all succeed and -1 if error.
    int execute ();

    //  Return false if object is not a timers class.
    bool check_tag () const;

  private:
    //  Used to check whether the object is a timers class.
    uint32_t _tag;

    int _next_timer_id;

    //  Clock instance.
    clock_t _clock;

    typedef struct timer_t
    {
        int timer_id;
        size_t interval;
        timers_timer_fn *handler;
        void *arg;
    } timer_t;

    typedef std::multimap<uint64_t, timer_t> timersmap_t;
    timersmap_t _timers;

    typedef std::set<int> cancelled_timers_t;
    cancelled_timers_t _cancelled_timers;

    struct match_by_id;

    ZMQ_NON_COPYABLE_NOR_MOVABLE (timers_t)
};
}

#endif