pgm_receiver.hpp

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

#ifndef __ZMQ_PGM_RECEIVER_HPP_INCLUDED__
#define __ZMQ_PGM_RECEIVER_HPP_INCLUDED__

#if defined ZMQ_HAVE_OPENPGM

#include <map>
#include <algorithm>

#include "io_object.hpp"
#include "i_engine.hpp"
#include "options.hpp"
#include "v1_decoder.hpp"
#include "pgm_socket.hpp"

namespace zmq
{
class io_thread_t;
class session_base_t;

class pgm_receiver_t ZMQ_FINAL : public io_object_t, public i_engine
{
  public:
    pgm_receiver_t (zmq::io_thread_t *parent_, const options_t &options_);
    ~pgm_receiver_t ();

    int init (bool udp_encapsulation_, const char *network_);

    //  i_engine interface implementation.
    bool has_handshake_stage () { return false; };
    void plug (zmq::io_thread_t *io_thread_, zmq::session_base_t *session_);
    void terminate ();
    bool restart_input ();
    void restart_output ();
    void zap_msg_available () {}
    const endpoint_uri_pair_t &get_endpoint () const;

    //  i_poll_events interface implementation.
    void in_event ();
    void timer_event (int token);

  private:
    //  Unplug the engine from the session.
    void unplug ();

    //  Decode received data (inpos, insize) and forward decoded
    //  messages to the session.
    int process_input (v1_decoder_t *decoder);

    //  PGM is not able to move subscriptions upstream. Thus, drop all
    //  the pending subscriptions.
    void drop_subscriptions ();

    //  RX timeout timer ID.
    enum
    {
        rx_timer_id = 0xa1
    };

    const endpoint_uri_pair_t _empty_endpoint;

    //  RX timer is running.
    bool has_rx_timer;

    //  If joined is true we are already getting messages from the peer.
    //  It it's false, we are getting data but still we haven't seen
    //  beginning of a message.
    struct peer_info_t
    {
        bool joined;
        v1_decoder_t *decoder;
    };

    struct tsi_comp
    {
        bool operator() (const pgm_tsi_t &ltsi, const pgm_tsi_t &rtsi) const
        {
            uint32_t ll[2], rl[2];
            memcpy (ll, &ltsi, sizeof (ll));
            memcpy (rl, &rtsi, sizeof (rl));
            return (ll[0] < rl[0]) || (ll[0] == rl[0] && ll[1] < rl[1]);
        }
    };

    typedef std::map<pgm_tsi_t, peer_info_t, tsi_comp> peers_t;
    peers_t peers;

    //  PGM socket.
    pgm_socket_t pgm_socket;

    //  Socket options.
    options_t options;

    //  Associated session.
    zmq::session_base_t *session;

    const pgm_tsi_t *active_tsi;

    //  Number of bytes not consumed by the decoder due to pipe overflow.
    size_t insize;

    //  Pointer to data still waiting to be processed by the decoder.
    const unsigned char *inpos;

    //  Poll handle associated with PGM socket.
    handle_t socket_handle;

    //  Poll handle associated with engine PGM waiting pipe.
    handle_t pipe_handle;

    ZMQ_NON_COPYABLE_NOR_MOVABLE (pgm_receiver_t)
};
}

#endif

#endif