norm_engine.hpp

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#ifndef __ZMQ_NORM_ENGINE_HPP_INCLUDED__
#define __ZMQ_NORM_ENGINE_HPP_INCLUDED__
 
#if defined ZMQ_HAVE_NORM
 
#if defined(ZMQ_HAVE_WINDOWS) && defined(ZMQ_IOTHREAD_POLLER_USE_EPOLL)
#define ZMQ_USE_NORM_SOCKET_WRAPPER
#endif
 
 
#include "io_object.hpp"
#include "i_engine.hpp"
#include "options.hpp"
#include "v2_decoder.hpp"
#include "v2_encoder.hpp"
 
#include <normApi.h>
 
namespace zmq
{
class io_thread_t;
class msg_t;
class session_base_t;
 
class norm_engine_t ZMQ_FINAL : public io_object_t, public i_engine
{
  public:
    norm_engine_t (zmq::io_thread_t *parent_, const options_t &options_);
    ~norm_engine_t () ZMQ_FINAL;
 
    // create NORM instance, session, etc
    int init (const char *network_, bool send, bool recv);
    void shutdown ();
 
    bool has_handshake_stage () ZMQ_FINAL { return false; };
 
    //  i_engine interface implementation.
    //  Plug the engine to the session.
    void plug (zmq::io_thread_t *io_thread_,
               class session_base_t *session_) ZMQ_FINAL;
 
    //  Terminate and deallocate the engine. Note that 'detached'
    //  events are not fired on termination.
    void terminate () ZMQ_FINAL;
 
    //  This method is called by the session to signalise that more
    //  messages can be written to the pipe.
    bool restart_input () ZMQ_FINAL;
 
    //  This method is called by the session to signalise that there
    //  are messages to send available.
    void restart_output () ZMQ_FINAL;
 
    void zap_msg_available () ZMQ_FINAL {}
 
    const endpoint_uri_pair_t &get_endpoint () const ZMQ_FINAL;
 
    // i_poll_events interface implementation.
    // (we only need in_event() for NormEvent notification)
    // (i.e., don't have any output events or timers (yet))
    void in_event ();
 
  private:
    void unplug ();
    void send_data ();
    void recv_data (NormObjectHandle stream);
 
 
    enum
    {
        BUFFER_SIZE = 2048
    };
 
    // Used to keep track of streams from multiple senders
    class NormRxStreamState
    {
      public:
        NormRxStreamState (NormObjectHandle normStream,
                           int64_t maxMsgSize,
                           bool zeroCopy,
                           int inBatchSize);
        ~NormRxStreamState ();
 
        NormObjectHandle GetStreamHandle () const { return norm_stream; }
 
        bool Init ();
 
        void SetRxReady (bool state) { rx_ready = state; }
        bool IsRxReady () const { return rx_ready; }
 
        void SetSync (bool state) { in_sync = state; }
        bool InSync () const { return in_sync; }
 
        // These are used to feed data to decoder
        // and its underlying "msg" buffer
        char *AccessBuffer () { return (char *) (buffer_ptr + buffer_count); }
        size_t GetBytesNeeded () const { return buffer_size - buffer_count; }
        void IncrementBufferCount (size_t count) { buffer_count += count; }
        msg_t *AccessMsg () { return zmq_decoder->msg (); }
        // This invokes the decoder "decode" method
        // returning 0 if more data is needed,
        // 1 if the message is complete, If an error
        // occurs the 'sync' is dropped and the
        // decoder re-initialized
        int Decode ();
 
        class List
        {
          public:
            List ();
            ~List ();
 
            void Append (NormRxStreamState &item);
            void Remove (NormRxStreamState &item);
 
            bool IsEmpty () const { return NULL == head; }
 
            void Destroy ();
 
            class Iterator
            {
              public:
                Iterator (const List &list);
                NormRxStreamState *GetNextItem ();
 
              private:
                NormRxStreamState *next_item;
            };
            friend class Iterator;
 
          private:
            NormRxStreamState *head;
            NormRxStreamState *tail;
 
        }; // end class zmq::norm_engine_t::NormRxStreamState::List
 
        friend class List;
 
        List *AccessList () { return list; }
 
 
      private:
        NormObjectHandle norm_stream;
        int64_t max_msg_size;
        bool zero_copy;
        int in_batch_size;
        bool in_sync;
        bool rx_ready;
        v2_decoder_t *zmq_decoder;
        bool skip_norm_sync;
        unsigned char *buffer_ptr;
        size_t buffer_size;
        size_t buffer_count;
 
        NormRxStreamState *prev;
        NormRxStreamState *next;
        NormRxStreamState::List *list;
 
    }; // end class zmq::norm_engine_t::NormRxStreamState
 
    const endpoint_uri_pair_t _empty_endpoint;
 
    session_base_t *zmq_session;
    options_t options;
    NormInstanceHandle norm_instance;
    handle_t norm_descriptor_handle;
    NormSessionHandle norm_session;
    bool is_sender;
    bool is_receiver;
    // Sender state
    msg_t tx_msg;
    v2_encoder_t zmq_encoder; // for tx messages (we use v2 for now)
    NormObjectHandle norm_tx_stream;
    bool tx_first_msg;
    bool tx_more_bit;
    bool zmq_output_ready; // zmq has msg(s) to send
    bool norm_tx_ready;    // norm has tx queue vacancy
    // TBD - maybe don't need buffer if can access zmq message buffer directly?
    char tx_buffer[BUFFER_SIZE];
    unsigned int tx_index;
    unsigned int tx_len;
 
    // Receiver state
    // Lists of norm rx streams from remote senders
    bool zmq_input_ready; // zmq ready to receive msg(s)
    NormRxStreamState::List
      rx_pending_list; // rx streams waiting for data reception
    NormRxStreamState::List
      rx_ready_list; // rx streams ready for NormStreamRead()
    NormRxStreamState::List
      msg_ready_list; // rx streams w/ msg ready for push to zmq
 
#ifdef ZMQ_USE_NORM_SOCKET_WRAPPER
    fd_t
      wrapper_read_fd; // filedescriptor used to read norm events through the wrapper
    DWORD wrapper_thread_id;
    HANDLE wrapper_thread_handle;
#endif
 
}; // end class norm_engine_t
}
 
#endif // ZMQ_HAVE_NORM
 
#endif // !__ZMQ_NORM_ENGINE_HPP_INCLUDED__