sdo.h

/*
 * Copyright (c) 2015, Thomas Keh
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *    1. Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *
 *    2. Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *
 *    3. Neither the name of the copyright holder nor the names of its
 *       contributors may be used to endorse or promote products derived from
 *       this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
 
#pragma once

#include <functional>
#include <vector>
#include <mutex>
#include <list>
#include <unordered_map>

#include "message.h"
#include "sdo_response.h"

namespace kaco {
    
    // forward declaration
    class Core;

    class SDO {

    public:

        using SDOReceivedCallback = std::function< void(SDOResponse) >;

        SDO(Core& core);

        SDO(const SDO&) = delete;
        
        void download(uint8_t node_id, uint16_t index, uint8_t subindex, uint32_t size, const std::vector<uint8_t>& bytes);
        
        std::vector<uint8_t> upload(uint8_t node_id, uint16_t index, uint8_t subindex);

        void process_incoming_message(const Message& message);

        SDOResponse send_sdo_and_wait(uint8_t command, uint8_t node_id, uint16_t index, uint8_t subindex, const std::array<uint8_t,4>& data);

    private:

        enum Flag : uint8_t {

            // client command specifiers
            initiate_download_request = 0x20,
            download_segment_request = 0x00,
            initiate_upload_request = 0x40,
            upload_segment_request = 0x60,

            // server command specifiers
            initiate_download_response = 0x60,
            download_segment_response = 0x20,
            initiate_upload_response = 0x40,
            upload_segment_response = 0x00,

            toggle_bit = 0x10,
            no_more_segments = 0x01,
            size_indicated = 0x01,
            expedited_transfer = 0x02,

            error = 0x80

        };

        static const bool debug = false;
        
        Core& m_core;

        // Recevicers on per-node basis. Never call send_sdo_and_wait() from inside!
        // TODO: Add m_server_sdo_callbacks and add m_client_sdo_callbacks for custom usage.
        // IDEA: We could store the promise directly, but this won't obviate synchronization...
        std::array<SDOReceivedCallback,256> m_send_and_wait_receivers;

        // We must synchronize access to the m_send_and_wait_receivers array entries.
        mutable std::array<std::mutex,256> m_send_and_wait_receiver_mutexes;

        // We lock send_sdo_and_wait() on per-node basis because concurrent responses could be confused
        // and because m_receivers manipulation must be synchronized
        mutable std::array<std::mutex,256> m_send_and_wait_mutex;

        uint8_t size_flag(uint8_t size);

        static void received_unassigned_sdo(SDOResponse);

    };

} // end namespace kaco