packet_iterator.hpp

// Copyright Takatoshi Kondo 2022
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
 
#if !defined(ASYNC_MQTT_PACKET_PACKET_ITERATOR_HPP)
#define ASYNC_MQTT_PACKET_PACKET_ITERATOR_HPP
 
#include <vector>
#include <tuple>
#include <string>
 
#include <boost/asio/buffer.hpp>
#include <boost/asio/buffers_iterator.hpp>
 
#include <async_mqtt/buffer.hpp>
 
namespace async_mqtt {
 
namespace as = boost::asio;
 
template <template <typename...> typename Container, typename Buffer>
using packet_iterator = as::buffers_iterator<Container<Buffer>>;
 
template <template <typename...> typename Container, typename Buffer>
std::pair<packet_iterator<Container, Buffer>, packet_iterator<Container, Buffer>>
make_packet_range(Container<Buffer> const& cbs) {
    return {
        packet_iterator<Container, Buffer>::begin(cbs),
        packet_iterator<Container, Buffer>::end(cbs)
    };
}
 
template <template <typename...> typename Container, typename Buffer>
std::string
to_string(Container<Buffer> const& cbs) {
    auto [b, e] = make_packet_range(cbs);
    return std::string(b, e);
}
 
template <template <typename...> typename Container, typename Buffer>
buffer
to_buffer(Container<Buffer> const& cbs) {
    switch (cbs.size()) {
    case 0: return buffer{};
    case 1: return cbs.front();
    default: {
        auto [b, e] = make_packet_range(cbs);
        return allocate_buffer(b, e);
    }
    }
}
 
} // namespace async_mqtt
 
#endif // ASYNC_MQTT_PACKET_PACKET_ITERATOR_HPP