CNTRIPClient.cpp

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2020, Individual contributors, see AUTHORS file     |
   | See: https://www.mrpt.org/Authors - All rights reserved.               |
   | Released under BSD License. See: https://www.mrpt.org/License          |
   +------------------------------------------------------------------------+ */

#include "hwdrivers-precomp.h"  // Precompiled headers

#include <mrpt/comms/CClientTCPSocket.h>
#include <mrpt/comms/net_utils.h>
#include <mrpt/core/bits_math.h>
#include <mrpt/core/format.h>
#include <mrpt/hwdrivers/CNTRIPClient.h>
#include <mrpt/math/wrap2pi.h>
#include <mrpt/system/string_utils.h>
#include <cstring>
#include <iostream>

using namespace mrpt;
using namespace mrpt::comms;
using namespace mrpt::system;
using namespace mrpt::hwdrivers;
using namespace mrpt::math;
using namespace std;

/* --------------------------------------------------------
                    CNTRIPClient
   -------------------------------------------------------- */
CNTRIPClient::CNTRIPClient() : m_thread(), m_args()
{
    m_thread = std::thread(&CNTRIPClient::private_ntrip_thread, this);
}

/* --------------------------------------------------------
                    ~CNTRIPClient
   -------------------------------------------------------- */
CNTRIPClient::~CNTRIPClient()
{
    this->close();
    if (m_thread.joinable())
    {
        m_thread_exit = true;
        m_thread.join();
    }
}

/* --------------------------------------------------------
                    close
   -------------------------------------------------------- */
void CNTRIPClient::close()
{
    m_upload_data.clear();
    if (!m_thread_do_process) return;
    m_thread_do_process = false;
    m_sem_sock_closed.get_future().wait_for(500ms);
}

/* --------------------------------------------------------
                    open
   -------------------------------------------------------- */
bool CNTRIPClient::open(const NTRIPArgs& params, string& out_errmsg)
{
    this->close();

    if (params.mountpoint.empty())
    {
        out_errmsg = "MOUNTPOINT cannot be empty.";
        return false;
    }
    if (params.server.empty())
    {
        out_errmsg = "Server address cannot be empty.";
        return false;
    }

    // Try to open it:
    m_waiting_answer_connection = true;
    m_answer_connection = connError;
    out_errmsg.clear();

    m_args = params;
    m_thread_do_process = true;

    // Wait until the thread tell us the initial result...
    if (m_sem_first_connect_done.get_future().wait_for(6s) ==
        std::future_status::timeout)
    {
        out_errmsg = "Timeout waiting thread response";
        return false;
    }

    switch (m_answer_connection)
    {
        case connOk:
            return true;
        case connError:
            out_errmsg = format(
                "Error trying to connect to server '%s'",
                params.server.c_str());
            return false;
        case connUnauthorized:
            out_errmsg = format(
                "Authentication failed for server '%s'", params.server.c_str());
            return false;

        default:
            out_errmsg = "UNKNOWN m_answer_connection!!";
            return false;
    }
}

/* --------------------------------------------------------
                    THE WORKING THREAD
   -------------------------------------------------------- */
void CNTRIPClient::private_ntrip_thread()
{
    try
    {
        CClientTCPSocket my_sock;

        bool last_thread_do_process = m_thread_do_process;

        while (!m_thread_exit)
        {
            if (!m_thread_do_process)
            {
                if (my_sock.isConnected())
                {
                    // Close connection:
                    try
                    {
                        my_sock.close();
                    }
                    catch (...)
                    {
                    }
                }
                else
                {
                    // Nothing to be done... just wait
                }

                if (last_thread_do_process)  // Let the waiting caller continue
                    // now.
                    m_sem_sock_closed.set_value();

                last_thread_do_process = m_thread_do_process;
                std::this_thread::sleep_for(100ms);
                continue;
            }

            last_thread_do_process = m_thread_do_process;

            // We have a mission to do here... is the channel already open??

            if (!my_sock.isConnected())
            {
                TConnResult connect_res = connError;

                std::vector<uint8_t> buf;
                try
                {
                    // Nope, it's the first time: get params and try open the
                    // connection:
                    stream_data.clear();

                    cout << format(
                        "[CNTRIPClient] Trying to connect to %s:%i\n",
                        m_args.server.c_str(), m_args.port);

                    my_sock.connect(m_args.server, m_args.port);
                    if (m_thread_exit) break;

                    // Prepare HTTP request:
                    // -------------------------------------------
                    string req = format(
                        "GET /%s HTTP/1.0\r\n", m_args.mountpoint.c_str());

                    if (isalpha(m_args.server[0]))
                        req += format("Host: %s\r\n", m_args.server.c_str());

                    req += "User-Agent: NTRIP MRPT Library\r\n";
                    req += "Accept: */*\r\n";
                    req += "Connection: close\r\n";

                    // Implement HTTP Basic authentication:
                    // See:
                    // http://en.wikipedia.org/wiki/Basic_access_authentication
                    if (!m_args.user.empty())
                    {
                        string auth_str =
                            m_args.user + string(":") + m_args.password;
                        std::vector<uint8_t> v(auth_str.size());
                        std::memcpy(&v[0], &auth_str[0], auth_str.size());

                        string encoded_str;
                        mrpt::system::encodeBase64(v, encoded_str);

                        req += "Authorization: Basic ";
                        req += encoded_str;
                        req += "\r\n";
                    }

                    // End:
                    req += "\r\n";
                    // cout << req;

                    // Send:
                    my_sock.sendString(req);

                    // Try to read the header of the response:
                    size_t to_read_now = 30;
                    buf.resize(to_read_now);
                    size_t len =
                        my_sock.readAsync(&buf[0], to_read_now, 4000, 200);

                    buf.resize(len);

                    if ((len != 0) && my_sock.isConnected())
                        connect_res = connOk;
                }
                catch (std::exception&)
                {
                    // cout << e.what() << endl;
                    connect_res = connError;
                }

                // We are not disconnected yet, it's a good thing... anyway,
                // check the answer code:
                if (!buf.empty())
                {
                    string resp;
                    resp.resize(buf.size());
                    std::memcpy(&resp[0], &buf[0], buf.size());

                    if (resp.find(" 200 ") == string::npos)
                    {
                        // It's NOT a good response...
                        connect_res = connError;

                        // 401?
                        if (resp.find(" 401 ") != string::npos)
                            connect_res = connUnauthorized;
                    }
                }

                // Signal my caller that the connection is established:
                // ---------------------------------------------------------------
                if (m_waiting_answer_connection)
                {
                    m_waiting_answer_connection = false;

                    m_answer_connection = connect_res;
                    m_sem_first_connect_done.set_value();
                }

                if (connect_res != connOk) my_sock.close();
            }

            // Retry if it was a failed connection.
            if (!my_sock.isConnected())
            {
                std::this_thread::sleep_for(500ms);
                continue;
            }

            // Read data from the stream and accumulate it in a buffer:
            // ----------------------------------------------------------------------
            std::vector<uint8_t> buf;
            size_t to_read_now = 1000;
            buf.resize(to_read_now);
            size_t len = my_sock.readAsync(&buf[0], to_read_now, 10, 5);

            buf.resize(len);

            if (my_sock.isConnected())
            {
                // Send data to main buffer:
                if (stream_data.size() > 1024 * 8)
                    stream_data.clear();  // It seems nobody's reading it...

                stream_data.appendData(buf);
                buf.clear();
            }

            // Send back data to the server, if so requested:
            // ------------------------------------------
            std::vector<uint8_t> upload_data;
            m_upload_data.readAndClear(upload_data);
            if (!upload_data.empty())
            {
                const size_t N = upload_data.size();
                const size_t nWritten =
                    my_sock.writeAsync(&upload_data[0], N, 1000);
                if (nWritten != N)
                    cerr << "*ERROR*: Couldn't write back " << N
                         << " bytes to NTRIP server!.\n";
            }

            std::this_thread::sleep_for(10ms);
        }  // end while

    }  // end try
    catch (exception& e)
    {
        cerr << "[CNTRIPClient] Exception in working thread: " << endl
             << e.what() << endl;
    }
    catch (...)
    {
        cerr << "[CNTRIPClient] Runtime exception in working thread." << endl;
    }

}  // end working thread

/* --------------------------------------------------------
                    retrieveListOfMountpoints
   -------------------------------------------------------- */
bool CNTRIPClient::retrieveListOfMountpoints(
    TListMountPoints& out_list, string& out_errmsg, const string& server,
    int port, const string& auth_user, const string& auth_pass)
{
    string content;
    int http_code;
    TParameters<string> my_headers;

    out_list.clear();

    net::ERRORCODE_HTTP ret = net::http_get(
        string("http://") + server, content, out_errmsg, port, auth_user,
        auth_pass, &http_code, &my_headers, nullptr, 6000);

    // Parse contents:
    if (ret != net::erOk) return false;

    std::stringstream ss(content);
    string lin;
    while (std::getline(ss, lin, '\n'))
    {
        if (lin.size() < 5) continue;
        if (0 != ::strncmp("STR;", lin.c_str(), 4)) continue;

        // ok, it's a stream:
        deque<string> fields;
        mrpt::system::tokenize(lin, ";", fields);

        if (fields.size() < 13) continue;

        TMountPoint mnt;

        mnt.mountpoint_name = fields[1];
        mnt.id = fields[2];
        mnt.format = fields[3];
        mnt.format_details = fields[4];
        mnt.carrier = atoi(fields[5].c_str());
        mnt.nav_system = fields[6];
        mnt.network = fields[7];
        mnt.country_code = fields[8];
        mnt.latitude = atof(fields[9].c_str());
        mnt.longitude = atof(fields[10].c_str());

        // Longitude in range: -180,180
        mnt.longitude = RAD2DEG(mrpt::math::wrapToPi(DEG2RAD(mnt.longitude)));

        mnt.needs_nmea = atoi(fields[11].c_str()) != 0;
        mnt.net_ref_stations = atoi(fields[12].c_str()) != 0;

        if (fields.size() >= 19) mnt.extra_info = fields[18];

        out_list.push_back(mnt);
    }

    return true;
}

/** Enqueues a string to be sent back to the NTRIP server (e.g. GGA frames) */
void CNTRIPClient::sendBackToServer(const std::string& data)
{
    if (data.empty()) return;

    std::vector<uint8_t> d(data.size());
    std::memcpy(&d[0], &data[0], data.size());
    m_upload_data.appendData(d);
}