gpssim.cpp

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/****************************************************************************
 *
 *   Copyright (c) 2015 Roman Bapst. All rights reserved.
 *
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 * modification, are permitted provided that the following conditions
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 * 1. Redistributions of source code must retain the above copyright
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/**
 * @file gpssim.cpp
 * Simulated GPS driver
 */

#include <sys/types.h>
#include <px4_platform_common/defines.h>
#include <px4_platform_common/getopt.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdbool.h>
#include <stdlib.h>
#include <semaphore.h>
#include <string.h>
#include <fcntl.h>
#include <poll.h>
#include <errno.h>
#include <stdio.h>
#include <random>
#include <math.h>
#include <unistd.h>
#include <fcntl.h>
#include <px4_platform_common/px4_config.h>
#include <px4_platform_common/tasks.h>
#include <drivers/drv_hrt.h>
#include <drivers/device/device.h>
#include <uORB/uORB.h>
#include <uORB/topics/vehicle_gps_position.h>
#include <uORB/topics/satellite_info.h>

#include <simulator/simulator.h>

#include "DevMgr.hpp"
#include "VirtDevObj.hpp"

using namespace DriverFramework;

#define GPS_DRIVER_MODE_UBX_SIM
#define GPSSIM_DEVICE_PATH "/dev/gpssim"

#define TIMEOUT_100MS 100000
#define RATE_MEASUREMENT_PERIOD 5000000

/* class for dynamic allocation of satellite info data */
class GPS_Sat_Info
{
public:
    struct satellite_info_s     _data;
};


class GPSSIM : public VirtDevObj
{
public:
    GPSSIM(bool fake_gps, bool enable_sat_info,
           int fix_type, int num_sat, int noise_multiplier);
    ~GPSSIM() override;

    int     init() override;

    int     devIOCTL(unsigned long cmd, unsigned long arg) override;

    void set(int fix_type, int num_sat, int noise_multiplier);

    /**
     * Diagnostics - print some basic information about the driver.
     */
    void                print_info();

protected:
    void        _measure() override {}

private:

    bool                _task_should_exit;              ///< flag to make the main worker task exit
    volatile int            _task;                      ///< worker task
    GPS_Sat_Info            *_Sat_Info;                 ///< instance of GPS sat info data object
    struct vehicle_gps_position_s   _report_gps_pos;                ///< uORB topic for gps position
    orb_advert_t            _report_gps_pos_pub;                ///< uORB pub for gps position
    struct satellite_info_s     *_p_report_sat_info;                ///< pointer to uORB topic for satellite info
    orb_advert_t            _report_sat_info_pub;               ///< uORB pub for satellite info
    SyncObj             _sync;
    int _fix_type;
    int _num_sat;
    int _noise_multiplier;

    std::default_random_engine _gen;

    /**
     * Try to configure the GPS, handle outgoing communication to the GPS
     */
    void                config();

    /**
     * Trampoline to the worker task
     */
    static int          task_main_trampoline(int argc, char *argv[]);


    /**
     * Worker task: main GPS thread that configures the GPS and parses incoming data, always running
     */
    void                task_main();

    /**
     * Set the baudrate of the UART to the GPS
     */
    int             set_baudrate(unsigned baud);

    /**
     * Send a reset command to the GPS
     */
    void                cmd_reset();

    int                 receive(int timeout);
};


/*
 * Driver 'main' command.
 */
extern "C" __EXPORT int gpssim_main(int argc, char *argv[]);

namespace
{

GPSSIM  *g_dev = nullptr;

}


GPSSIM::GPSSIM(bool fake_gps, bool enable_sat_info,
           int fix_type, int num_sat, int noise_multiplier) :
    VirtDevObj("gps", GPSSIM_DEVICE_PATH, nullptr, 1e6 / 10),
    _task_should_exit(false),
    _Sat_Info(nullptr),
    _report_gps_pos{},
    _report_gps_pos_pub(nullptr),
    _p_report_sat_info(nullptr),
    _report_sat_info_pub(nullptr),
    _fix_type(fix_type),
    _num_sat(num_sat),
    _noise_multiplier(noise_multiplier)
{
    /* we need this potentially before it could be set in task_main */
    g_dev = this;
    _report_gps_pos.heading = NAN;
    _report_gps_pos.heading_offset = NAN;

    /* create satellite info data object if requested */
    if (enable_sat_info) {
        _Sat_Info = new (GPS_Sat_Info);
        _p_report_sat_info = &_Sat_Info->_data;
        memset(_p_report_sat_info, 0, sizeof(*_p_report_sat_info));
    }
}

GPSSIM::~GPSSIM()
{
    delete _Sat_Info;

    /* tell the task we want it to go away */
    _task_should_exit = true;

    /* spin waiting for the task to stop */
    for (unsigned i = 0; (i < 10) && (_task != -1); i++) {
        /* give it another 100ms */
        px4_usleep(100000);
    }

    /* well, kill it anyway, though this will probably crash */
    if (_task != -1) {
        px4_task_delete(_task);
    }

    g_dev = nullptr;
}

int
GPSSIM::init()
{
    int ret = PX4_ERROR;

    /* do regular cdev init */
    if (VirtDevObj::init() != OK) {
        goto out;
    }

    /* start the GPS driver worker task */
    _task = px4_task_spawn_cmd("gpssim", SCHED_DEFAULT,
                   SCHED_PRIORITY_DEFAULT, 1500, (px4_main_t)&GPSSIM::task_main_trampoline, nullptr);

    if (_task < 0) {
        PX4_ERR("task start failed: %d", errno);
        return -errno;
    }

    ret = OK;
out:
    return ret;
}

int
GPSSIM::devIOCTL(unsigned long cmd, unsigned long arg)
{
    _sync.lock();

    int ret = OK;

    switch (cmd) {
    case SENSORIOCRESET:
        cmd_reset();
        break;

    default:
        /* give it to parent if no one wants it */
        ret = VirtDevObj::devIOCTL(cmd, arg);
        break;
    }

    _sync.unlock();

    return ret;
}

int
GPSSIM::task_main_trampoline(int argc, char *argv[])
{
    g_dev->task_main();
    return 0;
}

int
GPSSIM::receive(int timeout)
{
    Simulator *sim = Simulator::getInstance();
    simulator::RawGPSData gps;

    static uint64_t timestamp_last = 0;

    if (sim->getGPSSample((uint8_t *)&gps, sizeof(gps)) &&
        (gps.timestamp != timestamp_last || timestamp_last == 0)) {
        _report_gps_pos.timestamp = hrt_absolute_time();
        _report_gps_pos.lat = gps.lat;
        _report_gps_pos.lon = gps.lon;
        _report_gps_pos.alt = gps.alt;
        _report_gps_pos.eph = (float)gps.eph * 1e-2f;
        _report_gps_pos.epv = (float)gps.epv * 1e-2f;
        _report_gps_pos.vel_m_s = (float)(gps.vel) / 100.0f;
        _report_gps_pos.vel_n_m_s = (float)(gps.vn) / 100.0f;
        _report_gps_pos.vel_e_m_s = (float)(gps.ve) / 100.0f;
        _report_gps_pos.vel_d_m_s = (float)(gps.vd) / 100.0f;
        _report_gps_pos.cog_rad = (float)(gps.cog) * 3.1415f / (100.0f * 180.0f);
        _report_gps_pos.fix_type = gps.fix_type;
        _report_gps_pos.satellites_used = gps.satellites_visible;
        _report_gps_pos.s_variance_m_s = 0.25f;

        timestamp_last = gps.timestamp;

        // check for data set by the user
        _report_gps_pos.fix_type = (_fix_type < 0) ? _report_gps_pos.fix_type : _fix_type;
        _report_gps_pos.satellites_used = (_num_sat < 0) ? _report_gps_pos.satellites_used : _num_sat;
        // use normal distribution for noise
        std::normal_distribution<float> normal_distribution(0.0f, 1.0f);
        _report_gps_pos.lat += (int32_t)(_noise_multiplier * normal_distribution(_gen));
        _report_gps_pos.lon += (int32_t)(_noise_multiplier * normal_distribution(_gen));

        return 1;

    } else {

        px4_usleep(timeout);
        return 0;
    }
}

void
GPSSIM::task_main()
{
    /* loop handling received serial bytes and also configuring in between */
    while (!_task_should_exit) {

        int recv_ret = receive(TIMEOUT_100MS);

        if (recv_ret > 0) {

            /* opportunistic publishing - else invalid data would end up on the bus */
            if (_report_gps_pos_pub != nullptr) {
                orb_publish(ORB_ID(vehicle_gps_position), _report_gps_pos_pub, &_report_gps_pos);

            } else {
                _report_gps_pos_pub = orb_advertise(ORB_ID(vehicle_gps_position), &_report_gps_pos);
            }

            if (_p_report_sat_info) {
                if (_report_sat_info_pub != nullptr) {
                    orb_publish(ORB_ID(satellite_info), _report_sat_info_pub, _p_report_sat_info);

                } else {
                    _report_sat_info_pub = orb_advertise(ORB_ID(satellite_info), _p_report_sat_info);
                }
            }
        }
    }

    if (_report_gps_pos_pub) {
        orb_unadvertise(_report_gps_pos_pub);
    }

    if (_report_sat_info_pub) {
        orb_unadvertise(_report_sat_info_pub);
    }

    PX4_INFO("exiting");

    /* tell the dtor that we are exiting */
    _task = -1;
}



void
GPSSIM::cmd_reset()
{
}

void
GPSSIM::print_info()
{
    //GPS Mode
    PX4_INFO("protocol: SIM");

    PX4_INFO("sat info: %s, noise: %d, jamming detected: %s",
         (_p_report_sat_info != nullptr) ? "enabled" : "disabled",
         _report_gps_pos.noise_per_ms,
         _report_gps_pos.jamming_indicator == 255 ? "YES" : "NO");

    if (_report_gps_pos.timestamp != 0) {
        print_message(_report_gps_pos);
    }

    px4_usleep(100000);
}

void
GPSSIM::set(int fix_type, int num_sat, int noise_multiplier)
{
    _fix_type = fix_type;
    _num_sat = num_sat;
    _noise_multiplier = noise_multiplier;
    PX4_INFO("Parameters set");
}

/**
 * Local functions in support of the shell command.
 */
namespace gpssim
{

GPSSIM  *g_dev = nullptr;

void    start(bool fake_gps, bool enable_sat_info,
          int fix_type, int num_sat, int noise_multiplier);
void    stop();
void    test();
void    reset();
void    info();
void    usage(const char *reason);

/**
 * Start the driver.
 */
void
start(bool fake_gps, bool enable_sat_info, int fix_type, int num_sat, int noise_multiplier)
{
    DevHandle h;

    /* create the driver */
    g_dev = new GPSSIM(fake_gps, enable_sat_info, fix_type, num_sat, noise_multiplier);

    if (g_dev == nullptr) {
        goto fail;
    }

    if (OK != g_dev->init()) {
        goto fail;
    }

    /* set the poll rate to default, starts automatic data collection */
    DevMgr::getHandle(GPSSIM_DEVICE_PATH, h);

    if (!h.isValid()) {
        PX4_ERR("getHandle failed: %s", GPSSIM_DEVICE_PATH);
        goto fail;
    }

    return;

fail:

    if (g_dev != nullptr) {
        delete g_dev;
        g_dev = nullptr;
    }

    PX4_ERR("start failed");
}

/**
 * Stop the driver.
 */
void
stop()
{
    delete g_dev;
    g_dev = nullptr;
}

/**
 * Perform some basic functional tests on the driver;
 * make sure we can collect data from the sensor in polled
 * and automatic modes.
 */
void
test()
{
    PX4_INFO("PASS");
}

/**
 * Reset the driver.
 */
void
reset()
{
    DevHandle h;
    DevMgr::getHandle(GPSSIM_DEVICE_PATH, h);

    if (!h.isValid()) {
        PX4_ERR("failed ");
    }

    if (h.ioctl(SENSORIOCRESET, 0) < 0) {
        PX4_ERR("reset failed");
    }
}

/**
 * Print the status of the driver.
 */
void
info()
{
    if (g_dev == nullptr) {
        PX4_ERR("gpssim not running");
        return;
    }

    g_dev->print_info();
}

void
usage(const char *reason)
{
    if (reason) {
        PX4_WARN("%s", reason);
    }

    PX4_INFO("usage:");
    PX4_INFO("gpssim {start|stop|test|reset|status|set}");
    PX4_INFO("       [-d /dev/ttyS0-n][-f (for enabling fake)][-s (to enable sat info)]");
    PX4_INFO("       [-t # (for setting fix_type)][-n # (for setting # satellites)][-m # (for setting noise multiplier [scalar] for normal distribution)]");
}

} // namespace



int
gpssim_main(int argc, char *argv[])
{
    // set to default
    bool fake_gps = false;
    bool enable_sat_info = false;
    int fix_type = -1;
    int num_sat = -1;
    int noise_multiplier = 0;

    // check for optional arguments
    int ch;
    int myoptind = 1;
    const char *myoptarg = nullptr;

    while ((ch = px4_getopt(argc, argv, "fst:n:m:", &myoptind, &myoptarg)) != EOF) {
        switch (ch) {
        case 'f':
            fake_gps = true;
            PX4_INFO("Using fake GPS");
            break;

        case 's':
            enable_sat_info = true;
            PX4_INFO("Satellite info enabled");
            break;

        case 't':
            fix_type = atoi(myoptarg);
            PX4_INFO("Setting fix_type to %d", fix_type);
            break;

        case 'n':
            num_sat = atoi(myoptarg);
            PX4_INFO("Setting number of satellites to %d", num_sat);
            break;

        case 'm':
            noise_multiplier = atoi(myoptarg);
            PX4_INFO("Setting noise multiplier to %d", noise_multiplier);
            break;

        default:
            PX4_WARN("Unknown option!");
        }
    }

    if (myoptind >= argc) {
        gpssim::usage("not enough arguments supplied");
        return 1;
    }

    /*
     * Start/load the driver.
     */
    if (!strcmp(argv[myoptind], "start")) {
        if (g_dev != nullptr) {
            PX4_WARN("already started");
            return 0;
        }

        gpssim::start(fake_gps, enable_sat_info, fix_type, num_sat, noise_multiplier);
        return 0;
    }

    /* The following need gpssim running. */
    if (g_dev == nullptr) {
        PX4_WARN("not running");
        return 1;
    }

    if (!strcmp(argv[myoptind], "stop")) {
        gpssim::stop();
    }

    /*
     * Test the driver/device.
     */
    if (!strcmp(argv[myoptind], "test")) {
        gpssim::test();
    }

    /*
     * Reset the driver.
     */
    if (!strcmp(argv[myoptind], "reset")) {
        gpssim::reset();
    }

    /*
     * Print driver status.
     */
    if (!strcmp(argv[myoptind], "status")) {
        gpssim::info();
    }

    /*
     * Set parameters
     */
    if (!strcmp(argv[myoptind], "set")) {
        g_dev->set(fix_type, num_sat, noise_multiplier);
    }

    return 0;
}