std::string ServiceContext::get_time_zone()

in sample_app/onvif_camera_mock/artifacts/onvif_srvd/src/ServiceContext.cpp [34:87]

• 32 lines of code
• 8 McCabe index (conditional complexity)

std::string ServiceContext::get_time_zone() const
{
    #define HH_FORMAT   std::setfill('0') << std::internal << std::setw(3) << std::showpos
    #define MM_FORMAT   ':' << std::setw(2) << std::noshowpos

    std::ostringstream res;
    char* TZ_env;
    const time_t  timestamp = time(NULL);
    struct tm    *now       = localtime(&timestamp);


    //global var timezone is not adjusted for daylight saving!
    //In GNU programs it is better to use tm_gmtoff, since it contains the correct
    //offset even when it is not the latest one.
    int hh = now->tm_gmtoff/3600;
    int mm = abs(now->tm_gmtoff%60);

    switch (tz_format)
    {
        case TZ_UTC_OFFSET:
            res << HH_FORMAT << hh << MM_FORMAT << mm;
            return res.str();


        case TZ_GMT_OFFSET:
            res << HH_FORMAT << -hh << MM_FORMAT << mm;
            return res.str();


        case TZ_UTC:
            res << "UTC" << HH_FORMAT << hh << MM_FORMAT << mm;
            return res.str();


        case TZ_GMT:
            res << "GMT" << HH_FORMAT << -hh << MM_FORMAT << mm;
            return res.str();


        case TZ_ENV:
            TZ_env = getenv("TZ");
            return (TZ_env ? TZ_env : "UTC+00");


        default:
            TZ_env = getenv("TZ_ONVIF");
            return (TZ_env ? TZ_env : "UTC+00");
    }

    //Note: for GMT sign
    //According to the definition, GMT and UTC mean the same thing!
    //But when offsets are specified, the sign of the GMT is inverted!
    //This feature is described here: https://en.wikipedia.org/wiki/Tz_database#Area
}