instance_logger.h

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#ifndef _ISS_LOGGER_H_
#define _ISS_LOGGER_H_
 
#include "delegate.h"
#include "logging.h"
 
namespace util {
 
struct LoggerDelegate {
    using delegate_fn = void(logging::log_level, std::string const&, std::string const&, unsigned, char const*);
    util::delegate<delegate_fn> log;
    logging::log_level level;
};

template <typename CATEGORY> class InstanceLogger {
public:
    InstanceLogger() = default;
 
    ~InstanceLogger() = default;
 
    InstanceLogger(const InstanceLogger&) = delete;
 
    InstanceLogger& operator=(const InstanceLogger&) = delete;
 
    void set_log_level(logging::log_level l) {
        if(logger) {
            logger->level = l;
        } else {
            ::logging ::Log<::logging ::Output2FILE<CATEGORY>>::set_reporting_level(l);
        }
    }
    logging::log_level get_log_level() {
        if(logger) {
            return logger->level;
        } else {
            return ::logging ::Log<::logging ::Output2FILE<CATEGORY>>::get_reporting_level();
        }
    }
    void log(logging::log_level level, const std::string& message, unsigned line, char const* file) {
        if(logger) {
            logger->log(level, CATEGORY::name, message, line, file);
        } else {
            if(level <= _LOGGER(CATEGORY)::get_reporting_level() && _LOG_OUTPUT(CATEGORY)::stream())
                ::logging::Log<::logging::Output2FILE<CATEGORY>>().get(level, CATEGORY::name) << message;
        }
    }
 
    void set_logger(LoggerDelegate& logger) { this->logger = &logger; }
 
private:
    LoggerDelegate* logger;
};
} // namespace util
 
#define ILOG(LOGGER, LEVEL, MSG)                                                                                                           \
    if(LEVEL <= this->LOGGER.get_log_level()) {                                                                                            \
        this->LOGGER.log(LEVEL, MSG, __LINE__, __FILE__);                                                                                  \
    }
#endif // _ISS_LOGGER_H_