Simple and macrofied logging | C++

macrologger.hpp

/**
 * @file macrologger.hpp
 *
 * @brief Quick and simple logging for C++ projects
 *
 * @author David Rodrigues (primary author)
 * @author Ashwin A Nayar
 *
 * Add compile flag -DLOG_LEVEL=<value> to set log level
 *
 * Log Level  |  Value
 * ===================
 * No logs       0
 * Error         1
 * Warning       2
 * Info          3
 * Debug         4 (default)
 */

////////////////////////////////////////////////////////////////////////////////////

/*
 * Copyright (c) 2012 David Rodrigues
 * Copyright (c) 2021 Ashwin A Nayar
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

////////////////////////////////////////////////////////////////////////////////////

#ifndef GISTS_MACROLOGGER_HPP
#define GISTS_MACROLOGGER_HPP

#include <cstring>
#include <ctime>

//! Auxiliary functions
static inline char *timenow();

#define SRC_FILE strrchr(__FILE__, '/') ? strrchr(__FILE__, '/') + 1 : __FILE__

#define NO_LOGS     0x00
#define ERROR_LEVEL 0x01
#define WARN_LEVEL  0x02
#define INFO_LEVEL  0x03
#define DEBUG_LEVEL 0x04

#ifndef LOG_LEVEL
#define LOG_LEVEL DEBUG_LEVEL
#endif

#define PRINTFUNCTION(format, ...) fprintf(stderr, format, __VA_ARGS__)

#define LOG_FMT           "%s | %-5s | %-15s | %-12s:%-3d | "
#define LOG_ARGS(LOG_TAG) timenow(), LOG_TAG, SRC_FILE, __FUNCTION__, __LINE__

#define NEWLINE "\n"

#define ERROR_TAG "ERROR"
#define WARN_TAG  "WARN"
#define INFO_TAG  "INFO"
#define DEBUG_TAG "DEBUG"

#if LOG_LEVEL >= DEBUG_LEVEL
#define LOG_DEBUG(message, ...)                                                     \
    PRINTFUNCTION(LOG_FMT message NEWLINE, LOG_ARGS(DEBUG_TAG), ##__VA_ARGS__)
#else
#define LOG_DEBUG(message, ...)
#endif

#if LOG_LEVEL >= INFO_LEVEL
#define LOG_INFO(message, ...)                                                      \
    PRINTFUNCTION(LOG_FMT message NEWLINE, LOG_ARGS(INFO_TAG), ##__VA_ARGS__)
#else
#define LOG_INFO(message, ...)
#endif

#if LOG_LEVEL >= WARN_LEVEL
#define LOG_WARN(message, ...)                                                      \
    PRINTFUNCTION(LOG_FMT message NEWLINE, LOG_ARGS(WARN_TAG), ##__VA_ARGS__)
#else
#define LOG_WARN(message, ...)
#endif

#if LOG_LEVEL >= ERROR_LEVEL
#define LOG_ERROR(message, ...)                                                     \
    PRINTFUNCTION(LOG_FMT message NEWLINE, LOG_ARGS(ERROR_TAG), ##__VA_ARGS__)
#else
#define LOG_ERROR(message, ...)
#endif

#if LOG_LEVEL >= NO_LOGS
#define LOG_IF_ERROR(condition, message, ...)                                       \
    if (condition)                                                                  \
    PRINTFUNCTION(LOG_FMT message NEWLINE, LOG_ARGS(ERROR_TAG), __VA_ARGS__)
#else
#define LOG_IF_ERROR(condition, message, args...)
#endif

static inline char *timenow()
{
    static char buffer[64];
    time_t rawtime;
    struct tm *timeinfo;
    time(&rawtime);
    timeinfo = localtime(&rawtime);
    strftime(buffer, 64, "%Y-%m-%d %H:%M:%S", timeinfo);
    return buffer;
}

#endif // GISTS_MACROLOGGER_HPP