#include "log.h"

void log_test()
{
	SLOG_E("test");
	SLOG_W("test");
	SLOG_I("test");	
	SLOG_D("test");
}

log.c

#include <stdio.h>
#include <stdarg.h>

#include "stm32f4xx_hal.h"
#include "usart.h"

int _kprintf(const char *fmt, ...)
{
    va_list args;
    int length;
    static char log_buf[128];

    va_start(args, fmt);
    length = vsnprintf(log_buf, sizeof(log_buf), fmt, args);
    va_end(args);

    if (length >= sizeof(log_buf))
    {
        length = sizeof(log_buf) - 1;
    }

    if (HAL_UART_Transmit(&huart4, (uint8_t *)log_buf, length, 1000) != HAL_OK)
    {
        return -1;
    }

    return length;
}

log.h

#ifndef LOG_H__
#define LOG_H__

/* DEBUG level */
#define DBG_ERROR 0
#define DBG_WARNING 1
#define DBG_INFO 2
#define DBG_LOG 3

#ifdef DBG_TAG
#ifndef DBG_SECTION_NAME
#define DBG_SECTION_NAME DBG_TAG
#endif
#else
/* compatible with old version */
#ifndef DBG_SECTION_NAME
#define DBG_SECTION_NAME "DBG"
#endif
#endif /* DBG_TAG */

#ifdef DBG_LVL
#ifndef DBG_LEVEL
#define DBG_LEVEL DBG_LVL
#endif
#else
/* compatible with old version */
#ifndef DBG_LEVEL
#define DBG_LEVEL DBG_LOG
#endif
#endif /* DBG_LVL */

/*
 * The color for terminal (foreground)
 * BLACK    30
 * RED      31
 * GREEN    32
 * YELLOW   33
 * BLUE     34
 * PURPLE   35
 * CYAN     36
 * WHITE    37
 */
#define _DBG_COLOR(n) _kprintf("\033[" #n "m")
#define _DBG_LOG_HDR(lvl_name, color_n) \
    _kprintf("\033[" #color_n "m[" lvl_name "/" DBG_SECTION_NAME "] ")
#define _DBG_LOG_X_END \
    _kprintf("\033[0m\r\n")

/*
 * static debug routine
 * NOTE: This is a NOT RECOMMENDED API. Please using LOG_X API.
 *       It will be DISCARDED later. Because it will take up more resources.
 */
#define dbg_log(level, fmt, ...)      \
    if ((level) <= DBG_LEVEL)         \
    {                                 \
        switch (level)                \
        {                             \
        case DBG_ERROR:               \
            _DBG_LOG_HDR("E", 31);    \
            break;                    \
        case DBG_WARNING:             \
            _DBG_LOG_HDR("W", 33);    \
            break;                    \
        case DBG_INFO:                \
            _DBG_LOG_HDR("I", 32);    \
            break;                    \
        case DBG_LOG:                 \
            _DBG_LOG_HDR("D", 0);     \
            break;                    \
        default:                      \
            break;                    \
        }                             \
        _kprintf(fmt, ##__VA_ARGS__); \
        _DBG_COLOR(0);                \
    }

#define dbg_log_line(lvl, color_n, fmt, ...) \
    do                                       \
    {                                        \
        _DBG_LOG_HDR(lvl, color_n);          \
        _kprintf(fmt, ##__VA_ARGS__);        \
        _DBG_LOG_X_END;                      \
    } while (0)

#define dbg_raw(...) _kprintf(__VA_ARGS__);

#if (DBG_LEVEL >= DBG_LOG)
#define LOG_D(fmt, ...) dbg_log_line("D", 0, fmt, ##__VA_ARGS__)
#else
#define LOG_D(...)
#endif

#if (DBG_LEVEL >= DBG_INFO)
#define LOG_I(fmt, ...) dbg_log_line("I", 32, fmt, ##__VA_ARGS__)
#else
#define LOG_I(...)
#endif

#if (DBG_LEVEL >= DBG_WARNING)
#define LOG_W(fmt, ...) dbg_log_line("W", 33, fmt, ##__VA_ARGS__)
#else
#define LOG_W(...)
#endif

#if (DBG_LEVEL >= DBG_ERROR)
#define LOG_E(fmt, ...) dbg_log_line("E", 31, fmt, ##__VA_ARGS__)
#else
#define LOG_E(...)
#endif

#define LOG_RAW(...) dbg_raw(__VA_ARGS__)
#define LOG_HEX(name, width, buf, size)

#define SLOG_E(format, ...) LOG_E("%d:%s(): " format, __LINE__, __FUNCTION__, ##__VA_ARGS__)
#define SLOG_W(format, ...) LOG_W("%d:%s(): " format, __LINE__, __FUNCTION__, ##__VA_ARGS__)
#define SLOG_D(format, ...) LOG_D("%d:%s(): " format, __LINE__, __FUNCTION__, ##__VA_ARGS__)
#define SLOG_I(format, ...) LOG_I("%d:%s(): " format, __LINE__, __FUNCTION__, ##__VA_ARGS__)

int _kprintf(const char *fmt, ...);

#endif