关于打印数据的调试问题 about easylogger HOT 9 OPEN

/**
 * dump the hex format data to log
 *
 * @param name name for hex object, it will show on log header
 * @param width hex number for every line, such as: 16, 32
 * @param buf hex buffer
 * @param size buffer size
 */
void ulog_hexdump(const char *name, rt_size_t width, rt_uint8_t *buf, rt_size_t size)
{
#define __is_print(ch)       ((unsigned int)((ch) - ' ') < 127u - ' ')

    rt_size_t i, j;
    rt_size_t log_len = 0;
    char *log_buf = NULL, dump_string[8];
    int fmt_result;

    RT_ASSERT(ulog.init_ok);

    /* get log buffer */
    log_buf = get_log_buf();

    /* lock output */
    output_lock();

    for (i = 0, log_len = 0; i < size; i += width)
    {
        /* package header */
        fmt_result = rt_snprintf(log_buf, ULOG_LINE_BUF_SIZE, "D/HEX %s: %04X-%04X: ", name, i, i + width);
        /* calculate log length */
        if ((fmt_result > -1) && (fmt_result <= ULOG_LINE_BUF_SIZE))
        {
            log_len = fmt_result;
        }
        else
        {
            log_len = ULOG_LINE_BUF_SIZE;
        }
        /* dump hex */
        for (j = 0; j < width; j++)
        {
            if (i + j < size)
            {
                rt_snprintf(dump_string, sizeof(dump_string), "%02X ", buf[i + j]);
            }
            else
            {
                rt_strncpy(dump_string, "   ", sizeof(dump_string));
            }
            log_len += ulog_strcpy(log_len, log_buf + log_len, dump_string);
            if ((j + 1) % 8 == 0)
            {
                log_len += ulog_strcpy(log_len, log_buf + log_len, " ");
            }
        }
        log_len += ulog_strcpy(log_len, log_buf + log_len, "  ");
        /* dump char for hex */
        for (j = 0; j < width; j++)
        {
            if (i + j < size)
            {
                rt_snprintf(dump_string, sizeof(dump_string), "%c", __is_print(buf[i + j]) ? buf[i + j] : '.');
                log_len += ulog_strcpy(log_len, log_buf + log_len, dump_string);
            }
        }
        /* overflow check and reserve some space for newline sign */
        if (log_len + rt_strlen(ULOG_NEWLINE_SIGN) > ULOG_LINE_BUF_SIZE)
        {
            log_len = ULOG_LINE_BUF_SIZE - rt_strlen(ULOG_NEWLINE_SIGN);
        }
        /* package newline sign */
        log_len += ulog_strcpy(log_len, log_buf + log_len, ULOG_NEWLINE_SIGN);
        /* do log output */
        do_output(LOG_LVL_DBG, NULL, RT_TRUE, log_buf, log_len);
    }
    /* unlock output */
    output_unlock();
}