linux c日志系统设计

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

#define LOG_LEVEL_DEBUG 0
#define LOG_LEVEL_INFO 1
#define LOG_LEVEL_WARNING 2
#define LOG_LEVEL_ERROR 3
#define LOG_LEVEL_CRITICAL 4

int log_level = LOG_LEVEL_INFO;

void log_message(int level, const char *format, ...) {
    if (level < log_level) return;

    time_t now = time(NULL);
    char *time_str = ctime(&now);
    time_str[strlen(time_str) - 1] = '\0'; // Remove newline character

    const char *level_str;
    switch (level) {
        case LOG_LEVEL_DEBUG: level_str = "DEBUG"; break;
        case LOG_LEVEL_INFO: level_str = "INFO"; break;
        case LOG_LEVEL_WARNING: level_str = "WARNING"; break;
        case LOG_LEVEL_ERROR: level_str = "ERROR"; break;
        case LOG_LEVEL_CRITICAL: level_str = "CRITICAL"; break;
        default: level_str = "UNKNOWN"; break;
    }

    fprintf(stderr, "[%s] [%s] ", time_str, level_str);

    va_list args;
    va_start(args, format);
    vfprintf(stderr, format, args);
    va_end(args);

    fprintf(stderr, "\n");
}

int main() {
    log_message(LOG_LEVEL_DEBUG, "This is a debug message.");
    log_message(LOG_LEVEL_INFO, "This is an info message.");
    log_message(LOG_LEVEL_WARNING, "This is a warning message.");
    log_message(LOG_LEVEL_ERROR, "This is an error message.");
    log_message(LOG_LEVEL_CRITICAL, "This is a critical message.");
    return 0;
}

/path/to/logfile.log {
    daily
    missingok
    rotate 7
    compress
    delaycompress
    notifempty
    create 0640 root root
}