C 语言玩具版日志服务

log.h

#include 
#include 
#include 
#include 

typedef long long ll;

typedef struct log {
    ll timeStamp;
    char prefix[1024];
    char message[1024];
    void (*Println)(const char *message);
} Log;

char destination[1024];
char prefix[1024];

char* timeStamp() {
    static char len[20] = {0};

    time_t timep;
    time(&timep);

    struct tm *p = gmtime(&timep);
    snprintf(len, 20, "%d-%d-%d %d:%d:%d ", 1900 + p->tm_year, 1 + p->tm_mon, p->tm_mday, 8 + p->tm_hour, p->tm_min, p->tm_sec);
    return len;
}

void Println(const char _message[]) {
    char message[1024];

    char tfln[2] = "n";
    strcat(message, timeStamp());
    strcat(message, prefix);
    strcat(message, _message);
    strcat(message, tfln);

    FILE *fp = fopen(destination, "a+");
    fwrite(message, 1, strlen(message), fp);
    fclose(fp);
}

Log Log_Init(char _destination[1024], char _prefix[]) {
    strcpy(prefix, _prefix);
    strcpy(destination, _destination);

    static Log log;
    log.Println = Println;
    return log;
}

main.c

#include "log.h"

int main() {
    Log log = Log_Init("./data.log", "Logger ");
    log.Println("hello world");
}

运行结果