//-----------------------------------------------------------------
// list_32.c:
//    経過時刻の出力設定
//-----------------------------------------------------------------
#include <stdio.h>
#include <time.h>

//-----------------------------------------------------------------
void   set_time(char* t_str);
char* work_time(char* e_time,char* s_time);
time_t get_time(char *tstr);
//-----------------------------------------------------------------

int main()
{
    char stime[256],etime[256];
    set_time(stime); // 開始時刻
    sleep(5);
    set_time(etime); // 終了時刻
    printf("    stime: %s\n",stime);
    printf("    etime: %s\n",etime);
    printf("経過時刻1: %s\n",work_time(etime,stime));
    //--------------------------------------------------
    // 文字列[YYYYMMDDHHMMSS]から経過時刻の計算
    //--------------------------------------------------
    sprintf(stime,"20041020173021");
    sprintf(etime,"20041125173131");
    printf("経過時刻2: %s\n",work_time(etime,stime));
    return 0;
}
//-----------------------------------------------------------------
// 時刻の設定
//-----------------------------------------------------------------
void set_time(char* t_str)
{
    time_t  t     = time(NULL);
    struct tm *tm = localtime(&t);
    strftime(t_str,sizeof(char)*256,"%Y%m%d%H%M%S",tm);
}
//-----------------------------------------------------------------
// 経過時刻の計算
//-----------------------------------------------------------------
char* work_time(char* e_time,char* s_time)
{
    char* retbuf=(char*)calloc(256,sizeof(char));
    int year,mon,day,hour,min,sec;
    time_t et = get_time(e_time);
    time_t st = get_time(s_time);
    time_t it = et - st;
    // 詳細時間計算
    sec  = it % 60; it /= 60;
    min  = it % 60; it /= 60;
    hour = it % 24;
    day  = it / 24;
    // 出力
    if(day) sprintf(retbuf,"%d日%02d時間%02d分%02d秒",day,hour,min,sec);
    else    sprintf(retbuf,"%02d時間%02d分%02d秒",hour,min,sec);
    return retbuf;
}
//-----------------------------------------------------------------
// get_time():
// "YYYYMMDDHHMMSS" 型テキストから time_t への変換
//-----------------------------------------------------------------
time_t get_time(char *tstr)
{
    char   buf[20];
    time_t cal_time;
    struct tm work_tm;
    if(strlen(tstr) != 14) return(-1);
    strncpy(buf, tstr, 4);
    buf[4] = '\0';
    work_tm.tm_year = atoi(buf) - 1900;
    strncpy(buf,tstr+4,2);
    buf[2] = '\0';
    work_tm.tm_mon = atoi(buf) - 1;
    strncpy(buf, tstr+4+2, 2);
    work_tm.tm_mday = atoi(buf);
    strncpy(buf, tstr+4+2+2, 2);
    work_tm.tm_hour = atoi(buf);
    strncpy(buf, tstr+4+2+2+2, 2);
    work_tm.tm_min = atoi(buf);
    strncpy(buf, tstr+4+2+2+2+2, 2);
    work_tm.tm_sec = atoi(buf);
    work_tm.tm_isdst = -1;
    if((cal_time=mktime(&work_tm)) == -1){
        return(-1);
    }
    return(cal_time);
}