loss fo time

#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <stdio.h>
#include <errno.h>

int str2time(char *time,struct tm *outtime)
{
    struct tm tm;
    char temp[10] = {0};

    memset(&tm,0,sizeof(tm));

    if(time == NULL){
        return -1;
    }

    memset(temp,0,sizeof(temp));
    strncpy(temp,time,4);
    tm.tm_year = atoi(temp) - 1900;

    memset(temp,0,sizeof(temp));
    strncpy(temp,time+4,2);
    tm.tm_mon = atoi(temp) - 1;

    memset(temp,0,sizeof(temp));
    strncpy(temp,time+6,2);
    tm.tm_mday = atoi(temp);

    memset(temp,0,sizeof(temp));
    strncpy(temp,time+8,2);
    tm.tm_hour = atoi(temp);

    memset(temp,0,sizeof(temp));
    strncpy(temp,time+10,2);
    tm.tm_min = atoi(temp);

    memset(temp,0,sizeof(temp));
    strncpy(temp,time+12,2);
    tm.tm_sec = atoi(temp);

    tm.tm_isdst = -1;
    memcpy(outtime,&tm,sizeof(struct tm));

    return 0;
}

int lossFoTime(struct tm *current_tm,time_t loss_time)
{
    struct tm *temp_tm = NULL;
    time_t temp_time = (time_t)0;

    temp_time = mktime(current_tm);
    if(temp_time == (time_t)-1)
    {
        printf("errno is %d , errno message is %s\n",errno,strerror(errno));
        return -1;
    }

    temp_time += loss_time;

    temp_tm = localtime(&temp_time);
    if(temp_tm == NULL)
      {
        printf("errno is %d , errno message is %s\n",errno,strerror(errno));
        return -1;
    }

    memcpy(current_tm,temp_tm,sizeof(struct tm));
    return 0;
}

int main()
{
    char t[] = "20110228123245";
    char str_time[20] = { 0 };
    time_t loss_time = 1234;
    struct tm tm;

    memset(&tm,0,sizeof(tm));

    if(str2time(t,&tm) != 0)
    {
        printf("str2time wrong!\n");
        return -1;
    }

    if(lossFoTime(&tm,loss_time) != 0)
    {
        printf("lossFoTime wrong!\n");
        return -1;
    }

    strftime(str_time,sizeof(str_time),"%Y%m%d%H%M%S",&tm);

    printf("%s\n",str_time);

    return 0;
}