src/lib/time-util.c

/* Copyright (c) 2008-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "time-util.h"

#include <time.h>

#define STRFTIME_MAX_BUFSIZE (1024*64)

int timeval_cmp(const struct timeval *tv1, const struct timeval *tv2)
{
    if (tv1->tv_sec < tv2->tv_sec)
        return -1;
    if (tv1->tv_sec > tv2->tv_sec)
        return 1;
    if (tv1->tv_usec < tv2->tv_usec)
        return -1;
    if (tv1->tv_usec > tv2->tv_usec)
        return 1;
    return 0;
}

int timeval_cmp_margin(const struct timeval *tv1, const struct timeval *tv2,
    unsigned int usec_margin)
{
    unsigned long long usecs_diff;
    int sec_margin, ret;

    if (tv1->tv_sec < tv2->tv_sec) {
        sec_margin = ((int)usec_margin / 1000000) + 1;
        if ((tv2->tv_sec - tv1->tv_sec) > sec_margin)
            return -1;
        usecs_diff = (tv2->tv_sec - tv1->tv_sec) * 1000000ULL +
            (tv2->tv_usec - tv1->tv_usec);
        ret = -1;
    } else if (tv1->tv_sec > tv2->tv_sec) {
        sec_margin = ((int)usec_margin / 1000000) + 1;
        if ((tv1->tv_sec - tv2->tv_sec) > sec_margin)
            return 1;
        usecs_diff = (tv1->tv_sec - tv2->tv_sec) * 1000000ULL +
            (tv1->tv_usec - tv2->tv_usec);
        ret = 1;
    } else if (tv1->tv_usec < tv2->tv_usec) {
        usecs_diff = tv2->tv_usec - tv1->tv_usec;
        ret = -1;
    } else {
        usecs_diff = tv1->tv_usec - tv2->tv_usec;
        ret = 1;
    }
    return usecs_diff > usec_margin ? ret : 0;
}

int timeval_diff_msecs(const struct timeval *tv1, const struct timeval *tv2)
{
    return timeval_diff_usecs(tv1, tv2) / 1000;
}

long long timeval_diff_usecs(const struct timeval *tv1,
                 const struct timeval *tv2)
{
    time_t secs;
    int usecs;

    secs = tv1->tv_sec - tv2->tv_sec;
    usecs = tv1->tv_usec - tv2->tv_usec;
    if (usecs < 0) {
        secs--;
        usecs += 1000000;
    }
    return ((long long)secs * 1000000LL) + usecs;
}

time_t time_to_local_day_start(time_t t)
{
    const struct tm *day_tm;
    struct tm tm;
    time_t new_start_time;

    day_tm = localtime(&t);
    i_zero(&tm);
    tm.tm_year = day_tm->tm_year;
    tm.tm_mon = day_tm->tm_mon;
    tm.tm_mday = day_tm->tm_mday;
    tm.tm_isdst = -1;
    new_start_time = mktime(&tm);
    i_assert(new_start_time != (time_t)-1);
    return new_start_time;
}

static const char *strftime_real(const char *fmt, const struct tm *tm)
{
    size_t bufsize = strlen(fmt) + 32;
    char *buf = t_buffer_get(bufsize);
    size_t ret;

    while ((ret = strftime(buf, bufsize, fmt, tm)) == 0) {
        bufsize *= 2;
        i_assert(bufsize <= STRFTIME_MAX_BUFSIZE);
        buf = t_buffer_get(bufsize);
    }
    t_buffer_alloc(ret + 1);
    return buf;
}

const char *t_strftime(const char *fmt, const struct tm *tm)
{
    return strftime_real(fmt, tm);
}

const char *t_strflocaltime(const char *fmt, time_t t)
{
    return strftime_real(fmt, localtime(&t));
}

const char *t_strfgmtime(const char *fmt, time_t t)
{
    return strftime_real(fmt, gmtime(&t));
}