timeval.c

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/*
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */
 
/**
 * $Id: 784564df23e556b7a616cab60ea1e7a16e9c43f1 $
 *
 * @brief Platform independent time functions
 * @file util/timeval.c
 *
 * @copyright 2019 Arran Cudbard-Bell (a.cudbardb@freeradius.org)
 */
 
#include <freeradius-devel/util/strerror.h>
#include <freeradius-devel/util/time.h>
#include <freeradius-devel/util/timeval.h>
 
/** Subtract one timeval from another
 *
 * @param[out] out Where to write difference.
 * @param[in] end Time closest to the present.
 * @param[in] start Time furthest in the past.
 */
void fr_timeval_subtract(struct timeval *out, struct timeval const *end, struct timeval const *start)
{
        out->tv_sec = end->tv_sec - start->tv_sec;
        if (out->tv_sec > 0) {
                out->tv_sec--;
                out->tv_usec = USEC;
        } else {
                out->tv_usec = 0;
        }
        out->tv_usec += end->tv_usec;
        out->tv_usec -= start->tv_usec;
 
        if (out->tv_usec >= USEC) {
                out->tv_usec -= USEC;
                out->tv_sec++;
        }
}
 
/** Create timeval from a string
 *
 * @param[out] out Where to write timeval.
 * @param[in] in String to parse.
 * @return
 *      - 0 on success.
 *      - -1 on failure.
 */
int fr_timeval_from_str(struct timeval *out, char const *in)
{
        unsigned long   sec;
        char    *end;
        struct  timeval tv;
 
        sec = strtoul(in, &end, 10);
        if ((sec == ULONG_MAX) || (in == end)) {
        failed:
                fr_strerror_printf("Failed parsing \"%s\" as timeval", in);
                return -1;
        }
        tv.tv_sec = sec;
        tv.tv_usec = 0;
 
        if (*end && (*end != '.')) goto failed;
 
        if (*end == '.') {
                size_t len;
                char const *frac;
 
                len = strlen(end + 1);
 
                if (len > 6) {
                        fr_strerror_const("Too much precision for timeval");
                        return -1;
                }
 
                /*
                 *      If they write "0.1", that means
                 *      "10000" microseconds.
                 */
                frac = end + 1;
 
                sec = strtoul(frac, &end, 10);
                if ((sec == ULONG_MAX) || (frac == end)) {
                        fr_strerror_printf("Failed parsing fractional component \"%s\" of timeval", in);
                        return -1;
                }
                while (len < 6) {
                        sec *= 10;
                        len++;
                }
                tv.tv_usec = sec;
        }
        *out = tv;
        return 0;
}