/*

 * Copyright (c) 2021 Yubico AB. All rights reserved.

 * Use of this source code is governed by a BSD-style

 * license that can be found in the LICENSE file.

 * SPDX-License-Identifier: BSD-2-Clause

 */

#include <errno.h>

#include "fido.h"

static int

timespec_to_ms(const struct timespec *ts)

{

        int64_t x, y;

        if (ts->tv_sec < 0 || ts->tv_nsec < 0 ||

            ts->tv_nsec >= 1000000000LL)

                return -1;

        if ((uint64_t)ts->tv_sec >= INT64_MAX / 1000LL)

                return -1;

        x = ts->tv_sec * 1000LL;

        y = ts->tv_nsec / 1000000LL;

        if (INT64_MAX - x < y || x + y > INT_MAX)

                return -1;

        return (int)(x + y);

}

int

fido_time_now(struct timespec *ts_now)

{

        if (clock_gettime(CLOCK_MONOTONIC, ts_now) != 0) {

                fido_log_error(errno, "%s: clock_gettime", __func__);

                return -1;

        }

        return 0;

}

int

fido_time_delta(const struct timespec *ts_start, int *ms_remain)

{

        struct timespec ts_end, ts_delta;

        int ms;

        if (*ms_remain < 0)

                return 0;

        if (clock_gettime(CLOCK_MONOTONIC, &ts_end) != 0) {

                fido_log_error(errno, "%s: clock_gettime", __func__);

                return -1;

        }

        if (timespeccmp(&ts_end, ts_start, <)) {

                fido_log_debug("%s: timespeccmp", __func__);

                return -1;

        }

        timespecsub(&ts_end, ts_start, &ts_delta);

        if ((ms = timespec_to_ms(&ts_delta)) < 0) {

                fido_log_debug("%s: timespec_to_ms", __func__);

                return -1;

        }

        if (ms > *ms_remain)

                ms = *ms_remain;

        *ms_remain -= ms;

        return 0;

}