src/shared/ratelimit.c

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

/***
  This file is part of systemd.

  Copyright 2010 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  systemd 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
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include <assert.h>

#include "ratelimit.h"
#include "log.h"

/* Modelled after Linux' lib/ratelimit.c by Dave Young
 * <hidave.darkstar@gmail.com>, which is licensed GPLv2. */

bool ratelimit_test(RateLimit *r) {
        usec_t ts;

        assert(r);

        if (r->interval <= 0 || r->burst <= 0)
                return true;

        ts = now(CLOCK_MONOTONIC);

        if (r->begin <= 0 ||
            r->begin + r->interval < ts) {
                r->begin = ts;

                /* Reset counter */
                r->num = 0;
                goto good;
        }

        if (r->num <= r->burst)
                goto good;

        return false;

good:
        r->num++;
        return true;
}