src/basic/ratelimit.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2010 Lennart Poettering
   6 ***/
   7
   8
   9 #include <sys/time.h>
  10
  11 #include "macro.h"
  12 #include "ratelimit.h"
  13
  14 /* Modelled after Linux' lib/ratelimit.c by Dave Young
  15  * <hidave.darkstar@gmail.com>, which is licensed GPLv2. */
  16
  17 bool ratelimit_test(RateLimit *r) {
  18         usec_t ts;
  19
  20         assert(r);
  21
  22         if (r->interval <= 0 || r->burst <= 0)
  23                 return true;
  24
  25         ts = now(CLOCK_MONOTONIC);
  26
  27         if (r->begin <= 0 ||
  28             r->begin + r->interval < ts) {
  29                 r->begin = ts;
  30
  31                 /* Reset counter */
  32                 r->num = 0;
  33                 goto good;
  34         }
  35
  36         if (r->num < r->burst)
  37                 goto good;
  38
  39         return false;
  40
  41 good:
  42         r->num++;
  43         return true;
  44 }