src/basic/ratelimit.c

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