ratelimit.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   2
   3 #include <assert.h>
   4
   5 #include "ratelimit.h"
   6 #include "log.h"
   7
   8 /* Modelled after Linux' lib/ratelimit.c by Dave Young
   9  * <hidave.darkstar@gmail.com>, which is licensed GPLv2. */
  10
  11 bool ratelimit_test(RateLimit *r) {
  12         usec_t timestamp;
  13
  14         timestamp = now(CLOCK_MONOTONIC);
  15
  16         assert(r);
  17         assert(r->interval > 0);
  18         assert(r->burst > 0);
  19
  20         if (r->begin <= 0 ||
  21             r->begin + r->interval < timestamp) {
  22
  23                 if (r->n_missed > 0)
  24                         log_warning("%u events suppressed", r->n_missed);
  25
  26                 r->begin = timestamp;
  27
  28                 /* Reset counters */
  29                 r->n_printed = 0;
  30                 r->n_missed = 0;
  31                 goto good;
  32         }
  33
  34         if (r->n_printed <= r->burst)
  35                 goto good;
  36
  37         r->n_missed++;
  38         return false;
  39
  40 good:
  41         r->n_printed++;
  42         return true;
  43 }