From 55944e5e40b1be2afc4855d8d2baf4b73d1876b5 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 10 Apr 2024 22:49:52 +0200 Subject: Adding upstream version 255.4. Signed-off-by: Daniel Baumann --- src/basic/ratelimit.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 src/basic/ratelimit.c (limited to 'src/basic/ratelimit.c') diff --git a/src/basic/ratelimit.c b/src/basic/ratelimit.c new file mode 100644 index 0000000..41ca070 --- /dev/null +++ b/src/basic/ratelimit.c @@ -0,0 +1,60 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include + +#include "macro.h" +#include "ratelimit.h" + +/* Modelled after Linux' lib/ratelimit.c by Dave Young + * , which is licensed GPLv2. */ + +bool ratelimit_below(RateLimit *r) { + usec_t ts; + + assert(r); + + if (!ratelimit_configured(r)) + return true; + + ts = now(CLOCK_MONOTONIC); + + if (r->begin <= 0 || + usec_sub_unsigned(ts, r->begin) > r->interval) { + r->begin = ts; /* Start a new time window */ + r->num = 1; /* Reset counter */ + return true; + } + + if (_unlikely_(r->num == UINT_MAX)) + return false; + + r->num++; + return r->num <= r->burst; +} + +unsigned ratelimit_num_dropped(RateLimit *r) { + assert(r); + + if (r->num == UINT_MAX) /* overflow, return as special case */ + return UINT_MAX; + + return LESS_BY(r->num, r->burst); +} + +usec_t ratelimit_end(const RateLimit *rl) { + assert(rl); + + if (rl->begin == 0) + return 0; + + return usec_add(rl->begin, rl->interval); +} + +usec_t ratelimit_left(const RateLimit *rl) { + assert(rl); + + if (rl->begin == 0) + return 0; + + return usec_sub_unsigned(ratelimit_end(rl), now(CLOCK_MONOTONIC)); +} -- cgit v1.2.3