1/* 2 * nghttp2 - HTTP/2 C Library 3 * 4 * Copyright (c) 2023 nghttp2 contributors 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining 7 * a copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sublicense, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be 15 * included in all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 24 */ 25#ifndef NGHTTP2_RATELIM_H 26#define NGHTTP2_RATELIM_H 27 28#ifdef HAVE_CONFIG_H 29# include <config.h> 30#endif /* HAVE_CONFIG_H */ 31 32#include <nghttp2/nghttp2.h> 33 34typedef struct nghttp2_ratelim { 35 /* burst is the maximum value of val. */ 36 uint64_t burst; 37 /* rate is the amount of value that is regenerated per 1 tstamp. */ 38 uint64_t rate; 39 /* val is the amount of value available to drain. */ 40 uint64_t val; 41 /* tstamp is the last timestamp in second resolution that is known 42 to this object. */ 43 uint64_t tstamp; 44} nghttp2_ratelim; 45 46/* nghttp2_ratelim_init initializes |rl| with the given parameters. */ 47void nghttp2_ratelim_init(nghttp2_ratelim *rl, uint64_t burst, uint64_t rate); 48 49/* nghttp2_ratelim_update updates rl->val with the current |tstamp| 50 given in second resolution. */ 51void nghttp2_ratelim_update(nghttp2_ratelim *rl, uint64_t tstamp); 52 53/* nghttp2_ratelim_drain drains |n| from rl->val. It returns 0 if it 54 succeeds, or -1. */ 55int nghttp2_ratelim_drain(nghttp2_ratelim *rl, uint64_t n); 56 57#endif /* NGHTTP2_RATELIM_H */ 58