henrike@webrtc.org | 47be73b | 2014-05-13 18:00:26 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2012 The WebRTC Project Authors. All rights reserved. |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license |
| 5 | * that can be found in the LICENSE file in the root of the source |
| 6 | * tree. An additional intellectual property rights grant can be found |
| 7 | * in the file PATENTS. All contributing project authors may |
| 8 | * be found in the AUTHORS file in the root of the source tree. |
| 9 | */ |
| 10 | |
Henrik Kjellander | fb3e1b6 | 2017-06-29 06:03:04 | [diff] [blame] | 11 | #ifndef WEBRTC_RTC_BASE_RATELIMITER_H_ |
| 12 | #define WEBRTC_RTC_BASE_RATELIMITER_H_ |
henrike@webrtc.org | 47be73b | 2014-05-13 18:00:26 | [diff] [blame] | 13 | |
Henrik Kjellander | 88b2dd4 | 2017-06-29 05:52:50 | [diff] [blame] | 14 | #include <stddef.h> |
henrike@webrtc.org | 47be73b | 2014-05-13 18:00:26 | [diff] [blame] | 15 | |
Henrik Kjellander | 88b2dd4 | 2017-06-29 05:52:50 | [diff] [blame] | 16 | namespace rtc { |
| 17 | |
| 18 | // Limits the rate of use to a certain maximum quantity per period of |
| 19 | // time. Use, for example, for simple bandwidth throttling. |
| 20 | // |
| 21 | // It's implemented like a diet plan: You have so many calories per |
| 22 | // day. If you hit the limit, you can't eat any more until the next |
| 23 | // day. |
| 24 | class RateLimiter { |
| 25 | public: |
| 26 | // For example, 100kb per second. |
| 27 | RateLimiter(size_t max, double period) |
| 28 | : max_per_period_(max), |
| 29 | period_length_(period), |
| 30 | used_in_period_(0), |
| 31 | period_start_(0.0), |
| 32 | period_end_(period) { |
| 33 | } |
| 34 | virtual ~RateLimiter() {} |
| 35 | |
| 36 | // Returns true if if the desired quantity is available in the |
| 37 | // current period (< (max - used)). Once the given time passes the |
| 38 | // end of the period, used is set to zero and more use is available. |
| 39 | bool CanUse(size_t desired, double time); |
| 40 | // Increment the quantity used this period. If past the end of a |
| 41 | // period, a new period is started. |
| 42 | void Use(size_t used, double time); |
| 43 | |
| 44 | size_t used_in_period() const { |
| 45 | return used_in_period_; |
| 46 | } |
| 47 | |
| 48 | size_t max_per_period() const { |
| 49 | return max_per_period_; |
| 50 | } |
| 51 | |
| 52 | private: |
| 53 | size_t max_per_period_; |
| 54 | double period_length_; |
| 55 | size_t used_in_period_; |
| 56 | double period_start_; |
| 57 | double period_end_; |
| 58 | }; |
| 59 | |
| 60 | } // namespace rtc |
henrike@webrtc.org | 47be73b | 2014-05-13 18:00:26 | [diff] [blame] | 61 | |
Henrik Kjellander | fb3e1b6 | 2017-06-29 06:03:04 | [diff] [blame] | 62 | #endif // WEBRTC_RTC_BASE_RATELIMITER_H_ |