gecko-dev/media/mtransport/simpletokenbucket.h
2013-10-25 15:15:59 -07:00

55 lines
1.5 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
/* Original author: bcampen@mozilla.com */
/*
* This file defines a dirt-simple token bucket class.
*/
#ifndef simpletokenbucket_h__
#define simpletokenbucket_h__
#include <stdint.h>
#include "prinrval.h"
#include "m_cpp_utils.h"
namespace mozilla {
class SimpleTokenBucket {
public:
/*
* Create a SimpleTokenBucket with a given maximum size and
* token replenishment rate.
* (eg; if you want a maximum rate of 5 per second over a 7 second
* period, call SimpleTokenBucket b(5*7, 5);)
*/
SimpleTokenBucket(size_t bucket_size, size_t tokens_per_second);
/*
* Attempt to acquire a number of tokens. If successful, returns
* |num_tokens|, otherwise returns the number of tokens currently
* in the bucket.
* Note: To get the number of tokens in the bucket, pass something
* like UINT32_MAX.
*/
size_t getTokens(size_t num_tokens);
protected: // Allow testing to touch these.
uint64_t max_tokens_;
uint64_t num_tokens_;
size_t tokens_per_second_;
PRIntervalTime last_time_tokens_added_;
DISALLOW_COPY_ASSIGN(SimpleTokenBucket);
};
} // namespace mozilla
#endif // simpletokenbucket_h__