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28 #ifndef TALK_BASE_RATELIMITER_H_
29 #define TALK_BASE_RATELIMITER_H_
32 #include "talk/base/basictypes.h"
36 // Limits the rate of use to a certain maximum quantity per period of
37 // time. Use, for example, for simple bandwidth throttling.
39 // It's implemented like a diet plan: You have so many calories per
40 // day. If you hit the limit, you can't eat any more until the next
44 // For example, 100kb per second.
45 RateLimiter(size_t max, double period)
46 : max_per_period_(max),
47 period_length_(period),
52 virtual ~RateLimiter() {}
54 // Returns true if if the desired quantity is available in the
55 // current period (< (max - used)). Once the given time passes the
56 // end of the period, used is set to zero and more use is available.
57 bool CanUse(size_t desired, double time);
58 // Increment the quantity used this period. If past the end of a
59 // period, a new period is started.
60 void Use(size_t used, double time);
62 size_t used_in_period() const {
63 return used_in_period_;
66 size_t max_per_period() const {
67 return max_per_period_;
71 size_t max_per_period_;
72 double period_length_;
73 size_t used_in_period_;
78 } // namespace talk_base
80 #endif // TALK_BASE_RATELIMITER_H_