| // Copyright 2017 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "extensions/browser/api/feedback_private/access_rate_limiter.h" |
| |
| namespace extensions { |
| |
| AccessRateLimiter::AccessRateLimiter(size_t max_num_accesses, |
| const base::TimeDelta& recharge_period, |
| const base::TickClock* tick_clock) |
| : max_num_accesses_(max_num_accesses), |
| recharge_period_(recharge_period), |
| counter_(recharge_period * max_num_accesses), |
| tick_clock_(tick_clock) {} |
| |
| AccessRateLimiter::~AccessRateLimiter() = default; |
| |
| bool AccessRateLimiter::AttemptAccess() { |
| // If recharge period is 0, access is unlimited. |
| if (recharge_period_.is_zero()) |
| return true; |
| |
| // First, attempt to recharge. |
| const base::TimeTicks now = tick_clock_->NowTicks(); |
| if (!last_access_time_.is_null()) |
| counter_ += now - last_access_time_; |
| last_access_time_ = now; |
| |
| if (counter_ > recharge_period_ * max_num_accesses_) |
| counter_ = recharge_period_ * max_num_accesses_; |
| |
| // Is an immediate access available? |
| if (counter_ < recharge_period_) |
| return false; |
| |
| counter_ -= recharge_period_; |
| return true; |
| } |
| |
| } // namespace extensions |
