| // Copyright 2017 Google Inc. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "cobalt/websocket/buffered_amount_tracker.h" |
| |
| #include <algorithm> |
| |
| #include "base/logging.h" |
| |
| namespace cobalt { |
| namespace websocket { |
| |
| std::size_t BufferedAmountTracker::Pop(const std::size_t number_bytes_to_pop) { |
| std::size_t size_left_pop = number_bytes_to_pop; |
| std::size_t payload_amount = 0; |
| while (!entries_.empty() && (size_left_pop > 0)) { |
| Entry& entry(entries_[0]); |
| |
| std::size_t potential_payload_delta = 0; |
| if (entry.message_size_ > size_left_pop) { |
| potential_payload_delta = size_left_pop; |
| entry.message_size_ -= size_left_pop; |
| } else { // entry.message_size <= size_left |
| potential_payload_delta += entry.message_size_; |
| entries_.pop_front(); |
| } |
| |
| if (entry.is_user_payload_) { |
| payload_amount += potential_payload_delta; |
| } |
| |
| size_left_pop -= potential_payload_delta; |
| } |
| |
| // std::min prevents an underflow due to a bug. |
| DCHECK_LE(payload_amount, total_payload_inflight_); |
| |
| total_payload_inflight_ -= std::min(total_payload_inflight_, payload_amount); |
| |
| // Sort of an overflow check... |
| DCHECK_LE(size_left_pop, number_bytes_to_pop); |
| |
| return payload_amount; |
| } |
| |
| } // namespace websocket |
| } // namespace cobalt |