| // Copyright 2023 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef QUICHE_QUIC_MOQT_SUBSCRIBE_WINDOWS_H |
| #define QUICHE_QUIC_MOQT_SUBSCRIBE_WINDOWS_H |
| |
| #include <cstdint> |
| #include <list> |
| #include <optional> |
| |
| #include "quiche/quic/moqt/moqt_messages.h" |
| |
| namespace moqt { |
| |
| struct SubscribeWindow { |
| FullSequence start; |
| std::optional<FullSequence> end; |
| // Creates a half-open window. |
| SubscribeWindow(uint64_t start_group, uint64_t start_object) { |
| start = {start_group, start_object}; |
| end = std::nullopt; |
| } |
| // Creates a closed window. |
| SubscribeWindow(uint64_t start_group, uint64_t start_object, |
| uint64_t end_group, uint64_t end_object) { |
| start = {start_group, start_object}; |
| end = {end_group, end_object}; |
| } |
| bool InWindow(const FullSequence& seq) const { |
| if (seq < start) { |
| return false; |
| } |
| if (!end.has_value() || seq < *end) { |
| return true; |
| } |
| return false; |
| } |
| }; |
| |
| // Class to keep track of the sequence number blocks to which a peer is |
| // subscribed. |
| class MoqtSubscribeWindows { |
| public: |
| MoqtSubscribeWindows() {} |
| |
| bool SequenceIsSubscribed(uint64_t group, uint64_t object) const { |
| FullSequence seq(group, object); |
| for (auto it : windows) { |
| if (it.InWindow(seq)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| // |window| has already been converted into absolute sequence numbers. An |
| // optimization could consolidate overlapping subscribe windows. |
| void AddWindow(SubscribeWindow window) { windows.push_front(window); } |
| |
| bool IsEmpty() const { return windows.empty(); } |
| |
| private: |
| std::list<SubscribeWindow> windows; |
| }; |
| |
| } // namespace moqt |
| |
| #endif // QUICHE_QUIC_MOQT_SUBSCRIBE_WINDOWS_H |