xref: /aosp_15_r20/external/webrtc/net/dcsctp/timer/fake_timeout.h (revision d9f758449e529ab9291ac668be2861e7a55c2422)
1 /*
2  *  Copyright (c) 2021 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 #ifndef NET_DCSCTP_TIMER_FAKE_TIMEOUT_H_
11 #define NET_DCSCTP_TIMER_FAKE_TIMEOUT_H_
12 
13 #include <cstdint>
14 #include <functional>
15 #include <limits>
16 #include <memory>
17 #include <utility>
18 #include <vector>
19 
20 #include "absl/types/optional.h"
21 #include "api/task_queue/task_queue_base.h"
22 #include "net/dcsctp/public/timeout.h"
23 #include "rtc_base/checks.h"
24 #include "rtc_base/containers/flat_set.h"
25 
26 namespace dcsctp {
27 
28 // A timeout used in tests.
29 class FakeTimeout : public Timeout {
30  public:
FakeTimeout(std::function<TimeMs ()> get_time,std::function<void (FakeTimeout *)> on_delete)31   FakeTimeout(std::function<TimeMs()> get_time,
32               std::function<void(FakeTimeout*)> on_delete)
33       : get_time_(std::move(get_time)), on_delete_(std::move(on_delete)) {}
34 
~FakeTimeout()35   ~FakeTimeout() override { on_delete_(this); }
36 
Start(DurationMs duration_ms,TimeoutID timeout_id)37   void Start(DurationMs duration_ms, TimeoutID timeout_id) override {
38     RTC_DCHECK(expiry_ == TimeMs::InfiniteFuture());
39     timeout_id_ = timeout_id;
40     expiry_ = get_time_() + duration_ms;
41   }
Stop()42   void Stop() override {
43     RTC_DCHECK(expiry_ != TimeMs::InfiniteFuture());
44     expiry_ = TimeMs::InfiniteFuture();
45   }
46 
EvaluateHasExpired(TimeMs now)47   bool EvaluateHasExpired(TimeMs now) {
48     if (now >= expiry_) {
49       expiry_ = TimeMs::InfiniteFuture();
50       return true;
51     }
52     return false;
53   }
54 
timeout_id()55   TimeoutID timeout_id() const { return timeout_id_; }
56 
57  private:
58   const std::function<TimeMs()> get_time_;
59   const std::function<void(FakeTimeout*)> on_delete_;
60 
61   TimeoutID timeout_id_ = TimeoutID(0);
62   TimeMs expiry_ = TimeMs::InfiniteFuture();
63 };
64 
65 class FakeTimeoutManager {
66  public:
67   // The `get_time` function must return the current time, relative to any
68   // epoch.
FakeTimeoutManager(std::function<TimeMs ()> get_time)69   explicit FakeTimeoutManager(std::function<TimeMs()> get_time)
70       : get_time_(std::move(get_time)) {}
71 
CreateTimeout()72   std::unique_ptr<FakeTimeout> CreateTimeout() {
73     auto timer = std::make_unique<FakeTimeout>(
74         get_time_, [this](FakeTimeout* timer) { timers_.erase(timer); });
75     timers_.insert(timer.get());
76     return timer;
77   }
CreateTimeout(webrtc::TaskQueueBase::DelayPrecision precision)78   std::unique_ptr<FakeTimeout> CreateTimeout(
79       webrtc::TaskQueueBase::DelayPrecision precision) {
80     // FakeTimeout does not support implement |precision|.
81     return CreateTimeout();
82   }
83 
84   // NOTE: This can't return a vector, as calling EvaluateHasExpired requires
85   // calling socket->HandleTimeout directly afterwards, as the owning Timer
86   // still believes it's running, and it needs to be updated to set
87   // Timer::is_running_ to false before you operate on the Timer or Timeout
88   // again.
GetNextExpiredTimeout()89   absl::optional<TimeoutID> GetNextExpiredTimeout() {
90     TimeMs now = get_time_();
91     std::vector<TimeoutID> expired_timers;
92     for (auto& timer : timers_) {
93       if (timer->EvaluateHasExpired(now)) {
94         return timer->timeout_id();
95       }
96     }
97     return absl::nullopt;
98   }
99 
100  private:
101   const std::function<TimeMs()> get_time_;
102   webrtc::flat_set<FakeTimeout*> timers_;
103 };
104 
105 }  // namespace dcsctp
106 
107 #endif  // NET_DCSCTP_TIMER_FAKE_TIMEOUT_H_
108