xref: /aosp_15_r20/external/federated-compute/fcp/base/simulated_clock.cc (revision 14675a029014e728ec732f129a32e299b2da0601)
1 /*
2  * Copyright 2020 Google LLC
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "fcp/base/simulated_clock.h"
18 
19 namespace fcp {
20 
Now()21 absl::Time SimulatedClock::Now() {
22   absl::MutexLock lock(mutex());
23   return NowLocked();
24 }
25 
NowLocked()26 absl::Time SimulatedClock::NowLocked() {
27   mutex()->AssertHeld();
28   return now_;
29 }
30 
Sleep(absl::Duration d)31 void SimulatedClock::Sleep(absl::Duration d) {
32   absl::Time current;
33   {
34     absl::MutexLock lock(mutex());
35     current = now_;
36   }
37   absl::Time deadline = current + d;
38   while (true) {
39     {
40       absl::MutexLock lock(mutex());
41       current = now_;
42     }
43     if (current >= deadline) {
44       return;
45     }
46   }
47 }
48 
SetTime(absl::Time t)49 void SimulatedClock::SetTime(absl::Time t) {
50   {
51     absl::MutexLock lock(mutex());
52     now_ = t;
53   }
54   DispatchWakeups();
55 }
56 
AdvanceTime(absl::Duration d)57 void SimulatedClock::AdvanceTime(absl::Duration d) {
58   {
59     absl::MutexLock lock(mutex());
60     now_ += d;
61   }
62   DispatchWakeups();
63 }
64 
65 }  // namespace fcp
66 
67