1 /*
2  *
3  * Copyright 2015 gRPC authors.
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *     http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  *
17  */
18 
19 #ifndef GRPCPP_IMPL_CODEGEN_TIME_H
20 #define GRPCPP_IMPL_CODEGEN_TIME_H
21 
22 #include <chrono>
23 
24 #include <grpc/impl/codegen/grpc_types.h>
25 #include <grpcpp/impl/codegen/config.h>
26 
27 namespace grpc {
28 
29 /** If you are trying to use CompletionQueue::AsyncNext with a time class that
30     isn't either gpr_timespec or std::chrono::system_clock::time_point, you
31     will most likely be looking at this comment as your compiler will have
32     fired an error below. In order to fix this issue, you have two potential
33     solutions:
34 
35       1. Use gpr_timespec or std::chrono::system_clock::time_point instead
36       2. Specialize the TimePoint class with whichever time class that you
37          want to use here. See below for two examples of how to do this.
38  */
39 template <typename T>
40 class TimePoint {
41  public:
42   // If you see the error with methods below, you may need either
43   // i) using the existing types having a conversion class such as
44   // gpr_timespec and std::chrono::system_clock::time_point or
45   // ii) writing a new TimePoint<YourType> to address your case.
46   TimePoint(const T& /*time*/) = delete;
47   gpr_timespec raw_time() = delete;
48 };
49 
50 template <>
51 class TimePoint<gpr_timespec> {
52  public:
TimePoint(const gpr_timespec & time)53   TimePoint(const gpr_timespec& time) : time_(time) {}
raw_time()54   gpr_timespec raw_time() { return time_; }
55 
56  private:
57   gpr_timespec time_;
58 };
59 
60 }  // namespace grpc
61 
62 namespace grpc {
63 
64 // from and to should be absolute time.
65 void Timepoint2Timespec(const std::chrono::system_clock::time_point& from,
66                         gpr_timespec* to);
67 void TimepointHR2Timespec(
68     const std::chrono::high_resolution_clock::time_point& from,
69     gpr_timespec* to);
70 
71 std::chrono::system_clock::time_point Timespec2Timepoint(gpr_timespec t);
72 
73 template <>
74 class TimePoint<std::chrono::system_clock::time_point> {
75  public:
TimePoint(const std::chrono::system_clock::time_point & time)76   TimePoint(const std::chrono::system_clock::time_point& time) {
77     Timepoint2Timespec(time, &time_);
78   }
raw_time()79   gpr_timespec raw_time() const { return time_; }
80 
81  private:
82   gpr_timespec time_;
83 };
84 
85 }  // namespace grpc
86 
87 #endif  // GRPCPP_IMPL_CODEGEN_TIME_H
88