xref: /aosp_15_r20/external/abseil-cpp/absl/synchronization/internal/pthread_waiter.h (revision 9356374a3709195abf420251b3e825997ff56c0f)
1 // Copyright 2023 The Abseil Authors.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //      https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 //
15 
16 #ifndef ABSL_SYNCHRONIZATION_INTERNAL_PTHREAD_WAITER_H_
17 #define ABSL_SYNCHRONIZATION_INTERNAL_PTHREAD_WAITER_H_
18 
19 #if !defined(_WIN32) && !defined(__MINGW32__)
20 #include <pthread.h>
21 
22 #include "absl/base/config.h"
23 #include "absl/synchronization/internal/kernel_timeout.h"
24 #include "absl/synchronization/internal/waiter_base.h"
25 
26 namespace absl {
27 ABSL_NAMESPACE_BEGIN
28 namespace synchronization_internal {
29 
30 #define ABSL_INTERNAL_HAVE_PTHREAD_WAITER 1
31 
32 class PthreadWaiter : public WaiterCrtp<PthreadWaiter> {
33  public:
34   PthreadWaiter();
35 
36   bool Wait(KernelTimeout t);
37   void Post();
38   void Poke();
39 
40   static constexpr char kName[] = "PthreadWaiter";
41 
42  private:
43   int TimedWait(KernelTimeout t);
44 
45   // REQUIRES: mu_ must be held.
46   void InternalCondVarPoke();
47 
48   pthread_mutex_t mu_;
49   pthread_cond_t cv_;
50   int waiter_count_;
51   int wakeup_count_;  // Unclaimed wakeups.
52 };
53 
54 }  // namespace synchronization_internal
55 ABSL_NAMESPACE_END
56 }  // namespace absl
57 
58 #endif  // !defined(_WIN32) && !defined(__MINGW32__)
59 
60 #endif  // ABSL_SYNCHRONIZATION_INTERNAL_PTHREAD_WAITER_H_
61