text: // Copyright 2017 Google Inc.
  // Copyright 2020 The Open GEE Contributors
  //
  // Licensed under the Apache License, Version 2.0 (the "License");
  // you may not use this file except in compliance with the License.
  // You may obtain a copy of the License at
  //
  //      http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  
  //
  
  #include "Semaphore.h"
  
  namespace mttypes {
  
  
  Semaphore::Semaphore(std::uint32_t avail) :
      WaitBase(),
      avail_(avail)
  {
  }
  
  void Semaphore::Acquire(std::uint32_t num) {
    LockGuard lock(this);
    while (1) {
      if (LockedOKToAcquire()) {
        if (avail_ >= num) {
          avail_ -= num;
          return;
        }
      }
  
      LockedWait();
    }
  }
  
  void Semaphore::Release(std::uint32_t num) {
    LockGuard lock(this);
    avail_ += num;
    if (LockedOKToAcquire()) {
      if (num == 1) {
        LockedSignalOne();
      } else {
        LockedBroadcastAll();
      }
    }
  }
  
  bool Semaphore::LockedOKToAcquire(void) const {
    return !LockedIsSuspended();
  }
  
  
  } // namespace mttypes
  