| // Copyright 2016 The Chromium Authors. All rights reserved. | 
 | // Use of this source code is governed by a BSD-style license that can be | 
 | // found in the LICENSE file. | 
 |  | 
 | #include "base/task_scheduler/scheduler_worker_stack.h" | 
 |  | 
 | #include <algorithm> | 
 |  | 
 | #include "base/logging.h" | 
 | #include "base/stl_util.h" | 
 |  | 
 | namespace base { | 
 | namespace internal { | 
 |  | 
 | SchedulerWorkerStack::SchedulerWorkerStack() = default; | 
 |  | 
 | SchedulerWorkerStack::~SchedulerWorkerStack() = default; | 
 |  | 
 | void SchedulerWorkerStack::Push(SchedulerWorker* worker) { | 
 |   DCHECK(!Contains(worker)) << "SchedulerWorker already on stack"; | 
 |   stack_.push_back(worker); | 
 | } | 
 |  | 
 | SchedulerWorker* SchedulerWorkerStack::Pop() { | 
 |   if (IsEmpty()) | 
 |     return nullptr; | 
 |   SchedulerWorker* const worker = stack_.back(); | 
 |   stack_.pop_back(); | 
 |   return worker; | 
 | } | 
 |  | 
 | SchedulerWorker* SchedulerWorkerStack::Peek() const { | 
 |   if (IsEmpty()) | 
 |     return nullptr; | 
 |   return stack_.back(); | 
 | } | 
 |  | 
 | bool SchedulerWorkerStack::Contains(const SchedulerWorker* worker) const { | 
 |   return ContainsValue(stack_, worker); | 
 | } | 
 |  | 
 | void SchedulerWorkerStack::Remove(const SchedulerWorker* worker) { | 
 |   auto it = std::find(stack_.begin(), stack_.end(), worker); | 
 |   if (it != stack_.end()) | 
 |     stack_.erase(it); | 
 | } | 
 |  | 
 | }  // namespace internal | 
 | }  // namespace base |