69 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			69 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C++
		
	
	
	
| /*
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|  *  Copyright 2019 The WebRTC Project Authors. All rights reserved.
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|  *
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|  *  Use of this source code is governed by a BSD-style license
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|  *  that can be found in the LICENSE file in the root of the source
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|  *  tree. An additional intellectual property rights grant can be found
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|  *  in the file PATENTS.  All contributing project authors may
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|  *  be found in the AUTHORS file in the root of the source tree.
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|  */
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| 
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| #include "rtc_base/operations_chain.h"
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| 
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| #include "rtc_base/checks.h"
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| 
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| namespace rtc {
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| 
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| OperationsChain::CallbackHandle::CallbackHandle(
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|     scoped_refptr<OperationsChain> operations_chain)
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|     : operations_chain_(std::move(operations_chain)) {}
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| 
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| OperationsChain::CallbackHandle::~CallbackHandle() {
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|   RTC_DCHECK(has_run_);
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| }
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| 
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| void OperationsChain::CallbackHandle::OnOperationComplete() {
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|   RTC_DCHECK(!has_run_);
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| #ifdef RTC_DCHECK_IS_ON
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|   has_run_ = true;
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| #endif  // RTC_DCHECK_IS_ON
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|   operations_chain_->OnOperationComplete();
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|   // We have no reason to keep the |operations_chain_| alive through reference
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|   // counting anymore.
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|   operations_chain_ = nullptr;
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| }
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| 
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| // static
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| scoped_refptr<OperationsChain> OperationsChain::Create() {
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|   return new OperationsChain();
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| }
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| 
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| OperationsChain::OperationsChain() : RefCountedObject() {
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|   RTC_DCHECK_RUN_ON(&sequence_checker_);
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| }
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| 
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| OperationsChain::~OperationsChain() {
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|   // Operations keep the chain alive through reference counting so this should
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|   // not be possible. The fact that the chain is empty makes it safe to
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|   // destroy the OperationsChain on any sequence.
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|   RTC_DCHECK(chained_operations_.empty());
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| }
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| 
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| std::function<void()> OperationsChain::CreateOperationsChainCallback() {
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|   return [handle = rtc::scoped_refptr<CallbackHandle>(
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|               new CallbackHandle(this))]() { handle->OnOperationComplete(); };
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| }
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| 
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| void OperationsChain::OnOperationComplete() {
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|   RTC_DCHECK_RUN_ON(&sequence_checker_);
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|   // The front element is the operation that just completed, remove it.
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|   RTC_DCHECK(!chained_operations_.empty());
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|   chained_operations_.pop();
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|   // If there are any other operations chained, execute the next one.
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|   if (!chained_operations_.empty()) {
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|     chained_operations_.front()->Run();
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|   }
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| }
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| 
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| }  // namespace rtc
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