Resource: helper class to prohibit {add,remove}Client() calls in scope

third_party/WebKit/Source/core/fetch/Resource.h

 /*
     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2001 Dirk Mueller <mueller@kde.org>
     Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
     Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All
     rights reserved.
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
     License as published by the Free Software Foundation; either
@@ skipping 21 matching lines @@
 #include "platform/SharedBuffer.h"
 #include "platform/Timer.h"
 #include "platform/network/ResourceError.h"
 #include "platform/network/ResourceLoadPriority.h"
 #include "platform/network/ResourceRequest.h"
 #include "platform/network/ResourceResponse.h"
 #include "platform/scheduler/CancellableTaskFactory.h"
 #include "platform/tracing/web_process_memory_dump.h"
 #include "public/platform/WebDataConsumerHandle.h"
 #include "wtf/Allocator.h"
+#include "wtf/AutoReset.h"
 #include "wtf/HashCountedSet.h"
 #include "wtf/HashSet.h"
 #include "wtf/text/WTFString.h"
 #include <memory>
 
 namespace blink {
 
 struct FetchInitiatorInfo;
 class CachedMetadata;
 class FetchRequest;
@@ skipping 308 matching lines @@
   DataBufferingPolicy dataBufferingPolicy() const {
     return m_options.dataBufferingPolicy;
   }
 
   void setCachePolicyBypassingCache();
   void setLoFiStateOff();
 
   SharedBuffer* data() const { return m_data.get(); }
   void clearData() { m_data.clear(); }
 
+  class ProhibitAddRemoveClientInScope : public AutoReset<bool> {
+   public:
+    ProhibitAddRemoveClientInScope(Resource* resource)
+        : AutoReset(&resource->m_isAddRemoveClientProhibited, true) {}
+  };
+
  private:
   class ResourceCallback;
   class CachedMetadataHandlerImpl;
   class ServiceWorkerResponseCachedMetadataHandler;
 
   void cancelTimerFired(TimerBase*);
 
   void revalidationSucceeded(const ResourceResponse&);
   void revalidationFailed();
 
@@ skipping 33 matching lines @@
   unsigned m_status : 3;         // Status
 
   unsigned m_needsSynchronousCacheHit : 1;
   unsigned m_linkPreload : 1;
   bool m_isRevalidating : 1;
   bool m_isAlive : 1;
 
   ResourceIntegrityDisposition m_integrityDisposition;
   IntegrityMetadataSet m_integrityMetadata;
 
+  bool m_isAddRemoveClientProhibited;
+
   // Ordered list of all redirects followed while fetching this resource.
   Vector<RedirectPair> m_redirectChain;
 
   HeapHashCountedSet<WeakMember<ResourceClient>> m_clients;
   HeapHashCountedSet<WeakMember<ResourceClient>> m_clientsAwaitingCallback;
   HeapHashCountedSet<WeakMember<ResourceClient>> m_finishedClients;
 
   ResourceLoaderOptions m_options;
 
   double m_responseTimestamp;
@@ skipping 23 matching lines @@
 };
 
 #define DEFINE_RESOURCE_TYPE_CASTS(typeName)                   \
   DEFINE_TYPE_CASTS(typeName##Resource, Resource, resource,    \
                     resource->getType() == Resource::typeName, \
                     resource.getType() == Resource::typeName);
 
 }  // namespace blink
 
 #endif