Use defer out-params instead of ResourceDispatcherHostImpl::PauseRequest(...true)

content/browser/renderer_host/resource_handler.h

 // Copyright (c) 2012 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.
 
 // This is the browser side of the resource dispatcher, it receives requests
 // from the RenderProcessHosts, and dispatches them to URLRequests. It then
 // fowards the messages from the URLRequests back to the correct process for
 // handling.
 //
 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
@@ skipping 33 matching lines @@
 
   // The request was redirected to a new URL.  |*defer| has an initial value of
   // false.  Set |*defer| to true to defer the redirect.  The redirect may be
   // followed later on via ResourceDispatcherHost::FollowDeferredRedirect.  If
   // the handler returns false, then the request is cancelled.
   virtual bool OnRequestRedirected(int request_id, const GURL& url,
                                    content::ResourceResponse* response,
                                    bool* defer) = 0;
 
   // Response headers and meta data are available.  If the handler returns
-  // false, then the request is cancelled.
+  // false, then the request is cancelled.  Set |*defer| to true to defer
+  // processing of the response.  Call ResourceDispatcherHostImpl::
+  // ResumeDeferredRequest to continue processing the response.
   virtual bool OnResponseStarted(int request_id,
-                                 content::ResourceResponse* response) = 0;
+                                 content::ResourceResponse* response,
+                                 bool* defer) = 0;
 
   // Called before the net::URLRequest for |request_id| (whose url is |url|) is
   // to be started.  If the handler returns false, then the request is
   // cancelled.  Otherwise if the return value is true, the ResourceHandler can
   // delay the request from starting by setting |*defer = true|.  A deferred
   // request will not have called net::URLRequest::Start(), and will not resume
   // until someone calls ResourceDispatcherHost::StartDeferredRequest().
   virtual bool OnWillStart(int request_id, const GURL& url, bool* defer) = 0;
 
   // Data will be read for the response.  Upon success, this method places the
   // size and address of the buffer where the data is to be written in its
   // out-params.  This call will be followed by either OnReadCompleted or
   // OnResponseCompleted, at which point the buffer may be recycled.
   //
   // If this method returns false, then the request will not be read.  This is
   // normally used in conjunction with ResourceDispatcherHost::PauseRequest to
   // pause the processing of the request.  When the request is later resumed,
   // OnWillRead will be called again.
   virtual bool OnWillRead(int request_id,
                           net::IOBuffer** buf,
                           int* buf_size,
                           int min_size) = 0;
 
   // Data (*bytes_read bytes) was written into the buffer provided by
   // OnWillRead.  A return value of false cancels the request, true continues
-  // reading data.
-  virtual bool OnReadCompleted(int request_id, int* bytes_read) = 0;
+  // reading data.  Set |*defer| to true to defer reading more response data.
+  // Call ResourceDispatcherHostImpl::ResumeDeferredRequest to continue reading
+  // response data.
+  virtual bool OnReadCompleted(int request_id, int* bytes_read,
+                               bool* defer) = 0;
 
   // The response is complete.  The final response status is given.  Returns
   // false if the handler is deferring the call to a later time.  Otherwise,
   // the request will be destroyed upon return.
   virtual bool OnResponseCompleted(int request_id,
                                    const net::URLRequestStatus& status,
                                    const std::string& security_info) = 0;
 
   // Signals that the request is closed (i.e. about to be deleted).  This is a
   // signal that the associated net::URLRequest isn't valid anymore.
   virtual void OnRequestClosed() = 0;
 
   // This notification is synthesized by the RedirectToFileResourceHandler
   // to indicate progress of 'download_to_file' requests. OnReadCompleted
   // calls are consumed by the RedirectToFileResourceHandler and replaced
   // with OnDataDownloaded calls.
   virtual void OnDataDownloaded(int request_id, int bytes_downloaded) {}
 
  protected:
   friend class content::BrowserThread;
   friend class base::RefCountedThreadSafe<
       ResourceHandler, content::BrowserThread::DeleteOnIOThread>;
   friend class base::DeleteHelper<ResourceHandler>;
 
   virtual ~ResourceHandler() {}
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RESOURCE_HANDLER_H_