Refactor ResourceHandler API.

content/browser/loader/intercepting_resource_handler.h

 // 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.
 
 #ifndef CONTENT_BROWSER_LOADER_INTERCEPTING_RESOURCE_HANDLER_H_
 #define CONTENT_BROWSER_LOADER_INTERCEPTING_RESOURCE_HANDLER_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 24 matching lines @@
 class CONTENT_EXPORT InterceptingResourceHandler
     : public LayeredResourceHandler,
       public ResourceController {
  public:
   InterceptingResourceHandler(std::unique_ptr<ResourceHandler> next_handler,
                               net::URLRequest* request);
   ~InterceptingResourceHandler() override;
 
   // ResourceHandler implementation:
   void SetController(ResourceController* controller) override;
-  bool OnResponseStarted(ResourceResponse* response, bool* defer) override;
+  void OnResponseStarted(ResourceResponse* response,
+                         bool* defer_or_cancel) override;
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                   int* buf_size,
                   int min_size) override;
-  bool OnReadCompleted(int bytes_read, bool* defer) override;
+  void OnReadCompleted(int bytes_read, bool* defer_or_cancel) override;
   void OnResponseCompleted(const net::URLRequestStatus& status,
                            bool* defer) override;
 
   // ResourceController implementation:
   void Cancel() override;
   void CancelAndIgnore() override;
   void CancelWithError(int error_code) override;
   void Resume() override;
 
   // Replaces the next handler with |new_handler|, sending
@@ skipping 41 matching lines @@
     // the new handler and waiting for its completion via Resume().
     SENDING_BUFFER_TO_NEW_HANDLER,
 
     // The InterceptingResourceHandler has replaced its next ResourceHandler if
     // needed, and has ensured the buffered read data was properly transmitted
     // to the new ResourceHandler. The InterceptingResourceHandler now acts as
     // a pass-through ResourceHandler.
     PASS_THROUGH,
   };
 
-  // Runs necessary operations depending on |state_|. Returns false when an
-  // error happens, and set |*defer| to true if the operation continues upon
-  // return.
-  bool DoLoop(bool* defer);
+  // Runs necessary operations depending on |state_|. Set |*defer_or_cancel| to
+  // true if the operation is not yet complete, and will invoke Resume() or
+  // Cancel() in the future, or if Cancel() was invoked synchronously.
+  void DoLoop(bool* defer_or_cancel);
 
-  // The return value and |defer| has the same meaning as DoLoop.
-  bool SendPayloadToOldHandler(bool* defer);
-  bool SendFirstReadBufferToNewHandler(bool* defer);
-  bool SendOnResponseStartedToNewHandler(bool* defer);
+  // |defer_or_cancel| has the same meaning as DoLoop.
+  void SendPayloadToOldHandler(bool* defer_or_cancel);
+  void SendFirstReadBufferToNewHandler(bool* defer_or_cancel);
+  void SendOnResponseStartedToNewHandler(bool* defer_or_cancel);
 
   State state_ = State::STARTING;
 
   std::unique_ptr<ResourceHandler> new_handler_;
   std::string payload_for_old_handler_;
   size_t payload_bytes_written_ = 0;
 
   // Result of the first read, that may have to be passed to an alternate
   // ResourceHandler instead of the original ResourceHandler.
   scoped_refptr<net::IOBuffer> first_read_buffer_;
   // Instead of |first_read_buffer_|, this handler creates a new IOBuffer with
   // the same size and return it to the client.
   scoped_refptr<net::IOBuffer> first_read_buffer_double_;
   size_t first_read_buffer_size_ = 0;
   size_t first_read_buffer_bytes_read_ = 0;
   size_t first_read_buffer_bytes_written_ = 0;
 
   scoped_refptr<ResourceResponse> response_;
 
   DISALLOW_COPY_AND_ASSIGN(InterceptingResourceHandler);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_LOADER_INTERCEPTING_RESOURCE_HANDLER_H_