| // 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> |
| |
| #include "base/macros.h" |
| #include "base/memory/ref_counted.h" |
| #include "base/memory/weak_ptr.h" |
| #include "content/browser/loader/layered_resource_handler.h" |
| #include "content/browser/loader/resource_handler.h" |
| #include "content/common/content_export.h" |
| #include "content/public/browser/resource_controller.h" |
| #include "net/base/io_buffer.h" |
| #include "net/url_request/url_request_status.h" |
| |
| namespace net { |
| class URLRequest; |
| } |
| |
| namespace content { |
| |
| // ResourceHandler that initiates special handling of the response if needed, |
| // based on the response's MIME type (starts downloads, sends data to some |
| // plugin types via a special channel). |
| // |
| // An InterceptingResourceHandler holds two handlers (|next_handler| and |
| // |new_handler|). It assumes the following: |
| // - OnResponseStarted on |next_handler| never sets |*defer|. |
| // - OnResponseCompleted on |next_handler| never sets |*defer|. |
| 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; |
| bool OnWillRead(scoped_refptr<net::IOBuffer>* buf, |
| int* buf_size, |
| int min_size) override; |
| bool OnReadCompleted(int bytes_read, bool* defer) 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 |
| // |payload_for_old_handler| to the old handler. Must be called after |
| // OnWillStart and OnRequestRedirected and before OnResponseStarted. One |
| // OnWillRead call is permitted beforehand. |new_handler|'s OnWillStart and |
| // OnRequestRedirected methods will not be called. |
| void UseNewHandler(std::unique_ptr<ResourceHandler> new_handler, |
| const std::string& payload_for_old_handler); |
| |
| // Used in tests. |
| ResourceHandler* new_handler_for_testing() const { |
| return new_handler_.get(); |
| } |
| |
| private: |
| enum class State { |
| // The InterceptingResourceHandler is waiting for the mime type of the |
| // response to be identified, to check if the next handler should be |
| // replaced with an appropriate one. |
| STARTING, |
| |
| // The InterceptingResourceHandler is sending the payload given via |
| // UseNewHandler to the old handler and waiting for its completion via |
| // Resume(). |
| SENDING_PAYLOAD_TO_OLD_HANDLER, |
| |
| // The InterceptingResourcHandler is calling the new handler's |
| // OnResponseStarted method and waiting for its completion via Resume(). |
| // After completion, the InterceptingResourceHandler will transition to |
| // SENDING_ON_RESPONSE_STARTED_TO_NEW_HANDLER on success. |
| SENDING_ON_WILL_START_TO_NEW_HANDLER, |
| |
| // The InterceptingResourcHandler is calling the new handler's |
| // OnResponseStarted method and waiting for its completion via Resume(). |
| // After completion, the InterceptingResourceHandler will transition to |
| // WAITING_FOR_ON_READ_COMPLETED on success. |
| SENDING_ON_RESPONSE_STARTED_TO_NEW_HANDLER, |
| |
| // The InterceptingResourcHandler is waiting for OnReadCompleted to be |
| // called. |
| WAITING_FOR_ON_READ_COMPLETED, |
| |
| // The InterceptingResourceHandler is sending the old handler's contents to |
| // 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); |
| |
| // The return value and |defer| has the same meaning as DoLoop. |
| bool SendPayloadToOldHandler(bool* defer); |
| bool SendFirstReadBufferToNewHandler(bool* defer); |
| bool SendOnResponseStartedToNewHandler(bool* defer); |
| |
| 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_ |