| // 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. |
| |
| #ifndef CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_CORE_H_ |
| #define CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_CORE_H_ |
| |
| #include <string> |
| |
| #include "base/callback.h" |
| #include "base/macros.h" |
| #include "base/memory/scoped_ptr.h" |
| #include "base/memory/weak_ptr.h" |
| #include "content/browser/loader/resource_handler.h" |
| #include "content/public/browser/download_interrupt_reasons.h" |
| #include "content/public/browser/download_save_info.h" |
| #include "content/public/browser/download_url_parameters.h" |
| |
| namespace net { |
| class URLRequest; |
| } // namespace net |
| |
| namespace content { |
| class DownloadManagerImpl; |
| class ByteStreamReader; |
| class ByteStreamWriter; |
| class PowerSaveBlocker; |
| struct DownloadCreateInfo; |
| |
| // This class encapsulates the core logic for reading data from a URLRequest and |
| // writing it into a ByteStream. It's common to both DownloadResourceHandler and |
| // UrlDownloader. |
| // |
| // Created, lives on and dies on the IO thread. |
| class CONTENT_EXPORT DownloadRequestCore |
| : public base::SupportsWeakPtr<DownloadRequestCore> { |
| public: |
| // Size of the buffer used between the DownloadRequestCore and the |
| // downstream receiver of its output. |
| static const int kDownloadByteStreamSize; |
| |
| // |request| *must* outlive the DownloadRequestCore. |save_info| must be |
| // valid. |
| // |
| // Invokes |on_ready_to_read_callback| if a previous call to OnReadCompleted() |
| // resulted in |defer| being set to true, and DownloadRequestCore is now ready |
| // to commence reading. |
| DownloadRequestCore(net::URLRequest* request, |
| scoped_ptr<DownloadSaveInfo> save_info, |
| const base::Closure& on_ready_to_read_callback); |
| ~DownloadRequestCore(); |
| |
| // Should be called when the URLRequest::Delegate receives OnResponseStarted. |
| // Constructs a DownloadCreateInfo and a ByteStreamReader that should be |
| // passed into DownloadManagerImpl::StartDownload(). |
| // |
| // Only populates the response derived fields of DownloadCreateInfo, with the |
| // exception of |save_info|. |
| void OnResponseStarted(scoped_ptr<DownloadCreateInfo>* info, |
| scoped_ptr<ByteStreamReader>* stream_reader); |
| |
| // Starts a read cycle. Creates a new IOBuffer which can be passed into |
| // URLRequest::Read(). Call OnReadCompleted() when the Read operation |
| // completes. |
| bool OnWillRead(scoped_refptr<net::IOBuffer>* buf, |
| int* buf_size, |
| int min_size); |
| |
| // Should be called when the Read() operation completes. |defer| will be set |
| // to true if reading is to be suspended. In the latter case, once more data |
| // can be read, invokes the |on_ready_to_read_callback|. |
| bool OnReadCompleted(int bytes_read, bool* defer); |
| |
| // Called to signal that the response is complete. If the return value is |
| // something other than DOWNLOAD_INTERRUPT_REASON_NONE, then the download |
| // should be considered interrupted. |
| // |
| // It is expected that once this method is invoked, the DownloadRequestCore |
| // object will be destroyed in short order without invoking any other methods |
| // other than the destructor. |
| DownloadInterruptReason OnResponseCompleted( |
| const net::URLRequestStatus& status); |
| |
| // Called if the request should suspend reading. A subsequent |
| // OnReadCompleted() will result in |defer| being set to true. |
| // |
| // Each PauseRequest() must be balanced with a call to ResumeRequest(). |
| void PauseRequest(); |
| |
| // Balances a call to PauseRequest(). If no more pauses are outstanding and |
| // the reader end of the ByteStream is ready to receive more data, |
| // DownloadRequestCore will invoke the |on_ready_to_read_callback| to signal |
| // to the caller that the read cycles should commence. |
| void ResumeRequest(); |
| |
| std::string DebugString() const; |
| |
| protected: |
| net::URLRequest* request() const { return request_; } |
| |
| private: |
| base::Closure on_ready_to_read_callback_; |
| net::URLRequest* request_; |
| scoped_ptr<DownloadSaveInfo> save_info_; |
| |
| // Data flow |
| scoped_refptr<net::IOBuffer> read_buffer_; // From URLRequest. |
| scoped_ptr<ByteStreamWriter> stream_writer_; // To rest of system. |
| |
| // Keeps the system from sleeping while this is alive. If the |
| // system enters power saving mode while a request is alive, it can cause the |
| // request to fail and the associated download will be interrupted. |
| scoped_ptr<PowerSaveBlocker> power_save_blocker_; |
| |
| // The following are used to collect stats. |
| base::TimeTicks download_start_time_; |
| base::TimeTicks last_read_time_; |
| base::TimeTicks last_stream_pause_time_; |
| base::TimeDelta total_pause_time_; |
| size_t last_buffer_size_; |
| int64 bytes_read_; |
| |
| int pause_count_; |
| bool was_deferred_; |
| |
| // Each successful OnWillRead will yield a buffer of this size. |
| static const int kReadBufSize = 32768; // bytes |
| |
| DISALLOW_COPY_AND_ASSIGN(DownloadRequestCore); |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_CORE_H_ |