content/browser/download/download_resource_handler.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_RESOURCE_HANDLER_H_
   6 #define CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_RESOURCE_HANDLER_H_
   7
   8 #include <string>
   9
  10 #include "base/callback.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "content/browser/loader/resource_handler.h"
  13 #include "content/public/browser/download_interrupt_reasons.h"
  14 #include "content/public/browser/download_manager.h"
  15 #include "content/public/browser/download_save_info.h"
  16 #include "content/public/browser/download_url_parameters.h"
  17
  18 namespace net {
  19 class URLRequest;
  20 }  // namespace net
  21
  22 namespace content {
  23 class ByteStreamReader;
  24 class ByteStreamWriter;
  25 class DownloadRequestHandle;
  26 class PowerSaveBlocker;
  27 struct DownloadCreateInfo;
  28
  29 // Forwards data to the download thread.
  30 class CONTENT_EXPORT DownloadResourceHandler
  31     : public ResourceHandler,
  32       public base::SupportsWeakPtr<DownloadResourceHandler> {
  33  public:
  34   struct DownloadTabInfo;
  35
  36   // Size of the buffer used between the DownloadResourceHandler and the
  37   // downstream receiver of its output.
  38   static const int kDownloadByteStreamSize;
  39
  40   // started_cb will be called exactly once on the UI thread.
  41   // |id| should be invalid if the id should be automatically assigned.
  42   DownloadResourceHandler(
  43       uint32 id,
  44       net::URLRequest* request,
  45       const DownloadUrlParameters::OnStartedCallback& started_cb,
  46       scoped_ptr<DownloadSaveInfo> save_info);
  47
  48   bool OnUploadProgress(uint64 position, uint64 size) override;
  49
  50   bool OnRequestRedirected(const net::RedirectInfo& redirect_info,
  51                            ResourceResponse* response,
  52                            bool* defer) override;
  53
  54   // Send the download creation information to the download thread.
  55   bool OnResponseStarted(ResourceResponse* response, bool* defer) override;
  56
  57   // Pass-through implementation.
  58   bool OnWillStart(const GURL& url, bool* defer) override;
  59
  60   // Pass-through implementation.
  61   bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
  62
  63   // Create a new buffer, which will be handed to the download thread for file
  64   // writing and deletion.
  65   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
  66                   int* buf_size,
  67                   int min_size) override;
  68
  69   bool OnReadCompleted(int bytes_read, bool* defer) override;
  70
  71   void OnResponseCompleted(const net::URLRequestStatus& status,
  72                            const std::string& security_info,
  73                            bool* defer) override;
  74
  75   // N/A to this flavor of DownloadHandler.
  76   void OnDataDownloaded(int bytes_downloaded) override;
  77
  78   void PauseRequest();
  79   void ResumeRequest();
  80
  81   // May result in this object being deleted by its owner.
  82   void CancelRequest();
  83
  84   std::string DebugString() const;
  85
  86  private:
  87   ~DownloadResourceHandler() override;
  88
  89   // Arrange for started_cb_ to be called on the UI thread with the
  90   // below values, nulling out started_cb_.  Should only be called
  91   // on the IO thread.
  92   void CallStartedCB(DownloadItem* item,
  93                      DownloadInterruptReason interrupt_reason);
  94
  95   uint32 download_id_;
  96   // This is read only on the IO thread, but may only
  97   // be called on the UI thread.
  98   DownloadUrlParameters::OnStartedCallback started_cb_;
  99   scoped_ptr<DownloadSaveInfo> save_info_;
 100
 101   // Stores information about the download that must be acquired on the UI
 102   // thread before StartOnUIThread is called.
 103   // Created on IO thread, but only accessed on UI thread. |tab_info_| holds
 104   // the pointer until we pass it off to StartOnUIThread or DeleteSoon.
 105   // Marked as a scoped_ptr<> to indicate ownership of the structure, but
 106   // deletion must occur on the IO thread.
 107   scoped_ptr<DownloadTabInfo> tab_info_;
 108
 109   // Data flow
 110   scoped_refptr<net::IOBuffer> read_buffer_;       // From URLRequest.
 111   scoped_ptr<ByteStreamWriter> stream_writer_; // To rest of system.
 112
 113   // Keeps the system from sleeping while this ResourceHandler is alive. If the
 114   // system enters power saving mode while a request is alive, it can cause the
 115   // request to fail and the associated download will be interrupted.
 116   scoped_ptr<PowerSaveBlocker> power_save_blocker_;
 117
 118   // The following are used to collect stats.
 119   base::TimeTicks download_start_time_;
 120   base::TimeTicks last_read_time_;
 121   base::TimeTicks last_stream_pause_time_;
 122   base::TimeDelta total_pause_time_;
 123   size_t last_buffer_size_;
 124   int64 bytes_read_;
 125
 126   int pause_count_;
 127   bool was_deferred_;
 128
 129   // For DCHECKing
 130   bool on_response_started_called_;
 131
 132   static const int kReadBufSize = 32768;  // bytes
 133   static const int kThrottleTimeMs = 200;  // milliseconds
 134
 135   DISALLOW_COPY_AND_ASSIGN(DownloadResourceHandler);
 136 };
 137
 138 }  // namespace content
 139
 140 #endif  // CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_RESOURCE_HANDLER_H_