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