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_manager.h"
  15 #include "content/public/browser/download_save_info.h"
  16 #include "content/public/browser/download_url_parameters.h"
  17 #include "content/public/browser/global_request_id.h"
  18 #include "net/base/net_errors.h"
  19
  20
  21 namespace net {
  22 class URLRequest;
  23 }  // namespace net
  24
  25 namespace content {
  26 class ByteStreamWriter;
  27 class ByteStreamReader;
  28 class DownloadRequestHandle;
  29 struct DownloadCreateInfo;
  30
  31 // Forwards data to the download thread.
  32 class CONTENT_EXPORT DownloadResourceHandler
  33     : public ResourceHandler,
  34       public base::SupportsWeakPtr<DownloadResourceHandler> {
  35  public:
  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   virtual bool OnUploadProgress(int request_id,
  49                                 uint64 position,
  50                                 uint64 size) OVERRIDE;
  51
  52   virtual bool OnRequestRedirected(int request_id,
  53                                    const GURL& url,
  54                                    ResourceResponse* response,
  55                                    bool* defer) OVERRIDE;
  56
  57   // Send the download creation information to the download thread.
  58   virtual bool OnResponseStarted(int request_id,
  59                                  ResourceResponse* response,
  60                                  bool* defer) OVERRIDE;
  61
  62   // Pass-through implementation.
  63   virtual bool OnWillStart(int request_id,
  64                            const GURL& url,
  65                            bool* defer) OVERRIDE;
  66
  67   // Pass-through implementation.
  68   virtual bool OnBeforeNetworkStart(int request_id,
  69                                     const GURL& url,
  70                                     bool* defer) OVERRIDE;
  71
  72   // Create a new buffer, which will be handed to the download thread for file
  73   // writing and deletion.
  74   virtual bool OnWillRead(int request_id,
  75                           scoped_refptr<net::IOBuffer>* buf,
  76                           int* buf_size,
  77                           int min_size) OVERRIDE;
  78
  79   virtual bool OnReadCompleted(int request_id, int bytes_read,
  80                                bool* defer) OVERRIDE;
  81
  82   virtual void OnResponseCompleted(int request_id,
  83                                    const net::URLRequestStatus& status,
  84                                    const std::string& security_info,
  85                                    bool* defer) OVERRIDE;
  86
  87   // N/A to this flavor of DownloadHandler.
  88   virtual void OnDataDownloaded(int request_id, int bytes_downloaded) OVERRIDE;
  89
  90   void PauseRequest();
  91   void ResumeRequest();
  92   void CancelRequest();
  93
  94   std::string DebugString() const;
  95
  96  private:
  97   virtual ~DownloadResourceHandler();
  98
  99   // Arrange for started_cb_ to be called on the UI thread with the
 100   // below values, nulling out started_cb_.  Should only be called
 101   // on the IO thread.
 102   void CallStartedCB(DownloadItem* item, net::Error error);
 103
 104   uint32 download_id_;
 105   // This is read only on the IO thread, but may only
 106   // be called on the UI thread.
 107   DownloadUrlParameters::OnStartedCallback started_cb_;
 108   scoped_ptr<DownloadSaveInfo> save_info_;
 109
 110   // Data flow
 111   scoped_refptr<net::IOBuffer> read_buffer_;       // From URLRequest.
 112   scoped_ptr<ByteStreamWriter> stream_writer_; // To rest of system.
 113
 114   // The following are used to collect stats.
 115   base::TimeTicks download_start_time_;
 116   base::TimeTicks last_read_time_;
 117   base::TimeTicks last_stream_pause_time_;
 118   base::TimeDelta total_pause_time_;
 119   size_t last_buffer_size_;
 120   int64 bytes_read_;
 121
 122   int pause_count_;
 123   bool was_deferred_;
 124
 125   // For DCHECKing
 126   bool on_response_started_called_;
 127
 128   static const int kReadBufSize = 32768;  // bytes
 129   static const int kThrottleTimeMs = 200;  // milliseconds
 130
 131   DISALLOW_COPY_AND_ASSIGN(DownloadResourceHandler);
 132 };
 133
 134 }  // namespace content
 135
 136 #endif  // CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_RESOURCE_HANDLER_H_