Initial CL for Downloads resumption.

content/public/browser/download_item.h

 // 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.
 //
 // Each download is represented by a DownloadItem, and all DownloadItems
 // are owned by the DownloadManager which maintains a global list of all
 // downloads. DownloadItems are created when a user initiates a download,
 // and exist for the duration of the browser life time.
 //
 // Download observers:
 //   DownloadItem::Observer:
 //     - allows observers to receive notifications about one download from start
 //       to completion
 // Use AddObserver() / RemoveObserver() on the appropriate download object to
 // receive state updates.
 
 #ifndef CONTENT_PUBLIC_BROWSER_DOWNLOAD_ITEM_H_
 #define CONTENT_PUBLIC_BROWSER_DOWNLOAD_ITEM_H_
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/file_path.h"
 #include "base/string16.h"
 #include "base/supports_user_data.h"
 #include "content/public/browser/download_danger_type.h"
 #include "content/public/browser/download_interrupt_reasons.h"
 #include "content/public/common/page_transition_types.h"
+#include "net/base/net_log.h"
 
 class FilePath;
 class GURL;
 
 namespace base {
 class Time;
 class TimeDelta;
 }
 
 namespace content {
@@ skipping 75 matching lines @@
   virtual void UpdateObservers() = 0;
 
   // User Actions --------------------------------------------------------------
 
   // Called when the user has validated the download of a dangerous file.
   virtual void DangerousDownloadValidated() = 0;
 
   // Allow the user to temporarily pause a download or resume a paused download.
   virtual void TogglePause() = 0;
 
+  // Resume a download that's been interrupted.
+  virtual void ResumeInterruptedDownload() = 0;
+
   // Cancel the download operation. We need to distinguish between cancels at
   // exit (DownloadManager destructor) from user interface initiated cancels
   // because at exit, the history system may not exist, and any updates to it
   // require AddRef'ing the DownloadManager in the destructor which results in
   // a DCHECK failure. Set |user_cancel| to false when canceling from at
   // exit to prevent this crash. This may result in a difference between the
   // downloaded file's size on disk, and what the history system's last record
   // of it is. At worst, we'll end up re-downloading a small portion of the file
   // when resuming a download (assuming the server supports byte ranges).
   virtual void Cancel(bool user_cancel) = 0;
@@ skipping 15 matching lines @@
   // State accessors -----------------------------------------------------------
 
   virtual int32 GetId() const = 0;
   virtual DownloadId GetGlobalId() const = 0;
   virtual DownloadState GetState() const = 0;
 
   // Only valid if |GetState() == DownloadItem::INTERRUPTED|.
   virtual DownloadInterruptReason GetLastReason() const = 0;
 
   virtual bool IsPaused() const = 0;
+  virtual bool CanResumeInterrupted() const = 0;
   virtual bool IsTemporary() const = 0;
 
   //    Convenience routines for accessing GetState() results conceptually -----
 
   // Returns true if the download needs more data.
   virtual bool IsPartialDownload() const = 0;
 
   // Returns true if the download is still receiving data.
   virtual bool IsInProgress() const = 0;
 
@@ skipping 100 matching lines @@
   virtual base::Time GetEndTime() const = 0;
 
   //    Open/Show State accessors ----------------------------------------------
 
   // Returns true if it is OK to open a folder which this file is inside.
   virtual bool CanShowInFolder() = 0;
 
   // Returns true if it is OK to open the download.
   virtual bool CanOpenDownload() = 0;
 
+  // Returns true if the download is paused or interrupted, and can be resumed.
+  virtual bool CanResumeDownload() const = 0;
+
   // Tests if a file type should be opened automatically.
   virtual bool ShouldOpenFileBasedOnExtension() = 0;
 
   // Returns true if the download will be auto-opened when complete.
   virtual bool GetOpenWhenComplete() const = 0;
 
   // Returns true if the download has been auto-opened by the system.
   virtual bool GetAutoOpened() = 0;
 
   // Returns true if the download has been opened.
@@ skipping 29 matching lines @@
   virtual void SetDisplayName(const FilePath& name) = 0;
 
   // Debug/testing -------------------------------------------------------------
   virtual std::string DebugString(bool verbose) const = 0;
   virtual void MockDownloadOpenForTesting() = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_DOWNLOAD_ITEM_H_