Read and restore persisted slice info

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:
@@ skipping 84 matching lines @@
 
     // Called when the download is being destroyed. This happens after
     // every OnDownloadRemoved() as well as when the DownloadManager is going
     // down.
     virtual void OnDownloadDestroyed(DownloadItem* download) {}
 
    protected:
     virtual ~Observer() {}
   };
 
+  struct CONTENT_EXPORT ReceivedSlice {
+    ReceivedSlice(int64_t offset, int64_t received_bytes)
+        : offset(offset), received_bytes(received_bytes) {}
+
+    bool operator==(const ReceivedSlice& rhs) const {
+      return offset == rhs.offset && received_bytes == rhs.received_bytes;
+    }
+
+    int64_t offset;
+    int64_t received_bytes;
+  };
+
   ~DownloadItem() override {}
 
   // Observation ---------------------------------------------------------------
 
   virtual void AddObserver(DownloadItem::Observer* observer) = 0;
   virtual void RemoveObserver(DownloadItem::Observer* observer) = 0;
   virtual void UpdateObservers() = 0;
 
   // User Actions --------------------------------------------------------------
 
@@ skipping 227 matching lines @@
   // final name.
   virtual bool AllDataSaved() const = 0;
 
   // Total number of expected bytes. Returns -1 if the total size is unknown.
   virtual int64_t GetTotalBytes() const = 0;
 
   // Total number of bytes that have been received and written to the download
   // file.
   virtual int64_t GetReceivedBytes() const = 0;
 
+  // Return the slices that have been received so far. This is only used
+  // when parallel downloading is enabled.
+  virtual const std::vector<ReceivedSlice>& GetReceivedSlices() const = 0;
+
   // Time the download was first started. This timestamp is always valid and
   // doesn't change.
   virtual base::Time GetStartTime() const = 0;
 
   // Time the download was marked as complete. Returns base::Time() if the
   // download hasn't reached a completion state yet.
   virtual base::Time GetEndTime() const = 0;
 
   //    Open/Show State accessors ----------------------------------------------
 
@@ skipping 46 matching lines @@
   // return |name|. Has no effect on the final target filename.
   virtual void SetDisplayName(const base::FilePath& name) = 0;
 
   // Debug/testing -------------------------------------------------------------
   virtual std::string DebugString(bool verbose) const = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_DOWNLOAD_ITEM_H_