Range request support for parallel download in DownloadRequestCore.

content/public/browser/download_url_parameters.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.
 
 #ifndef CONTENT_PUBLIC_BROWSER_DOWNLOAD_URL_PARAMETERS_H_
 #define CONTENT_PUBLIC_BROWSER_DOWNLOAD_URL_PARAMETERS_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 150 matching lines @@
     save_info_.file_path = file_path;
   }
 
   // Suggested filename for the download. The suggestion can be overridden by
   // either a Content-Disposition response header or a |file_path|.
   void set_suggested_name(const base::string16& suggested_name) {
     save_info_.suggested_name = suggested_name;
   }
 
   // If |offset| is non-zero, then a byte range request will be issued to fetch
-  // the range of bytes starting at |offset| through to the end of thedownload.
+  // the range of bytes starting at |offset|.
+  // Use |set_length| to specify the last byte position, or the range
+  // request will be "Range:bytes={offset}-" to retrieve the rest of the file.
   void set_offset(int64_t offset) { save_info_.offset = offset; }
 
+  // When |length| > 0, the range of bytes will be from
+  // |save_info_.offset| to |save_info_.offset| + |length| - 1.
+  // See |DownloadSaveInfo.length|.
+  void set_length(int64_t length) { save_info_.length = length; }
+
   // If |offset| is non-zero, then |hash_of_partial_file| contains the raw
   // SHA-256 hash of the first |offset| bytes of the target file. Only
   // meaningful if a partial file exists and is identified by either the
   // |file_path()| or |file()|.
   void set_hash_of_partial_file(const std::string& hash_of_partial_file) {
     save_info_.hash_of_partial_file = hash_of_partial_file;
   }
 
   // If |offset| is non-zero, then |hash_state| indicates the SHA-256 hash state
   // of the first |offset| bytes of the target file. In this case, the prefix
@@ skipping 48 matching lines @@
 
   const RequestHeadersType& request_headers() const { return request_headers_; }
   net::URLRequestContextGetter* url_request_context_getter() {
     return url_request_context_getter_.get();
   }
   const base::FilePath& file_path() const { return save_info_.file_path; }
   const base::string16& suggested_name() const {
     return save_info_.suggested_name;
   }
   int64_t offset() const { return save_info_.offset; }
+  int64_t length() const { return save_info_.length; }
   const std::string& hash_of_partial_file() const {
     return save_info_.hash_of_partial_file;
   }
   bool prompt() const { return save_info_.prompt_for_save_location; }
   const GURL& url() const { return url_; }
   bool do_not_prompt_for_login() const { return do_not_prompt_for_login_; }
 
   // STATE_CHANGING: Return the BlobDataHandle.
   std::unique_ptr<storage::BlobDataHandle> GetBlobDataHandle() {
     return std::move(blob_data_handle_);
@@ skipping 24 matching lines @@
   GURL url_;
   bool do_not_prompt_for_login_;
   std::unique_ptr<storage::BlobDataHandle> blob_data_handle_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadUrlParameters);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_DOWNLOAD_URL_PARAMETERS_H_