Cleanup: have common HttpResponseHeaders routine to update with range

net/http/http_response_headers.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 NET_HTTP_HTTP_RESPONSE_HEADERS_H_
 #define NET_HTTP_HTTP_RESPONSE_HEADERS_H_
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/containers/hash_tables.h"
 #include "base/memory/ref_counted.h"
 #include "base/strings/string_piece.h"
 #include "net/base/net_export.h"
 #include "net/base/net_log.h"
 #include "net/http/http_version.h"
 
 class Pickle;
 class PickleIterator;
 
 namespace base {
 class Time;
 class TimeDelta;
 }
 
 namespace net {
 
+class HttpByteRange;
+
 // HttpResponseHeaders: parses and holds HTTP response headers.
 class NET_EXPORT HttpResponseHeaders
     : public base::RefCountedThreadSafe<HttpResponseHeaders> {
  public:
   // Persist options.
   typedef int PersistOptions;
   static const PersistOptions PERSIST_RAW = -1;  // Raw, unparsed headers.
   static const PersistOptions PERSIST_ALL = 0;  // Parsed headers.
   static const PersistOptions PERSIST_SANS_COOKIES = 1 << 0;
   static const PersistOptions PERSIST_SANS_CHALLENGES = 1 << 1;
@@ skipping 37 matching lines @@
   // EOL termination, just [<header-name>: <header-values>]
   // If a header with the same name is already stored, the two headers are not
   // merged together by this method; the one provided is simply put at the
   // end of the list.
   void AddHeader(const std::string& header);
 
   // Replaces the current status line with the provided one (|new_status| should
   // not have any EOL).
   void ReplaceStatusLine(const std::string& new_status);
 
+  // Updates headers (Content-Length and Content-Range) in the |headers| to
+  // include the right content length and range for |byte_range|.  This also
+  // updates HTTP status line if |replace_status_line| is true.  It is not valid
+  // to give invalid |byte_range|.

[mmenke, 2014/03/06 18:18:48]

This also doesn't work for suffix byte ranges, or those unbounded on the right.

[rvargas (doing something else), 2014/03/06 19:24:00]

Maybe the right message is that byte_range should come from a valid response, or
that should be usable for a response (as opposed to for a request)... or maybe
that is implied by the fact that this attempts to use that range for a response
:)

[kinuko, 2014/03/07 05:05:14]

I tried to improve the comment... I'm still learning how byte range works and I
hope the new comment makes sense.

+  void UpdateWithNewRange(const HttpByteRange& byte_range,
+                          int64 resource_size,
+                          bool replace_status_line);
+
   // Creates a normalized header string.  The output will be formatted exactly
   // like so:
   //     HTTP/<version> <status_code> <status_text>\n
   //     [<header-name>: <header-values>\n]*
   // meaning, each line is \n-terminated, and there is no extra whitespace
   // beyond the single space separators shown (of course, values can contain
   // whitespace within them).  If a given header-name appears more than once
   // in the set of headers, they are combined into a single line like so:
   //     <header-name>: <header-value1>, <header-value2>, ...<header-valueN>\n
   //
@@ skipping 306 matching lines @@
 
   // The parsed http version number (not normalized).
   HttpVersion parsed_http_version_;
 
   DISALLOW_COPY_AND_ASSIGN(HttpResponseHeaders);
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_RESPONSE_HEADERS_H_