Update HPACK implementation to draft 05

net/spdy/hpack_encoding_context.h

 // Copyright 2014 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_SPDY_HPACK_ENCODING_CONTEXT_H_
 #define NET_SPDY_HPACK_ENCODING_CONTEXT_H_
 
 #include <cstddef>
 #include <deque>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/macros.h"
 #include "base/strings/string_piece.h"
 #include "net/base/net_export.h"
 #include "net/spdy/hpack_header_table.h"
 
 // All section references below are to
-// http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-04
+// http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-05
 // .
 
 namespace net {
 
 // An encoding context is simply a header table and its associated
 // reference set and a static table.
 class NET_EXPORT_PRIVATE HpackEncodingContext {
  public:
   // The constant returned by GetTouchesAt() if the indexed entry
   // hasn't been touched (which is distinct from having a touch count
   // of 0).
   //
   // TODO(akalin): The distinction between untouched and having a
   // touch count of 0 is confusing. Think of a better way to represent
   // this state.
   static const uint32 kUntouched;
 
   HpackEncodingContext();
 
   ~HpackEncodingContext();
 
+  uint32 GetMutableEntryCount() const;
+
   uint32 GetEntryCount() const;
 
-  // For all accessor below, index must be < GetEntryCount().
+  // For all read accessors below, index must be >= 1 and <=
+  // GetEntryCount().  For all mutating accessors below, index must be
+  // >= 1 and <= GetMutableEntryCount().
 
   // The StringPieces returned by Get{Name,Value}At() live as long as
   // the next call to SetMaxSize() or the Process*() functions.
 
   base::StringPiece GetNameAt(uint32 index) const;
 
   base::StringPiece GetValueAt(uint32 index) const;
 
   bool IsReferencedAt(uint32 index) const;
 
@@ skipping 13 matching lines @@
 
   // Sets the maximum size of the encoding text, evicting entries if
   // necessary.
   void SetMaxSize(uint32 max_size);
 
   // The Process*() functions below return true on success and false
   // if an error was encountered.
 
   // Tries to update the encoding context given an indexed header
   // opcode for the given index as described in 3.2.1. new_index is
-  // filled in with the index of a mutable entry, or -1 if one was not
+  // filled in with the index of a mutable entry, or 0 if one was not
   // able to be created. removed_referenced_indices is filled in with
   // the indices of all entries removed from the reference set.
   bool ProcessIndexedHeader(uint32 index,
-                            int32* new_index,
+                            uint32* new_index,
                             std::vector<uint32>* removed_referenced_indices);
 
   // Tries to update the encoding context given a literal header with
   // incremental indexing opcode for the given name and value as
   // described in 3.2.1. index is filled in with the index of the new
-  // entry if the header was successfully indexed, or -1 if
+  // entry if the header was successfully indexed, or 0 if
   // not. removed_referenced_indices is filled in with the indices of
   // all entries removed from the reference set.
   bool ProcessLiteralHeaderWithIncrementalIndexing(
       base::StringPiece name,
       base::StringPiece value,
-      int32* index,
+      uint32* index,
       std::vector<uint32>* removed_referenced_indices);
 
  private:
   HpackHeaderTable header_table_;
 
   DISALLOW_COPY_AND_ASSIGN(HpackEncodingContext);
 };
 
 }  // namespace net
 
 #endif  // NET_SPDY_HPACK_ENCODING_CONTEXT_H_