HPACK: Refactor and simplify HpackOutputStream

net/spdy/hpack_output_stream.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_OUTPUT_STREAM_H_
 #define NET_SPDY_HPACK_OUTPUT_STREAM_H_
 
 #include <map>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/macros.h"
 #include "base/strings/string_piece.h"
 #include "net/base/net_export.h"
-#include "net/spdy/hpack_constants.h"  // For HpackPrefix.
+#include "net/spdy/hpack_constants.h"
 
 // All section references below are to
 // http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-06
 
 namespace net {
 
 // An HpackOutputStream handles all the low-level details of encoding
 // header fields.
 class NET_EXPORT_PRIVATE HpackOutputStream {
  public:
-  // |max_string_literal_size| is the largest that any one string
-  // |literal (header name or header value) can be.
-  explicit HpackOutputStream(uint32 max_string_literal_size);
+  explicit HpackOutputStream();
   ~HpackOutputStream();
 
-  // Corresponds to 4.2.
-  void AppendIndexedHeader(uint32 index_or_zero);
-
-  // Corresponds to 4.3.1 (second form). Returns whether or not the
-  // append was successful; if the append was unsuccessful, no other
-  // member function may be called.
-  bool AppendLiteralHeaderNoIndexingWithName(base::StringPiece name,
-                                             base::StringPiece value);
-
-  // Moves the internal buffer to the given string and clears all
-  // internal state.
-  void TakeString(std::string* output);
-
   // Appends the lower |bit_size| bits of |bits| to the internal buffer.
   //
   // |bit_size| must be > 0 and <= 8. |bits| must not have any bits
   // set other than the lower |bit_size| bits.
   void AppendBits(uint8 bits, size_t bit_size);
 
-  // Accessors for testing.
-
-  void AppendBitsForTest(uint8 bits, size_t size) {
-    AppendBits(bits, size);
-  }
-
-  void AppendUint32ForTest(uint32 I) {
-    AppendUint32(I);
-  }
-
-  bool AppendStringLiteralForTest(base::StringPiece str) {
-    return AppendStringLiteral(str);
-  }
-
- private:
   // Simply forwards to AppendBits(prefix.bits, prefix.bit-size).
   void AppendPrefix(HpackPrefix prefix);
 
+  // Directly appends |buffer|.
+  void AppendBytes(base::StringPiece buffer);
+
   // Appends the given integer using the representation described in
   // 4.1.1. If the internal buffer ends on a byte boundary, the prefix
   // length N is taken to be 8; otherwise, it is taken to be the
   // number of bits to the next byte boundary.
   //
   // It is guaranteed that the internal buffer will end on a byte
   // boundary after this function is called.
   void AppendUint32(uint32 I);
 
-  // Appends the given string using the representation described in
-  // 4.1.2. The internal buffer must end on a byte boundary, and it is
-  // guaranteed that the internal buffer will end on a byte boundary
-  // after this function is called. Returns whether or not the append
-  // was successful; if the append was unsuccessful, no other member
-  // function may be called.
-  bool AppendStringLiteral(base::StringPiece str);
+  // Swaps the interal buffer with |output|.
+  void TakeString(std::string* output);
 
-  const uint32 max_string_literal_size_;
-
+ private:
   // The internal bit buffer.
   std::string buffer_;
 
   // If 0, the buffer ends on a byte boundary. If non-zero, the buffer
   // ends on the most significant nth bit. Guaranteed to be < 8.
   size_t bit_offset_;
 
   DISALLOW_COPY_AND_ASSIGN(HpackOutputStream);
 };
 
 }  // namespace net
 
 #endif  // NET_SPDY_HPACK_OUTPUT_STREAM_H_