naiveproxy/net/tools/huffman_trie/trie/trie_writer.h
2018-12-09 21:59:24 -05:00

65 lines
1.8 KiB
C++

// Copyright 2018 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_TOOLS_HUFFMAN_TRIE_TRIE_TRIE_WRITER_H_
#define NET_TOOLS_HUFFMAN_TRIE_TRIE_TRIE_WRITER_H_
#include <string>
#include <vector>
#include "net/tools/huffman_trie/bit_writer.h"
#include "net/tools/huffman_trie/huffman/huffman_builder.h"
#include "net/tools/huffman_trie/trie_entry.h"
namespace net {
namespace huffman_trie {
enum : uint8_t { kTerminalValue = 0, kEndOfTableValue = 127 };
class TrieWriter {
public:
TrieWriter(const HuffmanRepresentationTable& huffman_table,
HuffmanBuilder* huffman_builder);
~TrieWriter();
// Constructs a trie containing all |entries|. The output is written to
// |buffer_| and |*position| is set to the position of the trie root. Returns
// true on success and false on failure.
bool WriteEntries(const TrieEntries& entries, uint32_t* position);
// Returns the position |buffer_| is currently at. The returned value
// represents the number of bits.
uint32_t position() const;
// Flushes |buffer_|.
void Flush();
// Returns the trie bytes. Call Flush() first to ensure the buffer is
// complete.
const std::vector<uint8_t>& bytes() const { return buffer_.bytes(); }
protected:
const HuffmanRepresentationTable& huffman_table() const {
return huffman_table_;
}
HuffmanBuilder* huffman_builder() { return huffman_builder_; }
private:
bool WriteDispatchTables(ReversedEntries::iterator start,
ReversedEntries::iterator end,
uint32_t* position);
BitWriter buffer_;
const HuffmanRepresentationTable& huffman_table_;
HuffmanBuilder* huffman_builder_;
};
} // namespace huffman_trie
} // namespace net
#endif // NET_TOOLS_HUFFMAN_TRIE_TRIE_TRIE_WRITER_H_