pdns/backends/bind/huffman.hh

   1 /*
   2     PowerDNS Versatile Database Driven Nameserver
   3     Copyright (C) 2002  PowerDNS.COM BV
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18 */
  19 #ifndef PDNS_HUFFMAN
  20 #define PDNS_HUFFMAN
  21 #include <string>
  22 #include <bitset>
  23 #include <map>
  24 #include <sstream>
  25 #include <vector>
  26 #include "../../ahuexception.hh"
  27
  28 using namespace std;
  29
  30 class HuffmanCodec
  31 {
  32 public:
  33   HuffmanCodec();
  34   void encode(const string &in, string &out);
  35   void decode(const string &compressed, string &out);
  36   void passthrough(bool);
  37   string decode(const string &in) {
  38     string tmp;
  39     decode(in,tmp);
  40     return tmp;
  41   }
  42 private:
  43   void bitify(const string &full, string &out);
  44   void unbitify(const string &in, string &full);
  45   void set(char c,const string &code);
  46   map<char,string> d_dict;
  47   vector<map<string,char> >d_rdict;
  48   size_t d_min, d_max;
  49   string d_last_compressed;
  50   string d_last_out;
  51   bool d_passthrough;
  52 };
  53 #endif /* PDNS_HUFFMAN */