Line data    Source code

       1             : /* Copyright (C) 2011 Wildfire Games.
       2             :  * This file is part of 0 A.D.
       3             :  *
       4             :  * 0 A.D. is free software: you can redistribute it and/or modify
       5             :  * it under the terms of the GNU General Public License as published by
       6             :  * the Free Software Foundation, either version 2 of the License, or
       7             :  * (at your option) any later version.
       8             :  *
       9             :  * 0 A.D. is distributed in the hope that it will be useful,
      10             :  * but WITHOUT ANY WARRANTY; without even the implied warranty of
      11             :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      12             :  * GNU General Public License for more details.
      13             :  *
      14             :  * You should have received a copy of the GNU General Public License
      15             :  * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
      16             :  */
      17             : 
      18             : #include "precompiled.h"
      19             : 
      20             : #include "Compress.h"
      21             : 
      22             : #include "lib/byte_order.h"
      23             : #include "lib/external_libraries/zlib.h"
      24             : 
      25           0 : void CompressZLib(const std::string& data, std::string& out, bool includeLengthHeader)
      26             : {
      27           0 :     uLongf maxCompressedSize = compressBound(data.size());
      28           0 :     uLongf destLen = maxCompressedSize;
      29             : 
      30           0 :     out.clear();
      31             : 
      32           0 :     if (includeLengthHeader)
      33             :     {
      34             :         // Add a 4-byte uncompressed length header to the output
      35           0 :         out.resize(maxCompressedSize + 4);
      36           0 :         write_le32((void*)out.c_str(), data.size());
      37           0 :         int zok = compress((Bytef*)out.c_str() + 4, &destLen, (const Bytef*)data.c_str(), data.size());
      38           0 :         ENSURE(zok == Z_OK);
      39           0 :         out.resize(destLen + 4);
      40             :     }
      41             :     else
      42             :     {
      43           0 :         out.resize(maxCompressedSize);
      44           0 :         int zok = compress((Bytef*)out.c_str(), &destLen, (const Bytef*)data.c_str(), data.size());
      45           0 :         ENSURE(zok == Z_OK);
      46           0 :         out.resize(destLen);
      47             :     }
      48           0 : }
      49             : 
      50           0 : void DecompressZLib(const std::string& data, std::string& out, bool includeLengthHeader)
      51             : {
      52           0 :     ENSURE(includeLengthHeader); // otherwise we don't know how much to allocate
      53             : 
      54           0 :     out.clear();
      55           0 :     out.resize(read_le32(data.c_str()));
      56             : 
      57           0 :     uLongf destLen = out.size();
      58           0 :     int zok = uncompress((Bytef*)out.c_str(), &destLen, (const Bytef*)data.c_str() + 4, data.size() - 4);
      59           0 :     ENSURE(zok == Z_OK);
      60           0 :     ENSURE(destLen == out.size());
      61             : 
      62             :     // TODO: better error reporting might be nice
      63           3 : }