/*  Plzip - A parallel compressor compatible with lzip
    Copyright (C) 2009 Laszlo Ersek.
    Copyright (C) 2009, 2010 Antonio Diaz Diaz.

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#define _FILE_OFFSET_BITS 64

#include <algorithm>
#include <cerrno>
#include <climits>
#include <csignal>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <queue>
#include <string>
#include <vector>
#include <pthread.h>
#include <stdint.h>
#include <unistd.h>
#include <lzlib.h>

#include "plzip.h"


namespace {

int do_decompress( LZ_Decoder * const decoder, const int infd, const int outfd,
                   const Pretty_print & pp, const bool testing )
  {
  const int in_buffer_size = 65536, out_buffer_size = 8 * in_buffer_size;
  uint8_t in_buffer[in_buffer_size], out_buffer[out_buffer_size];

  while( true )
    {
    int in_size = std::min( LZ_decompress_write_size( decoder ), in_buffer_size );
    if( in_size > 0 )
      {
      const int max_in_size = in_size;
      in_size = readblock( infd, in_buffer, max_in_size );
      if( in_size != max_in_size && errno )
        { pp(); show_error( "read error", errno ); return 1; }
      if( in_size == 0 ) LZ_decompress_finish( decoder );
      else if( in_size != LZ_decompress_write( decoder, in_buffer, in_size ) )
        internal_error( "library error (LZ_decompress_write)" );
      }
    int out_size = LZ_decompress_read( decoder, out_buffer, out_buffer_size );
//    std::fprintf( stderr, "%5d in_size, %6d out_size.\n", in_size, out_size );
    if( out_size < 0 )
      {
      const LZ_Errno lz_errno = LZ_decompress_errno( decoder );
      if( lz_errno == LZ_header_error )
        {
        if( LZ_decompress_total_out_size( decoder ) > 0 )
          break;				// trailing garbage
        pp( "error reading member header" );
        return 1;
        }
      if( lz_errno == LZ_mem_error )
        {
        pp( "not enough memory. Find a machine with more memory" );
        return 1;
        }
      pp();
      if( lz_errno == LZ_unexpected_eof )
        {
        if( verbosity >= 0 )
          std::fprintf( stderr, "file ends unexpectedly at pos %lld\n",
                        LZ_decompress_total_in_size( decoder ) );
        return 2;
        }
      if( verbosity >= 0 )
        std::fprintf( stderr, "LZ_decompress_read error: %s.\n",
                      LZ_strerror( LZ_decompress_errno( decoder ) ) );
      return 1;
      }
    else if( out_size > 0 && outfd >= 0 )
      {
      const int wr = writeblock( outfd, out_buffer, out_size );
      if( wr != out_size )
        { pp(); show_error( "write error", errno ); return 1; }
      }
    if( LZ_decompress_finished( decoder ) == 1 ) break;
    if( in_size == 0 && out_size == 0 )
      internal_error( "library error (LZ_decompress_read)" );
    }
  if( verbosity >= 1 )
    { if( testing ) std::fprintf( stderr, "ok\n" );
      else std::fprintf( stderr, "done\n" ); }
  return 0;
  }

} // end namespace


int decompress( const int infd, const int outfd, const Pretty_print & pp,
                const bool testing )
  {
  LZ_Decoder * const decoder = LZ_decompress_open();
  int retval;

  if( !decoder || LZ_decompress_errno( decoder ) != LZ_ok )
    {
    pp( "not enough memory" );
    retval = 1;
    }
  else retval = do_decompress( decoder, infd, outfd, pp, testing );
  LZ_decompress_close( decoder );
  return retval;
  }