---

EndianIn.cpp

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/*
    TEDDY - General graphics application library
    Copyright (C) 1999-2002  Timo Suoranta
    tksuoran@cc.helsinki.fi

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library 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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    $Id: EndianIn.cpp,v 1.4 2002/01/11 14:35:03 tksuoran Exp $
*/


#include "Teddy/SysSupport/EndianIn.h"
#include "Teddy/SysSupport/Exception.h"


namespace Teddy      {
namespace SysSupport {


    EndianIn::EndianIn( const std::string &file_name ){
    open( file_name );
}


EndianIn::~EndianIn(){
    close();
}


void EndianIn::open( const std::string &file_name ){
    ifs = new ifstream( file_name.c_str(), ios::in|ios::binary );
    /*
    cout << "Opened file " << file_name;
    cout << " for reading. Handle " << (long)ifs;
    cout << " Good status " << ifs->good();
    cout << " Is Open " << ifs->is_open();
    cout << " tellg " << ifs->tellg();
    cout << endl;
    if( ifs->tellg()!=0 ){
        cout << "Hmm, seems like we are not at the beginning of the stream. Rewinding." << endl;
        ifs->seekg(0,ios::beg);
        cout << "Final tellg " << ifs->tellg() << endl;
    }
    */
}


void EndianIn::close(){
    //cout << "Closing file at pos " << ifs->tellg() << endl;
    if( ifs != NULL ){
        ifs->close(), ifs = NULL;
        delete ifs;
        ifs = NULL;
    }
}


unsigned long EndianIn::len(){
    streampos original = ifs->tellg();
    ifs->seekg( 0, ios::end );
    unsigned long l = ifs->tellg();
    ifs->seekg( original, ios::beg );
    return l;
}


void EndianIn::read_all( char *buf ){
    ifs->read( buf, len() );
}


unsigned char EndianIn::read_byte(){
    int            C;
    unsigned char  c = 0;

    C = ifs->get();
    if( C == EOF ){
        throw( Exception("EOF read error") );
    }else{
        c = (unsigned char)C;
    }
    return c;
}


unsigned short int EndianIn::read_short(){
    unsigned char c1, c2;

    c1 = read_byte();
    c2 = read_byte();

    if( q_MSBfirst() ){
        return (c1 << 8) | c2;
    }else{
        return (c2 << 8) | c1;
    }
}


unsigned long int EndianIn::read_long(){
    unsigned char c1, c2, c3, c4;

    c1 = read_byte();
    c2 = read_byte();
    c3 = read_byte();
    c4 = read_byte();   

    if ( q_MSBfirst() ){
        return (c1 << 24) | (c2 << 16) | (c3 << 8) | c4;
    }else{
        return (c4 << 24) | (c3 << 16) | (c2 << 8) | c1;
    }
}


float EndianIn::read_float(){
    float          ret_val;
    long          *shadow = (long*)(&ret_val);
    unsigned char  c1, c2, c3, c4;

    c1 = read_byte();
    c2 = read_byte();
    c3 = read_byte();
    c4 = read_byte();   

    if ( q_MSBfirst() ){
        *shadow = (c1 << 24) | (c2 << 16) | (c3 << 8) | c4;
    }else{
        *shadow = (c4 << 24) | (c3 << 16) | (c2 << 8) | c1;
    }

    return ret_val;
}


};  //  namespace SysSupport
};  //  namespace Teddy