hashtables.h

Go to the documentation of this file.

/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2012 SoftPLC Corporation, Dick Hollenbeck <dick@softplc.com>
 * Copyright (C) 2012-2020 KiCad Developers, see CHANGELOG.TXT for contributors.
 *
 * 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 2
 * 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, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */

#ifndef HASHTABLES_H_
#define HASHTABLES_H_

#include <eda_item.h>
#include <wx/string.h>

// Two competing strategies for providing portable hashtables are given:
// std C++ and boost.

// First some utility classes and functions common to both strategies.

struct iequal_to : std::binary_function< const char*, const char*, bool >
{
    bool operator()( const char* x, const char* y ) const
    {
        return !strcmp( x, y );
    }
};


struct fnv_1a
{
    /* not used, std::string is too slow:
    std::size_t operator()( std::string const& text ) const
    {
        std::size_t hash = 2166136261u;

        for( std::string::const_iterator it = text.begin(), end = text.end();
                it != end;  ++it )
        {
            hash ^= *it;
            hash *= 16777619;
        }
        return hash;
    }
    */

    std::size_t operator()( const char* it ) const
    {
        std::size_t hash = 2166136261u;

        for( ; *it;  ++it )
        {
            hash ^= (unsigned char) *it;
            hash *= 16777619;
        }
        return hash;
    }
};


struct WXSTRING_HASH : std::unary_function<wxString, std::size_t>
{
    std::size_t operator()( const wxString& aString ) const
    {
        std::size_t hash = 2166136261u;

        for( wxString::const_iterator it = aString.begin(); it != aString.end(); ++it )
        {
            unsigned ch = static_cast<unsigned>( *it );
            hash ^= ch;
            hash *= 16777619;
        }
        return hash;
    }
};


class NETINFO_ITEM;


#if 1   // C++ std::unordered_map, trying it now

#include <unordered_map>


#ifdef SWIG
#define DECL_HASH_FOR_SWIG( TypeName, KeyType, ValueType )          \
    namespace std                                                   \
    {                                                               \
        % template( TypeName ) unordered_map<KeyType, ValueType>;   \
    }                                                               \
    typedef std::unordered_map<KeyType, ValueType> TypeName;
#else
#define DECL_HASH_FOR_SWIG( TypeName, KeyType, ValueType )          \
    typedef std::unordered_map<KeyType, ValueType> TypeName;
#endif


typedef std::unordered_map< const char*, int, fnv_1a, iequal_to > KEYWORD_MAP;

typedef std::unordered_map< std::string, EDA_RECT > RECT_MAP;


#elif 1     // boost::unordered_map

// fix a compile bug at line 97 of boost/detail/container_fwd.hpp
#define BOOST_DETAIL_TEST_FORCE_CONTAINER_FWD

#include <boost/unordered_map.hpp>

// see http://www.boost.org/doc/libs/1_49_0/doc/html/boost/unordered_map.html


typedef boost::unordered_map< const char*, int, fnv_1a, iequal_to >     KEYWORD_MAP;


typedef boost::unordered_map< std::string, EDA_RECT >  RECT_MAP;

typedef boost::unordered_map< const wxString, NETINFO_ITEM*, WXSTRING_HASH > NETNAMES_MAP;
typedef boost::unordered_map< const int, NETINFO_ITEM* > NETCODES_MAP;

#endif

#endif // HASHTABLES_H_