hashtables.h

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/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2012 SoftPLC Corporation, Dick Hollenbeck <[email protected]>
 * Copyright The KiCad Developers, see AUTHORS.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, see <https://www.gnu.org/licenses/>.
 */
 
#ifndef HASHTABLES_H_
#define HASHTABLES_H_
 
#include <cstddef>
#include <unordered_map>
 
#include <wx/string.h>
 
// First some utility classes and functions
 

inline std::size_t KiHashCombine( std::size_t aSeed, std::size_t aValue )
{
    return aSeed ^ ( aValue + 0x9e3779b9 + ( aSeed << 6 ) + ( aSeed >> 2 ) );
}

struct iequal_to
{
    bool operator()( const char* x, const char* y ) const
    {
        return !strcmp( x, y );
    }
};
 

struct fnv_1a
{
    std::size_t operator()( const char* it ) const
    {
        std::size_t hash = 2166136261u;
 
        for( ; *it; ++it )
        {
            hash ^= (unsigned char) *it;
            hash *= 16777619;
        }
        return hash;
    }
};
 

typedef std::unordered_map< const char*, int, fnv_1a, iequal_to > KEYWORD_MAP;
 
 
#endif // HASHTABLES_H_