flags.h

// -*- mode: c++; tab-width: 4; indent-tabs-mode: t; c-file-style: "stroustrup"; -*-
// vi:set ts=4 sts=4 sw=4 noet :
// Copyright 20015 The TPIE development team
//
// This file is part of TPIE.
//
// TPIE 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 3 of the License, or (at your
// option) any later version.
//
// TPIE 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 TPIE.  If not, see <http://www.gnu.org/licenses/>
 
 
#ifndef _TPIE_FLAGS_H
#define _TPIE_FLAGS_H
 
#include <cstdint>
#include <tpie/serialization2.h>
 
namespace tpie {
namespace bits {
    
template <int S>
struct enum_storage_type_help {};
 
template <>
struct enum_storage_type_help<1> {typedef uint8_t type;};
 
template <>
struct enum_storage_type_help<2> {typedef uint16_t type;};
 
template <>
struct enum_storage_type_help<4> {typedef uint32_t type;};
 
template <>
struct enum_storage_type_help<8> {typedef uint64_t type;};
  
template <typename T>
struct enum_storage_type {
    typedef typename enum_storage_type_help<sizeof(T)>::type type;
};
} //namespace bits
 
template <typename T>
class flags {
private:
    typedef typename bits::enum_storage_type<T>::type st;
    typedef void (flags::*bool_type)() const;
    void bool_type_true() const {}
public:
    flags(): m_value(0) {}
    flags(T t): m_value(static_cast<st>(t)) {}
    friend flags operator|(const flags & l, const T & r) {return l | flags(r);}
    friend flags operator|(const flags & l, const flags & r) {return flags(l.m_value | r.m_value);}
    friend flags operator|(const T & l, const flags & r) {return flags(l) | r;}
    friend flags operator&(const flags & l, const flags & r) {return flags(l.m_value & r.m_value);}
    friend flags operator&(const T & l, const flags & r) {return flags(flags(l).m_value & r.m_value);}
    friend flags operator&(const flags & l, const T & r) {return flags(l.m_value & flags(r).m_value);}
    flags & operator|=(const T & r) { return *this |= flags(r); }
    flags & operator|=(const flags & r) { m_value |= r.m_value; return *this; }
    // See http://www.artima.com/cppsource/safebool2.html
    operator bool_type() const {return m_value?&flags::bool_type_true:NULL;}
    flags operator~() const {return flags(~m_value);}
    
    template <typename D>
    friend void serialize(D & dst, const flags<T> & f) {
        serialize(dst, f.m_value);
    }
 
    template <typename S>
    friend void unserialize(S & src, flags<T> & f) {
        unserialize(src, f.m_value);
    }
private:
    explicit flags(st value): m_value(value) {}
    st m_value;
};
 
#define TPIE_DECLARE_OPERATORS_FOR_FLAGS(T) \
inline tpie::flags<T> operator|(const T & l, const T & r) {return tpie::flags<T>(l) | r;} \
inline tpie::flags<T> operator~(const T & l) {return ~tpie::flags<T>(l);}
 
 
} //namespace tpie
 
#endif //#_TPIE_FLAGS_H