libcruft-util/types.hpp

188 lines
5.1 KiB
C++

/*
* This file is part of libgim.
*
* libgim 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.
*
* libgim 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 libgim. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2011 Danny Robson <danny@nerdcruft.net>
*/
#ifndef __TYPES_HPP
#define __TYPES_HPP
#include "annotations.hpp"
#include "debug.hpp"
#include "enable_if.hpp"
#include <cstdint>
#include <string>
#include <limits>
#include <memory>
template <int BITS>
struct bits_type;
template <> struct bits_type< 8> {
static const bool has_floating = false;
typedef uint8_t uint;
typedef int8_t sint;
typedef uint8_t floating;
};
template <> struct bits_type<16> {
static const bool has_floating = false;
typedef uint16_t uint;
typedef int16_t sint;
typedef uint16_t floating;
};
template <> struct bits_type<32> {
static const bool has_floating = true;
typedef uint32_t uint;
typedef int32_t sint;
typedef float floating;
};
template <> struct bits_type<64> {
static const bool has_floating = true;
typedef uint64_t uint;
typedef int64_t sint;
typedef double floating;
};
template <typename T>
struct sized_type : public bits_type<sizeof(T) * 8>
{ };
template <typename T>
std::string
type_to_string (void);
namespace detail {
template <typename T, typename V>
T
_sign_cast (const typename enable_if<sizeof(T) == sizeof(V) &&
std::is_unsigned<T>::value &&
std::is_signed<V>::value, V>::type v)
{
CHECK_HARD (v >= 0);
return static_cast<T> (v);
}
template <typename T, typename V>
T
_sign_cast (const typename enable_if<sizeof(T) == sizeof(V) &&
std::is_signed<T>::value &&
std::is_unsigned<V>::value, V>::type v)
{
CHECK_HARD (v < std::numeric_limits<V>::max () / 2);
return static_cast<T> (v);
}
}
/// Safely cast a numeric type to its (un)signed counterpart, aborting if the
/// dynamically checked result is not representable. May be optimised out if
/// NDEBUG is defined.
template <typename T, typename V>
T
sign_cast (const V v)
{ return detail::_sign_cast<T,V>(v); }
namespace detail {
// Same sign, no possibility of truncation with larger target type
template <typename T, typename V>
T
_trunc_cast (const typename enable_if<sizeof (T) >= sizeof (V) &&
std::is_signed<T>::value == std::is_signed<V>::value, V>::type v)
{ return v; }
template <typename T, typename V>
T
_trunc_cast (const typename enable_if<sizeof (T) < sizeof (V) &&
std::is_signed<T>::value == std::is_signed<V>::value, V>::type v) {
CHECK_HARD (v <= std::numeric_limits<T>::max ());
checK_hard (v >= std::numeric_limits<T>::min ());
return static_cast<T> (v);
}
}
template <typename T, typename V>
T
trunc_cast (V v)
{ return detail::_trunc_cast<T, V> (v); }
/// Returns the number of elements of a statically allocated array
template <typename T, size_t N>
size_t elems(T (&)[N])
{ return N; }
template<class T, class...Args>
std::unique_ptr<T> make_unique(Args&&... args) {
return std::unique_ptr<T> (new T(std::forward<Args>(args)...));
}
struct fourcc {
uint8_t data[4];
static fourcc from_str(const char[4]);
static fourcc from_chars(uint8_t, uint8_t, uint8_t, uint8_t);
bool operator== (const char[4]) const;
operator uint32_t (void) const;
};
std::ostream& operator<< (std::ostream&, fourcc);
template <typename T> struct is_dereferencable : std::false_type { };
template <typename T> struct is_dereferencable<T*> : std::true_type { };
template <typename T> struct is_dereferencable<std::unique_ptr<T>> : std::true_type { };
template <typename T> struct is_dereferencable<std::shared_ptr<T>> : std::true_type { };
template <typename T> struct is_dereferencable<std::weak_ptr<T>> : std::true_type { };
template <typename T> struct is_dereferencable<std::auto_ptr<T>> : std::true_type { };
template <typename T> struct dereferenced_type {
typedef typename std::enable_if<
std::is_pointer<T>::value,
std::remove_pointer<T>
>::type type;
};
template <typename T> struct dereferenced_type<std::unique_ptr<T>> { typedef T type; };
template <typename T> struct dereferenced_type<std::shared_ptr<T>> { typedef T type; };
template <typename T> struct dereferenced_type<std::weak_ptr<T>> { typedef T type; };
template <typename T> struct dereferenced_type<std::auto_ptr<T>> { typedef T type; };
#endif // __TYPES_HPP