glib/glibmm/arrayhandle.h

#ifndef _GLIBMM_ARRAYHANDLE_H
#define _GLIBMM_ARRAYHANDLE_H

/* Copyright (C) 2002 The gtkmm Development Team
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

#include <glibmmconfig.h>
#include <glibmm/containerhandle_shared.h>

namespace Glib
{

namespace Container_Helpers
{

#ifndef DOXYGEN_SHOULD_SKIP_THIS

/* Count the number of elements in a 0-terminated sequence.
 */
template <class T>
inline std::size_t
compute_array_size(const T* array)
{
  const T* pend = array;

  while (*pend)
    ++pend;

  return (pend - array);
}

/* Allocate and fill a 0-terminated array.  The size argument
 * specifies the number of elements in the input sequence.
 */
template <class For, class Tr>
typename Tr::CType*
create_array(For pbegin, std::size_t size, Tr)
{
  using CType = typename Tr::CType;

  CType* const array = static_cast<CType*>(g_malloc((size + 1) * sizeof(CType)));
  CType* const array_end = array + size;

  for (CType* pdest = array; pdest != array_end; ++pdest)
  {
    // Use & to force a warning if the iterator returns a temporary object.
    *pdest = Tr::to_c_type(*&*pbegin);
    ++pbegin;
  }

  *array_end = CType();
  return array;
}

template <class For>
gboolean*
create_bool_array(For pbegin, std::size_t size)
{
  gboolean* const array(static_cast<gboolean*>(g_malloc((size + 1) * sizeof(gboolean))));
  gboolean* const array_end(array + size);

  for (gboolean* pdest(array); pdest != array_end; ++pdest)
  {
    *pdest = *pbegin;
    ++pbegin;
  }

  *array_end = false;
  return array;
}

/* Convert from any container that supports forward
 * iterators and has a size() method.
 */
template <class Tr, class Cont>
struct ArraySourceTraits
{
  using CType = typename Tr::CType;

  static std::size_t get_size(const Cont& cont) { return cont.size(); }

  static const CType* get_data(const Cont& cont, std::size_t size)
  {
    return Glib::Container_Helpers::create_array(cont.begin(), size, Tr());
  }

  static const Glib::OwnershipType initial_ownership = Glib::OWNERSHIP_SHALLOW;
};

// source traits for bools.
template <class Cont>
struct BoolArraySourceTraits
{
  using CType = gboolean;

  static std::size_t get_size(const Cont& cont) { return cont.size(); }

  static const CType* get_data(const Cont& cont, std::size_t size)
  {
    return Glib::Container_Helpers::create_bool_array(cont.begin(), size);
  }

  static const Glib::OwnershipType initial_ownership = Glib::OWNERSHIP_SHALLOW;
};
/* Convert from a 0-terminated array.  The Cont argument must be a pointer
 * to the first element.  Note that only arrays of the C type are supported.
 */
template <class Tr, class Cont>
struct ArraySourceTraits<Tr, Cont*>
{
  using CType = typename Tr::CType;

  static std::size_t get_size(const CType* array)
  {
    return (array) ? Glib::Container_Helpers::compute_array_size(array) : 0;
  }

  static const CType* get_data(const CType* array, std::size_t) { return array; }

  static const Glib::OwnershipType initial_ownership = Glib::OWNERSHIP_NONE;
};

template <class Tr, class Cont>
struct ArraySourceTraits<Tr, const Cont*> : ArraySourceTraits<Tr, Cont*>
{
};

/* Convert from a 0-terminated array.  The Cont argument must be a pointer
 * to the first element.  Note that only arrays of the C type are supported.
 * For consistency, the array must be 0-terminated, even though the array
 * size is known at compile time.
 */
template <class Tr, class Cont, std::size_t N>
struct ArraySourceTraits<Tr, Cont[N]>
{
  using CType = typename Tr::CType;

  static std::size_t get_size(const CType*) { return (N - 1); }

  static const CType* get_data(const CType* array, std::size_t) { return array; }

  static const Glib::OwnershipType initial_ownership = Glib::OWNERSHIP_NONE;
};

template <class Tr, class Cont, std::size_t N>
struct ArraySourceTraits<Tr, const Cont[N]> : ArraySourceTraits<Tr, Cont[N]>
{
};

#endif /* DOXYGEN_SHOULD_SKIP_THIS */

/**
 * @ingroup ContHelpers
 */
template <class Tr>
class ArrayHandleIterator
{
public:
  using CppType = typename Tr::CppType;
  using CType = typename Tr::CType;

  using iterator_category = std::random_access_iterator_tag;
  using value_type = CppType;
  using difference_type = std::ptrdiff_t;
  using reference = value_type;
  using pointer = void;

  explicit inline ArrayHandleIterator(const CType* pos);

  inline value_type operator*() const;
  inline value_type operator[](difference_type offset) const;

  inline ArrayHandleIterator<Tr>& operator++();
  inline const ArrayHandleIterator<Tr> operator++(int);
  // these are needed by msvc 2005 when using deque.
  inline ArrayHandleIterator<Tr>& operator--();
  inline const ArrayHandleIterator<Tr> operator--(int);

  // All this random access stuff is only there because STL algorithms
  // usually have optimized specializations for random access iterators,
  // and we don't want to give away efficiency for nothing.
  //
  inline ArrayHandleIterator<Tr>& operator+=(difference_type rhs);
  inline ArrayHandleIterator<Tr>& operator-=(difference_type rhs);
  inline const ArrayHandleIterator<Tr> operator+(difference_type rhs) const;
  inline const ArrayHandleIterator<Tr> operator-(difference_type rhs) const;
  inline difference_type operator-(const ArrayHandleIterator<Tr>& rhs) const;

  inline bool operator==(const ArrayHandleIterator<Tr>& rhs) const;
  inline bool operator!=(const ArrayHandleIterator<Tr>& rhs) const;
  inline bool operator<(const ArrayHandleIterator<Tr>& rhs) const;
  inline bool operator>(const ArrayHandleIterator<Tr>& rhs) const;
  inline bool operator<=(const ArrayHandleIterator<Tr>& rhs) const;
  inline bool operator>=(const ArrayHandleIterator<Tr>& rhs) const;

private:
  const CType* pos_;
};

} // namespace Container_Helpers

// TODO: When we can break ABI, remove this and replace uses of it with std::vector.
// We cannot deprecate it yet, because we cannot easily deprecate methods that use it
//- for instance, we cannot just override methods that use it as a return type.

/** This is an intermediate type. When a method takes this, or returns this, you
 * should use a standard C++ container of your choice, such as std::list or
 * std::vector.
 *
 * However, this is not used in new API. We now prefer to just use std::vector,
 * which is less flexibile, but makes the API clearer.
 *
 * @ingroup ContHandles
 */
template <class T, class Tr = Glib::Container_Helpers::TypeTraits<T>>
class ArrayHandle
{
public:
  using CppType = typename Tr::CppType;
  using CType = typename Tr::CType;

  using value_type = CppType;
  using size_type = std::size_t;
  using difference_type = std::ptrdiff_t;

  using const_iterator = Glib::Container_Helpers::ArrayHandleIterator<Tr>;
  using iterator = Glib::Container_Helpers::ArrayHandleIterator<Tr>;

  template <class Cont>
  inline ArrayHandle(const Cont& container);

  // Take over ownership of an array created by GTK+ functions.
  inline ArrayHandle(const CType* array, std::size_t array_size, Glib::OwnershipType ownership);
  inline ArrayHandle(const CType* array, Glib::OwnershipType ownership);

  // Copying clears the ownership flag of the source handle.
  inline ArrayHandle(const ArrayHandle<T, Tr>& other);

  ~ArrayHandle() noexcept;

  inline const_iterator begin() const;
  inline const_iterator end() const;

  template <class U>
  inline operator std::vector<U>() const;
  template <class U>
  inline operator std::deque<U>() const;
  template <class U>
  inline operator std::list<U>() const;

  template <class Cont>
  inline void assign_to(Cont& container) const;

  template <class Out>
  inline void copy(Out pdest) const;

  inline const CType* data() const;
  inline std::size_t size() const;
  inline bool empty() const;

private:
  std::size_t size_;
  const CType* parray_;
  mutable Glib::OwnershipType ownership_;

  // No copy assignment.
  ArrayHandle<T, Tr>& operator=(const ArrayHandle<T, Tr>&);
};

template <>
class GLIBMM_API ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>
{
public:
  using Me = ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>;
  using Tr = Container_Helpers::TypeTraits<bool>;

  using CppType = Tr::CppType;
  using CType = Tr::CType;

  using value_type = CppType;
  using size_type = std::size_t;
  using difference_type = std::ptrdiff_t;

  using const_iterator = Glib::Container_Helpers::ArrayHandleIterator<Tr>;
  using iterator = Glib::Container_Helpers::ArrayHandleIterator<Tr>;

  template <class Cont>
  inline ArrayHandle(const Cont& container);

  // Take over ownership of an array created by GTK+ functions.
  inline ArrayHandle(const CType* array, std::size_t array_size, Glib::OwnershipType ownership);
  inline ArrayHandle(const CType* array, Glib::OwnershipType ownership);

  // Copying clears the ownership flag of the source handle.
  inline ArrayHandle(const Me& other);

  ~ArrayHandle() noexcept;

  inline const_iterator begin() const;
  inline const_iterator end() const;

  // this is inside class definition, so msvc 2005, 2008 and 2010 can compile this code.
  template <class U>
  inline operator std::vector<U>() const
  {
#ifdef GLIBMM_HAVE_TEMPLATE_SEQUENCE_CTORS
    return std::vector<U>(this->begin(), this->end());
#else
    std::vector<U> temp;
    temp.reserve(this->size());
    Glib::Container_Helpers::fill_container(temp, this->begin(), this->end());
    return temp;
#endif
  }

  // this is inside class definition, so msvc 2005, 2008 and 2010 can compile this code.
  template <class U>
  inline operator std::deque<U>() const
  {
#ifdef GLIBMM_HAVE_TEMPLATE_SEQUENCE_CTORS
    return std::deque<U>(this->begin(), this->end());
#else
    std::deque<U> temp;
    Glib::Container_Helpers::fill_container(temp, this->begin(), this->end());
    return temp;
#endif
  }

  // this is inside class definition, so msvc 2005, 2008 and 2010 can compile this code.
  template <class U>
  inline operator std::list<U>() const
  {
#ifdef GLIBMM_HAVE_TEMPLATE_SEQUENCE_CTORS
    return std::list<U>(this->begin(), this->end());
#else
    std::list<U> temp;
    Glib::Container_Helpers::fill_container(temp, this->begin(), this->end());
    return temp;
#endif
  }

  template <class Cont>
  inline void assign_to(Cont& container) const;

  template <class Out>
  inline void copy(Out pdest) const;

  inline const CType* data() const;
  inline std::size_t size() const;
  inline bool empty() const;

private:
  std::size_t size_;
  const CType* parray_;
  mutable Glib::OwnershipType ownership_;

  // No copy assignment.
  Me& operator=(const Me&);
};

// TODO: Remove this when we can break glibmm API.
/** If a method takes this as an argument, or has this as a return type, then you can use a standard
 * container such as std::list<Glib::ustring> or std::vector<Glib::ustring>.
 *
 *
 * However, this is not used in new API. We now prefer to just use std::vector,
 * which is less flexibile, but makes the API clearer.
 *
 * @ingroup ContHandles
 */
using StringArrayHandle = ArrayHandle<Glib::ustring>;

/***************************************************************************/
/*  Inline implementation                                                  */
/***************************************************************************/

#ifndef DOXYGEN_SHOULD_SKIP_THIS

namespace Container_Helpers
{

/**** Glib::Container_Helpers::ArrayHandleIterator<> ***********************/

template <class Tr>
inline ArrayHandleIterator<Tr>::ArrayHandleIterator(const CType* pos) : pos_(pos)
{
}

template <class Tr>
inline typename ArrayHandleIterator<Tr>::value_type ArrayHandleIterator<Tr>::operator*() const
{
  return Tr::to_cpp_type(*pos_);
}

template <class Tr>
inline typename ArrayHandleIterator<Tr>::value_type ArrayHandleIterator<Tr>::operator[](
  difference_type offset) const
{
  return Tr::to_cpp_type(pos_[offset]);
}

template <class Tr>
inline ArrayHandleIterator<Tr>& ArrayHandleIterator<Tr>::operator++()
{
  ++pos_;
  return *this;
}

template <class Tr>
inline const ArrayHandleIterator<Tr> ArrayHandleIterator<Tr>::operator++(int)
{
  return ArrayHandleIterator<Tr>(pos_++);
}

template <class Tr>
inline ArrayHandleIterator<Tr>& ArrayHandleIterator<Tr>::operator--()
{
  --pos_;
  return *this;
}

template <class Tr>
inline const ArrayHandleIterator<Tr> ArrayHandleIterator<Tr>::operator--(int)
{
  return ArrayHandleIterator<Tr>(pos_--);
}

template <class Tr>
inline ArrayHandleIterator<Tr>&
ArrayHandleIterator<Tr>::operator+=(typename ArrayHandleIterator<Tr>::difference_type rhs)
{
  pos_ += rhs;
  return *this;
}

template <class Tr>
inline ArrayHandleIterator<Tr>&
ArrayHandleIterator<Tr>::operator-=(typename ArrayHandleIterator<Tr>::difference_type rhs)
{
  pos_ -= rhs;
  return *this;
}

template <class Tr>
inline const ArrayHandleIterator<Tr>
ArrayHandleIterator<Tr>::operator+(typename ArrayHandleIterator<Tr>::difference_type rhs) const
{
  return ArrayHandleIterator<Tr>(pos_ + rhs);
}

template <class Tr>
inline const ArrayHandleIterator<Tr>
ArrayHandleIterator<Tr>::operator-(typename ArrayHandleIterator<Tr>::difference_type rhs) const
{
  return ArrayHandleIterator<Tr>(pos_ - rhs);
}

template <class Tr>
inline typename ArrayHandleIterator<Tr>::difference_type
ArrayHandleIterator<Tr>::operator-(const ArrayHandleIterator<Tr>& rhs) const
{
  return (pos_ - rhs.pos_);
}

template <class Tr>
inline bool
ArrayHandleIterator<Tr>::operator==(const ArrayHandleIterator<Tr>& rhs) const
{
  return (pos_ == rhs.pos_);
}

template <class Tr>
inline bool
ArrayHandleIterator<Tr>::operator!=(const ArrayHandleIterator<Tr>& rhs) const
{
  return (pos_ != rhs.pos_);
}

template <class Tr>
inline bool
ArrayHandleIterator<Tr>::operator<(const ArrayHandleIterator<Tr>& rhs) const
{
  return (pos_ < rhs.pos_);
}

template <class Tr>
inline bool
ArrayHandleIterator<Tr>::operator>(const ArrayHandleIterator<Tr>& rhs) const
{
  return (pos_ > rhs.pos_);
}

template <class Tr>
inline bool
ArrayHandleIterator<Tr>::operator<=(const ArrayHandleIterator<Tr>& rhs) const
{
  return (pos_ <= rhs.pos_);
}

template <class Tr>
inline bool
ArrayHandleIterator<Tr>::operator>=(const ArrayHandleIterator<Tr>& rhs) const
{
  return (pos_ >= rhs.pos_);
}

} // namespace Container_Helpers

/**** Glib::ArrayHandle<> **************************************************/

template <class T, class Tr>
template <class Cont>
inline ArrayHandle<T, Tr>::ArrayHandle(const Cont& container)
: size_(Glib::Container_Helpers::ArraySourceTraits<Tr, Cont>::get_size(container)),
  parray_(Glib::Container_Helpers::ArraySourceTraits<Tr, Cont>::get_data(container, size_)),
  ownership_(Glib::Container_Helpers::ArraySourceTraits<Tr, Cont>::initial_ownership)
{
}

template <class T, class Tr>
inline ArrayHandle<T, Tr>::ArrayHandle(const typename ArrayHandle<T, Tr>::CType* array,
  std::size_t array_size, Glib::OwnershipType ownership)
: size_((array) ? array_size : 0), parray_(array), ownership_(ownership)
{
}

template <class T, class Tr>
inline ArrayHandle<T, Tr>::ArrayHandle(
  const typename ArrayHandle<T, Tr>::CType* array, Glib::OwnershipType ownership)
: size_((array) ? Glib::Container_Helpers::compute_array_size(array) : 0),
  parray_(array),
  ownership_(ownership)
{
}

template <class T, class Tr>
inline ArrayHandle<T, Tr>::ArrayHandle(const ArrayHandle<T, Tr>& other)
: size_(other.size_), parray_(other.parray_), ownership_(other.ownership_)
{
  other.ownership_ = Glib::OWNERSHIP_NONE;
}

template <class T, class Tr>
ArrayHandle<T, Tr>::~ArrayHandle() noexcept
{
  if (parray_ && ownership_ != Glib::OWNERSHIP_NONE)
  {
    if (ownership_ != Glib::OWNERSHIP_SHALLOW)
    {
      // Deep ownership: release each container element.
      const CType* const pend = parray_ + size_;
      for (const CType* p = parray_; p != pend; ++p)
        Tr::release_c_type(*p);
    }
    g_free(const_cast<CType*>(parray_));
  }
}

template <class T, class Tr>
inline typename ArrayHandle<T, Tr>::const_iterator
ArrayHandle<T, Tr>::begin() const
{
  return Glib::Container_Helpers::ArrayHandleIterator<Tr>(parray_);
}

template <class T, class Tr>
inline typename ArrayHandle<T, Tr>::const_iterator
ArrayHandle<T, Tr>::end() const
{
  return Glib::Container_Helpers::ArrayHandleIterator<Tr>(parray_ + size_);
}

template <class T, class Tr>
template <class U>
inline ArrayHandle<T, Tr>::operator std::vector<U>() const
{
#ifdef GLIBMM_HAVE_TEMPLATE_SEQUENCE_CTORS
  return std::vector<U>(this->begin(), this->end());
#else
  std::vector<U> temp;
  temp.reserve(this->size());
  Glib::Container_Helpers::fill_container(temp, this->begin(), this->end());
  return temp;
#endif
}

template <class T, class Tr>
template <class U>
inline ArrayHandle<T, Tr>::operator std::deque<U>() const
{
#ifdef GLIBMM_HAVE_TEMPLATE_SEQUENCE_CTORS
  return std::deque<U>(this->begin(), this->end());
#else
  std::deque<U> temp;
  Glib::Container_Helpers::fill_container(temp, this->begin(), this->end());
  return temp;
#endif
}

template <class T, class Tr>
template <class U>
inline ArrayHandle<T, Tr>::operator std::list<U>() const
{
#ifdef GLIBMM_HAVE_TEMPLATE_SEQUENCE_CTORS
  return std::list<U>(this->begin(), this->end());
#else
  std::list<U> temp;
  Glib::Container_Helpers::fill_container(temp, this->begin(), this->end());
  return temp;
#endif
}

template <class T, class Tr>
template <class Cont>
inline void
ArrayHandle<T, Tr>::assign_to(Cont& container) const
{
#ifdef GLIBMM_HAVE_TEMPLATE_SEQUENCE_CTORS
  container.assign(this->begin(), this->end());
#else
  Cont temp;
  Glib::Container_Helpers::fill_container(temp, this->begin(), this->end());
  container.swap(temp);
#endif
}

template <class T, class Tr>
template <class Out>
inline void
ArrayHandle<T, Tr>::copy(Out pdest) const
{
  std::copy(this->begin(), this->end(), pdest);
}

template <class T, class Tr>
inline const typename ArrayHandle<T, Tr>::CType*
ArrayHandle<T, Tr>::data() const
{
  return parray_;
}

template <class T, class Tr>
inline std::size_t
ArrayHandle<T, Tr>::size() const
{
  return size_;
}

template <class T, class Tr>
inline bool
ArrayHandle<T, Tr>::empty() const
{
  return (size_ == 0);
}

/**** Glib::ArrayHandle<bool> **********************************************/

template <class Cont>
inline ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::ArrayHandle(const Cont& container)
: size_(Glib::Container_Helpers::BoolArraySourceTraits<Cont>::get_size(container)),
  parray_(Glib::Container_Helpers::BoolArraySourceTraits<Cont>::get_data(container, size_)),
  ownership_(Glib::Container_Helpers::BoolArraySourceTraits<Cont>::initial_ownership)
{
}

inline ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::ArrayHandle(
  const gboolean* array, std::size_t array_size, Glib::OwnershipType ownership)
: size_((array) ? array_size : 0), parray_(array), ownership_(ownership)
{
}

inline ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::ArrayHandle(
  const gboolean* array, Glib::OwnershipType ownership)
: size_((array) ? Glib::Container_Helpers::compute_array_size(array) : 0),
  parray_(array),
  ownership_(ownership)
{
}

inline ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::ArrayHandle(
  const ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>& other)
: size_(other.size_), parray_(other.parray_), ownership_(other.ownership_)
{
  other.ownership_ = Glib::OWNERSHIP_NONE;
}

inline ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::const_iterator
ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::begin() const
{
  return Glib::Container_Helpers::ArrayHandleIterator<Tr>(parray_);
}

inline ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::const_iterator
ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::end() const
{
  return Glib::Container_Helpers::ArrayHandleIterator<Tr>(parray_ + size_);
}

template <class Cont>
inline void
ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::assign_to(Cont& container) const
{
#ifdef GLIBMM_HAVE_TEMPLATE_SEQUENCE_CTORS
  container.assign(this->begin(), this->end());
#else
  Cont temp;
  Glib::Container_Helpers::fill_container(temp, this->begin(), this->end());
  container.swap(temp);
#endif
}

template <class Out>
inline void
ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::copy(Out pdest) const
{
  std::copy(this->begin(), this->end(), pdest);
}

inline const gboolean*
ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::data() const
{
  return parray_;
}

inline std::size_t
ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::size() const
{
  return size_;
}

inline bool
ArrayHandle<bool, Container_Helpers::TypeTraits<bool>>::empty() const
{
  return (size_ == 0);
}

#endif /* DOXYGEN_SHOULD_SKIP_THIS */

} // namespace Glib

#endif /* _GLIBMM_ARRAYHANDLE_H */