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// This file is part of the ustl library, an STL implementation.
//
// Copyright (C) 2005 by Mike Sharov <msharov@users.sourceforge.net>
// This file is free software, distributed under the MIT License.
//
// memblock.h
//

#ifndef MEMBLOCK_H_7ED63A891164CC43578E63664D52A196
#define MEMBLOCK_H_7ED63A891164CC43578E63664D52A196

#include "memlink.h"

namespace ustl {

/// \class memblock memblock.h ustl.h
/// \ingroup MemoryManagement
///
/// \brief Allocated memory block.
///
/// Adds memory management capabilities to memlink. Uses malloc and realloc to
/// maintain the internal pointer, but only if allocated using members of this class,
/// or if linked to using the Manage() member function. Managed memory is automatically
/// freed in the destructor.
///
class memblock : public memlink {
public:
    static const size_type	c_PageSize = 64;	///< The default minimum allocation unit.
public:
				memblock (void);
				memblock (const void* p, size_type n);
    explicit			memblock (size_type n);
    explicit			memblock (const cmemlink& b);
    explicit			memblock (const memlink& b);
				memblock (const memblock& b);
    virtual		       ~memblock (void);
    virtual void		unlink (void);
    inline void			assign (const cmemlink& l)	{ assign (l.cdata(), l.readable_size()); }
    inline const memblock&	operator= (const cmemlink& l)	{ assign (l); return (*this); }
    inline const memblock&	operator= (const memlink& l)	{ assign (l); return (*this); }
    inline const memblock&	operator= (const memblock& l)	{ assign (l); return (*this); }
    void			assign (const void* p, size_type n);
    void			swap (memblock& l);
    void			reserve (size_type newSize, bool bExact = true);
    void			resize (size_type newSize, bool bExact = true);
    iterator			insert (iterator start, size_type size);
    iterator			erase (iterator start, size_type size);
    inline void			clear (void)			{ resize (0); }
    inline bool			is_linked (void) const		{ return (!m_Capacity && cdata()); }
    inline size_type		max_size (void) const		{ return (is_linked() ? memlink::max_size() : SIZE_MAX); }
    inline size_type		capacity (void) const		{ return (m_Capacity); }
    inline void			manage (memlink& l)		{ manage (l.begin(), l.size()); }
    void			deallocate (void) throw();
    void			manage (void* p, size_type n);
    void			copy_link (void);
    void			read (istream& is);
    void			read_file (const char* filename);
protected:
    inline virtual size_type	minimumFreeCapacity (void) const { return (0); }
private:
    size_type			m_Capacity;	///< Number of bytes allocated by Resize.
};

/// Reads object \p l from stream \p is
inline istream& operator>> (istream& is, memblock& l)
{
    l.read (is);
    return (is);
}

} // namespace ustl

#endif