memblk.h

高效的c++科学算法库

#ifndef SL_MATRIX_MEMORY_MEMBLK_H
#define SL_MATRIX_MEMORY_MEMBLK_H

/*
 ******************************
 * Scientific Library (GNU Public Licence)
 *
 * Author: Laurent Deniau, [e-mail]
 *
 * $Id: memblk.h,v 1.2 1998/11/12 16:17:36 paubert Exp $
 *
 * Suggestions: [e-mail]
 * Bugs:   [e-mail]
 *
 * For more information, please see the sl++ Home Page:
 * http://wwwinfo.cern.ch/~ldeniau/sl.html
 *
 ******************************
 */

#ifndef SL_MATRIX_MEMORY_H
#error <sl/matrix/memblk.h> must be included via <sl/matrix/memory.h>
#endif

#ifdef HAVE_NAMESPACE
namespace sl 
{
#endif




    template <typename T_value>
        class MemBlock {


          public:

        typedef T_value value_t;

        T_value * base () const { return my_b; }
        T_value const* const_base () const { return my_b; }


          protected:

        Bool isOwner () const { return my_o == this; }


          protected:

        explicit
            MemBlock ()
            : my_b ( 0 ), my_o ( this ) {
        }

        explicit
            MemBlock (size_t const n)
            : my_b ( new T_value[n] ), my_o ( this ) {
#ifdef SL_DEBUG_TRACE_MEMORY_ALLOCATIONS
            cerr << "MemBlock: allocation of " << n << " elements "
                 << '[' << n * sizeof(T_value) << " bytes] to " << this << endl;
#endif
        }
    
        explicit
            MemBlock (T_value* const memzone)
            : my_b ( memzone ), my_o ( 0 ) {
        }

          // WARNING: Do NOT declare the copy constructor !
  

          public:

        ~MemBlock () {
            if ( isOwner() ) {
                delete [] my_b;
#ifdef SL_DEBUG_TRACE_MEMORY_ALLOCATIONS
                cerr << "MemBlock: deletion of elements of " << this << endl;
#endif
            }
        }
  

          protected:

        template <typename T2_value>
            void
            set (size_t const n, T2_value const x) {
            for(size_t i=0;i<n;i++)
                my_b[i] = x;
        }

        template <typename T2_value>
            void
            copy (size_t const n, T2_value const* t) {
            for(size_t i=0;i<n;i++)
                my_b[i] = t[i];
        }

        void
            newBlock (size_t const n) {
            assert ( isOwner() );
            my_b = n ? new T_value[n] : 0;
#ifdef SL_DEBUG_TRACE_MEMORY_ALLOCATIONS
            cerr << "MemBlock: allocation of " << n << " elements "
                 << '[' << n * sizeof(T_value) << " bytes] to " << this << endl;
#endif
        }
  
        void
            resize (size_t const n) {
            delete [] my_b;
            newBlock(n);
        }

        void
            reshape (size_t const old_n, size_t const new_n) {
            T_value const* const t = my_b;
            newBlock(new_n);
            copy(min(old_n, new_n), t);
            delete [] t;
        }


          private:

        T_value* my_b;          // base pointer to the data
        void const* const my_o; // owner of the data (this)
    };

#ifdef HAVE_NAMESPACE
}
#endif 

#endif
// SL_MATRIX_MEMORY_MEMBLK_H