ArrayManager.hpp

Go to the documentation of this file.

#ifndef ARRAYMANAGER_HPP
#define ARRAYMANAGER_HPP

#include <cstdlib>

// Check the array size, and allocate the array if necessary.
// Free the array upon leaving scope unless KEEP_ARRAY
// is invoked.
#define ALLOC_CHECK_ARRAY( array, this_size )                                                                     \
    ArrayManager array##_manager( reinterpret_cast< void** >( array ), *( array##_allocated ), *( array##_size ), \
                                  this_size, sizeof( **( array ) ), err );                                        \
    if( iBase_SUCCESS != *err ) return

#define ALLOC_CHECK_TAG_ARRAY( array, this_size )                                                                 \
    ArrayManager array##_manager( reinterpret_cast< void** >( array ), *( array##_allocated ), *( array##_size ), \
                                  this_size, 1, err );                                                            \
    if( iBase_SUCCESS != *err ) return

#define KEEP_ARRAY( array ) array##_manager.keep_array()

// Check the array size, and allocate the array if necessary.
// Do NOT free the array upon leaving scope.
#define ALLOC_CHECK_ARRAY_NOFAIL( array, this_size ) \
    ALLOC_CHECK_ARRAY( array, this_size );           \
    KEEP_ARRAY( array )

// Implement RAII pattern for allocated arrays, stolen from iMesh
class ArrayManager
{
    void** arrayPtr;

  public:
    ArrayManager( void** array_ptr, int& array_allocated_space, int& array_size, int count, int val_size, int* err )
        : arrayPtr( 0 )
    {
        if( !*array_ptr || !array_allocated_space )
        {
            *array_ptr            = std::malloc( val_size * count );
            array_allocated_space = array_size = count;
            if( !*array_ptr )
            {
                *err = iBase_MEMORY_ALLOCATION_FAILED;
                return;
            }
            arrayPtr = array_ptr;
        }
        else
        {
            array_size = count;
            if( array_allocated_space < count )
            {
                *err = iBase_BAD_ARRAY_DIMENSION;
                return;
            }
        }

        *err = iBase_SUCCESS;
    }

    ~ArrayManager()
    {
        if( arrayPtr )
        {
            std::free( *arrayPtr );
            *arrayPtr = 0;
        }
    }

    void keep_array()
    {
        arrayPtr = 0;
    }
};

#endif