Function icvGoNextMemBlock

deps/opencv/modules/core/src/datastructs.cpp:208–262

Moves stack pointer to next block. If no blocks, allocate new one and link it to the storage: */

/* Moves stack pointer to next block.
   If no blocks, allocate new one and link it to the storage: */
static void
icvGoNextMemBlock( CvMemStorage * storage )
{
    if( !storage )
        CV_Error( CV_StsNullPtr, "" );

    if( !storage->top || !storage->top->next )
    {
        CvMemBlock *block;

        if( !(storage->parent) )
        {
            block = (CvMemBlock *)cvAlloc( storage->block_size );
        }
        else
        {
            CvMemStorage *parent = storage->parent;
            CvMemStoragePos parent_pos;

            cvSaveMemStoragePos( parent, &parent_pos );
            icvGoNextMemBlock( parent );

            block = parent->top;
            cvRestoreMemStoragePos( parent, &parent_pos );

            if( block == parent->top )  /* the single allocated block */
            {
                assert( parent->bottom == block );
                parent->top = parent->bottom = 0;
                parent->free_space = 0;
            }
            else
            {
                /* cut the block from the parent's list of blocks */
                parent->top->next = block->next;
                if( block->next )
                    block->next->prev = parent->top;
            }
        }

        /* link block */
        block->next = 0;
        block->prev = storage->top;

        if( storage->top )
            storage->top->next = block;
        else
            storage->top = storage->bottom = block;
    }

    if( storage->top->next )
        storage->top = storage->top->next;
    storage->free_space = storage->block_size - sizeof(CvMemBlock);
    assert( storage->free_space % CV_STRUCT_ALIGN == 0 );
}


/* Remember memory storage position: */