Function cvSeqPushFront

deps/opencv/modules/core/src/datastructs.cpp:1184–1214

Push element onto the front of the sequence: */

/* Push element onto the front of the sequence: */
CV_IMPL schar*
cvSeqPushFront( CvSeq *seq, const void *element )
{
    schar* ptr = 0;
    int elem_size;
    CvSeqBlock *block;

    if( !seq )
        CV_Error( CV_StsNullPtr, "" );

    elem_size = seq->elem_size;
    block = seq->first;

    if( !block || block->start_index == 0 )
    {
        icvGrowSeq( seq, 1 );

        block = seq->first;
        assert( block->start_index > 0 );
    }

    ptr = block->data -= elem_size;

    if( element )
        memcpy( ptr, element, elem_size );
    block->count++;
    block->start_index--;
    seq->total++;

    return ptr;
}


/* Shift out first element of the sequence: */