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*****************************************************************************
* Contents: Native middle-level C interface to LAPACK function dbdsqr
* Author: Intel Corporation
*****************************************************************************/

#include "lapacke_utils.h"

lapack_int LAPACKE_dbdsqr_work( int matrix_layout, char uplo, lapack_int n,
                                lapack_int ncvt, lapack_int nru, lapack_int ncc,
                                double* d, double* e, double* vt,
                                lapack_int ldvt, double* u, lapack_int ldu,
                                double* c, lapack_int ldc, double* work )
{
    lapack_int info = 0;
    if( matrix_layout == LAPACK_COL_MAJOR ) {
        /* Call LAPACK function and adjust info */
        LAPACK_dbdsqr( &uplo, &n, &ncvt, &nru, &ncc, d, e, vt, &ldvt, u, &ldu,
                       c, &ldc, work, &info );
        if( info < 0 ) {
            info = info - 1;
        }
    } else if( matrix_layout == LAPACK_ROW_MAJOR ) {
        lapack_int ldc_t = MAX(1,n);
        lapack_int ldu_t = MAX(1,nru);
        lapack_int ldvt_t = MAX(1,n);
        double* vt_t = NULL;
        double* u_t = NULL;
        double* c_t = NULL;
        /* Check leading dimension(s) */
        if( ldc < ncc ) {
            info = -14;
            LAPACKE_xerbla( "LAPACKE_dbdsqr_work", info );
            return info;
        }
        if( ldu < n ) {
            info = -12;
            LAPACKE_xerbla( "LAPACKE_dbdsqr_work", info );
            return info;
        }
        if( ldvt < ncvt ) {
            info = -10;
            LAPACKE_xerbla( "LAPACKE_dbdsqr_work", info );
            return info;
        }
        /* Allocate memory for temporary array(s) */
        if( ncvt != 0 ) {
            vt_t = (double*)
                LAPACKE_malloc( sizeof(double) * ldvt_t * MAX(1,ncvt) );
            if( vt_t == NULL ) {
                info = LAPACK_TRANSPOSE_MEMORY_ERROR;
                goto exit_level_0;
            }
        }
        if( nru != 0 ) {
            u_t = (double*)LAPACKE_malloc( sizeof(double) * ldu_t * MAX(1,n) );
            if( u_t == NULL ) {
                info = LAPACK_TRANSPOSE_MEMORY_ERROR;
                goto exit_level_1;
            }
        }
        if( ncc != 0 ) {
            c_t = (double*)
                LAPACKE_malloc( sizeof(double) * ldc_t * MAX(1,ncc) );
            if( c_t == NULL ) {
                info = LAPACK_TRANSPOSE_MEMORY_ERROR;
                goto exit_level_2;
            }
        }
        /* Transpose input matrices */
        if( ncvt != 0 ) {
            LAPACKE_dge_trans( matrix_layout, n, ncvt, vt, ldvt, vt_t, ldvt_t );
        }
        if( nru != 0 ) {
            LAPACKE_dge_trans( matrix_layout, nru, n, u, ldu, u_t, ldu_t );
        }
        if( ncc != 0 ) {
            LAPACKE_dge_trans( matrix_layout, n, ncc, c, ldc, c_t, ldc_t );
        }
        /* Call LAPACK function and adjust info */
        LAPACK_dbdsqr( &uplo, &n, &ncvt, &nru, &ncc, d, e, vt_t, &ldvt_t, u_t,
                       &ldu_t, c_t, &ldc_t, work, &info );
        if( info < 0 ) {
            info = info - 1;
        }
        /* Transpose output matrices */
        if( ncvt != 0 ) {
            LAPACKE_dge_trans( LAPACK_COL_MAJOR, n, ncvt, vt_t, ldvt_t, vt,
                               ldvt );
        }
        if( nru != 0 ) {
            LAPACKE_dge_trans( LAPACK_COL_MAJOR, nru, n, u_t, ldu_t, u, ldu );
        }
        if( ncc != 0 ) {
            LAPACKE_dge_trans( LAPACK_COL_MAJOR, n, ncc, c_t, ldc_t, c, ldc );
        }
        /* Release memory and exit */
        if( ncc != 0 ) {
            LAPACKE_free( c_t );
        }
exit_level_2:
        if( nru != 0 ) {
            LAPACKE_free( u_t );
        }
exit_level_1:
        if( ncvt != 0 ) {
            LAPACKE_free( vt_t );
        }
exit_level_0:
        if( info == LAPACK_TRANSPOSE_MEMORY_ERROR ) {
            LAPACKE_xerbla( "LAPACKE_dbdsqr_work", info );
        }
    } else {
        info = -1;
        LAPACKE_xerbla( "LAPACKE_dbdsqr_work", info );
    }
    return info;
}
