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

#include "lapacke_utils.h"

lapack_int LAPACKE_chseqr_work( int matrix_layout, char job, char compz,
                                lapack_int n, lapack_int ilo, lapack_int ihi,
                                lapack_complex_float* h, lapack_int ldh,
                                lapack_complex_float* w,
                                lapack_complex_float* z, lapack_int ldz,
                                lapack_complex_float* work, lapack_int lwork )
{
    lapack_int info = 0;
    if( matrix_layout == LAPACK_COL_MAJOR ) {
        /* Call LAPACK function and adjust info */
        LAPACK_chseqr( &job, &compz, &n, &ilo, &ihi, h, &ldh, w, z, &ldz, work,
                       &lwork, &info );
        if( info < 0 ) {
            info = info - 1;
        }
    } else if( matrix_layout == LAPACK_ROW_MAJOR ) {
        lapack_int ldh_t = MAX(1,n);
        lapack_int ldz_t = MAX(1,n);
        lapack_complex_float* h_t = NULL;
        lapack_complex_float* z_t = NULL;
        /* Check leading dimension(s) */
        if( ldh < n ) {
            info = -8;
            LAPACKE_xerbla( "LAPACKE_chseqr_work", info );
            return info;
        }
        if( ldz < n ) {
            info = -11;
            LAPACKE_xerbla( "LAPACKE_chseqr_work", info );
            return info;
        }
        /* Query optimal working array(s) size if requested */
        if( lwork == -1 ) {
            LAPACK_chseqr( &job, &compz, &n, &ilo, &ihi, h, &ldh_t, w, z,
                           &ldz_t, work, &lwork, &info );
            return (info < 0) ? (info - 1) : info;
        }
        /* Allocate memory for temporary array(s) */
        h_t = (lapack_complex_float*)
            LAPACKE_malloc( sizeof(lapack_complex_float) * ldh_t * MAX(1,n) );
        if( h_t == NULL ) {
            info = LAPACK_TRANSPOSE_MEMORY_ERROR;
            goto exit_level_0;
        }
        if( LAPACKE_lsame( compz, 'i' ) || LAPACKE_lsame( compz, 'v' ) ) {
            z_t = (lapack_complex_float*)
                LAPACKE_malloc( sizeof(lapack_complex_float) *
                                ldz_t * MAX(1,n) );
            if( z_t == NULL ) {
                info = LAPACK_TRANSPOSE_MEMORY_ERROR;
                goto exit_level_1;
            }
        }
        /* Transpose input matrices */
        LAPACKE_cge_trans( matrix_layout, n, n, h, ldh, h_t, ldh_t );
        if( LAPACKE_lsame( compz, 'v' ) ) {
            LAPACKE_cge_trans( matrix_layout, n, n, z, ldz, z_t, ldz_t );
        }
        /* Call LAPACK function and adjust info */
        LAPACK_chseqr( &job, &compz, &n, &ilo, &ihi, h_t, &ldh_t, w, z_t,
                       &ldz_t, work, &lwork, &info );
        if( info < 0 ) {
            info = info - 1;
        }
        /* Transpose output matrices */
        LAPACKE_cge_trans( LAPACK_COL_MAJOR, n, n, h_t, ldh_t, h, ldh );
        if( LAPACKE_lsame( compz, 'i' ) || LAPACKE_lsame( compz, 'v' ) ) {
            LAPACKE_cge_trans( LAPACK_COL_MAJOR, n, n, z_t, ldz_t, z, ldz );
        }
        /* Release memory and exit */
        if( LAPACKE_lsame( compz, 'i' ) || LAPACKE_lsame( compz, 'v' ) ) {
            LAPACKE_free( z_t );
        }
exit_level_1:
        LAPACKE_free( h_t );
exit_level_0:
        if( info == LAPACK_TRANSPOSE_MEMORY_ERROR ) {
            LAPACKE_xerbla( "LAPACKE_chseqr_work", info );
        }
    } else {
        info = -1;
        LAPACKE_xerbla( "LAPACKE_chseqr_work", info );
    }
    return info;
}
