/*
This file is part of the netCDF Fortran 77 API.

This file handles the the conversion of vecors from fortran to C.

Copyright 2006, University Corporation for Atmospheric Research. See
the COPYRIGHT file for copying and redistribution conditions.

$Id: fort-lib.c,v 1.6 2006/08/16 03:56:58 ed Exp $
*/

#include <config.h>
#include <stddef.h>	/* for NULL */
#include <errno.h>

#include "netcdf.h"
#include "ncfortran.h"
#include "fort-lib.h"


/*
 * Convert a C dimension-ID vector into a FORTRAN dimension-ID vector.
 */
NF_INTEGER*
c2f_dimids(int ncid, int varid, const int* cdimids, NF_INTEGER* fdimids)
{
    int	i;
    int	ndims;

    if (nc_inq_varndims(ncid, varid, &ndims) != 0)
	return NULL;

    for (i = 0; i < ndims; ++i)
	fdimids[ndims - 1 - i] = cdimids[i] + 1;

    return fdimids;
}


/*
 * Convert a FORTRAN dimension-ID vector into a C dimension-ID vector.
 */
int*
f2c_dimids(int ndims, const NF_INTEGER* fdimids, int* cdimids)
{
    int	i;

    for (i = 0; i < ndims; ++i)
	cdimids[i] = fdimids[ndims - 1 - i] - 1;

    return cdimids;
}


/*
 * Convert FORTRAN co-ordinates into C co-ordinates.
 */
size_t*
f2c_coords(int ncid, int varid, const NF_INTEGER* fcoords,
    size_t* ccoords)
{
    int	i;
    int	ndims;

    if (nc_inq_varndims(ncid, varid, &ndims) != 0)
	return NULL;

    for (i = 0; i < ndims; ++i)
	ccoords[i] = fcoords[ndims - 1 - i] - 1;

    return ccoords;
}


/*
 * Convert FORTRAN counts into C counts.
 */
size_t*
f2c_counts(int ncid, int varid, const NF_INTEGER* fcounts,
    size_t* ccounts)
{
    int	i;
    int	ndims;

    if (nc_inq_varndims(ncid, varid, &ndims) != 0)
	return NULL;

    for (i = 0; i < ndims; ++i)
	ccounts[i] = fcounts[ndims - 1 - i];

    return ccounts;
}


/*
 * Convert FORTRAN strides into C strides.
 *
 * Helper function.
 */
ptrdiff_t*
f2c_strides(int ncid, int varid, const NF_INTEGER* fstrides,
    ptrdiff_t* cstrides)
{
    int	i;
    int	ndims;

    if (nc_inq_varndims(ncid, varid, &ndims) != 0)
	return NULL;

    for (i = 0; i < ndims; ++i)
	cstrides[i] = fstrides[ndims - 1 - i];

    return cstrides;
}


/*
 * Convert a FORTRAN mapping vector into a C mapping vector.
 */
ptrdiff_t*
f2c_maps(int ncid, int varid, const NF_INTEGER* fmaps, ptrdiff_t* cmaps)
{
    return f2c_strides(ncid, varid, fmaps, cmaps);
}