path: root/src/H5Tfloat.c

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by the Board of Trustees of the University of Illinois.         *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF5.  The full HDF5 copyright notice, including     *
 * terms governing use, modification, and redistribution, is contained in    *
 * the files COPYING and Copyright.html.  COPYING can be found at the root   *
 * of the source code distribution tree; Copyright.html can be found at the  *
 * root level of an installed copy of the electronic HDF5 document set and   *
 * is linked from the top-level documents page.  It can also be found at     *
 * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
 * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Module Info: This module contains the functionality for floating-point
 *      datatypes in the H5T interface.
 */

#define H5T_PACKAGE		/*suppress error about including H5Tpkg	  */

/* Interface initialization */
#define H5_INTERFACE_INIT_FUNC	H5T_init_float_interface

/* Pablo information */
/* (Put before include files to avoid problems with inline functions) */
#define PABLO_MASK	H5T_float_mask

#include "H5private.h"		/*generic functions			  */
#include "H5Eprivate.h"		/*error handling			  */
#include "H5Iprivate.h"		/*ID functions		   		  */
#include "H5Tpkg.h"		/*data-type functions			  */


/*--------------------------------------------------------------------------
NAME
   H5T_init_float_interface -- Initialize interface-specific information
USAGE
    herr_t H5T_init_float_interface()
   
RETURNS
    Non-negative on success/Negative on failure
DESCRIPTION
    Initializes any interface-specific data or routines.  (Just calls
    H5T_init_iterface currently).

--------------------------------------------------------------------------*/
static herr_t
H5T_init_float_interface(void)
{
    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5T_init_float_interface)

    FUNC_LEAVE_NOAPI(H5T_init())
} /* H5T_init_float_interface() */


/*-------------------------------------------------------------------------
 * Function:	H5Tget_fields
 *
 * Purpose:	Returns information about the locations of the various bit
 *		fields of a floating point datatype.  The field positions
 *		are bit positions in the significant region of the datatype.
 *		Bits are numbered with the least significant bit number zero.
 *
 *		Any (or even all) of the arguments can be null pointers.
 *
 * Return:	Success:	Non-negative, field locations and sizes are
 *				returned through the arguments.
 *
 *		Failure:	Negative
 *
 * Programmer:	Robb Matzke
 *		Wednesday, January  7, 1998
 *
 * Modifications:
 *	Robb Matzke, 22 Dec 1998
 *	Also works with derived datatypes.
 *-------------------------------------------------------------------------
 */
herr_t
H5Tget_fields(hid_t type_id, size_t *spos/*out*/,
	      size_t *epos/*out*/, size_t *esize/*out*/,
	      size_t *mpos/*out*/, size_t *msize/*out*/)
{
    H5T_t	*dt = NULL;
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_API(H5Tget_fields, FAIL)
    H5TRACE6("e","ixxxxx",type_id,spos,epos,esize,mpos,msize);

    /* Check args */
    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a datatype")
    while (dt->shared->parent)
        dt = dt->shared->parent; /*defer to parent*/
    if (H5T_FLOAT != dt->shared->type)
        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "operation not defined for datatype class")
    
    /* Get values */
    if (spos) *spos = dt->shared->u.atomic.u.f.sign;
    if (epos) *epos = dt->shared->u.atomic.u.f.epos;
    if (esize) *esize = dt->shared->u.atomic.u.f.esize;
    if (mpos) *mpos = dt->shared->u.atomic.u.f.mpos;
    if (msize) *msize = dt->shared->u.atomic.u.f.msize;

done:
    FUNC_LEAVE_API(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5Tset_fields
 *
 * Purpose:	Sets the locations and sizes of the various floating point
 *		bit fields.  The field positions are bit positions in the
 *		significant region of the datatype.  Bits are numbered with
 *		the least significant bit number zero.
 *
 *		Fields are not allowed to extend beyond the number of bits of
 *		precision, nor are they allowed to overlap with one another.
 *		
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Wednesday, January  7, 1998
 *
 * Modifications:
 *	Robb Matzke, 22 Dec 1998
 *	Also works for derived datatypes.
 *	
 *-------------------------------------------------------------------------
 */
herr_t
H5Tset_fields(hid_t type_id, size_t spos, size_t epos, size_t esize,
	      size_t mpos, size_t msize)
{
    H5T_t	*dt = NULL;
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_API(H5Tset_fields, FAIL)
    H5TRACE6("e","izzzzz",type_id,spos,epos,esize,mpos,msize);

    /* Check args */
    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a datatype")
    if (H5T_STATE_TRANSIENT!=dt->shared->state)
	HGOTO_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "datatype is read-only")
    while (dt->shared->parent)
        dt = dt->shared->parent; /*defer to parent*/
    if (H5T_FLOAT != dt->shared->type)
	HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "operation not defined for datatype class")
    if (epos + esize > dt->shared->u.atomic.prec)
	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "exponent bit field size/location is invalid")
    if (mpos + msize > dt->shared->u.atomic.prec)
	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "mantissa bit field size/location is invalid")
    if (spos >= dt->shared->u.atomic.prec)
	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "sign location is not valid")
    
    /* Check for overlap */
    if (spos >= epos && spos < epos + esize)
	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "sign bit appears within exponent field")
    if (spos >= mpos && spos < mpos + msize)
	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "sign bit appears within mantissa field")
    if ((mpos < epos && mpos + msize > epos) ||
            (epos < mpos && epos + esize > mpos))
	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "exponent and mantissa fields overlap")
    
    /* Commit */
    dt->shared->u.atomic.u.f.sign = spos;
    dt->shared->u.atomic.u.f.epos = epos;
    dt->shared->u.atomic.u.f.mpos = mpos;
    dt->shared->u.atomic.u.f.esize = esize;
    dt->shared->u.atomic.u.f.msize = msize;

done:
    FUNC_LEAVE_API(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5Tget_ebias
 *
 * Purpose:	Retrieves the exponent bias of a floating-point type.
 *
 * Return:	Success:	The bias
 *
 *		Failure:	0
 *
 * Programmer:	Robb Matzke
 *		Wednesday, January  7, 1998
 *
 * Modifications:
 *	Robb Matzke, 22 Dec 1998
 *	Also works with derived datatypes.
 *-------------------------------------------------------------------------
 */
size_t
H5Tget_ebias(hid_t type_id)
{
    H5T_t	*dt = NULL;
    size_t	ret_value;

    FUNC_ENTER_API(H5Tget_ebias, 0)
    H5TRACE1("z","i",type_id);

    /* Check args */
    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a datatype")
    while (dt->shared->parent)
        dt = dt->shared->parent; /*defer to parent*/
    if (H5T_FLOAT != dt->shared->type)
	HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, 0, "operation not defined for datatype class")
    
    /* bias */
    H5_ASSIGN_OVERFLOW(ret_value,dt->shared->u.atomic.u.f.ebias,uint64_t,size_t);

done:
    FUNC_LEAVE_API(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5Tset_ebias
 *
 * Purpose:	Sets the exponent bias of a floating-point type.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Wednesday, January  7, 1998
 *
 * Modifications:
 * 	Robb Matzke, 22 Dec 1998
 *	Also works with derived datatypes.
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Tset_ebias(hid_t type_id, size_t ebias)
{
    H5T_t	*dt = NULL;
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_API(H5Tset_ebias, FAIL)
    H5TRACE2("e","iz",type_id,ebias);

    /* Check args */
    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a datatype")
    if (H5T_STATE_TRANSIENT!=dt->shared->state)
	HGOTO_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "datatype is read-only")
    while (dt->shared->parent)
        dt = dt->shared->parent; /*defer to parent*/
    if (H5T_FLOAT != dt->shared->type)
	HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "operation not defined for datatype class")

    /* Commit */
    dt->shared->u.atomic.u.f.ebias = ebias;

done:
    FUNC_LEAVE_API(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5Tget_norm
 *
 * Purpose:	Returns the mantisssa normalization of a floating-point data
 *		type.
 *
 * Return:	Success:	Normalization ID
 *
 *		Failure:	H5T_NORM_ERROR (Negative)
 *
 * Programmer:	Robb Matzke
 *		Wednesday, January  7, 1998
 *
 * Modifications:
 * 	Robb Matzke, 22 Dec 1998
 *	Also works with derived datatypes.
 *
 *-------------------------------------------------------------------------
 */
H5T_norm_t
H5Tget_norm(hid_t type_id)
{
    H5T_t	*dt = NULL;
    H5T_norm_t	ret_value;

    FUNC_ENTER_API(H5Tget_norm, H5T_NORM_ERROR)
    H5TRACE1("Tn","i",type_id);

    /* Check args */
    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_NORM_ERROR, "not a datatype")
    while (dt->shared->parent)
        dt = dt->shared->parent; /*defer to parent*/
    if (H5T_FLOAT != dt->shared->type)
	HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, H5T_NORM_ERROR, "operation not defined for datatype class")
    
    /* norm */
    ret_value = dt->shared->u.atomic.u.f.norm;

done:
    FUNC_LEAVE_API(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5Tset_norm
 *
 * Purpose:	Sets the mantissa normalization method for a floating point
 *		datatype.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Wednesday, January  7, 1998
 *
 * Modifications:
 * 	Robb Matzke, 22 Dec 1998
 *	Also works for derived datatypes.
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Tset_norm(hid_t type_id, H5T_norm_t norm)
{
    H5T_t	*dt = NULL;
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_API(H5Tset_norm, FAIL)
    H5TRACE2("e","iTn",type_id,norm);

    /* Check args */
    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a datatype")
    if (H5T_STATE_TRANSIENT!=dt->shared->state)
	HGOTO_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "datatype is read-only")
    if (norm < H5T_NORM_IMPLIED || norm > H5T_NORM_NONE)
	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "illegal normalization")
    while (dt->shared->parent)
        dt = dt->shared->parent; /*defer to parent*/
    if (H5T_FLOAT != dt->shared->type)
	HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "operation not defined for datatype class")
    
    /* Commit */
    dt->shared->u.atomic.u.f.norm = norm;

done:
    FUNC_LEAVE_API(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5Tget_inpad
 *
 * Purpose:	If any internal bits of a floating point type are unused
 *		(that is, those significant bits which are not part of the
 *		sign, exponent, or mantissa) then they will be filled
 *		according to the value of this property.
 *
 * Return:	Success:	The internal padding type.
 *
 *		Failure:	H5T_PAD_ERROR (Negative)
 *
 * Programmer:	Robb Matzke
 *		Friday, January	 9, 1998
 *
 * Modifications:
 * 	Robb Matzke, 22 Dec 1998
 *	Also works for derived datatypes.
 *
 *-------------------------------------------------------------------------
 */
H5T_pad_t
H5Tget_inpad(hid_t type_id)
{
    H5T_t	*dt = NULL;
    H5T_pad_t	ret_value;

    FUNC_ENTER_API(H5Tget_inpad, H5T_PAD_ERROR)
    H5TRACE1("Tp","i",type_id);

    /* Check args */
    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_PAD_ERROR, "not a datatype")
    while (dt->shared->parent)
        dt = dt->shared->parent; /*defer to parent*/
    if (H5T_FLOAT != dt->shared->type)
	HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, H5T_PAD_ERROR, "operation not defined for datatype class")
    
    /* pad */
    ret_value = dt->shared->u.atomic.u.f.pad;

done:
    FUNC_LEAVE_API(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5Tset_inpad
 *
 * Purpose:	If any internal bits of a floating point type are unused
 *		(that is, those significant bits which are not part of the
 *		sign, exponent, or mantissa) then they will be filled
 *		according to the value of this property.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Friday, January	 9, 1998
 *
 * Modifications:
 * 	Robb Matzke, 22 Dec 1998
 *	Also works for derived datatypes.
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Tset_inpad(hid_t type_id, H5T_pad_t pad)
{
    H5T_t	*dt = NULL;
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_API(H5Tset_inpad, FAIL)
    H5TRACE2("e","iTp",type_id,pad);

    /* Check args */
    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a datatype")
    if (H5T_STATE_TRANSIENT!=dt->shared->state)
	HGOTO_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "datatype is read-only")
    if (pad < H5T_PAD_ZERO || pad >= H5T_NPAD)
	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "illegal internal pad type")
    while (dt->shared->parent)
        dt = dt->shared->parent; /*defer to parent*/
    if (H5T_FLOAT != dt->shared->type)
	HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "operation not defined for datatype class")
    
    /* Commit */
    dt->shared->u.atomic.u.f.pad = pad;

done:
    FUNC_LEAVE_API(ret_value)
}