/*
 * Copyright (C) 1998 Spizella Software
 *                    All rights reserved.
 *
 * Programmer:  Robb Matzke <robb@arborea.spizella.com>
 *              Tuesday, January 13, 1998
 *
 * Purpose:	Data type conversions.
 */
#define H5T_PACKAGE		/*suppress error about including H5Tpkg	*/

#include <H5Eprivate.h>
#include <H5Tpkg.h>

/* Interface initialization */
static intn interface_initialize_g = FALSE;
#define INTERFACE_INIT NULL


/*-------------------------------------------------------------------------
 * Function:	H5T_conv_noop
 *
 * Purpose:	The no-op conversion.  The library knows about this
 *		conversion without it being registered.
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	never fails
 *
 * Programmer:	Robb Matzke
 *              Wednesday, January 14, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5T_conv_noop (hid_t src_id, hid_t dst_id, size_t nelmts,
	       void *buf, const void *background)
{
   FUNC_ENTER (H5T_conv_noop, FAIL);
   FUNC_LEAVE (SUCCEED);
}
   

/*-------------------------------------------------------------------------
 * Function:	H5T_conv_order
 *
 * Purpose:	Convert one type to another when byte order is the only
 *		difference.
 *
 * Note:	This is a soft conversion function.
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Tuesday, January 13, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5T_conv_order (hid_t src_id, hid_t dst_id, size_t nelmts,
		void *_buf, const void *background)
{
   uint8	*buf = (uint8*)_buf;
   uint8	tmp;
   H5T_t	*src = NULL;
   H5T_t	*dst = NULL;
   intn		i, j, md;
   
   FUNC_ENTER (H5T_conv_order, FAIL);

   /* Check args */
   if (H5_DATATYPE!=H5Aatom_group (src_id) ||
       NULL==(src=H5Aatom_object (src_id)) ||
       H5_DATATYPE!=H5Aatom_group (dst_id) ||
       NULL==(dst=H5Aatom_object (dst_id))) {
      HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
   }
   if (background) {
      HRETURN_ERROR (H5E_ARGS, H5E_UNSUPPORTED, FAIL,
		     "background values not supported in this conv path");
   }
   
   if (!buf) {
      /* Capability query */
      if (src->size!=dst->size ||
	  0!=src->u.atomic.offset ||
	  0!=dst->u.atomic.offset ||
	  !((H5T_ORDER_BE==src->u.atomic.order &&
	     H5T_ORDER_LE==dst->u.atomic.order) ||
	    (H5T_ORDER_LE==src->u.atomic.order &&
	     H5T_ORDER_BE==dst->u.atomic.order))) {
	 HRETURN_ERROR (H5E_DATATYPE, H5E_UNSUPPORTED, FAIL,
			"conversion not supported");
      }
      
      switch (src->type) {
      case H5T_INTEGER:
	 /* nothing to check */
	 break;

      case H5T_FLOAT:
	 if (src->u.atomic.u.f.sign!=dst->u.atomic.u.f.sign ||
	     src->u.atomic.u.f.epos!=dst->u.atomic.u.f.epos ||
	     src->u.atomic.u.f.esize!=dst->u.atomic.u.f.esize ||
	     src->u.atomic.u.f.ebias!=dst->u.atomic.u.f.ebias ||
	     src->u.atomic.u.f.mpos!=dst->u.atomic.u.f.mpos ||
	     src->u.atomic.u.f.msize!=dst->u.atomic.u.f.msize ||
	     src->u.atomic.u.f.norm!=dst->u.atomic.u.f.norm ||
	     src->u.atomic.u.f.pad!=dst->u.atomic.u.f.pad) {
	    HRETURN_ERROR (H5E_DATATYPE, H5E_UNSUPPORTED, FAIL,
			   "conversion not supported");
	 }
	 break;

      default:
	 HRETURN_ERROR (H5E_DATATYPE, H5E_UNSUPPORTED, FAIL,
			"conversion not supported");
      }
      HRETURN (SUCCEED);
   }
   

   /* The conversion */
   md = src->size / 2;
   for (i=0; i<nelmts; i++, buf+=src->size) {
      for (j=0; j<md; j++) {
	 tmp = buf[j];
	 buf[j] = buf[src->size-(j+1)];
	 buf[src->size-(j+1)] = tmp;
      }
   }

   FUNC_LEAVE (SUCCEED);
}