/*
 * $Id: gmx_system_xdr.h,v 1.3 2003/11/17 21:50:40 spoel Exp $
 * 
 *                This source code is part of
 * 
 *                 G   R   O   M   A   C   S
 * 
 *          GROningen MAchine for Chemical Simulations
 * 
 *                        VERSION 3.2.0
 * Written by David van der Spoel, Erik Lindahl, Berk Hess, and others.
 * Copyright (c) 1991-2000, University of Groningen, The Netherlands.
 * Copyright (c) 2001-2004, The GROMACS development team,
 * check out http://www.gromacs.org for more information.

 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * If you want to redistribute modifications, please consider that
 * scientific software is very special. Version control is crucial -
 * bugs must be traceable. We will be happy to consider code for
 * inclusion in the official distribution, but derived work must not
 * be called official GROMACS. Details are found in the README & COPYING
 * files - if they are missing, get the official version at www.gromacs.org.
 * 
 * To help us fund GROMACS development, we humbly ask that you cite
 * the papers on the package - you can find them in the top README file.
 * 
 * For more info, check our website at http://www.gromacs.org
 * 
 * And Hey:
 * Gromacs Runs On Most of All Computer Systems
 */

#ifndef _gmx_system_xdr_h
#define _gmx_system_xdr_h

#include <limits.h>
#include <stdio.h>
#include <stdlib.h>


/*
 * This header file is ONLY used on windows systems, since these do
 * not include the XDR routines present on a unix machine. It will
 * most probably work on other platforms too, but make sure you
 * test that the xtc files produced are ok before using it. 
 *
 * This header file contains Gromacs versions of the definitions for 
 * Sun External Data Representation (XDR) headers and routines.
 *
 * On most UNIX systems this is already present as part of your 
 * system libraries, but since we want to make Gromacs portable to
 * platforms like Microsoft Windows we have created a private version
 * of the necessary routines and distribute them with the Gromacs source.
 * 
 * Although the rest of Gromacs is GPL, you can copy and use the XDR 
 * routines in any way you want as long as you obey Sun's license:
 *
 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
 * unrestricted use provided that this legend is included on all tape
 * media and as a part of the software program in whole or part.  Users
 * may copy or modify Sun RPC without charge, but are not authorized
 * to license or distribute it to anyone else except as part of a product or
 * program developed by the user.
 *
 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
 *
 * Sun RPC is provided with no support and without any obligation on the
 * part of Sun Microsystems, Inc. to assist in its use, correction,
 * modification or enhancement.
 *
 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
 * OR ANY PART THEREOF.
 *
 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
 * or profits or other special, indirect and consequential damages, even if
 * Sun has been advised of the possibility of such damages.
 *
 * Sun Microsystems, Inc.
 * 2550 Garcia Avenue
 * Mountain View, California  94043
 */ 

/*
 * Xdr operations.  XDR_ENCODE causes the type to be encoded into the
 * stream.  XDR_DECODE causes the type to be extracted from the stream.
 * XDR_FREE can be used to release the space allocated by an 
 * XDR_DECODE request.
 */

/* We already have a boolean type in Gromacs, but the XDR library
 * one has a slightly different name (the calls should be identical).
 */
typedef int bool_t;

/* 
 * Aninteger type that is 32 bits wide. Check if int,
 * long or short is 32 bits and die if none of them is :-)
 */
#if (INT_MAX == 2147483647)
   typedef int xdr_int32_t;
   typedef unsigned int xdr_uint32_t;
#elif (LONG_MAX == 2147483647L)
   typedef long xdr_int32_t;
   typedef unsigned long xdr_uint32_t;
#elif (SHRT_MAX == 2147483647)
   typedef short xdr_int32_t;
   typedef unsigned short xdr_uint32_t;
#else
#  error ERROR: No 32 bit wide integer type found!
#endif


enum xdr_op {
  XDR_ENCODE = 0,
  XDR_DECODE = 1,
  XDR_FREE = 2
};

#ifndef FALSE
#      define  FALSE   (0)
#endif
#ifndef TRUE
#      define  TRUE    (1)
#endif


#define BYTES_PER_XDR_UNIT	(4)
/* Macro to round up to units of 4. */
#define XDR_RNDUP(x)  (((x) + BYTES_PER_XDR_UNIT - 1) & ~(BYTES_PER_XDR_UNIT - 1))


/*
 * The XDR handle.
 * Contains operation which is being applied to the stream,
 * an operations vector for the particular implementation (e.g. see xdr_mem.c),
 * and two private fields for the use of the particular implementation.
 */
typedef struct XDR XDR;
struct XDR
  {
    enum xdr_op x_op;		/* operation; fast additional param */
    struct xdr_ops
      {
	bool_t (*x_getlong) (XDR *__xdrs, long *__lp);
	/* get a long from underlying stream */
	bool_t (*x_putlong) (XDR *__xdrs, long *__lp);
	/* put a long to " */
	bool_t (*x_getbytes) (XDR *__xdrs, char *__addr, unsigned int __len);
	/* get some bytes from " */
	bool_t (*x_putbytes) (XDR *__xdrs, char *__addr, unsigned int __len);
	/* put some bytes to " */
	unsigned int (*x_getpostn) (XDR *__xdrs);
	/* returns bytes off from beginning */
	bool_t (*x_setpostn) (XDR *__xdrs, unsigned int __pos);
	/* lets you reposition the stream */
	xdr_int32_t *(*x_inline) (XDR *__xdrs, int __len);
	/* buf quick ptr to buffered data */
	void (*x_destroy) (XDR *__xdrs);
	/* free privates of this xdr_stream */
	bool_t (*x_getint32) (XDR *__xdrs, xdr_int32_t *__ip);
	/* get a int from underlying stream */
	bool_t (*x_putint32) (XDR *__xdrs, xdr_int32_t *__ip);
	/* put a int to " */
      }
     *x_ops;
    char *x_public;		/* users' data */
    char *x_private;		/* pointer to private data */
    char *x_base;		/* private used for position info */
    int x_handy;		/* extra private word */
  };

/*
 * A xdrproc_t exists for each data type which is to be encoded or decoded.
 *
 * The second argument to the xdrproc_t is a pointer to an opaque pointer.
 * The opaque pointer generally points to a structure of the data type
 * to be decoded.  If this pointer is 0, then the type routines should
 * allocate dynamic storage of the appropriate size and return it.
 */

typedef bool_t (*xdrproc_t) (XDR *, void *,...);

/*
 * Operations defined on a XDR handle
 *
 * XDR          *xdrs;
 * xdr_int32_t  *int32p;
 * long         *longp;
 * char         *addr;
 * unsigned int  len;
 * unsigned int  pos;
 */


#define xdr_getint32(xdrs, int32p)                      \
        (*(xdrs)->x_ops->x_getint32)(xdrs, int32p)

#define xdr_putint32(xdrs, int32p)                      \
        (*(xdrs)->x_ops->x_putint32)(xdrs, int32p)

#define xdr_getlong(xdrs, longp)			\
	(*(xdrs)->x_ops->x_getlong)(xdrs, longp)

#define xdr_putlong(xdrs, longp)			\
	(*(xdrs)->x_ops->x_putlong)(xdrs, longp)

#define xdr_getbytes(xdrs, addr, len)			\
	(*(xdrs)->x_ops->x_getbytes)(xdrs, addr, len)

#define xdr_putbytes(xdrs, addr, len)			\
	(*(xdrs)->x_ops->x_putbytes)(xdrs, addr, len)

#define xdr_getpos(xdrs)				\
	(*(xdrs)->x_ops->x_getpostn)(xdrs)

#define xdr_setpos(xdrs, pos)				\
	(*(xdrs)->x_ops->x_setpostn)(xdrs, pos)

#define	xdr_inline(xdrs, len)				\
	(*(xdrs)->x_ops->x_inline)(xdrs, len)

#define	xdr_destroy(xdrs)					\
	do {							\
		if ((xdrs)->x_ops->x_destroy)			\
			(*(xdrs)->x_ops->x_destroy)(xdrs);	\
	} while (0)


extern bool_t xdr_u_short (XDR *__xdrs, unsigned short *__usp);
extern bool_t xdr_int (XDR *__xdrs, int *__ip);
extern bool_t xdr_long (XDR *__xdrs, long *__lp); 
extern bool_t xdr_u_long (XDR *__xdrs, unsigned long *__ulp); 
extern bool_t xdr_bool (XDR *__xdrs, int *__bp);
extern bool_t xdr_opaque (XDR *__xdrs, char *__cp, unsigned int __cnt);
extern bool_t xdr_string (XDR *__xdrs, char **__cpp, unsigned int __maxsize);
extern bool_t xdr_char (XDR *__xdrs, char *__cp);
extern bool_t xdr_u_char (XDR *__xdrs, unsigned char *__cp);
extern bool_t xdr_vector (XDR *__xdrs, char *__basep, unsigned int __nelem,
			  unsigned int __elemsize, xdrproc_t __xdr_elem);
extern bool_t xdr_float (XDR *__xdrs, float *__fp);
extern bool_t xdr_double (XDR *__xdrs, double *__dp);
extern void xdrstdio_create (XDR *__xdrs, FILE *__file, enum xdr_op __xop);

/* free memory buffers for xdr */
extern void xdr_free (xdrproc_t __proc, char *__objp);


#endif /* _gmx_system_xdr_h */

