xdr.h

VRTX 商用嵌入式实时操作系统

/***************************************************************************
*
*		Copyright (c) 1994 MICROTEC RESEARCH INCORPORATED.
*
*	All rights reserved. MICROTEC RESEARCH's source code is an unpublished
*	work and the use of a copyright notice does not imply otherwise.
*	This source code contains confidential, trade secret material of
*	MICROTEC RESEARCH. Any attempt or participation in deciphering,
*	decoding, reverse engineering or in any way altering the source code
*	is strictly prohibited, unless the prior written consent of
*	MICROTEC RESEARCH is obtained.
*
*
*	Module Name:		%M%
*
*	Identification:		%Z% %I% %M%
*
*	Date:			%G%  %U%
*
****************************************************************************
*/

/* @(#)xdr.h	2.2 88/07/29 4.0 RPCSRC */
/*
 * 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.h 1995 Microtec Research Inc.";*/

/*
 * xdr.h, External Data Representation Serialization Routines.
 *
 * Copyright (C) 1984, Sun Microsystems, Inc.
 */

#include <ansiprot.h>
#include <stdio.h>
#ifndef __XDR_HEADER__
#define __XDR_HEADER__

#ifdef __cplusplus
extern "C" {
#endif

/*
 * XDR provides a conventional way for converting between C data
 * types and an external bit-string representation.  Library supplied
 * routines provide for the conversion on built-in C data types.  These
 * routines and utility routines defined here are used to help implement
 * a type encode/decode routine for each user-defined type.
 *
 * Each data type provides a single procedure which takes two arguments:
 *
 *	bool_t
 *	xdrproc(xdrs, argresp)
 *		XDR *xdrs;
 *		<type> *argresp;
 *
 * xdrs is an instance of a XDR handle, to which or from which the data
 * type is to be converted.  argresp is a pointer to the structure to be
 * converted.  The XDR handle contains an operation field which indicates
 * which of the operations (ENCODE, DECODE * or FREE) is to be performed.
 *
 * XDR_DECODE may allocate space if the pointer argresp is null.  This
 * data can be freed with the XDR_FREE operation.
 *
 * We write only one procedure per data type to make it easy
 * to keep the encode and decode procedures for a data type consistent.
 * In many cases the same code performs all operations on a user defined type,
 * because all the hard work is done in the component type routines.
 * decode as a series of calls on the nested data types.
 */

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

/*
 * This is the number of bytes per unit of external data.
 */
#define BYTES_PER_XDR_UNIT	(4)
#define RNDUP(x)  ((((x) + BYTES_PER_XDR_UNIT - 1) / BYTES_PER_XDR_UNIT) \
		    * BYTES_PER_XDR_UNIT)

/*
 * The XDR handle.
 * Contains operation which is being applied to the stream,
 * an operations vector for the paticular implementation (e.g. see xdr_mem.c),
 * and two private fields for the use of the particular impelementation.
 */
typedef struct _xdr{
	enum xdr_op	x_op;		/* operation; fast additional param */
	struct xdr_ops {
	        /* get a long from underlying stream */
		bool_t	(*x_getlong) (ANSIPROT2(struct _xdr *, long *));
	        /* put a long to " */
		bool_t	(*x_putlong) (ANSIPROT2(struct _xdr *, long *));
	        /* get some bytes from " */
		bool_t	(*x_getbytes) (ANSIPROT3(struct _xdr *, caddr_t, u_int));
	        /* put some bytes to " */
		bool_t	(*x_putbytes) (ANSIPROT3(struct _xdr *, caddr_t, u_int));
	        /* returns bytes off from beginning */
		u_int	(*x_getpostn) (ANSIPROT1(struct _xdr *));
	        /* lets you reposition the stream */
		bool_t  (*x_setpostn) (ANSIPROT2(struct _xdr *, u_int));
	        /* buf quick ptr to buffered data */
		long *	(*x_inline) (ANSIPROT2(struct _xdr *, int));
	        /* free privates of this xdr_stream */
		void	(*x_destroy) (ANSIPROT1(struct _xdr *));	
	} *x_ops;
	caddr_t 	x_public;	/* users' data */
	caddr_t		x_private;	/* pointer to private data */
	caddr_t 	x_base;		/* private used for position info */
	int		x_handy;	/* extra private word */
} XDR;

/*
 * 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.
 * bool_t	(*xdrproc_t)(XDR *, caddr_t *);
 */
typedef	bool_t (*xdrproc_t) (ANSIPROT2(XDR *, caddr_t));

/*
 * Operations defined on a XDR handle
 *
 * XDR		*xdrs;
 * long		*longp;
 * caddr_t	 addr;
 * u_int	 len;
 * u_int	 pos;
 */
#define XDR_GETLONG(xdrs, longp)			\
	(*(xdrs)->x_ops->x_getlong)(xdrs, longp)
#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_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_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_putbytes(xdrs, addr, len)			\
	(*(xdrs)->x_ops->x_putbytes)(xdrs, addr, len)

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

#define XDR_SETPOS(xdrs, pos)				\
	(*(xdrs)->x_ops->x_setpostn)(xdrs, pos)
#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_inline(xdrs, len)				\
	(*(xdrs)->x_ops->x_inline)(xdrs, len)

#define	XDR_DESTROY(xdrs)				\
	if ((xdrs)->x_ops->x_destroy) 			\
		(*(xdrs)->x_ops->x_destroy)(xdrs)
#define	xdr_destroy(xdrs)				\
	if ((xdrs)->x_ops->x_destroy) 			\
		(*(xdrs)->x_ops->x_destroy)(xdrs)

/*
 * Support struct for discriminated unions.
 * You create an array of xdrdiscrim structures, terminated with
 * a entry with a null procedure pointer.  The xdr_union routine gets
 * the discriminant value and then searches the array of structures
 * for a matching value.  If a match is found the associated xdr routine
 * is called to handle that part of the union.  If there is
 * no match, then a default routine may be called.
 * If there is no match and no default routine it is an error.
 */
#define NULL_xdrproc_t ((xdrproc_t)0)
struct xdr_discrim {
	int	value;
	xdrproc_t proc;
};

/*
 * In-line routines for fast encode/decode of primitve data types.
 * Caveat emptor: these use single memory cycles to get the
 * data from the underlying buffer, and will fail to operate
 * properly if the data is not aligned.  The standard way to use these
 * is to say:
 *	if ((buf = XDR_INLINE(xdrs, count)) == NULL)
 *		return (FALSE);
 *	<<< macro calls >>>
 * where ``count'' is the number of bytes of data occupied
 * by the primitive data types.
 *
 * N.B. and frozen for all time: each data type here uses 4 bytes
 * of external representation.
 */
#define IXDR_GET_LONG(buf)			(long)ntohl((u_long)(*(buf))); buf++
#define IXDR_PUT_LONG(buf, v)		(*(buf)++ = (long)htonl((u_long)v))

#define IXDR_GET_BOOL(buf)			(bool_t)ntohl((u_long)(*(buf))); buf++
#define IXDR_GET_ENUM(buf, t)		(t)ntohl((u_long)(*(buf))); buf++
#define IXDR_GET_U_LONG(buf)		(u_long)ntohl((u_long)(*(buf))); buf++
#define IXDR_GET_SHORT(buf)			(short)ntohl((u_long)(*(buf))); buf++
#define IXDR_GET_U_SHORT(buf)		(u_short)ntohl((u_long)(*(buf))); buf++

#define IXDR_PUT_BOOL(buf, v)		IXDR_PUT_LONG((buf), ((long)(v)))
#define IXDR_PUT_ENUM(buf, v)		IXDR_PUT_LONG((buf), ((long)(v)))
#define IXDR_PUT_U_LONG(buf, v)		IXDR_PUT_LONG((buf), ((long)(v)))
#define IXDR_PUT_SHORT(buf, v)		IXDR_PUT_LONG((buf), ((long)(v)))
#define IXDR_PUT_U_SHORT(buf, v)	IXDR_PUT_LONG((buf), ((long)(v)))

#if 0
 Should not use buf++ inside XDR_GET macro since ntohl is a macro.
#define IXDR_GET_LONG(buf)		((long)ntohl((u_long)*(buf)++))

#define IXDR_GET_BOOL(buf)		((bool_t)IXDR_GET_LONG(buf))
#define IXDR_GET_ENUM(buf, t)		((t)IXDR_GET_LONG(buf))
#define IXDR_GET_U_LONG(buf)		((u_long)IXDR_GET_LONG(buf))
#define IXDR_GET_SHORT(buf)		((short)IXDR_GET_LONG(buf))
#define IXDR_GET_U_SHORT(buf)		((u_short)IXDR_GET_LONG(buf))
#endif

/*
 * These are the "generic" xdr routines.
 */
extern bool_t	xdr_void (ANSIPROT1(void));
extern bool_t	xdr_long_timeval (ANSIPROT1(void));
extern bool_t	xdr_int (ANSIPROT2(XDR *, caddr_t *));
extern bool_t	xdr_u_int (ANSIPROT2(XDR *, u_int *));
extern bool_t	xdr_long (ANSIPROT2(XDR *, long *));
extern bool_t	xdr_u_long (ANSIPROT2(XDR *, u_long *));
extern bool_t	xdr_short (ANSIPROT2(XDR *, short *));
extern bool_t	xdr_u_short (ANSIPROT2(XDR *, u_short *));
extern bool_t	xdr_bool (ANSIPROT2(XDR *, int *));
extern bool_t	xdr_enum (ANSIPROT2(XDR *, int *));
extern bool_t	xdr_array (ANSIPROT6(XDR *, caddr_t *, u_int *, u_int, u_int,
				   xdrproc_t));
extern bool_t	xdr_bytes (ANSIPROT4(XDR *, char **, u_int *, u_int));
extern bool_t	xdr_opaque (ANSIPROT3(XDR *, caddr_t, u_int));
extern bool_t	xdr_string (ANSIPROT3(XDR *, char **, u_int));
extern bool_t	xdr_union (ANSIPROT5(XDR *xdrs, int *dscmp, char *unp, struct
				   xdr_discrim *choices, xdrproc_t dfault)); 
extern bool_t	xdr_char (ANSIPROT2(XDR *, char *));
extern bool_t	xdr_u_char (ANSIPROT2(XDR *, char *));
extern bool_t	xdr_vector (ANSIPROT5(XDR *, char *basep, u_int nelem, u_int
				    elemsize, xdrproc_t xdr_elem));  
extern bool_t	xdr_float (ANSIPROT2(XDR *, float *));
extern bool_t	xdr_double (ANSIPROT2(XDR *, double *));
extern bool_t	xdr_reference (ANSIPROT4(XDR *, caddr_t *, u_int, xdrproc_t));
extern bool_t	xdr_pointer (ANSIPROT4(XDR *, char **, u_int, xdrproc_t));
extern bool_t	xdr_wrapstring (ANSIPROT2(XDR *, char **));

/*
 * Common opaque bytes objects used by many rpc protocols;
 * declared here due to commonality.
 */
#define MAX_NETOBJ_SZ 1024 
struct netobj {
	u_int	n_len;
	char	*n_bytes;
};
typedef struct netobj netobj;
extern bool_t   xdr_netobj (ANSIPROT2(XDR *, struct netobj *));

/*
 * These are the public routines for the various implementations of
 * xdr streams.
 */
/* XDR using memory buffers */
extern void   xdrmem_create (ANSIPROT4(XDR *xdrs, caddr_t addr, u_int size, enum
				     xdr_op op)); /* XDR using memory buffers */
/* XDR using stdio library */ 
extern void   xdrstdio_create (ANSIPROT3(XDR *xdrs, FILE *file, enum
				       xdr_op op)); 
/* XDR pseudo records for tcp */
struct ctdata;
extern void   xdrrec_create (ANSIPROT6(XDR *xdrs, register u_int sendsize,
				       register u_int recvsize, caddr_t
				       tcp_handle, int
				       (*readit)(struct ctdata *, caddr_t,
						 int),
				       int
				       (*writeit)(struct ctdata *, caddr_t,
						  int))); 
/* make end of xdr record */
extern bool_t xdrrec_endofrecord (ANSIPROT2(XDR *, int));
/* move to beginning of next record */
extern bool_t xdrrec_skiprecord (ANSIPROT1(XDR *));
/* true if no more input */
extern bool_t xdrrec_eof (ANSIPROT1(XDR *));		

#ifdef __cplusplus
}
#endif

#endif /* !__XDR_HEADER__ */