/*
 * 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
 */

#include <afsconfig.h>
#ifdef KERNEL
#include "afs/param.h"
#else
#include <afs/param.h>
#include <string.h>
#endif

RCSID
    ("$Header: /cvs/openafs/src/rx/xdr.c,v 1.9.2.3 2007/10/30 15:24:04 shadow Exp $");

/*
 * xdr.c, Generic XDR routines implementation.
 *
 * Copyright (C) 1984, Sun Microsystems, Inc.
 *
 * These are the "generic" xdr routines used to serialize and de-serialize
 * most common data items.  See xdr.h for more info on the interface to
 * xdr.
 */

#ifndef	NeXT

#ifdef	KERNEL
#include <sys/param.h>
#ifndef AFS_LINUX20_ENV
#include <sys/systm.h>
#endif
#else
#include <stdio.h>
#endif
#include "xdr.h"
#include "rx.h"

/*
 * constants specific to the xdr "protocol"
 */
#define XDR_FALSE	((afs_int32) 0)
#define XDR_TRUE	((afs_int32) 1)
#define LASTUNSIGNED	((u_int) 0-1)

/*
 * for unit alignment
 */


/*
 * XDR nothing
 */
bool_t
xdr_void(void)
{
    return (TRUE);
}

/*
 * XDR integers
 */
bool_t
xdr_int(register XDR * xdrs, int *ip)
{
    afs_int32 l;

    switch (xdrs->x_op) {

    case XDR_ENCODE:
	l = (afs_int32) * ip;
	return (XDR_PUTINT32(xdrs, &l));

    case XDR_DECODE:
	if (!XDR_GETINT32(xdrs, &l)) {
	    return (FALSE);
	}
	*ip = (int)l;
	return (TRUE);

    case XDR_FREE:
	return (TRUE);
    }
    return (FALSE);
}

/*
 * XDR unsigned integers
 */
bool_t
xdr_u_int(register XDR * xdrs, u_int * uip)
{
    afs_uint32 l;

    switch (xdrs->x_op) {

    case XDR_ENCODE:
	l = (afs_uint32) * uip;
	return (XDR_PUTINT32(xdrs, &l));

    case XDR_DECODE:
	if (!XDR_GETINT32(xdrs, &l)) {
	    return (FALSE);
	}
	*uip = (u_int) l;
	return (TRUE);

    case XDR_FREE:
	return (TRUE);
    }
    return (FALSE);
}


/*
 * XDR long integers
 */
bool_t
xdr_long(register XDR * xdrs, long *lp)
{
    afs_int32 l;

    switch (xdrs->x_op) {

    case XDR_ENCODE:
	l = (afs_int32) * lp;
	return (XDR_PUTINT32(xdrs, &l));

    case XDR_DECODE:
	if (!XDR_GETINT32(xdrs, &l)) {
	    return (FALSE);
	}
	*lp = (long)l;
	return (TRUE);

    case XDR_FREE:
	return (TRUE);
    }
    return (FALSE);
}

/*
 * XDR unsigned long integers
 */
bool_t
xdr_u_long(register XDR * xdrs, u_long * ulp)
{
    afs_uint32 l;

    switch (xdrs->x_op) {

    case XDR_ENCODE:
	l = (afs_uint32) * ulp;
	return (XDR_PUTINT32(xdrs, &l));

    case XDR_DECODE:
	if (!XDR_GETINT32(xdrs, &l)) {
	    return (FALSE);
	}
	*ulp = (u_long) l;
	return (TRUE);

    case XDR_FREE:
	return (TRUE);
    }
    return (FALSE);
}


/*
 * XDR chars
 */
bool_t
xdr_char(register XDR * xdrs, char *sp)
{
    afs_int32 l;

    switch (xdrs->x_op) {

    case XDR_ENCODE:
	l = (afs_int32) * sp;
	return (XDR_PUTINT32(xdrs, &l));

    case XDR_DECODE:
	if (!XDR_GETINT32(xdrs, &l)) {
	    return (FALSE);
	}
	*sp = (char)l;
	return (TRUE);

    case XDR_FREE:
	return (TRUE);
    }
    return (FALSE);
}

/*
 * XDR unsigned chars
 */
bool_t
xdr_u_char(register XDR * xdrs, u_char * usp)
{
    afs_uint32 l;

    switch (xdrs->x_op) {

    case XDR_ENCODE:
	l = (afs_uint32) * usp;
	return (XDR_PUTINT32(xdrs, &l));

    case XDR_DECODE:
	if (!XDR_GETINT32(xdrs, &l)) {
	    return (FALSE);
	}
	*usp = (u_char) l;
	return (TRUE);

    case XDR_FREE:
	return (TRUE);
    }
    return (FALSE);
}


/*
 * XDR short integers
 */
bool_t
xdr_short(register XDR * xdrs, short *sp)
{
    afs_int32 l;

    switch (xdrs->x_op) {

    case XDR_ENCODE:
	l = (afs_int32) * sp;
	return (XDR_PUTINT32(xdrs, &l));

    case XDR_DECODE:
	if (!XDR_GETINT32(xdrs, &l)) {
	    return (FALSE);
	}
	*sp = (short)l;
	return (TRUE);

    case XDR_FREE:
	return (TRUE);
    }
    return (FALSE);
}

/*
 * XDR unsigned short integers
 */
bool_t
xdr_u_short(register XDR * xdrs, u_short * usp)
{
    afs_uint32 l;

    switch (xdrs->x_op) {

    case XDR_ENCODE:
	l = (afs_uint32) * usp;
	return (XDR_PUTINT32(xdrs, &l));

    case XDR_DECODE:
	if (!XDR_GETINT32(xdrs, &l)) {
	    return (FALSE);
	}
	*usp = (u_short) l;
	return (TRUE);

    case XDR_FREE:
	return (TRUE);
    }
    return (FALSE);
}


/*
 * XDR booleans
 */
bool_t
xdr_bool(register XDR * xdrs, bool_t * bp)
{
    afs_int32 lb;

    switch (xdrs->x_op) {

    case XDR_ENCODE:
	lb = *bp ? XDR_TRUE : XDR_FALSE;
	return (XDR_PUTINT32(xdrs, &lb));

    case XDR_DECODE:
	if (!XDR_GETINT32(xdrs, &lb)) {
	    return (FALSE);
	}
	*bp = (lb == XDR_FALSE) ? FALSE : TRUE;
	return (TRUE);

    case XDR_FREE:
	return (TRUE);
    }
    return (FALSE);
}

/*
 * XDR enumerations
 */
bool_t
xdr_enum(register XDR * xdrs, enum_t * ep)
{
    enum sizecheck { SIZEVAL };	/* used to find the size of an enum */

    /*
     * enums are treated as ints
     */

    return (xdr_long(xdrs, (long *)ep));

}

/*
 * XDR opaque data
 * Allows the specification of a fixed size sequence of opaque bytes.
 * cp points to the opaque object and cnt gives the byte length.
 */
bool_t
xdr_opaque(register XDR * xdrs, caddr_t cp, register u_int cnt)
{
    register u_int rndup;
    int crud[BYTES_PER_XDR_UNIT];
    char xdr_zero[BYTES_PER_XDR_UNIT] = { 0, 0, 0, 0 };

    /*
     * if no data we are done
     */
    if (cnt == 0)
	return (TRUE);

    /*
     * round byte count to full xdr units
     */
    rndup = cnt % BYTES_PER_XDR_UNIT;
    if (rndup > 0)
	rndup = BYTES_PER_XDR_UNIT - rndup;

    if (xdrs->x_op == XDR_DECODE) {
	if (!XDR_GETBYTES(xdrs, cp, cnt)) {
	    return (FALSE);
	}
	if (rndup == 0)
	    return (TRUE);
	return (XDR_GETBYTES(xdrs, (caddr_t)crud, rndup));
    }

    if (xdrs->x_op == XDR_ENCODE) {
	if (!XDR_PUTBYTES(xdrs, cp, cnt)) {
	    return (FALSE);
	}
	if (rndup == 0)
	    return (TRUE);
	return (XDR_PUTBYTES(xdrs, xdr_zero, rndup));
    }

    if (xdrs->x_op == XDR_FREE) {
	return (TRUE);
    }

    return (FALSE);
}

/*
 * XDR counted bytes
 * *cpp is a pointer to the bytes, *sizep is the count.
 * If *cpp is NULL maxsize bytes are allocated
 */
bool_t
xdr_bytes(register XDR * xdrs, char **cpp, register u_int * sizep,
	  u_int maxsize)
{
    register char *sp = *cpp;	/* sp is the actual string pointer */
    register u_int nodesize;

    /*
     * first deal with the length since xdr bytes are counted
     */
    if (!xdr_u_int(xdrs, sizep)) {
	return (FALSE);
    }
    nodesize = *sizep;
    if ((nodesize > maxsize) && (xdrs->x_op != XDR_FREE)) {
	return (FALSE);
    }

    /*
     * now deal with the actual bytes
     */
    switch (xdrs->x_op) {

    case XDR_DECODE:
	if (sp == NULL) {
	    *cpp = sp = (char *)osi_alloc(nodesize);
	}
	if (sp == NULL) {
	    return (FALSE);
	}
	/* fall into ... */

    case XDR_ENCODE:
	return (xdr_opaque(xdrs, sp, nodesize));

    case XDR_FREE:
	if (sp != NULL) {
	    osi_free(sp, nodesize);
	    *cpp = NULL;
	}
	return (TRUE);
    }
    return (FALSE);
}

/*
 * XDR a descriminated union
 * Support routine for discriminated unions.
 * You create an array of xdrdiscrim structures, terminated with
 * an entry with a null procedure pointer.  The routine gets
 * the discriminant value and then searches the array of xdrdiscrims
 * looking for that value.  It calls the procedure given in the xdrdiscrim
 * to handle the discriminant.  If there is no specific routine a default
 * routine may be called.
 * If there is no specific or default routine an error is returned.
 */
/*
	enum_t *dscmp;		* enum to decide which arm to work on *
	caddr_t unp;		* the union itself *
	struct xdr_discrim *choices;	* [value, xdr proc] for each arm *
	xdrproc_t dfault;	* default xdr routine *
*/
bool_t
xdr_union(register XDR * xdrs, enum_t * dscmp, caddr_t unp,
	  struct xdr_discrim * choices, xdrproc_t dfault)
{
    register enum_t dscm;

    /*
     * we deal with the discriminator;  it's an enum
     */
    if (!xdr_enum(xdrs, dscmp)) {
	return (FALSE);
    }
    dscm = *dscmp;

    /*
     * search choices for a value that matches the discriminator.
     * if we find one, execute the xdr routine for that value.
     */
    for (; choices->proc != NULL_xdrproc_t; choices++) {
	if (choices->value == dscm)
	    return ((*(choices->proc)) (xdrs, unp, LASTUNSIGNED));
    }

    /*
     * no match - execute the default xdr routine if there is one
     */
    return ((dfault == NULL_xdrproc_t) ? FALSE : (*dfault) (xdrs, unp,
							    LASTUNSIGNED));
}


/*
 * Non-portable xdr primitives.
 * Care should be taken when moving these routines to new architectures.
 */


/*
 * XDR null terminated ASCII strings
 * xdr_string deals with "C strings" - arrays of bytes that are
 * terminated by a NULL character.  The parameter cpp references a
 * pointer to storage; If the pointer is null, then the necessary
 * storage is allocated.  The last parameter is the max allowed length
 * of the string as specified by a protocol.
 */
bool_t
xdr_string(register XDR * xdrs, char **cpp, u_int maxsize)
{
    register char *sp = *cpp;	/* sp is the actual string pointer */
    u_int size;
    u_int nodesize;

    /* FIXME: this does not look correct: MSVC 6 computes -2 here */
    if (maxsize > ((~0) >> 1) - 1)
	maxsize = ((~0) >> 1) - 1;

    /*
     * first deal with the length since xdr strings are counted-strings
     */
    switch (xdrs->x_op) {
    case XDR_FREE:
	if (sp == NULL) {
	    return (TRUE);	/* already free */
	}
	/* Fall through */
    case XDR_ENCODE:
	size = strlen(sp);
	break;
    case XDR_DECODE:
	break;
    }

    if (!xdr_u_int(xdrs, &size)) {
	return (FALSE);
    }
    if (size > maxsize) {
	return (FALSE);
    }
    nodesize = size + 1;

    /*
     * now deal with the actual bytes
     */
    switch (xdrs->x_op) {

    case XDR_DECODE:
	if (sp == NULL)
	    *cpp = sp = (char *)osi_alloc(nodesize);
	if (sp == NULL) {
	    return (FALSE);
	}
	sp[size] = 0;
	/* fall into ... */

    case XDR_ENCODE:
	return (xdr_opaque(xdrs, sp, size));

    case XDR_FREE:
	if (sp != NULL) {
	    osi_free(sp, nodesize);
	    *cpp = NULL;
	}
	return (TRUE);
    }
    return (FALSE);
}

/* 
 * Wrapper for xdr_string that can be called directly from 
 * routines like clnt_call
 */
#ifndef	KERNEL
bool_t
xdr_wrapstring(register XDR * xdrs, char **cpp)
{
    if (xdr_string(xdrs, cpp, BUFSIZ)) {
	return (TRUE);
    }
    return (FALSE);
}
#endif
#endif /* NeXT */