/* $Id: xdr.c,v 1.2 1999/01/19 02:36:43 kaminsky Exp $ */

/*
 * 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.c, Generic XDR routines implementation.
 *
 * Copyright (C) 1986, 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.
 */

#include "arpc.h"

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

/*
 * for unit alignment
 */
static char xdr_zero[BYTES_PER_XDR_UNIT] = {0, 0, 0, 0};

/*
 * Free a data structure using XDR
 * Not a filter, but a convenient utility nonetheless
 */
void
(xdr_free) (xdrproc_t proc, char *objp)
{
  XDR x;

  x.x_op = XDR_FREE;
  (*proc) (&x, objp);
}

/*
 * XDR nothing
 */
bool_t
xdr_void (void)
	/* XDR *xdrs; */
	/* caddr_t addr; */
{

  return (TRUE);
}


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

  switch (xdrs->x_op) {

  case XDR_ENCODE:
    l = (long) *ip;
    return (XDR_PUTLONG (xdrs, &l));

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

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

/*
 * XDR unsigned integers
 */
bool_t
xdr_u_int (XDR *xdrs, u_int * up)
{
  u_long l;

  switch (xdrs->x_op) {

  case XDR_ENCODE:
    l = (u_long) * up;
    return (XDR_PUTLONG (xdrs, (long *) &l));

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

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


/*
 * XDR long integers
 * same as xdr_u_long - open coded to save a proc call!
 */
bool_t
xdr_long (register XDR *xdrs, long int *lp)
{
  switch (xdrs->x_op) {
  case XDR_ENCODE:
    return (XDR_PUTLONG (xdrs, lp));
  case XDR_DECODE:
    return (XDR_GETLONG (xdrs, lp));
  case XDR_FREE:
    return (TRUE);
  }

  return (FALSE);
}

/*
 * XDR unsigned long integers
 * same as xdr_long - open coded to save a proc call!
 */
bool_t
xdr_u_long (register XDR *xdrs, u_long * ulp)
{
  switch (xdrs->x_op) {
  case XDR_ENCODE:
    return (XDR_PUTLONG (xdrs, (long *) ulp));
  case XDR_DECODE:
    return (XDR_GETLONG (xdrs, (long *) ulp));
  case XDR_FREE:
    return (TRUE);
  }
  return (FALSE);
}


/*
 * XDR 32-bit integers
 * same as xdr_u_int32_t - open coded to save a proc call!
 */
bool_t
xdr_int32_t (register XDR *xdrs, int32_t * int32_p)
{
  long l;

  switch (xdrs->x_op) {

  case XDR_ENCODE:
    l = (long) *int32_p;
    return (XDR_PUTLONG (xdrs, &l));

  case XDR_DECODE:
    if (!XDR_GETLONG (xdrs, &l)) {
      return (FALSE);
    }
    *int32_p = (int32_t) l;
    return (TRUE);

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

/*
 * XDR unsigned 32-bit integers
 * same as xdr_int32_t - open coded to save a proc call!
 */
bool_t
xdr_u_int32_t (register XDR *xdrs, u_int32_t * u_int32_p)
{
  u_long l;

  switch (xdrs->x_op) {

  case XDR_ENCODE:
    l = (u_long) * u_int32_p;
    return (XDR_PUTLONG (xdrs, (long *) &l));

  case XDR_DECODE:
    if (!XDR_GETLONG (xdrs, (long *) &l)) {
      return (FALSE);
    }
    *u_int32_p = (u_int32_t) l;
    return (TRUE);

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


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

  switch (xdrs->x_op) {

  case XDR_ENCODE:
    l = (long) *sp;
    return (XDR_PUTLONG (xdrs, &l));

  case XDR_DECODE:
    if (!XDR_GETLONG (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)
{
  u_long l;

  switch (xdrs->x_op) {

  case XDR_ENCODE:
    l = (u_long) * usp;
    return (XDR_PUTLONG (xdrs, (long *) &l));

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

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


/*
 * XDR 16-bit integers
 */
bool_t
xdr_int16_t (register XDR *xdrs, int16_t * int16_p)
{
  long l;

  switch (xdrs->x_op) {

  case XDR_ENCODE:
    l = (long) *int16_p;
    return (XDR_PUTLONG (xdrs, &l));

  case XDR_DECODE:
    if (!XDR_GETLONG (xdrs, &l)) {
      return (FALSE);
    }
    *int16_p = (int16_t) l;
    return (TRUE);

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

/*
 * XDR unsigned 16-bit integers
 */
bool_t
xdr_u_int16_t (register XDR *xdrs, u_int16_t * u_int16_p)
{
  u_long l;

  switch (xdrs->x_op) {

  case XDR_ENCODE:
    l = (u_long) * u_int16_p;
    return (XDR_PUTLONG (xdrs, (long *) &l));

  case XDR_DECODE:
    if (!XDR_GETLONG (xdrs, (long *) &l)) {
      return (FALSE);
    }
    *u_int16_p = (u_int16_t) l;
    return (TRUE);

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


/*
 * XDR a char
 */
bool_t
xdr_char (XDR *xdrs, char *cp)
{
  int i;

  i = (*cp);
  if (!xdr_int (xdrs, &i)) {
    return (FALSE);
  }
  *cp = i;
  return (TRUE);
}

/*
 * XDR an unsigned char
 */
bool_t
xdr_u_char (XDR *xdrs, u_char * cp)
{
  u_int u;

  u = (*cp);
  if (!xdr_u_int (xdrs, &u)) {
    return (FALSE);
  }
  *cp = u;
  return (TRUE);
}

/*
 * XDR booleans
 */
bool_t
xdr_bool (register XDR *xdrs, int32_t * bp)
{
  long lb;

  switch (xdrs->x_op) {

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

  case XDR_DECODE:
    if (!XDR_GETLONG (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 (XDR *xdrs, int32_t * ep)
{
#ifndef lint
  enum sizecheck {
    SIZEVAL
  };				/* used to find the size of an enum */

  /*
   * enums are treated as ints
   */
  if (sizeof (enum sizecheck) == sizeof (long)) {
    return (xdr_long (xdrs, (long *) ep));
  }
  else if (sizeof (enum sizecheck) == sizeof (int)) {
    return (xdr_int (xdrs, (int *) ep));
  }
  else if (sizeof (enum sizecheck) == sizeof (short)) {
    return (xdr_short (xdrs, (short *) ep));
  }
  else {
    return (FALSE);
  }
#else
  (void) (xdr_short (xdrs, (short *) ep));
  (void) (xdr_int (xdrs, (int *) ep));
  return (xdr_long (xdrs, (long *) ep));
#endif
}

/*
 * 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;
  static int crud[BYTES_PER_XDR_UNIT];

  /*
   * 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 (nodesize == 0) {
      return (TRUE);
    }
    if (sp == NULL) {
      *cpp = sp = (char *) mem_alloc (nodesize);
    }
    if (sp == NULL) {
      warn ("xdr_bytes: out of memory\n");
      return (FALSE);
    }
    /* fall into ... */

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

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

/*
 * Implemented here due to commonality of the object.
 */
bool_t
xdr_netobj (XDR *xdrs, struct netobj * np)
{

  return (xdr_bytes (xdrs, &np->n_bytes, &np->n_len, MAX_NETOBJ_SZ));
}

/*
 * 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.
 */
bool_t
xdr_union (register XDR *xdrs, int32_t * dscmp, char *unp, struct xdr_discrim * choices, xdrproc_t dfault)
				/* enum to decide which arm to work on */
				/* the union itself */
					/* [value, xdr proc] for each arm */
				/* default xdr routine */
{
  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));
  }

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


/*
 * 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;

  /*
   * 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 (nodesize == 0) {
      return (TRUE);
    }
    if (sp == NULL)
      *cpp = sp = (char *) mem_alloc (nodesize);
    if (sp == NULL) {
      warn ("xdr_string: out of memory\n");
      return (FALSE);
    }
    sp[size] = 0;
    /* fall into ... */

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

  case XDR_FREE:
    mem_free (sp, nodesize);
    *cpp = NULL;
    return (TRUE);
  }
  return (FALSE);
}

/* 
 * Wrapper for xdr_string that can be called directly from 
 * routines like clnt_call
 */
bool_t
xdr_wrapstring (XDR *xdrs, char **cpp)
{
  return xdr_string (xdrs, cpp, LASTUNSIGNED);
}

bool_t
xdr_u_int64_t (XDR *xdrs, u_int64_t *qp)
{
  long l, h;

  switch (xdrs->x_op) {
  case XDR_ENCODE:
    l = (long) (*qp & 0xffffffff);
    h = (long) ((*qp>>32) & 0xffffffff);
    return XDR_PUTLONG (xdrs, &h) && XDR_PUTLONG (xdrs, &l);
  case XDR_DECODE:
    if (!XDR_GETLONG (xdrs, &h) || !XDR_GETLONG (xdrs, &l))
      return FALSE;
    *qp = (u_int32_t) l | ((u_int64_t) h << 32);
    return TRUE;
  case XDR_FREE:
    return TRUE;
  }
  return FALSE;
}

bool_t
xdr_int64_t (XDR *xdrs, int64_t *qp)
{
  return xdr_u_int64_t (xdrs, (u_int64_t *) qp);
}
