lib/libspl/xdr.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  *
  22  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  *
  25  *      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T
  26  *        All Rights Reserved
  27  *
  28  * Portions of this source code were derived from Berkeley 4.3 BSD
  29  * under license from the Regents of the University of California.
  30  */
  31
  32 #include <rpc/xdr.h>
  33
  34 /*
  35  * As of glibc-2.5-25 there is not support for xdr_control().  The
  36  * xdrmem implementation from OpenSolaris is used here.
  37  *
  38  * FIXME: Not well tested it may not work as expected.
  39  */
  40 bool_t
  41 xdr_control(XDR *xdrs, int request, void *info)
  42 {
  43         xdr_bytesrec_t *xptr;
  44         int32_t *int32p;
  45         int len;
  46
  47         switch (request) {
  48         case XDR_GET_BYTES_AVAIL:
  49                 xptr = (xdr_bytesrec_t *)info;
  50                 xptr->xc_is_last_record = TRUE;
  51                 xptr->xc_num_avail = xdrs->x_handy;
  52                 return (TRUE);
  53
  54         case XDR_PEEK:
  55                 /*
  56                  * Return the next 4 byte unit in the XDR stream.
  57                  */
  58                 if (xdrs->x_handy < sizeof (int32_t))
  59                         return (FALSE);
  60                 int32p = (int32_t *)info;
  61                 *int32p = (int32_t)ntohl((uint32_t)
  62                     (*((int32_t *)(xdrs->x_private))));
  63                 return (TRUE);
  64
  65         case XDR_SKIPBYTES:
  66                 /*
  67                  * Skip the next N bytes in the XDR stream.
  68                  */
  69                 int32p = (int32_t *)info;
  70                 len = RNDUP((int)(*int32p));
  71                 if ((xdrs->x_handy -= len) < 0)
  72                         return (FALSE);
  73                 xdrs->x_private += len;
  74                 return (TRUE);
  75
  76         }
  77         return (FALSE);
  78 }