sunrpc/xdr_ref.c

   1 /*
   2  * xdr_reference.c, Generic XDR routines implementation.
   3  *
   4  * Copyright (c) 2010, Oracle America, Inc.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are
   8  * met:
   9  *
  10  *     * Redistributions of source code must retain the above copyright
  11  *       notice, this list of conditions and the following disclaimer.
  12  *     * Redistributions in binary form must reproduce the above
  13  *       copyright notice, this list of conditions and the following
  14  *       disclaimer in the documentation and/or other materials
  15  *       provided with the distribution.
  16  *     * Neither the name of the "Oracle America, Inc." nor the names of its
  17  *       contributors may be used to endorse or promote products derived
  18  *       from this software without specific prior written permission.
  19  *
  20  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  24  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  25  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  27  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  28  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  29  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  *
  33  * These are the "non-trivial" xdr primitives used to serialize and
  34  * de-serialize "pointers".  See xdr.h for more info on the interface to xdr.
  35  */
  36
  37 #include <stdio.h>
  38 #include <string.h>
  39 #include <rpc/types.h>
  40 #include <rpc/xdr.h>
  41 #include <libintl.h>
  42
  43 #ifdef USE_IN_LIBIO
  44 # include <wchar.h>
  45 # include <libio/iolibio.h>
  46 #endif
  47
  48 #define LASTUNSIGNED    ((u_int)0-1)
  49
  50 /*
  51  * XDR an indirect pointer
  52  * xdr_reference is for recursively translating a structure that is
  53  * referenced by a pointer inside the structure that is currently being
  54  * translated.  pp references a pointer to storage. If *pp is null
  55  * the  necessary storage is allocated.
  56  * size is the size of the referneced structure.
  57  * proc is the routine to handle the referenced structure.
  58  */
  59 bool_t
  60 xdr_reference (xdrs, pp, size, proc)
  61      XDR *xdrs;
  62      caddr_t *pp;               /* the pointer to work on */
  63      u_int size;                /* size of the object pointed to */
  64      xdrproc_t proc;            /* xdr routine to handle the object */
  65 {
  66   caddr_t loc = *pp;
  67   bool_t stat;
  68
  69   if (loc == NULL)
  70     switch (xdrs->x_op)
  71       {
  72       case XDR_FREE:
  73         return TRUE;
  74
  75       case XDR_DECODE:
  76         *pp = loc = (caddr_t) calloc (1, size);
  77         if (loc == NULL)
  78           {
  79             (void) __fxprintf (NULL, "%s: %s", __func__, _("out of memory\n"));
  80             return FALSE;
  81           }
  82         break;
  83       default:
  84         break;
  85       }
  86
  87   stat = (*proc) (xdrs, loc, LASTUNSIGNED);
  88
  89   if (xdrs->x_op == XDR_FREE)
  90     {
  91       mem_free (loc, size);
  92       *pp = NULL;
  93     }
  94   return stat;
  95 }
  96 INTDEF(xdr_reference)
  97
  98
  99 /*
 100  * xdr_pointer():
 101  *
 102  * XDR a pointer to a possibly recursive data structure. This
 103  * differs with xdr_reference in that it can serialize/deserialize
 104  * trees correctly.
 105  *
 106  *  What's sent is actually a union:
 107  *
 108  *  union object_pointer switch (boolean b) {
 109  *  case TRUE: object_data data;
 110  *  case FALSE: void nothing;
 111  *  }
 112  *
 113  * > objpp: Pointer to the pointer to the object.
 114  * > obj_size: size of the object.
 115  * > xdr_obj: routine to XDR an object.
 116  *
 117  */
 118 bool_t
 119 xdr_pointer (xdrs, objpp, obj_size, xdr_obj)
 120      XDR *xdrs;
 121      char **objpp;
 122      u_int obj_size;
 123      xdrproc_t xdr_obj;
 124 {
 125
 126   bool_t more_data;
 127
 128   more_data = (*objpp != NULL);
 129   if (!INTUSE(xdr_bool) (xdrs, &more_data))
 130     {
 131       return FALSE;
 132     }
 133   if (!more_data)
 134     {
 135       *objpp = NULL;
 136       return TRUE;
 137     }
 138   return INTUSE(xdr_reference) (xdrs, objpp, obj_size, xdr_obj);
 139 }