glibc/sunrpc/xdr_mem.c
2011-04-16 21:59:36 -04:00

241 lines
6.6 KiB
C

/*
* xdr_mem.c, XDR implementation using memory buffers.
*
* Copyright (c) 2010, Oracle America, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
* * Neither the name of the "Oracle America, Inc." nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* If you have some data to be interpreted as external data representation
* or to be converted to external data representation in a memory buffer,
* then this is the package for you.
*/
#include <string.h>
#include <limits.h>
#include <rpc/rpc.h>
static bool_t xdrmem_getlong (XDR *, long *);
static bool_t xdrmem_putlong (XDR *, const long *);
static bool_t xdrmem_getbytes (XDR *, caddr_t, u_int);
static bool_t xdrmem_putbytes (XDR *, const char *, u_int);
static u_int xdrmem_getpos (const XDR *);
static bool_t xdrmem_setpos (XDR *, u_int);
static int32_t *xdrmem_inline (XDR *, u_int);
static void xdrmem_destroy (XDR *);
static bool_t xdrmem_getint32 (XDR *, int32_t *);
static bool_t xdrmem_putint32 (XDR *, const int32_t *);
static const struct xdr_ops xdrmem_ops =
{
xdrmem_getlong,
xdrmem_putlong,
xdrmem_getbytes,
xdrmem_putbytes,
xdrmem_getpos,
xdrmem_setpos,
xdrmem_inline,
xdrmem_destroy,
xdrmem_getint32,
xdrmem_putint32
};
/*
* The procedure xdrmem_create initializes a stream descriptor for a
* memory buffer.
*/
void
xdrmem_create (XDR *xdrs, const caddr_t addr, u_int size, enum xdr_op op)
{
xdrs->x_op = op;
/* We have to add the const since the `struct xdr_ops' in `struct XDR'
is not `const'. */
xdrs->x_ops = (struct xdr_ops *) &xdrmem_ops;
xdrs->x_private = xdrs->x_base = addr;
xdrs->x_handy = size;
}
#ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def (xdrmem_create)
#else
libc_hidden_nolink (xdrmem_create, GLIBC_2_0)
#endif
/*
* Nothing needs to be done for the memory case. The argument is clearly
* const.
*/
static void
xdrmem_destroy (XDR *xdrs)
{
}
/*
* Gets the next word from the memory referenced by xdrs and places it
* in the long pointed to by lp. It then increments the private word to
* point at the next element. Neither object pointed to is const
*/
static bool_t
xdrmem_getlong (XDR *xdrs, long *lp)
{
if (xdrs->x_handy < 4)
return FALSE;
xdrs->x_handy -= 4;
*lp = (int32_t) ntohl ((*((int32_t *) (xdrs->x_private))));
xdrs->x_private += 4;
return TRUE;
}
/*
* Puts the long pointed to by lp in the memory referenced by xdrs. It
* then increments the private word to point at the next element. The
* long pointed at is const
*/
static bool_t
xdrmem_putlong (XDR *xdrs, const long *lp)
{
if (xdrs->x_handy < 4)
return FALSE;
xdrs->x_handy -= 4;
*(int32_t *) xdrs->x_private = htonl (*lp);
xdrs->x_private += 4;
return TRUE;
}
/*
* Gets an unaligned number of bytes from the xdrs structure and writes them
* to the address passed in addr. Be very careful when calling this routine
* as it could leave the xdrs pointing to an unaligned structure which is not
* a good idea. None of the things pointed to are const.
*/
static bool_t
xdrmem_getbytes (XDR *xdrs, caddr_t addr, u_int len)
{
if (xdrs->x_handy < len)
return FALSE;
xdrs->x_handy -= len;
memcpy (addr, xdrs->x_private, len);
xdrs->x_private += len;
return TRUE;
}
/*
* The complementary function to the above. The same warnings apply about
* unaligned data. The source address is const.
*/
static bool_t
xdrmem_putbytes (XDR *xdrs, const char *addr, u_int len)
{
if (xdrs->x_handy < len)
return FALSE;
xdrs->x_handy -= len;
memcpy (xdrs->x_private, addr, len);
xdrs->x_private += len;
return TRUE;
}
/*
* Not sure what this one does. But it clearly doesn't modify the contents
* of xdrs. **FIXME** does this not assume u_int == u_long?
*/
static u_int
xdrmem_getpos (const XDR *xdrs)
{
return (u_long) xdrs->x_private - (u_long) xdrs->x_base;
}
/*
* xdrs modified
*/
static bool_t
xdrmem_setpos (xdrs, pos)
XDR *xdrs;
u_int pos;
{
caddr_t newaddr = xdrs->x_base + pos;
caddr_t lastaddr = xdrs->x_private + xdrs->x_handy;
size_t handy = lastaddr - newaddr;
if (newaddr > lastaddr
|| newaddr < xdrs->x_base
|| handy != (u_int) handy)
return FALSE;
xdrs->x_private = newaddr;
xdrs->x_handy = (u_int) handy;
return TRUE;
}
/*
* xdrs modified
*/
static int32_t *
xdrmem_inline (XDR *xdrs, u_int len)
{
int32_t *buf = 0;
if (xdrs->x_handy >= len)
{
xdrs->x_handy -= len;
buf = (int32_t *) xdrs->x_private;
xdrs->x_private += len;
}
return buf;
}
/*
* Gets the next word from the memory referenced by xdrs and places it
* in the int pointed to by ip. It then increments the private word to
* point at the next element. Neither object pointed to is const
*/
static bool_t
xdrmem_getint32 (XDR *xdrs, int32_t *ip)
{
if (xdrs->x_handy < 4)
return FALSE;
xdrs->x_handy -= 4;
*ip = ntohl ((*((int32_t *) (xdrs->x_private))));
xdrs->x_private += 4;
return TRUE;
}
/*
* Puts the long pointed to by lp in the memory referenced by xdrs. It
* then increments the private word to point at the next element. The
* long pointed at is const
*/
static bool_t
xdrmem_putint32 (XDR *xdrs, const int32_t *ip)
{
if (xdrs->x_handy < 4)
return FALSE;
xdrs->x_handy -= 4;
*(int32_t *) xdrs->x_private = htonl (*ip);
xdrs->x_private += 4;
return TRUE;
}