1/* Convert from memory to file representation.
2   Copyright (C) 1998, 1999, 2000, 2002 Red Hat, Inc.
3   This file is part of Red Hat elfutils.
4   Written by Ulrich Drepper <drepper@redhat.com>, 1998.
5
6   Red Hat elfutils is free software; you can redistribute it and/or modify
7   it under the terms of the GNU General Public License as published by the
8   Free Software Foundation; version 2 of the License.
9
10   Red Hat elfutils is distributed in the hope that it will be useful, but
11   WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   General Public License for more details.
14
15   You should have received a copy of the GNU General Public License along
16   with Red Hat elfutils; if not, write to the Free Software Foundation,
17   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
18
19   In addition, as a special exception, Red Hat, Inc. gives You the
20   additional right to link the code of Red Hat elfutils with code licensed
21   under any Open Source Initiative certified open source license
22   (http://www.opensource.org/licenses/index.php) which requires the
23   distribution of source code with any binary distribution and to
24   distribute linked combinations of the two.  Non-GPL Code permitted under
25   this exception must only link to the code of Red Hat elfutils through
26   those well defined interfaces identified in the file named EXCEPTION
27   found in the source code files (the "Approved Interfaces").  The files
28   of Non-GPL Code may instantiate templates or use macros or inline
29   functions from the Approved Interfaces without causing the resulting
30   work to be covered by the GNU General Public License.  Only Red Hat,
31   Inc. may make changes or additions to the list of Approved Interfaces.
32   Red Hat's grant of this exception is conditioned upon your not adding
33   any new exceptions.  If you wish to add a new Approved Interface or
34   exception, please contact Red Hat.  You must obey the GNU General Public
35   License in all respects for all of the Red Hat elfutils code and other
36   code used in conjunction with Red Hat elfutils except the Non-GPL Code
37   covered by this exception.  If you modify this file, you may extend this
38   exception to your version of the file, but you are not obligated to do
39   so.  If you do not wish to provide this exception without modification,
40   you must delete this exception statement from your version and license
41   this file solely under the GPL without exception.
42
43   Red Hat elfutils is an included package of the Open Invention Network.
44   An included package of the Open Invention Network is a package for which
45   Open Invention Network licensees cross-license their patents.  No patent
46   license is granted, either expressly or impliedly, by designation as an
47   included package.  Should you wish to participate in the Open Invention
48   Network licensing program, please visit www.openinventionnetwork.com
49   <http://www.openinventionnetwork.com>.  */
50
51#ifdef HAVE_CONFIG_H
52# include <config.h>
53#endif
54
55#include <assert.h>
56#include <endian.h>
57#include <string.h>
58
59#include "libelfP.h"
60
61#ifndef LIBELFBITS
62# define LIBELFBITS	32
63#endif
64
65
66Elf_Data *
67elfw2(LIBELFBITS, xlatetof) (dest, src, encode)
68     Elf_Data *dest;
69     const Elf_Data *src;
70     unsigned int encode;
71{
72  /* First test whether the input data is really suitable for this
73     type.  This means, whether there is an integer number of records.
74     Note that for this implementation the memory and file size of the
75     data types are identical.  */
76#if EV_NUM != 2
77  size_t recsize = __libelf_type_sizes[src->d_version - 1][ELFW(ELFCLASS,LIBELFBITS) - 1][src->d_type];
78#else
79  size_t recsize = __libelf_type_sizes[0][ELFW(ELFCLASS,LIBELFBITS) - 1][src->d_type];
80#endif
81
82  if (src->d_size % recsize != 0)
83    {
84      __libelf_seterrno (ELF_E_INVALID_DATA);
85      return NULL;
86    }
87
88  /* Next see whether the converted data fits in the output buffer.  */
89  if (src->d_size > dest->d_size)
90    {
91      __libelf_seterrno (ELF_E_DEST_SIZE);
92      return NULL;
93    }
94
95  /* Test the encode parameter.  */
96  if (encode != ELFDATA2LSB && encode != ELFDATA2MSB)
97    {
98      __libelf_seterrno (ELF_E_INVALID_ENCODING);
99      return NULL;
100    }
101
102  /* Determine the translation function to use.
103
104     At this point we make an assumption which is valid for all
105     existing implementations so far: the memory and file sizes are
106     the same.  This has very important consequences:
107     a) The requirement that the source and destination buffer can
108	overlap can easily be fulfilled.
109     b) We need only one function to convert from and memory to file
110	and vice versa since the function only has to copy and/or
111	change the byte order.
112  */
113  if ((__BYTE_ORDER == __LITTLE_ENDIAN && encode == ELFDATA2LSB)
114      || (__BYTE_ORDER == __BIG_ENDIAN && encode == ELFDATA2MSB))
115    {
116      /* We simply have to copy since the byte order is the same.  */
117      if (src->d_buf != dest->d_buf)
118	memmove (dest->d_buf, src->d_buf, src->d_size);
119    }
120  else
121    {
122      xfct_t fctp;
123
124      /* Get a pointer to the transformation functions.  The `#ifdef' is
125	 a small optimization since we don't anticipate another ELF
126	 version and so would waste "precious" code.  */
127#if EV_NUM != 2
128      fctp = __elf_xfctstom[dest->d_version - 1][src->d_version - 1][ELFW(ELFCLASS, LIBELFBITS) - 1][src->d_type];
129#else
130      fctp = __elf_xfctstom[0][0][ELFW(ELFCLASS, LIBELFBITS) - 1][src->d_type];
131#endif
132
133      /* Do the real work.  */
134      (*fctp) (dest->d_buf, src->d_buf, src->d_size, 1);
135    }
136
137  /* Now set the real destination type and length since the operation was
138     successful.  */
139  dest->d_type = src->d_type;
140  dest->d_size = src->d_size;
141
142  return dest;
143}
144INTDEF(elfw2(LIBELFBITS, xlatetof))
145