1/* Create new ELF program header table.
2   Copyright (C) 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 <stdlib.h>
57#include <string.h>
58
59#include "libelfP.h"
60
61#ifndef LIBELFBITS
62# define LIBELFBITS 32
63#endif
64
65
66ElfW2(LIBELFBITS,Phdr) *
67elfw2(LIBELFBITS,newphdr) (elf, count)
68     Elf *elf;
69     size_t count;
70{
71  ElfW2(LIBELFBITS,Phdr) *result;
72
73  if (elf == NULL)
74    return NULL;
75
76  if (unlikely (elf->kind != ELF_K_ELF))
77    {
78      __libelf_seterrno (ELF_E_INVALID_HANDLE);
79      return NULL;
80    }
81
82  rwlock_wrlock (elf->lock);
83
84  if (elf->class == 0)
85    elf->class = ELFW(ELFCLASS,LIBELFBITS);
86  else if (unlikely (elf->class != ELFW(ELFCLASS,LIBELFBITS)))
87    {
88      __libelf_seterrno (ELF_E_INVALID_CLASS);
89      result = NULL;
90      goto out;
91    }
92
93  if (unlikely (elf->state.ELFW(elf,LIBELFBITS).ehdr == NULL))
94    {
95      __libelf_seterrno (ELF_E_WRONG_ORDER_EHDR);
96      result = NULL;
97      goto out;
98    }
99
100  /* A COUNT of zero means remove existing table.  */
101  if (count == 0)
102    {
103      /* Free the old program header.  */
104      if (elf->state.ELFW(elf,LIBELFBITS).phdr != NULL)
105	{
106	  if (elf->state.ELFW(elf,LIBELFBITS).phdr_flags & ELF_F_MALLOCED)
107	    free (elf->state.ELFW(elf,LIBELFBITS).phdr);
108
109	  /* Set the pointer to NULL.  */
110	  elf->state.ELFW(elf,LIBELFBITS).phdr = NULL;
111	  /* Set the `e_phnum' member to the new value.  */
112	  elf->state.ELFW(elf,LIBELFBITS).ehdr->e_phnum = 0;
113	  /* Also set the size.  */
114	  elf->state.ELFW(elf,LIBELFBITS).ehdr->e_phentsize =
115	    sizeof (ElfW2(LIBELFBITS,Phdr));
116
117	  elf->state.ELFW(elf,LIBELFBITS).phdr_flags |= ELF_F_DIRTY;
118	  elf->flags |= ELF_F_DIRTY;
119	  __libelf_seterrno (ELF_E_NOERROR);
120	}
121
122      result = NULL;
123    }
124  else if (elf->state.ELFW(elf,LIBELFBITS).ehdr->e_phnum != count
125	   || elf->state.ELFW(elf,LIBELFBITS).phdr == NULL)
126    {
127      /* Allocate a new program header with the appropriate number of
128	 elements.  */
129      result = (ElfW2(LIBELFBITS,Phdr) *)
130	realloc (elf->state.ELFW(elf,LIBELFBITS).phdr,
131		 count * sizeof (ElfW2(LIBELFBITS,Phdr)));
132      if (result == NULL)
133	__libelf_seterrno (ELF_E_NOMEM);
134      else
135	{
136	  /* Now set the result.  */
137	  elf->state.ELFW(elf,LIBELFBITS).phdr = result;
138	  /* Clear the whole memory.  */
139	  memset (result, '\0', count * sizeof (ElfW2(LIBELFBITS,Phdr)));
140	  /* Set the `e_phnum' member to the new value.  */
141	  elf->state.ELFW(elf,LIBELFBITS).ehdr->e_phnum = count;
142	  /* Also set the size.  */
143	  elf->state.ELFW(elf,LIBELFBITS).ehdr->e_phentsize =
144	    elf_typesize (LIBELFBITS, ELF_T_PHDR, 1);
145	  /* Remember we allocated the array and mark the structure is
146	     modified.  */
147	  elf->state.ELFW(elf,LIBELFBITS).phdr_flags |=
148	    ELF_F_DIRTY | ELF_F_MALLOCED;
149	  /* We have to rewrite the entire file if the size of the
150	     program header is changed.  */
151	  elf->flags |= ELF_F_DIRTY;
152	}
153    }
154  else
155    {
156      /* We have the same number of entries.  Just clear the array.  */
157      assert (elf->state.ELFW(elf,LIBELFBITS).ehdr->e_phentsize
158	      == elf_typesize (LIBELFBITS, ELF_T_PHDR, 1));
159
160      /* Mark the structure as modified.  */
161      elf->state.ELFW(elf,LIBELFBITS).phdr_flags |= ELF_F_DIRTY;
162
163      result = elf->state.ELFW(elf,LIBELFBITS).phdr;
164    }
165
166 out:
167  rwlock_unlock (elf->lock);
168
169  return result;
170}
171INTDEF(elfw2(LIBELFBITS,newphdr))
172