Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 1 | /* Append new section. |
| 2 | Copyright (C) 1998, 1999, 2000, 2001, 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 <stdbool.h> |
| 57 | #include <stddef.h> |
| 58 | #include <stdlib.h> |
| 59 | #include <string.h> |
| 60 | |
| 61 | #include "libelfP.h" |
| 62 | |
| 63 | |
| 64 | Elf_Scn * |
| 65 | elf_newscn (elf) |
| 66 | Elf *elf; |
| 67 | { |
| 68 | Elf_Scn *result = NULL; |
| 69 | bool first = false; |
| 70 | |
| 71 | if (elf == NULL) |
| 72 | return NULL; |
| 73 | |
| 74 | /* We rely on the prefix of the `elf', `elf32', and `elf64' element |
| 75 | being the same. */ |
| 76 | assert (offsetof (Elf, state.elf.scns_last) |
| 77 | == offsetof (Elf, state.elf32.scns_last)); |
| 78 | assert (offsetof (Elf, state.elf.scns_last) |
| 79 | == offsetof (Elf, state.elf64.scns_last)); |
| 80 | assert (offsetof (Elf, state.elf32.scns) |
| 81 | == offsetof (Elf, state.elf64.scns)); |
| 82 | |
| 83 | rwlock_wrlock (elf->lock); |
| 84 | |
| 85 | again: |
| 86 | if (elf->state.elf.scns_last->cnt < elf->state.elf.scns_last->max) |
| 87 | { |
| 88 | result = &elf->state.elf.scns_last->data[elf->state.elf.scns_last->cnt]; |
| 89 | |
| 90 | if (++elf->state.elf.scns_last->cnt == 1 |
| 91 | && (elf->state.elf.scns_last |
| 92 | == (elf->class == ELFCLASS32 |
| 93 | || (offsetof (Elf, state.elf32.scns) |
| 94 | == offsetof (Elf, state.elf64.scns)) |
| 95 | ? &elf->state.elf32.scns : &elf->state.elf64.scns))) |
| 96 | /* This is zeroth section. */ |
| 97 | first = true; |
| 98 | else |
| 99 | { |
| 100 | assert (elf->state.elf.scns_last->cnt > 1); |
| 101 | result->index = result[-1].index + 1; |
| 102 | } |
| 103 | } |
| 104 | else |
| 105 | { |
| 106 | /* We must allocate a new element. */ |
| 107 | Elf_ScnList *newp; |
| 108 | |
| 109 | assert (elf->state.elf.scnincr > 0); |
| 110 | |
| 111 | newp = (Elf_ScnList *) calloc (sizeof (Elf_ScnList) |
| 112 | + ((elf->state.elf.scnincr *= 2) |
| 113 | * sizeof (Elf_Scn)), 1); |
| 114 | if (newp == NULL) |
| 115 | { |
| 116 | __libelf_seterrno (ELF_E_NOMEM); |
| 117 | goto out; |
| 118 | } |
| 119 | |
| 120 | result = &newp->data[0]; |
| 121 | |
| 122 | /* One section used. */ |
| 123 | ++newp->cnt; |
| 124 | |
| 125 | /* This is the number of sections we allocated. */ |
| 126 | newp->max = elf->state.elf.scnincr; |
| 127 | |
| 128 | /* Remember the index for the first section in this block. */ |
| 129 | newp->data[0].index |
| 130 | = 1 + elf->state.elf.scns_last->data[elf->state.elf.scns_last->max - 1].index; |
| 131 | |
| 132 | /* Enqueue the new list element. */ |
| 133 | elf->state.elf.scns_last = elf->state.elf.scns_last->next = newp; |
| 134 | } |
| 135 | |
| 136 | /* Create a section header for this section. */ |
| 137 | if (elf->class == ELFCLASS32) |
| 138 | { |
| 139 | result->shdr.e32 = (Elf32_Shdr *) calloc (1, sizeof (Elf32_Shdr)); |
| 140 | if (result->shdr.e32 == NULL) |
| 141 | { |
| 142 | __libelf_seterrno (ELF_E_NOMEM); |
| 143 | goto out; |
| 144 | } |
| 145 | } |
| 146 | else |
| 147 | { |
| 148 | result->shdr.e64 = (Elf64_Shdr *) calloc (1, sizeof (Elf64_Shdr)); |
| 149 | if (result->shdr.e64 == NULL) |
| 150 | { |
| 151 | __libelf_seterrno (ELF_E_NOMEM); |
| 152 | goto out; |
| 153 | } |
| 154 | } |
| 155 | |
| 156 | result->elf = elf; |
| 157 | result->shdr_flags = ELF_F_DIRTY | ELF_F_MALLOCED; |
| 158 | result->list = elf->state.elf.scns_last; |
| 159 | |
| 160 | /* Initialize the data part. */ |
| 161 | result->data_read = 1; |
| 162 | if (unlikely (first)) |
| 163 | { |
| 164 | /* For the first section we mark the data as already available. */ |
| 165 | //result->data_list_rear = &result->data_list; |
| 166 | first = false; |
| 167 | goto again; |
| 168 | } |
| 169 | |
| 170 | result->flags |= ELF_F_DIRTY; |
| 171 | |
| 172 | out: |
| 173 | rwlock_unlock (elf->lock); |
| 174 | |
| 175 | return result; |
| 176 | } |