1 /* simple.c -- BFD simple client routines 2 Copyright (C) 2002-2014 Free Software Foundation, Inc. 3 Contributed by MontaVista Software, Inc. 4 5 This file is part of BFD, the Binary File Descriptor library. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 20 MA 02110-1301, USA. */ 21 22 #include "sysdep.h" 23 #include "bfd.h" 24 #include "libbfd.h" 25 #include "bfdlink.h" 26 27 static bfd_boolean 28 simple_dummy_warning (struct bfd_link_info *link_info ATTRIBUTE_UNUSED, 29 const char *warning ATTRIBUTE_UNUSED, 30 const char *symbol ATTRIBUTE_UNUSED, 31 bfd *abfd ATTRIBUTE_UNUSED, 32 asection *section ATTRIBUTE_UNUSED, 33 bfd_vma address ATTRIBUTE_UNUSED) 34 { 35 return TRUE; 36 } 37 38 static bfd_boolean 39 simple_dummy_undefined_symbol (struct bfd_link_info *link_info ATTRIBUTE_UNUSED, 40 const char *name ATTRIBUTE_UNUSED, 41 bfd *abfd ATTRIBUTE_UNUSED, 42 asection *section ATTRIBUTE_UNUSED, 43 bfd_vma address ATTRIBUTE_UNUSED, 44 bfd_boolean fatal ATTRIBUTE_UNUSED) 45 { 46 return TRUE; 47 } 48 49 static bfd_boolean 50 simple_dummy_reloc_overflow (struct bfd_link_info *link_info ATTRIBUTE_UNUSED, 51 struct bfd_link_hash_entry *entry ATTRIBUTE_UNUSED, 52 const char *name ATTRIBUTE_UNUSED, 53 const char *reloc_name ATTRIBUTE_UNUSED, 54 bfd_vma addend ATTRIBUTE_UNUSED, 55 bfd *abfd ATTRIBUTE_UNUSED, 56 asection *section ATTRIBUTE_UNUSED, 57 bfd_vma address ATTRIBUTE_UNUSED) 58 { 59 return TRUE; 60 } 61 62 static bfd_boolean 63 simple_dummy_reloc_dangerous (struct bfd_link_info *link_info ATTRIBUTE_UNUSED, 64 const char *message ATTRIBUTE_UNUSED, 65 bfd *abfd ATTRIBUTE_UNUSED, 66 asection *section ATTRIBUTE_UNUSED, 67 bfd_vma address ATTRIBUTE_UNUSED) 68 { 69 return TRUE; 70 } 71 72 static bfd_boolean 73 simple_dummy_unattached_reloc (struct bfd_link_info *link_info ATTRIBUTE_UNUSED, 74 const char *name ATTRIBUTE_UNUSED, 75 bfd *abfd ATTRIBUTE_UNUSED, 76 asection *section ATTRIBUTE_UNUSED, 77 bfd_vma address ATTRIBUTE_UNUSED) 78 { 79 return TRUE; 80 } 81 82 static bfd_boolean 83 simple_dummy_multiple_definition (struct bfd_link_info *link_info ATTRIBUTE_UNUSED, 84 struct bfd_link_hash_entry *h ATTRIBUTE_UNUSED, 85 bfd *nbfd ATTRIBUTE_UNUSED, 86 asection *nsec ATTRIBUTE_UNUSED, 87 bfd_vma nval ATTRIBUTE_UNUSED) 88 { 89 return TRUE; 90 } 91 92 static void 93 simple_dummy_einfo (const char *fmt ATTRIBUTE_UNUSED, ...) 94 { 95 } 96 97 struct saved_output_info 98 { 99 bfd_vma offset; 100 asection *section; 101 }; 102 103 struct saved_offsets 104 { 105 int section_count; 106 struct saved_output_info *sections; 107 }; 108 109 /* The sections in ABFD may already have output sections and offsets 110 set if we are here during linking. 111 112 DWARF-2 specifies offsets into debug sections in many cases and 113 bfd_simple_get_relocated_section_contents is called to relocate 114 debug info for a single relocatable object file. So we want 115 offsets relative to that object file's sections, not offsets in the 116 output file. For that reason, reset a debug section->output_offset 117 to zero. 118 119 If not called during linking then set section->output_section to 120 point back to the input section, because output_section must not be 121 NULL when calling the relocation routines. 122 123 Save the original output offset and section to restore later. */ 124 125 static void 126 simple_save_output_info (bfd *abfd ATTRIBUTE_UNUSED, 127 asection *section, 128 void *ptr) 129 { 130 struct saved_offsets *saved_offsets = (struct saved_offsets *) ptr; 131 struct saved_output_info *output_info; 132 133 output_info = &saved_offsets->sections[section->index]; 134 output_info->offset = section->output_offset; 135 output_info->section = section->output_section; 136 if ((section->flags & SEC_DEBUGGING) != 0 137 || section->output_section == NULL) 138 { 139 section->output_offset = 0; 140 section->output_section = section; 141 } 142 } 143 144 static void 145 simple_restore_output_info (bfd *abfd ATTRIBUTE_UNUSED, 146 asection *section, 147 void *ptr) 148 { 149 struct saved_offsets *saved_offsets = (struct saved_offsets *) ptr; 150 struct saved_output_info *output_info; 151 152 if (section->index >= saved_offsets->section_count) 153 return; 154 155 output_info = &saved_offsets->sections[section->index]; 156 section->output_offset = output_info->offset; 157 section->output_section = output_info->section; 158 } 159 160 /* 161 FUNCTION 162 bfd_simple_relocate_secton 163 164 SYNOPSIS 165 bfd_byte *bfd_simple_get_relocated_section_contents 166 (bfd *abfd, asection *sec, bfd_byte *outbuf, asymbol **symbol_table); 167 168 DESCRIPTION 169 Returns the relocated contents of section @var{sec}. The symbols in 170 @var{symbol_table} will be used, or the symbols from @var{abfd} if 171 @var{symbol_table} is NULL. The output offsets for debug sections will 172 be temporarily reset to 0. The result will be stored at @var{outbuf} 173 or allocated with @code{bfd_malloc} if @var{outbuf} is @code{NULL}. 174 175 Returns @code{NULL} on a fatal error; ignores errors applying 176 particular relocations. 177 */ 178 179 bfd_byte * 180 bfd_simple_get_relocated_section_contents (bfd *abfd, 181 asection *sec, 182 bfd_byte *outbuf, 183 asymbol **symbol_table) 184 { 185 struct bfd_link_info link_info; 186 struct bfd_link_order link_order; 187 struct bfd_link_callbacks callbacks; 188 bfd_byte *contents, *data; 189 int storage_needed; 190 struct saved_offsets saved_offsets; 191 bfd *link_next; 192 193 /* Don't apply relocation on executable and shared library. See 194 PR 4756. */ 195 if ((abfd->flags & (HAS_RELOC | EXEC_P | DYNAMIC)) != HAS_RELOC 196 || ! (sec->flags & SEC_RELOC)) 197 { 198 contents = outbuf; 199 if (!bfd_get_full_section_contents (abfd, sec, &contents)) 200 return NULL; 201 return contents; 202 } 203 204 /* In order to use bfd_get_relocated_section_contents, we need 205 to forge some data structures that it expects. */ 206 207 /* Fill in the bare minimum number of fields for our purposes. */ 208 memset (&link_info, 0, sizeof (link_info)); 209 link_info.output_bfd = abfd; 210 link_info.input_bfds = abfd; 211 link_info.input_bfds_tail = &abfd->link.next; 212 213 link_next = abfd->link.next; 214 abfd->link.next = NULL; 215 link_info.hash = _bfd_generic_link_hash_table_create (abfd); 216 link_info.callbacks = &callbacks; 217 callbacks.warning = simple_dummy_warning; 218 callbacks.undefined_symbol = simple_dummy_undefined_symbol; 219 callbacks.reloc_overflow = simple_dummy_reloc_overflow; 220 callbacks.reloc_dangerous = simple_dummy_reloc_dangerous; 221 callbacks.unattached_reloc = simple_dummy_unattached_reloc; 222 callbacks.multiple_definition = simple_dummy_multiple_definition; 223 callbacks.einfo = simple_dummy_einfo; 224 225 memset (&link_order, 0, sizeof (link_order)); 226 link_order.next = NULL; 227 link_order.type = bfd_indirect_link_order; 228 link_order.offset = 0; 229 link_order.size = sec->size; 230 link_order.u.indirect.section = sec; 231 232 data = NULL; 233 if (outbuf == NULL) 234 { 235 bfd_size_type amt = sec->rawsize > sec->size ? sec->rawsize : sec->size; 236 data = (bfd_byte *) bfd_malloc (amt); 237 if (data == NULL) 238 { 239 _bfd_generic_link_hash_table_free (abfd); 240 abfd->link.next = link_next; 241 return NULL; 242 } 243 outbuf = data; 244 } 245 246 saved_offsets.section_count = abfd->section_count; 247 saved_offsets.sections = malloc (sizeof (*saved_offsets.sections) 248 * saved_offsets.section_count); 249 if (saved_offsets.sections == NULL) 250 { 251 if (data) 252 free (data); 253 _bfd_generic_link_hash_table_free (abfd); 254 abfd->link.next = link_next; 255 return NULL; 256 } 257 bfd_map_over_sections (abfd, simple_save_output_info, &saved_offsets); 258 259 if (symbol_table == NULL) 260 { 261 _bfd_generic_link_add_symbols (abfd, &link_info); 262 263 storage_needed = bfd_get_symtab_upper_bound (abfd); 264 symbol_table = (asymbol **) bfd_malloc (storage_needed); 265 bfd_canonicalize_symtab (abfd, symbol_table); 266 } 267 else 268 storage_needed = 0; 269 270 contents = bfd_get_relocated_section_contents (abfd, 271 &link_info, 272 &link_order, 273 outbuf, 274 0, 275 symbol_table); 276 if (contents == NULL && data != NULL) 277 free (data); 278 279 bfd_map_over_sections (abfd, simple_restore_output_info, &saved_offsets); 280 free (saved_offsets.sections); 281 282 _bfd_generic_link_hash_table_free (abfd); 283 abfd->link.next = link_next; 284 return contents; 285 } 286