| 1 | // dynobj.cc -- dynamic object support for gold |
| 2 | |
| 3 | // Copyright (C) 2006-2019 Free Software Foundation, Inc. |
| 4 | // Written by Ian Lance Taylor <iant@google.com>. |
| 5 | |
| 6 | // This file is part of gold. |
| 7 | |
| 8 | // This program is free software; you can redistribute it and/or modify |
| 9 | // it under the terms of the GNU General Public License as published by |
| 10 | // the Free Software Foundation; either version 3 of the License, or |
| 11 | // (at your option) any later version. |
| 12 | |
| 13 | // This program is distributed in the hope that it will be useful, |
| 14 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | // GNU General Public License for more details. |
| 17 | |
| 18 | // You should have received a copy of the GNU General Public License |
| 19 | // along with this program; if not, write to the Free Software |
| 20 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, |
| 21 | // MA 02110-1301, USA. |
| 22 | |
| 23 | #include "gold.h" |
| 24 | |
| 25 | #include <vector> |
| 26 | #include <cstring> |
| 27 | |
| 28 | #include "elfcpp.h" |
| 29 | #include "parameters.h" |
| 30 | #include "script.h" |
| 31 | #include "symtab.h" |
| 32 | #include "dynobj.h" |
| 33 | |
| 34 | namespace gold |
| 35 | { |
| 36 | |
| 37 | // Class Dynobj. |
| 38 | |
| 39 | // Sets up the default soname_ to use, in the (rare) cases we never |
| 40 | // see a DT_SONAME entry. |
| 41 | |
| 42 | Dynobj::Dynobj(const std::string& name, Input_file* input_file, off_t offset) |
| 43 | : Object(name, input_file, true, offset), |
| 44 | needed_(), |
| 45 | unknown_needed_(UNKNOWN_NEEDED_UNSET) |
| 46 | { |
| 47 | // This will be overridden by a DT_SONAME entry, hopefully. But if |
| 48 | // we never see a DT_SONAME entry, our rule is to use the dynamic |
| 49 | // object's filename. The only exception is when the dynamic object |
| 50 | // is part of an archive (so the filename is the archive's |
| 51 | // filename). In that case, we use just the dynobj's name-in-archive. |
| 52 | if (input_file == NULL) |
| 53 | this->soname_ = name; |
| 54 | else |
| 55 | { |
| 56 | this->soname_ = input_file->found_name(); |
| 57 | if (this->offset() != 0) |
| 58 | { |
| 59 | std::string::size_type open_paren = this->name().find('('); |
| 60 | std::string::size_type close_paren = this->name().find(')'); |
| 61 | if (open_paren != std::string::npos |
| 62 | && close_paren != std::string::npos) |
| 63 | { |
| 64 | // It's an archive, and name() is of the form 'foo.a(bar.so)'. |
| 65 | open_paren += 1; |
| 66 | this->soname_ = this->name().substr(open_paren, |
| 67 | close_paren - open_paren); |
| 68 | } |
| 69 | } |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | // Class Sized_dynobj. |
| 74 | |
| 75 | template<int size, bool big_endian> |
| 76 | Sized_dynobj<size, big_endian>::Sized_dynobj( |
| 77 | const std::string& name, |
| 78 | Input_file* input_file, |
| 79 | off_t offset, |
| 80 | const elfcpp::Ehdr<size, big_endian>& ehdr) |
| 81 | : Dynobj(name, input_file, offset), |
| 82 | elf_file_(this, ehdr), |
| 83 | dynsym_shndx_(-1U), |
| 84 | symbols_(NULL), |
| 85 | defined_count_(0) |
| 86 | { |
| 87 | } |
| 88 | |
| 89 | // Set up the object. |
| 90 | |
| 91 | template<int size, bool big_endian> |
| 92 | void |
| 93 | Sized_dynobj<size, big_endian>::setup() |
| 94 | { |
| 95 | const unsigned int shnum = this->elf_file_.shnum(); |
| 96 | this->set_shnum(shnum); |
| 97 | } |
| 98 | |
| 99 | // Find the SHT_DYNSYM section and the various version sections, and |
| 100 | // the dynamic section, given the section headers. |
| 101 | |
| 102 | template<int size, bool big_endian> |
| 103 | void |
| 104 | Sized_dynobj<size, big_endian>::find_dynsym_sections( |
| 105 | const unsigned char* pshdrs, |
| 106 | unsigned int* pversym_shndx, |
| 107 | unsigned int* pverdef_shndx, |
| 108 | unsigned int* pverneed_shndx, |
| 109 | unsigned int* pdynamic_shndx) |
| 110 | { |
| 111 | *pversym_shndx = -1U; |
| 112 | *pverdef_shndx = -1U; |
| 113 | *pverneed_shndx = -1U; |
| 114 | *pdynamic_shndx = -1U; |
| 115 | |
| 116 | unsigned int symtab_shndx = 0; |
| 117 | unsigned int xindex_shndx = 0; |
| 118 | unsigned int xindex_link = 0; |
| 119 | const unsigned int shnum = this->shnum(); |
| 120 | const unsigned char* p = pshdrs; |
| 121 | for (unsigned int i = 0; i < shnum; ++i, p += This::shdr_size) |
| 122 | { |
| 123 | typename This::Shdr shdr(p); |
| 124 | |
| 125 | unsigned int* pi; |
| 126 | switch (shdr.get_sh_type()) |
| 127 | { |
| 128 | case elfcpp::SHT_DYNSYM: |
| 129 | this->dynsym_shndx_ = i; |
| 130 | if (xindex_shndx > 0 && xindex_link == i) |
| 131 | { |
| 132 | Xindex* xindex = new Xindex(this->elf_file_.large_shndx_offset()); |
| 133 | xindex->read_symtab_xindex<size, big_endian>(this, xindex_shndx, |
| 134 | pshdrs); |
| 135 | this->set_xindex(xindex); |
| 136 | } |
| 137 | pi = NULL; |
| 138 | break; |
| 139 | case elfcpp::SHT_SYMTAB: |
| 140 | symtab_shndx = i; |
| 141 | pi = NULL; |
| 142 | break; |
| 143 | case elfcpp::SHT_GNU_versym: |
| 144 | pi = pversym_shndx; |
| 145 | break; |
| 146 | case elfcpp::SHT_GNU_verdef: |
| 147 | pi = pverdef_shndx; |
| 148 | break; |
| 149 | case elfcpp::SHT_GNU_verneed: |
| 150 | pi = pverneed_shndx; |
| 151 | break; |
| 152 | case elfcpp::SHT_DYNAMIC: |
| 153 | pi = pdynamic_shndx; |
| 154 | break; |
| 155 | case elfcpp::SHT_SYMTAB_SHNDX: |
| 156 | xindex_shndx = i; |
| 157 | xindex_link = this->adjust_shndx(shdr.get_sh_link()); |
| 158 | if (xindex_link == this->dynsym_shndx_) |
| 159 | { |
| 160 | Xindex* xindex = new Xindex(this->elf_file_.large_shndx_offset()); |
| 161 | xindex->read_symtab_xindex<size, big_endian>(this, xindex_shndx, |
| 162 | pshdrs); |
| 163 | this->set_xindex(xindex); |
| 164 | } |
| 165 | pi = NULL; |
| 166 | break; |
| 167 | default: |
| 168 | pi = NULL; |
| 169 | break; |
| 170 | } |
| 171 | |
| 172 | if (pi == NULL) |
| 173 | continue; |
| 174 | |
| 175 | if (*pi != -1U) |
| 176 | this->error(_("unexpected duplicate type %u section: %u, %u"), |
| 177 | shdr.get_sh_type(), *pi, i); |
| 178 | |
| 179 | *pi = i; |
| 180 | } |
| 181 | |
| 182 | // If there is no dynamic symbol table, use the normal symbol table. |
| 183 | // On some SVR4 systems, a shared library is stored in an archive. |
| 184 | // The version stored in the archive only has a normal symbol table. |
| 185 | // It has an SONAME entry which points to another copy in the file |
| 186 | // system which has a dynamic symbol table as usual. This is way of |
| 187 | // addressing the issues which glibc addresses using GROUP with |
| 188 | // libc_nonshared.a. |
| 189 | if (this->dynsym_shndx_ == -1U && symtab_shndx != 0) |
| 190 | { |
| 191 | this->dynsym_shndx_ = symtab_shndx; |
| 192 | if (xindex_shndx > 0 && xindex_link == symtab_shndx) |
| 193 | { |
| 194 | Xindex* xindex = new Xindex(this->elf_file_.large_shndx_offset()); |
| 195 | xindex->read_symtab_xindex<size, big_endian>(this, xindex_shndx, |
| 196 | pshdrs); |
| 197 | this->set_xindex(xindex); |
| 198 | } |
| 199 | } |
| 200 | } |
| 201 | |
| 202 | // Read the contents of section SHNDX. PSHDRS points to the section |
| 203 | // headers. TYPE is the expected section type. LINK is the expected |
| 204 | // section link. Store the data in *VIEW and *VIEW_SIZE. The |
| 205 | // section's sh_info field is stored in *VIEW_INFO. |
| 206 | |
| 207 | template<int size, bool big_endian> |
| 208 | void |
| 209 | Sized_dynobj<size, big_endian>::read_dynsym_section( |
| 210 | const unsigned char* pshdrs, |
| 211 | unsigned int shndx, |
| 212 | elfcpp::SHT type, |
| 213 | unsigned int link, |
| 214 | File_view** view, |
| 215 | section_size_type* view_size, |
| 216 | unsigned int* view_info) |
| 217 | { |
| 218 | if (shndx == -1U) |
| 219 | { |
| 220 | *view = NULL; |
| 221 | *view_size = 0; |
| 222 | *view_info = 0; |
| 223 | return; |
| 224 | } |
| 225 | |
| 226 | typename This::Shdr shdr(pshdrs + shndx * This::shdr_size); |
| 227 | |
| 228 | gold_assert(shdr.get_sh_type() == type); |
| 229 | |
| 230 | if (this->adjust_shndx(shdr.get_sh_link()) != link) |
| 231 | this->error(_("unexpected link in section %u header: %u != %u"), |
| 232 | shndx, this->adjust_shndx(shdr.get_sh_link()), link); |
| 233 | |
| 234 | *view = this->get_lasting_view(shdr.get_sh_offset(), shdr.get_sh_size(), |
| 235 | true, false); |
| 236 | *view_size = convert_to_section_size_type(shdr.get_sh_size()); |
| 237 | *view_info = shdr.get_sh_info(); |
| 238 | } |
| 239 | |
| 240 | // Read the dynamic tags. Set the soname field if this shared object |
| 241 | // has a DT_SONAME tag. Record the DT_NEEDED tags. PSHDRS points to |
| 242 | // the section headers. DYNAMIC_SHNDX is the section index of the |
| 243 | // SHT_DYNAMIC section. STRTAB_SHNDX, STRTAB, and STRTAB_SIZE are the |
| 244 | // section index and contents of a string table which may be the one |
| 245 | // associated with the SHT_DYNAMIC section. |
| 246 | |
| 247 | template<int size, bool big_endian> |
| 248 | void |
| 249 | Sized_dynobj<size, big_endian>::read_dynamic(const unsigned char* pshdrs, |
| 250 | unsigned int dynamic_shndx, |
| 251 | unsigned int strtab_shndx, |
| 252 | const unsigned char* strtabu, |
| 253 | off_t strtab_size) |
| 254 | { |
| 255 | typename This::Shdr dynamicshdr(pshdrs + dynamic_shndx * This::shdr_size); |
| 256 | gold_assert(dynamicshdr.get_sh_type() == elfcpp::SHT_DYNAMIC); |
| 257 | |
| 258 | const off_t dynamic_size = dynamicshdr.get_sh_size(); |
| 259 | const unsigned char* pdynamic = this->get_view(dynamicshdr.get_sh_offset(), |
| 260 | dynamic_size, true, false); |
| 261 | |
| 262 | const unsigned int link = this->adjust_shndx(dynamicshdr.get_sh_link()); |
| 263 | if (link != strtab_shndx) |
| 264 | { |
| 265 | if (link >= this->shnum()) |
| 266 | { |
| 267 | this->error(_("DYNAMIC section %u link out of range: %u"), |
| 268 | dynamic_shndx, link); |
| 269 | return; |
| 270 | } |
| 271 | |
| 272 | typename This::Shdr strtabshdr(pshdrs + link * This::shdr_size); |
| 273 | if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB) |
| 274 | { |
| 275 | this->error(_("DYNAMIC section %u link %u is not a strtab"), |
| 276 | dynamic_shndx, link); |
| 277 | return; |
| 278 | } |
| 279 | |
| 280 | strtab_size = strtabshdr.get_sh_size(); |
| 281 | strtabu = this->get_view(strtabshdr.get_sh_offset(), strtab_size, false, |
| 282 | false); |
| 283 | } |
| 284 | |
| 285 | const char* const strtab = reinterpret_cast<const char*>(strtabu); |
| 286 | |
| 287 | for (const unsigned char* p = pdynamic; |
| 288 | p < pdynamic + dynamic_size; |
| 289 | p += This::dyn_size) |
| 290 | { |
| 291 | typename This::Dyn dyn(p); |
| 292 | |
| 293 | switch (dyn.get_d_tag()) |
| 294 | { |
| 295 | case elfcpp::DT_NULL: |
| 296 | // We should always see DT_NULL at the end of the dynamic |
| 297 | // tags. |
| 298 | return; |
| 299 | |
| 300 | case elfcpp::DT_SONAME: |
| 301 | { |
| 302 | off_t val = dyn.get_d_val(); |
| 303 | if (val >= strtab_size) |
| 304 | this->error(_("DT_SONAME value out of range: %lld >= %lld"), |
| 305 | static_cast<long long>(val), |
| 306 | static_cast<long long>(strtab_size)); |
| 307 | else |
| 308 | this->set_soname_string(strtab + val); |
| 309 | } |
| 310 | break; |
| 311 | |
| 312 | case elfcpp::DT_NEEDED: |
| 313 | { |
| 314 | off_t val = dyn.get_d_val(); |
| 315 | if (val >= strtab_size) |
| 316 | this->error(_("DT_NEEDED value out of range: %lld >= %lld"), |
| 317 | static_cast<long long>(val), |
| 318 | static_cast<long long>(strtab_size)); |
| 319 | else |
| 320 | this->add_needed(strtab + val); |
| 321 | } |
| 322 | break; |
| 323 | |
| 324 | default: |
| 325 | break; |
| 326 | } |
| 327 | } |
| 328 | |
| 329 | this->error(_("missing DT_NULL in dynamic segment")); |
| 330 | } |
| 331 | |
| 332 | // Read the symbols and sections from a dynamic object. We read the |
| 333 | // dynamic symbols, not the normal symbols. |
| 334 | |
| 335 | template<int size, bool big_endian> |
| 336 | void |
| 337 | Sized_dynobj<size, big_endian>::do_read_symbols(Read_symbols_data* sd) |
| 338 | { |
| 339 | this->base_read_symbols(sd); |
| 340 | } |
| 341 | |
| 342 | // Read the symbols and sections from a dynamic object. We read the |
| 343 | // dynamic symbols, not the normal symbols. This is common code for |
| 344 | // all target-specific overrides of do_read_symbols(). |
| 345 | |
| 346 | template<int size, bool big_endian> |
| 347 | void |
| 348 | Sized_dynobj<size, big_endian>::base_read_symbols(Read_symbols_data* sd) |
| 349 | { |
| 350 | this->read_section_data(&this->elf_file_, sd); |
| 351 | |
| 352 | const unsigned char* const pshdrs = sd->section_headers->data(); |
| 353 | |
| 354 | unsigned int versym_shndx; |
| 355 | unsigned int verdef_shndx; |
| 356 | unsigned int verneed_shndx; |
| 357 | unsigned int dynamic_shndx; |
| 358 | this->find_dynsym_sections(pshdrs, &versym_shndx, &verdef_shndx, |
| 359 | &verneed_shndx, &dynamic_shndx); |
| 360 | |
| 361 | unsigned int strtab_shndx = -1U; |
| 362 | |
| 363 | sd->symbols = NULL; |
| 364 | sd->symbols_size = 0; |
| 365 | sd->external_symbols_offset = 0; |
| 366 | sd->symbol_names = NULL; |
| 367 | sd->symbol_names_size = 0; |
| 368 | sd->versym = NULL; |
| 369 | sd->versym_size = 0; |
| 370 | sd->verdef = NULL; |
| 371 | sd->verdef_size = 0; |
| 372 | sd->verdef_info = 0; |
| 373 | sd->verneed = NULL; |
| 374 | sd->verneed_size = 0; |
| 375 | sd->verneed_info = 0; |
| 376 | |
| 377 | const unsigned char* namesu = sd->section_names->data(); |
| 378 | const char* names = reinterpret_cast<const char*>(namesu); |
| 379 | if (memmem(names, sd->section_names_size, ".zdebug_", 8) != NULL) |
| 380 | { |
| 381 | Compressed_section_map* compressed_sections = |
| 382 | build_compressed_section_map<size, big_endian>( |
| 383 | pshdrs, this->shnum(), names, sd->section_names_size, this, true); |
| 384 | if (compressed_sections != NULL) |
| 385 | this->set_compressed_sections(compressed_sections); |
| 386 | } |
| 387 | |
| 388 | if (this->dynsym_shndx_ != -1U) |
| 389 | { |
| 390 | // Get the dynamic symbols. |
| 391 | typename This::Shdr dynsymshdr(pshdrs |
| 392 | + this->dynsym_shndx_ * This::shdr_size); |
| 393 | |
| 394 | sd->symbols = this->get_lasting_view(dynsymshdr.get_sh_offset(), |
| 395 | dynsymshdr.get_sh_size(), true, |
| 396 | false); |
| 397 | sd->symbols_size = |
| 398 | convert_to_section_size_type(dynsymshdr.get_sh_size()); |
| 399 | |
| 400 | // Get the symbol names. |
| 401 | strtab_shndx = this->adjust_shndx(dynsymshdr.get_sh_link()); |
| 402 | if (strtab_shndx >= this->shnum()) |
| 403 | { |
| 404 | this->error(_("invalid dynamic symbol table name index: %u"), |
| 405 | strtab_shndx); |
| 406 | return; |
| 407 | } |
| 408 | typename This::Shdr strtabshdr(pshdrs + strtab_shndx * This::shdr_size); |
| 409 | if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB) |
| 410 | { |
| 411 | this->error(_("dynamic symbol table name section " |
| 412 | "has wrong type: %u"), |
| 413 | static_cast<unsigned int>(strtabshdr.get_sh_type())); |
| 414 | return; |
| 415 | } |
| 416 | |
| 417 | sd->symbol_names = this->get_lasting_view(strtabshdr.get_sh_offset(), |
| 418 | strtabshdr.get_sh_size(), |
| 419 | false, false); |
| 420 | sd->symbol_names_size = |
| 421 | convert_to_section_size_type(strtabshdr.get_sh_size()); |
| 422 | |
| 423 | // Get the version information. |
| 424 | |
| 425 | unsigned int dummy; |
| 426 | this->read_dynsym_section(pshdrs, versym_shndx, elfcpp::SHT_GNU_versym, |
| 427 | this->dynsym_shndx_, |
| 428 | &sd->versym, &sd->versym_size, &dummy); |
| 429 | |
| 430 | // We require that the version definition and need section link |
| 431 | // to the same string table as the dynamic symbol table. This |
| 432 | // is not a technical requirement, but it always happens in |
| 433 | // practice. We could change this if necessary. |
| 434 | |
| 435 | this->read_dynsym_section(pshdrs, verdef_shndx, elfcpp::SHT_GNU_verdef, |
| 436 | strtab_shndx, &sd->verdef, &sd->verdef_size, |
| 437 | &sd->verdef_info); |
| 438 | |
| 439 | this->read_dynsym_section(pshdrs, verneed_shndx, elfcpp::SHT_GNU_verneed, |
| 440 | strtab_shndx, &sd->verneed, &sd->verneed_size, |
| 441 | &sd->verneed_info); |
| 442 | } |
| 443 | |
| 444 | // Read the SHT_DYNAMIC section to find whether this shared object |
| 445 | // has a DT_SONAME tag and to record any DT_NEEDED tags. This |
| 446 | // doesn't really have anything to do with reading the symbols, but |
| 447 | // this is a convenient place to do it. |
| 448 | if (dynamic_shndx != -1U) |
| 449 | this->read_dynamic(pshdrs, dynamic_shndx, strtab_shndx, |
| 450 | (sd->symbol_names == NULL |
| 451 | ? NULL |
| 452 | : sd->symbol_names->data()), |
| 453 | sd->symbol_names_size); |
| 454 | } |
| 455 | |
| 456 | // Return the Xindex structure to use for object with lots of |
| 457 | // sections. |
| 458 | |
| 459 | template<int size, bool big_endian> |
| 460 | Xindex* |
| 461 | Sized_dynobj<size, big_endian>::do_initialize_xindex() |
| 462 | { |
| 463 | gold_assert(this->dynsym_shndx_ != -1U); |
| 464 | Xindex* xindex = new Xindex(this->elf_file_.large_shndx_offset()); |
| 465 | xindex->initialize_symtab_xindex<size, big_endian>(this, this->dynsym_shndx_); |
| 466 | return xindex; |
| 467 | } |
| 468 | |
| 469 | // Lay out the input sections for a dynamic object. We don't want to |
| 470 | // include sections from a dynamic object, so all that we actually do |
| 471 | // here is check for .gnu.warning and .note.GNU-split-stack sections. |
| 472 | |
| 473 | template<int size, bool big_endian> |
| 474 | void |
| 475 | Sized_dynobj<size, big_endian>::do_layout(Symbol_table* symtab, |
| 476 | Layout*, |
| 477 | Read_symbols_data* sd) |
| 478 | { |
| 479 | const unsigned int shnum = this->shnum(); |
| 480 | if (shnum == 0) |
| 481 | return; |
| 482 | |
| 483 | // Get the section headers. |
| 484 | const unsigned char* pshdrs = sd->section_headers->data(); |
| 485 | |
| 486 | // Get the section names. |
| 487 | const unsigned char* pnamesu = sd->section_names->data(); |
| 488 | const char* pnames = reinterpret_cast<const char*>(pnamesu); |
| 489 | |
| 490 | // Skip the first, dummy, section. |
| 491 | pshdrs += This::shdr_size; |
| 492 | for (unsigned int i = 1; i < shnum; ++i, pshdrs += This::shdr_size) |
| 493 | { |
| 494 | typename This::Shdr shdr(pshdrs); |
| 495 | |
| 496 | if (shdr.get_sh_name() >= sd->section_names_size) |
| 497 | { |
| 498 | this->error(_("bad section name offset for section %u: %lu"), |
| 499 | i, static_cast<unsigned long>(shdr.get_sh_name())); |
| 500 | return; |
| 501 | } |
| 502 | |
| 503 | const char* name = pnames + shdr.get_sh_name(); |
| 504 | |
| 505 | this->handle_gnu_warning_section(name, i, symtab); |
| 506 | this->handle_split_stack_section(name); |
| 507 | } |
| 508 | |
| 509 | delete sd->section_headers; |
| 510 | sd->section_headers = NULL; |
| 511 | delete sd->section_names; |
| 512 | sd->section_names = NULL; |
| 513 | } |
| 514 | |
| 515 | // Add an entry to the vector mapping version numbers to version |
| 516 | // strings. |
| 517 | |
| 518 | template<int size, bool big_endian> |
| 519 | void |
| 520 | Sized_dynobj<size, big_endian>::set_version_map( |
| 521 | Version_map* version_map, |
| 522 | unsigned int ndx, |
| 523 | const char* name) const |
| 524 | { |
| 525 | if (ndx >= version_map->size()) |
| 526 | version_map->resize(ndx + 1); |
| 527 | if ((*version_map)[ndx] != NULL) |
| 528 | this->error(_("duplicate definition for version %u"), ndx); |
| 529 | (*version_map)[ndx] = name; |
| 530 | } |
| 531 | |
| 532 | // Add mappings for the version definitions to VERSION_MAP. |
| 533 | |
| 534 | template<int size, bool big_endian> |
| 535 | void |
| 536 | Sized_dynobj<size, big_endian>::make_verdef_map( |
| 537 | Read_symbols_data* sd, |
| 538 | Version_map* version_map) const |
| 539 | { |
| 540 | if (sd->verdef == NULL) |
| 541 | return; |
| 542 | |
| 543 | const char* names = reinterpret_cast<const char*>(sd->symbol_names->data()); |
| 544 | section_size_type names_size = sd->symbol_names_size; |
| 545 | |
| 546 | const unsigned char* pverdef = sd->verdef->data(); |
| 547 | section_size_type verdef_size = sd->verdef_size; |
| 548 | const unsigned int count = sd->verdef_info; |
| 549 | |
| 550 | const unsigned char* p = pverdef; |
| 551 | for (unsigned int i = 0; i < count; ++i) |
| 552 | { |
| 553 | elfcpp::Verdef<size, big_endian> verdef(p); |
| 554 | |
| 555 | if (verdef.get_vd_version() != elfcpp::VER_DEF_CURRENT) |
| 556 | { |
| 557 | this->error(_("unexpected verdef version %u"), |
| 558 | verdef.get_vd_version()); |
| 559 | return; |
| 560 | } |
| 561 | |
| 562 | const section_size_type vd_ndx = verdef.get_vd_ndx(); |
| 563 | |
| 564 | // The GNU linker clears the VERSYM_HIDDEN bit. I'm not |
| 565 | // sure why. |
| 566 | |
| 567 | // The first Verdaux holds the name of this version. Subsequent |
| 568 | // ones are versions that this one depends upon, which we don't |
| 569 | // care about here. |
| 570 | const section_size_type vd_cnt = verdef.get_vd_cnt(); |
| 571 | if (vd_cnt < 1) |
| 572 | { |
| 573 | this->error(_("verdef vd_cnt field too small: %u"), |
| 574 | static_cast<unsigned int>(vd_cnt)); |
| 575 | return; |
| 576 | } |
| 577 | |
| 578 | const section_size_type vd_aux = verdef.get_vd_aux(); |
| 579 | if ((p - pverdef) + vd_aux >= verdef_size) |
| 580 | { |
| 581 | this->error(_("verdef vd_aux field out of range: %u"), |
| 582 | static_cast<unsigned int>(vd_aux)); |
| 583 | return; |
| 584 | } |
| 585 | |
| 586 | const unsigned char* pvda = p + vd_aux; |
| 587 | elfcpp::Verdaux<size, big_endian> verdaux(pvda); |
| 588 | |
| 589 | const section_size_type vda_name = verdaux.get_vda_name(); |
| 590 | if (vda_name >= names_size) |
| 591 | { |
| 592 | this->error(_("verdaux vda_name field out of range: %u"), |
| 593 | static_cast<unsigned int>(vda_name)); |
| 594 | return; |
| 595 | } |
| 596 | |
| 597 | this->set_version_map(version_map, vd_ndx, names + vda_name); |
| 598 | |
| 599 | const section_size_type vd_next = verdef.get_vd_next(); |
| 600 | if ((p - pverdef) + vd_next >= verdef_size) |
| 601 | { |
| 602 | this->error(_("verdef vd_next field out of range: %u"), |
| 603 | static_cast<unsigned int>(vd_next)); |
| 604 | return; |
| 605 | } |
| 606 | |
| 607 | p += vd_next; |
| 608 | } |
| 609 | } |
| 610 | |
| 611 | // Add mappings for the required versions to VERSION_MAP. |
| 612 | |
| 613 | template<int size, bool big_endian> |
| 614 | void |
| 615 | Sized_dynobj<size, big_endian>::make_verneed_map( |
| 616 | Read_symbols_data* sd, |
| 617 | Version_map* version_map) const |
| 618 | { |
| 619 | if (sd->verneed == NULL) |
| 620 | return; |
| 621 | |
| 622 | const char* names = reinterpret_cast<const char*>(sd->symbol_names->data()); |
| 623 | section_size_type names_size = sd->symbol_names_size; |
| 624 | |
| 625 | const unsigned char* pverneed = sd->verneed->data(); |
| 626 | const section_size_type verneed_size = sd->verneed_size; |
| 627 | const unsigned int count = sd->verneed_info; |
| 628 | |
| 629 | const unsigned char* p = pverneed; |
| 630 | for (unsigned int i = 0; i < count; ++i) |
| 631 | { |
| 632 | elfcpp::Verneed<size, big_endian> verneed(p); |
| 633 | |
| 634 | if (verneed.get_vn_version() != elfcpp::VER_NEED_CURRENT) |
| 635 | { |
| 636 | this->error(_("unexpected verneed version %u"), |
| 637 | verneed.get_vn_version()); |
| 638 | return; |
| 639 | } |
| 640 | |
| 641 | const section_size_type vn_aux = verneed.get_vn_aux(); |
| 642 | |
| 643 | if ((p - pverneed) + vn_aux >= verneed_size) |
| 644 | { |
| 645 | this->error(_("verneed vn_aux field out of range: %u"), |
| 646 | static_cast<unsigned int>(vn_aux)); |
| 647 | return; |
| 648 | } |
| 649 | |
| 650 | const unsigned int vn_cnt = verneed.get_vn_cnt(); |
| 651 | const unsigned char* pvna = p + vn_aux; |
| 652 | for (unsigned int j = 0; j < vn_cnt; ++j) |
| 653 | { |
| 654 | elfcpp::Vernaux<size, big_endian> vernaux(pvna); |
| 655 | |
| 656 | const unsigned int vna_name = vernaux.get_vna_name(); |
| 657 | if (vna_name >= names_size) |
| 658 | { |
| 659 | this->error(_("vernaux vna_name field out of range: %u"), |
| 660 | static_cast<unsigned int>(vna_name)); |
| 661 | return; |
| 662 | } |
| 663 | |
| 664 | this->set_version_map(version_map, vernaux.get_vna_other(), |
| 665 | names + vna_name); |
| 666 | |
| 667 | const section_size_type vna_next = vernaux.get_vna_next(); |
| 668 | if ((pvna - pverneed) + vna_next >= verneed_size) |
| 669 | { |
| 670 | this->error(_("verneed vna_next field out of range: %u"), |
| 671 | static_cast<unsigned int>(vna_next)); |
| 672 | return; |
| 673 | } |
| 674 | |
| 675 | pvna += vna_next; |
| 676 | } |
| 677 | |
| 678 | const section_size_type vn_next = verneed.get_vn_next(); |
| 679 | if ((p - pverneed) + vn_next >= verneed_size) |
| 680 | { |
| 681 | this->error(_("verneed vn_next field out of range: %u"), |
| 682 | static_cast<unsigned int>(vn_next)); |
| 683 | return; |
| 684 | } |
| 685 | |
| 686 | p += vn_next; |
| 687 | } |
| 688 | } |
| 689 | |
| 690 | // Create a vector mapping version numbers to version strings. |
| 691 | |
| 692 | template<int size, bool big_endian> |
| 693 | void |
| 694 | Sized_dynobj<size, big_endian>::make_version_map( |
| 695 | Read_symbols_data* sd, |
| 696 | Version_map* version_map) const |
| 697 | { |
| 698 | if (sd->verdef == NULL && sd->verneed == NULL) |
| 699 | return; |
| 700 | |
| 701 | // A guess at the maximum version number we will see. If this is |
| 702 | // wrong we will be less efficient but still correct. |
| 703 | version_map->reserve(sd->verdef_info + sd->verneed_info * 10); |
| 704 | |
| 705 | this->make_verdef_map(sd, version_map); |
| 706 | this->make_verneed_map(sd, version_map); |
| 707 | } |
| 708 | |
| 709 | // Add the dynamic symbols to the symbol table. |
| 710 | |
| 711 | template<int size, bool big_endian> |
| 712 | void |
| 713 | Sized_dynobj<size, big_endian>::do_add_symbols(Symbol_table* symtab, |
| 714 | Read_symbols_data* sd, |
| 715 | Layout*) |
| 716 | { |
| 717 | if (sd->symbols == NULL) |
| 718 | { |
| 719 | gold_assert(sd->symbol_names == NULL); |
| 720 | gold_assert(sd->versym == NULL && sd->verdef == NULL |
| 721 | && sd->verneed == NULL); |
| 722 | return; |
| 723 | } |
| 724 | |
| 725 | const int sym_size = This::sym_size; |
| 726 | const size_t symcount = sd->symbols_size / sym_size; |
| 727 | gold_assert(sd->external_symbols_offset == 0); |
| 728 | if (symcount * sym_size != sd->symbols_size) |
| 729 | { |
| 730 | this->error(_("size of dynamic symbols is not multiple of symbol size")); |
| 731 | return; |
| 732 | } |
| 733 | |
| 734 | Version_map version_map; |
| 735 | this->make_version_map(sd, &version_map); |
| 736 | |
| 737 | // If printing symbol counts or a cross reference table or |
| 738 | // preparing for an incremental link, we want to track symbols. |
| 739 | if (parameters->options().user_set_print_symbol_counts() |
| 740 | || parameters->options().cref() |
| 741 | || parameters->incremental()) |
| 742 | { |
| 743 | this->symbols_ = new Symbols(); |
| 744 | this->symbols_->resize(symcount); |
| 745 | } |
| 746 | |
| 747 | const char* sym_names = |
| 748 | reinterpret_cast<const char*>(sd->symbol_names->data()); |
| 749 | symtab->add_from_dynobj(this, sd->symbols->data(), symcount, |
| 750 | sym_names, sd->symbol_names_size, |
| 751 | (sd->versym == NULL |
| 752 | ? NULL |
| 753 | : sd->versym->data()), |
| 754 | sd->versym_size, |
| 755 | &version_map, |
| 756 | this->symbols_, |
| 757 | &this->defined_count_); |
| 758 | |
| 759 | delete sd->symbols; |
| 760 | sd->symbols = NULL; |
| 761 | delete sd->symbol_names; |
| 762 | sd->symbol_names = NULL; |
| 763 | if (sd->versym != NULL) |
| 764 | { |
| 765 | delete sd->versym; |
| 766 | sd->versym = NULL; |
| 767 | } |
| 768 | if (sd->verdef != NULL) |
| 769 | { |
| 770 | delete sd->verdef; |
| 771 | sd->verdef = NULL; |
| 772 | } |
| 773 | if (sd->verneed != NULL) |
| 774 | { |
| 775 | delete sd->verneed; |
| 776 | sd->verneed = NULL; |
| 777 | } |
| 778 | |
| 779 | // This is normally the last time we will read any data from this |
| 780 | // file. |
| 781 | this->clear_view_cache_marks(); |
| 782 | } |
| 783 | |
| 784 | template<int size, bool big_endian> |
| 785 | Archive::Should_include |
| 786 | Sized_dynobj<size, big_endian>::do_should_include_member(Symbol_table*, |
| 787 | Layout*, |
| 788 | Read_symbols_data*, |
| 789 | std::string*) |
| 790 | { |
| 791 | return Archive::SHOULD_INCLUDE_YES; |
| 792 | } |
| 793 | |
| 794 | // Iterate over global symbols, calling a visitor class V for each. |
| 795 | |
| 796 | template<int size, bool big_endian> |
| 797 | void |
| 798 | Sized_dynobj<size, big_endian>::do_for_all_global_symbols( |
| 799 | Read_symbols_data* sd, |
| 800 | Library_base::Symbol_visitor_base* v) |
| 801 | { |
| 802 | const char* sym_names = |
| 803 | reinterpret_cast<const char*>(sd->symbol_names->data()); |
| 804 | const unsigned char* syms = |
| 805 | sd->symbols->data() + sd->external_symbols_offset; |
| 806 | const int sym_size = elfcpp::Elf_sizes<size>::sym_size; |
| 807 | size_t symcount = ((sd->symbols_size - sd->external_symbols_offset) |
| 808 | / sym_size); |
| 809 | const unsigned char* p = syms; |
| 810 | |
| 811 | for (size_t i = 0; i < symcount; ++i, p += sym_size) |
| 812 | { |
| 813 | elfcpp::Sym<size, big_endian> sym(p); |
| 814 | if (sym.get_st_shndx() != elfcpp::SHN_UNDEF |
| 815 | && sym.get_st_bind() != elfcpp::STB_LOCAL) |
| 816 | v->visit(sym_names + sym.get_st_name()); |
| 817 | } |
| 818 | } |
| 819 | |
| 820 | // Iterate over local symbols, calling a visitor class V for each GOT offset |
| 821 | // associated with a local symbol. |
| 822 | |
| 823 | template<int size, bool big_endian> |
| 824 | void |
| 825 | Sized_dynobj<size, big_endian>::do_for_all_local_got_entries( |
| 826 | Got_offset_list::Visitor*) const |
| 827 | { |
| 828 | } |
| 829 | |
| 830 | // Get symbol counts. |
| 831 | |
| 832 | template<int size, bool big_endian> |
| 833 | void |
| 834 | Sized_dynobj<size, big_endian>::do_get_global_symbol_counts( |
| 835 | const Symbol_table*, |
| 836 | size_t* defined, |
| 837 | size_t* used) const |
| 838 | { |
| 839 | *defined = this->defined_count_; |
| 840 | size_t count = 0; |
| 841 | for (typename Symbols::const_iterator p = this->symbols_->begin(); |
| 842 | p != this->symbols_->end(); |
| 843 | ++p) |
| 844 | if (*p != NULL |
| 845 | && (*p)->source() == Symbol::FROM_OBJECT |
| 846 | && (*p)->object() == this |
| 847 | && (*p)->is_defined() |
| 848 | && (*p)->has_dynsym_index()) |
| 849 | ++count; |
| 850 | *used = count; |
| 851 | } |
| 852 | |
| 853 | // Given a vector of hash codes, compute the number of hash buckets to |
| 854 | // use. |
| 855 | |
| 856 | unsigned int |
| 857 | Dynobj::compute_bucket_count(const std::vector<uint32_t>& hashcodes, |
| 858 | bool for_gnu_hash_table) |
| 859 | { |
| 860 | // FIXME: Implement optional hash table optimization. |
| 861 | |
| 862 | // Array used to determine the number of hash table buckets to use |
| 863 | // based on the number of symbols there are. If there are fewer |
| 864 | // than 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 |
| 865 | // buckets, fewer than 37 we use 17 buckets, and so forth. We never |
| 866 | // use more than 262147 buckets. This is straight from the old GNU |
| 867 | // linker. |
| 868 | static const unsigned int buckets[] = |
| 869 | { |
| 870 | 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209, |
| 871 | 16411, 32771, 65537, 131101, 262147 |
| 872 | }; |
| 873 | const int buckets_count = sizeof buckets / sizeof buckets[0]; |
| 874 | |
| 875 | unsigned int symcount = hashcodes.size(); |
| 876 | unsigned int ret = 1; |
| 877 | const double full_fraction |
| 878 | = 1.0 - parameters->options().hash_bucket_empty_fraction(); |
| 879 | for (int i = 0; i < buckets_count; ++i) |
| 880 | { |
| 881 | if (symcount < buckets[i] * full_fraction) |
| 882 | break; |
| 883 | ret = buckets[i]; |
| 884 | } |
| 885 | |
| 886 | if (for_gnu_hash_table && ret < 2) |
| 887 | ret = 2; |
| 888 | |
| 889 | return ret; |
| 890 | } |
| 891 | |
| 892 | // The standard ELF hash function. This hash function must not |
| 893 | // change, as the dynamic linker uses it also. |
| 894 | |
| 895 | uint32_t |
| 896 | Dynobj::elf_hash(const char* name) |
| 897 | { |
| 898 | const unsigned char* nameu = reinterpret_cast<const unsigned char*>(name); |
| 899 | uint32_t h = 0; |
| 900 | unsigned char c; |
| 901 | while ((c = *nameu++) != '\0') |
| 902 | { |
| 903 | h = (h << 4) + c; |
| 904 | uint32_t g = h & 0xf0000000; |
| 905 | if (g != 0) |
| 906 | { |
| 907 | h ^= g >> 24; |
| 908 | // The ELF ABI says h &= ~g, but using xor is equivalent in |
| 909 | // this case (since g was set from h) and may save one |
| 910 | // instruction. |
| 911 | h ^= g; |
| 912 | } |
| 913 | } |
| 914 | return h; |
| 915 | } |
| 916 | |
| 917 | // Create a standard ELF hash table, setting *PPHASH and *PHASHLEN. |
| 918 | // DYNSYMS is a vector with all the global dynamic symbols. |
| 919 | // LOCAL_DYNSYM_COUNT is the number of local symbols in the dynamic |
| 920 | // symbol table. |
| 921 | |
| 922 | void |
| 923 | Dynobj::create_elf_hash_table(const std::vector<Symbol*>& dynsyms, |
| 924 | unsigned int local_dynsym_count, |
| 925 | unsigned char** pphash, |
| 926 | unsigned int* phashlen) |
| 927 | { |
| 928 | unsigned int dynsym_count = dynsyms.size(); |
| 929 | |
| 930 | // Get the hash values for all the symbols. |
| 931 | std::vector<uint32_t> dynsym_hashvals(dynsym_count); |
| 932 | for (unsigned int i = 0; i < dynsym_count; ++i) |
| 933 | dynsym_hashvals[i] = Dynobj::elf_hash(dynsyms[i]->name()); |
| 934 | |
| 935 | const unsigned int bucketcount = |
| 936 | Dynobj::compute_bucket_count(dynsym_hashvals, false); |
| 937 | |
| 938 | std::vector<uint32_t> bucket(bucketcount); |
| 939 | std::vector<uint32_t> chain(local_dynsym_count + dynsym_count); |
| 940 | |
| 941 | for (unsigned int i = 0; i < dynsym_count; ++i) |
| 942 | { |
| 943 | unsigned int dynsym_index = dynsyms[i]->dynsym_index(); |
| 944 | unsigned int bucketpos = dynsym_hashvals[i] % bucketcount; |
| 945 | chain[dynsym_index] = bucket[bucketpos]; |
| 946 | bucket[bucketpos] = dynsym_index; |
| 947 | } |
| 948 | |
| 949 | int size = parameters->target().hash_entry_size(); |
| 950 | unsigned int hashlen = ((2 |
| 951 | + bucketcount |
| 952 | + local_dynsym_count |
| 953 | + dynsym_count) |
| 954 | * size / 8); |
| 955 | unsigned char* phash = new unsigned char[hashlen]; |
| 956 | |
| 957 | bool big_endian = parameters->target().is_big_endian(); |
| 958 | if (size == 32) |
| 959 | { |
| 960 | if (big_endian) |
| 961 | { |
| 962 | #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG) |
| 963 | Dynobj::sized_create_elf_hash_table<32, true>(bucket, chain, phash, |
| 964 | hashlen); |
| 965 | #else |
| 966 | gold_unreachable(); |
| 967 | #endif |
| 968 | } |
| 969 | else |
| 970 | { |
| 971 | #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE) |
| 972 | Dynobj::sized_create_elf_hash_table<32, false>(bucket, chain, phash, |
| 973 | hashlen); |
| 974 | #else |
| 975 | gold_unreachable(); |
| 976 | #endif |
| 977 | } |
| 978 | } |
| 979 | else if (size == 64) |
| 980 | { |
| 981 | if (big_endian) |
| 982 | { |
| 983 | #if defined(HAVE_TARGET_32_BIG) || defined(HAVE_TARGET_64_BIG) |
| 984 | Dynobj::sized_create_elf_hash_table<64, true>(bucket, chain, phash, |
| 985 | hashlen); |
| 986 | #else |
| 987 | gold_unreachable(); |
| 988 | #endif |
| 989 | } |
| 990 | else |
| 991 | { |
| 992 | #if defined(HAVE_TARGET_32_LITTLE) || defined(HAVE_TARGET_64_LITTLE) |
| 993 | Dynobj::sized_create_elf_hash_table<64, false>(bucket, chain, phash, |
| 994 | hashlen); |
| 995 | #else |
| 996 | gold_unreachable(); |
| 997 | #endif |
| 998 | } |
| 999 | } |
| 1000 | else |
| 1001 | gold_unreachable(); |
| 1002 | |
| 1003 | *pphash = phash; |
| 1004 | *phashlen = hashlen; |
| 1005 | } |
| 1006 | |
| 1007 | // Fill in an ELF hash table. |
| 1008 | |
| 1009 | template<int size, bool big_endian> |
| 1010 | void |
| 1011 | Dynobj::sized_create_elf_hash_table(const std::vector<uint32_t>& bucket, |
| 1012 | const std::vector<uint32_t>& chain, |
| 1013 | unsigned char* phash, |
| 1014 | unsigned int hashlen) |
| 1015 | { |
| 1016 | unsigned char* p = phash; |
| 1017 | |
| 1018 | const unsigned int bucketcount = bucket.size(); |
| 1019 | const unsigned int chaincount = chain.size(); |
| 1020 | |
| 1021 | elfcpp::Swap<size, big_endian>::writeval(p, bucketcount); |
| 1022 | p += size / 8; |
| 1023 | elfcpp::Swap<size, big_endian>::writeval(p, chaincount); |
| 1024 | p += size / 8; |
| 1025 | |
| 1026 | for (unsigned int i = 0; i < bucketcount; ++i) |
| 1027 | { |
| 1028 | elfcpp::Swap<size, big_endian>::writeval(p, bucket[i]); |
| 1029 | p += size / 8; |
| 1030 | } |
| 1031 | |
| 1032 | for (unsigned int i = 0; i < chaincount; ++i) |
| 1033 | { |
| 1034 | elfcpp::Swap<size, big_endian>::writeval(p, chain[i]); |
| 1035 | p += size / 8; |
| 1036 | } |
| 1037 | |
| 1038 | gold_assert(static_cast<unsigned int>(p - phash) == hashlen); |
| 1039 | } |
| 1040 | |
| 1041 | // The hash function used for the GNU hash table. This hash function |
| 1042 | // must not change, as the dynamic linker uses it also. |
| 1043 | |
| 1044 | uint32_t |
| 1045 | Dynobj::gnu_hash(const char* name) |
| 1046 | { |
| 1047 | const unsigned char* nameu = reinterpret_cast<const unsigned char*>(name); |
| 1048 | uint32_t h = 5381; |
| 1049 | unsigned char c; |
| 1050 | while ((c = *nameu++) != '\0') |
| 1051 | h = (h << 5) + h + c; |
| 1052 | return h; |
| 1053 | } |
| 1054 | |
| 1055 | // Create a GNU hash table, setting *PPHASH and *PHASHLEN. GNU hash |
| 1056 | // tables are an extension to ELF which are recognized by the GNU |
| 1057 | // dynamic linker. They are referenced using dynamic tag DT_GNU_HASH. |
| 1058 | // TARGET is the target. DYNSYMS is a vector with all the global |
| 1059 | // symbols which will be going into the dynamic symbol table. |
| 1060 | // LOCAL_DYNSYM_COUNT is the number of local symbols in the dynamic |
| 1061 | // symbol table. |
| 1062 | |
| 1063 | void |
| 1064 | Dynobj::create_gnu_hash_table(const std::vector<Symbol*>& dynsyms, |
| 1065 | unsigned int local_dynsym_count, |
| 1066 | unsigned char** pphash, |
| 1067 | unsigned int* phashlen) |
| 1068 | { |
| 1069 | const unsigned int count = dynsyms.size(); |
| 1070 | |
| 1071 | // Sort the dynamic symbols into two vectors. Symbols which we do |
| 1072 | // not want to put into the hash table we store into |
| 1073 | // UNHASHED_DYNSYMS. Symbols which we do want to store we put into |
| 1074 | // HASHED_DYNSYMS. DYNSYM_HASHVALS is parallel to HASHED_DYNSYMS, |
| 1075 | // and records the hash codes. |
| 1076 | |
| 1077 | std::vector<Symbol*> unhashed_dynsyms; |
| 1078 | unhashed_dynsyms.reserve(count); |
| 1079 | |
| 1080 | std::vector<Symbol*> hashed_dynsyms; |
| 1081 | hashed_dynsyms.reserve(count); |
| 1082 | |
| 1083 | std::vector<uint32_t> dynsym_hashvals; |
| 1084 | dynsym_hashvals.reserve(count); |
| 1085 | |
| 1086 | for (unsigned int i = 0; i < count; ++i) |
| 1087 | { |
| 1088 | Symbol* sym = dynsyms[i]; |
| 1089 | |
| 1090 | if (!sym->needs_dynsym_value() |
| 1091 | && (sym->is_undefined() |
| 1092 | || sym->is_from_dynobj() |
| 1093 | || sym->is_forced_local())) |
| 1094 | unhashed_dynsyms.push_back(sym); |
| 1095 | else |
| 1096 | { |
| 1097 | hashed_dynsyms.push_back(sym); |
| 1098 | dynsym_hashvals.push_back(Dynobj::gnu_hash(sym->name())); |
| 1099 | } |
| 1100 | } |
| 1101 | |
| 1102 | // Put the unhashed symbols at the start of the global portion of |
| 1103 | // the dynamic symbol table. |
| 1104 | const unsigned int unhashed_count = unhashed_dynsyms.size(); |
| 1105 | unsigned int unhashed_dynsym_index = local_dynsym_count; |
| 1106 | for (unsigned int i = 0; i < unhashed_count; ++i) |
| 1107 | { |
| 1108 | unhashed_dynsyms[i]->set_dynsym_index(unhashed_dynsym_index); |
| 1109 | ++unhashed_dynsym_index; |
| 1110 | } |
| 1111 | |
| 1112 | // For the actual data generation we call out to a templatized |
| 1113 | // function. |
| 1114 | int size = parameters->target().get_size(); |
| 1115 | bool big_endian = parameters->target().is_big_endian(); |
| 1116 | if (size == 32) |
| 1117 | { |
| 1118 | if (big_endian) |
| 1119 | { |
| 1120 | #ifdef HAVE_TARGET_32_BIG |
| 1121 | Dynobj::sized_create_gnu_hash_table<32, true>(hashed_dynsyms, |
| 1122 | dynsym_hashvals, |
| 1123 | unhashed_dynsym_index, |
| 1124 | pphash, |
| 1125 | phashlen); |
| 1126 | #else |
| 1127 | gold_unreachable(); |
| 1128 | #endif |
| 1129 | } |
| 1130 | else |
| 1131 | { |
| 1132 | #ifdef HAVE_TARGET_32_LITTLE |
| 1133 | Dynobj::sized_create_gnu_hash_table<32, false>(hashed_dynsyms, |
| 1134 | dynsym_hashvals, |
| 1135 | unhashed_dynsym_index, |
| 1136 | pphash, |
| 1137 | phashlen); |
| 1138 | #else |
| 1139 | gold_unreachable(); |
| 1140 | #endif |
| 1141 | } |
| 1142 | } |
| 1143 | else if (size == 64) |
| 1144 | { |
| 1145 | if (big_endian) |
| 1146 | { |
| 1147 | #ifdef HAVE_TARGET_64_BIG |
| 1148 | Dynobj::sized_create_gnu_hash_table<64, true>(hashed_dynsyms, |
| 1149 | dynsym_hashvals, |
| 1150 | unhashed_dynsym_index, |
| 1151 | pphash, |
| 1152 | phashlen); |
| 1153 | #else |
| 1154 | gold_unreachable(); |
| 1155 | #endif |
| 1156 | } |
| 1157 | else |
| 1158 | { |
| 1159 | #ifdef HAVE_TARGET_64_LITTLE |
| 1160 | Dynobj::sized_create_gnu_hash_table<64, false>(hashed_dynsyms, |
| 1161 | dynsym_hashvals, |
| 1162 | unhashed_dynsym_index, |
| 1163 | pphash, |
| 1164 | phashlen); |
| 1165 | #else |
| 1166 | gold_unreachable(); |
| 1167 | #endif |
| 1168 | } |
| 1169 | } |
| 1170 | else |
| 1171 | gold_unreachable(); |
| 1172 | } |
| 1173 | |
| 1174 | // Create the actual data for a GNU hash table. This is just a copy |
| 1175 | // of the code from the old GNU linker. |
| 1176 | |
| 1177 | template<int size, bool big_endian> |
| 1178 | void |
| 1179 | Dynobj::sized_create_gnu_hash_table( |
| 1180 | const std::vector<Symbol*>& hashed_dynsyms, |
| 1181 | const std::vector<uint32_t>& dynsym_hashvals, |
| 1182 | unsigned int unhashed_dynsym_count, |
| 1183 | unsigned char** pphash, |
| 1184 | unsigned int* phashlen) |
| 1185 | { |
| 1186 | if (hashed_dynsyms.empty()) |
| 1187 | { |
| 1188 | // Special case for the empty hash table. |
| 1189 | unsigned int hashlen = 5 * 4 + size / 8; |
| 1190 | unsigned char* phash = new unsigned char[hashlen]; |
| 1191 | // One empty bucket. |
| 1192 | elfcpp::Swap<32, big_endian>::writeval(phash, 1); |
| 1193 | // Symbol index above unhashed symbols. |
| 1194 | elfcpp::Swap<32, big_endian>::writeval(phash + 4, unhashed_dynsym_count); |
| 1195 | // One word for bitmask. |
| 1196 | elfcpp::Swap<32, big_endian>::writeval(phash + 8, 1); |
| 1197 | // Only bloom filter. |
| 1198 | elfcpp::Swap<32, big_endian>::writeval(phash + 12, 0); |
| 1199 | // No valid hashes. |
| 1200 | elfcpp::Swap<size, big_endian>::writeval(phash + 16, 0); |
| 1201 | // No hashes in only bucket. |
| 1202 | elfcpp::Swap<32, big_endian>::writeval(phash + 16 + size / 8, 0); |
| 1203 | |
| 1204 | *phashlen = hashlen; |
| 1205 | *pphash = phash; |
| 1206 | |
| 1207 | return; |
| 1208 | } |
| 1209 | |
| 1210 | const unsigned int bucketcount = |
| 1211 | Dynobj::compute_bucket_count(dynsym_hashvals, true); |
| 1212 | |
| 1213 | const unsigned int nsyms = hashed_dynsyms.size(); |
| 1214 | |
| 1215 | uint32_t maskbitslog2 = 1; |
| 1216 | uint32_t x = nsyms >> 1; |
| 1217 | while (x != 0) |
| 1218 | { |
| 1219 | ++maskbitslog2; |
| 1220 | x >>= 1; |
| 1221 | } |
| 1222 | if (maskbitslog2 < 3) |
| 1223 | maskbitslog2 = 5; |
| 1224 | else if (((1U << (maskbitslog2 - 2)) & nsyms) != 0) |
| 1225 | maskbitslog2 += 3; |
| 1226 | else |
| 1227 | maskbitslog2 += 2; |
| 1228 | |
| 1229 | uint32_t shift1; |
| 1230 | if (size == 32) |
| 1231 | shift1 = 5; |
| 1232 | else |
| 1233 | { |
| 1234 | if (maskbitslog2 == 5) |
| 1235 | maskbitslog2 = 6; |
| 1236 | shift1 = 6; |
| 1237 | } |
| 1238 | uint32_t mask = (1U << shift1) - 1U; |
| 1239 | uint32_t shift2 = maskbitslog2; |
| 1240 | uint32_t maskbits = 1U << maskbitslog2; |
| 1241 | uint32_t maskwords = 1U << (maskbitslog2 - shift1); |
| 1242 | |
| 1243 | typedef typename elfcpp::Elf_types<size>::Elf_WXword Word; |
| 1244 | std::vector<Word> bitmask(maskwords); |
| 1245 | std::vector<uint32_t> counts(bucketcount); |
| 1246 | std::vector<uint32_t> indx(bucketcount); |
| 1247 | uint32_t symindx = unhashed_dynsym_count; |
| 1248 | |
| 1249 | // Count the number of times each hash bucket is used. |
| 1250 | for (unsigned int i = 0; i < nsyms; ++i) |
| 1251 | ++counts[dynsym_hashvals[i] % bucketcount]; |
| 1252 | |
| 1253 | unsigned int cnt = symindx; |
| 1254 | for (unsigned int i = 0; i < bucketcount; ++i) |
| 1255 | { |
| 1256 | indx[i] = cnt; |
| 1257 | cnt += counts[i]; |
| 1258 | } |
| 1259 | |
| 1260 | unsigned int hashlen = (4 + bucketcount + nsyms) * 4; |
| 1261 | hashlen += maskbits / 8; |
| 1262 | unsigned char* phash = new unsigned char[hashlen]; |
| 1263 | |
| 1264 | elfcpp::Swap<32, big_endian>::writeval(phash, bucketcount); |
| 1265 | elfcpp::Swap<32, big_endian>::writeval(phash + 4, symindx); |
| 1266 | elfcpp::Swap<32, big_endian>::writeval(phash + 8, maskwords); |
| 1267 | elfcpp::Swap<32, big_endian>::writeval(phash + 12, shift2); |
| 1268 | |
| 1269 | unsigned char* p = phash + 16 + maskbits / 8; |
| 1270 | for (unsigned int i = 0; i < bucketcount; ++i) |
| 1271 | { |
| 1272 | if (counts[i] == 0) |
| 1273 | elfcpp::Swap<32, big_endian>::writeval(p, 0); |
| 1274 | else |
| 1275 | elfcpp::Swap<32, big_endian>::writeval(p, indx[i]); |
| 1276 | p += 4; |
| 1277 | } |
| 1278 | |
| 1279 | for (unsigned int i = 0; i < nsyms; ++i) |
| 1280 | { |
| 1281 | Symbol* sym = hashed_dynsyms[i]; |
| 1282 | uint32_t hashval = dynsym_hashvals[i]; |
| 1283 | |
| 1284 | unsigned int bucket = hashval % bucketcount; |
| 1285 | unsigned int val = ((hashval >> shift1) |
| 1286 | & ((maskbits >> shift1) - 1)); |
| 1287 | bitmask[val] |= (static_cast<Word>(1U)) << (hashval & mask); |
| 1288 | bitmask[val] |= (static_cast<Word>(1U)) << ((hashval >> shift2) & mask); |
| 1289 | val = hashval & ~ 1U; |
| 1290 | if (counts[bucket] == 1) |
| 1291 | { |
| 1292 | // Last element terminates the chain. |
| 1293 | val |= 1; |
| 1294 | } |
| 1295 | elfcpp::Swap<32, big_endian>::writeval(p + (indx[bucket] - symindx) * 4, |
| 1296 | val); |
| 1297 | --counts[bucket]; |
| 1298 | |
| 1299 | sym->set_dynsym_index(indx[bucket]); |
| 1300 | ++indx[bucket]; |
| 1301 | } |
| 1302 | |
| 1303 | p = phash + 16; |
| 1304 | for (unsigned int i = 0; i < maskwords; ++i) |
| 1305 | { |
| 1306 | elfcpp::Swap<size, big_endian>::writeval(p, bitmask[i]); |
| 1307 | p += size / 8; |
| 1308 | } |
| 1309 | |
| 1310 | *phashlen = hashlen; |
| 1311 | *pphash = phash; |
| 1312 | } |
| 1313 | |
| 1314 | // Verdef methods. |
| 1315 | |
| 1316 | // Write this definition to a buffer for the output section. |
| 1317 | |
| 1318 | template<int size, bool big_endian> |
| 1319 | unsigned char* |
| 1320 | Verdef::write(const Stringpool* dynpool, bool is_last, unsigned char* pb) const |
| 1321 | { |
| 1322 | const int verdef_size = elfcpp::Elf_sizes<size>::verdef_size; |
| 1323 | const int verdaux_size = elfcpp::Elf_sizes<size>::verdaux_size; |
| 1324 | |
| 1325 | elfcpp::Verdef_write<size, big_endian> vd(pb); |
| 1326 | vd.set_vd_version(elfcpp::VER_DEF_CURRENT); |
| 1327 | vd.set_vd_flags((this->is_base_ ? elfcpp::VER_FLG_BASE : 0) |
| 1328 | | (this->is_weak_ ? elfcpp::VER_FLG_WEAK : 0) |
| 1329 | | (this->is_info_ ? elfcpp::VER_FLG_INFO : 0)); |
| 1330 | vd.set_vd_ndx(this->index()); |
| 1331 | vd.set_vd_cnt(1 + this->deps_.size()); |
| 1332 | vd.set_vd_hash(Dynobj::elf_hash(this->name())); |
| 1333 | vd.set_vd_aux(verdef_size); |
| 1334 | vd.set_vd_next(is_last |
| 1335 | ? 0 |
| 1336 | : verdef_size + (1 + this->deps_.size()) * verdaux_size); |
| 1337 | pb += verdef_size; |
| 1338 | |
| 1339 | elfcpp::Verdaux_write<size, big_endian> vda(pb); |
| 1340 | vda.set_vda_name(dynpool->get_offset(this->name())); |
| 1341 | vda.set_vda_next(this->deps_.empty() ? 0 : verdaux_size); |
| 1342 | pb += verdaux_size; |
| 1343 | |
| 1344 | Deps::const_iterator p; |
| 1345 | unsigned int i; |
| 1346 | for (p = this->deps_.begin(), i = 0; |
| 1347 | p != this->deps_.end(); |
| 1348 | ++p, ++i) |
| 1349 | { |
| 1350 | elfcpp::Verdaux_write<size, big_endian> vda(pb); |
| 1351 | vda.set_vda_name(dynpool->get_offset(*p)); |
| 1352 | vda.set_vda_next(i + 1 >= this->deps_.size() ? 0 : verdaux_size); |
| 1353 | pb += verdaux_size; |
| 1354 | } |
| 1355 | |
| 1356 | return pb; |
| 1357 | } |
| 1358 | |
| 1359 | // Verneed methods. |
| 1360 | |
| 1361 | Verneed::~Verneed() |
| 1362 | { |
| 1363 | for (Need_versions::iterator p = this->need_versions_.begin(); |
| 1364 | p != this->need_versions_.end(); |
| 1365 | ++p) |
| 1366 | delete *p; |
| 1367 | } |
| 1368 | |
| 1369 | // Add a new version to this file reference. |
| 1370 | |
| 1371 | Verneed_version* |
| 1372 | Verneed::add_name(const char* name) |
| 1373 | { |
| 1374 | Verneed_version* vv = new Verneed_version(name); |
| 1375 | this->need_versions_.push_back(vv); |
| 1376 | return vv; |
| 1377 | } |
| 1378 | |
| 1379 | // Set the version indexes starting at INDEX. |
| 1380 | |
| 1381 | unsigned int |
| 1382 | Verneed::finalize(unsigned int index) |
| 1383 | { |
| 1384 | for (Need_versions::iterator p = this->need_versions_.begin(); |
| 1385 | p != this->need_versions_.end(); |
| 1386 | ++p) |
| 1387 | { |
| 1388 | (*p)->set_index(index); |
| 1389 | ++index; |
| 1390 | } |
| 1391 | return index; |
| 1392 | } |
| 1393 | |
| 1394 | // Write this list of referenced versions to a buffer for the output |
| 1395 | // section. |
| 1396 | |
| 1397 | template<int size, bool big_endian> |
| 1398 | unsigned char* |
| 1399 | Verneed::write(const Stringpool* dynpool, bool is_last, |
| 1400 | unsigned char* pb) const |
| 1401 | { |
| 1402 | const int verneed_size = elfcpp::Elf_sizes<size>::verneed_size; |
| 1403 | const int vernaux_size = elfcpp::Elf_sizes<size>::vernaux_size; |
| 1404 | |
| 1405 | elfcpp::Verneed_write<size, big_endian> vn(pb); |
| 1406 | vn.set_vn_version(elfcpp::VER_NEED_CURRENT); |
| 1407 | vn.set_vn_cnt(this->need_versions_.size()); |
| 1408 | vn.set_vn_file(dynpool->get_offset(this->filename())); |
| 1409 | vn.set_vn_aux(verneed_size); |
| 1410 | vn.set_vn_next(is_last |
| 1411 | ? 0 |
| 1412 | : verneed_size + this->need_versions_.size() * vernaux_size); |
| 1413 | pb += verneed_size; |
| 1414 | |
| 1415 | Need_versions::const_iterator p; |
| 1416 | unsigned int i; |
| 1417 | for (p = this->need_versions_.begin(), i = 0; |
| 1418 | p != this->need_versions_.end(); |
| 1419 | ++p, ++i) |
| 1420 | { |
| 1421 | elfcpp::Vernaux_write<size, big_endian> vna(pb); |
| 1422 | vna.set_vna_hash(Dynobj::elf_hash((*p)->version())); |
| 1423 | // FIXME: We need to sometimes set VER_FLG_WEAK here. |
| 1424 | vna.set_vna_flags(0); |
| 1425 | vna.set_vna_other((*p)->index()); |
| 1426 | vna.set_vna_name(dynpool->get_offset((*p)->version())); |
| 1427 | vna.set_vna_next(i + 1 >= this->need_versions_.size() |
| 1428 | ? 0 |
| 1429 | : vernaux_size); |
| 1430 | pb += vernaux_size; |
| 1431 | } |
| 1432 | |
| 1433 | return pb; |
| 1434 | } |
| 1435 | |
| 1436 | // Versions methods. |
| 1437 | |
| 1438 | Versions::Versions(const Version_script_info& version_script, |
| 1439 | Stringpool* dynpool) |
| 1440 | : defs_(), needs_(), version_table_(), |
| 1441 | is_finalized_(false), version_script_(version_script), |
| 1442 | needs_base_version_(true) |
| 1443 | { |
| 1444 | if (!this->version_script_.empty()) |
| 1445 | { |
| 1446 | // Parse the version script, and insert each declared version into |
| 1447 | // defs_ and version_table_. |
| 1448 | std::vector<std::string> versions = this->version_script_.get_versions(); |
| 1449 | |
| 1450 | if (this->needs_base_version_ && !versions.empty()) |
| 1451 | this->define_base_version(dynpool); |
| 1452 | |
| 1453 | for (size_t k = 0; k < versions.size(); ++k) |
| 1454 | { |
| 1455 | Stringpool::Key version_key; |
| 1456 | const char* version = dynpool->add(versions[k].c_str(), |
| 1457 | true, &version_key); |
| 1458 | Verdef* const vd = new Verdef( |
| 1459 | version, |
| 1460 | this->version_script_.get_dependencies(version), |
| 1461 | false, false, false, false); |
| 1462 | this->defs_.push_back(vd); |
| 1463 | Key key(version_key, 0); |
| 1464 | this->version_table_.insert(std::make_pair(key, vd)); |
| 1465 | } |
| 1466 | } |
| 1467 | } |
| 1468 | |
| 1469 | Versions::~Versions() |
| 1470 | { |
| 1471 | for (Defs::iterator p = this->defs_.begin(); |
| 1472 | p != this->defs_.end(); |
| 1473 | ++p) |
| 1474 | delete *p; |
| 1475 | |
| 1476 | for (Needs::iterator p = this->needs_.begin(); |
| 1477 | p != this->needs_.end(); |
| 1478 | ++p) |
| 1479 | delete *p; |
| 1480 | } |
| 1481 | |
| 1482 | // Define the base version of a shared library. The base version definition |
| 1483 | // must be the first entry in defs_. We insert it lazily so that defs_ is |
| 1484 | // empty if no symbol versioning is used. Then layout can just drop the |
| 1485 | // version sections. |
| 1486 | |
| 1487 | void |
| 1488 | Versions::define_base_version(Stringpool* dynpool) |
| 1489 | { |
| 1490 | // If we do any versioning at all, we always need a base version, so |
| 1491 | // define that first. Nothing explicitly declares itself as part of base, |
| 1492 | // so it doesn't need to be in version_table_. |
| 1493 | gold_assert(this->defs_.empty()); |
| 1494 | const char* name = parameters->options().soname(); |
| 1495 | if (name == NULL) |
| 1496 | name = parameters->options().output_file_name(); |
| 1497 | name = dynpool->add(name, false, NULL); |
| 1498 | Verdef* vdbase = new Verdef(name, std::vector<std::string>(), |
| 1499 | true, false, false, true); |
| 1500 | this->defs_.push_back(vdbase); |
| 1501 | this->needs_base_version_ = false; |
| 1502 | } |
| 1503 | |
| 1504 | // Return the dynamic object which a symbol refers to. |
| 1505 | |
| 1506 | Dynobj* |
| 1507 | Versions::get_dynobj_for_sym(const Symbol_table* symtab, |
| 1508 | const Symbol* sym) const |
| 1509 | { |
| 1510 | if (sym->is_copied_from_dynobj()) |
| 1511 | return symtab->get_copy_source(sym); |
| 1512 | else |
| 1513 | { |
| 1514 | Object* object = sym->object(); |
| 1515 | gold_assert(object->is_dynamic()); |
| 1516 | return static_cast<Dynobj*>(object); |
| 1517 | } |
| 1518 | } |
| 1519 | |
| 1520 | // Record version information for a symbol going into the dynamic |
| 1521 | // symbol table. |
| 1522 | |
| 1523 | void |
| 1524 | Versions::record_version(const Symbol_table* symtab, |
| 1525 | Stringpool* dynpool, const Symbol* sym) |
| 1526 | { |
| 1527 | gold_assert(!this->is_finalized_); |
| 1528 | gold_assert(sym->version() != NULL); |
| 1529 | |
| 1530 | // A symbol defined as "sym@" is bound to an unspecified base version. |
| 1531 | if (sym->version()[0] == '\0') |
| 1532 | return; |
| 1533 | |
| 1534 | Stringpool::Key version_key; |
| 1535 | const char* version = dynpool->add(sym->version(), false, &version_key); |
| 1536 | |
| 1537 | if (!sym->is_from_dynobj() && !sym->is_copied_from_dynobj()) |
| 1538 | { |
| 1539 | this->add_def(dynpool, sym, version, version_key); |
| 1540 | } |
| 1541 | else |
| 1542 | { |
| 1543 | // This is a version reference. |
| 1544 | Dynobj* dynobj = this->get_dynobj_for_sym(symtab, sym); |
| 1545 | this->add_need(dynpool, dynobj->soname(), version, version_key); |
| 1546 | } |
| 1547 | } |
| 1548 | |
| 1549 | // We've found a symbol SYM defined in version VERSION. |
| 1550 | |
| 1551 | void |
| 1552 | Versions::add_def(Stringpool* dynpool, const Symbol* sym, const char* version, |
| 1553 | Stringpool::Key version_key) |
| 1554 | { |
| 1555 | Key k(version_key, 0); |
| 1556 | Version_base* const vbnull = NULL; |
| 1557 | std::pair<Version_table::iterator, bool> ins = |
| 1558 | this->version_table_.insert(std::make_pair(k, vbnull)); |
| 1559 | |
| 1560 | if (!ins.second) |
| 1561 | { |
| 1562 | // We already have an entry for this version. |
| 1563 | Version_base* vb = ins.first->second; |
| 1564 | |
| 1565 | // We have now seen a symbol in this version, so it is not |
| 1566 | // weak. |
| 1567 | gold_assert(vb != NULL); |
| 1568 | vb->clear_weak(); |
| 1569 | } |
| 1570 | else |
| 1571 | { |
| 1572 | // If we are creating a shared object, it is an error to |
| 1573 | // find a definition of a symbol with a version which is not |
| 1574 | // in the version script. |
| 1575 | if (parameters->options().shared()) |
| 1576 | gold_error(_("symbol %s has undefined version %s"), |
| 1577 | sym->demangled_name().c_str(), version); |
| 1578 | |
| 1579 | // When creating a regular executable, automatically define |
| 1580 | // a new version. |
| 1581 | if (this->needs_base_version_) |
| 1582 | this->define_base_version(dynpool); |
| 1583 | Verdef* vd = new Verdef(version, std::vector<std::string>(), |
| 1584 | false, false, false, false); |
| 1585 | this->defs_.push_back(vd); |
| 1586 | ins.first->second = vd; |
| 1587 | } |
| 1588 | } |
| 1589 | |
| 1590 | // Add a reference to version NAME in file FILENAME. |
| 1591 | |
| 1592 | void |
| 1593 | Versions::add_need(Stringpool* dynpool, const char* filename, const char* name, |
| 1594 | Stringpool::Key name_key) |
| 1595 | { |
| 1596 | Stringpool::Key filename_key; |
| 1597 | filename = dynpool->add(filename, true, &filename_key); |
| 1598 | |
| 1599 | Key k(name_key, filename_key); |
| 1600 | Version_base* const vbnull = NULL; |
| 1601 | std::pair<Version_table::iterator, bool> ins = |
| 1602 | this->version_table_.insert(std::make_pair(k, vbnull)); |
| 1603 | |
| 1604 | if (!ins.second) |
| 1605 | { |
| 1606 | // We already have an entry for this filename/version. |
| 1607 | return; |
| 1608 | } |
| 1609 | |
| 1610 | // See whether we already have this filename. We don't expect many |
| 1611 | // version references, so we just do a linear search. This could be |
| 1612 | // replaced by a hash table. |
| 1613 | Verneed* vn = NULL; |
| 1614 | for (Needs::iterator p = this->needs_.begin(); |
| 1615 | p != this->needs_.end(); |
| 1616 | ++p) |
| 1617 | { |
| 1618 | if ((*p)->filename() == filename) |
| 1619 | { |
| 1620 | vn = *p; |
| 1621 | break; |
| 1622 | } |
| 1623 | } |
| 1624 | |
| 1625 | if (vn == NULL) |
| 1626 | { |
| 1627 | // Create base version definition lazily for shared library. |
| 1628 | if (parameters->options().shared() && this->needs_base_version_) |
| 1629 | this->define_base_version(dynpool); |
| 1630 | |
| 1631 | // We have a new filename. |
| 1632 | vn = new Verneed(filename); |
| 1633 | this->needs_.push_back(vn); |
| 1634 | } |
| 1635 | |
| 1636 | ins.first->second = vn->add_name(name); |
| 1637 | } |
| 1638 | |
| 1639 | // Set the version indexes. Create a new dynamic version symbol for |
| 1640 | // each new version definition. |
| 1641 | |
| 1642 | unsigned int |
| 1643 | Versions::finalize(Symbol_table* symtab, unsigned int dynsym_index, |
| 1644 | std::vector<Symbol*>* syms) |
| 1645 | { |
| 1646 | gold_assert(!this->is_finalized_); |
| 1647 | |
| 1648 | unsigned int vi = 1; |
| 1649 | |
| 1650 | for (Defs::iterator p = this->defs_.begin(); |
| 1651 | p != this->defs_.end(); |
| 1652 | ++p) |
| 1653 | { |
| 1654 | (*p)->set_index(vi); |
| 1655 | ++vi; |
| 1656 | |
| 1657 | // Create a version symbol if necessary. |
| 1658 | if (!(*p)->is_symbol_created()) |
| 1659 | { |
| 1660 | Symbol* vsym = symtab->define_as_constant((*p)->name(), |
| 1661 | (*p)->name(), |
| 1662 | Symbol_table::PREDEFINED, |
| 1663 | 0, 0, |
| 1664 | elfcpp::STT_OBJECT, |
| 1665 | elfcpp::STB_GLOBAL, |
| 1666 | elfcpp::STV_DEFAULT, 0, |
| 1667 | false, false); |
| 1668 | vsym->set_needs_dynsym_entry(); |
| 1669 | vsym->set_dynsym_index(dynsym_index); |
| 1670 | vsym->set_is_default(); |
| 1671 | ++dynsym_index; |
| 1672 | syms->push_back(vsym); |
| 1673 | // The name is already in the dynamic pool. |
| 1674 | } |
| 1675 | } |
| 1676 | |
| 1677 | // Index 1 is used for global symbols. |
| 1678 | if (vi == 1) |
| 1679 | { |
| 1680 | gold_assert(this->defs_.empty()); |
| 1681 | vi = 2; |
| 1682 | } |
| 1683 | |
| 1684 | for (Needs::iterator p = this->needs_.begin(); |
| 1685 | p != this->needs_.end(); |
| 1686 | ++p) |
| 1687 | vi = (*p)->finalize(vi); |
| 1688 | |
| 1689 | this->is_finalized_ = true; |
| 1690 | |
| 1691 | return dynsym_index; |
| 1692 | } |
| 1693 | |
| 1694 | // Return the version index to use for a symbol. This does two hash |
| 1695 | // table lookups: one in DYNPOOL and one in this->version_table_. |
| 1696 | // Another approach alternative would be store a pointer in SYM, which |
| 1697 | // would increase the size of the symbol table. Or perhaps we could |
| 1698 | // use a hash table from dynamic symbol pointer values to Version_base |
| 1699 | // pointers. |
| 1700 | |
| 1701 | unsigned int |
| 1702 | Versions::version_index(const Symbol_table* symtab, const Stringpool* dynpool, |
| 1703 | const Symbol* sym) const |
| 1704 | { |
| 1705 | Stringpool::Key version_key; |
| 1706 | const char* version = dynpool->find(sym->version(), &version_key); |
| 1707 | gold_assert(version != NULL); |
| 1708 | |
| 1709 | Key k; |
| 1710 | if (!sym->is_from_dynobj() && !sym->is_copied_from_dynobj()) |
| 1711 | { |
| 1712 | k = Key(version_key, 0); |
| 1713 | } |
| 1714 | else |
| 1715 | { |
| 1716 | Dynobj* dynobj = this->get_dynobj_for_sym(symtab, sym); |
| 1717 | |
| 1718 | Stringpool::Key filename_key; |
| 1719 | const char* filename = dynpool->find(dynobj->soname(), &filename_key); |
| 1720 | gold_assert(filename != NULL); |
| 1721 | |
| 1722 | k = Key(version_key, filename_key); |
| 1723 | } |
| 1724 | |
| 1725 | Version_table::const_iterator p = this->version_table_.find(k); |
| 1726 | gold_assert(p != this->version_table_.end()); |
| 1727 | |
| 1728 | return p->second->index(); |
| 1729 | } |
| 1730 | |
| 1731 | // Return an allocated buffer holding the contents of the symbol |
| 1732 | // version section. |
| 1733 | |
| 1734 | template<int size, bool big_endian> |
| 1735 | void |
| 1736 | Versions::symbol_section_contents(const Symbol_table* symtab, |
| 1737 | const Stringpool* dynpool, |
| 1738 | unsigned int local_symcount, |
| 1739 | const std::vector<Symbol*>& syms, |
| 1740 | unsigned char** pp, |
| 1741 | unsigned int* psize) const |
| 1742 | { |
| 1743 | gold_assert(this->is_finalized_); |
| 1744 | |
| 1745 | unsigned int sz = (local_symcount + syms.size()) * 2; |
| 1746 | unsigned char* pbuf = new unsigned char[sz]; |
| 1747 | |
| 1748 | for (unsigned int i = 0; i < local_symcount; ++i) |
| 1749 | elfcpp::Swap<16, big_endian>::writeval(pbuf + i * 2, |
| 1750 | elfcpp::VER_NDX_LOCAL); |
| 1751 | |
| 1752 | for (std::vector<Symbol*>::const_iterator p = syms.begin(); |
| 1753 | p != syms.end(); |
| 1754 | ++p) |
| 1755 | { |
| 1756 | unsigned int version_index; |
| 1757 | const char* version = (*p)->version(); |
| 1758 | if (version == NULL) |
| 1759 | { |
| 1760 | if ((*p)->is_defined() && !(*p)->is_from_dynobj()) |
| 1761 | version_index = elfcpp::VER_NDX_GLOBAL; |
| 1762 | else |
| 1763 | version_index = elfcpp::VER_NDX_LOCAL; |
| 1764 | } |
| 1765 | else if (version[0] == '\0') |
| 1766 | version_index = elfcpp::VER_NDX_GLOBAL; |
| 1767 | else |
| 1768 | version_index = this->version_index(symtab, dynpool, *p); |
| 1769 | // If the symbol was defined as foo@V1 instead of foo@@V1, add |
| 1770 | // the hidden bit. |
| 1771 | if ((*p)->version() != NULL |
| 1772 | && (*p)->is_defined() |
| 1773 | && !(*p)->is_default() |
| 1774 | && !(*p)->from_dyn()) |
| 1775 | version_index |= elfcpp::VERSYM_HIDDEN; |
| 1776 | elfcpp::Swap<16, big_endian>::writeval(pbuf + (*p)->dynsym_index() * 2, |
| 1777 | version_index); |
| 1778 | } |
| 1779 | |
| 1780 | *pp = pbuf; |
| 1781 | *psize = sz; |
| 1782 | } |
| 1783 | |
| 1784 | // Return an allocated buffer holding the contents of the version |
| 1785 | // definition section. |
| 1786 | |
| 1787 | template<int size, bool big_endian> |
| 1788 | void |
| 1789 | Versions::def_section_contents(const Stringpool* dynpool, |
| 1790 | unsigned char** pp, unsigned int* psize, |
| 1791 | unsigned int* pentries) const |
| 1792 | { |
| 1793 | gold_assert(this->is_finalized_); |
| 1794 | gold_assert(!this->defs_.empty()); |
| 1795 | |
| 1796 | const int verdef_size = elfcpp::Elf_sizes<size>::verdef_size; |
| 1797 | const int verdaux_size = elfcpp::Elf_sizes<size>::verdaux_size; |
| 1798 | |
| 1799 | unsigned int sz = 0; |
| 1800 | for (Defs::const_iterator p = this->defs_.begin(); |
| 1801 | p != this->defs_.end(); |
| 1802 | ++p) |
| 1803 | { |
| 1804 | sz += verdef_size + verdaux_size; |
| 1805 | sz += (*p)->count_dependencies() * verdaux_size; |
| 1806 | } |
| 1807 | |
| 1808 | unsigned char* pbuf = new unsigned char[sz]; |
| 1809 | |
| 1810 | unsigned char* pb = pbuf; |
| 1811 | Defs::const_iterator p; |
| 1812 | unsigned int i; |
| 1813 | for (p = this->defs_.begin(), i = 0; |
| 1814 | p != this->defs_.end(); |
| 1815 | ++p, ++i) |
| 1816 | pb = (*p)->write<size, big_endian>(dynpool, |
| 1817 | i + 1 >= this->defs_.size(), |
| 1818 | pb); |
| 1819 | |
| 1820 | gold_assert(static_cast<unsigned int>(pb - pbuf) == sz); |
| 1821 | |
| 1822 | *pp = pbuf; |
| 1823 | *psize = sz; |
| 1824 | *pentries = this->defs_.size(); |
| 1825 | } |
| 1826 | |
| 1827 | // Return an allocated buffer holding the contents of the version |
| 1828 | // reference section. |
| 1829 | |
| 1830 | template<int size, bool big_endian> |
| 1831 | void |
| 1832 | Versions::need_section_contents(const Stringpool* dynpool, |
| 1833 | unsigned char** pp, unsigned int* psize, |
| 1834 | unsigned int* pentries) const |
| 1835 | { |
| 1836 | gold_assert(this->is_finalized_); |
| 1837 | gold_assert(!this->needs_.empty()); |
| 1838 | |
| 1839 | const int verneed_size = elfcpp::Elf_sizes<size>::verneed_size; |
| 1840 | const int vernaux_size = elfcpp::Elf_sizes<size>::vernaux_size; |
| 1841 | |
| 1842 | unsigned int sz = 0; |
| 1843 | for (Needs::const_iterator p = this->needs_.begin(); |
| 1844 | p != this->needs_.end(); |
| 1845 | ++p) |
| 1846 | { |
| 1847 | sz += verneed_size; |
| 1848 | sz += (*p)->count_versions() * vernaux_size; |
| 1849 | } |
| 1850 | |
| 1851 | unsigned char* pbuf = new unsigned char[sz]; |
| 1852 | |
| 1853 | unsigned char* pb = pbuf; |
| 1854 | Needs::const_iterator p; |
| 1855 | unsigned int i; |
| 1856 | for (p = this->needs_.begin(), i = 0; |
| 1857 | p != this->needs_.end(); |
| 1858 | ++p, ++i) |
| 1859 | pb = (*p)->write<size, big_endian>(dynpool, |
| 1860 | i + 1 >= this->needs_.size(), |
| 1861 | pb); |
| 1862 | |
| 1863 | gold_assert(static_cast<unsigned int>(pb - pbuf) == sz); |
| 1864 | |
| 1865 | *pp = pbuf; |
| 1866 | *psize = sz; |
| 1867 | *pentries = this->needs_.size(); |
| 1868 | } |
| 1869 | |
| 1870 | // Instantiate the templates we need. We could use the configure |
| 1871 | // script to restrict this to only the ones for implemented targets. |
| 1872 | |
| 1873 | #ifdef HAVE_TARGET_32_LITTLE |
| 1874 | template |
| 1875 | class Sized_dynobj<32, false>; |
| 1876 | #endif |
| 1877 | |
| 1878 | #ifdef HAVE_TARGET_32_BIG |
| 1879 | template |
| 1880 | class Sized_dynobj<32, true>; |
| 1881 | #endif |
| 1882 | |
| 1883 | #ifdef HAVE_TARGET_64_LITTLE |
| 1884 | template |
| 1885 | class Sized_dynobj<64, false>; |
| 1886 | #endif |
| 1887 | |
| 1888 | #ifdef HAVE_TARGET_64_BIG |
| 1889 | template |
| 1890 | class Sized_dynobj<64, true>; |
| 1891 | #endif |
| 1892 | |
| 1893 | #ifdef HAVE_TARGET_32_LITTLE |
| 1894 | template |
| 1895 | void |
| 1896 | Versions::symbol_section_contents<32, false>( |
| 1897 | const Symbol_table*, |
| 1898 | const Stringpool*, |
| 1899 | unsigned int, |
| 1900 | const std::vector<Symbol*>&, |
| 1901 | unsigned char**, |
| 1902 | unsigned int*) const; |
| 1903 | #endif |
| 1904 | |
| 1905 | #ifdef HAVE_TARGET_32_BIG |
| 1906 | template |
| 1907 | void |
| 1908 | Versions::symbol_section_contents<32, true>( |
| 1909 | const Symbol_table*, |
| 1910 | const Stringpool*, |
| 1911 | unsigned int, |
| 1912 | const std::vector<Symbol*>&, |
| 1913 | unsigned char**, |
| 1914 | unsigned int*) const; |
| 1915 | #endif |
| 1916 | |
| 1917 | #ifdef HAVE_TARGET_64_LITTLE |
| 1918 | template |
| 1919 | void |
| 1920 | Versions::symbol_section_contents<64, false>( |
| 1921 | const Symbol_table*, |
| 1922 | const Stringpool*, |
| 1923 | unsigned int, |
| 1924 | const std::vector<Symbol*>&, |
| 1925 | unsigned char**, |
| 1926 | unsigned int*) const; |
| 1927 | #endif |
| 1928 | |
| 1929 | #ifdef HAVE_TARGET_64_BIG |
| 1930 | template |
| 1931 | void |
| 1932 | Versions::symbol_section_contents<64, true>( |
| 1933 | const Symbol_table*, |
| 1934 | const Stringpool*, |
| 1935 | unsigned int, |
| 1936 | const std::vector<Symbol*>&, |
| 1937 | unsigned char**, |
| 1938 | unsigned int*) const; |
| 1939 | #endif |
| 1940 | |
| 1941 | #ifdef HAVE_TARGET_32_LITTLE |
| 1942 | template |
| 1943 | void |
| 1944 | Versions::def_section_contents<32, false>( |
| 1945 | const Stringpool*, |
| 1946 | unsigned char**, |
| 1947 | unsigned int*, |
| 1948 | unsigned int*) const; |
| 1949 | #endif |
| 1950 | |
| 1951 | #ifdef HAVE_TARGET_32_BIG |
| 1952 | template |
| 1953 | void |
| 1954 | Versions::def_section_contents<32, true>( |
| 1955 | const Stringpool*, |
| 1956 | unsigned char**, |
| 1957 | unsigned int*, |
| 1958 | unsigned int*) const; |
| 1959 | #endif |
| 1960 | |
| 1961 | #ifdef HAVE_TARGET_64_LITTLE |
| 1962 | template |
| 1963 | void |
| 1964 | Versions::def_section_contents<64, false>( |
| 1965 | const Stringpool*, |
| 1966 | unsigned char**, |
| 1967 | unsigned int*, |
| 1968 | unsigned int*) const; |
| 1969 | #endif |
| 1970 | |
| 1971 | #ifdef HAVE_TARGET_64_BIG |
| 1972 | template |
| 1973 | void |
| 1974 | Versions::def_section_contents<64, true>( |
| 1975 | const Stringpool*, |
| 1976 | unsigned char**, |
| 1977 | unsigned int*, |
| 1978 | unsigned int*) const; |
| 1979 | #endif |
| 1980 | |
| 1981 | #ifdef HAVE_TARGET_32_LITTLE |
| 1982 | template |
| 1983 | void |
| 1984 | Versions::need_section_contents<32, false>( |
| 1985 | const Stringpool*, |
| 1986 | unsigned char**, |
| 1987 | unsigned int*, |
| 1988 | unsigned int*) const; |
| 1989 | #endif |
| 1990 | |
| 1991 | #ifdef HAVE_TARGET_32_BIG |
| 1992 | template |
| 1993 | void |
| 1994 | Versions::need_section_contents<32, true>( |
| 1995 | const Stringpool*, |
| 1996 | unsigned char**, |
| 1997 | unsigned int*, |
| 1998 | unsigned int*) const; |
| 1999 | #endif |
| 2000 | |
| 2001 | #ifdef HAVE_TARGET_64_LITTLE |
| 2002 | template |
| 2003 | void |
| 2004 | Versions::need_section_contents<64, false>( |
| 2005 | const Stringpool*, |
| 2006 | unsigned char**, |
| 2007 | unsigned int*, |
| 2008 | unsigned int*) const; |
| 2009 | #endif |
| 2010 | |
| 2011 | #ifdef HAVE_TARGET_64_BIG |
| 2012 | template |
| 2013 | void |
| 2014 | Versions::need_section_contents<64, true>( |
| 2015 | const Stringpool*, |
| 2016 | unsigned char**, |
| 2017 | unsigned int*, |
| 2018 | unsigned int*) const; |
| 2019 | #endif |
| 2020 | |
| 2021 | } // End namespace gold. |