| 1 | // script-sections.cc -- linker script SECTIONS for gold |
| 2 | |
| 3 | // Copyright 2008 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 <cstring> |
| 26 | #include <algorithm> |
| 27 | #include <list> |
| 28 | #include <map> |
| 29 | #include <string> |
| 30 | #include <vector> |
| 31 | #include <fnmatch.h> |
| 32 | |
| 33 | #include "parameters.h" |
| 34 | #include "object.h" |
| 35 | #include "layout.h" |
| 36 | #include "output.h" |
| 37 | #include "script-c.h" |
| 38 | #include "script.h" |
| 39 | #include "script-sections.h" |
| 40 | |
| 41 | // Support for the SECTIONS clause in linker scripts. |
| 42 | |
| 43 | namespace gold |
| 44 | { |
| 45 | |
| 46 | // An element in a SECTIONS clause. |
| 47 | |
| 48 | class Sections_element |
| 49 | { |
| 50 | public: |
| 51 | Sections_element() |
| 52 | { } |
| 53 | |
| 54 | virtual ~Sections_element() |
| 55 | { } |
| 56 | |
| 57 | // Record that an output section is relro. |
| 58 | virtual void |
| 59 | set_is_relro() |
| 60 | { } |
| 61 | |
| 62 | // Create any required output sections. The only real |
| 63 | // implementation is in Output_section_definition. |
| 64 | virtual void |
| 65 | create_sections(Layout*) |
| 66 | { } |
| 67 | |
| 68 | // Add any symbol being defined to the symbol table. |
| 69 | virtual void |
| 70 | add_symbols_to_table(Symbol_table*) |
| 71 | { } |
| 72 | |
| 73 | // Finalize symbols and check assertions. |
| 74 | virtual void |
| 75 | finalize_symbols(Symbol_table*, const Layout*, uint64_t*) |
| 76 | { } |
| 77 | |
| 78 | // Return the output section name to use for an input file name and |
| 79 | // section name. This only real implementation is in |
| 80 | // Output_section_definition. |
| 81 | virtual const char* |
| 82 | output_section_name(const char*, const char*, Output_section***) |
| 83 | { return NULL; } |
| 84 | |
| 85 | // Return whether to place an orphan output section after this |
| 86 | // element. |
| 87 | virtual bool |
| 88 | place_orphan_here(const Output_section *, bool*, bool*) const |
| 89 | { return false; } |
| 90 | |
| 91 | // Set section addresses. This includes applying assignments if the |
| 92 | // the expression is an absolute value. |
| 93 | virtual void |
| 94 | set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*) |
| 95 | { } |
| 96 | |
| 97 | // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| 98 | // this section is constrained, and the input sections do not match, |
| 99 | // return the constraint, and set *POSD. |
| 100 | virtual Section_constraint |
| 101 | check_constraint(Output_section_definition**) |
| 102 | { return CONSTRAINT_NONE; } |
| 103 | |
| 104 | // See if this is the alternate output section for a constrained |
| 105 | // output section. If it is, transfer the Output_section and return |
| 106 | // true. Otherwise return false. |
| 107 | virtual bool |
| 108 | alternate_constraint(Output_section_definition*, Section_constraint) |
| 109 | { return false; } |
| 110 | |
| 111 | // Get the list of segments to use for an allocated section when |
| 112 | // using a PHDRS clause. If this is an allocated section, return |
| 113 | // the Output_section, and set *PHDRS_LIST (the first parameter) to |
| 114 | // the list of PHDRS to which it should be attached. If the PHDRS |
| 115 | // were not specified, don't change *PHDRS_LIST. When not returning |
| 116 | // NULL, set *ORPHAN (the second parameter) according to whether |
| 117 | // this is an orphan section--one that is not mentioned in the |
| 118 | // linker script. |
| 119 | virtual Output_section* |
| 120 | allocate_to_segment(String_list**, bool*) |
| 121 | { return NULL; } |
| 122 | |
| 123 | // Look for an output section by name and return the address, the |
| 124 | // load address, the alignment, and the size. This is used when an |
| 125 | // expression refers to an output section which was not actually |
| 126 | // created. This returns true if the section was found, false |
| 127 | // otherwise. The only real definition is for |
| 128 | // Output_section_definition. |
| 129 | virtual bool |
| 130 | get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*, |
| 131 | uint64_t*) const |
| 132 | { return false; } |
| 133 | |
| 134 | // Return the associated Output_section if there is one. |
| 135 | virtual Output_section* |
| 136 | get_output_section() const |
| 137 | { return NULL; } |
| 138 | |
| 139 | // Print the element for debugging purposes. |
| 140 | virtual void |
| 141 | print(FILE* f) const = 0; |
| 142 | }; |
| 143 | |
| 144 | // An assignment in a SECTIONS clause outside of an output section. |
| 145 | |
| 146 | class Sections_element_assignment : public Sections_element |
| 147 | { |
| 148 | public: |
| 149 | Sections_element_assignment(const char* name, size_t namelen, |
| 150 | Expression* val, bool provide, bool hidden) |
| 151 | : assignment_(name, namelen, val, provide, hidden) |
| 152 | { } |
| 153 | |
| 154 | // Add the symbol to the symbol table. |
| 155 | void |
| 156 | add_symbols_to_table(Symbol_table* symtab) |
| 157 | { this->assignment_.add_to_table(symtab); } |
| 158 | |
| 159 | // Finalize the symbol. |
| 160 | void |
| 161 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 162 | uint64_t* dot_value) |
| 163 | { |
| 164 | this->assignment_.finalize_with_dot(symtab, layout, *dot_value, NULL); |
| 165 | } |
| 166 | |
| 167 | // Set the section address. There is no section here, but if the |
| 168 | // value is absolute, we set the symbol. This permits us to use |
| 169 | // absolute symbols when setting dot. |
| 170 | void |
| 171 | set_section_addresses(Symbol_table* symtab, Layout* layout, |
| 172 | uint64_t* dot_value, uint64_t*) |
| 173 | { |
| 174 | this->assignment_.set_if_absolute(symtab, layout, true, *dot_value); |
| 175 | } |
| 176 | |
| 177 | // Print for debugging. |
| 178 | void |
| 179 | print(FILE* f) const |
| 180 | { |
| 181 | fprintf(f, " "); |
| 182 | this->assignment_.print(f); |
| 183 | } |
| 184 | |
| 185 | private: |
| 186 | Symbol_assignment assignment_; |
| 187 | }; |
| 188 | |
| 189 | // An assignment to the dot symbol in a SECTIONS clause outside of an |
| 190 | // output section. |
| 191 | |
| 192 | class Sections_element_dot_assignment : public Sections_element |
| 193 | { |
| 194 | public: |
| 195 | Sections_element_dot_assignment(Expression* val) |
| 196 | : val_(val) |
| 197 | { } |
| 198 | |
| 199 | // Finalize the symbol. |
| 200 | void |
| 201 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 202 | uint64_t* dot_value) |
| 203 | { |
| 204 | // We ignore the section of the result because outside of an |
| 205 | // output section definition the dot symbol is always considered |
| 206 | // to be absolute. |
| 207 | Output_section* dummy; |
| 208 | *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value, |
| 209 | NULL, &dummy); |
| 210 | } |
| 211 | |
| 212 | // Update the dot symbol while setting section addresses. |
| 213 | void |
| 214 | set_section_addresses(Symbol_table* symtab, Layout* layout, |
| 215 | uint64_t* dot_value, uint64_t* load_address) |
| 216 | { |
| 217 | Output_section* dummy; |
| 218 | *dot_value = this->val_->eval_with_dot(symtab, layout, false, *dot_value, |
| 219 | NULL, &dummy); |
| 220 | *load_address = *dot_value; |
| 221 | } |
| 222 | |
| 223 | // Print for debugging. |
| 224 | void |
| 225 | print(FILE* f) const |
| 226 | { |
| 227 | fprintf(f, " . = "); |
| 228 | this->val_->print(f); |
| 229 | fprintf(f, "\n"); |
| 230 | } |
| 231 | |
| 232 | private: |
| 233 | Expression* val_; |
| 234 | }; |
| 235 | |
| 236 | // An assertion in a SECTIONS clause outside of an output section. |
| 237 | |
| 238 | class Sections_element_assertion : public Sections_element |
| 239 | { |
| 240 | public: |
| 241 | Sections_element_assertion(Expression* check, const char* message, |
| 242 | size_t messagelen) |
| 243 | : assertion_(check, message, messagelen) |
| 244 | { } |
| 245 | |
| 246 | // Check the assertion. |
| 247 | void |
| 248 | finalize_symbols(Symbol_table* symtab, const Layout* layout, uint64_t*) |
| 249 | { this->assertion_.check(symtab, layout); } |
| 250 | |
| 251 | // Print for debugging. |
| 252 | void |
| 253 | print(FILE* f) const |
| 254 | { |
| 255 | fprintf(f, " "); |
| 256 | this->assertion_.print(f); |
| 257 | } |
| 258 | |
| 259 | private: |
| 260 | Script_assertion assertion_; |
| 261 | }; |
| 262 | |
| 263 | // An element in an output section in a SECTIONS clause. |
| 264 | |
| 265 | class Output_section_element |
| 266 | { |
| 267 | public: |
| 268 | // A list of input sections. |
| 269 | typedef std::list<std::pair<Relobj*, unsigned int> > Input_section_list; |
| 270 | |
| 271 | Output_section_element() |
| 272 | { } |
| 273 | |
| 274 | virtual ~Output_section_element() |
| 275 | { } |
| 276 | |
| 277 | // Return whether this element requires an output section to exist. |
| 278 | virtual bool |
| 279 | needs_output_section() const |
| 280 | { return false; } |
| 281 | |
| 282 | // Add any symbol being defined to the symbol table. |
| 283 | virtual void |
| 284 | add_symbols_to_table(Symbol_table*) |
| 285 | { } |
| 286 | |
| 287 | // Finalize symbols and check assertions. |
| 288 | virtual void |
| 289 | finalize_symbols(Symbol_table*, const Layout*, uint64_t*, Output_section**) |
| 290 | { } |
| 291 | |
| 292 | // Return whether this element matches FILE_NAME and SECTION_NAME. |
| 293 | // The only real implementation is in Output_section_element_input. |
| 294 | virtual bool |
| 295 | match_name(const char*, const char*) const |
| 296 | { return false; } |
| 297 | |
| 298 | // Set section addresses. This includes applying assignments if the |
| 299 | // the expression is an absolute value. |
| 300 | virtual void |
| 301 | set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t, |
| 302 | uint64_t*, Output_section**, std::string*, |
| 303 | Input_section_list*) |
| 304 | { } |
| 305 | |
| 306 | // Print the element for debugging purposes. |
| 307 | virtual void |
| 308 | print(FILE* f) const = 0; |
| 309 | |
| 310 | protected: |
| 311 | // Return a fill string that is LENGTH bytes long, filling it with |
| 312 | // FILL. |
| 313 | std::string |
| 314 | get_fill_string(const std::string* fill, section_size_type length) const; |
| 315 | }; |
| 316 | |
| 317 | std::string |
| 318 | Output_section_element::get_fill_string(const std::string* fill, |
| 319 | section_size_type length) const |
| 320 | { |
| 321 | std::string this_fill; |
| 322 | this_fill.reserve(length); |
| 323 | while (this_fill.length() + fill->length() <= length) |
| 324 | this_fill += *fill; |
| 325 | if (this_fill.length() < length) |
| 326 | this_fill.append(*fill, 0, length - this_fill.length()); |
| 327 | return this_fill; |
| 328 | } |
| 329 | |
| 330 | // A symbol assignment in an output section. |
| 331 | |
| 332 | class Output_section_element_assignment : public Output_section_element |
| 333 | { |
| 334 | public: |
| 335 | Output_section_element_assignment(const char* name, size_t namelen, |
| 336 | Expression* val, bool provide, |
| 337 | bool hidden) |
| 338 | : assignment_(name, namelen, val, provide, hidden) |
| 339 | { } |
| 340 | |
| 341 | // Add the symbol to the symbol table. |
| 342 | void |
| 343 | add_symbols_to_table(Symbol_table* symtab) |
| 344 | { this->assignment_.add_to_table(symtab); } |
| 345 | |
| 346 | // Finalize the symbol. |
| 347 | void |
| 348 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 349 | uint64_t* dot_value, Output_section** dot_section) |
| 350 | { |
| 351 | this->assignment_.finalize_with_dot(symtab, layout, *dot_value, |
| 352 | *dot_section); |
| 353 | } |
| 354 | |
| 355 | // Set the section address. There is no section here, but if the |
| 356 | // value is absolute, we set the symbol. This permits us to use |
| 357 | // absolute symbols when setting dot. |
| 358 | void |
| 359 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 360 | uint64_t, uint64_t* dot_value, Output_section**, |
| 361 | std::string*, Input_section_list*) |
| 362 | { |
| 363 | this->assignment_.set_if_absolute(symtab, layout, true, *dot_value); |
| 364 | } |
| 365 | |
| 366 | // Print for debugging. |
| 367 | void |
| 368 | print(FILE* f) const |
| 369 | { |
| 370 | fprintf(f, " "); |
| 371 | this->assignment_.print(f); |
| 372 | } |
| 373 | |
| 374 | private: |
| 375 | Symbol_assignment assignment_; |
| 376 | }; |
| 377 | |
| 378 | // An assignment to the dot symbol in an output section. |
| 379 | |
| 380 | class Output_section_element_dot_assignment : public Output_section_element |
| 381 | { |
| 382 | public: |
| 383 | Output_section_element_dot_assignment(Expression* val) |
| 384 | : val_(val) |
| 385 | { } |
| 386 | |
| 387 | // Finalize the symbol. |
| 388 | void |
| 389 | finalize_symbols(Symbol_table* symtab, const Layout* layout, |
| 390 | uint64_t* dot_value, Output_section** dot_section) |
| 391 | { |
| 392 | *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value, |
| 393 | *dot_section, dot_section); |
| 394 | } |
| 395 | |
| 396 | // Update the dot symbol while setting section addresses. |
| 397 | void |
| 398 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 399 | uint64_t, uint64_t* dot_value, Output_section**, |
| 400 | std::string*, Input_section_list*); |
| 401 | |
| 402 | // Print for debugging. |
| 403 | void |
| 404 | print(FILE* f) const |
| 405 | { |
| 406 | fprintf(f, " . = "); |
| 407 | this->val_->print(f); |
| 408 | fprintf(f, "\n"); |
| 409 | } |
| 410 | |
| 411 | private: |
| 412 | Expression* val_; |
| 413 | }; |
| 414 | |
| 415 | // Update the dot symbol while setting section addresses. |
| 416 | |
| 417 | void |
| 418 | Output_section_element_dot_assignment::set_section_addresses( |
| 419 | Symbol_table* symtab, |
| 420 | Layout* layout, |
| 421 | Output_section* output_section, |
| 422 | uint64_t, |
| 423 | uint64_t* dot_value, |
| 424 | Output_section** dot_section, |
| 425 | std::string* fill, |
| 426 | Input_section_list*) |
| 427 | { |
| 428 | uint64_t next_dot = this->val_->eval_with_dot(symtab, layout, false, |
| 429 | *dot_value, *dot_section, |
| 430 | dot_section); |
| 431 | if (next_dot < *dot_value) |
| 432 | gold_error(_("dot may not move backward")); |
| 433 | if (next_dot > *dot_value && output_section != NULL) |
| 434 | { |
| 435 | section_size_type length = convert_to_section_size_type(next_dot |
| 436 | - *dot_value); |
| 437 | Output_section_data* posd; |
| 438 | if (fill->empty()) |
| 439 | posd = new Output_data_zero_fill(length, 0); |
| 440 | else |
| 441 | { |
| 442 | std::string this_fill = this->get_fill_string(fill, length); |
| 443 | posd = new Output_data_const(this_fill, 0); |
| 444 | } |
| 445 | output_section->add_output_section_data(posd); |
| 446 | } |
| 447 | *dot_value = next_dot; |
| 448 | } |
| 449 | |
| 450 | // An assertion in an output section. |
| 451 | |
| 452 | class Output_section_element_assertion : public Output_section_element |
| 453 | { |
| 454 | public: |
| 455 | Output_section_element_assertion(Expression* check, const char* message, |
| 456 | size_t messagelen) |
| 457 | : assertion_(check, message, messagelen) |
| 458 | { } |
| 459 | |
| 460 | void |
| 461 | print(FILE* f) const |
| 462 | { |
| 463 | fprintf(f, " "); |
| 464 | this->assertion_.print(f); |
| 465 | } |
| 466 | |
| 467 | private: |
| 468 | Script_assertion assertion_; |
| 469 | }; |
| 470 | |
| 471 | // We use a special instance of Output_section_data to handle BYTE, |
| 472 | // SHORT, etc. This permits forward references to symbols in the |
| 473 | // expressions. |
| 474 | |
| 475 | class Output_data_expression : public Output_section_data |
| 476 | { |
| 477 | public: |
| 478 | Output_data_expression(int size, bool is_signed, Expression* val, |
| 479 | const Symbol_table* symtab, const Layout* layout, |
| 480 | uint64_t dot_value, Output_section* dot_section) |
| 481 | : Output_section_data(size, 0), |
| 482 | is_signed_(is_signed), val_(val), symtab_(symtab), |
| 483 | layout_(layout), dot_value_(dot_value), dot_section_(dot_section) |
| 484 | { } |
| 485 | |
| 486 | protected: |
| 487 | // Write the data to the output file. |
| 488 | void |
| 489 | do_write(Output_file*); |
| 490 | |
| 491 | // Write the data to a buffer. |
| 492 | void |
| 493 | do_write_to_buffer(unsigned char*); |
| 494 | |
| 495 | // Write to a map file. |
| 496 | void |
| 497 | do_print_to_mapfile(Mapfile* mapfile) const |
| 498 | { mapfile->print_output_data(this, _("** expression")); } |
| 499 | |
| 500 | private: |
| 501 | template<bool big_endian> |
| 502 | void |
| 503 | endian_write_to_buffer(uint64_t, unsigned char*); |
| 504 | |
| 505 | bool is_signed_; |
| 506 | Expression* val_; |
| 507 | const Symbol_table* symtab_; |
| 508 | const Layout* layout_; |
| 509 | uint64_t dot_value_; |
| 510 | Output_section* dot_section_; |
| 511 | }; |
| 512 | |
| 513 | // Write the data element to the output file. |
| 514 | |
| 515 | void |
| 516 | Output_data_expression::do_write(Output_file* of) |
| 517 | { |
| 518 | unsigned char* view = of->get_output_view(this->offset(), this->data_size()); |
| 519 | this->write_to_buffer(view); |
| 520 | of->write_output_view(this->offset(), this->data_size(), view); |
| 521 | } |
| 522 | |
| 523 | // Write the data element to a buffer. |
| 524 | |
| 525 | void |
| 526 | Output_data_expression::do_write_to_buffer(unsigned char* buf) |
| 527 | { |
| 528 | Output_section* dummy; |
| 529 | uint64_t val = this->val_->eval_with_dot(this->symtab_, this->layout_, |
| 530 | true, this->dot_value_, |
| 531 | this->dot_section_, &dummy); |
| 532 | |
| 533 | if (parameters->target().is_big_endian()) |
| 534 | this->endian_write_to_buffer<true>(val, buf); |
| 535 | else |
| 536 | this->endian_write_to_buffer<false>(val, buf); |
| 537 | } |
| 538 | |
| 539 | template<bool big_endian> |
| 540 | void |
| 541 | Output_data_expression::endian_write_to_buffer(uint64_t val, |
| 542 | unsigned char* buf) |
| 543 | { |
| 544 | switch (this->data_size()) |
| 545 | { |
| 546 | case 1: |
| 547 | elfcpp::Swap_unaligned<8, big_endian>::writeval(buf, val); |
| 548 | break; |
| 549 | case 2: |
| 550 | elfcpp::Swap_unaligned<16, big_endian>::writeval(buf, val); |
| 551 | break; |
| 552 | case 4: |
| 553 | elfcpp::Swap_unaligned<32, big_endian>::writeval(buf, val); |
| 554 | break; |
| 555 | case 8: |
| 556 | if (parameters->target().get_size() == 32) |
| 557 | { |
| 558 | val &= 0xffffffff; |
| 559 | if (this->is_signed_ && (val & 0x80000000) != 0) |
| 560 | val |= 0xffffffff00000000LL; |
| 561 | } |
| 562 | elfcpp::Swap_unaligned<64, big_endian>::writeval(buf, val); |
| 563 | break; |
| 564 | default: |
| 565 | gold_unreachable(); |
| 566 | } |
| 567 | } |
| 568 | |
| 569 | // A data item in an output section. |
| 570 | |
| 571 | class Output_section_element_data : public Output_section_element |
| 572 | { |
| 573 | public: |
| 574 | Output_section_element_data(int size, bool is_signed, Expression* val) |
| 575 | : size_(size), is_signed_(is_signed), val_(val) |
| 576 | { } |
| 577 | |
| 578 | // If there is a data item, then we must create an output section. |
| 579 | bool |
| 580 | needs_output_section() const |
| 581 | { return true; } |
| 582 | |
| 583 | // Finalize symbols--we just need to update dot. |
| 584 | void |
| 585 | finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value, |
| 586 | Output_section**) |
| 587 | { *dot_value += this->size_; } |
| 588 | |
| 589 | // Store the value in the section. |
| 590 | void |
| 591 | set_section_addresses(Symbol_table*, Layout*, Output_section*, uint64_t, |
| 592 | uint64_t* dot_value, Output_section**, std::string*, |
| 593 | Input_section_list*); |
| 594 | |
| 595 | // Print for debugging. |
| 596 | void |
| 597 | print(FILE*) const; |
| 598 | |
| 599 | private: |
| 600 | // The size in bytes. |
| 601 | int size_; |
| 602 | // Whether the value is signed. |
| 603 | bool is_signed_; |
| 604 | // The value. |
| 605 | Expression* val_; |
| 606 | }; |
| 607 | |
| 608 | // Store the value in the section. |
| 609 | |
| 610 | void |
| 611 | Output_section_element_data::set_section_addresses( |
| 612 | Symbol_table* symtab, |
| 613 | Layout* layout, |
| 614 | Output_section* os, |
| 615 | uint64_t, |
| 616 | uint64_t* dot_value, |
| 617 | Output_section** dot_section, |
| 618 | std::string*, |
| 619 | Input_section_list*) |
| 620 | { |
| 621 | gold_assert(os != NULL); |
| 622 | os->add_output_section_data(new Output_data_expression(this->size_, |
| 623 | this->is_signed_, |
| 624 | this->val_, |
| 625 | symtab, |
| 626 | layout, |
| 627 | *dot_value, |
| 628 | *dot_section)); |
| 629 | *dot_value += this->size_; |
| 630 | } |
| 631 | |
| 632 | // Print for debugging. |
| 633 | |
| 634 | void |
| 635 | Output_section_element_data::print(FILE* f) const |
| 636 | { |
| 637 | const char* s; |
| 638 | switch (this->size_) |
| 639 | { |
| 640 | case 1: |
| 641 | s = "BYTE"; |
| 642 | break; |
| 643 | case 2: |
| 644 | s = "SHORT"; |
| 645 | break; |
| 646 | case 4: |
| 647 | s = "LONG"; |
| 648 | break; |
| 649 | case 8: |
| 650 | if (this->is_signed_) |
| 651 | s = "SQUAD"; |
| 652 | else |
| 653 | s = "QUAD"; |
| 654 | break; |
| 655 | default: |
| 656 | gold_unreachable(); |
| 657 | } |
| 658 | fprintf(f, " %s(", s); |
| 659 | this->val_->print(f); |
| 660 | fprintf(f, ")\n"); |
| 661 | } |
| 662 | |
| 663 | // A fill value setting in an output section. |
| 664 | |
| 665 | class Output_section_element_fill : public Output_section_element |
| 666 | { |
| 667 | public: |
| 668 | Output_section_element_fill(Expression* val) |
| 669 | : val_(val) |
| 670 | { } |
| 671 | |
| 672 | // Update the fill value while setting section addresses. |
| 673 | void |
| 674 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 675 | uint64_t, uint64_t* dot_value, |
| 676 | Output_section** dot_section, |
| 677 | std::string* fill, Input_section_list*) |
| 678 | { |
| 679 | Output_section* fill_section; |
| 680 | uint64_t fill_val = this->val_->eval_with_dot(symtab, layout, false, |
| 681 | *dot_value, *dot_section, |
| 682 | &fill_section); |
| 683 | if (fill_section != NULL) |
| 684 | gold_warning(_("fill value is not absolute")); |
| 685 | // FIXME: The GNU linker supports fill values of arbitrary length. |
| 686 | unsigned char fill_buff[4]; |
| 687 | elfcpp::Swap_unaligned<32, true>::writeval(fill_buff, fill_val); |
| 688 | fill->assign(reinterpret_cast<char*>(fill_buff), 4); |
| 689 | } |
| 690 | |
| 691 | // Print for debugging. |
| 692 | void |
| 693 | print(FILE* f) const |
| 694 | { |
| 695 | fprintf(f, " FILL("); |
| 696 | this->val_->print(f); |
| 697 | fprintf(f, ")\n"); |
| 698 | } |
| 699 | |
| 700 | private: |
| 701 | // The new fill value. |
| 702 | Expression* val_; |
| 703 | }; |
| 704 | |
| 705 | // Return whether STRING contains a wildcard character. This is used |
| 706 | // to speed up matching. |
| 707 | |
| 708 | static inline bool |
| 709 | is_wildcard_string(const std::string& s) |
| 710 | { |
| 711 | return strpbrk(s.c_str(), "?*[") != NULL; |
| 712 | } |
| 713 | |
| 714 | // An input section specification in an output section |
| 715 | |
| 716 | class Output_section_element_input : public Output_section_element |
| 717 | { |
| 718 | public: |
| 719 | Output_section_element_input(const Input_section_spec* spec, bool keep); |
| 720 | |
| 721 | // Finalize symbols--just update the value of the dot symbol. |
| 722 | void |
| 723 | finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value, |
| 724 | Output_section** dot_section) |
| 725 | { |
| 726 | *dot_value = this->final_dot_value_; |
| 727 | *dot_section = this->final_dot_section_; |
| 728 | } |
| 729 | |
| 730 | // See whether we match FILE_NAME and SECTION_NAME as an input |
| 731 | // section. |
| 732 | bool |
| 733 | match_name(const char* file_name, const char* section_name) const; |
| 734 | |
| 735 | // Set the section address. |
| 736 | void |
| 737 | set_section_addresses(Symbol_table* symtab, Layout* layout, Output_section*, |
| 738 | uint64_t subalign, uint64_t* dot_value, |
| 739 | Output_section**, std::string* fill, |
| 740 | Input_section_list*); |
| 741 | |
| 742 | // Print for debugging. |
| 743 | void |
| 744 | print(FILE* f) const; |
| 745 | |
| 746 | private: |
| 747 | // An input section pattern. |
| 748 | struct Input_section_pattern |
| 749 | { |
| 750 | std::string pattern; |
| 751 | bool pattern_is_wildcard; |
| 752 | Sort_wildcard sort; |
| 753 | |
| 754 | Input_section_pattern(const char* patterna, size_t patternlena, |
| 755 | Sort_wildcard sorta) |
| 756 | : pattern(patterna, patternlena), |
| 757 | pattern_is_wildcard(is_wildcard_string(this->pattern)), |
| 758 | sort(sorta) |
| 759 | { } |
| 760 | }; |
| 761 | |
| 762 | typedef std::vector<Input_section_pattern> Input_section_patterns; |
| 763 | |
| 764 | // Filename_exclusions is a pair of filename pattern and a bool |
| 765 | // indicating whether the filename is a wildcard. |
| 766 | typedef std::vector<std::pair<std::string, bool> > Filename_exclusions; |
| 767 | |
| 768 | // Return whether STRING matches PATTERN, where IS_WILDCARD_PATTERN |
| 769 | // indicates whether this is a wildcard pattern. |
| 770 | static inline bool |
| 771 | match(const char* string, const char* pattern, bool is_wildcard_pattern) |
| 772 | { |
| 773 | return (is_wildcard_pattern |
| 774 | ? fnmatch(pattern, string, 0) == 0 |
| 775 | : strcmp(string, pattern) == 0); |
| 776 | } |
| 777 | |
| 778 | // See if we match a file name. |
| 779 | bool |
| 780 | match_file_name(const char* file_name) const; |
| 781 | |
| 782 | // The file name pattern. If this is the empty string, we match all |
| 783 | // files. |
| 784 | std::string filename_pattern_; |
| 785 | // Whether the file name pattern is a wildcard. |
| 786 | bool filename_is_wildcard_; |
| 787 | // How the file names should be sorted. This may only be |
| 788 | // SORT_WILDCARD_NONE or SORT_WILDCARD_BY_NAME. |
| 789 | Sort_wildcard filename_sort_; |
| 790 | // The list of file names to exclude. |
| 791 | Filename_exclusions filename_exclusions_; |
| 792 | // The list of input section patterns. |
| 793 | Input_section_patterns input_section_patterns_; |
| 794 | // Whether to keep this section when garbage collecting. |
| 795 | bool keep_; |
| 796 | // The value of dot after including all matching sections. |
| 797 | uint64_t final_dot_value_; |
| 798 | // The section where dot is defined after including all matching |
| 799 | // sections. |
| 800 | Output_section* final_dot_section_; |
| 801 | }; |
| 802 | |
| 803 | // Construct Output_section_element_input. The parser records strings |
| 804 | // as pointers into a copy of the script file, which will go away when |
| 805 | // parsing is complete. We make sure they are in std::string objects. |
| 806 | |
| 807 | Output_section_element_input::Output_section_element_input( |
| 808 | const Input_section_spec* spec, |
| 809 | bool keep) |
| 810 | : filename_pattern_(), |
| 811 | filename_is_wildcard_(false), |
| 812 | filename_sort_(spec->file.sort), |
| 813 | filename_exclusions_(), |
| 814 | input_section_patterns_(), |
| 815 | keep_(keep), |
| 816 | final_dot_value_(0), |
| 817 | final_dot_section_(NULL) |
| 818 | { |
| 819 | // The filename pattern "*" is common, and matches all files. Turn |
| 820 | // it into the empty string. |
| 821 | if (spec->file.name.length != 1 || spec->file.name.value[0] != '*') |
| 822 | this->filename_pattern_.assign(spec->file.name.value, |
| 823 | spec->file.name.length); |
| 824 | this->filename_is_wildcard_ = is_wildcard_string(this->filename_pattern_); |
| 825 | |
| 826 | if (spec->input_sections.exclude != NULL) |
| 827 | { |
| 828 | for (String_list::const_iterator p = |
| 829 | spec->input_sections.exclude->begin(); |
| 830 | p != spec->input_sections.exclude->end(); |
| 831 | ++p) |
| 832 | { |
| 833 | bool is_wildcard = is_wildcard_string(*p); |
| 834 | this->filename_exclusions_.push_back(std::make_pair(*p, |
| 835 | is_wildcard)); |
| 836 | } |
| 837 | } |
| 838 | |
| 839 | if (spec->input_sections.sections != NULL) |
| 840 | { |
| 841 | Input_section_patterns& isp(this->input_section_patterns_); |
| 842 | for (String_sort_list::const_iterator p = |
| 843 | spec->input_sections.sections->begin(); |
| 844 | p != spec->input_sections.sections->end(); |
| 845 | ++p) |
| 846 | isp.push_back(Input_section_pattern(p->name.value, p->name.length, |
| 847 | p->sort)); |
| 848 | } |
| 849 | } |
| 850 | |
| 851 | // See whether we match FILE_NAME. |
| 852 | |
| 853 | bool |
| 854 | Output_section_element_input::match_file_name(const char* file_name) const |
| 855 | { |
| 856 | if (!this->filename_pattern_.empty()) |
| 857 | { |
| 858 | // If we were called with no filename, we refuse to match a |
| 859 | // pattern which requires a file name. |
| 860 | if (file_name == NULL) |
| 861 | return false; |
| 862 | |
| 863 | if (!match(file_name, this->filename_pattern_.c_str(), |
| 864 | this->filename_is_wildcard_)) |
| 865 | return false; |
| 866 | } |
| 867 | |
| 868 | if (file_name != NULL) |
| 869 | { |
| 870 | // Now we have to see whether FILE_NAME matches one of the |
| 871 | // exclusion patterns, if any. |
| 872 | for (Filename_exclusions::const_iterator p = |
| 873 | this->filename_exclusions_.begin(); |
| 874 | p != this->filename_exclusions_.end(); |
| 875 | ++p) |
| 876 | { |
| 877 | if (match(file_name, p->first.c_str(), p->second)) |
| 878 | return false; |
| 879 | } |
| 880 | } |
| 881 | |
| 882 | return true; |
| 883 | } |
| 884 | |
| 885 | // See whether we match FILE_NAME and SECTION_NAME. |
| 886 | |
| 887 | bool |
| 888 | Output_section_element_input::match_name(const char* file_name, |
| 889 | const char* section_name) const |
| 890 | { |
| 891 | if (!this->match_file_name(file_name)) |
| 892 | return false; |
| 893 | |
| 894 | // If there are no section name patterns, then we match. |
| 895 | if (this->input_section_patterns_.empty()) |
| 896 | return true; |
| 897 | |
| 898 | // See whether we match the section name patterns. |
| 899 | for (Input_section_patterns::const_iterator p = |
| 900 | this->input_section_patterns_.begin(); |
| 901 | p != this->input_section_patterns_.end(); |
| 902 | ++p) |
| 903 | { |
| 904 | if (match(section_name, p->pattern.c_str(), p->pattern_is_wildcard)) |
| 905 | return true; |
| 906 | } |
| 907 | |
| 908 | // We didn't match any section names, so we didn't match. |
| 909 | return false; |
| 910 | } |
| 911 | |
| 912 | // Information we use to sort the input sections. |
| 913 | |
| 914 | struct Input_section_info |
| 915 | { |
| 916 | Relobj* relobj; |
| 917 | unsigned int shndx; |
| 918 | std::string section_name; |
| 919 | uint64_t size; |
| 920 | uint64_t addralign; |
| 921 | }; |
| 922 | |
| 923 | // A class to sort the input sections. |
| 924 | |
| 925 | class Input_section_sorter |
| 926 | { |
| 927 | public: |
| 928 | Input_section_sorter(Sort_wildcard filename_sort, Sort_wildcard section_sort) |
| 929 | : filename_sort_(filename_sort), section_sort_(section_sort) |
| 930 | { } |
| 931 | |
| 932 | bool |
| 933 | operator()(const Input_section_info&, const Input_section_info&) const; |
| 934 | |
| 935 | private: |
| 936 | Sort_wildcard filename_sort_; |
| 937 | Sort_wildcard section_sort_; |
| 938 | }; |
| 939 | |
| 940 | bool |
| 941 | Input_section_sorter::operator()(const Input_section_info& isi1, |
| 942 | const Input_section_info& isi2) const |
| 943 | { |
| 944 | if (this->section_sort_ == SORT_WILDCARD_BY_NAME |
| 945 | || this->section_sort_ == SORT_WILDCARD_BY_NAME_BY_ALIGNMENT |
| 946 | || (this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT_BY_NAME |
| 947 | && isi1.addralign == isi2.addralign)) |
| 948 | { |
| 949 | if (isi1.section_name != isi2.section_name) |
| 950 | return isi1.section_name < isi2.section_name; |
| 951 | } |
| 952 | if (this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT |
| 953 | || this->section_sort_ == SORT_WILDCARD_BY_NAME_BY_ALIGNMENT |
| 954 | || this->section_sort_ == SORT_WILDCARD_BY_ALIGNMENT_BY_NAME) |
| 955 | { |
| 956 | if (isi1.addralign != isi2.addralign) |
| 957 | return isi1.addralign < isi2.addralign; |
| 958 | } |
| 959 | if (this->filename_sort_ == SORT_WILDCARD_BY_NAME) |
| 960 | { |
| 961 | if (isi1.relobj->name() != isi2.relobj->name()) |
| 962 | return isi1.relobj->name() < isi2.relobj->name(); |
| 963 | } |
| 964 | |
| 965 | // Otherwise we leave them in the same order. |
| 966 | return false; |
| 967 | } |
| 968 | |
| 969 | // Set the section address. Look in INPUT_SECTIONS for sections which |
| 970 | // match this spec, sort them as specified, and add them to the output |
| 971 | // section. |
| 972 | |
| 973 | void |
| 974 | Output_section_element_input::set_section_addresses( |
| 975 | Symbol_table*, |
| 976 | Layout*, |
| 977 | Output_section* output_section, |
| 978 | uint64_t subalign, |
| 979 | uint64_t* dot_value, |
| 980 | Output_section** dot_section, |
| 981 | std::string* fill, |
| 982 | Input_section_list* input_sections) |
| 983 | { |
| 984 | // We build a list of sections which match each |
| 985 | // Input_section_pattern. |
| 986 | |
| 987 | typedef std::vector<std::vector<Input_section_info> > Matching_sections; |
| 988 | size_t input_pattern_count = this->input_section_patterns_.size(); |
| 989 | if (input_pattern_count == 0) |
| 990 | input_pattern_count = 1; |
| 991 | Matching_sections matching_sections(input_pattern_count); |
| 992 | |
| 993 | // Look through the list of sections for this output section. Add |
| 994 | // each one which matches to one of the elements of |
| 995 | // MATCHING_SECTIONS. |
| 996 | |
| 997 | Input_section_list::iterator p = input_sections->begin(); |
| 998 | while (p != input_sections->end()) |
| 999 | { |
| 1000 | // Calling section_name and section_addralign is not very |
| 1001 | // efficient. |
| 1002 | Input_section_info isi; |
| 1003 | isi.relobj = p->first; |
| 1004 | isi.shndx = p->second; |
| 1005 | |
| 1006 | // Lock the object so that we can get information about the |
| 1007 | // section. This is OK since we know we are single-threaded |
| 1008 | // here. |
| 1009 | { |
| 1010 | const Task* task = reinterpret_cast<const Task*>(-1); |
| 1011 | Task_lock_obj<Object> tl(task, p->first); |
| 1012 | |
| 1013 | isi.section_name = p->first->section_name(p->second); |
| 1014 | isi.size = p->first->section_size(p->second); |
| 1015 | isi.addralign = p->first->section_addralign(p->second); |
| 1016 | } |
| 1017 | |
| 1018 | if (!this->match_file_name(isi.relobj->name().c_str())) |
| 1019 | ++p; |
| 1020 | else if (this->input_section_patterns_.empty()) |
| 1021 | { |
| 1022 | matching_sections[0].push_back(isi); |
| 1023 | p = input_sections->erase(p); |
| 1024 | } |
| 1025 | else |
| 1026 | { |
| 1027 | size_t i; |
| 1028 | for (i = 0; i < input_pattern_count; ++i) |
| 1029 | { |
| 1030 | const Input_section_pattern& |
| 1031 | isp(this->input_section_patterns_[i]); |
| 1032 | if (match(isi.section_name.c_str(), isp.pattern.c_str(), |
| 1033 | isp.pattern_is_wildcard)) |
| 1034 | break; |
| 1035 | } |
| 1036 | |
| 1037 | if (i >= this->input_section_patterns_.size()) |
| 1038 | ++p; |
| 1039 | else |
| 1040 | { |
| 1041 | matching_sections[i].push_back(isi); |
| 1042 | p = input_sections->erase(p); |
| 1043 | } |
| 1044 | } |
| 1045 | } |
| 1046 | |
| 1047 | // Look through MATCHING_SECTIONS. Sort each one as specified, |
| 1048 | // using a stable sort so that we get the default order when |
| 1049 | // sections are otherwise equal. Add each input section to the |
| 1050 | // output section. |
| 1051 | |
| 1052 | for (size_t i = 0; i < input_pattern_count; ++i) |
| 1053 | { |
| 1054 | if (matching_sections[i].empty()) |
| 1055 | continue; |
| 1056 | |
| 1057 | gold_assert(output_section != NULL); |
| 1058 | |
| 1059 | const Input_section_pattern& isp(this->input_section_patterns_[i]); |
| 1060 | if (isp.sort != SORT_WILDCARD_NONE |
| 1061 | || this->filename_sort_ != SORT_WILDCARD_NONE) |
| 1062 | std::stable_sort(matching_sections[i].begin(), |
| 1063 | matching_sections[i].end(), |
| 1064 | Input_section_sorter(this->filename_sort_, |
| 1065 | isp.sort)); |
| 1066 | |
| 1067 | for (std::vector<Input_section_info>::const_iterator p = |
| 1068 | matching_sections[i].begin(); |
| 1069 | p != matching_sections[i].end(); |
| 1070 | ++p) |
| 1071 | { |
| 1072 | uint64_t this_subalign = p->addralign; |
| 1073 | if (this_subalign < subalign) |
| 1074 | this_subalign = subalign; |
| 1075 | |
| 1076 | uint64_t address = align_address(*dot_value, this_subalign); |
| 1077 | |
| 1078 | if (address > *dot_value && !fill->empty()) |
| 1079 | { |
| 1080 | section_size_type length = |
| 1081 | convert_to_section_size_type(address - *dot_value); |
| 1082 | std::string this_fill = this->get_fill_string(fill, length); |
| 1083 | Output_section_data* posd = new Output_data_const(this_fill, 0); |
| 1084 | output_section->add_output_section_data(posd); |
| 1085 | } |
| 1086 | |
| 1087 | output_section->add_input_section_for_script(p->relobj, |
| 1088 | p->shndx, |
| 1089 | p->size, |
| 1090 | this_subalign); |
| 1091 | |
| 1092 | *dot_value = address + p->size; |
| 1093 | } |
| 1094 | } |
| 1095 | |
| 1096 | this->final_dot_value_ = *dot_value; |
| 1097 | this->final_dot_section_ = *dot_section; |
| 1098 | } |
| 1099 | |
| 1100 | // Print for debugging. |
| 1101 | |
| 1102 | void |
| 1103 | Output_section_element_input::print(FILE* f) const |
| 1104 | { |
| 1105 | fprintf(f, " "); |
| 1106 | |
| 1107 | if (this->keep_) |
| 1108 | fprintf(f, "KEEP("); |
| 1109 | |
| 1110 | if (!this->filename_pattern_.empty()) |
| 1111 | { |
| 1112 | bool need_close_paren = false; |
| 1113 | switch (this->filename_sort_) |
| 1114 | { |
| 1115 | case SORT_WILDCARD_NONE: |
| 1116 | break; |
| 1117 | case SORT_WILDCARD_BY_NAME: |
| 1118 | fprintf(f, "SORT_BY_NAME("); |
| 1119 | need_close_paren = true; |
| 1120 | break; |
| 1121 | default: |
| 1122 | gold_unreachable(); |
| 1123 | } |
| 1124 | |
| 1125 | fprintf(f, "%s", this->filename_pattern_.c_str()); |
| 1126 | |
| 1127 | if (need_close_paren) |
| 1128 | fprintf(f, ")"); |
| 1129 | } |
| 1130 | |
| 1131 | if (!this->input_section_patterns_.empty() |
| 1132 | || !this->filename_exclusions_.empty()) |
| 1133 | { |
| 1134 | fprintf(f, "("); |
| 1135 | |
| 1136 | bool need_space = false; |
| 1137 | if (!this->filename_exclusions_.empty()) |
| 1138 | { |
| 1139 | fprintf(f, "EXCLUDE_FILE("); |
| 1140 | bool need_comma = false; |
| 1141 | for (Filename_exclusions::const_iterator p = |
| 1142 | this->filename_exclusions_.begin(); |
| 1143 | p != this->filename_exclusions_.end(); |
| 1144 | ++p) |
| 1145 | { |
| 1146 | if (need_comma) |
| 1147 | fprintf(f, ", "); |
| 1148 | fprintf(f, "%s", p->first.c_str()); |
| 1149 | need_comma = true; |
| 1150 | } |
| 1151 | fprintf(f, ")"); |
| 1152 | need_space = true; |
| 1153 | } |
| 1154 | |
| 1155 | for (Input_section_patterns::const_iterator p = |
| 1156 | this->input_section_patterns_.begin(); |
| 1157 | p != this->input_section_patterns_.end(); |
| 1158 | ++p) |
| 1159 | { |
| 1160 | if (need_space) |
| 1161 | fprintf(f, " "); |
| 1162 | |
| 1163 | int close_parens = 0; |
| 1164 | switch (p->sort) |
| 1165 | { |
| 1166 | case SORT_WILDCARD_NONE: |
| 1167 | break; |
| 1168 | case SORT_WILDCARD_BY_NAME: |
| 1169 | fprintf(f, "SORT_BY_NAME("); |
| 1170 | close_parens = 1; |
| 1171 | break; |
| 1172 | case SORT_WILDCARD_BY_ALIGNMENT: |
| 1173 | fprintf(f, "SORT_BY_ALIGNMENT("); |
| 1174 | close_parens = 1; |
| 1175 | break; |
| 1176 | case SORT_WILDCARD_BY_NAME_BY_ALIGNMENT: |
| 1177 | fprintf(f, "SORT_BY_NAME(SORT_BY_ALIGNMENT("); |
| 1178 | close_parens = 2; |
| 1179 | break; |
| 1180 | case SORT_WILDCARD_BY_ALIGNMENT_BY_NAME: |
| 1181 | fprintf(f, "SORT_BY_ALIGNMENT(SORT_BY_NAME("); |
| 1182 | close_parens = 2; |
| 1183 | break; |
| 1184 | default: |
| 1185 | gold_unreachable(); |
| 1186 | } |
| 1187 | |
| 1188 | fprintf(f, "%s", p->pattern.c_str()); |
| 1189 | |
| 1190 | for (int i = 0; i < close_parens; ++i) |
| 1191 | fprintf(f, ")"); |
| 1192 | |
| 1193 | need_space = true; |
| 1194 | } |
| 1195 | |
| 1196 | fprintf(f, ")"); |
| 1197 | } |
| 1198 | |
| 1199 | if (this->keep_) |
| 1200 | fprintf(f, ")"); |
| 1201 | |
| 1202 | fprintf(f, "\n"); |
| 1203 | } |
| 1204 | |
| 1205 | // An output section. |
| 1206 | |
| 1207 | class Output_section_definition : public Sections_element |
| 1208 | { |
| 1209 | public: |
| 1210 | typedef Output_section_element::Input_section_list Input_section_list; |
| 1211 | |
| 1212 | Output_section_definition(const char* name, size_t namelen, |
| 1213 | const Parser_output_section_header* header); |
| 1214 | |
| 1215 | // Finish the output section with the information in the trailer. |
| 1216 | void |
| 1217 | finish(const Parser_output_section_trailer* trailer); |
| 1218 | |
| 1219 | // Add a symbol to be defined. |
| 1220 | void |
| 1221 | add_symbol_assignment(const char* name, size_t length, Expression* value, |
| 1222 | bool provide, bool hidden); |
| 1223 | |
| 1224 | // Add an assignment to the special dot symbol. |
| 1225 | void |
| 1226 | add_dot_assignment(Expression* value); |
| 1227 | |
| 1228 | // Add an assertion. |
| 1229 | void |
| 1230 | add_assertion(Expression* check, const char* message, size_t messagelen); |
| 1231 | |
| 1232 | // Add a data item to the current output section. |
| 1233 | void |
| 1234 | add_data(int size, bool is_signed, Expression* val); |
| 1235 | |
| 1236 | // Add a setting for the fill value. |
| 1237 | void |
| 1238 | add_fill(Expression* val); |
| 1239 | |
| 1240 | // Add an input section specification. |
| 1241 | void |
| 1242 | add_input_section(const Input_section_spec* spec, bool keep); |
| 1243 | |
| 1244 | // Record that the output section is relro. |
| 1245 | void |
| 1246 | set_is_relro() |
| 1247 | { this->is_relro_ = true; } |
| 1248 | |
| 1249 | // Create any required output sections. |
| 1250 | void |
| 1251 | create_sections(Layout*); |
| 1252 | |
| 1253 | // Add any symbols being defined to the symbol table. |
| 1254 | void |
| 1255 | add_symbols_to_table(Symbol_table* symtab); |
| 1256 | |
| 1257 | // Finalize symbols and check assertions. |
| 1258 | void |
| 1259 | finalize_symbols(Symbol_table*, const Layout*, uint64_t*); |
| 1260 | |
| 1261 | // Return the output section name to use for an input file name and |
| 1262 | // section name. |
| 1263 | const char* |
| 1264 | output_section_name(const char* file_name, const char* section_name, |
| 1265 | Output_section***); |
| 1266 | |
| 1267 | // Return whether to place an orphan section after this one. |
| 1268 | bool |
| 1269 | place_orphan_here(const Output_section *os, bool* exact, bool*) const; |
| 1270 | |
| 1271 | // Set the section address. |
| 1272 | void |
| 1273 | set_section_addresses(Symbol_table* symtab, Layout* layout, |
| 1274 | uint64_t* dot_value, uint64_t* load_address); |
| 1275 | |
| 1276 | // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| 1277 | // this section is constrained, and the input sections do not match, |
| 1278 | // return the constraint, and set *POSD. |
| 1279 | Section_constraint |
| 1280 | check_constraint(Output_section_definition** posd); |
| 1281 | |
| 1282 | // See if this is the alternate output section for a constrained |
| 1283 | // output section. If it is, transfer the Output_section and return |
| 1284 | // true. Otherwise return false. |
| 1285 | bool |
| 1286 | alternate_constraint(Output_section_definition*, Section_constraint); |
| 1287 | |
| 1288 | // Get the list of segments to use for an allocated section when |
| 1289 | // using a PHDRS clause. |
| 1290 | Output_section* |
| 1291 | allocate_to_segment(String_list** phdrs_list, bool* orphan); |
| 1292 | |
| 1293 | // Look for an output section by name and return the address, the |
| 1294 | // load address, the alignment, and the size. This is used when an |
| 1295 | // expression refers to an output section which was not actually |
| 1296 | // created. This returns true if the section was found, false |
| 1297 | // otherwise. |
| 1298 | bool |
| 1299 | get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*, |
| 1300 | uint64_t*) const; |
| 1301 | |
| 1302 | // Return the associated Output_section if there is one. |
| 1303 | Output_section* |
| 1304 | get_output_section() const |
| 1305 | { return this->output_section_; } |
| 1306 | |
| 1307 | // Print the contents to the FILE. This is for debugging. |
| 1308 | void |
| 1309 | print(FILE*) const; |
| 1310 | |
| 1311 | private: |
| 1312 | typedef std::vector<Output_section_element*> Output_section_elements; |
| 1313 | |
| 1314 | // The output section name. |
| 1315 | std::string name_; |
| 1316 | // The address. This may be NULL. |
| 1317 | Expression* address_; |
| 1318 | // The load address. This may be NULL. |
| 1319 | Expression* load_address_; |
| 1320 | // The alignment. This may be NULL. |
| 1321 | Expression* align_; |
| 1322 | // The input section alignment. This may be NULL. |
| 1323 | Expression* subalign_; |
| 1324 | // The constraint, if any. |
| 1325 | Section_constraint constraint_; |
| 1326 | // The fill value. This may be NULL. |
| 1327 | Expression* fill_; |
| 1328 | // The list of segments this section should go into. This may be |
| 1329 | // NULL. |
| 1330 | String_list* phdrs_; |
| 1331 | // The list of elements defining the section. |
| 1332 | Output_section_elements elements_; |
| 1333 | // The Output_section created for this definition. This will be |
| 1334 | // NULL if none was created. |
| 1335 | Output_section* output_section_; |
| 1336 | // The address after it has been evaluated. |
| 1337 | uint64_t evaluated_address_; |
| 1338 | // The load address after it has been evaluated. |
| 1339 | uint64_t evaluated_load_address_; |
| 1340 | // The alignment after it has been evaluated. |
| 1341 | uint64_t evaluated_addralign_; |
| 1342 | // The output section is relro. |
| 1343 | bool is_relro_; |
| 1344 | }; |
| 1345 | |
| 1346 | // Constructor. |
| 1347 | |
| 1348 | Output_section_definition::Output_section_definition( |
| 1349 | const char* name, |
| 1350 | size_t namelen, |
| 1351 | const Parser_output_section_header* header) |
| 1352 | : name_(name, namelen), |
| 1353 | address_(header->address), |
| 1354 | load_address_(header->load_address), |
| 1355 | align_(header->align), |
| 1356 | subalign_(header->subalign), |
| 1357 | constraint_(header->constraint), |
| 1358 | fill_(NULL), |
| 1359 | phdrs_(NULL), |
| 1360 | elements_(), |
| 1361 | output_section_(NULL), |
| 1362 | evaluated_address_(0), |
| 1363 | evaluated_load_address_(0), |
| 1364 | evaluated_addralign_(0), |
| 1365 | is_relro_(false) |
| 1366 | { |
| 1367 | } |
| 1368 | |
| 1369 | // Finish an output section. |
| 1370 | |
| 1371 | void |
| 1372 | Output_section_definition::finish(const Parser_output_section_trailer* trailer) |
| 1373 | { |
| 1374 | this->fill_ = trailer->fill; |
| 1375 | this->phdrs_ = trailer->phdrs; |
| 1376 | } |
| 1377 | |
| 1378 | // Add a symbol to be defined. |
| 1379 | |
| 1380 | void |
| 1381 | Output_section_definition::add_symbol_assignment(const char* name, |
| 1382 | size_t length, |
| 1383 | Expression* value, |
| 1384 | bool provide, |
| 1385 | bool hidden) |
| 1386 | { |
| 1387 | Output_section_element* p = new Output_section_element_assignment(name, |
| 1388 | length, |
| 1389 | value, |
| 1390 | provide, |
| 1391 | hidden); |
| 1392 | this->elements_.push_back(p); |
| 1393 | } |
| 1394 | |
| 1395 | // Add an assignment to the special dot symbol. |
| 1396 | |
| 1397 | void |
| 1398 | Output_section_definition::add_dot_assignment(Expression* value) |
| 1399 | { |
| 1400 | Output_section_element* p = new Output_section_element_dot_assignment(value); |
| 1401 | this->elements_.push_back(p); |
| 1402 | } |
| 1403 | |
| 1404 | // Add an assertion. |
| 1405 | |
| 1406 | void |
| 1407 | Output_section_definition::add_assertion(Expression* check, |
| 1408 | const char* message, |
| 1409 | size_t messagelen) |
| 1410 | { |
| 1411 | Output_section_element* p = new Output_section_element_assertion(check, |
| 1412 | message, |
| 1413 | messagelen); |
| 1414 | this->elements_.push_back(p); |
| 1415 | } |
| 1416 | |
| 1417 | // Add a data item to the current output section. |
| 1418 | |
| 1419 | void |
| 1420 | Output_section_definition::add_data(int size, bool is_signed, Expression* val) |
| 1421 | { |
| 1422 | Output_section_element* p = new Output_section_element_data(size, is_signed, |
| 1423 | val); |
| 1424 | this->elements_.push_back(p); |
| 1425 | } |
| 1426 | |
| 1427 | // Add a setting for the fill value. |
| 1428 | |
| 1429 | void |
| 1430 | Output_section_definition::add_fill(Expression* val) |
| 1431 | { |
| 1432 | Output_section_element* p = new Output_section_element_fill(val); |
| 1433 | this->elements_.push_back(p); |
| 1434 | } |
| 1435 | |
| 1436 | // Add an input section specification. |
| 1437 | |
| 1438 | void |
| 1439 | Output_section_definition::add_input_section(const Input_section_spec* spec, |
| 1440 | bool keep) |
| 1441 | { |
| 1442 | Output_section_element* p = new Output_section_element_input(spec, keep); |
| 1443 | this->elements_.push_back(p); |
| 1444 | } |
| 1445 | |
| 1446 | // Create any required output sections. We need an output section if |
| 1447 | // there is a data statement here. |
| 1448 | |
| 1449 | void |
| 1450 | Output_section_definition::create_sections(Layout* layout) |
| 1451 | { |
| 1452 | if (this->output_section_ != NULL) |
| 1453 | return; |
| 1454 | for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| 1455 | p != this->elements_.end(); |
| 1456 | ++p) |
| 1457 | { |
| 1458 | if ((*p)->needs_output_section()) |
| 1459 | { |
| 1460 | const char* name = this->name_.c_str(); |
| 1461 | this->output_section_ = layout->make_output_section_for_script(name); |
| 1462 | return; |
| 1463 | } |
| 1464 | } |
| 1465 | } |
| 1466 | |
| 1467 | // Add any symbols being defined to the symbol table. |
| 1468 | |
| 1469 | void |
| 1470 | Output_section_definition::add_symbols_to_table(Symbol_table* symtab) |
| 1471 | { |
| 1472 | for (Output_section_elements::iterator p = this->elements_.begin(); |
| 1473 | p != this->elements_.end(); |
| 1474 | ++p) |
| 1475 | (*p)->add_symbols_to_table(symtab); |
| 1476 | } |
| 1477 | |
| 1478 | // Finalize symbols and check assertions. |
| 1479 | |
| 1480 | void |
| 1481 | Output_section_definition::finalize_symbols(Symbol_table* symtab, |
| 1482 | const Layout* layout, |
| 1483 | uint64_t* dot_value) |
| 1484 | { |
| 1485 | if (this->output_section_ != NULL) |
| 1486 | *dot_value = this->output_section_->address(); |
| 1487 | else |
| 1488 | { |
| 1489 | uint64_t address = *dot_value; |
| 1490 | if (this->address_ != NULL) |
| 1491 | { |
| 1492 | Output_section* dummy; |
| 1493 | address = this->address_->eval_with_dot(symtab, layout, true, |
| 1494 | *dot_value, NULL, |
| 1495 | &dummy); |
| 1496 | } |
| 1497 | if (this->align_ != NULL) |
| 1498 | { |
| 1499 | Output_section* dummy; |
| 1500 | uint64_t align = this->align_->eval_with_dot(symtab, layout, true, |
| 1501 | *dot_value, |
| 1502 | NULL, |
| 1503 | &dummy); |
| 1504 | address = align_address(address, align); |
| 1505 | } |
| 1506 | *dot_value = address; |
| 1507 | } |
| 1508 | |
| 1509 | Output_section* dot_section = this->output_section_; |
| 1510 | for (Output_section_elements::iterator p = this->elements_.begin(); |
| 1511 | p != this->elements_.end(); |
| 1512 | ++p) |
| 1513 | (*p)->finalize_symbols(symtab, layout, dot_value, &dot_section); |
| 1514 | } |
| 1515 | |
| 1516 | // Return the output section name to use for an input section name. |
| 1517 | |
| 1518 | const char* |
| 1519 | Output_section_definition::output_section_name(const char* file_name, |
| 1520 | const char* section_name, |
| 1521 | Output_section*** slot) |
| 1522 | { |
| 1523 | // Ask each element whether it matches NAME. |
| 1524 | for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| 1525 | p != this->elements_.end(); |
| 1526 | ++p) |
| 1527 | { |
| 1528 | if ((*p)->match_name(file_name, section_name)) |
| 1529 | { |
| 1530 | // We found a match for NAME, which means that it should go |
| 1531 | // into this output section. |
| 1532 | *slot = &this->output_section_; |
| 1533 | return this->name_.c_str(); |
| 1534 | } |
| 1535 | } |
| 1536 | |
| 1537 | // We don't know about this section name. |
| 1538 | return NULL; |
| 1539 | } |
| 1540 | |
| 1541 | // Return whether to place an orphan output section after this |
| 1542 | // section. |
| 1543 | |
| 1544 | bool |
| 1545 | Output_section_definition::place_orphan_here(const Output_section *os, |
| 1546 | bool* exact, |
| 1547 | bool* is_relro) const |
| 1548 | { |
| 1549 | *is_relro = this->is_relro_; |
| 1550 | |
| 1551 | // Check for the simple case first. |
| 1552 | if (this->output_section_ != NULL |
| 1553 | && this->output_section_->type() == os->type() |
| 1554 | && this->output_section_->flags() == os->flags()) |
| 1555 | { |
| 1556 | *exact = true; |
| 1557 | return true; |
| 1558 | } |
| 1559 | |
| 1560 | // Otherwise use some heuristics. |
| 1561 | |
| 1562 | if ((os->flags() & elfcpp::SHF_ALLOC) == 0) |
| 1563 | return false; |
| 1564 | |
| 1565 | if (os->type() == elfcpp::SHT_NOBITS) |
| 1566 | { |
| 1567 | if (this->name_ == ".bss") |
| 1568 | { |
| 1569 | *exact = true; |
| 1570 | return true; |
| 1571 | } |
| 1572 | if (this->output_section_ != NULL |
| 1573 | && this->output_section_->type() == elfcpp::SHT_NOBITS) |
| 1574 | return true; |
| 1575 | } |
| 1576 | else if (os->type() == elfcpp::SHT_NOTE) |
| 1577 | { |
| 1578 | if (this->output_section_ != NULL |
| 1579 | && this->output_section_->type() == elfcpp::SHT_NOTE) |
| 1580 | { |
| 1581 | *exact = true; |
| 1582 | return true; |
| 1583 | } |
| 1584 | if (this->name_.compare(0, 5, ".note") == 0) |
| 1585 | { |
| 1586 | *exact = true; |
| 1587 | return true; |
| 1588 | } |
| 1589 | if (this->name_ == ".interp") |
| 1590 | return true; |
| 1591 | if (this->output_section_ != NULL |
| 1592 | && this->output_section_->type() == elfcpp::SHT_PROGBITS |
| 1593 | && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0) |
| 1594 | return true; |
| 1595 | } |
| 1596 | else if (os->type() == elfcpp::SHT_REL || os->type() == elfcpp::SHT_RELA) |
| 1597 | { |
| 1598 | if (this->name_.compare(0, 4, ".rel") == 0) |
| 1599 | { |
| 1600 | *exact = true; |
| 1601 | return true; |
| 1602 | } |
| 1603 | if (this->output_section_ != NULL |
| 1604 | && (this->output_section_->type() == elfcpp::SHT_REL |
| 1605 | || this->output_section_->type() == elfcpp::SHT_RELA)) |
| 1606 | { |
| 1607 | *exact = true; |
| 1608 | return true; |
| 1609 | } |
| 1610 | if (this->output_section_ != NULL |
| 1611 | && this->output_section_->type() == elfcpp::SHT_PROGBITS |
| 1612 | && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0) |
| 1613 | return true; |
| 1614 | } |
| 1615 | else if (os->type() == elfcpp::SHT_PROGBITS |
| 1616 | && (os->flags() & elfcpp::SHF_WRITE) != 0) |
| 1617 | { |
| 1618 | if (this->name_ == ".data") |
| 1619 | { |
| 1620 | *exact = true; |
| 1621 | return true; |
| 1622 | } |
| 1623 | if (this->output_section_ != NULL |
| 1624 | && this->output_section_->type() == elfcpp::SHT_PROGBITS |
| 1625 | && (this->output_section_->flags() & elfcpp::SHF_WRITE) != 0) |
| 1626 | return true; |
| 1627 | } |
| 1628 | else if (os->type() == elfcpp::SHT_PROGBITS |
| 1629 | && (os->flags() & elfcpp::SHF_EXECINSTR) != 0) |
| 1630 | { |
| 1631 | if (this->name_ == ".text") |
| 1632 | { |
| 1633 | *exact = true; |
| 1634 | return true; |
| 1635 | } |
| 1636 | if (this->output_section_ != NULL |
| 1637 | && this->output_section_->type() == elfcpp::SHT_PROGBITS |
| 1638 | && (this->output_section_->flags() & elfcpp::SHF_EXECINSTR) != 0) |
| 1639 | return true; |
| 1640 | } |
| 1641 | else if (os->type() == elfcpp::SHT_PROGBITS |
| 1642 | || (os->type() != elfcpp::SHT_PROGBITS |
| 1643 | && (os->flags() & elfcpp::SHF_WRITE) == 0)) |
| 1644 | { |
| 1645 | if (this->name_ == ".rodata") |
| 1646 | { |
| 1647 | *exact = true; |
| 1648 | return true; |
| 1649 | } |
| 1650 | if (this->output_section_ != NULL |
| 1651 | && this->output_section_->type() == elfcpp::SHT_PROGBITS |
| 1652 | && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0) |
| 1653 | return true; |
| 1654 | } |
| 1655 | |
| 1656 | return false; |
| 1657 | } |
| 1658 | |
| 1659 | // Set the section address. Note that the OUTPUT_SECTION_ field will |
| 1660 | // be NULL if no input sections were mapped to this output section. |
| 1661 | // We still have to adjust dot and process symbol assignments. |
| 1662 | |
| 1663 | void |
| 1664 | Output_section_definition::set_section_addresses(Symbol_table* symtab, |
| 1665 | Layout* layout, |
| 1666 | uint64_t* dot_value, |
| 1667 | uint64_t* load_address) |
| 1668 | { |
| 1669 | uint64_t address; |
| 1670 | if (this->address_ == NULL) |
| 1671 | address = *dot_value; |
| 1672 | else |
| 1673 | { |
| 1674 | Output_section* dummy; |
| 1675 | address = this->address_->eval_with_dot(symtab, layout, true, |
| 1676 | *dot_value, NULL, &dummy); |
| 1677 | } |
| 1678 | |
| 1679 | uint64_t align; |
| 1680 | if (this->align_ == NULL) |
| 1681 | { |
| 1682 | if (this->output_section_ == NULL) |
| 1683 | align = 0; |
| 1684 | else |
| 1685 | align = this->output_section_->addralign(); |
| 1686 | } |
| 1687 | else |
| 1688 | { |
| 1689 | Output_section* align_section; |
| 1690 | align = this->align_->eval_with_dot(symtab, layout, true, *dot_value, |
| 1691 | NULL, &align_section); |
| 1692 | if (align_section != NULL) |
| 1693 | gold_warning(_("alignment of section %s is not absolute"), |
| 1694 | this->name_.c_str()); |
| 1695 | if (this->output_section_ != NULL) |
| 1696 | this->output_section_->set_addralign(align); |
| 1697 | } |
| 1698 | |
| 1699 | address = align_address(address, align); |
| 1700 | |
| 1701 | uint64_t start_address = address; |
| 1702 | |
| 1703 | *dot_value = address; |
| 1704 | |
| 1705 | // The address of non-SHF_ALLOC sections is forced to zero, |
| 1706 | // regardless of what the linker script wants. |
| 1707 | if (this->output_section_ != NULL |
| 1708 | && (this->output_section_->flags() & elfcpp::SHF_ALLOC) != 0) |
| 1709 | this->output_section_->set_address(address); |
| 1710 | |
| 1711 | this->evaluated_address_ = address; |
| 1712 | this->evaluated_addralign_ = align; |
| 1713 | |
| 1714 | if (this->load_address_ == NULL) |
| 1715 | this->evaluated_load_address_ = address; |
| 1716 | else |
| 1717 | { |
| 1718 | Output_section* dummy; |
| 1719 | uint64_t load_address = |
| 1720 | this->load_address_->eval_with_dot(symtab, layout, true, *dot_value, |
| 1721 | this->output_section_, &dummy); |
| 1722 | if (this->output_section_ != NULL) |
| 1723 | this->output_section_->set_load_address(load_address); |
| 1724 | this->evaluated_load_address_ = load_address; |
| 1725 | } |
| 1726 | |
| 1727 | uint64_t subalign; |
| 1728 | if (this->subalign_ == NULL) |
| 1729 | subalign = 0; |
| 1730 | else |
| 1731 | { |
| 1732 | Output_section* subalign_section; |
| 1733 | subalign = this->subalign_->eval_with_dot(symtab, layout, true, |
| 1734 | *dot_value, NULL, |
| 1735 | &subalign_section); |
| 1736 | if (subalign_section != NULL) |
| 1737 | gold_warning(_("subalign of section %s is not absolute"), |
| 1738 | this->name_.c_str()); |
| 1739 | } |
| 1740 | |
| 1741 | std::string fill; |
| 1742 | if (this->fill_ != NULL) |
| 1743 | { |
| 1744 | // FIXME: The GNU linker supports fill values of arbitrary |
| 1745 | // length. |
| 1746 | Output_section* fill_section; |
| 1747 | uint64_t fill_val = this->fill_->eval_with_dot(symtab, layout, true, |
| 1748 | *dot_value, |
| 1749 | NULL, |
| 1750 | &fill_section); |
| 1751 | if (fill_section != NULL) |
| 1752 | gold_warning(_("fill of section %s is not absolute"), |
| 1753 | this->name_.c_str()); |
| 1754 | unsigned char fill_buff[4]; |
| 1755 | elfcpp::Swap_unaligned<32, true>::writeval(fill_buff, fill_val); |
| 1756 | fill.assign(reinterpret_cast<char*>(fill_buff), 4); |
| 1757 | } |
| 1758 | |
| 1759 | Input_section_list input_sections; |
| 1760 | if (this->output_section_ != NULL) |
| 1761 | { |
| 1762 | // Get the list of input sections attached to this output |
| 1763 | // section. This will leave the output section with only |
| 1764 | // Output_section_data entries. |
| 1765 | address += this->output_section_->get_input_sections(address, |
| 1766 | fill, |
| 1767 | &input_sections); |
| 1768 | *dot_value = address; |
| 1769 | } |
| 1770 | |
| 1771 | Output_section* dot_section = this->output_section_; |
| 1772 | for (Output_section_elements::iterator p = this->elements_.begin(); |
| 1773 | p != this->elements_.end(); |
| 1774 | ++p) |
| 1775 | (*p)->set_section_addresses(symtab, layout, this->output_section_, |
| 1776 | subalign, dot_value, &dot_section, &fill, |
| 1777 | &input_sections); |
| 1778 | |
| 1779 | gold_assert(input_sections.empty()); |
| 1780 | |
| 1781 | if (this->load_address_ == NULL || this->output_section_ == NULL) |
| 1782 | *load_address = *dot_value; |
| 1783 | else |
| 1784 | *load_address = (this->output_section_->load_address() |
| 1785 | + (*dot_value - start_address)); |
| 1786 | |
| 1787 | if (this->output_section_ != NULL) |
| 1788 | { |
| 1789 | if (this->is_relro_) |
| 1790 | this->output_section_->set_is_relro(); |
| 1791 | else |
| 1792 | this->output_section_->clear_is_relro(); |
| 1793 | } |
| 1794 | } |
| 1795 | |
| 1796 | // Check a constraint (ONLY_IF_RO, etc.) on an output section. If |
| 1797 | // this section is constrained, and the input sections do not match, |
| 1798 | // return the constraint, and set *POSD. |
| 1799 | |
| 1800 | Section_constraint |
| 1801 | Output_section_definition::check_constraint(Output_section_definition** posd) |
| 1802 | { |
| 1803 | switch (this->constraint_) |
| 1804 | { |
| 1805 | case CONSTRAINT_NONE: |
| 1806 | return CONSTRAINT_NONE; |
| 1807 | |
| 1808 | case CONSTRAINT_ONLY_IF_RO: |
| 1809 | if (this->output_section_ != NULL |
| 1810 | && (this->output_section_->flags() & elfcpp::SHF_WRITE) != 0) |
| 1811 | { |
| 1812 | *posd = this; |
| 1813 | return CONSTRAINT_ONLY_IF_RO; |
| 1814 | } |
| 1815 | return CONSTRAINT_NONE; |
| 1816 | |
| 1817 | case CONSTRAINT_ONLY_IF_RW: |
| 1818 | if (this->output_section_ != NULL |
| 1819 | && (this->output_section_->flags() & elfcpp::SHF_WRITE) == 0) |
| 1820 | { |
| 1821 | *posd = this; |
| 1822 | return CONSTRAINT_ONLY_IF_RW; |
| 1823 | } |
| 1824 | return CONSTRAINT_NONE; |
| 1825 | |
| 1826 | case CONSTRAINT_SPECIAL: |
| 1827 | if (this->output_section_ != NULL) |
| 1828 | gold_error(_("SPECIAL constraints are not implemented")); |
| 1829 | return CONSTRAINT_NONE; |
| 1830 | |
| 1831 | default: |
| 1832 | gold_unreachable(); |
| 1833 | } |
| 1834 | } |
| 1835 | |
| 1836 | // See if this is the alternate output section for a constrained |
| 1837 | // output section. If it is, transfer the Output_section and return |
| 1838 | // true. Otherwise return false. |
| 1839 | |
| 1840 | bool |
| 1841 | Output_section_definition::alternate_constraint( |
| 1842 | Output_section_definition* posd, |
| 1843 | Section_constraint constraint) |
| 1844 | { |
| 1845 | if (this->name_ != posd->name_) |
| 1846 | return false; |
| 1847 | |
| 1848 | switch (constraint) |
| 1849 | { |
| 1850 | case CONSTRAINT_ONLY_IF_RO: |
| 1851 | if (this->constraint_ != CONSTRAINT_ONLY_IF_RW) |
| 1852 | return false; |
| 1853 | break; |
| 1854 | |
| 1855 | case CONSTRAINT_ONLY_IF_RW: |
| 1856 | if (this->constraint_ != CONSTRAINT_ONLY_IF_RO) |
| 1857 | return false; |
| 1858 | break; |
| 1859 | |
| 1860 | default: |
| 1861 | gold_unreachable(); |
| 1862 | } |
| 1863 | |
| 1864 | // We have found the alternate constraint. We just need to move |
| 1865 | // over the Output_section. When constraints are used properly, |
| 1866 | // THIS should not have an output_section pointer, as all the input |
| 1867 | // sections should have matched the other definition. |
| 1868 | |
| 1869 | if (this->output_section_ != NULL) |
| 1870 | gold_error(_("mismatched definition for constrained sections")); |
| 1871 | |
| 1872 | this->output_section_ = posd->output_section_; |
| 1873 | posd->output_section_ = NULL; |
| 1874 | |
| 1875 | if (this->is_relro_) |
| 1876 | this->output_section_->set_is_relro(); |
| 1877 | else |
| 1878 | this->output_section_->clear_is_relro(); |
| 1879 | |
| 1880 | return true; |
| 1881 | } |
| 1882 | |
| 1883 | // Get the list of segments to use for an allocated section when using |
| 1884 | // a PHDRS clause. |
| 1885 | |
| 1886 | Output_section* |
| 1887 | Output_section_definition::allocate_to_segment(String_list** phdrs_list, |
| 1888 | bool* orphan) |
| 1889 | { |
| 1890 | if (this->output_section_ == NULL) |
| 1891 | return NULL; |
| 1892 | if ((this->output_section_->flags() & elfcpp::SHF_ALLOC) == 0) |
| 1893 | return NULL; |
| 1894 | *orphan = false; |
| 1895 | if (this->phdrs_ != NULL) |
| 1896 | *phdrs_list = this->phdrs_; |
| 1897 | return this->output_section_; |
| 1898 | } |
| 1899 | |
| 1900 | // Look for an output section by name and return the address, the load |
| 1901 | // address, the alignment, and the size. This is used when an |
| 1902 | // expression refers to an output section which was not actually |
| 1903 | // created. This returns true if the section was found, false |
| 1904 | // otherwise. |
| 1905 | |
| 1906 | bool |
| 1907 | Output_section_definition::get_output_section_info(const char* name, |
| 1908 | uint64_t* address, |
| 1909 | uint64_t* load_address, |
| 1910 | uint64_t* addralign, |
| 1911 | uint64_t* size) const |
| 1912 | { |
| 1913 | if (this->name_ != name) |
| 1914 | return false; |
| 1915 | |
| 1916 | if (this->output_section_ != NULL) |
| 1917 | { |
| 1918 | *address = this->output_section_->address(); |
| 1919 | if (this->output_section_->has_load_address()) |
| 1920 | *load_address = this->output_section_->load_address(); |
| 1921 | else |
| 1922 | *load_address = *address; |
| 1923 | *addralign = this->output_section_->addralign(); |
| 1924 | *size = this->output_section_->current_data_size(); |
| 1925 | } |
| 1926 | else |
| 1927 | { |
| 1928 | *address = this->evaluated_address_; |
| 1929 | *load_address = this->evaluated_load_address_; |
| 1930 | *addralign = this->evaluated_addralign_; |
| 1931 | *size = 0; |
| 1932 | } |
| 1933 | |
| 1934 | return true; |
| 1935 | } |
| 1936 | |
| 1937 | // Print for debugging. |
| 1938 | |
| 1939 | void |
| 1940 | Output_section_definition::print(FILE* f) const |
| 1941 | { |
| 1942 | fprintf(f, " %s ", this->name_.c_str()); |
| 1943 | |
| 1944 | if (this->address_ != NULL) |
| 1945 | { |
| 1946 | this->address_->print(f); |
| 1947 | fprintf(f, " "); |
| 1948 | } |
| 1949 | |
| 1950 | fprintf(f, ": "); |
| 1951 | |
| 1952 | if (this->load_address_ != NULL) |
| 1953 | { |
| 1954 | fprintf(f, "AT("); |
| 1955 | this->load_address_->print(f); |
| 1956 | fprintf(f, ") "); |
| 1957 | } |
| 1958 | |
| 1959 | if (this->align_ != NULL) |
| 1960 | { |
| 1961 | fprintf(f, "ALIGN("); |
| 1962 | this->align_->print(f); |
| 1963 | fprintf(f, ") "); |
| 1964 | } |
| 1965 | |
| 1966 | if (this->subalign_ != NULL) |
| 1967 | { |
| 1968 | fprintf(f, "SUBALIGN("); |
| 1969 | this->subalign_->print(f); |
| 1970 | fprintf(f, ") "); |
| 1971 | } |
| 1972 | |
| 1973 | fprintf(f, "{\n"); |
| 1974 | |
| 1975 | for (Output_section_elements::const_iterator p = this->elements_.begin(); |
| 1976 | p != this->elements_.end(); |
| 1977 | ++p) |
| 1978 | (*p)->print(f); |
| 1979 | |
| 1980 | fprintf(f, " }"); |
| 1981 | |
| 1982 | if (this->fill_ != NULL) |
| 1983 | { |
| 1984 | fprintf(f, " = "); |
| 1985 | this->fill_->print(f); |
| 1986 | } |
| 1987 | |
| 1988 | if (this->phdrs_ != NULL) |
| 1989 | { |
| 1990 | for (String_list::const_iterator p = this->phdrs_->begin(); |
| 1991 | p != this->phdrs_->end(); |
| 1992 | ++p) |
| 1993 | fprintf(f, " :%s", p->c_str()); |
| 1994 | } |
| 1995 | |
| 1996 | fprintf(f, "\n"); |
| 1997 | } |
| 1998 | |
| 1999 | // An output section created to hold orphaned input sections. These |
| 2000 | // do not actually appear in linker scripts. However, for convenience |
| 2001 | // when setting the output section addresses, we put a marker to these |
| 2002 | // sections in the appropriate place in the list of SECTIONS elements. |
| 2003 | |
| 2004 | class Orphan_output_section : public Sections_element |
| 2005 | { |
| 2006 | public: |
| 2007 | Orphan_output_section(Output_section* os) |
| 2008 | : os_(os) |
| 2009 | { } |
| 2010 | |
| 2011 | // Return whether to place an orphan section after this one. |
| 2012 | bool |
| 2013 | place_orphan_here(const Output_section *os, bool* exact, bool*) const; |
| 2014 | |
| 2015 | // Set section addresses. |
| 2016 | void |
| 2017 | set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*); |
| 2018 | |
| 2019 | // Get the list of segments to use for an allocated section when |
| 2020 | // using a PHDRS clause. |
| 2021 | Output_section* |
| 2022 | allocate_to_segment(String_list**, bool*); |
| 2023 | |
| 2024 | // Return the associated Output_section. |
| 2025 | Output_section* |
| 2026 | get_output_section() const |
| 2027 | { return this->os_; } |
| 2028 | |
| 2029 | // Print for debugging. |
| 2030 | void |
| 2031 | print(FILE* f) const |
| 2032 | { |
| 2033 | fprintf(f, " marker for orphaned output section %s\n", |
| 2034 | this->os_->name()); |
| 2035 | } |
| 2036 | |
| 2037 | private: |
| 2038 | Output_section* os_; |
| 2039 | }; |
| 2040 | |
| 2041 | // Whether to place another orphan section after this one. |
| 2042 | |
| 2043 | bool |
| 2044 | Orphan_output_section::place_orphan_here(const Output_section* os, |
| 2045 | bool* exact, |
| 2046 | bool* is_relro) const |
| 2047 | { |
| 2048 | if (this->os_->type() == os->type() |
| 2049 | && this->os_->flags() == os->flags()) |
| 2050 | { |
| 2051 | *exact = true; |
| 2052 | *is_relro = this->os_->is_relro(); |
| 2053 | return true; |
| 2054 | } |
| 2055 | return false; |
| 2056 | } |
| 2057 | |
| 2058 | // Set section addresses. |
| 2059 | |
| 2060 | void |
| 2061 | Orphan_output_section::set_section_addresses(Symbol_table*, Layout*, |
| 2062 | uint64_t* dot_value, |
| 2063 | uint64_t* load_address) |
| 2064 | { |
| 2065 | typedef std::list<std::pair<Relobj*, unsigned int> > Input_section_list; |
| 2066 | |
| 2067 | bool have_load_address = *load_address != *dot_value; |
| 2068 | |
| 2069 | uint64_t address = *dot_value; |
| 2070 | address = align_address(address, this->os_->addralign()); |
| 2071 | |
| 2072 | if ((this->os_->flags() & elfcpp::SHF_ALLOC) != 0) |
| 2073 | { |
| 2074 | this->os_->set_address(address); |
| 2075 | if (have_load_address) |
| 2076 | this->os_->set_load_address(align_address(*load_address, |
| 2077 | this->os_->addralign())); |
| 2078 | } |
| 2079 | |
| 2080 | Input_section_list input_sections; |
| 2081 | address += this->os_->get_input_sections(address, "", &input_sections); |
| 2082 | |
| 2083 | for (Input_section_list::iterator p = input_sections.begin(); |
| 2084 | p != input_sections.end(); |
| 2085 | ++p) |
| 2086 | { |
| 2087 | uint64_t addralign; |
| 2088 | uint64_t size; |
| 2089 | |
| 2090 | // We know what are single-threaded, so it is OK to lock the |
| 2091 | // object. |
| 2092 | { |
| 2093 | const Task* task = reinterpret_cast<const Task*>(-1); |
| 2094 | Task_lock_obj<Object> tl(task, p->first); |
| 2095 | addralign = p->first->section_addralign(p->second); |
| 2096 | size = p->first->section_size(p->second); |
| 2097 | } |
| 2098 | |
| 2099 | address = align_address(address, addralign); |
| 2100 | this->os_->add_input_section_for_script(p->first, p->second, size, |
| 2101 | addralign); |
| 2102 | address += size; |
| 2103 | } |
| 2104 | |
| 2105 | if (!have_load_address) |
| 2106 | *load_address = address; |
| 2107 | else |
| 2108 | *load_address += address - *dot_value; |
| 2109 | |
| 2110 | *dot_value = address; |
| 2111 | } |
| 2112 | |
| 2113 | // Get the list of segments to use for an allocated section when using |
| 2114 | // a PHDRS clause. If this is an allocated section, return the |
| 2115 | // Output_section. We don't change the list of segments. |
| 2116 | |
| 2117 | Output_section* |
| 2118 | Orphan_output_section::allocate_to_segment(String_list**, bool* orphan) |
| 2119 | { |
| 2120 | if ((this->os_->flags() & elfcpp::SHF_ALLOC) == 0) |
| 2121 | return NULL; |
| 2122 | *orphan = true; |
| 2123 | return this->os_; |
| 2124 | } |
| 2125 | |
| 2126 | // Class Phdrs_element. A program header from a PHDRS clause. |
| 2127 | |
| 2128 | class Phdrs_element |
| 2129 | { |
| 2130 | public: |
| 2131 | Phdrs_element(const char* name, size_t namelen, unsigned int type, |
| 2132 | bool includes_filehdr, bool includes_phdrs, |
| 2133 | bool is_flags_valid, unsigned int flags, |
| 2134 | Expression* load_address) |
| 2135 | : name_(name, namelen), type_(type), includes_filehdr_(includes_filehdr), |
| 2136 | includes_phdrs_(includes_phdrs), is_flags_valid_(is_flags_valid), |
| 2137 | flags_(flags), load_address_(load_address), load_address_value_(0), |
| 2138 | segment_(NULL) |
| 2139 | { } |
| 2140 | |
| 2141 | // Return the name of this segment. |
| 2142 | const std::string& |
| 2143 | name() const |
| 2144 | { return this->name_; } |
| 2145 | |
| 2146 | // Return the type of the segment. |
| 2147 | unsigned int |
| 2148 | type() const |
| 2149 | { return this->type_; } |
| 2150 | |
| 2151 | // Whether to include the file header. |
| 2152 | bool |
| 2153 | includes_filehdr() const |
| 2154 | { return this->includes_filehdr_; } |
| 2155 | |
| 2156 | // Whether to include the program headers. |
| 2157 | bool |
| 2158 | includes_phdrs() const |
| 2159 | { return this->includes_phdrs_; } |
| 2160 | |
| 2161 | // Return whether there is a load address. |
| 2162 | bool |
| 2163 | has_load_address() const |
| 2164 | { return this->load_address_ != NULL; } |
| 2165 | |
| 2166 | // Evaluate the load address expression if there is one. |
| 2167 | void |
| 2168 | eval_load_address(Symbol_table* symtab, Layout* layout) |
| 2169 | { |
| 2170 | if (this->load_address_ != NULL) |
| 2171 | this->load_address_value_ = this->load_address_->eval(symtab, layout, |
| 2172 | true); |
| 2173 | } |
| 2174 | |
| 2175 | // Return the load address. |
| 2176 | uint64_t |
| 2177 | load_address() const |
| 2178 | { |
| 2179 | gold_assert(this->load_address_ != NULL); |
| 2180 | return this->load_address_value_; |
| 2181 | } |
| 2182 | |
| 2183 | // Create the segment. |
| 2184 | Output_segment* |
| 2185 | create_segment(Layout* layout) |
| 2186 | { |
| 2187 | this->segment_ = layout->make_output_segment(this->type_, this->flags_); |
| 2188 | return this->segment_; |
| 2189 | } |
| 2190 | |
| 2191 | // Return the segment. |
| 2192 | Output_segment* |
| 2193 | segment() |
| 2194 | { return this->segment_; } |
| 2195 | |
| 2196 | // Set the segment flags if appropriate. |
| 2197 | void |
| 2198 | set_flags_if_valid() |
| 2199 | { |
| 2200 | if (this->is_flags_valid_) |
| 2201 | this->segment_->set_flags(this->flags_); |
| 2202 | } |
| 2203 | |
| 2204 | // Print for debugging. |
| 2205 | void |
| 2206 | print(FILE*) const; |
| 2207 | |
| 2208 | private: |
| 2209 | // The name used in the script. |
| 2210 | std::string name_; |
| 2211 | // The type of the segment (PT_LOAD, etc.). |
| 2212 | unsigned int type_; |
| 2213 | // Whether this segment includes the file header. |
| 2214 | bool includes_filehdr_; |
| 2215 | // Whether this segment includes the section headers. |
| 2216 | bool includes_phdrs_; |
| 2217 | // Whether the flags were explicitly specified. |
| 2218 | bool is_flags_valid_; |
| 2219 | // The flags for this segment (PF_R, etc.) if specified. |
| 2220 | unsigned int flags_; |
| 2221 | // The expression for the load address for this segment. This may |
| 2222 | // be NULL. |
| 2223 | Expression* load_address_; |
| 2224 | // The actual load address from evaluating the expression. |
| 2225 | uint64_t load_address_value_; |
| 2226 | // The segment itself. |
| 2227 | Output_segment* segment_; |
| 2228 | }; |
| 2229 | |
| 2230 | // Print for debugging. |
| 2231 | |
| 2232 | void |
| 2233 | Phdrs_element::print(FILE* f) const |
| 2234 | { |
| 2235 | fprintf(f, " %s 0x%x", this->name_.c_str(), this->type_); |
| 2236 | if (this->includes_filehdr_) |
| 2237 | fprintf(f, " FILEHDR"); |
| 2238 | if (this->includes_phdrs_) |
| 2239 | fprintf(f, " PHDRS"); |
| 2240 | if (this->is_flags_valid_) |
| 2241 | fprintf(f, " FLAGS(%u)", this->flags_); |
| 2242 | if (this->load_address_ != NULL) |
| 2243 | { |
| 2244 | fprintf(f, " AT("); |
| 2245 | this->load_address_->print(f); |
| 2246 | fprintf(f, ")"); |
| 2247 | } |
| 2248 | fprintf(f, ";\n"); |
| 2249 | } |
| 2250 | |
| 2251 | // Class Script_sections. |
| 2252 | |
| 2253 | Script_sections::Script_sections() |
| 2254 | : saw_sections_clause_(false), |
| 2255 | in_sections_clause_(false), |
| 2256 | sections_elements_(NULL), |
| 2257 | output_section_(NULL), |
| 2258 | phdrs_elements_(NULL), |
| 2259 | data_segment_align_index_(-1U), |
| 2260 | saw_relro_end_(false) |
| 2261 | { |
| 2262 | } |
| 2263 | |
| 2264 | // Start a SECTIONS clause. |
| 2265 | |
| 2266 | void |
| 2267 | Script_sections::start_sections() |
| 2268 | { |
| 2269 | gold_assert(!this->in_sections_clause_ && this->output_section_ == NULL); |
| 2270 | this->saw_sections_clause_ = true; |
| 2271 | this->in_sections_clause_ = true; |
| 2272 | if (this->sections_elements_ == NULL) |
| 2273 | this->sections_elements_ = new Sections_elements; |
| 2274 | } |
| 2275 | |
| 2276 | // Finish a SECTIONS clause. |
| 2277 | |
| 2278 | void |
| 2279 | Script_sections::finish_sections() |
| 2280 | { |
| 2281 | gold_assert(this->in_sections_clause_ && this->output_section_ == NULL); |
| 2282 | this->in_sections_clause_ = false; |
| 2283 | } |
| 2284 | |
| 2285 | // Add a symbol to be defined. |
| 2286 | |
| 2287 | void |
| 2288 | Script_sections::add_symbol_assignment(const char* name, size_t length, |
| 2289 | Expression* val, bool provide, |
| 2290 | bool hidden) |
| 2291 | { |
| 2292 | if (this->output_section_ != NULL) |
| 2293 | this->output_section_->add_symbol_assignment(name, length, val, |
| 2294 | provide, hidden); |
| 2295 | else |
| 2296 | { |
| 2297 | Sections_element* p = new Sections_element_assignment(name, length, |
| 2298 | val, provide, |
| 2299 | hidden); |
| 2300 | this->sections_elements_->push_back(p); |
| 2301 | } |
| 2302 | } |
| 2303 | |
| 2304 | // Add an assignment to the special dot symbol. |
| 2305 | |
| 2306 | void |
| 2307 | Script_sections::add_dot_assignment(Expression* val) |
| 2308 | { |
| 2309 | if (this->output_section_ != NULL) |
| 2310 | this->output_section_->add_dot_assignment(val); |
| 2311 | else |
| 2312 | { |
| 2313 | Sections_element* p = new Sections_element_dot_assignment(val); |
| 2314 | this->sections_elements_->push_back(p); |
| 2315 | } |
| 2316 | } |
| 2317 | |
| 2318 | // Add an assertion. |
| 2319 | |
| 2320 | void |
| 2321 | Script_sections::add_assertion(Expression* check, const char* message, |
| 2322 | size_t messagelen) |
| 2323 | { |
| 2324 | if (this->output_section_ != NULL) |
| 2325 | this->output_section_->add_assertion(check, message, messagelen); |
| 2326 | else |
| 2327 | { |
| 2328 | Sections_element* p = new Sections_element_assertion(check, message, |
| 2329 | messagelen); |
| 2330 | this->sections_elements_->push_back(p); |
| 2331 | } |
| 2332 | } |
| 2333 | |
| 2334 | // Start processing entries for an output section. |
| 2335 | |
| 2336 | void |
| 2337 | Script_sections::start_output_section( |
| 2338 | const char* name, |
| 2339 | size_t namelen, |
| 2340 | const Parser_output_section_header *header) |
| 2341 | { |
| 2342 | Output_section_definition* posd = new Output_section_definition(name, |
| 2343 | namelen, |
| 2344 | header); |
| 2345 | this->sections_elements_->push_back(posd); |
| 2346 | gold_assert(this->output_section_ == NULL); |
| 2347 | this->output_section_ = posd; |
| 2348 | } |
| 2349 | |
| 2350 | // Stop processing entries for an output section. |
| 2351 | |
| 2352 | void |
| 2353 | Script_sections::finish_output_section( |
| 2354 | const Parser_output_section_trailer* trailer) |
| 2355 | { |
| 2356 | gold_assert(this->output_section_ != NULL); |
| 2357 | this->output_section_->finish(trailer); |
| 2358 | this->output_section_ = NULL; |
| 2359 | } |
| 2360 | |
| 2361 | // Add a data item to the current output section. |
| 2362 | |
| 2363 | void |
| 2364 | Script_sections::add_data(int size, bool is_signed, Expression* val) |
| 2365 | { |
| 2366 | gold_assert(this->output_section_ != NULL); |
| 2367 | this->output_section_->add_data(size, is_signed, val); |
| 2368 | } |
| 2369 | |
| 2370 | // Add a fill value setting to the current output section. |
| 2371 | |
| 2372 | void |
| 2373 | Script_sections::add_fill(Expression* val) |
| 2374 | { |
| 2375 | gold_assert(this->output_section_ != NULL); |
| 2376 | this->output_section_->add_fill(val); |
| 2377 | } |
| 2378 | |
| 2379 | // Add an input section specification to the current output section. |
| 2380 | |
| 2381 | void |
| 2382 | Script_sections::add_input_section(const Input_section_spec* spec, bool keep) |
| 2383 | { |
| 2384 | gold_assert(this->output_section_ != NULL); |
| 2385 | this->output_section_->add_input_section(spec, keep); |
| 2386 | } |
| 2387 | |
| 2388 | // This is called when we see DATA_SEGMENT_ALIGN. It means that any |
| 2389 | // subsequent output sections may be relro. |
| 2390 | |
| 2391 | void |
| 2392 | Script_sections::data_segment_align() |
| 2393 | { |
| 2394 | if (this->data_segment_align_index_ != -1U) |
| 2395 | gold_error(_("DATA_SEGMENT_ALIGN may only appear once in a linker script")); |
| 2396 | this->data_segment_align_index_ = this->sections_elements_->size(); |
| 2397 | } |
| 2398 | |
| 2399 | // This is called when we see DATA_SEGMENT_RELRO_END. It means that |
| 2400 | // any output sections seen since DATA_SEGMENT_ALIGN are relro. |
| 2401 | |
| 2402 | void |
| 2403 | Script_sections::data_segment_relro_end() |
| 2404 | { |
| 2405 | if (this->saw_relro_end_) |
| 2406 | gold_error(_("DATA_SEGMENT_RELRO_END may only appear once " |
| 2407 | "in a linker script")); |
| 2408 | this->saw_relro_end_ = true; |
| 2409 | |
| 2410 | if (this->data_segment_align_index_ == -1U) |
| 2411 | gold_error(_("DATA_SEGMENT_RELRO_END must follow DATA_SEGMENT_ALIGN")); |
| 2412 | else |
| 2413 | { |
| 2414 | for (size_t i = this->data_segment_align_index_; |
| 2415 | i < this->sections_elements_->size(); |
| 2416 | ++i) |
| 2417 | (*this->sections_elements_)[i]->set_is_relro(); |
| 2418 | } |
| 2419 | } |
| 2420 | |
| 2421 | // Create any required sections. |
| 2422 | |
| 2423 | void |
| 2424 | Script_sections::create_sections(Layout* layout) |
| 2425 | { |
| 2426 | if (!this->saw_sections_clause_) |
| 2427 | return; |
| 2428 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2429 | p != this->sections_elements_->end(); |
| 2430 | ++p) |
| 2431 | (*p)->create_sections(layout); |
| 2432 | } |
| 2433 | |
| 2434 | // Add any symbols we are defining to the symbol table. |
| 2435 | |
| 2436 | void |
| 2437 | Script_sections::add_symbols_to_table(Symbol_table* symtab) |
| 2438 | { |
| 2439 | if (!this->saw_sections_clause_) |
| 2440 | return; |
| 2441 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2442 | p != this->sections_elements_->end(); |
| 2443 | ++p) |
| 2444 | (*p)->add_symbols_to_table(symtab); |
| 2445 | } |
| 2446 | |
| 2447 | // Finalize symbols and check assertions. |
| 2448 | |
| 2449 | void |
| 2450 | Script_sections::finalize_symbols(Symbol_table* symtab, const Layout* layout) |
| 2451 | { |
| 2452 | if (!this->saw_sections_clause_) |
| 2453 | return; |
| 2454 | uint64_t dot_value = 0; |
| 2455 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2456 | p != this->sections_elements_->end(); |
| 2457 | ++p) |
| 2458 | (*p)->finalize_symbols(symtab, layout, &dot_value); |
| 2459 | } |
| 2460 | |
| 2461 | // Return the name of the output section to use for an input file name |
| 2462 | // and section name. |
| 2463 | |
| 2464 | const char* |
| 2465 | Script_sections::output_section_name(const char* file_name, |
| 2466 | const char* section_name, |
| 2467 | Output_section*** output_section_slot) |
| 2468 | { |
| 2469 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 2470 | p != this->sections_elements_->end(); |
| 2471 | ++p) |
| 2472 | { |
| 2473 | const char* ret = (*p)->output_section_name(file_name, section_name, |
| 2474 | output_section_slot); |
| 2475 | |
| 2476 | if (ret != NULL) |
| 2477 | { |
| 2478 | // The special name /DISCARD/ means that the input section |
| 2479 | // should be discarded. |
| 2480 | if (strcmp(ret, "/DISCARD/") == 0) |
| 2481 | { |
| 2482 | *output_section_slot = NULL; |
| 2483 | return NULL; |
| 2484 | } |
| 2485 | return ret; |
| 2486 | } |
| 2487 | } |
| 2488 | |
| 2489 | // If we couldn't find a mapping for the name, the output section |
| 2490 | // gets the name of the input section. |
| 2491 | |
| 2492 | *output_section_slot = NULL; |
| 2493 | |
| 2494 | return section_name; |
| 2495 | } |
| 2496 | |
| 2497 | // Place a marker for an orphan output section into the SECTIONS |
| 2498 | // clause. |
| 2499 | |
| 2500 | void |
| 2501 | Script_sections::place_orphan(Output_section* os) |
| 2502 | { |
| 2503 | // Look for an output section definition which matches the output |
| 2504 | // section. Put a marker after that section. |
| 2505 | bool is_relro = false; |
| 2506 | Sections_elements::iterator place = this->sections_elements_->end(); |
| 2507 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2508 | p != this->sections_elements_->end(); |
| 2509 | ++p) |
| 2510 | { |
| 2511 | bool exact = false; |
| 2512 | bool is_relro_here; |
| 2513 | if ((*p)->place_orphan_here(os, &exact, &is_relro_here)) |
| 2514 | { |
| 2515 | place = p; |
| 2516 | is_relro = is_relro_here; |
| 2517 | if (exact) |
| 2518 | break; |
| 2519 | } |
| 2520 | } |
| 2521 | |
| 2522 | // The insert function puts the new element before the iterator. |
| 2523 | if (place != this->sections_elements_->end()) |
| 2524 | ++place; |
| 2525 | |
| 2526 | this->sections_elements_->insert(place, new Orphan_output_section(os)); |
| 2527 | |
| 2528 | if (is_relro) |
| 2529 | os->set_is_relro(); |
| 2530 | else |
| 2531 | os->clear_is_relro(); |
| 2532 | } |
| 2533 | |
| 2534 | // Set the addresses of all the output sections. Walk through all the |
| 2535 | // elements, tracking the dot symbol. Apply assignments which set |
| 2536 | // absolute symbol values, in case they are used when setting dot. |
| 2537 | // Fill in data statement values. As we find output sections, set the |
| 2538 | // address, set the address of all associated input sections, and |
| 2539 | // update dot. Return the segment which should hold the file header |
| 2540 | // and segment headers, if any. |
| 2541 | |
| 2542 | Output_segment* |
| 2543 | Script_sections::set_section_addresses(Symbol_table* symtab, Layout* layout) |
| 2544 | { |
| 2545 | gold_assert(this->saw_sections_clause_); |
| 2546 | |
| 2547 | // Implement ONLY_IF_RO/ONLY_IF_RW constraints. These are a pain |
| 2548 | // for our representation. |
| 2549 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2550 | p != this->sections_elements_->end(); |
| 2551 | ++p) |
| 2552 | { |
| 2553 | Output_section_definition* posd; |
| 2554 | Section_constraint failed_constraint = (*p)->check_constraint(&posd); |
| 2555 | if (failed_constraint != CONSTRAINT_NONE) |
| 2556 | { |
| 2557 | Sections_elements::iterator q; |
| 2558 | for (q = this->sections_elements_->begin(); |
| 2559 | q != this->sections_elements_->end(); |
| 2560 | ++q) |
| 2561 | { |
| 2562 | if (q != p) |
| 2563 | { |
| 2564 | if ((*q)->alternate_constraint(posd, failed_constraint)) |
| 2565 | break; |
| 2566 | } |
| 2567 | } |
| 2568 | |
| 2569 | if (q == this->sections_elements_->end()) |
| 2570 | gold_error(_("no matching section constraint")); |
| 2571 | } |
| 2572 | } |
| 2573 | |
| 2574 | // Force the alignment of the first TLS section to be the maximum |
| 2575 | // alignment of all TLS sections. |
| 2576 | Output_section* first_tls = NULL; |
| 2577 | uint64_t tls_align = 0; |
| 2578 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 2579 | p != this->sections_elements_->end(); |
| 2580 | ++p) |
| 2581 | { |
| 2582 | Output_section *os = (*p)->get_output_section(); |
| 2583 | if (os != NULL && (os->flags() & elfcpp::SHF_TLS) != 0) |
| 2584 | { |
| 2585 | if (first_tls == NULL) |
| 2586 | first_tls = os; |
| 2587 | if (os->addralign() > tls_align) |
| 2588 | tls_align = os->addralign(); |
| 2589 | } |
| 2590 | } |
| 2591 | if (first_tls != NULL) |
| 2592 | first_tls->set_addralign(tls_align); |
| 2593 | |
| 2594 | // For a relocatable link, we implicitly set dot to zero. |
| 2595 | uint64_t dot_value = 0; |
| 2596 | uint64_t load_address = 0; |
| 2597 | for (Sections_elements::iterator p = this->sections_elements_->begin(); |
| 2598 | p != this->sections_elements_->end(); |
| 2599 | ++p) |
| 2600 | (*p)->set_section_addresses(symtab, layout, &dot_value, &load_address); |
| 2601 | |
| 2602 | if (this->phdrs_elements_ != NULL) |
| 2603 | { |
| 2604 | for (Phdrs_elements::iterator p = this->phdrs_elements_->begin(); |
| 2605 | p != this->phdrs_elements_->end(); |
| 2606 | ++p) |
| 2607 | (*p)->eval_load_address(symtab, layout); |
| 2608 | } |
| 2609 | |
| 2610 | return this->create_segments(layout); |
| 2611 | } |
| 2612 | |
| 2613 | // Sort the sections in order to put them into segments. |
| 2614 | |
| 2615 | class Sort_output_sections |
| 2616 | { |
| 2617 | public: |
| 2618 | bool |
| 2619 | operator()(const Output_section* os1, const Output_section* os2) const; |
| 2620 | }; |
| 2621 | |
| 2622 | bool |
| 2623 | Sort_output_sections::operator()(const Output_section* os1, |
| 2624 | const Output_section* os2) const |
| 2625 | { |
| 2626 | // Sort first by the load address. |
| 2627 | uint64_t lma1 = (os1->has_load_address() |
| 2628 | ? os1->load_address() |
| 2629 | : os1->address()); |
| 2630 | uint64_t lma2 = (os2->has_load_address() |
| 2631 | ? os2->load_address() |
| 2632 | : os2->address()); |
| 2633 | if (lma1 != lma2) |
| 2634 | return lma1 < lma2; |
| 2635 | |
| 2636 | // Then sort by the virtual address. |
| 2637 | if (os1->address() != os2->address()) |
| 2638 | return os1->address() < os2->address(); |
| 2639 | |
| 2640 | // Sort TLS sections to the end. |
| 2641 | bool tls1 = (os1->flags() & elfcpp::SHF_TLS) != 0; |
| 2642 | bool tls2 = (os2->flags() & elfcpp::SHF_TLS) != 0; |
| 2643 | if (tls1 != tls2) |
| 2644 | return tls2; |
| 2645 | |
| 2646 | // Sort PROGBITS before NOBITS. |
| 2647 | if (os1->type() == elfcpp::SHT_PROGBITS && os2->type() == elfcpp::SHT_NOBITS) |
| 2648 | return true; |
| 2649 | if (os1->type() == elfcpp::SHT_NOBITS && os2->type() == elfcpp::SHT_PROGBITS) |
| 2650 | return false; |
| 2651 | |
| 2652 | // Otherwise we don't care. |
| 2653 | return false; |
| 2654 | } |
| 2655 | |
| 2656 | // Return whether OS is a BSS section. This is a SHT_NOBITS section. |
| 2657 | // We treat a section with the SHF_TLS flag set as taking up space |
| 2658 | // even if it is SHT_NOBITS (this is true of .tbss), as we allocate |
| 2659 | // space for them in the file. |
| 2660 | |
| 2661 | bool |
| 2662 | Script_sections::is_bss_section(const Output_section* os) |
| 2663 | { |
| 2664 | return (os->type() == elfcpp::SHT_NOBITS |
| 2665 | && (os->flags() & elfcpp::SHF_TLS) == 0); |
| 2666 | } |
| 2667 | |
| 2668 | // Return the size taken by the file header and the program headers. |
| 2669 | |
| 2670 | size_t |
| 2671 | Script_sections::total_header_size(Layout* layout) const |
| 2672 | { |
| 2673 | size_t segment_count = layout->segment_count(); |
| 2674 | size_t file_header_size; |
| 2675 | size_t segment_headers_size; |
| 2676 | if (parameters->target().get_size() == 32) |
| 2677 | { |
| 2678 | file_header_size = elfcpp::Elf_sizes<32>::ehdr_size; |
| 2679 | segment_headers_size = segment_count * elfcpp::Elf_sizes<32>::phdr_size; |
| 2680 | } |
| 2681 | else if (parameters->target().get_size() == 64) |
| 2682 | { |
| 2683 | file_header_size = elfcpp::Elf_sizes<64>::ehdr_size; |
| 2684 | segment_headers_size = segment_count * elfcpp::Elf_sizes<64>::phdr_size; |
| 2685 | } |
| 2686 | else |
| 2687 | gold_unreachable(); |
| 2688 | |
| 2689 | return file_header_size + segment_headers_size; |
| 2690 | } |
| 2691 | |
| 2692 | // Return the amount we have to subtract from the LMA to accomodate |
| 2693 | // headers of the given size. The complication is that the file |
| 2694 | // header have to be at the start of a page, as otherwise it will not |
| 2695 | // be at the start of the file. |
| 2696 | |
| 2697 | uint64_t |
| 2698 | Script_sections::header_size_adjustment(uint64_t lma, |
| 2699 | size_t sizeof_headers) const |
| 2700 | { |
| 2701 | const uint64_t abi_pagesize = parameters->target().abi_pagesize(); |
| 2702 | uint64_t hdr_lma = lma - sizeof_headers; |
| 2703 | hdr_lma &= ~(abi_pagesize - 1); |
| 2704 | return lma - hdr_lma; |
| 2705 | } |
| 2706 | |
| 2707 | // Create the PT_LOAD segments when using a SECTIONS clause. Returns |
| 2708 | // the segment which should hold the file header and segment headers, |
| 2709 | // if any. |
| 2710 | |
| 2711 | Output_segment* |
| 2712 | Script_sections::create_segments(Layout* layout) |
| 2713 | { |
| 2714 | gold_assert(this->saw_sections_clause_); |
| 2715 | |
| 2716 | if (parameters->options().relocatable()) |
| 2717 | return NULL; |
| 2718 | |
| 2719 | if (this->saw_phdrs_clause()) |
| 2720 | return create_segments_from_phdrs_clause(layout); |
| 2721 | |
| 2722 | Layout::Section_list sections; |
| 2723 | layout->get_allocated_sections(§ions); |
| 2724 | |
| 2725 | // Sort the sections by address. |
| 2726 | std::stable_sort(sections.begin(), sections.end(), Sort_output_sections()); |
| 2727 | |
| 2728 | this->create_note_and_tls_segments(layout, §ions); |
| 2729 | |
| 2730 | // Walk through the sections adding them to PT_LOAD segments. |
| 2731 | const uint64_t abi_pagesize = parameters->target().abi_pagesize(); |
| 2732 | Output_segment* first_seg = NULL; |
| 2733 | Output_segment* current_seg = NULL; |
| 2734 | bool is_current_seg_readonly = true; |
| 2735 | Layout::Section_list::iterator plast = sections.end(); |
| 2736 | uint64_t last_vma = 0; |
| 2737 | uint64_t last_lma = 0; |
| 2738 | uint64_t last_size = 0; |
| 2739 | for (Layout::Section_list::iterator p = sections.begin(); |
| 2740 | p != sections.end(); |
| 2741 | ++p) |
| 2742 | { |
| 2743 | const uint64_t vma = (*p)->address(); |
| 2744 | const uint64_t lma = ((*p)->has_load_address() |
| 2745 | ? (*p)->load_address() |
| 2746 | : vma); |
| 2747 | const uint64_t size = (*p)->current_data_size(); |
| 2748 | |
| 2749 | bool need_new_segment; |
| 2750 | if (current_seg == NULL) |
| 2751 | need_new_segment = true; |
| 2752 | else if (lma - vma != last_lma - last_vma) |
| 2753 | { |
| 2754 | // This section has a different LMA relationship than the |
| 2755 | // last one; we need a new segment. |
| 2756 | need_new_segment = true; |
| 2757 | } |
| 2758 | else if (align_address(last_lma + last_size, abi_pagesize) |
| 2759 | < align_address(lma, abi_pagesize)) |
| 2760 | { |
| 2761 | // Putting this section in the segment would require |
| 2762 | // skipping a page. |
| 2763 | need_new_segment = true; |
| 2764 | } |
| 2765 | else if (is_bss_section(*plast) && !is_bss_section(*p)) |
| 2766 | { |
| 2767 | // A non-BSS section can not follow a BSS section in the |
| 2768 | // same segment. |
| 2769 | need_new_segment = true; |
| 2770 | } |
| 2771 | else if (is_current_seg_readonly |
| 2772 | && ((*p)->flags() & elfcpp::SHF_WRITE) != 0 |
| 2773 | && !parameters->options().omagic()) |
| 2774 | { |
| 2775 | // Don't put a writable section in the same segment as a |
| 2776 | // non-writable section. |
| 2777 | need_new_segment = true; |
| 2778 | } |
| 2779 | else |
| 2780 | { |
| 2781 | // Otherwise, reuse the existing segment. |
| 2782 | need_new_segment = false; |
| 2783 | } |
| 2784 | |
| 2785 | elfcpp::Elf_Word seg_flags = |
| 2786 | Layout::section_flags_to_segment((*p)->flags()); |
| 2787 | |
| 2788 | if (need_new_segment) |
| 2789 | { |
| 2790 | current_seg = layout->make_output_segment(elfcpp::PT_LOAD, |
| 2791 | seg_flags); |
| 2792 | current_seg->set_addresses(vma, lma); |
| 2793 | if (first_seg == NULL) |
| 2794 | first_seg = current_seg; |
| 2795 | is_current_seg_readonly = true; |
| 2796 | } |
| 2797 | |
| 2798 | current_seg->add_output_section(*p, seg_flags); |
| 2799 | |
| 2800 | if (((*p)->flags() & elfcpp::SHF_WRITE) != 0) |
| 2801 | is_current_seg_readonly = false; |
| 2802 | |
| 2803 | plast = p; |
| 2804 | last_vma = vma; |
| 2805 | last_lma = lma; |
| 2806 | last_size = size; |
| 2807 | } |
| 2808 | |
| 2809 | // An ELF program should work even if the program headers are not in |
| 2810 | // a PT_LOAD segment. However, it appears that the Linux kernel |
| 2811 | // does not set the AT_PHDR auxiliary entry in that case. It sets |
| 2812 | // the load address to p_vaddr - p_offset of the first PT_LOAD |
| 2813 | // segment. It then sets AT_PHDR to the load address plus the |
| 2814 | // offset to the program headers, e_phoff in the file header. This |
| 2815 | // fails when the program headers appear in the file before the |
| 2816 | // first PT_LOAD segment. Therefore, we always create a PT_LOAD |
| 2817 | // segment to hold the file header and the program headers. This is |
| 2818 | // effectively what the GNU linker does, and it is slightly more |
| 2819 | // efficient in any case. We try to use the first PT_LOAD segment |
| 2820 | // if we can, otherwise we make a new one. |
| 2821 | |
| 2822 | if (first_seg == NULL) |
| 2823 | return NULL; |
| 2824 | |
| 2825 | size_t sizeof_headers = this->total_header_size(layout); |
| 2826 | |
| 2827 | uint64_t vma = first_seg->vaddr(); |
| 2828 | uint64_t lma = first_seg->paddr(); |
| 2829 | |
| 2830 | uint64_t subtract = this->header_size_adjustment(lma, sizeof_headers); |
| 2831 | |
| 2832 | if ((lma & (abi_pagesize - 1)) >= sizeof_headers) |
| 2833 | { |
| 2834 | first_seg->set_addresses(vma - subtract, lma - subtract); |
| 2835 | return first_seg; |
| 2836 | } |
| 2837 | |
| 2838 | // If there is no room to squeeze in the headers, then punt. The |
| 2839 | // resulting executable probably won't run on GNU/Linux, but we |
| 2840 | // trust that the user knows what they are doing. |
| 2841 | if (lma < subtract || vma < subtract) |
| 2842 | return NULL; |
| 2843 | |
| 2844 | Output_segment* load_seg = layout->make_output_segment(elfcpp::PT_LOAD, |
| 2845 | elfcpp::PF_R); |
| 2846 | load_seg->set_addresses(vma - subtract, lma - subtract); |
| 2847 | |
| 2848 | return load_seg; |
| 2849 | } |
| 2850 | |
| 2851 | // Create a PT_NOTE segment for each SHT_NOTE section and a PT_TLS |
| 2852 | // segment if there are any SHT_TLS sections. |
| 2853 | |
| 2854 | void |
| 2855 | Script_sections::create_note_and_tls_segments( |
| 2856 | Layout* layout, |
| 2857 | const Layout::Section_list* sections) |
| 2858 | { |
| 2859 | gold_assert(!this->saw_phdrs_clause()); |
| 2860 | |
| 2861 | bool saw_tls = false; |
| 2862 | for (Layout::Section_list::const_iterator p = sections->begin(); |
| 2863 | p != sections->end(); |
| 2864 | ++p) |
| 2865 | { |
| 2866 | if ((*p)->type() == elfcpp::SHT_NOTE) |
| 2867 | { |
| 2868 | elfcpp::Elf_Word seg_flags = |
| 2869 | Layout::section_flags_to_segment((*p)->flags()); |
| 2870 | Output_segment* oseg = layout->make_output_segment(elfcpp::PT_NOTE, |
| 2871 | seg_flags); |
| 2872 | oseg->add_output_section(*p, seg_flags); |
| 2873 | |
| 2874 | // Incorporate any subsequent SHT_NOTE sections, in the |
| 2875 | // hopes that the script is sensible. |
| 2876 | Layout::Section_list::const_iterator pnext = p + 1; |
| 2877 | while (pnext != sections->end() |
| 2878 | && (*pnext)->type() == elfcpp::SHT_NOTE) |
| 2879 | { |
| 2880 | seg_flags = Layout::section_flags_to_segment((*pnext)->flags()); |
| 2881 | oseg->add_output_section(*pnext, seg_flags); |
| 2882 | p = pnext; |
| 2883 | ++pnext; |
| 2884 | } |
| 2885 | } |
| 2886 | |
| 2887 | if (((*p)->flags() & elfcpp::SHF_TLS) != 0) |
| 2888 | { |
| 2889 | if (saw_tls) |
| 2890 | gold_error(_("TLS sections are not adjacent")); |
| 2891 | |
| 2892 | elfcpp::Elf_Word seg_flags = |
| 2893 | Layout::section_flags_to_segment((*p)->flags()); |
| 2894 | Output_segment* oseg = layout->make_output_segment(elfcpp::PT_TLS, |
| 2895 | seg_flags); |
| 2896 | oseg->add_output_section(*p, seg_flags); |
| 2897 | |
| 2898 | Layout::Section_list::const_iterator pnext = p + 1; |
| 2899 | while (pnext != sections->end() |
| 2900 | && ((*pnext)->flags() & elfcpp::SHF_TLS) != 0) |
| 2901 | { |
| 2902 | seg_flags = Layout::section_flags_to_segment((*pnext)->flags()); |
| 2903 | oseg->add_output_section(*pnext, seg_flags); |
| 2904 | p = pnext; |
| 2905 | ++pnext; |
| 2906 | } |
| 2907 | |
| 2908 | saw_tls = true; |
| 2909 | } |
| 2910 | } |
| 2911 | } |
| 2912 | |
| 2913 | // Add a program header. The PHDRS clause is syntactically distinct |
| 2914 | // from the SECTIONS clause, but we implement it with the SECTIONS |
| 2915 | // support becauase PHDRS is useless if there is no SECTIONS clause. |
| 2916 | |
| 2917 | void |
| 2918 | Script_sections::add_phdr(const char* name, size_t namelen, unsigned int type, |
| 2919 | bool includes_filehdr, bool includes_phdrs, |
| 2920 | bool is_flags_valid, unsigned int flags, |
| 2921 | Expression* load_address) |
| 2922 | { |
| 2923 | if (this->phdrs_elements_ == NULL) |
| 2924 | this->phdrs_elements_ = new Phdrs_elements(); |
| 2925 | this->phdrs_elements_->push_back(new Phdrs_element(name, namelen, type, |
| 2926 | includes_filehdr, |
| 2927 | includes_phdrs, |
| 2928 | is_flags_valid, flags, |
| 2929 | load_address)); |
| 2930 | } |
| 2931 | |
| 2932 | // Return the number of segments we expect to create based on the |
| 2933 | // SECTIONS clause. This is used to implement SIZEOF_HEADERS. |
| 2934 | |
| 2935 | size_t |
| 2936 | Script_sections::expected_segment_count(const Layout* layout) const |
| 2937 | { |
| 2938 | if (this->saw_phdrs_clause()) |
| 2939 | return this->phdrs_elements_->size(); |
| 2940 | |
| 2941 | Layout::Section_list sections; |
| 2942 | layout->get_allocated_sections(§ions); |
| 2943 | |
| 2944 | // We assume that we will need two PT_LOAD segments. |
| 2945 | size_t ret = 2; |
| 2946 | |
| 2947 | bool saw_note = false; |
| 2948 | bool saw_tls = false; |
| 2949 | for (Layout::Section_list::const_iterator p = sections.begin(); |
| 2950 | p != sections.end(); |
| 2951 | ++p) |
| 2952 | { |
| 2953 | if ((*p)->type() == elfcpp::SHT_NOTE) |
| 2954 | { |
| 2955 | // Assume that all note sections will fit into a single |
| 2956 | // PT_NOTE segment. |
| 2957 | if (!saw_note) |
| 2958 | { |
| 2959 | ++ret; |
| 2960 | saw_note = true; |
| 2961 | } |
| 2962 | } |
| 2963 | else if (((*p)->flags() & elfcpp::SHF_TLS) != 0) |
| 2964 | { |
| 2965 | // There can only be one PT_TLS segment. |
| 2966 | if (!saw_tls) |
| 2967 | { |
| 2968 | ++ret; |
| 2969 | saw_tls = true; |
| 2970 | } |
| 2971 | } |
| 2972 | } |
| 2973 | |
| 2974 | return ret; |
| 2975 | } |
| 2976 | |
| 2977 | // Create the segments from a PHDRS clause. Return the segment which |
| 2978 | // should hold the file header and program headers, if any. |
| 2979 | |
| 2980 | Output_segment* |
| 2981 | Script_sections::create_segments_from_phdrs_clause(Layout* layout) |
| 2982 | { |
| 2983 | this->attach_sections_using_phdrs_clause(layout); |
| 2984 | return this->set_phdrs_clause_addresses(layout); |
| 2985 | } |
| 2986 | |
| 2987 | // Create the segments from the PHDRS clause, and put the output |
| 2988 | // sections in them. |
| 2989 | |
| 2990 | void |
| 2991 | Script_sections::attach_sections_using_phdrs_clause(Layout* layout) |
| 2992 | { |
| 2993 | typedef std::map<std::string, Output_segment*> Name_to_segment; |
| 2994 | Name_to_segment name_to_segment; |
| 2995 | for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| 2996 | p != this->phdrs_elements_->end(); |
| 2997 | ++p) |
| 2998 | name_to_segment[(*p)->name()] = (*p)->create_segment(layout); |
| 2999 | |
| 3000 | // Walk through the output sections and attach them to segments. |
| 3001 | // Output sections in the script which do not list segments are |
| 3002 | // attached to the same set of segments as the immediately preceding |
| 3003 | // output section. |
| 3004 | String_list* phdr_names = NULL; |
| 3005 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 3006 | p != this->sections_elements_->end(); |
| 3007 | ++p) |
| 3008 | { |
| 3009 | bool orphan; |
| 3010 | Output_section* os = (*p)->allocate_to_segment(&phdr_names, &orphan); |
| 3011 | if (os == NULL) |
| 3012 | continue; |
| 3013 | |
| 3014 | if (phdr_names == NULL) |
| 3015 | { |
| 3016 | gold_error(_("allocated section not in any segment")); |
| 3017 | continue; |
| 3018 | } |
| 3019 | |
| 3020 | // If this is an orphan section--one that was not explicitly |
| 3021 | // mentioned in the linker script--then it should not inherit |
| 3022 | // any segment type other than PT_LOAD. Otherwise, e.g., the |
| 3023 | // PT_INTERP segment will pick up following orphan sections, |
| 3024 | // which does not make sense. If this is not an orphan section, |
| 3025 | // we trust the linker script. |
| 3026 | if (orphan) |
| 3027 | { |
| 3028 | String_list::iterator q = phdr_names->begin(); |
| 3029 | while (q != phdr_names->end()) |
| 3030 | { |
| 3031 | Name_to_segment::const_iterator r = name_to_segment.find(*q); |
| 3032 | // We give errors about unknown segments below. |
| 3033 | if (r == name_to_segment.end() |
| 3034 | || r->second->type() == elfcpp::PT_LOAD) |
| 3035 | ++q; |
| 3036 | else |
| 3037 | q = phdr_names->erase(q); |
| 3038 | } |
| 3039 | } |
| 3040 | |
| 3041 | bool in_load_segment = false; |
| 3042 | for (String_list::const_iterator q = phdr_names->begin(); |
| 3043 | q != phdr_names->end(); |
| 3044 | ++q) |
| 3045 | { |
| 3046 | Name_to_segment::const_iterator r = name_to_segment.find(*q); |
| 3047 | if (r == name_to_segment.end()) |
| 3048 | gold_error(_("no segment %s"), q->c_str()); |
| 3049 | else |
| 3050 | { |
| 3051 | elfcpp::Elf_Word seg_flags = |
| 3052 | Layout::section_flags_to_segment(os->flags()); |
| 3053 | r->second->add_output_section(os, seg_flags); |
| 3054 | |
| 3055 | if (r->second->type() == elfcpp::PT_LOAD) |
| 3056 | { |
| 3057 | if (in_load_segment) |
| 3058 | gold_error(_("section in two PT_LOAD segments")); |
| 3059 | in_load_segment = true; |
| 3060 | } |
| 3061 | } |
| 3062 | } |
| 3063 | |
| 3064 | if (!in_load_segment) |
| 3065 | gold_error(_("allocated section not in any PT_LOAD segment")); |
| 3066 | } |
| 3067 | } |
| 3068 | |
| 3069 | // Set the addresses for segments created from a PHDRS clause. Return |
| 3070 | // the segment which should hold the file header and program headers, |
| 3071 | // if any. |
| 3072 | |
| 3073 | Output_segment* |
| 3074 | Script_sections::set_phdrs_clause_addresses(Layout* layout) |
| 3075 | { |
| 3076 | Output_segment* load_seg = NULL; |
| 3077 | for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| 3078 | p != this->phdrs_elements_->end(); |
| 3079 | ++p) |
| 3080 | { |
| 3081 | // Note that we have to set the flags after adding the output |
| 3082 | // sections to the segment, as adding an output segment can |
| 3083 | // change the flags. |
| 3084 | (*p)->set_flags_if_valid(); |
| 3085 | |
| 3086 | Output_segment* oseg = (*p)->segment(); |
| 3087 | |
| 3088 | if (oseg->type() != elfcpp::PT_LOAD) |
| 3089 | { |
| 3090 | // The addresses of non-PT_LOAD segments are set from the |
| 3091 | // PT_LOAD segments. |
| 3092 | if ((*p)->has_load_address()) |
| 3093 | gold_error(_("may only specify load address for PT_LOAD segment")); |
| 3094 | continue; |
| 3095 | } |
| 3096 | |
| 3097 | // The output sections should have addresses from the SECTIONS |
| 3098 | // clause. The addresses don't have to be in order, so find the |
| 3099 | // one with the lowest load address. Use that to set the |
| 3100 | // address of the segment. |
| 3101 | |
| 3102 | Output_section* osec = oseg->section_with_lowest_load_address(); |
| 3103 | if (osec == NULL) |
| 3104 | { |
| 3105 | oseg->set_addresses(0, 0); |
| 3106 | continue; |
| 3107 | } |
| 3108 | |
| 3109 | uint64_t vma = osec->address(); |
| 3110 | uint64_t lma = osec->has_load_address() ? osec->load_address() : vma; |
| 3111 | |
| 3112 | // Override the load address of the section with the load |
| 3113 | // address specified for the segment. |
| 3114 | if ((*p)->has_load_address()) |
| 3115 | { |
| 3116 | if (osec->has_load_address()) |
| 3117 | gold_warning(_("PHDRS load address overrides " |
| 3118 | "section %s load address"), |
| 3119 | osec->name()); |
| 3120 | |
| 3121 | lma = (*p)->load_address(); |
| 3122 | } |
| 3123 | |
| 3124 | bool headers = (*p)->includes_filehdr() && (*p)->includes_phdrs(); |
| 3125 | if (!headers && ((*p)->includes_filehdr() || (*p)->includes_phdrs())) |
| 3126 | { |
| 3127 | // We could support this if we wanted to. |
| 3128 | gold_error(_("using only one of FILEHDR and PHDRS is " |
| 3129 | "not currently supported")); |
| 3130 | } |
| 3131 | if (headers) |
| 3132 | { |
| 3133 | size_t sizeof_headers = this->total_header_size(layout); |
| 3134 | uint64_t subtract = this->header_size_adjustment(lma, |
| 3135 | sizeof_headers); |
| 3136 | if (lma >= subtract && vma >= subtract) |
| 3137 | { |
| 3138 | lma -= subtract; |
| 3139 | vma -= subtract; |
| 3140 | } |
| 3141 | else |
| 3142 | { |
| 3143 | gold_error(_("sections loaded on first page without room " |
| 3144 | "for file and program headers " |
| 3145 | "are not supported")); |
| 3146 | } |
| 3147 | |
| 3148 | if (load_seg != NULL) |
| 3149 | gold_error(_("using FILEHDR and PHDRS on more than one " |
| 3150 | "PT_LOAD segment is not currently supported")); |
| 3151 | load_seg = oseg; |
| 3152 | } |
| 3153 | |
| 3154 | oseg->set_addresses(vma, lma); |
| 3155 | } |
| 3156 | |
| 3157 | return load_seg; |
| 3158 | } |
| 3159 | |
| 3160 | // Add the file header and segment headers to non-load segments |
| 3161 | // specified in the PHDRS clause. |
| 3162 | |
| 3163 | void |
| 3164 | Script_sections::put_headers_in_phdrs(Output_data* file_header, |
| 3165 | Output_data* segment_headers) |
| 3166 | { |
| 3167 | gold_assert(this->saw_phdrs_clause()); |
| 3168 | for (Phdrs_elements::iterator p = this->phdrs_elements_->begin(); |
| 3169 | p != this->phdrs_elements_->end(); |
| 3170 | ++p) |
| 3171 | { |
| 3172 | if ((*p)->type() != elfcpp::PT_LOAD) |
| 3173 | { |
| 3174 | if ((*p)->includes_phdrs()) |
| 3175 | (*p)->segment()->add_initial_output_data(segment_headers); |
| 3176 | if ((*p)->includes_filehdr()) |
| 3177 | (*p)->segment()->add_initial_output_data(file_header); |
| 3178 | } |
| 3179 | } |
| 3180 | } |
| 3181 | |
| 3182 | // Look for an output section by name and return the address, the load |
| 3183 | // address, the alignment, and the size. This is used when an |
| 3184 | // expression refers to an output section which was not actually |
| 3185 | // created. This returns true if the section was found, false |
| 3186 | // otherwise. |
| 3187 | |
| 3188 | bool |
| 3189 | Script_sections::get_output_section_info(const char* name, uint64_t* address, |
| 3190 | uint64_t* load_address, |
| 3191 | uint64_t* addralign, |
| 3192 | uint64_t* size) const |
| 3193 | { |
| 3194 | if (!this->saw_sections_clause_) |
| 3195 | return false; |
| 3196 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 3197 | p != this->sections_elements_->end(); |
| 3198 | ++p) |
| 3199 | if ((*p)->get_output_section_info(name, address, load_address, addralign, |
| 3200 | size)) |
| 3201 | return true; |
| 3202 | return false; |
| 3203 | } |
| 3204 | |
| 3205 | // Print the SECTIONS clause to F for debugging. |
| 3206 | |
| 3207 | void |
| 3208 | Script_sections::print(FILE* f) const |
| 3209 | { |
| 3210 | if (!this->saw_sections_clause_) |
| 3211 | return; |
| 3212 | |
| 3213 | fprintf(f, "SECTIONS {\n"); |
| 3214 | |
| 3215 | for (Sections_elements::const_iterator p = this->sections_elements_->begin(); |
| 3216 | p != this->sections_elements_->end(); |
| 3217 | ++p) |
| 3218 | (*p)->print(f); |
| 3219 | |
| 3220 | fprintf(f, "}\n"); |
| 3221 | |
| 3222 | if (this->phdrs_elements_ != NULL) |
| 3223 | { |
| 3224 | fprintf(f, "PHDRS {\n"); |
| 3225 | for (Phdrs_elements::const_iterator p = this->phdrs_elements_->begin(); |
| 3226 | p != this->phdrs_elements_->end(); |
| 3227 | ++p) |
| 3228 | (*p)->print(f); |
| 3229 | fprintf(f, "}\n"); |
| 3230 | } |
| 3231 | } |
| 3232 | |
| 3233 | } // End namespace gold. |