1// inremental.h -- incremental linking support for gold -*- C++ -*- 2 3// Copyright 2009, 2010 Free Software Foundation, Inc. 4// Written by Mikolaj Zalewski <mikolajz@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#ifndef GOLD_INCREMENTAL_H 24#define GOLD_INCREMENTAL_H 25 26#include <map> 27#include <vector> 28 29#include "elfcpp_file.h" 30#include "stringpool.h" 31#include "workqueue.h" 32#include "fileread.h" 33#include "output.h" 34 35namespace gold 36{ 37 38class Archive; 39class Input_argument; 40class Incremental_inputs_checker; 41class Incremental_script_entry; 42class Incremental_object_entry; 43class Incremental_archive_entry; 44class Incremental_inputs; 45class Object; 46 47// Incremental input type as stored in .gnu_incremental_inputs. 48 49enum Incremental_input_type 50{ 51 INCREMENTAL_INPUT_OBJECT = 1, 52 INCREMENTAL_INPUT_ARCHIVE_MEMBER = 2, 53 INCREMENTAL_INPUT_ARCHIVE = 3, 54 INCREMENTAL_INPUT_SHARED_LIBRARY = 4, 55 INCREMENTAL_INPUT_SCRIPT = 5 56}; 57 58// An object representing the ELF file we edit during an incremental build. 59// Similar to Object or Dynobj, but operates on Output_file and contains 60// method specific to file edition (TBD). This is the abstract parent class 61// implemented in Sized_incremental_binary<size, big_endian> for a specific 62// endianness and size. 63 64class Incremental_binary 65{ 66 public: 67 Incremental_binary(Output_file* output, Target* target) 68 : output_(output), target_(target) 69 { } 70 71 virtual 72 ~Incremental_binary() 73 { } 74 75 // Functions and types for the elfcpp::Elf_file interface. This 76 // permit us to use Incremental_binary as the File template parameter for 77 // elfcpp::Elf_file. 78 79 // The View class is returned by view. It must support a single 80 // method, data(). This is trivial, because Output_file::get_output_view 81 // does what we need. 82 class View 83 { 84 public: 85 View(const unsigned char* p) 86 : p_(p) 87 { } 88 89 const unsigned char* 90 data() const 91 { return this->p_; } 92 93 private: 94 const unsigned char* p_; 95 }; 96 97 // Return a View. 98 View 99 view(off_t file_offset, section_size_type data_size) 100 { return View(this->output_->get_input_view(file_offset, data_size)); } 101 102 // A location in the file. 103 struct Location 104 { 105 off_t file_offset; 106 off_t data_size; 107 108 Location(off_t fo, section_size_type ds) 109 : file_offset(fo), data_size(ds) 110 { } 111 112 Location() 113 : file_offset(0), data_size(0) 114 { } 115 }; 116 117 // Get a View given a Location. 118 View 119 view(Location loc) 120 { return View(this->view(loc.file_offset, loc.data_size)); } 121 122 // Report an error. 123 void 124 error(const char* format, ...) const ATTRIBUTE_PRINTF_2; 125 126 // Find the .gnu_incremental_inputs and related sections. It selects the 127 // first section of type SHT_GNU_INCREMENTAL_INPUTS, 128 // SHT_GNU_INCRMENTAL_SYMTAB, and SHT_GNU_INCREMENTAL_RELOCS. 129 // Returns false if the sections are not found. 130 bool 131 find_incremental_inputs_sections(unsigned int* p_inputs_shndx, 132 unsigned int* p_symtab_shndx, 133 unsigned int* p_relocs_shndx, 134 unsigned int* p_got_plt_shndx, 135 unsigned int* p_strtab_shndx) 136 { 137 return do_find_incremental_inputs_sections(p_inputs_shndx, p_symtab_shndx, 138 p_relocs_shndx, p_got_plt_shndx, 139 p_strtab_shndx); 140 } 141 142 // Check the .gnu_incremental_inputs section to see whether an incremental 143 // build is possible. 144 // TODO: on success, should report what files needs to be rebuilt. 145 // INCREMENTAL_INPUTS is used to read the canonical form of the command line 146 // and read the input arguments. TODO: for items that don't need to be 147 // rebuilt, we should also copy the incremental input information. 148 virtual bool 149 check_inputs(Incremental_inputs* incremental_inputs) 150 { return do_check_inputs(incremental_inputs); } 151 152 protected: 153 // Find incremental inputs section. 154 virtual bool 155 do_find_incremental_inputs_sections(unsigned int* p_inputs_shndx, 156 unsigned int* p_symtab_shndx, 157 unsigned int* p_relocs_shndx, 158 unsigned int* p_got_plt_shndx, 159 unsigned int* p_strtab_shndx) = 0; 160 161 // Check the .gnu_incremental_inputs section to see whether an incremental 162 // build is possible. 163 virtual bool 164 do_check_inputs(Incremental_inputs* incremental_inputs) = 0; 165 166 private: 167 // Edited output file object. 168 Output_file* output_; 169 // Target of the output file. 170 Target* target_; 171}; 172 173template<int size, bool big_endian> 174class Sized_incremental_binary : public Incremental_binary 175{ 176 public: 177 Sized_incremental_binary(Output_file* output, 178 const elfcpp::Ehdr<size, big_endian>& ehdr, 179 Target* target) 180 : Incremental_binary(output, target), elf_file_(this, ehdr) 181 { } 182 183 protected: 184 virtual bool 185 do_find_incremental_inputs_sections(unsigned int* p_inputs_shndx, 186 unsigned int* p_symtab_shndx, 187 unsigned int* p_relocs_shndx, 188 unsigned int* p_got_plt_shndx, 189 unsigned int* p_strtab_shndx); 190 191 virtual bool 192 do_check_inputs(Incremental_inputs* incremental_inputs); 193 194 private: 195 // Output as an ELF file. 196 elfcpp::Elf_file<size, big_endian, Incremental_binary> elf_file_; 197}; 198 199// Create an Incremental_binary object for FILE. Returns NULL is this is not 200// possible, e.g. FILE is not an ELF file or has an unsupported target. 201 202Incremental_binary* 203open_incremental_binary(Output_file* file); 204 205// Code invoked early during an incremental link that checks what files need 206// to be relinked. 207 208class Incremental_checker 209{ 210 public: 211 // Check if the file named OUTPUT_NAME can be linked incrementally. 212 // INCREMENTAL_INPUTS must have the canonical form of the command line 213 // and input arguments filled - at this point of linking other fields are 214 // probably not filled yet. TODO: for inputs that don't need to be 215 // rebuilt, this function should fill the incremental input information. 216 Incremental_checker(const char* output_name, 217 Incremental_inputs* incremental_inputs) 218 : output_name_(output_name), incremental_inputs_(incremental_inputs) 219 { } 220 221 // Analyzes the output file to check if incremental linking is possible and 222 // what files needs to be relinked. 223 bool 224 can_incrementally_link_output_file(); 225 226 private: 227 // Name of the output file to analyze. 228 const char* output_name_; 229 230 // The Incremental_inputs object. At this stage of link, only the command 231 // line and inputs are filled. 232 Incremental_inputs* incremental_inputs_; 233}; 234 235// Base class for recording each input file. 236 237class Incremental_input_entry 238{ 239 public: 240 Incremental_input_entry(Stringpool::Key filename_key, Timespec mtime) 241 : filename_key_(filename_key), offset_(0), info_offset_(0), mtime_(mtime) 242 { } 243 244 virtual 245 ~Incremental_input_entry() 246 { } 247 248 // Return the type of input file. 249 Incremental_input_type 250 type() const 251 { return this->do_type(); } 252 253 // Set the section offset of this input file entry. 254 void 255 set_offset(unsigned int offset) 256 { this->offset_ = offset; } 257 258 // Set the section offset of the supplemental information for this entry. 259 void 260 set_info_offset(unsigned int info_offset) 261 { this->info_offset_ = info_offset; } 262 263 // Get the section offset of this input file entry. 264 unsigned int 265 get_offset() const 266 { return this->offset_; } 267 268 // Get the section offset of the supplemental information for this entry. 269 unsigned int 270 get_info_offset() const 271 { return this->info_offset_; } 272 273 // Get the stringpool key for the input filename. 274 Stringpool::Key 275 get_filename_key() const 276 { return this->filename_key_; } 277 278 // Get the modification time of the input file. 279 const Timespec& 280 get_mtime() const 281 { return this->mtime_; } 282 283 // Return a pointer to the derived Incremental_script_entry object. 284 // Return NULL for input entries that are not script files. 285 Incremental_script_entry* 286 script_entry() 287 { return this->do_script_entry(); } 288 289 // Return a pointer to the derived Incremental_object_entry object. 290 // Return NULL for input entries that are not object files. 291 Incremental_object_entry* 292 object_entry() 293 { return this->do_object_entry(); } 294 295 // Return a pointer to the derived Incremental_archive_entry object. 296 // Return NULL for input entries that are not archive files. 297 Incremental_archive_entry* 298 archive_entry() 299 { return this->do_archive_entry(); } 300 301 protected: 302 // Return the type of input file. 303 virtual Incremental_input_type 304 do_type() const = 0; 305 306 // Return a pointer to the derived Incremental_script_entry object. 307 // Return NULL for input entries that are not script files. 308 virtual Incremental_script_entry* 309 do_script_entry() 310 { return NULL; } 311 312 // Return a pointer to the derived Incremental_object_entry object. 313 // Return NULL for input entries that are not object files. 314 virtual Incremental_object_entry* 315 do_object_entry() 316 { return NULL; } 317 318 // Return a pointer to the derived Incremental_archive_entry object. 319 // Return NULL for input entries that are not archive files. 320 virtual Incremental_archive_entry* 321 do_archive_entry() 322 { return NULL; } 323 324 private: 325 // Key of the filename string in the section stringtable. 326 Stringpool::Key filename_key_; 327 328 // Offset of the entry in the output section. 329 unsigned int offset_; 330 331 // Offset of the extra information in the output section. 332 unsigned int info_offset_; 333 334 // Last modification time of the file. 335 Timespec mtime_; 336}; 337 338// Class for recording input scripts. 339 340class Incremental_script_entry : public Incremental_input_entry 341{ 342 public: 343 Incremental_script_entry(Stringpool::Key filename_key, Script_info* script, 344 Timespec mtime) 345 : Incremental_input_entry(filename_key, mtime), script_(script) 346 { } 347 348 protected: 349 virtual Incremental_input_type 350 do_type() const 351 { return INCREMENTAL_INPUT_SCRIPT; } 352 353 // Return a pointer to the derived Incremental_script_entry object. 354 virtual Incremental_script_entry* 355 do_script_entry() 356 { return this; } 357 358 private: 359 // Information about the script file. 360 Script_info* script_; 361}; 362 363// Class for recording input object files. 364 365class Incremental_object_entry : public Incremental_input_entry 366{ 367 public: 368 Incremental_object_entry(Stringpool::Key filename_key, Object* obj, 369 Timespec mtime) 370 : Incremental_input_entry(filename_key, mtime), obj_(obj), 371 is_member_(false), sections_() 372 { 373 if (!obj_->is_dynamic()) 374 this->sections_.reserve(obj->shnum()); 375 } 376 377 // Get the object. 378 Object* 379 object() const 380 { return this->obj_; } 381 382 // Record that this object is an archive member. 383 void 384 set_is_member() 385 { this->is_member_ = true; } 386 387 // Return true if this object is an archive member. 388 bool 389 is_member() const 390 { return this->is_member_; } 391 392 // Add an input section. 393 void 394 add_input_section(unsigned int shndx, Stringpool::Key name_key, off_t sh_size) 395 { 396 if (shndx >= this->sections_.size()) 397 this->sections_.resize(shndx + 1); 398 this->sections_[shndx].name_key = name_key; 399 this->sections_[shndx].sh_size = sh_size; 400 } 401 402 // Return the number of input sections in this object. 403 unsigned int 404 get_input_section_count() const 405 { return this->sections_.size(); } 406 407 // Return the stringpool key of the Nth input section. 408 Stringpool::Key 409 get_input_section_name_key(unsigned int n) const 410 { return this->sections_[n].name_key; } 411 412 // Return the size of the Nth input section. 413 off_t 414 get_input_section_size(unsigned int n) const 415 { return this->sections_[n].sh_size; } 416 417 protected: 418 virtual Incremental_input_type 419 do_type() const 420 { 421 return (this->is_member_ 422 ? INCREMENTAL_INPUT_ARCHIVE_MEMBER 423 : (this->obj_->is_dynamic() 424 ? INCREMENTAL_INPUT_SHARED_LIBRARY 425 : INCREMENTAL_INPUT_OBJECT)); 426 } 427 428 // Return a pointer to the derived Incremental_object_entry object. 429 virtual Incremental_object_entry* 430 do_object_entry() 431 { return this; } 432 433 private: 434 // The object file itself. 435 Object* obj_; 436 437 // Whether this object is an archive member. 438 bool is_member_; 439 440 // Input sections. 441 struct Input_section 442 { 443 Stringpool::Key name_key; 444 off_t sh_size; 445 }; 446 std::vector<Input_section> sections_; 447}; 448 449// Class for recording archive library input files. 450 451class Incremental_archive_entry : public Incremental_input_entry 452{ 453 public: 454 Incremental_archive_entry(Stringpool::Key filename_key, Archive*, 455 Timespec mtime) 456 : Incremental_input_entry(filename_key, mtime), members_(), unused_syms_() 457 { } 458 459 // Add a member object to the archive. 460 void 461 add_object(Incremental_object_entry* obj_entry) 462 { 463 this->members_.push_back(obj_entry); 464 obj_entry->set_is_member(); 465 } 466 467 // Add an unused global symbol to the archive. 468 void 469 add_unused_global_symbol(Stringpool::Key symbol_key) 470 { this->unused_syms_.push_back(symbol_key); } 471 472 // Return the number of member objects included in the link. 473 unsigned int 474 get_member_count() 475 { return this->members_.size(); } 476 477 // Return the Nth member object. 478 Incremental_object_entry* 479 get_member(unsigned int n) 480 { return this->members_[n]; } 481 482 // Return the number of unused global symbols in this archive. 483 unsigned int 484 get_unused_global_symbol_count() 485 { return this->unused_syms_.size(); } 486 487 // Return the Nth unused global symbol. 488 Stringpool::Key 489 get_unused_global_symbol(unsigned int n) 490 { return this->unused_syms_[n]; } 491 492 protected: 493 virtual Incremental_input_type 494 do_type() const 495 { return INCREMENTAL_INPUT_ARCHIVE; } 496 497 // Return a pointer to the derived Incremental_archive_entry object. 498 virtual Incremental_archive_entry* 499 do_archive_entry() 500 { return this; } 501 502 private: 503 // Members of the archive that have been included in the link. 504 std::vector<Incremental_object_entry*> members_; 505 506 // Unused global symbols from this archive. 507 std::vector<Stringpool::Key> unused_syms_; 508}; 509 510// This class contains the information needed during an incremental 511// build about the inputs necessary to build the .gnu_incremental_inputs. 512 513class Incremental_inputs 514{ 515 public: 516 typedef std::vector<Incremental_input_entry*> Input_list; 517 518 Incremental_inputs() 519 : inputs_(), command_line_(), command_line_key_(0), 520 strtab_(new Stringpool()), current_object_(NULL), 521 current_object_entry_(NULL), inputs_section_(NULL), 522 symtab_section_(NULL), relocs_section_(NULL), 523 reloc_count_(0) 524 { } 525 526 ~Incremental_inputs() { delete this->strtab_; } 527 528 // Record the command line. 529 void 530 report_command_line(int argc, const char* const* argv); 531 532 // Record the initial info for archive file ARCHIVE. 533 void 534 report_archive_begin(Archive* arch); 535 536 // Record the final info for archive file ARCHIVE. 537 void 538 report_archive_end(Archive* arch); 539 540 // Record the info for object file OBJ. If ARCH is not NULL, 541 // attach the object file to the archive. 542 void 543 report_object(Object* obj, Archive* arch); 544 545 // Record an input section belonging to object file OBJ. 546 void 547 report_input_section(Object* obj, unsigned int shndx, const char* name, 548 off_t sh_size); 549 550 // Record the info for input script SCRIPT. 551 void 552 report_script(const std::string& filename, Script_info* script, 553 Timespec mtime); 554 555 // Return the running count of incremental relocations. 556 unsigned int 557 get_reloc_count() const 558 { return this->reloc_count_; } 559 560 // Update the running count of incremental relocations. 561 void 562 set_reloc_count(unsigned int count) 563 { this->reloc_count_ = count; } 564 565 // Prepare for layout. Called from Layout::finalize. 566 void 567 finalize(); 568 569 // Create the .gnu_incremental_inputs and related sections. 570 void 571 create_data_sections(Symbol_table* symtab); 572 573 // Return the .gnu_incremental_inputs section. 574 Output_section_data* 575 inputs_section() const 576 { return this->inputs_section_; } 577 578 // Return the .gnu_incremental_symtab section. 579 Output_data_space* 580 symtab_section() const 581 { return this->symtab_section_; } 582 583 // Return the .gnu_incremental_relocs section. 584 Output_data_space* 585 relocs_section() const 586 { return this->relocs_section_; } 587 588 // Return the .gnu_incremental_got_plt section. 589 Output_data_space* 590 got_plt_section() const 591 { return this->got_plt_section_; } 592 593 // Return the .gnu_incremental_strtab stringpool. 594 Stringpool* 595 get_stringpool() const 596 { return this->strtab_; } 597 598 // Return the canonical form of the command line, as will be stored in 599 // .gnu_incremental_strtab. 600 const std::string& 601 command_line() const 602 { return this->command_line_; } 603 604 // Return the stringpool key of the command line. 605 Stringpool::Key 606 command_line_key() const 607 { return this->command_line_key_; } 608 609 // Return the number of input files. 610 int 611 input_file_count() const 612 { return this->inputs_.size(); } 613 614 // Return the input files. 615 const Input_list& 616 input_files() const 617 { return this->inputs_; } 618 619 // Return the sh_entsize value for the .gnu_incremental_relocs section. 620 unsigned int 621 relocs_entsize() const; 622 623 private: 624 // The list of input files. 625 Input_list inputs_; 626 627 // Canonical form of the command line, as will be stored in 628 // .gnu_incremental_strtab. 629 std::string command_line_; 630 631 // The key of the command line string in the string pool. 632 Stringpool::Key command_line_key_; 633 634 // The .gnu_incremental_strtab string pool associated with the 635 // .gnu_incremental_inputs. 636 Stringpool* strtab_; 637 638 // Keep track of the object currently being processed. 639 Object* current_object_; 640 Incremental_object_entry* current_object_entry_; 641 642 // The .gnu_incremental_inputs section. 643 Output_section_data* inputs_section_; 644 645 // The .gnu_incremental_symtab section. 646 Output_data_space* symtab_section_; 647 648 // The .gnu_incremental_relocs section. 649 Output_data_space* relocs_section_; 650 651 // The .gnu_incremental_got_plt section. 652 Output_data_space* got_plt_section_; 653 654 // Total count of incremental relocations. Updated during Scan_relocs 655 // phase at the completion of each object file. 656 unsigned int reloc_count_; 657}; 658 659// Reader class for .gnu_incremental_inputs section. 660 661template<int size, bool big_endian> 662class Incremental_inputs_reader 663{ 664 private: 665 typedef elfcpp::Swap<size, big_endian> Swap; 666 typedef elfcpp::Swap<16, big_endian> Swap16; 667 typedef elfcpp::Swap<32, big_endian> Swap32; 668 typedef elfcpp::Swap<64, big_endian> Swap64; 669 670 public: 671 Incremental_inputs_reader(const unsigned char* p, elfcpp::Elf_strtab& strtab) 672 : p_(p), strtab_(strtab) 673 { this->input_file_count_ = Swap32::readval(this->p_ + 4); } 674 675 // Return the version number. 676 unsigned int 677 version() const 678 { return Swap32::readval(this->p_); } 679 680 // Return the count of input file entries. 681 unsigned int 682 input_file_count() const 683 { return this->input_file_count_; } 684 685 // Return the command line. 686 const char* 687 command_line() const 688 { 689 unsigned int offset = Swap32::readval(this->p_ + 8); 690 return this->get_string(offset); 691 } 692 693 // Reader class for an input file entry and its supplemental info. 694 class Incremental_input_entry_reader 695 { 696 public: 697 Incremental_input_entry_reader(const Incremental_inputs_reader* inputs, 698 unsigned int offset) 699 : inputs_(inputs), offset_(offset) 700 { 701 this->info_offset_ = Swap32::readval(inputs->p_ + offset + 4); 702 int type = Swap16::readval(this->inputs_->p_ + offset + 20); 703 this->type_ = static_cast<Incremental_input_type>(type); 704 } 705 706 // Return the filename. 707 const char* 708 filename() const 709 { 710 unsigned int offset = Swap32::readval(this->inputs_->p_ + this->offset_); 711 return this->inputs_->get_string(offset); 712 } 713 714 // Return the timestamp. 715 Timespec 716 get_mtime() const 717 { 718 Timespec t; 719 const unsigned char* p = this->inputs_->p_ + this->offset_ + 8; 720 t.seconds = Swap64::readval(p); 721 t.nanoseconds = Swap32::readval(p+8); 722 return t; 723 } 724 725 // Return the type of input file. 726 Incremental_input_type 727 type() const 728 { return this->type_; } 729 730 // Return the input section count -- for objects only. 731 unsigned int 732 get_input_section_count() const 733 { 734 gold_assert(this->type_ == INCREMENTAL_INPUT_OBJECT 735 || this->type_ == INCREMENTAL_INPUT_ARCHIVE_MEMBER); 736 return Swap32::readval(this->inputs_->p_ + this->info_offset_); 737 } 738 739 // Return the offset of the supplemental info for symbol SYMNDX -- 740 // for objects only. 741 unsigned int 742 get_symbol_offset(unsigned int symndx) const 743 { 744 gold_assert(this->type_ == INCREMENTAL_INPUT_OBJECT 745 || this->type_ == INCREMENTAL_INPUT_ARCHIVE_MEMBER); 746 747 unsigned int section_count = this->get_input_section_count(); 748 return (this->info_offset_ + 8 749 + section_count * input_section_entry_size 750 + symndx * 16); 751 } 752 753 // Return the global symbol count -- for objects & shared libraries only. 754 unsigned int 755 get_global_symbol_count() const 756 { 757 switch (this->type_) 758 { 759 case INCREMENTAL_INPUT_OBJECT: 760 case INCREMENTAL_INPUT_ARCHIVE_MEMBER: 761 return Swap32::readval(this->inputs_->p_ + this->info_offset_ + 4); 762 case INCREMENTAL_INPUT_SHARED_LIBRARY: 763 return Swap32::readval(this->inputs_->p_ + this->info_offset_); 764 default: 765 gold_unreachable(); 766 } 767 } 768 769 // Return the member count -- for archives only. 770 unsigned int 771 get_member_count() const 772 { 773 gold_assert(this->type_ == INCREMENTAL_INPUT_ARCHIVE); 774 return Swap32::readval(this->inputs_->p_ + this->info_offset_); 775 } 776 777 // Return the unused symbol count -- for archives only. 778 unsigned int 779 get_unused_symbol_count() const 780 { 781 gold_assert(this->type_ == INCREMENTAL_INPUT_ARCHIVE); 782 return Swap32::readval(this->inputs_->p_ + this->info_offset_ + 4); 783 } 784 785 // Return the input file offset for archive member N -- for archives only. 786 unsigned int 787 get_member_offset(unsigned int n) const 788 { 789 gold_assert(this->type_ == INCREMENTAL_INPUT_ARCHIVE); 790 return Swap32::readval(this->inputs_->p_ + this->info_offset_ 791 + 8 + n * 4); 792 } 793 794 // Return the Nth unused global symbol -- for archives only. 795 const char* 796 get_unused_symbol(unsigned int n) const 797 { 798 gold_assert(this->type_ == INCREMENTAL_INPUT_ARCHIVE); 799 unsigned int member_count = this->get_member_count(); 800 unsigned int offset = Swap32::readval(this->inputs_->p_ 801 + this->info_offset_ + 8 802 + member_count * 4 803 + n * 4); 804 return this->inputs_->get_string(offset); 805 } 806 807 // Information about an input section. 808 struct Input_section_info 809 { 810 const char* name; 811 unsigned int output_shndx; 812 off_t sh_offset; 813 off_t sh_size; 814 }; 815 816 // Return info about the Nth input section -- for objects only. 817 Input_section_info 818 get_input_section(unsigned int n) const 819 { 820 Input_section_info info; 821 const unsigned char* p = (this->inputs_->p_ 822 + this->info_offset_ + 8 823 + n * input_section_entry_size); 824 unsigned int name_offset = Swap32::readval(p); 825 info.name = this->inputs_->get_string(name_offset); 826 info.output_shndx = Swap32::readval(p + 4); 827 info.sh_offset = Swap::readval(p + 8); 828 info.sh_size = Swap::readval(p + 8 + size / 8); 829 return info; 830 } 831 832 // Information about a global symbol. 833 struct Global_symbol_info 834 { 835 unsigned int output_symndx; 836 unsigned int next_offset; 837 unsigned int reloc_count; 838 unsigned int reloc_offset; 839 }; 840 841 // Return info about the Nth global symbol -- for objects only. 842 Global_symbol_info 843 get_global_symbol_info(unsigned int n) const 844 { 845 Global_symbol_info info; 846 unsigned int section_count = this->get_input_section_count(); 847 const unsigned char* p = (this->inputs_->p_ 848 + this->info_offset_ + 8 849 + section_count * input_section_entry_size 850 + n * 16); 851 info.output_symndx = Swap32::readval(p); 852 info.next_offset = Swap32::readval(p + 4); 853 info.reloc_count = Swap::readval(p + 8); 854 info.reloc_offset = Swap::readval(p + 12); 855 return info; 856 } 857 858 private: 859 // Size of an input section entry. 860 static const unsigned int input_section_entry_size = 8 + 2 * size / 8; 861 // The reader instance for the containing section. 862 const Incremental_inputs_reader* inputs_; 863 // The type of input file. 864 Incremental_input_type type_; 865 // Section offset to the input file entry. 866 unsigned int offset_; 867 // Section offset to the supplemental info for the input file. 868 unsigned int info_offset_; 869 }; 870 871 // Return a reader for the Nth input file entry. 872 Incremental_input_entry_reader 873 input_file(unsigned int n) const 874 { 875 gold_assert(n < this->input_file_count_); 876 Incremental_input_entry_reader input(this, 16 + n * 24); 877 return input; 878 } 879 880 private: 881 // Lookup a string in the ELF string table. 882 const char* get_string(unsigned int offset) const 883 { 884 const char* s; 885 if (this->strtab_.get_c_string(offset, &s)) 886 return s; 887 return NULL; 888 } 889 890 // Base address of the .gnu_incremental_inputs section. 891 const unsigned char* p_; 892 // The associated ELF string table. 893 elfcpp::Elf_strtab strtab_; 894 // The number of input file entries in this section. 895 unsigned int input_file_count_; 896}; 897 898// Reader class for the .gnu_incremental_symtab section. 899 900template<bool big_endian> 901class Incremental_symtab_reader 902{ 903 public: 904 Incremental_symtab_reader(const unsigned char* p) : p_(p) 905 { } 906 907 // Return the list head for symbol table entry N. 908 unsigned int get_list_head(unsigned int n) const 909 { return elfcpp::Swap<32, big_endian>::readval(this->p_ + 4 * n); } 910 911 private: 912 // Base address of the .gnu_incremental_relocs section. 913 const unsigned char* p_; 914}; 915 916// Reader class for the .gnu_incremental_relocs section. 917 918template<int size, bool big_endian> 919class Incremental_relocs_reader 920{ 921 private: 922 // Size of each field. 923 static const unsigned int field_size = size / 8; 924 925 public: 926 typedef typename elfcpp::Elf_types<size>::Elf_Addr Address; 927 typedef typename elfcpp::Elf_types<size>::Elf_Swxword Addend; 928 929 // Size of each entry. 930 static const unsigned int reloc_size = 8 + 2 * field_size; 931 932 Incremental_relocs_reader(const unsigned char* p) : p_(p) 933 { } 934 935 // Return the relocation type for relocation entry at offset OFF. 936 unsigned int 937 get_r_type(unsigned int off) const 938 { 939 return elfcpp::Swap<32, big_endian>::readval(this->p_ + off); 940 } 941 942 // Return the output section index for relocation entry at offset OFF. 943 unsigned int 944 get_r_shndx(unsigned int off) const 945 { 946 return elfcpp::Swap<32, big_endian>::readval(this->p_ + off + 4); 947 } 948 949 // Return the output section offset for relocation entry at offset OFF. 950 Address 951 get_r_offset(unsigned int off) const 952 { 953 return elfcpp::Swap<size, big_endian>::readval(this->p_ + off + 8); 954 } 955 956 // Return the addend for relocation entry at offset OFF. 957 Addend 958 get_r_addend(unsigned int off) const 959 { 960 return elfcpp::Swap<size, big_endian>::readval(this->p_ + off + 8 961 + this->field_size); 962 } 963 964 private: 965 // Base address of the .gnu_incremental_relocs section. 966 const unsigned char* p_; 967}; 968 969// Reader class for the .gnu_incremental_got_plt section. 970 971template<bool big_endian> 972class Incremental_got_plt_reader 973{ 974 public: 975 Incremental_got_plt_reader(const unsigned char* p) : p_(p) 976 { 977 this->got_count_ = elfcpp::Swap<32, big_endian>::readval(p); 978 this->got_desc_p_ = p + 8 + ((this->got_count_ + 3) & ~3); 979 this->plt_desc_p_ = this->got_desc_p_ + this->got_count_ * 4; 980 } 981 982 // Return the GOT entry count. 983 unsigned int 984 get_got_entry_count() const 985 { 986 return this->got_count_; 987 } 988 989 // Return the PLT entry count. 990 unsigned int 991 get_plt_entry_count() const 992 { 993 return elfcpp::Swap<32, big_endian>::readval(this->p_ + 4); 994 } 995 996 // Return the GOT type for GOT entry N. 997 unsigned int 998 get_got_type(unsigned int n) 999 { 1000 return this->p_[8 + n]; 1001 } 1002 1003 // Return the GOT descriptor for GOT entry N. 1004 unsigned int 1005 get_got_desc(unsigned int n) 1006 { 1007 return elfcpp::Swap<32, big_endian>::readval(this->got_desc_p_ + n * 4); 1008 } 1009 1010 // Return the PLT descriptor for PLT entry N. 1011 unsigned int 1012 get_plt_desc(unsigned int n) 1013 { 1014 return elfcpp::Swap<32, big_endian>::readval(this->plt_desc_p_ + n * 4); 1015 } 1016 1017 private: 1018 // Base address of the .gnu_incremental_got_plt section. 1019 const unsigned char* p_; 1020 // GOT entry count. 1021 unsigned int got_count_; 1022 // Base address of the GOT descriptor array. 1023 const unsigned char* got_desc_p_; 1024 // Base address of the PLT descriptor array. 1025 const unsigned char* plt_desc_p_; 1026}; 1027 1028} // End namespace gold. 1029 1030#endif // !defined(GOLD_INCREMENTAL_H) 1031