gold/layout.h

   1 // layout.h -- lay out output file sections for gold  -*- C++ -*-
   2
   3 // Copyright 2006, 2007, 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 #ifndef GOLD_LAYOUT_H
  24 #define GOLD_LAYOUT_H
  25
  26 #include <list>
  27 #include <string>
  28 #include <utility>
  29 #include <vector>
  30
  31 #include "script.h"
  32 #include "workqueue.h"
  33 #include "object.h"
  34 #include "dynobj.h"
  35 #include "stringpool.h"
  36
  37 namespace gold
  38 {
  39
  40 class General_options;
  41 class Input_objects;
  42 class Symbol_table;
  43 class Output_section_data;
  44 class Output_section;
  45 class Output_section_headers;
  46 class Output_segment;
  47 class Output_data;
  48 class Output_data_dynamic;
  49 class Eh_frame;
  50 class Target;
  51
  52 // This task function handles mapping the input sections to output
  53 // sections and laying them out in memory.
  54
  55 class Layout_task_runner : public Task_function_runner
  56 {
  57  public:
  58   // OPTIONS is the command line options, INPUT_OBJECTS is the list of
  59   // input objects, SYMTAB is the symbol table, LAYOUT is the layout
  60   // object.
  61   Layout_task_runner(const General_options& options,
  62                      const Input_objects* input_objects,
  63                      Symbol_table* symtab,
  64                      Target* target,
  65                      Layout* layout)
  66     : options_(options), input_objects_(input_objects), symtab_(symtab),
  67       target_(target), layout_(layout)
  68   { }
  69
  70   // Run the operation.
  71   void
  72   run(Workqueue*, const Task*);
  73
  74  private:
  75   Layout_task_runner(const Layout_task_runner&);
  76   Layout_task_runner& operator=(const Layout_task_runner&);
  77
  78   const General_options& options_;
  79   const Input_objects* input_objects_;
  80   Symbol_table* symtab_;
  81   Target* target_;
  82   Layout* layout_;
  83 };
  84
  85 // This class handles the details of laying out input sections.
  86
  87 class Layout
  88 {
  89  public:
  90   Layout(const General_options& options, Script_options*);
  91
  92   // Given an input section SHNDX, named NAME, with data in SHDR, from
  93   // the object file OBJECT, return the output section where this
  94   // input section should go.  RELOC_SHNDX is the index of a
  95   // relocation section which applies to this section, or 0 if none,
  96   // or -1U if more than one.  RELOC_TYPE is the type of the
  97   // relocation section if there is one.  Set *OFFSET to the offset
  98   // within the output section.
  99   template<int size, bool big_endian>
 100   Output_section*
 101   layout(Sized_relobj<size, big_endian> *object, unsigned int shndx,
 102          const char* name, const elfcpp::Shdr<size, big_endian>& shdr,
 103          unsigned int reloc_shndx, unsigned int reloc_type, off_t* offset);
 104
 105   // Layout an input reloc section when doing a relocatable link.  The
 106   // section is RELOC_SHNDX in OBJECT, with data in SHDR.
 107   // DATA_SECTION is the reloc section to which it refers.  RR is the
 108   // relocatable information.
 109   template<int size, bool big_endian>
 110   Output_section*
 111   layout_reloc(Sized_relobj<size, big_endian>* object,
 112                unsigned int reloc_shndx,
 113                const elfcpp::Shdr<size, big_endian>& shdr,
 114                Output_section* data_section,
 115                Relocatable_relocs* rr);
 116
 117   // Layout a group section when doing a relocatable link.
 118   template<int size, bool big_endian>
 119   void
 120   layout_group(Symbol_table* symtab,
 121                Sized_relobj<size, big_endian>* object,
 122                unsigned int group_shndx,
 123                const char* group_section_name,
 124                const char* signature,
 125                const elfcpp::Shdr<size, big_endian>& shdr,
 126                const elfcpp::Elf_Word* contents);
 127
 128   // Like layout, only for exception frame sections.  OBJECT is an
 129   // object file.  SYMBOLS is the contents of the symbol table
 130   // section, with size SYMBOLS_SIZE.  SYMBOL_NAMES is the contents of
 131   // the symbol name section, with size SYMBOL_NAMES_SIZE.  SHNDX is a
 132   // .eh_frame section in OBJECT.  SHDR is the section header.
 133   // RELOC_SHNDX is the index of a relocation section which applies to
 134   // this section, or 0 if none, or -1U if more than one.  RELOC_TYPE
 135   // is the type of the relocation section if there is one.  This
 136   // returns the output section, and sets *OFFSET to the offset.
 137   template<int size, bool big_endian>
 138   Output_section*
 139   layout_eh_frame(Sized_relobj<size, big_endian>* object,
 140                   const unsigned char* symbols,
 141                   off_t symbols_size,
 142                   const unsigned char* symbol_names,
 143                   off_t symbol_names_size,
 144                   unsigned int shndx,
 145                   const elfcpp::Shdr<size, big_endian>& shdr,
 146                   unsigned int reloc_shndx, unsigned int reloc_type,
 147                   off_t* offset);
 148
 149   // Handle a GNU stack note.  This is called once per input object
 150   // file.  SEEN_GNU_STACK is true if the object file has a
 151   // .note.GNU-stack section.  GNU_STACK_FLAGS is the section flags
 152   // from that section if there was one.
 153   void
 154   layout_gnu_stack(bool seen_gnu_stack, uint64_t gnu_stack_flags);
 155
 156   // Add an Output_section_data to the layout.  This is used for
 157   // special sections like the GOT section.
 158   void
 159   add_output_section_data(const char* name, elfcpp::Elf_Word type,
 160                           elfcpp::Elf_Xword flags,
 161                           Output_section_data*);
 162
 163   // Create dynamic sections if necessary.
 164   void
 165   create_initial_dynamic_sections(Symbol_table*);
 166
 167   // Define __start and __stop symbols for output sections.
 168   void
 169   define_section_symbols(Symbol_table*);
 170
 171   // Create sections for linker scripts.
 172   void
 173   create_script_sections()
 174   { this->script_options_->create_script_sections(this); }
 175
 176   // Define symbols from any linker script.
 177   void
 178   define_script_symbols(Symbol_table* symtab)
 179   { this->script_options_->add_symbols_to_table(symtab); }
 180
 181   // Define symbols for group signatures.
 182   void
 183   define_group_signatures(Symbol_table*);
 184
 185   // Return the Stringpool used for symbol names.
 186   const Stringpool*
 187   sympool() const
 188   { return &this->sympool_; }
 189
 190   // Return the Stringpool used for dynamic symbol names and dynamic
 191   // tags.
 192   const Stringpool*
 193   dynpool() const
 194   { return &this->dynpool_; }
 195
 196   // Return whether a section is a .gnu.linkonce section, given the
 197   // section name.
 198   static inline bool
 199   is_linkonce(const char* name)
 200   { return strncmp(name, ".gnu.linkonce", sizeof(".gnu.linkonce") - 1) == 0; }
 201
 202   // Record the signature of a comdat section, and return whether to
 203   // include it in the link.  The GROUP parameter is true for a
 204   // section group signature, false for a signature derived from a
 205   // .gnu.linkonce section.
 206   bool
 207   add_comdat(const char*, bool group);
 208
 209   // Finalize the layout after all the input sections have been added.
 210   off_t
 211   finalize(const Input_objects*, Symbol_table*, Target*, const Task*);
 212
 213   // Return whether any sections require postprocessing.
 214   bool
 215   any_postprocessing_sections() const
 216   { return this->any_postprocessing_sections_; }
 217
 218   // Return the size of the output file.
 219   off_t
 220   output_file_size() const
 221   { return this->output_file_size_; }
 222
 223   // Return the TLS segment.  This will return NULL if there isn't
 224   // one.
 225   Output_segment*
 226   tls_segment() const
 227   { return this->tls_segment_; }
 228
 229   // Return the normal symbol table.
 230   Output_section*
 231   symtab_section() const
 232   {
 233     gold_assert(this->symtab_section_ != NULL);
 234     return this->symtab_section_;
 235   }
 236
 237   // Return the dynamic symbol table.
 238   Output_section*
 239   dynsym_section() const
 240   {
 241     gold_assert(this->dynsym_section_ != NULL);
 242     return this->dynsym_section_;
 243   }
 244
 245   // Return the dynamic tags.
 246   Output_data_dynamic*
 247   dynamic_data() const
 248   { return this->dynamic_data_; }
 249
 250   // Write out the output sections.
 251   void
 252   write_output_sections(Output_file* of) const;
 253
 254   // Write out data not associated with an input file or the symbol
 255   // table.
 256   void
 257   write_data(const Symbol_table*, Output_file*) const;
 258
 259   // Write out output sections which can not be written until all the
 260   // input sections are complete.
 261   void
 262   write_sections_after_input_sections(Output_file* of);
 263
 264   // Return an output section named NAME, or NULL if there is none.
 265   Output_section*
 266   find_output_section(const char* name) const;
 267
 268   // Return an output segment of type TYPE, with segment flags SET set
 269   // and segment flags CLEAR clear.  Return NULL if there is none.
 270   Output_segment*
 271   find_output_segment(elfcpp::PT type, elfcpp::Elf_Word set,
 272                       elfcpp::Elf_Word clear) const;
 273
 274   // Return the number of segments we expect to produce.
 275   size_t
 276   expected_segment_count() const;
 277
 278   // Set a flag to indicate that an object file uses the static TLS model.
 279   void
 280   set_has_static_tls()
 281   { this->has_static_tls_ = true; }
 282
 283   // Return true if any object file uses the static TLS model.
 284   bool
 285   has_static_tls() const
 286   { return this->has_static_tls_; }
 287
 288   // Return the options which may be set by a linker script.
 289   Script_options*
 290   script_options()
 291   { return this->script_options_; }
 292
 293   const Script_options*
 294   script_options() const
 295   { return this->script_options_; }
 296
 297   // Rewrite output file in binary format.
 298   void
 299   write_binary(Output_file* in) const;
 300
 301   // Dump statistical information to stderr.
 302   void
 303   print_stats() const;
 304
 305   // A list of segments.
 306
 307   typedef std::vector<Output_segment*> Segment_list;
 308
 309   // A list of sections.
 310
 311   typedef std::vector<Output_section*> Section_list;
 312
 313   // The list of information to write out which is not attached to
 314   // either a section or a segment.
 315   typedef std::vector<Output_data*> Data_list;
 316
 317   // Store the allocated sections into the section list.  This is used
 318   // by the linker script code.
 319   void
 320   get_allocated_sections(Section_list*) const;
 321
 322   // Make a section for a linker script to hold data.
 323   Output_section*
 324   make_output_section_for_script(const char* name);
 325
 326   // Make a segment.  This is used by the linker script code.
 327   Output_segment*
 328   make_output_segment(elfcpp::Elf_Word type, elfcpp::Elf_Word flags);
 329
 330   // Return the number of segments.
 331   size_t
 332   segment_count() const
 333   { return this->segment_list_.size(); }
 334
 335   // Map from section flags to segment flags.
 336   static elfcpp::Elf_Word
 337   section_flags_to_segment(elfcpp::Elf_Xword flags);
 338
 339  private:
 340   Layout(const Layout&);
 341   Layout& operator=(const Layout&);
 342
 343   // Mapping from .gnu.linkonce section names to output section names.
 344   struct Linkonce_mapping
 345   {
 346     const char* from;
 347     int fromlen;
 348     const char* to;
 349     int tolen;
 350   };
 351   static const Linkonce_mapping linkonce_mapping[];
 352   static const int linkonce_mapping_count;
 353
 354   // During a relocatable link, a list of group sections and
 355   // signatures.
 356   struct Group_signature
 357   {
 358     // The group section.
 359     Output_section* section;
 360     // The signature.
 361     const char* signature;
 362
 363     Group_signature()
 364       : section(NULL), signature(NULL)
 365     { }
 366
 367     Group_signature(Output_section* sectiona, const char* signaturea)
 368       : section(sectiona), signature(signaturea)
 369     { }
 370   };
 371   typedef std::vector<Group_signature> Group_signatures;
 372
 373   // Create a .note section for gold.
 374   void
 375   create_gold_note();
 376
 377   // Record whether the stack must be executable.
 378   void
 379   create_executable_stack_info(const Target*);
 380
 381   // Find the first read-only PT_LOAD segment, creating one if
 382   // necessary.
 383   Output_segment*
 384   find_first_load_seg();
 385
 386   // Count the local symbols in the regular symbol table and the dynamic
 387   // symbol table, and build the respective string pools.
 388   void
 389   count_local_symbols(const Task*, const Input_objects*);
 390
 391   // Create the output sections for the symbol table.
 392   void
 393   create_symtab_sections(const Input_objects*, Symbol_table*, off_t*);
 394
 395   // Create the .shstrtab section.
 396   Output_section*
 397   create_shstrtab();
 398
 399   // Create the section header table.
 400   void
 401   create_shdrs(off_t*);
 402
 403   // Create the dynamic symbol table.
 404   void
 405   create_dynamic_symtab(const Input_objects*, Symbol_table*,
 406                         Output_section** pdynstr,
 407                         unsigned int* plocal_dynamic_count,
 408                         std::vector<Symbol*>* pdynamic_symbols,
 409                         Versions* versions);
 410
 411   // Assign offsets to each local portion of the dynamic symbol table.
 412   void
 413   assign_local_dynsym_offsets(const Input_objects*);
 414
 415   // Finish the .dynamic section and PT_DYNAMIC segment.
 416   void
 417   finish_dynamic_section(const Input_objects*, const Symbol_table*);
 418
 419   // Create the .interp section and PT_INTERP segment.
 420   void
 421   create_interp(const Target* target);
 422
 423   // Create the version sections.
 424   void
 425   create_version_sections(const Versions*,
 426                           const Symbol_table*,
 427                           unsigned int local_symcount,
 428                           const std::vector<Symbol*>& dynamic_symbols,
 429                           const Output_section* dynstr);
 430
 431   template<int size, bool big_endian>
 432   void
 433   sized_create_version_sections(const Versions* versions,
 434                                 const Symbol_table*,
 435                                 unsigned int local_symcount,
 436                                 const std::vector<Symbol*>& dynamic_symbols,
 437                                 const Output_section* dynstr);
 438
 439   // Return whether to include this section in the link.
 440   template<int size, bool big_endian>
 441   bool
 442   include_section(Sized_relobj<size, big_endian>* object, const char* name,
 443                   const elfcpp::Shdr<size, big_endian>&);
 444
 445   // Return the output section name to use given an input section
 446   // name.  Set *PLEN to the length of the name.  *PLEN must be
 447   // initialized to the length of NAME.
 448   static const char*
 449   output_section_name(const char* name, size_t* plen);
 450
 451   // Return the output section name to use for a linkonce section
 452   // name.  PLEN is as for output_section_name.
 453   static const char*
 454   linkonce_output_name(const char* name, size_t* plen);
 455
 456   // Return the output section for NAME, TYPE and FLAGS.
 457   Output_section*
 458   get_output_section(const char* name, Stringpool::Key name_key,
 459                      elfcpp::Elf_Word type, elfcpp::Elf_Xword flags);
 460
 461   // Choose the output section for NAME in RELOBJ.
 462   Output_section*
 463   choose_output_section(const Relobj* relobj, const char* name,
 464                         elfcpp::Elf_Word type, elfcpp::Elf_Xword flags,
 465                         bool adjust_name);
 466
 467   // Create a new Output_section.
 468   Output_section*
 469   make_output_section(const char* name, elfcpp::Elf_Word type,
 470                       elfcpp::Elf_Xword flags);
 471
 472   // Attach a section to a segment.
 473   void
 474   attach_to_segment(Output_section*, elfcpp::Elf_Xword flags);
 475
 476   // Allocate a previously unallocated output section.
 477   void
 478   allocate_output_section(Output_section*, elfcpp::Elf_Xword flags);
 479
 480   // Turn a read-only output section into a read-write output section.
 481   void
 482   write_enable_output_section(Output_section*, elfcpp::Elf_Xword flags);
 483
 484   // Set the final file offsets of all the segments.
 485   off_t
 486   set_segment_offsets(const Target*, Output_segment*, unsigned int* pshndx);
 487
 488   // Set the file offsets of the sections when doing a relocatable
 489   // link.
 490   off_t
 491   set_relocatable_section_offsets(Output_data*, unsigned int* pshndx);
 492
 493   // Set the final file offsets of all the sections not associated
 494   // with a segment.  We set section offsets in three passes: the
 495   // first handles all allocated sections, the second sections that
 496   // require postprocessing, and the last the late-bound STRTAB
 497   // sections (probably only shstrtab, which is the one we care about
 498   // because it holds section names).
 499   enum Section_offset_pass
 500   {
 501     BEFORE_INPUT_SECTIONS_PASS,
 502     POSTPROCESSING_SECTIONS_PASS,
 503     STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
 504   };
 505   off_t
 506   set_section_offsets(off_t, Section_offset_pass pass);
 507
 508   // Set the final section indexes of all the sections not associated
 509   // with a segment.  Returns the next unused index.
 510   unsigned int
 511   set_section_indexes(unsigned int pshndx);
 512
 513   // Set the section addresses when using a script.
 514   Output_segment*
 515   set_section_addresses_from_script(Symbol_table*);
 516
 517   // Return whether SEG1 comes before SEG2 in the output file.
 518   static bool
 519   segment_precedes(const Output_segment* seg1, const Output_segment* seg2);
 520
 521   // A mapping used for group signatures.
 522   typedef Unordered_map<std::string, bool> Signatures;
 523
 524   // Mapping from input section name/type/flags to output section.  We
 525   // use canonicalized strings here.
 526
 527   typedef std::pair<Stringpool::Key,
 528                     std::pair<elfcpp::Elf_Word, elfcpp::Elf_Xword> > Key;
 529
 530   struct Hash_key
 531   {
 532     size_t
 533     operator()(const Key& k) const;
 534   };
 535
 536   typedef Unordered_map<Key, Output_section*, Hash_key> Section_name_map;
 537
 538   // A comparison class for segments.
 539
 540   struct Compare_segments
 541   {
 542     bool
 543     operator()(const Output_segment* seg1, const Output_segment* seg2)
 544     { return Layout::segment_precedes(seg1, seg2); }
 545   };
 546
 547   // A reference to the options on the command line.
 548   const General_options& options_;
 549   // Information set by scripts or by command line options.
 550   Script_options* script_options_;
 551   // The output section names.
 552   Stringpool namepool_;
 553   // The output symbol names.
 554   Stringpool sympool_;
 555   // The dynamic strings, if needed.
 556   Stringpool dynpool_;
 557   // The list of group sections and linkonce sections which we have seen.
 558   Signatures signatures_;
 559   // The mapping from input section name/type/flags to output sections.
 560   Section_name_map section_name_map_;
 561   // The list of output segments.
 562   Segment_list segment_list_;
 563   // The list of output sections.
 564   Section_list section_list_;
 565   // The list of output sections which are not attached to any output
 566   // segment.
 567   Section_list unattached_section_list_;
 568   // The list of unattached Output_data objects which require special
 569   // handling because they are not Output_sections.
 570   Data_list special_output_list_;
 571   // The section headers.
 572   Output_section_headers* section_headers_;
 573   // A pointer to the PT_TLS segment if there is one.
 574   Output_segment* tls_segment_;
 575   // The SHT_SYMTAB output section.
 576   Output_section* symtab_section_;
 577   // The SHT_DYNSYM output section if there is one.
 578   Output_section* dynsym_section_;
 579   // The SHT_DYNAMIC output section if there is one.
 580   Output_section* dynamic_section_;
 581   // The dynamic data which goes into dynamic_section_.
 582   Output_data_dynamic* dynamic_data_;
 583   // The exception frame output section if there is one.
 584   Output_section* eh_frame_section_;
 585   // The exception frame data for eh_frame_section_.
 586   Eh_frame* eh_frame_data_;
 587   // The exception frame header output section if there is one.
 588   Output_section* eh_frame_hdr_section_;
 589   // A list of group sections and their signatures.
 590   Group_signatures group_signatures_;
 591   // The size of the output file.
 592   off_t output_file_size_;
 593   // Whether we have seen an object file marked to require an
 594   // executable stack.
 595   bool input_requires_executable_stack_;
 596   // Whether we have seen at least one object file with an executable
 597   // stack marker.
 598   bool input_with_gnu_stack_note_;
 599   // Whether we have seen at least one object file without an
 600   // executable stack marker.
 601   bool input_without_gnu_stack_note_;
 602   // Whether we have seen an object file that uses the static TLS model.
 603   bool has_static_tls_;
 604   // Whether any sections require postprocessing.
 605   bool any_postprocessing_sections_;
 606 };
 607
 608 // This task handles writing out data in output sections which is not
 609 // part of an input section, or which requires special handling.  When
 610 // this is done, it unblocks both output_sections_blocker and
 611 // final_blocker.
 612
 613 class Write_sections_task : public Task
 614 {
 615  public:
 616   Write_sections_task(const Layout* layout, Output_file* of,
 617                       Task_token* output_sections_blocker,
 618                       Task_token* final_blocker)
 619     : layout_(layout), of_(of),
 620       output_sections_blocker_(output_sections_blocker),
 621       final_blocker_(final_blocker)
 622   { }
 623
 624   // The standard Task methods.
 625
 626   Task_token*
 627   is_runnable();
 628
 629   void
 630   locks(Task_locker*);
 631
 632   void
 633   run(Workqueue*);
 634
 635   std::string
 636   get_name() const
 637   { return "Write_sections_task"; }
 638
 639  private:
 640   class Write_sections_locker;
 641
 642   const Layout* layout_;
 643   Output_file* of_;
 644   Task_token* output_sections_blocker_;
 645   Task_token* final_blocker_;
 646 };
 647
 648 // This task handles writing out data which is not part of a section
 649 // or segment.
 650
 651 class Write_data_task : public Task
 652 {
 653  public:
 654   Write_data_task(const Layout* layout, const Symbol_table* symtab,
 655                   Output_file* of, Task_token* final_blocker)
 656     : layout_(layout), symtab_(symtab), of_(of), final_blocker_(final_blocker)
 657   { }
 658
 659   // The standard Task methods.
 660
 661   Task_token*
 662   is_runnable();
 663
 664   void
 665   locks(Task_locker*);
 666
 667   void
 668   run(Workqueue*);
 669
 670   std::string
 671   get_name() const
 672   { return "Write_data_task"; }
 673
 674  private:
 675   const Layout* layout_;
 676   const Symbol_table* symtab_;
 677   Output_file* of_;
 678   Task_token* final_blocker_;
 679 };
 680
 681 // This task handles writing out the global symbols.
 682
 683 class Write_symbols_task : public Task
 684 {
 685  public:
 686   Write_symbols_task(const Symbol_table* symtab,
 687                      const Input_objects* input_objects,
 688                      const Stringpool* sympool, const Stringpool* dynpool,
 689                      Output_file* of, Task_token* final_blocker)
 690     : symtab_(symtab), input_objects_(input_objects), sympool_(sympool),
 691       dynpool_(dynpool), of_(of), final_blocker_(final_blocker)
 692   { }
 693
 694   // The standard Task methods.
 695
 696   Task_token*
 697   is_runnable();
 698
 699   void
 700   locks(Task_locker*);
 701
 702   void
 703   run(Workqueue*);
 704
 705   std::string
 706   get_name() const
 707   { return "Write_symbols_task"; }
 708
 709  private:
 710   const Symbol_table* symtab_;
 711   const Input_objects* input_objects_;
 712   const Stringpool* sympool_;
 713   const Stringpool* dynpool_;
 714   Output_file* of_;
 715   Task_token* final_blocker_;
 716 };
 717
 718 // This task handles writing out data in output sections which can't
 719 // be written out until all the input sections have been handled.
 720 // This is for sections whose contents is based on the contents of
 721 // other output sections.
 722
 723 class Write_after_input_sections_task : public Task
 724 {
 725  public:
 726   Write_after_input_sections_task(Layout* layout, Output_file* of,
 727                                   Task_token* input_sections_blocker,
 728                                   Task_token* final_blocker)
 729     : layout_(layout), of_(of),
 730       input_sections_blocker_(input_sections_blocker),
 731       final_blocker_(final_blocker)
 732   { }
 733
 734   // The standard Task methods.
 735
 736   Task_token*
 737   is_runnable();
 738
 739   void
 740   locks(Task_locker*);
 741
 742   void
 743   run(Workqueue*);
 744
 745   std::string
 746   get_name() const
 747   { return "Write_after_input_sections_task"; }
 748
 749  private:
 750   Layout* layout_;
 751   Output_file* of_;
 752   Task_token* input_sections_blocker_;
 753   Task_token* final_blocker_;
 754 };
 755
 756 // This task function handles closing the file.
 757
 758 class Close_task_runner : public Task_function_runner
 759 {
 760  public:
 761   Close_task_runner(const General_options* options, const Layout* layout,
 762                     Output_file* of)
 763     : options_(options), layout_(layout), of_(of)
 764   { }
 765
 766   // Run the operation.
 767   void
 768   run(Workqueue*, const Task*);
 769
 770  private:
 771   const General_options* options_;
 772   const Layout* layout_;
 773   Output_file* of_;
 774 };
 775
 776 // A small helper function to align an address.
 777
 778 inline uint64_t
 779 align_address(uint64_t address, uint64_t addralign)
 780 {
 781   if (addralign != 0)
 782     address = (address + addralign - 1) &~ (addralign - 1);
 783   return address;
 784 }
 785
 786 } // End namespace gold.
 787
 788 #endif // !defined(GOLD_LAYOUT_H)