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[thirdparty/binutils-gdb.git] / gold / output.cc
1 // output.cc -- manage the output file for gold
2
3 // Copyright 2006, 2007 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 <cstdlib>
26 #include <cerrno>
27 #include <fcntl.h>
28 #include <unistd.h>
29 #include <sys/mman.h>
30 #include <sys/stat.h>
31 #include <algorithm>
32 #include "libiberty.h" // for unlink_if_ordinary()
33
34 #include "parameters.h"
35 #include "object.h"
36 #include "symtab.h"
37 #include "reloc.h"
38 #include "merge.h"
39 #include "output.h"
40
41 namespace gold
42 {
43
44 // Output_data variables.
45
46 bool Output_data::sizes_are_fixed;
47
48 // Output_data methods.
49
50 Output_data::~Output_data()
51 {
52 }
53
54 // Set the address and offset.
55
56 void
57 Output_data::set_address(uint64_t addr, off_t off)
58 {
59 this->address_ = addr;
60 this->offset_ = off;
61
62 // Let the child class know.
63 this->do_set_address(addr, off);
64 }
65
66 // Return the default alignment for a size--32 or 64.
67
68 uint64_t
69 Output_data::default_alignment(int size)
70 {
71 if (size == 32)
72 return 4;
73 else if (size == 64)
74 return 8;
75 else
76 gold_unreachable();
77 }
78
79 // Output_section_header methods. This currently assumes that the
80 // segment and section lists are complete at construction time.
81
82 Output_section_headers::Output_section_headers(
83 const Layout* layout,
84 const Layout::Segment_list* segment_list,
85 const Layout::Section_list* unattached_section_list,
86 const Stringpool* secnamepool)
87 : layout_(layout),
88 segment_list_(segment_list),
89 unattached_section_list_(unattached_section_list),
90 secnamepool_(secnamepool)
91 {
92 // Count all the sections. Start with 1 for the null section.
93 off_t count = 1;
94 for (Layout::Segment_list::const_iterator p = segment_list->begin();
95 p != segment_list->end();
96 ++p)
97 if ((*p)->type() == elfcpp::PT_LOAD)
98 count += (*p)->output_section_count();
99 count += unattached_section_list->size();
100
101 const int size = parameters->get_size();
102 int shdr_size;
103 if (size == 32)
104 shdr_size = elfcpp::Elf_sizes<32>::shdr_size;
105 else if (size == 64)
106 shdr_size = elfcpp::Elf_sizes<64>::shdr_size;
107 else
108 gold_unreachable();
109
110 this->set_data_size(count * shdr_size);
111 }
112
113 // Write out the section headers.
114
115 void
116 Output_section_headers::do_write(Output_file* of)
117 {
118 if (parameters->get_size() == 32)
119 {
120 if (parameters->is_big_endian())
121 {
122 #ifdef HAVE_TARGET_32_BIG
123 this->do_sized_write<32, true>(of);
124 #else
125 gold_unreachable();
126 #endif
127 }
128 else
129 {
130 #ifdef HAVE_TARGET_32_LITTLE
131 this->do_sized_write<32, false>(of);
132 #else
133 gold_unreachable();
134 #endif
135 }
136 }
137 else if (parameters->get_size() == 64)
138 {
139 if (parameters->is_big_endian())
140 {
141 #ifdef HAVE_TARGET_64_BIG
142 this->do_sized_write<64, true>(of);
143 #else
144 gold_unreachable();
145 #endif
146 }
147 else
148 {
149 #ifdef HAVE_TARGET_64_LITTLE
150 this->do_sized_write<64, false>(of);
151 #else
152 gold_unreachable();
153 #endif
154 }
155 }
156 else
157 gold_unreachable();
158 }
159
160 template<int size, bool big_endian>
161 void
162 Output_section_headers::do_sized_write(Output_file* of)
163 {
164 off_t all_shdrs_size = this->data_size();
165 unsigned char* view = of->get_output_view(this->offset(), all_shdrs_size);
166
167 const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
168 unsigned char* v = view;
169
170 {
171 typename elfcpp::Shdr_write<size, big_endian> oshdr(v);
172 oshdr.put_sh_name(0);
173 oshdr.put_sh_type(elfcpp::SHT_NULL);
174 oshdr.put_sh_flags(0);
175 oshdr.put_sh_addr(0);
176 oshdr.put_sh_offset(0);
177 oshdr.put_sh_size(0);
178 oshdr.put_sh_link(0);
179 oshdr.put_sh_info(0);
180 oshdr.put_sh_addralign(0);
181 oshdr.put_sh_entsize(0);
182 }
183
184 v += shdr_size;
185
186 unsigned shndx = 1;
187 for (Layout::Segment_list::const_iterator p = this->segment_list_->begin();
188 p != this->segment_list_->end();
189 ++p)
190 v = (*p)->write_section_headers SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
191 this->layout_, this->secnamepool_, v, &shndx
192 SELECT_SIZE_ENDIAN(size, big_endian));
193 for (Layout::Section_list::const_iterator p =
194 this->unattached_section_list_->begin();
195 p != this->unattached_section_list_->end();
196 ++p)
197 {
198 gold_assert(shndx == (*p)->out_shndx());
199 elfcpp::Shdr_write<size, big_endian> oshdr(v);
200 (*p)->write_header(this->layout_, this->secnamepool_, &oshdr);
201 v += shdr_size;
202 ++shndx;
203 }
204
205 of->write_output_view(this->offset(), all_shdrs_size, view);
206 }
207
208 // Output_segment_header methods.
209
210 Output_segment_headers::Output_segment_headers(
211 const Layout::Segment_list& segment_list)
212 : segment_list_(segment_list)
213 {
214 const int size = parameters->get_size();
215 int phdr_size;
216 if (size == 32)
217 phdr_size = elfcpp::Elf_sizes<32>::phdr_size;
218 else if (size == 64)
219 phdr_size = elfcpp::Elf_sizes<64>::phdr_size;
220 else
221 gold_unreachable();
222
223 this->set_data_size(segment_list.size() * phdr_size);
224 }
225
226 void
227 Output_segment_headers::do_write(Output_file* of)
228 {
229 if (parameters->get_size() == 32)
230 {
231 if (parameters->is_big_endian())
232 {
233 #ifdef HAVE_TARGET_32_BIG
234 this->do_sized_write<32, true>(of);
235 #else
236 gold_unreachable();
237 #endif
238 }
239 else
240 {
241 #ifdef HAVE_TARGET_32_LITTLE
242 this->do_sized_write<32, false>(of);
243 #else
244 gold_unreachable();
245 #endif
246 }
247 }
248 else if (parameters->get_size() == 64)
249 {
250 if (parameters->is_big_endian())
251 {
252 #ifdef HAVE_TARGET_64_BIG
253 this->do_sized_write<64, true>(of);
254 #else
255 gold_unreachable();
256 #endif
257 }
258 else
259 {
260 #ifdef HAVE_TARGET_64_LITTLE
261 this->do_sized_write<64, false>(of);
262 #else
263 gold_unreachable();
264 #endif
265 }
266 }
267 else
268 gold_unreachable();
269 }
270
271 template<int size, bool big_endian>
272 void
273 Output_segment_headers::do_sized_write(Output_file* of)
274 {
275 const int phdr_size = elfcpp::Elf_sizes<size>::phdr_size;
276 off_t all_phdrs_size = this->segment_list_.size() * phdr_size;
277 unsigned char* view = of->get_output_view(this->offset(),
278 all_phdrs_size);
279 unsigned char* v = view;
280 for (Layout::Segment_list::const_iterator p = this->segment_list_.begin();
281 p != this->segment_list_.end();
282 ++p)
283 {
284 elfcpp::Phdr_write<size, big_endian> ophdr(v);
285 (*p)->write_header(&ophdr);
286 v += phdr_size;
287 }
288
289 of->write_output_view(this->offset(), all_phdrs_size, view);
290 }
291
292 // Output_file_header methods.
293
294 Output_file_header::Output_file_header(const Target* target,
295 const Symbol_table* symtab,
296 const Output_segment_headers* osh)
297 : target_(target),
298 symtab_(symtab),
299 segment_header_(osh),
300 section_header_(NULL),
301 shstrtab_(NULL)
302 {
303 const int size = parameters->get_size();
304 int ehdr_size;
305 if (size == 32)
306 ehdr_size = elfcpp::Elf_sizes<32>::ehdr_size;
307 else if (size == 64)
308 ehdr_size = elfcpp::Elf_sizes<64>::ehdr_size;
309 else
310 gold_unreachable();
311
312 this->set_data_size(ehdr_size);
313 }
314
315 // Set the section table information for a file header.
316
317 void
318 Output_file_header::set_section_info(const Output_section_headers* shdrs,
319 const Output_section* shstrtab)
320 {
321 this->section_header_ = shdrs;
322 this->shstrtab_ = shstrtab;
323 }
324
325 // Write out the file header.
326
327 void
328 Output_file_header::do_write(Output_file* of)
329 {
330 if (parameters->get_size() == 32)
331 {
332 if (parameters->is_big_endian())
333 {
334 #ifdef HAVE_TARGET_32_BIG
335 this->do_sized_write<32, true>(of);
336 #else
337 gold_unreachable();
338 #endif
339 }
340 else
341 {
342 #ifdef HAVE_TARGET_32_LITTLE
343 this->do_sized_write<32, false>(of);
344 #else
345 gold_unreachable();
346 #endif
347 }
348 }
349 else if (parameters->get_size() == 64)
350 {
351 if (parameters->is_big_endian())
352 {
353 #ifdef HAVE_TARGET_64_BIG
354 this->do_sized_write<64, true>(of);
355 #else
356 gold_unreachable();
357 #endif
358 }
359 else
360 {
361 #ifdef HAVE_TARGET_64_LITTLE
362 this->do_sized_write<64, false>(of);
363 #else
364 gold_unreachable();
365 #endif
366 }
367 }
368 else
369 gold_unreachable();
370 }
371
372 // Write out the file header with appropriate size and endianess.
373
374 template<int size, bool big_endian>
375 void
376 Output_file_header::do_sized_write(Output_file* of)
377 {
378 gold_assert(this->offset() == 0);
379
380 int ehdr_size = elfcpp::Elf_sizes<size>::ehdr_size;
381 unsigned char* view = of->get_output_view(0, ehdr_size);
382 elfcpp::Ehdr_write<size, big_endian> oehdr(view);
383
384 unsigned char e_ident[elfcpp::EI_NIDENT];
385 memset(e_ident, 0, elfcpp::EI_NIDENT);
386 e_ident[elfcpp::EI_MAG0] = elfcpp::ELFMAG0;
387 e_ident[elfcpp::EI_MAG1] = elfcpp::ELFMAG1;
388 e_ident[elfcpp::EI_MAG2] = elfcpp::ELFMAG2;
389 e_ident[elfcpp::EI_MAG3] = elfcpp::ELFMAG3;
390 if (size == 32)
391 e_ident[elfcpp::EI_CLASS] = elfcpp::ELFCLASS32;
392 else if (size == 64)
393 e_ident[elfcpp::EI_CLASS] = elfcpp::ELFCLASS64;
394 else
395 gold_unreachable();
396 e_ident[elfcpp::EI_DATA] = (big_endian
397 ? elfcpp::ELFDATA2MSB
398 : elfcpp::ELFDATA2LSB);
399 e_ident[elfcpp::EI_VERSION] = elfcpp::EV_CURRENT;
400 // FIXME: Some targets may need to set EI_OSABI and EI_ABIVERSION.
401 oehdr.put_e_ident(e_ident);
402
403 elfcpp::ET e_type;
404 if (parameters->output_is_object())
405 e_type = elfcpp::ET_REL;
406 else if (parameters->output_is_shared())
407 e_type = elfcpp::ET_DYN;
408 else
409 e_type = elfcpp::ET_EXEC;
410 oehdr.put_e_type(e_type);
411
412 oehdr.put_e_machine(this->target_->machine_code());
413 oehdr.put_e_version(elfcpp::EV_CURRENT);
414
415 // FIXME: Need to support -e, and target specific entry symbol.
416 Symbol* sym = this->symtab_->lookup("_start");
417 typename Sized_symbol<size>::Value_type v;
418 if (sym == NULL)
419 v = 0;
420 else
421 {
422 Sized_symbol<size>* ssym;
423 ssym = this->symtab_->get_sized_symbol SELECT_SIZE_NAME(size) (
424 sym SELECT_SIZE(size));
425 v = ssym->value();
426 }
427 oehdr.put_e_entry(v);
428
429 oehdr.put_e_phoff(this->segment_header_->offset());
430 oehdr.put_e_shoff(this->section_header_->offset());
431
432 // FIXME: The target needs to set the flags.
433 oehdr.put_e_flags(0);
434
435 oehdr.put_e_ehsize(elfcpp::Elf_sizes<size>::ehdr_size);
436 oehdr.put_e_phentsize(elfcpp::Elf_sizes<size>::phdr_size);
437 oehdr.put_e_phnum(this->segment_header_->data_size()
438 / elfcpp::Elf_sizes<size>::phdr_size);
439 oehdr.put_e_shentsize(elfcpp::Elf_sizes<size>::shdr_size);
440 oehdr.put_e_shnum(this->section_header_->data_size()
441 / elfcpp::Elf_sizes<size>::shdr_size);
442 oehdr.put_e_shstrndx(this->shstrtab_->out_shndx());
443
444 of->write_output_view(0, ehdr_size, view);
445 }
446
447 // Output_data_const methods.
448
449 void
450 Output_data_const::do_write(Output_file* of)
451 {
452 of->write(this->offset(), this->data_.data(), this->data_.size());
453 }
454
455 // Output_data_const_buffer methods.
456
457 void
458 Output_data_const_buffer::do_write(Output_file* of)
459 {
460 of->write(this->offset(), this->p_, this->data_size());
461 }
462
463 // Output_section_data methods.
464
465 // Record the output section, and set the entry size and such.
466
467 void
468 Output_section_data::set_output_section(Output_section* os)
469 {
470 gold_assert(this->output_section_ == NULL);
471 this->output_section_ = os;
472 this->do_adjust_output_section(os);
473 }
474
475 // Return the section index of the output section.
476
477 unsigned int
478 Output_section_data::do_out_shndx() const
479 {
480 gold_assert(this->output_section_ != NULL);
481 return this->output_section_->out_shndx();
482 }
483
484 // Output_data_strtab methods.
485
486 // Set the address. We don't actually care about the address, but we
487 // do set our final size.
488
489 void
490 Output_data_strtab::do_set_address(uint64_t, off_t)
491 {
492 this->strtab_->set_string_offsets();
493 this->set_data_size(this->strtab_->get_strtab_size());
494 }
495
496 // Write out a string table.
497
498 void
499 Output_data_strtab::do_write(Output_file* of)
500 {
501 this->strtab_->write(of, this->offset());
502 }
503
504 // Output_reloc methods.
505
506 // Get the symbol index of a relocation.
507
508 template<bool dynamic, int size, bool big_endian>
509 unsigned int
510 Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::get_symbol_index()
511 const
512 {
513 unsigned int index;
514 switch (this->local_sym_index_)
515 {
516 case INVALID_CODE:
517 gold_unreachable();
518
519 case GSYM_CODE:
520 if (this->u1_.gsym == NULL)
521 index = 0;
522 else if (dynamic)
523 index = this->u1_.gsym->dynsym_index();
524 else
525 index = this->u1_.gsym->symtab_index();
526 break;
527
528 case SECTION_CODE:
529 if (dynamic)
530 index = this->u1_.os->dynsym_index();
531 else
532 index = this->u1_.os->symtab_index();
533 break;
534
535 case 0:
536 // Relocations without symbols use a symbol index of 0.
537 index = 0;
538 break;
539
540 default:
541 if (dynamic)
542 {
543 // FIXME: It seems that some targets may need to generate
544 // dynamic relocations against local symbols for some
545 // reasons. This will have to be addressed at some point.
546 gold_unreachable();
547 }
548 else
549 index = this->u1_.relobj->symtab_index(this->local_sym_index_);
550 break;
551 }
552 gold_assert(index != -1U);
553 return index;
554 }
555
556 // Write out the offset and info fields of a Rel or Rela relocation
557 // entry.
558
559 template<bool dynamic, int size, bool big_endian>
560 template<typename Write_rel>
561 void
562 Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::write_rel(
563 Write_rel* wr) const
564 {
565 Address address = this->address_;
566 if (this->shndx_ != INVALID_CODE)
567 {
568 off_t off;
569 Output_section* os = this->u2_.relobj->output_section(this->shndx_,
570 &off);
571 gold_assert(os != NULL);
572 address += os->address() + off;
573 }
574 else if (this->u2_.od != NULL)
575 address += this->u2_.od->address();
576 wr->put_r_offset(address);
577 wr->put_r_info(elfcpp::elf_r_info<size>(this->get_symbol_index(),
578 this->type_));
579 }
580
581 // Write out a Rel relocation.
582
583 template<bool dynamic, int size, bool big_endian>
584 void
585 Output_reloc<elfcpp::SHT_REL, dynamic, size, big_endian>::write(
586 unsigned char* pov) const
587 {
588 elfcpp::Rel_write<size, big_endian> orel(pov);
589 this->write_rel(&orel);
590 }
591
592 // Write out a Rela relocation.
593
594 template<bool dynamic, int size, bool big_endian>
595 void
596 Output_reloc<elfcpp::SHT_RELA, dynamic, size, big_endian>::write(
597 unsigned char* pov) const
598 {
599 elfcpp::Rela_write<size, big_endian> orel(pov);
600 this->rel_.write_rel(&orel);
601 orel.put_r_addend(this->addend_);
602 }
603
604 // Output_data_reloc_base methods.
605
606 // Adjust the output section.
607
608 template<int sh_type, bool dynamic, int size, bool big_endian>
609 void
610 Output_data_reloc_base<sh_type, dynamic, size, big_endian>
611 ::do_adjust_output_section(Output_section* os)
612 {
613 if (sh_type == elfcpp::SHT_REL)
614 os->set_entsize(elfcpp::Elf_sizes<size>::rel_size);
615 else if (sh_type == elfcpp::SHT_RELA)
616 os->set_entsize(elfcpp::Elf_sizes<size>::rela_size);
617 else
618 gold_unreachable();
619 if (dynamic)
620 os->set_should_link_to_dynsym();
621 else
622 os->set_should_link_to_symtab();
623 }
624
625 // Write out relocation data.
626
627 template<int sh_type, bool dynamic, int size, bool big_endian>
628 void
629 Output_data_reloc_base<sh_type, dynamic, size, big_endian>::do_write(
630 Output_file* of)
631 {
632 const off_t off = this->offset();
633 const off_t oview_size = this->data_size();
634 unsigned char* const oview = of->get_output_view(off, oview_size);
635
636 unsigned char* pov = oview;
637 for (typename Relocs::const_iterator p = this->relocs_.begin();
638 p != this->relocs_.end();
639 ++p)
640 {
641 p->write(pov);
642 pov += reloc_size;
643 }
644
645 gold_assert(pov - oview == oview_size);
646
647 of->write_output_view(off, oview_size, oview);
648
649 // We no longer need the relocation entries.
650 this->relocs_.clear();
651 }
652
653 // Output_data_got::Got_entry methods.
654
655 // Write out the entry.
656
657 template<int size, bool big_endian>
658 void
659 Output_data_got<size, big_endian>::Got_entry::write(unsigned char* pov) const
660 {
661 Valtype val = 0;
662
663 switch (this->local_sym_index_)
664 {
665 case GSYM_CODE:
666 {
667 Symbol* gsym = this->u_.gsym;
668
669 // If the symbol is resolved locally, we need to write out its
670 // value. Otherwise we just write zero. The target code is
671 // responsible for creating a relocation entry to fill in the
672 // value at runtime.
673 if (gsym->final_value_is_known())
674 {
675 Sized_symbol<size>* sgsym;
676 // This cast is a bit ugly. We don't want to put a
677 // virtual method in Symbol, because we want Symbol to be
678 // as small as possible.
679 sgsym = static_cast<Sized_symbol<size>*>(gsym);
680 val = sgsym->value();
681 }
682 }
683 break;
684
685 case CONSTANT_CODE:
686 val = this->u_.constant;
687 break;
688
689 default:
690 val = this->u_.object->local_symbol_value(this->local_sym_index_);
691 break;
692 }
693
694 elfcpp::Swap<size, big_endian>::writeval(pov, val);
695 }
696
697 // Output_data_got methods.
698
699 // Add an entry for a global symbol to the GOT. This returns true if
700 // this is a new GOT entry, false if the symbol already had a GOT
701 // entry.
702
703 template<int size, bool big_endian>
704 bool
705 Output_data_got<size, big_endian>::add_global(Symbol* gsym)
706 {
707 if (gsym->has_got_offset())
708 return false;
709
710 this->entries_.push_back(Got_entry(gsym));
711 this->set_got_size();
712 gsym->set_got_offset(this->last_got_offset());
713 return true;
714 }
715
716 // Add an entry for a local symbol to the GOT. This returns true if
717 // this is a new GOT entry, false if the symbol already has a GOT
718 // entry.
719
720 template<int size, bool big_endian>
721 bool
722 Output_data_got<size, big_endian>::add_local(
723 Sized_relobj<size, big_endian>* object,
724 unsigned int symndx)
725 {
726 if (object->local_has_got_offset(symndx))
727 return false;
728 this->entries_.push_back(Got_entry(object, symndx));
729 this->set_got_size();
730 object->set_local_got_offset(symndx, this->last_got_offset());
731 return true;
732 }
733
734 // Write out the GOT.
735
736 template<int size, bool big_endian>
737 void
738 Output_data_got<size, big_endian>::do_write(Output_file* of)
739 {
740 const int add = size / 8;
741
742 const off_t off = this->offset();
743 const off_t oview_size = this->data_size();
744 unsigned char* const oview = of->get_output_view(off, oview_size);
745
746 unsigned char* pov = oview;
747 for (typename Got_entries::const_iterator p = this->entries_.begin();
748 p != this->entries_.end();
749 ++p)
750 {
751 p->write(pov);
752 pov += add;
753 }
754
755 gold_assert(pov - oview == oview_size);
756
757 of->write_output_view(off, oview_size, oview);
758
759 // We no longer need the GOT entries.
760 this->entries_.clear();
761 }
762
763 // Output_data_dynamic::Dynamic_entry methods.
764
765 // Write out the entry.
766
767 template<int size, bool big_endian>
768 void
769 Output_data_dynamic::Dynamic_entry::write(
770 unsigned char* pov,
771 const Stringpool* pool
772 ACCEPT_SIZE_ENDIAN) const
773 {
774 typename elfcpp::Elf_types<size>::Elf_WXword val;
775 switch (this->classification_)
776 {
777 case DYNAMIC_NUMBER:
778 val = this->u_.val;
779 break;
780
781 case DYNAMIC_SECTION_ADDRESS:
782 val = this->u_.od->address();
783 break;
784
785 case DYNAMIC_SECTION_SIZE:
786 val = this->u_.od->data_size();
787 break;
788
789 case DYNAMIC_SYMBOL:
790 {
791 const Sized_symbol<size>* s =
792 static_cast<const Sized_symbol<size>*>(this->u_.sym);
793 val = s->value();
794 }
795 break;
796
797 case DYNAMIC_STRING:
798 val = pool->get_offset(this->u_.str);
799 break;
800
801 default:
802 gold_unreachable();
803 }
804
805 elfcpp::Dyn_write<size, big_endian> dw(pov);
806 dw.put_d_tag(this->tag_);
807 dw.put_d_val(val);
808 }
809
810 // Output_data_dynamic methods.
811
812 // Adjust the output section to set the entry size.
813
814 void
815 Output_data_dynamic::do_adjust_output_section(Output_section* os)
816 {
817 if (parameters->get_size() == 32)
818 os->set_entsize(elfcpp::Elf_sizes<32>::dyn_size);
819 else if (parameters->get_size() == 64)
820 os->set_entsize(elfcpp::Elf_sizes<64>::dyn_size);
821 else
822 gold_unreachable();
823 }
824
825 // Set the final data size.
826
827 void
828 Output_data_dynamic::do_set_address(uint64_t, off_t)
829 {
830 // Add the terminating entry.
831 this->add_constant(elfcpp::DT_NULL, 0);
832
833 int dyn_size;
834 if (parameters->get_size() == 32)
835 dyn_size = elfcpp::Elf_sizes<32>::dyn_size;
836 else if (parameters->get_size() == 64)
837 dyn_size = elfcpp::Elf_sizes<64>::dyn_size;
838 else
839 gold_unreachable();
840 this->set_data_size(this->entries_.size() * dyn_size);
841 }
842
843 // Write out the dynamic entries.
844
845 void
846 Output_data_dynamic::do_write(Output_file* of)
847 {
848 if (parameters->get_size() == 32)
849 {
850 if (parameters->is_big_endian())
851 {
852 #ifdef HAVE_TARGET_32_BIG
853 this->sized_write<32, true>(of);
854 #else
855 gold_unreachable();
856 #endif
857 }
858 else
859 {
860 #ifdef HAVE_TARGET_32_LITTLE
861 this->sized_write<32, false>(of);
862 #else
863 gold_unreachable();
864 #endif
865 }
866 }
867 else if (parameters->get_size() == 64)
868 {
869 if (parameters->is_big_endian())
870 {
871 #ifdef HAVE_TARGET_64_BIG
872 this->sized_write<64, true>(of);
873 #else
874 gold_unreachable();
875 #endif
876 }
877 else
878 {
879 #ifdef HAVE_TARGET_64_LITTLE
880 this->sized_write<64, false>(of);
881 #else
882 gold_unreachable();
883 #endif
884 }
885 }
886 else
887 gold_unreachable();
888 }
889
890 template<int size, bool big_endian>
891 void
892 Output_data_dynamic::sized_write(Output_file* of)
893 {
894 const int dyn_size = elfcpp::Elf_sizes<size>::dyn_size;
895
896 const off_t offset = this->offset();
897 const off_t oview_size = this->data_size();
898 unsigned char* const oview = of->get_output_view(offset, oview_size);
899
900 unsigned char* pov = oview;
901 for (typename Dynamic_entries::const_iterator p = this->entries_.begin();
902 p != this->entries_.end();
903 ++p)
904 {
905 p->write SELECT_SIZE_ENDIAN_NAME(size, big_endian)(
906 pov, this->pool_ SELECT_SIZE_ENDIAN(size, big_endian));
907 pov += dyn_size;
908 }
909
910 gold_assert(pov - oview == oview_size);
911
912 of->write_output_view(offset, oview_size, oview);
913
914 // We no longer need the dynamic entries.
915 this->entries_.clear();
916 }
917
918 // Output_section::Input_section methods.
919
920 // Return the data size. For an input section we store the size here.
921 // For an Output_section_data, we have to ask it for the size.
922
923 off_t
924 Output_section::Input_section::data_size() const
925 {
926 if (this->is_input_section())
927 return this->u1_.data_size;
928 else
929 return this->u2_.posd->data_size();
930 }
931
932 // Set the address and file offset.
933
934 void
935 Output_section::Input_section::set_address(uint64_t addr, off_t off,
936 off_t secoff)
937 {
938 if (this->is_input_section())
939 this->u2_.object->set_section_offset(this->shndx_, off - secoff);
940 else
941 this->u2_.posd->set_address(addr, off);
942 }
943
944 // Try to turn an input address into an output address.
945
946 bool
947 Output_section::Input_section::output_address(const Relobj* object,
948 unsigned int shndx,
949 off_t offset,
950 uint64_t output_section_address,
951 uint64_t *poutput) const
952 {
953 if (!this->is_input_section())
954 return this->u2_.posd->output_address(object, shndx, offset,
955 output_section_address, poutput);
956 else
957 {
958 if (this->shndx_ != shndx
959 || this->u2_.object != object)
960 return false;
961 off_t output_offset;
962 Output_section* os = object->output_section(shndx, &output_offset);
963 gold_assert(os != NULL);
964 *poutput = output_section_address + output_offset + offset;
965 return true;
966 }
967 }
968
969 // Write out the data. We don't have to do anything for an input
970 // section--they are handled via Object::relocate--but this is where
971 // we write out the data for an Output_section_data.
972
973 void
974 Output_section::Input_section::write(Output_file* of)
975 {
976 if (!this->is_input_section())
977 this->u2_.posd->write(of);
978 }
979
980 // Output_section methods.
981
982 // Construct an Output_section. NAME will point into a Stringpool.
983
984 Output_section::Output_section(const char* name, elfcpp::Elf_Word type,
985 elfcpp::Elf_Xword flags)
986 : name_(name),
987 addralign_(0),
988 entsize_(0),
989 link_section_(NULL),
990 link_(0),
991 info_section_(NULL),
992 info_(0),
993 type_(type),
994 flags_(flags),
995 out_shndx_(0),
996 symtab_index_(0),
997 dynsym_index_(0),
998 input_sections_(),
999 first_input_offset_(0),
1000 fills_(),
1001 needs_symtab_index_(false),
1002 needs_dynsym_index_(false),
1003 should_link_to_symtab_(false),
1004 should_link_to_dynsym_(false)
1005 {
1006 }
1007
1008 Output_section::~Output_section()
1009 {
1010 }
1011
1012 // Set the entry size.
1013
1014 void
1015 Output_section::set_entsize(uint64_t v)
1016 {
1017 if (this->entsize_ == 0)
1018 this->entsize_ = v;
1019 else
1020 gold_assert(this->entsize_ == v);
1021 }
1022
1023 // Add the input section SHNDX, with header SHDR, named SECNAME, in
1024 // OBJECT, to the Output_section. Return the offset of the input
1025 // section within the output section. We don't always keep track of
1026 // input sections for an Output_section. Instead, each Object keeps
1027 // track of the Output_section for each of its input sections.
1028
1029 template<int size, bool big_endian>
1030 off_t
1031 Output_section::add_input_section(Relobj* object, unsigned int shndx,
1032 const char* secname,
1033 const elfcpp::Shdr<size, big_endian>& shdr)
1034 {
1035 elfcpp::Elf_Xword addralign = shdr.get_sh_addralign();
1036 if ((addralign & (addralign - 1)) != 0)
1037 {
1038 object->error(_("invalid alignment %lu for section \"%s\""),
1039 static_cast<unsigned long>(addralign), secname);
1040 addralign = 1;
1041 }
1042
1043 if (addralign > this->addralign_)
1044 this->addralign_ = addralign;
1045
1046 // If this is a SHF_MERGE section, we pass all the input sections to
1047 // a Output_data_merge.
1048 if ((shdr.get_sh_flags() & elfcpp::SHF_MERGE) != 0)
1049 {
1050 if (this->add_merge_input_section(object, shndx, shdr.get_sh_flags(),
1051 shdr.get_sh_entsize(),
1052 addralign))
1053 {
1054 // Tell the relocation routines that they need to call the
1055 // output_address method to determine the final address.
1056 return -1;
1057 }
1058 }
1059
1060 off_t offset_in_section = this->data_size();
1061 off_t aligned_offset_in_section = align_address(offset_in_section,
1062 addralign);
1063
1064 if (aligned_offset_in_section > offset_in_section
1065 && (shdr.get_sh_flags() & elfcpp::SHF_EXECINSTR) != 0
1066 && object->target()->has_code_fill())
1067 {
1068 // We need to add some fill data. Using fill_list_ when
1069 // possible is an optimization, since we will often have fill
1070 // sections without input sections.
1071 off_t fill_len = aligned_offset_in_section - offset_in_section;
1072 if (this->input_sections_.empty())
1073 this->fills_.push_back(Fill(offset_in_section, fill_len));
1074 else
1075 {
1076 // FIXME: When relaxing, the size needs to adjust to
1077 // maintain a constant alignment.
1078 std::string fill_data(object->target()->code_fill(fill_len));
1079 Output_data_const* odc = new Output_data_const(fill_data, 1);
1080 this->input_sections_.push_back(Input_section(odc));
1081 }
1082 }
1083
1084 this->set_data_size(aligned_offset_in_section + shdr.get_sh_size());
1085
1086 // We need to keep track of this section if we are already keeping
1087 // track of sections, or if we are relaxing. FIXME: Add test for
1088 // relaxing.
1089 if (!this->input_sections_.empty())
1090 this->input_sections_.push_back(Input_section(object, shndx,
1091 shdr.get_sh_size(),
1092 addralign));
1093
1094 return aligned_offset_in_section;
1095 }
1096
1097 // Add arbitrary data to an output section.
1098
1099 void
1100 Output_section::add_output_section_data(Output_section_data* posd)
1101 {
1102 Input_section inp(posd);
1103 this->add_output_section_data(&inp);
1104 }
1105
1106 // Add arbitrary data to an output section by Input_section.
1107
1108 void
1109 Output_section::add_output_section_data(Input_section* inp)
1110 {
1111 if (this->input_sections_.empty())
1112 this->first_input_offset_ = this->data_size();
1113
1114 this->input_sections_.push_back(*inp);
1115
1116 uint64_t addralign = inp->addralign();
1117 if (addralign > this->addralign_)
1118 this->addralign_ = addralign;
1119
1120 inp->set_output_section(this);
1121 }
1122
1123 // Add a merge section to an output section.
1124
1125 void
1126 Output_section::add_output_merge_section(Output_section_data* posd,
1127 bool is_string, uint64_t entsize)
1128 {
1129 Input_section inp(posd, is_string, entsize);
1130 this->add_output_section_data(&inp);
1131 }
1132
1133 // Add an input section to a SHF_MERGE section.
1134
1135 bool
1136 Output_section::add_merge_input_section(Relobj* object, unsigned int shndx,
1137 uint64_t flags, uint64_t entsize,
1138 uint64_t addralign)
1139 {
1140 // We only merge constants if the alignment is not more than the
1141 // entry size. This could be handled, but it's unusual.
1142 if (addralign > entsize)
1143 return false;
1144
1145 bool is_string = (flags & elfcpp::SHF_STRINGS) != 0;
1146 Input_section_list::iterator p;
1147 for (p = this->input_sections_.begin();
1148 p != this->input_sections_.end();
1149 ++p)
1150 if (p->is_merge_section(is_string, entsize))
1151 break;
1152
1153 // We handle the actual constant merging in Output_merge_data or
1154 // Output_merge_string_data.
1155 if (p != this->input_sections_.end())
1156 p->add_input_section(object, shndx);
1157 else
1158 {
1159 Output_section_data* posd;
1160 if (!is_string)
1161 posd = new Output_merge_data(entsize);
1162 else if (entsize == 1)
1163 posd = new Output_merge_string<char>();
1164 else if (entsize == 2)
1165 posd = new Output_merge_string<uint16_t>();
1166 else if (entsize == 4)
1167 posd = new Output_merge_string<uint32_t>();
1168 else
1169 return false;
1170
1171 this->add_output_merge_section(posd, is_string, entsize);
1172 posd->add_input_section(object, shndx);
1173 }
1174
1175 return true;
1176 }
1177
1178 // Return the output virtual address of OFFSET relative to the start
1179 // of input section SHNDX in object OBJECT.
1180
1181 uint64_t
1182 Output_section::output_address(const Relobj* object, unsigned int shndx,
1183 off_t offset) const
1184 {
1185 uint64_t addr = this->address() + this->first_input_offset_;
1186 for (Input_section_list::const_iterator p = this->input_sections_.begin();
1187 p != this->input_sections_.end();
1188 ++p)
1189 {
1190 addr = align_address(addr, p->addralign());
1191 uint64_t output;
1192 if (p->output_address(object, shndx, offset, addr, &output))
1193 return output;
1194 addr += p->data_size();
1195 }
1196
1197 // If we get here, it means that we don't know the mapping for this
1198 // input section. This might happen in principle if
1199 // add_input_section were called before add_output_section_data.
1200 // But it should never actually happen.
1201
1202 gold_unreachable();
1203 }
1204
1205 // Set the address of an Output_section. This is where we handle
1206 // setting the addresses of any Output_section_data objects.
1207
1208 void
1209 Output_section::do_set_address(uint64_t address, off_t startoff)
1210 {
1211 if (this->input_sections_.empty())
1212 return;
1213
1214 off_t off = startoff + this->first_input_offset_;
1215 for (Input_section_list::iterator p = this->input_sections_.begin();
1216 p != this->input_sections_.end();
1217 ++p)
1218 {
1219 off = align_address(off, p->addralign());
1220 p->set_address(address + (off - startoff), off, startoff);
1221 off += p->data_size();
1222 }
1223
1224 this->set_data_size(off - startoff);
1225 }
1226
1227 // Write the section header to *OSHDR.
1228
1229 template<int size, bool big_endian>
1230 void
1231 Output_section::write_header(const Layout* layout,
1232 const Stringpool* secnamepool,
1233 elfcpp::Shdr_write<size, big_endian>* oshdr) const
1234 {
1235 oshdr->put_sh_name(secnamepool->get_offset(this->name_));
1236 oshdr->put_sh_type(this->type_);
1237 oshdr->put_sh_flags(this->flags_);
1238 oshdr->put_sh_addr(this->address());
1239 oshdr->put_sh_offset(this->offset());
1240 oshdr->put_sh_size(this->data_size());
1241 if (this->link_section_ != NULL)
1242 oshdr->put_sh_link(this->link_section_->out_shndx());
1243 else if (this->should_link_to_symtab_)
1244 oshdr->put_sh_link(layout->symtab_section()->out_shndx());
1245 else if (this->should_link_to_dynsym_)
1246 oshdr->put_sh_link(layout->dynsym_section()->out_shndx());
1247 else
1248 oshdr->put_sh_link(this->link_);
1249 if (this->info_section_ != NULL)
1250 oshdr->put_sh_info(this->info_section_->out_shndx());
1251 else
1252 oshdr->put_sh_info(this->info_);
1253 oshdr->put_sh_addralign(this->addralign_);
1254 oshdr->put_sh_entsize(this->entsize_);
1255 }
1256
1257 // Write out the data. For input sections the data is written out by
1258 // Object::relocate, but we have to handle Output_section_data objects
1259 // here.
1260
1261 void
1262 Output_section::do_write(Output_file* of)
1263 {
1264 off_t output_section_file_offset = this->offset();
1265 for (Fill_list::iterator p = this->fills_.begin();
1266 p != this->fills_.end();
1267 ++p)
1268 {
1269 std::string fill_data(of->target()->code_fill(p->length()));
1270 of->write(output_section_file_offset + p->section_offset(),
1271 fill_data.data(), fill_data.size());
1272 }
1273
1274 for (Input_section_list::iterator p = this->input_sections_.begin();
1275 p != this->input_sections_.end();
1276 ++p)
1277 p->write(of);
1278 }
1279
1280 // Output segment methods.
1281
1282 Output_segment::Output_segment(elfcpp::Elf_Word type, elfcpp::Elf_Word flags)
1283 : output_data_(),
1284 output_bss_(),
1285 vaddr_(0),
1286 paddr_(0),
1287 memsz_(0),
1288 align_(0),
1289 offset_(0),
1290 filesz_(0),
1291 type_(type),
1292 flags_(flags),
1293 is_align_known_(false)
1294 {
1295 }
1296
1297 // Add an Output_section to an Output_segment.
1298
1299 void
1300 Output_segment::add_output_section(Output_section* os,
1301 elfcpp::Elf_Word seg_flags,
1302 bool front)
1303 {
1304 gold_assert((os->flags() & elfcpp::SHF_ALLOC) != 0);
1305 gold_assert(!this->is_align_known_);
1306
1307 // Update the segment flags.
1308 this->flags_ |= seg_flags;
1309
1310 Output_segment::Output_data_list* pdl;
1311 if (os->type() == elfcpp::SHT_NOBITS)
1312 pdl = &this->output_bss_;
1313 else
1314 pdl = &this->output_data_;
1315
1316 // So that PT_NOTE segments will work correctly, we need to ensure
1317 // that all SHT_NOTE sections are adjacent. This will normally
1318 // happen automatically, because all the SHT_NOTE input sections
1319 // will wind up in the same output section. However, it is possible
1320 // for multiple SHT_NOTE input sections to have different section
1321 // flags, and thus be in different output sections, but for the
1322 // different section flags to map into the same segment flags and
1323 // thus the same output segment.
1324
1325 // Note that while there may be many input sections in an output
1326 // section, there are normally only a few output sections in an
1327 // output segment. This loop is expected to be fast.
1328
1329 if (os->type() == elfcpp::SHT_NOTE && !pdl->empty())
1330 {
1331 Output_segment::Output_data_list::iterator p = pdl->end();
1332 do
1333 {
1334 --p;
1335 if ((*p)->is_section_type(elfcpp::SHT_NOTE))
1336 {
1337 // We don't worry about the FRONT parameter.
1338 ++p;
1339 pdl->insert(p, os);
1340 return;
1341 }
1342 }
1343 while (p != pdl->begin());
1344 }
1345
1346 // Similarly, so that PT_TLS segments will work, we need to group
1347 // SHF_TLS sections. An SHF_TLS/SHT_NOBITS section is a special
1348 // case: we group the SHF_TLS/SHT_NOBITS sections right after the
1349 // SHF_TLS/SHT_PROGBITS sections. This lets us set up PT_TLS
1350 // correctly.
1351 if ((os->flags() & elfcpp::SHF_TLS) != 0 && !this->output_data_.empty())
1352 {
1353 pdl = &this->output_data_;
1354 bool nobits = os->type() == elfcpp::SHT_NOBITS;
1355 bool sawtls = false;
1356 Output_segment::Output_data_list::iterator p = pdl->end();
1357 do
1358 {
1359 --p;
1360 bool insert;
1361 if ((*p)->is_section_flag_set(elfcpp::SHF_TLS))
1362 {
1363 sawtls = true;
1364 // Put a NOBITS section after the first TLS section.
1365 // But a PROGBITS section after the first TLS/PROGBITS
1366 // section.
1367 insert = nobits || !(*p)->is_section_type(elfcpp::SHT_NOBITS);
1368 }
1369 else
1370 {
1371 // If we've gone past the TLS sections, but we've seen a
1372 // TLS section, then we need to insert this section now.
1373 insert = sawtls;
1374 }
1375
1376 if (insert)
1377 {
1378 // We don't worry about the FRONT parameter.
1379 ++p;
1380 pdl->insert(p, os);
1381 return;
1382 }
1383 }
1384 while (p != pdl->begin());
1385
1386 // There are no TLS sections yet; put this one at the requested
1387 // location in the section list.
1388 }
1389
1390 if (front)
1391 pdl->push_front(os);
1392 else
1393 pdl->push_back(os);
1394 }
1395
1396 // Add an Output_data (which is not an Output_section) to the start of
1397 // a segment.
1398
1399 void
1400 Output_segment::add_initial_output_data(Output_data* od)
1401 {
1402 gold_assert(!this->is_align_known_);
1403 this->output_data_.push_front(od);
1404 }
1405
1406 // Return the maximum alignment of the Output_data in Output_segment.
1407 // Once we compute this, we prohibit new sections from being added.
1408
1409 uint64_t
1410 Output_segment::addralign()
1411 {
1412 if (!this->is_align_known_)
1413 {
1414 uint64_t addralign;
1415
1416 addralign = Output_segment::maximum_alignment(&this->output_data_);
1417 if (addralign > this->align_)
1418 this->align_ = addralign;
1419
1420 addralign = Output_segment::maximum_alignment(&this->output_bss_);
1421 if (addralign > this->align_)
1422 this->align_ = addralign;
1423
1424 this->is_align_known_ = true;
1425 }
1426
1427 return this->align_;
1428 }
1429
1430 // Return the maximum alignment of a list of Output_data.
1431
1432 uint64_t
1433 Output_segment::maximum_alignment(const Output_data_list* pdl)
1434 {
1435 uint64_t ret = 0;
1436 for (Output_data_list::const_iterator p = pdl->begin();
1437 p != pdl->end();
1438 ++p)
1439 {
1440 uint64_t addralign = (*p)->addralign();
1441 if (addralign > ret)
1442 ret = addralign;
1443 }
1444 return ret;
1445 }
1446
1447 // Set the section addresses for an Output_segment. ADDR is the
1448 // address and *POFF is the file offset. Set the section indexes
1449 // starting with *PSHNDX. Return the address of the immediately
1450 // following segment. Update *POFF and *PSHNDX.
1451
1452 uint64_t
1453 Output_segment::set_section_addresses(uint64_t addr, off_t* poff,
1454 unsigned int* pshndx)
1455 {
1456 gold_assert(this->type_ == elfcpp::PT_LOAD);
1457
1458 this->vaddr_ = addr;
1459 this->paddr_ = addr;
1460
1461 off_t orig_off = *poff;
1462 this->offset_ = orig_off;
1463
1464 *poff = align_address(*poff, this->addralign());
1465
1466 addr = this->set_section_list_addresses(&this->output_data_, addr, poff,
1467 pshndx);
1468 this->filesz_ = *poff - orig_off;
1469
1470 off_t off = *poff;
1471
1472 uint64_t ret = this->set_section_list_addresses(&this->output_bss_, addr,
1473 poff, pshndx);
1474 this->memsz_ = *poff - orig_off;
1475
1476 // Ignore the file offset adjustments made by the BSS Output_data
1477 // objects.
1478 *poff = off;
1479
1480 return ret;
1481 }
1482
1483 // Set the addresses and file offsets in a list of Output_data
1484 // structures.
1485
1486 uint64_t
1487 Output_segment::set_section_list_addresses(Output_data_list* pdl,
1488 uint64_t addr, off_t* poff,
1489 unsigned int* pshndx)
1490 {
1491 off_t startoff = *poff;
1492
1493 off_t off = startoff;
1494 for (Output_data_list::iterator p = pdl->begin();
1495 p != pdl->end();
1496 ++p)
1497 {
1498 off = align_address(off, (*p)->addralign());
1499 (*p)->set_address(addr + (off - startoff), off);
1500
1501 // Unless this is a PT_TLS segment, we want to ignore the size
1502 // of a SHF_TLS/SHT_NOBITS section. Such a section does not
1503 // affect the size of a PT_LOAD segment.
1504 if (this->type_ == elfcpp::PT_TLS
1505 || !(*p)->is_section_flag_set(elfcpp::SHF_TLS)
1506 || !(*p)->is_section_type(elfcpp::SHT_NOBITS))
1507 off += (*p)->data_size();
1508
1509 if ((*p)->is_section())
1510 {
1511 (*p)->set_out_shndx(*pshndx);
1512 ++*pshndx;
1513 }
1514 }
1515
1516 *poff = off;
1517 return addr + (off - startoff);
1518 }
1519
1520 // For a non-PT_LOAD segment, set the offset from the sections, if
1521 // any.
1522
1523 void
1524 Output_segment::set_offset()
1525 {
1526 gold_assert(this->type_ != elfcpp::PT_LOAD);
1527
1528 if (this->output_data_.empty() && this->output_bss_.empty())
1529 {
1530 this->vaddr_ = 0;
1531 this->paddr_ = 0;
1532 this->memsz_ = 0;
1533 this->align_ = 0;
1534 this->offset_ = 0;
1535 this->filesz_ = 0;
1536 return;
1537 }
1538
1539 const Output_data* first;
1540 if (this->output_data_.empty())
1541 first = this->output_bss_.front();
1542 else
1543 first = this->output_data_.front();
1544 this->vaddr_ = first->address();
1545 this->paddr_ = this->vaddr_;
1546 this->offset_ = first->offset();
1547
1548 if (this->output_data_.empty())
1549 this->filesz_ = 0;
1550 else
1551 {
1552 const Output_data* last_data = this->output_data_.back();
1553 this->filesz_ = (last_data->address()
1554 + last_data->data_size()
1555 - this->vaddr_);
1556 }
1557
1558 const Output_data* last;
1559 if (this->output_bss_.empty())
1560 last = this->output_data_.back();
1561 else
1562 last = this->output_bss_.back();
1563 this->memsz_ = (last->address()
1564 + last->data_size()
1565 - this->vaddr_);
1566 }
1567
1568 // Return the number of Output_sections in an Output_segment.
1569
1570 unsigned int
1571 Output_segment::output_section_count() const
1572 {
1573 return (this->output_section_count_list(&this->output_data_)
1574 + this->output_section_count_list(&this->output_bss_));
1575 }
1576
1577 // Return the number of Output_sections in an Output_data_list.
1578
1579 unsigned int
1580 Output_segment::output_section_count_list(const Output_data_list* pdl) const
1581 {
1582 unsigned int count = 0;
1583 for (Output_data_list::const_iterator p = pdl->begin();
1584 p != pdl->end();
1585 ++p)
1586 {
1587 if ((*p)->is_section())
1588 ++count;
1589 }
1590 return count;
1591 }
1592
1593 // Write the segment data into *OPHDR.
1594
1595 template<int size, bool big_endian>
1596 void
1597 Output_segment::write_header(elfcpp::Phdr_write<size, big_endian>* ophdr)
1598 {
1599 ophdr->put_p_type(this->type_);
1600 ophdr->put_p_offset(this->offset_);
1601 ophdr->put_p_vaddr(this->vaddr_);
1602 ophdr->put_p_paddr(this->paddr_);
1603 ophdr->put_p_filesz(this->filesz_);
1604 ophdr->put_p_memsz(this->memsz_);
1605 ophdr->put_p_flags(this->flags_);
1606 ophdr->put_p_align(this->addralign());
1607 }
1608
1609 // Write the section headers into V.
1610
1611 template<int size, bool big_endian>
1612 unsigned char*
1613 Output_segment::write_section_headers(const Layout* layout,
1614 const Stringpool* secnamepool,
1615 unsigned char* v,
1616 unsigned int *pshndx
1617 ACCEPT_SIZE_ENDIAN) const
1618 {
1619 // Every section that is attached to a segment must be attached to a
1620 // PT_LOAD segment, so we only write out section headers for PT_LOAD
1621 // segments.
1622 if (this->type_ != elfcpp::PT_LOAD)
1623 return v;
1624
1625 v = this->write_section_headers_list
1626 SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
1627 layout, secnamepool, &this->output_data_, v, pshndx
1628 SELECT_SIZE_ENDIAN(size, big_endian));
1629 v = this->write_section_headers_list
1630 SELECT_SIZE_ENDIAN_NAME(size, big_endian) (
1631 layout, secnamepool, &this->output_bss_, v, pshndx
1632 SELECT_SIZE_ENDIAN(size, big_endian));
1633 return v;
1634 }
1635
1636 template<int size, bool big_endian>
1637 unsigned char*
1638 Output_segment::write_section_headers_list(const Layout* layout,
1639 const Stringpool* secnamepool,
1640 const Output_data_list* pdl,
1641 unsigned char* v,
1642 unsigned int* pshndx
1643 ACCEPT_SIZE_ENDIAN) const
1644 {
1645 const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
1646 for (Output_data_list::const_iterator p = pdl->begin();
1647 p != pdl->end();
1648 ++p)
1649 {
1650 if ((*p)->is_section())
1651 {
1652 const Output_section* ps = static_cast<const Output_section*>(*p);
1653 gold_assert(*pshndx == ps->out_shndx());
1654 elfcpp::Shdr_write<size, big_endian> oshdr(v);
1655 ps->write_header(layout, secnamepool, &oshdr);
1656 v += shdr_size;
1657 ++*pshndx;
1658 }
1659 }
1660 return v;
1661 }
1662
1663 // Output_file methods.
1664
1665 Output_file::Output_file(const General_options& options, Target* target)
1666 : options_(options),
1667 target_(target),
1668 name_(options.output_file_name()),
1669 o_(-1),
1670 file_size_(0),
1671 base_(NULL)
1672 {
1673 }
1674
1675 // Open the output file.
1676
1677 void
1678 Output_file::open(off_t file_size)
1679 {
1680 this->file_size_ = file_size;
1681
1682 // Unlink the file first; otherwise the open() may fail if the file
1683 // is busy (e.g. it's an executable that's currently being executed).
1684 //
1685 // However, the linker may be part of a system where a zero-length
1686 // file is created for it to write to, with tight permissions (gcc
1687 // 2.95 did something like this). Unlinking the file would work
1688 // around those permission controls, so we only unlink if the file
1689 // has a non-zero size. We also unlink only regular files to avoid
1690 // trouble with directories/etc.
1691 //
1692 // If we fail, continue; this command is merely a best-effort attempt
1693 // to improve the odds for open().
1694
1695 struct stat s;
1696 if (::stat(this->name_, &s) == 0 && s.st_size != 0)
1697 unlink_if_ordinary(this->name_);
1698
1699 int mode = parameters->output_is_object() ? 0666 : 0777;
1700 int o = ::open(this->name_, O_RDWR | O_CREAT | O_TRUNC, mode);
1701 if (o < 0)
1702 gold_fatal(_("%s: open: %s"), this->name_, strerror(errno));
1703 this->o_ = o;
1704
1705 // Write out one byte to make the file the right size.
1706 if (::lseek(o, file_size - 1, SEEK_SET) < 0)
1707 gold_fatal(_("%s: lseek: %s"), this->name_, strerror(errno));
1708 char b = 0;
1709 if (::write(o, &b, 1) != 1)
1710 gold_fatal(_("%s: write: %s"), this->name_, strerror(errno));
1711
1712 // Map the file into memory.
1713 void* base = ::mmap(NULL, file_size, PROT_READ | PROT_WRITE,
1714 MAP_SHARED, o, 0);
1715 if (base == MAP_FAILED)
1716 gold_fatal(_("%s: mmap: %s"), this->name_, strerror(errno));
1717 this->base_ = static_cast<unsigned char*>(base);
1718 }
1719
1720 // Close the output file.
1721
1722 void
1723 Output_file::close()
1724 {
1725 if (::munmap(this->base_, this->file_size_) < 0)
1726 gold_error(_("%s: munmap: %s"), this->name_, strerror(errno));
1727 this->base_ = NULL;
1728
1729 if (::close(this->o_) < 0)
1730 gold_error(_("%s: close: %s"), this->name_, strerror(errno));
1731 this->o_ = -1;
1732 }
1733
1734 // Instantiate the templates we need. We could use the configure
1735 // script to restrict this to only the ones for implemented targets.
1736
1737 #ifdef HAVE_TARGET_32_LITTLE
1738 template
1739 off_t
1740 Output_section::add_input_section<32, false>(
1741 Relobj* object,
1742 unsigned int shndx,
1743 const char* secname,
1744 const elfcpp::Shdr<32, false>& shdr);
1745 #endif
1746
1747 #ifdef HAVE_TARGET_32_BIG
1748 template
1749 off_t
1750 Output_section::add_input_section<32, true>(
1751 Relobj* object,
1752 unsigned int shndx,
1753 const char* secname,
1754 const elfcpp::Shdr<32, true>& shdr);
1755 #endif
1756
1757 #ifdef HAVE_TARGET_64_LITTLE
1758 template
1759 off_t
1760 Output_section::add_input_section<64, false>(
1761 Relobj* object,
1762 unsigned int shndx,
1763 const char* secname,
1764 const elfcpp::Shdr<64, false>& shdr);
1765 #endif
1766
1767 #ifdef HAVE_TARGET_64_BIG
1768 template
1769 off_t
1770 Output_section::add_input_section<64, true>(
1771 Relobj* object,
1772 unsigned int shndx,
1773 const char* secname,
1774 const elfcpp::Shdr<64, true>& shdr);
1775 #endif
1776
1777 #ifdef HAVE_TARGET_32_LITTLE
1778 template
1779 class Output_data_reloc<elfcpp::SHT_REL, false, 32, false>;
1780 #endif
1781
1782 #ifdef HAVE_TARGET_32_BIG
1783 template
1784 class Output_data_reloc<elfcpp::SHT_REL, false, 32, true>;
1785 #endif
1786
1787 #ifdef HAVE_TARGET_64_LITTLE
1788 template
1789 class Output_data_reloc<elfcpp::SHT_REL, false, 64, false>;
1790 #endif
1791
1792 #ifdef HAVE_TARGET_64_BIG
1793 template
1794 class Output_data_reloc<elfcpp::SHT_REL, false, 64, true>;
1795 #endif
1796
1797 #ifdef HAVE_TARGET_32_LITTLE
1798 template
1799 class Output_data_reloc<elfcpp::SHT_REL, true, 32, false>;
1800 #endif
1801
1802 #ifdef HAVE_TARGET_32_BIG
1803 template
1804 class Output_data_reloc<elfcpp::SHT_REL, true, 32, true>;
1805 #endif
1806
1807 #ifdef HAVE_TARGET_64_LITTLE
1808 template
1809 class Output_data_reloc<elfcpp::SHT_REL, true, 64, false>;
1810 #endif
1811
1812 #ifdef HAVE_TARGET_64_BIG
1813 template
1814 class Output_data_reloc<elfcpp::SHT_REL, true, 64, true>;
1815 #endif
1816
1817 #ifdef HAVE_TARGET_32_LITTLE
1818 template
1819 class Output_data_reloc<elfcpp::SHT_RELA, false, 32, false>;
1820 #endif
1821
1822 #ifdef HAVE_TARGET_32_BIG
1823 template
1824 class Output_data_reloc<elfcpp::SHT_RELA, false, 32, true>;
1825 #endif
1826
1827 #ifdef HAVE_TARGET_64_LITTLE
1828 template
1829 class Output_data_reloc<elfcpp::SHT_RELA, false, 64, false>;
1830 #endif
1831
1832 #ifdef HAVE_TARGET_64_BIG
1833 template
1834 class Output_data_reloc<elfcpp::SHT_RELA, false, 64, true>;
1835 #endif
1836
1837 #ifdef HAVE_TARGET_32_LITTLE
1838 template
1839 class Output_data_reloc<elfcpp::SHT_RELA, true, 32, false>;
1840 #endif
1841
1842 #ifdef HAVE_TARGET_32_BIG
1843 template
1844 class Output_data_reloc<elfcpp::SHT_RELA, true, 32, true>;
1845 #endif
1846
1847 #ifdef HAVE_TARGET_64_LITTLE
1848 template
1849 class Output_data_reloc<elfcpp::SHT_RELA, true, 64, false>;
1850 #endif
1851
1852 #ifdef HAVE_TARGET_64_BIG
1853 template
1854 class Output_data_reloc<elfcpp::SHT_RELA, true, 64, true>;
1855 #endif
1856
1857 #ifdef HAVE_TARGET_32_LITTLE
1858 template
1859 class Output_data_got<32, false>;
1860 #endif
1861
1862 #ifdef HAVE_TARGET_32_BIG
1863 template
1864 class Output_data_got<32, true>;
1865 #endif
1866
1867 #ifdef HAVE_TARGET_64_LITTLE
1868 template
1869 class Output_data_got<64, false>;
1870 #endif
1871
1872 #ifdef HAVE_TARGET_64_BIG
1873 template
1874 class Output_data_got<64, true>;
1875 #endif
1876
1877 } // End namespace gold.