1 // output.cc -- manage the output file for gold
3 // Copyright 2006, 2007 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
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.
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.
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.
32 #include "libiberty.h" // for unlink_if_ordinary()
34 #include "parameters.h"
41 // Some BSD systems still use MAP_ANON instead of MAP_ANONYMOUS
43 # define MAP_ANONYMOUS MAP_ANON
49 // Output_data variables.
51 bool Output_data::allocated_sizes_are_fixed
;
53 // Output_data methods.
55 Output_data::~Output_data()
59 // Return the default alignment for the target size.
62 Output_data::default_alignment()
64 return Output_data::default_alignment_for_size(parameters
->get_size());
67 // Return the default alignment for a size--32 or 64.
70 Output_data::default_alignment_for_size(int size
)
80 // Output_section_header methods. This currently assumes that the
81 // segment and section lists are complete at construction time.
83 Output_section_headers::Output_section_headers(
85 const Layout::Segment_list
* segment_list
,
86 const Layout::Section_list
* unattached_section_list
,
87 const Stringpool
* secnamepool
)
89 segment_list_(segment_list
),
90 unattached_section_list_(unattached_section_list
),
91 secnamepool_(secnamepool
)
93 // Count all the sections. Start with 1 for the null section.
95 for (Layout::Segment_list::const_iterator p
= segment_list
->begin();
96 p
!= segment_list
->end();
98 if ((*p
)->type() == elfcpp::PT_LOAD
)
99 count
+= (*p
)->output_section_count();
100 count
+= unattached_section_list
->size();
102 const int size
= parameters
->get_size();
105 shdr_size
= elfcpp::Elf_sizes
<32>::shdr_size
;
107 shdr_size
= elfcpp::Elf_sizes
<64>::shdr_size
;
111 this->set_data_size(count
* shdr_size
);
114 // Write out the section headers.
117 Output_section_headers::do_write(Output_file
* of
)
119 if (parameters
->get_size() == 32)
121 if (parameters
->is_big_endian())
123 #ifdef HAVE_TARGET_32_BIG
124 this->do_sized_write
<32, true>(of
);
131 #ifdef HAVE_TARGET_32_LITTLE
132 this->do_sized_write
<32, false>(of
);
138 else if (parameters
->get_size() == 64)
140 if (parameters
->is_big_endian())
142 #ifdef HAVE_TARGET_64_BIG
143 this->do_sized_write
<64, true>(of
);
150 #ifdef HAVE_TARGET_64_LITTLE
151 this->do_sized_write
<64, false>(of
);
161 template<int size
, bool big_endian
>
163 Output_section_headers::do_sized_write(Output_file
* of
)
165 off_t all_shdrs_size
= this->data_size();
166 unsigned char* view
= of
->get_output_view(this->offset(), all_shdrs_size
);
168 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
169 unsigned char* v
= view
;
172 typename
elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
173 oshdr
.put_sh_name(0);
174 oshdr
.put_sh_type(elfcpp::SHT_NULL
);
175 oshdr
.put_sh_flags(0);
176 oshdr
.put_sh_addr(0);
177 oshdr
.put_sh_offset(0);
178 oshdr
.put_sh_size(0);
179 oshdr
.put_sh_link(0);
180 oshdr
.put_sh_info(0);
181 oshdr
.put_sh_addralign(0);
182 oshdr
.put_sh_entsize(0);
188 for (Layout::Segment_list::const_iterator p
= this->segment_list_
->begin();
189 p
!= this->segment_list_
->end();
191 v
= (*p
)->write_section_headers
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
192 this->layout_
, this->secnamepool_
, v
, &shndx
193 SELECT_SIZE_ENDIAN(size
, big_endian
));
194 for (Layout::Section_list::const_iterator p
=
195 this->unattached_section_list_
->begin();
196 p
!= this->unattached_section_list_
->end();
199 gold_assert(shndx
== (*p
)->out_shndx());
200 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
201 (*p
)->write_header(this->layout_
, this->secnamepool_
, &oshdr
);
206 of
->write_output_view(this->offset(), all_shdrs_size
, view
);
209 // Output_segment_header methods.
211 Output_segment_headers::Output_segment_headers(
212 const Layout::Segment_list
& segment_list
)
213 : segment_list_(segment_list
)
215 const int size
= parameters
->get_size();
218 phdr_size
= elfcpp::Elf_sizes
<32>::phdr_size
;
220 phdr_size
= elfcpp::Elf_sizes
<64>::phdr_size
;
224 this->set_data_size(segment_list
.size() * phdr_size
);
228 Output_segment_headers::do_write(Output_file
* of
)
230 if (parameters
->get_size() == 32)
232 if (parameters
->is_big_endian())
234 #ifdef HAVE_TARGET_32_BIG
235 this->do_sized_write
<32, true>(of
);
242 #ifdef HAVE_TARGET_32_LITTLE
243 this->do_sized_write
<32, false>(of
);
249 else if (parameters
->get_size() == 64)
251 if (parameters
->is_big_endian())
253 #ifdef HAVE_TARGET_64_BIG
254 this->do_sized_write
<64, true>(of
);
261 #ifdef HAVE_TARGET_64_LITTLE
262 this->do_sized_write
<64, false>(of
);
272 template<int size
, bool big_endian
>
274 Output_segment_headers::do_sized_write(Output_file
* of
)
276 const int phdr_size
= elfcpp::Elf_sizes
<size
>::phdr_size
;
277 off_t all_phdrs_size
= this->segment_list_
.size() * phdr_size
;
278 unsigned char* view
= of
->get_output_view(this->offset(),
280 unsigned char* v
= view
;
281 for (Layout::Segment_list::const_iterator p
= this->segment_list_
.begin();
282 p
!= this->segment_list_
.end();
285 elfcpp::Phdr_write
<size
, big_endian
> ophdr(v
);
286 (*p
)->write_header(&ophdr
);
290 of
->write_output_view(this->offset(), all_phdrs_size
, view
);
293 // Output_file_header methods.
295 Output_file_header::Output_file_header(const Target
* target
,
296 const Symbol_table
* symtab
,
297 const Output_segment_headers
* osh
)
300 segment_header_(osh
),
301 section_header_(NULL
),
304 const int size
= parameters
->get_size();
307 ehdr_size
= elfcpp::Elf_sizes
<32>::ehdr_size
;
309 ehdr_size
= elfcpp::Elf_sizes
<64>::ehdr_size
;
313 this->set_data_size(ehdr_size
);
316 // Set the section table information for a file header.
319 Output_file_header::set_section_info(const Output_section_headers
* shdrs
,
320 const Output_section
* shstrtab
)
322 this->section_header_
= shdrs
;
323 this->shstrtab_
= shstrtab
;
326 // Write out the file header.
329 Output_file_header::do_write(Output_file
* of
)
331 gold_assert(this->offset() == 0);
333 if (parameters
->get_size() == 32)
335 if (parameters
->is_big_endian())
337 #ifdef HAVE_TARGET_32_BIG
338 this->do_sized_write
<32, true>(of
);
345 #ifdef HAVE_TARGET_32_LITTLE
346 this->do_sized_write
<32, false>(of
);
352 else if (parameters
->get_size() == 64)
354 if (parameters
->is_big_endian())
356 #ifdef HAVE_TARGET_64_BIG
357 this->do_sized_write
<64, true>(of
);
364 #ifdef HAVE_TARGET_64_LITTLE
365 this->do_sized_write
<64, false>(of
);
375 // Write out the file header with appropriate size and endianess.
377 template<int size
, bool big_endian
>
379 Output_file_header::do_sized_write(Output_file
* of
)
381 gold_assert(this->offset() == 0);
383 int ehdr_size
= elfcpp::Elf_sizes
<size
>::ehdr_size
;
384 unsigned char* view
= of
->get_output_view(0, ehdr_size
);
385 elfcpp::Ehdr_write
<size
, big_endian
> oehdr(view
);
387 unsigned char e_ident
[elfcpp::EI_NIDENT
];
388 memset(e_ident
, 0, elfcpp::EI_NIDENT
);
389 e_ident
[elfcpp::EI_MAG0
] = elfcpp::ELFMAG0
;
390 e_ident
[elfcpp::EI_MAG1
] = elfcpp::ELFMAG1
;
391 e_ident
[elfcpp::EI_MAG2
] = elfcpp::ELFMAG2
;
392 e_ident
[elfcpp::EI_MAG3
] = elfcpp::ELFMAG3
;
394 e_ident
[elfcpp::EI_CLASS
] = elfcpp::ELFCLASS32
;
396 e_ident
[elfcpp::EI_CLASS
] = elfcpp::ELFCLASS64
;
399 e_ident
[elfcpp::EI_DATA
] = (big_endian
400 ? elfcpp::ELFDATA2MSB
401 : elfcpp::ELFDATA2LSB
);
402 e_ident
[elfcpp::EI_VERSION
] = elfcpp::EV_CURRENT
;
403 // FIXME: Some targets may need to set EI_OSABI and EI_ABIVERSION.
404 oehdr
.put_e_ident(e_ident
);
407 if (parameters
->output_is_object())
408 e_type
= elfcpp::ET_REL
;
409 else if (parameters
->output_is_shared())
410 e_type
= elfcpp::ET_DYN
;
412 e_type
= elfcpp::ET_EXEC
;
413 oehdr
.put_e_type(e_type
);
415 oehdr
.put_e_machine(this->target_
->machine_code());
416 oehdr
.put_e_version(elfcpp::EV_CURRENT
);
418 // FIXME: Need to support -e, and target specific entry symbol.
419 Symbol
* sym
= this->symtab_
->lookup("_start");
420 typename Sized_symbol
<size
>::Value_type v
;
425 Sized_symbol
<size
>* ssym
;
426 ssym
= this->symtab_
->get_sized_symbol
SELECT_SIZE_NAME(size
) (
427 sym
SELECT_SIZE(size
));
430 oehdr
.put_e_entry(v
);
432 oehdr
.put_e_phoff(this->segment_header_
->offset());
433 oehdr
.put_e_shoff(this->section_header_
->offset());
435 // FIXME: The target needs to set the flags.
436 oehdr
.put_e_flags(0);
438 oehdr
.put_e_ehsize(elfcpp::Elf_sizes
<size
>::ehdr_size
);
439 oehdr
.put_e_phentsize(elfcpp::Elf_sizes
<size
>::phdr_size
);
440 oehdr
.put_e_phnum(this->segment_header_
->data_size()
441 / elfcpp::Elf_sizes
<size
>::phdr_size
);
442 oehdr
.put_e_shentsize(elfcpp::Elf_sizes
<size
>::shdr_size
);
443 oehdr
.put_e_shnum(this->section_header_
->data_size()
444 / elfcpp::Elf_sizes
<size
>::shdr_size
);
445 oehdr
.put_e_shstrndx(this->shstrtab_
->out_shndx());
447 of
->write_output_view(0, ehdr_size
, view
);
450 // Output_data_const methods.
453 Output_data_const::do_write(Output_file
* of
)
455 of
->write(this->offset(), this->data_
.data(), this->data_
.size());
458 // Output_data_const_buffer methods.
461 Output_data_const_buffer::do_write(Output_file
* of
)
463 of
->write(this->offset(), this->p_
, this->data_size());
466 // Output_section_data methods.
468 // Record the output section, and set the entry size and such.
471 Output_section_data::set_output_section(Output_section
* os
)
473 gold_assert(this->output_section_
== NULL
);
474 this->output_section_
= os
;
475 this->do_adjust_output_section(os
);
478 // Return the section index of the output section.
481 Output_section_data::do_out_shndx() const
483 gold_assert(this->output_section_
!= NULL
);
484 return this->output_section_
->out_shndx();
487 // Output_data_strtab methods.
489 // Set the final data size.
492 Output_data_strtab::set_final_data_size()
494 this->strtab_
->set_string_offsets();
495 this->set_data_size(this->strtab_
->get_strtab_size());
498 // Write out a string table.
501 Output_data_strtab::do_write(Output_file
* of
)
503 this->strtab_
->write(of
, this->offset());
506 // Output_reloc methods.
508 // Get the symbol index of a relocation.
510 template<bool dynamic
, int size
, bool big_endian
>
512 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::get_symbol_index()
516 switch (this->local_sym_index_
)
522 if (this->u1_
.gsym
== NULL
)
525 index
= this->u1_
.gsym
->dynsym_index();
527 index
= this->u1_
.gsym
->symtab_index();
532 index
= this->u1_
.os
->dynsym_index();
534 index
= this->u1_
.os
->symtab_index();
538 // Relocations without symbols use a symbol index of 0.
545 // FIXME: It seems that some targets may need to generate
546 // dynamic relocations against local symbols for some
547 // reasons. This will have to be addressed at some point.
551 index
= this->u1_
.relobj
->symtab_index(this->local_sym_index_
);
554 gold_assert(index
!= -1U);
558 // Write out the offset and info fields of a Rel or Rela relocation
561 template<bool dynamic
, int size
, bool big_endian
>
562 template<typename Write_rel
>
564 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write_rel(
567 Address address
= this->address_
;
568 if (this->shndx_
!= INVALID_CODE
)
571 Output_section
* os
= this->u2_
.relobj
->output_section(this->shndx_
,
573 gold_assert(os
!= NULL
);
575 address
+= os
->address() + off
;
578 address
= os
->output_address(this->u2_
.relobj
, this->shndx_
,
580 gold_assert(address
!= -1U);
583 else if (this->u2_
.od
!= NULL
)
584 address
+= this->u2_
.od
->address();
585 wr
->put_r_offset(address
);
586 wr
->put_r_info(elfcpp::elf_r_info
<size
>(this->get_symbol_index(),
590 // Write out a Rel relocation.
592 template<bool dynamic
, int size
, bool big_endian
>
594 Output_reloc
<elfcpp::SHT_REL
, dynamic
, size
, big_endian
>::write(
595 unsigned char* pov
) const
597 elfcpp::Rel_write
<size
, big_endian
> orel(pov
);
598 this->write_rel(&orel
);
601 // Write out a Rela relocation.
603 template<bool dynamic
, int size
, bool big_endian
>
605 Output_reloc
<elfcpp::SHT_RELA
, dynamic
, size
, big_endian
>::write(
606 unsigned char* pov
) const
608 elfcpp::Rela_write
<size
, big_endian
> orel(pov
);
609 this->rel_
.write_rel(&orel
);
610 orel
.put_r_addend(this->addend_
);
613 // Output_data_reloc_base methods.
615 // Adjust the output section.
617 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
619 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>
620 ::do_adjust_output_section(Output_section
* os
)
622 if (sh_type
== elfcpp::SHT_REL
)
623 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rel_size
);
624 else if (sh_type
== elfcpp::SHT_RELA
)
625 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rela_size
);
629 os
->set_should_link_to_dynsym();
631 os
->set_should_link_to_symtab();
634 // Write out relocation data.
636 template<int sh_type
, bool dynamic
, int size
, bool big_endian
>
638 Output_data_reloc_base
<sh_type
, dynamic
, size
, big_endian
>::do_write(
641 const off_t off
= this->offset();
642 const off_t oview_size
= this->data_size();
643 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
645 unsigned char* pov
= oview
;
646 for (typename
Relocs::const_iterator p
= this->relocs_
.begin();
647 p
!= this->relocs_
.end();
654 gold_assert(pov
- oview
== oview_size
);
656 of
->write_output_view(off
, oview_size
, oview
);
658 // We no longer need the relocation entries.
659 this->relocs_
.clear();
662 // Output_data_got::Got_entry methods.
664 // Write out the entry.
666 template<int size
, bool big_endian
>
668 Output_data_got
<size
, big_endian
>::Got_entry::write(unsigned char* pov
) const
672 switch (this->local_sym_index_
)
676 Symbol
* gsym
= this->u_
.gsym
;
678 // If the symbol is resolved locally, we need to write out its
679 // value. Otherwise we just write zero. The target code is
680 // responsible for creating a relocation entry to fill in the
681 // value at runtime. For non-preemptible symbols in a shared
682 // library, the target will need to record whether or not the
683 // value should be written (e.g., it may use a RELATIVE
685 if (gsym
->final_value_is_known() || gsym
->needs_value_in_got())
687 Sized_symbol
<size
>* sgsym
;
688 // This cast is a bit ugly. We don't want to put a
689 // virtual method in Symbol, because we want Symbol to be
690 // as small as possible.
691 sgsym
= static_cast<Sized_symbol
<size
>*>(gsym
);
692 val
= sgsym
->value();
698 val
= this->u_
.constant
;
702 val
= this->u_
.object
->local_symbol_value(this->local_sym_index_
);
706 elfcpp::Swap
<size
, big_endian
>::writeval(pov
, val
);
709 // Output_data_got methods.
711 // Add an entry for a global symbol to the GOT. This returns true if
712 // this is a new GOT entry, false if the symbol already had a GOT
715 template<int size
, bool big_endian
>
717 Output_data_got
<size
, big_endian
>::add_global(Symbol
* gsym
)
719 if (gsym
->has_got_offset())
722 this->entries_
.push_back(Got_entry(gsym
));
723 this->set_got_size();
724 gsym
->set_got_offset(this->last_got_offset());
728 // Add an entry for a local symbol to the GOT. This returns true if
729 // this is a new GOT entry, false if the symbol already has a GOT
732 template<int size
, bool big_endian
>
734 Output_data_got
<size
, big_endian
>::add_local(
735 Sized_relobj
<size
, big_endian
>* object
,
738 if (object
->local_has_got_offset(symndx
))
741 this->entries_
.push_back(Got_entry(object
, symndx
));
742 this->set_got_size();
743 object
->set_local_got_offset(symndx
, this->last_got_offset());
747 // Add an entry (or a pair of entries) for a global TLS symbol to the GOT.
748 // In a pair of entries, the first value in the pair will be used for the
749 // module index, and the second value will be used for the dtv-relative
750 // offset. This returns true if this is a new GOT entry, false if the symbol
751 // already has a GOT entry.
753 template<int size
, bool big_endian
>
755 Output_data_got
<size
, big_endian
>::add_global_tls(Symbol
* gsym
,
758 if (gsym
->has_tls_got_offset(need_pair
))
761 this->entries_
.push_back(Got_entry(gsym
));
762 gsym
->set_tls_got_offset(this->last_got_offset(), need_pair
);
764 this->entries_
.push_back(Got_entry(gsym
));
765 this->set_got_size();
769 // Add an entry (or a pair of entries) for a local TLS symbol to the GOT.
770 // In a pair of entries, the first value in the pair will be used for the
771 // module index, and the second value will be used for the dtv-relative
772 // offset. This returns true if this is a new GOT entry, false if the symbol
773 // already has a GOT entry.
775 template<int size
, bool big_endian
>
777 Output_data_got
<size
, big_endian
>::add_local_tls(
778 Sized_relobj
<size
, big_endian
>* object
,
782 if (object
->local_has_tls_got_offset(symndx
, need_pair
))
785 this->entries_
.push_back(Got_entry(object
, symndx
));
786 object
->set_local_tls_got_offset(symndx
, this->last_got_offset(), need_pair
);
788 this->entries_
.push_back(Got_entry(object
, symndx
));
789 this->set_got_size();
793 // Write out the GOT.
795 template<int size
, bool big_endian
>
797 Output_data_got
<size
, big_endian
>::do_write(Output_file
* of
)
799 const int add
= size
/ 8;
801 const off_t off
= this->offset();
802 const off_t oview_size
= this->data_size();
803 unsigned char* const oview
= of
->get_output_view(off
, oview_size
);
805 unsigned char* pov
= oview
;
806 for (typename
Got_entries::const_iterator p
= this->entries_
.begin();
807 p
!= this->entries_
.end();
814 gold_assert(pov
- oview
== oview_size
);
816 of
->write_output_view(off
, oview_size
, oview
);
818 // We no longer need the GOT entries.
819 this->entries_
.clear();
822 // Output_data_dynamic::Dynamic_entry methods.
824 // Write out the entry.
826 template<int size
, bool big_endian
>
828 Output_data_dynamic::Dynamic_entry::write(
830 const Stringpool
* pool
831 ACCEPT_SIZE_ENDIAN
) const
833 typename
elfcpp::Elf_types
<size
>::Elf_WXword val
;
834 switch (this->classification_
)
840 case DYNAMIC_SECTION_ADDRESS
:
841 val
= this->u_
.od
->address();
844 case DYNAMIC_SECTION_SIZE
:
845 val
= this->u_
.od
->data_size();
850 const Sized_symbol
<size
>* s
=
851 static_cast<const Sized_symbol
<size
>*>(this->u_
.sym
);
857 val
= pool
->get_offset(this->u_
.str
);
864 elfcpp::Dyn_write
<size
, big_endian
> dw(pov
);
865 dw
.put_d_tag(this->tag_
);
869 // Output_data_dynamic methods.
871 // Adjust the output section to set the entry size.
874 Output_data_dynamic::do_adjust_output_section(Output_section
* os
)
876 if (parameters
->get_size() == 32)
877 os
->set_entsize(elfcpp::Elf_sizes
<32>::dyn_size
);
878 else if (parameters
->get_size() == 64)
879 os
->set_entsize(elfcpp::Elf_sizes
<64>::dyn_size
);
884 // Set the final data size.
887 Output_data_dynamic::set_final_data_size()
889 // Add the terminating entry.
890 this->add_constant(elfcpp::DT_NULL
, 0);
893 if (parameters
->get_size() == 32)
894 dyn_size
= elfcpp::Elf_sizes
<32>::dyn_size
;
895 else if (parameters
->get_size() == 64)
896 dyn_size
= elfcpp::Elf_sizes
<64>::dyn_size
;
899 this->set_data_size(this->entries_
.size() * dyn_size
);
902 // Write out the dynamic entries.
905 Output_data_dynamic::do_write(Output_file
* of
)
907 if (parameters
->get_size() == 32)
909 if (parameters
->is_big_endian())
911 #ifdef HAVE_TARGET_32_BIG
912 this->sized_write
<32, true>(of
);
919 #ifdef HAVE_TARGET_32_LITTLE
920 this->sized_write
<32, false>(of
);
926 else if (parameters
->get_size() == 64)
928 if (parameters
->is_big_endian())
930 #ifdef HAVE_TARGET_64_BIG
931 this->sized_write
<64, true>(of
);
938 #ifdef HAVE_TARGET_64_LITTLE
939 this->sized_write
<64, false>(of
);
949 template<int size
, bool big_endian
>
951 Output_data_dynamic::sized_write(Output_file
* of
)
953 const int dyn_size
= elfcpp::Elf_sizes
<size
>::dyn_size
;
955 const off_t offset
= this->offset();
956 const off_t oview_size
= this->data_size();
957 unsigned char* const oview
= of
->get_output_view(offset
, oview_size
);
959 unsigned char* pov
= oview
;
960 for (typename
Dynamic_entries::const_iterator p
= this->entries_
.begin();
961 p
!= this->entries_
.end();
964 p
->write
SELECT_SIZE_ENDIAN_NAME(size
, big_endian
)(
965 pov
, this->pool_
SELECT_SIZE_ENDIAN(size
, big_endian
));
969 gold_assert(pov
- oview
== oview_size
);
971 of
->write_output_view(offset
, oview_size
, oview
);
973 // We no longer need the dynamic entries.
974 this->entries_
.clear();
977 // Output_section::Input_section methods.
979 // Return the data size. For an input section we store the size here.
980 // For an Output_section_data, we have to ask it for the size.
983 Output_section::Input_section::data_size() const
985 if (this->is_input_section())
986 return this->u1_
.data_size
;
988 return this->u2_
.posd
->data_size();
991 // Set the address and file offset.
994 Output_section::Input_section::set_address_and_file_offset(
997 off_t section_file_offset
)
999 if (this->is_input_section())
1000 this->u2_
.object
->set_section_offset(this->shndx_
,
1001 file_offset
- section_file_offset
);
1003 this->u2_
.posd
->set_address_and_file_offset(address
, file_offset
);
1006 // Finalize the data size.
1009 Output_section::Input_section::finalize_data_size()
1011 if (!this->is_input_section())
1012 this->u2_
.posd
->finalize_data_size();
1015 // Try to turn an input offset into an output offset.
1018 Output_section::Input_section::output_offset(const Relobj
* object
,
1021 off_t
*poutput
) const
1023 if (!this->is_input_section())
1024 return this->u2_
.posd
->output_offset(object
, shndx
, offset
, poutput
);
1027 if (this->shndx_
!= shndx
|| this->u2_
.object
!= object
)
1029 off_t output_offset
;
1030 Output_section
* os
= object
->output_section(shndx
, &output_offset
);
1031 gold_assert(os
!= NULL
);
1032 gold_assert(output_offset
!= -1);
1033 *poutput
= output_offset
+ offset
;
1038 // Write out the data. We don't have to do anything for an input
1039 // section--they are handled via Object::relocate--but this is where
1040 // we write out the data for an Output_section_data.
1043 Output_section::Input_section::write(Output_file
* of
)
1045 if (!this->is_input_section())
1046 this->u2_
.posd
->write(of
);
1049 // Write the data to a buffer. As for write(), we don't have to do
1050 // anything for an input section.
1053 Output_section::Input_section::write_to_buffer(unsigned char* buffer
)
1055 if (!this->is_input_section())
1056 this->u2_
.posd
->write_to_buffer(buffer
);
1059 // Output_section methods.
1061 // Construct an Output_section. NAME will point into a Stringpool.
1063 Output_section::Output_section(const char* name
, elfcpp::Elf_Word type
,
1064 elfcpp::Elf_Xword flags
)
1068 link_section_(NULL
),
1070 info_section_(NULL
),
1078 first_input_offset_(0),
1080 postprocessing_buffer_(NULL
),
1081 needs_symtab_index_(false),
1082 needs_dynsym_index_(false),
1083 should_link_to_symtab_(false),
1084 should_link_to_dynsym_(false),
1085 after_input_sections_(false),
1086 requires_postprocessing_(false)
1088 // An unallocated section has no address. Forcing this means that
1089 // we don't need special treatment for symbols defined in debug
1091 if ((flags
& elfcpp::SHF_ALLOC
) == 0)
1092 this->set_address(0);
1095 Output_section::~Output_section()
1099 // Set the entry size.
1102 Output_section::set_entsize(uint64_t v
)
1104 if (this->entsize_
== 0)
1107 gold_assert(this->entsize_
== v
);
1110 // Add the input section SHNDX, with header SHDR, named SECNAME, in
1111 // OBJECT, to the Output_section. RELOC_SHNDX is the index of a
1112 // relocation section which applies to this section, or 0 if none, or
1113 // -1U if more than one. Return the offset of the input section
1114 // within the output section. Return -1 if the input section will
1115 // receive special handling. In the normal case we don't always keep
1116 // track of input sections for an Output_section. Instead, each
1117 // Object keeps track of the Output_section for each of its input
1120 template<int size
, bool big_endian
>
1122 Output_section::add_input_section(Sized_relobj
<size
, big_endian
>* object
,
1124 const char* secname
,
1125 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
1126 unsigned int reloc_shndx
)
1128 elfcpp::Elf_Xword addralign
= shdr
.get_sh_addralign();
1129 if ((addralign
& (addralign
- 1)) != 0)
1131 object
->error(_("invalid alignment %lu for section \"%s\""),
1132 static_cast<unsigned long>(addralign
), secname
);
1136 if (addralign
> this->addralign_
)
1137 this->addralign_
= addralign
;
1139 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_flags
= shdr
.get_sh_flags();
1140 uint64_t entsize
= shdr
.get_sh_entsize();
1142 // .debug_str is a mergeable string section, but is not always so
1143 // marked by compilers. Mark manually here so we can optimize.
1144 if (strcmp(secname
, ".debug_str") == 0)
1146 sh_flags
|= (elfcpp::SHF_MERGE
| elfcpp::SHF_STRINGS
);
1150 // If this is a SHF_MERGE section, we pass all the input sections to
1151 // a Output_data_merge. We don't try to handle relocations for such
1153 if ((sh_flags
& elfcpp::SHF_MERGE
) != 0
1154 && reloc_shndx
== 0)
1156 if (this->add_merge_input_section(object
, shndx
, sh_flags
,
1157 entsize
, addralign
))
1159 // Tell the relocation routines that they need to call the
1160 // output_offset method to determine the final address.
1165 off_t offset_in_section
= this->current_data_size_for_child();
1166 off_t aligned_offset_in_section
= align_address(offset_in_section
,
1169 if (aligned_offset_in_section
> offset_in_section
1170 && (sh_flags
& elfcpp::SHF_EXECINSTR
) != 0
1171 && object
->target()->has_code_fill())
1173 // We need to add some fill data. Using fill_list_ when
1174 // possible is an optimization, since we will often have fill
1175 // sections without input sections.
1176 off_t fill_len
= aligned_offset_in_section
- offset_in_section
;
1177 if (this->input_sections_
.empty())
1178 this->fills_
.push_back(Fill(offset_in_section
, fill_len
));
1181 // FIXME: When relaxing, the size needs to adjust to
1182 // maintain a constant alignment.
1183 std::string
fill_data(object
->target()->code_fill(fill_len
));
1184 Output_data_const
* odc
= new Output_data_const(fill_data
, 1);
1185 this->input_sections_
.push_back(Input_section(odc
));
1189 this->set_current_data_size_for_child(aligned_offset_in_section
1190 + shdr
.get_sh_size());
1192 // We need to keep track of this section if we are already keeping
1193 // track of sections, or if we are relaxing. FIXME: Add test for
1195 if (!this->input_sections_
.empty())
1196 this->input_sections_
.push_back(Input_section(object
, shndx
,
1200 return aligned_offset_in_section
;
1203 // Add arbitrary data to an output section.
1206 Output_section::add_output_section_data(Output_section_data
* posd
)
1208 Input_section
inp(posd
);
1209 this->add_output_section_data(&inp
);
1212 // Add arbitrary data to an output section by Input_section.
1215 Output_section::add_output_section_data(Input_section
* inp
)
1217 if (this->input_sections_
.empty())
1218 this->first_input_offset_
= this->current_data_size_for_child();
1220 this->input_sections_
.push_back(*inp
);
1222 uint64_t addralign
= inp
->addralign();
1223 if (addralign
> this->addralign_
)
1224 this->addralign_
= addralign
;
1226 inp
->set_output_section(this);
1229 // Add a merge section to an output section.
1232 Output_section::add_output_merge_section(Output_section_data
* posd
,
1233 bool is_string
, uint64_t entsize
)
1235 Input_section
inp(posd
, is_string
, entsize
);
1236 this->add_output_section_data(&inp
);
1239 // Add an input section to a SHF_MERGE section.
1242 Output_section::add_merge_input_section(Relobj
* object
, unsigned int shndx
,
1243 uint64_t flags
, uint64_t entsize
,
1246 bool is_string
= (flags
& elfcpp::SHF_STRINGS
) != 0;
1248 // We only merge strings if the alignment is not more than the
1249 // character size. This could be handled, but it's unusual.
1250 if (is_string
&& addralign
> entsize
)
1253 Input_section_list::iterator p
;
1254 for (p
= this->input_sections_
.begin();
1255 p
!= this->input_sections_
.end();
1257 if (p
->is_merge_section(is_string
, entsize
, addralign
))
1259 p
->add_input_section(object
, shndx
);
1263 // We handle the actual constant merging in Output_merge_data or
1264 // Output_merge_string_data.
1265 Output_section_data
* posd
;
1267 posd
= new Output_merge_data(entsize
, addralign
);
1273 posd
= new Output_merge_string
<char>(addralign
);
1276 posd
= new Output_merge_string
<uint16_t>(addralign
);
1279 posd
= new Output_merge_string
<uint32_t>(addralign
);
1286 this->add_output_merge_section(posd
, is_string
, entsize
);
1287 posd
->add_input_section(object
, shndx
);
1292 // Given an address OFFSET relative to the start of input section
1293 // SHNDX in OBJECT, return whether this address is being included in
1294 // the final link. This should only be called if SHNDX in OBJECT has
1295 // a special mapping.
1298 Output_section::is_input_address_mapped(const Relobj
* object
,
1302 gold_assert(object
->is_section_specially_mapped(shndx
));
1304 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
1305 p
!= this->input_sections_
.end();
1308 off_t output_offset
;
1309 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
1310 return output_offset
!= -1;
1313 // By default we assume that the address is mapped. This should
1314 // only be called after we have passed all sections to Layout. At
1315 // that point we should know what we are discarding.
1319 // Given an address OFFSET relative to the start of input section
1320 // SHNDX in object OBJECT, return the output offset relative to the
1321 // start of the section. This should only be called if SHNDX in
1322 // OBJECT has a special mapping.
1325 Output_section::output_offset(const Relobj
* object
, unsigned int shndx
,
1328 gold_assert(object
->is_section_specially_mapped(shndx
));
1329 // This can only be called meaningfully when layout is complete.
1330 gold_assert(Output_data::is_layout_complete());
1332 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
1333 p
!= this->input_sections_
.end();
1336 off_t output_offset
;
1337 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
1338 return output_offset
;
1343 // Return the output virtual address of OFFSET relative to the start
1344 // of input section SHNDX in object OBJECT.
1347 Output_section::output_address(const Relobj
* object
, unsigned int shndx
,
1350 gold_assert(object
->is_section_specially_mapped(shndx
));
1351 // This can only be called meaningfully when layout is complete.
1352 gold_assert(Output_data::is_layout_complete());
1354 uint64_t addr
= this->address() + this->first_input_offset_
;
1355 for (Input_section_list::const_iterator p
= this->input_sections_
.begin();
1356 p
!= this->input_sections_
.end();
1359 addr
= align_address(addr
, p
->addralign());
1360 off_t output_offset
;
1361 if (p
->output_offset(object
, shndx
, offset
, &output_offset
))
1363 if (output_offset
== -1)
1365 return addr
+ output_offset
;
1367 addr
+= p
->data_size();
1370 // If we get here, it means that we don't know the mapping for this
1371 // input section. This might happen in principle if
1372 // add_input_section were called before add_output_section_data.
1373 // But it should never actually happen.
1378 // Set the data size of an Output_section. This is where we handle
1379 // setting the addresses of any Output_section_data objects.
1382 Output_section::set_final_data_size()
1384 if (this->input_sections_
.empty())
1386 this->set_data_size(this->current_data_size_for_child());
1390 uint64_t address
= this->address();
1391 off_t startoff
= this->offset();
1392 off_t off
= startoff
+ this->first_input_offset_
;
1393 for (Input_section_list::iterator p
= this->input_sections_
.begin();
1394 p
!= this->input_sections_
.end();
1397 off
= align_address(off
, p
->addralign());
1398 p
->set_address_and_file_offset(address
+ (off
- startoff
), off
,
1400 off
+= p
->data_size();
1403 this->set_data_size(off
- startoff
);
1406 // Write the section header to *OSHDR.
1408 template<int size
, bool big_endian
>
1410 Output_section::write_header(const Layout
* layout
,
1411 const Stringpool
* secnamepool
,
1412 elfcpp::Shdr_write
<size
, big_endian
>* oshdr
) const
1414 oshdr
->put_sh_name(secnamepool
->get_offset(this->name_
));
1415 oshdr
->put_sh_type(this->type_
);
1416 oshdr
->put_sh_flags(this->flags_
);
1417 oshdr
->put_sh_addr(this->address());
1418 oshdr
->put_sh_offset(this->offset());
1419 oshdr
->put_sh_size(this->data_size());
1420 if (this->link_section_
!= NULL
)
1421 oshdr
->put_sh_link(this->link_section_
->out_shndx());
1422 else if (this->should_link_to_symtab_
)
1423 oshdr
->put_sh_link(layout
->symtab_section()->out_shndx());
1424 else if (this->should_link_to_dynsym_
)
1425 oshdr
->put_sh_link(layout
->dynsym_section()->out_shndx());
1427 oshdr
->put_sh_link(this->link_
);
1428 if (this->info_section_
!= NULL
)
1429 oshdr
->put_sh_info(this->info_section_
->out_shndx());
1431 oshdr
->put_sh_info(this->info_
);
1432 oshdr
->put_sh_addralign(this->addralign_
);
1433 oshdr
->put_sh_entsize(this->entsize_
);
1436 // Write out the data. For input sections the data is written out by
1437 // Object::relocate, but we have to handle Output_section_data objects
1441 Output_section::do_write(Output_file
* of
)
1443 gold_assert(!this->requires_postprocessing());
1445 off_t output_section_file_offset
= this->offset();
1446 for (Fill_list::iterator p
= this->fills_
.begin();
1447 p
!= this->fills_
.end();
1450 std::string
fill_data(of
->target()->code_fill(p
->length()));
1451 of
->write(output_section_file_offset
+ p
->section_offset(),
1452 fill_data
.data(), fill_data
.size());
1455 for (Input_section_list::iterator p
= this->input_sections_
.begin();
1456 p
!= this->input_sections_
.end();
1461 // If a section requires postprocessing, create the buffer to use.
1464 Output_section::create_postprocessing_buffer()
1466 gold_assert(this->requires_postprocessing());
1467 gold_assert(this->postprocessing_buffer_
== NULL
);
1469 if (!this->input_sections_
.empty())
1471 off_t off
= this->first_input_offset_
;
1472 for (Input_section_list::iterator p
= this->input_sections_
.begin();
1473 p
!= this->input_sections_
.end();
1476 off
= align_address(off
, p
->addralign());
1477 p
->finalize_data_size();
1478 off
+= p
->data_size();
1480 this->set_current_data_size_for_child(off
);
1483 off_t buffer_size
= this->current_data_size_for_child();
1484 this->postprocessing_buffer_
= new unsigned char[buffer_size
];
1487 // Write all the data of an Output_section into the postprocessing
1488 // buffer. This is used for sections which require postprocessing,
1489 // such as compression. Input sections are handled by
1490 // Object::Relocate.
1493 Output_section::write_to_postprocessing_buffer()
1495 gold_assert(this->requires_postprocessing());
1497 Target
* target
= parameters
->target();
1498 unsigned char* buffer
= this->postprocessing_buffer();
1499 for (Fill_list::iterator p
= this->fills_
.begin();
1500 p
!= this->fills_
.end();
1503 std::string
fill_data(target
->code_fill(p
->length()));
1504 memcpy(buffer
+ p
->section_offset(), fill_data
.data(), fill_data
.size());
1507 off_t off
= this->first_input_offset_
;
1508 for (Input_section_list::iterator p
= this->input_sections_
.begin();
1509 p
!= this->input_sections_
.end();
1512 off
= align_address(off
, p
->addralign());
1513 p
->write_to_buffer(buffer
+ off
);
1514 off
+= p
->data_size();
1518 // Output segment methods.
1520 Output_segment::Output_segment(elfcpp::Elf_Word type
, elfcpp::Elf_Word flags
)
1531 is_align_known_(false)
1535 // Add an Output_section to an Output_segment.
1538 Output_segment::add_output_section(Output_section
* os
,
1539 elfcpp::Elf_Word seg_flags
,
1542 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
1543 gold_assert(!this->is_align_known_
);
1545 // Update the segment flags.
1546 this->flags_
|= seg_flags
;
1548 Output_segment::Output_data_list
* pdl
;
1549 if (os
->type() == elfcpp::SHT_NOBITS
)
1550 pdl
= &this->output_bss_
;
1552 pdl
= &this->output_data_
;
1554 // So that PT_NOTE segments will work correctly, we need to ensure
1555 // that all SHT_NOTE sections are adjacent. This will normally
1556 // happen automatically, because all the SHT_NOTE input sections
1557 // will wind up in the same output section. However, it is possible
1558 // for multiple SHT_NOTE input sections to have different section
1559 // flags, and thus be in different output sections, but for the
1560 // different section flags to map into the same segment flags and
1561 // thus the same output segment.
1563 // Note that while there may be many input sections in an output
1564 // section, there are normally only a few output sections in an
1565 // output segment. This loop is expected to be fast.
1567 if (os
->type() == elfcpp::SHT_NOTE
&& !pdl
->empty())
1569 Output_segment::Output_data_list::iterator p
= pdl
->end();
1573 if ((*p
)->is_section_type(elfcpp::SHT_NOTE
))
1575 // We don't worry about the FRONT parameter.
1581 while (p
!= pdl
->begin());
1584 // Similarly, so that PT_TLS segments will work, we need to group
1585 // SHF_TLS sections. An SHF_TLS/SHT_NOBITS section is a special
1586 // case: we group the SHF_TLS/SHT_NOBITS sections right after the
1587 // SHF_TLS/SHT_PROGBITS sections. This lets us set up PT_TLS
1588 // correctly. SHF_TLS sections get added to both a PT_LOAD segment
1589 // and the PT_TLS segment -- we do this grouping only for the
1591 if (this->type_
!= elfcpp::PT_TLS
1592 && (os
->flags() & elfcpp::SHF_TLS
) != 0
1593 && !this->output_data_
.empty())
1595 pdl
= &this->output_data_
;
1596 bool nobits
= os
->type() == elfcpp::SHT_NOBITS
;
1597 bool sawtls
= false;
1598 Output_segment::Output_data_list::iterator p
= pdl
->end();
1603 if ((*p
)->is_section_flag_set(elfcpp::SHF_TLS
))
1606 // Put a NOBITS section after the first TLS section.
1607 // But a PROGBITS section after the first TLS/PROGBITS
1609 insert
= nobits
|| !(*p
)->is_section_type(elfcpp::SHT_NOBITS
);
1613 // If we've gone past the TLS sections, but we've seen a
1614 // TLS section, then we need to insert this section now.
1620 // We don't worry about the FRONT parameter.
1626 while (p
!= pdl
->begin());
1628 // There are no TLS sections yet; put this one at the requested
1629 // location in the section list.
1633 pdl
->push_front(os
);
1638 // Add an Output_data (which is not an Output_section) to the start of
1642 Output_segment::add_initial_output_data(Output_data
* od
)
1644 gold_assert(!this->is_align_known_
);
1645 this->output_data_
.push_front(od
);
1648 // Return the maximum alignment of the Output_data in Output_segment.
1649 // Once we compute this, we prohibit new sections from being added.
1652 Output_segment::addralign()
1654 if (!this->is_align_known_
)
1658 addralign
= Output_segment::maximum_alignment(&this->output_data_
);
1659 if (addralign
> this->align_
)
1660 this->align_
= addralign
;
1662 addralign
= Output_segment::maximum_alignment(&this->output_bss_
);
1663 if (addralign
> this->align_
)
1664 this->align_
= addralign
;
1666 this->is_align_known_
= true;
1669 return this->align_
;
1672 // Return the maximum alignment of a list of Output_data.
1675 Output_segment::maximum_alignment(const Output_data_list
* pdl
)
1678 for (Output_data_list::const_iterator p
= pdl
->begin();
1682 uint64_t addralign
= (*p
)->addralign();
1683 if (addralign
> ret
)
1689 // Return the number of dynamic relocs applied to this segment.
1692 Output_segment::dynamic_reloc_count() const
1694 return (this->dynamic_reloc_count_list(&this->output_data_
)
1695 + this->dynamic_reloc_count_list(&this->output_bss_
));
1698 // Return the number of dynamic relocs applied to an Output_data_list.
1701 Output_segment::dynamic_reloc_count_list(const Output_data_list
* pdl
) const
1703 unsigned int count
= 0;
1704 for (Output_data_list::const_iterator p
= pdl
->begin();
1707 count
+= (*p
)->dynamic_reloc_count();
1711 // Set the section addresses for an Output_segment. ADDR is the
1712 // address and *POFF is the file offset. Set the section indexes
1713 // starting with *PSHNDX. Return the address of the immediately
1714 // following segment. Update *POFF and *PSHNDX.
1717 Output_segment::set_section_addresses(uint64_t addr
, off_t
* poff
,
1718 unsigned int* pshndx
)
1720 gold_assert(this->type_
== elfcpp::PT_LOAD
);
1722 this->vaddr_
= addr
;
1723 this->paddr_
= addr
;
1725 off_t orig_off
= *poff
;
1726 this->offset_
= orig_off
;
1728 *poff
= align_address(*poff
, this->addralign());
1730 addr
= this->set_section_list_addresses(&this->output_data_
, addr
, poff
,
1732 this->filesz_
= *poff
- orig_off
;
1736 uint64_t ret
= this->set_section_list_addresses(&this->output_bss_
, addr
,
1738 this->memsz_
= *poff
- orig_off
;
1740 // Ignore the file offset adjustments made by the BSS Output_data
1747 // Set the addresses and file offsets in a list of Output_data
1751 Output_segment::set_section_list_addresses(Output_data_list
* pdl
,
1752 uint64_t addr
, off_t
* poff
,
1753 unsigned int* pshndx
)
1755 off_t startoff
= *poff
;
1757 off_t off
= startoff
;
1758 for (Output_data_list::iterator p
= pdl
->begin();
1762 off
= align_address(off
, (*p
)->addralign());
1763 (*p
)->set_address_and_file_offset(addr
+ (off
- startoff
), off
);
1765 // Unless this is a PT_TLS segment, we want to ignore the size
1766 // of a SHF_TLS/SHT_NOBITS section. Such a section does not
1767 // affect the size of a PT_LOAD segment.
1768 if (this->type_
== elfcpp::PT_TLS
1769 || !(*p
)->is_section_flag_set(elfcpp::SHF_TLS
)
1770 || !(*p
)->is_section_type(elfcpp::SHT_NOBITS
))
1771 off
+= (*p
)->data_size();
1773 if ((*p
)->is_section())
1775 (*p
)->set_out_shndx(*pshndx
);
1781 return addr
+ (off
- startoff
);
1784 // For a non-PT_LOAD segment, set the offset from the sections, if
1788 Output_segment::set_offset()
1790 gold_assert(this->type_
!= elfcpp::PT_LOAD
);
1792 if (this->output_data_
.empty() && this->output_bss_
.empty())
1803 const Output_data
* first
;
1804 if (this->output_data_
.empty())
1805 first
= this->output_bss_
.front();
1807 first
= this->output_data_
.front();
1808 this->vaddr_
= first
->address();
1809 this->paddr_
= this->vaddr_
;
1810 this->offset_
= first
->offset();
1812 if (this->output_data_
.empty())
1816 const Output_data
* last_data
= this->output_data_
.back();
1817 this->filesz_
= (last_data
->address()
1818 + last_data
->data_size()
1822 const Output_data
* last
;
1823 if (this->output_bss_
.empty())
1824 last
= this->output_data_
.back();
1826 last
= this->output_bss_
.back();
1827 this->memsz_
= (last
->address()
1832 // Return the number of Output_sections in an Output_segment.
1835 Output_segment::output_section_count() const
1837 return (this->output_section_count_list(&this->output_data_
)
1838 + this->output_section_count_list(&this->output_bss_
));
1841 // Return the number of Output_sections in an Output_data_list.
1844 Output_segment::output_section_count_list(const Output_data_list
* pdl
) const
1846 unsigned int count
= 0;
1847 for (Output_data_list::const_iterator p
= pdl
->begin();
1851 if ((*p
)->is_section())
1857 // Write the segment data into *OPHDR.
1859 template<int size
, bool big_endian
>
1861 Output_segment::write_header(elfcpp::Phdr_write
<size
, big_endian
>* ophdr
)
1863 ophdr
->put_p_type(this->type_
);
1864 ophdr
->put_p_offset(this->offset_
);
1865 ophdr
->put_p_vaddr(this->vaddr_
);
1866 ophdr
->put_p_paddr(this->paddr_
);
1867 ophdr
->put_p_filesz(this->filesz_
);
1868 ophdr
->put_p_memsz(this->memsz_
);
1869 ophdr
->put_p_flags(this->flags_
);
1870 ophdr
->put_p_align(this->addralign());
1873 // Write the section headers into V.
1875 template<int size
, bool big_endian
>
1877 Output_segment::write_section_headers(const Layout
* layout
,
1878 const Stringpool
* secnamepool
,
1880 unsigned int *pshndx
1881 ACCEPT_SIZE_ENDIAN
) const
1883 // Every section that is attached to a segment must be attached to a
1884 // PT_LOAD segment, so we only write out section headers for PT_LOAD
1886 if (this->type_
!= elfcpp::PT_LOAD
)
1889 v
= this->write_section_headers_list
1890 SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
1891 layout
, secnamepool
, &this->output_data_
, v
, pshndx
1892 SELECT_SIZE_ENDIAN(size
, big_endian
));
1893 v
= this->write_section_headers_list
1894 SELECT_SIZE_ENDIAN_NAME(size
, big_endian
) (
1895 layout
, secnamepool
, &this->output_bss_
, v
, pshndx
1896 SELECT_SIZE_ENDIAN(size
, big_endian
));
1900 template<int size
, bool big_endian
>
1902 Output_segment::write_section_headers_list(const Layout
* layout
,
1903 const Stringpool
* secnamepool
,
1904 const Output_data_list
* pdl
,
1906 unsigned int* pshndx
1907 ACCEPT_SIZE_ENDIAN
) const
1909 const int shdr_size
= elfcpp::Elf_sizes
<size
>::shdr_size
;
1910 for (Output_data_list::const_iterator p
= pdl
->begin();
1914 if ((*p
)->is_section())
1916 const Output_section
* ps
= static_cast<const Output_section
*>(*p
);
1917 gold_assert(*pshndx
== ps
->out_shndx());
1918 elfcpp::Shdr_write
<size
, big_endian
> oshdr(v
);
1919 ps
->write_header(layout
, secnamepool
, &oshdr
);
1927 // Output_file methods.
1929 Output_file::Output_file(const General_options
& options
, Target
* target
)
1930 : options_(options
),
1932 name_(options
.output_file_name()),
1936 map_is_anonymous_(false)
1940 // Open the output file.
1943 Output_file::open(off_t file_size
)
1945 this->file_size_
= file_size
;
1947 // Unlink the file first; otherwise the open() may fail if the file
1948 // is busy (e.g. it's an executable that's currently being executed).
1950 // However, the linker may be part of a system where a zero-length
1951 // file is created for it to write to, with tight permissions (gcc
1952 // 2.95 did something like this). Unlinking the file would work
1953 // around those permission controls, so we only unlink if the file
1954 // has a non-zero size. We also unlink only regular files to avoid
1955 // trouble with directories/etc.
1957 // If we fail, continue; this command is merely a best-effort attempt
1958 // to improve the odds for open().
1960 // We let the name "-" mean "stdout"
1961 if (strcmp(this->name_
, "-") == 0)
1962 this->o_
= STDOUT_FILENO
;
1966 if (::stat(this->name_
, &s
) == 0 && s
.st_size
!= 0)
1967 unlink_if_ordinary(this->name_
);
1969 int mode
= parameters
->output_is_object() ? 0666 : 0777;
1970 int o
= ::open(this->name_
, O_RDWR
| O_CREAT
| O_TRUNC
, mode
);
1972 gold_fatal(_("%s: open: %s"), this->name_
, strerror(errno
));
1979 // Resize the output file.
1982 Output_file::resize(off_t file_size
)
1984 // If the mmap is mapping an anonymous memory buffer, this is easy:
1985 // just mremap to the new size. If it's mapping to a file, we want
1986 // to unmap to flush to the file, then remap after growing the file.
1987 if (this->map_is_anonymous_
)
1989 void* base
= ::mremap(this->base_
, this->file_size_
, file_size
,
1991 if (base
== MAP_FAILED
)
1992 gold_fatal(_("%s: mremap: %s"), this->name_
, strerror(errno
));
1993 this->base_
= static_cast<unsigned char*>(base
);
1994 this->file_size_
= file_size
;
1999 this->file_size_
= file_size
;
2004 // Map the file into memory.
2009 const int o
= this->o_
;
2011 // If the output file is not a regular file, don't try to mmap it;
2012 // instead, we'll mmap a block of memory (an anonymous buffer), and
2013 // then later write the buffer to the file.
2015 struct stat statbuf
;
2016 if (o
== STDOUT_FILENO
|| o
== STDERR_FILENO
2017 || ::fstat(o
, &statbuf
) != 0
2018 || !S_ISREG(statbuf
.st_mode
))
2020 this->map_is_anonymous_
= true;
2021 base
= ::mmap(NULL
, this->file_size_
, PROT_READ
| PROT_WRITE
,
2022 MAP_PRIVATE
| MAP_ANONYMOUS
, -1, 0);
2026 // Write out one byte to make the file the right size.
2027 if (::lseek(o
, this->file_size_
- 1, SEEK_SET
) < 0)
2028 gold_fatal(_("%s: lseek: %s"), this->name_
, strerror(errno
));
2030 if (::write(o
, &b
, 1) != 1)
2031 gold_fatal(_("%s: write: %s"), this->name_
, strerror(errno
));
2033 // Map the file into memory.
2034 this->map_is_anonymous_
= false;
2035 base
= ::mmap(NULL
, this->file_size_
, PROT_READ
| PROT_WRITE
,
2038 if (base
== MAP_FAILED
)
2039 gold_fatal(_("%s: mmap: %s"), this->name_
, strerror(errno
));
2040 this->base_
= static_cast<unsigned char*>(base
);
2043 // Unmap the file from memory.
2046 Output_file::unmap()
2048 if (::munmap(this->base_
, this->file_size_
) < 0)
2049 gold_error(_("%s: munmap: %s"), this->name_
, strerror(errno
));
2053 // Close the output file.
2056 Output_file::close()
2058 // If the map isn't file-backed, we need to write it now.
2059 if (this->map_is_anonymous_
)
2061 size_t bytes_to_write
= this->file_size_
;
2062 while (bytes_to_write
> 0)
2064 ssize_t bytes_written
= ::write(this->o_
, this->base_
, bytes_to_write
);
2065 if (bytes_written
== 0)
2066 gold_error(_("%s: write: unexpected 0 return-value"), this->name_
);
2067 else if (bytes_written
< 0)
2068 gold_error(_("%s: write: %s"), this->name_
, strerror(errno
));
2070 bytes_to_write
-= bytes_written
;
2075 // We don't close stdout or stderr
2076 if (this->o_
!= STDOUT_FILENO
&& this->o_
!= STDERR_FILENO
)
2077 if (::close(this->o_
) < 0)
2078 gold_error(_("%s: close: %s"), this->name_
, strerror(errno
));
2082 // Instantiate the templates we need. We could use the configure
2083 // script to restrict this to only the ones for implemented targets.
2085 #ifdef HAVE_TARGET_32_LITTLE
2088 Output_section::add_input_section
<32, false>(
2089 Sized_relobj
<32, false>* object
,
2091 const char* secname
,
2092 const elfcpp::Shdr
<32, false>& shdr
,
2093 unsigned int reloc_shndx
);
2096 #ifdef HAVE_TARGET_32_BIG
2099 Output_section::add_input_section
<32, true>(
2100 Sized_relobj
<32, true>* object
,
2102 const char* secname
,
2103 const elfcpp::Shdr
<32, true>& shdr
,
2104 unsigned int reloc_shndx
);
2107 #ifdef HAVE_TARGET_64_LITTLE
2110 Output_section::add_input_section
<64, false>(
2111 Sized_relobj
<64, false>* object
,
2113 const char* secname
,
2114 const elfcpp::Shdr
<64, false>& shdr
,
2115 unsigned int reloc_shndx
);
2118 #ifdef HAVE_TARGET_64_BIG
2121 Output_section::add_input_section
<64, true>(
2122 Sized_relobj
<64, true>* object
,
2124 const char* secname
,
2125 const elfcpp::Shdr
<64, true>& shdr
,
2126 unsigned int reloc_shndx
);
2129 #ifdef HAVE_TARGET_32_LITTLE
2131 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, false>;
2134 #ifdef HAVE_TARGET_32_BIG
2136 class Output_data_reloc
<elfcpp::SHT_REL
, false, 32, true>;
2139 #ifdef HAVE_TARGET_64_LITTLE
2141 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, false>;
2144 #ifdef HAVE_TARGET_64_BIG
2146 class Output_data_reloc
<elfcpp::SHT_REL
, false, 64, true>;
2149 #ifdef HAVE_TARGET_32_LITTLE
2151 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, false>;
2154 #ifdef HAVE_TARGET_32_BIG
2156 class Output_data_reloc
<elfcpp::SHT_REL
, true, 32, true>;
2159 #ifdef HAVE_TARGET_64_LITTLE
2161 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, false>;
2164 #ifdef HAVE_TARGET_64_BIG
2166 class Output_data_reloc
<elfcpp::SHT_REL
, true, 64, true>;
2169 #ifdef HAVE_TARGET_32_LITTLE
2171 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, false>;
2174 #ifdef HAVE_TARGET_32_BIG
2176 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 32, true>;
2179 #ifdef HAVE_TARGET_64_LITTLE
2181 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, false>;
2184 #ifdef HAVE_TARGET_64_BIG
2186 class Output_data_reloc
<elfcpp::SHT_RELA
, false, 64, true>;
2189 #ifdef HAVE_TARGET_32_LITTLE
2191 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, false>;
2194 #ifdef HAVE_TARGET_32_BIG
2196 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 32, true>;
2199 #ifdef HAVE_TARGET_64_LITTLE
2201 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, false>;
2204 #ifdef HAVE_TARGET_64_BIG
2206 class Output_data_reloc
<elfcpp::SHT_RELA
, true, 64, true>;
2209 #ifdef HAVE_TARGET_32_LITTLE
2211 class Output_data_got
<32, false>;
2214 #ifdef HAVE_TARGET_32_BIG
2216 class Output_data_got
<32, true>;
2219 #ifdef HAVE_TARGET_64_LITTLE
2221 class Output_data_got
<64, false>;
2224 #ifdef HAVE_TARGET_64_BIG
2226 class Output_data_got
<64, true>;
2229 } // End namespace gold.