1 // archive.cc -- archive support for gold
3 // Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
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.
29 #include "libiberty.h"
30 #include "filenames.h"
45 // The header of an entry in the archive. This is all readable text,
46 // padded with spaces where necesary. If the contents of an archive
47 // are all text file, the entire archive is readable.
49 struct Archive::Archive_header
53 // The file modification time.
55 // The user's UID in decimal.
57 // The user's GID in decimal.
59 // The file mode in octal.
61 // The file size in decimal.
63 // The final magic code.
67 // Class Archive static variables.
68 unsigned int Archive::total_archives;
69 unsigned int Archive::total_members;
70 unsigned int Archive::total_members_loaded;
74 const char Archive::armag[sarmag] =
76 '!', '<', 'a', 'r', 'c', 'h', '>', '\n'
79 const char Archive::armagt[sarmag] =
81 '!', '<', 't', 'h', 'i', 'n', '>', '\n'
84 const char Archive::arfmag[2] = { '`', '\n' };
86 Archive::Archive(const std::string& name, Input_file* input_file,
87 bool is_thin_archive, Dirsearch* dirpath, Task* task)
88 : name_(name), input_file_(input_file), armap_(), armap_names_(),
89 extended_names_(), armap_checked_(), seen_offsets_(), members_(),
90 is_thin_archive_(is_thin_archive), included_member_(false),
91 nested_archives_(), dirpath_(dirpath), task_(task), num_members_(0)
94 parameters->options().check_excluded_libs(input_file->found_name());
97 // Set up the archive: read the symbol map and the extended name
103 // We need to ignore empty archives.
104 if (this->input_file_->file().filesize() == sarmag)
107 // The first member of the archive should be the symbol table.
108 std::string armap_name;
109 section_size_type armap_size =
110 convert_to_section_size_type(this->read_header(sarmag, false,
113 if (armap_name.empty())
115 this->read_armap(sarmag + sizeof(Archive_header), armap_size);
116 off = sarmag + sizeof(Archive_header) + armap_size;
118 else if (!this->input_file_->options().whole_archive())
119 gold_error(_("%s: no archive symbol table (run ranlib)"),
120 this->name().c_str());
122 // See if there is an extended name table. We cache these views
123 // because it is likely that we will want to read the following
124 // header in the add_symbols routine.
128 section_size_type extended_size =
129 convert_to_section_size_type(this->read_header(off, true, &xname, NULL));
132 const unsigned char* p = this->get_view(off + sizeof(Archive_header),
133 extended_size, false, true);
134 const char* px = reinterpret_cast<const char*>(p);
135 this->extended_names_.assign(px, extended_size);
137 bool preread_syms = (parameters->options().threads()
138 && parameters->options().preread_archive_symbols());
139 #ifndef ENABLE_THREADS
140 preread_syms = false;
142 if (parameters->options().has_plugins())
143 preread_syms = false;
146 this->read_all_symbols();
149 // Unlock any nested archives.
152 Archive::unlock_nested_archives()
154 for (Nested_archive_table::iterator p = this->nested_archives_.begin();
155 p != this->nested_archives_.end();
158 p->second->unlock(this->task_);
162 // Read the archive symbol map.
165 Archive::read_armap(off_t start, section_size_type size)
167 // To count the total number of archive members, we'll just count
168 // the number of times the file offset changes. Since most archives
169 // group the symbols in the armap by object, this ought to give us
170 // an accurate count.
171 off_t last_seen_offset = -1;
173 // Read in the entire armap.
174 const unsigned char* p = this->get_view(start, size, true, false);
176 // Numbers in the armap are always big-endian.
177 const elfcpp::Elf_Word* pword = reinterpret_cast<const elfcpp::Elf_Word*>(p);
178 unsigned int nsyms = elfcpp::Swap<32, true>::readval(pword);
181 // Note that the addition is in units of sizeof(elfcpp::Elf_Word).
182 const char* pnames = reinterpret_cast<const char*>(pword + nsyms);
183 section_size_type names_size =
184 reinterpret_cast<const char*>(p) + size - pnames;
185 this->armap_names_.assign(pnames, names_size);
187 this->armap_.resize(nsyms);
189 section_offset_type name_offset = 0;
190 for (unsigned int i = 0; i < nsyms; ++i)
192 this->armap_[i].name_offset = name_offset;
193 this->armap_[i].file_offset = elfcpp::Swap<32, true>::readval(pword);
194 name_offset += strlen(pnames + name_offset) + 1;
196 if (this->armap_[i].file_offset != last_seen_offset)
198 last_seen_offset = this->armap_[i].file_offset;
199 ++this->num_members_;
203 if (static_cast<section_size_type>(name_offset) > names_size)
204 gold_error(_("%s: bad archive symbol table names"),
205 this->name().c_str());
207 // This array keeps track of which symbols are for archive elements
208 // which we have already included in the link.
209 this->armap_checked_.resize(nsyms);
212 // Read the header of an archive member at OFF. Fail if something
213 // goes wrong. Return the size of the member. Set *PNAME to the name
217 Archive::read_header(off_t off, bool cache, std::string* pname,
220 const unsigned char* p = this->get_view(off, sizeof(Archive_header), true,
222 const Archive_header* hdr = reinterpret_cast<const Archive_header*>(p);
223 return this->interpret_header(hdr, off, pname, nested_off);
226 // Interpret the header of HDR, the header of the archive member at
227 // file offset OFF. Fail if something goes wrong. Return the size of
228 // the member. Set *PNAME to the name of the member.
231 Archive::interpret_header(const Archive_header* hdr, off_t off,
232 std::string* pname, off_t* nested_off) const
234 if (memcmp(hdr->ar_fmag, arfmag, sizeof arfmag) != 0)
236 gold_error(_("%s: malformed archive header at %zu"),
237 this->name().c_str(), static_cast<size_t>(off));
238 return this->input_file_->file().filesize() - off;
241 const int size_string_size = sizeof hdr->ar_size;
242 char size_string[size_string_size + 1];
243 memcpy(size_string, hdr->ar_size, size_string_size);
244 char* ps = size_string + size_string_size;
245 while (ps[-1] == ' ')
251 off_t member_size = strtol(size_string, &end, 10);
254 || (member_size == LONG_MAX && errno == ERANGE))
256 gold_error(_("%s: malformed archive header size at %zu"),
257 this->name().c_str(), static_cast<size_t>(off));
258 return this->input_file_->file().filesize() - off;
261 if (hdr->ar_name[0] != '/')
263 const char* name_end = strchr(hdr->ar_name, '/');
265 || name_end - hdr->ar_name >= static_cast<int>(sizeof hdr->ar_name))
267 gold_error(_("%s: malformed archive header name at %zu"),
268 this->name().c_str(), static_cast<size_t>(off));
269 return this->input_file_->file().filesize() - off;
271 pname->assign(hdr->ar_name, name_end - hdr->ar_name);
272 if (nested_off != NULL)
275 else if (hdr->ar_name[1] == ' ')
277 // This is the symbol table.
280 else if (hdr->ar_name[1] == '/')
282 // This is the extended name table.
283 pname->assign(1, '/');
288 long x = strtol(hdr->ar_name + 1, &end, 10);
291 y = strtol(end + 1, &end, 10);
294 || (x == LONG_MAX && errno == ERANGE)
295 || static_cast<size_t>(x) >= this->extended_names_.size())
297 gold_error(_("%s: bad extended name index at %zu"),
298 this->name().c_str(), static_cast<size_t>(off));
299 return this->input_file_->file().filesize() - off;
302 const char* name = this->extended_names_.data() + x;
303 const char* name_end = strchr(name, '\n');
304 if (static_cast<size_t>(name_end - name) > this->extended_names_.size()
305 || name_end[-1] != '/')
307 gold_error(_("%s: bad extended name entry at header %zu"),
308 this->name().c_str(), static_cast<size_t>(off));
309 return this->input_file_->file().filesize() - off;
311 pname->assign(name, name_end - 1 - name);
312 if (nested_off != NULL)
319 // An archive member iterator.
321 class Archive::const_iterator
324 // The header of an archive member. This is what this iterator
328 // The name of the member.
330 // The file offset of the member.
332 // The file offset of a nested archive member.
334 // The size of the member.
338 const_iterator(Archive* archive, off_t off)
339 : archive_(archive), off_(off)
340 { this->read_next_header(); }
344 { return this->header_; }
348 { return &this->header_; }
353 if (this->off_ == this->archive_->file().filesize())
355 this->off_ += sizeof(Archive_header);
356 if (!this->archive_->is_thin_archive())
357 this->off_ += this->header_.size;
358 if ((this->off_ & 1) != 0)
360 this->read_next_header();
367 const_iterator ret = *this;
373 operator==(const const_iterator p) const
374 { return this->off_ == p->off; }
377 operator!=(const const_iterator p) const
378 { return this->off_ != p->off; }
384 // The underlying archive.
386 // The current offset in the file.
388 // The current archive header.
392 // Read the next archive header.
395 Archive::const_iterator::read_next_header()
397 off_t filesize = this->archive_->file().filesize();
400 if (filesize - this->off_ < static_cast<off_t>(sizeof(Archive_header)))
402 if (filesize != this->off_)
404 gold_error(_("%s: short archive header at %zu"),
405 this->archive_->filename().c_str(),
406 static_cast<size_t>(this->off_));
407 this->off_ = filesize;
409 this->header_.off = filesize;
413 unsigned char buf[sizeof(Archive_header)];
414 this->archive_->file().read(this->off_, sizeof(Archive_header), buf);
416 const Archive_header* hdr = reinterpret_cast<const Archive_header*>(buf);
418 this->archive_->interpret_header(hdr, this->off_, &this->header_.name,
419 &this->header_.nested_off);
420 this->header_.off = this->off_;
422 // Skip special members.
423 if (!this->header_.name.empty() && this->header_.name != "/")
426 this->off_ += sizeof(Archive_header) + this->header_.size;
427 if ((this->off_ & 1) != 0)
434 Archive::const_iterator
437 return Archive::const_iterator(this, sarmag);
442 Archive::const_iterator
445 return Archive::const_iterator(this, this->input_file_->file().filesize());
448 // Get the file and offset for an archive member, which may be an
449 // external member of a thin archive. Set *INPUT_FILE to the
450 // file containing the actual member, *MEMOFF to the offset
451 // within that file (0 if not a nested archive), and *MEMBER_NAME
452 // to the name of the archive member. Return TRUE on success.
455 Archive::get_file_and_offset(off_t off, Input_file** input_file, off_t* memoff,
456 off_t* memsize, std::string* member_name)
460 *memsize = this->read_header(off, false, member_name, &nested_off);
462 *input_file = this->input_file_;
463 *memoff = off + static_cast<off_t>(sizeof(Archive_header));
465 if (!this->is_thin_archive_)
468 // Adjust a relative pathname so that it is relative
469 // to the directory containing the archive.
470 if (!IS_ABSOLUTE_PATH(member_name->c_str()))
472 const char* arch_path = this->filename().c_str();
473 const char* basename = lbasename(arch_path);
474 if (basename > arch_path)
475 member_name->replace(0, 0,
476 this->filename().substr(0, basename - arch_path));
481 // This is a member of a nested archive. Open the containing
482 // archive if we don't already have it open, then do a recursive
483 // call to include the member from that archive.
485 Nested_archive_table::const_iterator p =
486 this->nested_archives_.find(*member_name);
487 if (p != this->nested_archives_.end())
491 Input_file_argument* input_file_arg =
492 new Input_file_argument(member_name->c_str(),
493 Input_file_argument::INPUT_FILE_TYPE_FILE,
494 "", false, parameters->options());
495 *input_file = new Input_file(input_file_arg);
497 if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
499 arch = new Archive(*member_name, *input_file, false, this->dirpath_,
502 std::pair<Nested_archive_table::iterator, bool> ins =
503 this->nested_archives_.insert(std::make_pair(*member_name, arch));
504 gold_assert(ins.second);
506 return arch->get_file_and_offset(nested_off, input_file, memoff,
507 memsize, member_name);
510 // This is an external member of a thin archive. Open the
511 // file as a regular relocatable object file.
512 Input_file_argument* input_file_arg =
513 new Input_file_argument(member_name->c_str(),
514 Input_file_argument::INPUT_FILE_TYPE_FILE,
515 "", false, this->input_file_->options());
516 *input_file = new Input_file(input_file_arg);
518 if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
522 *memsize = (*input_file)->file().filesize();
526 // Return an ELF object for the member at offset OFF. If the ELF
527 // object has an unsupported target type, set *PUNCONFIGURED to true
531 Archive::get_elf_object_for_member(off_t off, bool* punconfigured)
533 *punconfigured = false;
535 Input_file* input_file;
538 std::string member_name;
539 if (!this->get_file_and_offset(off, &input_file, &memoff, &memsize,
543 if (parameters->options().has_plugins())
545 Object* obj = parameters->options().plugins()->claim_file(input_file,
550 // The input file was claimed by a plugin, and its symbols
551 // have been provided by the plugin.
556 const unsigned char* ehdr;
558 if (!is_elf_object(input_file, memoff, &ehdr, &read_size))
560 gold_error(_("%s: member at %zu is not an ELF object"),
561 this->name().c_str(), static_cast<size_t>(off));
565 Object *obj = make_elf_object((std::string(this->input_file_->filename())
566 + "(" + member_name + ")"),
567 input_file, memoff, ehdr, read_size,
571 obj->set_no_export(this->no_export());
575 // Read the symbols from all the archive members in the link.
578 Archive::read_all_symbols()
580 for (Archive::const_iterator p = this->begin();
583 this->read_symbols(p->off);
586 // Read the symbols from an archive member in the link. OFF is the file
587 // offset of the member header.
590 Archive::read_symbols(off_t off)
593 Object* obj = this->get_elf_object_for_member(off, &dummy);
598 Read_symbols_data* sd = new Read_symbols_data;
599 obj->read_symbols(sd);
600 Archive_member member(obj, sd);
601 this->members_[off] = member;
604 // Select members from the archive and add them to the link. We walk
605 // through the elements in the archive map, and look each one up in
606 // the symbol table. If it exists as a strong undefined symbol, we
607 // pull in the corresponding element. We have to do this in a loop,
608 // since pulling in one element may create new undefined symbols which
609 // may be satisfied by other objects in the archive. Return true in
610 // the normal case, false if the first member we tried to add from
611 // this archive had an incompatible target.
614 Archive::add_symbols(Symbol_table* symtab, Layout* layout,
615 Input_objects* input_objects, Mapfile* mapfile)
617 ++Archive::total_archives;
619 if (this->input_file_->options().whole_archive())
620 return this->include_all_members(symtab, layout, input_objects,
623 Archive::total_members += this->num_members_;
625 input_objects->archive_start(this);
627 const size_t armap_size = this->armap_.size();
629 // This is a quick optimization, since we usually see many symbols
630 // in a row with the same offset. last_seen_offset holds the last
631 // offset we saw that was present in the seen_offsets_ set.
632 off_t last_seen_offset = -1;
634 // Track which symbols in the symbol table we've already found to be
638 size_t tmpbuflen = 0;
639 bool added_new_object;
642 added_new_object = false;
643 for (size_t i = 0; i < armap_size; ++i)
645 if (this->armap_checked_[i])
647 if (this->armap_[i].file_offset == last_seen_offset)
649 this->armap_checked_[i] = true;
652 if (this->seen_offsets_.find(this->armap_[i].file_offset)
653 != this->seen_offsets_.end())
655 this->armap_checked_[i] = true;
656 last_seen_offset = this->armap_[i].file_offset;
660 const char* sym_name = (this->armap_names_.data()
661 + this->armap_[i].name_offset);
663 // In an object file, and therefore in an archive map, an
664 // '@' in the name separates the symbol name from the
665 // version name. If there are two '@' characters, this is
666 // the default version.
667 const char* ver = strchr(sym_name, '@');
671 size_t symlen = ver - sym_name;
672 if (symlen + 1 > tmpbuflen)
674 tmpbuf = static_cast<char*>(realloc(tmpbuf, symlen + 1));
675 tmpbuflen = symlen + 1;
677 memcpy(tmpbuf, sym_name, symlen);
678 tmpbuf[symlen] = '\0';
689 Symbol* sym = symtab->lookup(sym_name, ver);
693 || !sym->is_undefined()
694 || sym->binding() == elfcpp::STB_WEAK))
695 sym = symtab->lookup(sym_name, NULL);
699 // Check whether the symbol was named in a -u option.
700 if (!parameters->options().is_undefined(sym_name))
703 else if (!sym->is_undefined())
705 this->armap_checked_[i] = true;
708 else if (sym->binding() == elfcpp::STB_WEAK)
711 // We want to include this object in the link.
712 last_seen_offset = this->armap_[i].file_offset;
713 this->seen_offsets_.insert(last_seen_offset);
714 this->armap_checked_[i] = true;
722 if (!this->include_member(symtab, layout, input_objects,
723 last_seen_offset, mapfile, sym,
731 added_new_object = true;
734 while (added_new_object);
739 input_objects->archive_stop(this);
744 // Include all the archive members in the link. This is for --whole-archive.
747 Archive::include_all_members(Symbol_table* symtab, Layout* layout,
748 Input_objects* input_objects, Mapfile* mapfile)
750 input_objects->archive_start(this);
752 if (this->members_.size() > 0)
754 std::map<off_t, Archive_member>::const_iterator p;
755 for (p = this->members_.begin();
756 p != this->members_.end();
759 if (!this->include_member(symtab, layout, input_objects, p->first,
760 mapfile, NULL, "--whole-archive"))
762 ++Archive::total_members;
767 for (Archive::const_iterator p = this->begin();
771 if (!this->include_member(symtab, layout, input_objects, p->off,
772 mapfile, NULL, "--whole-archive"))
774 ++Archive::total_members;
778 input_objects->archive_stop(this);
783 // Return the number of members in the archive. This is only used for
787 Archive::count_members()
790 for (Archive::const_iterator p = this->begin();
797 // Include an archive member in the link. OFF is the file offset of
798 // the member header. WHY is the reason we are including this member.
799 // Return true if we added the member or if we had an error, return
800 // false if this was the first member we tried to add from this
801 // archive and it had an incompatible format.
804 Archive::include_member(Symbol_table* symtab, Layout* layout,
805 Input_objects* input_objects, off_t off,
806 Mapfile* mapfile, Symbol* sym, const char* why)
808 ++Archive::total_members_loaded;
810 std::map<off_t, Archive_member>::const_iterator p = this->members_.find(off);
811 if (p != this->members_.end())
813 Object *obj = p->second.obj_;
815 Read_symbols_data *sd = p->second.sd_;
817 mapfile->report_include_archive_member(obj->name(), sym, why);
818 if (input_objects->add_object(obj))
820 obj->layout(symtab, layout, sd);
821 obj->add_symbols(symtab, sd, layout);
822 this->included_member_ = true;
829 Object* obj = this->get_elf_object_for_member(off, &unconfigured);
831 if (!this->included_member_
832 && this->searched_for()
845 mapfile->report_include_archive_member(obj->name(), sym, why);
847 Pluginobj* pluginobj = obj->pluginobj();
848 if (pluginobj != NULL)
850 pluginobj->add_symbols(symtab, NULL, layout);
851 this->included_member_ = true;
855 if (!input_objects->add_object(obj))
859 Read_symbols_data sd;
860 obj->read_symbols(&sd);
861 obj->layout(symtab, layout, &sd);
862 obj->add_symbols(symtab, &sd, layout);
864 // If this is an external member of a thin archive, unlock the file
865 // for the next task.
866 if (obj->offset() == 0)
867 obj->unlock(this->task_);
869 this->included_member_ = true;
875 // Print statistical information to stderr. This is used for --stats.
878 Archive::print_stats()
880 fprintf(stderr, _("%s: archive libraries: %u\n"),
881 program_name, Archive::total_archives);
882 fprintf(stderr, _("%s: total archive members: %u\n"),
883 program_name, Archive::total_members);
884 fprintf(stderr, _("%s: loaded archive members: %u\n"),
885 program_name, Archive::total_members_loaded);
888 // Add_archive_symbols methods.
890 Add_archive_symbols::~Add_archive_symbols()
892 if (this->this_blocker_ != NULL)
893 delete this->this_blocker_;
894 // next_blocker_ is deleted by the task associated with the next
898 // Return whether we can add the archive symbols. We are blocked by
899 // this_blocker_. We block next_blocker_. We also lock the file.
902 Add_archive_symbols::is_runnable()
904 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
905 return this->this_blocker_;
910 Add_archive_symbols::locks(Task_locker* tl)
912 tl->add(this, this->next_blocker_);
913 tl->add(this, this->archive_->token());
917 Add_archive_symbols::run(Workqueue* workqueue)
919 bool added = this->archive_->add_symbols(this->symtab_, this->layout_,
920 this->input_objects_,
922 this->archive_->unlock_nested_archives();
924 this->archive_->release();
925 this->archive_->clear_uncached_views();
929 // This archive holds object files which are incompatible with
931 Read_symbols::incompatible_warning(this->input_argument_,
932 this->archive_->input_file());
933 Read_symbols::requeue(workqueue, this->input_objects_, this->symtab_,
934 this->layout_, this->dirpath_, this->dirindex_,
935 this->mapfile_, this->input_argument_,
936 this->input_group_, this->next_blocker_);
937 delete this->archive_;
941 if (this->input_group_ != NULL)
942 this->input_group_->add_archive(this->archive_);
945 // We no longer need to know about this archive.
946 delete this->archive_;
947 this->archive_ = NULL;
951 } // End namespace gold.