1 // readsyms.cc -- read input file symbols 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.
29 #include "dirsearch.h"
39 // Class read_symbols.
41 Read_symbols::~Read_symbols()
43 // The this_blocker_ and next_blocker_ pointers are passed on to the
47 // Return whether a Read_symbols task is runnable. We can read an
48 // ordinary input file immediately. For an archive specified using
49 // -l, we have to wait until the search path is complete.
51 Task::Is_runnable_type
52 Read_symbols::is_runnable(Workqueue*)
54 if (this->input_argument_->is_file()
55 && this->input_argument_->file().may_need_search()
56 && this->dirpath_.token().is_blocked())
62 // Return a Task_locker for a Read_symbols task. We don't need any
66 Read_symbols::locks(Workqueue*)
71 // Run a Read_symbols task. This is where we actually read the
72 // symbols and relocations.
75 Read_symbols::run(Workqueue* workqueue)
77 if (this->input_argument_->is_group())
79 gold_assert(this->input_group_ == NULL);
80 this->do_group(workqueue);
84 Input_file* input_file = new Input_file(&this->input_argument_->file());
85 if (!input_file->open(this->options_, this->dirpath_))
88 // Read enough of the file to pick up the entire ELF header.
90 off_t filesize = input_file->file().filesize();
94 gold_error(_("%s: file is empty"),
95 input_file->file().filename().c_str());
99 unsigned char ehdr_buf[elfcpp::Elf_sizes<64>::ehdr_size];
101 int read_size = elfcpp::Elf_sizes<64>::ehdr_size;
102 if (filesize < read_size)
103 read_size = filesize;
105 input_file->file().read(0, read_size, ehdr_buf);
109 static unsigned char elfmagic[4] =
111 elfcpp::ELFMAG0, elfcpp::ELFMAG1,
112 elfcpp::ELFMAG2, elfcpp::ELFMAG3
114 if (memcmp(ehdr_buf, elfmagic, 4) == 0)
116 // This is an ELF object.
118 Object* obj = make_elf_object(input_file->filename(),
119 input_file, 0, ehdr_buf, read_size);
123 // We don't have a way to record a non-archive in an input
124 // group. If this is an ordinary object file, we can't
125 // include it more than once anyhow. If this is a dynamic
126 // object, then including it a second time changes nothing.
127 if (this->input_group_ != NULL && !obj->is_dynamic())
129 gold_error(_("%s: ordinary object found in input group"),
134 Read_symbols_data* sd = new Read_symbols_data;
135 obj->read_symbols(sd);
136 workqueue->queue_front(new Add_symbols(this->input_objects_,
137 this->symtab_, this->layout_,
140 this->next_blocker_));
142 // Opening the file locked it, so now we need to unlock it.
143 input_file->file().unlock();
149 if (read_size >= Archive::sarmag)
151 if (memcmp(ehdr_buf, Archive::armag, Archive::sarmag) == 0)
153 // This is an archive.
154 Archive* arch = new Archive(this->input_argument_->file().name(),
157 workqueue->queue(new Add_archive_symbols(this->symtab_,
159 this->input_objects_,
163 this->next_blocker_));
168 // Try to parse this file as a script.
169 if (read_input_script(workqueue, this->options_, this->symtab_,
170 this->layout_, this->dirpath_, this->input_objects_,
171 this->input_group_, this->input_argument_, input_file,
172 ehdr_buf, read_size, this->this_blocker_,
173 this->next_blocker_))
176 // Here we have to handle any other input file types we need.
177 gold_error(_("%s: not an object or archive"),
178 input_file->file().filename().c_str());
181 // Handle a group. We need to walk through the arguments over and
182 // over until we don't see any new undefined symbols. We do this by
183 // setting off Read_symbols Tasks as usual, but recording the archive
184 // entries instead of deleting them. We also start a Finish_group
185 // Task which runs after we've read all the symbols. In that task we
186 // process the archives in a loop until we are done.
189 Read_symbols::do_group(Workqueue* workqueue)
191 Input_group* input_group = new Input_group();
193 const Input_file_group* group = this->input_argument_->group();
194 Task_token* this_blocker = this->this_blocker_;
195 for (Input_file_group::const_iterator p = group->begin();
199 const Input_argument* arg = &*p;
200 gold_assert(arg->is_file());
202 Task_token* next_blocker = new Task_token();
203 next_blocker->add_blocker();
204 workqueue->queue(new Read_symbols(this->options_, this->input_objects_,
205 this->symtab_, this->layout_,
206 this->dirpath_, arg, input_group,
207 this_blocker, next_blocker));
208 this_blocker = next_blocker;
211 const int saw_undefined = this->symtab_->saw_undefined();
212 workqueue->queue(new Finish_group(this->input_objects_,
218 this->next_blocker_));
221 // Class Add_symbols.
223 Add_symbols::~Add_symbols()
225 if (this->this_blocker_ != NULL)
226 delete this->this_blocker_;
227 // next_blocker_ is deleted by the task associated with the next
231 // We are blocked by this_blocker_. We block next_blocker_. We also
234 Task::Is_runnable_type
235 Add_symbols::is_runnable(Workqueue*)
237 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
239 if (this->object_->is_locked())
244 class Add_symbols::Add_symbols_locker : public Task_locker
247 Add_symbols_locker(Task_token& token, Workqueue* workqueue,
249 : blocker_(token, workqueue), objlock_(*object)
253 Task_locker_block blocker_;
254 Task_locker_obj<Object> objlock_;
258 Add_symbols::locks(Workqueue* workqueue)
260 return new Add_symbols_locker(*this->next_blocker_, workqueue,
264 // Add the symbols in the object to the symbol table.
267 Add_symbols::run(Workqueue*)
269 if (!this->input_objects_->add_object(this->object_))
271 // FIXME: We need to close the descriptor here.
272 delete this->object_;
276 this->object_->layout(this->symtab_, this->layout_, this->sd_);
277 this->object_->add_symbols(this->symtab_, this->sd_);
283 // Class Finish_group.
285 Finish_group::~Finish_group()
287 if (this->this_blocker_ != NULL)
288 delete this->this_blocker_;
289 // next_blocker_ is deleted by the task associated with the next
290 // input file following the group.
293 // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
295 Task::Is_runnable_type
296 Finish_group::is_runnable(Workqueue*)
298 if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
304 Finish_group::locks(Workqueue* workqueue)
306 return new Task_locker_block(*this->next_blocker_, workqueue);
309 // Loop over the archives until there are no new undefined symbols.
312 Finish_group::run(Workqueue*)
314 int saw_undefined = this->saw_undefined_;
315 while (saw_undefined != this->symtab_->saw_undefined())
317 saw_undefined = this->symtab_->saw_undefined();
319 for (Input_group::const_iterator p = this->input_group_->begin();
320 p != this->input_group_->end();
323 Task_lock_obj<Archive> tl(**p);
325 (*p)->add_symbols(this->symtab_, this->layout_,
326 this->input_objects_);
330 // Delete all the archives now that we no longer need them.
331 for (Input_group::const_iterator p = this->input_group_->begin();
332 p != this->input_group_->end();
335 delete this->input_group_;
338 } // End namespace gold.