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.