1 // plugin.c -- plugin manager for gold -*- C++ -*-
3 // Copyright 2008 Free Software Foundation, Inc.
4 // Written by Cary Coutant <ccoutant@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.
31 #include "parameters.h"
47 // The linker's exported interfaces.
52 static enum ld_plugin_status
53 register_claim_file(ld_plugin_claim_file_handler handler
);
55 static enum ld_plugin_status
56 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler
);
58 static enum ld_plugin_status
59 register_cleanup(ld_plugin_cleanup_handler handler
);
61 static enum ld_plugin_status
62 add_symbols(void *handle
, int nsyms
, const struct ld_plugin_symbol
*syms
);
64 static enum ld_plugin_status
65 get_symbols(const void *handle
, int nsyms
, struct ld_plugin_symbol
*syms
);
67 static enum ld_plugin_status
68 add_input_file(char *pathname
);
70 static enum ld_plugin_status
71 message(int level
, char *format
, ...);
75 #endif // ENABLE_PLUGINS
77 static Pluginobj
* make_sized_plugin_object(Input_file
* input_file
,
82 // Load one plugin library.
89 std::vector
<std::string
> args
;
91 // Parse the filename and arguments, each separated by commas.
92 // FIXME: Temporarily allowing semicolon as an argument separator
93 // so args can be passed through gcc's -Wl,... option, which
94 // breaks arguments at the commas.
95 const char* p
= this->args_
;
96 int n
= strcspn(p
, ",;");
97 filename
.assign(p
, n
);
99 while (*p
== ',' || *p
== ';')
102 n
= strcspn(p
, ",;");
103 args
.push_back(std::string(p
, n
));
107 // Load the plugin library.
108 // FIXME: Look for the library in standard locations.
109 this->handle_
= dlopen(filename
.c_str(), RTLD_NOW
);
110 if (this->handle_
== NULL
)
112 gold_error(_("%s: could not load plugin library"), filename
.c_str());
116 // Find the plugin's onload entry point.
117 ld_plugin_onload onload
= reinterpret_cast<ld_plugin_onload
>
118 (dlsym(this->handle_
, "onload"));
121 gold_error(_("%s: could not find onload entry point"), filename
.c_str());
125 // Get the linker's version number.
126 const char* ver
= get_version_string();
129 sscanf(ver
, "%d.%d", &major
, &minor
);
131 // Allocate and populate a transfer vector.
132 const int tv_fixed_size
= 11;
133 int tv_size
= args
.size() + tv_fixed_size
;
134 ld_plugin_tv
*tv
= new ld_plugin_tv
[tv_size
];
137 tv
[i
].tv_tag
= LDPT_API_VERSION
;
138 tv
[i
].tv_u
.tv_val
= LD_PLUGIN_API_VERSION
;
141 tv
[i
].tv_tag
= LDPT_GOLD_VERSION
;
142 tv
[i
].tv_u
.tv_val
= major
* 100 + minor
;
145 tv
[i
].tv_tag
= LDPT_LINKER_OUTPUT
;
146 if (parameters
->options().relocatable())
147 tv
[i
].tv_u
.tv_val
= LDPO_REL
;
148 else if (parameters
->options().shared())
149 tv
[i
].tv_u
.tv_val
= LDPO_DYN
;
151 tv
[i
].tv_u
.tv_val
= LDPO_EXEC
;
153 for (unsigned int j
= 0; j
< args
.size(); ++j
)
156 tv
[i
].tv_tag
= LDPT_OPTION
;
157 tv
[i
].tv_u
.tv_string
= args
[j
].c_str();
161 tv
[i
].tv_tag
= LDPT_REGISTER_CLAIM_FILE_HOOK
;
162 tv
[i
].tv_u
.tv_register_claim_file
= register_claim_file
;
165 tv
[i
].tv_tag
= LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK
;
166 tv
[i
].tv_u
.tv_register_all_symbols_read
= register_all_symbols_read
;
169 tv
[i
].tv_tag
= LDPT_REGISTER_CLEANUP_HOOK
;
170 tv
[i
].tv_u
.tv_register_cleanup
= register_cleanup
;
173 tv
[i
].tv_tag
= LDPT_ADD_SYMBOLS
;
174 tv
[i
].tv_u
.tv_add_symbols
= add_symbols
;
177 tv
[i
].tv_tag
= LDPT_GET_SYMBOLS
;
178 tv
[i
].tv_u
.tv_get_symbols
= get_symbols
;
181 tv
[i
].tv_tag
= LDPT_ADD_INPUT_FILE
;
182 tv
[i
].tv_u
.tv_add_input_file
= add_input_file
;
185 tv
[i
].tv_tag
= LDPT_MESSAGE
;
186 tv
[i
].tv_u
.tv_message
= message
;
189 tv
[i
].tv_tag
= LDPT_NULL
;
190 tv
[i
].tv_u
.tv_val
= 0;
192 gold_assert(i
== tv_size
- 1);
194 // Call the onload entry point.
198 #endif // ENABLE_PLUGINS
201 // Call the plugin claim-file handler.
204 Plugin::claim_file(struct ld_plugin_input_file
*plugin_input_file
)
208 if (this->claim_file_handler_
!= NULL
)
210 (*this->claim_file_handler_
)(plugin_input_file
, &claimed
);
217 // Call the all-symbols-read handler.
220 Plugin::all_symbols_read()
222 if (this->all_symbols_read_handler_
!= NULL
)
223 (*this->all_symbols_read_handler_
)();
226 // Call the cleanup handler.
231 if (this->cleanup_handler_
!= NULL
)
232 (*this->cleanup_handler_
)();
235 // Plugin_manager methods.
237 Plugin_manager::~Plugin_manager()
239 for (Plugin_list::iterator p
= this->plugins_
.begin();
240 p
!= this->plugins_
.end();
243 this->plugins_
.clear();
244 for (Object_list::iterator obj
= this->objects_
.begin();
245 obj
!= this->objects_
.end();
248 this->objects_
.clear();
251 // Load all plugin libraries.
254 Plugin_manager::load_plugins()
256 for (this->current_
= this->plugins_
.begin();
257 this->current_
!= this->plugins_
.end();
259 (*this->current_
)->load();
262 // Call the plugin claim-file handlers in turn to see if any claim the file.
265 Plugin_manager::claim_file(Input_file
* input_file
, off_t offset
,
268 if (this->in_replacement_phase_
)
271 unsigned int handle
= this->objects_
.size();
272 this->input_file_
= input_file
;
273 this->plugin_input_file_
.name
= input_file
->filename().c_str();
274 this->plugin_input_file_
.fd
= input_file
->file().descriptor();
275 this->plugin_input_file_
.offset
= offset
;
276 this->plugin_input_file_
.filesize
= filesize
;
277 this->plugin_input_file_
.handle
= reinterpret_cast<void*>(handle
);
279 for (this->current_
= this->plugins_
.begin();
280 this->current_
!= this->plugins_
.end();
283 if ((*this->current_
)->claim_file(&this->plugin_input_file_
))
285 if (this->objects_
.size() <= handle
)
287 gold_error(_("%s: plugin claimed the file "
288 "but did not provide any symbols"),
289 this->plugin_input_file_
.name
);
292 return this->objects_
[handle
];
299 // Call the all-symbols-read handlers.
302 Plugin_manager::all_symbols_read(Workqueue
* workqueue
,
303 Input_objects
* input_objects
,
304 Symbol_table
* symtab
, Layout
* layout
,
305 Dirsearch
* dirpath
, Mapfile
* mapfile
,
306 Task_token
** last_blocker
)
308 this->in_replacement_phase_
= true;
309 this->workqueue_
= workqueue
;
310 this->input_objects_
= input_objects
;
311 this->symtab_
= symtab
;
312 this->layout_
= layout
;
313 this->dirpath_
= dirpath
;
314 this->mapfile_
= mapfile
;
315 this->this_blocker_
= NULL
;
317 for (this->current_
= this->plugins_
.begin();
318 this->current_
!= this->plugins_
.end();
320 (*this->current_
)->all_symbols_read();
322 *last_blocker
= this->this_blocker_
;
325 // Call the cleanup handlers.
328 Plugin_manager::cleanup()
330 for (this->current_
= this->plugins_
.begin();
331 this->current_
!= this->plugins_
.end();
333 (*this->current_
)->cleanup();
336 // Make a new Pluginobj object. This is called when the plugin calls
337 // the add_symbols API.
340 Plugin_manager::make_plugin_object(unsigned int handle
)
342 // Make sure we aren't asked to make an object for the same handle twice.
343 if (this->objects_
.size() != handle
)
346 Pluginobj
* obj
= make_sized_plugin_object(this->input_file_
,
347 this->plugin_input_file_
.offset
);
348 this->objects_
.push_back(obj
);
352 // Add a new input file.
355 Plugin_manager::add_input_file(char *pathname
)
357 Input_file_argument
file(pathname
, false, "", false, this->options_
);
358 Input_argument
* input_argument
= new Input_argument(file
);
359 Task_token
* next_blocker
= new Task_token(true);
360 next_blocker
->add_blocker();
361 this->workqueue_
->queue_soon(new Read_symbols(this->options_
,
362 this->input_objects_
,
371 this->this_blocker_
= next_blocker
;
377 Pluginobj::Pluginobj(const std::string
& name
, Input_file
* input_file
,
379 : Object(name
, input_file
, false, offset
),
380 nsyms_(0), syms_(NULL
), symbols_(), comdat_map_()
384 // Get symbol resolution info.
387 Pluginobj::get_symbol_resolution_info(int nsyms
, ld_plugin_symbol
* syms
) const
389 if (this->nsyms_
== 0)
391 for (int i
= 0; i
< nsyms
; i
++)
393 ld_plugin_symbol
* isym
= &syms
[i
];
394 Symbol
* lsym
= this->symbols_
[i
];
395 ld_plugin_symbol_resolution res
= LDPR_UNKNOWN
;
397 if (lsym
->is_undefined())
398 // The symbol remains undefined.
400 else if (isym
->def
== LDPK_UNDEF
401 || isym
->def
== LDPK_WEAKUNDEF
402 || isym
->def
== LDPK_COMMON
)
404 // The original symbol was undefined or common.
405 if (lsym
->source() != Symbol::FROM_OBJECT
)
406 res
= LDPR_RESOLVED_EXEC
;
407 else if (lsym
->object()->pluginobj() != NULL
)
408 res
= LDPR_RESOLVED_IR
;
409 else if (lsym
->object()->is_dynamic())
410 res
= LDPR_RESOLVED_DYN
;
412 res
= LDPR_RESOLVED_EXEC
;
416 // The original symbol was a definition.
417 if (lsym
->source() != Symbol::FROM_OBJECT
)
418 res
= LDPR_PREEMPTED_REG
;
419 else if (lsym
->object() == static_cast<const Object
*>(this))
420 res
= (lsym
->in_real_elf()
421 ? LDPR_PREVAILING_DEF
422 : LDPR_PREVAILING_DEF_IRONLY
);
424 res
= (lsym
->object()->pluginobj() != NULL
426 : LDPR_PREEMPTED_REG
);
428 isym
->resolution
= res
;
433 // Return TRUE if the comdat group with key COMDAT_KEY from this object
437 Pluginobj::include_comdat_group(std::string comdat_key
, Layout
* layout
)
439 std::pair
<Comdat_map::iterator
, bool> ins
=
440 this->comdat_map_
.insert(std::make_pair(comdat_key
, false));
442 // If this is the first time we've seen this comdat key, ask the
443 // layout object whether it should be included.
445 ins
.first
->second
= layout
->add_comdat(NULL
, 1, comdat_key
, true);
447 return ins
.first
->second
;
450 // Class Sized_pluginobj.
452 template<int size
, bool big_endian
>
453 Sized_pluginobj
<size
, big_endian
>::Sized_pluginobj(
454 const std::string
& name
,
455 Input_file
* input_file
,
457 : Pluginobj(name
, input_file
, offset
)
461 // Read the symbols. Not used for plugin objects.
463 template<int size
, bool big_endian
>
465 Sized_pluginobj
<size
, big_endian
>::do_read_symbols(Read_symbols_data
*)
470 // Lay out the input sections. Not used for plugin objects.
472 template<int size
, bool big_endian
>
474 Sized_pluginobj
<size
, big_endian
>::do_layout(Symbol_table
*, Layout
*,
480 // Add the symbols to the symbol table.
482 template<int size
, bool big_endian
>
484 Sized_pluginobj
<size
, big_endian
>::do_add_symbols(Symbol_table
*,
490 template<int size
, bool big_endian
>
492 Sized_pluginobj
<size
, big_endian
>::do_add_symbols(Symbol_table
* symtab
,
495 const int sym_size
= elfcpp::Elf_sizes
<size
>::sym_size
;
496 unsigned char symbuf
[sym_size
];
497 elfcpp::Sym
<size
, big_endian
> sym(symbuf
);
498 elfcpp::Sym_write
<size
, big_endian
> osym(symbuf
);
500 typedef typename
elfcpp::Elf_types
<size
>::Elf_WXword Elf_size_type
;
502 this->symbols_
.resize(this->nsyms_
);
504 for (int i
= 0; i
< this->nsyms_
; ++i
)
506 const struct ld_plugin_symbol
*isym
= &this->syms_
[i
];
507 const char* name
= isym
->name
;
508 const char* ver
= isym
->version
;
509 elfcpp::Elf_Half shndx
;
513 if (name
!= NULL
&& name
[0] == '\0')
515 if (ver
!= NULL
&& ver
[0] == '\0')
522 bind
= elfcpp::STB_WEAK
;
528 bind
= elfcpp::STB_GLOBAL
;
536 shndx
= elfcpp::SHN_ABS
;
539 shndx
= elfcpp::SHN_COMMON
;
544 shndx
= elfcpp::SHN_UNDEF
;
548 switch (isym
->visibility
)
551 vis
= elfcpp::STV_DEFAULT
;
554 vis
= elfcpp::STV_DEFAULT
;
557 vis
= elfcpp::STV_DEFAULT
;
561 vis
= elfcpp::STV_DEFAULT
;
565 if (isym
->comdat_key
!= NULL
566 && isym
->comdat_key
[0] != '\0'
567 && !this->include_comdat_group(isym
->comdat_key
, layout
))
568 shndx
= elfcpp::SHN_UNDEF
;
571 osym
.put_st_value(0);
572 osym
.put_st_size(static_cast<Elf_size_type
>(isym
->size
));
573 osym
.put_st_info(bind
, elfcpp::STT_NOTYPE
);
574 osym
.put_st_other(vis
, 0);
575 osym
.put_st_shndx(shndx
);
578 symtab
->add_from_pluginobj
<size
, big_endian
>(this, name
, ver
, &sym
);
582 // Get the size of a section. Not used for plugin objects.
584 template<int size
, bool big_endian
>
586 Sized_pluginobj
<size
, big_endian
>::do_section_size(unsigned int)
592 // Get the name of a section. Not used for plugin objects.
594 template<int size
, bool big_endian
>
596 Sized_pluginobj
<size
, big_endian
>::do_section_name(unsigned int)
599 return std::string();
602 // Return a view of the contents of a section. Not used for plugin objects.
604 template<int size
, bool big_endian
>
606 Sized_pluginobj
<size
, big_endian
>::do_section_contents(unsigned int)
614 // Return section flags. Not used for plugin objects.
616 template<int size
, bool big_endian
>
618 Sized_pluginobj
<size
, big_endian
>::do_section_flags(unsigned int)
624 // Return section address. Not used for plugin objects.
626 template<int size
, bool big_endian
>
628 Sized_pluginobj
<size
, big_endian
>::do_section_address(unsigned int)
634 // Return section type. Not used for plugin objects.
636 template<int size
, bool big_endian
>
638 Sized_pluginobj
<size
, big_endian
>::do_section_type(unsigned int)
644 // Return the section link field. Not used for plugin objects.
646 template<int size
, bool big_endian
>
648 Sized_pluginobj
<size
, big_endian
>::do_section_link(unsigned int)
654 // Return the section link field. Not used for plugin objects.
656 template<int size
, bool big_endian
>
658 Sized_pluginobj
<size
, big_endian
>::do_section_info(unsigned int)
664 // Return the section alignment. Not used for plugin objects.
666 template<int size
, bool big_endian
>
668 Sized_pluginobj
<size
, big_endian
>::do_section_addralign(unsigned int)
674 // Return the Xindex structure to use. Not used for plugin objects.
676 template<int size
, bool big_endian
>
678 Sized_pluginobj
<size
, big_endian
>::do_initialize_xindex()
684 // Get symbol counts. Not used for plugin objects.
686 template<int size
, bool big_endian
>
688 Sized_pluginobj
<size
, big_endian
>::do_get_global_symbol_counts(const Symbol_table
*,
689 size_t*, size_t*) const
694 // Class Add_plugin_symbols.
696 Add_plugin_symbols::~Add_plugin_symbols()
698 if (this->this_blocker_
!= NULL
)
699 delete this->this_blocker_
;
700 // next_blocker_ is deleted by the task associated with the next
704 // We are blocked by this_blocker_. We block next_blocker_. We also
708 Add_plugin_symbols::is_runnable()
710 if (this->this_blocker_
!= NULL
&& this->this_blocker_
->is_blocked())
711 return this->this_blocker_
;
712 if (this->obj_
->is_locked())
713 return this->obj_
->token();
718 Add_plugin_symbols::locks(Task_locker
* tl
)
720 tl
->add(this, this->next_blocker_
);
721 tl
->add(this, this->obj_
->token());
724 // Add the symbols in the object to the symbol table.
727 Add_plugin_symbols::run(Workqueue
*)
729 this->obj_
->add_symbols(this->symtab_
, this->layout_
);
732 // Class Plugin_cleanup. This task calls the plugin cleanup hooks once all
733 // replacement files have been added.
735 class Plugin_cleanup
: public Task
738 Plugin_cleanup(Task_token
* this_blocker
, Task_token
* next_blocker
)
739 : this_blocker_(this_blocker
), next_blocker_(next_blocker
)
744 if (this->this_blocker_
!= NULL
)
745 delete this->this_blocker_
;
751 if (this->this_blocker_
!= NULL
&& this->this_blocker_
->is_blocked())
752 return this->this_blocker_
;
757 locks(Task_locker
* tl
)
758 { tl
->add(this, this->next_blocker_
); }
762 { parameters
->options().plugins()->cleanup(); }
766 { return "Plugin_cleanup"; }
769 Task_token
* this_blocker_
;
770 Task_token
* next_blocker_
;
773 // Class Plugin_hook.
775 Plugin_hook::~Plugin_hook()
779 // Return whether a Plugin_hook task is runnable.
782 Plugin_hook::is_runnable()
784 if (this->this_blocker_
!= NULL
&& this->this_blocker_
->is_blocked())
785 return this->this_blocker_
;
789 // Return a Task_locker for a Plugin_hook task. We don't need any
793 Plugin_hook::locks(Task_locker
*)
797 // Run a Plugin_hook task.
800 Plugin_hook::run(Workqueue
* workqueue
)
802 this->do_plugin_hook(workqueue
);
805 // Run the "all symbols read" plugin hook.
808 Plugin_hook::do_plugin_hook(Workqueue
* workqueue
)
810 gold_assert(this->options_
.has_plugins());
811 this->options_
.plugins()->all_symbols_read(workqueue
,
812 this->input_objects_
,
817 &this->this_blocker_
);
818 workqueue
->queue_soon(new Plugin_cleanup(this->this_blocker_
,
819 this->next_blocker_
));
822 // The C interface routines called by the plugins.
824 #ifdef ENABLE_PLUGINS
826 // Register a claim-file handler.
828 static enum ld_plugin_status
829 register_claim_file(ld_plugin_claim_file_handler handler
)
831 gold_assert(parameters
->options().has_plugins());
832 parameters
->options().plugins()->set_claim_file_handler(handler
);
836 // Register an all-symbols-read handler.
838 static enum ld_plugin_status
839 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler
)
841 gold_assert(parameters
->options().has_plugins());
842 parameters
->options().plugins()->set_all_symbols_read_handler(handler
);
846 // Register a cleanup handler.
848 static enum ld_plugin_status
849 register_cleanup(ld_plugin_cleanup_handler handler
)
851 gold_assert(parameters
->options().has_plugins());
852 parameters
->options().plugins()->set_cleanup_handler(handler
);
856 // Add symbols from a plugin-claimed input file.
858 static enum ld_plugin_status
859 add_symbols(void* handle
, int nsyms
, const ld_plugin_symbol
*syms
)
861 gold_assert(parameters
->options().has_plugins());
862 Pluginobj
* obj
= parameters
->options().plugins()->make_plugin_object(
863 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle
)));
866 obj
->store_incoming_symbols(nsyms
, syms
);
870 // Get the symbol resolution info for a plugin-claimed input file.
872 static enum ld_plugin_status
873 get_symbols(const void * handle
, int nsyms
, ld_plugin_symbol
* syms
)
875 gold_assert(parameters
->options().has_plugins());
876 Pluginobj
* obj
= parameters
->options().plugins()->object(
877 static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle
)));
880 return obj
->get_symbol_resolution_info(nsyms
, syms
);
883 // Add a new (real) input file generated by a plugin.
885 static enum ld_plugin_status
886 add_input_file(char *pathname
)
888 gold_assert(parameters
->options().has_plugins());
889 return parameters
->options().plugins()->add_input_file(pathname
);
892 // Issue a diagnostic message from a plugin.
894 static enum ld_plugin_status
895 message(int level
, char * format
, ...)
898 va_start(args
, format
);
903 parameters
->errors()->info(format
, args
);
906 parameters
->errors()->warning(format
, args
);
910 parameters
->errors()->error(format
, args
);
913 parameters
->errors()->fatal(format
, args
);
921 #endif // ENABLE_PLUGINS
923 // Allocate a Pluginobj object of the appropriate size and endianness.
926 make_sized_plugin_object(Input_file
* input_file
, off_t offset
)
929 Pluginobj
* obj
= NULL
;
931 if (parameters
->target_valid())
932 target
= const_cast<Target
*>(¶meters
->target());
934 target
= const_cast<Target
*>(¶meters
->default_target());
936 if (target
->get_size() == 32)
938 if (target
->is_big_endian())
939 #ifdef HAVE_TARGET_32_BIG
940 obj
= new Sized_pluginobj
<32, true>(input_file
->filename(),
943 gold_error(_("%s: not configured to support "
944 "32-bit big-endian object"),
945 input_file
->filename().c_str());
948 #ifdef HAVE_TARGET_32_LITTLE
949 obj
= new Sized_pluginobj
<32, false>(input_file
->filename(),
952 gold_error(_("%s: not configured to support "
953 "32-bit little-endian object"),
954 input_file
->filename().c_str());
957 else if (target
->get_size() == 64)
959 if (target
->is_big_endian())
960 #ifdef HAVE_TARGET_64_BIG
961 obj
= new Sized_pluginobj
<64, true>(input_file
->filename(),
964 gold_error(_("%s: not configured to support "
965 "64-bit big-endian object"),
966 input_file
->filename().c_str());
969 #ifdef HAVE_TARGET_64_LITTLE
970 obj
= new Sized_pluginobj
<64, false>(input_file
->filename(),
973 gold_error(_("%s: not configured to support "
974 "64-bit little-endian object"),
975 input_file
->filename().c_str());
979 gold_assert(obj
!= NULL
);
980 obj
->set_target(target
);
984 } // End namespace gold.