* archive.cc: Formatting fixes: Remove whitespace between
[external/binutils.git] / gold / plugin.cc
1 // plugin.cc -- plugin manager for gold      -*- C++ -*-
2
3 // Copyright 2008, 2009, 2010 Free Software Foundation, Inc.
4 // Written by Cary Coutant <ccoutant@google.com>.
5
6 // This file is part of gold.
7
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.
12
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.
17
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.
22
23 #include "gold.h"
24
25 #include <cstdio>
26 #include <cstdarg>
27 #include <cstring>
28 #include <string>
29 #include <vector>
30
31 #ifdef ENABLE_PLUGINS
32 #include <dlfcn.h>
33 #endif
34
35 #include "parameters.h"
36 #include "errors.h"
37 #include "fileread.h"
38 #include "layout.h"
39 #include "options.h"
40 #include "plugin.h"
41 #include "target.h"
42 #include "readsyms.h"
43 #include "symtab.h"
44 #include "elfcpp.h"
45
46 namespace gold
47 {
48
49 #ifdef ENABLE_PLUGINS
50
51 // The linker's exported interfaces.
52
53 extern "C"
54 {
55
56 static enum ld_plugin_status
57 register_claim_file(ld_plugin_claim_file_handler handler);
58
59 static enum ld_plugin_status
60 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler);
61
62 static enum ld_plugin_status
63 register_cleanup(ld_plugin_cleanup_handler handler);
64
65 static enum ld_plugin_status
66 add_symbols(void *handle, int nsyms, const struct ld_plugin_symbol *syms);
67
68 static enum ld_plugin_status
69 get_input_file(const void *handle, struct ld_plugin_input_file *file);
70
71 static enum ld_plugin_status
72 release_input_file(const void *handle);
73
74 static enum ld_plugin_status
75 get_symbols(const void *handle, int nsyms, struct ld_plugin_symbol *syms);
76
77 static enum ld_plugin_status
78 add_input_file(const char *pathname);
79
80 static enum ld_plugin_status
81 add_input_library(const char *pathname);
82
83 static enum ld_plugin_status
84 set_extra_library_path(const char *path);
85
86 static enum ld_plugin_status
87 message(int level, const char *format, ...);
88
89 };
90
91 #endif // ENABLE_PLUGINS
92
93 static Pluginobj* make_sized_plugin_object(Input_file* input_file,
94                                            off_t offset, off_t filesize);
95
96 // Plugin methods.
97
98 // Load one plugin library.
99
100 void
101 Plugin::load()
102 {
103 #ifdef ENABLE_PLUGINS
104   // Load the plugin library.
105   // FIXME: Look for the library in standard locations.
106   this->handle_ = dlopen(this->filename_.c_str(), RTLD_NOW);
107   if (this->handle_ == NULL)
108     {
109       gold_error(_("%s: could not load plugin library: %s"),
110                  this->filename_.c_str(), dlerror());
111       return;
112     }
113
114   // Find the plugin's onload entry point.
115   void* ptr = dlsym(this->handle_, "onload");
116   if (ptr == NULL)
117     {
118       gold_error(_("%s: could not find onload entry point"),
119                  this->filename_.c_str());
120       return;
121     }
122   ld_plugin_onload onload;
123   gold_assert(sizeof(onload) == sizeof(ptr));
124   memcpy(&onload, &ptr, sizeof(ptr));
125
126   // Get the linker's version number.
127   const char* ver = get_version_string();
128   int major = 0;
129   int minor = 0;
130   sscanf(ver, "%d.%d", &major, &minor);
131
132   // Allocate and populate a transfer vector.
133   const int tv_fixed_size = 16;
134   int tv_size = this->args_.size() + tv_fixed_size;
135   ld_plugin_tv* tv = new ld_plugin_tv[tv_size];
136
137   // Put LDPT_MESSAGE at the front of the list so the plugin can use it
138   // while processing subsequent entries.
139   int i = 0;
140   tv[i].tv_tag = LDPT_MESSAGE;
141   tv[i].tv_u.tv_message = message;
142
143   ++i;
144   tv[i].tv_tag = LDPT_API_VERSION;
145   tv[i].tv_u.tv_val = LD_PLUGIN_API_VERSION;
146
147   ++i;
148   tv[i].tv_tag = LDPT_GOLD_VERSION;
149   tv[i].tv_u.tv_val = major * 100 + minor;
150
151   ++i;
152   tv[i].tv_tag = LDPT_LINKER_OUTPUT;
153   if (parameters->options().relocatable())
154     tv[i].tv_u.tv_val = LDPO_REL;
155   else if (parameters->options().shared())
156     tv[i].tv_u.tv_val = LDPO_DYN;
157   else
158     tv[i].tv_u.tv_val = LDPO_EXEC;
159
160   ++i;
161   tv[i].tv_tag = LDPT_OUTPUT_NAME;
162   tv[i].tv_u.tv_string = parameters->options().output();
163
164   for (unsigned int j = 0; j < this->args_.size(); ++j)
165     {
166       ++i;
167       tv[i].tv_tag = LDPT_OPTION;
168       tv[i].tv_u.tv_string = this->args_[j].c_str();
169     }
170
171   ++i;
172   tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK;
173   tv[i].tv_u.tv_register_claim_file = register_claim_file;
174
175   ++i;
176   tv[i].tv_tag = LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK;
177   tv[i].tv_u.tv_register_all_symbols_read = register_all_symbols_read;
178
179   ++i;
180   tv[i].tv_tag = LDPT_REGISTER_CLEANUP_HOOK;
181   tv[i].tv_u.tv_register_cleanup = register_cleanup;
182
183   ++i;
184   tv[i].tv_tag = LDPT_ADD_SYMBOLS;
185   tv[i].tv_u.tv_add_symbols = add_symbols;
186
187   ++i;
188   tv[i].tv_tag = LDPT_GET_INPUT_FILE;
189   tv[i].tv_u.tv_get_input_file = get_input_file;
190
191   ++i;
192   tv[i].tv_tag = LDPT_RELEASE_INPUT_FILE;
193   tv[i].tv_u.tv_release_input_file = release_input_file;
194
195   ++i;
196   tv[i].tv_tag = LDPT_GET_SYMBOLS;
197   tv[i].tv_u.tv_get_symbols = get_symbols;
198
199   ++i;
200   tv[i].tv_tag = LDPT_ADD_INPUT_FILE;
201   tv[i].tv_u.tv_add_input_file = add_input_file;
202
203   ++i;
204   tv[i].tv_tag = LDPT_ADD_INPUT_LIBRARY;
205   tv[i].tv_u.tv_add_input_library = add_input_library;
206
207   ++i;
208   tv[i].tv_tag = LDPT_SET_EXTRA_LIBRARY_PATH;
209   tv[i].tv_u.tv_set_extra_library_path = set_extra_library_path;
210
211   ++i;
212   tv[i].tv_tag = LDPT_NULL;
213   tv[i].tv_u.tv_val = 0;
214
215   gold_assert(i == tv_size - 1);
216
217   // Call the onload entry point.
218   (*onload)(tv);
219
220   delete[] tv;
221 #endif // ENABLE_PLUGINS
222 }
223
224 // Call the plugin claim-file handler.
225
226 inline bool
227 Plugin::claim_file(struct ld_plugin_input_file* plugin_input_file)
228 {
229   int claimed = 0;
230
231   if (this->claim_file_handler_ != NULL)
232     {
233       (*this->claim_file_handler_)(plugin_input_file, &claimed);
234       if (claimed)
235         return true;
236     }
237   return false;
238 }
239
240 // Call the all-symbols-read handler.
241
242 inline void
243 Plugin::all_symbols_read()
244 {
245   if (this->all_symbols_read_handler_ != NULL)
246     (*this->all_symbols_read_handler_)();
247 }
248
249 // Call the cleanup handler.
250
251 inline void
252 Plugin::cleanup()
253 {
254   if (this->cleanup_handler_ != NULL && !this->cleanup_done_)
255     {
256       // Set this flag before calling to prevent a recursive plunge
257       // in the event that a plugin's cleanup handler issues a
258       // fatal error.
259       this->cleanup_done_ = true;
260       (*this->cleanup_handler_)();
261     }
262 }
263
264 // Plugin_manager methods.
265
266 Plugin_manager::~Plugin_manager()
267 {
268   for (Plugin_list::iterator p = this->plugins_.begin();
269        p != this->plugins_.end();
270        ++p)
271     delete *p;
272   this->plugins_.clear();
273   for (Object_list::iterator obj = this->objects_.begin();
274        obj != this->objects_.end();
275        ++obj)
276     delete *obj;
277   this->objects_.clear();
278 }
279
280 // Load all plugin libraries.
281
282 void
283 Plugin_manager::load_plugins()
284 {
285   for (this->current_ = this->plugins_.begin();
286        this->current_ != this->plugins_.end();
287        ++this->current_)
288     (*this->current_)->load();
289 }
290
291 // Call the plugin claim-file handlers in turn to see if any claim the file.
292
293 Pluginobj*
294 Plugin_manager::claim_file(Input_file* input_file, off_t offset,
295                            off_t filesize)
296 {
297   if (this->in_replacement_phase_)
298     return NULL;
299
300   unsigned int handle = this->objects_.size();
301   this->input_file_ = input_file;
302   this->plugin_input_file_.name = input_file->filename().c_str();
303   this->plugin_input_file_.fd = input_file->file().descriptor();
304   this->plugin_input_file_.offset = offset;
305   this->plugin_input_file_.filesize = filesize;
306   this->plugin_input_file_.handle = reinterpret_cast<void*>(handle);
307
308   for (this->current_ = this->plugins_.begin();
309        this->current_ != this->plugins_.end();
310        ++this->current_)
311     {
312       if ((*this->current_)->claim_file(&this->plugin_input_file_))
313         {
314           if (this->objects_.size() > handle)
315             return this->objects_[handle];
316
317           // If the plugin claimed the file but did not call the
318           // add_symbols callback, we need to create the Pluginobj now.
319           Pluginobj* obj = this->make_plugin_object(handle);
320           return obj;
321         }
322     }
323
324   return NULL;
325 }
326
327 // Call the all-symbols-read handlers.
328
329 void
330 Plugin_manager::all_symbols_read(Workqueue* workqueue, Task* task,
331                                  Input_objects* input_objects,
332                                  Symbol_table* symtab, Layout* layout,
333                                  Dirsearch* dirpath, Mapfile* mapfile,
334                                  Task_token** last_blocker)
335 {
336   this->in_replacement_phase_ = true;
337   this->workqueue_ = workqueue;
338   this->task_ = task;
339   this->input_objects_ = input_objects;
340   this->symtab_ = symtab;
341   this->layout_ = layout;
342   this->dirpath_ = dirpath;
343   this->mapfile_ = mapfile;
344   this->this_blocker_ = NULL;
345
346   for (this->current_ = this->plugins_.begin();
347        this->current_ != this->plugins_.end();
348        ++this->current_)
349     (*this->current_)->all_symbols_read();
350
351   *last_blocker = this->this_blocker_;
352 }
353
354 // Layout deferred objects.
355
356 void
357 Plugin_manager::layout_deferred_objects()
358 {
359   Deferred_layout_list::iterator obj;
360
361   for (obj = this->deferred_layout_objects_.begin();
362        obj != this->deferred_layout_objects_.end();
363        ++obj)
364     (*obj)->layout_deferred_sections(this->layout_);
365 }
366
367 // Call the cleanup handlers.
368
369 void
370 Plugin_manager::cleanup()
371 {
372   for (this->current_ = this->plugins_.begin();
373        this->current_ != this->plugins_.end();
374        ++this->current_)
375     (*this->current_)->cleanup();
376 }
377
378 // Make a new Pluginobj object.  This is called when the plugin calls
379 // the add_symbols API.
380
381 Pluginobj*
382 Plugin_manager::make_plugin_object(unsigned int handle)
383 {
384   // Make sure we aren't asked to make an object for the same handle twice.
385   if (this->objects_.size() != handle)
386     return NULL;
387
388   Pluginobj* obj = make_sized_plugin_object(this->input_file_,
389                                             this->plugin_input_file_.offset,
390                                             this->plugin_input_file_.filesize);
391   this->objects_.push_back(obj);
392   return obj;
393 }
394
395 // Get the input file information with an open (possibly re-opened)
396 // file descriptor.
397
398 ld_plugin_status
399 Plugin_manager::get_input_file(unsigned int handle,
400                                struct ld_plugin_input_file* file)
401 {
402   Pluginobj* obj = this->object(handle);
403   if (obj == NULL)
404     return LDPS_BAD_HANDLE;
405
406   obj->lock(this->task_);
407   file->name = obj->filename().c_str();
408   file->fd = obj->descriptor();
409   file->offset = obj->offset();
410   file->filesize = obj->filesize();
411   file->handle = reinterpret_cast<void*>(handle);
412   return LDPS_OK;
413 }
414
415 // Release the input file.
416
417 ld_plugin_status
418 Plugin_manager::release_input_file(unsigned int handle)
419 {
420   Pluginobj* obj = this->object(handle);
421   if (obj == NULL)
422     return LDPS_BAD_HANDLE;
423
424   obj->unlock(this->task_);
425   return LDPS_OK;
426 }
427
428 // Add a new library path.
429
430 ld_plugin_status
431 Plugin_manager::set_extra_library_path(const char* path)
432 {
433   this->extra_search_path_ = std::string(path);
434   return LDPS_OK;
435 }
436
437 // Add a new input file.
438
439 ld_plugin_status
440 Plugin_manager::add_input_file(const char* pathname, bool is_lib)
441 {
442   Input_file_argument file(pathname,
443                            (is_lib
444                             ? Input_file_argument::INPUT_FILE_TYPE_LIBRARY
445                             : Input_file_argument::INPUT_FILE_TYPE_FILE),
446                            (is_lib
447                             ? this->extra_search_path_.c_str()
448                             : ""),
449                            false,
450                            this->options_);
451   Input_argument* input_argument = new Input_argument(file);
452   Task_token* next_blocker = new Task_token(true);
453   next_blocker->add_blocker();
454   if (parameters->options().incremental())
455     gold_error(_("input files added by plug-ins in --incremental mode not "
456                  "supported yet"));
457   this->workqueue_->queue_soon(new Read_symbols(this->input_objects_,
458                                                 this->symtab_,
459                                                 this->layout_,
460                                                 this->dirpath_,
461                                                 0,
462                                                 this->mapfile_,
463                                                 input_argument,
464                                                 NULL,
465                                                 NULL,
466                                                 this->this_blocker_,
467                                                 next_blocker));
468   this->this_blocker_ = next_blocker;
469   return LDPS_OK;
470 }
471
472 // Class Pluginobj.
473
474 Pluginobj::Pluginobj(const std::string& name, Input_file* input_file,
475                      off_t offset, off_t filesize)
476   : Object(name, input_file, false, offset),
477     nsyms_(0), syms_(NULL), symbols_(), filesize_(filesize), comdat_map_()
478 {
479 }
480
481 // Return TRUE if a defined symbol might be reachable from outside the
482 // universe of claimed objects.
483
484 static inline bool
485 is_visible_from_outside(Symbol* lsym)
486 {
487   if (lsym->in_real_elf())
488     return true;
489   if (parameters->options().relocatable())
490     return true;
491   if (parameters->options().export_dynamic() || parameters->options().shared())
492     return lsym->is_externally_visible();
493   return false;
494 }
495
496 // Get symbol resolution info.
497
498 ld_plugin_status
499 Pluginobj::get_symbol_resolution_info(int nsyms, ld_plugin_symbol* syms) const
500 {
501   if (nsyms > this->nsyms_)
502     return LDPS_NO_SYMS;
503
504   if (static_cast<size_t>(nsyms) > this->symbols_.size())
505     {
506       // We never decided to include this object. We mark all symbols as
507       // preempted.
508       gold_assert(this->symbols_.size() == 0);
509       for (int i = 0; i < nsyms; i++)
510         syms[i].resolution = LDPR_PREEMPTED_REG;
511       return LDPS_OK;
512     }
513
514   for (int i = 0; i < nsyms; i++)
515     {
516       ld_plugin_symbol* isym = &syms[i];
517       Symbol* lsym = this->symbols_[i];
518       ld_plugin_symbol_resolution res = LDPR_UNKNOWN;
519
520       if (lsym->is_undefined())
521         // The symbol remains undefined.
522         res = LDPR_UNDEF;
523       else if (isym->def == LDPK_UNDEF
524                || isym->def == LDPK_WEAKUNDEF
525                || isym->def == LDPK_COMMON)
526         {
527           // The original symbol was undefined or common.
528           if (lsym->source() != Symbol::FROM_OBJECT)
529             res = LDPR_RESOLVED_EXEC;
530           else if (lsym->object()->pluginobj() == this)
531             res = (is_visible_from_outside(lsym)
532                    ? LDPR_PREVAILING_DEF
533                    : LDPR_PREVAILING_DEF_IRONLY);
534           else if (lsym->object()->pluginobj() != NULL)
535             res = LDPR_RESOLVED_IR;
536           else if (lsym->object()->is_dynamic())
537             res = LDPR_RESOLVED_DYN;
538           else
539             res = LDPR_RESOLVED_EXEC;
540         }
541       else
542         {
543           // The original symbol was a definition.
544           if (lsym->source() != Symbol::FROM_OBJECT)
545             res = LDPR_PREEMPTED_REG;
546           else if (lsym->object() == static_cast<const Object*>(this))
547             res = (is_visible_from_outside(lsym)
548                    ? LDPR_PREVAILING_DEF
549                    : LDPR_PREVAILING_DEF_IRONLY);
550           else
551             res = (lsym->object()->pluginobj() != NULL
552                    ? LDPR_PREEMPTED_IR
553                    : LDPR_PREEMPTED_REG);
554         }
555       isym->resolution = res;
556     }
557   return LDPS_OK;
558 }
559
560 // Return TRUE if the comdat group with key COMDAT_KEY from this object
561 // should be kept.
562
563 bool
564 Pluginobj::include_comdat_group(std::string comdat_key, Layout* layout)
565 {
566   std::pair<Comdat_map::iterator, bool> ins =
567     this->comdat_map_.insert(std::make_pair(comdat_key, false));
568
569   // If this is the first time we've seen this comdat key, ask the
570   // layout object whether it should be included.
571   if (ins.second)
572     ins.first->second = layout->find_or_add_kept_section(comdat_key,
573                                                          NULL, 0, true,
574                                                          true, NULL);
575
576   return ins.first->second;
577 }
578
579 // Class Sized_pluginobj.
580
581 template<int size, bool big_endian>
582 Sized_pluginobj<size, big_endian>::Sized_pluginobj(
583     const std::string& name,
584     Input_file* input_file,
585     off_t offset,
586     off_t filesize)
587   : Pluginobj(name, input_file, offset, filesize)
588 {
589 }
590
591 // Read the symbols.  Not used for plugin objects.
592
593 template<int size, bool big_endian>
594 void
595 Sized_pluginobj<size, big_endian>::do_read_symbols(Read_symbols_data*)
596 {
597   gold_unreachable();
598 }
599
600 // Lay out the input sections.  Not used for plugin objects.
601
602 template<int size, bool big_endian>
603 void
604 Sized_pluginobj<size, big_endian>::do_layout(Symbol_table*, Layout*,
605                                              Read_symbols_data*)
606 {
607   gold_unreachable();
608 }
609
610 // Add the symbols to the symbol table.
611
612 template<int size, bool big_endian>
613 void
614 Sized_pluginobj<size, big_endian>::do_add_symbols(Symbol_table* symtab,
615                                                   Read_symbols_data*,
616                                                   Layout* layout)
617 {
618   const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
619   unsigned char symbuf[sym_size];
620   elfcpp::Sym<size, big_endian> sym(symbuf);
621   elfcpp::Sym_write<size, big_endian> osym(symbuf);
622
623   typedef typename elfcpp::Elf_types<size>::Elf_WXword Elf_size_type;
624
625   this->symbols_.resize(this->nsyms_);
626
627   for (int i = 0; i < this->nsyms_; ++i)
628     {
629       const struct ld_plugin_symbol* isym = &this->syms_[i];
630       const char* name = isym->name;
631       const char* ver = isym->version;
632       elfcpp::Elf_Half shndx;
633       elfcpp::STB bind;
634       elfcpp::STV vis;
635
636       if (name != NULL && name[0] == '\0')
637         name = NULL;
638       if (ver != NULL && ver[0] == '\0')
639         ver = NULL;
640
641       switch (isym->def)
642         {
643         case LDPK_WEAKDEF:
644         case LDPK_WEAKUNDEF:
645           bind = elfcpp::STB_WEAK;
646           break;
647         case LDPK_DEF:
648         case LDPK_UNDEF:
649         case LDPK_COMMON:
650         default:
651           bind = elfcpp::STB_GLOBAL;
652           break;
653         }
654
655       switch (isym->def)
656         {
657         case LDPK_DEF:
658         case LDPK_WEAKDEF:
659           shndx = elfcpp::SHN_ABS;
660           break;
661         case LDPK_COMMON:
662           shndx = elfcpp::SHN_COMMON;
663           break;
664         case LDPK_UNDEF:
665         case LDPK_WEAKUNDEF:
666         default:
667           shndx = elfcpp::SHN_UNDEF;
668           break;
669         }
670
671       switch (isym->visibility)
672         {
673         case LDPV_PROTECTED:
674           vis = elfcpp::STV_PROTECTED;
675           break;
676         case LDPV_INTERNAL:
677           vis = elfcpp::STV_INTERNAL;
678           break;
679         case LDPV_HIDDEN:
680           vis = elfcpp::STV_HIDDEN;
681           break;
682         case LDPV_DEFAULT:
683         default:
684           vis = elfcpp::STV_DEFAULT;
685           break;
686         }
687
688       if (isym->comdat_key != NULL
689           && isym->comdat_key[0] != '\0'
690           && !this->include_comdat_group(isym->comdat_key, layout))
691         shndx = elfcpp::SHN_UNDEF;
692
693       osym.put_st_name(0);
694       osym.put_st_value(0);
695       osym.put_st_size(static_cast<Elf_size_type>(isym->size));
696       osym.put_st_info(bind, elfcpp::STT_NOTYPE);
697       osym.put_st_other(vis, 0);
698       osym.put_st_shndx(shndx);
699
700       this->symbols_[i] =
701         symtab->add_from_pluginobj<size, big_endian>(this, name, ver, &sym);
702     }
703 }
704
705 template<int size, bool big_endian>
706 Archive::Should_include
707 Sized_pluginobj<size, big_endian>::do_should_include_member(
708     Symbol_table* symtab,
709     Layout* layout,
710     Read_symbols_data*,
711     std::string* why)
712 {
713   char* tmpbuf = NULL;
714   size_t tmpbuflen = 0;
715
716   for (int i = 0; i < this->nsyms_; ++i)
717     {
718       const struct ld_plugin_symbol& sym = this->syms_[i];
719       const char* name = sym.name;
720       Symbol* symbol;
721       Archive::Should_include t = Archive::should_include_member(symtab,
722                                                                  layout,
723                                                                  name,
724                                                                  &symbol, why,
725                                                                  &tmpbuf,
726                                                                  &tmpbuflen);
727       if (t == Archive::SHOULD_INCLUDE_YES)
728         {
729           if (tmpbuf != NULL)
730             free(tmpbuf);
731           return t;
732         }
733     }
734   if (tmpbuf != NULL)
735     free(tmpbuf);
736   return Archive::SHOULD_INCLUDE_UNKNOWN;
737 }
738
739 // Get the size of a section.  Not used for plugin objects.
740
741 template<int size, bool big_endian>
742 uint64_t
743 Sized_pluginobj<size, big_endian>::do_section_size(unsigned int)
744 {
745   gold_unreachable();
746   return 0;
747 }
748
749 // Get the name of a section.  Not used for plugin objects.
750
751 template<int size, bool big_endian>
752 std::string
753 Sized_pluginobj<size, big_endian>::do_section_name(unsigned int)
754 {
755   gold_unreachable();
756   return std::string();
757 }
758
759 // Return a view of the contents of a section.  Not used for plugin objects.
760
761 template<int size, bool big_endian>
762 Object::Location
763 Sized_pluginobj<size, big_endian>::do_section_contents(unsigned int)
764 {
765   Location loc(0, 0);
766
767   gold_unreachable();
768   return loc;
769 }
770
771 // Return section flags.  Not used for plugin objects.
772
773 template<int size, bool big_endian>
774 uint64_t
775 Sized_pluginobj<size, big_endian>::do_section_flags(unsigned int)
776 {
777   gold_unreachable();
778   return 0;
779 }
780
781 // Return section entsize.  Not used for plugin objects.
782
783 template<int size, bool big_endian>
784 uint64_t
785 Sized_pluginobj<size, big_endian>::do_section_entsize(unsigned int)
786 {
787   gold_unreachable();
788   return 0;
789 }
790
791 // Return section address.  Not used for plugin objects.
792
793 template<int size, bool big_endian>
794 uint64_t
795 Sized_pluginobj<size, big_endian>::do_section_address(unsigned int)
796 {
797   gold_unreachable();
798   return 0;
799 }
800
801 // Return section type.  Not used for plugin objects.
802
803 template<int size, bool big_endian>
804 unsigned int
805 Sized_pluginobj<size, big_endian>::do_section_type(unsigned int)
806 {
807   gold_unreachable();
808   return 0;
809 }
810
811 // Return the section link field.  Not used for plugin objects.
812
813 template<int size, bool big_endian>
814 unsigned int
815 Sized_pluginobj<size, big_endian>::do_section_link(unsigned int)
816 {
817   gold_unreachable();
818   return 0;
819 }
820
821 // Return the section link field.  Not used for plugin objects.
822
823 template<int size, bool big_endian>
824 unsigned int
825 Sized_pluginobj<size, big_endian>::do_section_info(unsigned int)
826 {
827   gold_unreachable();
828   return 0;
829 }
830
831 // Return the section alignment.  Not used for plugin objects.
832
833 template<int size, bool big_endian>
834 uint64_t
835 Sized_pluginobj<size, big_endian>::do_section_addralign(unsigned int)
836 {
837   gold_unreachable();
838   return 0;
839 }
840
841 // Return the Xindex structure to use.  Not used for plugin objects.
842
843 template<int size, bool big_endian>
844 Xindex*
845 Sized_pluginobj<size, big_endian>::do_initialize_xindex()
846 {
847   gold_unreachable();
848   return NULL;
849 }
850
851 // Get symbol counts.  Not used for plugin objects.
852
853 template<int size, bool big_endian>
854 void
855 Sized_pluginobj<size, big_endian>::do_get_global_symbol_counts(const Symbol_table*,
856                                                    size_t*, size_t*) const
857 {
858   gold_unreachable();
859 }
860
861 // Get symbols.  Not used for plugin objects.
862
863 template<int size, bool big_endian>
864 const Object::Symbols*
865 Sized_pluginobj<size, big_endian>::do_get_global_symbols() const
866 {
867   gold_unreachable();
868 }
869
870 // Class Plugin_finish.  This task runs after all replacement files have
871 // been added.  For now, it's a placeholder for a possible plugin API
872 // to allow the plugin to release most of its resources.  The cleanup
873 // handlers must be called later, because they can remove the temporary
874 // object files that are needed until the end of the link.
875
876 class Plugin_finish : public Task
877 {
878  public:
879   Plugin_finish(Task_token* this_blocker, Task_token* next_blocker)
880     : this_blocker_(this_blocker), next_blocker_(next_blocker)
881   { }
882
883   ~Plugin_finish()
884   {
885     if (this->this_blocker_ != NULL)
886       delete this->this_blocker_;
887   }
888
889   Task_token*
890   is_runnable()
891   {
892     if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
893       return this->this_blocker_;
894     return NULL;
895   }
896
897   void
898   locks(Task_locker* tl)
899   { tl->add(this, this->next_blocker_); }
900
901   void
902   run(Workqueue*)
903   {
904     // We could call early cleanup handlers here.
905   }
906
907   std::string
908   get_name() const
909   { return "Plugin_finish"; }
910
911  private:
912   Task_token* this_blocker_;
913   Task_token* next_blocker_;
914 };
915
916 // Class Plugin_hook.
917
918 Plugin_hook::~Plugin_hook()
919 {
920 }
921
922 // Return whether a Plugin_hook task is runnable.
923
924 Task_token*
925 Plugin_hook::is_runnable()
926 {
927   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
928     return this->this_blocker_;
929   return NULL;
930 }
931
932 // Return a Task_locker for a Plugin_hook task.  We don't need any
933 // locks here.
934
935 void
936 Plugin_hook::locks(Task_locker*)
937 {
938 }
939
940 // Run the "all symbols read" plugin hook.
941
942 void
943 Plugin_hook::run(Workqueue* workqueue)
944 {
945   gold_assert(this->options_.has_plugins());
946   Symbol* start_sym;
947   if (parameters->options().entry())
948     start_sym = this->symtab_->lookup(parameters->options().entry());
949   else
950     start_sym = this->symtab_->lookup("_start");
951   if (start_sym != NULL)
952     start_sym->set_in_real_elf();
953
954   this->options_.plugins()->all_symbols_read(workqueue,
955                                              this,
956                                              this->input_objects_,
957                                              this->symtab_,
958                                              this->layout_,
959                                              this->dirpath_,
960                                              this->mapfile_,
961                                              &this->this_blocker_);
962   workqueue->queue_soon(new Plugin_finish(this->this_blocker_,
963                                           this->next_blocker_));
964 }
965
966 // The C interface routines called by the plugins.
967
968 #ifdef ENABLE_PLUGINS
969
970 // Register a claim-file handler.
971
972 static enum ld_plugin_status
973 register_claim_file(ld_plugin_claim_file_handler handler)
974 {
975   gold_assert(parameters->options().has_plugins());
976   parameters->options().plugins()->set_claim_file_handler(handler);
977   return LDPS_OK;
978 }
979
980 // Register an all-symbols-read handler.
981
982 static enum ld_plugin_status
983 register_all_symbols_read(ld_plugin_all_symbols_read_handler handler)
984 {
985   gold_assert(parameters->options().has_plugins());
986   parameters->options().plugins()->set_all_symbols_read_handler(handler);
987   return LDPS_OK;
988 }
989
990 // Register a cleanup handler.
991
992 static enum ld_plugin_status
993 register_cleanup(ld_plugin_cleanup_handler handler)
994 {
995   gold_assert(parameters->options().has_plugins());
996   parameters->options().plugins()->set_cleanup_handler(handler);
997   return LDPS_OK;
998 }
999
1000 // Add symbols from a plugin-claimed input file.
1001
1002 static enum ld_plugin_status
1003 add_symbols(void* handle, int nsyms, const ld_plugin_symbol* syms)
1004 {
1005   gold_assert(parameters->options().has_plugins());
1006   Pluginobj* obj = parameters->options().plugins()->make_plugin_object(
1007       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
1008   if (obj == NULL)
1009     return LDPS_ERR;
1010   obj->store_incoming_symbols(nsyms, syms);
1011   return LDPS_OK;
1012 }
1013
1014 // Get the input file information with an open (possibly re-opened)
1015 // file descriptor.
1016
1017 static enum ld_plugin_status
1018 get_input_file(const void* handle, struct ld_plugin_input_file* file)
1019 {
1020   gold_assert(parameters->options().has_plugins());
1021   unsigned int obj_index =
1022       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
1023   return parameters->options().plugins()->get_input_file(obj_index, file);
1024 }
1025
1026 // Release the input file.
1027
1028 static enum ld_plugin_status
1029 release_input_file(const void* handle)
1030 {
1031   gold_assert(parameters->options().has_plugins());
1032   unsigned int obj_index =
1033       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
1034   return parameters->options().plugins()->release_input_file(obj_index);
1035 }
1036
1037 // Get the symbol resolution info for a plugin-claimed input file.
1038
1039 static enum ld_plugin_status
1040 get_symbols(const void* handle, int nsyms, ld_plugin_symbol* syms)
1041 {
1042   gold_assert(parameters->options().has_plugins());
1043   Pluginobj* obj = parameters->options().plugins()->object(
1044       static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
1045   if (obj == NULL)
1046     return LDPS_ERR;
1047   return obj->get_symbol_resolution_info(nsyms, syms);
1048 }
1049
1050 // Add a new (real) input file generated by a plugin.
1051
1052 static enum ld_plugin_status
1053 add_input_file(const char* pathname)
1054 {
1055   gold_assert(parameters->options().has_plugins());
1056   return parameters->options().plugins()->add_input_file(pathname, false);
1057 }
1058
1059 // Add a new (real) library required by a plugin.
1060
1061 static enum ld_plugin_status
1062 add_input_library(const char* pathname)
1063 {
1064   gold_assert(parameters->options().has_plugins());
1065   return parameters->options().plugins()->add_input_file(pathname, true);
1066 }
1067
1068 // Set the extra library path to be used by libraries added via
1069 // add_input_library
1070
1071 static enum ld_plugin_status
1072 set_extra_library_path(const char* path)
1073 {
1074   gold_assert(parameters->options().has_plugins());
1075   return parameters->options().plugins()->set_extra_library_path(path);
1076 }
1077
1078 // Issue a diagnostic message from a plugin.
1079
1080 static enum ld_plugin_status
1081 message(int level, const char* format, ...)
1082 {
1083   va_list args;
1084   va_start(args, format);
1085
1086   switch (level)
1087     {
1088     case LDPL_INFO:
1089       parameters->errors()->info(format, args);
1090       break;
1091     case LDPL_WARNING:
1092       parameters->errors()->warning(format, args);
1093       break;
1094     case LDPL_ERROR:
1095     default:
1096       parameters->errors()->error(format, args);
1097       break;
1098     case LDPL_FATAL:
1099       parameters->errors()->fatal(format, args);
1100       break;
1101     }
1102
1103   va_end(args);
1104   return LDPS_OK;
1105 }
1106
1107 #endif // ENABLE_PLUGINS
1108
1109 // Allocate a Pluginobj object of the appropriate size and endianness.
1110
1111 static Pluginobj*
1112 make_sized_plugin_object(Input_file* input_file, off_t offset, off_t filesize)
1113 {
1114   Pluginobj* obj = NULL;
1115
1116   parameters_force_valid_target();
1117   const Target& target(parameters->target());
1118
1119   if (target.get_size() == 32)
1120     {
1121       if (target.is_big_endian())
1122 #ifdef HAVE_TARGET_32_BIG
1123         obj = new Sized_pluginobj<32, true>(input_file->filename(),
1124                                             input_file, offset, filesize);
1125 #else
1126         gold_error(_("%s: not configured to support "
1127                      "32-bit big-endian object"),
1128                    input_file->filename().c_str());
1129 #endif
1130       else
1131 #ifdef HAVE_TARGET_32_LITTLE
1132         obj = new Sized_pluginobj<32, false>(input_file->filename(),
1133                                              input_file, offset, filesize);
1134 #else
1135         gold_error(_("%s: not configured to support "
1136                      "32-bit little-endian object"),
1137                    input_file->filename().c_str());
1138 #endif
1139     }
1140   else if (target.get_size() == 64)
1141     {
1142       if (target.is_big_endian())
1143 #ifdef HAVE_TARGET_64_BIG
1144         obj = new Sized_pluginobj<64, true>(input_file->filename(),
1145                                             input_file, offset, filesize);
1146 #else
1147         gold_error(_("%s: not configured to support "
1148                      "64-bit big-endian object"),
1149                    input_file->filename().c_str());
1150 #endif
1151       else
1152 #ifdef HAVE_TARGET_64_LITTLE
1153         obj = new Sized_pluginobj<64, false>(input_file->filename(),
1154                                              input_file, offset, filesize);
1155 #else
1156         gold_error(_("%s: not configured to support "
1157                      "64-bit little-endian object"),
1158                    input_file->filename().c_str());
1159 #endif
1160     }
1161
1162   gold_assert(obj != NULL);
1163   return obj;
1164 }
1165
1166 } // End namespace gold.