| 1 | // plugin.h -- plugin manager for gold -*- C++ -*- |
| 2 | |
| 3 | // Copyright 2008, 2009 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 | #ifndef GOLD_PLUGIN_H |
| 24 | #define GOLD_PLUGIN_H |
| 25 | |
| 26 | #include <list> |
| 27 | #include <string> |
| 28 | |
| 29 | #include "object.h" |
| 30 | #include "plugin-api.h" |
| 31 | #include "workqueue.h" |
| 32 | |
| 33 | namespace gold |
| 34 | { |
| 35 | |
| 36 | class General_options; |
| 37 | class Input_file; |
| 38 | class Input_objects; |
| 39 | class Symbol_table; |
| 40 | class Layout; |
| 41 | class Dirsearch; |
| 42 | class Mapfile; |
| 43 | class Task_token; |
| 44 | class Pluginobj; |
| 45 | |
| 46 | // This class represents a single plugin library. |
| 47 | |
| 48 | class Plugin |
| 49 | { |
| 50 | public: |
| 51 | Plugin(const char* filename) |
| 52 | : handle_(NULL), |
| 53 | filename_(filename), |
| 54 | args_(), |
| 55 | claim_file_handler_(NULL), |
| 56 | all_symbols_read_handler_(NULL), |
| 57 | cleanup_handler_(NULL) |
| 58 | { } |
| 59 | |
| 60 | ~Plugin() |
| 61 | { } |
| 62 | |
| 63 | // Load the library and call its entry point. |
| 64 | void |
| 65 | load(); |
| 66 | |
| 67 | // Call the claim-file handler. |
| 68 | bool |
| 69 | claim_file(struct ld_plugin_input_file *plugin_input_file); |
| 70 | |
| 71 | // Call the all-symbols-read handler. |
| 72 | void |
| 73 | all_symbols_read(); |
| 74 | |
| 75 | // Call the cleanup handler. |
| 76 | void |
| 77 | cleanup(); |
| 78 | |
| 79 | // Register a claim-file handler. |
| 80 | void |
| 81 | set_claim_file_handler(ld_plugin_claim_file_handler handler) |
| 82 | { this->claim_file_handler_ = handler; } |
| 83 | |
| 84 | // Register an all-symbols-read handler. |
| 85 | void |
| 86 | set_all_symbols_read_handler(ld_plugin_all_symbols_read_handler handler) |
| 87 | { this->all_symbols_read_handler_ = handler; } |
| 88 | |
| 89 | // Register a claim-file handler. |
| 90 | void |
| 91 | set_cleanup_handler(ld_plugin_cleanup_handler handler) |
| 92 | { this->cleanup_handler_ = handler; } |
| 93 | |
| 94 | // Add an argument |
| 95 | void |
| 96 | add_option(const char *arg) |
| 97 | { |
| 98 | this->args_.push_back(arg); |
| 99 | } |
| 100 | |
| 101 | private: |
| 102 | Plugin(const Plugin&); |
| 103 | Plugin& operator=(const Plugin&); |
| 104 | |
| 105 | // The shared library handle returned by dlopen. |
| 106 | void* handle_; |
| 107 | // The argument string given to --plugin. |
| 108 | std::string filename_; |
| 109 | // The list of argument string given to --plugin-opt. |
| 110 | std::vector<std::string> args_; |
| 111 | // The plugin's event handlers. |
| 112 | ld_plugin_claim_file_handler claim_file_handler_; |
| 113 | ld_plugin_all_symbols_read_handler all_symbols_read_handler_; |
| 114 | ld_plugin_cleanup_handler cleanup_handler_; |
| 115 | }; |
| 116 | |
| 117 | // A manager class for plugins. |
| 118 | |
| 119 | class Plugin_manager |
| 120 | { |
| 121 | public: |
| 122 | Plugin_manager(const General_options& options) |
| 123 | : plugins_(), objects_(), deferred_layout_objects_(), input_file_(NULL), |
| 124 | plugin_input_file_(), in_replacement_phase_(false), cleanup_done_(false), |
| 125 | options_(options), workqueue_(NULL), task_(NULL), input_objects_(NULL), |
| 126 | symtab_(NULL), layout_(NULL), dirpath_(NULL), mapfile_(NULL), |
| 127 | this_blocker_(NULL) |
| 128 | { this->current_ = plugins_.end(); } |
| 129 | |
| 130 | ~Plugin_manager(); |
| 131 | |
| 132 | // Add a plugin library. |
| 133 | void |
| 134 | add_plugin(const char* filename) |
| 135 | { this->plugins_.push_back(new Plugin(filename)); } |
| 136 | |
| 137 | // Add an argument to the current plugin. |
| 138 | void |
| 139 | add_plugin_option(const char* opt) |
| 140 | { |
| 141 | Plugin* last = this->plugins_.back(); |
| 142 | last->add_option(opt); |
| 143 | } |
| 144 | |
| 145 | // Load all plugin libraries. |
| 146 | void |
| 147 | load_plugins(); |
| 148 | |
| 149 | // Call the plugin claim-file handlers in turn to see if any claim the file. |
| 150 | Pluginobj* |
| 151 | claim_file(Input_file *input_file, off_t offset, off_t filesize); |
| 152 | |
| 153 | // Call the all-symbols-read handlers. |
| 154 | void |
| 155 | all_symbols_read(Workqueue* workqueue, Task* task, |
| 156 | Input_objects* input_objects, Symbol_table* symtab, |
| 157 | Layout* layout, Dirsearch* dirpath, Mapfile* mapfile, |
| 158 | Task_token** last_blocker); |
| 159 | |
| 160 | // Run deferred layout. |
| 161 | void |
| 162 | layout_deferred_objects(); |
| 163 | |
| 164 | // Call the cleanup handlers. |
| 165 | void |
| 166 | cleanup(); |
| 167 | |
| 168 | // Register a claim-file handler. |
| 169 | void |
| 170 | set_claim_file_handler(ld_plugin_claim_file_handler handler) |
| 171 | { |
| 172 | gold_assert(this->current_ != plugins_.end()); |
| 173 | (*this->current_)->set_claim_file_handler(handler); |
| 174 | } |
| 175 | |
| 176 | // Register an all-symbols-read handler. |
| 177 | void |
| 178 | set_all_symbols_read_handler(ld_plugin_all_symbols_read_handler handler) |
| 179 | { |
| 180 | gold_assert(this->current_ != plugins_.end()); |
| 181 | (*this->current_)->set_all_symbols_read_handler(handler); |
| 182 | } |
| 183 | |
| 184 | // Register a claim-file handler. |
| 185 | void |
| 186 | set_cleanup_handler(ld_plugin_cleanup_handler handler) |
| 187 | { |
| 188 | gold_assert(this->current_ != plugins_.end()); |
| 189 | (*this->current_)->set_cleanup_handler(handler); |
| 190 | } |
| 191 | |
| 192 | // Make a new Pluginobj object. This is called when the plugin calls |
| 193 | // the add_symbols API. |
| 194 | Pluginobj* |
| 195 | make_plugin_object(unsigned int handle); |
| 196 | |
| 197 | // Return the Pluginobj associated with the given HANDLE. |
| 198 | Pluginobj* |
| 199 | object(unsigned int handle) const |
| 200 | { |
| 201 | if (handle >= this->objects_.size()) |
| 202 | return NULL; |
| 203 | return this->objects_[handle]; |
| 204 | } |
| 205 | |
| 206 | // Return TRUE if any input files have been claimed by a plugin |
| 207 | // and we are still in the initial input phase. |
| 208 | bool |
| 209 | should_defer_layout() const |
| 210 | { return !this->objects_.empty() && !this->in_replacement_phase_; } |
| 211 | |
| 212 | // Add a regular object to the deferred layout list. These are |
| 213 | // objects whose layout has been deferred until after the |
| 214 | // replacement files have arrived. |
| 215 | void |
| 216 | add_deferred_layout_object(Relobj* obj) |
| 217 | { this->deferred_layout_objects_.push_back(obj); } |
| 218 | |
| 219 | // Get input file information with an open (possibly re-opened) |
| 220 | // file descriptor. |
| 221 | ld_plugin_status |
| 222 | get_input_file(unsigned int handle, struct ld_plugin_input_file *file); |
| 223 | |
| 224 | // Release an input file. |
| 225 | ld_plugin_status |
| 226 | release_input_file(unsigned int handle); |
| 227 | |
| 228 | // Add a new input file. |
| 229 | ld_plugin_status |
| 230 | add_input_file(char *pathname); |
| 231 | |
| 232 | // Return TRUE if we are in the replacement phase. |
| 233 | bool |
| 234 | in_replacement_phase() const |
| 235 | { return this->in_replacement_phase_; } |
| 236 | |
| 237 | private: |
| 238 | Plugin_manager(const Plugin_manager&); |
| 239 | Plugin_manager& operator=(const Plugin_manager&); |
| 240 | |
| 241 | typedef std::list<Plugin*> Plugin_list; |
| 242 | typedef std::vector<Pluginobj*> Object_list; |
| 243 | typedef std::vector<Relobj*> Deferred_layout_list; |
| 244 | |
| 245 | // The list of plugin libraries. |
| 246 | Plugin_list plugins_; |
| 247 | // A pointer to the current plugin. Used while loading plugins. |
| 248 | Plugin_list::iterator current_; |
| 249 | |
| 250 | // The list of plugin objects. The index of an item in this list |
| 251 | // serves as the "handle" that we pass to the plugins. |
| 252 | Object_list objects_; |
| 253 | |
| 254 | // The list of regular objects whose layout has been deferred. |
| 255 | Deferred_layout_list deferred_layout_objects_; |
| 256 | |
| 257 | // The file currently up for claim by the plugins. |
| 258 | Input_file* input_file_; |
| 259 | struct ld_plugin_input_file plugin_input_file_; |
| 260 | |
| 261 | // TRUE after the all symbols read event; indicates that we are |
| 262 | // processing replacement files whose symbols should replace the |
| 263 | // placeholder symbols from the Pluginobj objects. |
| 264 | bool in_replacement_phase_; |
| 265 | |
| 266 | // TRUE if the cleanup handlers have been called. |
| 267 | bool cleanup_done_; |
| 268 | |
| 269 | const General_options& options_; |
| 270 | Workqueue* workqueue_; |
| 271 | Task* task_; |
| 272 | Input_objects* input_objects_; |
| 273 | Symbol_table* symtab_; |
| 274 | Layout* layout_; |
| 275 | Dirsearch* dirpath_; |
| 276 | Mapfile* mapfile_; |
| 277 | Task_token* this_blocker_; |
| 278 | }; |
| 279 | |
| 280 | |
| 281 | // An object file claimed by a plugin. This is an abstract base class. |
| 282 | // The implementation is the template class Sized_pluginobj. |
| 283 | |
| 284 | class Pluginobj : public Object |
| 285 | { |
| 286 | public: |
| 287 | |
| 288 | typedef std::vector<Symbol*> Symbols; |
| 289 | |
| 290 | Pluginobj(const std::string& name, Input_file* input_file, off_t offset, |
| 291 | off_t filesize); |
| 292 | |
| 293 | // Fill in the symbol resolution status for the given plugin symbols. |
| 294 | ld_plugin_status |
| 295 | get_symbol_resolution_info(int nsyms, ld_plugin_symbol* syms) const; |
| 296 | |
| 297 | // Store the incoming symbols from the plugin for later processing. |
| 298 | void |
| 299 | store_incoming_symbols(int nsyms, const struct ld_plugin_symbol* syms) |
| 300 | { |
| 301 | this->nsyms_ = nsyms; |
| 302 | this->syms_ = syms; |
| 303 | } |
| 304 | |
| 305 | // Return TRUE if the comdat group with key COMDAT_KEY from this object |
| 306 | // should be kept. |
| 307 | bool |
| 308 | include_comdat_group(std::string comdat_key, Layout* layout); |
| 309 | |
| 310 | // Return the filename. |
| 311 | const std::string& |
| 312 | filename() const |
| 313 | { return this->input_file()->filename(); } |
| 314 | |
| 315 | // Return the file descriptor. |
| 316 | int |
| 317 | descriptor() |
| 318 | { return this->input_file()->file().descriptor(); } |
| 319 | |
| 320 | // Return the size of the file or archive member. |
| 321 | off_t |
| 322 | filesize() |
| 323 | { return this->filesize_; } |
| 324 | |
| 325 | protected: |
| 326 | // Return TRUE if this is an object claimed by a plugin. |
| 327 | virtual Pluginobj* |
| 328 | do_pluginobj() |
| 329 | { return this; } |
| 330 | |
| 331 | // The number of symbols provided by the plugin. |
| 332 | int nsyms_; |
| 333 | |
| 334 | // The symbols provided by the plugin. |
| 335 | const struct ld_plugin_symbol* syms_; |
| 336 | |
| 337 | // The entries in the symbol table for the external symbols. |
| 338 | Symbols symbols_; |
| 339 | |
| 340 | private: |
| 341 | // Size of the file (or archive member). |
| 342 | off_t filesize_; |
| 343 | // Map a comdat key symbol to a boolean indicating whether the comdat |
| 344 | // group in this object with that key should be kept. |
| 345 | typedef Unordered_map<std::string, bool> Comdat_map; |
| 346 | Comdat_map comdat_map_; |
| 347 | }; |
| 348 | |
| 349 | // A plugin object, size-specific version. |
| 350 | |
| 351 | template<int size, bool big_endian> |
| 352 | class Sized_pluginobj : public Pluginobj |
| 353 | { |
| 354 | public: |
| 355 | Sized_pluginobj(const std::string& name, Input_file* input_file, |
| 356 | off_t offset, off_t filesize); |
| 357 | |
| 358 | // Read the symbols. |
| 359 | void |
| 360 | do_read_symbols(Read_symbols_data*); |
| 361 | |
| 362 | // Lay out the input sections. |
| 363 | void |
| 364 | do_layout(Symbol_table*, Layout*, Read_symbols_data*); |
| 365 | |
| 366 | // Add the symbols to the symbol table. |
| 367 | void |
| 368 | do_add_symbols(Symbol_table*, Read_symbols_data*, Layout*); |
| 369 | |
| 370 | // Get the size of a section. |
| 371 | uint64_t |
| 372 | do_section_size(unsigned int shndx); |
| 373 | |
| 374 | // Get the name of a section. |
| 375 | std::string |
| 376 | do_section_name(unsigned int shndx); |
| 377 | |
| 378 | // Return a view of the contents of a section. |
| 379 | Object::Location |
| 380 | do_section_contents(unsigned int shndx); |
| 381 | |
| 382 | // Return section flags. |
| 383 | uint64_t |
| 384 | do_section_flags(unsigned int shndx); |
| 385 | |
| 386 | // Return section address. |
| 387 | uint64_t |
| 388 | do_section_address(unsigned int shndx); |
| 389 | |
| 390 | // Return section type. |
| 391 | unsigned int |
| 392 | do_section_type(unsigned int shndx); |
| 393 | |
| 394 | // Return the section link field. |
| 395 | unsigned int |
| 396 | do_section_link(unsigned int shndx); |
| 397 | |
| 398 | // Return the section link field. |
| 399 | unsigned int |
| 400 | do_section_info(unsigned int shndx); |
| 401 | |
| 402 | // Return the section alignment. |
| 403 | uint64_t |
| 404 | do_section_addralign(unsigned int shndx); |
| 405 | |
| 406 | // Return the Xindex structure to use. |
| 407 | Xindex* |
| 408 | do_initialize_xindex(); |
| 409 | |
| 410 | // Get symbol counts. |
| 411 | void |
| 412 | do_get_global_symbol_counts(const Symbol_table*, size_t*, size_t*) const; |
| 413 | |
| 414 | // Add placeholder symbols from a claimed file. |
| 415 | ld_plugin_status |
| 416 | add_symbols_from_plugin(int nsyms, const ld_plugin_symbol* syms); |
| 417 | |
| 418 | protected: |
| 419 | |
| 420 | private: |
| 421 | }; |
| 422 | |
| 423 | // This Task handles handles the "all symbols read" event hook. |
| 424 | // The plugin may add additional input files at this time, which must |
| 425 | // be queued for reading. |
| 426 | |
| 427 | class Plugin_hook : public Task |
| 428 | { |
| 429 | public: |
| 430 | Plugin_hook(const General_options& options, Input_objects* input_objects, |
| 431 | Symbol_table* symtab, Layout* layout, Dirsearch* dirpath, |
| 432 | Mapfile* mapfile, Task_token* this_blocker, |
| 433 | Task_token* next_blocker) |
| 434 | : options_(options), input_objects_(input_objects), symtab_(symtab), |
| 435 | layout_(layout), dirpath_(dirpath), mapfile_(mapfile), |
| 436 | this_blocker_(this_blocker), next_blocker_(next_blocker) |
| 437 | { } |
| 438 | |
| 439 | ~Plugin_hook(); |
| 440 | |
| 441 | // The standard Task methods. |
| 442 | |
| 443 | Task_token* |
| 444 | is_runnable(); |
| 445 | |
| 446 | void |
| 447 | locks(Task_locker*); |
| 448 | |
| 449 | void |
| 450 | run(Workqueue*); |
| 451 | |
| 452 | std::string |
| 453 | get_name() const |
| 454 | { return "Plugin_hook"; } |
| 455 | |
| 456 | private: |
| 457 | const General_options& options_; |
| 458 | Input_objects* input_objects_; |
| 459 | Symbol_table* symtab_; |
| 460 | Layout* layout_; |
| 461 | Dirsearch* dirpath_; |
| 462 | Mapfile* mapfile_; |
| 463 | Task_token* this_blocker_; |
| 464 | Task_token* next_blocker_; |
| 465 | }; |
| 466 | |
| 467 | } // End namespace gold. |
| 468 | |
| 469 | #endif // !defined(GOLD_PLUGIN_H) |