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5d3236ee DK |
1 | /* Plugin control for the GNU linker. |
2 | Copyright 2010 Free Software Foundation, Inc. | |
3 | ||
4 | This file is part of the GNU Binutils. | |
5 | ||
6 | This program is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 3 of the License, or | |
9 | (at your option) any later version. | |
10 | ||
11 | This program is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with this program; if not, write to the Free Software | |
18 | Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, | |
19 | MA 02110-1301, USA. */ | |
20 | ||
21 | #include "sysdep.h" | |
22 | #include "libiberty.h" | |
23 | #include "bfd.h" | |
24 | #include "bfdlink.h" | |
25 | #include "bfdver.h" | |
26 | #include "ld.h" | |
27 | #include "ldmain.h" | |
28 | #include "ldmisc.h" | |
29 | #include "ldexp.h" | |
30 | #include "ldlang.h" | |
31 | #include "ldfile.h" | |
32 | #include "plugin.h" | |
33 | #include "plugin-api.h" | |
34 | #include "elf-bfd.h" | |
3917d5d5 DK |
35 | #if !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H) |
36 | #include <Windows.h> | |
37 | #endif | |
5d3236ee DK |
38 | |
39 | /* The suffix to append to the name of the real (claimed) object file | |
40 | when generating a dummy BFD to hold the IR symbols sent from the | |
41 | plugin. */ | |
42 | #define IRONLY_SUFFIX ".ironly\004" | |
43 | ||
44 | /* This is sizeof an array of chars, not sizeof a const char *. We | |
45 | also have to avoid inadvertently counting the trailing NUL. */ | |
46 | #define IRONLY_SUFFIX_LEN (sizeof (IRONLY_SUFFIX) - 1) | |
47 | ||
48 | /* Stores a single argument passed to a plugin. */ | |
49 | typedef struct plugin_arg | |
50 | { | |
51 | struct plugin_arg *next; | |
52 | const char *arg; | |
53 | } plugin_arg_t; | |
54 | ||
55 | /* Holds all details of a single plugin. */ | |
56 | typedef struct plugin | |
57 | { | |
58 | /* Next on the list of plugins, or NULL at end of chain. */ | |
59 | struct plugin *next; | |
60 | /* The argument string given to --plugin. */ | |
61 | const char *name; | |
62 | /* The shared library handle returned by dlopen. */ | |
63 | void *dlhandle; | |
64 | /* The list of argument string given to --plugin-opt. */ | |
65 | plugin_arg_t *args; | |
66 | /* Number of args in the list, for convenience. */ | |
67 | size_t n_args; | |
68 | /* The plugin's event handlers. */ | |
69 | ld_plugin_claim_file_handler claim_file_handler; | |
70 | ld_plugin_all_symbols_read_handler all_symbols_read_handler; | |
71 | ld_plugin_cleanup_handler cleanup_handler; | |
72 | /* TRUE if the cleanup handlers have been called. */ | |
73 | bfd_boolean cleanup_done; | |
74 | } plugin_t; | |
75 | ||
76 | /* The master list of all plugins. */ | |
77 | static plugin_t *plugins_list = NULL; | |
78 | ||
79 | /* We keep a tail pointer for easy linking on the end. */ | |
80 | static plugin_t **plugins_tail_chain_ptr = &plugins_list; | |
81 | ||
82 | /* The last plugin added to the list, for receiving args. */ | |
83 | static plugin_t *last_plugin = NULL; | |
84 | ||
85 | /* The tail of the arg chain of the last plugin added to the list. */ | |
86 | static plugin_arg_t **last_plugin_args_tail_chain_ptr = NULL; | |
87 | ||
88 | /* The plugin which is currently having a callback executed. */ | |
89 | static plugin_t *called_plugin = NULL; | |
90 | ||
91 | /* Last plugin to cause an error, if any. */ | |
92 | static const char *error_plugin = NULL; | |
93 | ||
94 | /* A hash table that records symbols referenced by non-IR files. Used | |
95 | at get_symbols time to determine whether any prevailing defs from | |
96 | IR files are referenced only from other IR files, so tthat we can | |
97 | we can distinguish the LDPR_PREVAILING_DEF and LDPR_PREVAILING_DEF_IRONLY | |
98 | cases when establishing symbol resolutions. */ | |
99 | static struct bfd_hash_table *non_ironly_hash = NULL; | |
100 | ||
101 | /* Set at all symbols read time, to avoid recursively offering the plugin | |
102 | its own newly-added input files and libs to claim. */ | |
103 | static bfd_boolean no_more_claiming = FALSE; | |
104 | ||
105 | /* If the --allow-multiple-definition command-line option is active, we | |
106 | have to disable it so that BFD always calls our hook, and simulate the | |
107 | effect (when not resolving IR vs. real symbols) ourselves by ensuring | |
108 | TRUE is returned from the hook. */ | |
109 | static bfd_boolean plugin_cached_allow_multiple_defs = FALSE; | |
110 | ||
e73d965c L |
111 | /* Call 'cleanup' hook for all plugins at exit. */ |
112 | static void plugin_call_cleanup (void); | |
113 | ||
5d3236ee DK |
114 | /* List of tags to set in the constant leading part of the tv array. */ |
115 | static const enum ld_plugin_tag tv_header_tags[] = | |
116 | { | |
117 | LDPT_MESSAGE, | |
118 | LDPT_API_VERSION, | |
119 | LDPT_GNU_LD_VERSION, | |
120 | LDPT_LINKER_OUTPUT, | |
121 | LDPT_OUTPUT_NAME, | |
122 | LDPT_REGISTER_CLAIM_FILE_HOOK, | |
123 | LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK, | |
124 | LDPT_REGISTER_CLEANUP_HOOK, | |
125 | LDPT_ADD_SYMBOLS, | |
126 | LDPT_GET_INPUT_FILE, | |
127 | LDPT_RELEASE_INPUT_FILE, | |
128 | LDPT_GET_SYMBOLS, | |
129 | LDPT_ADD_INPUT_FILE, | |
130 | LDPT_ADD_INPUT_LIBRARY, | |
131 | LDPT_SET_EXTRA_LIBRARY_PATH | |
132 | }; | |
133 | ||
134 | /* How many entries in the constant leading part of the tv array. */ | |
135 | static const size_t tv_header_size = ARRAY_SIZE (tv_header_tags); | |
136 | ||
3917d5d5 DK |
137 | #if !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H) |
138 | ||
139 | #define RTLD_NOW 0 /* Dummy value. */ | |
140 | ||
141 | static void * | |
142 | dlopen (const char *file, int mode ATTRIBUTE_UNUSED) | |
143 | { | |
144 | return LoadLibrary (file); | |
145 | } | |
146 | ||
147 | static void * | |
148 | dlsym (void *handle, const char *name) | |
149 | { | |
150 | return GetProcAddress (handle, name); | |
151 | } | |
152 | ||
153 | static int | |
154 | dlclose (void *handle) | |
155 | { | |
156 | FreeLibrary (handle); | |
157 | return 0; | |
158 | } | |
159 | ||
160 | #endif /* !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H) */ | |
161 | ||
5d3236ee DK |
162 | /* Helper function for exiting with error status. */ |
163 | static int | |
164 | set_plugin_error (const char *plugin) | |
165 | { | |
166 | error_plugin = plugin; | |
167 | return -1; | |
168 | } | |
169 | ||
170 | /* Test if an error occurred. */ | |
171 | static bfd_boolean | |
172 | plugin_error_p (void) | |
173 | { | |
174 | return error_plugin != NULL; | |
175 | } | |
176 | ||
177 | /* Return name of plugin which caused an error if any. */ | |
d44ad554 DK |
178 | const char * |
179 | plugin_error_plugin (void) | |
5d3236ee DK |
180 | { |
181 | return error_plugin ? error_plugin : _("<no plugin>"); | |
182 | } | |
183 | ||
184 | /* Handle -plugin arg: find and load plugin, or return error. */ | |
d44ad554 DK |
185 | int |
186 | plugin_opt_plugin (const char *plugin) | |
5d3236ee DK |
187 | { |
188 | plugin_t *newplug; | |
189 | ||
190 | newplug = xmalloc (sizeof *newplug); | |
191 | memset (newplug, 0, sizeof *newplug); | |
192 | newplug->name = plugin; | |
193 | newplug->dlhandle = dlopen (plugin, RTLD_NOW); | |
194 | if (!newplug->dlhandle) | |
195 | return set_plugin_error (plugin); | |
196 | ||
197 | /* Chain on end, so when we run list it is in command-line order. */ | |
198 | *plugins_tail_chain_ptr = newplug; | |
199 | plugins_tail_chain_ptr = &newplug->next; | |
200 | ||
201 | /* Record it as current plugin for receiving args. */ | |
202 | last_plugin = newplug; | |
203 | last_plugin_args_tail_chain_ptr = &newplug->args; | |
204 | return 0; | |
205 | } | |
206 | ||
207 | /* Accumulate option arguments for last-loaded plugin, or return | |
208 | error if none. */ | |
d44ad554 DK |
209 | int |
210 | plugin_opt_plugin_arg (const char *arg) | |
5d3236ee DK |
211 | { |
212 | plugin_arg_t *newarg; | |
213 | ||
214 | if (!last_plugin) | |
215 | return set_plugin_error (_("<no plugin>")); | |
216 | ||
217 | newarg = xmalloc (sizeof *newarg); | |
218 | newarg->arg = arg; | |
219 | newarg->next = NULL; | |
220 | ||
221 | /* Chain on end to preserve command-line order. */ | |
222 | *last_plugin_args_tail_chain_ptr = newarg; | |
223 | last_plugin_args_tail_chain_ptr = &newarg->next; | |
224 | last_plugin->n_args++; | |
225 | return 0; | |
226 | } | |
227 | ||
228 | /* Create a dummy BFD. */ | |
229 | bfd * | |
230 | plugin_get_ir_dummy_bfd (const char *name, bfd *srctemplate) | |
231 | { | |
232 | asection *sec; | |
bc110b6e AM |
233 | bfd *abfd; |
234 | ||
235 | bfd_use_reserved_id = 1; | |
236 | abfd = bfd_create (concat (name, IRONLY_SUFFIX, (const char *)NULL), | |
237 | srctemplate); | |
5d3236ee DK |
238 | bfd_set_arch_info (abfd, bfd_get_arch_info (srctemplate)); |
239 | bfd_make_writable (abfd); | |
240 | /* Create a minimal set of sections to own the symbols. */ | |
241 | sec = bfd_make_section_old_way (abfd, ".text"); | |
242 | bfd_set_section_flags (abfd, sec, | |
bc110b6e AM |
243 | (SEC_CODE | SEC_HAS_CONTENTS | SEC_READONLY |
244 | | SEC_ALLOC | SEC_LOAD | SEC_KEEP)); | |
5d3236ee DK |
245 | sec->output_section = sec; |
246 | sec->output_offset = 0; | |
247 | return abfd; | |
248 | } | |
249 | ||
d44ad554 DK |
250 | /* Check if the BFD passed in is an IR dummy object file. */ |
251 | static bfd_boolean | |
5d3236ee DK |
252 | is_ir_dummy_bfd (const bfd *abfd) |
253 | { | |
129b5d55 AM |
254 | size_t namlen; |
255 | ||
256 | if (abfd == NULL) | |
257 | return FALSE; | |
258 | namlen = strlen (abfd->filename); | |
5d3236ee DK |
259 | if (namlen < IRONLY_SUFFIX_LEN) |
260 | return FALSE; | |
261 | return !strcmp (abfd->filename + namlen - IRONLY_SUFFIX_LEN, IRONLY_SUFFIX); | |
262 | } | |
263 | ||
264 | /* Helpers to convert between BFD and GOLD symbol formats. */ | |
265 | static enum ld_plugin_status | |
266 | asymbol_from_plugin_symbol (bfd *abfd, asymbol *asym, | |
f84854b6 | 267 | const struct ld_plugin_symbol *ldsym) |
5d3236ee DK |
268 | { |
269 | flagword flags = BSF_NO_FLAGS; | |
270 | struct bfd_section *section; | |
271 | ||
272 | asym->the_bfd = abfd; | |
f84854b6 | 273 | asym->name = (ldsym->version |
5d3236ee | 274 | ? concat (ldsym->name, "@", ldsym->version, NULL) |
f84854b6 | 275 | : ldsym->name); |
5d3236ee DK |
276 | asym->value = 0; |
277 | switch (ldsym->def) | |
278 | { | |
279 | case LDPK_WEAKDEF: | |
280 | flags = BSF_WEAK; | |
281 | /* FALLTHRU */ | |
282 | case LDPK_DEF: | |
283 | flags |= BSF_GLOBAL; | |
284 | section = bfd_get_section_by_name (abfd, ".text"); | |
285 | break; | |
286 | ||
287 | case LDPK_WEAKUNDEF: | |
288 | flags = BSF_WEAK; | |
289 | /* FALLTHRU */ | |
290 | case LDPK_UNDEF: | |
291 | section = bfd_und_section_ptr; | |
292 | break; | |
293 | ||
294 | case LDPK_COMMON: | |
295 | flags = BSF_GLOBAL; | |
296 | section = bfd_com_section_ptr; | |
297 | asym->value = ldsym->size; | |
5c08b7d4 L |
298 | /* For ELF targets, set alignment of common symbol to 1. */ |
299 | if (bfd_get_flavour (abfd) == bfd_target_elf_flavour) | |
300 | ((elf_symbol_type *) asym)->internal_elf_sym.st_value = 1; | |
5d3236ee DK |
301 | break; |
302 | ||
303 | default: | |
304 | return LDPS_ERR; | |
305 | } | |
306 | asym->flags = flags; | |
307 | asym->section = section; | |
308 | ||
309 | /* Visibility only applies on ELF targets. */ | |
310 | if (bfd_get_flavour (abfd) == bfd_target_elf_flavour) | |
311 | { | |
312 | elf_symbol_type *elfsym = elf_symbol_from (abfd, asym); | |
cfac8028 L |
313 | unsigned char visibility; |
314 | ||
5d3236ee | 315 | if (!elfsym) |
ea360572 | 316 | einfo (_("%P%F: %s: non-ELF symbol in ELF BFD!\n"), asym->name); |
cfac8028 L |
317 | switch (ldsym->visibility) |
318 | { | |
319 | default: | |
ea360572 | 320 | einfo (_("%P%F: unknown ELF symbol visibility: %d!\n"), |
cfac8028 L |
321 | ldsym->visibility); |
322 | case LDPV_DEFAULT: | |
323 | visibility = STV_DEFAULT; | |
324 | break; | |
325 | case LDPV_PROTECTED: | |
326 | visibility = STV_PROTECTED; | |
327 | break; | |
328 | case LDPV_INTERNAL: | |
329 | visibility = STV_INTERNAL; | |
330 | break; | |
331 | case LDPV_HIDDEN: | |
332 | visibility = STV_HIDDEN; | |
333 | break; | |
334 | } | |
335 | elfsym->internal_elf_sym.st_other | |
336 | = (visibility | (elfsym->internal_elf_sym.st_other | |
337 | & ~ELF_ST_VISIBILITY (-1))); | |
5d3236ee DK |
338 | } |
339 | ||
340 | return LDPS_OK; | |
341 | } | |
342 | ||
343 | /* Register a claim-file handler. */ | |
344 | static enum ld_plugin_status | |
345 | register_claim_file (ld_plugin_claim_file_handler handler) | |
346 | { | |
347 | ASSERT (called_plugin); | |
348 | called_plugin->claim_file_handler = handler; | |
349 | return LDPS_OK; | |
350 | } | |
351 | ||
352 | /* Register an all-symbols-read handler. */ | |
353 | static enum ld_plugin_status | |
354 | register_all_symbols_read (ld_plugin_all_symbols_read_handler handler) | |
355 | { | |
356 | ASSERT (called_plugin); | |
357 | called_plugin->all_symbols_read_handler = handler; | |
358 | return LDPS_OK; | |
359 | } | |
360 | ||
361 | /* Register a cleanup handler. */ | |
362 | static enum ld_plugin_status | |
363 | register_cleanup (ld_plugin_cleanup_handler handler) | |
364 | { | |
365 | ASSERT (called_plugin); | |
366 | called_plugin->cleanup_handler = handler; | |
367 | return LDPS_OK; | |
368 | } | |
369 | ||
370 | /* Add symbols from a plugin-claimed input file. */ | |
371 | static enum ld_plugin_status | |
372 | add_symbols (void *handle, int nsyms, const struct ld_plugin_symbol *syms) | |
373 | { | |
374 | asymbol **symptrs; | |
375 | bfd *abfd = handle; | |
376 | int n; | |
377 | ASSERT (called_plugin); | |
378 | symptrs = xmalloc (nsyms * sizeof *symptrs); | |
379 | for (n = 0; n < nsyms; n++) | |
380 | { | |
381 | enum ld_plugin_status rv; | |
382 | asymbol *bfdsym = bfd_make_empty_symbol (abfd); | |
383 | symptrs[n] = bfdsym; | |
384 | rv = asymbol_from_plugin_symbol (abfd, bfdsym, syms + n); | |
385 | if (rv != LDPS_OK) | |
386 | return rv; | |
387 | } | |
388 | bfd_set_symtab (abfd, symptrs, nsyms); | |
389 | return LDPS_OK; | |
390 | } | |
391 | ||
392 | /* Get the input file information with an open (possibly re-opened) | |
393 | file descriptor. */ | |
394 | static enum ld_plugin_status | |
395 | get_input_file (const void *handle, struct ld_plugin_input_file *file) | |
396 | { | |
397 | ASSERT (called_plugin); | |
398 | handle = handle; | |
399 | file = file; | |
400 | return LDPS_ERR; | |
401 | } | |
402 | ||
403 | /* Release the input file. */ | |
404 | static enum ld_plugin_status | |
405 | release_input_file (const void *handle) | |
406 | { | |
407 | ASSERT (called_plugin); | |
408 | handle = handle; | |
409 | return LDPS_ERR; | |
410 | } | |
411 | ||
42a851a9 DK |
412 | /* Return TRUE if a defined symbol might be reachable from outside the |
413 | universe of claimed objects. */ | |
414 | static inline bfd_boolean | |
415 | is_visible_from_outside (struct ld_plugin_symbol *lsym, asection *section, | |
f84854b6 | 416 | struct bfd_link_hash_entry *blhe) |
42a851a9 DK |
417 | { |
418 | /* Section's owner may be NULL if it is the absolute | |
419 | section, fortunately is_ir_dummy_bfd handles that. */ | |
420 | if (!is_ir_dummy_bfd (section->owner)) | |
421 | return TRUE; | |
422 | if (link_info.relocatable) | |
423 | return TRUE; | |
424 | if (link_info.export_dynamic || link_info.shared) | |
425 | { | |
426 | /* Only ELF symbols really have visibility. */ | |
427 | if (bfd_get_flavour (link_info.output_bfd) == bfd_target_elf_flavour) | |
428 | { | |
429 | struct elf_link_hash_entry *el = (struct elf_link_hash_entry *)blhe; | |
430 | int vis = ELF_ST_VISIBILITY (el->other); | |
431 | return vis == STV_DEFAULT || vis == STV_PROTECTED; | |
432 | } | |
433 | /* On non-ELF targets, we can safely make inferences by considering | |
f84854b6 | 434 | what visibility the plugin would have liked to apply when it first |
42a851a9 DK |
435 | sent us the symbol. During ELF symbol processing, visibility only |
436 | ever becomes more restrictive, not less, when symbols are merged, | |
437 | so this is a conservative estimate; it may give false positives, | |
438 | declaring something visible from outside when it in fact would | |
439 | not have been, but this will only lead to missed optimisation | |
440 | opportunities during LTRANS at worst; it will not give false | |
441 | negatives, which can lead to the disastrous conclusion that the | |
442 | related symbol is IRONLY. (See GCC PR46319 for an example.) */ | |
cfac8028 L |
443 | return (lsym->visibility == LDPV_DEFAULT |
444 | || lsym->visibility == LDPV_PROTECTED); | |
42a851a9 DK |
445 | } |
446 | return FALSE; | |
447 | } | |
448 | ||
5d3236ee DK |
449 | /* Get the symbol resolution info for a plugin-claimed input file. */ |
450 | static enum ld_plugin_status | |
451 | get_symbols (const void *handle, int nsyms, struct ld_plugin_symbol *syms) | |
452 | { | |
453 | const bfd *abfd = handle; | |
454 | int n; | |
455 | ASSERT (called_plugin); | |
456 | for (n = 0; n < nsyms; n++) | |
457 | { | |
458 | struct bfd_link_hash_entry *blhe; | |
459 | bfd_boolean ironly; | |
42a851a9 | 460 | asection *owner_sec; |
5d3236ee DK |
461 | |
462 | blhe = bfd_link_hash_lookup (link_info.hash, syms[n].name, | |
f84854b6 | 463 | FALSE, FALSE, TRUE); |
5d3236ee DK |
464 | if (!blhe) |
465 | { | |
466 | syms[n].resolution = LDPR_UNKNOWN; | |
467 | continue; | |
468 | } | |
469 | ||
470 | /* Determine resolution from blhe type and symbol's original type. */ | |
471 | if (blhe->type == bfd_link_hash_undefined | |
f84854b6 | 472 | || blhe->type == bfd_link_hash_undefweak) |
5d3236ee DK |
473 | { |
474 | syms[n].resolution = LDPR_UNDEF; | |
475 | continue; | |
476 | } | |
477 | if (blhe->type != bfd_link_hash_defined | |
f84854b6 L |
478 | && blhe->type != bfd_link_hash_defweak |
479 | && blhe->type != bfd_link_hash_common) | |
5d3236ee DK |
480 | { |
481 | /* We should not have a new, indirect or warning symbol here. */ | |
ea360572 | 482 | einfo ("%P%F: %s: plugin symbol table corrupt (sym type %d)\n", |
f84854b6 | 483 | called_plugin->name, blhe->type); |
5d3236ee DK |
484 | } |
485 | ||
42a851a9 DK |
486 | /* Find out which section owns the symbol. Since it's not undef, |
487 | it must have an owner; if it's not a common symbol, both defs | |
488 | and weakdefs keep it in the same place. */ | |
489 | owner_sec = (blhe->type == bfd_link_hash_common) | |
f84854b6 L |
490 | ? blhe->u.c.p->section |
491 | : blhe->u.def.section; | |
42a851a9 DK |
492 | |
493 | /* We need to know if the sym is referenced from non-IR files. Or | |
f84854b6 | 494 | even potentially-referenced, perhaps in a future final link if |
42a851a9 DK |
495 | this is a partial one, perhaps dynamically at load-time if the |
496 | symbol is externally visible. */ | |
497 | ironly = !is_visible_from_outside (&syms[n], owner_sec, blhe) | |
498 | && !bfd_hash_lookup (non_ironly_hash, syms[n].name, FALSE, FALSE); | |
5d3236ee DK |
499 | |
500 | /* If it was originally undefined or common, then it has been | |
f84854b6 L |
501 | resolved; determine how. */ |
502 | if (syms[n].def == LDPK_UNDEF | |
503 | || syms[n].def == LDPK_WEAKUNDEF | |
5d3236ee DK |
504 | || syms[n].def == LDPK_COMMON) |
505 | { | |
5d3236ee DK |
506 | if (owner_sec->owner == link_info.output_bfd) |
507 | syms[n].resolution = LDPR_RESOLVED_EXEC; | |
508 | else if (owner_sec->owner == abfd) | |
f84854b6 L |
509 | syms[n].resolution = (ironly |
510 | ? LDPR_PREVAILING_DEF_IRONLY | |
511 | : LDPR_PREVAILING_DEF); | |
5d3236ee DK |
512 | else if (is_ir_dummy_bfd (owner_sec->owner)) |
513 | syms[n].resolution = LDPR_RESOLVED_IR; | |
514 | else if (owner_sec->owner->flags & DYNAMIC) | |
515 | syms[n].resolution = LDPR_RESOLVED_DYN; | |
516 | else | |
517 | syms[n].resolution = LDPR_RESOLVED_EXEC; | |
518 | continue; | |
519 | } | |
520 | ||
521 | /* Was originally def, or weakdef. Does it prevail? If the | |
f84854b6 | 522 | owner is the original dummy bfd that supplied it, then this |
5d3236ee | 523 | is the definition that has prevailed. */ |
42a851a9 | 524 | if (owner_sec->owner == link_info.output_bfd) |
5d3236ee | 525 | syms[n].resolution = LDPR_PREEMPTED_REG; |
42a851a9 | 526 | else if (owner_sec->owner == abfd) |
5d3236ee | 527 | { |
f84854b6 | 528 | syms[n].resolution = (ironly |
5d3236ee | 529 | ? LDPR_PREVAILING_DEF_IRONLY |
f84854b6 | 530 | : LDPR_PREVAILING_DEF); |
5d3236ee DK |
531 | continue; |
532 | } | |
533 | ||
534 | /* Was originally def, weakdef, or common, but has been pre-empted. */ | |
42a851a9 | 535 | syms[n].resolution = is_ir_dummy_bfd (owner_sec->owner) |
f84854b6 L |
536 | ? LDPR_PREEMPTED_IR |
537 | : LDPR_PREEMPTED_REG; | |
5d3236ee DK |
538 | } |
539 | return LDPS_OK; | |
540 | } | |
541 | ||
542 | /* Add a new (real) input file generated by a plugin. */ | |
543 | static enum ld_plugin_status | |
544 | add_input_file (const char *pathname) | |
545 | { | |
546 | ASSERT (called_plugin); | |
d4cb7acd | 547 | if (!lang_add_input_file (xstrdup (pathname), lang_input_file_is_file_enum, |
f84854b6 | 548 | NULL)) |
5d3236ee DK |
549 | return LDPS_ERR; |
550 | return LDPS_OK; | |
551 | } | |
552 | ||
553 | /* Add a new (real) library required by a plugin. */ | |
554 | static enum ld_plugin_status | |
555 | add_input_library (const char *pathname) | |
556 | { | |
557 | ASSERT (called_plugin); | |
d4cb7acd | 558 | if (!lang_add_input_file (xstrdup (pathname), lang_input_file_is_l_enum, |
f84854b6 | 559 | NULL)) |
5d3236ee DK |
560 | return LDPS_ERR; |
561 | return LDPS_OK; | |
562 | } | |
563 | ||
564 | /* Set the extra library path to be used by libraries added via | |
565 | add_input_library. */ | |
566 | static enum ld_plugin_status | |
567 | set_extra_library_path (const char *path) | |
568 | { | |
569 | ASSERT (called_plugin); | |
d4cb7acd | 570 | ldfile_add_library_path (xstrdup (path), FALSE); |
5d3236ee DK |
571 | return LDPS_OK; |
572 | } | |
573 | ||
574 | /* Issue a diagnostic message from a plugin. */ | |
575 | static enum ld_plugin_status | |
576 | message (int level, const char *format, ...) | |
577 | { | |
578 | va_list args; | |
579 | va_start (args, format); | |
580 | ||
581 | switch (level) | |
582 | { | |
583 | case LDPL_INFO: | |
584 | vfinfo (stdout, format, args, FALSE); | |
585 | break; | |
586 | case LDPL_WARNING: | |
587 | vfinfo (stdout, format, args, TRUE); | |
588 | break; | |
589 | case LDPL_FATAL: | |
590 | case LDPL_ERROR: | |
591 | default: | |
f84854b6 | 592 | { |
7990daec L |
593 | char *newfmt = ACONCAT ((level == LDPL_FATAL |
594 | ? "%P%F: " : "%P%X: ", | |
b7f42144 | 595 | format, "\n", NULL)); |
f84854b6 L |
596 | vfinfo (stderr, newfmt, args, TRUE); |
597 | } | |
5d3236ee DK |
598 | break; |
599 | } | |
600 | ||
d9b21463 | 601 | putchar('\n'); |
b7f42144 | 602 | |
5d3236ee DK |
603 | va_end (args); |
604 | return LDPS_OK; | |
605 | } | |
606 | ||
607 | /* Helper to size leading part of tv array and set it up. */ | |
608 | static size_t | |
609 | set_tv_header (struct ld_plugin_tv *tv) | |
610 | { | |
611 | size_t i; | |
612 | ||
613 | /* Version info. */ | |
614 | static const unsigned int major = (unsigned)(BFD_VERSION / 100000000UL); | |
615 | static const unsigned int minor = (unsigned)(BFD_VERSION / 1000000UL) % 100; | |
616 | ||
617 | if (!tv) | |
618 | return tv_header_size; | |
619 | ||
620 | for (i = 0; i < tv_header_size; i++) | |
621 | { | |
622 | tv[i].tv_tag = tv_header_tags[i]; | |
623 | #define TVU(x) tv[i].tv_u.tv_ ## x | |
624 | switch (tv[i].tv_tag) | |
625 | { | |
f84854b6 L |
626 | case LDPT_MESSAGE: |
627 | TVU(message) = message; | |
628 | break; | |
629 | case LDPT_API_VERSION: | |
630 | TVU(val) = LD_PLUGIN_API_VERSION; | |
631 | break; | |
632 | case LDPT_GNU_LD_VERSION: | |
633 | TVU(val) = major * 100 + minor; | |
634 | break; | |
635 | case LDPT_LINKER_OUTPUT: | |
636 | TVU(val) = (link_info.relocatable | |
637 | ? LDPO_REL | |
638 | : (link_info.shared ? LDPO_DYN : LDPO_EXEC)); | |
639 | break; | |
640 | case LDPT_OUTPUT_NAME: | |
641 | TVU(string) = output_filename; | |
642 | break; | |
643 | case LDPT_REGISTER_CLAIM_FILE_HOOK: | |
644 | TVU(register_claim_file) = register_claim_file; | |
645 | break; | |
646 | case LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK: | |
647 | TVU(register_all_symbols_read) = register_all_symbols_read; | |
648 | break; | |
649 | case LDPT_REGISTER_CLEANUP_HOOK: | |
650 | TVU(register_cleanup) = register_cleanup; | |
651 | break; | |
652 | case LDPT_ADD_SYMBOLS: | |
653 | TVU(add_symbols) = add_symbols; | |
654 | break; | |
655 | case LDPT_GET_INPUT_FILE: | |
656 | TVU(get_input_file) = get_input_file; | |
657 | break; | |
658 | case LDPT_RELEASE_INPUT_FILE: | |
659 | TVU(release_input_file) = release_input_file; | |
660 | break; | |
661 | case LDPT_GET_SYMBOLS: | |
662 | TVU(get_symbols) = get_symbols; | |
663 | break; | |
664 | case LDPT_ADD_INPUT_FILE: | |
665 | TVU(add_input_file) = add_input_file; | |
666 | break; | |
667 | case LDPT_ADD_INPUT_LIBRARY: | |
668 | TVU(add_input_library) = add_input_library; | |
669 | break; | |
670 | case LDPT_SET_EXTRA_LIBRARY_PATH: | |
671 | TVU(set_extra_library_path) = set_extra_library_path; | |
672 | break; | |
673 | default: | |
674 | /* Added a new entry to the array without adding | |
675 | a new case to set up its value is a bug. */ | |
676 | FAIL (); | |
5d3236ee DK |
677 | } |
678 | #undef TVU | |
679 | } | |
680 | return tv_header_size; | |
681 | } | |
682 | ||
683 | /* Append the per-plugin args list and trailing LDPT_NULL to tv. */ | |
684 | static void | |
685 | set_tv_plugin_args (plugin_t *plugin, struct ld_plugin_tv *tv) | |
686 | { | |
687 | plugin_arg_t *arg = plugin->args; | |
688 | while (arg) | |
689 | { | |
690 | tv->tv_tag = LDPT_OPTION; | |
691 | tv->tv_u.tv_string = arg->arg; | |
692 | arg = arg->next; | |
693 | tv++; | |
694 | } | |
695 | tv->tv_tag = LDPT_NULL; | |
696 | tv->tv_u.tv_val = 0; | |
697 | } | |
698 | ||
d44ad554 DK |
699 | /* Return true if any plugins are active this run. Only valid |
700 | after options have been processed. */ | |
701 | bfd_boolean | |
702 | plugin_active_plugins_p (void) | |
703 | { | |
704 | return plugins_list != NULL; | |
705 | } | |
706 | ||
5d3236ee | 707 | /* Load up and initialise all plugins after argument parsing. */ |
d44ad554 DK |
708 | int |
709 | plugin_load_plugins (void) | |
5d3236ee DK |
710 | { |
711 | struct ld_plugin_tv *my_tv; | |
712 | unsigned int max_args = 0; | |
713 | plugin_t *curplug = plugins_list; | |
714 | ||
715 | /* If there are no plugins, we need do nothing this run. */ | |
716 | if (!curplug) | |
717 | return 0; | |
718 | ||
e73d965c L |
719 | xatexit (plugin_call_cleanup); |
720 | ||
5d3236ee DK |
721 | /* First pass over plugins to find max # args needed so that we |
722 | can size and allocate the tv array. */ | |
723 | while (curplug) | |
724 | { | |
725 | if (curplug->n_args > max_args) | |
726 | max_args = curplug->n_args; | |
727 | curplug = curplug->next; | |
728 | } | |
729 | ||
730 | /* Allocate tv array and initialise constant part. */ | |
731 | my_tv = xmalloc ((max_args + 1 + tv_header_size) * sizeof *my_tv); | |
732 | set_tv_header (my_tv); | |
733 | ||
734 | /* Pass over plugins again, activating them. */ | |
735 | curplug = plugins_list; | |
736 | while (curplug) | |
737 | { | |
738 | enum ld_plugin_status rv; | |
739 | ld_plugin_onload onloadfn = dlsym (curplug->dlhandle, "onload"); | |
740 | if (!onloadfn) | |
741 | onloadfn = dlsym (curplug->dlhandle, "_onload"); | |
742 | if (!onloadfn) | |
f84854b6 | 743 | return set_plugin_error (curplug->name); |
5d3236ee DK |
744 | set_tv_plugin_args (curplug, &my_tv[tv_header_size]); |
745 | called_plugin = curplug; | |
746 | rv = (*onloadfn) (my_tv); | |
747 | called_plugin = NULL; | |
748 | if (rv != LDPS_OK) | |
f84854b6 | 749 | return set_plugin_error (curplug->name); |
5d3236ee DK |
750 | curplug = curplug->next; |
751 | } | |
752 | ||
753 | /* Since plugin(s) inited ok, assume they're going to want symbol | |
754 | resolutions, which needs us to track which symbols are referenced | |
755 | by non-IR files using the linker's notice callback. */ | |
756 | link_info.notice_all = TRUE; | |
757 | ||
758 | return 0; | |
759 | } | |
760 | ||
761 | /* Call 'claim file' hook for all plugins. */ | |
762 | int | |
763 | plugin_call_claim_file (const struct ld_plugin_input_file *file, int *claimed) | |
764 | { | |
765 | plugin_t *curplug = plugins_list; | |
766 | *claimed = FALSE; | |
767 | if (no_more_claiming) | |
768 | return 0; | |
769 | while (curplug && !*claimed) | |
770 | { | |
771 | if (curplug->claim_file_handler) | |
772 | { | |
773 | enum ld_plugin_status rv; | |
774 | called_plugin = curplug; | |
775 | rv = (*curplug->claim_file_handler) (file, claimed); | |
776 | called_plugin = NULL; | |
777 | if (rv != LDPS_OK) | |
778 | set_plugin_error (curplug->name); | |
779 | } | |
780 | curplug = curplug->next; | |
781 | } | |
782 | return plugin_error_p () ? -1 : 0; | |
783 | } | |
784 | ||
785 | /* Call 'all symbols read' hook for all plugins. */ | |
786 | int | |
787 | plugin_call_all_symbols_read (void) | |
788 | { | |
789 | plugin_t *curplug = plugins_list; | |
790 | ||
791 | /* Disable any further file-claiming. */ | |
792 | no_more_claiming = TRUE; | |
793 | ||
794 | /* If --allow-multiple-definition is in effect, we need to disable it, | |
795 | as the plugin infrastructure relies on the multiple_definition | |
796 | callback to swap out the dummy IR-only BFDs for new real ones | |
797 | when it starts opening the files added during this callback. */ | |
798 | plugin_cached_allow_multiple_defs = link_info.allow_multiple_definition; | |
799 | link_info.allow_multiple_definition = FALSE; | |
800 | ||
801 | while (curplug) | |
802 | { | |
803 | if (curplug->all_symbols_read_handler) | |
804 | { | |
805 | enum ld_plugin_status rv; | |
806 | called_plugin = curplug; | |
807 | rv = (*curplug->all_symbols_read_handler) (); | |
808 | called_plugin = NULL; | |
809 | if (rv != LDPS_OK) | |
810 | set_plugin_error (curplug->name); | |
811 | } | |
812 | curplug = curplug->next; | |
813 | } | |
814 | return plugin_error_p () ? -1 : 0; | |
815 | } | |
816 | ||
e73d965c L |
817 | /* Call 'cleanup' hook for all plugins at exit. */ |
818 | static void | |
5d3236ee DK |
819 | plugin_call_cleanup (void) |
820 | { | |
821 | plugin_t *curplug = plugins_list; | |
822 | while (curplug) | |
823 | { | |
824 | if (curplug->cleanup_handler && !curplug->cleanup_done) | |
825 | { | |
826 | enum ld_plugin_status rv; | |
827 | curplug->cleanup_done = TRUE; | |
828 | called_plugin = curplug; | |
829 | rv = (*curplug->cleanup_handler) (); | |
830 | called_plugin = NULL; | |
831 | if (rv != LDPS_OK) | |
832 | set_plugin_error (curplug->name); | |
833 | dlclose (curplug->dlhandle); | |
834 | } | |
835 | curplug = curplug->next; | |
836 | } | |
e73d965c L |
837 | if (plugin_error_p ()) |
838 | info_msg (_("%P: %s: error in plugin cleanup (ignored)\n"), | |
839 | plugin_error_plugin ()); | |
5d3236ee DK |
840 | } |
841 | ||
842 | /* Lazily init the non_ironly hash table. */ | |
843 | static void | |
844 | init_non_ironly_hash (void) | |
845 | { | |
846 | if (non_ironly_hash == NULL) | |
847 | { | |
848 | non_ironly_hash = | |
f84854b6 | 849 | (struct bfd_hash_table *) xmalloc (sizeof (struct bfd_hash_table)); |
5d3236ee DK |
850 | if (!bfd_hash_table_init_n (non_ironly_hash, |
851 | bfd_hash_newfunc, | |
852 | sizeof (struct bfd_hash_entry), | |
853 | 61)) | |
854 | einfo (_("%P%F: bfd_hash_table_init failed: %E\n")); | |
855 | } | |
856 | } | |
857 | ||
858 | /* To determine which symbols should be resolved LDPR_PREVAILING_DEF | |
859 | and which LDPR_PREVAILING_DEF_IRONLY, we notice all the symbols as | |
860 | the linker adds them to the linker hash table. If we see a symbol | |
861 | being referenced from a non-IR file, we add it to the non_ironly hash | |
862 | table. If we can't find it there at get_symbols time, we know that | |
863 | it was referenced only by IR files. We have to notice_all symbols, | |
864 | because we won't necessarily know until later which ones will be | |
865 | contributed by IR files. */ | |
866 | bfd_boolean | |
867 | plugin_notice (struct bfd_link_info *info ATTRIBUTE_UNUSED, | |
f84854b6 L |
868 | const char *name, bfd *abfd, |
869 | asection *section, bfd_vma value ATTRIBUTE_UNUSED) | |
5d3236ee DK |
870 | { |
871 | bfd_boolean is_ref = bfd_is_und_section (section); | |
872 | bfd_boolean is_dummy = is_ir_dummy_bfd (abfd); | |
873 | init_non_ironly_hash (); | |
874 | /* We only care about refs, not defs, indicated by section pointing | |
875 | to the undefined section (according to the bfd linker notice callback | |
876 | interface definition). */ | |
877 | if (is_ref && !is_dummy) | |
878 | { | |
879 | /* This is a ref from a non-IR file, so note the ref'd symbol | |
f84854b6 | 880 | in the non-IR-only hash. */ |
5d3236ee | 881 | if (!bfd_hash_lookup (non_ironly_hash, name, TRUE, TRUE)) |
ea360572 | 882 | einfo (_("%P%X: %s: hash table failure adding symbol %s\n"), |
f84854b6 | 883 | abfd->filename, name); |
5d3236ee DK |
884 | } |
885 | else if (!is_ref && is_dummy) | |
886 | { | |
887 | /* No further processing since this is a def from an IR dummy BFD. */ | |
888 | return FALSE; | |
889 | } | |
890 | ||
891 | /* Continue with cref/nocrossref/trace-sym processing. */ | |
892 | return TRUE; | |
893 | } | |
894 | ||
895 | /* When we add new object files to the link at all symbols read time, | |
896 | these contain the real code and symbols generated from the IR files, | |
897 | and so duplicate all the definitions already supplied by the dummy | |
898 | IR-only BFDs that we created at claim files time. We use the linker's | |
899 | multiple-definitions callback hook to fix up the clash, discarding | |
900 | the symbol from the IR-only BFD in favour of the symbol from the | |
901 | real BFD. We return true if this was not-really-a-clash because | |
902 | we've fixed it up, or anyway if --allow-multiple-definition was in | |
903 | effect (before we disabled it to ensure we got called back). */ | |
904 | bfd_boolean | |
905 | plugin_multiple_definition (struct bfd_link_info *info, const char *name, | |
f84854b6 L |
906 | bfd *obfd, asection *osec ATTRIBUTE_UNUSED, |
907 | bfd_vma oval ATTRIBUTE_UNUSED, | |
908 | bfd *nbfd, asection *nsec, bfd_vma nval) | |
5d3236ee DK |
909 | { |
910 | if (is_ir_dummy_bfd (obfd)) | |
911 | { | |
f84854b6 L |
912 | struct bfd_link_hash_entry *blhe |
913 | = bfd_link_hash_lookup (info->hash, name, FALSE, FALSE, FALSE); | |
5d3236ee | 914 | if (!blhe) |
ea360572 | 915 | einfo (_("%P%X: %s: can't find IR symbol '%s'\n"), nbfd->filename, |
f84854b6 | 916 | name); |
5d3236ee | 917 | else if (blhe->type != bfd_link_hash_defined) |
ea360572 | 918 | einfo (_("%P%x: %s: bad IR symbol type %d\n"), name, blhe->type); |
5d3236ee DK |
919 | /* Replace it with new details. */ |
920 | blhe->u.def.section = nsec; | |
921 | blhe->u.def.value = nval; | |
922 | return TRUE; | |
923 | } | |
924 | return plugin_cached_allow_multiple_defs; | |
925 | } |