56854cc5c63bdf92de7263faad8f492970119134
[deliverable/binutils-gdb.git] / gdb / objfiles.c
1 /* GDB routines for manipulating objfiles.
2
3 Copyright (C) 1992-2019 Free Software Foundation, Inc.
4
5 Contributed by Cygnus Support, using pieces from other GDB modules.
6
7 This file is part of GDB.
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21
22 /* This file contains support routines for creating, manipulating, and
23 destroying objfile structures. */
24
25 #include "defs.h"
26 #include "bfd.h" /* Binary File Description */
27 #include "symtab.h"
28 #include "symfile.h"
29 #include "objfiles.h"
30 #include "gdb-stabs.h"
31 #include "target.h"
32 #include "bcache.h"
33 #include "expression.h"
34 #include "parser-defs.h"
35
36 #include <sys/types.h>
37 #include <sys/stat.h>
38 #include <fcntl.h>
39 #include "gdb_obstack.h"
40 #include "hashtab.h"
41
42 #include "breakpoint.h"
43 #include "block.h"
44 #include "dictionary.h"
45 #include "source.h"
46 #include "addrmap.h"
47 #include "arch-utils.h"
48 #include "exec.h"
49 #include "observable.h"
50 #include "complaints.h"
51 #include "psymtab.h"
52 #include "solist.h"
53 #include "gdb_bfd.h"
54 #include "btrace.h"
55 #include "gdbsupport/pathstuff.h"
56
57 #include <algorithm>
58 #include <vector>
59
60 /* Keep a registry of per-objfile data-pointers required by other GDB
61 modules. */
62
63 DEFINE_REGISTRY (objfile, REGISTRY_ACCESS_FIELD)
64
65 /* Externally visible variables that are owned by this module.
66 See declarations in objfile.h for more info. */
67
68 struct objfile_pspace_info
69 {
70 objfile_pspace_info () = default;
71 ~objfile_pspace_info ();
72
73 struct obj_section **sections = nullptr;
74 int num_sections = 0;
75
76 /* Nonzero if object files have been added since the section map
77 was last updated. */
78 int new_objfiles_available = 0;
79
80 /* Nonzero if the section map MUST be updated before use. */
81 int section_map_dirty = 0;
82
83 /* Nonzero if section map updates should be inhibited if possible. */
84 int inhibit_updates = 0;
85 };
86
87 /* Per-program-space data key. */
88 static const struct program_space_key<objfile_pspace_info>
89 objfiles_pspace_data;
90
91 objfile_pspace_info::~objfile_pspace_info ()
92 {
93 xfree (sections);
94 }
95
96 /* Get the current svr4 data. If none is found yet, add it now. This
97 function always returns a valid object. */
98
99 static struct objfile_pspace_info *
100 get_objfile_pspace_data (struct program_space *pspace)
101 {
102 struct objfile_pspace_info *info;
103
104 info = objfiles_pspace_data.get (pspace);
105 if (info == NULL)
106 info = objfiles_pspace_data.emplace (pspace);
107
108 return info;
109 }
110
111 \f
112
113 /* Per-BFD data key. */
114
115 static const struct bfd_key<objfile_per_bfd_storage> objfiles_bfd_data;
116
117 objfile_per_bfd_storage::~objfile_per_bfd_storage ()
118 {
119 }
120
121 /* Create the per-BFD storage object for OBJFILE. If ABFD is not
122 NULL, and it already has a per-BFD storage object, use that.
123 Otherwise, allocate a new per-BFD storage object. Note that it is
124 not safe to call this multiple times for a given OBJFILE -- it can
125 only be called when allocating or re-initializing OBJFILE. */
126
127 static struct objfile_per_bfd_storage *
128 get_objfile_bfd_data (struct objfile *objfile, struct bfd *abfd)
129 {
130 struct objfile_per_bfd_storage *storage = NULL;
131
132 if (abfd != NULL)
133 storage = objfiles_bfd_data.get (abfd);
134
135 if (storage == NULL)
136 {
137 storage = new objfile_per_bfd_storage;
138 /* If the object requires gdb to do relocations, we simply fall
139 back to not sharing data across users. These cases are rare
140 enough that this seems reasonable. */
141 if (abfd != NULL && !gdb_bfd_requires_relocations (abfd))
142 objfiles_bfd_data.set (abfd, storage);
143
144 /* Look up the gdbarch associated with the BFD. */
145 if (abfd != NULL)
146 storage->gdbarch = gdbarch_from_bfd (abfd);
147 }
148
149 return storage;
150 }
151
152 /* See objfiles.h. */
153
154 void
155 set_objfile_per_bfd (struct objfile *objfile)
156 {
157 objfile->per_bfd = get_objfile_bfd_data (objfile, objfile->obfd);
158 }
159
160 /* Set the objfile's per-BFD notion of the "main" name and
161 language. */
162
163 void
164 set_objfile_main_name (struct objfile *objfile,
165 const char *name, enum language lang)
166 {
167 if (objfile->per_bfd->name_of_main == NULL
168 || strcmp (objfile->per_bfd->name_of_main, name) != 0)
169 objfile->per_bfd->name_of_main
170 = obstack_strdup (&objfile->per_bfd->storage_obstack, name);
171 objfile->per_bfd->language_of_main = lang;
172 }
173
174 /* Helper structure to map blocks to static link properties in hash tables. */
175
176 struct static_link_htab_entry
177 {
178 const struct block *block;
179 const struct dynamic_prop *static_link;
180 };
181
182 /* Return a hash code for struct static_link_htab_entry *P. */
183
184 static hashval_t
185 static_link_htab_entry_hash (const void *p)
186 {
187 const struct static_link_htab_entry *e
188 = (const struct static_link_htab_entry *) p;
189
190 return htab_hash_pointer (e->block);
191 }
192
193 /* Return whether P1 an P2 (pointers to struct static_link_htab_entry) are
194 mappings for the same block. */
195
196 static int
197 static_link_htab_entry_eq (const void *p1, const void *p2)
198 {
199 const struct static_link_htab_entry *e1
200 = (const struct static_link_htab_entry *) p1;
201 const struct static_link_htab_entry *e2
202 = (const struct static_link_htab_entry *) p2;
203
204 return e1->block == e2->block;
205 }
206
207 /* Register STATIC_LINK as the static link for BLOCK, which is part of OBJFILE.
208 Must not be called more than once for each BLOCK. */
209
210 void
211 objfile_register_static_link (struct objfile *objfile,
212 const struct block *block,
213 const struct dynamic_prop *static_link)
214 {
215 void **slot;
216 struct static_link_htab_entry lookup_entry;
217 struct static_link_htab_entry *entry;
218
219 if (objfile->static_links == NULL)
220 objfile->static_links.reset (htab_create_alloc
221 (1, &static_link_htab_entry_hash, static_link_htab_entry_eq, NULL,
222 xcalloc, xfree));
223
224 /* Create a slot for the mapping, make sure it's the first mapping for this
225 block and then create the mapping itself. */
226 lookup_entry.block = block;
227 slot = htab_find_slot (objfile->static_links.get (), &lookup_entry, INSERT);
228 gdb_assert (*slot == NULL);
229
230 entry = XOBNEW (&objfile->objfile_obstack, static_link_htab_entry);
231 entry->block = block;
232 entry->static_link = static_link;
233 *slot = (void *) entry;
234 }
235
236 /* Look for a static link for BLOCK, which is part of OBJFILE. Return NULL if
237 none was found. */
238
239 const struct dynamic_prop *
240 objfile_lookup_static_link (struct objfile *objfile,
241 const struct block *block)
242 {
243 struct static_link_htab_entry *entry;
244 struct static_link_htab_entry lookup_entry;
245
246 if (objfile->static_links == NULL)
247 return NULL;
248 lookup_entry.block = block;
249 entry = ((struct static_link_htab_entry *)
250 htab_find (objfile->static_links.get (), &lookup_entry));
251 if (entry == NULL)
252 return NULL;
253
254 gdb_assert (entry->block == block);
255 return entry->static_link;
256 }
257
258 \f
259
260 /* Called via bfd_map_over_sections to build up the section table that
261 the objfile references. The objfile contains pointers to the start
262 of the table (objfile->sections) and to the first location after
263 the end of the table (objfile->sections_end). */
264
265 static void
266 add_to_objfile_sections_full (struct bfd *abfd, struct bfd_section *asect,
267 struct objfile *objfile, int force)
268 {
269 struct obj_section *section;
270
271 if (!force)
272 {
273 flagword aflag;
274
275 aflag = bfd_section_flags (asect);
276 if (!(aflag & SEC_ALLOC))
277 return;
278 }
279
280 section = &objfile->sections[gdb_bfd_section_index (abfd, asect)];
281 section->objfile = objfile;
282 section->the_bfd_section = asect;
283 section->ovly_mapped = 0;
284 }
285
286 static void
287 add_to_objfile_sections (struct bfd *abfd, struct bfd_section *asect,
288 void *objfilep)
289 {
290 add_to_objfile_sections_full (abfd, asect, (struct objfile *) objfilep, 0);
291 }
292
293 /* Builds a section table for OBJFILE.
294
295 Note that the OFFSET and OVLY_MAPPED in each table entry are
296 initialized to zero. */
297
298 void
299 build_objfile_section_table (struct objfile *objfile)
300 {
301 int count = gdb_bfd_count_sections (objfile->obfd);
302
303 objfile->sections = OBSTACK_CALLOC (&objfile->objfile_obstack,
304 count,
305 struct obj_section);
306 objfile->sections_end = (objfile->sections + count);
307 bfd_map_over_sections (objfile->obfd,
308 add_to_objfile_sections, (void *) objfile);
309
310 /* See gdb_bfd_section_index. */
311 add_to_objfile_sections_full (objfile->obfd, bfd_com_section_ptr, objfile, 1);
312 add_to_objfile_sections_full (objfile->obfd, bfd_und_section_ptr, objfile, 1);
313 add_to_objfile_sections_full (objfile->obfd, bfd_abs_section_ptr, objfile, 1);
314 add_to_objfile_sections_full (objfile->obfd, bfd_ind_section_ptr, objfile, 1);
315 }
316
317 /* Given a pointer to an initialized bfd (ABFD) and some flag bits,
318 initialize the new objfile as best we can and link it into the list
319 of all known objfiles.
320
321 NAME should contain original non-canonicalized filename or other
322 identifier as entered by user. If there is no better source use
323 bfd_get_filename (ABFD). NAME may be NULL only if ABFD is NULL.
324 NAME content is copied into returned objfile.
325
326 The FLAGS word contains various bits (OBJF_*) that can be taken as
327 requests for specific operations. Other bits like OBJF_SHARED are
328 simply copied through to the new objfile flags member. */
329
330 objfile::objfile (bfd *abfd, const char *name, objfile_flags flags_)
331 : flags (flags_),
332 pspace (current_program_space),
333 partial_symtabs (new psymtab_storage ()),
334 obfd (abfd)
335 {
336 const char *expanded_name;
337
338 /* We could use obstack_specify_allocation here instead, but
339 gdb_obstack.h specifies the alloc/dealloc functions. */
340 obstack_init (&objfile_obstack);
341
342 objfile_alloc_data (this);
343
344 gdb::unique_xmalloc_ptr<char> name_holder;
345 if (name == NULL)
346 {
347 gdb_assert (abfd == NULL);
348 gdb_assert ((flags & OBJF_NOT_FILENAME) != 0);
349 expanded_name = "<<anonymous objfile>>";
350 }
351 else if ((flags & OBJF_NOT_FILENAME) != 0
352 || is_target_filename (name))
353 expanded_name = name;
354 else
355 {
356 name_holder = gdb_abspath (name);
357 expanded_name = name_holder.get ();
358 }
359 original_name = obstack_strdup (&objfile_obstack, expanded_name);
360
361 /* Update the per-objfile information that comes from the bfd, ensuring
362 that any data that is reference is saved in the per-objfile data
363 region. */
364
365 gdb_bfd_ref (abfd);
366 if (abfd != NULL)
367 {
368 mtime = bfd_get_mtime (abfd);
369
370 /* Build section table. */
371 build_objfile_section_table (this);
372 }
373
374 per_bfd = get_objfile_bfd_data (this, abfd);
375 }
376
377 /* Retrieve the gdbarch associated with OBJFILE. */
378
379 struct gdbarch *
380 get_objfile_arch (const struct objfile *objfile)
381 {
382 return objfile->per_bfd->gdbarch;
383 }
384
385 /* If there is a valid and known entry point, function fills *ENTRY_P with it
386 and returns non-zero; otherwise it returns zero. */
387
388 int
389 entry_point_address_query (CORE_ADDR *entry_p)
390 {
391 if (symfile_objfile == NULL || !symfile_objfile->per_bfd->ei.entry_point_p)
392 return 0;
393
394 *entry_p = (symfile_objfile->per_bfd->ei.entry_point
395 + ANOFFSET (symfile_objfile->section_offsets,
396 symfile_objfile->per_bfd->ei.the_bfd_section_index));
397
398 return 1;
399 }
400
401 /* Get current entry point address. Call error if it is not known. */
402
403 CORE_ADDR
404 entry_point_address (void)
405 {
406 CORE_ADDR retval;
407
408 if (!entry_point_address_query (&retval))
409 error (_("Entry point address is not known."));
410
411 return retval;
412 }
413
414 separate_debug_iterator &
415 separate_debug_iterator::operator++ ()
416 {
417 gdb_assert (m_objfile != nullptr);
418
419 struct objfile *res;
420
421 /* If any, return the first child. */
422 res = m_objfile->separate_debug_objfile;
423 if (res != nullptr)
424 {
425 m_objfile = res;
426 return *this;
427 }
428
429 /* Common case where there is no separate debug objfile. */
430 if (m_objfile == m_parent)
431 {
432 m_objfile = nullptr;
433 return *this;
434 }
435
436 /* Return the brother if any. Note that we don't iterate on brothers of
437 the parents. */
438 res = m_objfile->separate_debug_objfile_link;
439 if (res != nullptr)
440 {
441 m_objfile = res;
442 return *this;
443 }
444
445 for (res = m_objfile->separate_debug_objfile_backlink;
446 res != m_parent;
447 res = res->separate_debug_objfile_backlink)
448 {
449 gdb_assert (res != nullptr);
450 if (res->separate_debug_objfile_link != nullptr)
451 {
452 m_objfile = res->separate_debug_objfile_link;
453 return *this;
454 }
455 }
456 m_objfile = nullptr;
457 return *this;
458 }
459
460 /* Add OBJFILE as a separate debug objfile of PARENT. */
461
462 static void
463 add_separate_debug_objfile (struct objfile *objfile, struct objfile *parent)
464 {
465 gdb_assert (objfile && parent);
466
467 /* Must not be already in a list. */
468 gdb_assert (objfile->separate_debug_objfile_backlink == NULL);
469 gdb_assert (objfile->separate_debug_objfile_link == NULL);
470 gdb_assert (objfile->separate_debug_objfile == NULL);
471 gdb_assert (parent->separate_debug_objfile_backlink == NULL);
472 gdb_assert (parent->separate_debug_objfile_link == NULL);
473
474 objfile->separate_debug_objfile_backlink = parent;
475 objfile->separate_debug_objfile_link = parent->separate_debug_objfile;
476 parent->separate_debug_objfile = objfile;
477 }
478
479 /* See objfiles.h. */
480
481 objfile *
482 objfile::make (bfd *bfd_, const char *name_, objfile_flags flags_,
483 objfile *parent)
484 {
485 objfile *result = new objfile (bfd_, name_, flags_);
486 if (parent != nullptr)
487 add_separate_debug_objfile (result, parent);
488
489 current_program_space->add_objfile (result, parent);
490
491 /* Rebuild section map next time we need it. */
492 get_objfile_pspace_data (current_program_space)->new_objfiles_available = 1;
493
494 return result;
495 }
496
497 /* See objfiles.h. */
498
499 void
500 objfile::unlink ()
501 {
502 current_program_space->remove_objfile (this);
503 delete this;
504 }
505
506 /* Free all separate debug objfile of OBJFILE, but don't free OBJFILE
507 itself. */
508
509 void
510 free_objfile_separate_debug (struct objfile *objfile)
511 {
512 struct objfile *child;
513
514 for (child = objfile->separate_debug_objfile; child;)
515 {
516 struct objfile *next_child = child->separate_debug_objfile_link;
517 child->unlink ();
518 child = next_child;
519 }
520 }
521
522 /* Destroy an objfile and all the symtabs and psymtabs under it. */
523
524 objfile::~objfile ()
525 {
526 /* First notify observers that this objfile is about to be freed. */
527 gdb::observers::free_objfile.notify (this);
528
529 /* Free all separate debug objfiles. */
530 free_objfile_separate_debug (this);
531
532 if (separate_debug_objfile_backlink)
533 {
534 /* We freed the separate debug file, make sure the base objfile
535 doesn't reference it. */
536 struct objfile *child;
537
538 child = separate_debug_objfile_backlink->separate_debug_objfile;
539
540 if (child == this)
541 {
542 /* THIS is the first child. */
543 separate_debug_objfile_backlink->separate_debug_objfile =
544 separate_debug_objfile_link;
545 }
546 else
547 {
548 /* Find THIS in the list. */
549 while (1)
550 {
551 if (child->separate_debug_objfile_link == this)
552 {
553 child->separate_debug_objfile_link =
554 separate_debug_objfile_link;
555 break;
556 }
557 child = child->separate_debug_objfile_link;
558 gdb_assert (child);
559 }
560 }
561 }
562
563 /* Remove any references to this objfile in the global value
564 lists. */
565 preserve_values (this);
566
567 /* It still may reference data modules have associated with the objfile and
568 the symbol file data. */
569 forget_cached_source_info_for_objfile (this);
570
571 breakpoint_free_objfile (this);
572 btrace_free_objfile (this);
573
574 /* First do any symbol file specific actions required when we are
575 finished with a particular symbol file. Note that if the objfile
576 is using reusable symbol information (via mmalloc) then each of
577 these routines is responsible for doing the correct thing, either
578 freeing things which are valid only during this particular gdb
579 execution, or leaving them to be reused during the next one. */
580
581 if (sf != NULL)
582 (*sf->sym_finish) (this);
583
584 /* Discard any data modules have associated with the objfile. The function
585 still may reference obfd. */
586 objfile_free_data (this);
587
588 if (obfd)
589 gdb_bfd_unref (obfd);
590 else
591 delete per_bfd;
592
593 /* Before the symbol table code was redone to make it easier to
594 selectively load and remove information particular to a specific
595 linkage unit, gdb used to do these things whenever the monolithic
596 symbol table was blown away. How much still needs to be done
597 is unknown, but we play it safe for now and keep each action until
598 it is shown to be no longer needed. */
599
600 /* Not all our callers call clear_symtab_users (objfile_purge_solibs,
601 for example), so we need to call this here. */
602 clear_pc_function_cache ();
603
604 /* Check to see if the current_source_symtab belongs to this objfile,
605 and if so, call clear_current_source_symtab_and_line. */
606
607 {
608 struct symtab_and_line cursal = get_current_source_symtab_and_line ();
609
610 if (cursal.symtab && SYMTAB_OBJFILE (cursal.symtab) == this)
611 clear_current_source_symtab_and_line ();
612 }
613
614 /* Free the obstacks for non-reusable objfiles. */
615 obstack_free (&objfile_obstack, 0);
616
617 /* Rebuild section map next time we need it. */
618 get_objfile_pspace_data (pspace)->section_map_dirty = 1;
619 }
620
621 \f
622 /* A helper function for objfile_relocate1 that relocates a single
623 symbol. */
624
625 static void
626 relocate_one_symbol (struct symbol *sym, struct objfile *objfile,
627 struct section_offsets *delta)
628 {
629 fixup_symbol_section (sym, objfile);
630
631 /* The RS6000 code from which this was taken skipped
632 any symbols in STRUCT_DOMAIN or UNDEF_DOMAIN.
633 But I'm leaving out that test, on the theory that
634 they can't possibly pass the tests below. */
635 if ((SYMBOL_CLASS (sym) == LOC_LABEL
636 || SYMBOL_CLASS (sym) == LOC_STATIC)
637 && SYMBOL_SECTION (sym) >= 0)
638 {
639 SET_SYMBOL_VALUE_ADDRESS (sym,
640 SYMBOL_VALUE_ADDRESS (sym)
641 + ANOFFSET (delta, SYMBOL_SECTION (sym)));
642 }
643 }
644
645 /* Relocate OBJFILE to NEW_OFFSETS. There should be OBJFILE->NUM_SECTIONS
646 entries in new_offsets. SEPARATE_DEBUG_OBJFILE is not touched here.
647 Return non-zero iff any change happened. */
648
649 static int
650 objfile_relocate1 (struct objfile *objfile,
651 const struct section_offsets *new_offsets)
652 {
653 struct section_offsets *delta =
654 ((struct section_offsets *)
655 alloca (SIZEOF_N_SECTION_OFFSETS (objfile->num_sections)));
656
657 int something_changed = 0;
658
659 for (int i = 0; i < objfile->num_sections; ++i)
660 {
661 delta->offsets[i] =
662 ANOFFSET (new_offsets, i) - ANOFFSET (objfile->section_offsets, i);
663 if (ANOFFSET (delta, i) != 0)
664 something_changed = 1;
665 }
666 if (!something_changed)
667 return 0;
668
669 /* OK, get all the symtabs. */
670 {
671 for (compunit_symtab *cust : objfile->compunits ())
672 {
673 for (symtab *s : compunit_filetabs (cust))
674 {
675 struct linetable *l;
676
677 /* First the line table. */
678 l = SYMTAB_LINETABLE (s);
679 if (l)
680 {
681 for (int i = 0; i < l->nitems; ++i)
682 l->item[i].pc += ANOFFSET (delta,
683 COMPUNIT_BLOCK_LINE_SECTION
684 (cust));
685 }
686 }
687 }
688
689 for (compunit_symtab *cust : objfile->compunits ())
690 {
691 const struct blockvector *bv = COMPUNIT_BLOCKVECTOR (cust);
692 int block_line_section = COMPUNIT_BLOCK_LINE_SECTION (cust);
693
694 if (BLOCKVECTOR_MAP (bv))
695 addrmap_relocate (BLOCKVECTOR_MAP (bv),
696 ANOFFSET (delta, block_line_section));
697
698 for (int i = 0; i < BLOCKVECTOR_NBLOCKS (bv); ++i)
699 {
700 struct block *b;
701 struct symbol *sym;
702 struct mdict_iterator miter;
703
704 b = BLOCKVECTOR_BLOCK (bv, i);
705 BLOCK_START (b) += ANOFFSET (delta, block_line_section);
706 BLOCK_END (b) += ANOFFSET (delta, block_line_section);
707
708 if (BLOCK_RANGES (b) != nullptr)
709 for (int j = 0; j < BLOCK_NRANGES (b); j++)
710 {
711 BLOCK_RANGE_START (b, j)
712 += ANOFFSET (delta, block_line_section);
713 BLOCK_RANGE_END (b, j) += ANOFFSET (delta,
714 block_line_section);
715 }
716
717 /* We only want to iterate over the local symbols, not any
718 symbols in included symtabs. */
719 ALL_DICT_SYMBOLS (BLOCK_MULTIDICT (b), miter, sym)
720 {
721 relocate_one_symbol (sym, objfile, delta);
722 }
723 }
724 }
725 }
726
727 /* This stores relocated addresses and so must be cleared. This
728 will cause it to be recreated on demand. */
729 objfile->psymbol_map.clear ();
730
731 /* Relocate isolated symbols. */
732 {
733 struct symbol *iter;
734
735 for (iter = objfile->template_symbols; iter; iter = iter->hash_next)
736 relocate_one_symbol (iter, objfile, delta);
737 }
738
739 {
740 int i;
741
742 for (i = 0; i < objfile->num_sections; ++i)
743 (objfile->section_offsets)->offsets[i] = ANOFFSET (new_offsets, i);
744 }
745
746 /* Rebuild section map next time we need it. */
747 get_objfile_pspace_data (objfile->pspace)->section_map_dirty = 1;
748
749 /* Update the table in exec_ops, used to read memory. */
750 struct obj_section *s;
751 ALL_OBJFILE_OSECTIONS (objfile, s)
752 {
753 int idx = s - objfile->sections;
754
755 exec_set_section_address (bfd_get_filename (objfile->obfd), idx,
756 obj_section_addr (s));
757 }
758
759 /* Data changed. */
760 return 1;
761 }
762
763 /* Relocate OBJFILE to NEW_OFFSETS. There should be OBJFILE->NUM_SECTIONS
764 entries in new_offsets. Process also OBJFILE's SEPARATE_DEBUG_OBJFILEs.
765
766 The number and ordering of sections does differ between the two objfiles.
767 Only their names match. Also the file offsets will differ (objfile being
768 possibly prelinked but separate_debug_objfile is probably not prelinked) but
769 the in-memory absolute address as specified by NEW_OFFSETS must match both
770 files. */
771
772 void
773 objfile_relocate (struct objfile *objfile,
774 const struct section_offsets *new_offsets)
775 {
776 int changed = 0;
777
778 changed |= objfile_relocate1 (objfile, new_offsets);
779
780 for (::objfile *debug_objfile : objfile->separate_debug_objfiles ())
781 {
782 if (debug_objfile == objfile)
783 continue;
784
785 section_addr_info objfile_addrs
786 = build_section_addr_info_from_objfile (objfile);
787
788 /* Here OBJFILE_ADDRS contain the correct absolute addresses, the
789 relative ones must be already created according to debug_objfile. */
790
791 addr_info_make_relative (&objfile_addrs, debug_objfile->obfd);
792
793 gdb_assert (debug_objfile->num_sections
794 == gdb_bfd_count_sections (debug_objfile->obfd));
795 std::vector<struct section_offsets>
796 new_debug_offsets (SIZEOF_N_SECTION_OFFSETS (debug_objfile->num_sections));
797 relative_addr_info_to_section_offsets (new_debug_offsets.data (),
798 debug_objfile->num_sections,
799 objfile_addrs);
800
801 changed |= objfile_relocate1 (debug_objfile, new_debug_offsets.data ());
802 }
803
804 /* Relocate breakpoints as necessary, after things are relocated. */
805 if (changed)
806 breakpoint_re_set ();
807 }
808
809 /* Rebase (add to the offsets) OBJFILE by SLIDE. SEPARATE_DEBUG_OBJFILE is
810 not touched here.
811 Return non-zero iff any change happened. */
812
813 static int
814 objfile_rebase1 (struct objfile *objfile, CORE_ADDR slide)
815 {
816 struct section_offsets *new_offsets =
817 ((struct section_offsets *)
818 alloca (SIZEOF_N_SECTION_OFFSETS (objfile->num_sections)));
819 int i;
820
821 for (i = 0; i < objfile->num_sections; ++i)
822 new_offsets->offsets[i] = slide;
823
824 return objfile_relocate1 (objfile, new_offsets);
825 }
826
827 /* Rebase (add to the offsets) OBJFILE by SLIDE. Process also OBJFILE's
828 SEPARATE_DEBUG_OBJFILEs. */
829
830 void
831 objfile_rebase (struct objfile *objfile, CORE_ADDR slide)
832 {
833 int changed = 0;
834
835 for (::objfile *debug_objfile : objfile->separate_debug_objfiles ())
836 changed |= objfile_rebase1 (debug_objfile, slide);
837
838 /* Relocate breakpoints as necessary, after things are relocated. */
839 if (changed)
840 breakpoint_re_set ();
841 }
842 \f
843 /* Return non-zero if OBJFILE has partial symbols. */
844
845 int
846 objfile_has_partial_symbols (struct objfile *objfile)
847 {
848 if (!objfile->sf)
849 return 0;
850
851 /* If we have not read psymbols, but we have a function capable of reading
852 them, then that is an indication that they are in fact available. Without
853 this function the symbols may have been already read in but they also may
854 not be present in this objfile. */
855 if ((objfile->flags & OBJF_PSYMTABS_READ) == 0
856 && objfile->sf->sym_read_psymbols != NULL)
857 return 1;
858
859 return objfile->sf->qf->has_symbols (objfile);
860 }
861
862 /* Return non-zero if OBJFILE has full symbols. */
863
864 int
865 objfile_has_full_symbols (struct objfile *objfile)
866 {
867 return objfile->compunit_symtabs != NULL;
868 }
869
870 /* Return non-zero if OBJFILE has full or partial symbols, either directly
871 or through a separate debug file. */
872
873 int
874 objfile_has_symbols (struct objfile *objfile)
875 {
876 for (::objfile *o : objfile->separate_debug_objfiles ())
877 if (objfile_has_partial_symbols (o) || objfile_has_full_symbols (o))
878 return 1;
879 return 0;
880 }
881
882
883 /* Many places in gdb want to test just to see if we have any partial
884 symbols available. This function returns zero if none are currently
885 available, nonzero otherwise. */
886
887 int
888 have_partial_symbols (void)
889 {
890 for (objfile *ofp : current_program_space->objfiles ())
891 {
892 if (objfile_has_partial_symbols (ofp))
893 return 1;
894 }
895 return 0;
896 }
897
898 /* Many places in gdb want to test just to see if we have any full
899 symbols available. This function returns zero if none are currently
900 available, nonzero otherwise. */
901
902 int
903 have_full_symbols (void)
904 {
905 for (objfile *ofp : current_program_space->objfiles ())
906 {
907 if (objfile_has_full_symbols (ofp))
908 return 1;
909 }
910 return 0;
911 }
912
913
914 /* This operations deletes all objfile entries that represent solibs that
915 weren't explicitly loaded by the user, via e.g., the add-symbol-file
916 command. */
917
918 void
919 objfile_purge_solibs (void)
920 {
921 for (objfile *objf : current_program_space->objfiles_safe ())
922 {
923 /* We assume that the solib package has been purged already, or will
924 be soon. */
925
926 if (!(objf->flags & OBJF_USERLOADED) && (objf->flags & OBJF_SHARED))
927 objf->unlink ();
928 }
929 }
930
931
932 /* Many places in gdb want to test just to see if we have any minimal
933 symbols available. This function returns zero if none are currently
934 available, nonzero otherwise. */
935
936 int
937 have_minimal_symbols (void)
938 {
939 for (objfile *ofp : current_program_space->objfiles ())
940 {
941 if (ofp->per_bfd->minimal_symbol_count > 0)
942 {
943 return 1;
944 }
945 }
946 return 0;
947 }
948
949 /* Qsort comparison function. */
950
951 static bool
952 sort_cmp (const struct obj_section *sect1, const obj_section *sect2)
953 {
954 const CORE_ADDR sect1_addr = obj_section_addr (sect1);
955 const CORE_ADDR sect2_addr = obj_section_addr (sect2);
956
957 if (sect1_addr < sect2_addr)
958 return true;
959 else if (sect1_addr > sect2_addr)
960 return false;
961 else
962 {
963 /* Sections are at the same address. This could happen if
964 A) we have an objfile and a separate debuginfo.
965 B) we are confused, and have added sections without proper relocation,
966 or something like that. */
967
968 const struct objfile *const objfile1 = sect1->objfile;
969 const struct objfile *const objfile2 = sect2->objfile;
970
971 if (objfile1->separate_debug_objfile == objfile2
972 || objfile2->separate_debug_objfile == objfile1)
973 {
974 /* Case A. The ordering doesn't matter: separate debuginfo files
975 will be filtered out later. */
976
977 return false;
978 }
979
980 /* Case B. Maintain stable sort order, so bugs in GDB are easier to
981 triage. This section could be slow (since we iterate over all
982 objfiles in each call to sort_cmp), but this shouldn't happen
983 very often (GDB is already in a confused state; one hopes this
984 doesn't happen at all). If you discover that significant time is
985 spent in the loops below, do 'set complaints 100' and examine the
986 resulting complaints. */
987 if (objfile1 == objfile2)
988 {
989 /* Both sections came from the same objfile. We are really
990 confused. Sort on sequence order of sections within the
991 objfile. The order of checks is important here, if we find a
992 match on SECT2 first then either SECT2 is before SECT1, or,
993 SECT2 == SECT1, in both cases we should return false. The
994 second case shouldn't occur during normal use, but std::sort
995 does check that '!(a < a)' when compiled in debug mode. */
996
997 const struct obj_section *osect;
998
999 ALL_OBJFILE_OSECTIONS (objfile1, osect)
1000 if (osect == sect2)
1001 return false;
1002 else if (osect == sect1)
1003 return true;
1004
1005 /* We should have found one of the sections before getting here. */
1006 gdb_assert_not_reached ("section not found");
1007 }
1008 else
1009 {
1010 /* Sort on sequence number of the objfile in the chain. */
1011
1012 for (objfile *objfile : current_program_space->objfiles ())
1013 if (objfile == objfile1)
1014 return true;
1015 else if (objfile == objfile2)
1016 return false;
1017
1018 /* We should have found one of the objfiles before getting here. */
1019 gdb_assert_not_reached ("objfile not found");
1020 }
1021 }
1022
1023 /* Unreachable. */
1024 gdb_assert_not_reached ("unexpected code path");
1025 return false;
1026 }
1027
1028 /* Select "better" obj_section to keep. We prefer the one that came from
1029 the real object, rather than the one from separate debuginfo.
1030 Most of the time the two sections are exactly identical, but with
1031 prelinking the .rel.dyn section in the real object may have different
1032 size. */
1033
1034 static struct obj_section *
1035 preferred_obj_section (struct obj_section *a, struct obj_section *b)
1036 {
1037 gdb_assert (obj_section_addr (a) == obj_section_addr (b));
1038 gdb_assert ((a->objfile->separate_debug_objfile == b->objfile)
1039 || (b->objfile->separate_debug_objfile == a->objfile));
1040 gdb_assert ((a->objfile->separate_debug_objfile_backlink == b->objfile)
1041 || (b->objfile->separate_debug_objfile_backlink == a->objfile));
1042
1043 if (a->objfile->separate_debug_objfile != NULL)
1044 return a;
1045 return b;
1046 }
1047
1048 /* Return 1 if SECTION should be inserted into the section map.
1049 We want to insert only non-overlay and non-TLS section. */
1050
1051 static int
1052 insert_section_p (const struct bfd *abfd,
1053 const struct bfd_section *section)
1054 {
1055 const bfd_vma lma = bfd_section_lma (section);
1056
1057 if (overlay_debugging && lma != 0 && lma != bfd_section_vma (section)
1058 && (bfd_get_file_flags (abfd) & BFD_IN_MEMORY) == 0)
1059 /* This is an overlay section. IN_MEMORY check is needed to avoid
1060 discarding sections from the "system supplied DSO" (aka vdso)
1061 on some Linux systems (e.g. Fedora 11). */
1062 return 0;
1063 if ((bfd_section_flags (section) & SEC_THREAD_LOCAL) != 0)
1064 /* This is a TLS section. */
1065 return 0;
1066
1067 return 1;
1068 }
1069
1070 /* Filter out overlapping sections where one section came from the real
1071 objfile, and the other from a separate debuginfo file.
1072 Return the size of table after redundant sections have been eliminated. */
1073
1074 static int
1075 filter_debuginfo_sections (struct obj_section **map, int map_size)
1076 {
1077 int i, j;
1078
1079 for (i = 0, j = 0; i < map_size - 1; i++)
1080 {
1081 struct obj_section *const sect1 = map[i];
1082 struct obj_section *const sect2 = map[i + 1];
1083 const struct objfile *const objfile1 = sect1->objfile;
1084 const struct objfile *const objfile2 = sect2->objfile;
1085 const CORE_ADDR sect1_addr = obj_section_addr (sect1);
1086 const CORE_ADDR sect2_addr = obj_section_addr (sect2);
1087
1088 if (sect1_addr == sect2_addr
1089 && (objfile1->separate_debug_objfile == objfile2
1090 || objfile2->separate_debug_objfile == objfile1))
1091 {
1092 map[j++] = preferred_obj_section (sect1, sect2);
1093 ++i;
1094 }
1095 else
1096 map[j++] = sect1;
1097 }
1098
1099 if (i < map_size)
1100 {
1101 gdb_assert (i == map_size - 1);
1102 map[j++] = map[i];
1103 }
1104
1105 /* The map should not have shrunk to less than half the original size. */
1106 gdb_assert (map_size / 2 <= j);
1107
1108 return j;
1109 }
1110
1111 /* Filter out overlapping sections, issuing a warning if any are found.
1112 Overlapping sections could really be overlay sections which we didn't
1113 classify as such in insert_section_p, or we could be dealing with a
1114 corrupt binary. */
1115
1116 static int
1117 filter_overlapping_sections (struct obj_section **map, int map_size)
1118 {
1119 int i, j;
1120
1121 for (i = 0, j = 0; i < map_size - 1; )
1122 {
1123 int k;
1124
1125 map[j++] = map[i];
1126 for (k = i + 1; k < map_size; k++)
1127 {
1128 struct obj_section *const sect1 = map[i];
1129 struct obj_section *const sect2 = map[k];
1130 const CORE_ADDR sect1_addr = obj_section_addr (sect1);
1131 const CORE_ADDR sect2_addr = obj_section_addr (sect2);
1132 const CORE_ADDR sect1_endaddr = obj_section_endaddr (sect1);
1133
1134 gdb_assert (sect1_addr <= sect2_addr);
1135
1136 if (sect1_endaddr <= sect2_addr)
1137 break;
1138 else
1139 {
1140 /* We have an overlap. Report it. */
1141
1142 struct objfile *const objf1 = sect1->objfile;
1143 struct objfile *const objf2 = sect2->objfile;
1144
1145 const struct bfd_section *const bfds1 = sect1->the_bfd_section;
1146 const struct bfd_section *const bfds2 = sect2->the_bfd_section;
1147
1148 const CORE_ADDR sect2_endaddr = obj_section_endaddr (sect2);
1149
1150 struct gdbarch *const gdbarch = get_objfile_arch (objf1);
1151
1152 complaint (_("unexpected overlap between:\n"
1153 " (A) section `%s' from `%s' [%s, %s)\n"
1154 " (B) section `%s' from `%s' [%s, %s).\n"
1155 "Will ignore section B"),
1156 bfd_section_name (bfds1), objfile_name (objf1),
1157 paddress (gdbarch, sect1_addr),
1158 paddress (gdbarch, sect1_endaddr),
1159 bfd_section_name (bfds2), objfile_name (objf2),
1160 paddress (gdbarch, sect2_addr),
1161 paddress (gdbarch, sect2_endaddr));
1162 }
1163 }
1164 i = k;
1165 }
1166
1167 if (i < map_size)
1168 {
1169 gdb_assert (i == map_size - 1);
1170 map[j++] = map[i];
1171 }
1172
1173 return j;
1174 }
1175
1176
1177 /* Update PMAP, PMAP_SIZE with sections from all objfiles, excluding any
1178 TLS, overlay and overlapping sections. */
1179
1180 static void
1181 update_section_map (struct program_space *pspace,
1182 struct obj_section ***pmap, int *pmap_size)
1183 {
1184 struct objfile_pspace_info *pspace_info;
1185 int alloc_size, map_size, i;
1186 struct obj_section *s, **map;
1187
1188 pspace_info = get_objfile_pspace_data (pspace);
1189 gdb_assert (pspace_info->section_map_dirty != 0
1190 || pspace_info->new_objfiles_available != 0);
1191
1192 map = *pmap;
1193 xfree (map);
1194
1195 alloc_size = 0;
1196 for (objfile *objfile : pspace->objfiles ())
1197 ALL_OBJFILE_OSECTIONS (objfile, s)
1198 if (insert_section_p (objfile->obfd, s->the_bfd_section))
1199 alloc_size += 1;
1200
1201 /* This happens on detach/attach (e.g. in gdb.base/attach.exp). */
1202 if (alloc_size == 0)
1203 {
1204 *pmap = NULL;
1205 *pmap_size = 0;
1206 return;
1207 }
1208
1209 map = XNEWVEC (struct obj_section *, alloc_size);
1210
1211 i = 0;
1212 for (objfile *objfile : pspace->objfiles ())
1213 ALL_OBJFILE_OSECTIONS (objfile, s)
1214 if (insert_section_p (objfile->obfd, s->the_bfd_section))
1215 map[i++] = s;
1216
1217 std::sort (map, map + alloc_size, sort_cmp);
1218 map_size = filter_debuginfo_sections(map, alloc_size);
1219 map_size = filter_overlapping_sections(map, map_size);
1220
1221 if (map_size < alloc_size)
1222 /* Some sections were eliminated. Trim excess space. */
1223 map = XRESIZEVEC (struct obj_section *, map, map_size);
1224 else
1225 gdb_assert (alloc_size == map_size);
1226
1227 *pmap = map;
1228 *pmap_size = map_size;
1229 }
1230
1231 /* Bsearch comparison function. */
1232
1233 static int
1234 bsearch_cmp (const void *key, const void *elt)
1235 {
1236 const CORE_ADDR pc = *(CORE_ADDR *) key;
1237 const struct obj_section *section = *(const struct obj_section **) elt;
1238
1239 if (pc < obj_section_addr (section))
1240 return -1;
1241 if (pc < obj_section_endaddr (section))
1242 return 0;
1243 return 1;
1244 }
1245
1246 /* Returns a section whose range includes PC or NULL if none found. */
1247
1248 struct obj_section *
1249 find_pc_section (CORE_ADDR pc)
1250 {
1251 struct objfile_pspace_info *pspace_info;
1252 struct obj_section *s, **sp;
1253
1254 /* Check for mapped overlay section first. */
1255 s = find_pc_mapped_section (pc);
1256 if (s)
1257 return s;
1258
1259 pspace_info = get_objfile_pspace_data (current_program_space);
1260 if (pspace_info->section_map_dirty
1261 || (pspace_info->new_objfiles_available
1262 && !pspace_info->inhibit_updates))
1263 {
1264 update_section_map (current_program_space,
1265 &pspace_info->sections,
1266 &pspace_info->num_sections);
1267
1268 /* Don't need updates to section map until objfiles are added,
1269 removed or relocated. */
1270 pspace_info->new_objfiles_available = 0;
1271 pspace_info->section_map_dirty = 0;
1272 }
1273
1274 /* The C standard (ISO/IEC 9899:TC2) requires the BASE argument to
1275 bsearch be non-NULL. */
1276 if (pspace_info->sections == NULL)
1277 {
1278 gdb_assert (pspace_info->num_sections == 0);
1279 return NULL;
1280 }
1281
1282 sp = (struct obj_section **) bsearch (&pc,
1283 pspace_info->sections,
1284 pspace_info->num_sections,
1285 sizeof (*pspace_info->sections),
1286 bsearch_cmp);
1287 if (sp != NULL)
1288 return *sp;
1289 return NULL;
1290 }
1291
1292
1293 /* Return non-zero if PC is in a section called NAME. */
1294
1295 int
1296 pc_in_section (CORE_ADDR pc, const char *name)
1297 {
1298 struct obj_section *s;
1299 int retval = 0;
1300
1301 s = find_pc_section (pc);
1302
1303 retval = (s != NULL
1304 && s->the_bfd_section->name != NULL
1305 && strcmp (s->the_bfd_section->name, name) == 0);
1306 return (retval);
1307 }
1308 \f
1309
1310 /* Set section_map_dirty so section map will be rebuilt next time it
1311 is used. Called by reread_symbols. */
1312
1313 void
1314 objfiles_changed (void)
1315 {
1316 /* Rebuild section map next time we need it. */
1317 get_objfile_pspace_data (current_program_space)->section_map_dirty = 1;
1318 }
1319
1320 /* See comments in objfiles.h. */
1321
1322 scoped_restore_tmpl<int>
1323 inhibit_section_map_updates (struct program_space *pspace)
1324 {
1325 return scoped_restore_tmpl<int>
1326 (&get_objfile_pspace_data (pspace)->inhibit_updates, 1);
1327 }
1328
1329 /* Return 1 if ADDR maps into one of the sections of OBJFILE and 0
1330 otherwise. */
1331
1332 int
1333 is_addr_in_objfile (CORE_ADDR addr, const struct objfile *objfile)
1334 {
1335 struct obj_section *osect;
1336
1337 if (objfile == NULL)
1338 return 0;
1339
1340 ALL_OBJFILE_OSECTIONS (objfile, osect)
1341 {
1342 if (section_is_overlay (osect) && !section_is_mapped (osect))
1343 continue;
1344
1345 if (obj_section_addr (osect) <= addr
1346 && addr < obj_section_endaddr (osect))
1347 return 1;
1348 }
1349 return 0;
1350 }
1351
1352 int
1353 shared_objfile_contains_address_p (struct program_space *pspace,
1354 CORE_ADDR address)
1355 {
1356 for (objfile *objfile : pspace->objfiles ())
1357 {
1358 if ((objfile->flags & OBJF_SHARED) != 0
1359 && is_addr_in_objfile (address, objfile))
1360 return 1;
1361 }
1362
1363 return 0;
1364 }
1365
1366 /* The default implementation for the "iterate_over_objfiles_in_search_order"
1367 gdbarch method. It is equivalent to use the objfiles iterable,
1368 searching the objfiles in the order they are stored internally,
1369 ignoring CURRENT_OBJFILE.
1370
1371 On most platforms, it should be close enough to doing the best
1372 we can without some knowledge specific to the architecture. */
1373
1374 void
1375 default_iterate_over_objfiles_in_search_order
1376 (struct gdbarch *gdbarch,
1377 iterate_over_objfiles_in_search_order_cb_ftype *cb,
1378 void *cb_data, struct objfile *current_objfile)
1379 {
1380 int stop = 0;
1381
1382 for (objfile *objfile : current_program_space->objfiles ())
1383 {
1384 stop = cb (objfile, cb_data);
1385 if (stop)
1386 return;
1387 }
1388 }
1389
1390 /* See objfiles.h. */
1391
1392 const char *
1393 objfile_name (const struct objfile *objfile)
1394 {
1395 if (objfile->obfd != NULL)
1396 return bfd_get_filename (objfile->obfd);
1397
1398 return objfile->original_name;
1399 }
1400
1401 /* See objfiles.h. */
1402
1403 const char *
1404 objfile_filename (const struct objfile *objfile)
1405 {
1406 if (objfile->obfd != NULL)
1407 return bfd_get_filename (objfile->obfd);
1408
1409 return NULL;
1410 }
1411
1412 /* See objfiles.h. */
1413
1414 const char *
1415 objfile_debug_name (const struct objfile *objfile)
1416 {
1417 return lbasename (objfile->original_name);
1418 }
1419
1420 /* See objfiles.h. */
1421
1422 const char *
1423 objfile_flavour_name (struct objfile *objfile)
1424 {
1425 if (objfile->obfd != NULL)
1426 return bfd_flavour_name (bfd_get_flavour (objfile->obfd));
1427 return NULL;
1428 }
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