1 /* Copyright (C) 2013-2017 Free Software Foundation, Inc.
3 This file is part of GDB.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 #include "solib-aix.h"
26 #include "xcoffread.h"
30 /* Variable controlling the output of the debugging traces for
32 static int solib_aix_debug;
34 /* Our private data in struct so_list. */
36 struct lm_info_aix : public lm_info_base
38 /* The name of the file mapped by the loader. Apart from the entry
39 for the main executable, this is usually a shared library (which,
40 on AIX, is an archive library file, created using the "ar"
44 /* The name of the shared object file with the actual dynamic
45 loading dependency. This may be NULL (Eg. main executable). */
48 /* The address in inferior memory where the text section got mapped. */
51 /* The size of the text section, obtained via the loader data. */
54 /* The address in inferior memory where the data section got mapped. */
57 /* The size of the data section, obtained via the loader data. */
61 typedef lm_info_aix *lm_info_aix_p;
62 DEF_VEC_P(lm_info_aix_p);
64 /* Return a deep copy of the given struct lm_info object. */
67 solib_aix_new_lm_info (lm_info_aix *info)
69 lm_info_aix *result = XCNEW (lm_info_aix);
71 memcpy (result, info, sizeof (lm_info_aix));
72 result->filename = xstrdup (info->filename);
73 if (info->member_name != NULL)
74 result->member_name = xstrdup (info->member_name);
79 /* Free the memory allocated for the given lm_info. */
82 solib_aix_xfree_lm_info (lm_info_aix *info)
84 xfree (info->filename);
85 xfree (info->member_name);
89 /* This module's per-inferior data. */
91 struct solib_aix_inferior_data
93 /* The list of shared libraries. NULL if not computed yet.
95 Note that the first element of this list is always the main
96 executable, which is not technically a shared library. But
97 we need that information to perform its relocation, and
98 the same principles applied to shared libraries also apply
99 to the main executable. So it's simpler to keep it as part
101 VEC (lm_info_aix_p) *library_list;
104 /* Key to our per-inferior data. */
105 static const struct inferior_data *solib_aix_inferior_data_handle;
107 /* Return this module's data for the given inferior.
108 If none is found, add a zero'ed one now. */
110 static struct solib_aix_inferior_data *
111 get_solib_aix_inferior_data (struct inferior *inf)
113 struct solib_aix_inferior_data *data;
115 data = ((struct solib_aix_inferior_data *)
116 inferior_data (inf, solib_aix_inferior_data_handle));
119 data = XCNEW (struct solib_aix_inferior_data);
120 set_inferior_data (inf, solib_aix_inferior_data_handle, data);
126 #if !defined(HAVE_LIBEXPAT)
128 /* Dummy implementation if XML support is not compiled in. */
130 static VEC (lm_info_aix_p) *
131 solib_aix_parse_libraries (const char *library)
133 static int have_warned;
138 warning (_("Can not parse XML library list; XML support was disabled "
145 /* Dummy implementation if XML support is not compiled in. */
148 solib_aix_free_library_list (void *p)
152 #else /* HAVE_LIBEXPAT */
154 #include "xml-support.h"
156 /* Handle the start of a <library> element. */
159 library_list_start_library (struct gdb_xml_parser *parser,
160 const struct gdb_xml_element *element,
162 VEC (gdb_xml_value_s) *attributes)
164 VEC (lm_info_aix_p) **list = (VEC (lm_info_aix_p) **) user_data;
165 lm_info_aix *item = XCNEW (lm_info_aix);
166 struct gdb_xml_value *attr;
168 attr = xml_find_attribute (attributes, "name");
169 item->filename = xstrdup ((const char *) attr->value);
171 attr = xml_find_attribute (attributes, "member");
173 item->member_name = xstrdup ((const char *) attr->value);
175 attr = xml_find_attribute (attributes, "text_addr");
176 item->text_addr = * (ULONGEST *) attr->value;
178 attr = xml_find_attribute (attributes, "text_size");
179 item->text_size = * (ULONGEST *) attr->value;
181 attr = xml_find_attribute (attributes, "data_addr");
182 item->data_addr = * (ULONGEST *) attr->value;
184 attr = xml_find_attribute (attributes, "data_size");
185 item->data_size = * (ULONGEST *) attr->value;
187 VEC_safe_push (lm_info_aix_p, *list, item);
190 /* Handle the start of a <library-list-aix> element. */
193 library_list_start_list (struct gdb_xml_parser *parser,
194 const struct gdb_xml_element *element,
195 void *user_data, VEC (gdb_xml_value_s) *attributes)
197 char *version = (char *) xml_find_attribute (attributes, "version")->value;
199 if (strcmp (version, "1.0") != 0)
200 gdb_xml_error (parser,
201 _("Library list has unsupported version \"%s\""),
205 /* Discard the constructed library list. */
208 solib_aix_free_library_list (void *p)
210 VEC (lm_info_aix_p) **result = (VEC (lm_info_aix_p) **) p;
215 fprintf_unfiltered (gdb_stdlog, "DEBUG: solib_aix_free_library_list\n");
217 for (ix = 0; VEC_iterate (lm_info_aix_p, *result, ix, info); ix++)
218 solib_aix_xfree_lm_info (info);
219 VEC_free (lm_info_aix_p, *result);
223 /* The allowed elements and attributes for an AIX library list
224 described in XML format. The root element is a <library-list-aix>. */
226 static const struct gdb_xml_attribute library_attributes[] =
228 { "name", GDB_XML_AF_NONE, NULL, NULL },
229 { "member", GDB_XML_AF_OPTIONAL, NULL, NULL },
230 { "text_addr", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
231 { "text_size", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
232 { "data_addr", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
233 { "data_size", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
234 { NULL, GDB_XML_AF_NONE, NULL, NULL }
237 static const struct gdb_xml_element library_list_children[] =
239 { "library", library_attributes, NULL,
240 GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
241 library_list_start_library, NULL},
242 { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
245 static const struct gdb_xml_attribute library_list_attributes[] =
247 { "version", GDB_XML_AF_NONE, NULL, NULL },
248 { NULL, GDB_XML_AF_NONE, NULL, NULL }
251 static const struct gdb_xml_element library_list_elements[] =
253 { "library-list-aix", library_list_attributes, library_list_children,
254 GDB_XML_EF_NONE, library_list_start_list, NULL },
255 { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
258 /* Parse LIBRARY, a string containing the loader info in XML format,
259 and return an lm_info_aix_p vector.
261 Return NULL if the parsing failed. */
263 static VEC (lm_info_aix_p) *
264 solib_aix_parse_libraries (const char *library)
266 VEC (lm_info_aix_p) *result = NULL;
267 struct cleanup *back_to = make_cleanup (solib_aix_free_library_list,
270 if (gdb_xml_parse_quick (_("aix library list"), "library-list-aix.dtd",
271 library_list_elements, library, &result) == 0)
273 /* Parsed successfully, keep the result. */
274 discard_cleanups (back_to);
278 do_cleanups (back_to);
282 #endif /* HAVE_LIBEXPAT */
284 /* Return the loader info for the given inferior (INF), or NULL if
285 the list could not be computed.
287 Cache the result in per-inferior data, so as to avoid recomputing it
288 each time this function is called.
290 If an error occurs while computing this list, and WARNING_MSG
291 is not NULL, then print a warning including WARNING_MSG and
292 a description of the error. */
294 static VEC (lm_info_aix_p) *
295 solib_aix_get_library_list (struct inferior *inf, const char *warning_msg)
297 struct solib_aix_inferior_data *data;
298 char *library_document;
299 struct cleanup *cleanup;
301 /* If already computed, return the cached value. */
302 data = get_solib_aix_inferior_data (inf);
303 if (data->library_list != NULL)
304 return data->library_list;
306 library_document = target_read_stralloc (¤t_target,
307 TARGET_OBJECT_LIBRARIES_AIX,
309 if (library_document == NULL && warning_msg != NULL)
311 warning (_("%s (failed to read TARGET_OBJECT_LIBRARIES_AIX)"),
315 cleanup = make_cleanup (xfree, library_document);
318 fprintf_unfiltered (gdb_stdlog,
319 "DEBUG: TARGET_OBJECT_LIBRARIES_AIX = \n%s\n",
322 data->library_list = solib_aix_parse_libraries (library_document);
323 if (data->library_list == NULL && warning_msg != NULL)
325 warning (_("%s (missing XML support?)"), warning_msg);
326 do_cleanups (cleanup);
330 do_cleanups (cleanup);
331 return data->library_list;
334 /* If the .bss section's VMA is set to an address located before
335 the end of the .data section, causing the two sections to overlap,
336 return the overlap in bytes. Otherwise, return zero.
340 The GNU linker sometimes sets the start address of the .bss session
341 before the end of the .data section, making the 2 sections overlap.
342 The loader appears to handle this situation gracefully, by simply
343 loading the bss section right after the end of the .data section.
345 This means that the .data and the .bss sections are sometimes
346 no longer relocated by the same amount. The problem is that
347 the ldinfo data does not contain any information regarding
348 the relocation of the .bss section, assuming that it would be
349 identical to the information provided for the .data section
350 (this is what would normally happen if the program was linked
353 GDB therefore needs to detect those cases, and make the corresponding
354 adjustment to the .bss section offset computed from the ldinfo data
355 when necessary. This function returns the adjustment amount (or
356 zero when no adjustment is needed). */
359 solib_aix_bss_data_overlap (bfd *abfd)
361 struct bfd_section *data_sect, *bss_sect;
363 data_sect = bfd_get_section_by_name (abfd, ".data");
364 if (data_sect == NULL)
365 return 0; /* No overlap possible. */
367 bss_sect = bfd_get_section_by_name (abfd, ".bss");
368 if (bss_sect == NULL)
369 return 0; /* No overlap possible. */
371 /* Assume the problem only occurs with linkers that place the .bss
372 section after the .data section (the problem has only been
373 observed when using the GNU linker, and the default linker
374 script always places the .data and .bss sections in that order). */
375 if (bfd_section_vma (abfd, bss_sect)
376 < bfd_section_vma (abfd, data_sect))
379 if (bfd_section_vma (abfd, bss_sect)
380 < bfd_section_vma (abfd, data_sect) + bfd_get_section_size (data_sect))
381 return ((bfd_section_vma (abfd, data_sect)
382 + bfd_get_section_size (data_sect))
383 - bfd_section_vma (abfd, bss_sect));
388 /* Implement the "relocate_section_addresses" target_so_ops method. */
391 solib_aix_relocate_section_addresses (struct so_list *so,
392 struct target_section *sec)
394 struct bfd_section *bfd_sect = sec->the_bfd_section;
395 bfd *abfd = bfd_sect->owner;
396 const char *section_name = bfd_section_name (abfd, bfd_sect);
397 lm_info_aix *info = (lm_info_aix *) so->lm_info;
399 if (strcmp (section_name, ".text") == 0)
401 sec->addr = info->text_addr;
402 sec->endaddr = sec->addr + info->text_size;
404 /* The text address given to us by the loader contains
405 XCOFF headers, so we need to adjust by this much. */
406 sec->addr += bfd_sect->filepos;
408 else if (strcmp (section_name, ".data") == 0)
410 sec->addr = info->data_addr;
411 sec->endaddr = sec->addr + info->data_size;
413 else if (strcmp (section_name, ".bss") == 0)
415 /* The information provided by the loader does not include
416 the address of the .bss section, but we know that it gets
417 relocated by the same offset as the .data section. So,
418 compute the relocation offset for the .data section, and
419 apply it to the .bss section as well. If the .data section
420 is not defined (which seems highly unlikely), do our best
421 by assuming no relocation. */
422 struct bfd_section *data_sect
423 = bfd_get_section_by_name (abfd, ".data");
424 CORE_ADDR data_offset = 0;
426 if (data_sect != NULL)
427 data_offset = info->data_addr - bfd_section_vma (abfd, data_sect);
429 sec->addr = bfd_section_vma (abfd, bfd_sect) + data_offset;
430 sec->addr += solib_aix_bss_data_overlap (abfd);
431 sec->endaddr = sec->addr + bfd_section_size (abfd, bfd_sect);
435 /* All other sections should not be relocated. */
436 sec->addr = bfd_section_vma (abfd, bfd_sect);
437 sec->endaddr = sec->addr + bfd_section_size (abfd, bfd_sect);
441 /* Implement the "free_so" target_so_ops method. */
444 solib_aix_free_so (struct so_list *so)
447 fprintf_unfiltered (gdb_stdlog, "DEBUG: solib_aix_free_so (%s)\n",
449 solib_aix_xfree_lm_info ((lm_info_aix *) so->lm_info);
452 /* Implement the "clear_solib" target_so_ops method. */
455 solib_aix_clear_solib (void)
457 /* Nothing needed. */
460 /* Compute and return the OBJFILE's section_offset array, using
461 the associated loader info (INFO).
463 The resulting array is computed on the heap and must be
464 deallocated after use. */
466 static struct section_offsets *
467 solib_aix_get_section_offsets (struct objfile *objfile,
470 struct section_offsets *offsets;
471 bfd *abfd = objfile->obfd;
473 offsets = XCNEWVEC (struct section_offsets, objfile->num_sections);
477 if (objfile->sect_index_text != -1)
479 struct bfd_section *sect
480 = objfile->sections[objfile->sect_index_text].the_bfd_section;
482 offsets->offsets[objfile->sect_index_text]
483 = info->text_addr + sect->filepos - bfd_section_vma (abfd, sect);
488 if (objfile->sect_index_data != -1)
490 struct bfd_section *sect
491 = objfile->sections[objfile->sect_index_data].the_bfd_section;
493 offsets->offsets[objfile->sect_index_data]
494 = info->data_addr - bfd_section_vma (abfd, sect);
499 The offset of the .bss section should be identical to the offset
500 of the .data section. If no .data section (which seems hard to
501 believe it is possible), assume it is zero. */
503 if (objfile->sect_index_bss != -1
504 && objfile->sect_index_data != -1)
506 offsets->offsets[objfile->sect_index_bss]
507 = (offsets->offsets[objfile->sect_index_data]
508 + solib_aix_bss_data_overlap (abfd));
511 /* All other sections should not need relocation. */
516 /* Implement the "solib_create_inferior_hook" target_so_ops method. */
519 solib_aix_solib_create_inferior_hook (int from_tty)
521 const char *warning_msg = "unable to relocate main executable";
522 VEC (lm_info_aix_p) *library_list;
523 lm_info_aix *exec_info;
525 /* We need to relocate the main executable... */
527 library_list = solib_aix_get_library_list (current_inferior (),
529 if (library_list == NULL)
530 return; /* Warning already printed. */
532 if (VEC_length (lm_info_aix_p, library_list) < 1)
534 warning (_("unable to relocate main executable (no info from loader)"));
538 exec_info = VEC_index (lm_info_aix_p, library_list, 0);
540 if (symfile_objfile != NULL)
542 struct section_offsets *offsets
543 = solib_aix_get_section_offsets (symfile_objfile, exec_info);
544 struct cleanup *cleanup = make_cleanup (xfree, offsets);
546 objfile_relocate (symfile_objfile, offsets);
547 do_cleanups (cleanup);
551 /* Implement the "current_sos" target_so_ops method. */
553 static struct so_list *
554 solib_aix_current_sos (void)
556 struct so_list *start = NULL, *last = NULL;
557 VEC (lm_info_aix_p) *library_list;
561 library_list = solib_aix_get_library_list (current_inferior (), NULL);
562 if (library_list == NULL)
565 /* Build a struct so_list for each entry on the list.
566 We skip the first entry, since this is the entry corresponding
567 to the main executable, not a shared library. */
568 for (ix = 1; VEC_iterate (lm_info_aix_p, library_list, ix, info); ix++)
570 struct so_list *new_solib = XCNEW (struct so_list);
573 if (info->member_name == NULL)
575 /* INFO->FILENAME is probably not an archive, but rather
576 a shared object. Unusual, but it should be possible
577 to link a program against a shared object directory,
578 without having to put it in an archive first. */
579 so_name = xstrdup (info->filename);
583 /* This is the usual case on AIX, where the shared object
584 is a member of an archive. Create a synthetic so_name
585 that follows the same convention as AIX's ldd tool
586 (Eg: "/lib/libc.a(shr.o)"). */
587 so_name = xstrprintf ("%s(%s)", info->filename, info->member_name);
589 strncpy (new_solib->so_original_name, so_name,
590 SO_NAME_MAX_PATH_SIZE - 1);
591 new_solib->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
592 memcpy (new_solib->so_name, new_solib->so_original_name,
593 SO_NAME_MAX_PATH_SIZE);
594 new_solib->lm_info = solib_aix_new_lm_info (info);
596 /* Add it to the list. */
598 last = start = new_solib;
601 last->next = new_solib;
609 /* Implement the "open_symbol_file_object" target_so_ops method. */
612 solib_aix_open_symbol_file_object (void *from_ttyp)
617 /* Implement the "in_dynsym_resolve_code" target_so_ops method. */
620 solib_aix_in_dynsym_resolve_code (CORE_ADDR pc)
625 /* Implement the "bfd_open" target_so_ops method. */
627 static gdb_bfd_ref_ptr
628 solib_aix_bfd_open (char *pathname)
630 /* The pathname is actually a synthetic filename with the following
631 form: "/path/to/sharedlib(member.o)" (double-quotes excluded).
632 split this into archive name and member name.
634 FIXME: This is a little hacky. Perhaps we should provide access
635 to the solib's lm_info here? */
636 const int path_len = strlen (pathname);
640 char *found_pathname;
642 if (pathname[path_len - 1] != ')')
643 return solib_bfd_open (pathname);
645 /* Search for the associated parens. */
646 sep = strrchr (pathname, '(');
649 /* Should never happen, but recover as best as we can (trying
650 to open pathname without decoding, possibly leading to
651 a failure), rather than triggering an assert failure). */
652 warning (_("missing '(' in shared object pathname: %s"), pathname);
653 return solib_bfd_open (pathname);
655 filename_len = sep - pathname;
657 std::string filename (string_printf ("%.*s", filename_len, pathname));
658 std::string member_name (string_printf ("%.*s", path_len - filename_len - 2,
661 /* Calling solib_find makes certain that sysroot path is set properly
662 if program has a dependency on .a archive and sysroot is set via
663 set sysroot command. */
664 found_pathname = solib_find (filename.c_str (), &found_file);
665 if (found_pathname == NULL)
666 perror_with_name (pathname);
667 gdb_bfd_ref_ptr archive_bfd (solib_bfd_fopen (found_pathname, found_file));
668 if (archive_bfd == NULL)
670 warning (_("Could not open `%s' as an executable file: %s"),
671 filename.c_str (), bfd_errmsg (bfd_get_error ()));
675 if (bfd_check_format (archive_bfd.get (), bfd_object))
678 if (! bfd_check_format (archive_bfd.get (), bfd_archive))
680 warning (_("\"%s\": not in executable format: %s."),
681 filename.c_str (), bfd_errmsg (bfd_get_error ()));
685 gdb_bfd_ref_ptr object_bfd
686 (gdb_bfd_openr_next_archived_file (archive_bfd.get (), NULL));
687 while (object_bfd != NULL)
689 if (member_name == object_bfd->filename)
692 object_bfd = gdb_bfd_openr_next_archived_file (archive_bfd.get (),
696 if (object_bfd == NULL)
698 warning (_("\"%s\": member \"%s\" missing."), filename.c_str (),
699 member_name.c_str ());
703 if (! bfd_check_format (object_bfd.get (), bfd_object))
705 warning (_("%s(%s): not in object format: %s."),
706 filename.c_str (), member_name.c_str (),
707 bfd_errmsg (bfd_get_error ()));
711 /* Override the returned bfd's name with the name returned from solib_find
712 along with appended parenthesized member name in order to allow commands
713 listing all shared libraries to display. Otherwise, we would only be
714 displaying the name of the archive member object. */
715 xfree (bfd_get_filename (object_bfd.get ()));
716 object_bfd->filename = xstrprintf ("%s%s",
717 bfd_get_filename (archive_bfd.get ()),
723 /* Return the obj_section corresponding to OBJFILE's data section,
724 or NULL if not found. */
725 /* FIXME: Define in a more general location? */
727 static struct obj_section *
728 data_obj_section_from_objfile (struct objfile *objfile)
730 struct obj_section *osect;
732 ALL_OBJFILE_OSECTIONS (objfile, osect)
733 if (strcmp (bfd_section_name (objfile->obfd, osect->the_bfd_section),
740 /* Return the TOC value corresponding to the given PC address,
741 or raise an error if the value could not be determined. */
744 solib_aix_get_toc_value (CORE_ADDR pc)
746 struct obj_section *pc_osect = find_pc_section (pc);
747 struct obj_section *data_osect;
750 if (pc_osect == NULL)
751 error (_("unable to find TOC entry for pc %s "
752 "(no section contains this PC)"),
753 core_addr_to_string (pc));
755 data_osect = data_obj_section_from_objfile (pc_osect->objfile);
756 if (data_osect == NULL)
757 error (_("unable to find TOC entry for pc %s "
758 "(%s has no data section)"),
759 core_addr_to_string (pc), objfile_name (pc_osect->objfile));
761 result = (obj_section_addr (data_osect)
762 + xcoff_get_toc_offset (pc_osect->objfile));
764 fprintf_unfiltered (gdb_stdlog,
765 "DEBUG: solib_aix_get_toc_value (pc=%s) -> %s\n",
766 core_addr_to_string (pc),
767 core_addr_to_string (result));
772 /* This module's normal_stop observer. */
775 solib_aix_normal_stop_observer (struct bpstats *unused_1, int unused_2)
777 struct solib_aix_inferior_data *data
778 = get_solib_aix_inferior_data (current_inferior ());
780 /* The inferior execution has been resumed, and it just stopped
781 again. This means that the list of shared libraries may have
782 evolved. Reset our cached value. */
783 solib_aix_free_library_list (&data->library_list);
786 /* Implements the "show debug aix-solib" command. */
789 show_solib_aix_debug (struct ui_file *file, int from_tty,
790 struct cmd_list_element *c, const char *value)
792 fprintf_filtered (file, _("solib-aix debugging is %s.\n"), value);
795 /* The target_so_ops for AIX targets. */
796 struct target_so_ops solib_aix_so_ops;
798 /* -Wmissing-prototypes */
799 extern initialize_file_ftype _initialize_solib_aix;
802 _initialize_solib_aix (void)
804 solib_aix_so_ops.relocate_section_addresses
805 = solib_aix_relocate_section_addresses;
806 solib_aix_so_ops.free_so = solib_aix_free_so;
807 solib_aix_so_ops.clear_solib = solib_aix_clear_solib;
808 solib_aix_so_ops.solib_create_inferior_hook
809 = solib_aix_solib_create_inferior_hook;
810 solib_aix_so_ops.current_sos = solib_aix_current_sos;
811 solib_aix_so_ops.open_symbol_file_object
812 = solib_aix_open_symbol_file_object;
813 solib_aix_so_ops.in_dynsym_resolve_code
814 = solib_aix_in_dynsym_resolve_code;
815 solib_aix_so_ops.bfd_open = solib_aix_bfd_open;
817 solib_aix_inferior_data_handle = register_inferior_data ();
819 observer_attach_normal_stop (solib_aix_normal_stop_observer);
821 /* Debug this file's internals. */
822 add_setshow_boolean_cmd ("aix-solib", class_maintenance,
823 &solib_aix_debug, _("\
824 Control the debugging traces for the solib-aix module."), _("\
825 Show whether solib-aix debugging traces are enabled."), _("\
826 When on, solib-aix debugging traces are enabled."),
828 show_solib_aix_debug,
829 &setdebuglist, &showdebuglist);