1 /* Copyright (C) 2013-2015 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. */
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 struct lm_info *lm_info_p;
64 /* Return a deep copy of the given struct lm_info object. */
66 static struct lm_info *
67 solib_aix_new_lm_info (struct lm_info *info)
69 struct lm_info *result = XNEW (struct lm_info);
71 memcpy (result, info, sizeof (struct lm_info));
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 (struct lm_info *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_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 = inferior_data (inf, solib_aix_inferior_data_handle);
118 data = XCNEW (struct solib_aix_inferior_data);
119 set_inferior_data (inf, solib_aix_inferior_data_handle, data);
125 #if !defined(HAVE_LIBEXPAT)
127 /* Dummy implementation if XML support is not compiled in. */
129 static VEC (lm_info_p) *
130 solib_aix_parse_libraries (const char *library)
132 static int have_warned;
137 warning (_("Can not parse XML library list; XML support was disabled "
144 /* Dummy implementation if XML support is not compiled in. */
147 solib_aix_free_library_list (void *p)
151 #else /* HAVE_LIBEXPAT */
153 #include "xml-support.h"
155 /* Handle the start of a <library> element. */
158 library_list_start_library (struct gdb_xml_parser *parser,
159 const struct gdb_xml_element *element,
161 VEC (gdb_xml_value_s) *attributes)
163 VEC (lm_info_p) **list = user_data;
164 struct lm_info *item = XCNEW (struct lm_info);
165 struct gdb_xml_value *attr;
167 attr = xml_find_attribute (attributes, "name");
168 item->filename = xstrdup (attr->value);
170 attr = xml_find_attribute (attributes, "member");
172 item->member_name = xstrdup (attr->value);
174 attr = xml_find_attribute (attributes, "text_addr");
175 item->text_addr = * (ULONGEST *) attr->value;
177 attr = xml_find_attribute (attributes, "text_size");
178 item->text_size = * (ULONGEST *) attr->value;
180 attr = xml_find_attribute (attributes, "data_addr");
181 item->data_addr = * (ULONGEST *) attr->value;
183 attr = xml_find_attribute (attributes, "data_size");
184 item->data_size = * (ULONGEST *) attr->value;
186 VEC_safe_push (lm_info_p, *list, item);
189 /* Handle the start of a <library-list-aix> element. */
192 library_list_start_list (struct gdb_xml_parser *parser,
193 const struct gdb_xml_element *element,
194 void *user_data, VEC (gdb_xml_value_s) *attributes)
196 char *version = xml_find_attribute (attributes, "version")->value;
198 if (strcmp (version, "1.0") != 0)
199 gdb_xml_error (parser,
200 _("Library list has unsupported version \"%s\""),
204 /* Discard the constructed library list. */
207 solib_aix_free_library_list (void *p)
209 VEC (lm_info_p) **result = p;
210 struct lm_info *info;
214 fprintf_unfiltered (gdb_stdlog, "DEBUG: solib_aix_free_library_list\n");
216 for (ix = 0; VEC_iterate (lm_info_p, *result, ix, info); ix++)
217 solib_aix_xfree_lm_info (info);
218 VEC_free (lm_info_p, *result);
222 /* The allowed elements and attributes for an AIX library list
223 described in XML format. The root element is a <library-list-aix>. */
225 static const struct gdb_xml_attribute library_attributes[] =
227 { "name", GDB_XML_AF_NONE, NULL, NULL },
228 { "member", GDB_XML_AF_OPTIONAL, NULL, NULL },
229 { "text_addr", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
230 { "text_size", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
231 { "data_addr", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
232 { "data_size", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
233 { NULL, GDB_XML_AF_NONE, NULL, NULL }
236 static const struct gdb_xml_element library_list_children[] =
238 { "library", library_attributes, NULL,
239 GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL,
240 library_list_start_library, NULL},
241 { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
244 static const struct gdb_xml_attribute library_list_attributes[] =
246 { "version", GDB_XML_AF_NONE, NULL, NULL },
247 { NULL, GDB_XML_AF_NONE, NULL, NULL }
250 static const struct gdb_xml_element library_list_elements[] =
252 { "library-list-aix", library_list_attributes, library_list_children,
253 GDB_XML_EF_NONE, library_list_start_list, NULL },
254 { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
257 /* Parse LIBRARY, a string containing the loader info in XML format,
258 and return an lm_info_p vector.
260 Return NULL if the parsing failed. */
262 static VEC (lm_info_p) *
263 solib_aix_parse_libraries (const char *library)
265 VEC (lm_info_p) *result = NULL;
266 struct cleanup *back_to = make_cleanup (solib_aix_free_library_list,
269 if (gdb_xml_parse_quick (_("aix library list"), "library-list-aix.dtd",
270 library_list_elements, library, &result) == 0)
272 /* Parsed successfully, keep the result. */
273 discard_cleanups (back_to);
277 do_cleanups (back_to);
281 #endif /* HAVE_LIBEXPAT */
283 /* Return the loader info for the given inferior (INF), or NULL if
284 the list could not be computed.
286 Cache the result in per-inferior data, so as to avoid recomputing it
287 each time this function is called.
289 If an error occurs while computing this list, and WARNING_MSG
290 is not NULL, then print a warning including WARNING_MSG and
291 a description of the error. */
293 static VEC (lm_info_p) *
294 solib_aix_get_library_list (struct inferior *inf, const char *warning_msg)
296 struct solib_aix_inferior_data *data;
297 char *library_document;
298 struct cleanup *cleanup;
300 /* If already computed, return the cached value. */
301 data = get_solib_aix_inferior_data (inf);
302 if (data->library_list != NULL)
303 return data->library_list;
305 library_document = target_read_stralloc (¤t_target,
306 TARGET_OBJECT_LIBRARIES_AIX,
308 if (library_document == NULL && warning_msg != NULL)
310 warning (_("%s (failed to read TARGET_OBJECT_LIBRARIES_AIX)"),
314 cleanup = make_cleanup (xfree, library_document);
317 fprintf_unfiltered (gdb_stdlog,
318 "DEBUG: TARGET_OBJECT_LIBRARIES_AIX = \n%s\n",
321 data->library_list = solib_aix_parse_libraries (library_document);
322 if (data->library_list == NULL && warning_msg != NULL)
324 warning (_("%s (missing XML support?)"), warning_msg);
325 do_cleanups (cleanup);
329 do_cleanups (cleanup);
330 return data->library_list;
333 /* If the .bss section's VMA is set to an address located before
334 the end of the .data section, causing the two sections to overlap,
335 return the overlap in bytes. Otherwise, return zero.
339 The GNU linker sometimes sets the start address of the .bss session
340 before the end of the .data section, making the 2 sections overlap.
341 The loader appears to handle this situation gracefully, by simply
342 loading the bss section right after the end of the .data section.
344 This means that the .data and the .bss sections are sometimes
345 no longer relocated by the same amount. The problem is that
346 the ldinfo data does not contain any information regarding
347 the relocation of the .bss section, assuming that it would be
348 identical to the information provided for the .data section
349 (this is what would normally happen if the program was linked
352 GDB therefore needs to detect those cases, and make the corresponding
353 adjustment to the .bss section offset computed from the ldinfo data
354 when necessary. This function returns the adjustment amount (or
355 zero when no adjustment is needed). */
358 solib_aix_bss_data_overlap (bfd *abfd)
360 struct bfd_section *data_sect, *bss_sect;
362 data_sect = bfd_get_section_by_name (abfd, ".data");
363 if (data_sect == NULL)
364 return 0; /* No overlap possible. */
366 bss_sect = bfd_get_section_by_name (abfd, ".bss");
367 if (bss_sect == NULL)
368 return 0; /* No overlap possible. */
370 /* Assume the problem only occurs with linkers that place the .bss
371 section after the .data section (the problem has only been
372 observed when using the GNU linker, and the default linker
373 script always places the .data and .bss sections in that order). */
374 if (bfd_section_vma (abfd, bss_sect)
375 < bfd_section_vma (abfd, data_sect))
378 if (bfd_section_vma (abfd, bss_sect)
379 < bfd_section_vma (abfd, data_sect) + bfd_get_section_size (data_sect))
380 return ((bfd_section_vma (abfd, data_sect)
381 + bfd_get_section_size (data_sect))
382 - bfd_section_vma (abfd, bss_sect));
387 /* Implement the "relocate_section_addresses" target_so_ops method. */
390 solib_aix_relocate_section_addresses (struct so_list *so,
391 struct target_section *sec)
393 struct bfd_section *bfd_sect = sec->the_bfd_section;
394 bfd *abfd = bfd_sect->owner;
395 const char *section_name = bfd_section_name (abfd, bfd_sect);
396 struct lm_info *info = so->lm_info;
398 if (strcmp (section_name, ".text") == 0)
400 sec->addr = info->text_addr;
401 sec->endaddr = sec->addr + info->text_size;
403 /* The text address given to us by the loader contains
404 XCOFF headers, so we need to adjust by this much. */
405 sec->addr += bfd_sect->filepos;
407 else if (strcmp (section_name, ".data") == 0)
409 sec->addr = info->data_addr;
410 sec->endaddr = sec->addr + info->data_size;
412 else if (strcmp (section_name, ".bss") == 0)
414 /* The information provided by the loader does not include
415 the address of the .bss section, but we know that it gets
416 relocated by the same offset as the .data section. So,
417 compute the relocation offset for the .data section, and
418 apply it to the .bss section as well. If the .data section
419 is not defined (which seems highly unlikely), do our best
420 by assuming no relocation. */
421 struct bfd_section *data_sect
422 = bfd_get_section_by_name (abfd, ".data");
423 CORE_ADDR data_offset = 0;
425 if (data_sect != NULL)
426 data_offset = info->data_addr - bfd_section_vma (abfd, data_sect);
428 sec->addr = bfd_section_vma (abfd, bfd_sect) + data_offset;
429 sec->addr += solib_aix_bss_data_overlap (abfd);
430 sec->endaddr = sec->addr + bfd_section_size (abfd, bfd_sect);
434 /* All other sections should not be relocated. */
435 sec->addr = bfd_section_vma (abfd, bfd_sect);
436 sec->endaddr = sec->addr + bfd_section_size (abfd, bfd_sect);
440 /* Implement the "free_so" target_so_ops method. */
443 solib_aix_free_so (struct so_list *so)
446 fprintf_unfiltered (gdb_stdlog, "DEBUG: solib_aix_free_so (%s)\n",
448 solib_aix_xfree_lm_info (so->lm_info);
451 /* Implement the "clear_solib" target_so_ops method. */
454 solib_aix_clear_solib (void)
456 /* Nothing needed. */
459 /* Compute and return the OBJFILE's section_offset array, using
460 the associated loader info (INFO).
462 The resulting array is computed on the heap and must be
463 deallocated after use. */
465 static struct section_offsets *
466 solib_aix_get_section_offsets (struct objfile *objfile,
467 struct lm_info *info)
469 struct section_offsets *offsets;
470 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_p) *library_list;
523 struct lm_info *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_p, library_list) < 1)
534 warning (_("unable to relocate main executable (no info from loader)"));
538 exec_info = VEC_index (lm_info_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 "special_symbol_handling" target_so_ops method. */
554 solib_aix_special_symbol_handling (void)
556 /* Nothing needed. */
559 /* Implement the "current_sos" target_so_ops method. */
561 static struct so_list *
562 solib_aix_current_sos (void)
564 struct so_list *start = NULL, *last = NULL;
565 VEC (lm_info_p) *library_list;
566 struct lm_info *info;
569 library_list = solib_aix_get_library_list (current_inferior (), NULL);
570 if (library_list == NULL)
573 /* Build a struct so_list for each entry on the list.
574 We skip the first entry, since this is the entry corresponding
575 to the main executable, not a shared library. */
576 for (ix = 1; VEC_iterate (lm_info_p, library_list, ix, info); ix++)
578 struct so_list *new_solib = XCNEW (struct so_list);
581 if (info->member_name == NULL)
583 /* INFO->FILENAME is probably not an archive, but rather
584 a shared object. Unusual, but it should be possible
585 to link a program against a shared object directory,
586 without having to put it in an archive first. */
587 so_name = xstrdup (info->filename);
591 /* This is the usual case on AIX, where the shared object
592 is a member of an archive. Create a synthetic so_name
593 that follows the same convention as AIX's ldd tool
594 (Eg: "/lib/libc.a(shr.o)"). */
595 so_name = xstrprintf ("%s(%s)", info->filename, info->member_name);
597 strncpy (new_solib->so_original_name, so_name,
598 SO_NAME_MAX_PATH_SIZE - 1);
599 new_solib->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
600 memcpy (new_solib->so_name, new_solib->so_original_name,
601 SO_NAME_MAX_PATH_SIZE);
602 new_solib->lm_info = solib_aix_new_lm_info (info);
604 /* Add it to the list. */
606 last = start = new_solib;
609 last->next = new_solib;
617 /* Implement the "open_symbol_file_object" target_so_ops method. */
620 solib_aix_open_symbol_file_object (void *from_ttyp)
625 /* Implement the "in_dynsym_resolve_code" target_so_ops method. */
628 solib_aix_in_dynsym_resolve_code (CORE_ADDR pc)
633 /* Implement the "bfd_open" target_so_ops method. */
636 solib_aix_bfd_open (char *pathname)
638 /* The pathname is actually a synthetic filename with the following
639 form: "/path/to/sharedlib(member.o)" (double-quotes excluded).
640 split this into archive name and member name.
642 FIXME: This is a little hacky. Perhaps we should provide access
643 to the solib's lm_info here? */
644 const int path_len = strlen (pathname);
649 bfd *archive_bfd, *object_bfd;
650 struct cleanup *cleanup;
652 if (pathname[path_len - 1] != ')')
653 return solib_bfd_open (pathname);
655 /* Search for the associated parens. */
656 sep = strrchr (pathname, '(');
659 /* Should never happen, but recover as best as we can (trying
660 to open pathname without decoding, possibly leading to
661 a failure), rather than triggering an assert failure). */
662 warning (_("missing '(' in shared object pathname: %s"), pathname);
663 return solib_bfd_open (pathname);
665 filename_len = sep - pathname;
667 filename = xstrprintf ("%.*s", filename_len, pathname);
668 cleanup = make_cleanup (xfree, filename);
669 member_name = xstrprintf ("%.*s", path_len - filename_len - 2, sep + 1);
670 make_cleanup (xfree, member_name);
672 archive_bfd = gdb_bfd_open (filename, gnutarget, -1);
673 if (archive_bfd == NULL)
675 warning (_("Could not open `%s' as an executable file: %s"),
676 filename, bfd_errmsg (bfd_get_error ()));
677 do_cleanups (cleanup);
681 if (bfd_check_format (archive_bfd, bfd_object))
683 do_cleanups (cleanup);
687 if (! bfd_check_format (archive_bfd, bfd_archive))
689 warning (_("\"%s\": not in executable format: %s."),
690 filename, bfd_errmsg (bfd_get_error ()));
691 gdb_bfd_unref (archive_bfd);
692 do_cleanups (cleanup);
696 object_bfd = gdb_bfd_openr_next_archived_file (archive_bfd, NULL);
697 while (object_bfd != NULL)
701 if (strcmp (member_name, object_bfd->filename) == 0)
704 next = gdb_bfd_openr_next_archived_file (archive_bfd, object_bfd);
705 gdb_bfd_unref (object_bfd);
709 if (object_bfd == NULL)
711 warning (_("\"%s\": member \"%s\" missing."), filename, member_name);
712 gdb_bfd_unref (archive_bfd);
713 do_cleanups (cleanup);
717 if (! bfd_check_format (object_bfd, bfd_object))
719 warning (_("%s(%s): not in object format: %s."),
720 filename, member_name, bfd_errmsg (bfd_get_error ()));
721 gdb_bfd_unref (archive_bfd);
722 gdb_bfd_unref (object_bfd);
723 do_cleanups (cleanup);
727 /* Override the returned bfd's name with our synthetic name in order
728 to allow commands listing all shared libraries to display that
729 synthetic name. Otherwise, we would only be displaying the name
730 of the archive member object. */
731 xfree (bfd_get_filename (object_bfd));
732 object_bfd->filename = xstrdup (pathname);
734 gdb_bfd_unref (archive_bfd);
735 do_cleanups (cleanup);
739 /* Return the obj_section corresponding to OBJFILE's data section,
740 or NULL if not found. */
741 /* FIXME: Define in a more general location? */
743 static struct obj_section *
744 data_obj_section_from_objfile (struct objfile *objfile)
746 struct obj_section *osect;
748 ALL_OBJFILE_OSECTIONS (objfile, osect)
749 if (strcmp (bfd_section_name (objfile->obfd, osect->the_bfd_section),
756 /* Return the TOC value corresponding to the given PC address,
757 or raise an error if the value could not be determined. */
760 solib_aix_get_toc_value (CORE_ADDR pc)
762 struct obj_section *pc_osect = find_pc_section (pc);
763 struct obj_section *data_osect;
766 if (pc_osect == NULL)
767 error (_("unable to find TOC entry for pc %s "
768 "(no section contains this PC)"),
769 core_addr_to_string (pc));
771 data_osect = data_obj_section_from_objfile (pc_osect->objfile);
772 if (data_osect == NULL)
773 error (_("unable to find TOC entry for pc %s "
774 "(%s has no data section)"),
775 core_addr_to_string (pc), objfile_name (pc_osect->objfile));
777 result = (obj_section_addr (data_osect)
778 + xcoff_get_toc_offset (pc_osect->objfile));
780 fprintf_unfiltered (gdb_stdlog,
781 "DEBUG: solib_aix_get_toc_value (pc=%s) -> %s\n",
782 core_addr_to_string (pc),
783 core_addr_to_string (result));
788 /* This module's normal_stop observer. */
791 solib_aix_normal_stop_observer (struct bpstats *unused_1, int unused_2)
793 struct solib_aix_inferior_data *data
794 = get_solib_aix_inferior_data (current_inferior ());
796 /* The inferior execution has been resumed, and it just stopped
797 again. This means that the list of shared libraries may have
798 evolved. Reset our cached value. */
799 solib_aix_free_library_list (&data->library_list);
802 /* Implements the "show debug aix-solib" command. */
805 show_solib_aix_debug (struct ui_file *file, int from_tty,
806 struct cmd_list_element *c, const char *value)
808 fprintf_filtered (file, _("solib-aix debugging is %s.\n"), value);
811 /* The target_so_ops for AIX targets. */
812 struct target_so_ops solib_aix_so_ops;
814 /* -Wmissing-prototypes */
815 extern initialize_file_ftype _initialize_solib_aix;
818 _initialize_solib_aix (void)
820 solib_aix_so_ops.relocate_section_addresses
821 = solib_aix_relocate_section_addresses;
822 solib_aix_so_ops.free_so = solib_aix_free_so;
823 solib_aix_so_ops.clear_solib = solib_aix_clear_solib;
824 solib_aix_so_ops.solib_create_inferior_hook
825 = solib_aix_solib_create_inferior_hook;
826 solib_aix_so_ops.special_symbol_handling
827 = solib_aix_special_symbol_handling;
828 solib_aix_so_ops.current_sos = solib_aix_current_sos;
829 solib_aix_so_ops.open_symbol_file_object
830 = solib_aix_open_symbol_file_object;
831 solib_aix_so_ops.in_dynsym_resolve_code
832 = solib_aix_in_dynsym_resolve_code;
833 solib_aix_so_ops.bfd_open = solib_aix_bfd_open;
835 solib_aix_inferior_data_handle = register_inferior_data ();
837 observer_attach_normal_stop (solib_aix_normal_stop_observer);
839 /* Debug this file's internals. */
840 add_setshow_boolean_cmd ("aix-solib", class_maintenance,
841 &solib_aix_debug, _("\
842 Control the debugging traces for the solib-aix module."), _("\
843 Show whether solib-aix debugging traces are enabled."), _("\
844 When on, solib-aix debugging traces are enabled."),
846 show_solib_aix_debug,
847 &setdebuglist, &showdebuglist);