1 /* Definitions for BFD wrappers used by GDB.
3 Copyright (C) 2011, 2012
4 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
23 #include "gdb_assert.h"
24 #include "gdb_string.h"
34 #define MAP_FAILED ((void *) -1)
38 /* An object of this type is stored in the section's user data when
41 struct gdb_bfd_section_data
43 /* Size of the data. */
45 /* If the data was mmapped, this is the length of the map. */
46 bfd_size_type map_len
;
47 /* The data. If NULL, the section data has not been read. */
49 /* If the data was mmapped, this is the map address. */
53 /* A hash table holding every BFD that gdb knows about. This is not
54 to be confused with 'gdb_bfd_cache', which is used for sharing
55 BFDs; in contrast, this hash is used just to implement
58 static htab_t all_bfds
;
63 gdb_bfd_stash_filename (struct bfd
*abfd
)
65 char *name
= bfd_get_filename (abfd
);
68 data
= bfd_alloc (abfd
, strlen (name
) + 1);
71 /* Unwarranted chumminess with BFD. */
72 abfd
->filename
= data
;
75 /* An object of this type is stored in each BFD's user data. */
79 /* The reference count. */
82 /* The mtime of the BFD at the point the cache entry was made. */
85 /* If the BFD comes from an archive, this points to the archive's
86 BFD. Otherwise, this is NULL. */
93 #define GDB_BFD_DATA_ACCESSOR(ABFD) \
94 ((struct gdb_bfd_data *) bfd_usrdata (ABFD))
96 DEFINE_REGISTRY (bfd
, GDB_BFD_DATA_ACCESSOR
)
98 /* A hash table storing all the BFDs maintained in the cache. */
100 static htab_t gdb_bfd_cache
;
102 /* The type of an object being looked up in gdb_bfd_cache. We use
103 htab's capability of storing one kind of object (BFD in this case)
104 and using a different sort of object for searching. */
106 struct gdb_bfd_cache_search
109 const char *filename
;
114 /* A hash function for BFDs. */
117 hash_bfd (const void *b
)
121 /* It is simplest to just hash the filename. */
122 return htab_hash_string (bfd_get_filename (abfd
));
125 /* An equality function for BFDs. Note that this expects the caller
126 to search using struct gdb_bfd_cache_search only, not BFDs. */
129 eq_bfd (const void *a
, const void *b
)
132 const struct gdb_bfd_cache_search
*s
= b
;
133 struct gdb_bfd_data
*gdata
= bfd_usrdata (abfd
);
135 return (gdata
->mtime
== s
->mtime
136 && strcmp (bfd_get_filename (abfd
), s
->filename
) == 0);
142 gdb_bfd_open (const char *name
, const char *target
, int fd
)
147 struct gdb_bfd_cache_search search
;
150 if (gdb_bfd_cache
== NULL
)
151 gdb_bfd_cache
= htab_create_alloc (1, hash_bfd
, eq_bfd
, NULL
,
156 fd
= open (name
, O_RDONLY
| O_BINARY
);
159 bfd_set_error (bfd_error_system_call
);
164 search
.filename
= name
;
165 if (fstat (fd
, &st
) < 0)
167 /* Weird situation here. */
171 search
.mtime
= st
.st_mtime
;
173 /* Note that this must compute the same result as hash_bfd. */
174 hash
= htab_hash_string (name
);
175 /* Note that we cannot use htab_find_slot_with_hash here, because
176 opening the BFD may fail; and this would violate hashtab
178 abfd
= htab_find_with_hash (gdb_bfd_cache
, &search
, hash
);
186 abfd
= bfd_fopen (name
, target
, FOPEN_RB
, fd
);
190 slot
= htab_find_slot_with_hash (gdb_bfd_cache
, &search
, hash
, INSERT
);
194 gdb_bfd_stash_filename (abfd
);
199 /* A helper function that releases any section data attached to the
203 free_one_bfd_section (bfd
*abfd
, asection
*sectp
, void *ignore
)
205 struct gdb_bfd_section_data
*sect
= bfd_get_section_userdata (abfd
, sectp
);
207 if (sect
!= NULL
&& sect
->data
!= NULL
)
210 if (sect
->map_addr
!= NULL
)
214 res
= munmap (sect
->map_addr
, sect
->map_len
);
215 gdb_assert (res
== 0);
223 /* Close ABFD, and warn if that fails. */
226 gdb_bfd_close_or_warn (struct bfd
*abfd
)
229 char *name
= bfd_get_filename (abfd
);
231 bfd_map_over_sections (abfd
, free_one_bfd_section
, NULL
);
233 ret
= bfd_close (abfd
);
236 warning (_("cannot close \"%s\": %s"),
237 name
, bfd_errmsg (bfd_get_error ()));
245 gdb_bfd_ref (struct bfd
*abfd
)
247 struct gdb_bfd_data
*gdata
;
253 gdata
= bfd_usrdata (abfd
);
261 /* Ask BFD to decompress sections in bfd_get_full_section_contents. */
262 abfd
->flags
|= BFD_DECOMPRESS
;
264 gdata
= bfd_zalloc (abfd
, sizeof (struct gdb_bfd_data
));
266 gdata
->mtime
= bfd_get_mtime (abfd
);
267 gdata
->archive_bfd
= NULL
;
268 bfd_usrdata (abfd
) = gdata
;
270 bfd_alloc_data (abfd
);
272 /* This is the first we've seen it, so add it to the hash table. */
273 slot
= htab_find_slot (all_bfds
, abfd
, INSERT
);
274 gdb_assert (slot
&& !*slot
);
281 gdb_bfd_unref (struct bfd
*abfd
)
283 struct gdb_bfd_data
*gdata
;
284 struct gdb_bfd_cache_search search
;
290 gdata
= bfd_usrdata (abfd
);
291 gdb_assert (gdata
->refc
>= 1);
297 archive_bfd
= gdata
->archive_bfd
;
298 search
.filename
= bfd_get_filename (abfd
);
300 if (gdb_bfd_cache
&& search
.filename
)
302 hashval_t hash
= htab_hash_string (search
.filename
);
305 search
.mtime
= gdata
->mtime
;
306 slot
= htab_find_slot_with_hash (gdb_bfd_cache
, &search
, hash
,
310 htab_clear_slot (gdb_bfd_cache
, slot
);
313 bfd_free_data (abfd
);
314 bfd_usrdata (abfd
) = NULL
; /* Paranoia. */
316 htab_remove_elt (all_bfds
, abfd
);
318 gdb_bfd_close_or_warn (abfd
);
320 gdb_bfd_unref (archive_bfd
);
323 /* A helper function that returns the section data descriptor
324 associated with SECTION. If no such descriptor exists, a new one
325 is allocated and cleared. */
327 static struct gdb_bfd_section_data
*
328 get_section_descriptor (asection
*section
)
330 struct gdb_bfd_section_data
*result
;
332 result
= bfd_get_section_userdata (section
->owner
, section
);
336 result
= bfd_zalloc (section
->owner
, sizeof (*result
));
337 bfd_set_section_userdata (section
->owner
, section
, result
);
346 gdb_bfd_map_section (asection
*sectp
, bfd_size_type
*size
)
349 unsigned char header
[4];
350 struct gdb_bfd_section_data
*descriptor
;
353 gdb_assert ((sectp
->flags
& SEC_RELOC
) == 0);
354 gdb_assert (size
!= NULL
);
358 descriptor
= get_section_descriptor (sectp
);
360 /* If the data was already read for this BFD, just reuse it. */
361 if (descriptor
->data
!= NULL
)
365 if (!bfd_is_section_compressed (abfd
, sectp
))
367 /* The page size, used when mmapping. */
371 pagesize
= getpagesize ();
373 /* Only try to mmap sections which are large enough: we don't want
374 to waste space due to fragmentation. */
376 if (bfd_get_section_size (sectp
) > 4 * pagesize
)
378 descriptor
->size
= bfd_get_section_size (sectp
);
379 descriptor
->data
= bfd_mmap (abfd
, 0, descriptor
->size
, PROT_READ
,
380 MAP_PRIVATE
, sectp
->filepos
,
381 &descriptor
->map_addr
,
382 &descriptor
->map_len
);
384 if ((caddr_t
)descriptor
->data
!= MAP_FAILED
)
386 #if HAVE_POSIX_MADVISE
387 posix_madvise (descriptor
->map_addr
, descriptor
->map_len
,
388 POSIX_MADV_WILLNEED
);
393 /* On failure, clear out the section data and try again. */
394 memset (descriptor
, 0, sizeof (*descriptor
));
397 #endif /* HAVE_MMAP */
399 /* Handle compressed sections, or ordinary uncompressed sections in
402 descriptor
->size
= bfd_get_section_size (sectp
);
403 descriptor
->data
= NULL
;
406 if (!bfd_get_full_section_contents (abfd
, sectp
, &data
))
407 error (_("Can't read data for section '%s' in file '%s'"),
408 bfd_get_section_name (abfd
, sectp
),
409 bfd_get_filename (abfd
));
410 descriptor
->data
= data
;
413 gdb_assert (descriptor
->data
!= NULL
);
414 *size
= descriptor
->size
;
415 return descriptor
->data
;
423 gdb_bfd_fopen (const char *filename
, const char *target
, const char *mode
,
426 bfd
*result
= bfd_fopen (filename
, target
, mode
, fd
);
430 gdb_bfd_stash_filename (result
);
431 gdb_bfd_ref (result
);
440 gdb_bfd_openr (const char *filename
, const char *target
)
442 bfd
*result
= bfd_openr (filename
, target
);
446 gdb_bfd_stash_filename (result
);
447 gdb_bfd_ref (result
);
456 gdb_bfd_openw (const char *filename
, const char *target
)
458 bfd
*result
= bfd_openw (filename
, target
);
462 gdb_bfd_stash_filename (result
);
463 gdb_bfd_ref (result
);
472 gdb_bfd_openr_iovec (const char *filename
, const char *target
,
473 void *(*open_func
) (struct bfd
*nbfd
,
476 file_ptr (*pread_func
) (struct bfd
*nbfd
,
481 int (*close_func
) (struct bfd
*nbfd
,
483 int (*stat_func
) (struct bfd
*abfd
,
487 bfd
*result
= bfd_openr_iovec (filename
, target
,
488 open_func
, open_closure
,
489 pread_func
, close_func
, stat_func
);
493 gdb_bfd_ref (result
);
494 gdb_bfd_stash_filename (result
);
503 gdb_bfd_mark_parent (bfd
*child
, bfd
*parent
)
505 struct gdb_bfd_data
*gdata
;
508 /* No need to stash the filename here, because we also keep a
509 reference on the parent archive. */
511 gdata
= bfd_usrdata (child
);
512 if (gdata
->archive_bfd
== NULL
)
514 gdata
->archive_bfd
= parent
;
515 gdb_bfd_ref (parent
);
518 gdb_assert (gdata
->archive_bfd
== parent
);
524 gdb_bfd_openr_next_archived_file (bfd
*archive
, bfd
*previous
)
526 bfd
*result
= bfd_openr_next_archived_file (archive
, previous
);
529 gdb_bfd_mark_parent (result
, archive
);
537 gdb_bfd_fdopenr (const char *filename
, const char *target
, int fd
)
539 bfd
*result
= bfd_fdopenr (filename
, target
, fd
);
543 gdb_bfd_ref (result
);
544 gdb_bfd_stash_filename (result
);
552 /* A callback for htab_traverse that prints a single BFD. */
555 print_one_bfd (void **slot
, void *data
)
558 struct gdb_bfd_data
*gdata
= bfd_usrdata (abfd
);
559 struct ui_out
*uiout
= data
;
560 struct cleanup
*inner
;
562 inner
= make_cleanup_ui_out_tuple_begin_end (uiout
, NULL
);
563 ui_out_field_int (uiout
, "refcount", gdata
->refc
);
564 ui_out_field_string (uiout
, "addr", host_address_to_string (abfd
));
565 ui_out_field_string (uiout
, "filename", bfd_get_filename (abfd
));
566 ui_out_text (uiout
, "\n");
572 /* Implement the 'maint info bfd' command. */
575 maintenance_info_bfds (char *arg
, int from_tty
)
577 struct cleanup
*cleanup
;
578 struct ui_out
*uiout
= current_uiout
;
580 cleanup
= make_cleanup_ui_out_table_begin_end (uiout
, 3, -1, "bfds");
581 ui_out_table_header (uiout
, 10, ui_left
, "refcount", "Refcount");
582 ui_out_table_header (uiout
, 18, ui_left
, "addr", "Address");
583 ui_out_table_header (uiout
, 40, ui_left
, "filename", "Filename");
585 ui_out_table_body (uiout
);
586 htab_traverse (all_bfds
, print_one_bfd
, uiout
);
588 do_cleanups (cleanup
);
591 /* -Wmissing-prototypes */
592 extern initialize_file_ftype _initialize_gdb_bfd
;
595 _initialize_gdb_bfd (void)
597 all_bfds
= htab_create_alloc (10, htab_hash_pointer
, htab_eq_pointer
,
598 NULL
, xcalloc
, xfree
);
600 add_cmd ("bfds", class_maintenance
, maintenance_info_bfds
, _("\
601 List the BFDs that are currently open."),
602 &maintenanceinfolist
);