1 /* Definitions for BFD wrappers used by GDB.
3 Copyright (C) 2011-2013 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "gdb_assert.h"
23 #include "gdb_string.h"
33 #define MAP_FAILED ((void *) -1)
37 /* An object of this type is stored in the section's user data when
40 struct gdb_bfd_section_data
42 /* Size of the data. */
44 /* If the data was mmapped, this is the length of the map. */
45 bfd_size_type map_len
;
46 /* The data. If NULL, the section data has not been read. */
48 /* If the data was mmapped, this is the map address. */
52 /* A hash table holding every BFD that gdb knows about. This is not
53 to be confused with 'gdb_bfd_cache', which is used for sharing
54 BFDs; in contrast, this hash is used just to implement
57 static htab_t all_bfds
;
62 gdb_bfd_stash_filename (struct bfd
*abfd
)
64 char *name
= bfd_get_filename (abfd
);
67 data
= bfd_alloc (abfd
, strlen (name
) + 1);
70 /* Unwarranted chumminess with BFD. */
71 abfd
->filename
= data
;
74 /* An object of this type is stored in each BFD's user data. */
78 /* The reference count. */
81 /* The mtime of the BFD at the point the cache entry was made. */
84 /* This is true if we have successfully computed the file's CRC. */
85 unsigned int crc_computed
: 1;
90 /* If the BFD comes from an archive, this points to the archive's
91 BFD. Otherwise, this is NULL. */
98 #define GDB_BFD_DATA_ACCESSOR(ABFD) \
99 ((struct gdb_bfd_data *) bfd_usrdata (ABFD))
101 DEFINE_REGISTRY (bfd
, GDB_BFD_DATA_ACCESSOR
)
103 /* A hash table storing all the BFDs maintained in the cache. */
105 static htab_t gdb_bfd_cache
;
107 /* The type of an object being looked up in gdb_bfd_cache. We use
108 htab's capability of storing one kind of object (BFD in this case)
109 and using a different sort of object for searching. */
111 struct gdb_bfd_cache_search
114 const char *filename
;
119 /* A hash function for BFDs. */
122 hash_bfd (const void *b
)
126 /* It is simplest to just hash the filename. */
127 return htab_hash_string (bfd_get_filename (abfd
));
130 /* An equality function for BFDs. Note that this expects the caller
131 to search using struct gdb_bfd_cache_search only, not BFDs. */
134 eq_bfd (const void *a
, const void *b
)
137 const struct gdb_bfd_cache_search
*s
= b
;
138 struct gdb_bfd_data
*gdata
= bfd_usrdata (abfd
);
140 return (gdata
->mtime
== s
->mtime
141 && strcmp (bfd_get_filename (abfd
), s
->filename
) == 0);
147 gdb_bfd_open (const char *name
, const char *target
, int fd
)
152 struct gdb_bfd_cache_search search
;
155 if (gdb_bfd_cache
== NULL
)
156 gdb_bfd_cache
= htab_create_alloc (1, hash_bfd
, eq_bfd
, NULL
,
161 fd
= open (name
, O_RDONLY
| O_BINARY
);
164 bfd_set_error (bfd_error_system_call
);
169 search
.filename
= name
;
170 if (fstat (fd
, &st
) < 0)
172 /* Weird situation here. */
176 search
.mtime
= st
.st_mtime
;
178 /* Note that this must compute the same result as hash_bfd. */
179 hash
= htab_hash_string (name
);
180 /* Note that we cannot use htab_find_slot_with_hash here, because
181 opening the BFD may fail; and this would violate hashtab
183 abfd
= htab_find_with_hash (gdb_bfd_cache
, &search
, hash
);
191 abfd
= bfd_fopen (name
, target
, FOPEN_RB
, fd
);
195 slot
= htab_find_slot_with_hash (gdb_bfd_cache
, &search
, hash
, INSERT
);
199 gdb_bfd_stash_filename (abfd
);
204 /* A helper function that releases any section data attached to the
208 free_one_bfd_section (bfd
*abfd
, asection
*sectp
, void *ignore
)
210 struct gdb_bfd_section_data
*sect
= bfd_get_section_userdata (abfd
, sectp
);
212 if (sect
!= NULL
&& sect
->data
!= NULL
)
215 if (sect
->map_addr
!= NULL
)
219 res
= munmap (sect
->map_addr
, sect
->map_len
);
220 gdb_assert (res
== 0);
228 /* Close ABFD, and warn if that fails. */
231 gdb_bfd_close_or_warn (struct bfd
*abfd
)
234 char *name
= bfd_get_filename (abfd
);
236 bfd_map_over_sections (abfd
, free_one_bfd_section
, NULL
);
238 ret
= bfd_close (abfd
);
241 warning (_("cannot close \"%s\": %s"),
242 name
, bfd_errmsg (bfd_get_error ()));
250 gdb_bfd_ref (struct bfd
*abfd
)
252 struct gdb_bfd_data
*gdata
;
258 gdata
= bfd_usrdata (abfd
);
266 /* Ask BFD to decompress sections in bfd_get_full_section_contents. */
267 abfd
->flags
|= BFD_DECOMPRESS
;
269 gdata
= bfd_zalloc (abfd
, sizeof (struct gdb_bfd_data
));
271 gdata
->mtime
= bfd_get_mtime (abfd
);
272 gdata
->archive_bfd
= NULL
;
273 bfd_usrdata (abfd
) = gdata
;
275 bfd_alloc_data (abfd
);
277 /* This is the first we've seen it, so add it to the hash table. */
278 slot
= htab_find_slot (all_bfds
, abfd
, INSERT
);
279 gdb_assert (slot
&& !*slot
);
286 gdb_bfd_unref (struct bfd
*abfd
)
288 struct gdb_bfd_data
*gdata
;
289 struct gdb_bfd_cache_search search
;
295 gdata
= bfd_usrdata (abfd
);
296 gdb_assert (gdata
->refc
>= 1);
302 archive_bfd
= gdata
->archive_bfd
;
303 search
.filename
= bfd_get_filename (abfd
);
305 if (gdb_bfd_cache
&& search
.filename
)
307 hashval_t hash
= htab_hash_string (search
.filename
);
310 search
.mtime
= gdata
->mtime
;
311 slot
= htab_find_slot_with_hash (gdb_bfd_cache
, &search
, hash
,
315 htab_clear_slot (gdb_bfd_cache
, slot
);
318 bfd_free_data (abfd
);
319 bfd_usrdata (abfd
) = NULL
; /* Paranoia. */
321 htab_remove_elt (all_bfds
, abfd
);
323 gdb_bfd_close_or_warn (abfd
);
325 gdb_bfd_unref (archive_bfd
);
328 /* A helper function that returns the section data descriptor
329 associated with SECTION. If no such descriptor exists, a new one
330 is allocated and cleared. */
332 static struct gdb_bfd_section_data
*
333 get_section_descriptor (asection
*section
)
335 struct gdb_bfd_section_data
*result
;
337 result
= bfd_get_section_userdata (section
->owner
, section
);
341 result
= bfd_zalloc (section
->owner
, sizeof (*result
));
342 bfd_set_section_userdata (section
->owner
, section
, result
);
351 gdb_bfd_map_section (asection
*sectp
, bfd_size_type
*size
)
354 struct gdb_bfd_section_data
*descriptor
;
357 gdb_assert ((sectp
->flags
& SEC_RELOC
) == 0);
358 gdb_assert (size
!= NULL
);
362 descriptor
= get_section_descriptor (sectp
);
364 /* If the data was already read for this BFD, just reuse it. */
365 if (descriptor
->data
!= NULL
)
369 if (!bfd_is_section_compressed (abfd
, sectp
))
371 /* The page size, used when mmapping. */
375 pagesize
= getpagesize ();
377 /* Only try to mmap sections which are large enough: we don't want
378 to waste space due to fragmentation. */
380 if (bfd_get_section_size (sectp
) > 4 * pagesize
)
382 descriptor
->size
= bfd_get_section_size (sectp
);
383 descriptor
->data
= bfd_mmap (abfd
, 0, descriptor
->size
, PROT_READ
,
384 MAP_PRIVATE
, sectp
->filepos
,
385 &descriptor
->map_addr
,
386 &descriptor
->map_len
);
388 if ((caddr_t
)descriptor
->data
!= MAP_FAILED
)
390 #if HAVE_POSIX_MADVISE
391 posix_madvise (descriptor
->map_addr
, descriptor
->map_len
,
392 POSIX_MADV_WILLNEED
);
397 /* On failure, clear out the section data and try again. */
398 memset (descriptor
, 0, sizeof (*descriptor
));
401 #endif /* HAVE_MMAP */
403 /* Handle compressed sections, or ordinary uncompressed sections in
406 descriptor
->size
= bfd_get_section_size (sectp
);
407 descriptor
->data
= NULL
;
410 if (!bfd_get_full_section_contents (abfd
, sectp
, &data
))
411 error (_("Can't read data for section '%s' in file '%s'"),
412 bfd_get_section_name (abfd
, sectp
),
413 bfd_get_filename (abfd
));
414 descriptor
->data
= data
;
417 gdb_assert (descriptor
->data
!= NULL
);
418 *size
= descriptor
->size
;
419 return descriptor
->data
;
422 /* Return 32-bit CRC for ABFD. If successful store it to *FILE_CRC_RETURN and
423 return 1. Otherwise print a warning and return 0. ABFD seek position is
427 get_file_crc (bfd
*abfd
, unsigned long *file_crc_return
)
429 unsigned long file_crc
= 0;
431 if (bfd_seek (abfd
, 0, SEEK_SET
) != 0)
433 warning (_("Problem reading \"%s\" for CRC: %s"),
434 bfd_get_filename (abfd
), bfd_errmsg (bfd_get_error ()));
440 gdb_byte buffer
[8 * 1024];
443 count
= bfd_bread (buffer
, sizeof (buffer
), abfd
);
444 if (count
== (bfd_size_type
) -1)
446 warning (_("Problem reading \"%s\" for CRC: %s"),
447 bfd_get_filename (abfd
), bfd_errmsg (bfd_get_error ()));
452 file_crc
= bfd_calc_gnu_debuglink_crc32 (file_crc
, buffer
, count
);
455 *file_crc_return
= file_crc
;
462 gdb_bfd_crc (struct bfd
*abfd
, unsigned long *crc_out
)
464 struct gdb_bfd_data
*gdata
= bfd_usrdata (abfd
);
466 if (!gdata
->crc_computed
)
467 gdata
->crc_computed
= get_file_crc (abfd
, &gdata
->crc
);
469 if (gdata
->crc_computed
)
470 *crc_out
= gdata
->crc
;
471 return gdata
->crc_computed
;
479 gdb_bfd_fopen (const char *filename
, const char *target
, const char *mode
,
482 bfd
*result
= bfd_fopen (filename
, target
, mode
, fd
);
486 gdb_bfd_stash_filename (result
);
487 gdb_bfd_ref (result
);
496 gdb_bfd_openr (const char *filename
, const char *target
)
498 bfd
*result
= bfd_openr (filename
, target
);
502 gdb_bfd_stash_filename (result
);
503 gdb_bfd_ref (result
);
512 gdb_bfd_openw (const char *filename
, const char *target
)
514 bfd
*result
= bfd_openw (filename
, target
);
518 gdb_bfd_stash_filename (result
);
519 gdb_bfd_ref (result
);
528 gdb_bfd_openr_iovec (const char *filename
, const char *target
,
529 void *(*open_func
) (struct bfd
*nbfd
,
532 file_ptr (*pread_func
) (struct bfd
*nbfd
,
537 int (*close_func
) (struct bfd
*nbfd
,
539 int (*stat_func
) (struct bfd
*abfd
,
543 bfd
*result
= bfd_openr_iovec (filename
, target
,
544 open_func
, open_closure
,
545 pread_func
, close_func
, stat_func
);
549 gdb_bfd_ref (result
);
550 gdb_bfd_stash_filename (result
);
559 gdb_bfd_mark_parent (bfd
*child
, bfd
*parent
)
561 struct gdb_bfd_data
*gdata
;
564 /* No need to stash the filename here, because we also keep a
565 reference on the parent archive. */
567 gdata
= bfd_usrdata (child
);
568 if (gdata
->archive_bfd
== NULL
)
570 gdata
->archive_bfd
= parent
;
571 gdb_bfd_ref (parent
);
574 gdb_assert (gdata
->archive_bfd
== parent
);
580 gdb_bfd_openr_next_archived_file (bfd
*archive
, bfd
*previous
)
582 bfd
*result
= bfd_openr_next_archived_file (archive
, previous
);
585 gdb_bfd_mark_parent (result
, archive
);
593 gdb_bfd_fdopenr (const char *filename
, const char *target
, int fd
)
595 bfd
*result
= bfd_fdopenr (filename
, target
, fd
);
599 gdb_bfd_ref (result
);
600 gdb_bfd_stash_filename (result
);
608 gdb_static_assert (ARRAY_SIZE (_bfd_std_section
) == 4);
613 gdb_bfd_section_index (bfd
*abfd
, asection
*section
)
617 else if (section
== bfd_com_section_ptr
)
618 return bfd_count_sections (abfd
) + 1;
619 else if (section
== bfd_und_section_ptr
)
620 return bfd_count_sections (abfd
) + 2;
621 else if (section
== bfd_abs_section_ptr
)
622 return bfd_count_sections (abfd
) + 3;
623 else if (section
== bfd_ind_section_ptr
)
624 return bfd_count_sections (abfd
) + 4;
625 return section
->index
;
631 gdb_bfd_count_sections (bfd
*abfd
)
633 return bfd_count_sections (abfd
) + 4;
638 /* A callback for htab_traverse that prints a single BFD. */
641 print_one_bfd (void **slot
, void *data
)
644 struct gdb_bfd_data
*gdata
= bfd_usrdata (abfd
);
645 struct ui_out
*uiout
= data
;
646 struct cleanup
*inner
;
648 inner
= make_cleanup_ui_out_tuple_begin_end (uiout
, NULL
);
649 ui_out_field_int (uiout
, "refcount", gdata
->refc
);
650 ui_out_field_string (uiout
, "addr", host_address_to_string (abfd
));
651 ui_out_field_string (uiout
, "filename", bfd_get_filename (abfd
));
652 ui_out_text (uiout
, "\n");
658 /* Implement the 'maint info bfd' command. */
661 maintenance_info_bfds (char *arg
, int from_tty
)
663 struct cleanup
*cleanup
;
664 struct ui_out
*uiout
= current_uiout
;
666 cleanup
= make_cleanup_ui_out_table_begin_end (uiout
, 3, -1, "bfds");
667 ui_out_table_header (uiout
, 10, ui_left
, "refcount", "Refcount");
668 ui_out_table_header (uiout
, 18, ui_left
, "addr", "Address");
669 ui_out_table_header (uiout
, 40, ui_left
, "filename", "Filename");
671 ui_out_table_body (uiout
);
672 htab_traverse (all_bfds
, print_one_bfd
, uiout
);
674 do_cleanups (cleanup
);
677 /* -Wmissing-prototypes */
678 extern initialize_file_ftype _initialize_gdb_bfd
;
681 _initialize_gdb_bfd (void)
683 all_bfds
= htab_create_alloc (10, htab_hash_pointer
, htab_eq_pointer
,
684 NULL
, xcalloc
, xfree
);
686 add_cmd ("bfds", class_maintenance
, maintenance_info_bfds
, _("\
687 List the BFDs that are currently open."),
688 &maintenanceinfolist
);