1 /* Definitions for BFD wrappers used by GDB.
3 Copyright (C) 2011-2015 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/>. */
25 #include "filestuff.h"
30 #define MAP_FAILED ((void *) -1)
34 #include "gdb/fileio.h"
39 /* An object of this type is stored in the section's user data when
42 struct gdb_bfd_section_data
44 /* Size of the data. */
46 /* If the data was mmapped, this is the length of the map. */
47 bfd_size_type map_len
;
48 /* The data. If NULL, the section data has not been read. */
50 /* If the data was mmapped, this is the map address. */
54 /* A hash table holding every BFD that gdb knows about. This is not
55 to be confused with 'gdb_bfd_cache', which is used for sharing
56 BFDs; in contrast, this hash is used just to implement
59 static htab_t all_bfds
;
61 /* An object of this type is stored in each BFD's user data. */
65 /* The reference count. */
68 /* The mtime of the BFD at the point the cache entry was made. */
71 /* This is true if we have determined whether this BFD has any
72 sections requiring relocation. */
73 unsigned int relocation_computed
: 1;
75 /* This is true if any section needs relocation. */
76 unsigned int needs_relocations
: 1;
78 /* This is true if we have successfully computed the file's CRC. */
79 unsigned int crc_computed
: 1;
84 /* If the BFD comes from an archive, this points to the archive's
85 BFD. Otherwise, this is NULL. */
88 /* Table of all the bfds this bfd has included. */
89 VEC (bfdp
) *included_bfds
;
95 #define GDB_BFD_DATA_ACCESSOR(ABFD) \
96 ((struct gdb_bfd_data *) bfd_usrdata (ABFD))
98 DEFINE_REGISTRY (bfd
, GDB_BFD_DATA_ACCESSOR
)
100 /* A hash table storing all the BFDs maintained in the cache. */
102 static htab_t gdb_bfd_cache
;
104 /* The type of an object being looked up in gdb_bfd_cache. We use
105 htab's capability of storing one kind of object (BFD in this case)
106 and using a different sort of object for searching. */
108 struct gdb_bfd_cache_search
111 const char *filename
;
116 /* A hash function for BFDs. */
119 hash_bfd (const void *b
)
123 /* It is simplest to just hash the filename. */
124 return htab_hash_string (bfd_get_filename (abfd
));
127 /* An equality function for BFDs. Note that this expects the caller
128 to search using struct gdb_bfd_cache_search only, not BFDs. */
131 eq_bfd (const void *a
, const void *b
)
134 const struct gdb_bfd_cache_search
*s
= b
;
135 struct gdb_bfd_data
*gdata
= bfd_usrdata (abfd
);
137 return (gdata
->mtime
== s
->mtime
138 && strcmp (bfd_get_filename (abfd
), s
->filename
) == 0);
144 is_target_filename (const char *name
)
146 return startswith (name
, TARGET_SYSROOT_PREFIX
);
152 gdb_bfd_has_target_filename (struct bfd
*abfd
)
154 return is_target_filename (bfd_get_filename (abfd
));
158 /* Return the system error number corresponding to ERRNUM. */
161 fileio_errno_to_host (int errnum
)
205 case FILEIO_ENAMETOOLONG
:
211 /* Wrapper for target_fileio_open suitable for passing as the
212 OPEN_FUNC argument to gdb_bfd_openr_iovec. The supplied
213 OPEN_CLOSURE is unused. */
216 gdb_bfd_iovec_fileio_open (struct bfd
*abfd
, void *open_closure
)
218 const char *filename
= bfd_get_filename (abfd
);
219 int fd
, target_errno
;
222 gdb_assert (is_target_filename (filename
));
224 fd
= target_fileio_open (filename
+ strlen (TARGET_SYSROOT_PREFIX
),
229 errno
= fileio_errno_to_host (target_errno
);
230 bfd_set_error (bfd_error_system_call
);
234 stream
= XCNEW (int);
239 /* Wrapper for target_fileio_pread suitable for passing as the
240 PREAD_FUNC argument to gdb_bfd_openr_iovec. */
243 gdb_bfd_iovec_fileio_pread (struct bfd
*abfd
, void *stream
, void *buf
,
244 file_ptr nbytes
, file_ptr offset
)
246 int fd
= *(int *) stream
;
253 bytes
= target_fileio_pread (fd
, (gdb_byte
*) buf
+ pos
,
254 nbytes
- pos
, offset
+ pos
,
257 /* Success, but no bytes, means end-of-file. */
261 errno
= fileio_errno_to_host (target_errno
);
262 bfd_set_error (bfd_error_system_call
);
272 /* Wrapper for target_fileio_close suitable for passing as the
273 CLOSE_FUNC argument to gdb_bfd_openr_iovec. */
276 gdb_bfd_iovec_fileio_close (struct bfd
*abfd
, void *stream
)
278 int fd
= *(int *) stream
;
283 /* Ignore errors on close. These may happen with remote
284 targets if the connection has already been torn down. */
285 target_fileio_close (fd
, &target_errno
);
287 /* Zero means success. */
291 /* Wrapper for target_fileio_fstat suitable for passing as the
292 STAT_FUNC argument to gdb_bfd_openr_iovec. */
295 gdb_bfd_iovec_fileio_fstat (struct bfd
*abfd
, void *stream
,
298 int fd
= *(int *) stream
;
302 result
= target_fileio_fstat (fd
, sb
, &target_errno
);
305 errno
= fileio_errno_to_host (target_errno
);
306 bfd_set_error (bfd_error_system_call
);
315 gdb_bfd_open (const char *name
, const char *target
, int fd
)
320 struct gdb_bfd_cache_search search
;
323 if (is_target_filename (name
))
325 if (!target_filesystem_is_local ())
327 gdb_assert (fd
== -1);
329 abfd
= gdb_bfd_openr_iovec (name
, target
,
330 gdb_bfd_iovec_fileio_open
, NULL
,
331 gdb_bfd_iovec_fileio_pread
,
332 gdb_bfd_iovec_fileio_close
,
333 gdb_bfd_iovec_fileio_fstat
);
335 if (abfd
!= NULL
|| errno
!= ENOSYS
)
338 /* gdb_bfd_iovec_fileio_open failed with ENOSYS. This can
339 happen, for example, with vgdb (Valgrind GDB), which
340 presents itself as a remote target but works on the local
341 filesystem: it does not implement remote get and users
342 are not expected to set gdb_sysroot. To handle this case
343 we fall back to trying the local filesystem iff
344 gdb_sysroot is exactly TARGET_SYSROOT_PREFIX. */
345 if (gdb_sysroot
== NULL
346 || strcmp (gdb_sysroot
, TARGET_SYSROOT_PREFIX
) != 0)
350 name
+= strlen (TARGET_SYSROOT_PREFIX
);
353 if (gdb_bfd_cache
== NULL
)
354 gdb_bfd_cache
= htab_create_alloc (1, hash_bfd
, eq_bfd
, NULL
,
359 fd
= gdb_open_cloexec (name
, O_RDONLY
| O_BINARY
, 0);
362 bfd_set_error (bfd_error_system_call
);
367 search
.filename
= name
;
368 if (fstat (fd
, &st
) < 0)
370 /* Weird situation here. */
374 search
.mtime
= st
.st_mtime
;
376 /* Note that this must compute the same result as hash_bfd. */
377 hash
= htab_hash_string (name
);
378 /* Note that we cannot use htab_find_slot_with_hash here, because
379 opening the BFD may fail; and this would violate hashtab
381 abfd
= htab_find_with_hash (gdb_bfd_cache
, &search
, hash
);
389 abfd
= bfd_fopen (name
, target
, FOPEN_RB
, fd
);
393 slot
= htab_find_slot_with_hash (gdb_bfd_cache
, &search
, hash
, INSERT
);
401 /* A helper function that releases any section data attached to the
405 free_one_bfd_section (bfd
*abfd
, asection
*sectp
, void *ignore
)
407 struct gdb_bfd_section_data
*sect
= bfd_get_section_userdata (abfd
, sectp
);
409 if (sect
!= NULL
&& sect
->data
!= NULL
)
412 if (sect
->map_addr
!= NULL
)
416 res
= munmap (sect
->map_addr
, sect
->map_len
);
417 gdb_assert (res
== 0);
425 /* Close ABFD, and warn if that fails. */
428 gdb_bfd_close_or_warn (struct bfd
*abfd
)
431 char *name
= bfd_get_filename (abfd
);
433 bfd_map_over_sections (abfd
, free_one_bfd_section
, NULL
);
435 ret
= bfd_close (abfd
);
438 warning (_("cannot close \"%s\": %s"),
439 name
, bfd_errmsg (bfd_get_error ()));
447 gdb_bfd_ref (struct bfd
*abfd
)
449 struct gdb_bfd_data
*gdata
;
455 gdata
= bfd_usrdata (abfd
);
463 /* Ask BFD to decompress sections in bfd_get_full_section_contents. */
464 abfd
->flags
|= BFD_DECOMPRESS
;
466 gdata
= bfd_zalloc (abfd
, sizeof (struct gdb_bfd_data
));
468 gdata
->mtime
= bfd_get_mtime (abfd
);
469 gdata
->archive_bfd
= NULL
;
470 bfd_usrdata (abfd
) = gdata
;
472 bfd_alloc_data (abfd
);
474 /* This is the first we've seen it, so add it to the hash table. */
475 slot
= htab_find_slot (all_bfds
, abfd
, INSERT
);
476 gdb_assert (slot
&& !*slot
);
483 gdb_bfd_unref (struct bfd
*abfd
)
486 struct gdb_bfd_data
*gdata
;
487 struct gdb_bfd_cache_search search
;
488 bfd
*archive_bfd
, *included_bfd
;
493 gdata
= bfd_usrdata (abfd
);
494 gdb_assert (gdata
->refc
>= 1);
500 archive_bfd
= gdata
->archive_bfd
;
501 search
.filename
= bfd_get_filename (abfd
);
503 if (gdb_bfd_cache
&& search
.filename
)
505 hashval_t hash
= htab_hash_string (search
.filename
);
508 search
.mtime
= gdata
->mtime
;
509 slot
= htab_find_slot_with_hash (gdb_bfd_cache
, &search
, hash
,
513 htab_clear_slot (gdb_bfd_cache
, slot
);
517 VEC_iterate (bfdp
, gdata
->included_bfds
, ix
, included_bfd
);
519 gdb_bfd_unref (included_bfd
);
520 VEC_free (bfdp
, gdata
->included_bfds
);
522 bfd_free_data (abfd
);
523 bfd_usrdata (abfd
) = NULL
; /* Paranoia. */
525 htab_remove_elt (all_bfds
, abfd
);
527 gdb_bfd_close_or_warn (abfd
);
529 gdb_bfd_unref (archive_bfd
);
532 /* A helper function that returns the section data descriptor
533 associated with SECTION. If no such descriptor exists, a new one
534 is allocated and cleared. */
536 static struct gdb_bfd_section_data
*
537 get_section_descriptor (asection
*section
)
539 struct gdb_bfd_section_data
*result
;
541 result
= bfd_get_section_userdata (section
->owner
, section
);
545 result
= bfd_zalloc (section
->owner
, sizeof (*result
));
546 bfd_set_section_userdata (section
->owner
, section
, result
);
555 gdb_bfd_map_section (asection
*sectp
, bfd_size_type
*size
)
558 struct gdb_bfd_section_data
*descriptor
;
561 gdb_assert ((sectp
->flags
& SEC_RELOC
) == 0);
562 gdb_assert (size
!= NULL
);
566 descriptor
= get_section_descriptor (sectp
);
568 /* If the data was already read for this BFD, just reuse it. */
569 if (descriptor
->data
!= NULL
)
573 if (!bfd_is_section_compressed (abfd
, sectp
))
575 /* The page size, used when mmapping. */
579 pagesize
= getpagesize ();
581 /* Only try to mmap sections which are large enough: we don't want
582 to waste space due to fragmentation. */
584 if (bfd_get_section_size (sectp
) > 4 * pagesize
)
586 descriptor
->size
= bfd_get_section_size (sectp
);
587 descriptor
->data
= bfd_mmap (abfd
, 0, descriptor
->size
, PROT_READ
,
588 MAP_PRIVATE
, sectp
->filepos
,
589 &descriptor
->map_addr
,
590 &descriptor
->map_len
);
592 if ((caddr_t
)descriptor
->data
!= MAP_FAILED
)
594 #if HAVE_POSIX_MADVISE
595 posix_madvise (descriptor
->map_addr
, descriptor
->map_len
,
596 POSIX_MADV_WILLNEED
);
601 /* On failure, clear out the section data and try again. */
602 memset (descriptor
, 0, sizeof (*descriptor
));
605 #endif /* HAVE_MMAP */
607 /* Handle compressed sections, or ordinary uncompressed sections in
610 descriptor
->size
= bfd_get_section_size (sectp
);
611 descriptor
->data
= NULL
;
614 if (!bfd_get_full_section_contents (abfd
, sectp
, &data
))
615 error (_("Can't read data for section '%s' in file '%s'"),
616 bfd_get_section_name (abfd
, sectp
),
617 bfd_get_filename (abfd
));
618 descriptor
->data
= data
;
621 gdb_assert (descriptor
->data
!= NULL
);
622 *size
= descriptor
->size
;
623 return descriptor
->data
;
626 /* Return 32-bit CRC for ABFD. If successful store it to *FILE_CRC_RETURN and
627 return 1. Otherwise print a warning and return 0. ABFD seek position is
631 get_file_crc (bfd
*abfd
, unsigned long *file_crc_return
)
633 unsigned long file_crc
= 0;
635 if (bfd_seek (abfd
, 0, SEEK_SET
) != 0)
637 warning (_("Problem reading \"%s\" for CRC: %s"),
638 bfd_get_filename (abfd
), bfd_errmsg (bfd_get_error ()));
644 gdb_byte buffer
[8 * 1024];
647 count
= bfd_bread (buffer
, sizeof (buffer
), abfd
);
648 if (count
== (bfd_size_type
) -1)
650 warning (_("Problem reading \"%s\" for CRC: %s"),
651 bfd_get_filename (abfd
), bfd_errmsg (bfd_get_error ()));
656 file_crc
= bfd_calc_gnu_debuglink_crc32 (file_crc
, buffer
, count
);
659 *file_crc_return
= file_crc
;
666 gdb_bfd_crc (struct bfd
*abfd
, unsigned long *crc_out
)
668 struct gdb_bfd_data
*gdata
= bfd_usrdata (abfd
);
670 if (!gdata
->crc_computed
)
671 gdata
->crc_computed
= get_file_crc (abfd
, &gdata
->crc
);
673 if (gdata
->crc_computed
)
674 *crc_out
= gdata
->crc
;
675 return gdata
->crc_computed
;
683 gdb_bfd_fopen (const char *filename
, const char *target
, const char *mode
,
686 bfd
*result
= bfd_fopen (filename
, target
, mode
, fd
);
689 gdb_bfd_ref (result
);
697 gdb_bfd_openr (const char *filename
, const char *target
)
699 bfd
*result
= bfd_openr (filename
, target
);
702 gdb_bfd_ref (result
);
710 gdb_bfd_openw (const char *filename
, const char *target
)
712 bfd
*result
= bfd_openw (filename
, target
);
715 gdb_bfd_ref (result
);
723 gdb_bfd_openr_iovec (const char *filename
, const char *target
,
724 void *(*open_func
) (struct bfd
*nbfd
,
727 file_ptr (*pread_func
) (struct bfd
*nbfd
,
732 int (*close_func
) (struct bfd
*nbfd
,
734 int (*stat_func
) (struct bfd
*abfd
,
738 bfd
*result
= bfd_openr_iovec (filename
, target
,
739 open_func
, open_closure
,
740 pread_func
, close_func
, stat_func
);
743 gdb_bfd_ref (result
);
751 gdb_bfd_mark_parent (bfd
*child
, bfd
*parent
)
753 struct gdb_bfd_data
*gdata
;
756 /* No need to stash the filename here, because we also keep a
757 reference on the parent archive. */
759 gdata
= bfd_usrdata (child
);
760 if (gdata
->archive_bfd
== NULL
)
762 gdata
->archive_bfd
= parent
;
763 gdb_bfd_ref (parent
);
766 gdb_assert (gdata
->archive_bfd
== parent
);
772 gdb_bfd_openr_next_archived_file (bfd
*archive
, bfd
*previous
)
774 bfd
*result
= bfd_openr_next_archived_file (archive
, previous
);
777 gdb_bfd_mark_parent (result
, archive
);
785 gdb_bfd_record_inclusion (bfd
*includer
, bfd
*includee
)
787 struct gdb_bfd_data
*gdata
;
789 gdb_bfd_ref (includee
);
790 gdata
= bfd_usrdata (includer
);
791 VEC_safe_push (bfdp
, gdata
->included_bfds
, includee
);
797 gdb_bfd_fdopenr (const char *filename
, const char *target
, int fd
)
799 bfd
*result
= bfd_fdopenr (filename
, target
, fd
);
802 gdb_bfd_ref (result
);
809 gdb_static_assert (ARRAY_SIZE (_bfd_std_section
) == 4);
814 gdb_bfd_section_index (bfd
*abfd
, asection
*section
)
818 else if (section
== bfd_com_section_ptr
)
819 return bfd_count_sections (abfd
);
820 else if (section
== bfd_und_section_ptr
)
821 return bfd_count_sections (abfd
) + 1;
822 else if (section
== bfd_abs_section_ptr
)
823 return bfd_count_sections (abfd
) + 2;
824 else if (section
== bfd_ind_section_ptr
)
825 return bfd_count_sections (abfd
) + 3;
826 return section
->index
;
832 gdb_bfd_count_sections (bfd
*abfd
)
834 return bfd_count_sections (abfd
) + 4;
840 gdb_bfd_requires_relocations (bfd
*abfd
)
842 struct gdb_bfd_data
*gdata
= bfd_usrdata (abfd
);
844 if (gdata
->relocation_computed
== 0)
848 for (sect
= abfd
->sections
; sect
!= NULL
; sect
= sect
->next
)
849 if ((sect
->flags
& SEC_RELOC
) != 0)
851 gdata
->needs_relocations
= 1;
855 gdata
->relocation_computed
= 1;
858 return gdata
->needs_relocations
;
863 /* A callback for htab_traverse that prints a single BFD. */
866 print_one_bfd (void **slot
, void *data
)
869 struct gdb_bfd_data
*gdata
= bfd_usrdata (abfd
);
870 struct ui_out
*uiout
= data
;
871 struct cleanup
*inner
;
873 inner
= make_cleanup_ui_out_tuple_begin_end (uiout
, NULL
);
874 ui_out_field_int (uiout
, "refcount", gdata
->refc
);
875 ui_out_field_string (uiout
, "addr", host_address_to_string (abfd
));
876 ui_out_field_string (uiout
, "filename", bfd_get_filename (abfd
));
877 ui_out_text (uiout
, "\n");
883 /* Implement the 'maint info bfd' command. */
886 maintenance_info_bfds (char *arg
, int from_tty
)
888 struct cleanup
*cleanup
;
889 struct ui_out
*uiout
= current_uiout
;
891 cleanup
= make_cleanup_ui_out_table_begin_end (uiout
, 3, -1, "bfds");
892 ui_out_table_header (uiout
, 10, ui_left
, "refcount", "Refcount");
893 ui_out_table_header (uiout
, 18, ui_left
, "addr", "Address");
894 ui_out_table_header (uiout
, 40, ui_left
, "filename", "Filename");
896 ui_out_table_body (uiout
);
897 htab_traverse (all_bfds
, print_one_bfd
, uiout
);
899 do_cleanups (cleanup
);
902 /* -Wmissing-prototypes */
903 extern initialize_file_ftype _initialize_gdb_bfd
;
906 _initialize_gdb_bfd (void)
908 all_bfds
= htab_create_alloc (10, htab_hash_pointer
, htab_eq_pointer
,
909 NULL
, xcalloc
, xfree
);
911 add_cmd ("bfds", class_maintenance
, maintenance_info_bfds
, _("\
912 List the BFDs that are currently open."),
913 &maintenanceinfolist
);