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"
40 /* An object of this type is stored in the section's user data when
43 struct gdb_bfd_section_data
45 /* Size of the data. */
47 /* If the data was mmapped, this is the length of the map. */
48 bfd_size_type map_len;
49 /* The data. If NULL, the section data has not been read. */
51 /* If the data was mmapped, this is the map address. */
55 /* A hash table holding every BFD that gdb knows about. This is not
56 to be confused with 'gdb_bfd_cache', which is used for sharing
57 BFDs; in contrast, this hash is used just to implement
60 static htab_t all_bfds;
62 /* An object of this type is stored in each BFD's user data. */
66 /* The reference count. */
69 /* The mtime of the BFD at the point the cache entry was made. */
72 /* The file size (in bytes) at the point the cache entry was made. */
75 /* The inode of the file at the point the cache entry was made. */
78 /* The device id of the file at the point the cache entry was made. */
81 /* This is true if we have determined whether this BFD has any
82 sections requiring relocation. */
83 unsigned int relocation_computed : 1;
85 /* This is true if any section needs relocation. */
86 unsigned int needs_relocations : 1;
88 /* This is true if we have successfully computed the file's CRC. */
89 unsigned int crc_computed : 1;
94 /* If the BFD comes from an archive, this points to the archive's
95 BFD. Otherwise, this is NULL. */
98 /* Table of all the bfds this bfd has included. */
99 VEC (bfdp) *included_bfds;
105 #define GDB_BFD_DATA_ACCESSOR(ABFD) \
106 ((struct gdb_bfd_data *) bfd_usrdata (ABFD))
108 DEFINE_REGISTRY (bfd, GDB_BFD_DATA_ACCESSOR)
110 /* A hash table storing all the BFDs maintained in the cache. */
112 static htab_t gdb_bfd_cache;
114 /* The type of an object being looked up in gdb_bfd_cache. We use
115 htab's capability of storing one kind of object (BFD in this case)
116 and using a different sort of object for searching. */
118 struct gdb_bfd_cache_search
121 const char *filename;
124 /* The file size (in bytes). */
126 /* The inode of the file. */
128 /* The device id of the file. */
132 /* A hash function for BFDs. */
135 hash_bfd (const void *b)
139 /* It is simplest to just hash the filename. */
140 return htab_hash_string (bfd_get_filename (abfd));
143 /* An equality function for BFDs. Note that this expects the caller
144 to search using struct gdb_bfd_cache_search only, not BFDs. */
147 eq_bfd (const void *a, const void *b)
150 const struct gdb_bfd_cache_search *s = b;
151 struct gdb_bfd_data *gdata = bfd_usrdata (abfd);
153 return (gdata->mtime == s->mtime
154 && gdata->size == s->size
155 && gdata->inode == s->inode
156 && gdata->device_id == s->device_id
157 && strcmp (bfd_get_filename (abfd), s->filename) == 0);
163 is_target_filename (const char *name)
165 return startswith (name, TARGET_SYSROOT_PREFIX);
171 gdb_bfd_has_target_filename (struct bfd *abfd)
173 return is_target_filename (bfd_get_filename (abfd));
177 /* Return the system error number corresponding to ERRNUM. */
180 fileio_errno_to_host (int errnum)
224 case FILEIO_ENAMETOOLONG:
230 /* Wrapper for target_fileio_open suitable for passing as the
231 OPEN_FUNC argument to gdb_bfd_openr_iovec. The supplied
232 OPEN_CLOSURE is unused. */
235 gdb_bfd_iovec_fileio_open (struct bfd *abfd, void *inferior)
237 const char *filename = bfd_get_filename (abfd);
238 int fd, target_errno;
241 gdb_assert (is_target_filename (filename));
243 fd = target_fileio_open ((struct inferior *) inferior,
244 filename + strlen (TARGET_SYSROOT_PREFIX),
249 errno = fileio_errno_to_host (target_errno);
250 bfd_set_error (bfd_error_system_call);
254 stream = XCNEW (int);
259 /* Wrapper for target_fileio_pread suitable for passing as the
260 PREAD_FUNC argument to gdb_bfd_openr_iovec. */
263 gdb_bfd_iovec_fileio_pread (struct bfd *abfd, void *stream, void *buf,
264 file_ptr nbytes, file_ptr offset)
266 int fd = *(int *) stream;
273 bytes = target_fileio_pread (fd, (gdb_byte *) buf + pos,
274 nbytes - pos, offset + pos,
277 /* Success, but no bytes, means end-of-file. */
281 errno = fileio_errno_to_host (target_errno);
282 bfd_set_error (bfd_error_system_call);
292 /* Wrapper for target_fileio_close suitable for passing as the
293 CLOSE_FUNC argument to gdb_bfd_openr_iovec. */
296 gdb_bfd_iovec_fileio_close (struct bfd *abfd, void *stream)
298 int fd = *(int *) stream;
303 /* Ignore errors on close. These may happen with remote
304 targets if the connection has already been torn down. */
305 target_fileio_close (fd, &target_errno);
307 /* Zero means success. */
311 /* Wrapper for target_fileio_fstat suitable for passing as the
312 STAT_FUNC argument to gdb_bfd_openr_iovec. */
315 gdb_bfd_iovec_fileio_fstat (struct bfd *abfd, void *stream,
318 int fd = *(int *) stream;
322 result = target_fileio_fstat (fd, sb, &target_errno);
325 errno = fileio_errno_to_host (target_errno);
326 bfd_set_error (bfd_error_system_call);
335 gdb_bfd_open (const char *name, const char *target, int fd)
340 struct gdb_bfd_cache_search search;
343 if (is_target_filename (name))
345 if (!target_filesystem_is_local ())
347 gdb_assert (fd == -1);
349 return gdb_bfd_openr_iovec (name, target,
350 gdb_bfd_iovec_fileio_open,
352 gdb_bfd_iovec_fileio_pread,
353 gdb_bfd_iovec_fileio_close,
354 gdb_bfd_iovec_fileio_fstat);
357 name += strlen (TARGET_SYSROOT_PREFIX);
360 if (gdb_bfd_cache == NULL)
361 gdb_bfd_cache = htab_create_alloc (1, hash_bfd, eq_bfd, NULL,
366 fd = gdb_open_cloexec (name, O_RDONLY | O_BINARY, 0);
369 bfd_set_error (bfd_error_system_call);
374 search.filename = name;
375 if (fstat (fd, &st) < 0)
377 /* Weird situation here. */
381 search.device_id = 0;
385 search.mtime = st.st_mtime;
386 search.size = st.st_size;
387 search.inode = st.st_ino;
388 search.device_id = st.st_dev;
391 /* Note that this must compute the same result as hash_bfd. */
392 hash = htab_hash_string (name);
393 /* Note that we cannot use htab_find_slot_with_hash here, because
394 opening the BFD may fail; and this would violate hashtab
396 abfd = htab_find_with_hash (gdb_bfd_cache, &search, hash);
404 abfd = bfd_fopen (name, target, FOPEN_RB, fd);
408 slot = htab_find_slot_with_hash (gdb_bfd_cache, &search, hash, INSERT);
416 /* A helper function that releases any section data attached to the
420 free_one_bfd_section (bfd *abfd, asection *sectp, void *ignore)
422 struct gdb_bfd_section_data *sect = bfd_get_section_userdata (abfd, sectp);
424 if (sect != NULL && sect->data != NULL)
427 if (sect->map_addr != NULL)
431 res = munmap (sect->map_addr, sect->map_len);
432 gdb_assert (res == 0);
440 /* Close ABFD, and warn if that fails. */
443 gdb_bfd_close_or_warn (struct bfd *abfd)
446 char *name = bfd_get_filename (abfd);
448 bfd_map_over_sections (abfd, free_one_bfd_section, NULL);
450 ret = bfd_close (abfd);
453 warning (_("cannot close \"%s\": %s"),
454 name, bfd_errmsg (bfd_get_error ()));
462 gdb_bfd_ref (struct bfd *abfd)
465 struct gdb_bfd_data *gdata;
471 gdata = bfd_usrdata (abfd);
479 /* Ask BFD to decompress sections in bfd_get_full_section_contents. */
480 abfd->flags |= BFD_DECOMPRESS;
482 gdata = bfd_zalloc (abfd, sizeof (struct gdb_bfd_data));
484 gdata->mtime = bfd_get_mtime (abfd);
485 gdata->size = bfd_get_size (abfd);
486 gdata->archive_bfd = NULL;
487 if (bfd_stat (abfd, &buf) == 0)
489 gdata->inode = buf.st_ino;
490 gdata->device_id = buf.st_dev;
494 /* The stat failed. */
496 gdata->device_id = 0;
498 bfd_usrdata (abfd) = gdata;
500 bfd_alloc_data (abfd);
502 /* This is the first we've seen it, so add it to the hash table. */
503 slot = htab_find_slot (all_bfds, abfd, INSERT);
504 gdb_assert (slot && !*slot);
511 gdb_bfd_unref (struct bfd *abfd)
514 struct gdb_bfd_data *gdata;
515 struct gdb_bfd_cache_search search;
516 bfd *archive_bfd, *included_bfd;
521 gdata = bfd_usrdata (abfd);
522 gdb_assert (gdata->refc >= 1);
528 archive_bfd = gdata->archive_bfd;
529 search.filename = bfd_get_filename (abfd);
531 if (gdb_bfd_cache && search.filename)
533 hashval_t hash = htab_hash_string (search.filename);
536 search.mtime = gdata->mtime;
537 search.size = gdata->size;
538 search.inode = gdata->inode;
539 search.device_id = gdata->device_id;
540 slot = htab_find_slot_with_hash (gdb_bfd_cache, &search, hash,
544 htab_clear_slot (gdb_bfd_cache, slot);
548 VEC_iterate (bfdp, gdata->included_bfds, ix, included_bfd);
550 gdb_bfd_unref (included_bfd);
551 VEC_free (bfdp, gdata->included_bfds);
553 bfd_free_data (abfd);
554 bfd_usrdata (abfd) = NULL; /* Paranoia. */
556 htab_remove_elt (all_bfds, abfd);
558 gdb_bfd_close_or_warn (abfd);
560 gdb_bfd_unref (archive_bfd);
563 /* A helper function that returns the section data descriptor
564 associated with SECTION. If no such descriptor exists, a new one
565 is allocated and cleared. */
567 static struct gdb_bfd_section_data *
568 get_section_descriptor (asection *section)
570 struct gdb_bfd_section_data *result;
572 result = bfd_get_section_userdata (section->owner, section);
576 result = bfd_zalloc (section->owner, sizeof (*result));
577 bfd_set_section_userdata (section->owner, section, result);
586 gdb_bfd_map_section (asection *sectp, bfd_size_type *size)
589 struct gdb_bfd_section_data *descriptor;
592 gdb_assert ((sectp->flags & SEC_RELOC) == 0);
593 gdb_assert (size != NULL);
597 descriptor = get_section_descriptor (sectp);
599 /* If the data was already read for this BFD, just reuse it. */
600 if (descriptor->data != NULL)
604 if (!bfd_is_section_compressed (abfd, sectp))
606 /* The page size, used when mmapping. */
610 pagesize = getpagesize ();
612 /* Only try to mmap sections which are large enough: we don't want
613 to waste space due to fragmentation. */
615 if (bfd_get_section_size (sectp) > 4 * pagesize)
617 descriptor->size = bfd_get_section_size (sectp);
618 descriptor->data = bfd_mmap (abfd, 0, descriptor->size, PROT_READ,
619 MAP_PRIVATE, sectp->filepos,
620 &descriptor->map_addr,
621 &descriptor->map_len);
623 if ((caddr_t)descriptor->data != MAP_FAILED)
625 #if HAVE_POSIX_MADVISE
626 posix_madvise (descriptor->map_addr, descriptor->map_len,
627 POSIX_MADV_WILLNEED);
632 /* On failure, clear out the section data and try again. */
633 memset (descriptor, 0, sizeof (*descriptor));
636 #endif /* HAVE_MMAP */
638 /* Handle compressed sections, or ordinary uncompressed sections in
641 descriptor->size = bfd_get_section_size (sectp);
642 descriptor->data = NULL;
645 if (!bfd_get_full_section_contents (abfd, sectp, &data))
646 error (_("Can't read data for section '%s' in file '%s'"),
647 bfd_get_section_name (abfd, sectp),
648 bfd_get_filename (abfd));
649 descriptor->data = data;
652 gdb_assert (descriptor->data != NULL);
653 *size = descriptor->size;
654 return descriptor->data;
657 /* Return 32-bit CRC for ABFD. If successful store it to *FILE_CRC_RETURN and
658 return 1. Otherwise print a warning and return 0. ABFD seek position is
662 get_file_crc (bfd *abfd, unsigned long *file_crc_return)
664 unsigned long file_crc = 0;
666 if (bfd_seek (abfd, 0, SEEK_SET) != 0)
668 warning (_("Problem reading \"%s\" for CRC: %s"),
669 bfd_get_filename (abfd), bfd_errmsg (bfd_get_error ()));
675 gdb_byte buffer[8 * 1024];
678 count = bfd_bread (buffer, sizeof (buffer), abfd);
679 if (count == (bfd_size_type) -1)
681 warning (_("Problem reading \"%s\" for CRC: %s"),
682 bfd_get_filename (abfd), bfd_errmsg (bfd_get_error ()));
687 file_crc = bfd_calc_gnu_debuglink_crc32 (file_crc, buffer, count);
690 *file_crc_return = file_crc;
697 gdb_bfd_crc (struct bfd *abfd, unsigned long *crc_out)
699 struct gdb_bfd_data *gdata = bfd_usrdata (abfd);
701 if (!gdata->crc_computed)
702 gdata->crc_computed = get_file_crc (abfd, &gdata->crc);
704 if (gdata->crc_computed)
705 *crc_out = gdata->crc;
706 return gdata->crc_computed;
714 gdb_bfd_fopen (const char *filename, const char *target, const char *mode,
717 bfd *result = bfd_fopen (filename, target, mode, fd);
720 gdb_bfd_ref (result);
728 gdb_bfd_openr (const char *filename, const char *target)
730 bfd *result = bfd_openr (filename, target);
733 gdb_bfd_ref (result);
741 gdb_bfd_openw (const char *filename, const char *target)
743 bfd *result = bfd_openw (filename, target);
746 gdb_bfd_ref (result);
754 gdb_bfd_openr_iovec (const char *filename, const char *target,
755 void *(*open_func) (struct bfd *nbfd,
758 file_ptr (*pread_func) (struct bfd *nbfd,
763 int (*close_func) (struct bfd *nbfd,
765 int (*stat_func) (struct bfd *abfd,
769 bfd *result = bfd_openr_iovec (filename, target,
770 open_func, open_closure,
771 pread_func, close_func, stat_func);
774 gdb_bfd_ref (result);
782 gdb_bfd_mark_parent (bfd *child, bfd *parent)
784 struct gdb_bfd_data *gdata;
787 /* No need to stash the filename here, because we also keep a
788 reference on the parent archive. */
790 gdata = bfd_usrdata (child);
791 if (gdata->archive_bfd == NULL)
793 gdata->archive_bfd = parent;
794 gdb_bfd_ref (parent);
797 gdb_assert (gdata->archive_bfd == parent);
803 gdb_bfd_openr_next_archived_file (bfd *archive, bfd *previous)
805 bfd *result = bfd_openr_next_archived_file (archive, previous);
808 gdb_bfd_mark_parent (result, archive);
816 gdb_bfd_record_inclusion (bfd *includer, bfd *includee)
818 struct gdb_bfd_data *gdata;
820 gdb_bfd_ref (includee);
821 gdata = bfd_usrdata (includer);
822 VEC_safe_push (bfdp, gdata->included_bfds, includee);
828 gdb_bfd_fdopenr (const char *filename, const char *target, int fd)
830 bfd *result = bfd_fdopenr (filename, target, fd);
833 gdb_bfd_ref (result);
840 gdb_static_assert (ARRAY_SIZE (_bfd_std_section) == 4);
845 gdb_bfd_section_index (bfd *abfd, asection *section)
849 else if (section == bfd_com_section_ptr)
850 return bfd_count_sections (abfd);
851 else if (section == bfd_und_section_ptr)
852 return bfd_count_sections (abfd) + 1;
853 else if (section == bfd_abs_section_ptr)
854 return bfd_count_sections (abfd) + 2;
855 else if (section == bfd_ind_section_ptr)
856 return bfd_count_sections (abfd) + 3;
857 return section->index;
863 gdb_bfd_count_sections (bfd *abfd)
865 return bfd_count_sections (abfd) + 4;
871 gdb_bfd_requires_relocations (bfd *abfd)
873 struct gdb_bfd_data *gdata = bfd_usrdata (abfd);
875 if (gdata->relocation_computed == 0)
879 for (sect = abfd->sections; sect != NULL; sect = sect->next)
880 if ((sect->flags & SEC_RELOC) != 0)
882 gdata->needs_relocations = 1;
886 gdata->relocation_computed = 1;
889 return gdata->needs_relocations;
894 /* A callback for htab_traverse that prints a single BFD. */
897 print_one_bfd (void **slot, void *data)
900 struct gdb_bfd_data *gdata = bfd_usrdata (abfd);
901 struct ui_out *uiout = data;
902 struct cleanup *inner;
904 inner = make_cleanup_ui_out_tuple_begin_end (uiout, NULL);
905 ui_out_field_int (uiout, "refcount", gdata->refc);
906 ui_out_field_string (uiout, "addr", host_address_to_string (abfd));
907 ui_out_field_string (uiout, "filename", bfd_get_filename (abfd));
908 ui_out_text (uiout, "\n");
914 /* Implement the 'maint info bfd' command. */
917 maintenance_info_bfds (char *arg, int from_tty)
919 struct cleanup *cleanup;
920 struct ui_out *uiout = current_uiout;
922 cleanup = make_cleanup_ui_out_table_begin_end (uiout, 3, -1, "bfds");
923 ui_out_table_header (uiout, 10, ui_left, "refcount", "Refcount");
924 ui_out_table_header (uiout, 18, ui_left, "addr", "Address");
925 ui_out_table_header (uiout, 40, ui_left, "filename", "Filename");
927 ui_out_table_body (uiout);
928 htab_traverse (all_bfds, print_one_bfd, uiout);
930 do_cleanups (cleanup);
933 /* -Wmissing-prototypes */
934 extern initialize_file_ftype _initialize_gdb_bfd;
937 _initialize_gdb_bfd (void)
939 all_bfds = htab_create_alloc (10, htab_hash_pointer, htab_eq_pointer,
940 NULL, xcalloc, xfree);
942 add_cmd ("bfds", class_maintenance, maintenance_info_bfds, _("\
943 List the BFDs that are currently open."),
944 &maintenanceinfolist);