/* Generic BFD support for file formats.
- Copyright (C) 1990-1991 Free Software Foundation, Inc.
+ Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1999, 2000, 2001, 2002,
+ 2003, 2005, 2007, 2008, 2009 Free Software Foundation, Inc.
Written by Cygnus Support.
-This file is part of BFD, the Binary File Descriptor library.
+ This file is part of BFD, the Binary File Descriptor library.
-This program is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2 of the License, or
-(at your option) any later version.
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+ MA 02110-1301, USA. */
-You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software
-Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
/*
SECTION
- File Formats
+ File formats
A format is a BFD concept of high level file contents type. The
- formats supported by BFD are:
+ formats supported by BFD are:
o <<bfd_object>>
The BFD contains the result of an executable core dump.
-
+SUBSECTION
+ File format functions
*/
-#include "bfd.h"
#include "sysdep.h"
+#include "bfd.h"
#include "libbfd.h"
-extern bfd_target *target_vector[];
-extern bfd_target *default_vector[];
-
+/* IMPORT from targets.c. */
+extern const size_t _bfd_target_vector_entries;
/*
FUNCTION
bfd_check_format
SYNOPSIS
- boolean bfd_check_format(bfd *abfd, bfd_format format);
+ bfd_boolean bfd_check_format (bfd *abfd, bfd_format format);
DESCRIPTION
Verify if the file attached to the BFD @var{abfd} is compatible
matches, it is used. If not, exactly one target must recognize
the file, or an error results.
- The function returns <<true>> on success, otherwise <<false>>
- with one of the following error codes:
+ The function returns <<TRUE>> on success, otherwise <<FALSE>>
+ with one of the following error codes:
- o invalid_operation -
+ o <<bfd_error_invalid_operation>> -
if <<format>> is not one of <<bfd_object>>, <<bfd_archive>> or
<<bfd_core>>.
- o system_call_error -
+ o <<bfd_error_system_call>> -
if an error occured during a read - even some file mismatches
- can cause system_call_errors.
+ can cause bfd_error_system_calls.
- o file_not_recognised -
+ o <<file_not_recognised>> -
none of the backends recognised the file format.
- o file_ambiguously_recognized -
+ o <<bfd_error_file_ambiguously_recognized>> -
more than one backend recognised the file format.
-
*/
-boolean
-DEFUN(bfd_check_format,(abfd, format),
- bfd *abfd AND
- bfd_format format)
+bfd_boolean
+bfd_check_format (bfd *abfd, bfd_format format)
+{
+ return bfd_check_format_matches (abfd, format, NULL);
+}
+
+struct bfd_preserve
+{
+ void *marker;
+ void *tdata;
+ flagword flags;
+ const struct bfd_arch_info *arch_info;
+ struct bfd_section *sections;
+ struct bfd_section *section_last;
+ unsigned int section_count;
+ struct bfd_hash_table section_htab;
+};
+
+/* When testing an object for compatibility with a particular target
+ back-end, the back-end object_p function needs to set up certain
+ fields in the bfd on successfully recognizing the object. This
+ typically happens in a piecemeal fashion, with failures possible at
+ many points. On failure, the bfd is supposed to be restored to its
+ initial state, which is virtually impossible. However, restoring a
+ subset of the bfd state works in practice. This function stores
+ the subset. */
+
+static bfd_boolean
+bfd_preserve_save (bfd *abfd, struct bfd_preserve *preserve)
+{
+ preserve->tdata = abfd->tdata.any;
+ preserve->arch_info = abfd->arch_info;
+ preserve->flags = abfd->flags;
+ preserve->sections = abfd->sections;
+ preserve->section_last = abfd->section_last;
+ preserve->section_count = abfd->section_count;
+ preserve->section_htab = abfd->section_htab;
+ preserve->marker = bfd_alloc (abfd, 1);
+ if (preserve->marker == NULL)
+ return FALSE;
+
+ return bfd_hash_table_init (&abfd->section_htab, bfd_section_hash_newfunc,
+ sizeof (struct section_hash_entry));
+}
+
+/* Clear out a subset of BFD state. */
+
+static void
+bfd_reinit (bfd *abfd)
+{
+ abfd->tdata.any = NULL;
+ abfd->arch_info = &bfd_default_arch_struct;
+ abfd->flags &= BFD_FLAGS_SAVED;
+ bfd_section_list_clear (abfd);
+}
+
+/* Restores bfd state saved by bfd_preserve_save. */
+
+static void
+bfd_preserve_restore (bfd *abfd, struct bfd_preserve *preserve)
+{
+ bfd_hash_table_free (&abfd->section_htab);
+
+ abfd->tdata.any = preserve->tdata;
+ abfd->arch_info = preserve->arch_info;
+ abfd->flags = preserve->flags;
+ abfd->section_htab = preserve->section_htab;
+ abfd->sections = preserve->sections;
+ abfd->section_last = preserve->section_last;
+ abfd->section_count = preserve->section_count;
+
+ /* bfd_release frees all memory more recently bfd_alloc'd than
+ its arg, as well as its arg. */
+ bfd_release (abfd, preserve->marker);
+ preserve->marker = NULL;
+}
+
+/* Called when the bfd state saved by bfd_preserve_save is no longer
+ needed. */
+
+static void
+bfd_preserve_finish (bfd *abfd ATTRIBUTE_UNUSED, struct bfd_preserve *preserve)
{
- bfd_target **target, *save_targ, *right_targ;
- int match_count;
+ /* It would be nice to be able to free more memory here, eg. old
+ tdata, but that's not possible since these blocks are sitting
+ inside bfd_alloc'd memory. The section hash is on a separate
+ objalloc. */
+ bfd_hash_table_free (&preserve->section_htab);
+ preserve->marker = NULL;
+}
+
+/*
+FUNCTION
+ bfd_check_format_matches
- if (!bfd_read_p (abfd) ||
- ((int)(abfd->format) < (int)bfd_unknown) ||
- ((int)(abfd->format) >= (int)bfd_type_end)) {
- bfd_error = invalid_operation;
- return false;
- }
+SYNOPSIS
+ bfd_boolean bfd_check_format_matches
+ (bfd *abfd, bfd_format format, char ***matching);
+
+DESCRIPTION
+ Like <<bfd_check_format>>, except when it returns FALSE with
+ <<bfd_errno>> set to <<bfd_error_file_ambiguously_recognized>>. In that
+ case, if @var{matching} is not NULL, it will be filled in with
+ a NULL-terminated list of the names of the formats that matched,
+ allocated with <<malloc>>.
+ Then the user may choose a format and try again.
+
+ When done with the list that @var{matching} points to, the caller
+ should free it.
+*/
+
+bfd_boolean
+bfd_check_format_matches (bfd *abfd, bfd_format format, char ***matching)
+{
+ extern const bfd_target binary_vec;
+ const bfd_target * const *target;
+ const bfd_target **matching_vector = NULL;
+ const bfd_target *save_targ, *right_targ, *ar_right_targ, *match_targ;
+ int match_count, best_count, best_match;
+ int ar_match_index;
+ struct bfd_preserve preserve;
+
+ if (matching != NULL)
+ *matching = NULL;
+
+ if (!bfd_read_p (abfd)
+ || (unsigned int) abfd->format >= (unsigned int) bfd_type_end)
+ {
+ bfd_set_error (bfd_error_invalid_operation);
+ return FALSE;
+ }
if (abfd->format != bfd_unknown)
- return (abfd->format == format)? true: false;
+ return abfd->format == format;
+ if (matching != NULL || *bfd_associated_vector != NULL)
+ {
+ bfd_size_type amt;
- /* Since the target type was defaulted, check them
- all in the hope that one will be uniquely recognized. */
+ amt = sizeof (*matching_vector) * 2 * _bfd_target_vector_entries;
+ matching_vector = (const bfd_target **) bfd_malloc (amt);
+ if (!matching_vector)
+ return FALSE;
+ }
+ /* Presume the answer is yes. */
+ abfd->format = format;
save_targ = abfd->xvec;
+ preserve.marker = NULL;
+
+ /* If the target type was explicitly specified, just check that target. */
+ if (!abfd->target_defaulted)
+ {
+ if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0) /* rewind! */
+ goto err_ret;
+
+ right_targ = BFD_SEND_FMT (abfd, _bfd_check_format, (abfd));
+
+ if (right_targ)
+ goto ok_ret;
+
+ /* For a long time the code has dropped through to check all
+ targets if the specified target was wrong. I don't know why,
+ and I'm reluctant to change it. However, in the case of an
+ archive, it can cause problems. If the specified target does
+ not permit archives (e.g., the binary target), then we should
+ not allow some other target to recognize it as an archive, but
+ should instead allow the specified target to recognize it as an
+ object. When I first made this change, it broke the PE target,
+ because the specified pei-i386 target did not recognize the
+ actual pe-i386 archive. Since there may be other problems of
+ this sort, I changed this test to check only for the binary
+ target. */
+ if (format == bfd_archive && save_targ == &binary_vec)
+ goto err_unrecog;
+ }
+
+ /* Since the target type was defaulted, check them all in the hope
+ that one will be uniquely recognized. */
+ right_targ = NULL;
+ ar_right_targ = NULL;
+ match_targ = NULL;
+ best_match = 256;
+ best_count = 0;
match_count = 0;
- right_targ = 0;
+ ar_match_index = _bfd_target_vector_entries;
+ for (target = bfd_target_vector; *target != NULL; target++)
+ {
+ const bfd_target *temp;
- /* presume the answer is yes */
- abfd->format = format;
+ /* Don't check the default target twice. */
+ if (*target == &binary_vec
+ || (!abfd->target_defaulted && *target == save_targ)
+ || (*target)->match_priority > best_match)
+ continue;
- /* If the target type was explicitly specified, just check that target. */
+ /* If we already tried a match, the bfd is modified and may
+ have sections attached, which will confuse the next
+ _bfd_check_format call. */
+ bfd_reinit (abfd);
+
+ /* Change BFD's target temporarily. */
+ abfd->xvec = *target;
- if (!abfd->target_defaulted) {
- bfd_seek (abfd, (file_ptr)0, SEEK_SET); /* rewind! */
+ if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0)
+ goto err_ret;
- right_targ = BFD_SEND_FMT (abfd, _bfd_check_format, (abfd));
- if (right_targ) {
- abfd->xvec = right_targ; /* Set the target as returned */
- return true; /* File position has moved, BTW */
+ /* If _bfd_check_format neglects to set bfd_error, assume
+ bfd_error_wrong_format. We didn't used to even pay any
+ attention to bfd_error, so I suspect that some
+ _bfd_check_format might have this problem. */
+ bfd_set_error (bfd_error_wrong_format);
+
+ temp = BFD_SEND_FMT (abfd, _bfd_check_format, (abfd));
+ if (temp)
+ {
+ match_targ = temp;
+ if (preserve.marker != NULL)
+ bfd_preserve_finish (abfd, &preserve);
+
+ if (abfd->format != bfd_archive
+ || (bfd_has_map (abfd)
+ && bfd_get_error () != bfd_error_wrong_object_format))
+ {
+ /* This format checks out as ok! */
+ right_targ = temp;
+
+ /* If this is the default target, accept it, even if
+ other targets might match. People who want those
+ other targets have to set the GNUTARGET variable. */
+ if (temp == bfd_default_vector[0])
+ goto ok_ret;
+
+ if (matching_vector)
+ matching_vector[match_count] = temp;
+ match_count++;
+
+ if (temp->match_priority < best_match)
+ {
+ best_match = temp->match_priority;
+ best_count = 0;
+ }
+ best_count++;
+ }
+ else
+ {
+ /* An archive with no armap or objects of the wrong
+ type. We want this target to match if we get no
+ better matches. */
+ if (ar_right_targ != bfd_default_vector[0])
+ ar_right_targ = *target;
+ if (matching_vector)
+ matching_vector[ar_match_index] = *target;
+ ar_match_index++;
+ }
+
+ if (!bfd_preserve_save (abfd, &preserve))
+ goto err_ret;
+ }
+ else if (bfd_get_error () != bfd_error_wrong_format)
+ goto err_ret;
}
- }
-
- for (target = target_vector; *target != NULL; target++) {
- bfd_target *temp;
-
- abfd->xvec = *target; /* Change BFD's target temporarily */
- bfd_seek (abfd, (file_ptr)0, SEEK_SET);
- /* If _bfd_check_format neglects to set bfd_error, assume wrong_format.
- We didn't used to even pay any attention to bfd_error, so I suspect
- that some _bfd_check_format might have this problem. */
- bfd_error = wrong_format;
- temp = BFD_SEND_FMT (abfd, _bfd_check_format, (abfd));
- if (temp) { /* This format checks out as ok! */
- right_targ = temp;
- match_count++;
- /* If this is the default target, accept it, even if other targets
- might match. People who want those other targets have to set
- the GNUTARGET variable. */
- if (temp == default_vector[0])
+
+ if (best_count == 1)
+ match_count = 1;
+
+ if (match_count == 0)
+ {
+ /* Try partial matches. */
+ right_targ = ar_right_targ;
+
+ if (right_targ == bfd_default_vector[0])
{
match_count = 1;
- break;
}
-#ifdef GNU960
- /* Big- and little-endian b.out archives look the same, but it doesn't
- * matter: there is no difference in their headers, and member file byte
- * orders will (I hope) be handled appropriately by bfd. Ditto for big
- * and little coff archives. And the 4 coff/b.out object formats are
- * unambiguous. So accept the first match we find.
- */
- break;
-#endif
- } else if (bfd_error != wrong_format) {
+ else
+ {
+ match_count = ar_match_index - _bfd_target_vector_entries;
+
+ if (matching_vector && match_count > 1)
+ memcpy (matching_vector,
+ matching_vector + _bfd_target_vector_entries,
+ sizeof (*matching_vector) * match_count);
+ }
+ }
+
+ /* We have more than one equally good match. If any of the best
+ matches is a target in config.bfd targ_defvec or targ_selvecs,
+ choose it. */
+ if (match_count > 1)
+ {
+ const bfd_target * const *assoc = bfd_associated_vector;
+
+ while ((right_targ = *assoc++) != NULL)
+ {
+ int i = match_count;
+
+ while (--i >= 0)
+ if (matching_vector[i] == right_targ
+ && right_targ->match_priority <= best_match)
+ break;
+
+ if (i >= 0)
+ {
+ match_count = 1;
+ break;
+ }
+ }
+ }
+
+ /* We still have more than one equally good match, and at least some
+ of the targets support match priority. Choose the first of the
+ best matches. */
+ if (match_count > 1 && best_count != match_count)
+ {
+ int i;
+
+ for (i = 0; i < match_count; i++)
+ {
+ right_targ = matching_vector[i];
+ if (right_targ->match_priority <= best_match)
+ break;
+ }
+ match_count = 1;
+ }
+
+ /* There is way too much undoing of half-known state here. We
+ really shouldn't iterate on live bfd's. Note that saving the
+ whole bfd and restoring it would be even worse; the first thing
+ you notice is that the cached bfd file position gets out of sync. */
+ if (preserve.marker != NULL)
+ bfd_preserve_restore (abfd, &preserve);
+
+ if (match_count == 1)
+ {
+ abfd->xvec = right_targ;
+ /* If we come out of the loop knowing that the last target that
+ matched is the one we want, then ABFD should still be in a usable
+ state (except possibly for XVEC). */
+ if (match_targ != right_targ)
+ {
+ bfd_reinit (abfd);
+ if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0)
+ goto err_ret;
+ match_targ = BFD_SEND_FMT (abfd, _bfd_check_format, (abfd));
+ BFD_ASSERT (match_targ != NULL);
+ }
+
+ ok_ret:
+ /* If the file was opened for update, then `output_has_begun'
+ some time ago when the file was created. Do not recompute
+ sections sizes or alignments in _bfd_set_section_contents.
+ We can not set this flag until after checking the format,
+ because it will interfere with creation of BFD sections. */
+ if (abfd->direction == both_direction)
+ abfd->output_has_begun = TRUE;
+
+ if (matching_vector)
+ free (matching_vector);
+
+ /* File position has moved, BTW. */
+ return TRUE;
+ }
+
+ if (match_count == 0)
+ {
+ err_unrecog:
+ bfd_set_error (bfd_error_file_not_recognized);
+ err_ret:
abfd->xvec = save_targ;
abfd->format = bfd_unknown;
- return false;
+ if (matching_vector)
+ free (matching_vector);
+ if (preserve.marker != NULL)
+ bfd_preserve_restore (abfd, &preserve);
+ return FALSE;
}
- }
-
- if (match_count == 1) {
- abfd->xvec = right_targ; /* Change BFD's target permanently */
- return true; /* File position has moved, BTW */
- }
-
- abfd->xvec = save_targ; /* Restore original target type */
- abfd->format = bfd_unknown; /* Restore original format */
- bfd_error = ((match_count == 0) ? file_not_recognized :
- file_ambiguously_recognized);
- return false;
-}
+ /* Restore original target type and format. */
+ abfd->xvec = save_targ;
+ abfd->format = bfd_unknown;
+ bfd_set_error (bfd_error_file_ambiguously_recognized);
+
+ if (matching)
+ {
+ *matching = (char **) matching_vector;
+ matching_vector[match_count] = NULL;
+ /* Return target names. This is a little nasty. Maybe we
+ should do another bfd_malloc? */
+ while (--match_count >= 0)
+ {
+ const char *name = matching_vector[match_count]->name;
+ *(const char **) &matching_vector[match_count] = name;
+ }
+ }
+ return FALSE;
+}
/*
FUNCTION
bfd_set_format
SYNOPSIS
- boolean bfd_set_format(bfd *abfd, bfd_format format);
+ bfd_boolean bfd_set_format (bfd *abfd, bfd_format format);
DESCRIPTION
This function sets the file format of the BFD @var{abfd} to the
format @var{format}. If the target set in the BFD does not
support the format requested, the format is invalid, or the BFD
is not open for writing, then an error occurs.
-
*/
-boolean
-DEFUN(bfd_set_format,(abfd, format),
- bfd *abfd AND
- bfd_format format)
+bfd_boolean
+bfd_set_format (bfd *abfd, bfd_format format)
{
-
- if (bfd_read_p (abfd) ||
- ((int)abfd->format < (int)bfd_unknown) ||
- ((int)abfd->format >= (int)bfd_type_end)) {
- bfd_error = invalid_operation;
- return false;
- }
+ if (bfd_read_p (abfd)
+ || (unsigned int) abfd->format >= (unsigned int) bfd_type_end)
+ {
+ bfd_set_error (bfd_error_invalid_operation);
+ return FALSE;
+ }
if (abfd->format != bfd_unknown)
- return (abfd->format == format) ? true:false;
+ return abfd->format == format;
- /* presume the answer is yes */
+ /* Presume the answer is yes. */
abfd->format = format;
- if (!BFD_SEND_FMT (abfd, _bfd_set_format, (abfd))) {
- abfd->format = bfd_unknown;
- return false;
- }
+ if (!BFD_SEND_FMT (abfd, _bfd_set_format, (abfd)))
+ {
+ abfd->format = bfd_unknown;
+ return FALSE;
+ }
- return true;
+ return TRUE;
}
-
/*
FUNCTION
bfd_format_string
SYNOPSIS
- CONST char *bfd_format_string(bfd_format format);
+ const char *bfd_format_string (bfd_format format);
DESCRIPTION
Return a pointer to a const string
depending upon the value of @var{format}.
*/
-CONST char *
-DEFUN(bfd_format_string,(format),
- bfd_format format)
+const char *
+bfd_format_string (bfd_format format)
{
- if (((int)format <(int) bfd_unknown)
- || ((int)format >=(int) bfd_type_end))
+ if (((int) format < (int) bfd_unknown)
+ || ((int) format >= (int) bfd_type_end))
return "invalid";
-
- switch (format) {
- case bfd_object:
- return "object"; /* linker/assember/compiler output */
- case bfd_archive:
- return "archive"; /* object archive file */
- case bfd_core:
- return "core"; /* core dump */
- default:
- return "unknown";
- }
+
+ switch (format)
+ {
+ case bfd_object:
+ return "object"; /* Linker/assembler/compiler output. */
+ case bfd_archive:
+ return "archive"; /* Object archive file. */
+ case bfd_core:
+ return "core"; /* Core dump. */
+ default:
+ return "unknown";
+ }
}