408 lines
11 KiB
C
408 lines
11 KiB
C
/* Generic BFD support for file formats.
|
|
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 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.
|
|
|
|
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. */
|
|
|
|
|
|
/*
|
|
SECTION
|
|
File formats
|
|
|
|
A format is a BFD concept of high level file contents type. The
|
|
formats supported by BFD are:
|
|
|
|
o <<bfd_object>>
|
|
|
|
The BFD may contain data, symbols, relocations and debug info.
|
|
|
|
o <<bfd_archive>>
|
|
|
|
The BFD contains other BFDs and an optional index.
|
|
|
|
o <<bfd_core>>
|
|
|
|
The BFD contains the result of an executable core dump.
|
|
|
|
SUBSECTION
|
|
File format functions
|
|
*/
|
|
|
|
#include "sysdep.h"
|
|
#include "bfd.h"
|
|
#include "libbfd.h"
|
|
|
|
/* IMPORT from targets.c. */
|
|
extern const size_t _bfd_target_vector_entries;
|
|
|
|
/*
|
|
FUNCTION
|
|
bfd_check_format
|
|
|
|
SYNOPSIS
|
|
bfd_boolean bfd_check_format (bfd *abfd, bfd_format format);
|
|
|
|
DESCRIPTION
|
|
Verify if the file attached to the BFD @var{abfd} is compatible
|
|
with the format @var{format} (i.e., one of <<bfd_object>>,
|
|
<<bfd_archive>> or <<bfd_core>>).
|
|
|
|
If the BFD has been set to a specific target before the
|
|
call, only the named target and format combination is
|
|
checked. If the target has not been set, or has been set to
|
|
<<default>>, then all the known target backends is
|
|
interrogated to determine a match. If the default target
|
|
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:
|
|
|
|
o <<bfd_error_invalid_operation>> -
|
|
if <<format>> is not one of <<bfd_object>>, <<bfd_archive>> or
|
|
<<bfd_core>>.
|
|
|
|
o <<bfd_error_system_call>> -
|
|
if an error occured during a read - even some file mismatches
|
|
can cause bfd_error_system_calls.
|
|
|
|
o <<file_not_recognised>> -
|
|
none of the backends recognised the file format.
|
|
|
|
o <<bfd_error_file_ambiguously_recognized>> -
|
|
more than one backend recognised the file format.
|
|
*/
|
|
|
|
bfd_boolean
|
|
bfd_check_format (bfd *abfd, bfd_format format)
|
|
{
|
|
return bfd_check_format_matches (abfd, format, NULL);
|
|
}
|
|
|
|
/*
|
|
FUNCTION
|
|
bfd_check_format_matches
|
|
|
|
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;
|
|
int match_count;
|
|
int ar_match_index;
|
|
|
|
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;
|
|
|
|
/* Since the target type was defaulted, check them
|
|
all in the hope that one will be uniquely recognized. */
|
|
save_targ = abfd->xvec;
|
|
match_count = 0;
|
|
ar_match_index = _bfd_target_vector_entries;
|
|
|
|
if (matching != NULL || *bfd_associated_vector != NULL)
|
|
{
|
|
bfd_size_type amt;
|
|
|
|
amt = sizeof (*matching_vector) * 2 * _bfd_target_vector_entries;
|
|
matching_vector = (const bfd_target **) bfd_malloc (amt);
|
|
if (!matching_vector)
|
|
return FALSE;
|
|
}
|
|
|
|
right_targ = 0;
|
|
ar_right_targ = 0;
|
|
|
|
/* Presume the answer is yes. */
|
|
abfd->format = format;
|
|
|
|
/* 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;
|
|
}
|
|
|
|
for (target = bfd_target_vector; *target != NULL; target++)
|
|
{
|
|
const bfd_target *temp;
|
|
bfd_error_type err;
|
|
|
|
/* Don't check the default target twice. */
|
|
if (*target == &binary_vec
|
|
|| (!abfd->target_defaulted && *target == save_targ))
|
|
continue;
|
|
|
|
abfd->xvec = *target; /* Change BFD's target temporarily. */
|
|
|
|
if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0)
|
|
goto err_ret;
|
|
|
|
/* 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 && (abfd->format != bfd_archive || bfd_has_map (abfd)))
|
|
{
|
|
/* 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])
|
|
{
|
|
match_count = 1;
|
|
break;
|
|
}
|
|
|
|
if (matching_vector)
|
|
matching_vector[match_count] = temp;
|
|
match_count++;
|
|
}
|
|
else if (temp
|
|
|| (err = bfd_get_error ()) == bfd_error_wrong_object_format
|
|
|| err == bfd_error_file_ambiguously_recognized)
|
|
{
|
|
/* An archive with no armap or objects of the wrong type,
|
|
or an ambiguous match. 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++;
|
|
}
|
|
else if (err != bfd_error_wrong_format)
|
|
goto err_ret;
|
|
}
|
|
|
|
if (match_count == 0)
|
|
{
|
|
/* Try partial matches. */
|
|
right_targ = ar_right_targ;
|
|
|
|
if (right_targ == bfd_default_vector[0])
|
|
{
|
|
match_count = 1;
|
|
}
|
|
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);
|
|
}
|
|
}
|
|
|
|
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)
|
|
break;
|
|
|
|
if (i >= 0)
|
|
{
|
|
match_count = 1;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (match_count == 1)
|
|
{
|
|
ok_ret:
|
|
abfd->xvec = right_targ; /* Change BFD's target permanently. */
|
|
|
|
/* 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);
|
|
return TRUE; /* File position has moved, BTW. */
|
|
}
|
|
|
|
if (match_count == 0)
|
|
{
|
|
err_unrecog:
|
|
bfd_set_error (bfd_error_file_not_recognized);
|
|
err_ret:
|
|
abfd->xvec = save_targ;
|
|
abfd->format = bfd_unknown;
|
|
if (matching_vector)
|
|
free (matching_vector);
|
|
return FALSE;
|
|
}
|
|
|
|
abfd->xvec = save_targ; /* Restore original target type. */
|
|
abfd->format = bfd_unknown; /* Restore original format. */
|
|
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
|
|
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.
|
|
*/
|
|
|
|
bfd_boolean
|
|
bfd_set_format (bfd *abfd, bfd_format format)
|
|
{
|
|
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;
|
|
|
|
/* Presume the answer is yes. */
|
|
abfd->format = format;
|
|
|
|
if (!BFD_SEND_FMT (abfd, _bfd_set_format, (abfd)))
|
|
{
|
|
abfd->format = bfd_unknown;
|
|
return FALSE;
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/*
|
|
FUNCTION
|
|
bfd_format_string
|
|
|
|
SYNOPSIS
|
|
const char *bfd_format_string (bfd_format format);
|
|
|
|
DESCRIPTION
|
|
Return a pointer to a const string
|
|
<<invalid>>, <<object>>, <<archive>>, <<core>>, or <<unknown>>,
|
|
depending upon the value of @var{format}.
|
|
*/
|
|
|
|
const char *
|
|
bfd_format_string (bfd_format format)
|
|
{
|
|
if (((int) format < (int) bfd_unknown)
|
|
|| ((int) format >= (int) bfd_type_end))
|
|
return "invalid";
|
|
|
|
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";
|
|
}
|
|
}
|