| /* Generic BFD support for file formats. |
| Copyright (C) 1990, 91, 92, 93, 94, 95, 1999 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 2 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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. |
| |
| |
| */ |
| |
| #include "bfd.h" |
| #include "sysdep.h" |
| #include "libbfd.h" |
| |
| /* 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); |
| |
| 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. |
| */ |
| |
| boolean |
| bfd_check_format (abfd, format) |
| bfd *abfd; |
| bfd_format format; |
| { |
| return bfd_check_format_matches (abfd, format, NULL); |
| } |
| |
| /* |
| FUNCTION |
| bfd_check_format_matches |
| |
| SYNOPSIS |
| 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. |
| */ |
| |
| boolean |
| bfd_check_format_matches (abfd, format, matching) |
| bfd *abfd; |
| bfd_format format; |
| char ***matching; |
| { |
| extern const bfd_target binary_vec; |
| const bfd_target * const *target, *save_targ, *right_targ; |
| char **matching_vector = NULL; |
| int match_count; |
| |
| if (!bfd_read_p (abfd) || |
| ((int)(abfd->format) < (int)bfd_unknown) || |
| ((int)(abfd->format) >= (int)bfd_type_end)) { |
| bfd_set_error (bfd_error_invalid_operation); |
| return false; |
| } |
| |
| if (abfd->format != bfd_unknown) |
| return (abfd->format == format)? true: false; |
| |
| |
| /* 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; |
| if (matching) |
| { |
| matching_vector = |
| (char **) bfd_malloc (sizeof (char *) * |
| (_bfd_target_vector_entries + 1)); |
| if (!matching_vector) |
| return false; |
| matching_vector[0] = NULL; |
| *matching = matching_vector; |
| } |
| 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! */ |
| return false; |
| right_targ = BFD_SEND_FMT (abfd, _bfd_check_format, (abfd)); |
| if (right_targ) { |
| abfd->xvec = right_targ; /* Set the target as returned */ |
| if (matching) |
| free (matching_vector); |
| return true; /* File position has moved, BTW */ |
| } |
| |
| /* 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) |
| { |
| abfd->xvec = save_targ; |
| abfd->format = bfd_unknown; |
| if (matching) |
| free (matching_vector); |
| bfd_set_error (bfd_error_file_not_recognized); |
| return false; |
| } |
| } |
| |
| for (target = bfd_target_vector; *target != NULL; target++) { |
| const bfd_target *temp; |
| |
| if (*target == &binary_vec) |
| continue; |
| |
| abfd->xvec = *target; /* Change BFD's target temporarily */ |
| if (bfd_seek (abfd, (file_ptr)0, SEEK_SET) != 0) |
| return false; |
| /* 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) { /* This format checks out as ok! */ |
| right_targ = temp; |
| if (matching) |
| { |
| matching_vector[match_count] = temp->name; |
| matching_vector[match_count + 1] = NULL; |
| } |
| 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 == bfd_default_vector[0]) |
| { |
| if (matching) |
| { |
| matching_vector[0] = temp->name; |
| matching_vector[1] = NULL; |
| } |
| 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_get_error () != bfd_error_wrong_format) { |
| abfd->xvec = save_targ; |
| abfd->format = bfd_unknown; |
| if (matching && bfd_get_error () != bfd_error_file_ambiguously_recognized) |
| free (matching_vector); |
| return false; |
| } |
| } |
| |
| if (match_count == 1) { |
| abfd->xvec = right_targ; /* Change BFD's target permanently */ |
| if (matching) |
| free (matching_vector); |
| return true; /* File position has moved, BTW */ |
| } |
| |
| abfd->xvec = save_targ; /* Restore original target type */ |
| abfd->format = bfd_unknown; /* Restore original format */ |
| if (match_count == 0) |
| { |
| bfd_set_error (bfd_error_file_not_recognized); |
| if (matching) |
| free (matching_vector); |
| } |
| else |
| bfd_set_error (bfd_error_file_ambiguously_recognized); |
| return false; |
| } |
| |
| /* |
| FUNCTION |
| bfd_set_format |
| |
| SYNOPSIS |
| 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 |
| bfd_set_format (abfd, 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_set_error (bfd_error_invalid_operation); |
| return false; |
| } |
| |
| if (abfd->format != bfd_unknown) |
| return (abfd->format == format) ? true:false; |
| |
| /* 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 (format) |
| 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/assember/compiler output */ |
| case bfd_archive: |
| return "archive"; /* object archive file */ |
| case bfd_core: |
| return "core"; /* core dump */ |
| default: |
| return "unknown"; |
| } |
| } |