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Diffstat (limited to 'x/binutils/bfd/format.c')
| -rw-r--r-- | x/binutils/bfd/format.c | 436 |
1 files changed, 436 insertions, 0 deletions
diff --git a/x/binutils/bfd/format.c b/x/binutils/bfd/format.c new file mode 100644 index 0000000..9d9ee86 --- /dev/null +++ b/x/binutils/bfd/format.c @@ -0,0 +1,436 @@ +/* Generic BFD support for file formats. + Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1999, 2000, 2001, 2002, 2003 + 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 + 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 (!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) + { + bfd_size_type amt; + + *matching = NULL; + amt = sizeof (*matching_vector) * 2 * _bfd_target_vector_entries; + matching_vector = 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! */ + { + if (matching) + free (matching_vector); + 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; + bfd_error_type err; + + if (*target == &binary_vec) + continue; + + abfd->xvec = *target; /* Change BFD's target temporarily. */ + + if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0) + { + if (matching) + free (matching_vector); + 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 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) + matching_vector[match_count] = temp; + + match_count++; + +#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 ((err = bfd_get_error ()) == bfd_error_wrong_object_format + || err == bfd_error_file_ambiguously_recognized) + { + /* An archive with 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) + matching_vector[ar_match_index] = *target; + ar_match_index++; + } + else if (err != bfd_error_wrong_format) + { + abfd->xvec = save_targ; + abfd->format = bfd_unknown; + + if (matching) + free (matching_vector); + + return FALSE; + } + } + + 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 && match_count > 1) + memcpy (matching_vector, + matching_vector + _bfd_target_vector_entries, + sizeof (*matching_vector) * match_count); + } + } + + if (match_count > 1 + && bfd_associated_vector != NULL + && matching) + { + 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) + { + 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); + + 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"; + } +} |
