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https://sourceware.org/git/binutils-gdb.git
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20bf7711bc
Running the gdb test suite with the thread sanitizer enabled shows a race when bfd_check_format_matches and bfd_cache_close_all are called simultaneously on different threads. This patch fixes this race by having bfd_check_format_matches temporarily remove the BFD from the file descriptor cache -- leaving it open while format-checking proceeds. In this setup, the BFD client is responsible for closing the BFD again on the "checking" thread, should that be desired. gdb does this by calling bfd_cache_close in the relevant worker thread. An earlier version of this patch omitted the "possibly_cached" helper function. However, this ran into crashes in the binutils test suite involving the archive-checking abort in bfd_cache_lookup_worker. I do not understand the purpose of this check, so I've simply had the new function work around it. I couldn't find any comments explaining this situation, either. I suspect that there may still be races related to this case, but I don't think I have access to the platforms where gdb deals with archives. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31264
799 lines
23 KiB
C
799 lines
23 KiB
C
/* Generic BFD support for file formats.
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Copyright (C) 1990-2024 Free Software Foundation, Inc.
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Written by Cygnus Support.
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This file is part of BFD, the Binary File Descriptor library.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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MA 02110-1301, USA. */
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/*
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SECTION
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File formats
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A format is a BFD concept of high level file contents type. The
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formats supported by BFD are:
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o <<bfd_object>>
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The BFD may contain data, symbols, relocations and debug info.
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o <<bfd_archive>>
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The BFD contains other BFDs and an optional index.
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o <<bfd_core>>
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The BFD contains the result of an executable core dump.
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SUBSECTION
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File format functions
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*/
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#include "sysdep.h"
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#include "bfd.h"
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#include "libbfd.h"
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/* IMPORT from targets.c. */
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extern const size_t _bfd_target_vector_entries;
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/*
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FUNCTION
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bfd_check_format
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SYNOPSIS
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bool bfd_check_format (bfd *abfd, bfd_format format);
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DESCRIPTION
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Verify if the file attached to the BFD @var{abfd} is compatible
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with the format @var{format} (i.e., one of <<bfd_object>>,
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<<bfd_archive>> or <<bfd_core>>).
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If the BFD has been set to a specific target before the
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call, only the named target and format combination is
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checked. If the target has not been set, or has been set to
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<<default>>, then all the known target backends is
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interrogated to determine a match. If the default target
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matches, it is used. If not, exactly one target must recognize
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the file, or an error results.
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The function returns <<TRUE>> on success, otherwise <<FALSE>>
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with one of the following error codes:
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o <<bfd_error_invalid_operation>> -
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if <<format>> is not one of <<bfd_object>>, <<bfd_archive>> or
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<<bfd_core>>.
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o <<bfd_error_system_call>> -
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if an error occured during a read - even some file mismatches
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can cause bfd_error_system_calls.
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o <<file_not_recognised>> -
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none of the backends recognised the file format.
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o <<bfd_error_file_ambiguously_recognized>> -
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more than one backend recognised the file format.
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When calling bfd_check_format (or bfd_check_format_matches),
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any underlying file descriptor will be kept open for the
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duration of the call. This is done to avoid races when
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another thread calls bfd_cache_close_all. In this scenario,
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the thread calling bfd_check_format must call bfd_cache_close
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itself.
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*/
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bool
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bfd_check_format (bfd *abfd, bfd_format format)
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{
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return bfd_check_format_matches (abfd, format, NULL);
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}
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struct bfd_preserve
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{
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void *marker;
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void *tdata;
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flagword flags;
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const struct bfd_iovec *iovec;
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void *iostream;
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const struct bfd_arch_info *arch_info;
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const struct bfd_build_id *build_id;
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bfd_cleanup cleanup;
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struct bfd_section *sections;
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struct bfd_section *section_last;
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unsigned int section_count;
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unsigned int section_id;
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unsigned int symcount;
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bool read_only;
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bfd_vma start_address;
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struct bfd_hash_table section_htab;
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};
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/* When testing an object for compatibility with a particular target
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back-end, the back-end object_p function needs to set up certain
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fields in the bfd on successfully recognizing the object. This
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typically happens in a piecemeal fashion, with failures possible at
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many points. On failure, the bfd is supposed to be restored to its
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initial state, which is virtually impossible. However, restoring a
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subset of the bfd state works in practice. This function stores
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the subset. */
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static bool
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bfd_preserve_save (bfd *abfd, struct bfd_preserve *preserve,
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bfd_cleanup cleanup)
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{
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preserve->tdata = abfd->tdata.any;
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preserve->arch_info = abfd->arch_info;
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preserve->flags = abfd->flags;
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preserve->iovec = abfd->iovec;
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preserve->iostream = abfd->iostream;
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preserve->sections = abfd->sections;
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preserve->section_last = abfd->section_last;
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preserve->section_count = abfd->section_count;
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preserve->section_id = _bfd_section_id;
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preserve->symcount = abfd->symcount;
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preserve->read_only = abfd->read_only;
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preserve->start_address = abfd->start_address;
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preserve->section_htab = abfd->section_htab;
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preserve->marker = bfd_alloc (abfd, 1);
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preserve->build_id = abfd->build_id;
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preserve->cleanup = cleanup;
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if (preserve->marker == NULL)
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return false;
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return bfd_hash_table_init (&abfd->section_htab, bfd_section_hash_newfunc,
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sizeof (struct section_hash_entry));
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}
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/* A back-end object_p function may flip a bfd from file backed to
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in-memory, eg. pe_ILF_object_p. In that case to restore the
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original IO state we need to reopen the file. Conversely, if we
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are restoring a previously matched pe ILF format and have been
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checking further target matches using file IO then we need to close
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the file and detach the bfd from the cache lru list. */
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static void
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io_reinit (bfd *abfd, struct bfd_preserve *preserve)
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{
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if (abfd->iovec != preserve->iovec)
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{
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/* Handle file backed to in-memory transition. bfd_cache_close
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won't do anything unless abfd->iovec is the cache_iovec.
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Don't be tempted to call iovec->bclose here. We don't want
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to call memory_bclose, which would free the bim. The bim
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must be kept if bfd_check_format_matches is going to decide
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later that the PE format needing it is in fact the correct
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target match. */
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bfd_cache_close (abfd);
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abfd->iovec = preserve->iovec;
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abfd->iostream = preserve->iostream;
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/* Handle in-memory to file backed transition. */
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if ((abfd->flags & BFD_CLOSED_BY_CACHE) != 0
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&& (abfd->flags & BFD_IN_MEMORY) != 0
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&& (preserve->flags & BFD_CLOSED_BY_CACHE) == 0
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&& (preserve->flags & BFD_IN_MEMORY) == 0)
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bfd_open_file (abfd);
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}
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abfd->flags = preserve->flags;
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}
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/* Clear out a subset of BFD state. */
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static void
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bfd_reinit (bfd *abfd, unsigned int section_id,
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struct bfd_preserve *preserve, bfd_cleanup cleanup)
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{
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_bfd_section_id = section_id;
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if (cleanup)
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cleanup (abfd);
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abfd->tdata.any = NULL;
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abfd->arch_info = &bfd_default_arch_struct;
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io_reinit (abfd, preserve);
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abfd->symcount = 0;
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abfd->read_only = 0;
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abfd->start_address = 0;
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abfd->build_id = NULL;
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bfd_section_list_clear (abfd);
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}
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/* Restores bfd state saved by bfd_preserve_save. */
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static bfd_cleanup
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bfd_preserve_restore (bfd *abfd, struct bfd_preserve *preserve)
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{
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bfd_hash_table_free (&abfd->section_htab);
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abfd->tdata.any = preserve->tdata;
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abfd->arch_info = preserve->arch_info;
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io_reinit (abfd, preserve);
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abfd->section_htab = preserve->section_htab;
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abfd->sections = preserve->sections;
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abfd->section_last = preserve->section_last;
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abfd->section_count = preserve->section_count;
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_bfd_section_id = preserve->section_id;
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abfd->symcount = preserve->symcount;
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abfd->read_only = preserve->read_only;
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abfd->start_address = preserve->start_address;
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abfd->build_id = preserve->build_id;
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/* bfd_release frees all memory more recently bfd_alloc'd than
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its arg, as well as its arg. */
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bfd_release (abfd, preserve->marker);
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preserve->marker = NULL;
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return preserve->cleanup;
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}
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/* Called when the bfd state saved by bfd_preserve_save is no longer
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needed. */
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static void
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bfd_preserve_finish (bfd *abfd ATTRIBUTE_UNUSED, struct bfd_preserve *preserve)
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{
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if (preserve->cleanup)
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{
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/* Run the cleanup, assuming that all it will need is the
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tdata at the time the cleanup was returned. */
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void *tdata = abfd->tdata.any;
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abfd->tdata.any = preserve->tdata;
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preserve->cleanup (abfd);
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abfd->tdata.any = tdata;
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}
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/* It would be nice to be able to free more memory here, eg. old
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tdata, but that's not possible since these blocks are sitting
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inside bfd_alloc'd memory. The section hash is on a separate
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objalloc. */
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bfd_hash_table_free (&preserve->section_htab);
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preserve->marker = NULL;
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}
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static void
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print_warnmsg (struct per_xvec_message **list)
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{
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for (struct per_xvec_message *warn = *list; warn; warn = warn->next)
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_bfd_error_handler ("%s", warn->message);
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}
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static void
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clear_warnmsg (struct per_xvec_message **list)
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{
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struct per_xvec_message *warn = *list;
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while (warn)
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{
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struct per_xvec_message *next = warn->next;
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free (warn);
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warn = next;
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}
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*list = NULL;
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}
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/* Free all the storage in LIST. Note that the first element of LIST
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is special and is assumed to be stack-allocated. TARG is used for
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re-issuing warning messages. If TARG is PER_XVEC_NO_TARGET, then
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it acts like a sort of wildcard -- messages are only reissued if
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they are all associated with a single BFD target, regardless of
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which one it is. If TARG is anything else, then only messages
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associated with TARG are emitted. */
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static void
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print_and_clear_messages (struct per_xvec_messages *list,
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const bfd_target *targ)
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{
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struct per_xvec_messages *iter = list;
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if (targ == PER_XVEC_NO_TARGET && list->next == NULL)
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print_warnmsg (&list->messages);
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while (iter != NULL)
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{
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struct per_xvec_messages *next = iter->next;
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if (iter->targ == targ)
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print_warnmsg (&iter->messages);
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clear_warnmsg (&iter->messages);
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if (iter != list)
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free (iter);
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iter = next;
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}
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}
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/* This a copy of lto_section defined in GCC (lto-streamer.h). */
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struct lto_section
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{
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int16_t major_version;
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int16_t minor_version;
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unsigned char slim_object;
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/* Flags is a private field that is not defined publicly. */
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uint16_t flags;
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};
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/* Set lto_type in ABFD. */
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static void
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bfd_set_lto_type (bfd *abfd ATTRIBUTE_UNUSED)
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{
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#if BFD_SUPPORTS_PLUGINS
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if (abfd->format == bfd_object
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&& abfd->lto_type == lto_non_object
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&& (abfd->flags & (DYNAMIC | EXEC_P)) == 0)
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{
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asection *sec;
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enum bfd_lto_object_type type = lto_non_ir_object;
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struct lto_section lsection;
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/* GCC uses .gnu.lto_.lto.<some_hash> as a LTO bytecode information
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section. */
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for (sec = abfd->sections; sec != NULL; sec = sec->next)
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if (startswith (sec->name, ".gnu.lto_.lto.")
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&& bfd_get_section_contents (abfd, sec, &lsection, 0,
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sizeof (struct lto_section)))
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{
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if (lsection.slim_object)
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type = lto_slim_ir_object;
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else
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type = lto_fat_ir_object;
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break;
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}
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abfd->lto_type = type;
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}
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#endif
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}
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/*
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FUNCTION
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bfd_check_format_matches
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SYNOPSIS
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bool bfd_check_format_matches
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(bfd *abfd, bfd_format format, char ***matching);
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DESCRIPTION
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Like <<bfd_check_format>>, except when it returns FALSE with
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<<bfd_errno>> set to <<bfd_error_file_ambiguously_recognized>>. In that
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case, if @var{matching} is not NULL, it will be filled in with
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a NULL-terminated list of the names of the formats that matched,
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allocated with <<malloc>>.
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Then the user may choose a format and try again.
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When done with the list that @var{matching} points to, the caller
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should free it.
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*/
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bool
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bfd_check_format_matches (bfd *abfd, bfd_format format, char ***matching)
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{
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extern const bfd_target binary_vec;
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#if BFD_SUPPORTS_PLUGINS
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extern const bfd_target plugin_vec;
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#endif
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const bfd_target * const *target;
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const bfd_target **matching_vector = NULL;
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const bfd_target *save_targ, *right_targ, *ar_right_targ, *match_targ;
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int match_count, best_count, best_match;
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int ar_match_index;
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unsigned int initial_section_id = _bfd_section_id;
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struct bfd_preserve preserve, preserve_match;
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bfd_cleanup cleanup = NULL;
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struct per_xvec_messages messages = { abfd, PER_XVEC_NO_TARGET, NULL, NULL };
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struct per_xvec_messages *orig_messages;
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bool old_in_format_matches;
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if (matching != NULL)
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*matching = NULL;
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if (!bfd_read_p (abfd)
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|| (unsigned int) abfd->format >= (unsigned int) bfd_type_end)
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{
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bfd_set_error (bfd_error_invalid_operation);
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return false;
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}
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if (abfd->format != bfd_unknown)
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{
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bfd_set_lto_type (abfd);
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return abfd->format == format;
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}
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if (matching != NULL || *bfd_associated_vector != NULL)
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{
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size_t amt;
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amt = sizeof (*matching_vector) * 2 * _bfd_target_vector_entries;
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matching_vector = (const bfd_target **) bfd_malloc (amt);
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if (!matching_vector)
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return false;
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}
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/* Avoid clashes with bfd_cache_close_all running in another
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thread. */
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if (!bfd_cache_set_uncloseable (abfd, true, &old_in_format_matches))
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return false;
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/* Presume the answer is yes. */
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abfd->format = format;
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save_targ = abfd->xvec;
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/* Don't report errors on recursive calls checking the first element
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of an archive. */
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orig_messages = _bfd_set_error_handler_caching (&messages);
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preserve_match.marker = NULL;
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if (!bfd_preserve_save (abfd, &preserve, NULL))
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goto err_ret;
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|
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/* If the target type was explicitly specified, just check that target. */
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if (!abfd->target_defaulted)
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{
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if (bfd_seek (abfd, 0, SEEK_SET) != 0) /* rewind! */
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goto err_ret;
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cleanup = BFD_SEND_FMT (abfd, _bfd_check_format, (abfd));
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|
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if (cleanup)
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goto ok_ret;
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/* For a long time the code has dropped through to check all
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targets if the specified target was wrong. I don't know why,
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and I'm reluctant to change it. However, in the case of an
|
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archive, it can cause problems. If the specified target does
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|
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
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target. */
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if (format == bfd_archive && save_targ == &binary_vec)
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goto err_unrecog;
|
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}
|
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|
|
/* Since the target type was defaulted, check them all in the hope
|
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that one will be uniquely recognized. */
|
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right_targ = NULL;
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ar_right_targ = NULL;
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match_targ = NULL;
|
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best_match = 256;
|
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best_count = 0;
|
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match_count = 0;
|
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ar_match_index = _bfd_target_vector_entries;
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|
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for (target = bfd_target_vector; *target != NULL; target++)
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{
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void **high_water;
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|
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/* The binary target matches anything, so don't return it when
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|
searching. Don't match the plugin target if we have another
|
|
alternative since we want to properly set the input format
|
|
before allowing a plugin to claim the file. Also, don't
|
|
check the default target twice. */
|
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if (*target == &binary_vec
|
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#if BFD_SUPPORTS_PLUGINS
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|| (match_count != 0 && *target == &plugin_vec)
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#endif
|
|
|| (!abfd->target_defaulted && *target == save_targ))
|
|
continue;
|
|
|
|
/* 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, initial_section_id, &preserve, cleanup);
|
|
/* Free bfd_alloc memory too. If we have matched and preserved
|
|
a target then the high water mark is that much higher. */
|
|
if (preserve_match.marker)
|
|
high_water = &preserve_match.marker;
|
|
else
|
|
high_water = &preserve.marker;
|
|
bfd_release (abfd, *high_water);
|
|
*high_water = bfd_alloc (abfd, 1);
|
|
|
|
/* Change BFD's target temporarily. */
|
|
abfd->xvec = *target;
|
|
|
|
if (bfd_seek (abfd, 0, SEEK_SET) != 0)
|
|
goto err_ret;
|
|
|
|
cleanup = BFD_SEND_FMT (abfd, _bfd_check_format, (abfd));
|
|
if (cleanup)
|
|
{
|
|
int match_priority = abfd->xvec->match_priority;
|
|
#if BFD_SUPPORTS_PLUGINS
|
|
/* If this object can be handled by a plugin, give that the
|
|
lowest priority; objects both handled by a plugin and
|
|
with an underlying object format will be claimed
|
|
separately by the plugin. */
|
|
if (*target == &plugin_vec)
|
|
match_priority = (*target)->match_priority;
|
|
#endif
|
|
|
|
if (abfd->format != bfd_archive
|
|
|| (bfd_has_map (abfd)
|
|
&& bfd_get_error () != bfd_error_wrong_object_format))
|
|
{
|
|
/* 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 (abfd->xvec == bfd_default_vector[0])
|
|
goto ok_ret;
|
|
|
|
if (matching_vector)
|
|
matching_vector[match_count] = abfd->xvec;
|
|
match_count++;
|
|
|
|
if (match_priority < best_match)
|
|
{
|
|
best_match = match_priority;
|
|
best_count = 0;
|
|
}
|
|
if (match_priority <= best_match)
|
|
{
|
|
/* This format checks out as ok! */
|
|
right_targ = abfd->xvec;
|
|
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 (preserve_match.marker == NULL)
|
|
{
|
|
match_targ = abfd->xvec;
|
|
if (!bfd_preserve_save (abfd, &preserve_match, cleanup))
|
|
goto err_ret;
|
|
cleanup = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
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;
|
|
}
|
|
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 (matching_vector && 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_match.marker != NULL)
|
|
cleanup = bfd_preserve_restore (abfd, &preserve_match);
|
|
|
|
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). This is not just an
|
|
optimisation. In the case of plugins a match against the
|
|
plugin target can result in the bfd being changed such that
|
|
it no longer matches the plugin target, nor will it match
|
|
RIGHT_TARG again. */
|
|
if (match_targ != right_targ)
|
|
{
|
|
bfd_reinit (abfd, initial_section_id, &preserve, cleanup);
|
|
bfd_release (abfd, preserve.marker);
|
|
if (bfd_seek (abfd, 0, SEEK_SET) != 0)
|
|
goto err_ret;
|
|
cleanup = BFD_SEND_FMT (abfd, _bfd_check_format, (abfd));
|
|
BFD_ASSERT (cleanup != 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;
|
|
|
|
free (matching_vector);
|
|
if (preserve_match.marker != NULL)
|
|
bfd_preserve_finish (abfd, &preserve_match);
|
|
bfd_preserve_finish (abfd, &preserve);
|
|
_bfd_restore_error_handler_caching (orig_messages);
|
|
|
|
print_and_clear_messages (&messages, abfd->xvec);
|
|
|
|
bfd_set_lto_type (abfd);
|
|
|
|
/* File position has moved, BTW. */
|
|
return bfd_cache_set_uncloseable (abfd, old_in_format_matches, NULL);
|
|
}
|
|
|
|
if (match_count == 0)
|
|
{
|
|
err_unrecog:
|
|
bfd_set_error (bfd_error_file_not_recognized);
|
|
err_ret:
|
|
if (cleanup)
|
|
cleanup (abfd);
|
|
abfd->xvec = save_targ;
|
|
abfd->format = bfd_unknown;
|
|
free (matching_vector);
|
|
goto out;
|
|
}
|
|
|
|
/* 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;
|
|
}
|
|
}
|
|
else
|
|
free (matching_vector);
|
|
if (cleanup)
|
|
cleanup (abfd);
|
|
out:
|
|
if (preserve_match.marker != NULL)
|
|
bfd_preserve_finish (abfd, &preserve_match);
|
|
bfd_preserve_restore (abfd, &preserve);
|
|
_bfd_restore_error_handler_caching (orig_messages);
|
|
print_and_clear_messages (&messages, PER_XVEC_NO_TARGET);
|
|
bfd_cache_set_uncloseable (abfd, old_in_format_matches, NULL);
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
FUNCTION
|
|
bfd_set_format
|
|
|
|
SYNOPSIS
|
|
bool 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.
|
|
*/
|
|
|
|
bool
|
|
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";
|
|
}
|
|
}
|