binutils-gdb/gdb/build-id.c

170 lines
4.4 KiB
C

/* build-id-related functions.
Copyright (C) 1991-2017 Free Software Foundation, Inc.
This file is part of GDB.
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, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "bfd.h"
#include "gdb_bfd.h"
#include "build-id.h"
#include "gdb_vecs.h"
#include "symfile.h"
#include "objfiles.h"
#include "filenames.h"
#include "gdbcore.h"
/* See build-id.h. */
const struct bfd_build_id *
build_id_bfd_get (bfd *abfd)
{
if (!bfd_check_format (abfd, bfd_object))
return NULL;
if (abfd->build_id != NULL)
return abfd->build_id;
/* No build-id */
return NULL;
}
/* See build-id.h. */
int
build_id_verify (bfd *abfd, size_t check_len, const bfd_byte *check)
{
const struct bfd_build_id *found;
int retval = 0;
found = build_id_bfd_get (abfd);
if (found == NULL)
warning (_("File \"%s\" has no build-id, file skipped"),
bfd_get_filename (abfd));
else if (found->size != check_len
|| memcmp (found->data, check, found->size) != 0)
warning (_("File \"%s\" has a different build-id, file skipped"),
bfd_get_filename (abfd));
else
retval = 1;
return retval;
}
/* See build-id.h. */
gdb_bfd_ref_ptr
build_id_to_debug_bfd (size_t build_id_len, const bfd_byte *build_id)
{
char *link, *debugdir;
VEC (char_ptr) *debugdir_vec;
struct cleanup *back_to;
int ix;
gdb_bfd_ref_ptr abfd;
int alloc_len;
/* DEBUG_FILE_DIRECTORY/.build-id/ab/cdef */
alloc_len = (strlen (debug_file_directory)
+ (sizeof "/.build-id/" - 1) + 1
+ 2 * build_id_len + (sizeof ".debug" - 1) + 1);
link = (char *) alloca (alloc_len);
/* Keep backward compatibility so that DEBUG_FILE_DIRECTORY being "" will
cause "/.build-id/..." lookups. */
debugdir_vec = dirnames_to_char_ptr_vec (debug_file_directory);
back_to = make_cleanup_free_char_ptr_vec (debugdir_vec);
for (ix = 0; VEC_iterate (char_ptr, debugdir_vec, ix, debugdir); ++ix)
{
size_t debugdir_len = strlen (debugdir);
const gdb_byte *data = build_id;
size_t size = build_id_len;
char *s;
char *filename = NULL;
struct cleanup *inner;
memcpy (link, debugdir, debugdir_len);
s = &link[debugdir_len];
s += sprintf (s, "/.build-id/");
if (size > 0)
{
size--;
s += sprintf (s, "%02x", (unsigned) *data++);
}
if (size > 0)
*s++ = '/';
while (size-- > 0)
s += sprintf (s, "%02x", (unsigned) *data++);
strcpy (s, ".debug");
if (separate_debug_file_debug)
printf_unfiltered (_(" Trying %s\n"), link);
/* lrealpath() is expensive even for the usually non-existent files. */
if (access (link, F_OK) == 0)
filename = lrealpath (link);
if (filename == NULL)
continue;
/* We expect to be silent on the non-existing files. */
inner = make_cleanup (xfree, filename);
abfd = gdb_bfd_open (filename, gnutarget, -1);
do_cleanups (inner);
if (abfd == NULL)
continue;
if (build_id_verify (abfd.get(), build_id_len, build_id))
break;
abfd.release ();
}
do_cleanups (back_to);
return abfd;
}
/* See build-id.h. */
char *
find_separate_debug_file_by_buildid (struct objfile *objfile)
{
const struct bfd_build_id *build_id;
build_id = build_id_bfd_get (objfile->obfd);
if (build_id != NULL)
{
if (separate_debug_file_debug)
printf_unfiltered (_("\nLooking for separate debug info (build-id) for "
"%s\n"), objfile_name (objfile));
gdb_bfd_ref_ptr abfd (build_id_to_debug_bfd (build_id->size,
build_id->data));
/* Prevent looping on a stripped .debug file. */
if (abfd != NULL
&& filename_cmp (bfd_get_filename (abfd.get ()),
objfile_name (objfile)) == 0)
warning (_("\"%s\": separate debug info file has no debug info"),
bfd_get_filename (abfd.get ()));
else if (abfd != NULL)
return xstrdup (bfd_get_filename (abfd.get ()));
}
return NULL;
}