mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-26 23:10:06 +00:00
82eef55f8f
This commit adds a new _dl_open_hook entry for dlvsym and implements the function using the existing dl_lookup_symbol_x function supplied by the dynamic loader. A new hook variable, _dl_open_hook2, is introduced, which should make this change suitable for backporting: For old statically linked binaries, __libc_dlvsym will always return NULL.
126 lines
4.3 KiB
C
126 lines
4.3 KiB
C
/* Compare dlvsym and __libc_dlvsym results. Common code.
|
|
Copyright (C) 2017 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
/* compare_vsyms is the main entry point for these tests.
|
|
|
|
Indirectly, It calls __libc_dlvsym (from libc.so; internal
|
|
interface) and dlvsym (from libdl.so; public interface) to compare
|
|
the results for a selected set of symbols in libc.so which
|
|
typically have more than one symbol version. The two functions are
|
|
implemented by somewhat different code, and this test checks that
|
|
their results are the same.
|
|
|
|
The versions are generated to range from GLIBC_2.0 to GLIBC_2.Y,
|
|
with Y being the current __GLIBC_MINOR__ version plus two. In
|
|
addition, there is a list of special symbol versions of the form
|
|
GLIBC_2.Y.Z, which were used for some releases.
|
|
|
|
Comparing the two dlvsym results at versions which do not actually
|
|
exist does not test much, but it will not contribute to false test
|
|
failures, either. */
|
|
|
|
#include <array_length.h>
|
|
#include <gnu/lib-names.h>
|
|
#include <stdbool.h>
|
|
#include <stdio.h>
|
|
#include <support/check.h>
|
|
#include <support/xdlfcn.h>
|
|
|
|
/* Run consistency check for versioned symbol NAME@VERSION. NB: We
|
|
may execute in a shared object, so exit on error for proper error
|
|
reporting. */
|
|
static void
|
|
compare_vsyms_0 (void *libc_handle, const char *name, const char *version,
|
|
bool *pfound)
|
|
{
|
|
void *dlvsym_address = dlvsym (libc_handle, name, version);
|
|
void *libc_dlvsym_address
|
|
= __libc_dlvsym (libc_handle, name, version);
|
|
if (dlvsym_address != libc_dlvsym_address)
|
|
FAIL_EXIT1 ("%s@%s mismatch: %p != %p",
|
|
name, version, dlvsym_address, libc_dlvsym_address);
|
|
if (dlvsym_address != NULL)
|
|
*pfound = true;
|
|
}
|
|
|
|
|
|
/* Run consistency check for versioned symbol NAME at multiple symbol
|
|
version. */
|
|
static void
|
|
compare_vsyms_1 (void *libc_handle, const char *name)
|
|
{
|
|
bool found = false;
|
|
|
|
/* Historic versions which do not follow the usual GLIBC_2.Y
|
|
pattern, to increase test coverage. Not all architectures have
|
|
those, but probing additional versions does not hurt. */
|
|
static const char special_versions[][12] =
|
|
{
|
|
"GLIBC_2.1.1",
|
|
"GLIBC_2.1.2",
|
|
"GLIBC_2.1.3",
|
|
"GLIBC_2.1.4",
|
|
"GLIBC_2.2.1",
|
|
"GLIBC_2.2.2",
|
|
"GLIBC_2.2.3",
|
|
"GLIBC_2.2.4",
|
|
"GLIBC_2.2.5",
|
|
"GLIBC_2.2.6",
|
|
"GLIBC_2.3.2",
|
|
"GLIBC_2.3.3",
|
|
"GLIBC_2.3.4",
|
|
};
|
|
for (int i = 0; i < array_length (special_versions); ++i)
|
|
compare_vsyms_0 (libc_handle, name, special_versions[i], &found);
|
|
|
|
/* Iterate to an out-of-range version, to cover some unused symbols
|
|
as well. */
|
|
for (int minor_version = 0; minor_version <= __GLIBC_MINOR__ + 2;
|
|
++minor_version)
|
|
{
|
|
char version[30];
|
|
snprintf (version, sizeof (version), "GLIBC_%d.%d",
|
|
__GLIBC__, minor_version);
|
|
compare_vsyms_0 (libc_handle, name, version, &found);
|
|
}
|
|
|
|
if (!found)
|
|
FAIL_EXIT1 ("symbol %s not found at any version", name);
|
|
}
|
|
|
|
/* Run consistency checks for various symbols which usually have
|
|
multiple versions. */
|
|
static void
|
|
compare_vsyms (void)
|
|
{
|
|
/* The minor version loop in compare_vsyms_1 needs updating in case
|
|
we ever switch to glibc 3.0. */
|
|
if (__GLIBC__ != 2)
|
|
FAIL_EXIT1 ("unexpected glibc major version: %d", __GLIBC__);
|
|
|
|
/* __libc_dlvsym does not recognize the special RTLD_* handles, so
|
|
obtain an explicit handle for libc.so. */
|
|
void *libc_handle = xdlopen (LIBC_SO, RTLD_LAZY | RTLD_NOLOAD);
|
|
|
|
compare_vsyms_1 (libc_handle, "_sys_errlist");
|
|
compare_vsyms_1 (libc_handle, "_sys_siglist");
|
|
compare_vsyms_1 (libc_handle, "quick_exit");
|
|
|
|
xdlclose (libc_handle);
|
|
}
|