1/* Make sure dlopen/dlclose are not marked as leaf functions.
2
3 Copyright (C) 2013-2022 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20/* The bug-dl-leaf.c file will call our lib_main directly. We do this to
21 keep things simple -- no need to use --export-dynamic with the linker
22 or build the main ELF as a PIE.
23
24 The lib_main func will modify some of its state while dlopening and
25 dlclosing the bug-dl-leaf-lib-cb.so library. The constructors and
26 destructors in that library will call back into this library to also
27 muck with state (the check_val_xxx funcs).
28
29 If dlclose/dlopen are marked as "leaf" functions, then with newer
30 versions of gcc, the state modification won't work correctly. */
31
32#include <assert.h>
33#include <dlfcn.h>
34
35static int val = 1;
36static int called = 0;
37
38void check_val_init (void)
39{
40 called = 1;
41 assert (val == 2);
42}
43
44void check_val_fini (void)
45{
46 called = 2;
47 assert (val == 4);
48}
49
50int lib_main (void)
51{
52 int ret __attribute__ ((unused));
53 void *hdl;
54
55 /* Make sure the constructor sees the updated val. */
56 val = 2;
57 hdl = dlopen (file: "bug-dl-leaf-lib-cb.so", RTLD_GLOBAL | RTLD_LAZY);
58 val = 3;
59 assert (hdl);
60 assert (called == 1);
61
62 /* Make sure the destructor sees the updated val. */
63 val = 4;
64 ret = dlclose (handle: hdl);
65 val = 5;
66 assert (ret == 0);
67 assert (called == 2);
68
69 return !val;
70}
71

source code of glibc/dlfcn/bug-dl-leaf-lib.c