1 /* Test the mlock2 function.
2    Copyright (C) 2017-2021 Free Software Foundation, Inc.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <errno.h>
19 #include <stdio.h>
20 #include <support/check.h>
21 #include <support/xunistd.h>
22 #include <sys/mman.h>
23 
24 /* Allocate a page using mmap.  */
25 static void *
get_page(void)26 get_page (void)
27 {
28   return xmmap (NULL, 1, PROT_READ | PROT_WRITE,
29                 MAP_ANONYMOUS | MAP_PRIVATE, -1);
30 }
31 
32 static int
do_test(void)33 do_test (void)
34 {
35   /* Current kernels have a small reserve of locked memory, so this
36      test does not need any privileges to run.  */
37 
38   void *page = get_page ();
39   if (mlock (page, 1) != 0)
40     FAIL_EXIT1 ("mlock: %m\n");
41   xmunmap (page, 1);
42 
43   page = get_page ();
44   if (mlock2 (page, 1, 0) != 0)
45     /* Should be implemented using mlock if necessary.  */
46     FAIL_EXIT1 ("mlock2 (0): %m\n");
47   xmunmap (page, 1);
48 
49   page = get_page ();
50   int ret = mlock2 (page, 1, MLOCK_ONFAULT);
51   if (ret != 0)
52     {
53       TEST_VERIFY (ret == -1);
54       if (errno != EINVAL)
55         /* EINVAL means the system does not support the mlock2 system
56            call.  */
57         FAIL_EXIT1 ("mlock2 (0): %m\n");
58       else
59         puts ("warning: mlock2 system call not supported");
60     }
61   xmunmap (page, 1);
62 
63   return 0;
64 }
65 
66 #include <support/test-driver.c>
67