1 /*
2 * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
3 *
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16 // Test that values in /proc/uptime increment monotonically.
17 #undef NDEBUG
18 #include <assert.h>
19 #include <stdint.h>
20 #include <sys/types.h>
21 #include <sys/stat.h>
22 #include <fcntl.h>
23
24 #include "proc-uptime.h"
25
26 int main(void)
27 {
28 uint64_t start, u0, u1, i0, i1;
29 int fd;
30
31 fd = open("/proc/uptime", O_RDONLY);
32 assert(fd >= 0);
33
34 proc_uptime(fd, &u0, &i0);
35 start = u0;
36 do {
37 proc_uptime(fd, &u1, &i1);
38 assert(u1 >= u0);
39 assert(i1 >= i0);
40 u0 = u1;
41 i0 = i1;
42 } while (u1 - start < 100);
43
44 return 0;
45 }