Merge tag 'trace-printf-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace...
[drm/drm-misc.git] / tools / testing / selftests / proc / proc-uptime.h
blob730cce4a3d73ec36ee4aec506c2778844bbc0b18
1 /*
2 * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
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.
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.
16 #undef NDEBUG
17 #include <assert.h>
18 #include <errno.h>
19 #include <string.h>
20 #include <stdlib.h>
21 #include <unistd.h>
22 #include <time.h>
24 #include "proc.h"
26 static uint64_t clock_boottime(void)
28 struct timespec ts;
29 int err;
31 err = clock_gettime(CLOCK_BOOTTIME, &ts);
32 assert(err >= 0);
34 return (ts.tv_sec * 100) + (ts.tv_nsec / 10000000);
37 static uint64_t proc_uptime(int fd)
39 uint64_t val1, val2;
40 char buf[64], *p;
41 ssize_t rv;
43 /* save "p < end" checks */
44 memset(buf, 0, sizeof(buf));
45 rv = pread(fd, buf, sizeof(buf), 0);
46 assert(0 <= rv && rv <= sizeof(buf));
47 buf[sizeof(buf) - 1] = '\0';
49 p = buf;
51 val1 = xstrtoull(p, &p);
52 assert(p[0] == '.');
53 assert('0' <= p[1] && p[1] <= '9');
54 assert('0' <= p[2] && p[2] <= '9');
55 assert(p[3] == ' ');
57 val2 = (p[1] - '0') * 10 + p[2] - '0';
59 return val1 * 100 + val2;