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 #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>
23
24 #include "proc.h"
25
26 static uint64_t clock_boottime(void)
27 {
28 struct timespec ts;
29 int err;
30
31 err = clock_gettime(CLOCK_BOOTTIME, &ts);
32 assert(err >= 0);
33
34 return (ts.tv_sec * 100) + (ts.tv_nsec / 10000000);
35 }
36
37 static uint64_t proc_uptime(int fd)
38 {
39 uint64_t val1, val2;
40 char buf[64], *p;
41 ssize_t rv;
42
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';
48
49 p = buf;
50
51 val1 = xstrtoull(p, &p);
52 assert(p[0] == '.');
53 assert('' <= p[1] && p[1] <= '9');
54 assert('' <= p[2] && p[2] <= '9');
55 assert(p[3] == ' ');
56
57 val2 = (p[1] - '') * 10 + p[2] - '';
58
59 return val1 * 100 + val2;
60 }
61
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.