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1/*2 * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>3 *4 * Permission to use, copy, modify, and distribute this software for any5 * purpose with or without fee is hereby granted, provided that the above6 * copyright notice and this permission notice appear in all copies.7 *8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.15 */16#undef NDEBUG17#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 26static 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 37static 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('0' <= p[1] && p[1] <= '9');54 assert('0' <= p[2] && p[2] <= '9');55 assert(p[3] == ' ');56 57 val2 = (p[1] - '0') * 10 + p[2] - '0';58 59 return val1 * 100 + val2;60}61