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/*
* Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
// Test that boottime value in /proc/uptime and CLOCK_BOOTTIME increment
// monotonically. We don't test idle time monotonicity due to broken iowait
// task counting, cf: comment above get_cpu_idle_time_us()
#undef NDEBUG
#include <assert.h>
#include <stdint.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "proc-uptime.h"
int main(void)
{
uint64_t start, u0, u1, c0, c1;
int fd;
fd = open("/proc/uptime", O_RDONLY);
assert(fd >= 0);
u0 = proc_uptime(fd);
start = u0;
c0 = clock_boottime();
do {
u1 = proc_uptime(fd);
c1 = clock_boottime();
/* Is /proc/uptime monotonic ? */
assert(u1 >= u0);
/* Is CLOCK_BOOTTIME monotonic ? */
assert(c1 >= c0);
/* Is CLOCK_BOOTTIME VS /proc/uptime monotonic ? */
assert(c0 >= u0);
u0 = u1;
c0 = c1;
} while (u1 - start < 100);
return 0;
}
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