timer/timespec.c
Zack Buhman 8c1c1e97f6 duplicate send, resend, ack
The 'software' renderer is now explicitly requested.
2024-06-26 02:44:07 -05:00

58 lines
1.3 KiB
C

#include <time.h>
#include <stdio.h>
#include <assert.h>
#include <stdint.h>
struct timespec timespec_sub(const struct timespec * a,
const struct timespec * b)
{
struct timespec c = {
.tv_sec = a->tv_sec - b->tv_sec,
.tv_nsec = a->tv_nsec - b->tv_nsec
};
if (c.tv_nsec < 0) {
c.tv_nsec += 1000000000;
c.tv_sec -= 1;
}
return c;
}
struct timespec timespec_add(const struct timespec * a,
const struct timespec * b)
{
struct timespec c = {
.tv_sec = a->tv_sec + b->tv_sec,
.tv_nsec = a->tv_nsec + b->tv_nsec
};
int64_t rem = c.tv_nsec / 1000000000;
c.tv_nsec = c.tv_nsec % 1000000000;
c.tv_sec += rem;
return c;
}
struct timespec timespec_div(const struct timespec * a,
int n)
{
int64_t rem = a->tv_sec % n;
struct timespec c = {
.tv_sec = a->tv_sec / n,
.tv_nsec = (a->tv_nsec / n) + (rem * 1000000000 / n)
};
assert(c.tv_nsec < 1000000000);
return c;
}
struct timespec timespec_average(const struct timespec * ts,
int length)
{
struct timespec c = {0};
for (int i = 0; i < length; i++) {
c = timespec_add(&c, &ts[i]);
//printf("rtt[%d]: %ld.%09ld\n", i, ts[i].tv_sec, ts[i].tv_nsec);
}
struct timespec d = timespec_div(&c, length);
//printf("average: %ld.%09ld\n", d.tv_sec, d.tv_nsec);
return d;
}