2 * util/timeval_func.c - helpers to work with struct timeval values.
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39 * This file contains helpers to manipulate struct timeval values.
43 #include "timeval_func.h"
45 /** subtract timers and the values do not overflow or become negative */
47 timeval_subtract(struct timeval* d, const struct timeval* end, const struct timeval* start)
50 time_t end_usec = end->tv_usec;
51 d->tv_sec = end->tv_sec - start->tv_sec;
52 if(end_usec < start->tv_usec) {
56 d->tv_usec = end_usec - start->tv_usec;
60 /** add timers and the values do not overflow or become negative */
62 timeval_add(struct timeval* d, const struct timeval* add)
65 d->tv_sec += add->tv_sec;
66 d->tv_usec += add->tv_usec;
67 if(d->tv_usec >= 1000000 ) {
68 d->tv_usec -= 1000000;
74 /** divide sum of timers to get average */
76 timeval_divide(struct timeval* avg, const struct timeval* sum, long long d)
85 avg->tv_sec = sum->tv_sec / d;
86 avg->tv_usec = sum->tv_usec / d;
87 /* handle fraction from seconds divide */
88 leftover = sum->tv_sec - avg->tv_sec*d;
91 avg->tv_usec += (((long long)leftover)*((long long)1000000))/d;
99 /** histogram compare of time values */
101 timeval_smaller(const struct timeval* x, const struct timeval* y)
104 if(x->tv_sec < y->tv_sec)
106 else if(x->tv_sec == y->tv_sec) {
107 if(x->tv_usec <= y->tv_usec)