// -*- c-file-style: "bsd" -*-

#ifndef _LIB_TIMEVAL_H_
#define _LIB_TIMEVAL_H_

#include <sys/time.h>
#include <time.h>               /* strftime */
#include <stdlib.h>             /* malloc */
#include <stdio.h>              /* sprintf */
#include <string.h>

static inline struct timeval
timeval_sub(struct timeval a, struct timeval b) {
        struct timeval result;
        
        if (a.tv_usec < b.tv_usec) {
                result.tv_sec = a.tv_sec - b.tv_sec - 1;
                result.tv_usec = a.tv_usec + 1000000 - b.tv_usec;
        } else {
                result.tv_sec = a.tv_sec - b.tv_sec;
                result.tv_usec = a.tv_usec - b.tv_usec;
        }
        return result;
};

static inline bool
timeval_lessthan(struct timeval a, struct timeval b) {
        return ((a.tv_sec < b.tv_sec) ||
                ((a.tv_sec == b.tv_sec) &&
                 (a.tv_usec < b.tv_usec)));
};

static inline struct timeval
Timeval_FromSecs(double secs)
{
        struct timeval res = {
                .tv_sec = secs,
                .tv_usec = (secs - (long long)secs) * 1000000,
        };
        return res;
}

#define FMT_TIMEVAL_ABS "%s"
#define XVA_TIMEVAL_ABS(t) Message_DFree(Timeval_FmtAbs(t))

static inline char *
Timeval_FmtAbs(struct timeval tv)
{
        static const int LEN = 32;
        char *buf = malloc(LEN);
        if (!buf)
                return NULL;
        strftime(buf, LEN, "%H:%M:%S", localtime(&tv.tv_sec));
        sprintf(buf + strlen(buf), ":%06ld", tv.tv_usec);
        return buf;
}

#endif