/*
 * Copyright 2002-2012 Haiku, Inc. All Rights Reserved.
 * Distributed under the terms of the MIT License.
 */
#ifndef _SYS_TIME_H
#define _SYS_TIME_H


#include <sys/types.h>


struct timeval {
        time_t          tv_sec;         /* seconds */
        suseconds_t     tv_usec;        /* microseconds */
};

#include <sys/select.h>
        /* circular dependency: fd_set needs to be defined and the
         * select prototype exported by this file, but <sys/select.h>
         * needs struct timeval.
         */

struct timezone {
        int tz_minuteswest;
        int tz_dsttime;
};

struct itimerval {
        struct timeval it_interval;
        struct timeval it_value;
};

#define ITIMER_REAL             1       /* real time */
#define ITIMER_VIRTUAL  2       /* process virtual time */
#define ITIMER_PROF             3       /* both */


#ifdef __cplusplus
extern "C" {
#endif

extern int      getitimer(int which, struct itimerval *value);
extern int      setitimer(int which, const struct itimerval *value, struct itimerval *oldValue);
extern int      gettimeofday(struct timeval *tv, void *tz);

extern int      utimes(const char *path, const struct timeval times[2]);
        /* legacy */

#ifdef __cplusplus
}
#endif

/* BSDish macros operating on timeval structs */
#define timeradd(a, b, res)                                                             \
        do {                                                                                            \
                (res)->tv_sec = (a)->tv_sec + (b)->tv_sec;              \
                (res)->tv_usec = (a)->tv_usec + (b)->tv_usec;   \
                if ((res)->tv_usec >= 1000000) {                                \
                        (res)->tv_usec -= 1000000;                                      \
                        (res)->tv_sec++;                                                        \
                }                                                                                               \
        } while (0)
#define timersub(a, b, res)                                                             \
        do {                                                                                            \
                (res)->tv_sec = (a)->tv_sec - (b)->tv_sec;              \
                (res)->tv_usec = (a)->tv_usec - (b)->tv_usec;   \
                if ((res)->tv_usec < 0) {                                               \
                        (res)->tv_usec += 1000000;                                      \
                        (res)->tv_sec--;                                                        \
                }                                                                                               \
        } while (0)
#define timerclear(a)   ((a)->tv_sec = (a)->tv_usec = 0)
#define timerisset(a)   ((a)->tv_sec != 0 || (a)->tv_usec != 0)
#define timercmp(a, b, cmp)     ((a)->tv_sec == (b)->tv_sec \
                ? (a)->tv_usec cmp (b)->tv_usec : (a)->tv_sec cmp (b)->tv_sec)

#endif  /* _SYS_TIME_H */