include/linux/time.h

   1 #ifndef _LINUX_TIME_H
   2 #define _LINUX_TIME_H
   3
   4 #include <linux/types.h>
   5
   6 #ifdef __KERNEL__
   7 # include <linux/seqlock.h>
   8 #endif
   9
  10 #ifndef _STRUCT_TIMESPEC
  11 #define _STRUCT_TIMESPEC
  12 struct timespec {
  13         time_t  tv_sec;         /* seconds */
  14         long    tv_nsec;        /* nanoseconds */
  15 };
  16 #endif
  17
  18 struct timeval {
  19         time_t          tv_sec;         /* seconds */
  20         suseconds_t     tv_usec;        /* microseconds */
  21 };
  22
  23 struct timezone {
  24         int     tz_minuteswest; /* minutes west of Greenwich */
  25         int     tz_dsttime;     /* type of dst correction */
  26 };
  27
  28 #ifdef __KERNEL__
  29
  30 /* Parameters used to convert the timespec values: */
  31 #define MSEC_PER_SEC            1000L
  32 #define USEC_PER_SEC            1000000L
  33 #define NSEC_PER_SEC            1000000000L
  34 #define NSEC_PER_USEC           1000L
  35
  36 static __inline__ int timespec_equal(struct timespec *a, struct timespec *b)
  37 {
  38         return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
  39 }
  40
  41 extern unsigned long mktime(const unsigned int year, const unsigned int mon,
  42                             const unsigned int day, const unsigned int hour,
  43                             const unsigned int min, const unsigned int sec);
  44
  45 extern void set_normalized_timespec(struct timespec *ts, time_t sec, long nsec);
  46
  47 /*
  48  * Returns true if the timespec is norm, false if denorm:
  49  */
  50 #define timespec_valid(ts) \
  51         (((ts)->tv_sec >= 0) && (((unsigned) (ts)->tv_nsec) < NSEC_PER_SEC))
  52
  53 /*
  54  * 64-bit nanosec type. Large enough to span 292+ years in nanosecond
  55  * resolution. Ought to be enough for a while.
  56  */
  57 typedef s64 nsec_t;
  58
  59 extern struct timespec xtime;
  60 extern struct timespec wall_to_monotonic;
  61 extern seqlock_t xtime_lock;
  62
  63 static inline unsigned long get_seconds(void)
  64 {
  65         return xtime.tv_sec;
  66 }
  67
  68 struct timespec current_kernel_time(void);
  69
  70 #define CURRENT_TIME            (current_kernel_time())
  71 #define CURRENT_TIME_SEC        ((struct timespec) { xtime.tv_sec, 0 })
  72
  73 extern void do_gettimeofday(struct timeval *tv);
  74 extern int do_settimeofday(struct timespec *tv);
  75 extern int do_sys_settimeofday(struct timespec *tv, struct timezone *tz);
  76 extern void clock_was_set(void); // call whenever the clock is set
  77 extern int do_posix_clock_monotonic_gettime(struct timespec *tp);
  78 extern long do_utimes(char __user *filename, struct timeval *times);
  79 struct itimerval;
  80 extern int do_setitimer(int which, struct itimerval *value,
  81                         struct itimerval *ovalue);
  82 extern int do_getitimer(int which, struct itimerval *value);
  83 extern void getnstimeofday(struct timespec *tv);
  84 extern void getnstimestamp(struct timespec *ts);
  85
  86 extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
  87
  88 /**
  89  * timespec_to_ns - Convert timespec to nanoseconds
  90  * @ts:         pointer to the timespec variable to be converted
  91  *
  92  * Returns the scalar nanosecond representation of the timespec
  93  * parameter.
  94  */
  95 static inline nsec_t timespec_to_ns(const struct timespec *ts)
  96 {
  97         return ((nsec_t) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
  98 }
  99
 100 /**
 101  * timeval_to_ns - Convert timeval to nanoseconds
 102  * @ts:         pointer to the timeval variable to be converted
 103  *
 104  * Returns the scalar nanosecond representation of the timeval
 105  * parameter.
 106  */
 107 static inline nsec_t timeval_to_ns(const struct timeval *tv)
 108 {
 109         return ((nsec_t) tv->tv_sec * NSEC_PER_SEC) +
 110                 tv->tv_usec * NSEC_PER_USEC;
 111 }
 112
 113 /**
 114  * ns_to_timespec - Convert nanoseconds to timespec
 115  * @nsec:       the nanoseconds value to be converted
 116  *
 117  * Returns the timespec representation of the nsec parameter.
 118  */
 119 extern struct timespec ns_to_timespec(const nsec_t nsec);
 120
 121 /**
 122  * ns_to_timeval - Convert nanoseconds to timeval
 123  * @nsec:       the nanoseconds value to be converted
 124  *
 125  * Returns the timeval representation of the nsec parameter.
 126  */
 127 extern struct timeval ns_to_timeval(const nsec_t nsec);
 128
 129 #endif /* __KERNEL__ */
 130
 131 #define NFDBITS                 __NFDBITS
 132
 133 #define FD_SETSIZE              __FD_SETSIZE
 134 #define FD_SET(fd,fdsetp)       __FD_SET(fd,fdsetp)
 135 #define FD_CLR(fd,fdsetp)       __FD_CLR(fd,fdsetp)
 136 #define FD_ISSET(fd,fdsetp)     __FD_ISSET(fd,fdsetp)
 137 #define FD_ZERO(fdsetp)         __FD_ZERO(fdsetp)
 138
 139 /*
 140  * Names of the interval timers, and structure
 141  * defining a timer setting:
 142  */
 143 #define ITIMER_REAL             0
 144 #define ITIMER_VIRTUAL          1
 145 #define ITIMER_PROF             2
 146
 147 struct itimerspec {
 148         struct timespec it_interval;    /* timer period */
 149         struct timespec it_value;       /* timer expiration */
 150 };
 151
 152 struct itimerval {
 153         struct timeval it_interval;     /* timer interval */
 154         struct timeval it_value;        /* current value */
 155 };
 156
 157 /*
 158  * The IDs of the various system clocks (for POSIX.1b interval timers):
 159  */
 160 #define CLOCK_REALTIME                  0
 161 #define CLOCK_MONOTONIC                 1
 162 #define CLOCK_PROCESS_CPUTIME_ID        2
 163 #define CLOCK_THREAD_CPUTIME_ID         3
 164
 165 /*
 166  * The IDs of various hardware clocks:
 167  */
 168 #define CLOCK_SGI_CYCLE                 10
 169 #define MAX_CLOCKS                      16
 170 #define CLOCKS_MASK                     (CLOCK_REALTIME | CLOCK_MONOTONIC)
 171 #define CLOCKS_MONO                     CLOCK_MONOTONIC
 172
 173 /*
 174  * The various flags for setting POSIX.1b interval timers:
 175  */
 176 #define TIMER_ABSTIME                   0x01
 177
 178 #endif