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 #define do_posix_clock_monotonic_gettime(ts) ktime_get_ts(ts)
  77 extern long do_utimes(int dfd, char __user *filename, struct timeval *times);
  78 struct itimerval;
  79 extern int do_setitimer(int which, struct itimerval *value,
  80                         struct itimerval *ovalue);
  81 extern int do_getitimer(int which, struct itimerval *value);
  82 extern void getnstimeofday(struct timespec *tv);
  83
  84 extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
  85
  86 /**
  87  * timespec_to_ns - Convert timespec to nanoseconds
  88  * @ts:         pointer to the timespec variable to be converted
  89  *
  90  * Returns the scalar nanosecond representation of the timespec
  91  * parameter.
  92  */
  93 static inline nsec_t timespec_to_ns(const struct timespec *ts)
  94 {
  95         return ((nsec_t) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
  96 }
  97
  98 /**
  99  * timeval_to_ns - Convert timeval to nanoseconds
 100  * @ts:         pointer to the timeval variable to be converted
 101  *
 102  * Returns the scalar nanosecond representation of the timeval
 103  * parameter.
 104  */
 105 static inline nsec_t timeval_to_ns(const struct timeval *tv)
 106 {
 107         return ((nsec_t) tv->tv_sec * NSEC_PER_SEC) +
 108                 tv->tv_usec * NSEC_PER_USEC;
 109 }
 110
 111 /**
 112  * ns_to_timespec - Convert nanoseconds to timespec
 113  * @nsec:       the nanoseconds value to be converted
 114  *
 115  * Returns the timespec representation of the nsec parameter.
 116  */
 117 extern struct timespec ns_to_timespec(const nsec_t nsec);
 118
 119 /**
 120  * ns_to_timeval - Convert nanoseconds to timeval
 121  * @nsec:       the nanoseconds value to be converted
 122  *
 123  * Returns the timeval representation of the nsec parameter.
 124  */
 125 extern struct timeval ns_to_timeval(const nsec_t nsec);
 126
 127 #endif /* __KERNEL__ */
 128
 129 #define NFDBITS                 __NFDBITS
 130
 131 #define FD_SETSIZE              __FD_SETSIZE
 132 #define FD_SET(fd,fdsetp)       __FD_SET(fd,fdsetp)
 133 #define FD_CLR(fd,fdsetp)       __FD_CLR(fd,fdsetp)
 134 #define FD_ISSET(fd,fdsetp)     __FD_ISSET(fd,fdsetp)
 135 #define FD_ZERO(fdsetp)         __FD_ZERO(fdsetp)
 136
 137 /*
 138  * Names of the interval timers, and structure
 139  * defining a timer setting:
 140  */
 141 #define ITIMER_REAL             0
 142 #define ITIMER_VIRTUAL          1
 143 #define ITIMER_PROF             2
 144
 145 struct itimerspec {
 146         struct timespec it_interval;    /* timer period */
 147         struct timespec it_value;       /* timer expiration */
 148 };
 149
 150 struct itimerval {
 151         struct timeval it_interval;     /* timer interval */
 152         struct timeval it_value;        /* current value */
 153 };
 154
 155 /*
 156  * The IDs of the various system clocks (for POSIX.1b interval timers):
 157  */
 158 #define CLOCK_REALTIME                  0
 159 #define CLOCK_MONOTONIC                 1
 160 #define CLOCK_PROCESS_CPUTIME_ID        2
 161 #define CLOCK_THREAD_CPUTIME_ID         3
 162
 163 /*
 164  * The IDs of various hardware clocks:
 165  */
 166 #define CLOCK_SGI_CYCLE                 10
 167 #define MAX_CLOCKS                      16
 168 #define CLOCKS_MASK                     (CLOCK_REALTIME | CLOCK_MONOTONIC)
 169 #define CLOCKS_MONO                     CLOCK_MONOTONIC
 170
 171 /*
 172  * The various flags for setting POSIX.1b interval timers:
 173  */
 174 #define TIMER_ABSTIME                   0x01
 175
 176 #endif