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 /*
  42  * lhs < rhs:  return <0
  43  * lhs == rhs: return 0
  44  * lhs > rhs:  return >0
  45  */
  46 static inline int timespec_compare(struct timespec *lhs, struct timespec *rhs)
  47 {
  48         if (lhs->tv_sec < rhs->tv_sec)
  49                 return -1;
  50         if (lhs->tv_sec > rhs->tv_sec)
  51                 return 1;
  52         return lhs->tv_nsec - rhs->tv_nsec;
  53 }
  54
  55 static inline int timeval_compare(struct timeval *lhs, struct timeval *rhs)
  56 {
  57         if (lhs->tv_sec < rhs->tv_sec)
  58                 return -1;
  59         if (lhs->tv_sec > rhs->tv_sec)
  60                 return 1;
  61         return lhs->tv_usec - rhs->tv_usec;
  62 }
  63
  64 extern unsigned long mktime(const unsigned int year, const unsigned int mon,
  65                             const unsigned int day, const unsigned int hour,
  66                             const unsigned int min, const unsigned int sec);
  67
  68 extern void set_normalized_timespec(struct timespec *ts, time_t sec, long nsec);
  69
  70 /*
  71  * Returns true if the timespec is norm, false if denorm:
  72  */
  73 #define timespec_valid(ts) \
  74         (((ts)->tv_sec >= 0) && (((unsigned long) (ts)->tv_nsec) < NSEC_PER_SEC))
  75
  76 extern struct timespec xtime;
  77 extern struct timespec wall_to_monotonic;
  78 extern seqlock_t xtime_lock;
  79
  80 static inline unsigned long get_seconds(void)
  81 {
  82         return xtime.tv_sec;
  83 }
  84
  85 struct timespec current_kernel_time(void);
  86
  87 #define CURRENT_TIME            (current_kernel_time())
  88 #define CURRENT_TIME_SEC        ((struct timespec) { xtime.tv_sec, 0 })
  89
  90 extern void do_gettimeofday(struct timeval *tv);
  91 extern int do_settimeofday(struct timespec *tv);
  92 extern int do_sys_settimeofday(struct timespec *tv, struct timezone *tz);
  93 #define do_posix_clock_monotonic_gettime(ts) ktime_get_ts(ts)
  94 extern long do_utimes(int dfd, char __user *filename, struct timeval *times);
  95 struct itimerval;
  96 extern int do_setitimer(int which, struct itimerval *value,
  97                         struct itimerval *ovalue);
  98 extern unsigned int alarm_setitimer(unsigned int seconds);
  99 extern int do_getitimer(int which, struct itimerval *value);
 100 extern void getnstimeofday(struct timespec *tv);
 101
 102 extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
 103
 104 /**
 105  * timespec_to_ns - Convert timespec to nanoseconds
 106  * @ts:         pointer to the timespec variable to be converted
 107  *
 108  * Returns the scalar nanosecond representation of the timespec
 109  * parameter.
 110  */
 111 static inline s64 timespec_to_ns(const struct timespec *ts)
 112 {
 113         return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
 114 }
 115
 116 /**
 117  * timeval_to_ns - Convert timeval to nanoseconds
 118  * @ts:         pointer to the timeval variable to be converted
 119  *
 120  * Returns the scalar nanosecond representation of the timeval
 121  * parameter.
 122  */
 123 static inline s64 timeval_to_ns(const struct timeval *tv)
 124 {
 125         return ((s64) tv->tv_sec * NSEC_PER_SEC) +
 126                 tv->tv_usec * NSEC_PER_USEC;
 127 }
 128
 129 /**
 130  * ns_to_timespec - Convert nanoseconds to timespec
 131  * @nsec:       the nanoseconds value to be converted
 132  *
 133  * Returns the timespec representation of the nsec parameter.
 134  */
 135 extern struct timespec ns_to_timespec(const s64 nsec);
 136
 137 /**
 138  * ns_to_timeval - Convert nanoseconds to timeval
 139  * @nsec:       the nanoseconds value to be converted
 140  *
 141  * Returns the timeval representation of the nsec parameter.
 142  */
 143 extern struct timeval ns_to_timeval(const s64 nsec);
 144
 145 #endif /* __KERNEL__ */
 146
 147 #define NFDBITS                 __NFDBITS
 148
 149 #define FD_SETSIZE              __FD_SETSIZE
 150 #define FD_SET(fd,fdsetp)       __FD_SET(fd,fdsetp)
 151 #define FD_CLR(fd,fdsetp)       __FD_CLR(fd,fdsetp)
 152 #define FD_ISSET(fd,fdsetp)     __FD_ISSET(fd,fdsetp)
 153 #define FD_ZERO(fdsetp)         __FD_ZERO(fdsetp)
 154
 155 /*
 156  * Names of the interval timers, and structure
 157  * defining a timer setting:
 158  */
 159 #define ITIMER_REAL             0
 160 #define ITIMER_VIRTUAL          1
 161 #define ITIMER_PROF             2
 162
 163 struct itimerspec {
 164         struct timespec it_interval;    /* timer period */
 165         struct timespec it_value;       /* timer expiration */
 166 };
 167
 168 struct itimerval {
 169         struct timeval it_interval;     /* timer interval */
 170         struct timeval it_value;        /* current value */
 171 };
 172
 173 /*
 174  * The IDs of the various system clocks (for POSIX.1b interval timers):
 175  */
 176 #define CLOCK_REALTIME                  0
 177 #define CLOCK_MONOTONIC                 1
 178 #define CLOCK_PROCESS_CPUTIME_ID        2
 179 #define CLOCK_THREAD_CPUTIME_ID         3
 180
 181 /*
 182  * The IDs of various hardware clocks:
 183  */
 184 #define CLOCK_SGI_CYCLE                 10
 185 #define MAX_CLOCKS                      16
 186 #define CLOCKS_MASK                     (CLOCK_REALTIME | CLOCK_MONOTONIC)
 187 #define CLOCKS_MONO                     CLOCK_MONOTONIC
 188
 189 /*
 190  * The various flags for setting POSIX.1b interval timers:
 191  */
 192 #define TIMER_ABSTIME                   0x01
 193
 194 #endif