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 /*
  77  * 64-bit nanosec type. Large enough to span 292+ years in nanosecond
  78  * resolution. Ought to be enough for a while.
  79  */
  80 typedef s64 nsec_t;
  81
  82 extern struct timespec xtime;
  83 extern struct timespec wall_to_monotonic;
  84 extern seqlock_t xtime_lock;
  85
  86 static inline unsigned long get_seconds(void)
  87 {
  88         return xtime.tv_sec;
  89 }
  90
  91 struct timespec current_kernel_time(void);
  92
  93 #define CURRENT_TIME            (current_kernel_time())
  94 #define CURRENT_TIME_SEC        ((struct timespec) { xtime.tv_sec, 0 })
  95
  96 extern void do_gettimeofday(struct timeval *tv);
  97 extern int do_settimeofday(struct timespec *tv);
  98 extern int do_sys_settimeofday(struct timespec *tv, struct timezone *tz);
  99 #define do_posix_clock_monotonic_gettime(ts) ktime_get_ts(ts)
 100 extern long do_utimes(int dfd, char __user *filename, struct timeval *times);
 101 struct itimerval;
 102 extern int do_setitimer(int which, struct itimerval *value,
 103                         struct itimerval *ovalue);
 104 extern int do_getitimer(int which, struct itimerval *value);
 105 extern void getnstimeofday(struct timespec *tv);
 106
 107 extern struct timespec timespec_trunc(struct timespec t, unsigned gran);
 108
 109 /**
 110  * timespec_to_ns - Convert timespec to nanoseconds
 111  * @ts:         pointer to the timespec variable to be converted
 112  *
 113  * Returns the scalar nanosecond representation of the timespec
 114  * parameter.
 115  */
 116 static inline nsec_t timespec_to_ns(const struct timespec *ts)
 117 {
 118         return ((nsec_t) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
 119 }
 120
 121 /**
 122  * timeval_to_ns - Convert timeval to nanoseconds
 123  * @ts:         pointer to the timeval variable to be converted
 124  *
 125  * Returns the scalar nanosecond representation of the timeval
 126  * parameter.
 127  */
 128 static inline nsec_t timeval_to_ns(const struct timeval *tv)
 129 {
 130         return ((nsec_t) tv->tv_sec * NSEC_PER_SEC) +
 131                 tv->tv_usec * NSEC_PER_USEC;
 132 }
 133
 134 /**
 135  * ns_to_timespec - Convert nanoseconds to timespec
 136  * @nsec:       the nanoseconds value to be converted
 137  *
 138  * Returns the timespec representation of the nsec parameter.
 139  */
 140 extern struct timespec ns_to_timespec(const nsec_t nsec);
 141
 142 /**
 143  * ns_to_timeval - Convert nanoseconds to timeval
 144  * @nsec:       the nanoseconds value to be converted
 145  *
 146  * Returns the timeval representation of the nsec parameter.
 147  */
 148 extern struct timeval ns_to_timeval(const nsec_t nsec);
 149
 150 #endif /* __KERNEL__ */
 151
 152 #define NFDBITS                 __NFDBITS
 153
 154 #define FD_SETSIZE              __FD_SETSIZE
 155 #define FD_SET(fd,fdsetp)       __FD_SET(fd,fdsetp)
 156 #define FD_CLR(fd,fdsetp)       __FD_CLR(fd,fdsetp)
 157 #define FD_ISSET(fd,fdsetp)     __FD_ISSET(fd,fdsetp)
 158 #define FD_ZERO(fdsetp)         __FD_ZERO(fdsetp)
 159
 160 /*
 161  * Names of the interval timers, and structure
 162  * defining a timer setting:
 163  */
 164 #define ITIMER_REAL             0
 165 #define ITIMER_VIRTUAL          1
 166 #define ITIMER_PROF             2
 167
 168 struct itimerspec {
 169         struct timespec it_interval;    /* timer period */
 170         struct timespec it_value;       /* timer expiration */
 171 };
 172
 173 struct itimerval {
 174         struct timeval it_interval;     /* timer interval */
 175         struct timeval it_value;        /* current value */
 176 };
 177
 178 /*
 179  * The IDs of the various system clocks (for POSIX.1b interval timers):
 180  */
 181 #define CLOCK_REALTIME                  0
 182 #define CLOCK_MONOTONIC                 1
 183 #define CLOCK_PROCESS_CPUTIME_ID        2
 184 #define CLOCK_THREAD_CPUTIME_ID         3
 185
 186 /*
 187  * The IDs of various hardware clocks:
 188  */
 189 #define CLOCK_SGI_CYCLE                 10
 190 #define MAX_CLOCKS                      16
 191 #define CLOCKS_MASK                     (CLOCK_REALTIME | CLOCK_MONOTONIC)
 192 #define CLOCKS_MONO                     CLOCK_MONOTONIC
 193
 194 /*
 195  * The various flags for setting POSIX.1b interval timers:
 196  */
 197 #define TIMER_ABSTIME                   0x01
 198
 199 #endif