include/time.h

   1 /* Copyright (C) 1991-2003,2006,2009 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 /*
  19  *      ISO C99 Standard: 7.23 Date and time    <time.h>
  20  */
  21
  22 #ifndef _TIME_H
  23
  24 #if (! defined __need_time_t && !defined __need_clock_t && \
  25      ! defined __need_timespec)
  26 # define _TIME_H        1
  27 # include <features.h>
  28
  29 __BEGIN_DECLS
  30
  31 #endif
  32
  33 #ifdef  _TIME_H
  34 /* Get size_t and NULL from <stddef.h>.  */
  35 # define __need_size_t
  36 # define __need_NULL
  37 # include <stddef.h>
  38
  39 /* This defines CLOCKS_PER_SEC, which is the number of processor clock
  40    ticks per second.  */
  41 # include <bits/time.h>
  42
  43 /* This is the obsolete POSIX.1-1988 name for the same constant.  */
  44 # if !defined __STRICT_ANSI__ && !defined __USE_XOPEN2K
  45 #  ifndef CLK_TCK
  46 #   define CLK_TCK      CLOCKS_PER_SEC
  47 #  endif
  48 # endif
  49
  50 #endif /* <time.h> included.  */
  51
  52 #if !defined __clock_t_defined && (defined _TIME_H || defined __need_clock_t)
  53 # define __clock_t_defined      1
  54
  55 # include <bits/types.h>
  56
  57 __BEGIN_NAMESPACE_STD
  58 /* Returned by `clock'.  */
  59 typedef __clock_t clock_t;
  60 __END_NAMESPACE_STD
  61 #if defined __USE_XOPEN || defined __USE_POSIX || defined __USE_MISC
  62 __USING_NAMESPACE_STD(clock_t)
  63 #endif
  64
  65 #endif /* clock_t not defined and <time.h> or need clock_t.  */
  66 #undef  __need_clock_t
  67
  68 #if !defined __time_t_defined && (defined _TIME_H || defined __need_time_t)
  69 # define __time_t_defined       1
  70
  71 # include <bits/types.h>
  72
  73 __BEGIN_NAMESPACE_STD
  74 /* Returned by `time'.  */
  75 typedef __time_t time_t;
  76 __END_NAMESPACE_STD
  77 #if defined __USE_POSIX || defined __USE_MISC || defined __USE_SVID
  78 __USING_NAMESPACE_STD(time_t)
  79 #endif
  80
  81 #endif /* time_t not defined and <time.h> or need time_t.  */
  82 #undef  __need_time_t
  83
  84 #if !defined __clockid_t_defined && \
  85    ((defined _TIME_H && defined __USE_POSIX199309) || defined __need_clockid_t)
  86 # define __clockid_t_defined    1
  87
  88 # include <bits/types.h>
  89
  90 /* Clock ID used in clock and timer functions.  */
  91 typedef __clockid_t clockid_t;
  92
  93 #endif /* clockid_t not defined and <time.h> or need clockid_t.  */
  94 #undef  __clockid_time_t
  95
  96 #if !defined __timer_t_defined && \
  97     ((defined _TIME_H && defined __USE_POSIX199309) || defined __need_timer_t)
  98 # define __timer_t_defined      1
  99
 100 # include <bits/types.h>
 101
 102 /* Timer ID returned by `timer_create'.  */
 103 typedef __timer_t timer_t;
 104
 105 #endif /* timer_t not defined and <time.h> or need timer_t.  */
 106 #undef  __need_timer_t
 107
 108
 109 #if !defined __timespec_defined &&                              \
 110     ((defined _TIME_H &&                                        \
 111       (defined __USE_POSIX199309 || defined __USE_MISC)) ||     \
 112       defined __need_timespec)
 113 # define __timespec_defined     1
 114
 115 # include <bits/types.h>        /* This defines __time_t for us.  */
 116
 117 /* POSIX.1b structure for a time value.  This is like a `struct timeval' but
 118    has nanoseconds instead of microseconds.  */
 119 struct timespec
 120   {
 121     __time_t tv_sec;            /* Seconds.  */
 122     long int tv_nsec;           /* Nanoseconds.  */
 123   };
 124
 125 #endif /* timespec not defined and <time.h> or need timespec.  */
 126 #undef  __need_timespec
 127
 128
 129 #ifdef  _TIME_H
 130 __BEGIN_NAMESPACE_STD
 131 /* Used by other time functions.  */
 132 struct tm
 133 {
 134   int tm_sec;                   /* Seconds.     [0-60] (1 leap second) */
 135   int tm_min;                   /* Minutes.     [0-59] */
 136   int tm_hour;                  /* Hours.       [0-23] */
 137   int tm_mday;                  /* Day.         [1-31] */
 138   int tm_mon;                   /* Month.       [0-11] */
 139   int tm_year;                  /* Year - 1900.  */
 140   int tm_wday;                  /* Day of week. [0-6] */
 141   int tm_yday;                  /* Days in year.[0-365] */
 142   int tm_isdst;                 /* DST.         [-1/0/1]*/
 143
 144 #ifdef __UCLIBC_HAS_TM_EXTENSIONS__
 145 #ifdef  __USE_BSD
 146   long int tm_gmtoff;           /* Seconds east of UTC.  */
 147   const char *tm_zone;  /* Timezone abbreviation.  */
 148 #else
 149   long int __tm_gmtoff;         /* Seconds east of UTC.  */
 150   const char *__tm_zone;        /* Timezone abbreviation.  */
 151 #endif
 152 #endif /* __UCLIBC_HAS_TM_EXTENSIONS__ */
 153 };
 154 __END_NAMESPACE_STD
 155 #if defined __USE_XOPEN || defined __USE_POSIX || defined __USE_MISC
 156 __USING_NAMESPACE_STD(tm)
 157 #endif
 158
 159
 160 #ifdef __USE_POSIX199309
 161 /* POSIX.1b structure for timer start values and intervals.  */
 162 struct itimerspec
 163   {
 164     struct timespec it_interval;
 165     struct timespec it_value;
 166   };
 167
 168 /* We can use a simple forward declaration.  */
 169 struct sigevent;
 170
 171 #endif  /* POSIX.1b */
 172
 173 #ifdef __USE_XOPEN2K
 174 # ifndef __pid_t_defined
 175 typedef __pid_t pid_t;
 176 #  define __pid_t_defined
 177 # endif
 178 #endif
 179
 180
 181 __BEGIN_NAMESPACE_STD
 182 /* Time used by the program so far (user time + system time).
 183    The result / CLOCKS_PER_SECOND is program time in seconds.  */
 184 extern clock_t clock (void) __THROW;
 185
 186 /* Return the current time and put it in *TIMER if TIMER is not NULL.  */
 187 extern time_t time (time_t *__timer) __THROW;
 188 libc_hidden_proto(time)
 189
 190 #ifdef __UCLIBC_HAS_FLOATS__
 191 /* Return the difference between TIME1 and TIME0.  */
 192 extern double difftime (time_t __time1, time_t __time0)
 193      __THROW __attribute__ ((__const__));
 194 #endif /* __UCLIBC_HAS_FLOATS__ */
 195
 196 #ifdef _LIBC
 197 # define CLOCK_IDFIELD_SIZE     3
 198 #endif
 199
 200 /* Return the `time_t' representation of TP and normalize TP.  */
 201 extern time_t mktime (struct tm *__tp) __THROW;
 202
 203
 204 /* Format TP into S according to FORMAT.
 205    Write no more than MAXSIZE characters and return the number
 206    of characters written, or 0 if it would exceed MAXSIZE.  */
 207 extern size_t strftime (char *__restrict __s, size_t __maxsize,
 208                         const char *__restrict __format,
 209                         const struct tm *__restrict __tp) __THROW;
 210 __END_NAMESPACE_STD
 211
 212 # ifdef __USE_XOPEN
 213 /* Parse S according to FORMAT and store binary time information in TP.
 214    The return value is a pointer to the first unparsed character in S.  */
 215 extern char *strptime (const char *__restrict __s,
 216                        const char *__restrict __fmt, struct tm *__tp)
 217      __THROW;
 218 # endif
 219
 220 #ifdef __UCLIBC_HAS_XLOCALE__
 221 # ifdef __USE_XOPEN2K8
 222 /* Similar to the two functions above but take the information from
 223    the provided locale and not the global locale.  */
 224 # include <xlocale.h>
 225
 226 extern size_t strftime_l (char *__restrict __s, size_t __maxsize,
 227                           const char *__restrict __format,
 228                           const struct tm *__restrict __tp,
 229                           __locale_t __loc) __THROW;
 230 libc_hidden_proto(strftime_l)
 231 # endif
 232
 233 # ifdef __USE_GNU
 234 extern char *strptime_l (const char *__restrict __s,
 235                          const char *__restrict __fmt, struct tm *__tp,
 236                          __locale_t __loc) __THROW;
 237 libc_hidden_proto(strptime_l)
 238 # endif
 239 #endif
 240
 241
 242 __BEGIN_NAMESPACE_STD
 243 /* Return the `struct tm' representation of *TIMER
 244    in Universal Coordinated Time (aka Greenwich Mean Time).  */
 245 extern struct tm *gmtime (const time_t *__timer) __THROW;
 246
 247 /* Return the `struct tm' representation
 248    of *TIMER in the local timezone.  */
 249 extern struct tm *localtime (const time_t *__timer) __THROW;
 250 libc_hidden_proto(localtime)
 251 __END_NAMESPACE_STD
 252
 253 # if defined __USE_POSIX || defined __USE_MISC
 254 /* Return the `struct tm' representation of *TIMER in UTC,
 255    using *TP to store the result.  */
 256 extern struct tm *gmtime_r (const time_t *__restrict __timer,
 257                             struct tm *__restrict __tp) __THROW;
 258
 259 /* Return the `struct tm' representation of *TIMER in local time,
 260    using *TP to store the result.  */
 261 extern struct tm *localtime_r (const time_t *__restrict __timer,
 262                                struct tm *__restrict __tp) __THROW;
 263 libc_hidden_proto(localtime_r)
 264 # endif /* POSIX or misc */
 265
 266 __BEGIN_NAMESPACE_STD
 267 /* Return a string of the form "Day Mon dd hh:mm:ss yyyy\n"
 268    that is the representation of TP in this format.  */
 269 extern char *asctime (const struct tm *__tp) __THROW;
 270 libc_hidden_proto(asctime)
 271
 272 /* Equivalent to `asctime (localtime (timer))'.  */
 273 extern char *ctime (const time_t *__timer) __THROW;
 274 libc_hidden_proto(ctime)
 275 __END_NAMESPACE_STD
 276
 277 # if defined __USE_POSIX || defined __USE_MISC
 278 /* Reentrant versions of the above functions.  */
 279
 280 /* Return in BUF a string of the form "Day Mon dd hh:mm:ss yyyy\n"
 281    that is the representation of TP in this format.  */
 282 extern char *asctime_r (const struct tm *__restrict __tp,
 283                         char *__restrict __buf) __THROW;
 284 libc_hidden_proto(asctime_r)
 285
 286 /* Equivalent to `asctime_r (localtime_r (timer, *TMP*), buf)'.  */
 287 extern char *ctime_r (const time_t *__restrict __timer,
 288                       char *__restrict __buf) __THROW;
 289 # endif /* POSIX or misc */
 290
 291 # ifdef __USE_POSIX
 292 /* Same as above.  */
 293 extern char *tzname[2];
 294
 295 /* Set time conversion information from the TZ environment variable.
 296    If TZ is not defined, a locale-dependent default is used.  */
 297 extern void tzset (void) __THROW;
 298 libc_hidden_proto(tzset)
 299 # endif
 300
 301 # if defined __USE_SVID || defined __USE_XOPEN
 302 extern int daylight;
 303 extern long int timezone;
 304 # endif
 305
 306 # ifdef __USE_SVID
 307 /* Set the system time to *WHEN.
 308    This call is restricted to the superuser.  */
 309 extern int stime (const time_t *__when) __THROW;
 310 libc_hidden_proto(stime)
 311 # endif
 312
 313
 314 /* Nonzero if YEAR is a leap year (every 4 years,
 315    except every 100th isn't, and every 400th is).  */
 316 # define __isleap(year) \
 317   ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
 318
 319
 320 # ifdef __USE_MISC
 321 /* Miscellaneous functions many Unices inherited from the public domain
 322    localtime package.  These are included only for compatibility.  */
 323
 324 /* Like `mktime', but for TP represents Universal Time, not local time.  */
 325 extern time_t timegm (struct tm *__tp) __THROW;
 326
 327 /* Another name for `mktime'.  */
 328 extern time_t timelocal (struct tm *__tp) __THROW;
 329
 330 /* Return the number of days in YEAR.  */
 331 extern int dysize (int __year) __THROW  __attribute__ ((__const__));
 332 # endif
 333
 334
 335 # ifdef __USE_POSIX199309
 336 #  if defined __UCLIBC_HAS_REALTIME__
 337 /* Pause execution for a number of nanoseconds.
 338
 339    This function is a cancellation point and therefore not marked with
 340    __THROW.  */
 341 extern int nanosleep (const struct timespec *__requested_time,
 342                       struct timespec *__remaining);
 343 libc_hidden_proto(nanosleep)
 344
 345
 346 /* Get resolution of clock CLOCK_ID.  */
 347 extern int clock_getres (clockid_t __clock_id, struct timespec *__res) __THROW;
 348 libc_hidden_proto(clock_getres)
 349
 350 /* Get current value of clock CLOCK_ID and store it in TP.  */
 351 extern int clock_gettime (clockid_t __clock_id, struct timespec *__tp) __THROW;
 352
 353 /* Set clock CLOCK_ID to value TP.  */
 354 extern int clock_settime (clockid_t __clock_id, const struct timespec *__tp)
 355      __THROW;
 356 #  endif /* __UCLIBC_HAS_REALTIME__ */
 357
 358 #  if defined __USE_XOPEN2K && defined __UCLIBC_HAS_ADVANCED_REALTIME__
 359 #   ifdef __UCLIBC_HAS_THREADS_NATIVE__
 360 /* High-resolution sleep with the specified clock.
 361
 362    This function is a cancellation point and therefore not marked with
 363    __THROW.  */
 364 extern int clock_nanosleep (clockid_t __clock_id, int __flags,
 365                             const struct timespec *__req,
 366                             struct timespec *__rem);
 367
 368 /* Return clock ID for CPU-time clock.  */
 369 extern int clock_getcpuclockid (pid_t __pid, clockid_t *__clock_id) __THROW;
 370 #   endif /* __UCLIBC_HAS_THREADS_NATIVE__ */
 371 #  endif
 372
 373 #  if defined __UCLIBC_HAS_REALTIME__
 374 /* Create new per-process timer using CLOCK_ID.  */
 375 extern int timer_create (clockid_t __clock_id,
 376                          struct sigevent *__restrict __evp,
 377                          timer_t *__restrict __timerid) __THROW;
 378
 379 /* Delete timer TIMERID.  */
 380 extern int timer_delete (timer_t __timerid) __THROW;
 381
 382 /* Set timer TIMERID to VALUE, returning old value in OVLAUE.  */
 383 extern int timer_settime (timer_t __timerid, int __flags,
 384                           const struct itimerspec *__restrict __value,
 385                           struct itimerspec *__restrict __ovalue) __THROW;
 386
 387 /* Get current value of timer TIMERID and store it in VLAUE.  */
 388 extern int timer_gettime (timer_t __timerid, struct itimerspec *__value)
 389      __THROW;
 390
 391 /* Get expiration overrun for timer TIMERID.  */
 392 extern int timer_getoverrun (timer_t __timerid) __THROW;
 393 #  endif /* __UCLIBC_HAS_REALTIME__ */
 394 # endif /* __USE_POSIX199309 */
 395
 396 __END_DECLS
 397
 398 #endif /* <time.h> included.  */
 399
 400 #endif /* <time.h> not already included.  */