time/time.h

   1 /* Copyright (C) 1991-2003,2006,2009,2011,2012 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 __USE_ISOC11))                                 \
 113          || defined __need_timespec))
 114 # define __timespec_defined     1
 115
 116 # include <bits/types.h>        /* This defines __time_t for us.  */
 117
 118 /* POSIX.1b structure for a time value.  This is like a `struct timeval' but
 119    has nanoseconds instead of microseconds.  */
 120 struct timespec
 121   {
 122     __time_t tv_sec;            /* Seconds.  */
 123     long int tv_nsec;           /* Nanoseconds.  */
 124   };
 125
 126 #endif /* timespec not defined and <time.h> or need timespec.  */
 127 #undef  __need_timespec
 128
 129
 130 #ifdef  _TIME_H
 131 __BEGIN_NAMESPACE_STD
 132 /* Used by other time functions.  */
 133 struct tm
 134 {
 135   int tm_sec;                   /* Seconds.     [0-60] (1 leap second) */
 136   int tm_min;                   /* Minutes.     [0-59] */
 137   int tm_hour;                  /* Hours.       [0-23] */
 138   int tm_mday;                  /* Day.         [1-31] */
 139   int tm_mon;                   /* Month.       [0-11] */
 140   int tm_year;                  /* Year - 1900.  */
 141   int tm_wday;                  /* Day of week. [0-6] */
 142   int tm_yday;                  /* Days in year.[0-365] */
 143   int tm_isdst;                 /* DST.         [-1/0/1]*/
 144
 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 };
 153 __END_NAMESPACE_STD
 154 #if defined __USE_XOPEN || defined __USE_POSIX || defined __USE_MISC
 155 __USING_NAMESPACE_STD(tm)
 156 #endif
 157
 158
 159 # ifdef __USE_POSIX199309
 160 /* POSIX.1b structure for timer start values and intervals.  */
 161 struct itimerspec
 162   {
 163     struct timespec it_interval;
 164     struct timespec it_value;
 165   };
 166
 167 /* We can use a simple forward declaration.  */
 168 struct sigevent;
 169
 170 # endif /* POSIX.1b */
 171
 172 # ifdef __USE_XOPEN2K
 173 #  ifndef __pid_t_defined
 174 typedef __pid_t pid_t;
 175 #   define __pid_t_defined
 176 #  endif
 177 # endif
 178
 179
 180 # ifdef __USE_ISOC11
 181 /* Time base values for timespec_get.  */
 182 enum
 183   {
 184     TIME_UTC = 1
 185   };
 186 # endif
 187
 188
 189 __BEGIN_NAMESPACE_STD
 190 /* Time used by the program so far (user time + system time).
 191    The result / CLOCKS_PER_SECOND is program time in seconds.  */
 192 extern clock_t clock (void) __THROW;
 193
 194 /* Return the current time and put it in *TIMER if TIMER is not NULL.  */
 195 extern time_t time (time_t *__timer) __THROW;
 196
 197 /* Return the difference between TIME1 and TIME0.  */
 198 extern double difftime (time_t __time1, time_t __time0)
 199      __THROW __attribute__ ((__const__));
 200
 201 /* Return the `time_t' representation of TP and normalize TP.  */
 202 extern time_t mktime (struct tm *__tp) __THROW;
 203
 204
 205 /* Format TP into S according to FORMAT.
 206    Write no more than MAXSIZE characters and return the number
 207    of characters written, or 0 if it would exceed MAXSIZE.  */
 208 extern size_t strftime (char *__restrict __s, size_t __maxsize,
 209                         const char *__restrict __format,
 210                         const struct tm *__restrict __tp) __THROW;
 211 __END_NAMESPACE_STD
 212
 213 # ifdef __USE_XOPEN
 214 /* Parse S according to FORMAT and store binary time information in TP.
 215    The return value is a pointer to the first unparsed character in S.  */
 216 extern char *strptime (const char *__restrict __s,
 217                        const char *__restrict __fmt, struct tm *__tp)
 218      __THROW;
 219 # endif
 220
 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 # endif
 231
 232 # ifdef __USE_GNU
 233 extern char *strptime_l (const char *__restrict __s,
 234                          const char *__restrict __fmt, struct tm *__tp,
 235                          __locale_t __loc) __THROW;
 236 # endif
 237
 238
 239 __BEGIN_NAMESPACE_STD
 240 /* Return the `struct tm' representation of *TIMER
 241    in Universal Coordinated Time (aka Greenwich Mean Time).  */
 242 extern struct tm *gmtime (const time_t *__timer) __THROW;
 243
 244 /* Return the `struct tm' representation
 245    of *TIMER in the local timezone.  */
 246 extern struct tm *localtime (const time_t *__timer) __THROW;
 247 __END_NAMESPACE_STD
 248
 249 # if defined __USE_POSIX || defined __USE_MISC
 250 /* Return the `struct tm' representation of *TIMER in UTC,
 251    using *TP to store the result.  */
 252 extern struct tm *gmtime_r (const time_t *__restrict __timer,
 253                             struct tm *__restrict __tp) __THROW;
 254
 255 /* Return the `struct tm' representation of *TIMER in local time,
 256    using *TP to store the result.  */
 257 extern struct tm *localtime_r (const time_t *__restrict __timer,
 258                                struct tm *__restrict __tp) __THROW;
 259 # endif /* POSIX or misc */
 260
 261 __BEGIN_NAMESPACE_STD
 262 /* Return a string of the form "Day Mon dd hh:mm:ss yyyy\n"
 263    that is the representation of TP in this format.  */
 264 extern char *asctime (const struct tm *__tp) __THROW;
 265
 266 /* Equivalent to `asctime (localtime (timer))'.  */
 267 extern char *ctime (const time_t *__timer) __THROW;
 268 __END_NAMESPACE_STD
 269
 270 # if defined __USE_POSIX || defined __USE_MISC
 271 /* Reentrant versions of the above functions.  */
 272
 273 /* Return in BUF a string of the form "Day Mon dd hh:mm:ss yyyy\n"
 274    that is the representation of TP in this format.  */
 275 extern char *asctime_r (const struct tm *__restrict __tp,
 276                         char *__restrict __buf) __THROW;
 277
 278 /* Equivalent to `asctime_r (localtime_r (timer, *TMP*), buf)'.  */
 279 extern char *ctime_r (const time_t *__restrict __timer,
 280                       char *__restrict __buf) __THROW;
 281 # endif /* POSIX or misc */
 282
 283
 284 /* Defined in localtime.c.  */
 285 extern char *__tzname[2];       /* Current timezone names.  */
 286 extern int __daylight;          /* If daylight-saving time is ever in use.  */
 287 extern long int __timezone;     /* Seconds west of UTC.  */
 288
 289
 290 # ifdef __USE_POSIX
 291 /* Same as above.  */
 292 extern char *tzname[2];
 293
 294 /* Set time conversion information from the TZ environment variable.
 295    If TZ is not defined, a locale-dependent default is used.  */
 296 extern void tzset (void) __THROW;
 297 # endif
 298
 299 # if defined __USE_SVID || defined __USE_XOPEN
 300 extern int daylight;
 301 extern long int timezone;
 302 # endif
 303
 304 # ifdef __USE_SVID
 305 /* Set the system time to *WHEN.
 306    This call is restricted to the superuser.  */
 307 extern int stime (const time_t *__when) __THROW;
 308 # endif
 309
 310
 311 /* Nonzero if YEAR is a leap year (every 4 years,
 312    except every 100th isn't, and every 400th is).  */
 313 # define __isleap(year) \
 314   ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
 315
 316
 317 # ifdef __USE_MISC
 318 /* Miscellaneous functions many Unices inherited from the public domain
 319    localtime package.  These are included only for compatibility.  */
 320
 321 /* Like `mktime', but for TP represents Universal Time, not local time.  */
 322 extern time_t timegm (struct tm *__tp) __THROW;
 323
 324 /* Another name for `mktime'.  */
 325 extern time_t timelocal (struct tm *__tp) __THROW;
 326
 327 /* Return the number of days in YEAR.  */
 328 extern int dysize (int __year) __THROW  __attribute__ ((__const__));
 329 # endif
 330
 331
 332 # ifdef __USE_POSIX199309
 333 /* Pause execution for a number of nanoseconds.
 334
 335    This function is a cancellation point and therefore not marked with
 336    __THROW.  */
 337 extern int nanosleep (const struct timespec *__requested_time,
 338                       struct timespec *__remaining);
 339
 340
 341 /* Get resolution of clock CLOCK_ID.  */
 342 extern int clock_getres (clockid_t __clock_id, struct timespec *__res) __THROW;
 343
 344 /* Get current value of clock CLOCK_ID and store it in TP.  */
 345 extern int clock_gettime (clockid_t __clock_id, struct timespec *__tp) __THROW;
 346
 347 /* Set clock CLOCK_ID to value TP.  */
 348 extern int clock_settime (clockid_t __clock_id, const struct timespec *__tp)
 349      __THROW;
 350
 351 #  ifdef __USE_XOPEN2K
 352 /* High-resolution sleep with the specified clock.
 353
 354    This function is a cancellation point and therefore not marked with
 355    __THROW.  */
 356 extern int clock_nanosleep (clockid_t __clock_id, int __flags,
 357                             const struct timespec *__req,
 358                             struct timespec *__rem);
 359
 360 /* Return clock ID for CPU-time clock.  */
 361 extern int clock_getcpuclockid (pid_t __pid, clockid_t *__clock_id) __THROW;
 362 #  endif
 363
 364
 365 # ifdef __USE_ISOC11
 366 /* Set TS to calendar time based in time base BASE.  */
 367 extern int timespec_get (struct timespec *__ts, int __base)
 368      __THROW __nonnull ((1));
 369 # endif
 370
 371
 372 /* Create new per-process timer using CLOCK_ID.  */
 373 extern int timer_create (clockid_t __clock_id,
 374                          struct sigevent *__restrict __evp,
 375                          timer_t *__restrict __timerid) __THROW;
 376
 377 /* Delete timer TIMERID.  */
 378 extern int timer_delete (timer_t __timerid) __THROW;
 379
 380 /* Set timer TIMERID to VALUE, returning old value in OVLAUE.  */
 381 extern int timer_settime (timer_t __timerid, int __flags,
 382                           const struct itimerspec *__restrict __value,
 383                           struct itimerspec *__restrict __ovalue) __THROW;
 384
 385 /* Get current value of timer TIMERID and store it in VLAUE.  */
 386 extern int timer_gettime (timer_t __timerid, struct itimerspec *__value)
 387      __THROW;
 388
 389 /* Get expiration overrun for timer TIMERID.  */
 390 extern int timer_getoverrun (timer_t __timerid) __THROW;
 391 # endif
 392
 393
 394 # ifdef __USE_XOPEN_EXTENDED
 395 /* Set to one of the following values to indicate an error.
 396      1  the DATEMSK environment variable is null or undefined,
 397      2  the template file cannot be opened for reading,
 398      3  failed to get file status information,
 399      4  the template file is not a regular file,
 400      5  an error is encountered while reading the template file,
 401      6  memory allication failed (not enough memory available),
 402      7  there is no line in the template that matches the input,
 403      8  invalid input specification Example: February 31 or a time is
 404         specified that can not be represented in a time_t (representing
 405         the time in seconds since 00:00:00 UTC, January 1, 1970) */
 406 extern int getdate_err;
 407
 408 /* Parse the given string as a date specification and return a value
 409    representing the value.  The templates from the file identified by
 410    the environment variable DATEMSK are used.  In case of an error
 411    `getdate_err' is set.
 412
 413    This function is a possible cancellation point and therefore not
 414    marked with __THROW.  */
 415 extern struct tm *getdate (const char *__string);
 416 # endif
 417
 418 # ifdef __USE_GNU
 419 /* Since `getdate' is not reentrant because of the use of `getdate_err'
 420    and the static buffer to return the result in, we provide a thread-safe
 421    variant.  The functionality is the same.  The result is returned in
 422    the buffer pointed to by RESBUFP and in case of an error the return
 423    value is != 0 with the same values as given above for `getdate_err'.
 424
 425    This function is not part of POSIX and therefore no official
 426    cancellation point.  But due to similarity with an POSIX interface
 427    or due to the implementation it is a cancellation point and
 428    therefore not marked with __THROW.  */
 429 extern int getdate_r (const char *__restrict __string,
 430                       struct tm *__restrict __resbufp);
 431 # endif
 432
 433 __END_DECLS
 434
 435 #endif /* <time.h> included.  */
 436
 437 #endif /* <time.h> not already included.  */