glib/gtimer.c

   1 /* GLIB - Library of useful routines for C programming
   2  * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This 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 of the License, or (at your option) any later version.
   8  *
   9  * This 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 this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  22  * file for a list of people on the GLib Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 /*
  28  * MT safe
  29  */
  30
  31 #include "config.h"
  32 #include "glibconfig.h"
  33
  34 #include <stdlib.h>
  35
  36 #ifdef HAVE_UNISTD_H
  37 #include <unistd.h>
  38 #endif /* HAVE_UNISTD_H */
  39
  40 #ifdef HAVE_SYS_TIME_H
  41 #include <sys/time.h>
  42 #endif
  43 #include <time.h>
  44 #ifndef G_OS_WIN32
  45 #include <errno.h>
  46 #endif /* G_OS_WIN32 */
  47
  48 #ifdef G_OS_WIN32
  49 #include <windows.h>
  50 #endif /* G_OS_WIN32 */
  51
  52 #include "gtimer.h"
  53
  54 #include "gmem.h"
  55 #include "gstrfuncs.h"
  56 #include "gtestutils.h"
  57 #include "gmain.h"
  58
  59 /**
  60  * SECTION:timers
  61  * @title: Timers
  62  * @short_description: keep track of elapsed time
  63  *
  64  * #GTimer records a start time, and counts microseconds elapsed since
  65  * that time. This is done somewhat differently on different platforms,
  66  * and can be tricky to get exactly right, so #GTimer provides a
  67  * portable/convenient interface.
  68  **/
  69
  70 /**
  71  * GTimer:
  72  *
  73  * Opaque datatype that records a start time.
  74  **/
  75 struct _GTimer
  76 {
  77   guint64 start;
  78   guint64 end;
  79
  80   guint active : 1;
  81 };
  82
  83 /**
  84  * g_timer_new:
  85  * @Returns: a new #GTimer.
  86  *
  87  * Creates a new timer, and starts timing (i.e. g_timer_start() is
  88  * implicitly called for you).
  89  **/
  90 GTimer*
  91 g_timer_new (void)
  92 {
  93   GTimer *timer;
  94
  95   timer = g_new (GTimer, 1);
  96   timer->active = TRUE;
  97
  98   timer->start = g_get_monotonic_time ();
  99
 100   return timer;
 101 }
 102
 103 /**
 104  * g_timer_destroy:
 105  * @timer: a #GTimer to destroy.
 106  *
 107  * Destroys a timer, freeing associated resources.
 108  **/
 109 void
 110 g_timer_destroy (GTimer *timer)
 111 {
 112   g_return_if_fail (timer != NULL);
 113
 114   g_free (timer);
 115 }
 116
 117 /**
 118  * g_timer_start:
 119  * @timer: a #GTimer.
 120  *
 121  * Marks a start time, so that future calls to g_timer_elapsed() will
 122  * report the time since g_timer_start() was called. g_timer_new()
 123  * automatically marks the start time, so no need to call
 124  * g_timer_start() immediately after creating the timer.
 125  **/
 126 void
 127 g_timer_start (GTimer *timer)
 128 {
 129   g_return_if_fail (timer != NULL);
 130
 131   timer->active = TRUE;
 132
 133   timer->start = g_get_monotonic_time ();
 134 }
 135
 136 /**
 137  * g_timer_stop:
 138  * @timer: a #GTimer.
 139  *
 140  * Marks an end time, so calls to g_timer_elapsed() will return the
 141  * difference between this end time and the start time.
 142  **/
 143 void
 144 g_timer_stop (GTimer *timer)
 145 {
 146   g_return_if_fail (timer != NULL);
 147
 148   timer->active = FALSE;
 149
 150   timer->end = g_get_monotonic_time ();
 151 }
 152
 153 /**
 154  * g_timer_reset:
 155  * @timer: a #GTimer.
 156  *
 157  * This function is useless; it's fine to call g_timer_start() on an
 158  * already-started timer to reset the start time, so g_timer_reset()
 159  * serves no purpose.
 160  **/
 161 void
 162 g_timer_reset (GTimer *timer)
 163 {
 164   g_return_if_fail (timer != NULL);
 165
 166   timer->start = g_get_monotonic_time ();
 167 }
 168
 169 /**
 170  * g_timer_continue:
 171  * @timer: a #GTimer.
 172  *
 173  * Resumes a timer that has previously been stopped with
 174  * g_timer_stop(). g_timer_stop() must be called before using this
 175  * function.
 176  *
 177  * Since: 2.4
 178  **/
 179 void
 180 g_timer_continue (GTimer *timer)
 181 {
 182   guint64 elapsed;
 183
 184   g_return_if_fail (timer != NULL);
 185   g_return_if_fail (timer->active == FALSE);
 186
 187   /* Get elapsed time and reset timer start time
 188    *  to the current time minus the previously
 189    *  elapsed interval.
 190    */
 191
 192   elapsed = timer->end - timer->start;
 193
 194   timer->start = g_get_monotonic_time ();
 195
 196   timer->start -= elapsed;
 197
 198   timer->active = TRUE;
 199 }
 200
 201 /**
 202  * g_timer_elapsed:
 203  * @timer: a #GTimer.
 204  * @microseconds: return location for the fractional part of seconds
 205  *                elapsed, in microseconds (that is, the total number
 206  *                of microseconds elapsed, modulo 1000000), or %NULL
 207  * @Returns: seconds elapsed as a floating point value, including any
 208  *           fractional part.
 209  *
 210  * If @timer has been started but not stopped, obtains the time since
 211  * the timer was started. If @timer has been stopped, obtains the
 212  * elapsed time between the time it was started and the time it was
 213  * stopped. The return value is the number of seconds elapsed,
 214  * including any fractional part. The @microseconds out parameter is
 215  * essentially useless.
 216  **/
 217 gdouble
 218 g_timer_elapsed (GTimer *timer,
 219                  gulong *microseconds)
 220 {
 221   gdouble total;
 222   gint64 elapsed;
 223
 224   g_return_val_if_fail (timer != NULL, 0);
 225
 226   if (timer->active)
 227     timer->end = g_get_monotonic_time ();
 228
 229   elapsed = timer->end - timer->start;
 230
 231   total = elapsed / 1e6;
 232
 233   if (microseconds)
 234     *microseconds = elapsed % 1000000;
 235
 236   return total;
 237 }
 238
 239 /**
 240  * g_usleep:
 241  * @microseconds: number of microseconds to pause
 242  *
 243  * Pauses the current thread for the given number of microseconds.
 244  *
 245  * There are 1 million microseconds per second (represented by the
 246  * #G_USEC_PER_SEC macro). g_usleep() may have limited precision,
 247  * depending on hardware and operating system; don't rely on the exact
 248  * length of the sleep.
 249  */
 250 void
 251 g_usleep (gulong microseconds)
 252 {
 253 #ifdef G_OS_WIN32
 254   Sleep (microseconds / 1000);
 255 #else
 256   struct timespec request, remaining;
 257   request.tv_sec = microseconds / G_USEC_PER_SEC;
 258   request.tv_nsec = 1000 * (microseconds % G_USEC_PER_SEC);
 259   while (nanosleep (&request, &remaining) == -1 && errno == EINTR)
 260     request = remaining;
 261 #endif
 262 }
 263
 264 /**
 265  * g_time_val_add:
 266  * @time_: a #GTimeVal
 267  * @microseconds: number of microseconds to add to @time
 268  *
 269  * Adds the given number of microseconds to @time_. @microseconds can
 270  * also be negative to decrease the value of @time_.
 271  **/
 272 void
 273 g_time_val_add (GTimeVal *time_, glong microseconds)
 274 {
 275   g_return_if_fail (time_->tv_usec >= 0 && time_->tv_usec < G_USEC_PER_SEC);
 276
 277   if (microseconds >= 0)
 278     {
 279       time_->tv_usec += microseconds % G_USEC_PER_SEC;
 280       time_->tv_sec += microseconds / G_USEC_PER_SEC;
 281       if (time_->tv_usec >= G_USEC_PER_SEC)
 282        {
 283          time_->tv_usec -= G_USEC_PER_SEC;
 284          time_->tv_sec++;
 285        }
 286     }
 287   else
 288     {
 289       microseconds *= -1;
 290       time_->tv_usec -= microseconds % G_USEC_PER_SEC;
 291       time_->tv_sec -= microseconds / G_USEC_PER_SEC;
 292       if (time_->tv_usec < 0)
 293        {
 294          time_->tv_usec += G_USEC_PER_SEC;
 295          time_->tv_sec--;
 296        }
 297     }
 298 }
 299
 300 /* converts a broken down date representation, relative to UTC, to
 301  * a timestamp; it uses timegm() if it's available.
 302  */
 303 static time_t
 304 mktime_utc (struct tm *tm)
 305 {
 306   time_t retval;
 307
 308 #ifndef HAVE_TIMEGM
 309   static const gint days_before[] =
 310   {
 311     0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
 312   };
 313 #endif
 314
 315 #ifndef HAVE_TIMEGM
 316   if (tm->tm_mon < 0 || tm->tm_mon > 11)
 317     return (time_t) -1;
 318
 319   retval = (tm->tm_year - 70) * 365;
 320   retval += (tm->tm_year - 68) / 4;
 321   retval += days_before[tm->tm_mon] + tm->tm_mday - 1;
 322
 323   if (tm->tm_year % 4 == 0 && tm->tm_mon < 2)
 324     retval -= 1;
 325
 326   retval = ((((retval * 24) + tm->tm_hour) * 60) + tm->tm_min) * 60 + tm->tm_sec;
 327 #else
 328   retval = timegm (tm);
 329 #endif /* !HAVE_TIMEGM */
 330
 331   return retval;
 332 }
 333
 334 /**
 335  * g_time_val_from_iso8601:
 336  * @iso_date: an ISO 8601 encoded date string
 337  * @time_: (out): a #GTimeVal
 338  *
 339  * Converts a string containing an ISO 8601 encoded date and time
 340  * to a #GTimeVal and puts it into @time_.
 341  *
 342  * @iso_date must include year, month, day, hours, minutes, and
 343  * seconds. It can optionally include fractions of a second and a time
 344  * zone indicator. (In the absence of any time zone indication, the
 345  * timestamp is assumed to be in local time.)
 346  *
 347  * Return value: %TRUE if the conversion was successful.
 348  *
 349  * Since: 2.12
 350  */
 351 gboolean
 352 g_time_val_from_iso8601 (const gchar *iso_date,
 353                          GTimeVal    *time_)
 354 {
 355   struct tm tm = {0};
 356   long val;
 357
 358   g_return_val_if_fail (iso_date != NULL, FALSE);
 359   g_return_val_if_fail (time_ != NULL, FALSE);
 360
 361   /* Ensure that the first character is a digit,
 362    * the first digit of the date, otherwise we don't
 363    * have an ISO 8601 date */
 364   while (g_ascii_isspace (*iso_date))
 365     iso_date++;
 366
 367   if (*iso_date == '\0')
 368     return FALSE;
 369
 370   if (!g_ascii_isdigit (*iso_date) && *iso_date != '-' && *iso_date != '+')
 371     return FALSE;
 372
 373   val = strtoul (iso_date, (char **)&iso_date, 10);
 374   if (*iso_date == '-')
 375     {
 376       /* YYYY-MM-DD */
 377       tm.tm_year = val - 1900;
 378       iso_date++;
 379       tm.tm_mon = strtoul (iso_date, (char **)&iso_date, 10) - 1;
 380
 381       if (*iso_date++ != '-')
 382         return FALSE;
 383
 384       tm.tm_mday = strtoul (iso_date, (char **)&iso_date, 10);
 385     }
 386   else
 387     {
 388       /* YYYYMMDD */
 389       tm.tm_mday = val % 100;
 390       tm.tm_mon = (val % 10000) / 100 - 1;
 391       tm.tm_year = val / 10000 - 1900;
 392     }
 393
 394   if (*iso_date != 'T')
 395     {
 396       /* Date only */
 397       if (*iso_date == '\0')
 398         return TRUE;
 399       return FALSE;
 400     }
 401
 402   iso_date++;
 403
 404   /* If there is a 'T' then there has to be a time */
 405   if (!g_ascii_isdigit (*iso_date))
 406     return FALSE;
 407
 408   val = strtoul (iso_date, (char **)&iso_date, 10);
 409   if (*iso_date == ':')
 410     {
 411       /* hh:mm:ss */
 412       tm.tm_hour = val;
 413       iso_date++;
 414       tm.tm_min = strtoul (iso_date, (char **)&iso_date, 10);
 415
 416       if (*iso_date++ != ':')
 417         return FALSE;
 418
 419       tm.tm_sec = strtoul (iso_date, (char **)&iso_date, 10);
 420     }
 421   else
 422     {
 423       /* hhmmss */
 424       tm.tm_sec = val % 100;
 425       tm.tm_min = (val % 10000) / 100;
 426       tm.tm_hour = val / 10000;
 427     }
 428
 429   time_->tv_usec = 0;
 430
 431   if (*iso_date == ',' || *iso_date == '.')
 432     {
 433       glong mul = 100000;
 434
 435       while (g_ascii_isdigit (*++iso_date))
 436         {
 437           time_->tv_usec += (*iso_date - '0') * mul;
 438           mul /= 10;
 439         }
 440     }
 441
 442   /* Now parse the offset and convert tm to a time_t */
 443   if (*iso_date == 'Z')
 444     {
 445       iso_date++;
 446       time_->tv_sec = mktime_utc (&tm);
 447     }
 448   else if (*iso_date == '+' || *iso_date == '-')
 449     {
 450       gint sign = (*iso_date == '+') ? -1 : 1;
 451
 452       val = strtoul (iso_date + 1, (char **)&iso_date, 10);
 453
 454       if (*iso_date == ':')
 455         val = 60 * val + strtoul (iso_date + 1, (char **)&iso_date, 10);
 456       else
 457         val = 60 * (val / 100) + (val % 100);
 458
 459       time_->tv_sec = mktime_utc (&tm) + (time_t) (60 * val * sign);
 460     }
 461   else
 462     {
 463       /* No "Z" or offset, so local time */
 464       tm.tm_isdst = -1; /* locale selects DST */
 465       time_->tv_sec = mktime (&tm);
 466     }
 467
 468   while (g_ascii_isspace (*iso_date))
 469     iso_date++;
 470
 471   return *iso_date == '\0';
 472 }
 473
 474 /**
 475  * g_time_val_to_iso8601:
 476  * @time_: a #GTimeVal
 477  *
 478  * Converts @time_ into an RFC 3339 encoded string, relative to the
 479  * Coordinated Universal Time (UTC). This is one of the many formats
 480  * allowed by ISO 8601.
 481  *
 482  * ISO 8601 allows a large number of date/time formats, with or without
 483  * punctuation and optional elements. The format returned by this function
 484  * is a complete date and time, with optional punctuation included, the
 485  * UTC time zone represented as "Z", and the @tv_usec part included if
 486  * and only if it is nonzero, i.e. either
 487  * "YYYY-MM-DDTHH:MM:SSZ" or "YYYY-MM-DDTHH:MM:SS.fffffZ".
 488  *
 489  * This corresponds to the Internet date/time format defined by
 490  * <ulink url="https://www.ietf.org/rfc/rfc3339.txt">RFC 3339</ulink>, and
 491  * to either of the two most-precise formats defined by
 492  * <ulink url="http://www.w3.org/TR/NOTE-datetime-19980827">the W3C Note
 493  * "Date and Time Formats"</ulink>. Both of these documents are profiles of
 494  * ISO 8601.
 495  *
 496  * Use g_date_time_format() or g_strdup_printf() if a different
 497  * variation of ISO 8601 format is required.
 498  *
 499  * Return value: a newly allocated string containing an ISO 8601 date
 500  *
 501  * Since: 2.12
 502  */
 503 gchar *
 504 g_time_val_to_iso8601 (GTimeVal *time_)
 505 {
 506   gchar *retval;
 507   struct tm *tm;
 508 #ifdef HAVE_GMTIME_R
 509   struct tm tm_;
 510 #endif
 511   time_t secs;
 512
 513   g_return_val_if_fail (time_->tv_usec >= 0 && time_->tv_usec < G_USEC_PER_SEC, NULL);
 514
 515  secs = time_->tv_sec;
 516 #ifdef _WIN32
 517  tm = gmtime (&secs);
 518 #else
 519 #ifdef HAVE_GMTIME_R
 520   tm = gmtime_r (&secs, &tm_);
 521 #else
 522   tm = gmtime (&secs);
 523 #endif
 524 #endif
 525
 526   if (time_->tv_usec != 0)
 527     {
 528       /* ISO 8601 date and time format, with fractionary seconds:
 529        *   YYYY-MM-DDTHH:MM:SS.MMMMMMZ
 530        */
 531       retval = g_strdup_printf ("%4d-%02d-%02dT%02d:%02d:%02d.%06ldZ",
 532                                 tm->tm_year + 1900,
 533                                 tm->tm_mon + 1,
 534                                 tm->tm_mday,
 535                                 tm->tm_hour,
 536                                 tm->tm_min,
 537                                 tm->tm_sec,
 538                                 time_->tv_usec);
 539     }
 540   else
 541     {
 542       /* ISO 8601 date and time format:
 543        *   YYYY-MM-DDTHH:MM:SSZ
 544        */
 545       retval = g_strdup_printf ("%4d-%02d-%02dT%02d:%02d:%02dZ",
 546                                 tm->tm_year + 1900,
 547                                 tm->tm_mon + 1,
 548                                 tm->tm_mday,
 549                                 tm->tm_hour,
 550                                 tm->tm_min,
 551                                 tm->tm_sec);
 552     }
 553
 554   return retval;
 555 }