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  *
  86  * Creates a new timer, and starts timing (i.e. g_timer_start() is
  87  * implicitly called for you).
  88  *
  89  * Returns: a new #GTimer.
  90  **/
  91 GTimer*
  92 g_timer_new (void)
  93 {
  94   GTimer *timer;
  95
  96   timer = g_new (GTimer, 1);
  97   timer->active = TRUE;
  98
  99   timer->start = g_get_monotonic_time ();
 100
 101   return timer;
 102 }
 103
 104 /**
 105  * g_timer_destroy:
 106  * @timer: a #GTimer to destroy.
 107  *
 108  * Destroys a timer, freeing associated resources.
 109  **/
 110 void
 111 g_timer_destroy (GTimer *timer)
 112 {
 113   g_return_if_fail (timer != NULL);
 114
 115   g_free (timer);
 116 }
 117
 118 /**
 119  * g_timer_start:
 120  * @timer: a #GTimer.
 121  *
 122  * Marks a start time, so that future calls to g_timer_elapsed() will
 123  * report the time since g_timer_start() was called. g_timer_new()
 124  * automatically marks the start time, so no need to call
 125  * g_timer_start() immediately after creating the timer.
 126  **/
 127 void
 128 g_timer_start (GTimer *timer)
 129 {
 130   g_return_if_fail (timer != NULL);
 131
 132   timer->active = TRUE;
 133
 134   timer->start = g_get_monotonic_time ();
 135 }
 136
 137 /**
 138  * g_timer_stop:
 139  * @timer: a #GTimer.
 140  *
 141  * Marks an end time, so calls to g_timer_elapsed() will return the
 142  * difference between this end time and the start time.
 143  **/
 144 void
 145 g_timer_stop (GTimer *timer)
 146 {
 147   g_return_if_fail (timer != NULL);
 148
 149   timer->active = FALSE;
 150
 151   timer->end = g_get_monotonic_time ();
 152 }
 153
 154 /**
 155  * g_timer_reset:
 156  * @timer: a #GTimer.
 157  *
 158  * This function is useless; it's fine to call g_timer_start() on an
 159  * already-started timer to reset the start time, so g_timer_reset()
 160  * serves no purpose.
 161  **/
 162 void
 163 g_timer_reset (GTimer *timer)
 164 {
 165   g_return_if_fail (timer != NULL);
 166
 167   timer->start = g_get_monotonic_time ();
 168 }
 169
 170 /**
 171  * g_timer_continue:
 172  * @timer: a #GTimer.
 173  *
 174  * Resumes a timer that has previously been stopped with
 175  * g_timer_stop(). g_timer_stop() must be called before using this
 176  * function.
 177  *
 178  * Since: 2.4
 179  **/
 180 void
 181 g_timer_continue (GTimer *timer)
 182 {
 183   guint64 elapsed;
 184
 185   g_return_if_fail (timer != NULL);
 186   g_return_if_fail (timer->active == FALSE);
 187
 188   /* Get elapsed time and reset timer start time
 189    *  to the current time minus the previously
 190    *  elapsed interval.
 191    */
 192
 193   elapsed = timer->end - timer->start;
 194
 195   timer->start = g_get_monotonic_time ();
 196
 197   timer->start -= elapsed;
 198
 199   timer->active = TRUE;
 200 }
 201
 202 /**
 203  * g_timer_elapsed:
 204  * @timer: a #GTimer.
 205  * @microseconds: return location for the fractional part of seconds
 206  *                elapsed, in microseconds (that is, the total number
 207  *                of microseconds elapsed, modulo 1000000), or %NULL
 208  *
 209  * If @timer has been started but not stopped, obtains the time since
 210  * the timer was started. If @timer has been stopped, obtains the
 211  * elapsed time between the time it was started and the time it was
 212  * stopped. The return value is the number of seconds elapsed,
 213  * including any fractional part. The @microseconds out parameter is
 214  * essentially useless.
 215  *
 216  * Returns: seconds elapsed as a floating point value, including any
 217  *          fractional part.
 218  **/
 219 gdouble
 220 g_timer_elapsed (GTimer *timer,
 221                  gulong *microseconds)
 222 {
 223   gdouble total;
 224   gint64 elapsed;
 225
 226   g_return_val_if_fail (timer != NULL, 0);
 227
 228   if (timer->active)
 229     timer->end = g_get_monotonic_time ();
 230
 231   elapsed = timer->end - timer->start;
 232
 233   total = elapsed / 1e6;
 234
 235   if (microseconds)
 236     *microseconds = elapsed % 1000000;
 237
 238   return total;
 239 }
 240
 241 /**
 242  * g_usleep:
 243  * @microseconds: number of microseconds to pause
 244  *
 245  * Pauses the current thread for the given number of microseconds.
 246  *
 247  * There are 1 million microseconds per second (represented by the
 248  * #G_USEC_PER_SEC macro). g_usleep() may have limited precision,
 249  * depending on hardware and operating system; don't rely on the exact
 250  * length of the sleep.
 251  */
 252 void
 253 g_usleep (gulong microseconds)
 254 {
 255 #ifdef G_OS_WIN32
 256   Sleep (microseconds / 1000);
 257 #else
 258   struct timespec request, remaining;
 259   request.tv_sec = microseconds / G_USEC_PER_SEC;
 260   request.tv_nsec = 1000 * (microseconds % G_USEC_PER_SEC);
 261   while (nanosleep (&request, &remaining) == -1 && errno == EINTR)
 262     request = remaining;
 263 #endif
 264 }
 265
 266 /**
 267  * g_time_val_add:
 268  * @time_: a #GTimeVal
 269  * @microseconds: number of microseconds to add to @time
 270  *
 271  * Adds the given number of microseconds to @time_. @microseconds can
 272  * also be negative to decrease the value of @time_.
 273  **/
 274 void
 275 g_time_val_add (GTimeVal *time_, glong microseconds)
 276 {
 277   g_return_if_fail (time_->tv_usec >= 0 && time_->tv_usec < G_USEC_PER_SEC);
 278
 279   if (microseconds >= 0)
 280     {
 281       time_->tv_usec += microseconds % G_USEC_PER_SEC;
 282       time_->tv_sec += microseconds / G_USEC_PER_SEC;
 283       if (time_->tv_usec >= G_USEC_PER_SEC)
 284        {
 285          time_->tv_usec -= G_USEC_PER_SEC;
 286          time_->tv_sec++;
 287        }
 288     }
 289   else
 290     {
 291       microseconds *= -1;
 292       time_->tv_usec -= microseconds % G_USEC_PER_SEC;
 293       time_->tv_sec -= microseconds / G_USEC_PER_SEC;
 294       if (time_->tv_usec < 0)
 295        {
 296          time_->tv_usec += G_USEC_PER_SEC;
 297          time_->tv_sec--;
 298        }
 299     }
 300 }
 301
 302 /* converts a broken down date representation, relative to UTC, to
 303  * a timestamp; it uses timegm() if it's available.
 304  */
 305 static time_t
 306 mktime_utc (struct tm *tm)
 307 {
 308   time_t retval;
 309
 310 #ifndef HAVE_TIMEGM
 311   static const gint days_before[] =
 312   {
 313     0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
 314   };
 315 #endif
 316
 317 #ifndef HAVE_TIMEGM
 318   if (tm->tm_mon < 0 || tm->tm_mon > 11)
 319     return (time_t) -1;
 320
 321   retval = (tm->tm_year - 70) * 365;
 322   retval += (tm->tm_year - 68) / 4;
 323   retval += days_before[tm->tm_mon] + tm->tm_mday - 1;
 324
 325   if (tm->tm_year % 4 == 0 && tm->tm_mon < 2)
 326     retval -= 1;
 327
 328   retval = ((((retval * 24) + tm->tm_hour) * 60) + tm->tm_min) * 60 + tm->tm_sec;
 329 #else
 330   retval = timegm (tm);
 331 #endif /* !HAVE_TIMEGM */
 332
 333   return retval;
 334 }
 335
 336 /**
 337  * g_time_val_from_iso8601:
 338  * @iso_date: an ISO 8601 encoded date string
 339  * @time_: (out): a #GTimeVal
 340  *
 341  * Converts a string containing an ISO 8601 encoded date and time
 342  * to a #GTimeVal and puts it into @time_.
 343  *
 344  * @iso_date must include year, month, day, hours, minutes, and
 345  * seconds. It can optionally include fractions of a second and a time
 346  * zone indicator. (In the absence of any time zone indication, the
 347  * timestamp is assumed to be in local time.)
 348  *
 349  * Return value: %TRUE if the conversion was successful.
 350  *
 351  * Since: 2.12
 352  */
 353 gboolean
 354 g_time_val_from_iso8601 (const gchar *iso_date,
 355                          GTimeVal    *time_)
 356 {
 357   struct tm tm = {0};
 358   long val;
 359
 360   g_return_val_if_fail (iso_date != NULL, FALSE);
 361   g_return_val_if_fail (time_ != NULL, FALSE);
 362
 363   /* Ensure that the first character is a digit,
 364    * the first digit of the date, otherwise we don't
 365    * have an ISO 8601 date */
 366   while (g_ascii_isspace (*iso_date))
 367     iso_date++;
 368
 369   if (*iso_date == '\0')
 370     return FALSE;
 371
 372   if (!g_ascii_isdigit (*iso_date) && *iso_date != '-' && *iso_date != '+')
 373     return FALSE;
 374
 375   val = strtoul (iso_date, (char **)&iso_date, 10);
 376   if (*iso_date == '-')
 377     {
 378       /* YYYY-MM-DD */
 379       tm.tm_year = val - 1900;
 380       iso_date++;
 381       tm.tm_mon = strtoul (iso_date, (char **)&iso_date, 10) - 1;
 382
 383       if (*iso_date++ != '-')
 384         return FALSE;
 385
 386       tm.tm_mday = strtoul (iso_date, (char **)&iso_date, 10);
 387     }
 388   else
 389     {
 390       /* YYYYMMDD */
 391       tm.tm_mday = val % 100;
 392       tm.tm_mon = (val % 10000) / 100 - 1;
 393       tm.tm_year = val / 10000 - 1900;
 394     }
 395
 396   if (*iso_date != 'T')
 397     {
 398       /* Date only */
 399       if (*iso_date == '\0')
 400         return TRUE;
 401       return FALSE;
 402     }
 403
 404   iso_date++;
 405
 406   /* If there is a 'T' then there has to be a time */
 407   if (!g_ascii_isdigit (*iso_date))
 408     return FALSE;
 409
 410   val = strtoul (iso_date, (char **)&iso_date, 10);
 411   if (*iso_date == ':')
 412     {
 413       /* hh:mm:ss */
 414       tm.tm_hour = val;
 415       iso_date++;
 416       tm.tm_min = strtoul (iso_date, (char **)&iso_date, 10);
 417
 418       if (*iso_date++ != ':')
 419         return FALSE;
 420
 421       tm.tm_sec = strtoul (iso_date, (char **)&iso_date, 10);
 422     }
 423   else
 424     {
 425       /* hhmmss */
 426       tm.tm_sec = val % 100;
 427       tm.tm_min = (val % 10000) / 100;
 428       tm.tm_hour = val / 10000;
 429     }
 430
 431   time_->tv_usec = 0;
 432
 433   if (*iso_date == ',' || *iso_date == '.')
 434     {
 435       glong mul = 100000;
 436
 437       while (g_ascii_isdigit (*++iso_date))
 438         {
 439           time_->tv_usec += (*iso_date - '0') * mul;
 440           mul /= 10;
 441         }
 442     }
 443
 444   /* Now parse the offset and convert tm to a time_t */
 445   if (*iso_date == 'Z')
 446     {
 447       iso_date++;
 448       time_->tv_sec = mktime_utc (&tm);
 449     }
 450   else if (*iso_date == '+' || *iso_date == '-')
 451     {
 452       gint sign = (*iso_date == '+') ? -1 : 1;
 453
 454       val = strtoul (iso_date + 1, (char **)&iso_date, 10);
 455
 456       if (*iso_date == ':')
 457         val = 60 * val + strtoul (iso_date + 1, (char **)&iso_date, 10);
 458       else
 459         val = 60 * (val / 100) + (val % 100);
 460
 461       time_->tv_sec = mktime_utc (&tm) + (time_t) (60 * val * sign);
 462     }
 463   else
 464     {
 465       /* No "Z" or offset, so local time */
 466       tm.tm_isdst = -1; /* locale selects DST */
 467       time_->tv_sec = mktime (&tm);
 468     }
 469
 470   while (g_ascii_isspace (*iso_date))
 471     iso_date++;
 472
 473   return *iso_date == '\0';
 474 }
 475
 476 /**
 477  * g_time_val_to_iso8601:
 478  * @time_: a #GTimeVal
 479  *
 480  * Converts @time_ into an RFC 3339 encoded string, relative to the
 481  * Coordinated Universal Time (UTC). This is one of the many formats
 482  * allowed by ISO 8601.
 483  *
 484  * ISO 8601 allows a large number of date/time formats, with or without
 485  * punctuation and optional elements. The format returned by this function
 486  * is a complete date and time, with optional punctuation included, the
 487  * UTC time zone represented as "Z", and the @tv_usec part included if
 488  * and only if it is nonzero, i.e. either
 489  * "YYYY-MM-DDTHH:MM:SSZ" or "YYYY-MM-DDTHH:MM:SS.fffffZ".
 490  *
 491  * This corresponds to the Internet date/time format defined by
 492  * <ulink url="https://www.ietf.org/rfc/rfc3339.txt">RFC 3339</ulink>, and
 493  * to either of the two most-precise formats defined by
 494  * <ulink url="http://www.w3.org/TR/NOTE-datetime-19980827">the W3C Note
 495  * "Date and Time Formats"</ulink>. Both of these documents are profiles of
 496  * ISO 8601.
 497  *
 498  * Use g_date_time_format() or g_strdup_printf() if a different
 499  * variation of ISO 8601 format is required.
 500  *
 501  * Return value: a newly allocated string containing an ISO 8601 date
 502  *
 503  * Since: 2.12
 504  */
 505 gchar *
 506 g_time_val_to_iso8601 (GTimeVal *time_)
 507 {
 508   gchar *retval;
 509   struct tm *tm;
 510 #ifdef HAVE_GMTIME_R
 511   struct tm tm_;
 512 #endif
 513   time_t secs;
 514
 515   g_return_val_if_fail (time_->tv_usec >= 0 && time_->tv_usec < G_USEC_PER_SEC, NULL);
 516
 517  secs = time_->tv_sec;
 518 #ifdef _WIN32
 519  tm = gmtime (&secs);
 520 #else
 521 #ifdef HAVE_GMTIME_R
 522   tm = gmtime_r (&secs, &tm_);
 523 #else
 524   tm = gmtime (&secs);
 525 #endif
 526 #endif
 527
 528   if (time_->tv_usec != 0)
 529     {
 530       /* ISO 8601 date and time format, with fractionary seconds:
 531        *   YYYY-MM-DDTHH:MM:SS.MMMMMMZ
 532        */
 533       retval = g_strdup_printf ("%4d-%02d-%02dT%02d:%02d:%02d.%06ldZ",
 534                                 tm->tm_year + 1900,
 535                                 tm->tm_mon + 1,
 536                                 tm->tm_mday,
 537                                 tm->tm_hour,
 538                                 tm->tm_min,
 539                                 tm->tm_sec,
 540                                 time_->tv_usec);
 541     }
 542   else
 543     {
 544       /* ISO 8601 date and time format:
 545        *   YYYY-MM-DDTHH:MM:SSZ
 546        */
 547       retval = g_strdup_printf ("%4d-%02d-%02dT%02d:%02d:%02dZ",
 548                                 tm->tm_year + 1900,
 549                                 tm->tm_mon + 1,
 550                                 tm->tm_mday,
 551                                 tm->tm_hour,
 552                                 tm->tm_min,
 553                                 tm->tm_sec);
 554     }
 555
 556   return retval;
 557 }