glib/glib/gdatetime.c
Dan Winship 158dde0507 Replace #ifdef HAVE_UNISTD_H checks with #ifdef G_OS_UNIX
In Windows development environments that have it, <unistd.h> is mostly
just a wrapper around several other native headers (in particular,
<io.h>, which contains read(), close(), etc, and <process.h>, which
contains getpid()). But given that some Windows dev environments don't
have <unistd.h>, everything that uses those functions on Windows
already needed to include the correct Windows header as well, and so
there is never any point to including <unistd.h> on Windows.

Also, remove some <unistd.h> includes (and a few others) that were
unnecessary even on unix.

https://bugzilla.gnome.org/show_bug.cgi?id=710519
2013-11-20 09:25:39 -05:00

2837 lines
76 KiB
C

/* gdatetime.c
*
* Copyright (C) 2009-2010 Christian Hergert <chris@dronelabs.com>
* Copyright (C) 2010 Thiago Santos <thiago.sousa.santos@collabora.co.uk>
* Copyright (C) 2010 Emmanuele Bassi <ebassi@linux.intel.com>
* Copyright © 2010 Codethink Limited
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of the
* licence, or (at your option) any later version.
*
* This is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
* USA.
*
* Authors: Christian Hergert <chris@dronelabs.com>
* Thiago Santos <thiago.sousa.santos@collabora.co.uk>
* Emmanuele Bassi <ebassi@linux.intel.com>
* Ryan Lortie <desrt@desrt.ca>
*/
/* Algorithms within this file are based on the Calendar FAQ by
* Claus Tondering. It can be found at
* http://www.tondering.dk/claus/cal/calendar29.txt
*
* Copyright and disclaimer
* ------------------------
* This document is Copyright (C) 2008 by Claus Tondering.
* E-mail: claus@tondering.dk. (Please include the word
* "calendar" in the subject line.)
* The document may be freely distributed, provided this
* copyright notice is included and no money is charged for
* the document.
*
* This document is provided "as is". No warranties are made as
* to its correctness.
*/
/* Prologue {{{1 */
#include "config.h"
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_LANGINFO_TIME
#include <langinfo.h>
#endif
#include "gdatetime.h"
#include "gslice.h"
#include "gatomic.h"
#include "gcharset.h"
#include "gconvert.h"
#include "gfileutils.h"
#include "ghash.h"
#include "gmain.h"
#include "gmappedfile.h"
#include "gstrfuncs.h"
#include "gtestutils.h"
#include "gthread.h"
#include "gtimezone.h"
#include "glibintl.h"
#ifndef G_OS_WIN32
#include <sys/time.h>
#include <time.h>
#endif /* !G_OS_WIN32 */
/**
* SECTION:date-time
* @title: GDateTime
* @short_description: a structure representing Date and Time
* @see_also: #GTimeZone
*
* #GDateTime is a structure that combines a Gregorian date and time
* into a single structure. It provides many conversion and methods to
* manipulate dates and times. Time precision is provided down to
* microseconds and the time can range (proleptically) from 0001-01-01
* 00:00:00 to 9999-12-31 23:59:59.999999. #GDateTime follows POSIX
* time in the sense that it is oblivious to leap seconds.
*
* #GDateTime is an immutable object; once it has been created it cannot
* be modified further. All modifiers will create a new #GDateTime.
* Nearly all such functions can fail due to the date or time going out
* of range, in which case %NULL will be returned.
*
* #GDateTime is reference counted: the reference count is increased by calling
* g_date_time_ref() and decreased by calling g_date_time_unref(). When the
* reference count drops to 0, the resources allocated by the #GDateTime
* structure are released.
*
* Many parts of the API may produce non-obvious results. As an
* example, adding two months to January 31st will yield March 31st
* whereas adding one month and then one month again will yield either
* March 28th or March 29th. Also note that adding 24 hours is not
* always the same as adding one day (since days containing daylight
* savings time transitions are either 23 or 25 hours in length).
*
* #GDateTime is available since GLib 2.26.
*/
struct _GDateTime
{
/* Microsecond timekeeping within Day */
guint64 usec;
/* TimeZone information */
GTimeZone *tz;
gint interval;
/* 1 is 0001-01-01 in Proleptic Gregorian */
gint32 days;
volatile gint ref_count;
};
/* Time conversion {{{1 */
#define UNIX_EPOCH_START 719163
#define INSTANT_TO_UNIX(instant) \
((instant)/USEC_PER_SECOND - UNIX_EPOCH_START * SEC_PER_DAY)
#define UNIX_TO_INSTANT(unix) \
(((unix) + UNIX_EPOCH_START * SEC_PER_DAY) * USEC_PER_SECOND)
#define DAYS_IN_4YEARS 1461 /* days in 4 years */
#define DAYS_IN_100YEARS 36524 /* days in 100 years */
#define DAYS_IN_400YEARS 146097 /* days in 400 years */
#define USEC_PER_SECOND (G_GINT64_CONSTANT (1000000))
#define USEC_PER_MINUTE (G_GINT64_CONSTANT (60000000))
#define USEC_PER_HOUR (G_GINT64_CONSTANT (3600000000))
#define USEC_PER_MILLISECOND (G_GINT64_CONSTANT (1000))
#define USEC_PER_DAY (G_GINT64_CONSTANT (86400000000))
#define SEC_PER_DAY (G_GINT64_CONSTANT (86400))
#define SECS_PER_MINUTE (60)
#define SECS_PER_HOUR (60 * SECS_PER_MINUTE)
#define SECS_PER_DAY (24 * SECS_PER_HOUR)
#define SECS_PER_YEAR (365 * SECS_PER_DAY)
#define SECS_PER_JULIAN (DAYS_PER_PERIOD * SECS_PER_DAY)
#define GREGORIAN_LEAP(y) ((((y) % 4) == 0) && (!((((y) % 100) == 0) && (((y) % 400) != 0))))
#define JULIAN_YEAR(d) ((d)->julian / 365.25)
#define DAYS_PER_PERIOD (G_GINT64_CONSTANT (2914695))
static const guint16 days_in_months[2][13] =
{
{ 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
{ 0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
};
static const guint16 days_in_year[2][13] =
{
{ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
};
#ifdef HAVE_LANGINFO_TIME
#define GET_AMPM(d) ((g_date_time_get_hour (d) < 12) ? \
nl_langinfo (AM_STR) : \
nl_langinfo (PM_STR))
#define PREFERRED_DATE_TIME_FMT nl_langinfo (D_T_FMT)
#define PREFERRED_DATE_FMT nl_langinfo (D_FMT)
#define PREFERRED_TIME_FMT nl_langinfo (T_FMT)
#define PREFERRED_TIME_FMT nl_langinfo (T_FMT)
#define PREFERRED_12HR_TIME_FMT nl_langinfo (T_FMT_AMPM)
static const gint weekday_item[2][7] =
{
{ ABDAY_2, ABDAY_3, ABDAY_4, ABDAY_5, ABDAY_6, ABDAY_7, ABDAY_1 },
{ DAY_2, DAY_3, DAY_4, DAY_5, DAY_6, DAY_7, DAY_1 }
};
static const gint month_item[2][12] =
{
{ ABMON_1, ABMON_2, ABMON_3, ABMON_4, ABMON_5, ABMON_6, ABMON_7, ABMON_8, ABMON_9, ABMON_10, ABMON_11, ABMON_12 },
{ MON_1, MON_2, MON_3, MON_4, MON_5, MON_6, MON_7, MON_8, MON_9, MON_10, MON_11, MON_12 },
};
#define WEEKDAY_ABBR(d) nl_langinfo (weekday_item[0][g_date_time_get_day_of_week (d) - 1])
#define WEEKDAY_FULL(d) nl_langinfo (weekday_item[1][g_date_time_get_day_of_week (d) - 1])
#define MONTH_ABBR(d) nl_langinfo (month_item[0][g_date_time_get_month (d) - 1])
#define MONTH_FULL(d) nl_langinfo (month_item[1][g_date_time_get_month (d) - 1])
#else
#define GET_AMPM(d) ((g_date_time_get_hour (d) < 12) \
/* Translators: 'before midday' indicator */ \
? C_("GDateTime", "AM") \
/* Translators: 'after midday' indicator */ \
: C_("GDateTime", "PM"))
/* Translators: this is the preferred format for expressing the date and the time */
#define PREFERRED_DATE_TIME_FMT C_("GDateTime", "%a %b %e %H:%M:%S %Y")
/* Translators: this is the preferred format for expressing the date */
#define PREFERRED_DATE_FMT C_("GDateTime", "%m/%d/%y")
/* Translators: this is the preferred format for expressing the time */
#define PREFERRED_TIME_FMT C_("GDateTime", "%H:%M:%S")
/* Translators: this is the preferred format for expressing 12 hour time */
#define PREFERRED_12HR_TIME_FMT C_("GDateTime", "%I:%M:%S %p")
#define WEEKDAY_ABBR(d) (get_weekday_name_abbr (g_date_time_get_day_of_week (d)))
#define WEEKDAY_FULL(d) (get_weekday_name (g_date_time_get_day_of_week (d)))
#define MONTH_ABBR(d) (get_month_name_abbr (g_date_time_get_month (d)))
#define MONTH_FULL(d) (get_month_name (g_date_time_get_month (d)))
static const gchar *
get_month_name (gint month)
{
switch (month)
{
case 1:
return C_("full month name", "January");
case 2:
return C_("full month name", "February");
case 3:
return C_("full month name", "March");
case 4:
return C_("full month name", "April");
case 5:
return C_("full month name", "May");
case 6:
return C_("full month name", "June");
case 7:
return C_("full month name", "July");
case 8:
return C_("full month name", "August");
case 9:
return C_("full month name", "September");
case 10:
return C_("full month name", "October");
case 11:
return C_("full month name", "November");
case 12:
return C_("full month name", "December");
default:
g_warning ("Invalid month number %d", month);
}
return NULL;
}
static const gchar *
get_month_name_abbr (gint month)
{
switch (month)
{
case 1:
return C_("abbreviated month name", "Jan");
case 2:
return C_("abbreviated month name", "Feb");
case 3:
return C_("abbreviated month name", "Mar");
case 4:
return C_("abbreviated month name", "Apr");
case 5:
return C_("abbreviated month name", "May");
case 6:
return C_("abbreviated month name", "Jun");
case 7:
return C_("abbreviated month name", "Jul");
case 8:
return C_("abbreviated month name", "Aug");
case 9:
return C_("abbreviated month name", "Sep");
case 10:
return C_("abbreviated month name", "Oct");
case 11:
return C_("abbreviated month name", "Nov");
case 12:
return C_("abbreviated month name", "Dec");
default:
g_warning ("Invalid month number %d", month);
}
return NULL;
}
static const gchar *
get_weekday_name (gint day)
{
switch (day)
{
case 1:
return C_("full weekday name", "Monday");
case 2:
return C_("full weekday name", "Tuesday");
case 3:
return C_("full weekday name", "Wednesday");
case 4:
return C_("full weekday name", "Thursday");
case 5:
return C_("full weekday name", "Friday");
case 6:
return C_("full weekday name", "Saturday");
case 7:
return C_("full weekday name", "Sunday");
default:
g_warning ("Invalid week day number %d", day);
}
return NULL;
}
static const gchar *
get_weekday_name_abbr (gint day)
{
switch (day)
{
case 1:
return C_("abbreviated weekday name", "Mon");
case 2:
return C_("abbreviated weekday name", "Tue");
case 3:
return C_("abbreviated weekday name", "Wed");
case 4:
return C_("abbreviated weekday name", "Thu");
case 5:
return C_("abbreviated weekday name", "Fri");
case 6:
return C_("abbreviated weekday name", "Sat");
case 7:
return C_("abbreviated weekday name", "Sun");
default:
g_warning ("Invalid week day number %d", day);
}
return NULL;
}
#endif /* HAVE_LANGINFO_TIME */
static inline gint
ymd_to_days (gint year,
gint month,
gint day)
{
gint64 days;
days = (year - 1) * 365 + ((year - 1) / 4) - ((year - 1) / 100)
+ ((year - 1) / 400);
days += days_in_year[0][month - 1];
if (GREGORIAN_LEAP (year) && month > 2)
day++;
days += day;
return days;
}
static void
g_date_time_get_week_number (GDateTime *datetime,
gint *week_number,
gint *day_of_week,
gint *day_of_year)
{
gint a, b, c, d, e, f, g, n, s, month, day, year;
g_date_time_get_ymd (datetime, &year, &month, &day);
if (month <= 2)
{
a = g_date_time_get_year (datetime) - 1;
b = (a / 4) - (a / 100) + (a / 400);
c = ((a - 1) / 4) - ((a - 1) / 100) + ((a - 1) / 400);
s = b - c;
e = 0;
f = day - 1 + (31 * (month - 1));
}
else
{
a = year;
b = (a / 4) - (a / 100) + (a / 400);
c = ((a - 1) / 4) - ((a - 1) / 100) + ((a - 1) / 400);
s = b - c;
e = s + 1;
f = day + (((153 * (month - 3)) + 2) / 5) + 58 + s;
}
g = (a + b) % 7;
d = (f + g - e) % 7;
n = f + 3 - d;
if (week_number)
{
if (n < 0)
*week_number = 53 - ((g - s) / 5);
else if (n > 364 + s)
*week_number = 1;
else
*week_number = (n / 7) + 1;
}
if (day_of_week)
*day_of_week = d + 1;
if (day_of_year)
*day_of_year = f + 1;
}
/* Lifecycle {{{1 */
static GDateTime *
g_date_time_alloc (GTimeZone *tz)
{
GDateTime *datetime;
datetime = g_slice_new0 (GDateTime);
datetime->tz = g_time_zone_ref (tz);
datetime->ref_count = 1;
return datetime;
}
/**
* g_date_time_ref:
* @datetime: a #GDateTime
*
* Atomically increments the reference count of @datetime by one.
*
* Return value: the #GDateTime with the reference count increased
*
* Since: 2.26
*/
GDateTime *
g_date_time_ref (GDateTime *datetime)
{
g_return_val_if_fail (datetime != NULL, NULL);
g_return_val_if_fail (datetime->ref_count > 0, NULL);
g_atomic_int_inc (&datetime->ref_count);
return datetime;
}
/**
* g_date_time_unref:
* @datetime: a #GDateTime
*
* Atomically decrements the reference count of @datetime by one.
*
* When the reference count reaches zero, the resources allocated by
* @datetime are freed
*
* Since: 2.26
*/
void
g_date_time_unref (GDateTime *datetime)
{
g_return_if_fail (datetime != NULL);
g_return_if_fail (datetime->ref_count > 0);
if (g_atomic_int_dec_and_test (&datetime->ref_count))
{
g_time_zone_unref (datetime->tz);
g_slice_free (GDateTime, datetime);
}
}
/* Internal state transformers {{{1 */
/*< internal >
* g_date_time_to_instant:
* @datetime: a #GDateTime
*
* Convert a @datetime into an instant.
*
* An instant is a number that uniquely describes a particular
* microsecond in time, taking time zone considerations into account.
* (ie: "03:00 -0400" is the same instant as "02:00 -0500").
*
* An instant is always positive but we use a signed return value to
* avoid troubles with C.
*/
static gint64
g_date_time_to_instant (GDateTime *datetime)
{
gint64 offset;
offset = g_time_zone_get_offset (datetime->tz, datetime->interval);
offset *= USEC_PER_SECOND;
return datetime->days * USEC_PER_DAY + datetime->usec - offset;
}
/*< internal >
* g_date_time_from_instant:
* @tz: a #GTimeZone
* @instant: a instant in time
*
* Creates a #GDateTime from a time zone and an instant.
*
* This might fail if the time ends up being out of range.
*/
static GDateTime *
g_date_time_from_instant (GTimeZone *tz,
gint64 instant)
{
GDateTime *datetime;
gint64 offset;
if (instant < 0 || instant > G_GINT64_CONSTANT (1000000000000000000))
return NULL;
datetime = g_date_time_alloc (tz);
datetime->interval = g_time_zone_find_interval (tz,
G_TIME_TYPE_UNIVERSAL,
INSTANT_TO_UNIX (instant));
offset = g_time_zone_get_offset (datetime->tz, datetime->interval);
offset *= USEC_PER_SECOND;
instant += offset;
datetime->days = instant / USEC_PER_DAY;
datetime->usec = instant % USEC_PER_DAY;
if (datetime->days < 1 || 3652059 < datetime->days)
{
g_date_time_unref (datetime);
datetime = NULL;
}
return datetime;
}
/*< internal >
* g_date_time_deal_with_date_change:
* @datetime: a #GDateTime
*
* This function should be called whenever the date changes by adding
* days, months or years. It does three things.
*
* First, we ensure that the date falls between 0001-01-01 and
* 9999-12-31 and return %FALSE if it does not.
*
* Next we update the ->interval field.
*
* Finally, we ensure that the resulting date and time pair exists (by
* ensuring that our time zone has an interval containing it) and
* adjusting as required. For example, if we have the time 02:30:00 on
* March 13 2010 in Toronto and we add 1 day to it, we would end up with
* 2:30am on March 14th, which doesn't exist. In that case, we bump the
* time up to 3:00am.
*/
static gboolean
g_date_time_deal_with_date_change (GDateTime *datetime)
{
GTimeType was_dst;
gint64 full_time;
gint64 usec;
if (datetime->days < 1 || datetime->days > 3652059)
return FALSE;
was_dst = g_time_zone_is_dst (datetime->tz, datetime->interval);
full_time = datetime->days * USEC_PER_DAY + datetime->usec;
usec = full_time % USEC_PER_SECOND;
full_time /= USEC_PER_SECOND;
full_time -= UNIX_EPOCH_START * SEC_PER_DAY;
datetime->interval = g_time_zone_adjust_time (datetime->tz,
was_dst,
&full_time);
full_time += UNIX_EPOCH_START * SEC_PER_DAY;
full_time *= USEC_PER_SECOND;
full_time += usec;
datetime->days = full_time / USEC_PER_DAY;
datetime->usec = full_time % USEC_PER_DAY;
/* maybe daylight time caused us to shift to a different day,
* but it definitely didn't push us into a different year */
return TRUE;
}
static GDateTime *
g_date_time_replace_days (GDateTime *datetime,
gint days)
{
GDateTime *new;
new = g_date_time_alloc (datetime->tz);
new->interval = datetime->interval;
new->usec = datetime->usec;
new->days = days;
if (!g_date_time_deal_with_date_change (new))
{
g_date_time_unref (new);
new = NULL;
}
return new;
}
/* now/unix/timeval Constructors {{{1 */
/*< internal >
* g_date_time_new_from_timeval:
* @tz: a #GTimeZone
* @tv: a #GTimeVal
*
* Creates a #GDateTime corresponding to the given #GTimeVal @tv in the
* given time zone @tz.
*
* The time contained in a #GTimeVal is always stored in the form of
* seconds elapsed since 1970-01-01 00:00:00 UTC, regardless of the
* given time zone.
*
* This call can fail (returning %NULL) if @tv represents a time outside
* of the supported range of #GDateTime.
*
* You should release the return value by calling g_date_time_unref()
* when you are done with it.
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
static GDateTime *
g_date_time_new_from_timeval (GTimeZone *tz,
const GTimeVal *tv)
{
return g_date_time_from_instant (tz, tv->tv_usec +
UNIX_TO_INSTANT (tv->tv_sec));
}
/*< internal >
* g_date_time_new_from_unix:
* @tz: a #GTimeZone
* @t: the Unix time
*
* Creates a #GDateTime corresponding to the given Unix time @t in the
* given time zone @tz.
*
* Unix time is the number of seconds that have elapsed since 1970-01-01
* 00:00:00 UTC, regardless of the time zone given.
*
* This call can fail (returning %NULL) if @t represents a time outside
* of the supported range of #GDateTime.
*
* You should release the return value by calling g_date_time_unref()
* when you are done with it.
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
static GDateTime *
g_date_time_new_from_unix (GTimeZone *tz,
gint64 secs)
{
return g_date_time_from_instant (tz, UNIX_TO_INSTANT (secs));
}
/**
* g_date_time_new_now:
* @tz: a #GTimeZone
*
* Creates a #GDateTime corresponding to this exact instant in the given
* time zone @tz. The time is as accurate as the system allows, to a
* maximum accuracy of 1 microsecond.
*
* This function will always succeed unless the system clock is set to
* truly insane values (or unless GLib is still being used after the
* year 9999).
*
* You should release the return value by calling g_date_time_unref()
* when you are done with it.
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_new_now (GTimeZone *tz)
{
GTimeVal tv;
g_get_current_time (&tv);
return g_date_time_new_from_timeval (tz, &tv);
}
/**
* g_date_time_new_now_local:
*
* Creates a #GDateTime corresponding to this exact instant in the local
* time zone.
*
* This is equivalent to calling g_date_time_new_now() with the time
* zone returned by g_time_zone_new_local().
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_new_now_local (void)
{
GDateTime *datetime;
GTimeZone *local;
local = g_time_zone_new_local ();
datetime = g_date_time_new_now (local);
g_time_zone_unref (local);
return datetime;
}
/**
* g_date_time_new_now_utc:
*
* Creates a #GDateTime corresponding to this exact instant in UTC.
*
* This is equivalent to calling g_date_time_new_now() with the time
* zone returned by g_time_zone_new_utc().
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_new_now_utc (void)
{
GDateTime *datetime;
GTimeZone *utc;
utc = g_time_zone_new_utc ();
datetime = g_date_time_new_now (utc);
g_time_zone_unref (utc);
return datetime;
}
/**
* g_date_time_new_from_unix_local:
* @t: the Unix time
*
* Creates a #GDateTime corresponding to the given Unix time @t in the
* local time zone.
*
* Unix time is the number of seconds that have elapsed since 1970-01-01
* 00:00:00 UTC, regardless of the local time offset.
*
* This call can fail (returning %NULL) if @t represents a time outside
* of the supported range of #GDateTime.
*
* You should release the return value by calling g_date_time_unref()
* when you are done with it.
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_new_from_unix_local (gint64 t)
{
GDateTime *datetime;
GTimeZone *local;
local = g_time_zone_new_local ();
datetime = g_date_time_new_from_unix (local, t);
g_time_zone_unref (local);
return datetime;
}
/**
* g_date_time_new_from_unix_utc:
* @t: the Unix time
*
* Creates a #GDateTime corresponding to the given Unix time @t in UTC.
*
* Unix time is the number of seconds that have elapsed since 1970-01-01
* 00:00:00 UTC.
*
* This call can fail (returning %NULL) if @t represents a time outside
* of the supported range of #GDateTime.
*
* You should release the return value by calling g_date_time_unref()
* when you are done with it.
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_new_from_unix_utc (gint64 t)
{
GDateTime *datetime;
GTimeZone *utc;
utc = g_time_zone_new_utc ();
datetime = g_date_time_new_from_unix (utc, t);
g_time_zone_unref (utc);
return datetime;
}
/**
* g_date_time_new_from_timeval_local:
* @tv: a #GTimeVal
*
* Creates a #GDateTime corresponding to the given #GTimeVal @tv in the
* local time zone.
*
* The time contained in a #GTimeVal is always stored in the form of
* seconds elapsed since 1970-01-01 00:00:00 UTC, regardless of the
* local time offset.
*
* This call can fail (returning %NULL) if @tv represents a time outside
* of the supported range of #GDateTime.
*
* You should release the return value by calling g_date_time_unref()
* when you are done with it.
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_new_from_timeval_local (const GTimeVal *tv)
{
GDateTime *datetime;
GTimeZone *local;
local = g_time_zone_new_local ();
datetime = g_date_time_new_from_timeval (local, tv);
g_time_zone_unref (local);
return datetime;
}
/**
* g_date_time_new_from_timeval_utc:
* @tv: a #GTimeVal
*
* Creates a #GDateTime corresponding to the given #GTimeVal @tv in UTC.
*
* The time contained in a #GTimeVal is always stored in the form of
* seconds elapsed since 1970-01-01 00:00:00 UTC.
*
* This call can fail (returning %NULL) if @tv represents a time outside
* of the supported range of #GDateTime.
*
* You should release the return value by calling g_date_time_unref()
* when you are done with it.
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_new_from_timeval_utc (const GTimeVal *tv)
{
GDateTime *datetime;
GTimeZone *utc;
utc = g_time_zone_new_utc ();
datetime = g_date_time_new_from_timeval (utc, tv);
g_time_zone_unref (utc);
return datetime;
}
/* full new functions {{{1 */
/**
* g_date_time_new:
* @tz: a #GTimeZone
* @year: the year component of the date
* @month: the month component of the date
* @day: the day component of the date
* @hour: the hour component of the date
* @minute: the minute component of the date
* @seconds: the number of seconds past the minute
*
* Creates a new #GDateTime corresponding to the given date and time in
* the time zone @tz.
*
* The @year must be between 1 and 9999, @month between 1 and 12 and @day
* between 1 and 28, 29, 30 or 31 depending on the month and the year.
*
* @hour must be between 0 and 23 and @minute must be between 0 and 59.
*
* @seconds must be at least 0.0 and must be strictly less than 60.0.
* It will be rounded down to the nearest microsecond.
*
* If the given time is not representable in the given time zone (for
* example, 02:30 on March 14th 2010 in Toronto, due to daylight savings
* time) then the time will be rounded up to the nearest existing time
* (in this case, 03:00). If this matters to you then you should verify
* the return value for containing the same as the numbers you gave.
*
* In the case that the given time is ambiguous in the given time zone
* (for example, 01:30 on November 7th 2010 in Toronto, due to daylight
* savings time) then the time falling within standard (ie:
* non-daylight) time is taken.
*
* It not considered a programmer error for the values to this function
* to be out of range, but in the case that they are, the function will
* return %NULL.
*
* You should release the return value by calling g_date_time_unref()
* when you are done with it.
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_new (GTimeZone *tz,
gint year,
gint month,
gint day,
gint hour,
gint minute,
gdouble seconds)
{
GDateTime *datetime;
gint64 full_time;
if (year < 1 || year > 9999 ||
month < 1 || month > 12 ||
day < 1 || day > 31 ||
hour < 0 || hour > 23 ||
minute < 0 || minute > 59 ||
seconds < 0.0 || seconds >= 60.0)
return NULL;
datetime = g_date_time_alloc (tz);
datetime->days = ymd_to_days (year, month, day);
datetime->usec = (hour * USEC_PER_HOUR)
+ (minute * USEC_PER_MINUTE)
+ (gint64) (seconds * USEC_PER_SECOND);
full_time = SEC_PER_DAY *
(ymd_to_days (year, month, day) - UNIX_EPOCH_START) +
SECS_PER_HOUR * hour +
SECS_PER_MINUTE * minute +
(int) seconds;
datetime->interval = g_time_zone_adjust_time (datetime->tz,
G_TIME_TYPE_STANDARD,
&full_time);
full_time += UNIX_EPOCH_START * SEC_PER_DAY;
datetime->days = full_time / SEC_PER_DAY;
datetime->usec = (full_time % SEC_PER_DAY) * USEC_PER_SECOND;
datetime->usec += ((int) (seconds * USEC_PER_SECOND)) % USEC_PER_SECOND;
return datetime;
}
/**
* g_date_time_new_local:
* @year: the year component of the date
* @month: the month component of the date
* @day: the day component of the date
* @hour: the hour component of the date
* @minute: the minute component of the date
* @seconds: the number of seconds past the minute
*
* Creates a new #GDateTime corresponding to the given date and time in
* the local time zone.
*
* This call is equivalent to calling g_date_time_new() with the time
* zone returned by g_time_zone_new_local().
*
* Returns: a #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_new_local (gint year,
gint month,
gint day,
gint hour,
gint minute,
gdouble seconds)
{
GDateTime *datetime;
GTimeZone *local;
local = g_time_zone_new_local ();
datetime = g_date_time_new (local, year, month, day, hour, minute, seconds);
g_time_zone_unref (local);
return datetime;
}
/**
* g_date_time_new_utc:
* @year: the year component of the date
* @month: the month component of the date
* @day: the day component of the date
* @hour: the hour component of the date
* @minute: the minute component of the date
* @seconds: the number of seconds past the minute
*
* Creates a new #GDateTime corresponding to the given date and time in
* UTC.
*
* This call is equivalent to calling g_date_time_new() with the time
* zone returned by g_time_zone_new_utc().
*
* Returns: a #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_new_utc (gint year,
gint month,
gint day,
gint hour,
gint minute,
gdouble seconds)
{
GDateTime *datetime;
GTimeZone *utc;
utc = g_time_zone_new_utc ();
datetime = g_date_time_new (utc, year, month, day, hour, minute, seconds);
g_time_zone_unref (utc);
return datetime;
}
/* Adders {{{1 */
/**
* g_date_time_add:
* @datetime: a #GDateTime
* @timespan: a #GTimeSpan
*
* Creates a copy of @datetime and adds the specified timespan to the copy.
*
* Return value: the newly created #GDateTime which should be freed with
* g_date_time_unref().
*
* Since: 2.26
*/
GDateTime*
g_date_time_add (GDateTime *datetime,
GTimeSpan timespan)
{
return g_date_time_from_instant (datetime->tz, timespan +
g_date_time_to_instant (datetime));
}
/**
* g_date_time_add_years:
* @datetime: a #GDateTime
* @years: the number of years
*
* Creates a copy of @datetime and adds the specified number of years to the
* copy. Add negative values to subtract years.
*
* Return value: the newly created #GDateTime which should be freed with
* g_date_time_unref().
*
* Since: 2.26
*/
GDateTime *
g_date_time_add_years (GDateTime *datetime,
gint years)
{
gint year, month, day;
g_return_val_if_fail (datetime != NULL, NULL);
if (years < -10000 || years > 10000)
return NULL;
g_date_time_get_ymd (datetime, &year, &month, &day);
year += years;
/* only possible issue is if we've entered a year with no February 29
*/
if (month == 2 && day == 29 && !GREGORIAN_LEAP (year))
day = 28;
return g_date_time_replace_days (datetime, ymd_to_days (year, month, day));
}
/**
* g_date_time_add_months:
* @datetime: a #GDateTime
* @months: the number of months
*
* Creates a copy of @datetime and adds the specified number of months to the
* copy. Add negative values to subtract months.
*
* Return value: the newly created #GDateTime which should be freed with
* g_date_time_unref().
*
* Since: 2.26
*/
GDateTime*
g_date_time_add_months (GDateTime *datetime,
gint months)
{
gint year, month, day;
g_return_val_if_fail (datetime != NULL, NULL);
g_date_time_get_ymd (datetime, &year, &month, &day);
if (months < -120000 || months > 120000)
return NULL;
year += months / 12;
month += months % 12;
if (month < 1)
{
month += 12;
year--;
}
else if (month > 12)
{
month -= 12;
year++;
}
day = MIN (day, days_in_months[GREGORIAN_LEAP (year)][month]);
return g_date_time_replace_days (datetime, ymd_to_days (year, month, day));
}
/**
* g_date_time_add_weeks:
* @datetime: a #GDateTime
* @weeks: the number of weeks
*
* Creates a copy of @datetime and adds the specified number of weeks to the
* copy. Add negative values to subtract weeks.
*
* Return value: the newly created #GDateTime which should be freed with
* g_date_time_unref().
*
* Since: 2.26
*/
GDateTime*
g_date_time_add_weeks (GDateTime *datetime,
gint weeks)
{
g_return_val_if_fail (datetime != NULL, NULL);
return g_date_time_add_days (datetime, weeks * 7);
}
/**
* g_date_time_add_days:
* @datetime: a #GDateTime
* @days: the number of days
*
* Creates a copy of @datetime and adds the specified number of days to the
* copy. Add negative values to subtract days.
*
* Return value: the newly created #GDateTime which should be freed with
* g_date_time_unref().
*
* Since: 2.26
*/
GDateTime*
g_date_time_add_days (GDateTime *datetime,
gint days)
{
g_return_val_if_fail (datetime != NULL, NULL);
if (days < -3660000 || days > 3660000)
return NULL;
return g_date_time_replace_days (datetime, datetime->days + days);
}
/**
* g_date_time_add_hours:
* @datetime: a #GDateTime
* @hours: the number of hours to add
*
* Creates a copy of @datetime and adds the specified number of hours.
* Add negative values to subtract hours.
*
* Return value: the newly created #GDateTime which should be freed with
* g_date_time_unref().
*
* Since: 2.26
*/
GDateTime*
g_date_time_add_hours (GDateTime *datetime,
gint hours)
{
return g_date_time_add (datetime, hours * USEC_PER_HOUR);
}
/**
* g_date_time_add_minutes:
* @datetime: a #GDateTime
* @minutes: the number of minutes to add
*
* Creates a copy of @datetime adding the specified number of minutes.
* Add negative values to subtract minutes.
*
* Return value: the newly created #GDateTime which should be freed with
* g_date_time_unref().
*
* Since: 2.26
*/
GDateTime*
g_date_time_add_minutes (GDateTime *datetime,
gint minutes)
{
return g_date_time_add (datetime, minutes * USEC_PER_MINUTE);
}
/**
* g_date_time_add_seconds:
* @datetime: a #GDateTime
* @seconds: the number of seconds to add
*
* Creates a copy of @datetime and adds the specified number of seconds.
* Add negative values to subtract seconds.
*
* Return value: the newly created #GDateTime which should be freed with
* g_date_time_unref().
*
* Since: 2.26
*/
GDateTime*
g_date_time_add_seconds (GDateTime *datetime,
gdouble seconds)
{
return g_date_time_add (datetime, seconds * USEC_PER_SECOND);
}
/**
* g_date_time_add_full:
* @datetime: a #GDateTime
* @years: the number of years to add
* @months: the number of months to add
* @days: the number of days to add
* @hours: the number of hours to add
* @minutes: the number of minutes to add
* @seconds: the number of seconds to add
*
* Creates a new #GDateTime adding the specified values to the current date and
* time in @datetime. Add negative values to subtract.
*
* Return value: the newly created #GDateTime that should be freed with
* g_date_time_unref().
*
* Since: 2.26
*/
GDateTime *
g_date_time_add_full (GDateTime *datetime,
gint years,
gint months,
gint days,
gint hours,
gint minutes,
gdouble seconds)
{
gint year, month, day;
gint64 full_time;
GDateTime *new;
gint interval;
g_return_val_if_fail (datetime != NULL, NULL);
g_date_time_get_ymd (datetime, &year, &month, &day);
months += years * 12;
if (months < -120000 || months > 120000)
return NULL;
if (days < -3660000 || days > 3660000)
return NULL;
year += months / 12;
month += months % 12;
if (month < 1)
{
month += 12;
year--;
}
else if (month > 12)
{
month -= 12;
year++;
}
day = MIN (day, days_in_months[GREGORIAN_LEAP (year)][month]);
/* full_time is now in unix (local) time */
full_time = datetime->usec / USEC_PER_SECOND + SEC_PER_DAY *
(ymd_to_days (year, month, day) + days - UNIX_EPOCH_START);
interval = g_time_zone_adjust_time (datetime->tz,
g_time_zone_is_dst (datetime->tz,
datetime->interval),
&full_time);
/* move to UTC unix time */
full_time -= g_time_zone_get_offset (datetime->tz, interval);
/* convert back to an instant, add back fractional seconds */
full_time += UNIX_EPOCH_START * SEC_PER_DAY;
full_time = full_time * USEC_PER_SECOND +
datetime->usec % USEC_PER_SECOND;
/* do the actual addition now */
full_time += (hours * USEC_PER_HOUR) +
(minutes * USEC_PER_MINUTE) +
(gint64) (seconds * USEC_PER_SECOND);
/* find the new interval */
interval = g_time_zone_find_interval (datetime->tz,
G_TIME_TYPE_UNIVERSAL,
INSTANT_TO_UNIX (full_time));
/* convert back into local time */
full_time += USEC_PER_SECOND *
g_time_zone_get_offset (datetime->tz, interval);
/* split into days and usec of a new datetime */
new = g_date_time_alloc (datetime->tz);
new->interval = interval;
new->days = full_time / USEC_PER_DAY;
new->usec = full_time % USEC_PER_DAY;
/* XXX validate */
return new;
}
/* Compare, difference, hash, equal {{{1 */
/**
* g_date_time_compare:
* @dt1: first #GDateTime to compare
* @dt2: second #GDateTime to compare
*
* A comparison function for #GDateTimes that is suitable
* as a #GCompareFunc. Both #GDateTimes must be non-%NULL.
*
* Return value: -1, 0 or 1 if @dt1 is less than, equal to or greater
* than @dt2.
*
* Since: 2.26
*/
gint
g_date_time_compare (gconstpointer dt1,
gconstpointer dt2)
{
gint64 difference;
difference = g_date_time_difference ((GDateTime *) dt1, (GDateTime *) dt2);
if (difference < 0)
return -1;
else if (difference > 0)
return 1;
else
return 0;
}
/**
* g_date_time_difference:
* @end: a #GDateTime
* @begin: a #GDateTime
*
* Calculates the difference in time between @end and @begin. The
* #GTimeSpan that is returned is effectively @end - @begin (ie:
* positive if the first parameter is larger).
*
* Return value: the difference between the two #GDateTime, as a time
* span expressed in microseconds.
*
* Since: 2.26
*/
GTimeSpan
g_date_time_difference (GDateTime *end,
GDateTime *begin)
{
g_return_val_if_fail (begin != NULL, 0);
g_return_val_if_fail (end != NULL, 0);
return g_date_time_to_instant (end) -
g_date_time_to_instant (begin);
}
/**
* g_date_time_hash:
* @datetime: a #GDateTime
*
* Hashes @datetime into a #guint, suitable for use within #GHashTable.
*
* Return value: a #guint containing the hash
*
* Since: 2.26
*/
guint
g_date_time_hash (gconstpointer datetime)
{
return g_date_time_to_instant ((GDateTime *) datetime);
}
/**
* g_date_time_equal:
* @dt1: a #GDateTime
* @dt2: a #GDateTime
*
* Checks to see if @dt1 and @dt2 are equal.
*
* Equal here means that they represent the same moment after converting
* them to the same time zone.
*
* Return value: %TRUE if @dt1 and @dt2 are equal
*
* Since: 2.26
*/
gboolean
g_date_time_equal (gconstpointer dt1,
gconstpointer dt2)
{
return g_date_time_difference ((GDateTime *) dt1, (GDateTime *) dt2) == 0;
}
/* Year, Month, Day Getters {{{1 */
/**
* g_date_time_get_ymd:
* @datetime: a #GDateTime.
* @year: (out) (allow-none): the return location for the gregorian year, or %NULL.
* @month: (out) (allow-none): the return location for the month of the year, or %NULL.
* @day: (out) (allow-none): the return location for the day of the month, or %NULL.
*
* Retrieves the Gregorian day, month, and year of a given #GDateTime.
*
* Since: 2.26
**/
void
g_date_time_get_ymd (GDateTime *datetime,
gint *year,
gint *month,
gint *day)
{
gint the_year;
gint the_month;
gint the_day;
gint remaining_days;
gint y100_cycles;
gint y4_cycles;
gint y1_cycles;
gint preceding;
gboolean leap;
g_return_if_fail (datetime != NULL);
remaining_days = datetime->days;
/*
* We need to convert an offset in days to its year/month/day representation.
* Leap years makes this a little trickier than it should be, so we use
* 400, 100 and 4 years cycles here to get to the correct year.
*/
/* Our days offset starts sets 0001-01-01 as day 1, if it was day 0 our
* math would be simpler, so let's do it */
remaining_days--;
the_year = (remaining_days / DAYS_IN_400YEARS) * 400 + 1;
remaining_days = remaining_days % DAYS_IN_400YEARS;
y100_cycles = remaining_days / DAYS_IN_100YEARS;
remaining_days = remaining_days % DAYS_IN_100YEARS;
the_year += y100_cycles * 100;
y4_cycles = remaining_days / DAYS_IN_4YEARS;
remaining_days = remaining_days % DAYS_IN_4YEARS;
the_year += y4_cycles * 4;
y1_cycles = remaining_days / 365;
the_year += y1_cycles;
remaining_days = remaining_days % 365;
if (y1_cycles == 4 || y100_cycles == 4) {
g_assert (remaining_days == 0);
/* special case that indicates that the date is actually one year before,
* in the 31th of December */
the_year--;
the_month = 12;
the_day = 31;
goto end;
}
/* now get the month and the day */
leap = y1_cycles == 3 && (y4_cycles != 24 || y100_cycles == 3);
g_assert (leap == GREGORIAN_LEAP(the_year));
the_month = (remaining_days + 50) >> 5;
preceding = (days_in_year[0][the_month - 1] + (the_month > 2 && leap));
if (preceding > remaining_days)
{
/* estimate is too large */
the_month -= 1;
preceding -= leap ? days_in_months[1][the_month]
: days_in_months[0][the_month];
}
remaining_days -= preceding;
g_assert(0 <= remaining_days);
the_day = remaining_days + 1;
end:
if (year)
*year = the_year;
if (month)
*month = the_month;
if (day)
*day = the_day;
}
/**
* g_date_time_get_year:
* @datetime: A #GDateTime
*
* Retrieves the year represented by @datetime in the Gregorian calendar.
*
* Return value: the year represented by @datetime
*
* Since: 2.26
*/
gint
g_date_time_get_year (GDateTime *datetime)
{
gint year;
g_return_val_if_fail (datetime != NULL, 0);
g_date_time_get_ymd (datetime, &year, NULL, NULL);
return year;
}
/**
* g_date_time_get_month:
* @datetime: a #GDateTime
*
* Retrieves the month of the year represented by @datetime in the Gregorian
* calendar.
*
* Return value: the month represented by @datetime
*
* Since: 2.26
*/
gint
g_date_time_get_month (GDateTime *datetime)
{
gint month;
g_return_val_if_fail (datetime != NULL, 0);
g_date_time_get_ymd (datetime, NULL, &month, NULL);
return month;
}
/**
* g_date_time_get_day_of_month:
* @datetime: a #GDateTime
*
* Retrieves the day of the month represented by @datetime in the gregorian
* calendar.
*
* Return value: the day of the month
*
* Since: 2.26
*/
gint
g_date_time_get_day_of_month (GDateTime *datetime)
{
gint day_of_year,
i;
const guint16 *days;
guint16 last = 0;
g_return_val_if_fail (datetime != NULL, 0);
days = days_in_year[GREGORIAN_LEAP (g_date_time_get_year (datetime)) ? 1 : 0];
g_date_time_get_week_number (datetime, NULL, NULL, &day_of_year);
for (i = 1; i <= 12; i++)
{
if (days [i] >= day_of_year)
return day_of_year - last;
last = days [i];
}
g_warn_if_reached ();
return 0;
}
/* Week of year / day of week getters {{{1 */
/**
* g_date_time_get_week_numbering_year:
* @datetime: a #GDateTime
*
* Returns the ISO 8601 week-numbering year in which the week containing
* @datetime falls.
*
* This function, taken together with g_date_time_get_week_of_year() and
* g_date_time_get_day_of_week() can be used to determine the full ISO
* week date on which @datetime falls.
*
* This is usually equal to the normal Gregorian year (as returned by
* g_date_time_get_year()), except as detailed below:
*
* For Thursday, the week-numbering year is always equal to the usual
* calendar year. For other days, the number is such that every day
* within a complete week (Monday to Sunday) is contained within the
* same week-numbering year.
*
* For Monday, Tuesday and Wednesday occurring near the end of the year,
* this may mean that the week-numbering year is one greater than the
* calendar year (so that these days have the same week-numbering year
* as the Thursday occurring early in the next year).
*
* For Friday, Saturaday and Sunday occurring near the start of the year,
* this may mean that the week-numbering year is one less than the
* calendar year (so that these days have the same week-numbering year
* as the Thursday occurring late in the previous year).
*
* An equivalent description is that the week-numbering year is equal to
* the calendar year containing the majority of the days in the current
* week (Monday to Sunday).
*
* Note that January 1 0001 in the proleptic Gregorian calendar is a
* Monday, so this function never returns 0.
*
* Returns: the ISO 8601 week-numbering year for @datetime
*
* Since: 2.26
**/
gint
g_date_time_get_week_numbering_year (GDateTime *datetime)
{
gint year, month, day, weekday;
g_date_time_get_ymd (datetime, &year, &month, &day);
weekday = g_date_time_get_day_of_week (datetime);
/* January 1, 2, 3 might be in the previous year if they occur after
* Thursday.
*
* Jan 1: Friday, Saturday, Sunday => day 1: weekday 5, 6, 7
* Jan 2: Saturday, Sunday => day 2: weekday 6, 7
* Jan 3: Sunday => day 3: weekday 7
*
* So we have a special case if (day - weekday) <= -4
*/
if (month == 1 && (day - weekday) <= -4)
return year - 1;
/* December 29, 30, 31 might be in the next year if they occur before
* Thursday.
*
* Dec 31: Monday, Tuesday, Wednesday => day 31: weekday 1, 2, 3
* Dec 30: Monday, Tuesday => day 30: weekday 1, 2
* Dec 29: Monday => day 29: weekday 1
*
* So we have a special case if (day - weekday) >= 28
*/
else if (month == 12 && (day - weekday) >= 28)
return year + 1;
else
return year;
}
/**
* g_date_time_get_week_of_year:
* @datetime: a #GDateTime
*
* Returns the ISO 8601 week number for the week containing @datetime.
* The ISO 8601 week number is the same for every day of the week (from
* Moday through Sunday). That can produce some unusual results
* (described below).
*
* The first week of the year is week 1. This is the week that contains
* the first Thursday of the year. Equivalently, this is the first week
* that has more than 4 of its days falling within the calendar year.
*
* The value 0 is never returned by this function. Days contained
* within a year but occurring before the first ISO 8601 week of that
* year are considered as being contained in the last week of the
* previous year. Similarly, the final days of a calendar year may be
* considered as being part of the first ISO 8601 week of the next year
* if 4 or more days of that week are contained within the new year.
*
* Returns: the ISO 8601 week number for @datetime.
*
* Since: 2.26
*/
gint
g_date_time_get_week_of_year (GDateTime *datetime)
{
gint weeknum;
g_return_val_if_fail (datetime != NULL, 0);
g_date_time_get_week_number (datetime, &weeknum, NULL, NULL);
return weeknum;
}
/**
* g_date_time_get_day_of_week:
* @datetime: a #GDateTime
*
* Retrieves the ISO 8601 day of the week on which @datetime falls (1 is
* Monday, 2 is Tuesday... 7 is Sunday).
*
* Return value: the day of the week
*
* Since: 2.26
*/
gint
g_date_time_get_day_of_week (GDateTime *datetime)
{
g_return_val_if_fail (datetime != NULL, 0);
return (datetime->days - 1) % 7 + 1;
}
/* Day of year getter {{{1 */
/**
* g_date_time_get_day_of_year:
* @datetime: a #GDateTime
*
* Retrieves the day of the year represented by @datetime in the Gregorian
* calendar.
*
* Return value: the day of the year
*
* Since: 2.26
*/
gint
g_date_time_get_day_of_year (GDateTime *datetime)
{
gint doy = 0;
g_return_val_if_fail (datetime != NULL, 0);
g_date_time_get_week_number (datetime, NULL, NULL, &doy);
return doy;
}
/* Time component getters {{{1 */
/**
* g_date_time_get_hour:
* @datetime: a #GDateTime
*
* Retrieves the hour of the day represented by @datetime
*
* Return value: the hour of the day
*
* Since: 2.26
*/
gint
g_date_time_get_hour (GDateTime *datetime)
{
g_return_val_if_fail (datetime != NULL, 0);
return (datetime->usec / USEC_PER_HOUR);
}
/**
* g_date_time_get_minute:
* @datetime: a #GDateTime
*
* Retrieves the minute of the hour represented by @datetime
*
* Return value: the minute of the hour
*
* Since: 2.26
*/
gint
g_date_time_get_minute (GDateTime *datetime)
{
g_return_val_if_fail (datetime != NULL, 0);
return (datetime->usec % USEC_PER_HOUR) / USEC_PER_MINUTE;
}
/**
* g_date_time_get_second:
* @datetime: a #GDateTime
*
* Retrieves the second of the minute represented by @datetime
*
* Return value: the second represented by @datetime
*
* Since: 2.26
*/
gint
g_date_time_get_second (GDateTime *datetime)
{
g_return_val_if_fail (datetime != NULL, 0);
return (datetime->usec % USEC_PER_MINUTE) / USEC_PER_SECOND;
}
/**
* g_date_time_get_microsecond:
* @datetime: a #GDateTime
*
* Retrieves the microsecond of the date represented by @datetime
*
* Return value: the microsecond of the second
*
* Since: 2.26
*/
gint
g_date_time_get_microsecond (GDateTime *datetime)
{
g_return_val_if_fail (datetime != NULL, 0);
return (datetime->usec % USEC_PER_SECOND);
}
/**
* g_date_time_get_seconds:
* @datetime: a #GDateTime
*
* Retrieves the number of seconds since the start of the last minute,
* including the fractional part.
*
* Returns: the number of seconds
*
* Since: 2.26
**/
gdouble
g_date_time_get_seconds (GDateTime *datetime)
{
g_return_val_if_fail (datetime != NULL, 0);
return (datetime->usec % USEC_PER_MINUTE) / 1000000.0;
}
/* Exporters {{{1 */
/**
* g_date_time_to_unix:
* @datetime: a #GDateTime
*
* Gives the Unix time corresponding to @datetime, rounding down to the
* nearest second.
*
* Unix time is the number of seconds that have elapsed since 1970-01-01
* 00:00:00 UTC, regardless of the time zone associated with @datetime.
*
* Returns: the Unix time corresponding to @datetime
*
* Since: 2.26
**/
gint64
g_date_time_to_unix (GDateTime *datetime)
{
return INSTANT_TO_UNIX (g_date_time_to_instant (datetime));
}
/**
* g_date_time_to_timeval:
* @datetime: a #GDateTime
* @tv: a #GTimeVal to modify
*
* Stores the instant in time that @datetime represents into @tv.
*
* The time contained in a #GTimeVal is always stored in the form of
* seconds elapsed since 1970-01-01 00:00:00 UTC, regardless of the time
* zone associated with @datetime.
*
* On systems where 'long' is 32bit (ie: all 32bit systems and all
* Windows systems), a #GTimeVal is incapable of storing the entire
* range of values that #GDateTime is capable of expressing. On those
* systems, this function returns %FALSE to indicate that the time is
* out of range.
*
* On systems where 'long' is 64bit, this function never fails.
*
* Returns: %TRUE if successful, else %FALSE
*
* Since: 2.26
**/
gboolean
g_date_time_to_timeval (GDateTime *datetime,
GTimeVal *tv)
{
tv->tv_sec = INSTANT_TO_UNIX (g_date_time_to_instant (datetime));
tv->tv_usec = datetime->usec % USEC_PER_SECOND;
return TRUE;
}
/* Timezone queries {{{1 */
/**
* g_date_time_get_utc_offset:
* @datetime: a #GDateTime
*
* Determines the offset to UTC in effect at the time and in the time
* zone of @datetime.
*
* The offset is the number of microseconds that you add to UTC time to
* arrive at local time for the time zone (ie: negative numbers for time
* zones west of GMT, positive numbers for east).
*
* If @datetime represents UTC time, then the offset is always zero.
*
* Returns: the number of microseconds that should be added to UTC to
* get the local time
*
* Since: 2.26
**/
GTimeSpan
g_date_time_get_utc_offset (GDateTime *datetime)
{
gint offset;
g_return_val_if_fail (datetime != NULL, 0);
offset = g_time_zone_get_offset (datetime->tz, datetime->interval);
return (gint64) offset * USEC_PER_SECOND;
}
/**
* g_date_time_get_timezone_abbreviation:
* @datetime: a #GDateTime
*
* Determines the time zone abbreviation to be used at the time and in
* the time zone of @datetime.
*
* For example, in Toronto this is currently "EST" during the winter
* months and "EDT" during the summer months when daylight savings
* time is in effect.
*
* Returns: (transfer none): the time zone abbreviation. The returned
* string is owned by the #GDateTime and it should not be
* modified or freed
*
* Since: 2.26
**/
const gchar *
g_date_time_get_timezone_abbreviation (GDateTime *datetime)
{
g_return_val_if_fail (datetime != NULL, NULL);
return g_time_zone_get_abbreviation (datetime->tz, datetime->interval);
}
/**
* g_date_time_is_daylight_savings:
* @datetime: a #GDateTime
*
* Determines if daylight savings time is in effect at the time and in
* the time zone of @datetime.
*
* Returns: %TRUE if daylight savings time is in effect
*
* Since: 2.26
**/
gboolean
g_date_time_is_daylight_savings (GDateTime *datetime)
{
g_return_val_if_fail (datetime != NULL, FALSE);
return g_time_zone_is_dst (datetime->tz, datetime->interval);
}
/* Timezone convert {{{1 */
/**
* g_date_time_to_timezone:
* @datetime: a #GDateTime
* @tz: the new #GTimeZone
*
* Create a new #GDateTime corresponding to the same instant in time as
* @datetime, but in the time zone @tz.
*
* This call can fail in the case that the time goes out of bounds. For
* example, converting 0001-01-01 00:00:00 UTC to a time zone west of
* Greenwich will fail (due to the year 0 being out of range).
*
* You should release the return value by calling g_date_time_unref()
* when you are done with it.
*
* Returns: a new #GDateTime, or %NULL
*
* Since: 2.26
**/
GDateTime *
g_date_time_to_timezone (GDateTime *datetime,
GTimeZone *tz)
{
return g_date_time_from_instant (tz, g_date_time_to_instant (datetime));
}
/**
* g_date_time_to_local:
* @datetime: a #GDateTime
*
* Creates a new #GDateTime corresponding to the same instant in time as
* @datetime, but in the local time zone.
*
* This call is equivalent to calling g_date_time_to_timezone() with the
* time zone returned by g_time_zone_new_local().
*
* Returns: the newly created #GDateTime
*
* Since: 2.26
**/
GDateTime *
g_date_time_to_local (GDateTime *datetime)
{
GDateTime *new;
GTimeZone *local;
local = g_time_zone_new_local ();
new = g_date_time_to_timezone (datetime, local);
g_time_zone_unref (local);
return new;
}
/**
* g_date_time_to_utc:
* @datetime: a #GDateTime
*
* Creates a new #GDateTime corresponding to the same instant in time as
* @datetime, but in UTC.
*
* This call is equivalent to calling g_date_time_to_timezone() with the
* time zone returned by g_time_zone_new_utc().
*
* Returns: the newly created #GDateTime
*
* Since: 2.26
**/
GDateTime *
g_date_time_to_utc (GDateTime *datetime)
{
GDateTime *new;
GTimeZone *utc;
utc = g_time_zone_new_utc ();
new = g_date_time_to_timezone (datetime, utc);
g_time_zone_unref (utc);
return new;
}
/* Format {{{1 */
static gboolean
format_z (GString *outstr,
gint offset,
guint colons)
{
gint hours;
gint minutes;
gint seconds;
hours = offset / 3600;
minutes = ABS (offset) / 60 % 60;
seconds = ABS (offset) % 60;
switch (colons)
{
case 0:
g_string_append_printf (outstr, "%+03d%02d",
hours,
minutes);
break;
case 1:
g_string_append_printf (outstr, "%+03d:%02d",
hours,
minutes);
break;
case 2:
g_string_append_printf (outstr, "%+03d:%02d:%02d",
hours,
minutes,
seconds);
break;
case 3:
g_string_append_printf (outstr, "%+03d", hours);
if (minutes != 0 || seconds != 0)
{
g_string_append_printf (outstr, ":%02d", minutes);
if (seconds != 0)
g_string_append_printf (outstr, ":%02d", seconds);
}
break;
default:
return FALSE;
}
return TRUE;
}
static void
format_number (GString *str,
gboolean use_alt_digits,
gchar *pad,
gint width,
guint32 number)
{
const gchar *ascii_digits[10] = {
"0", "1", "2", "3", "4", "5", "6", "7", "8", "9"
};
const gchar **digits = ascii_digits;
const gchar *tmp[10];
gint i = 0;
g_return_if_fail (width <= 10);
#ifdef HAVE_LANGINFO_OUTDIGIT
if (use_alt_digits)
{
static const gchar *alt_digits[10];
static gsize initialised;
/* 2^32 has 10 digits */
if G_UNLIKELY (g_once_init_enter (&initialised))
{
#define DO_DIGIT(n) \
alt_digits[n] = nl_langinfo (_NL_CTYPE_OUTDIGIT## n ##_MB)
DO_DIGIT(0); DO_DIGIT(1); DO_DIGIT(2); DO_DIGIT(3); DO_DIGIT(4);
DO_DIGIT(5); DO_DIGIT(6); DO_DIGIT(7); DO_DIGIT(8); DO_DIGIT(9);
#undef DO_DIGIT
g_once_init_leave (&initialised, TRUE);
}
digits = alt_digits;
}
#endif /* HAVE_LANGINFO_OUTDIGIT */
do
{
tmp[i++] = digits[number % 10];
number /= 10;
}
while (number);
while (pad && i < width)
tmp[i++] = *pad == '0' ? digits[0] : pad;
/* should really be impossible */
g_assert (i <= 10);
while (i)
g_string_append (str, tmp[--i]);
}
static gboolean g_date_time_format_locale (GDateTime *datetime,
const gchar *format,
GString *outstr,
gboolean locale_is_utf8);
/* g_date_time_format() subroutine that takes a locale-encoded format
* string and produces a locale-encoded date/time string.
*/
static gboolean
g_date_time_locale_format_locale (GDateTime *datetime,
const gchar *format,
GString *outstr,
gboolean locale_is_utf8)
{
gchar *utf8_format;
gboolean success;
if (locale_is_utf8)
return g_date_time_format_locale (datetime, format, outstr,
locale_is_utf8);
utf8_format = g_locale_to_utf8 (format, -1, NULL, NULL, NULL);
if (!utf8_format)
return FALSE;
success = g_date_time_format_locale (datetime, utf8_format, outstr,
locale_is_utf8);
g_free (utf8_format);
return success;
}
/* g_date_time_format() subroutine that takes a UTF-8 format
* string and produces a locale-encoded date/time string.
*/
static gboolean
g_date_time_format_locale (GDateTime *datetime,
const gchar *format,
GString *outstr,
gboolean locale_is_utf8)
{
guint len;
guint colons;
gchar *tmp;
gunichar c;
gboolean alt_digits = FALSE;
gboolean pad_set = FALSE;
gchar *pad = "";
gchar *ampm;
const gchar *tz;
while (*format)
{
len = strcspn (format, "%");
if (len)
{
if (locale_is_utf8)
g_string_append_len (outstr, format, len);
else
{
tmp = g_locale_from_utf8 (format, len, NULL, NULL, NULL);
if (!tmp)
return FALSE;
g_string_append (outstr, tmp);
g_free (tmp);
}
}
format += len;
if (!*format)
break;
g_assert (*format == '%');
format++;
if (!*format)
break;
colons = 0;
alt_digits = FALSE;
pad_set = FALSE;
next_mod:
c = g_utf8_get_char (format);
format = g_utf8_next_char (format);
switch (c)
{
case 'a':
g_string_append (outstr, WEEKDAY_ABBR (datetime));
break;
case 'A':
g_string_append (outstr, WEEKDAY_FULL (datetime));
break;
case 'b':
g_string_append (outstr, MONTH_ABBR (datetime));
break;
case 'B':
g_string_append (outstr, MONTH_FULL (datetime));
break;
case 'c':
{
if (!g_date_time_locale_format_locale (datetime, PREFERRED_DATE_TIME_FMT,
outstr, locale_is_utf8))
return FALSE;
}
break;
case 'C':
format_number (outstr, alt_digits, pad_set ? pad : "0", 2,
g_date_time_get_year (datetime) / 100);
break;
case 'd':
format_number (outstr, alt_digits, pad_set ? pad : "0", 2,
g_date_time_get_day_of_month (datetime));
break;
case 'e':
format_number (outstr, alt_digits, pad_set ? pad : " ", 2,
g_date_time_get_day_of_month (datetime));
break;
case 'F':
g_string_append_printf (outstr, "%d-%02d-%02d",
g_date_time_get_year (datetime),
g_date_time_get_month (datetime),
g_date_time_get_day_of_month (datetime));
break;
case 'g':
format_number (outstr, alt_digits, pad_set ? pad : "0", 2,
g_date_time_get_week_numbering_year (datetime) % 100);
break;
case 'G':
format_number (outstr, alt_digits, pad_set ? pad : 0, 0,
g_date_time_get_week_numbering_year (datetime));
break;
case 'h':
g_string_append (outstr, MONTH_ABBR (datetime));
break;
case 'H':
format_number (outstr, alt_digits, pad_set ? pad : "0", 2,
g_date_time_get_hour (datetime));
break;
case 'I':
format_number (outstr, alt_digits, pad_set ? pad : "0", 2,
(g_date_time_get_hour (datetime) + 11) % 12 + 1);
break;
case 'j':
format_number (outstr, alt_digits, pad_set ? pad : "0", 3,
g_date_time_get_day_of_year (datetime));
break;
case 'k':
format_number (outstr, alt_digits, pad_set ? pad : " ", 2,
g_date_time_get_hour (datetime));
break;
case 'l':
format_number (outstr, alt_digits, pad_set ? pad : " ", 2,
(g_date_time_get_hour (datetime) + 11) % 12 + 1);
break;
case 'n':
g_string_append_c (outstr, '\n');
break;
case 'm':
format_number (outstr, alt_digits, pad_set ? pad : "0", 2,
g_date_time_get_month (datetime));
break;
case 'M':
format_number (outstr, alt_digits, pad_set ? pad : "0", 2,
g_date_time_get_minute (datetime));
break;
case 'O':
alt_digits = TRUE;
goto next_mod;
case 'p':
ampm = (gchar *) GET_AMPM (datetime);
if (!locale_is_utf8)
{
ampm = tmp = g_locale_to_utf8 (ampm, -1, NULL, NULL, NULL);
if (!tmp)
return FALSE;
}
ampm = g_utf8_strup (ampm, -1);
if (!locale_is_utf8)
{
g_free (tmp);
tmp = g_locale_from_utf8 (ampm, -1, NULL, NULL, NULL);
g_free (ampm);
if (!tmp)
return FALSE;
ampm = tmp;
}
g_string_append (outstr, ampm);
g_free (ampm);
break;
case 'P':
ampm = (gchar *) GET_AMPM (datetime);
if (!locale_is_utf8)
{
ampm = tmp = g_locale_to_utf8 (ampm, -1, NULL, NULL, NULL);
if (!tmp)
return FALSE;
}
ampm = g_utf8_strdown (ampm, -1);
if (!locale_is_utf8)
{
g_free (tmp);
tmp = g_locale_from_utf8 (ampm, -1, NULL, NULL, NULL);
g_free (ampm);
if (!tmp)
return FALSE;
ampm = tmp;
}
g_string_append (outstr, ampm);
g_free (ampm);
break;
case 'r':
{
if (!g_date_time_locale_format_locale (datetime, PREFERRED_12HR_TIME_FMT,
outstr, locale_is_utf8))
return FALSE;
}
break;
case 'R':
g_string_append_printf (outstr, "%02d:%02d",
g_date_time_get_hour (datetime),
g_date_time_get_minute (datetime));
break;
case 's':
g_string_append_printf (outstr, "%" G_GINT64_FORMAT, g_date_time_to_unix (datetime));
break;
case 'S':
format_number (outstr, alt_digits, pad_set ? pad : "0", 2,
g_date_time_get_second (datetime));
break;
case 't':
g_string_append_c (outstr, '\t');
break;
case 'T':
g_string_append_printf (outstr, "%02d:%02d:%02d",
g_date_time_get_hour (datetime),
g_date_time_get_minute (datetime),
g_date_time_get_second (datetime));
break;
case 'u':
format_number (outstr, alt_digits, 0, 0,
g_date_time_get_day_of_week (datetime));
break;
case 'V':
format_number (outstr, alt_digits, pad_set ? pad : "0", 2,
g_date_time_get_week_of_year (datetime));
break;
case 'w':
format_number (outstr, alt_digits, 0, 0,
g_date_time_get_day_of_week (datetime) % 7);
break;
case 'x':
{
if (!g_date_time_locale_format_locale (datetime, PREFERRED_DATE_FMT,
outstr, locale_is_utf8))
return FALSE;
}
break;
case 'X':
{
if (!g_date_time_locale_format_locale (datetime, PREFERRED_TIME_FMT,
outstr, locale_is_utf8))
return FALSE;
}
break;
case 'y':
format_number (outstr, alt_digits, pad_set ? pad : "0", 2,
g_date_time_get_year (datetime) % 100);
break;
case 'Y':
format_number (outstr, alt_digits, 0, 0,
g_date_time_get_year (datetime));
break;
case 'z':
{
gint64 offset;
if (datetime->tz != NULL)
offset = g_date_time_get_utc_offset (datetime) / USEC_PER_SECOND;
else
offset = 0;
if (!format_z (outstr, (int) offset, colons))
return FALSE;
}
break;
case 'Z':
tz = g_date_time_get_timezone_abbreviation (datetime);
if (!locale_is_utf8)
{
tz = tmp = g_locale_from_utf8 (tz, -1, NULL, NULL, NULL);
if (!tmp)
return FALSE;
}
g_string_append (outstr, tz);
if (!locale_is_utf8)
g_free (tmp);
break;
case '%':
g_string_append_c (outstr, '%');
break;
case '-':
pad_set = TRUE;
pad = "";
goto next_mod;
case '_':
pad_set = TRUE;
pad = " ";
goto next_mod;
case '0':
pad_set = TRUE;
pad = "0";
goto next_mod;
case ':':
/* Colons are only allowed before 'z' */
if (*format && *format != 'z' && *format != ':')
return FALSE;
colons++;
goto next_mod;
default:
return FALSE;
}
}
return TRUE;
}
/**
* g_date_time_format:
* @datetime: A #GDateTime
* @format: a valid UTF-8 string, containing the format for the
* #GDateTime
*
* Creates a newly allocated string representing the requested @format.
*
* The format strings understood by this function are a subset of the
* strftime() format language as specified by C99. The \%D, \%U and \%W
* conversions are not supported, nor is the 'E' modifier. The GNU
* extensions \%k, \%l, \%s and \%P are supported, however, as are the
* '0', '_' and '-' modifiers.
*
* In contrast to strftime(), this function always produces a UTF-8
* string, regardless of the current locale. Note that the rendering of
* many formats is locale-dependent and may not match the strftime()
* output exactly.
*
* The following format specifiers are supported:
*
* <variablelist>
* <varlistentry><term>
* <literal>\%a</literal>:
* </term><listitem><simpara>
* the abbreviated weekday name according to the current locale
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%A</literal>:
* </term><listitem><simpara>
* the full weekday name according to the current locale
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%b</literal>:
* </term><listitem><simpara>
* the abbreviated month name according to the current locale
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%B</literal>:
* </term><listitem><simpara>
* the full month name according to the current locale
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%c</literal>:
* </term><listitem><simpara>
* the preferred date and time representation for the current locale
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%C</literal>:
* </term><listitem><simpara>
* The century number (year/100) as a 2-digit integer (00-99)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%d</literal>:
* </term><listitem><simpara>
* the day of the month as a decimal number (range 01 to 31)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%e</literal>:
* </term><listitem><simpara>
* the day of the month as a decimal number (range 1 to 31)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%F</literal>:
* </term><listitem><simpara>
* equivalent to <literal>\%Y-\%m-\%d</literal> (the ISO 8601 date
* format)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%g</literal>:
* </term><listitem><simpara>
* the last two digits of the ISO 8601 week-based year as a decimal
* number (00-99). This works well with \%V and \%u.
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%G</literal>:
* </term><listitem><simpara>
* the ISO 8601 week-based year as a decimal number. This works well
* with \%V and \%u.
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%h</literal>:
* </term><listitem><simpara>
* equivalent to <literal>\%b</literal>
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%H</literal>:
* </term><listitem><simpara>
* the hour as a decimal number using a 24-hour clock (range 00 to
* 23)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%I</literal>:
* </term><listitem><simpara>
* the hour as a decimal number using a 12-hour clock (range 01 to
* 12)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%j</literal>:
* </term><listitem><simpara>
* the day of the year as a decimal number (range 001 to 366)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%k</literal>:
* </term><listitem><simpara>
* the hour (24-hour clock) as a decimal number (range 0 to 23);
* single digits are preceded by a blank
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%l</literal>:
* </term><listitem><simpara>
* the hour (12-hour clock) as a decimal number (range 1 to 12);
* single digits are preceded by a blank
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%m</literal>:
* </term><listitem><simpara>
* the month as a decimal number (range 01 to 12)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%M</literal>:
* </term><listitem><simpara>
* the minute as a decimal number (range 00 to 59)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%p</literal>:
* </term><listitem><simpara>
* either "AM" or "PM" according to the given time value, or the
* corresponding strings for the current locale. Noon is treated as
* "PM" and midnight as "AM".
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%P</literal>:
* </term><listitem><simpara>
* like \%p but lowercase: "am" or "pm" or a corresponding string for
* the current locale
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%r</literal>:
* </term><listitem><simpara>
* the time in a.m. or p.m. notation
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%R</literal>:
* </term><listitem><simpara>
* the time in 24-hour notation (<literal>\%H:\%M</literal>)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%s</literal>:
* </term><listitem><simpara>
* the number of seconds since the Epoch, that is, since 1970-01-01
* 00:00:00 UTC
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%S</literal>:
* </term><listitem><simpara>
* the second as a decimal number (range 00 to 60)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%t</literal>:
* </term><listitem><simpara>
* a tab character
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%T</literal>:
* </term><listitem><simpara>
* the time in 24-hour notation with seconds (<literal>\%H:\%M:\%S</literal>)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%u</literal>:
* </term><listitem><simpara>
* the ISO 8601 standard day of the week as a decimal, range 1 to 7,
* Monday being 1. This works well with \%G and \%V.
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%V</literal>:
* </term><listitem><simpara>
* the ISO 8601 standard week number of the current year as a decimal
* number, range 01 to 53, where week 1 is the first week that has at
* least 4 days in the new year. See g_date_time_get_week_of_year().
* This works well with \%G and \%u.
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%w</literal>:
* </term><listitem><simpara>
* the day of the week as a decimal, range 0 to 6, Sunday being 0.
* This is not the ISO 8601 standard format -- use \%u instead.
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%x</literal>:
* </term><listitem><simpara>
* the preferred date representation for the current locale without
* the time
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%X</literal>:
* </term><listitem><simpara>
* the preferred time representation for the current locale without
* the date
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%y</literal>:
* </term><listitem><simpara>
* the year as a decimal number without the century
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%Y</literal>:
* </term><listitem><simpara>
* the year as a decimal number including the century
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%z</literal>:
* </term><listitem><simpara>
* the time zone as an offset from UTC (+hhmm)
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%:z</literal>:
* </term><listitem><simpara>
* the time zone as an offset from UTC (+hh:mm). This is a gnulib strftime extension. Since: 2.38
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%::z</literal>:
* </term><listitem><simpara>
* the time zone as an offset from UTC (+hh:mm:ss). This is a gnulib strftime extension. Since: 2.38
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%:::z</literal>:
* </term><listitem><simpara>
* the time zone as an offset from UTC, with : to necessary precision
* (e.g., -04, +05:30). This is a gnulib strftime extension. Since: 2.38
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%Z</literal>:
* </term><listitem><simpara>
* the time zone or name or abbreviation
* </simpara></listitem></varlistentry>
* <varlistentry><term>
* <literal>\%\%</literal>:
* </term><listitem><simpara>
* a literal <literal>\%</literal> character
* </simpara></listitem></varlistentry>
* </variablelist>
*
* Some conversion specifications can be modified by preceding the
* conversion specifier by one or more modifier characters. The
* following modifiers are supported for many of the numeric
* conversions:
* <variablelist>
* <varlistentry>
* <term>O</term>
* <listitem>
* Use alternative numeric symbols, if the current locale
* supports those.
* </listitem>
* </varlistentry>
* <varlistentry>
* <term>_</term>
* <listitem>
* Pad a numeric result with spaces.
* This overrides the default padding for the specifier.
* </listitem>
* </varlistentry>
* <varlistentry>
* <term>-</term>
* <listitem>
* Do not pad a numeric result.
* This overrides the default padding for the specifier.
* </listitem>
* </varlistentry>
* <varlistentry>
* <term>0</term>
* <listitem>
* Pad a numeric result with zeros.
* This overrides the default padding for the specifier.
* </listitem>
* </varlistentry>
* </variablelist>
*
* Returns: a newly allocated string formatted to the requested format
* or %NULL in the case that there was an error. The string
* should be freed with g_free().
*
* Since: 2.26
*/
gchar *
g_date_time_format (GDateTime *datetime,
const gchar *format)
{
GString *outstr;
gchar *utf8;
gboolean locale_is_utf8 = g_get_charset (NULL);
g_return_val_if_fail (datetime != NULL, NULL);
g_return_val_if_fail (format != NULL, NULL);
g_return_val_if_fail (g_utf8_validate (format, -1, NULL), NULL);
outstr = g_string_sized_new (strlen (format) * 2);
if (!g_date_time_format_locale (datetime, format, outstr, locale_is_utf8))
{
g_string_free (outstr, TRUE);
return NULL;
}
if (locale_is_utf8)
return g_string_free (outstr, FALSE);
utf8 = g_locale_to_utf8 (outstr->str, outstr->len, NULL, NULL, NULL);
g_string_free (outstr, TRUE);
return utf8;
}
/* Epilogue {{{1 */
/* vim:set foldmethod=marker: */