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glib/glib/gdate.c
Philip Withnall 45b74b02b8 gdate: Deprecate methods which use GTimeVal 
GTimeVal is not year-2038-safe.

Signed-off-by: Philip Withnall <withnall@endlessm.com>

Helps: #1438
2019-07-29 12:27:29 +01:00

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/* GLIB - Library of useful routines for C programming
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* 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 License, or (at your option) any later version.
*
* This library 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, see <http://www.gnu.org/licenses/>.
*/
/*
* Modified by the GLib Team and others 1997-2000. See the AUTHORS
* file for a list of people on the GLib Team. See the ChangeLog
* files for a list of changes. These files are distributed with
* GLib at ftp://ftp.gtk.org/pub/gtk/.
*/
/*
* MT safe
*/
#include "config.h"
#include "glibconfig.h"
#define DEBUG_MSG(x) /* */
#ifdef G_ENABLE_DEBUG
/* #define DEBUG_MSG(args) g_message args ; */
#endif
#include <time.h>
#include <string.h>
#include <stdlib.h>
#include <locale.h>
#ifdef G_OS_WIN32
#include <windows.h>
#endif
#include "gdate.h"
#include "gconvert.h"
#include "gmem.h"
#include "gstrfuncs.h"
#include "gtestutils.h"
#include "gthread.h"
#include "gunicode.h"
#ifdef G_OS_WIN32
#include "garray.h"
#endif
/**
* SECTION:date
* @title: Date and Time Functions
* @short_description: calendrical calculations and miscellaneous time stuff
*
* The #GDate data structure represents a day between January 1, Year 1,
* and sometime a few thousand years in the future (right now it will go
* to the year 65535 or so, but g_date_set_parse() only parses up to the
* year 8000 or so - just count on "a few thousand"). #GDate is meant to
* represent everyday dates, not astronomical dates or historical dates
* or ISO timestamps or the like. It extrapolates the current Gregorian
* calendar forward and backward in time; there is no attempt to change
* the calendar to match time periods or locations. #GDate does not store
* time information; it represents a day.
*
* The #GDate implementation has several nice features; it is only a
* 64-bit struct, so storing large numbers of dates is very efficient. It
* can keep both a Julian and day-month-year representation of the date,
* since some calculations are much easier with one representation or the
* other. A Julian representation is simply a count of days since some
* fixed day in the past; for #GDate the fixed day is January 1, 1 AD.
* ("Julian" dates in the #GDate API aren't really Julian dates in the
* technical sense; technically, Julian dates count from the start of the
* Julian period, Jan 1, 4713 BC).
*
* #GDate is simple to use. First you need a "blank" date; you can get a
* dynamically allocated date from g_date_new(), or you can declare an
* automatic variable or array and initialize it to a sane state by
* calling g_date_clear(). A cleared date is sane; it's safe to call
* g_date_set_dmy() and the other mutator functions to initialize the
* value of a cleared date. However, a cleared date is initially
* invalid, meaning that it doesn't represent a day that exists.
* It is undefined to call any of the date calculation routines on an
* invalid date. If you obtain a date from a user or other
* unpredictable source, you should check its validity with the
* g_date_valid() predicate. g_date_valid() is also used to check for
* errors with g_date_set_parse() and other functions that can
* fail. Dates can be invalidated by calling g_date_clear() again.
*
* It is very important to use the API to access the #GDate
* struct. Often only the day-month-year or only the Julian
* representation is valid. Sometimes neither is valid. Use the API.
*
* GLib also features #GDateTime which represents a precise time.
*/
/**
* G_USEC_PER_SEC:
*
* Number of microseconds in one second (1 million).
* This macro is provided for code readability.
*/
/**
* GTimeVal:
* @tv_sec: seconds
* @tv_usec: microseconds
*
* Represents a precise time, with seconds and microseconds.
* Similar to the struct timeval returned by the gettimeofday()
* UNIX system call.
*
* GLib is attempting to unify around the use of 64-bit integers to
* represent microsecond-precision time. As such, this type will be
* removed from a future version of GLib. A consequence of using `glong` for
* `tv_sec` is that on 32-bit systems `GTimeVal` is subject to the year 2038
* problem.
*
* Deprecated: 2.62: Use #GDateTime or #guint64 instead.
*/
/**
* GDate:
* @julian_days: the Julian representation of the date
* @julian: this bit is set if @julian_days is valid
* @dmy: this is set if @day, @month and @year are valid
* @day: the day of the day-month-year representation of the date,
* as a number between 1 and 31
* @month: the day of the day-month-year representation of the date,
* as a number between 1 and 12
* @year: the day of the day-month-year representation of the date
*
* Represents a day between January 1, Year 1 and a few thousand years in
* the future. None of its members should be accessed directly.
*
* If the #GDate-struct is obtained from g_date_new(), it will be safe
* to mutate but invalid and thus not safe for calendrical computations.
*
* If it's declared on the stack, it will contain garbage so must be
* initialized with g_date_clear(). g_date_clear() makes the date invalid
* but sane. An invalid date doesn't represent a day, it's "empty." A date
* becomes valid after you set it to a Julian day or you set a day, month,
* and year.
*/
/**
* GTime:
*
* Simply a replacement for `time_t`. It has been deprecated
* since it is not equivalent to `time_t` on 64-bit platforms
* with a 64-bit `time_t`. Unrelated to #GTimer.
*
* Note that #GTime is defined to always be a 32-bit integer,
* unlike `time_t` which may be 64-bit on some systems. Therefore,
* #GTime will overflow in the year 2038, and you cannot use the
* address of a #GTime variable as argument to the UNIX time()
* function.
*
* Instead, do the following:
* |[<!-- language="C" -->
* time_t ttime;
* GTime gtime;
*
* time (&ttime);
* gtime = (GTime)ttime;
* ]|
*
* Deprecated: 2.62: This is not [Y2038-safe](https://en.wikipedia.org/wiki/Year_2038_problem).
* Use #GDateTime or #time_t instead.
*/
/**
* GDateDMY:
* @G_DATE_DAY: a day
* @G_DATE_MONTH: a month
* @G_DATE_YEAR: a year
*
* This enumeration isn't used in the API, but may be useful if you need
* to mark a number as a day, month, or year.
*/
/**
* GDateDay:
*
* Integer representing a day of the month; between 1 and 31.
* #G_DATE_BAD_DAY represents an invalid day of the month.
*/
/**
* GDateMonth:
* @G_DATE_BAD_MONTH: invalid value
* @G_DATE_JANUARY: January
* @G_DATE_FEBRUARY: February
* @G_DATE_MARCH: March
* @G_DATE_APRIL: April
* @G_DATE_MAY: May
* @G_DATE_JUNE: June
* @G_DATE_JULY: July
* @G_DATE_AUGUST: August
* @G_DATE_SEPTEMBER: September
* @G_DATE_OCTOBER: October
* @G_DATE_NOVEMBER: November
* @G_DATE_DECEMBER: December
*
* Enumeration representing a month; values are #G_DATE_JANUARY,
* #G_DATE_FEBRUARY, etc. #G_DATE_BAD_MONTH is the invalid value.
*/
/**
* GDateYear:
*
* Integer representing a year; #G_DATE_BAD_YEAR is the invalid
* value. The year must be 1 or higher; negative (BC) years are not
* allowed. The year is represented with four digits.
*/
/**
* GDateWeekday:
* @G_DATE_BAD_WEEKDAY: invalid value
* @G_DATE_MONDAY: Monday
* @G_DATE_TUESDAY: Tuesday
* @G_DATE_WEDNESDAY: Wednesday
* @G_DATE_THURSDAY: Thursday
* @G_DATE_FRIDAY: Friday
* @G_DATE_SATURDAY: Saturday
* @G_DATE_SUNDAY: Sunday
*
* Enumeration representing a day of the week; #G_DATE_MONDAY,
* #G_DATE_TUESDAY, etc. #G_DATE_BAD_WEEKDAY is an invalid weekday.
*/
/**
* G_DATE_BAD_DAY:
*
* Represents an invalid #GDateDay.
*/
/**
* G_DATE_BAD_JULIAN:
*
* Represents an invalid Julian day number.
*/
/**
* G_DATE_BAD_YEAR:
*
* Represents an invalid year.
*/
/**
* g_date_new:
*
* Allocates a #GDate and initializes
* it to a sane state. The new date will
* be cleared (as if you'd called g_date_clear()) but invalid (it won't
* represent an existing day). Free the return value with g_date_free().
*
* Returns: a newly-allocated #GDate
*/
GDate*
g_date_new (void)
{
GDate *d = g_new0 (GDate, 1); /* happily, 0 is the invalid flag for everything. */
return d;
}
/**
* g_date_new_dmy:
* @day: day of the month
* @month: month of the year
* @year: year
*
* Like g_date_new(), but also sets the value of the date. Assuming the
* day-month-year triplet you pass in represents an existing day, the
* returned date will be valid.
*
* Returns: a newly-allocated #GDate initialized with @day, @month, and @year
*/
GDate*
g_date_new_dmy (GDateDay day,
GDateMonth m,
GDateYear y)
{
GDate *d;
g_return_val_if_fail (g_date_valid_dmy (day, m, y), NULL);
d = g_new (GDate, 1);
d->julian = FALSE;
d->dmy = TRUE;
d->month = m;
d->day = day;
d->year = y;
g_assert (g_date_valid (d));
return d;
}
/**
* g_date_new_julian:
* @julian_day: days since January 1, Year 1
*
* Like g_date_new(), but also sets the value of the date. Assuming the
* Julian day number you pass in is valid (greater than 0, less than an
* unreasonably large number), the returned date will be valid.
*
* Returns: a newly-allocated #GDate initialized with @julian_day
*/
GDate*
g_date_new_julian (guint32 julian_day)
{
GDate *d;
g_return_val_if_fail (g_date_valid_julian (julian_day), NULL);
d = g_new (GDate, 1);
d->julian = TRUE;
d->dmy = FALSE;
d->julian_days = julian_day;
g_assert (g_date_valid (d));
return d;
}
/**
* g_date_free:
* @date: a #GDate to free
*
* Frees a #GDate returned from g_date_new().
*/
void
g_date_free (GDate *date)
{
g_return_if_fail (date != NULL);
g_free (date);
}
/**
* g_date_copy:
* @date: a #GDate to copy
*
* Copies a GDate to a newly-allocated GDate. If the input was invalid
* (as determined by g_date_valid()), the invalid state will be copied
* as is into the new object.
*
* Returns: (transfer full): a newly-allocated #GDate initialized from @date
*
* Since: 2.56
*/
GDate *
g_date_copy (const GDate *date)
{
GDate *res;
g_return_val_if_fail (date != NULL, NULL);
if (g_date_valid (date))
res = g_date_new_julian (g_date_get_julian (date));
else
{
res = g_date_new ();
*res = *date;
}
return res;
}
/**
* g_date_valid:
* @date: a #GDate to check
*
* Returns %TRUE if the #GDate represents an existing day. The date must not
* contain garbage; it should have been initialized with g_date_clear()
* if it wasn't allocated by one of the g_date_new() variants.
*
* Returns: Whether the date is valid
*/
gboolean
g_date_valid (const GDate *d)
{
g_return_val_if_fail (d != NULL, FALSE);
return (d->julian || d->dmy);
}
static const guint8 days_in_months[2][13] =
{ /* error, jan feb mar apr may jun jul aug sep oct nov dec */
{ 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 } /* leap year */
};
static const guint16 days_in_year[2][14] =
{ /* 0, jan feb mar apr may jun jul aug sep oct nov dec */
{ 0, 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
{ 0, 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
};
/**
* g_date_valid_month:
* @month: month
*
* Returns %TRUE if the month value is valid. The 12 #GDateMonth
* enumeration values are the only valid months.
*
* Returns: %TRUE if the month is valid
*/
gboolean
g_date_valid_month (GDateMonth m)
{
return ( (m > G_DATE_BAD_MONTH) && (m < 13) );
}
/**
* g_date_valid_year:
* @year: year
*
* Returns %TRUE if the year is valid. Any year greater than 0 is valid,
* though there is a 16-bit limit to what #GDate will understand.
*
* Returns: %TRUE if the year is valid
*/
gboolean
g_date_valid_year (GDateYear y)
{
return ( y > G_DATE_BAD_YEAR );
}
/**
* g_date_valid_day:
* @day: day to check
*
* Returns %TRUE if the day of the month is valid (a day is valid if it's
* between 1 and 31 inclusive).
*
* Returns: %TRUE if the day is valid
*/
gboolean
g_date_valid_day (GDateDay d)
{
return ( (d > G_DATE_BAD_DAY) && (d < 32) );
}
/**
* g_date_valid_weekday:
* @weekday: weekday
*
* Returns %TRUE if the weekday is valid. The seven #GDateWeekday enumeration
* values are the only valid weekdays.
*
* Returns: %TRUE if the weekday is valid
*/
gboolean
g_date_valid_weekday (GDateWeekday w)
{
return ( (w > G_DATE_BAD_WEEKDAY) && (w < 8) );
}
/**
* g_date_valid_julian:
* @julian_date: Julian day to check
*
* Returns %TRUE if the Julian day is valid. Anything greater than zero
* is basically a valid Julian, though there is a 32-bit limit.
*
* Returns: %TRUE if the Julian day is valid
*/
gboolean
g_date_valid_julian (guint32 j)
{
return (j > G_DATE_BAD_JULIAN);
}
/**
* g_date_valid_dmy:
* @day: day
* @month: month
* @year: year
*
* Returns %TRUE if the day-month-year triplet forms a valid, existing day
* in the range of days #GDate understands (Year 1 or later, no more than
* a few thousand years in the future).
*
* Returns: %TRUE if the date is a valid one
*/
gboolean
g_date_valid_dmy (GDateDay d,
GDateMonth m,
GDateYear y)
{
/* No need to check the upper bound of @y, because #GDateYear is 16 bits wide,
* just like #GDate.year. */
return ( (m > G_DATE_BAD_MONTH) &&
(m < 13) &&
(d > G_DATE_BAD_DAY) &&
(y > G_DATE_BAD_YEAR) && /* must check before using g_date_is_leap_year */
(d <= (g_date_is_leap_year (y) ?
days_in_months[1][m] : days_in_months[0][m])) );
}
/* "Julian days" just means an absolute number of days, where Day 1 ==
* Jan 1, Year 1
*/
static void
g_date_update_julian (const GDate *const_d)
{
GDate *d = (GDate *) const_d;
GDateYear year;
gint idx;
g_return_if_fail (d != NULL);
g_return_if_fail (d->dmy != 0);
g_return_if_fail (!d->julian);
g_return_if_fail (g_date_valid_dmy (d->day, d->month, d->year));
/* What we actually do is: multiply years * 365 days in the year,
* add the number of years divided by 4, subtract the number of
* years divided by 100 and add the number of years divided by 400,
* which accounts for leap year stuff. Code from Steffen Beyer's
* DateCalc.
*/
year = d->year - 1; /* we know d->year > 0 since it's valid */
d->julian_days = year * 365U;
d->julian_days += (year >>= 2); /* divide by 4 and add */
d->julian_days -= (year /= 25); /* divides original # years by 100 */
d->julian_days += year >> 2; /* divides by 4, which divides original by 400 */
idx = g_date_is_leap_year (d->year) ? 1 : 0;
d->julian_days += days_in_year[idx][d->month] + d->day;
g_return_if_fail (g_date_valid_julian (d->julian_days));
d->julian = TRUE;
}
static void
g_date_update_dmy (const GDate *const_d)
{
GDate *d = (GDate *) const_d;
GDateYear y;
GDateMonth m;
GDateDay day;
guint32 A, B, C, D, E, M;
g_return_if_fail (d != NULL);
g_return_if_fail (d->julian);
g_return_if_fail (!d->dmy);
g_return_if_fail (g_date_valid_julian (d->julian_days));
/* Formula taken from the Calendar FAQ; the formula was for the
* Julian Period which starts on 1 January 4713 BC, so we add
* 1,721,425 to the number of days before doing the formula.
*
* I'm sure this can be simplified for our 1 January 1 AD period
* start, but I can't figure out how to unpack the formula.
*/
A = d->julian_days + 1721425 + 32045;
B = ( 4 *(A + 36524) )/ 146097 - 1;
C = A - (146097 * B)/4;
D = ( 4 * (C + 365) ) / 1461 - 1;
E = C - ((1461*D) / 4);
M = (5 * (E - 1) + 2)/153;
m = M + 3 - (12*(M/10));
day = E - (153*M + 2)/5;
y = 100 * B + D - 4800 + (M/10);
#ifdef G_ENABLE_DEBUG
if (!g_date_valid_dmy (day, m, y))
g_warning ("OOPS julian: %u computed dmy: %u %u %u",
d->julian_days, day, m, y);
#endif
d->month = m;
d->day = day;
d->year = y;
d->dmy = TRUE;
}
/**
* g_date_get_weekday:
* @date: a #GDate
*
* Returns the day of the week for a #GDate. The date must be valid.
*
* Returns: day of the week as a #GDateWeekday.
*/
GDateWeekday
g_date_get_weekday (const GDate *d)
{
g_return_val_if_fail (g_date_valid (d), G_DATE_BAD_WEEKDAY);
if (!d->julian)
g_date_update_julian (d);
g_return_val_if_fail (d->julian, G_DATE_BAD_WEEKDAY);
return ((d->julian_days - 1) % 7) + 1;
}
/**
* g_date_get_month:
* @date: a #GDate to get the month from
*
* Returns the month of the year. The date must be valid.
*
* Returns: month of the year as a #GDateMonth
*/
GDateMonth
g_date_get_month (const GDate *d)
{
g_return_val_if_fail (g_date_valid (d), G_DATE_BAD_MONTH);
if (!d->dmy)
g_date_update_dmy (d);
g_return_val_if_fail (d->dmy, G_DATE_BAD_MONTH);
return d->month;
}
/**
* g_date_get_year:
* @date: a #GDate
*
* Returns the year of a #GDate. The date must be valid.
*
* Returns: year in which the date falls
*/
GDateYear
g_date_get_year (const GDate *d)
{
g_return_val_if_fail (g_date_valid (d), G_DATE_BAD_YEAR);
if (!d->dmy)
g_date_update_dmy (d);
g_return_val_if_fail (d->dmy, G_DATE_BAD_YEAR);
return d->year;
}
/**
* g_date_get_day:
* @date: a #GDate to extract the day of the month from
*
* Returns the day of the month. The date must be valid.
*
* Returns: day of the month
*/
GDateDay
g_date_get_day (const GDate *d)
{
g_return_val_if_fail (g_date_valid (d), G_DATE_BAD_DAY);
if (!d->dmy)
g_date_update_dmy (d);
g_return_val_if_fail (d->dmy, G_DATE_BAD_DAY);
return d->day;
}
/**
* g_date_get_julian:
* @date: a #GDate to extract the Julian day from
*
* Returns the Julian day or "serial number" of the #GDate. The
* Julian day is simply the number of days since January 1, Year 1; i.e.,
* January 1, Year 1 is Julian day 1; January 2, Year 1 is Julian day 2,
* etc. The date must be valid.
*
* Returns: Julian day
*/
guint32
g_date_get_julian (const GDate *d)
{
g_return_val_if_fail (g_date_valid (d), G_DATE_BAD_JULIAN);
if (!d->julian)
g_date_update_julian (d);
g_return_val_if_fail (d->julian, G_DATE_BAD_JULIAN);
return d->julian_days;
}
/**
* g_date_get_day_of_year:
* @date: a #GDate to extract day of year from
*
* Returns the day of the year, where Jan 1 is the first day of the
* year. The date must be valid.
*
* Returns: day of the year
*/
guint
g_date_get_day_of_year (const GDate *d)
{
gint idx;
g_return_val_if_fail (g_date_valid (d), 0);
if (!d->dmy)
g_date_update_dmy (d);
g_return_val_if_fail (d->dmy, 0);
idx = g_date_is_leap_year (d->year) ? 1 : 0;
return (days_in_year[idx][d->month] + d->day);
}
/**
* g_date_get_monday_week_of_year:
* @date: a #GDate
*
* Returns the week of the year, where weeks are understood to start on
* Monday. If the date is before the first Monday of the year, return 0.
* The date must be valid.
*
* Returns: week of the year
*/
guint
g_date_get_monday_week_of_year (const GDate *d)
{
GDateWeekday wd;
guint day;
GDate first;
g_return_val_if_fail (g_date_valid (d), 0);
if (!d->dmy)
g_date_update_dmy (d);
g_return_val_if_fail (d->dmy, 0);
g_date_clear (&first, 1);
g_date_set_dmy (&first, 1, 1, d->year);
wd = g_date_get_weekday (&first) - 1; /* make Monday day 0 */
day = g_date_get_day_of_year (d) - 1;
return ((day + wd)/7U + (wd == 0 ? 1 : 0));
}
/**
* g_date_get_sunday_week_of_year:
* @date: a #GDate
*
* Returns the week of the year during which this date falls, if
* weeks are understood to begin on Sunday. The date must be valid.
* Can return 0 if the day is before the first Sunday of the year.
*
* Returns: week number
*/
guint
g_date_get_sunday_week_of_year (const GDate *d)
{
GDateWeekday wd;
guint day;
GDate first;
g_return_val_if_fail (g_date_valid (d), 0);
if (!d->dmy)
g_date_update_dmy (d);
g_return_val_if_fail (d->dmy, 0);
g_date_clear (&first, 1);
g_date_set_dmy (&first, 1, 1, d->year);
wd = g_date_get_weekday (&first);
if (wd == 7) wd = 0; /* make Sunday day 0 */
day = g_date_get_day_of_year (d) - 1;
return ((day + wd)/7U + (wd == 0 ? 1 : 0));
}
/**
* g_date_get_iso8601_week_of_year:
* @date: a valid #GDate
*
* Returns the week of the year, where weeks are interpreted according
* to ISO 8601.
*
* Returns: ISO 8601 week number of the year.
*
* Since: 2.6
**/
guint
g_date_get_iso8601_week_of_year (const GDate *d)
{
guint j, d4, L, d1, w;
g_return_val_if_fail (g_date_valid (d), 0);
if (!d->julian)
g_date_update_julian (d);
g_return_val_if_fail (d->julian, 0);
/* Formula taken from the Calendar FAQ; the formula was for the
* Julian Period which starts on 1 January 4713 BC, so we add
* 1,721,425 to the number of days before doing the formula.
*/
j = d->julian_days + 1721425;
d4 = (j + 31741 - (j % 7)) % 146097 % 36524 % 1461;
L = d4 / 1460;
d1 = ((d4 - L) % 365) + L;
w = d1 / 7 + 1;
return w;
}
/**
* g_date_days_between:
* @date1: the first date
* @date2: the second date
*
* Computes the number of days between two dates.
* If @date2 is prior to @date1, the returned value is negative.
* Both dates must be valid.
*
* Returns: the number of days between @date1 and @date2
*/
gint
g_date_days_between (const GDate *d1,
const GDate *d2)
{
g_return_val_if_fail (g_date_valid (d1), 0);
g_return_val_if_fail (g_date_valid (d2), 0);
return (gint)g_date_get_julian (d2) - (gint)g_date_get_julian (d1);
}
/**
* g_date_clear:
* @date: pointer to one or more dates to clear
* @n_dates: number of dates to clear
*
* Initializes one or more #GDate structs to a sane but invalid
* state. The cleared dates will not represent an existing date, but will
* not contain garbage. Useful to init a date declared on the stack.
* Validity can be tested with g_date_valid().
*/
void
g_date_clear (GDate *d, guint ndates)
{
g_return_if_fail (d != NULL);
g_return_if_fail (ndates != 0);
memset (d, 0x0, ndates*sizeof (GDate));
}
G_LOCK_DEFINE_STATIC (g_date_global);
/* These are for the parser, output to the user should use *
* g_date_strftime () - this creates more never-freed memory to annoy
* all those memory debugger users. :-)
*/
static gchar *long_month_names[13] =
{
NULL,
};
static gchar *long_month_names_alternative[13] =
{
NULL,
};
static gchar *short_month_names[13] =
{
NULL,
};
static gchar *short_month_names_alternative[13] =
{
NULL,
};
/* This tells us if we need to update the parse info */
static gchar *current_locale = NULL;
/* order of these in the current locale */
static GDateDMY dmy_order[3] =
{
G_DATE_DAY, G_DATE_MONTH, G_DATE_YEAR
};
/* Where to chop two-digit years: i.e., for the 1930 default, numbers
* 29 and below are counted as in the year 2000, numbers 30 and above
* are counted as in the year 1900.
*/
static const GDateYear twodigit_start_year = 1930;
/* It is impossible to enter a year between 1 AD and 99 AD with this
* in effect.
*/
static gboolean using_twodigit_years = FALSE;
/* Adjustment of locale era to AD, non-zero means using locale era
*/
static gint locale_era_adjust = 0;
struct _GDateParseTokens {
gint num_ints;
gint n[3];
guint month;
};
typedef struct _GDateParseTokens GDateParseTokens;
static inline gboolean
update_month_match (gsize *longest,
const gchar *haystack,
const gchar *needle)
{
gsize length;
if (needle == NULL)
return FALSE;
length = strlen (needle);
if (*longest >= length)
return FALSE;
if (strstr (haystack, needle) == NULL)
return FALSE;
*longest = length;
return TRUE;
}
#define NUM_LEN 10
/* HOLDS: g_date_global_lock */
static void
g_date_fill_parse_tokens (const gchar *str, GDateParseTokens *pt)
{
gchar num[4][NUM_LEN+1];
gint i;
const guchar *s;
/* We count 4, but store 3; so we can give an error
* if there are 4.
*/
num[0][0] = num[1][0] = num[2][0] = num[3][0] = '\0';
s = (const guchar *) str;
pt->num_ints = 0;
while (*s && pt->num_ints < 4)
{
i = 0;
while (*s && g_ascii_isdigit (*s) && i < NUM_LEN)
{
num[pt->num_ints][i] = *s;
++s;
++i;
}
if (i > 0)
{
num[pt->num_ints][i] = '\0';
++(pt->num_ints);
}
if (*s == '\0') break;
++s;
}
pt->n[0] = pt->num_ints > 0 ? atoi (num[0]) : 0;
pt->n[1] = pt->num_ints > 1 ? atoi (num[1]) : 0;
pt->n[2] = pt->num_ints > 2 ? atoi (num[2]) : 0;
pt->month = G_DATE_BAD_MONTH;
if (pt->num_ints < 3)
{
gsize longest = 0;
gchar *casefold;
gchar *normalized;
casefold = g_utf8_casefold (str, -1);
normalized = g_utf8_normalize (casefold, -1, G_NORMALIZE_ALL);
g_free (casefold);
for (i = 1; i < 13; ++i)
{
/* Here month names may be in a genitive case if the language
* grammatical rules require it.
* Examples of how January may look in some languages:
* Catalan: "de gener", Croatian: "siječnja", Polish: "stycznia",
* Upper Sorbian: "januara".
* Note that most of the languages can't or don't use the the
* genitive case here so they use nominative everywhere.
* For example, English always uses "January".
*/
if (update_month_match (&longest, normalized, long_month_names[i]))
pt->month = i;
/* Here month names will be in a nominative case.
* Examples of how January may look in some languages:
* Catalan: "gener", Croatian: "Siječanj", Polish: "styczeń",
* Upper Sorbian: "Januar".
*/
if (update_month_match (&longest, normalized, long_month_names_alternative[i]))
pt->month = i;
/* Differences between abbreviated nominative and abbreviated
* genitive month names are visible in very few languages but
* let's handle them.
*/
if (update_month_match (&longest, normalized, short_month_names[i]))
pt->month = i;
if (update_month_match (&longest, normalized, short_month_names_alternative[i]))
pt->month = i;
}
g_free (normalized);
}
}
/* HOLDS: g_date_global_lock */
static void
g_date_prepare_to_parse (const gchar *str,
GDateParseTokens *pt)
{
const gchar *locale = setlocale (LC_TIME, NULL);
gboolean recompute_localeinfo = FALSE;
GDate d;
g_return_if_fail (locale != NULL); /* should not happen */
g_date_clear (&d, 1); /* clear for scratch use */
if ( (current_locale == NULL) || (strcmp (locale, current_locale) != 0) )
recompute_localeinfo = TRUE; /* Uh, there used to be a reason for the temporary */
if (recompute_localeinfo)
{
int i = 1;
GDateParseTokens testpt;
gchar buf[128];
g_free (current_locale); /* still works if current_locale == NULL */
current_locale = g_strdup (locale);
short_month_names[0] = "Error";
long_month_names[0] = "Error";
while (i < 13)
{
gchar *casefold;
g_date_set_dmy (&d, 1, i, 1976);
g_return_if_fail (g_date_valid (&d));
g_date_strftime (buf, 127, "%b", &d);
casefold = g_utf8_casefold (buf, -1);
g_free (short_month_names[i]);
short_month_names[i] = g_utf8_normalize (casefold, -1, G_NORMALIZE_ALL);
g_free (casefold);
g_date_strftime (buf, 127, "%B", &d);
casefold = g_utf8_casefold (buf, -1);
g_free (long_month_names[i]);
long_month_names[i] = g_utf8_normalize (casefold, -1, G_NORMALIZE_ALL);
g_free (casefold);
g_date_strftime (buf, 127, "%Ob", &d);
casefold = g_utf8_casefold (buf, -1);
g_free (short_month_names_alternative[i]);
short_month_names_alternative[i] = g_utf8_normalize (casefold, -1, G_NORMALIZE_ALL);
g_free (casefold);
g_date_strftime (buf, 127, "%OB", &d);
casefold = g_utf8_casefold (buf, -1);
g_free (long_month_names_alternative[i]);
long_month_names_alternative[i] = g_utf8_normalize (casefold, -1, G_NORMALIZE_ALL);
g_free (casefold);
++i;
}
/* Determine DMY order */
/* had to pick a random day - don't change this, some strftimes
* are broken on some days, and this one is good so far. */
g_date_set_dmy (&d, 4, 7, 1976);
g_date_strftime (buf, 127, "%x", &d);
g_date_fill_parse_tokens (buf, &testpt);
using_twodigit_years = FALSE;
locale_era_adjust = 0;
dmy_order[0] = G_DATE_DAY;
dmy_order[1] = G_DATE_MONTH;
dmy_order[2] = G_DATE_YEAR;
i = 0;
while (i < testpt.num_ints)
{
switch (testpt.n[i])
{
case 7:
dmy_order[i] = G_DATE_MONTH;
break;
case 4:
dmy_order[i] = G_DATE_DAY;
break;
case 76:
using_twodigit_years = TRUE; /* FALL THRU */
case 1976:
dmy_order[i] = G_DATE_YEAR;
break;
default:
/* assume locale era */
locale_era_adjust = 1976 - testpt.n[i];
dmy_order[i] = G_DATE_YEAR;
break;
}
++i;
}
#if defined(G_ENABLE_DEBUG) && 0
DEBUG_MSG (("**GDate prepared a new set of locale-specific parse rules."));
i = 1;
while (i < 13)
{
DEBUG_MSG ((" %s %s", long_month_names[i], short_month_names[i]));
++i;
}
DEBUG_MSG (("Alternative month names:"));
i = 1;
while (i < 13)
{
DEBUG_MSG ((" %s %s", long_month_names_alternative[i], short_month_names_alternative[i]));
++i;
}
if (using_twodigit_years)
{
DEBUG_MSG (("**Using twodigit years with cutoff year: %u", twodigit_start_year));
}
{
gchar *strings[3];
i = 0;
while (i < 3)
{
switch (dmy_order[i])
{
case G_DATE_MONTH:
strings[i] = "Month";
break;
case G_DATE_YEAR:
strings[i] = "Year";
break;
case G_DATE_DAY:
strings[i] = "Day";
break;
default:
strings[i] = NULL;
break;
}
++i;
}
DEBUG_MSG (("**Order: %s, %s, %s", strings[0], strings[1], strings[2]));
DEBUG_MSG (("**Sample date in this locale: '%s'", buf));
}
#endif
}
g_date_fill_parse_tokens (str, pt);
}
/**
* g_date_set_parse:
* @date: a #GDate to fill in
* @str: string to parse
*
* Parses a user-inputted string @str, and try to figure out what date it
* represents, taking the [current locale][setlocale] into account. If the
* string is successfully parsed, the date will be valid after the call.
* Otherwise, it will be invalid. You should check using g_date_valid()
* to see whether the parsing succeeded.
*
* This function is not appropriate for file formats and the like; it
* isn't very precise, and its exact behavior varies with the locale.
* It's intended to be a heuristic routine that guesses what the user
* means by a given string (and it does work pretty well in that
* capacity).
*/
void
g_date_set_parse (GDate *d,
const gchar *str)
{
GDateParseTokens pt;
guint m = G_DATE_BAD_MONTH, day = G_DATE_BAD_DAY, y = G_DATE_BAD_YEAR;
g_return_if_fail (d != NULL);
/* set invalid */
g_date_clear (d, 1);
G_LOCK (g_date_global);
g_date_prepare_to_parse (str, &pt);
DEBUG_MSG (("Found %d ints, '%d' '%d' '%d' and written out month %d",
pt.num_ints, pt.n[0], pt.n[1], pt.n[2], pt.month));
if (pt.num_ints == 4)
{
G_UNLOCK (g_date_global);
return; /* presumably a typo; bail out. */
}
if (pt.num_ints > 1)
{
int i = 0;
int j = 0;
g_assert (pt.num_ints < 4); /* i.e., it is 2 or 3 */
while (i < pt.num_ints && j < 3)
{
switch (dmy_order[j])
{
case G_DATE_MONTH:
{
if (pt.num_ints == 2 && pt.month != G_DATE_BAD_MONTH)
{
m = pt.month;
++j; /* skip months, but don't skip this number */
continue;
}
else
m = pt.n[i];
}
break;
case G_DATE_DAY:
{
if (pt.num_ints == 2 && pt.month == G_DATE_BAD_MONTH)
{
day = 1;
++j; /* skip days, since we may have month/year */
continue;
}
day = pt.n[i];
}
break;
case G_DATE_YEAR:
{
y = pt.n[i];
if (locale_era_adjust != 0)
{
y += locale_era_adjust;
}
else if (using_twodigit_years && y < 100)
{
guint two = twodigit_start_year % 100;
guint century = (twodigit_start_year / 100) * 100;
if (y < two)
century += 100;
y += century;
}
}
break;
default:
break;
}
++i;
++j;
}
if (pt.num_ints == 3 && !g_date_valid_dmy (day, m, y))
{
/* Try YYYY MM DD */
y = pt.n[0];
m = pt.n[1];
day = pt.n[2];
if (using_twodigit_years && y < 100)
y = G_DATE_BAD_YEAR; /* avoids ambiguity */
}
else if (pt.num_ints == 2)
{
if (m == G_DATE_BAD_MONTH && pt.month != G_DATE_BAD_MONTH)
m = pt.month;
}
}
else if (pt.num_ints == 1)
{
if (pt.month != G_DATE_BAD_MONTH)
{
/* Month name and year? */
m = pt.month;
day = 1;
y = pt.n[0];
}
else
{
/* Try yyyymmdd and yymmdd */
m = (pt.n[0]/100) % 100;
day = pt.n[0] % 100;
y = pt.n[0]/10000;
/* FIXME move this into a separate function */
if (using_twodigit_years && y < 100)
{
guint two = twodigit_start_year % 100;
guint century = (twodigit_start_year / 100) * 100;
if (y < two)
century += 100;
y += century;
}
}
}
/* See if we got anything valid out of all this. */
/* y < 8000 is to catch 19998 style typos; the library is OK up to 65535 or so */
if (y < 8000 && g_date_valid_dmy (day, m, y))
{
d->month = m;
d->day = day;
d->year = y;
d->dmy = TRUE;
}
#ifdef G_ENABLE_DEBUG
else
{
DEBUG_MSG (("Rejected DMY %u %u %u", day, m, y));
}
#endif
G_UNLOCK (g_date_global);
}
/**
* g_date_set_time_t:
* @date: a #GDate
* @timet: time_t value to set
*
* Sets the value of a date to the date corresponding to a time
* specified as a time_t. The time to date conversion is done using
* the user's current timezone.
*
* To set the value of a date to the current day, you could write:
* |[<!-- language="C" -->
* time_t now = time (NULL);
* if (now == (time_t) -1)
* // handle the error
* g_date_set_time_t (date, now);
* ]|
*
* Since: 2.10
*/
void
g_date_set_time_t (GDate *date,
time_t timet)
{
struct tm tm;
g_return_if_fail (date != NULL);
#ifdef HAVE_LOCALTIME_R
localtime_r (&timet, &tm);
#else
{
struct tm *ptm = localtime (&timet);
if (ptm == NULL)
{
/* Happens at least in Microsoft's C library if you pass a
* negative time_t. Use 2000-01-01 as default date.
*/
#ifndef G_DISABLE_CHECKS
g_return_if_fail_warning (G_LOG_DOMAIN, "g_date_set_time", "ptm != NULL");
#endif
tm.tm_mon = 0;
tm.tm_mday = 1;
tm.tm_year = 100;
}
else
memcpy ((void *) &tm, (void *) ptm, sizeof(struct tm));
}
#endif
date->julian = FALSE;
date->month = tm.tm_mon + 1;
date->day = tm.tm_mday;
date->year = tm.tm_year + 1900;
g_return_if_fail (g_date_valid_dmy (date->day, date->month, date->year));
date->dmy = TRUE;
}
/**
* g_date_set_time:
* @date: a #GDate.
* @time_: #GTime value to set.
*
* Sets the value of a date from a #GTime value.
* The time to date conversion is done using the user's current timezone.
*
* Deprecated: 2.10: Use g_date_set_time_t() instead.
*/
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
void
g_date_set_time (GDate *date,
GTime time_)
{
g_date_set_time_t (date, (time_t) time_);
}
G_GNUC_END_IGNORE_DEPRECATIONS
/**
* g_date_set_time_val:
* @date: a #GDate
* @timeval: #GTimeVal value to set
*
* Sets the value of a date from a #GTimeVal value. Note that the
* @tv_usec member is ignored, because #GDate can't make use of the
* additional precision.
*
* The time to date conversion is done using the user's current timezone.
*
* Since: 2.10
* Deprecated: 2.62: #GTimeVal is not year-2038-safe. Use g_date_set_time_t()
* instead.
*/
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
void
g_date_set_time_val (GDate *date,
GTimeVal *timeval)
{
g_date_set_time_t (date, (time_t) timeval->tv_sec);
}
G_GNUC_END_IGNORE_DEPRECATIONS
/**
* g_date_set_month:
* @date: a #GDate
* @month: month to set
*
* Sets the month of the year for a #GDate. If the resulting
* day-month-year triplet is invalid, the date will be invalid.
*/
void
g_date_set_month (GDate *d,
GDateMonth m)
{
g_return_if_fail (d != NULL);
g_return_if_fail (g_date_valid_month (m));
if (d->julian && !d->dmy) g_date_update_dmy(d);
d->julian = FALSE;
d->month = m;
if (g_date_valid_dmy (d->day, d->month, d->year))
d->dmy = TRUE;
else
d->dmy = FALSE;
}
/**
* g_date_set_day:
* @date: a #GDate
* @day: day to set
*
* Sets the day of the month for a #GDate. If the resulting
* day-month-year triplet is invalid, the date will be invalid.
*/
void
g_date_set_day (GDate *d,
GDateDay day)
{
g_return_if_fail (d != NULL);
g_return_if_fail (g_date_valid_day (day));
if (d->julian && !d->dmy) g_date_update_dmy(d);
d->julian = FALSE;
d->day = day;
if (g_date_valid_dmy (d->day, d->month, d->year))
d->dmy = TRUE;
else
d->dmy = FALSE;
}
/**
* g_date_set_year:
* @date: a #GDate
* @year: year to set
*
* Sets the year for a #GDate. If the resulting day-month-year
* triplet is invalid, the date will be invalid.
*/
void
g_date_set_year (GDate *d,
GDateYear y)
{
g_return_if_fail (d != NULL);
g_return_if_fail (g_date_valid_year (y));
if (d->julian && !d->dmy) g_date_update_dmy(d);
d->julian = FALSE;
d->year = y;
if (g_date_valid_dmy (d->day, d->month, d->year))
d->dmy = TRUE;
else
d->dmy = FALSE;
}
/**
* g_date_set_dmy:
* @date: a #GDate
* @day: day
* @month: month
* @y: year
*
* Sets the value of a #GDate from a day, month, and year.
* The day-month-year triplet must be valid; if you aren't
* sure it is, call g_date_valid_dmy() to check before you
* set it.
*/
void
g_date_set_dmy (GDate *d,
GDateDay day,
GDateMonth m,
GDateYear y)
{
g_return_if_fail (d != NULL);
g_return_if_fail (g_date_valid_dmy (day, m, y));
d->julian = FALSE;
d->month = m;
d->day = day;
d->year = y;
d->dmy = TRUE;
}
/**
* g_date_set_julian:
* @date: a #GDate
* @julian_date: Julian day number (days since January 1, Year 1)
*
* Sets the value of a #GDate from a Julian day number.
*/
void
g_date_set_julian (GDate *d,
guint32 j)
{
g_return_if_fail (d != NULL);
g_return_if_fail (g_date_valid_julian (j));
d->julian_days = j;
d->julian = TRUE;
d->dmy = FALSE;
}
/**
* g_date_is_first_of_month:
* @date: a #GDate to check
*
* Returns %TRUE if the date is on the first of a month.
* The date must be valid.
*
* Returns: %TRUE if the date is the first of the month
*/
gboolean
g_date_is_first_of_month (const GDate *d)
{
g_return_val_if_fail (g_date_valid (d), FALSE);
if (!d->dmy)
g_date_update_dmy (d);
g_return_val_if_fail (d->dmy, FALSE);
if (d->day == 1) return TRUE;
else return FALSE;
}
/**
* g_date_is_last_of_month:
* @date: a #GDate to check
*
* Returns %TRUE if the date is the last day of the month.
* The date must be valid.
*
* Returns: %TRUE if the date is the last day of the month
*/
gboolean
g_date_is_last_of_month (const GDate *d)
{
gint idx;
g_return_val_if_fail (g_date_valid (d), FALSE);
if (!d->dmy)
g_date_update_dmy (d);
g_return_val_if_fail (d->dmy, FALSE);
idx = g_date_is_leap_year (d->year) ? 1 : 0;
if (d->day == days_in_months[idx][d->month]) return TRUE;
else return FALSE;
}
/**
* g_date_add_days:
* @date: a #GDate to increment
* @n_days: number of days to move the date forward
*
* Increments a date some number of days.
* To move forward by weeks, add weeks*7 days.
* The date must be valid.
*/
void
g_date_add_days (GDate *d,
guint ndays)
{
g_return_if_fail (g_date_valid (d));
if (!d->julian)
g_date_update_julian (d);
g_return_if_fail (d->julian);
g_return_if_fail (ndays <= G_MAXUINT32 - d->julian_days);
d->julian_days += ndays;
d->dmy = FALSE;
}
/**
* g_date_subtract_days:
* @date: a #GDate to decrement
* @n_days: number of days to move
*
* Moves a date some number of days into the past.
* To move by weeks, just move by weeks*7 days.
* The date must be valid.
*/
void
g_date_subtract_days (GDate *d,
guint ndays)
{
g_return_if_fail (g_date_valid (d));
if (!d->julian)
g_date_update_julian (d);
g_return_if_fail (d->julian);
g_return_if_fail (d->julian_days > ndays);
d->julian_days -= ndays;
d->dmy = FALSE;
}
/**
* g_date_add_months:
* @date: a #GDate to increment
* @n_months: number of months to move forward
*
* Increments a date by some number of months.
* If the day of the month is greater than 28,
* this routine may change the day of the month
* (because the destination month may not have
* the current day in it). The date must be valid.
*/
void
g_date_add_months (GDate *d,
guint nmonths)
{
guint years, months;
gint idx;
g_return_if_fail (g_date_valid (d));
if (!d->dmy)
g_date_update_dmy (d);
g_return_if_fail (d->dmy != 0);
g_return_if_fail (nmonths <= G_MAXUINT - (d->month - 1));
nmonths += d->month - 1;
years = nmonths/12;
months = nmonths%12;
g_return_if_fail (years <= (guint) (G_MAXUINT16 - d->year));
d->month = months + 1;
d->year += years;
idx = g_date_is_leap_year (d->year) ? 1 : 0;
if (d->day > days_in_months[idx][d->month])
d->day = days_in_months[idx][d->month];
d->julian = FALSE;
g_return_if_fail (g_date_valid (d));
}
/**
* g_date_subtract_months:
* @date: a #GDate to decrement
* @n_months: number of months to move
*
* Moves a date some number of months into the past.
* If the current day of the month doesn't exist in
* the destination month, the day of the month
* may change. The date must be valid.
*/
void
g_date_subtract_months (GDate *d,
guint nmonths)
{
guint years, months;
gint idx;
g_return_if_fail (g_date_valid (d));
if (!d->dmy)
g_date_update_dmy (d);
g_return_if_fail (d->dmy != 0);
years = nmonths/12;
months = nmonths%12;
g_return_if_fail (d->year > years);
d->year -= years;
if (d->month > months) d->month -= months;
else
{
months -= d->month;
d->month = 12 - months;
d->year -= 1;
}
idx = g_date_is_leap_year (d->year) ? 1 : 0;
if (d->day > days_in_months[idx][d->month])
d->day = days_in_months[idx][d->month];
d->julian = FALSE;
g_return_if_fail (g_date_valid (d));
}
/**
* g_date_add_years:
* @date: a #GDate to increment
* @n_years: number of years to move forward
*
* Increments a date by some number of years.
* If the date is February 29, and the destination
* year is not a leap year, the date will be changed
* to February 28. The date must be valid.
*/
void
g_date_add_years (GDate *d,
guint nyears)
{
g_return_if_fail (g_date_valid (d));
if (!d->dmy)
g_date_update_dmy (d);
g_return_if_fail (d->dmy != 0);
g_return_if_fail (nyears <= (guint) (G_MAXUINT16 - d->year));
d->year += nyears;
if (d->month == 2 && d->day == 29)
{
if (!g_date_is_leap_year (d->year))
d->day = 28;
}
d->julian = FALSE;
}
/**
* g_date_subtract_years:
* @date: a #GDate to decrement
* @n_years: number of years to move
*
* Moves a date some number of years into the past.
* If the current day doesn't exist in the destination
* year (i.e. it's February 29 and you move to a non-leap-year)
* then the day is changed to February 29. The date
* must be valid.
*/
void
g_date_subtract_years (GDate *d,
guint nyears)
{
g_return_if_fail (g_date_valid (d));
if (!d->dmy)
g_date_update_dmy (d);
g_return_if_fail (d->dmy != 0);
g_return_if_fail (d->year > nyears);
d->year -= nyears;
if (d->month == 2 && d->day == 29)
{
if (!g_date_is_leap_year (d->year))
d->day = 28;
}
d->julian = FALSE;
}
/**
* g_date_is_leap_year:
* @year: year to check
*
* Returns %TRUE if the year is a leap year.
*
* For the purposes of this function, leap year is every year
* divisible by 4 unless that year is divisible by 100. If it
* is divisible by 100 it would be a leap year only if that year
* is also divisible by 400.
*
* Returns: %TRUE if the year is a leap year
*/
gboolean
g_date_is_leap_year (GDateYear year)
{
g_return_val_if_fail (g_date_valid_year (year), FALSE);
return ( (((year % 4) == 0) && ((year % 100) != 0)) ||
(year % 400) == 0 );
}
/**
* g_date_get_days_in_month:
* @month: month
* @year: year
*
* Returns the number of days in a month, taking leap
* years into account.
*
* Returns: number of days in @month during the @year
*/
guint8
g_date_get_days_in_month (GDateMonth month,
GDateYear year)
{
gint idx;
g_return_val_if_fail (g_date_valid_year (year), 0);
g_return_val_if_fail (g_date_valid_month (month), 0);
idx = g_date_is_leap_year (year) ? 1 : 0;
return days_in_months[idx][month];
}
/**
* g_date_get_monday_weeks_in_year:
* @year: a year
*
* Returns the number of weeks in the year, where weeks
* are taken to start on Monday. Will be 52 or 53. The
* date must be valid. (Years always have 52 7-day periods,
* plus 1 or 2 extra days depending on whether it's a leap
* year. This function is basically telling you how many
* Mondays are in the year, i.e. there are 53 Mondays if
* one of the extra days happens to be a Monday.)
*
* Returns: number of Mondays in the year
*/
guint8
g_date_get_monday_weeks_in_year (GDateYear year)
{
GDate d;
g_return_val_if_fail (g_date_valid_year (year), 0);
g_date_clear (&d, 1);
g_date_set_dmy (&d, 1, 1, year);
if (g_date_get_weekday (&d) == G_DATE_MONDAY) return 53;
g_date_set_dmy (&d, 31, 12, year);
if (g_date_get_weekday (&d) == G_DATE_MONDAY) return 53;
if (g_date_is_leap_year (year))
{
g_date_set_dmy (&d, 2, 1, year);
if (g_date_get_weekday (&d) == G_DATE_MONDAY) return 53;
g_date_set_dmy (&d, 30, 12, year);
if (g_date_get_weekday (&d) == G_DATE_MONDAY) return 53;
}
return 52;
}
/**
* g_date_get_sunday_weeks_in_year:
* @year: year to count weeks in
*
* Returns the number of weeks in the year, where weeks
* are taken to start on Sunday. Will be 52 or 53. The
* date must be valid. (Years always have 52 7-day periods,
* plus 1 or 2 extra days depending on whether it's a leap
* year. This function is basically telling you how many
* Sundays are in the year, i.e. there are 53 Sundays if
* one of the extra days happens to be a Sunday.)
*
* Returns: the number of weeks in @year
*/
guint8
g_date_get_sunday_weeks_in_year (GDateYear year)
{
GDate d;
g_return_val_if_fail (g_date_valid_year (year), 0);
g_date_clear (&d, 1);
g_date_set_dmy (&d, 1, 1, year);
if (g_date_get_weekday (&d) == G_DATE_SUNDAY) return 53;
g_date_set_dmy (&d, 31, 12, year);
if (g_date_get_weekday (&d) == G_DATE_SUNDAY) return 53;
if (g_date_is_leap_year (year))
{
g_date_set_dmy (&d, 2, 1, year);
if (g_date_get_weekday (&d) == G_DATE_SUNDAY) return 53;
g_date_set_dmy (&d, 30, 12, year);
if (g_date_get_weekday (&d) == G_DATE_SUNDAY) return 53;
}
return 52;
}
/**
* g_date_compare:
* @lhs: first date to compare
* @rhs: second date to compare
*
* qsort()-style comparison function for dates.
* Both dates must be valid.
*
* Returns: 0 for equal, less than zero if @lhs is less than @rhs,
* greater than zero if @lhs is greater than @rhs
*/
gint
g_date_compare (const GDate *lhs,
const GDate *rhs)
{
g_return_val_if_fail (lhs != NULL, 0);
g_return_val_if_fail (rhs != NULL, 0);
g_return_val_if_fail (g_date_valid (lhs), 0);
g_return_val_if_fail (g_date_valid (rhs), 0);
/* Remember the self-comparison case! I think it works right now. */
while (TRUE)
{
if (lhs->julian && rhs->julian)
{
if (lhs->julian_days < rhs->julian_days) return -1;
else if (lhs->julian_days > rhs->julian_days) return 1;
else return 0;
}
else if (lhs->dmy && rhs->dmy)
{
if (lhs->year < rhs->year) return -1;
else if (lhs->year > rhs->year) return 1;
else
{
if (lhs->month < rhs->month) return -1;
else if (lhs->month > rhs->month) return 1;
else
{
if (lhs->day < rhs->day) return -1;
else if (lhs->day > rhs->day) return 1;
else return 0;
}
}
}
else
{
if (!lhs->julian) g_date_update_julian (lhs);
if (!rhs->julian) g_date_update_julian (rhs);
g_return_val_if_fail (lhs->julian, 0);
g_return_val_if_fail (rhs->julian, 0);
}
}
return 0; /* warnings */
}
/**
* g_date_to_struct_tm:
* @date: a #GDate to set the struct tm from
* @tm: (not nullable): struct tm to fill
*
* Fills in the date-related bits of a struct tm using the @date value.
* Initializes the non-date parts with something sane but meaningless.
*/
void
g_date_to_struct_tm (const GDate *d,
struct tm *tm)
{
GDateWeekday day;
g_return_if_fail (g_date_valid (d));
g_return_if_fail (tm != NULL);
if (!d->dmy)
g_date_update_dmy (d);
g_return_if_fail (d->dmy != 0);
/* zero all the irrelevant fields to be sure they're valid */
/* On Linux and maybe other systems, there are weird non-POSIX
* fields on the end of struct tm that choke strftime if they
* contain garbage. So we need to 0 the entire struct, not just the
* fields we know to exist.
*/
memset (tm, 0x0, sizeof (struct tm));
tm->tm_mday = d->day;
tm->tm_mon = d->month - 1; /* 0-11 goes in tm */
tm->tm_year = ((int)d->year) - 1900; /* X/Open says tm_year can be negative */
day = g_date_get_weekday (d);
if (day == 7) day = 0; /* struct tm wants days since Sunday, so Sunday is 0 */
tm->tm_wday = (int)day;
tm->tm_yday = g_date_get_day_of_year (d) - 1; /* 0 to 365 */
tm->tm_isdst = -1; /* -1 means "information not available" */
}
/**
* g_date_clamp:
* @date: a #GDate to clamp
* @min_date: minimum accepted value for @date
* @max_date: maximum accepted value for @date
*
* If @date is prior to @min_date, sets @date equal to @min_date.
* If @date falls after @max_date, sets @date equal to @max_date.
* Otherwise, @date is unchanged.
* Either of @min_date and @max_date may be %NULL.
* All non-%NULL dates must be valid.
*/
void
g_date_clamp (GDate *date,
const GDate *min_date,
const GDate *max_date)
{
g_return_if_fail (g_date_valid (date));
if (min_date != NULL)
g_return_if_fail (g_date_valid (min_date));
if (max_date != NULL)
g_return_if_fail (g_date_valid (max_date));
if (min_date != NULL && max_date != NULL)
g_return_if_fail (g_date_compare (min_date, max_date) <= 0);
if (min_date && g_date_compare (date, min_date) < 0)
*date = *min_date;
if (max_date && g_date_compare (max_date, date) < 0)
*date = *max_date;
}
/**
* g_date_order:
* @date1: the first date
* @date2: the second date
*
* Checks if @date1 is less than or equal to @date2,
* and swap the values if this is not the case.
*/
void
g_date_order (GDate *date1,
GDate *date2)
{
g_return_if_fail (g_date_valid (date1));
g_return_if_fail (g_date_valid (date2));
if (g_date_compare (date1, date2) > 0)
{
GDate tmp = *date1;
*date1 = *date2;
*date2 = tmp;
}
}
#ifdef G_OS_WIN32
static void
append_month_name (GArray *result,
LCID lcid,
SYSTEMTIME *systemtime,
gboolean abbreviated,
gboolean alternative)
{
int n;
WORD base;
LPCWSTR lpFormat;
if (alternative)
{
base = abbreviated ? LOCALE_SABBREVMONTHNAME1 : LOCALE_SMONTHNAME1;
n = GetLocaleInfoW (lcid, base + systemtime->wMonth - 1, NULL, 0);
g_array_set_size (result, result->len + n);
GetLocaleInfoW (lcid, base + systemtime->wMonth - 1,
((wchar_t *) result->data) + result->len - n, n);
g_array_set_size (result, result->len - 1);
}
else
{
/* According to MSDN, this is the correct method to obtain
* the form of the month name used when formatting a full
* date; it must be a genitive case in some languages.
*/
lpFormat = abbreviated ? L"ddMMM" : L"ddMMMM";
n = GetDateFormatW (lcid, 0, systemtime, lpFormat, NULL, 0);
g_array_set_size (result, result->len + n);
GetDateFormatW (lcid, 0, systemtime, lpFormat,
((wchar_t *) result->data) + result->len - n, n);
/* We have obtained a day number as two digits and the month name.
* Now let's get rid of those two digits: overwrite them with the
* month name.
*/
memmove (((wchar_t *) result->data) + result->len - n,
((wchar_t *) result->data) + result->len - n + 2,
(n - 2) * sizeof (wchar_t));
g_array_set_size (result, result->len - 3);
}
}
static gsize
win32_strftime_helper (const GDate *d,
const gchar *format,
const struct tm *tm,
gchar *s,
gsize slen)
{
SYSTEMTIME systemtime;
TIME_ZONE_INFORMATION tzinfo;
LCID lcid;
int n, k;
GArray *result;
const gchar *p;
gunichar c, modifier;
const wchar_t digits[] = L"0123456789";
gchar *convbuf;
glong convlen = 0;
gsize retval;
systemtime.wYear = tm->tm_year + 1900;
systemtime.wMonth = tm->tm_mon + 1;
systemtime.wDayOfWeek = tm->tm_wday;
systemtime.wDay = tm->tm_mday;
systemtime.wHour = tm->tm_hour;
systemtime.wMinute = tm->tm_min;
systemtime.wSecond = tm->tm_sec;
systemtime.wMilliseconds = 0;
lcid = GetThreadLocale ();
result = g_array_sized_new (FALSE, FALSE, sizeof (wchar_t), MAX (128, strlen (format) * 2));
p = format;
while (*p)
{
c = g_utf8_get_char (p);
if (c == '%')
{
p = g_utf8_next_char (p);
if (!*p)
{
s[0] = '\0';
g_array_free (result, TRUE);
return 0;
}
modifier = '\0';
c = g_utf8_get_char (p);
if (c == 'E' || c == 'O')
{
/* "%OB", "%Ob", and "%Oh" are supported, ignore other modified
* conversion specifiers for now.
*/
modifier = c;
p = g_utf8_next_char (p);
if (!*p)
{
s[0] = '\0';
g_array_free (result, TRUE);
return 0;
}
c = g_utf8_get_char (p);
}
switch (c)
{
case 'a':
if (systemtime.wDayOfWeek == 0)
k = 6;
else
k = systemtime.wDayOfWeek - 1;
n = GetLocaleInfoW (lcid, LOCALE_SABBREVDAYNAME1+k, NULL, 0);
g_array_set_size (result, result->len + n);
GetLocaleInfoW (lcid, LOCALE_SABBREVDAYNAME1+k, ((wchar_t *) result->data) + result->len - n, n);
g_array_set_size (result, result->len - 1);
break;
case 'A':
if (systemtime.wDayOfWeek == 0)
k = 6;
else
k = systemtime.wDayOfWeek - 1;
n = GetLocaleInfoW (lcid, LOCALE_SDAYNAME1+k, NULL, 0);
g_array_set_size (result, result->len + n);
GetLocaleInfoW (lcid, LOCALE_SDAYNAME1+k, ((wchar_t *) result->data) + result->len - n, n);
g_array_set_size (result, result->len - 1);
break;
case 'b':
case 'h':
append_month_name (result, lcid, &systemtime, TRUE,
modifier == 'O');
break;
case 'B':
append_month_name (result, lcid, &systemtime, FALSE,
modifier == 'O');
break;
case 'c':
n = GetDateFormatW (lcid, 0, &systemtime, NULL, NULL, 0);
if (n > 0)
{
g_array_set_size (result, result->len + n);
GetDateFormatW (lcid, 0, &systemtime, NULL, ((wchar_t *) result->data) + result->len - n, n);
g_array_set_size (result, result->len - 1);
}
g_array_append_vals (result, L" ", 1);
n = GetTimeFormatW (lcid, 0, &systemtime, NULL, NULL, 0);
if (n > 0)
{
g_array_set_size (result, result->len + n);
GetTimeFormatW (lcid, 0, &systemtime, NULL, ((wchar_t *) result->data) + result->len - n, n);
g_array_set_size (result, result->len - 1);
}
break;
case 'C':
g_array_append_vals (result, digits + systemtime.wYear/1000, 1);
g_array_append_vals (result, digits + (systemtime.wYear/1000)%10, 1);
break;
case 'd':
g_array_append_vals (result, digits + systemtime.wDay/10, 1);
g_array_append_vals (result, digits + systemtime.wDay%10, 1);
break;
case 'D':
g_array_append_vals (result, digits + systemtime.wMonth/10, 1);
g_array_append_vals (result, digits + systemtime.wMonth%10, 1);
g_array_append_vals (result, L"/", 1);
g_array_append_vals (result, digits + systemtime.wDay/10, 1);
g_array_append_vals (result, digits + systemtime.wDay%10, 1);
g_array_append_vals (result, L"/", 1);
g_array_append_vals (result, digits + (systemtime.wYear/10)%10, 1);
g_array_append_vals (result, digits + systemtime.wYear%10, 1);
break;
case 'e':
if (systemtime.wDay >= 10)
g_array_append_vals (result, digits + systemtime.wDay/10, 1);
else
g_array_append_vals (result, L" ", 1);
g_array_append_vals (result, digits + systemtime.wDay%10, 1);
break;
/* A GDate has no time fields, so for now we can
* hardcode all time conversions into zeros (or 12 for
* %I). The alternative code snippets in the #else
* branches are here ready to be taken into use when
* needed by a g_strftime() or g_date_and_time_format()
* or whatever.
*/
case 'H':
#if 1
g_array_append_vals (result, L"00", 2);
#else
g_array_append_vals (result, digits + systemtime.wHour/10, 1);
g_array_append_vals (result, digits + systemtime.wHour%10, 1);
#endif
break;
case 'I':
#if 1
g_array_append_vals (result, L"12", 2);
#else
if (systemtime.wHour == 0)
g_array_append_vals (result, L"12", 2);
else
{
g_array_append_vals (result, digits + (systemtime.wHour%12)/10, 1);
g_array_append_vals (result, digits + (systemtime.wHour%12)%10, 1);
}
#endif
break;
case 'j':
g_array_append_vals (result, digits + (tm->tm_yday+1)/100, 1);
g_array_append_vals (result, digits + ((tm->tm_yday+1)/10)%10, 1);
g_array_append_vals (result, digits + (tm->tm_yday+1)%10, 1);
break;
case 'm':
g_array_append_vals (result, digits + systemtime.wMonth/10, 1);
g_array_append_vals (result, digits + systemtime.wMonth%10, 1);
break;
case 'M':
#if 1
g_array_append_vals (result, L"00", 2);
#else
g_array_append_vals (result, digits + systemtime.wMinute/10, 1);
g_array_append_vals (result, digits + systemtime.wMinute%10, 1);
#endif
break;
case 'n':
g_array_append_vals (result, L"\n", 1);
break;
case 'p':
n = GetTimeFormatW (lcid, 0, &systemtime, L"tt", NULL, 0);
if (n > 0)
{
g_array_set_size (result, result->len + n);
GetTimeFormatW (lcid, 0, &systemtime, L"tt", ((wchar_t *) result->data) + result->len - n, n);
g_array_set_size (result, result->len - 1);
}
break;
case 'r':
/* This is a rather odd format. Hard to say what to do.
* Let's always use the POSIX %I:%M:%S %p
*/
#if 1
g_array_append_vals (result, L"12:00:00", 8);
#else
if (systemtime.wHour == 0)
g_array_append_vals (result, L"12", 2);
else
{
g_array_append_vals (result, digits + (systemtime.wHour%12)/10, 1);
g_array_append_vals (result, digits + (systemtime.wHour%12)%10, 1);
}
g_array_append_vals (result, L":", 1);
g_array_append_vals (result, digits + systemtime.wMinute/10, 1);
g_array_append_vals (result, digits + systemtime.wMinute%10, 1);
g_array_append_vals (result, L":", 1);
g_array_append_vals (result, digits + systemtime.wSecond/10, 1);
g_array_append_vals (result, digits + systemtime.wSecond%10, 1);
g_array_append_vals (result, L" ", 1);
#endif
n = GetTimeFormatW (lcid, 0, &systemtime, L"tt", NULL, 0);
if (n > 0)
{
g_array_set_size (result, result->len + n);
GetTimeFormatW (lcid, 0, &systemtime, L"tt", ((wchar_t *) result->data) + result->len - n, n);
g_array_set_size (result, result->len - 1);
}
break;
case 'R':
#if 1
g_array_append_vals (result, L"00:00", 5);
#else
g_array_append_vals (result, digits + systemtime.wHour/10, 1);
g_array_append_vals (result, digits + systemtime.wHour%10, 1);
g_array_append_vals (result, L":", 1);
g_array_append_vals (result, digits + systemtime.wMinute/10, 1);
g_array_append_vals (result, digits + systemtime.wMinute%10, 1);
#endif
break;
case 'S':
#if 1
g_array_append_vals (result, L"00", 2);
#else
g_array_append_vals (result, digits + systemtime.wSecond/10, 1);
g_array_append_vals (result, digits + systemtime.wSecond%10, 1);
#endif
break;
case 't':
g_array_append_vals (result, L"\t", 1);
break;
case 'T':
#if 1
g_array_append_vals (result, L"00:00:00", 8);
#else
g_array_append_vals (result, digits + systemtime.wHour/10, 1);
g_array_append_vals (result, digits + systemtime.wHour%10, 1);
g_array_append_vals (result, L":", 1);
g_array_append_vals (result, digits + systemtime.wMinute/10, 1);
g_array_append_vals (result, digits + systemtime.wMinute%10, 1);
g_array_append_vals (result, L":", 1);
g_array_append_vals (result, digits + systemtime.wSecond/10, 1);
g_array_append_vals (result, digits + systemtime.wSecond%10, 1);
#endif
break;
case 'u':
if (systemtime.wDayOfWeek == 0)
g_array_append_vals (result, L"7", 1);
else
g_array_append_vals (result, digits + systemtime.wDayOfWeek, 1);
break;
case 'U':
n = g_date_get_sunday_week_of_year (d);
g_array_append_vals (result, digits + n/10, 1);
g_array_append_vals (result, digits + n%10, 1);
break;
case 'V':
n = g_date_get_iso8601_week_of_year (d);
g_array_append_vals (result, digits + n/10, 1);
g_array_append_vals (result, digits + n%10, 1);
break;
case 'w':
g_array_append_vals (result, digits + systemtime.wDayOfWeek, 1);
break;
case 'W':
n = g_date_get_monday_week_of_year (d);
g_array_append_vals (result, digits + n/10, 1);
g_array_append_vals (result, digits + n%10, 1);
break;
case 'x':
n = GetDateFormatW (lcid, 0, &systemtime, NULL, NULL, 0);
if (n > 0)
{
g_array_set_size (result, result->len + n);
GetDateFormatW (lcid, 0, &systemtime, NULL, ((wchar_t *) result->data) + result->len - n, n);
g_array_set_size (result, result->len - 1);
}
break;
case 'X':
n = GetTimeFormatW (lcid, 0, &systemtime, NULL, NULL, 0);
if (n > 0)
{
g_array_set_size (result, result->len + n);
GetTimeFormatW (lcid, 0, &systemtime, NULL, ((wchar_t *) result->data) + result->len - n, n);
g_array_set_size (result, result->len - 1);
}
break;
case 'y':
g_array_append_vals (result, digits + (systemtime.wYear/10)%10, 1);
g_array_append_vals (result, digits + systemtime.wYear%10, 1);
break;
case 'Y':
g_array_append_vals (result, digits + systemtime.wYear/1000, 1);
g_array_append_vals (result, digits + (systemtime.wYear/100)%10, 1);
g_array_append_vals (result, digits + (systemtime.wYear/10)%10, 1);
g_array_append_vals (result, digits + systemtime.wYear%10, 1);
break;
case 'Z':
n = GetTimeZoneInformation (&tzinfo);
if (n == TIME_ZONE_ID_UNKNOWN)
;
else if (n == TIME_ZONE_ID_STANDARD)
g_array_append_vals (result, tzinfo.StandardName, wcslen (tzinfo.StandardName));
else if (n == TIME_ZONE_ID_DAYLIGHT)
g_array_append_vals (result, tzinfo.DaylightName, wcslen (tzinfo.DaylightName));
break;
case '%':
g_array_append_vals (result, L"%", 1);
break;
}
}
else if (c <= 0xFFFF)
{
wchar_t wc = c;
g_array_append_vals (result, &wc, 1);
}
else
{
glong nwc;
wchar_t *ws;
ws = g_ucs4_to_utf16 (&c, 1, NULL, &nwc, NULL);
g_array_append_vals (result, ws, nwc);
g_free (ws);
}
p = g_utf8_next_char (p);
}
convbuf = g_utf16_to_utf8 ((wchar_t *) result->data, result->len, NULL, &convlen, NULL);
g_array_free (result, TRUE);
if (!convbuf)
{
s[0] = '\0';
return 0;
}
if (slen <= convlen)
{
/* Ensure only whole characters are copied into the buffer. */
gchar *end = g_utf8_find_prev_char (convbuf, convbuf + slen);
g_assert (end != NULL);
convlen = end - convbuf;
/* Return 0 because the buffer isn't large enough. */
retval = 0;
}
else
retval = convlen;
memcpy (s, convbuf, convlen);
s[convlen] = '\0';
g_free (convbuf);
return retval;
}
#endif
/**
* g_date_strftime:
* @s: destination buffer
* @slen: buffer size
* @format: format string
* @date: valid #GDate
*
* Generates a printed representation of the date, in a
* [locale][setlocale]-specific way.
* Works just like the platform's C library strftime() function,
* but only accepts date-related formats; time-related formats
* give undefined results. Date must be valid. Unlike strftime()
* (which uses the locale encoding), works on a UTF-8 format
* string and stores a UTF-8 result.
*
* This function does not provide any conversion specifiers in
* addition to those implemented by the platform's C library.
* For example, don't expect that using g_date_strftime() would
* make the \%F provided by the C99 strftime() work on Windows
* where the C library only complies to C89.
*
* Returns: number of characters written to the buffer, or 0 the buffer was too small
*/
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wformat-nonliteral"
gsize
g_date_strftime (gchar *s,
gsize slen,
const gchar *format,
const GDate *d)
{
struct tm tm;
#ifndef G_OS_WIN32
gsize locale_format_len = 0;
gchar *locale_format;
gsize tmplen;
gchar *tmpbuf;
gsize tmpbufsize;
gsize convlen = 0;
gchar *convbuf;
GError *error = NULL;
gsize retval;
#endif
g_return_val_if_fail (g_date_valid (d), 0);
g_return_val_if_fail (slen > 0, 0);
g_return_val_if_fail (format != NULL, 0);
g_return_val_if_fail (s != NULL, 0);
g_date_to_struct_tm (d, &tm);
#ifdef G_OS_WIN32
if (!g_utf8_validate (format, -1, NULL))
{
s[0] = '\0';
return 0;
}
return win32_strftime_helper (d, format, &tm, s, slen);
#else
locale_format = g_locale_from_utf8 (format, -1, NULL, &locale_format_len, &error);
if (error)
{
g_warning (G_STRLOC "Error converting format to locale encoding: %s", error->message);
g_error_free (error);
s[0] = '\0';
return 0;
}
tmpbufsize = MAX (128, locale_format_len * 2);
while (TRUE)
{
tmpbuf = g_malloc (tmpbufsize);
/* Set the first byte to something other than '\0', to be able to
* recognize whether strftime actually failed or just returned "".
*/
tmpbuf[0] = '\1';
tmplen = strftime (tmpbuf, tmpbufsize, locale_format, &tm);
if (tmplen == 0 && tmpbuf[0] != '\0')
{
g_free (tmpbuf);
tmpbufsize *= 2;
if (tmpbufsize > 65536)
{
g_warning (G_STRLOC "Maximum buffer size for g_date_strftime exceeded: giving up");
g_free (locale_format);
s[0] = '\0';
return 0;
}
}
else
break;
}
g_free (locale_format);
convbuf = g_locale_to_utf8 (tmpbuf, tmplen, NULL, &convlen, &error);
g_free (tmpbuf);
if (error)
{
g_warning (G_STRLOC "Error converting results of strftime to UTF-8: %s", error->message);
g_error_free (error);
s[0] = '\0';
return 0;
}
if (slen <= convlen)
{
/* Ensure only whole characters are copied into the buffer.
*/
gchar *end = g_utf8_find_prev_char (convbuf, convbuf + slen);
g_assert (end != NULL);
convlen = end - convbuf;
/* Return 0 because the buffer isn't large enough.
*/
retval = 0;
}
else
retval = convlen;
memcpy (s, convbuf, convlen);
s[convlen] = '\0';
g_free (convbuf);
return retval;
#endif
}
#pragma GCC diagnostic pop
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