1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
21 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
22 * file for a list of people on the GLib Team. See the ChangeLog
23 * files for a list of changes. These files are distributed with
24 * GLib at ftp://ftp.gtk.org/pub/gtk/.
30 #include <glib/gquark.h>
36 * Date calculations (not time for now, to be resolved). These are a
37 * mutant combination of Steffen Beyer's DateCalc routines
38 * (http://www.perl.com/CPAN/authors/id/STBEY/) and Jon Trowbridge's
39 * date routines (written for in-house software). Written by Havoc
40 * Pennington <hp@pobox.com>
44 typedef guint16 GDateYear
;
45 typedef guint8 GDateDay
; /* day of the month */
46 typedef struct _GDate GDate
;
47 /* make struct tm known without having to include time.h */
50 /* enum used to specify order of appearance in parsed date strings */
58 /* actual week and month values */
61 G_DATE_BAD_WEEKDAY
= 0,
87 #define G_DATE_BAD_JULIAN 0U
88 #define G_DATE_BAD_DAY 0U
89 #define G_DATE_BAD_YEAR 0U
91 /* Note: directly manipulating structs is generally a bad idea, but
92 * in this case it's an *incredibly* bad idea, because all or part
93 * of this struct can be invalid at any given time. Use the functions,
94 * or you will get hosed, I promise.
98 guint julian_days
: 32; /* julian days representation - we use a
99 * bitfield hoping that 64 bit platforms
100 * will pack this whole struct in one big
104 guint julian
: 1; /* julian is valid */
105 guint dmy
: 1; /* dmy is valid */
107 /* DMY representation */
113 /* g_date_new() returns an invalid date, you then have to _set() stuff
114 * to get a usable object. You can also allocate a GDate statically,
115 * then call g_date_clear() to initialize.
117 GDate
* g_date_new (void);
118 GDate
* g_date_new_dmy (GDateDay day
,
121 GDate
* g_date_new_julian (guint32 julian_day
);
122 void g_date_free (GDate
*date
);
124 /* check g_date_valid() after doing an operation that might fail, like
125 * _parse. Almost all g_date operations are undefined on invalid
126 * dates (the exceptions are the mutators, since you need those to
127 * return to validity).
129 gboolean
g_date_valid (const GDate
*date
);
130 gboolean
g_date_valid_day (GDateDay day
) G_GNUC_CONST
;
131 gboolean
g_date_valid_month (GDateMonth month
) G_GNUC_CONST
;
132 gboolean
g_date_valid_year (GDateYear year
) G_GNUC_CONST
;
133 gboolean
g_date_valid_weekday (GDateWeekday weekday
) G_GNUC_CONST
;
134 gboolean
g_date_valid_julian (guint32 julian_date
) G_GNUC_CONST
;
135 gboolean
g_date_valid_dmy (GDateDay day
,
137 GDateYear year
) G_GNUC_CONST
;
139 GDateWeekday
g_date_get_weekday (const GDate
*date
);
140 GDateMonth
g_date_get_month (const GDate
*date
);
141 GDateYear
g_date_get_year (const GDate
*date
);
142 GDateDay
g_date_get_day (const GDate
*date
);
143 guint32
g_date_get_julian (const GDate
*date
);
144 guint
g_date_get_day_of_year (const GDate
*date
);
145 /* First monday/sunday is the start of week 1; if we haven't reached
146 * that day, return 0. These are not ISO weeks of the year; that
147 * routine needs to be added.
148 * these functions return the number of weeks, starting on the
151 guint
g_date_get_monday_week_of_year (const GDate
*date
);
152 guint
g_date_get_sunday_week_of_year (const GDate
*date
);
153 guint
g_date_get_iso8601_week_of_year (const GDate
*date
);
155 /* If you create a static date struct you need to clear it to get it
156 * in a sane state before use. You can clear a whole array at
157 * once with the ndates argument.
159 void g_date_clear (GDate
*date
,
162 /* The parse routine is meant for dates typed in by a user, so it
163 * permits many formats but tries to catch common typos. If your data
164 * needs to be strictly validated, it is not an appropriate function.
166 void g_date_set_parse (GDate
*date
,
168 void g_date_set_time (GDate
*date
,
170 void g_date_set_month (GDate
*date
,
172 void g_date_set_day (GDate
*date
,
174 void g_date_set_year (GDate
*date
,
176 void g_date_set_dmy (GDate
*date
,
180 void g_date_set_julian (GDate
*date
,
181 guint32 julian_date
);
182 gboolean
g_date_is_first_of_month (const GDate
*date
);
183 gboolean
g_date_is_last_of_month (const GDate
*date
);
185 /* To go forward by some number of weeks just go forward weeks*7 days */
186 void g_date_add_days (GDate
*date
,
188 void g_date_subtract_days (GDate
*date
,
191 /* If you add/sub months while day > 28, the day might change */
192 void g_date_add_months (GDate
*date
,
194 void g_date_subtract_months (GDate
*date
,
197 /* If it's feb 29, changing years can move you to the 28th */
198 void g_date_add_years (GDate
*date
,
200 void g_date_subtract_years (GDate
*date
,
202 gboolean
g_date_is_leap_year (GDateYear year
) G_GNUC_CONST
;
203 guint8
g_date_get_days_in_month (GDateMonth month
,
204 GDateYear year
) G_GNUC_CONST
;
205 guint8
g_date_get_monday_weeks_in_year (GDateYear year
) G_GNUC_CONST
;
206 guint8
g_date_get_sunday_weeks_in_year (GDateYear year
) G_GNUC_CONST
;
208 /* Returns the number of days between the two dates. If date2 comes
209 before date1, a negative value is return. */
210 gint
g_date_days_between (const GDate
*date1
,
213 /* qsort-friendly (with a cast...) */
214 gint
g_date_compare (const GDate
*lhs
,
216 void g_date_to_struct_tm (const GDate
*date
,
219 void g_date_clamp (GDate
*date
,
220 const GDate
*min_date
,
221 const GDate
*max_date
);
223 /* Swap date1 and date2's values if date1 > date2. */
224 void g_date_order (GDate
*date1
, GDate
*date2
);
226 /* Just like strftime() except you can only use date-related formats.
227 * Using a time format is undefined.
229 gsize
g_date_strftime (gchar
*s
,
234 #ifndef G_DISABLE_DEPRECATED
236 #define g_date_weekday g_date_get_weekday
237 #define g_date_month g_date_get_month
238 #define g_date_year g_date_get_year
239 #define g_date_day g_date_get_day
240 #define g_date_julian g_date_get_julian
241 #define g_date_day_of_year g_date_get_day_of_year
242 #define g_date_monday_week_of_year g_date_get_monday_week_of_year
243 #define g_date_sunday_week_of_year g_date_get_sunday_week_of_year
244 #define g_date_days_in_month g_date_get_days_in_month
245 #define g_date_monday_weeks_in_year g_date_get_monday_weeks_in_year
246 #define g_date_sunday_weeks_in_year g_date_get_sunday_weeks_in_year
248 #endif /* G_DISABLE_DEPRECATED */
252 #endif /* __G_DATE_H__ */