/* 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 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, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ /* * 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/. */ #ifndef __G_DATE_H__ #define __G_DATE_H__ #include G_BEGIN_DECLS /* GDate * * Date calculations (not time for now, to be resolved). These are a * mutant combination of Steffen Beyer's DateCalc routines * (http://www.perl.com/CPAN/authors/id/STBEY/) and Jon Trowbridge's * date routines (written for in-house software). Written by Havoc * Pennington */ typedef gint32 GTime; typedef guint16 GDateYear; typedef guint8 GDateDay; /* day of the month */ typedef struct _GDate GDate; /* make struct tm known without having to include time.h */ struct tm; /* enum used to specify order of appearance in parsed date strings */ typedef enum { G_DATE_DAY = 0, G_DATE_MONTH = 1, G_DATE_YEAR = 2 } GDateDMY; /* actual week and month values */ typedef enum { G_DATE_BAD_WEEKDAY = 0, G_DATE_MONDAY = 1, G_DATE_TUESDAY = 2, G_DATE_WEDNESDAY = 3, G_DATE_THURSDAY = 4, G_DATE_FRIDAY = 5, G_DATE_SATURDAY = 6, G_DATE_SUNDAY = 7 } GDateWeekday; typedef enum { G_DATE_BAD_MONTH = 0, G_DATE_JANUARY = 1, G_DATE_FEBRUARY = 2, G_DATE_MARCH = 3, G_DATE_APRIL = 4, G_DATE_MAY = 5, G_DATE_JUNE = 6, G_DATE_JULY = 7, G_DATE_AUGUST = 8, G_DATE_SEPTEMBER = 9, G_DATE_OCTOBER = 10, G_DATE_NOVEMBER = 11, G_DATE_DECEMBER = 12 } GDateMonth; #define G_DATE_BAD_JULIAN 0U #define G_DATE_BAD_DAY 0U #define G_DATE_BAD_YEAR 0U /* Note: directly manipulating structs is generally a bad idea, but * in this case it's an *incredibly* bad idea, because all or part * of this struct can be invalid at any given time. Use the functions, * or you will get hosed, I promise. */ struct _GDate { guint julian_days : 32; /* julian days representation - we use a * bitfield hoping that 64 bit platforms * will pack this whole struct in one big * int */ guint julian : 1; /* julian is valid */ guint dmy : 1; /* dmy is valid */ /* DMY representation */ guint day : 6; guint month : 4; guint year : 16; }; /* g_date_new() returns an invalid date, you then have to _set() stuff * to get a usable object. You can also allocate a GDate statically, * then call g_date_clear() to initialize. */ GDate* g_date_new (void); GDate* g_date_new_dmy (GDateDay day, GDateMonth month, GDateYear year); GDate* g_date_new_julian (guint32 julian_day); void g_date_free (GDate *date); /* check g_date_valid() after doing an operation that might fail, like * _parse. Almost all g_date operations are undefined on invalid * dates (the exceptions are the mutators, since you need those to * return to validity). */ gboolean g_date_valid (GDate *date); gboolean g_date_valid_day (GDateDay day) G_GNUC_CONST; gboolean g_date_valid_month (GDateMonth month) G_GNUC_CONST; gboolean g_date_valid_year (GDateYear year) G_GNUC_CONST; gboolean g_date_valid_weekday (GDateWeekday weekday) G_GNUC_CONST; gboolean g_date_valid_julian (guint32 julian_date) G_GNUC_CONST; gboolean g_date_valid_dmy (GDateDay day, GDateMonth month, GDateYear year) G_GNUC_CONST; GDateWeekday g_date_get_weekday (GDate *date); GDateMonth g_date_get_month (GDate *date); GDateYear g_date_get_year (GDate *date); GDateDay g_date_get_day (GDate *date); guint32 g_date_get_julian (GDate *date); guint g_date_get_day_of_year (GDate *date); /* First monday/sunday is the start of week 1; if we haven't reached * that day, return 0. These are not ISO weeks of the year; that * routine needs to be added. * these functions return the number of weeks, starting on the * corrsponding day */ guint g_date_get_monday_week_of_year (GDate *date); guint g_date_get_sunday_week_of_year (GDate *date); /* If you create a static date struct you need to clear it to get it * in a sane state before use. You can clear a whole array at * once with the ndates argument. */ void g_date_clear (GDate *date, guint n_dates); /* The parse routine is meant for dates typed in by a user, so it * permits many formats but tries to catch common typos. If your data * needs to be strictly validated, it is not an appropriate function. */ void g_date_set_parse (GDate *date, const gchar *str); void g_date_set_time (GDate *date, GTime time); void g_date_set_month (GDate *date, GDateMonth month); void g_date_set_day (GDate *date, GDateDay day); void g_date_set_year (GDate *date, GDateYear year); void g_date_set_dmy (GDate *date, GDateDay day, GDateMonth month, GDateYear y); void g_date_set_julian (GDate *date, guint32 julian_date); gboolean g_date_is_first_of_month (GDate *date); gboolean g_date_is_last_of_month (GDate *date); /* To go forward by some number of weeks just go forward weeks*7 days */ void g_date_add_days (GDate *date, guint n_days); void g_date_subtract_days (GDate *date, guint n_days); /* If you add/sub months while day > 28, the day might change */ void g_date_add_months (GDate *date, guint n_months); void g_date_subtract_months (GDate *date, guint n_months); /* If it's feb 29, changing years can move you to the 28th */ void g_date_add_years (GDate *date, guint n_years); void g_date_subtract_years (GDate *date, guint n_years); gboolean g_date_is_leap_year (GDateYear year) G_GNUC_CONST; guint8 g_date_get_days_in_month (GDateMonth month, GDateYear year) G_GNUC_CONST; guint8 g_date_get_monday_weeks_in_year (GDateYear year) G_GNUC_CONST; guint8 g_date_get_sunday_weeks_in_year (GDateYear year) G_GNUC_CONST; /* qsort-friendly (with a cast...) */ gint g_date_compare (GDate *lhs, GDate *rhs); void g_date_to_struct_tm (GDate *date, struct tm *tm); /* Just like strftime() except you can only use date-related formats. * Using a time format is undefined. */ gsize g_date_strftime (gchar *s, gsize slen, const gchar *format, GDate *date); G_END_DECLS #endif /* __G_DATE_H__ */