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Diffstat (limited to 'glib/glib/gdate.c')
| -rw-r--r-- | glib/glib/gdate.c | 2551 |
1 files changed, 2551 insertions, 0 deletions
diff --git a/glib/glib/gdate.c b/glib/glib/gdate.c new file mode 100644 index 0000000..d9b25f3 --- /dev/null +++ b/glib/glib/gdate.c @@ -0,0 +1,2551 @@ +/* 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/. + */ + +/* + * 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 <emphasis>day</emphasis>. + * + * 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 + * <emphasis>invalid</emphasis>, 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. + * + * <emphasis>It is very important to use the API to access the #GDate + * struct.</emphasis> 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 <structname>struct timeval</structname> returned by + * the gettimeofday() UNIX system call. + * + * GLib is attempting to unify around the use of 64bit integers to + * represent microsecond-precision time. As such, this type will be + * removed from a future version of GLib. + */ + +/** + * 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 + * <structname>GDate</structname> 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 <type>time_t</type>. It has been deprecated + * since it is <emphasis>not</emphasis> equivalent to <type>time_t</type> + * on 64-bit platforms with a 64-bit <type>time_t</type>. + * Unrelated to #GTimer. + * + * Note that <type>GTime</type> is defined to always be a 32bit integer, + * unlike <type>time_t</type> which may be 64bit on some systems. + * Therefore, <type>GTime</type> will overflow in the year 2038, and + * you cannot use the address of a <type>GTime</type> variable as argument + * to the UNIX time() function. Instead, do the following: + * |[ + * time_t ttime; + * GTime gtime; + * + * time (&ttime); + * gtime = (GTime)ttime; + * ]| + */ + +/** + * 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_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) +{ + 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); + 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 ("\nOOPS julian: %u computed dmy: %u %u %u\n", + 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 being 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 *short_month_names[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; + +#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) + { + gchar *casefold; + gchar *normalized; + + casefold = g_utf8_casefold (str, -1); + normalized = g_utf8_normalize (casefold, -1, G_NORMALIZE_ALL); + g_free (casefold); + + i = 1; + while (i < 13) + { + if (long_month_names[i] != NULL) + { + const gchar *found = strstr (normalized, long_month_names[i]); + + if (found != NULL) + { + pt->month = i; + break; + } + } + + if (short_month_names[i] != NULL) + { + const gchar *found = strstr (normalized, short_month_names[i]); + + if (found != NULL) + { + pt->month = i; + break; + } + } + + ++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, 1); + + 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); + + ++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); + + 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; + } + 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 <link linkend="setlocale">current locale</link> + * 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: <type>time_t</type> 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: + * |[ + * g_date_set_time_t (date, time (NULL)); + * ]| + * + * 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. + */ +void +g_date_set_time (GDate *date, + GTime time_) +{ + g_date_set_time_t (date, (time_t) time_); +} + +/** + * 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 + */ +void +g_date_set_time_val (GDate *date, + GTimeVal *timeval) +{ + g_date_set_time_t (date, (time_t) timeval->tv_sec); +} + +/** + * 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); + + 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); + + nmonths += d->month - 1; + + years = nmonths/12; + months = nmonths%12; + + 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); + + 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); + + 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); + 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. + * <footnote><para>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.</para></footnote> + * + * 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 <structname>struct tm</structname> from + * @tm: <structname>struct tm</structname> to fill + * + * Fills in the date-related bits of a <structname>struct tm</structname> + * 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); + + /* 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 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; + 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; + } + + c = g_utf8_get_char (p); + if (c == 'E' || c == 'O') + { + /* Ignore modified conversion specifiers for now. */ + 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': + n = GetLocaleInfoW (lcid, LOCALE_SABBREVMONTHNAME1+systemtime.wMonth-1, NULL, 0); + g_array_set_size (result, result->len + n); + GetLocaleInfoW (lcid, LOCALE_SABBREVMONTHNAME1+systemtime.wMonth-1, ((wchar_t *) result->data) + result->len - n, n); + g_array_set_size (result, result->len - 1); + break; + case 'B': + n = GetLocaleInfoW (lcid, LOCALE_SMONTHNAME1+systemtime.wMonth-1, NULL, 0); + g_array_set_size (result, result->len + n); + GetLocaleInfoW (lcid, LOCALE_SMONTHNAME1+systemtime.wMonth-1, ((wchar_t *) result->data) + result->len - n, n); + g_array_set_size (result, result->len - 1); + 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 + * <link linkend="setlocale">locale</link>-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 + */ +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\n", 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\n"); + 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\n", 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 +} |