/* 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 Library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library 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. */ #include "glib.h" #include #include #include #include GDate* g_date_new () { GDate *d = g_new0 (GDate, 1); /* happily, 0 is the invalid flag for everything. */ return d; } GDate* g_date_new_mdy (GDateMonth m, GDateDay day, GDateYear y) { GDate *d; g_return_val_if_fail (g_date_valid_mdy (m, day, y), NULL); d = g_new (GDate, 1); d->julian = FALSE; d->mdy = TRUE; d->month = m; d->day = day; d->year = y; g_assert (g_date_valid (d)); return d; } GDate* g_date_new_julian (guint32 j) { GDate *d; g_return_val_if_fail (g_date_valid_julian (j), NULL); d = g_new (GDate, 1); d->julian = TRUE; d->mdy = FALSE; d->julian_days = j; g_assert (g_date_valid (d)); return d; } void g_date_free (GDate *d) { g_return_if_fail (d != NULL); g_free (d); } gboolean g_date_valid (GDate *d) { g_return_val_if_fail (d != NULL, FALSE); if (d->julian && d->mdy) { return ( g_date_valid_julian (d->julian_days) && g_date_valid_mdy (d->month, d->day, d->year) ); } else if (d->mdy) { return g_date_valid_mdy (d->month, d->day, d->year); } else if (d->julian) { return g_date_valid_julian (d->julian_days); } else return FALSE; } 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 } }; gboolean g_date_valid_month (GDateMonth m) { return ( (m > G_DATE_BAD_MONTH) && (m < 13) ); } gboolean g_date_valid_year (GDateYear y) { return ( y > G_DATE_BAD_YEAR ); } gboolean g_date_valid_day (GDateDay d) { return ( (d > G_DATE_BAD_DAY) && (d < 32) ); } gboolean g_date_valid_weekday (GDateWeekday w) { return ( (w > G_DATE_BAD_WEEKDAY) && (w < 8) ); } gboolean g_date_valid_julian (guint32 j) { return (j > G_DATE_BAD_JULIAN); } gboolean g_date_valid_mdy (GDateMonth m, GDateDay d, 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 (GDate *d) { GDateYear year; gint index; g_return_if_fail (d != NULL); g_return_if_fail (d->mdy); g_return_if_fail (!d->julian); g_return_if_fail (g_date_valid_mdy (d->month, d->day, 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 */ index = g_date_is_leap_year (d->year) ? 1 : 0; d->julian_days += days_in_year[index][d->month] + d->day; g_return_if_fail (g_date_valid_julian (d->julian_days)); d->julian = TRUE; } static void g_date_update_mdy (GDate *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->mdy); 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_mdy (m, day, y)) { g_warning ("\nOOPS julian: %u computed mdy: %u %u %u\n", d->julian_days, m, day, y); } #endif d->month = m; d->day = day; d->year = y; d->mdy = TRUE; } GDateWeekday g_date_weekday (GDate *d) { g_return_val_if_fail (d != NULL, G_DATE_BAD_WEEKDAY); 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; } GDateMonth g_date_month (GDate *d) { g_return_val_if_fail (d != NULL, G_DATE_BAD_MONTH); g_return_val_if_fail (g_date_valid (d), G_DATE_BAD_MONTH); if (!d->mdy) { g_date_update_mdy (d); } g_return_val_if_fail (d->mdy, G_DATE_BAD_MONTH); return d->month; } GDateYear g_date_year (GDate *d) { g_return_val_if_fail (d != NULL, G_DATE_BAD_YEAR); g_return_val_if_fail (g_date_valid (d), G_DATE_BAD_YEAR); if (!d->mdy) { g_date_update_mdy (d); } g_return_val_if_fail (d->mdy, G_DATE_BAD_YEAR); return d->year; } GDateDay g_date_day (GDate *d) { g_return_val_if_fail (d != NULL, G_DATE_BAD_DAY); g_return_val_if_fail (g_date_valid (d), G_DATE_BAD_DAY); if (!d->mdy) { g_date_update_mdy (d); } g_return_val_if_fail (d->mdy, G_DATE_BAD_DAY); return d->day; } guint32 g_date_julian (GDate *d) { g_return_val_if_fail (d != NULL, G_DATE_BAD_JULIAN); 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; } guint g_date_day_of_year (GDate *d) { gint index; g_return_val_if_fail (d != NULL, 0); g_return_val_if_fail (g_date_valid (d), 0); if (!d->mdy) { g_date_update_mdy (d); } g_return_val_if_fail (d->mdy, 0); index = g_date_is_leap_year (d->year) ? 1 : 0; return (days_in_year[index][d->month] + d->day); } guint g_date_monday_week_of_year (GDate *d) { GDateWeekday wd; guint day; GDate first; g_return_val_if_fail (d != NULL, 0); g_return_val_if_fail (g_date_valid (d), 0); if (!d->mdy) { g_date_update_mdy (d); } g_return_val_if_fail (d->mdy, 0); g_date_clear (&first, 1); g_date_set_mdy (&first, 1, 1, d->year); wd = g_date_weekday (&first) - 1; /* make Monday day 0 */ day = g_date_day_of_year (d) - 1; return ((day + wd)/7U + (wd == 0 ? 1 : 0)); } guint g_date_sunday_week_of_year (GDate *d) { GDateWeekday wd; guint day; GDate first; g_return_val_if_fail (d != NULL, 0); g_return_val_if_fail (g_date_valid (d), 0); if (!d->mdy) { g_date_update_mdy (d); } g_return_val_if_fail (d->mdy, 0); g_date_clear (&first, 1); g_date_set_mdy (&first, 1, 1, d->year); wd = g_date_weekday (&first); if (wd == 7) wd = 0; /* make Sunday day 0 */ day = g_date_day_of_year (d) - 1; return ((day + wd)/7U + (wd == 0 ? 1 : 0)); } 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)); } /* 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] = { "Error", NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL }; static gchar *short_month_names[13] = { "Error", NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 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 GDateMDY mdy_order[3] = { G_DATE_MONTH, G_DATE_DAY, 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 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; struct _GDateParseTokens { gint num_ints; gint n[3]; guint month; }; typedef struct _GDateParseTokens GDateParseTokens; #define NUM_LEN 10 static void g_date_fill_parse_tokens (const gchar *str, GDateParseTokens *pt) { gchar num[4][NUM_LEN+1]; gint i; const gchar *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 = str; pt->num_ints = 0; while (*s && pt->num_ints < 4) { i = 0; while (*s && 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 lcstr[128]; int i = 1; strncpy (lcstr, str, 127); g_strdown (lcstr); while (i < 13) { if (long_month_names[i] != NULL) { const gchar *found = strstr (lcstr, long_month_names[i]); if (found != NULL) { pt->month = i; return; } } if (short_month_names[i] != NULL) { const gchar *found = strstr (lcstr, short_month_names[i]); if (found != NULL) { pt->month = i; return; } } ++i; } } } 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); while (i < 13) { g_date_set_mdy (&d, i, 1, 1); g_return_if_fail (g_date_valid (&d)); g_date_strftime (buf, 127, "%b", &d); g_free (short_month_names[i]); g_strdown (buf); short_month_names[i] = g_strdup (buf); g_date_strftime (buf, 127, "%B", &d); g_free (long_month_names[i]); g_strdown (buf); long_month_names[i] = g_strdup (buf); ++i; } /* Determine MDY order */ g_date_set_mdy (&d, 7, 4, 1776); /* had to pick a random day */ 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: mdy_order[i] = G_DATE_MONTH; break; case 4: mdy_order[i] = G_DATE_DAY; break; case 76: using_twodigit_years = TRUE; /* FALL THRU */ case 1776: mdy_order[i] = G_DATE_YEAR; break; default: /* leave it unchanged */ break; } ++i; } #ifdef G_ENABLE_DEBUG g_print ("\n**GDate prepared a new set of locale-specific parse rules.\n"); i = 1; while (i < 13) { g_print (" %s %s\n", long_month_names[i], short_month_names[i]); ++i; } if (using_twodigit_years) { g_print ("**Using twodigit years with cutoff year: %u\n", twodigit_start_year); } { gchar *strings[3]; i = 0; while (i < 3) { switch (mdy_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; } g_print ("**Order: %s, %s, %s\n", strings[0], strings[1], strings[2]); g_print ("**Sample date in this locale: `%s'\n\n", buf); } #endif } g_date_fill_parse_tokens (str, pt); } 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_date_prepare_to_parse (str, &pt); #ifdef G_ENABLE_DEBUG g_print ("Found %d ints, `%d' `%d' `%d' and written out month %d\n", pt.num_ints, pt.n[0], pt.n[1], pt.n[2], pt.month); #endif if (pt.num_ints == 4) 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 (mdy_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 (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_mdy (m, day, 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 == 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_mdy (m, day, y)) { d->month = m; d->day = day; d->year = y; d->mdy = TRUE; } #ifdef G_ENABLE_DEBUG else g_print ("Rejected MDY %u %u %u\n", m, day, y); #endif } void g_date_set_time (GDate *d, time_t t) { struct tm *tm; g_return_if_fail (d != NULL); tm = localtime (&t); if (tm) { d->julian = FALSE; d->month = tm->tm_mon + 1; d->day = tm->tm_mday; d->year = tm->tm_year + 1900; g_return_if_fail (g_date_valid_mdy (d->month, d->day, d->year)); d->mdy = TRUE; } else { g_date_clear (d, 1); } } void g_date_set_month (GDate *d, GDateMonth m) { g_return_if_fail (d != NULL); g_return_if_fail (g_date_valid_month (m)); d->julian = FALSE; d->month = m; if (g_date_valid_mdy (d->month, d->day, d->year)) d->mdy = TRUE; else d->mdy = FALSE; } void g_date_set_day (GDate *d, GDateDay day) { g_return_if_fail (d != NULL); g_return_if_fail (g_date_valid_day (day)); d->julian = FALSE; d->day = day; if (g_date_valid_mdy (d->month, d->day, d->year)) d->mdy = TRUE; else d->mdy = FALSE; } void g_date_set_year (GDate *d, GDateYear y) { g_return_if_fail (d != NULL); g_return_if_fail (g_date_valid_year (y)); d->julian = FALSE; d->year = y; if (g_date_valid_mdy (d->month, d->day, d->year)) d->mdy = TRUE; else d->mdy = FALSE; } void g_date_set_mdy (GDate *d, GDateMonth m, GDateDay day, GDateYear y) { g_return_if_fail (d != NULL); g_return_if_fail (g_date_valid_mdy (m, day, y)); d->julian = FALSE; d->month = m; d->day = day; d->year = y; d->mdy = TRUE; } 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->mdy = FALSE; } gboolean g_date_is_first_of_month (GDate *d) { g_return_val_if_fail (d != NULL, FALSE); g_return_val_if_fail (g_date_valid (d), FALSE); if (!d->mdy) { g_date_update_mdy (d); } g_return_val_if_fail (d->mdy, FALSE); if (d->day == 1) return TRUE; else return FALSE; } gboolean g_date_is_last_of_month (GDate *d) { gint index; g_return_val_if_fail (d != NULL, FALSE); g_return_val_if_fail (g_date_valid (d), FALSE); if (!d->mdy) { g_date_update_mdy (d); } g_return_val_if_fail (d->mdy, FALSE); index = g_date_is_leap_year (d->year) ? 1 : 0; if (d->day == days_in_months[index][d->month]) return TRUE; else return FALSE; } void g_date_add_days (GDate *d, guint ndays) { g_return_if_fail (d != NULL); 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->mdy = FALSE; } void g_date_subtract_days (GDate *d, guint ndays) { g_return_if_fail (d != NULL); 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->mdy = FALSE; } void g_date_add_months (GDate *d, guint nmonths) { guint years, months; gint index; g_return_if_fail (d != NULL); g_return_if_fail (g_date_valid (d)); if (!d->mdy) { g_date_update_mdy (d); } g_return_if_fail (d->mdy); nmonths += d->month - 1; years = nmonths/12; months = nmonths%12; d->month = months + 1; d->year += years; index = g_date_is_leap_year (d->year) ? 1 : 0; if (d->day > days_in_months[index][d->month]) d->day = days_in_months[index][d->month]; d->julian = FALSE; g_return_if_fail (g_date_valid (d)); } void g_date_subtract_months (GDate *d, guint nmonths) { guint years, months; gint index; g_return_if_fail (d != NULL); g_return_if_fail (g_date_valid (d)); if (!d->mdy) { g_date_update_mdy (d); } g_return_if_fail (d->mdy); 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; } index = g_date_is_leap_year (d->year) ? 1 : 0; if (d->day > days_in_months[index][d->month]) d->day = days_in_months[index][d->month]; d->julian = FALSE; g_return_if_fail (g_date_valid (d)); } void g_date_add_years (GDate *d, guint nyears) { g_return_if_fail (d != NULL); g_return_if_fail (g_date_valid (d)); if (!d->mdy) { g_date_update_mdy (d); } g_return_if_fail (d->mdy); d->year += nyears; if (d->month == 2 && d->day == 29) { if (!g_date_is_leap_year (d->year)) { d->day = 28; } } d->julian = FALSE; } void g_date_subtract_years (GDate *d, guint nyears) { g_return_if_fail (d != NULL); g_return_if_fail (g_date_valid (d)); if (!d->mdy) { g_date_update_mdy (d); } g_return_if_fail (d->mdy); 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; } 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 ); } guint8 g_date_days_in_month (GDateMonth month, GDateYear year) { gint index; g_return_val_if_fail (g_date_valid_year (year), 0); g_return_val_if_fail (g_date_valid_month (month), 0); index = g_date_is_leap_year (year) ? 1 : 0; return days_in_months[index][month]; } guint8 g_date_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_mdy (&d, 1, 1, year); if (g_date_weekday (&d) == G_DATE_MONDAY) return 53; g_date_set_mdy (&d, 12, 31, year); if (g_date_weekday (&d) == G_DATE_MONDAY) return 53; if (g_date_is_leap_year (year)) { g_date_set_mdy (&d, 1, 2, year); if (g_date_weekday (&d) == G_DATE_MONDAY) return 53; g_date_set_mdy (&d, 12, 30, year); if (g_date_weekday (&d) == G_DATE_MONDAY) return 53; } return 52; } guint8 g_date_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_mdy (&d, 1, 1, year); if (g_date_weekday (&d) == G_DATE_SUNDAY) return 53; g_date_set_mdy (&d, 12, 31, year); if (g_date_weekday (&d) == G_DATE_SUNDAY) return 53; if (g_date_is_leap_year (year)) { g_date_set_mdy (&d, 1, 2, year); if (g_date_weekday (&d) == G_DATE_SUNDAY) return 53; g_date_set_mdy (&d, 12, 30, year); if (g_date_weekday (&d) == G_DATE_SUNDAY) return 53; } return 52; } gint g_date_compare (GDate *lhs, 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->mdy && rhs->mdy) { 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 */ } void g_date_to_struct_tm (GDate *d, struct tm *tm) { GDateWeekday day; g_return_if_fail (d != NULL); g_return_if_fail (g_date_valid (d)); g_return_if_fail (tm != NULL); if (!d->mdy) { g_date_update_mdy (d); } g_return_if_fail (d->mdy); /* 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_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_day_of_year (d) - 1; /* 0 to 365 */ tm->tm_isdst = -1; /* -1 means "information not available" */ } gsize g_date_strftime (gchar *s, gsize slen, const gchar *format, GDate *d) { struct tm tm; gsize retval; g_return_val_if_fail (d != NULL, 0); g_return_val_if_fail (g_date_valid (d), 0); g_return_val_if_fail (slen > 0, 0); g_return_val_if_fail (format != 0, 0); g_return_val_if_fail (s != 0, 0); g_date_to_struct_tm (d, &tm); retval = strftime (s, slen, format, &tm); if (retval == 0) { /* If retval == 0, the contents of s are undefined. We define * them. */ s[0] = '\0'; } return retval; }