f65184802d
* NEW: Update copyright and license string in all source files. git-svn-id: svn://localhost/gambas/trunk@2241 867c0c6c-44f3-4631-809d-bfa615b0a4ec
206 lines
6.1 KiB
C
206 lines
6.1 KiB
C
/***************************************************************************
|
|
|
|
vbdate.c
|
|
|
|
(c) 2000-2003 Nigel Gerrard <nigel@gerrard1123.freeserve.co.uk>
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
This program 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 General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
|
|
***************************************************************************/
|
|
|
|
#define __VBDATE_C
|
|
|
|
#include "vbdate.h"
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
|
|
|
|
#define DATE_YEAR_MIN -4801
|
|
#define DATE_YEAR_MAX 9999
|
|
|
|
/* Helper functions */
|
|
|
|
const char 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 */
|
|
};
|
|
|
|
const short 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 } /* leap year */
|
|
};
|
|
|
|
/* Returns 1 for a leap year, 0 else */
|
|
int date_is_leap_year(short year)
|
|
{
|
|
if (year < 0)
|
|
year += 8001;
|
|
|
|
if ((((year % 4) == 0) && ((year % 100) != 0)) || (year % 400) == 0)
|
|
return 1;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
int date_is_valid(GB_DATE_SERIAL *date)
|
|
{
|
|
return ((date->month >= 1) && (date->month <= 12) &&
|
|
(date->year >= DATE_YEAR_MIN) && (date->year <= DATE_YEAR_MAX) && (date->year != 0) &&
|
|
(date->day >= 1) && (date->day <= days_in_months[date_is_leap_year(date->year)][(short)date->month]) &&
|
|
(date->hour >= 0) && (date->hour <= 23) && (date->min >= 0) && (date->min <= 59) &&
|
|
(date->sec >= 0) && (date->sec <= 59));
|
|
}
|
|
|
|
/** Modulo function that works correctly for negative divisors */
|
|
#define modulo(x,y) ((x)%(y)<0?(x)%(y)+(y):(x)%(y))
|
|
|
|
void DATE_adjust( GB_DATE *vdate, int period, int interval) /* Adjust the date by the interval period */
|
|
{
|
|
|
|
GB_DATE_SERIAL *date;
|
|
int year, month, day;
|
|
date = GB.SplitDate(vdate);
|
|
|
|
switch(period){
|
|
case 0: /* Calendar Month */
|
|
year = ((date->year * 12) + (date->month - 1) + interval)/12;
|
|
month = modulo((date->month - 1)+interval, 12) + 1;
|
|
day = date->day > days_in_months[date_is_leap_year(year)][month] ? days_in_months[date_is_leap_year(year)][month] : date->day;
|
|
date->day = day;
|
|
date->month = month;
|
|
date->year = year;
|
|
GB.MakeDate(date, vdate);
|
|
break;
|
|
case 1: /* days */
|
|
vdate->value.date += interval;
|
|
break;
|
|
case 2: /* Time */
|
|
vdate->value.time += interval;
|
|
break;
|
|
case 3: /* weekdays - in this case weekdays are Mon - Fri */
|
|
vdate->value.date += ( 7 * ( interval / 5));
|
|
date->weekday += ( interval % 5 );
|
|
if (date->weekday > 5){
|
|
date->weekday -= 5;
|
|
vdate->value.date += 2;
|
|
}
|
|
if (date->weekday < 1){
|
|
date->weekday += 5;
|
|
vdate->value.date -= 2;
|
|
}
|
|
vdate->value.date += ( interval % 5);
|
|
break;
|
|
case 4: /* Add year */
|
|
while ( interval != 0){
|
|
if ( interval < 0 ){
|
|
vdate->value.date -= days_in_year[date_is_leap_year(date->year)][13];
|
|
date->year--;
|
|
interval++;
|
|
}
|
|
else {
|
|
vdate->value.date += days_in_year[date_is_leap_year(date->year)][13];
|
|
date->year++;
|
|
interval--;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* Now if time takes it into another day */
|
|
while (vdate->value.time >= 86400000){
|
|
vdate->value.date++;
|
|
vdate->value.time -= 86400000;
|
|
}
|
|
/* Or time is negative so we need to take off a day */
|
|
while (vdate->value.time < 0){
|
|
vdate->value.date--;
|
|
vdate->value.time += 86400000;
|
|
}
|
|
|
|
CLEAR(&date);
|
|
date = GB.SplitDate(vdate);
|
|
|
|
if (!date_is_valid(date)){
|
|
/*printf("Invalid date : year [%i] month [%i] day [%i] hour [%i] min [%i] sec [%i] weekday [%i] msec [%i]\n",
|
|
date->year, date->month, date->day, date->hour, date->min, date->sec, date->weekday, date->msec);*/
|
|
GB.Error("Invalid Date Returned");
|
|
}
|
|
CLEAR(&date);
|
|
|
|
}
|
|
|
|
int DATE_diff( GB_DATE *vdate1, GB_DATE *vdate2, int period)
|
|
{
|
|
GB_DATE_SERIAL *date1, *date2;
|
|
int diff = 0;
|
|
int year1, year2, month1, month2, weekday1, weekday2;
|
|
|
|
date1 = GB.SplitDate(vdate1);
|
|
weekday1 = date1->weekday;
|
|
year1 = date1->year;
|
|
month1 = date1->month;
|
|
|
|
date2 = GB.SplitDate(vdate2);
|
|
weekday2 = date2->weekday;
|
|
year2 = date2->year;
|
|
month2 = date2->month;
|
|
|
|
switch(period){
|
|
case 0: /* Calendar Month */
|
|
diff = ((year1 * 12) + month1) - ((year2 * 12) + month2);
|
|
break;
|
|
case 1: /* days */
|
|
diff = vdate1->value.date - vdate2->value.date;
|
|
break;
|
|
case 2: /* Time */
|
|
diff = ((vdate1->value.date - vdate2->value.date) * 86400000) + (vdate1->value.time - vdate2->value.time);
|
|
break;
|
|
case 3: /* weekdays */
|
|
/* If invalid weekday then find closest valid day:
|
|
* eg. 7 -1, 6 -5*/
|
|
weekday1 == 7 ? weekday1 = 1 : weekday1 == 6 ? weekday1 = 5 : weekday1;
|
|
weekday2 == 7 ? weekday2 = 1 : weekday2 == 6 ? weekday2 = 5 : weekday2;
|
|
|
|
diff = (((vdate1->value.date - vdate2->value.date) / 7) * 5)
|
|
+ (weekday1 - weekday2);
|
|
/* Needs validating */
|
|
break;
|
|
case 4: /* year */
|
|
diff = year1 - year2;
|
|
break;
|
|
case 5: /* Weeks */
|
|
diff = (vdate1->value.date - vdate2->value.date)/7;
|
|
break;
|
|
}
|
|
CLEAR(&date1);
|
|
CLEAR(&date2);
|
|
return diff;
|
|
}
|
|
|
|
/* End Helper functions */
|
|
|
|
/*
|
|
GB_DESC CVbDateDesc[] =
|
|
{
|
|
GB_DECLARE("Vb", 0), GB_NOT_CREATABLE(),
|
|
|
|
GB_STATIC_METHOD("DateAdd", "d", CVB_DateAdd, "(period)s(interval)i(Date)v"),
|
|
GB_STATIC_METHOD("DateDiff", "i", CVB_DateDiff, "(period)s(Date1)v(Date2)v"),
|
|
|
|
GB_END_DECLARE
|
|
};*/
|
|
|