/* * $Id$ */ /* * Harbour Project source code: * The Date conversion module * * Copyright 1999 Antonio Linares * www - http://www.harbour-project.org * * 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 software; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307 USA (or visit the web site http://www.gnu.org/). * * As a special exception, the Harbour Project gives permission for * additional uses of the text contained in its release of Harbour. * * The exception is that, if you link the Harbour libraries with other * files to produce an executable, this does not by itself cause the * resulting executable to be covered by the GNU General Public License. * Your use of that executable is in no way restricted on account of * linking the Harbour library code into it. * * This exception does not however invalidate any other reasons why * the executable file might be covered by the GNU General Public License. * * This exception applies only to the code released by the Harbour * Project under the name Harbour. If you copy code from other * Harbour Project or Free Software Foundation releases into a copy of * Harbour, as the General Public License permits, the exception does * not apply to the code that you add in this way. To avoid misleading * anyone as to the status of such modified files, you must delete * this exception notice from them. * * If you write modifications of your own for Harbour, it is your choice * whether to permit this exception to apply to your modifications. * If you do not wish that, delete this exception notice. * * Copyright 1999-2001 Viktor Szakats * hb_dateEncStr() * hb_dateDecStr() * hb_dateStrPut() * hb_dateStrGet() * */ #include "hbapi.h" #include "hbdate.h" #ifdef HB_C52_STRICT #define HB_DATE_YEAR_LIMIT 2999 #else #define HB_DATE_YEAR_LIMIT 9999 #endif #define HB_STR_DATE_BASE 1721060 /* 0000/01/01 */ HB_EXPORT LONG hb_dateEncode( int iYear, int iMonth, int iDay ) { HB_TRACE(HB_TR_DEBUG, ("hb_dateEncode(%d, %d, %d)", iYear, iMonth, iDay)); /* Perform date validation */ if( iYear >= 0 && iYear <= HB_DATE_YEAR_LIMIT && iMonth >= 1 && iMonth <= 12 && iDay >= 1 ) { /* Month, year, and lower day limits are simple, but upper day limit is dependent upon month and leap year */ static int auiDayLimit[ 12 ] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; if( iDay <= auiDayLimit[ iMonth - 1 ] || ( iDay == 29 && iMonth == 2 && ( iYear & 3 ) == 0 && ( iYear % 100 != 0 || iYear % 400 == 0 ) ) ) { int iFactor = ( iMonth < 3 ) ? -1 : 0; return ( ( LONG )( iFactor + 4800 + iYear ) * 1461 / 4 ) + ( ( LONG )( iMonth - 2 - ( iFactor * 12 ) ) * 367 ) / 12 - ( ( LONG )( ( iFactor + 4900 + iYear ) / 100 ) * 3 / 4 ) + ( LONG ) iDay - 32075; } } return 0; } HB_EXPORT void hb_dateDecode( LONG lJulian, int *piYear, int *piMonth, int *piDay ) { HB_TRACE(HB_TR_DEBUG, ("hb_dateDecode(%ld, %p, %p, %p)", lJulian, piYear, piMonth, piDay)); if( lJulian >= HB_STR_DATE_BASE ) { LONG U, V, W, X; lJulian += 68569; W = ( lJulian * 4 ) / 146097; lJulian -= ( ( 146097 * W ) + 3 ) / 4; X = 4000 * ( lJulian + 1 ) / 1461001; lJulian -= ( ( 1461 * X ) / 4 ) - 31; V = 80 * lJulian / 2447; U = V / 11; *piYear = (int) ( X + U + ( W - 49 ) * 100 ); *piMonth = (int) ( V + 2 - ( U * 12 ) ); *piDay = (int) ( lJulian - ( 2447 * V / 80 ) ); } else { *piYear = *piMonth = *piDay = 0; } } HB_EXPORT void hb_dateStrPut( char * szDate, int iYear, int iMonth, int iDay ) { HB_TRACE(HB_TR_DEBUG, ("hb_dateStrPut(%p, %d, %d, %d)", szDate, iYear, iMonth, iDay)); if( iYear >= 0 && iMonth > 0 && iDay > 0 ) { szDate[ 0 ] = ( ( iYear % 10000 ) / 1000 ) + '0'; szDate[ 1 ] = ( ( iYear % 1000 ) / 100 ) + '0'; szDate[ 2 ] = ( ( iYear % 100 ) / 10 ) + '0'; szDate[ 3 ] = ( iYear % 10 ) + '0'; szDate[ 4 ] = ( iMonth / 10 ) + '0'; szDate[ 5 ] = ( iMonth % 10 ) + '0'; szDate[ 6 ] = ( iDay / 10 ) + '0'; szDate[ 7 ] = ( iDay % 10 ) + '0'; } else { memset( szDate, '0', 8 ); } } HB_EXPORT void hb_dateStrGet( const char * szDate, int * piYear, int * piMonth, int * piDay ) { HB_TRACE(HB_TR_DEBUG, ("hb_dateStrGet(%s, %p, %p, %p)", szDate, piYear, piMonth, piDay)); if( szDate && szDate[ 8 ] == '\0' ) { /* Date string has correct length, so attempt to convert */ *piYear = ( ( USHORT ) ( szDate[ 0 ] - '0' ) * 1000 ) + ( ( USHORT ) ( szDate[ 1 ] - '0' ) * 100 ) + ( ( USHORT ) ( szDate[ 2 ] - '0' ) * 10 ) + ( USHORT ) ( szDate[ 3 ] - '0' ); *piMonth = ( ( szDate[ 4 ] - '0' ) * 10 ) + ( szDate[ 5 ] - '0' ); *piDay = ( ( szDate[ 6 ] - '0' ) * 10 ) + ( szDate[ 7 ] - '0' ); } else { /* Date string missing or bad length, so force an empty date */ *piYear = *piMonth = *piDay = 0; } } HB_EXPORT int hb_dateJulianDOW( LONG lJulian ) { HB_TRACE(HB_TR_DEBUG, ("hb_dateJulianDOW(%ld)", lJulian)); if( lJulian >= HB_STR_DATE_BASE ) return ( int ) ( ( lJulian + 1 ) % 7 ) + 1; else return 0; } HB_EXPORT int hb_dateDOW( int iYear, int iMonth, int iDay ) { HB_TRACE(HB_TR_DEBUG, ("hb_dateDOW(%d, %d, %d)", iYear, iMonth, iDay)); if( iMonth < 3 ) { iMonth += 13; iYear--; } else iMonth++; return ( iDay + 26 * iMonth / 10 + iYear + iYear / 4 - iYear / 100 + iYear / 400 + 6 ) % 7 + 1; } /* This function always closes the date with a zero byte, so it needs a 9 character long buffer. */ HB_EXPORT char * hb_dateDecStr( char * szDate, LONG lJulian ) { int iYear, iMonth, iDay; HB_TRACE(HB_TR_DEBUG, ("hb_dateDecStr(%p, %ld)", szDate, lJulian)); if( lJulian == 0 ) { memset( szDate, ' ', 8 ); } else { hb_dateDecode( lJulian, &iYear, &iMonth, &iDay ); hb_dateStrPut( szDate, iYear, iMonth, iDay ); } szDate[ 8 ] = '\0'; return szDate; } HB_EXPORT LONG hb_dateEncStr( const char * szDate ) { int iYear, iMonth, iDay; HB_TRACE(HB_TR_DEBUG, ("hb_dateEncStr(%s)", szDate)); hb_dateStrGet( szDate, &iYear, &iMonth, &iDay ); return hb_dateEncode( iYear, iMonth, iDay ); }