minivmac4ios/Mini vMac/mnvm_core/DATE2SEC.h
2016-05-01 19:05:36 +02:00

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/*
DATE2SEC.h
Copyright (C) 2003 Bradford L. Barrett, Paul C. Pratt
You can redistribute this file and/or modify it under the terms
of version 2 of the GNU General Public License as published by
the Free Software Foundation. You should have received a copy
of the license along with this file; see the file COPYING.
This file 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
license for more details.
*/
/*
DATE 2(to) SEConds
convert year/month/day/hour/minute/second
to number of seconds since the beginning
of 1904, the format for storing dates
on the Macintosh.
The function jdate is from the program Webalizer
by Bradford L. Barrett.
*/
#ifdef DATE2SEC_H
#error "header already included"
#else
#define DATE2SEC_H
#endif
/*
The function jdate was found at the end of the file
webalizer.c in the program webalizer at
"www.mrunix.net/webalizer/".
Here is copyright info from the top of that file:
webalizer - a web server log analysis program
Copyright (C) 1997-2000 Bradford L. Barrett (brad@mrunix.net)
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 of the License, or
(at your option) any later version, and provided that the above
copyright and permission notice is included with all distributed
copies of this or derived software.
*/
/* ************************************************************* */
/* */
/* JDATE - Julian date calculator */
/* */
/* Calculates the number of days since Jan 1, 0000. */
/* */
/* Originally written by Bradford L. Barrett (03/17/1988) */
/* Returns an unsigned long value representing the number of */
/* days since January 1, 0000. */
/* */
/* Note: Due to the changes made by Pope Gregory XIII in the */
/* 16th Centyry (Feb 24, 1582), dates before 1583 will */
/* not return a truely accurate number (will be at least */
/* 10 days off). Somehow, I don't think this will */
/* present much of a problem for most situations :) */
/* */
/* Usage: days = jdate(day, month, year) */
/* */
/* The number returned is adjusted by 5 to facilitate day of */
/* week calculations. The mod of the returned value gives the */
/* day of the week the date is. (ie: dow = days % 7) where */
/* dow will return 0=Sunday, 1=Monday, 2=Tuesday, etc... */
/* */
/* ************************************************************* */
LOCALFUNC ui5b jdate(int day, int month, int year)
{
ui5b days; /* value returned */
int mtable[] = {
0, 31, 59, 90, 120, 151,
181, 212, 243, 273, 304, 334
};
/*
First, calculate base number including leap
and Centenial year stuff
*/
days = (((ui5b)year * 365) + day + mtable[month - 1]
+ ((year + 4) / 4) - ((year / 100) - (year / 400)));
/* now adjust for leap year before March 1st */
if ((year % 4 == 0)
&& (! ((year % 100 == 0) && (year % 400 != 0)))
&& (month < 3))
{
--days;
}
/* done, return with calculated value */
return (days + 5);
}
LOCALFUNC ui5b Date2MacSeconds(int second, int minute, int hour,
int day, int month, int year)
{
ui5b curjdate;
ui5b basejdate;
curjdate = jdate(day, month, year);
basejdate = jdate(1, 1, 1904);
return (((curjdate - basejdate) * 24 + hour) * 60
+ minute) * 60 + second;
}