<?php
namespace PhpZip\Util;
use PhpZip\Exception\ZipException;
/**
* Convert unix timestamp values to DOS date/time values and vice versa.
*
* @author Ne-Lexa [email protected]
* @license MIT
*/
class DateTimeConverter
{
/**
* Smallest supported DOS date/time value in a ZIP file,
* which is January 1st, 1980 AD 00:00:00 local time.
*/
const MIN_DOS_TIME = 0x210000; // (1 << 21) | (1 << 16)
/**
* Largest supported DOS date/time value in a ZIP file,
* which is December 31st, 2107 AD 23:59:58 local time.
*/
const MAX_DOS_TIME = 0xff9fbf7d; // ((2107 - 1980) << 25) | (12 << 21) | (31 << 16) | (23 << 11) | (59 << 5) | (58 >> 1);
/**
* Convert a 32 bit integer DOS date/time value to a UNIX timestamp value.
*
* @param int $dosTime Dos date/time
*
* @return int Unix timestamp
*/
public static function toUnixTimestamp($dosTime)
{
if ($dosTime < self::MIN_DOS_TIME) {
$dosTime = self::MIN_DOS_TIME;
} elseif ($dosTime > self::MAX_DOS_TIME) {
$dosTime = self::MAX_DOS_TIME;
}
return mktime(
($dosTime >> 11) & 0x1f, // hour
($dosTime >> 5) & 0x3f, // minute
2 * ($dosTime & 0x1f), // second
($dosTime >> 21) & 0x0f, // month
($dosTime >> 16) & 0x1f, // day
1980 + (($dosTime >> 25) & 0x7f) // year
);
}
/**
* Converts a UNIX timestamp value to a DOS date/time value.
*
* @param int $unixTimestamp the number of seconds since midnight, January 1st,
* 1970 AD UTC
*
* @throws ZipException if unix timestamp is negative
*
* @return int a DOS date/time value reflecting the local time zone and
* rounded down to even seconds
* and is in between DateTimeConverter::MIN_DOS_TIME and DateTimeConverter::MAX_DOS_TIME
*/
public static function toDosTime($unixTimestamp)
{
if ($unixTimestamp < 0) {
throw new ZipException('Negative unix timestamp: ' . $unixTimestamp);
}
$date = getdate($unixTimestamp);
if ($date['year'] < 1980) {
return self::MIN_DOS_TIME;
}
$date['year'] -= 1980;
return $date['year'] << 25 | $date['mon'] << 21 |
$date['mday'] << 16 | $date['hours'] << 11 |
$date['minutes'] << 5 | $date['seconds'] >> 1;
}
}