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| Direktori : /www/varak.net/wiki.varak.net/vendor/wikimedia/base-convert/src/ |
| Current File : /www/varak.net/wiki.varak.net/vendor/wikimedia/base-convert/src/Functions.php |
<?php
/**
* 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.
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
*/
namespace Wikimedia;
/**
* Convert an arbitrarily-long string from one numeric base to
* another, optionally zero-padding to a minimum column width.
*
* Supports base 2 through 36; digit values 10-36 are represented
* as lowercase letters a-z. Input is case-insensitive.
*
* @param string $input Input number
* @param int $sourceBase Base of the input number
* @param int $destBase Desired base of the output
* @param int $pad Minimum number of digits in the output (pad with zeroes)
* @param bool $lowercase Whether to output in lowercase or uppercase
* @param string $engine Either "gmp", "bcmath", or "php"
* @return string|bool The output number as a string, or false on error
*/
function base_convert( $input, $sourceBase, $destBase, $pad = 1,
$lowercase = true, $engine = 'auto'
) {
$input = (string)$input;
if (
$sourceBase < 2 ||
$sourceBase > 36 ||
$destBase < 2 ||
$destBase > 36 ||
$sourceBase != (int)$sourceBase ||
$destBase != (int)$destBase ||
$pad != (int)$pad ||
!preg_match(
"/^[" . substr( '0123456789abcdefghijklmnopqrstuvwxyz', 0, $sourceBase ) . "]+$/i",
$input
)
) {
return false;
}
static $baseChars = [
10 => 'a', 11 => 'b', 12 => 'c', 13 => 'd', 14 => 'e', 15 => 'f',
16 => 'g', 17 => 'h', 18 => 'i', 19 => 'j', 20 => 'k', 21 => 'l',
22 => 'm', 23 => 'n', 24 => 'o', 25 => 'p', 26 => 'q', 27 => 'r',
28 => 's', 29 => 't', 30 => 'u', 31 => 'v', 32 => 'w', 33 => 'x',
34 => 'y', 35 => 'z',
'0' => 0, '1' => 1, '2' => 2, '3' => 3, '4' => 4, '5' => 5,
'6' => 6, '7' => 7, '8' => 8, '9' => 9, 'a' => 10, 'b' => 11,
'c' => 12, 'd' => 13, 'e' => 14, 'f' => 15, 'g' => 16, 'h' => 17,
'i' => 18, 'j' => 19, 'k' => 20, 'l' => 21, 'm' => 22, 'n' => 23,
'o' => 24, 'p' => 25, 'q' => 26, 'r' => 27, 's' => 28, 't' => 29,
'u' => 30, 'v' => 31, 'w' => 32, 'x' => 33, 'y' => 34, 'z' => 35
];
if ( extension_loaded( 'gmp' ) && ( $engine == 'auto' || $engine == 'gmp' ) ) {
// Removing leading zeros works around broken base detection code in
// some PHP versions (see <https://bugs.php.net/bug.php?id=50175> and
// <https://bugs.php.net/bug.php?id=55398>).
$result = gmp_strval( gmp_init( ltrim( $input, '0' ) ?: '0', $sourceBase ), $destBase );
} elseif ( extension_loaded( 'bcmath' ) && ( $engine == 'auto' || $engine == 'bcmath' ) ) {
$decimal = '0';
foreach ( str_split( strtolower( $input ) ) as $char ) {
$decimal = bcmul( $decimal, $sourceBase );
$decimal = bcadd( $decimal, $baseChars[$char] );
}
// @codingStandardsIgnoreStart Generic.CodeAnalysis.ForLoopWithTestFunctionCall.NotAllowed
for ( $result = ''; bccomp( $decimal, 0 ); $decimal = bcdiv( $decimal, $destBase, 0 ) ) {
// As of PHP 7.2, bcmod can return a floating point value if bcscale is nonzero
$result .= $baseChars[(int)bcmod( $decimal, $destBase )];
}
// @codingStandardsIgnoreEnd
$result = strrev( $result );
} else {
$inDigits = [];
foreach ( str_split( strtolower( $input ) ) as $char ) {
$inDigits[] = $baseChars[$char];
}
// Iterate over the input, modulo-ing out an output digit
// at a time until input is gone.
$result = '';
while ( $inDigits ) {
$work = 0;
$workDigits = [];
// Long division...
foreach ( $inDigits as $digit ) {
$work *= $sourceBase;
$work += $digit;
if ( $workDigits || $work >= $destBase ) {
$workDigits[] = (int)( $work / $destBase );
}
$work %= $destBase;
}
// All that division leaves us with a remainder,
// which is conveniently our next output digit.
$result .= $baseChars[$work];
// And we continue!
$inDigits = $workDigits;
}
$result = strrev( $result );
}
if ( !$lowercase ) {
$result = strtoupper( $result );
}
return str_pad( $result, $pad, '0', STR_PAD_LEFT );
}