Chris@0: <?php
Chris@0: /**
Chris@0:  * Random_* Compatibility Library
Chris@0:  * for using the new PHP 7 random_* API in PHP 5 projects
Chris@0:  *
Chris@0:  * The MIT License (MIT)
Chris@0:  *
Chris@16:  * Copyright (c) 2015 - 2018 Paragon Initiative Enterprises
Chris@0:  *
Chris@0:  * Permission is hereby granted, free of charge, to any person obtaining a copy
Chris@0:  * of this software and associated documentation files (the "Software"), to deal
Chris@0:  * in the Software without restriction, including without limitation the rights
Chris@0:  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
Chris@0:  * copies of the Software, and to permit persons to whom the Software is
Chris@0:  * furnished to do so, subject to the following conditions:
Chris@0:  *
Chris@0:  * The above copyright notice and this permission notice shall be included in
Chris@0:  * all copies or substantial portions of the Software.
Chris@0:  *
Chris@0:  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
Chris@0:  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
Chris@0:  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
Chris@0:  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
Chris@0:  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
Chris@0:  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
Chris@0:  * SOFTWARE.
Chris@0:  */
Chris@0: 
Chris@0: if (!is_callable('RandomCompat_strlen')) {
Chris@0:     if (
Chris@16:         defined('MB_OVERLOAD_STRING')
Chris@16:             &&
Chris@16:         ((int) ini_get('mbstring.func_overload')) & MB_OVERLOAD_STRING
Chris@0:     ) {
Chris@0:         /**
Chris@0:          * strlen() implementation that isn't brittle to mbstring.func_overload
Chris@0:          *
Chris@0:          * This version uses mb_strlen() in '8bit' mode to treat strings as raw
Chris@0:          * binary rather than UTF-8, ISO-8859-1, etc
Chris@0:          *
Chris@0:          * @param string $binary_string
Chris@0:          *
Chris@0:          * @throws TypeError
Chris@0:          *
Chris@0:          * @return int
Chris@0:          */
Chris@0:         function RandomCompat_strlen($binary_string)
Chris@0:         {
Chris@0:             if (!is_string($binary_string)) {
Chris@0:                 throw new TypeError(
Chris@0:                     'RandomCompat_strlen() expects a string'
Chris@0:                 );
Chris@0:             }
Chris@0: 
Chris@0:             return (int) mb_strlen($binary_string, '8bit');
Chris@0:         }
Chris@0: 
Chris@0:     } else {
Chris@0:         /**
Chris@0:          * strlen() implementation that isn't brittle to mbstring.func_overload
Chris@0:          *
Chris@0:          * This version just used the default strlen()
Chris@0:          *
Chris@0:          * @param string $binary_string
Chris@0:          *
Chris@0:          * @throws TypeError
Chris@0:          *
Chris@0:          * @return int
Chris@0:          */
Chris@0:         function RandomCompat_strlen($binary_string)
Chris@0:         {
Chris@0:             if (!is_string($binary_string)) {
Chris@0:                 throw new TypeError(
Chris@0:                     'RandomCompat_strlen() expects a string'
Chris@0:                 );
Chris@0:             }
Chris@0:             return (int) strlen($binary_string);
Chris@0:         }
Chris@0:     }
Chris@0: }
Chris@0: 
Chris@0: if (!is_callable('RandomCompat_substr')) {
Chris@0: 
Chris@0:     if (
Chris@0:         defined('MB_OVERLOAD_STRING')
Chris@16:             &&
Chris@16:         ((int) ini_get('mbstring.func_overload')) & MB_OVERLOAD_STRING
Chris@0:     ) {
Chris@0:         /**
Chris@0:          * substr() implementation that isn't brittle to mbstring.func_overload
Chris@0:          *
Chris@0:          * This version uses mb_substr() in '8bit' mode to treat strings as raw
Chris@0:          * binary rather than UTF-8, ISO-8859-1, etc
Chris@0:          *
Chris@0:          * @param string $binary_string
Chris@0:          * @param int $start
Chris@16:          * @param int|null $length (optional)
Chris@0:          *
Chris@0:          * @throws TypeError
Chris@0:          *
Chris@0:          * @return string
Chris@0:          */
Chris@0:         function RandomCompat_substr($binary_string, $start, $length = null)
Chris@0:         {
Chris@0:             if (!is_string($binary_string)) {
Chris@0:                 throw new TypeError(
Chris@0:                     'RandomCompat_substr(): First argument should be a string'
Chris@0:                 );
Chris@0:             }
Chris@0: 
Chris@0:             if (!is_int($start)) {
Chris@0:                 throw new TypeError(
Chris@0:                     'RandomCompat_substr(): Second argument should be an integer'
Chris@0:                 );
Chris@0:             }
Chris@0: 
Chris@0:             if ($length === null) {
Chris@0:                 /**
Chris@0:                  * mb_substr($str, 0, NULL, '8bit') returns an empty string on
Chris@0:                  * PHP 5.3, so we have to find the length ourselves.
Chris@0:                  */
Chris@16:                 /** @var int $length */
Chris@0:                 $length = RandomCompat_strlen($binary_string) - $start;
Chris@0:             } elseif (!is_int($length)) {
Chris@0:                 throw new TypeError(
Chris@0:                     'RandomCompat_substr(): Third argument should be an integer, or omitted'
Chris@0:                 );
Chris@0:             }
Chris@0: 
Chris@0:             // Consistency with PHP's behavior
Chris@0:             if ($start === RandomCompat_strlen($binary_string) && $length === 0) {
Chris@0:                 return '';
Chris@0:             }
Chris@0:             if ($start > RandomCompat_strlen($binary_string)) {
Chris@0:                 return '';
Chris@0:             }
Chris@0: 
Chris@16:             return (string) mb_substr(
Chris@16:                 (string) $binary_string,
Chris@16:                 (int) $start,
Chris@16:                 (int) $length,
Chris@16:                 '8bit'
Chris@16:             );
Chris@0:         }
Chris@0: 
Chris@0:     } else {
Chris@0: 
Chris@0:         /**
Chris@0:          * substr() implementation that isn't brittle to mbstring.func_overload
Chris@0:          *
Chris@0:          * This version just uses the default substr()
Chris@0:          *
Chris@0:          * @param string $binary_string
Chris@0:          * @param int $start
Chris@16:          * @param int|null $length (optional)
Chris@0:          *
Chris@0:          * @throws TypeError
Chris@0:          *
Chris@0:          * @return string
Chris@0:          */
Chris@0:         function RandomCompat_substr($binary_string, $start, $length = null)
Chris@0:         {
Chris@0:             if (!is_string($binary_string)) {
Chris@0:                 throw new TypeError(
Chris@0:                     'RandomCompat_substr(): First argument should be a string'
Chris@0:                 );
Chris@0:             }
Chris@0: 
Chris@0:             if (!is_int($start)) {
Chris@0:                 throw new TypeError(
Chris@0:                     'RandomCompat_substr(): Second argument should be an integer'
Chris@0:                 );
Chris@0:             }
Chris@0: 
Chris@0:             if ($length !== null) {
Chris@0:                 if (!is_int($length)) {
Chris@0:                     throw new TypeError(
Chris@0:                         'RandomCompat_substr(): Third argument should be an integer, or omitted'
Chris@0:                     );
Chris@0:                 }
Chris@0: 
Chris@16:                 return (string) substr(
Chris@16:                     (string )$binary_string,
Chris@16:                     (int) $start,
Chris@16:                     (int) $length
Chris@16:                 );
Chris@0:             }
Chris@0: 
Chris@16:             return (string) substr(
Chris@16:                 (string) $binary_string,
Chris@16:                 (int) $start
Chris@16:             );
Chris@0:         }
Chris@0:     }
Chris@0: }