byte_safe_strings.php (5973B)
1 <?php 2 /** 3 * Random_* Compatibility Library 4 * for using the new PHP 7 random_* API in PHP 5 projects 5 * 6 * The MIT License (MIT) 7 * 8 * Copyright (c) 2015 - 2017 Paragon Initiative Enterprises 9 * 10 * Permission is hereby granted, free of charge, to any person obtaining a copy 11 * of this software and associated documentation files (the "Software"), to deal 12 * in the Software without restriction, including without limitation the rights 13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 14 * copies of the Software, and to permit persons to whom the Software is 15 * furnished to do so, subject to the following conditions: 16 * 17 * The above copyright notice and this permission notice shall be included in 18 * all copies or substantial portions of the Software. 19 * 20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 23 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 26 * SOFTWARE. 27 */ 28 29 if (!is_callable('RandomCompat_strlen')) { 30 if ( 31 defined('MB_OVERLOAD_STRING') && 32 ini_get('mbstring.func_overload') & MB_OVERLOAD_STRING 33 ) { 34 /** 35 * strlen() implementation that isn't brittle to mbstring.func_overload 36 * 37 * This version uses mb_strlen() in '8bit' mode to treat strings as raw 38 * binary rather than UTF-8, ISO-8859-1, etc 39 * 40 * @param string $binary_string 41 * 42 * @throws TypeError 43 * 44 * @return int 45 */ 46 function RandomCompat_strlen($binary_string) 47 { 48 if (!is_string($binary_string)) { 49 throw new TypeError( 50 'RandomCompat_strlen() expects a string' 51 ); 52 } 53 54 return (int) mb_strlen($binary_string, '8bit'); 55 } 56 57 } else { 58 /** 59 * strlen() implementation that isn't brittle to mbstring.func_overload 60 * 61 * This version just used the default strlen() 62 * 63 * @param string $binary_string 64 * 65 * @throws TypeError 66 * 67 * @return int 68 */ 69 function RandomCompat_strlen($binary_string) 70 { 71 if (!is_string($binary_string)) { 72 throw new TypeError( 73 'RandomCompat_strlen() expects a string' 74 ); 75 } 76 return (int) strlen($binary_string); 77 } 78 } 79 } 80 81 if (!is_callable('RandomCompat_substr')) { 82 83 if ( 84 defined('MB_OVERLOAD_STRING') 85 && 86 ini_get('mbstring.func_overload') & MB_OVERLOAD_STRING 87 ) { 88 /** 89 * substr() implementation that isn't brittle to mbstring.func_overload 90 * 91 * This version uses mb_substr() in '8bit' mode to treat strings as raw 92 * binary rather than UTF-8, ISO-8859-1, etc 93 * 94 * @param string $binary_string 95 * @param int $start 96 * @param int $length (optional) 97 * 98 * @throws TypeError 99 * 100 * @return string 101 */ 102 function RandomCompat_substr($binary_string, $start, $length = null) 103 { 104 if (!is_string($binary_string)) { 105 throw new TypeError( 106 'RandomCompat_substr(): First argument should be a string' 107 ); 108 } 109 110 if (!is_int($start)) { 111 throw new TypeError( 112 'RandomCompat_substr(): Second argument should be an integer' 113 ); 114 } 115 116 if ($length === null) { 117 /** 118 * mb_substr($str, 0, NULL, '8bit') returns an empty string on 119 * PHP 5.3, so we have to find the length ourselves. 120 */ 121 $length = RandomCompat_strlen($binary_string) - $start; 122 } elseif (!is_int($length)) { 123 throw new TypeError( 124 'RandomCompat_substr(): Third argument should be an integer, or omitted' 125 ); 126 } 127 128 // Consistency with PHP's behavior 129 if ($start === RandomCompat_strlen($binary_string) && $length === 0) { 130 return ''; 131 } 132 if ($start > RandomCompat_strlen($binary_string)) { 133 return ''; 134 } 135 136 return (string) mb_substr($binary_string, $start, $length, '8bit'); 137 } 138 139 } else { 140 141 /** 142 * substr() implementation that isn't brittle to mbstring.func_overload 143 * 144 * This version just uses the default substr() 145 * 146 * @param string $binary_string 147 * @param int $start 148 * @param int $length (optional) 149 * 150 * @throws TypeError 151 * 152 * @return string 153 */ 154 function RandomCompat_substr($binary_string, $start, $length = null) 155 { 156 if (!is_string($binary_string)) { 157 throw new TypeError( 158 'RandomCompat_substr(): First argument should be a string' 159 ); 160 } 161 162 if (!is_int($start)) { 163 throw new TypeError( 164 'RandomCompat_substr(): Second argument should be an integer' 165 ); 166 } 167 168 if ($length !== null) { 169 if (!is_int($length)) { 170 throw new TypeError( 171 'RandomCompat_substr(): Third argument should be an integer, or omitted' 172 ); 173 } 174 175 return (string) substr($binary_string, $start, $length); 176 } 177 178 return (string) substr($binary_string, $start); 179 } 180 } 181 }