| 
<?php/**
 * Random_* Compatibility Library
 * for using the new PHP 7 random_* API in PHP 5 projects
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2015 Paragon Initiative Enterprises
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
 
 /**
 * If the libsodium PHP extension is loaded, we'll use it above any other
 * solution.
 *
 * libsodium-php project:
 * @ref https://github.com/jedisct1/libsodium-php
 *
 * @param int $bytes
 *
 * @throws Exception
 *
 * @return string
 */
 function random_bytes($bytes)
 {
 try {
 $bytes = RandomCompat_intval($bytes);
 } catch (TypeError $ex) {
 throw new TypeError(
 'random_bytes(): $bytes must be an integer'
 );
 }
 if ($bytes < 1) {
 throw new Error(
 'Length must be greater than 0'
 );
 }
 /**
 * \Sodium\randombytes_buf() doesn't allow more than 2147483647 bytes to be
 * generated in one invocation.
 */
 if ($bytes > 2147483647) {
 $buf = '';
 for ($i = 0; $i < $bytes; $i += 1073741824) {
 $n = ($bytes - $i) > 1073741824
 ? 1073741824
 : $bytes - $i;
 $buf .= \Sodium\randombytes_buf($n);
 }
 } else {
 $buf = \Sodium\randombytes_buf($bytes);
 }
 
 if ($buf !== false) {
 if (RandomCompat_strlen($buf) === $bytes) {
 return $buf;
 }
 }
 
 /**
 * If we reach here, PHP has failed us.
 */
 throw new Exception(
 'Could not gather sufficient random data'
 );
 }
 
 |