wp/wp-includes/random_compat/random_int.php
changeset 9 177826044cd9
parent 7 cf61fcea0001
child 19 3d72ae0968f4
--- a/wp/wp-includes/random_compat/random_int.php	Mon Oct 14 18:06:33 2019 +0200
+++ b/wp/wp-includes/random_compat/random_int.php	Mon Oct 14 18:28:13 2019 +0200
@@ -1,193 +1,190 @@
 <?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 ( ! is_callable( 'random_int' ) ):
-/**
- * Fetch a random integer between $min and $max inclusive
- * 
- * @param int $min
- * @param int $max
- * 
- * @throws Exception
- * 
- * @return int
- */
-function random_int($min, $max)
-{
+if (!is_callable('random_int')) {
     /**
-     * Type and input logic checks
-     * 
-     * If you pass it a float in the range (~PHP_INT_MAX, PHP_INT_MAX)
-     * (non-inclusive), it will sanely cast it to an int. If you it's equal to
-     * ~PHP_INT_MAX or PHP_INT_MAX, we let it fail as not an integer. Floats 
-     * lose precision, so the <= and => operators might accidentally let a float
-     * through.
+     * Random_* Compatibility Library
+     * for using the new PHP 7 random_* API in PHP 5 projects
+     *
+     * The MIT License (MIT)
+     *
+     * Copyright (c) 2015 - 2017 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.
      */
-    
-    try {
-        $min = RandomCompat_intval($min);
-    } catch (TypeError $ex) {
-        throw new TypeError(
-            'random_int(): $min must be an integer'
-        );
-    }
-
-    try {
-        $max = RandomCompat_intval($max);
-    } catch (TypeError $ex) {
-        throw new TypeError(
-            'random_int(): $max must be an integer'
-        );
-    }
-    
-    /**
-     * Now that we've verified our weak typing system has given us an integer,
-     * let's validate the logic then we can move forward with generating random
-     * integers along a given range.
-     */
-    if ($min > $max) {
-        throw new Error(
-            'Minimum value must be less than or equal to the maximum value'
-        );
-    }
-
-    if ($max === $min) {
-        return $min;
-    }
 
     /**
-     * Initialize variables to 0
-     * 
-     * We want to store:
-     * $bytes => the number of random bytes we need
-     * $mask => an integer bitmask (for use with the &) operator
-     *          so we can minimize the number of discards
-     */
-    $attempts = $bits = $bytes = $mask = $valueShift = 0;
-
-    /**
-     * At this point, $range is a positive number greater than 0. It might
-     * overflow, however, if $max - $min > PHP_INT_MAX. PHP will cast it to
-     * a float and we will lose some precision.
+     * Fetch a random integer between $min and $max inclusive
+     *
+     * @param int $min
+     * @param int $max
+     *
+     * @throws Exception
+     *
+     * @return int
      */
-    $range = $max - $min;
-
-    /**
-     * Test for integer overflow:
-     */
-    if (!is_int($range)) {
-
+    function random_int($min, $max)
+    {
         /**
-         * Still safely calculate wider ranges.
-         * Provided by @CodesInChaos, @oittaa
-         * 
-         * @ref https://gist.github.com/CodesInChaos/03f9ea0b58e8b2b8d435
-         * 
-         * We use ~0 as a mask in this case because it generates all 1s
-         * 
-         * @ref https://eval.in/400356 (32-bit)
-         * @ref http://3v4l.org/XX9r5  (64-bit)
+         * Type and input logic checks
+         *
+         * If you pass it a float in the range (~PHP_INT_MAX, PHP_INT_MAX)
+         * (non-inclusive), it will sanely cast it to an int. If you it's equal to
+         * ~PHP_INT_MAX or PHP_INT_MAX, we let it fail as not an integer. Floats
+         * lose precision, so the <= and => operators might accidentally let a float
+         * through.
          */
-        $bytes = PHP_INT_SIZE;
-        $mask = ~0;
-
-    } else {
 
-        /**
-         * $bits is effectively ceil(log($range, 2)) without dealing with 
-         * type juggling
-         */
-        while ($range > 0) {
-            if ($bits % 8 === 0) {
-               ++$bytes;
-            }
-            ++$bits;
-            $range >>= 1;
-            $mask = $mask << 1 | 1;
+        try {
+            $min = RandomCompat_intval($min);
+        } catch (TypeError $ex) {
+            throw new TypeError(
+                'random_int(): $min must be an integer'
+            );
         }
-        $valueShift = $min;
-    }
 
-    /**
-     * Now that we have our parameters set up, let's begin generating
-     * random integers until one falls between $min and $max
-     */
-    do {
-        /**
-         * The rejection probability is at most 0.5, so this corresponds
-         * to a failure probability of 2^-128 for a working RNG
-         */
-        if ($attempts > 128) {
-            throw new Exception(
-                'random_int: RNG is broken - too many rejections'
+        try {
+            $max = RandomCompat_intval($max);
+        } catch (TypeError $ex) {
+            throw new TypeError(
+                'random_int(): $max must be an integer'
             );
         }
 
         /**
-         * Let's grab the necessary number of random bytes
+         * Now that we've verified our weak typing system has given us an integer,
+         * let's validate the logic then we can move forward with generating random
+         * integers along a given range.
          */
-        $randomByteString = random_bytes($bytes);
-        if ($randomByteString === false) {
-            throw new Exception(
-                'Random number generator failure'
+        if ($min > $max) {
+            throw new Error(
+                'Minimum value must be less than or equal to the maximum value'
             );
         }
 
+        if ($max === $min) {
+            return (int) $min;
+        }
+
         /**
-         * Let's turn $randomByteString into an integer
-         * 
-         * This uses bitwise operators (<< and |) to build an integer
-         * out of the values extracted from ord()
-         * 
-         * Example: [9F] | [6D] | [32] | [0C] =>
-         *   159 + 27904 + 3276800 + 201326592 =>
-         *   204631455
+         * Initialize variables to 0
+         *
+         * We want to store:
+         * $bytes => the number of random bytes we need
+         * $mask => an integer bitmask (for use with the &) operator
+         *          so we can minimize the number of discards
          */
-        $val = 0;
-        for ($i = 0; $i < $bytes; ++$i) {
-            $val |= ord($randomByteString[$i]) << ($i * 8);
-        }
+        $attempts = $bits = $bytes = $mask = $valueShift = 0;
+
+        /**
+         * At this point, $range is a positive number greater than 0. It might
+         * overflow, however, if $max - $min > PHP_INT_MAX. PHP will cast it to
+         * a float and we will lose some precision.
+         */
+        $range = $max - $min;
 
         /**
-         * Apply mask
+         * Test for integer overflow:
          */
-        $val &= $mask;
-        $val += $valueShift;
+        if (!is_int($range)) {
+
+            /**
+             * Still safely calculate wider ranges.
+             * Provided by @CodesInChaos, @oittaa
+             *
+             * @ref https://gist.github.com/CodesInChaos/03f9ea0b58e8b2b8d435
+             *
+             * We use ~0 as a mask in this case because it generates all 1s
+             *
+             * @ref https://eval.in/400356 (32-bit)
+             * @ref http://3v4l.org/XX9r5  (64-bit)
+             */
+            $bytes = PHP_INT_SIZE;
+            $mask = ~0;
 
-        ++$attempts;
+        } else {
+
+            /**
+             * $bits is effectively ceil(log($range, 2)) without dealing with
+             * type juggling
+             */
+            while ($range > 0) {
+                if ($bits % 8 === 0) {
+                    ++$bytes;
+                }
+                ++$bits;
+                $range >>= 1;
+                $mask = $mask << 1 | 1;
+            }
+            $valueShift = $min;
+        }
+
+        $val = 0;
         /**
-         * If $val overflows to a floating point number,
-         * ... or is larger than $max,
-         * ... or smaller than $min,
-         * then try again.
+         * Now that we have our parameters set up, let's begin generating
+         * random integers until one falls between $min and $max
          */
-    } while (!is_int($val) || $val > $max || $val < $min);
+        do {
+            /**
+             * The rejection probability is at most 0.5, so this corresponds
+             * to a failure probability of 2^-128 for a working RNG
+             */
+            if ($attempts > 128) {
+                throw new Exception(
+                    'random_int: RNG is broken - too many rejections'
+                );
+            }
+
+            /**
+             * Let's grab the necessary number of random bytes
+             */
+            $randomByteString = random_bytes($bytes);
 
-    return (int) $val;
+            /**
+             * Let's turn $randomByteString into an integer
+             *
+             * This uses bitwise operators (<< and |) to build an integer
+             * out of the values extracted from ord()
+             *
+             * Example: [9F] | [6D] | [32] | [0C] =>
+             *   159 + 27904 + 3276800 + 201326592 =>
+             *   204631455
+             */
+            $val &= 0;
+            for ($i = 0; $i < $bytes; ++$i) {
+                $val |= ord($randomByteString[$i]) << ($i * 8);
+            }
+
+            /**
+             * Apply mask
+             */
+            $val &= $mask;
+            $val += $valueShift;
+
+            ++$attempts;
+            /**
+             * If $val overflows to a floating point number,
+             * ... or is larger than $max,
+             * ... or smaller than $min,
+             * then try again.
+             */
+        } while (!is_int($val) || $val > $max || $val < $min);
+
+        return (int) $val;
+    }
 }
-endif;