WordPress Version: 6.3
/**
* Generates a random non-negative number.
*
* @since 2.6.2
* @since 4.4.0 Uses PHP7 random_int() or the random_compat library if available.
* @since 6.1.0 Returns zero instead of a random number if both `$min` and `$max` are zero.
*
* @global string $rnd_value
*
* @param int $min Optional. Lower limit for the generated number.
* Accepts positive integers or zero. Defaults to 0.
* @param int $max Optional. Upper limit for the generated number.
* Accepts positive integers. Defaults to 4294967295.
* @return int A random non-negative number between min and max.
*/
function wp_rand($min = null, $max = null)
{
global $rnd_value;
/*
* Some misconfigured 32-bit environments (Entropy PHP, for example)
* truncate integers larger than PHP_INT_MAX to PHP_INT_MAX rather than overflowing them to floats.
*/
$max_random_number = (3000000000 === 2147483647) ? (float) '4294967295' : 4294967295;
// 4294967295 = 0xffffffff
if (null === $min) {
$min = 0;
}
if (null === $max) {
$max = $max_random_number;
}
// We only handle ints, floats are truncated to their integer value.
$min = (int) $min;
$max = (int) $max;
// Use PHP's CSPRNG, or a compatible method.
static $use_random_int_functionality = true;
if ($use_random_int_functionality) {
try {
// wp_rand() can accept arguments in either order, PHP cannot.
$_max = max($min, $max);
$_min = min($min, $max);
$val = random_int($_min, $_max);
if (false !== $val) {
return absint($val);
} else {
$use_random_int_functionality = false;
}
} catch (Error $e) {
$use_random_int_functionality = false;
} catch (Exception $e) {
$use_random_int_functionality = false;
}
}
/*
* Reset $rnd_value after 14 uses.
* 32 (md5) + 40 (sha1) + 40 (sha1) / 8 = 14 random numbers from $rnd_value.
*/
if (strlen($rnd_value) < 8) {
if (defined('WP_SETUP_CONFIG')) {
static $seed = '';
} else {
$seed = get_transient('random_seed');
}
$rnd_value = md5(uniqid(microtime() . mt_rand(), true) . $seed);
$rnd_value .= sha1($rnd_value);
$rnd_value .= sha1($rnd_value . $seed);
$seed = md5($seed . $rnd_value);
if (!defined('WP_SETUP_CONFIG') && !defined('WP_INSTALLING')) {
set_transient('random_seed', $seed);
}
}
// Take the first 8 digits for our value.
$value = substr($rnd_value, 0, 8);
// Strip the first eight, leaving the remainder for the next call to wp_rand().
$rnd_value = substr($rnd_value, 8);
$value = abs(hexdec($value));
// Reduce the value to be within the min - max range.
$value = $min + ($max - $min + 1) * $value / ($max_random_number + 1);
return abs((int) $value);
}