Find wp-config.php in your PHP

// Find wp-config.php
for ( $i = 0; $i < $depth = 10; $i++ ) {
	$path = str_repeat( '../', $i );

	if ( file_exists( $path . 'wp-config.php' ) ) {
		require_once( $path . 'wp-config.php' );
		break;
	}
}

// v2

define('SHORTINIT', true);

// Find wp-config.php
$subdirectory = 'wp/';

for ( $i = 0; $i < $depth = 10; $i++ ) {
	$path = str_repeat( '../', $i );
	$dir = rtrim(realpath($path . $subdirectory), '/');

	if ( file_exists( $dir . '/wp-load.php' ) ) {
		require_once( $dir . '/wp-config.php' );
		break;
	} else if ( file_exists( $dir . '/../wp-config.php' ) ) {
		require_once( $dir . '/../wp-config.php' );
		break;
	}
}

// find wp-load.php
// Find wp-load.php
$subdirectory = 'wp/';

for ( $i = 0; $i < $depth = 10; $i++ ) {
	$path = str_repeat( '../', $i );
	$dir = rtrim(realpath($path . $subdirectory), '/');

	if ( file_exists( $dir . '/wp-load.php' ) ) {
		require_once( $dir . '/wp-load.php' );
		break;
	}
}