php websocket握手

Question

我使用此代码与客户端进行握手，但在浏览器中，我遇到了这个问题：

状态行不以CRLF结尾

您可以看到\r\n\r\n在行尾使用，但它仍无效。问题在哪里？

function handshake($client, $headers) {

    //$this->console("Getting client WebSocket version...");
    if (preg_match("/Sec-WebSocket-Version: (.*)\r\n/", $headers, $match))
        $version = $match[1];
    else {
        echo "The client doesn't support WebSocket";
        return false;
    }

    //$this->console("Client WebSocket version is {$version}, (required: 13)");
    if ($version == 13) {
        // Extract header variables
        echo "Getting headers...";
        if (preg_match("/GET (.*) HTTP/", $headers, $match))
            $root = $match[1];
        if (preg_match("/Host: (.*)\r\n/", $headers, $match))
            $host = $match[1];
        if (preg_match("/Origin: (.*)\r\n/", $headers, $match))
            $origin = $match[1];
        if (preg_match("/Sec-WebSocket-Key: (.*)\r\n/", $headers, $match))
            $key = $match[1];

        echo "Client headers are:";
        echo"\t- Root: " . $root;
        echo"\t- Host: " . $host;
        echo"\t- Origin: " . $origin;
        echo"\t- Sec-WebSocket-Key: " . $key;

        echo "Generating Sec-WebSocket-Accept key...";
        $acceptKey = $key . '258EAFA5-E914-47DA-95CA-C5AB0DC85B11';
        $acceptKey = base64_encode(sha1($acceptKey, true));

        $upgrade = "HTTP/1.1 101 Switching Protocols\r\n" .
                "Upgrade: websocket\r\n" .
                "Connection: Upgrade\r\n" .
                "Sec-WebSocket-Accept: $acceptKey" .
                "\r\n\r\n";

        echo "Sending this response to the client"
        . "\r\n" . $upgrade
        ;
        socket_write($client, $upgrade);
        //$client->setHandshake(true);
        echo "Handshake is successfully done!";
        return true;
    }
    else {
        echo
        "WebSocket version 13 required"
        . "(the client supports version {$version})"
        ;
        return false;
    }
}