LibWebSocket: Make WebSocketImpl an abstract class

The LibCore sockets implementation becomes WebSocketImplSerenity.
This will allow us to create a custom WebSocketImpl subclass for Qt
to use in Ladybird.

Userland/Libraries/LibWebSocket/Impl/WebSocketImplSerenity.cpp

@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2021, Dex♪ <dexes.ttp@gmail.com>
+ * Copyright (c) 2022, Ali Mohammad Pur <mpfard@serenityos.org>
+ * Copyright (c) 2022, the SerenityOS developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibCore/EventLoop.h>
+#include <LibWebSocket/Impl/WebSocketImplSerenity.h>
+
+namespace WebSocket {
+
+WebSocketImplSerenity::~WebSocketImplSerenity() = default;
+WebSocketImplSerenity::WebSocketImplSerenity() = default;
+
+bool WebSocketImplSerenity::can_read_line()
+{
+    return MUST(m_socket->can_read_line());
+}
+
+bool WebSocketImplSerenity::can_read()
+{
+    return MUST(m_socket->can_read_without_blocking());
+}
+
+bool WebSocketImplSerenity::send(ReadonlyBytes bytes)
+{
+    return m_socket->write_or_error(bytes);
+}
+
+bool WebSocketImplSerenity::eof()
+{
+    return m_socket->is_eof();
+}
+
+void WebSocketImplSerenity::discard_connection()
+{
+    m_socket = nullptr;
+}
+
+void WebSocketImplSerenity::connect(ConnectionInfo const& connection_info)
+{
+    VERIFY(!m_socket);
+    VERIFY(on_connected);
+    VERIFY(on_connection_error);
+    VERIFY(on_ready_to_read);
+    auto socket_result = [&]() -> ErrorOr<NonnullOwnPtr<Core::Stream::BufferedSocketBase>> {
+        if (connection_info.is_secure()) {
+            TLS::Options options;
+            options.set_alert_handler([this](auto) {
+                on_connection_error();
+            });
+            return TRY(Core::Stream::BufferedSocket<TLS::TLSv12>::create(
+                TRY(TLS::TLSv12::connect(connection_info.url().host(), connection_info.url().port_or_default(), move(options)))));
+        }
+
+        return TRY(Core::Stream::BufferedTCPSocket::create(
+            TRY(Core::Stream::TCPSocket::connect(connection_info.url().host(), connection_info.url().port_or_default()))));
+    }();
+
+    if (socket_result.is_error()) {
+        Core::deferred_invoke([this] {
+            on_connection_error();
+        });
+        return;
+    }
+
+    m_socket = socket_result.release_value();
+
+    m_socket->on_ready_to_read = [this] {
+        on_ready_to_read();
+    };
+
+    Core::deferred_invoke([this] {
+        on_connected();
+    });
+}
+
+ErrorOr<ByteBuffer> WebSocketImplSerenity::read(int max_size)
+{
+    auto buffer = TRY(ByteBuffer::create_uninitialized(max_size));
+    auto read_bytes = TRY(m_socket->read(buffer));
+    return buffer.slice(0, read_bytes.size());
+}
+
+ErrorOr<String> WebSocketImplSerenity::read_line(size_t size)
+{
+    auto buffer = TRY(ByteBuffer::create_uninitialized(size));
+    auto line = TRY(m_socket->read_line(buffer));
+    return line.to_string();
+}
+
+}