LibCore: Add a forward declaration header

This patch adds <LibCore/Forward.h> and uses it in various places to
shrink the header dependency graph.

AK/Forward.h

@@ -70,6 +70,9 @@ class NonnullRefPtr;
 template<typename T>
 class NonnullOwnPtr;
 
+template<typename T>
+class Optional;
+
 template<typename T>
 class RefPtr;
 
@@ -98,6 +101,7 @@ using AK::JsonObject;
 using AK::JsonValue;
 using AK::NonnullOwnPtr;
 using AK::NonnullRefPtr;
+using AK::Optional;
 using AK::OwnPtr;
 using AK::RefPtr;
 using AK::SinglyLinkedList;

AK/IntrusiveList.h

@@ -26,6 +26,8 @@
 
 #pragma once
 
+#include <AK/Assertions.h>
+
 namespace AK {
 
 class IntrusiveListNode;

AK/Optional.h

@@ -30,6 +30,8 @@
 #include <AK/Platform.h>
 #include <AK/StdLibExtras.h>
 
+namespace AK {
+
 template<typename T>
 class CONSUMABLE(unknown) alignas(T) Optional {
 public:
@@ -161,3 +163,7 @@ private:
     char m_storage[sizeof(T)];
     bool m_has_value { false };
 };
+
+}
+
+using AK::Optional;

Applications/Help/main.cpp

@@ -26,6 +26,7 @@
 
 #include "History.h"
 #include "ManualModel.h"
+#include <AK/ByteBuffer.h>
 #include <LibCore/File.h>
 #include <LibGUI/AboutDialog.h>
 #include <LibGUI/Action.h>

Applications/SystemMonitor/ProcessStacksWidget.cpp

@@ -25,6 +25,7 @@
  */
 
 #include "ProcessStacksWidget.h"
+#include <AK/ByteBuffer.h>
 #include <LibCore/File.h>
 #include <LibCore/Timer.h>
 #include <LibGUI/BoxLayout.h>

DevTools/HackStudio/Editor.cpp

@@ -26,6 +26,7 @@
 
 #include "Editor.h"
 #include "EditorWrapper.h"
+#include <AK/ByteBuffer.h>
 #include <AK/FileSystemPath.h>
 #include <LibCore/DirIterator.h>
 #include <LibCore/File.h>

DevTools/IPCCompiler/main.cpp

@@ -25,6 +25,7 @@
  */
 
 #include <AK/BufferStream.h>
+#include <AK/Function.h>
 #include <AK/HashMap.h>
 #include <AK/StringBuilder.h>
 #include <LibCore/File.h>

Libraries/LibAudio/WavLoader.cpp

@@ -25,6 +25,7 @@
  */
 
 #include <AK/BufferStream.h>
+#include <AK/OwnPtr.h>
 #include <LibAudio/WavLoader.h>
 #include <LibCore/File.h>
 #include <LibCore/IODeviceStreamReader.h>

Libraries/LibCore/Event.h

@@ -30,11 +30,10 @@
 #include <AK/String.h>
 #include <AK/Types.h>
 #include <AK/WeakPtr.h>
+#include <LibCore/Forward.h>
 
 namespace Core {
 
-class Object;
-
 class Event {
 public:
     enum Type {

Libraries/LibCore/EventLoop.cpp

@@ -24,12 +24,14 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Badge.h>
 #include <AK/IDAllocator.h>
 #include <AK/JsonObject.h>
 #include <AK/JsonValue.h>
 #include <AK/Time.h>
 #include <LibCore/Event.h>
 #include <LibCore/EventLoop.h>
+#include <LibCore/LocalServer.h>
 #include <LibCore/LocalSocket.h>
 #include <LibCore/Notifier.h>
 #include <LibCore/Object.h>
@@ -328,7 +330,7 @@ void EventLoop::post_event(Object& receiver, NonnullOwnPtr<Event>&& event)
 #ifdef CEVENTLOOP_DEBUG
     dbg() << "Core::EventLoop::post_event: {" << m_queued_events.size() << "} << receiver=" << receiver << ", event=" << event;
 #endif
-    m_queued_events.append({ receiver.make_weak_ptr(), move(event) });
+    m_queued_events.empend(receiver, move(event));
 }
 
 void EventLoop::wait_for_event(WaitMode mode)
@@ -509,4 +511,20 @@ void EventLoop::wake()
     }
 }
 
+EventLoop::QueuedEvent::QueuedEvent(Object& receiver, NonnullOwnPtr<Event> event)
+    : receiver(receiver.make_weak_ptr())
+    , event(move(event))
+{
+}
+
+EventLoop::QueuedEvent::QueuedEvent(QueuedEvent&& other)
+    : receiver(other.receiver)
+    , event(move(other.event))
+{
+}
+
+EventLoop::QueuedEvent::~QueuedEvent()
+{
+}
+
 }

Libraries/LibCore/EventLoop.h

@@ -26,23 +26,18 @@
 
 #pragma once
 
-#include <AK/Badge.h>
+#include <AK/Forward.h>
 #include <AK/HashMap.h>
 #include <AK/OwnPtr.h>
 #include <AK/Vector.h>
 #include <AK/WeakPtr.h>
-#include <LibCore/Event.h>
-#include <LibCore/LocalServer.h>
+#include <LibCore/Forward.h>
+#include <LibCore/Object.h>
 #include <LibThread/Lock.h>
-#include <sys/select.h>
 #include <sys/time.h>
-#include <time.h>
 
 namespace Core {
 
-class Object;
-class Notifier;
-
 class EventLoop {
 public:
     EventLoop();
@@ -87,6 +82,12 @@ private:
     void get_next_timer_expiration(timeval&);
 
     struct QueuedEvent {
+        AK_MAKE_NONCOPYABLE(QueuedEvent);
+    public:
+        QueuedEvent(Object& receiver, NonnullOwnPtr<Event>);
+        QueuedEvent(QueuedEvent&&);
+        ~QueuedEvent();
+
         WeakPtr<Object> receiver;
         NonnullOwnPtr<Event> event;
     };

Libraries/LibCore/Forward.h

@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+namespace Core {
+
+class ArgsParser;
+class ChildEvent;
+class ConfigFile;
+class CustomEvent;
+class DateTime;
+class DirIterator;
+class ElapsedTime;
+class Event;
+class EventLoop;
+class File;
+class HttpJob;
+class HttpRequest;
+class HttpResponse;
+class IODevice;
+class LocalServer;
+class LocalSocket;
+class MimeData;
+class NetworkJob;
+class NetworkResponse;
+class Notifier;
+class Object;
+class ProcessStatisticsReader;
+class Socket;
+class SocketAddress;
+class TCPServer;
+class TCPSocket;
+class TimerEvent;
+class UdpServer;
+class UdpSocket;
+
+enum class TimerShouldFireWhenNotVisible;
+
+}

Libraries/LibCore/IODevice.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/ByteBuffer.h>
 #include <AK/PrintfImplementation.h>
 #include <LibCore/IODevice.h>
 #include <LibCore/SyscallUtils.h>
@@ -296,4 +297,10 @@ void IODevice::set_fd(int fd)
     m_fd = fd;
     did_update_fd(fd);
 }
+
+bool IODevice::write(const StringView& v)
+{
+    return write((const u8*)v.characters_without_null_termination(), v.length());
+}
+
 }

Libraries/LibCore/IODevice.h

@@ -26,8 +26,7 @@
 
 #pragma once
 
-#include <AK/ByteBuffer.h>
-#include <AK/StringView.h>
+#include <AK/Forward.h>
 #include <LibCore/Object.h>
 
 namespace Core {
@@ -64,7 +63,7 @@ public:
     ByteBuffer read_all();
 
     bool write(const u8*, int size);
-    bool write(const StringView& v) { return write((const u8*)v.characters_without_null_termination(), v.length()); }
+    bool write(const StringView&);
 
     // FIXME: I would like this to be const but currently it needs to call populate_read_buffer().
     bool can_read_line();

Libraries/LibCore/LocalSocket.h

@@ -26,7 +26,6 @@
 
 #pragma once
 
-#include <AK/Badge.h>
 #include <LibCore/Socket.h>
 
 namespace Core {

Libraries/LibCore/Notifier.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Badge.h>
 #include <LibCore/Event.h>
 #include <LibCore/EventLoop.h>
 #include <LibCore/Notifier.h>

Libraries/LibCore/Object.h

@@ -26,19 +26,13 @@
 
 #pragma once
 
-#include <AK/Badge.h>
-#include <AK/Function.h>
+#include <AK/Forward.h>
 #include <AK/IntrusiveList.h>
 #include <AK/Noncopyable.h>
 #include <AK/NonnullRefPtrVector.h>
-#include <AK/StdLibExtras.h>
 #include <AK/String.h>
-#include <AK/Vector.h>
 #include <AK/Weakable.h>
-
-namespace AK {
-class JsonObject;
-}
+#include <LibCore/Forward.h>
 
 namespace Core {
 
@@ -47,12 +41,6 @@ enum class TimerShouldFireWhenNotVisible {
     Yes
 };
 
-class ChildEvent;
-class CustomEvent;
-class Event;
-class EventLoop;
-class TimerEvent;
-
 #define C_OBJECT(klass)                                                \
 public:                                                                \
     virtual const char* class_name() const override { return #klass; } \

Libraries/LibCore/Socket.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/ByteBuffer.h>
 #include <LibCore/Notifier.h>
 #include <LibCore/Socket.h>
 #include <arpa/inet.h>

Libraries/LibCore/Socket.h

@@ -26,6 +26,7 @@
 
 #pragma once
 
+#include <AK/Function.h>
 #include <LibCore/IODevice.h>
 #include <LibCore/SocketAddress.h>
 

Libraries/LibCore/UdpServer.h

@@ -26,14 +26,13 @@
 
 #pragma once
 
-#include <AK/IPv4Address.h>
-#include <LibCore/Notifier.h>
+#include <AK/Forward.h>
+#include <AK/Function.h>
+#include <LibCore/Forward.h>
 #include <LibCore/Object.h>
 
 namespace Core {
 
-class UdpSocket;
-
 class UdpServer : public Object {
     C_OBJECT(UdpServer)
 public:

Libraries/LibCore/UdpSocket.h

@@ -26,7 +26,6 @@
 
 #pragma once
 
-#include <AK/Badge.h>
 #include <LibCore/Socket.h>
 
 namespace Core {

Libraries/LibGUI/DragOperation.cpp

@@ -24,9 +24,10 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <LibGfx/Bitmap.h>
+#include <AK/Badge.h>
 #include <LibGUI/DragOperation.h>
 #include <LibGUI/WindowServerConnection.h>
+#include <LibGfx/Bitmap.h>
 
 namespace GUI {
 

Libraries/LibGUI/Window.h

@@ -26,14 +26,14 @@
 
 #pragma once
 
-#include <AK/Badge.h>
+#include <AK/Function.h>
 #include <AK/HashMap.h>
 #include <AK/String.h>
 #include <AK/WeakPtr.h>
 #include <LibCore/Object.h>
+#include <LibGUI/WindowType.h>
 #include <LibGfx/Bitmap.h>
 #include <LibGfx/Rect.h>
-#include <LibGUI/WindowType.h>
 
 namespace GUI {
 

Libraries/LibHTML/DOM/HTMLLinkElement.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/ByteBuffer.h>
 #include <AK/URL.h>
 #include <LibCore/File.h>
 #include <LibHTML/DOM/Document.h>

Libraries/LibIPC/ClientConnection.h

@@ -26,6 +26,7 @@
 
 #pragma once
 
+#include <AK/ByteBuffer.h>
 #include <LibCore/Event.h>
 #include <LibCore/EventLoop.h>
 #include <LibCore/IODevice.h>

Libraries/LibIPC/ServerConnection.h

@@ -26,6 +26,7 @@
 
 #pragma once
 
+#include <AK/ByteBuffer.h>
 #include <AK/NonnullOwnPtrVector.h>
 #include <LibCore/Event.h>
 #include <LibCore/EventLoop.h>

Libraries/LibThread/BackgroundAction.h

@@ -30,6 +30,7 @@
 #include <AK/NonnullRefPtr.h>
 #include <AK/Optional.h>
 #include <AK/Queue.h>
+#include <LibCore/Event.h>
 #include <LibCore/EventLoop.h>
 #include <LibCore/Object.h>
 #include <LibThread/Lock.h>

Servers/AudioServer/ASMixer.h

@@ -27,6 +27,7 @@
 #pragma once
 
 #include "ASClientConnection.h"
+#include <AK/Badge.h>
 #include <AK/ByteBuffer.h>
 #include <AK/NonnullRefPtrVector.h>
 #include <AK/Queue.h>

Servers/LookupServer/main.cpp

@@ -26,6 +26,7 @@
 
 #include "LookupServer.h"
 #include <LibCore/EventLoop.h>
+#include <LibCore/LocalServer.h>
 #include <stdio.h>
 
 int main(int argc, char** argv)

Servers/SystemServer/main.cpp

@@ -26,7 +26,9 @@
 
 #include "Service.h"
 #include <AK/Assertions.h>
+#include <AK/ByteBuffer.h>
 #include <LibCore/ConfigFile.h>
+#include <LibCore/Event.h>
 #include <LibCore/EventLoop.h>
 #include <LibCore/File.h>
 #include <errno.h>

Userland/dmesg.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/ByteBuffer.h>
 #include <LibCore/File.h>
 #include <assert.h>
 #include <fcntl.h>

Userland/html.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/ByteBuffer.h>
 #include <LibCore/File.h>
 #include <LibGUI/AboutDialog.h>
 #include <LibGUI/Action.h>

Userland/man.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/ByteBuffer.h>
 #include <AK/String.h>
 #include <LibCore/File.h>
 #include <LibMarkdown/MDDocument.h>

Userland/md.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/ByteBuffer.h>
 #include <AK/String.h>
 #include <LibCore/File.h>
 #include <LibMarkdown/MDDocument.h>
@@ -45,7 +46,8 @@ int main(int argc, char* argv[])
         else
             file_name = argv[i];
 
-    auto file = Core::File::construct();;
+    auto file = Core::File::construct();
+    ;
     bool success;
     if (file_name == nullptr) {
         success = file->open(STDIN_FILENO, Core::IODevice::OpenMode::ReadOnly, Core::File::ShouldCloseFileDescription::No);

Userland/tail.cpp

@@ -25,6 +25,7 @@
  */
 
 #include <AK/Assertions.h>
+#include <AK/ByteBuffer.h>
 #include <LibCore/ArgsParser.h>
 #include <LibCore/File.h>
 #include <errno.h>