LibGfx+WindowServer: Have WindowServer broadcast system font settings

Instead of everybody getting their system fonts from Gfx::FontDatabase
(where it's all hardcoded), they now get it from WindowServer.

These are then plumbed into the usual Gfx::FontDatabase places so that
the old default_font() and default_fixed_width_font() APIs keep working.

Userland/Libraries/LibGUI/WindowServerConnection.cpp

@@ -21,6 +21,7 @@
 #include <LibGUI/Window.h>
 #include <LibGUI/WindowServerConnection.h>
 #include <LibGfx/Bitmap.h>
+#include <LibGfx/FontDatabase.h>
 #include <LibGfx/Palette.h>
 #include <LibGfx/SystemTheme.h>
 
@@ -47,9 +48,11 @@ void WindowServerConnection::handshake()
     auto message = wait_for_specific_message<Messages::WindowClient::FastGreet>();
     set_system_theme_from_anonymous_buffer(message->theme_buffer());
     Desktop::the().did_receive_screen_rect({}, message->screen_rect());
+    Gfx::FontDatabase::set_default_font_query(message->default_font_query());
+    Gfx::FontDatabase::set_fixed_width_font_query(message->fixed_width_font_query());
 }
 
-void WindowServerConnection::fast_greet(Gfx::IntRect const&, Core::AnonymousBuffer const&)
+void WindowServerConnection::fast_greet(Gfx::IntRect const&, Core::AnonymousBuffer const&, String const&, String const&)
 {
     // NOTE: This message is handled in handshake().
 }
@@ -63,6 +66,12 @@ void WindowServerConnection::update_system_theme(Core::AnonymousBuffer const& th
     });
 }
 
+void WindowServerConnection::update_system_fonts(const String& default_font_query, const String& fixed_width_font_query)
+{
+    Gfx::FontDatabase::set_default_font_query(default_font_query);
+    Gfx::FontDatabase::set_fixed_width_font_query(fixed_width_font_query);
+}
+
 void WindowServerConnection::paint(i32 window_id, Gfx::IntSize const& window_size, Vector<Gfx::IntRect> const& rects)
 {
     if (auto* window = Window::from_window_id(window_id))

Userland/Libraries/LibGUI/WindowServerConnection.h

@@ -27,7 +27,7 @@ public:
     static WindowServerConnection& the();
 
 private:
-    virtual void fast_greet(Gfx::IntRect const&, Core::AnonymousBuffer const&) override;
+    virtual void fast_greet(Gfx::IntRect const&, Core::AnonymousBuffer const&, String const&, String const&) override;
     virtual void paint(i32, Gfx::IntSize const&, Vector<Gfx::IntRect> const&) override;
     virtual void mouse_move(i32, Gfx::IntPoint const&, u32, u32, u32, i32, bool, Vector<String> const&) override;
     virtual void mouse_down(i32, Gfx::IntPoint const&, u32, u32, u32, i32) override;
@@ -54,6 +54,7 @@ private:
     virtual void drag_accepted() override;
     virtual void drag_cancelled() override;
     virtual void update_system_theme(Core::AnonymousBuffer const&) override;
+    virtual void update_system_fonts(String const&, String const&) override;
     virtual void window_state_changed(i32, bool, bool) override;
     virtual void display_link_notification() override;
     virtual void ping() override;

Userland/Libraries/LibGfx/FontDatabase.cpp

@@ -24,24 +24,55 @@ FontDatabase& FontDatabase::the()
     return *s_the;
 }
 
+static RefPtr<Font> s_default_font;
+static String s_default_font_query;
+static RefPtr<Font> s_fixed_width_font;
+static String s_fixed_width_font_query;
+
+void FontDatabase::set_default_font_query(String query)
+{
+    if (s_default_font_query == query)
+        return;
+    s_default_font_query = move(query);
+    s_default_font = nullptr;
+}
+
+String FontDatabase::default_font_query()
+{
+    return s_default_font_query;
+}
+
 Font& FontDatabase::default_font()
 {
-    static Font* font;
-    if (!font) {
-        font = FontDatabase::the().get_by_name("Katica 10 400");
-        VERIFY(font);
+    if (!s_default_font) {
+        VERIFY(!s_default_font_query.is_empty());
+        s_default_font = FontDatabase::the().get_by_name(s_default_font_query);
+        VERIFY(s_default_font);
     }
-    return *font;
+    return *s_default_font;
+}
+
+void FontDatabase::set_fixed_width_font_query(String query)
+{
+    if (s_fixed_width_font_query == query)
+        return;
+    s_fixed_width_font_query = move(query);
+    s_fixed_width_font = nullptr;
+}
+
+String FontDatabase::fixed_width_font_query()
+{
+    return s_fixed_width_font_query;
 }
 
 Font& FontDatabase::default_fixed_width_font()
 {
-    static Font* font;
-    if (!font) {
-        font = FontDatabase::the().get_by_name("Csilla 10 400");
-        VERIFY(font);
+    if (!s_fixed_width_font) {
+        VERIFY(!s_fixed_width_font_query.is_empty());
+        s_fixed_width_font = FontDatabase::the().get_by_name(s_fixed_width_font_query);
+        VERIFY(s_fixed_width_font);
     }
-    return *font;
+    return *s_fixed_width_font;
 }
 
 struct FontDatabase::Private {

Userland/Libraries/LibGfx/FontDatabase.h

@@ -37,6 +37,11 @@ public:
     static Font& default_font();
     static Font& default_fixed_width_font();
 
+    static String default_font_query();
+    static String fixed_width_font_query();
+    static void set_default_font_query(String);
+    static void set_fixed_width_font_query(String);
+
     RefPtr<Gfx::Font> get(const String& family, unsigned size, unsigned weight);
     RefPtr<Gfx::Font> get(const String& family, const String& variant, unsigned size);
     RefPtr<Gfx::Font> get_by_name(const StringView&);

Userland/Libraries/LibWeb/OutOfProcessWebView.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2020-2021, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -15,6 +15,7 @@
 #include <LibGUI/Painter.h>
 #include <LibGUI/Scrollbar.h>
 #include <LibGUI/Window.h>
+#include <LibGfx/FontDatabase.h>
 #include <LibGfx/Palette.h>
 #include <LibGfx/SystemTheme.h>
 
@@ -69,6 +70,7 @@ void OutOfProcessWebView::create_client()
     };
 
     client().async_update_system_theme(Gfx::current_system_theme_buffer());
+    client().async_update_system_fonts(Gfx::FontDatabase::default_font_query(), Gfx::FontDatabase::fixed_width_font_query());
     client().async_update_screen_rect(GUI::Desktop::the().rect());
 }