KeyboardSettings: Preselect the current keymap in the dropdown menu.

This is the little omission that I originally set out to fix, and
sure enough, I got to delve into Kernel land and back to implement
it. Lots of fun!

Applications/KeyboardSettings/main.cpp

@@ -26,8 +26,10 @@
 
 #include "CharacterMapFileListModel.h"
 #include <AK/QuickSort.h>
+#include <AK/JsonObject.h>
 #include <LibCore/ArgsParser.h>
 #include <LibCore/DirIterator.h>
+#include <LibCore/File.h>
 #include <LibGUI/AboutDialog.h>
 #include <LibGUI/Action.h>
 #include <LibGUI/Application.h>
@@ -67,13 +69,29 @@ int main(int argc, char** argv)
  return 1;
  }
 
+ if (unveil("/proc/keymap", "r") < 0) {
+ perror("unveil");
+ return 1;
+ }
+
  if (unveil(nullptr, nullptr)) {
  perror("unveil");
  return 1;
  }
 
  auto app_icon = GUI::Icon::default_icon("app-keyboard-settings");
 
+ auto proc_keymap = Core::File::construct("/proc/keymap");
+ if (!proc_keymap->open(Core::IODevice::OpenMode::ReadOnly))
+ ASSERT_NOT_REACHED();
+
+ auto json = JsonValue::from_string(proc_keymap->read_all());
+ ASSERT(json.has_value());
+ JsonObject keymap_object = json.value().as_object();
+ ASSERT(keymap_object.has("keymap"));
+ String current_keymap = keymap_object.get("keymap").to_string();
+ dbg() << "KeyboardSettings thinks the current keymap is: " << current_keymap;
+
  Vector<String> character_map_files;
  Core::DirIterator iterator("/res/keymaps/", Core::DirIterator::Flags::SkipDots);
  if (iterator.has_error()) {
@@ -88,6 +106,13 @@ int main(int argc, char** argv)
  }
  quick_sort(character_map_files);
 
+ size_t initial_keymap_index = SIZE_MAX;
+ for (size_t i = 0; i < character_map_files.size(); ++i) {
+ if (character_map_files[i].equals_ignoring_case(current_keymap))
+ initial_keymap_index = i;
+ }
+ ASSERT(initial_keymap_index < character_map_files.size());
+
  auto window = GUI::Window::construct();
  window->set_title("Keyboard settings");
  window->resize(300, 70);
@@ -115,6 +140,7 @@ int main(int argc, char** argv)
  character_map_file_combo.set_preferred_size(0, 22);
  character_map_file_combo.set_only_allow_values_from_model(true);
  character_map_file_combo.set_model(*CharacterMapFileListModel::create(character_map_files));
+ character_map_file_combo.set_selected_index(initial_keymap_index);
 
  root_widget.layout()->add_spacer();