LibCore: Add StandardPaths thing to retrieve various standard locations

Fixes #1853.

Applications/FileManager/main.cpp

@@ -33,7 +33,7 @@
 #include <LibCore/ConfigFile.h>
 #include <LibCore/DesktopServices.h>
 #include <LibCore/MimeData.h>
-#include <LibCore/UserInfo.h>
+#include <LibCore/StandardPaths.h>
 #include <LibGUI/AboutDialog.h>
 #include <LibGUI/Action.h>
 #include <LibGUI/ActionGroup.h>
@@ -91,7 +91,7 @@ int main(int argc, char** argv)
     }
 
     if (app.args().contains_slow("--desktop") || app.args().contains_slow("-d"))
-        return run_in_desktop_mode(move(config), String::format("%s/Desktop", get_current_user_home_path().characters()));
+        return run_in_desktop_mode(move(config), Core::StandardPaths::desktop_directory());
 
     // our initial location is defined as, in order of precedence:
     // 1. the first command-line argument (e.g. FileManager /bin)
@@ -103,7 +103,7 @@ int main(int argc, char** argv)
         initial_location = argv[1];
 
     if (initial_location.is_empty())
-        initial_location = get_current_user_home_path();
+        initial_location = Core::StandardPaths::home_directory();
 
     if (initial_location.is_empty())
         initial_location = "/";
@@ -530,7 +530,7 @@ int run_in_windowed_mode(RefPtr<Core::ConfigFile> config, String initial_locatio
 
     auto go_home_action = GUI::CommonActions::make_go_home_action(
         [&](auto&) {
-            directory_view.open(get_current_user_home_path());
+            directory_view.open(Core::StandardPaths::home_directory());
         },
         window);
 

Applications/SystemMenu/main.cpp

@@ -28,7 +28,7 @@
 #include <AK/QuickSort.h>
 #include <LibCore/ConfigFile.h>
 #include <LibCore/DirIterator.h>
-#include <LibCore/UserInfo.h>
+#include <LibCore/StandardPaths.h>
 #include <LibGUI/Action.h>
 #include <LibGUI/Application.h>
 #include <LibGUI/Desktop.h>
@@ -81,7 +81,7 @@ int main(int argc, char** argv)
         return 1;
     }
 
-    if (chdir(get_current_user_home_path().characters()) < 0) {
+    if (chdir(Core::StandardPaths::home_directory().characters()) < 0) {
         perror("chdir");
         return 1;
     }

Applications/Taskbar/TaskbarWindow.cpp

@@ -28,7 +28,7 @@
 #include "TaskbarButton.h"
 #include <AK/SharedBuffer.h>
 #include <LibCore/ConfigFile.h>
-#include <LibCore/UserInfo.h>
+#include <LibCore/StandardPaths.h>
 #include <LibGUI/BoxLayout.h>
 #include <LibGUI/Button.h>
 #include <LibGUI/Desktop.h>
@@ -105,7 +105,7 @@ void TaskbarWindow::create_quick_launch_bar()
             if (pid < 0) {
                 perror("fork");
             } else if (pid == 0) {
-                if (chdir(get_current_user_home_path().characters()) < 0) {
+                if (chdir(Core::StandardPaths::home_directory().characters()) < 0) {
                     perror("chdir");
                     exit(1);
                 }

Applications/Terminal/main.cpp

@@ -26,7 +26,6 @@
 
 #include <Kernel/KeyCode.h>
 #include <LibCore/ArgsParser.h>
-#include <LibCore/UserInfo.h>
 #include <LibGUI/AboutDialog.h>
 #include <LibGUI/Action.h>
 #include <LibGUI/ActionGroup.h>

Libraries/LibCore/ConfigFile.cpp

@@ -27,7 +27,7 @@
 #include <AK/StringBuilder.h>
 #include <LibCore/ConfigFile.h>
 #include <LibCore/File.h>
-#include <LibCore/UserInfo.h>
+#include <LibCore/StandardPaths.h>
 #include <pwd.h>
 #include <stdio.h>
 #include <unistd.h>
@@ -36,9 +36,7 @@ namespace Core {
 
 NonnullRefPtr<ConfigFile> ConfigFile::get_for_app(const String& app_name)
 {
-    String home_path = get_current_user_home_path();
+    String home_path = StandardPaths::home_directory();
-    if (home_path == "/")
-        home_path = String::format("/tmp");
     auto path = String::format("%s/%s.ini", home_path.characters(), app_name.characters());
     return adopt(*new ConfigFile(path));
 }

Libraries/LibCore/Makefile

@@ -23,12 +23,12 @@ OBJS = \
     ProcessStatisticsReader.o \
     Socket.o \
     SocketAddress.o \
+    StandardPaths.o \
     TCPServer.o \
     TCPSocket.o \
     Timer.o \
     UDPServer.o \
     UDPSocket.o \
-    UserInfo.o \
     puff.o
 
 LIBRARY = libcore.a

Libraries/LibCore/StandardPaths.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -24,18 +24,38 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <LibCore/UserInfo.h>
+#include <AK/FileSystemPath.h>
+#include <AK/String.h>
+#include <AK/StringBuilder.h>
+#include <LibCore/StandardPaths.h>
 #include <pwd.h>
 #include <stdlib.h>
 #include <unistd.h>
 
-String get_current_user_home_path()
+namespace Core {
+
+String StandardPaths::home_directory()
 {
     if (auto* home_env = getenv("HOME"))
-        return home_env;
+        return canonicalized_path(home_env);
 
     auto* pwd = getpwuid(getuid());
     String path = pwd ? pwd->pw_dir : "/";
     endpwent();
-    return path;
+    return canonicalized_path(path);
+}
+
+String StandardPaths::desktop_directory()
+{
+    StringBuilder builder;
+    builder.append(home_directory());
+    builder.append("/Desktop");
+    return canonicalized_path(builder.to_string());
+}
+
+String StandardPaths::tempfile_directory()
+{
+    return "/tmp";
+}
+
 }

Libraries/LibCore/StandardPaths.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -26,6 +26,15 @@
 
 #pragma once
 
-#include <AK/String.h>
+#include <AK/Forward.h>
 
-String get_current_user_home_path();
+namespace Core {
+
+class StandardPaths {
+public:
+    static String home_directory();
+    static String desktop_directory();
+    static String tempfile_directory();
+};
+
+}

Libraries/LibGUI/FilePicker.cpp

@@ -128,7 +128,7 @@ FilePicker::FilePicker(Mode mode, const StringView& file_name, const StringView&
     toolbar.add_action(*open_parent_directory_action);
 
     auto go_home_action = CommonActions::make_go_home_action([this](auto&) {
-        m_model->set_root_path(get_current_user_home_path());
+        m_model->set_root_path(Core::StandardPaths::home_directory());
     });
     toolbar.add_action(go_home_action);
     toolbar.add_separator();

Libraries/LibGUI/FilePicker.h

@@ -26,7 +26,7 @@
 
 #include <AK/FileSystemPath.h>
 #include <AK/Optional.h>
-#include <LibCore/UserInfo.h>
+#include <LibCore/StandardPaths.h>
 #include <LibGUI/Dialog.h>
 
 namespace GUI {
@@ -52,7 +52,7 @@ private:
     void clear_preview();
     void on_file_return();
 
-    FilePicker(Mode type = Mode::Open, const StringView& file_name = "Untitled", const StringView& path = String(get_current_user_home_path()), Window* parent_window = nullptr);
+    FilePicker(Mode type = Mode::Open, const StringView& file_name = "Untitled", const StringView& path = Core::StandardPaths::home_directory(), Window* parent_window = nullptr);
 
     static String ok_button_name(Mode mode)
     {