Add initial support for the XDG Base Directory spec

Spec version 0.7 from https://standards.freedesktop.org/basedir-spec/basedir-spec-0.7.html
(latest as of this commit).

Three virtual methods are added to OS for the various XDG paths we will use:
- OS::get_data_path gives XDG_DATA_HOME, or if missing:
  ~/.local/share on X11, ~/Library/Application Support/ on macOS and %APPDATA% on Windows
- OS::get_config_path gives XDG_CONFIG_HOME, or if missing:
  ~/.config on X11, ~/Library/Application Support/ on macOS and %APPDATA% on Windows
- OS::get_cache_path gives XDG_CACHE_HOME, or if missing:
  ~/.cache on X11, ~/Library/Caches on macOS and %APPDATA% on Windows

So for Windows there are no changes, for Linux we follow the full split spec
and for macOS stuff will move from ~/.godot to ~/Library/Application Support/Godot.

Support for system-wide installation of templates on Unix was removed for now,
as it's a bit hackish and I don't think anyone uses it.

user:// will still be OS::get_data_path() + "/godot/app_userdata/$name" by
default, but when using the application/config/use_shared_user_dir option
it will now use XDG_DATA_HOME/$name, e.g. ~/.local/share/MyGame.

For now everything still goes in EditorSettings::get_settings_dir(), but
this will be changed in a later commit to make use of the new splitting
where relevant.

Part of #3513.

2 files changed, 43 insertions, 0 deletions

diff --git a/platform/osx/os_osx.h b/platform/osx/os_osx.h
index 1df847eb79..aa8ee1fe83 100644
--- a/platform/osx/os_osx.h
+++ b/platform/osx/os_osx.h
@@ -154,6 +154,11 @@ public:
 
 	virtual MainLoop *get_main_loop() const;
 
+	virtual String get_config_path() const;
+	virtual String get_data_path() const;
+	virtual String get_cache_path() const;
+	virtual String get_godot_dir_name() const;
+
 	virtual String get_system_dir(SystemDir p_dir) const;
 
 	virtual bool can_draw() const;
diff --git a/platform/osx/os_osx.mm b/platform/osx/os_osx.mm
index 49d94da9e1..391c697ae9 100644
--- a/platform/osx/os_osx.mm
+++ b/platform/osx/os_osx.mm
@@ -36,6 +36,7 @@
 #include "print_string.h"
 #include "sem_osx.h"
 #include "servers/visual/visual_server_raster.h"
+#include "version_generated.gen.h"
 
 #include <Carbon/Carbon.h>
 #import <Cocoa/Cocoa.h>
@@ -1340,6 +1341,43 @@ MainLoop *OS_OSX::get_main_loop() const {
 	return main_loop;
 }
 
+String OS_OSX::get_config_path() const {
+
+	if (has_environment("XDG_CONFIG_HOME")) {
+		return get_environment("XDG_CONFIG_HOME");
+	} else if (has_environment("HOME")) {
+		return get_environment("HOME").plus_file("Library/Application Support");
+	} else {
+		return ".";
+	}
+}
+
+String OS_OSX::get_data_path() const {
+
+	if (has_environment("XDG_DATA_HOME")) {
+		return get_environment("XDG_DATA_HOME");
+	} else {
+		return get_config_path();
+	}
+}
+
+String OS_OSX::get_cache_path() const {
+
+	if (has_environment("XDG_CACHE_HOME")) {
+		return get_environment("XDG_CACHE_HOME");
+	} else if (has_environment("HOME")) {
+		return get_environment("HOME").plus_file("Library/Caches");
+	} else {
+		return get_config_path();
+	}
+}
+
+// Get properly capitalized engine name for system paths
+String OS_OSX::get_godot_dir_name() const {
+
+	return String(_MKSTR(VERSION_SHORT_NAME)).capitalize();
+}
+
 String OS_OSX::get_system_dir(SystemDir p_dir) const {
 
 	NSSearchPathDirectory id = 0;