[pull] master from MusicPlayerDaemon:master

NEWS

@@ -12,6 +12,8 @@ ver 0.25 (not yet released)
 * player
   - support replay gain parameter in stream URI
   - preallocate physical RAM for audio buffer when playback starts
+* configuration
+  - support $XDG_DATA_HOME, $XDG_STATE_HOME
 * switch to C++23
 * require Meson 1.2
 

doc/mpd.conf.5.rst

@@ -33,7 +33,9 @@ supported:
 - ``$XDG_CONFIG_HOME``
 - ``$XDG_MUSIC_DIR``
 - ``$XDG_CACHE_HOME``
+- ``$XDG_DATA_HOME``
 - ``$XDG_RUNTIME_DIR``
+- ``$XDG_STATE_HOME``
 
 Example:
 

doc/mpdconf.example

@@ -55,7 +55,7 @@
 # it was brought down. This setting is disabled by default and the server
 # state will be reset on server start up.
 #
-#state_file			"$XDG_RUNTIME_DIR/mpd/state"
+#state_file			"$XDG_STATE_HOME/mpd/state"
 #state_file			"~/.mpd/state"
 #
 # The location of the sticker database.  This is a database which

src/config/Path.cxx

@@ -81,10 +81,14 @@ GetVariable(std::string_view name)
 		return GetUserConfigDir();
 	else if (name == "XDG_MUSIC_DIR"sv)
 		return GetUserMusicDir();
+	else if (name == "XDG_DATA_HOME"sv)
+		return GetUserDataDir();
 	else if (name == "XDG_CACHE_HOME"sv)
 		return GetUserCacheDir();
 	else if (name == "XDG_RUNTIME_DIR"sv)
 		return GetUserRuntimeDir();
+	else if (name == "XDG_STATE_HOME"sv)
+		return GetUserStateDir();
 	else
 		throw FmtRuntimeError("Unknown variable: {:?}", name);
 }

src/fs/glue/StandardDirectory.cxx

@@ -345,6 +345,39 @@ GetAppCacheDir() noexcept
 #endif
 }
 
+AllocatedPath
+GetUserDataDir() noexcept
+{
+#ifdef USE_XDG
+	// Check for $XDG_DATA_HOME
+	if (const auto path = GetExistingEnvDirectory("XDG_DATA_HOME");
+	    path != nullptr)
+		return AllocatedPath{path};
+
+	// Check for $HOME/.local/share
+	if (const auto home = GetHomeDir(); !home.IsNull())
+		if (auto fallback = home / Path::FromFS(".local/share");
+		    IsValidDir(fallback))
+			return fallback;
+
+#endif
+	return nullptr;
+}
+
+AllocatedPath
+GetAppDataDir() noexcept
+{
+#if defined(USE_XDG)
+	if (const auto user_dir = GetUserDataDir(); !user_dir.IsNull()) {
+		auto dir = user_dir / app_filename;
+		CreateDirectoryNoThrow(dir);
+		return dir;
+	}
+
+#endif
+	return nullptr;
+}
+
 AllocatedPath
 GetUserRuntimeDir() noexcept
 {
@@ -386,6 +419,47 @@ GetAppRuntimeDir() noexcept
 	return nullptr;
 }
 
+AllocatedPath
+GetUserStateDir() noexcept
+{
+#ifdef USE_XDG
+	// Check for $XDG_STATE_HOME
+	if (const auto path = GetExistingEnvDirectory("XDG_STATE_HOME");
+	    path != nullptr)
+		return AllocatedPath{path};
+
+	// Check for $HOME/.local/state
+	if (const auto home = GetHomeDir(); !home.IsNull())
+		if (auto fallback = home / Path::FromFS(".local/state");
+		    IsValidDir(fallback))
+			return fallback;
+#endif
+
+	return nullptr;
+}
+
+AllocatedPath
+GetAppStateDir() noexcept
+{
+#if defined(__linux__) && !defined(ANDROID)
+	/* systemd specific; see systemd.exec(5) */
+	if (const char *state_directory = getenv("STATE_DIRECTORY"))
+		if (auto dir = Split(std::string_view{state_directory}, ':').first;
+		    !dir.empty())
+			return AllocatedPath::FromFS(dir);
+#endif
+
+#if defined(USE_XDG)
+	if (const auto user_dir = GetUserStateDir(); !user_dir.IsNull()) {
+		auto dir = user_dir / app_filename;
+		CreateDirectoryNoThrow(dir);
+		return dir;
+	}
+#endif
+
+	return nullptr;
+}
+
 #ifdef _WIN32
 
 AllocatedPath

src/fs/glue/StandardDirectory.hxx

@@ -26,6 +26,20 @@ GetUserMusicDir() noexcept;
 AllocatedPath
 GetUserCacheDir() noexcept;
 
+/**
+ * Obtains data directory for this application.
+ */
+[[gnu::const]]
+AllocatedPath
+GetAppDataDir() noexcept;
+
+/**
+ * Obtains data directory for the current user.
+ */
+[[gnu::const]]
+AllocatedPath
+GetUserDataDir() noexcept;
+
 /**
  * Obtains cache directory for this application.
  */
@@ -47,6 +61,20 @@ GetUserRuntimeDir() noexcept;
 AllocatedPath
 GetAppRuntimeDir() noexcept;
 
+/**
+ * Obtains the state directory for the current user.
+ */
+[[gnu::const]]
+AllocatedPath
+GetUserStateDir() noexcept;
+
+/**
+ * Obtains the state directory for this application.
+ */
+[[gnu::const]]
+AllocatedPath
+GetAppStateDir() noexcept;
+
 #ifdef _WIN32
 
 /**

test/fs/TestParsePath.cxx

@@ -68,6 +68,26 @@ GetAppCacheDir() noexcept
 #endif
 }
 
+AllocatedPath
+GetUserDataDir() noexcept
+{
+#ifdef _WIN32
+	return nullptr;
+#else
+	return AllocatedPath::FromFS(PATH_LITERAL("/home/foo/.local/share"));
+#endif
+}
+
+AllocatedPath
+GetAppDataDir() noexcept
+{
+#ifdef _WIN32
+	return nullptr;
+#else
+	return GetUserDataDir() / AllocatedPath::FromFS(PATH_LITERAL("mpd"));
+#endif
+}
+
 AllocatedPath
 GetUserRuntimeDir() noexcept
 {
@@ -88,6 +108,26 @@ GetAppRuntimeDir() noexcept
 #endif
 }
 
+AllocatedPath
+GetUserStateDir() noexcept
+{
+#ifdef _WIN32
+	return nullptr;
+#else
+	return AllocatedPath::FromFS(PATH_LITERAL("/home/foo/.local/state"));
+#endif
+}
+
+AllocatedPath
+GetAppStateDir() noexcept
+{
+#ifdef _WIN32
+	return nullptr;
+#else
+	return GetUserStateDir() / AllocatedPath::FromFS(PATH_LITERAL("mpd"));
+#endif
+}
+
 const char *
 ConfigData::GetString([[maybe_unused]] ConfigOption option,
 		      const char *default_value) const noexcept
@@ -136,7 +176,11 @@ TEST(ParsePath, XDG)
 	EXPECT_EQ(ParsePath("$XDG_CONFIG_HOME/abc"), AllocatedPath::FromFS(PATH_LITERAL("/home/foo/.config/abc")));
 	EXPECT_EQ(ParsePath("$XDG_MUSIC_DIR"), AllocatedPath::FromFS(PATH_LITERAL("/home/foo/Music")));
 	EXPECT_EQ(ParsePath("$XDG_CACHE_HOME"), AllocatedPath::FromFS(PATH_LITERAL("/home/foo/.cache")));
+	EXPECT_EQ(ParsePath("$XDG_DATA_HOME"), AllocatedPath::FromFS(PATH_LITERAL("/home/foo/.local/share")));
+	EXPECT_EQ(ParsePath("$XDG_DATA_HOME/mpd"), AllocatedPath::FromFS(PATH_LITERAL("/home/foo/.local/share/mpd")));
 	EXPECT_EQ(ParsePath("$XDG_RUNTIME_DIR/mpd"), AllocatedPath::FromFS(PATH_LITERAL("/run/user/foo/mpd")));
+	EXPECT_EQ(ParsePath("$XDG_STATE_HOME"), AllocatedPath::FromFS(PATH_LITERAL("/home/foo/.local/state")));
+	EXPECT_EQ(ParsePath("$XDG_STATE_HOME/mpd"), AllocatedPath::FromFS(PATH_LITERAL("/home/foo/.local/state/mpd")));
 }
 
 #endif