Started to implement Issue #30. XDG folder structure. All weaknesses from the old system are still there:

HOME must be defined: Not a regression
Only one level of mkdir: Not a regression (but might be more relevant)

com_homepath is not fully implemented and it will need to be set to "openarena" instead of ".openarena". But that just makes it like Mac.

code/qcommon/q_shared.h

@@ -32,6 +32,7 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
   #define CLIENT_WINDOW_TITLE     	"OpenArena"
   #define CLIENT_WINDOW_MIN_TITLE 	"OA"
   #define HOMEPATH_NAME_UNIX		".openarena"
+  #define HOMEPATH_NAME_XDG         "openarena"
   #define HOMEPATH_NAME_WIN		"OpenArena"
   #define HOMEPATH_NAME_MACOSX		HOMEPATH_NAME_WIN
   #define GAMENAME_FOR_MASTER		"Quake3Arena"	// must NOT contain whitespace.  No servers show up if you use "openarena"

code/qcommon/qcommon.h

@@ -1110,7 +1110,7 @@ char    *Sys_DefaultAppPath(void);
 #endif
 
 void  Sys_SetDefaultHomePath(const char *path);
-char	*Sys_DefaultHomePath(void);
+const char *Sys_DefaultHomePath(void);
 const char *Sys_Dirname( char *path );
 const char *Sys_Basename( char *path );
 char *Sys_ConsoleInput(void);

code/sys/sys_unix.c

@@ -44,12 +44,138 @@ qboolean stdinIsATTY;
 // Used to determine where to store user-specific files
 static char homePath[ MAX_OSPATH ] = { 0 };
 
+/* Contains the XDG home path. Typically $HOME/.local/share/openarena */
+static char homeXdg[ MAX_OSPATH ] = { 0 };
+/* Contains the classic home path. Typically $HOME/.openarena */
+static char homeClassic[ MAX_OSPATH ] = { 0 };
+
+static const char* getHome(void) {
+	return getenv("HOME");
+}
+
+/**
+ * Concatenates the XDG pathname. Normally "openarena".
+ * @param dest Buffer to concatenate "openarea" to.
+ * @param n Size of buffer
+ */
+static void Sys_ConcatXdgHomepathName(char* dest, size_t n) {
+	if(com_homepath->string[0])
+		Q_strcat(dest, n, com_homepath->string);
+	else
+		Q_strcat(dest, n, HOMEPATH_NAME_XDG);
+}
+
+/**
+ * Assignes a buffer with the value of the Xdg home.
+ * Normally: "$HOME/.local/share/openarena"
+ * If it failes the destination buffer will be the empty string.
+ * @param dest Buffer to place the value into
+ * @param n Size of buffer
+ */
+static void Sys_SetXdgDataHomePath(char* dest, size_t n) {
+	const char* xdgDataPath = getenv("XDG_DATA_HOME");
+	dest[0] = '\0';
+	if (xdgDataPath) {
+		Com_sprintf(dest, n, "%s/", xdgDataPath);
+		Sys_ConcatXdgHomepathName(dest, n);
+		return;
+	}
+	const char* homeFolder = getHome();
+	if (homeFolder) {
+		Com_sprintf(dest, n, "%s/.local/share/", homeFolder);
+		Sys_ConcatXdgHomepathName(dest, n);
+	}
+}
+
+/**
+ * Sets the global variables homeClassic and home Xdg.
+ */
+static void Sys_SetHomePaths( void ) {
+	Sys_SetXdgDataHomePath(homeXdg, sizeof(homeXdg));
+	const char* p = getHome();
+	Com_sprintf(homeClassic, sizeof(homeClassic), "%s%c", p, PATH_SEP);
+	Q_strcat(homeClassic, sizeof(homeClassic), HOMEPATH_NAME_UNIX);
+}
+
+/**
+ * Retruns true if the file exists and is a symbolic link
+ * @param path The path to the file.
+ * @return True if it is a confirmed symbolic link, false otherwise.
+ */
+static qboolean Sys_IsSymbolic(const char* path) {
+	struct stat buf;
+    int errCode = lstat(path, &buf);
+	return (errCode == 0);
+}
+
+/**
+ * Checks if a given file exists and is a directory.
+ * @param path Path to the file
+ * @return True if it is a directory and false otherwise.
+ */
+static qboolean Sys_IsDir(const char* path) {
+	struct stat buf;
+	int errCode = stat(path, &buf);
+	if (errCode != 0) {
+		return qfalse;
+	}
+	return S_ISDIR(buf.st_mode);
+}
+
+/**
+ * Deletes a symbolic link if it does not point to a directory.
+ * Otherwise: Do nothing.
+ * @param path Path to the symlink.
+ */
+static void Sys_RemoveInvalidSymlinkToDir(const char* path) {
+	if (Sys_IsSymbolic(path) && !Sys_IsDir(path)) {
+		//If the file is symbolic but does not a dir then it must either be invalid or point to something not a dir.
+		unlink(path);
+	}
+}
+
+static void CreateXDGPathAndMisc( void ) {
+	Sys_SetHomePaths();
+	Sys_RemoveInvalidSymlinkToDir(homeXdg);
+	Sys_RemoveInvalidSymlinkToDir(homeClassic);
+	if (Sys_IsDir(homeXdg) && Sys_IsDir(homeClassic)) {
+		//Both classic and xdg homedirs both exists.
+		//In the future only test on homeXdg.
+		return;
+	}
+	if (Sys_IsDir(homeClassic) && !Sys_IsDir(homeXdg) ) {
+		//Try to move the old home dir to the new location.
+		int errCode = rename(homeClassic, homeXdg);
+		if (errCode) {
+			Com_Printf("Failed to move \"%s\" to \"%s\". Error code: %d. Non fatal.", homeClassic, homeXdg, errCode);
+		}
+	}
+	if (Sys_IsDir(homeXdg)) {
+		int errCode = Sys_Mkdir(homeXdg);
+		if (errCode) {
+			Com_Printf("Failed to create \"%s\". Error code: %d. This is quite bad.", homeXdg, errCode);
+		}
+	}
+	if (Sys_IsDir(homeXdg) && !Sys_IsDir(homeClassic)) {
+		int errCode = symlink(homeXdg, homeClassic);
+		if (errCode) {
+			Com_Printf("Failed to create symbolic link \"%s\". Error code: %d. This is quite bad.", homeClassic, errCode);
+		}
+	}
+	if (!Sys_IsDir(homeXdg) && Sys_IsDir(homeClassic)) {
+		int errCode = symlink(homeClassic, homeXdg);
+		if (errCode) {
+			Com_Printf("Failed to create symbolic link \"%s\". Error code: %d. This is quite bad.", homeXdg, errCode);
+		}
+	}
+}
+
 /*
 ==================
 Sys_DefaultHomePath
 ==================
 */
-char *Sys_DefaultHomePath(void)
+const char *Sys_DefaultHomePath(void)
 {
 	char *p;
 
@@ -67,10 +193,14 @@ char *Sys_DefaultHomePath(void)
 			else
 				Q_strcat(homePath, sizeof(homePath), HOMEPATH_NAME_MACOSX);
 #else
+#if 0
 			if(com_homepath->string[0])
 				Q_strcat(homePath, sizeof(homePath), com_homepath->string);
 			else
 				Q_strcat(homePath, sizeof(homePath), HOMEPATH_NAME_UNIX);
+#endif
+			CreateXDGPathAndMisc();
+			Com_sprintf(homePath, sizeof(homePath), "%s", homeXdg);
 #endif
 		}
 	}

code/sys/sys_win32.c

@@ -92,7 +92,7 @@ void Sys_SetFloatEnv(void)
 Sys_DefaultHomePath
 ================
 */
-char *Sys_DefaultHomePath( void )
+const char *Sys_DefaultHomePath( void )
 {
 	TCHAR szPath[MAX_PATH];
 	FARPROC qSHGetFolderPath;