Use $XDG_CONFIG_HOME for config files if poosible

Fallback to com_gamedir. Also detriplicate code for finding the path of
the config file.
Change Signature for Sys_HomeDirectory since it's no longer const.

cl_main.c

@@ -2915,7 +2915,7 @@ static void AuthUsernameChanged(cvar_t* var, char* value, qbool* cancel)
 	strlcpy(filename, value, sizeof(filename));
 	COM_ForceExtensionEx(filename, ".apikey", sizeof(filename));
 
-	Cfg_GetConfigPath(path, sizeof(path), filename);
+	Cfg_GetConfigPath(path, sizeof(path), filename, cfg_use_home.integer);
 
 	auth_token = FS_LoadTempFile(path, &auth_token_length);
 	if (auth_token == 0) {

config_manager.c

@@ -798,6 +798,15 @@ static void ResetConfigs(qbool explicit_reset, qbool read_legacy_configs)
 
 void Cfg_GetConfigPath(char* path, size_t max_length, const char* name)
 {
+	char *configdir;
+#ifdef _WIN32
+	configdir = com_homedir;
+#else
+	configdir = getenv("XDG_CONFIG_HOME");
+	if (!configdir)
+		configdir = com_homedir;
+#endif
+
 	const char* default_gamedir = (cfg_use_home.integer ? "" : "ezquake");
 	const char* base_directory = (cfg_use_home.integer ? com_homedir : com_basedir);
 
@@ -1032,8 +1041,8 @@ qbool LoadCfg(FILE *f)
 	example how it works
 	
 	=== ./ezquake -game testmod -config testcfg
-	homedir/testmod/testcfg.cfg (fullname)
-	homedir/testcfg.cfg (fullname_moddefault)
+	homedir/testmod/testcfg.cfg
+	homedir/testcfg.cfg
 	quakedir/testmod/configs/testcfg.cfg
 	quakedir/ezquake/configs/testcfg.cfg
 	built-in ezquake config
@@ -1043,59 +1052,45 @@ void LoadConfig_f(void)
 	FILE	*f = NULL;
 	char	filename[MAX_PATH] = {0},
 			fullname[MAX_PATH] = {0},
-			fullname_moddefault[MAX_PATH] = {0},
 			*arg1;
-	int		use_home;
+	int		use_home, use_gamedir;
 
 	arg1 = COM_SkipPathWritable(Cmd_Argv(1));
 
 	snprintf(filename, sizeof(filename) - 4, "%s", arg1[0] ? arg1 : MAIN_CONFIG_FILENAME); // use config.cfg if no params was specified
+
 
 	COM_ForceExtensionEx (filename, ".cfg", sizeof (filename));
-	use_home = cfg_use_home.integer || !host_everything_loaded;
-
-	// home
-	snprintf(fullname, sizeof(fullname), "%s/%s%s", com_homedir, (strcmp(com_gamedirfile, "qw") == 0) ? "" : va("%s/", com_gamedirfile), filename);
-	snprintf(fullname_moddefault, sizeof(fullname_moddefault), "%s/%s", com_homedir, filename);
 
-	if (use_home) {
-		if (cfg_use_gamedir.integer) {
-			f = fopen(fullname, "rb");
-		}
-		if (f == NULL) {
-			f = fopen(fullname_moddefault, "rb");
-		}
-		if (f == NULL) {
-			use_home = false;
-		}
-	}
-
-	// basedir
-	snprintf(fullname, sizeof(fullname), "%s/%s/configs/%s", com_basedir, (strcmp(com_gamedirfile, "qw") == 0) ? "ezquake" : com_gamedirfile, filename);
-	snprintf(fullname_moddefault, sizeof(fullname_moddefault), "%s/ezquake/configs/%s", com_basedir, filename);
+	//save state of config vars
+	use_home = cfg_use_home.integer || !host_everything_loaded;
+	use_gamedir = cfg_use_gamedir.integer;
 
-	if(!use_home) {
-		if (cfg_use_gamedir.integer) {
-			f = fopen(fullname, "rb");
-		}
-		if (f == NULL) {
-			f = fopen(fullname_moddefault, "rb");
-		}
-	}
+	cf_use_home.integer = use_home || !host_everything_loaded;
 
-	if (f == NULL) {
-		Com_Printf("Couldn't load %s %s\n", filename, (cfg_use_gamedir.integer) ? "(using gamedir search)" : "(not using gamedir search)");
-		return;
+	while (!(f = fopen(Cfg_GetConfigPath(fullname, sizeof (fullname), filename), "rb"))) {
+		if (!(use_home || use_gamedir))
+			Com_Printf("Couldn't load %s %s\n", filename, (cfg_use_gamedir.integer) ? "(using gamedir search)" : "(not using gamedir search)");
+			cfg_use_gamedir.integer = use_gamedir;
+			cfg_use_home.integer = use_homedir;
+			return;
+		if (cfg_use_gamedir.integer)
+			cfg_use_gamedir.integer = 0;
+		continue;
+		cfg_use_home.integer = false;
+		cfg_use_gamedir.integer = use_gamedir;
 	}
 
 	con_suppress = true;
 	ResetConfigs(false, true);
 	con_suppress = false;
 
 	if(use_home)
-		Com_Printf("Loading %s%s (Using Home Directory) ...\n", (strcmp(com_gamedirfile, "qw") == 0) ? "" : va("%s/",com_gamedirfile), filename);
+		Com_Printf("Loading %s (Using Home Directory) ...\n", fullename);
 	else
-		Com_Printf("Loading %s/configs/%s ...\n", (strcmp(com_gamedirfile, "qw") == 0) ? "ezquake" : com_gamedirfile, filename);
+		Com_Printf("Loading %s ...\n", fullename);
+
+	cfg_use_home.integer = use_homedir;
 
 	Cbuf_AddText ("cl_warncmd 0\n");
 

fs.c

@@ -572,7 +572,7 @@ void FS_AddUserDirectory(char *dir)
 	case 3: snprintf(com_userdir, sizeof(com_userdir), "%s/qw/%s", com_basedir, userdirfile); break;
 	case 4: snprintf(com_userdir, sizeof(com_userdir), "%s/%s", com_basedir, userdirfile); break;
 	case 5: {
-		const char* homedir;
+		char* homedir;
 #ifdef _WIN32
 		homedir = Sys_HomeDirectory();
 #else

menu_options.c

@@ -615,12 +615,9 @@ extern cvar_t cfg_backup, cfg_save_aliases, cfg_save_binds, cfg_save_cmdline,
 
 void MOpt_ImportConfig(void) {
 	MOpt_configpage_mode = MOCPM_CHOOSECONFIG;
+	char path[MAX_OSPATH];
 
-	// hope few doubled trinary operator won't hurt your brains
-	if (cfg_use_home.integer)
-		FL_SetCurrentDir(&configs_filelist, (cfg_use_gamedir.integer) ? va("%s/%s", com_homedir, (strcmp(com_gamedirfile, "qw") == 0) ? "" : com_gamedirfile) : com_homedir);
-    else
-		FL_SetCurrentDir(&configs_filelist, (cfg_use_gamedir.integer) ? va("%s/%s/configs", com_basedir, (strcmp(com_gamedirfile, "qw") == 0) ? "ezquake" : com_gamedirfile) : va("%s/ezquake/configs", com_basedir));
+	FL_SetCurrentDir(&configs_filelist, Cfg_GetConfigPath(path, sizeof (path), ""))
 }
 void MOpt_ExportConfig(void) {
 	MOpt_configpage_mode = MOCPM_ENTERFILENAME;

sys.h

@@ -217,4 +217,5 @@ void *Sys_GetAddressForName(dllhandle_t *module, const char *exportname);
 void Sys_CvarInit(void);
 
 const char* Sys_FontsDirectory(void);
-const char* Sys_HomeDirectory(void);
+// Directoy for User's data files. returns string allocated with malloc. Must be freed.
+char* Sys_HomeDirectory(void);

sys_posix.c

@@ -735,7 +735,7 @@ const char* Sys_FontsDirectory(void)
 	return sys_fontsdir.string;
 }
 
-const char* Sys_HomeDirectory(void)
+char* Sys_HomeDirectory(void)
 {
     char *ev, *buf;
     if (!(ev = getenv("XDG_DATA_HOME"))) {
@@ -767,7 +767,7 @@ void Sys_RegisterQWURLProtocol_f(void)
     char open_cmd[MAX_PATH*2+1024] = { 0 };
     char exe_path[MAX_PATH] = { 0 };
     char buf[MAX_PATH] = { 0 };
-    const char *homedir = Sys_HomeDirectory();
+    char *homedir = Sys_HomeDirectory();
     int nchar = -1;
     FILE *fptr;
 

sys_win.c

@@ -1654,7 +1654,7 @@ const char* Sys_FontsDirectory(void)
 	return path;
 }
 
-const char* Sys_HomeDirectory(void)
+char* Sys_HomeDirectory(void)
 {
 	char path[MAX_OSPATH], *res;