support for user directories, based on a patch by Piotr Szymaniak.
against quakespasm svn revision 97.
** !! in alpha state, minimally tested, and certainly outdated !! **

Index: Quake/common.c
===================================================================
--- Quake/common.c	(revision 301)
+++ Quake/common.c	(working copy)
@@ -1778,25 +1778,27 @@
 COM_AddGameDirectory -- johnfitz -- modified based on topaz's tutorial
 =================
 */
-void COM_AddGameDirectory (const char *dir)
+void COM_AddGameDirectory (const char *base, const char *dir)
 {
 	int i;
 	searchpath_t *search;
 	pack_t *pak;
 	char pakfile[MAX_OSPATH];
 
-	strcpy (com_gamedir, dir);
+	if (!base)
+		return;
+	strcpy(com_gamedir, va("%s/%s", base, dir));
 
 	// add the directory to the search path
 	search = (searchpath_t *) Z_Malloc(sizeof(searchpath_t));
-	strcpy (search->filename, dir);
+	strcpy (search->filename, com_gamedir);
 	search->next = com_searchpaths;
 	com_searchpaths = search;
 
 	// add any pak files in the format pak0.pak pak1.pak, ...
 	for (i = 0; ; i++)
 	{
-		sprintf (pakfile, "%s/pak%i.pak", dir, i);
+		sprintf (pakfile, "%s/pak%i.pak", com_gamedir, i);
 		pak = COM_LoadPackFile (pakfile);
 		if (!pak)
 			break;
@@ -1839,7 +1841,12 @@
 {
 	int i, j;
 	searchpath_t *search;
+	char *home;
 
+	home = getenv("HOME");
+	if (home)
+		Sys_mkdir (va("%s/.quakespasm", home));
+
 	i = COM_CheckParm ("-basedir");
 	if (i && i < com_argc-1)
 		strcpy (com_basedir, com_argv[i + 1]);
@@ -1854,8 +1861,8 @@
 	}
 
 	// start up with GAMENAME by default (id1)
-	COM_AddGameDirectory (va("%s/"GAMENAME, com_basedir));
-	strcpy (com_gamedir, va("%s/"GAMENAME, com_basedir));
+	COM_AddGameDirectory(com_basedir, GAMENAME);
+	COM_AddGameDirectory(home, ".quakespasm/" GAMENAME);
 
 	if (!fitzmode)
 	{ /* QuakeSpasm customization: */
@@ -1867,17 +1874,20 @@
 	com_nummissionpacks = 0;
 	if (COM_CheckParm ("-rogue"))
 	{
-		COM_AddGameDirectory (va("%s/rogue", com_basedir));
+		COM_AddGameDirectory(com_basedir, "rogue");
+		COM_AddGameDirectory(home, ".quakespasm/rogue");
 		com_nummissionpacks++;
 	}
 	if (COM_CheckParm ("-hipnotic"))
 	{
-		COM_AddGameDirectory (va("%s/hipnotic", com_basedir));
+		COM_AddGameDirectory(com_basedir, "hipnotic");
+		COM_AddGameDirectory(home, ".quakespasm/hipnotic");
 		com_nummissionpacks++;
 	}
 	if (COM_CheckParm ("-quoth"))
 	{
-		COM_AddGameDirectory (va("%s/quoth", com_basedir));
+		COM_AddGameDirectory(com_basedir, "quoth");
+		COM_AddGameDirectory(home, ".quakespasm/quoth");
 		com_nummissionpacks++;
 	}
 	//johnfitz
@@ -1886,9 +1896,14 @@
 	if (i && i < com_argc-1)
 	{
 		com_modified = true;
-		COM_AddGameDirectory (va("%s/%s", com_basedir, com_argv[i + 1]));
+		COM_AddGameDirectory(com_basedir, com_argv[i + 1]);
+		COM_AddGameDirectory(home, va(".quakespasm/%s", com_argv[i + 1]));
 	}
 
+	/* If home is available, create the game directory */
+	if (home)
+		Sys_mkdir(com_gamedir);
+
 	i = COM_CheckParm ("-path");
 	if (i)
 	{