Re-add old Xinerama code for the poor nvidia users

Add --force-xinerama when starting i3 to use Xinerama instead of RandR.
This should *ONLY* be done if you have no other choice (nvidia’s
binary driver uses twinview and does not expose the monitor information
through RandR).

include/i3.h

@@ -32,7 +32,6 @@ extern TAILQ_HEAD(autostarts_head, Autostart) autostarts;
 extern TAILQ_HEAD(assignments_head, Assignment) assignments;
 extern SLIST_HEAD(stack_wins_head, Stack_Window) stack_wins;
 extern xcb_event_handlers_t evenths;
-extern int num_screens;
 extern uint8_t root_depth;
 extern bool xkb_supported;
 extern xcb_atom_t atoms[NUM_ATOMS];

include/randr.h

@@ -24,6 +24,19 @@ extern struct outputs_head outputs;
  */
 void initialize_randr(xcb_connection_t *conn, int *event_base);
 
+/**
+ * Disables RandR support by creating exactly one output with the size of the
+ * X11 screen.
+ *
+ */
+void disable_randr(xcb_connection_t *conn);
+
+/**
+ * Initializes the specified output, assigning the specified workspace to it.
+ *
+ */
+void initialize_output(xcb_connection_t *conn, Output *output, Workspace *workspace);
+
 /**
  * (Re-)queries the outputs via RandR and stores them in the list of outputs.
  *

include/xinerama.h

@@ -0,0 +1,23 @@
+/*
+ * vim:ts=8:expandtab
+ *
+ * i3 - an improved dynamic tiling window manager
+ *
+ * © 2009-2010 Michael Stapelberg and contributors
+ *
+ * See file LICENSE for license information.
+ *
+ */
+#include "data.h"
+
+#ifndef _XINERAMA_H
+#define _XINERAMA_H
+
+/**
+ * We have just established a connection to the X server and need the initial
+ * Xinerama information to setup workspaces for each screen.
+ *
+ */
+void initialize_xinerama(xcb_connection_t *conn);
+
+#endif