compositor-x11: Add base XCB/XKB support

Try to find the XKB extension, to be used in later commits.

Signed-off-by: Daniel Stone <daniel@fooishbar.org>

configure.ac

@@ -65,8 +65,26 @@ if test x$enable_x11_compositor = xyes; then
   LIBS=$xcb_save_LIBS
   CFLAGS=$xcb_save_CFLAGS
 
+  X11_COMPOSITOR_MODULES="x11 x11-xcb"
+
+  PKG_CHECK_MODULES(X11_COMPOSITOR_XKB, [xcb-xkb],
+		    [have_xcb_xkb="yes"], [have_xcb_xkb="no"])
+  if test "x$have_xcb_xkb" = xyes; then
+	# Most versions of XCB have totally broken XKB bindings, where the
+	# events don't work.  Make sure we can actually use them.
+	xcb_xkb_save_CFLAGS=$CFLAGS
+	CFLAGS=$X11_COMPOSITOR_XKB_CFLAGS
+	AC_CHECK_MEMBER([struct xcb_xkb_state_notify_event_t.xkbType],
+			[], [have_xcb_xkb=no], [[#include <xcb/xkb.h>]])
+	CFLAGS=$xcb_xkb_save_CFLAGS
+  fi
+  if test "x$have_xcb_xkb" = xyes; then
+	X11_COMPOSITOR_MODULES="$X11_COMPOSITOR_MODULES xcb-xkb"
+	AC_DEFINE([HAVE_XCB_XKB], [1], [libxcb supports XKB protocol])
+  fi
+
+  PKG_CHECK_MODULES(X11_COMPOSITOR, [$X11_COMPOSITOR_MODULES])
   AC_DEFINE([BUILD_X11_COMPOSITOR], [1], [Build the X11 compositor])
-  PKG_CHECK_MODULES(X11_COMPOSITOR, [x11 x11-xcb])
 fi
 
 

src/compositor-x11.c

@@ -35,6 +35,10 @@
 #include <linux/input.h>
 
 #include <xcb/xcb.h>
+#ifdef HAVE_XCB_XKB
+#include <xcb/xkb.h>
+#endif
+
 #include <X11/Xlib.h>
 #include <X11/Xlib-xcb.h>
 
@@ -59,6 +63,8 @@ struct x11_compositor {
 	struct wl_array		 keys;
 	struct wl_event_source	*xcb_source;
 	struct xkb_keymap	*xkb_keymap;
+	unsigned int		 has_xkb;
+	uint8_t			 xkb_event_base;
 	struct {
 		xcb_atom_t		 wm_protocols;
 		xcb_atom_t		 wm_normal_hints;
@@ -132,6 +138,31 @@ x11_compositor_get_keymap(struct x11_compositor *c)
 	return ret;
 }
 
+static void
+x11_compositor_setup_xkb(struct x11_compositor *c)
+{
+#ifndef HAVE_XCB_XKB
+	weston_log("XCB-XKB not available during build\n");
+	c->has_xkb = 0;
+	c->xkb_event_base = 0;
+	return;
+#else
+	const xcb_query_extension_reply_t *ext;
+
+	c->has_xkb = 0;
+	c->xkb_event_base = 0;
+
+	ext = xcb_get_extension_data(c->conn, &xcb_xkb_id);
+	if (!ext) {
+		weston_log("XKB extension not available on host X11 server\n");
+		return;
+	}
+	c->xkb_event_base = ext->first_event;
+
+	c->has_xkb = 1;
+#endif
+}
+
 static int
 x11_input_create(struct x11_compositor *c, int no_input)
 {
@@ -151,6 +182,8 @@ x11_input_create(struct x11_compositor *c, int no_input)
 
 	weston_seat_init_pointer(&input->base);
 
+	x11_compositor_setup_xkb(c);
+
 	keymap = x11_compositor_get_keymap(c);
 	weston_seat_init_keyboard(&input->base, keymap);
 	if (keymap)