use XKB extension instead of deprecated API0.4.0

1 files changed, 40 insertions, 8 deletions

diff --git a/unsaver.c b/unsaver.c
index ec502df..2cba2dc 100644
--- a/unsaver.c
+++ b/unsaver.c
@@ -17,6 +17,7 @@
 
 #include <X11/X.h>
 #include <X11/Xlib.h>
+#include <X11/XKBlib.h>
 #include <X11/extensions/XTest.h>
 
 #include <linux/joystick.h>
@@ -661,31 +662,62 @@ void connect_to_x(void) {
 	}
 }
 
-/* XXX: XKeycodeToKeysym() is deprecated. I must learn XKB. */
+/* XKeycodeToKeysym() is deprecated, hence the pragma fugliness.
+   Deprecated or not, the xmodmap command still uses it, and it
+   still works. However, XKB is the new hotness, we'll use that if
+   it's available. */
+KeySym keycode_is_mapped(XkbDescPtr xkbd, int i) {
+	if(xkbd) {
+		return XkbKeyNumGroups(xkbd, i) > 0;
+	} else {
+		/* if xkbd is NULL, the caller failed to init XKB. */
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
-KeySym get_keysym(int i) {
-	return XKeycodeToKeysym(xdisp, i, 0);
-}
+		return XKeycodeToKeysym(xdisp, i, 0) != NoSymbol;
 #pragma GCC diagnostic pop
+	}
+}
 
-/* the goggles, they do nothing! */
+/* The goggles, they do nothing!
+   Find an unused keycode in the keymap. From the shell, this would
+   be something like: xmodmap -pke|grep '= *$'|head -1 */
 void find_keycode() {
-	int i, min_code = 0, max_code = 0;
-	
+	int i, ignoreme, min_code = 0, max_code = 0;
+	int major = XkbMajorVersion, minor = XkbMinorVersion;
+	XkbDescPtr xkbd = NULL;
+
+	/* not sure any X server still running on planet Earth will lack
+	   the XKB extension, but in case I'm wrong... */
+	if(XkbQueryExtension(
+				xdisp,
+				&ignoreme,
+				&ignoreme,
+				&ignoreme,
+				&major,
+				&minor))
+	{
+		xkbd = XkbGetMap(xdisp, XkbAllClientInfoMask, XkbUseCoreKbd);
+		fprintf(stderr, "using XKB extension major %d, minor %d\n", major, minor);
+	} else {
+		fprintf(stderr, "XKB extension not supported, fall back to XKeycodeToKeysym\n");
+	}
+
 	/* man page doesn't document the return value */
 	(void)XDisplayKeycodes(xdisp, &min_code, &max_code);
 
 	if(debug) fprintf(stderr, "XDisplayKeycodes min %d, max %d\n", min_code, max_code);
 
 	for(i = min_code; i <= max_code; i++) {
-		if(get_keysym(i) == NoSymbol) {
+		if(!keycode_is_mapped(xkbd, i)) {
 			keycode = i;
 			if(debug) fprintf(stderr, "using keycode %d\n", keycode);
 			break;
 		}
 	}
 
+	if(xkbd)
+		XkbFreeKeyboard(xkbd, XkbAllClientInfoMask, 1);
+
 	if(keycode < 0) {
 		fprintf(stderr,
 				"%s: can't find a free keycode in the keymap, using %d\n",