- Improved Open Display function to timeout after 60 seconds, fixes p…

…ossible startup failure on boot for some distros.

kintopy/kinto.py

@@ -0,0 +1,115 @@
+#!/usr/bin/env python
+#
+# Kinto - Python implementation of Xlib
+#
+# Based on code by Stephan Sokolow
+# Source: https://gist.github.com/ssokolow/e7c9aae63fb7973e4d64cff969a78ae8
+from contextlib import contextmanager
+import Xlib
+import Xlib.display
+
+# Connect to the X server and get the root window
+disp = Xlib.display.Display()
+root = disp.screen().root
+
+# Prepare the property names we use so they can be fed into X11 APIs
+NET_ACTIVE_WINDOW = disp.intern_atom('_NET_ACTIVE_WINDOW')
+NET_WM_NAME = disp.intern_atom('_NET_WM_NAME')  # UTF-8
+WM_NAME = disp.intern_atom('WM_NAME')           # Legacy encoding
+NET_WM_CLASS = disp.intern_atom('_NET_WM_CLASS')  # UTF-8
+WM_CLASS = disp.intern_atom('WM_CLASS')
+
+last_seen = { 'xid': None, 'title': None }
+
+@contextmanager
+def window_obj(win_id):
+    """Simplify dealing with BadWindow (make it either valid or None)"""
+    window_obj = None
+    if win_id:
+        try:
+            window_obj = disp.create_resource_object('window', win_id)
+        except Xlib.error.XError:
+            pass
+    yield window_obj
+
+def get_active_window():
+    """Return a (window_obj, focus_has_changed) tuple for the active window."""
+    win_id = root.get_full_property(NET_ACTIVE_WINDOW,Xlib.X.AnyPropertyType).value[0]
+
+    focus_changed = (win_id != last_seen['xid'])
+    if focus_changed:
+        with window_obj(last_seen['xid']) as old_win:
+            if old_win:
+                old_win.change_attributes(event_mask=Xlib.X.NoEventMask)
+
+        last_seen['xid'] = win_id
+        with window_obj(win_id) as new_win:
+            if new_win:
+                new_win.change_attributes(event_mask=Xlib.X.PropertyChangeMask)
+
+    return win_id, focus_changed
+
+def _get_window_class_inner(win_obj):
+    for atom in (NET_WM_CLASS, WM_CLASS):
+        try:
+            window_class = win_obj.get_full_property(atom, 0)
+
+        except UnicodeDecodeError:  # Apparently a Debian distro package bug
+            title = "<could not decode characters>"
+        else:
+            if window_class:
+                win_class = window_class.value.split('\x00')[1]
+                if isinstance(win_class, bytes):
+                    # Apparently COMPOUND_TEXT is so arcane that this is how
+                    # tools like xprop deal with receiving it these days
+                    win_class = win_class.split('\x00')[1].decode('latin1', 'replace')
+                return win_class
+            else:
+                title = "<unnamed window>"
+
+    return "{} (XID: {})".format(title, win_obj.id)
+
+def get_window_class(win_id):
+    """Look up the window name for a given X11 window ID"""
+    if not win_id:
+        last_seen['title'] = "<no window id>"
+        return last_seen['title']
+
+    title_changed = False
+    with window_obj(win_id) as wobj:
+        if wobj:
+            win_title = _get_window_class_inner(wobj)
+            title_changed = (win_title != last_seen['title'])
+            last_seen['title'] = win_title
+
+    return last_seen['title'], title_changed
+
+def handle_xevent(event):
+    # Loop through, ignoring events until we're notified of focus/title change
+    if event.type != Xlib.X.PropertyNotify:
+        return
+
+    changed = False
+    if event.atom == NET_ACTIVE_WINDOW:
+        if get_active_window()[1]:
+            changed = changed or get_window_class(last_seen['xid'])[1]
+    elif event.atom in (NET_WM_CLASS, WM_CLASS):
+        changed = changed or get_window_class(last_seen['xid'])[1]
+
+    if changed:
+        handle_change(last_seen)
+
+def handle_change(new_state):
+    """Replace this with whatever you want to actually do"""
+    print(new_state['title'])
+
+if __name__ == '__main__':
+    # Listen for _NET_ACTIVE_WINDOW changes
+    root.change_attributes(event_mask=Xlib.X.PropertyChangeMask)
+
+    # Prime last_seen with whatever window was active when we started this
+    get_window_class(get_active_window()[0])
+    handle_change(last_seen)
+
+    while True:  # next_event() sleeps until we get an event
+        handle_xevent(disp.next_event())

kintox11/src/kintox11.c

@@ -59,9 +59,20 @@ int strcicmp(char const *a, char const *b)
 }
 
 Display* open_display(){
+  int i;
   Display* d = XOpenDisplay(NULL);
+  for (i = 0; i < 60; i++) {
+    if(d == NULL){
+      printf("fail to open X server display...\n");
+    }
+    else{
+      break;
+    }
+    sleep(1);
+  }
   if(d == NULL){
-    printf("fail to open X server display...\n");
+    printf("fail to open X server display for 1 minute...\n");
+    printf("Kintox11 is now exiting...\n");
     exit(1);
   }
   return d;
@@ -109,7 +120,7 @@ Window get_top_window(Display* d, Window start){
       XFree(children);
 
     if(xerror){
-      printf("fail to get top window: %d\n",w);
+      printf("fail to get top window: %ld\n",w);
       exit(1);
     }