Harden DWM plugins against X11 stacking/keyboard grab races and speed up QMI status

src/sxmo-dmenu/dmenu.c

@@ -475,19 +475,21 @@ grabfocus(void)
 static void
 grabkeyboard(void)
 {
-  struct timespec ts = { .tv_sec = 0, .tv_nsec = 2000000 };
+  struct timespec ts = { .tv_sec = 0, .tv_nsec = 3000000 };
   Window grabwin;
   int i;
 
   if (embed || managed)
     return;
   grabwin = daemon_mode ? win : DefaultRootWindow(dpy);
-  for (i = 0; i < 25; i++) {
+  for (i = 0; i < 40; i++) {
     if (XGrabKeyboard(dpy, grabwin, True, GrabModeAsync,
                       GrabModeAsync, CurrentTime) == GrabSuccess)
-      return;
+      break;
     nanosleep(&ts, NULL);
   }
+  if (win)
+    XSetInputFocus(dpy, win, RevertToPointerRoot, CurrentTime);
 }
 
 static void
@@ -2385,6 +2387,46 @@ open_builtin_menu(const char *menu_name, int keep_idx)
   show_menu();
 }
 
+static int
+any_other_plugin_active(void)
+{
+  static const char *pid_files[] = {
+    "xdrawer.pid",
+    "xdialer.pid",
+    "xcalllog.pid",
+    "xcallscreen.pid",
+    "xcontacts.pid",
+    "xsms.pid",
+    "xfiles.pid",
+    "xcamera.pid",
+    "xthemes.pid",
+    "xmodem.pid",
+    "xnetworks.pid",
+    "xringtones.pid",
+    "xwallpapers.pid",
+  };
+  const char *rdir = getenv("XDG_RUNTIME_DIR");
+  const char *base = (rdir && rdir[0]) ? rdir : "/run/user/10000";
+  for (size_t i = 0; i < LENGTH(pid_files); i++) {
+    char ppath[256];
+    snprintf(ppath, sizeof(ppath), "%s/%s", base, pid_files[i]);
+    if (access(ppath, F_OK) != 0)
+      snprintf(ppath, sizeof(ppath), "/tmp/%s", pid_files[i]);
+    if (access(ppath, F_OK) == 0) {
+      FILE *pf = fopen(ppath, "r");
+      if (pf) {
+        int pid = -1;
+        if (fscanf(pf, "%d", &pid) == 1 && pid > 0 && kill(pid, 0) == 0) {
+          fclose(pf);
+          return 1;
+        }
+        fclose(pf);
+      }
+    }
+  }
+  return 0;
+}
+
 static void
 close_other_active_plugins(void)
 {
@@ -2639,6 +2681,8 @@ show_menu(void)
   soft_deadline = 0;
 
   if (!menu_active) {
+    menu_active = 1;
+    mark_menu_active(1);
     close_other_active_plugins();
     prevfocuswin = None;
     Window fw = None;
@@ -2654,8 +2698,6 @@ show_menu(void)
     read_softkey_state(&init_soft_mask, &init_soft_ms);
     start_ignore = dmenu_now_ms() + 180;
     initial_released = (query_trigger_keys_down() == 0);
-    menu_active = 1;
-    mark_menu_active(1);
     drawmenu();
     XMapRaised(dpy, win);
     drawmenu();
@@ -2666,11 +2708,13 @@ show_menu(void)
       XSetICFocus(xic);
     XFlush(dpy);
   } else {
+    close_other_active_plugins();
     init_soft_mask = 0;
     init_soft_ms = 0;
     start_ignore = dmenu_now_ms() + 60;
     initial_released = (query_trigger_keys_down() == 0);
     XRaiseWindow(dpy, win);
+    grabkeyboard();
     drawmenu();
     if (xic && engage_ime)
       XSetICFocus(xic);
@@ -2975,6 +3019,19 @@ process_x11_events(void)
       if (ev.xexpose.count == 0 && (menu_active || !daemon_mode))
         drw_map(drw, win, 0, 0, mw, mh);
       break;
+    case VisibilityNotify:
+      if (ev.xvisibility.state != VisibilityUnobscured &&
+          (menu_active || !daemon_mode)) {
+        if (any_other_plugin_active()) {
+          if (daemon_mode)
+            cancel_session();
+        } else {
+          XRaiseWindow(dpy, win);
+          grabkeyboard();
+          drw_map(drw, win, 0, 0, mw, mh);
+        }
+      }
+      break;
     case FocusIn:
       if (menu_active || !daemon_mode) {
         if (!daemon_mode && ev.xfocus.window != win)
@@ -3186,7 +3243,7 @@ setup(int map_immediately)
 
   swa.override_redirect = managed ? False : True;
   swa.background_pixel = scheme[SchemeNorm][ColBg].pixel;
-  swa.event_mask = ExposureMask | KeyPressMask | KeyReleaseMask | ButtonPressMask | ButtonReleaseMask | ButtonMotionMask;
+  swa.event_mask = ExposureMask | KeyPressMask | KeyReleaseMask | ButtonPressMask | ButtonReleaseMask | ButtonMotionMask | VisibilityChangeMask;
   win = XCreateWindow(dpy, parentwin, x, y, mw, mh, border_width,
                       CopyFromParent, CopyFromParent, CopyFromParent,
                       CWOverrideRedirect | CWBackPixel | CWEventMask, &swa);