Don't call map_win() in add_win()

Only case where you want to map window in add_win() is during compton
startup, when compton is registering existing windows. Otherwise,
add_win() is always called for newly created windows, so there will
always be a MapNotify coming up for that window. If we map newly created
windows in add_win(), we will try to map it a second time when the MapNotify
arrives.

So, just don't call map_win() from add_win(). For compton startup, we
explicitly call map_win() after calling add_win() in session_init.

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>

src/compton.c

@@ -1240,7 +1240,7 @@ ev_destroy_notify(session_t *ps, xcb_destroy_notify_event_t *ev) {
 
 inline static void
 ev_map_notify(session_t *ps, xcb_map_notify_event_t *ev) {
-  map_win(ps, ev->window);
+  map_win_by_id(ps, ev->window);
   // FocusIn/Out may be ignored when the window is unmapped, so we must
   // recheck focus here
   if (ps->o.track_focus) {
@@ -2771,6 +2771,12 @@ session_init(int argc, char **argv, Display *dpy, const char *config_file,
       add_win(ps, children[i], i ? children[i-1] : XCB_NONE);
     }
 
+    for (win *i = ps->list; i; i = i->next) {
+      if (i->a.map_state == XCB_MAP_STATE_VIEWABLE) {
+        map_win(ps, i);
+      }
+    }
+
     free(reply);
     log_trace("Initial stack:");
     for (win *c = ps->list; c; c = c->next) {

src/compton.h

@@ -41,8 +41,6 @@ find_client_win(session_t *ps, xcb_window_t w);
 
 win *find_toplevel2(session_t *ps, xcb_window_t wid);
 
-void map_win(session_t *ps, xcb_window_t id);
-
 /**
  * Subtract two unsigned long values.
  *

src/win.c

@@ -945,10 +945,6 @@ void add_win(session_t *ps, xcb_window_t id, xcb_window_t prev) {
     cdbus_ev_win_added(ps, new);
   }
 #endif
-
-  if (new->a.map_state == XCB_MAP_STATE_VIEWABLE) {
-    map_win(ps, id);
-  }
   return;
 }
 
@@ -1547,29 +1543,16 @@ void win_update_screen(session_t *ps, win *w) {
 void configure_win(session_t *, xcb_configure_notify_event_t *);
 
 /// Map an already registered window
-void
-map_win(session_t *ps, xcb_window_t id) {
-  // Unmap overlay window if it got mapped but we are currently not
-  // in redirected state.
-  if (ps->overlay && id == ps->overlay && !ps->redirected) {
-    log_debug("Overlay is mapped while we are not redirected");
-    auto e = xcb_request_check(ps->c, xcb_unmap_window(ps->c, ps->overlay));
-    if (e) {
-      log_error("Failed to unmap the overlay window");
-      free(e);
-    }
-    // We don't track the overlay window, so we can return
-    return;
-  }
+void map_win(session_t *ps, win *w) {
+  assert(w);
 
-  win *w = find_win(ps, id);
   // Don't care about window mapping if it's an InputOnly window
   // Also, try avoiding mapping a window twice
-  if (!w || w->a._class == XCB_WINDOW_CLASS_INPUT_ONLY) {
+  if (w->a._class == XCB_WINDOW_CLASS_INPUT_ONLY) {
     return;
   }
 
-  log_debug("Mapping (%#010x \"%s\")", id, w->name);
+  log_debug("Mapping (%#010x \"%s\")", w->id, w->name);
 
   if (w->state != WSTATE_UNMAPPED && w->state != WSTATE_UNMAPPING) {
     log_warn("Mapping an already mapped window");
@@ -1586,12 +1569,12 @@ map_win(session_t *ps, xcb_window_t id) {
 
   // Set window event mask before reading properties so that no property
   // changes are lost
-  xcb_change_window_attributes(ps->c, id, XCB_CW_EVENT_MASK,
-      (const uint32_t[]) { determine_evmask(ps, id, WIN_EVMODE_FRAME) });
+  xcb_change_window_attributes(ps->c, w->id, XCB_CW_EVENT_MASK,
+      (const uint32_t[]) { determine_evmask(ps, w->id, WIN_EVMODE_FRAME) });
 
   // Notify compton when the shape of a window changes
   if (ps->shape_exists) {
-    xcb_shape_select_input(ps->c, id, 1);
+    xcb_shape_select_input(ps->c, w->id, 1);
   }
 
   // Update window mode here to check for ARGB windows
@@ -1659,5 +1642,27 @@ map_win(session_t *ps, xcb_window_t id) {
   }
 }
 
+void map_win_by_id(session_t *ps, xcb_window_t id) {
+  // Unmap overlay window if it got mapped but we are currently not
+  // in redirected state.
+  if (ps->overlay && id == ps->overlay && !ps->redirected) {
+    log_debug("Overlay is mapped while we are not redirected");
+    auto e = xcb_request_check(ps->c, xcb_unmap_window(ps->c, ps->overlay));
+    if (e) {
+      log_error("Failed to unmap the overlay window");
+      free(e);
+    }
+    // We don't track the overlay window, so we can return
+    return;
+  }
+
+  win *w = find_win(ps, id);
+  if (!w) {
+    return;
+  }
+
+  map_win(ps, w);
+}
+
 
 // vim: set et sw=2 :

src/win.h

@@ -359,6 +359,9 @@ void add_win(session_t *ps, xcb_window_t id, xcb_window_t prev);
 /// Unmap or destroy a window
 void unmap_win(session_t *ps, win **, bool destroy);
 
+void map_win(session_t *ps, win *w);
+void map_win_by_id(session_t *ps, xcb_window_t id);
+
 /**
  * Execute fade callback of a window if fading finished.
  */