commit 47b4177fb83a47b72d02c3b51e763d8257a0916d
author David Reveman <reveman@chromium.org> Tue Mar 27 20:36:01 2018
committer David Reveman <reveman@chromium.org> Thu Mar 29 15:10:25 2018
tree 3560f3f98791361443a070c4329149780109815c
parent ccb0edc2d5240952b9ba153042aee3d514ad1504

Prevent X11 clients from changing the size of windows in some cases.

Limit when client can change window size to when not maximized/fullscreen
or when the compositor is not resizing the window.

Bug: 825463
Change-Id: Ia52c688a69ac39bf964ad15e84938dd99188e541
Reviewed-on: https://chromium-review.googlesource.com/986263
Reviewed-by: David Reveman <reveman@chromium.org>
Tested-by: David Reveman <reveman@chromium.org>

sommelier.c

diff --git a/sommelier.c b/sommelier.c
index 4fe71fc..875b7e3 100644
--- a/sommelier.c
+++ b/sommelier.c
@@ -412,6 +412,7 @@
   int managed;
   int realized;
   int activated;
+  int allow_resize;
   xcb_window_t transient_for;
   int decorated;
   char *name;
@@ -940,12 +941,15 @@
     window->next_config.values[i++] = 0;
   }
 
+  window->allow_resize = 1;
   wl_array_for_each(state, states) {
     if (*state == ZXDG_TOPLEVEL_V6_STATE_FULLSCREEN) {
+      window->allow_resize = 0;
       window->next_config.states[i++] =
           window->xwl->atoms[ATOM_NET_WM_STATE_FULLSCREEN].value;
     }
     if (*state == ZXDG_TOPLEVEL_V6_STATE_MAXIMIZED) {
+      window->allow_resize = 0;
       window->next_config.states[i++] =
           window->xwl->atoms[ATOM_NET_WM_STATE_MAXIMIZED_VERT].value;
       window->next_config.states[i++] =
@@ -953,6 +957,8 @@
     }
     if (*state == ZXDG_TOPLEVEL_V6_STATE_ACTIVATED)
       activated = 1;
+    if (*state == ZXDG_TOPLEVEL_V6_STATE_RESIZING)
+      window->allow_resize = 0;
   }
 
   if (activated != window->activated) {
@@ -4282,6 +4288,7 @@
   window->managed = 0;
   window->realized = 0;
   window->activated = 0;
+  window->allow_resize = 1;
   window->transient_for = XCB_WINDOW_NONE;
   window->decorated = 0;
   window->name = NULL;
@@ -4709,10 +4716,13 @@
     window->x = event->x;
   if (event->value_mask & XCB_CONFIG_WINDOW_Y)
     window->y = event->y;
-  if (event->value_mask & XCB_CONFIG_WINDOW_WIDTH)
-    window->width = event->width;
-  if (event->value_mask & XCB_CONFIG_WINDOW_HEIGHT)
-    window->height = event->height;
+
+  if (window->allow_resize) {
+    if (event->value_mask & XCB_CONFIG_WINDOW_WIDTH)
+      window->width = event->width;
+    if (event->value_mask & XCB_CONFIG_WINDOW_HEIGHT)
+      window->height = event->height;
+  }
 
   xwl_adjust_window_size_for_screen_size(window);
   if (window->size_flags & (US_POSITION | P_POSITION))