menu: guard against negative sizes

For example, the size of a scene_rect for a menu item background could be
negative with:

  menu.width.max: 0
  menu.width.min: 0

diff --git a/src/menu/menu.c b/src/menu/menu.c
index 9e6734afc7a5f0530f56bfdf07b0b5f1c3639477..9ce98dc94ff561787563693e6cb8ae7c5d688cf0 100644 (file)
--- a/src/menu/menu.c
+++ b/src/menu/menu.c
@@ -174,14 +174,19 @@ item_create_scene_for_state(struct menuitem *item, float *text_color,
                icon_width = theme->menu_items_padding_x + icon_size;
        }
 
-       /* Create background */
-       int bg_width = menu->size.width
-               - 2 * theme->menu_border_width;
-       wlr_scene_rect_create(tree, bg_width, theme->menu_item_height, bg_color);
-
+       int bg_width = menu->size.width - 2 * theme->menu_border_width;
        int arrow_width = item->arrow ?
                font_width(&rc.font_menuitem, item->arrow) : 0;
-       int label_max_width = bg_width - 2 * theme->menu_items_padding_x - arrow_width - icon_width;
+       int label_max_width = bg_width - 2 * theme->menu_items_padding_x
+               - arrow_width - icon_width;
+
+       if (label_max_width <= 0) {
+               wlr_log(WLR_ERROR, "not enough space for menu contents");
+               return tree;
+       }
+
+       /* Create background */
+       wlr_scene_rect_create(tree, bg_width, theme->menu_item_height, bg_color);
 
        /* Create icon */
        bool show_app_icon = !strcmp(item->parent->id, "client-list-combined-menu")
@@ -283,9 +288,6 @@ separator_create_scene(struct menuitem *menuitem, int *item_y)
        assert(menuitem->type == LAB_MENU_SEPARATOR_LINE);
        struct menu *menu = menuitem->parent;
        struct theme *theme = menu->server->theme;
-       int bg_width = menu->size.width - 2 * theme->menu_border_width;
-       int bg_height = theme->menu_separator_line_thickness
-               + 2 * theme->menu_separator_padding_height;
 
        /* Menu item root node */
        menuitem->tree = wlr_scene_tree_create(menu->scene_tree);
@@ -295,12 +297,21 @@ separator_create_scene(struct menuitem *menuitem, int *item_y)
        /* Tree to hold background and line buffer */
        menuitem->normal_tree = wlr_scene_tree_create(menuitem->tree);
 
+       int bg_height = theme->menu_separator_line_thickness
+               + 2 * theme->menu_separator_padding_height;
+       int bg_width = menu->size.width - 2 * theme->menu_border_width;
+       int line_width = bg_width - 2 * theme->menu_separator_padding_width;
+
+       if (line_width <= 0) {
+               wlr_log(WLR_ERROR, "not enough space for menu separator");
+               goto error;
+       }
+
        /* Item background nodes */
        wlr_scene_rect_create(menuitem->normal_tree, bg_width, bg_height,
                theme->menu_items_bg_color);
 
        /* Draw separator line */
-       int line_width = bg_width - 2 * theme->menu_separator_padding_width;
        struct wlr_scene_rect *line_rect = wlr_scene_rect_create(
                menuitem->normal_tree, line_width,
                theme->menu_separator_line_thickness,
@@ -310,6 +321,7 @@ separator_create_scene(struct menuitem *menuitem, int *item_y)
        wlr_scene_node_set_position(&line_rect->node,
                theme->menu_separator_padding_width,
                theme->menu_separator_padding_height);
+error:
        wlr_scene_node_set_position(&menuitem->tree->node,
                theme->menu_border_width, *item_y);
        *item_y += bg_height;
@@ -324,7 +336,6 @@ title_create_scene(struct menuitem *menuitem, int *item_y)
        struct theme *theme = menu->server->theme;
        float *bg_color = theme->menu_title_bg_color;
        float *text_color = theme->menu_title_text_color;
-       int bg_width = menu->size.width - 2 * theme->menu_border_width;
 
        /* Menu item root node */
        menuitem->tree = wlr_scene_tree_create(menu->scene_tree);
@@ -334,6 +345,14 @@ title_create_scene(struct menuitem *menuitem, int *item_y)
        /* Tree to hold background and text buffer */
        menuitem->normal_tree = wlr_scene_tree_create(menuitem->tree);
 
+       int bg_width = menu->size.width - 2 * theme->menu_border_width;
+       int text_width = bg_width - 2 * theme->menu_items_padding_x;
+
+       if (text_width <= 0) {
+               wlr_log(WLR_ERROR, "not enough space for menu title");
+               goto error;
+       }
+
        /* Background */
        wlr_scene_rect_create(menuitem->normal_tree,
                bg_width, theme->menu_header_height, bg_color);
@@ -343,8 +362,7 @@ title_create_scene(struct menuitem *menuitem, int *item_y)
                scaled_font_buffer_create(menuitem->normal_tree);
        assert(title_font_buffer);
        scaled_font_buffer_update(title_font_buffer, menuitem->text,
-               bg_width - 2 * theme->menu_items_padding_x,
-               &rc.font_menuheader, text_color, bg_color);
+               text_width, &rc.font_menuheader, text_color, bg_color);
 
        int title_x = 0;
        switch (theme->menu_title_text_justify) {
@@ -363,7 +381,7 @@ title_create_scene(struct menuitem *menuitem, int *item_y)
        int title_y = (theme->menu_header_height - title_font_buffer->height) / 2;
        wlr_scene_node_set_position(&title_font_buffer->scene_buffer->node,
                title_x, title_y);
-
+error:
        wlr_scene_node_set_position(&menuitem->tree->node,
                theme->menu_border_width, *item_y);
        *item_y += theme->menu_header_height;