diff -r e79a60b3a7cb -r 7c3ff86ee9d4 ui/common/menu.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ui/common/menu.c	Tue May 23 11:11:28 2023 +0200
@@ -0,0 +1,255 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright 2023 Olaf Wintermann. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in the
+ *      documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "menu.h"
+
+#include <stdarg.h>
+
+#include <cx/linked_list.h>
+#include <cx/array_list.h>
+
+static UiMenu *menus_begin;
+static UiMenu *menus_end;
+static CxList *current;
+
+static void add_menu(UiMenu *menu) {
+    cx_linked_list_add(
+            (void**)&menus_begin,
+            (void**)&menus_end,
+            offsetof(UiMenu, item.prev),
+            offsetof(UiMenu, item.next),
+            menu);
+}
+
+static void add_item(UiMenuItemI *item) {
+    UiMenu *menu = cxListAt(current, 0);
+    cx_linked_list_add(
+            (void**)&menu->items_begin,
+            (void**)&menu->items_end,
+            offsetof(UiMenu, item.prev),
+            offsetof(UiMenu, item.next),
+            item);
+}
+
+void ui_menu(char *label) {
+    if(!current) {
+        current = cxLinkedListCreate(cxDefaultAllocator, NULL, CX_STORE_POINTERS);
+    } else {
+        // free current menu hierarchy
+        cxListClear(current);
+    }
+    
+    // create menu
+    UiMenu *menu = malloc(sizeof(UiMenu));
+    menu->item.prev = NULL;
+    menu->item.next = NULL;
+    menu->item.type = UI_MENU;
+    
+    menu->label        = label;
+    menu->items_begin  = NULL;
+    menu->items_end    = NULL;
+    menu->parent       = NULL;    
+    
+    add_menu(menu);
+    cxListAdd(current, menu);
+}
+
+void ui_submenu(char *label) {
+    UiMenu *menu = malloc(sizeof(UiMenu));
+    menu->item.prev = NULL;
+    menu->item.next = NULL;
+    menu->item.type = UI_MENU_SUBMENU;
+    
+    menu->label       = label;
+    menu->items_begin = NULL;
+    menu->items_end   = NULL;
+    menu->parent      = NULL;
+    
+    // add submenu to current menu
+    add_item((UiMenuItemI*)menu);
+    
+    // set the submenu to current menu
+    cxListInsert(current, 0, menu);
+}
+
+void ui_submenu_end() {
+    if(current->size < 2) {
+        return;
+    }
+    cxListRemove(current, 0);
+}
+
+void ui_menuitem(char *label, ui_callback f, void *userdata) {
+    ui_menuitem_gr(label, f, userdata, -1);
+}
+
+void ui_menuitem_st(char *stockid, ui_callback f, void *userdata) {
+    ui_menuitem_stgr(stockid, f, userdata, -1);
+}
+
+void ui_menuitem_gr(char *label, ui_callback f, void *userdata, ...) {
+    if(!current) {
+        return;
+    }
+    
+    UiMenuItem *item = malloc(sizeof(UiMenuItem));
+    item->item.prev = NULL;
+    item->item.next = NULL;
+    item->item.type = UI_MENU_ITEM;
+    
+    item->label = label;
+    item->userdata = userdata;
+    item->callback = f;
+    item->groups = NULL;
+    
+    // add groups
+    va_list ap;
+    va_start(ap, userdata);
+    int group;
+    while((group = va_arg(ap, int)) != -1) {
+        if(!item->groups) {
+            item->groups = cxArrayListCreate(cxDefaultAllocator, NULL, sizeof(int), 8);
+        }
+        cxListAdd(item->groups, &group);
+    }
+    va_end(ap);
+    
+    add_item((UiMenuItemI*)item);
+}
+
+void ui_menuitem_stgr(char *stockid, ui_callback f, void *userdata, ...) {
+    if(!current) {
+        return;
+    }
+    
+    UiStMenuItem *item = malloc(sizeof(UiStMenuItem));
+    item->item.prev = NULL;
+    item->item.next = NULL;
+    item->item.type = UI_MENU_STOCK_ITEM;
+    
+    item->stockid = stockid;
+    item->userdata = userdata;
+    item->callback = f;
+    item->groups = NULL;
+    
+    // add groups
+    va_list ap;
+    va_start(ap, userdata);
+    int group;
+    while((group = va_arg(ap, int)) != -1) {
+        if(!item->groups) {
+            item->groups = cxArrayListCreate(cxDefaultAllocator, NULL, sizeof(int), 8);
+        }
+        cxListAdd(item->groups, &group);
+    }
+    va_end(ap);
+    
+    add_item((UiMenuItemI*)item);
+}
+
+void ui_menuseparator() {
+    if(!current) {
+        return;
+    }
+    
+    UiMenuItemI  *item = malloc(sizeof(UiMenuItemI));
+    item->prev = NULL;
+    item->next = NULL;
+    item->type = UI_MENU_SEPARATOR;
+    
+    add_item((UiMenuItemI*)item);
+}
+
+void ui_checkitem(char *label, ui_callback f, void *userdata) {
+    if(!current) {
+        return;
+    }
+    
+    UiCheckItem *item = malloc(sizeof(UiCheckItem));
+    item->item.prev = NULL;
+    item->item.next = NULL;
+    item->item.type = UI_MENU_CHECK_ITEM;
+    item->label = label;
+    item->callback = f;
+    item->userdata = userdata;
+    
+    add_item((UiMenuItemI*)item);
+}
+
+void ui_checkitem_nv(char *label, char *vname) {
+    if(!current) {
+        return;
+    }
+    
+    UiCheckItemNV *item = malloc(sizeof(UiCheckItemNV));
+    item->item.prev = NULL;
+    item->item.next = NULL;
+    item->item.type = UI_MENU_CHECK_ITEM_NV;
+    item->varname = vname;
+    item->label = label;
+    
+    add_item((UiMenuItemI*)item);
+}
+
+void ui_menuitem_list(UiList *items, ui_callback f, void *userdata) {
+    if(!current) {
+        return;
+    }
+    
+    UiMenuItemList *item = malloc(sizeof(UiMenuItemList));
+    item->item.prev = NULL;
+    item->item.next = NULL;
+    item->item.type = UI_MENU_ITEM_LIST;
+    item->callback = f;
+    item->userdata = userdata;
+    item->list = items;
+    
+    add_item((UiMenuItemI*)item);
+}
+
+void ui_menuitem_list_nv(const char *varname, ui_callback f, void *userdata) {
+    if(!current) {
+        return;
+    }
+    
+    UiMenuItemListNV *item = malloc(sizeof(UiMenuItemListNV));
+    item->item.prev = NULL;
+    item->item.next = NULL;
+    item->item.type = UI_MENU_ITEM_LIST;
+    item->callback = f;
+    item->userdata = userdata;
+    item->varname = varname;
+    
+    add_item((UiMenuItemI*)item);
+}
+
+
+
+UiMenu* uic_get_menu_list(void) {
+    return menus_begin;
+}