16  * Internally, each item in a menu is represented by a struct menu_item.
46  * An iterator function for menu items. callback will be called for each item
47  * in m, with m, a pointer to the item, and extra being passed to callback. If
51  * item from the list of items.
58 	struct menu_item *item;  in menu_items_iter()  local
62 		item = list_entry(pos, struct menu_item, list);  in menu_items_iter()
64 		ret = callback(m, item, extra);  in menu_items_iter()
75  * when creating the menu, call it with a pointer to the item's private data.
76  * Otherwise, print the key of the item.
79 				struct menu_item *item,  in menu_item_print()  argument
83 		puts(item->key);  in menu_item_print()
86 		m->item_data_print(item->data);  in menu_item_print()
93  * Free the memory used by a menu item. This includes the memory used by its
97 				struct menu_item *item,  in menu_item_destroy()  argument
100 	if (item->key)  in menu_item_destroy()
101 		free(item->key);  in menu_item_destroy()
103 	free(item);  in menu_item_destroy()
113  * Display a menu so the user can make a choice of an item. First display its
114  * title, if any, and then each item in the menu.
128  * Check if an item's key matches a provided string, pointed to by extra. If
129  * extra is NULL, an item with a NULL key will match. Otherwise, the item's
132  * This is called via menu_items_iter, so it returns a pointer to the item if
136 			struct menu_item *item, void *extra)  in menu_item_key_match()  argument
140 	if (!item_key || !item->key) {  in menu_item_key_match()
141 		if (item_key == item->key)  in menu_item_key_match()
142 			return item;  in menu_item_key_match()
147 	if (strcmp(item->key, item_key) == 0)  in menu_item_key_match()
148 		return item;  in menu_item_key_match()
154  * Find the first item with a key matching item_key, if any exists.
163  * Set *choice to point to the default item's data, if any default item was
164  * set, and returns 1. If no default item was set, returns -ENOENT.
177  * Displays the menu and asks the user to choose an item. *choice will point
178  * to the private data of the item the user chooses. The user makes a choice
179  * by inputting a string matching the key of an item. Invalid choices will
234  * key for an existing item in the menu.
236  * Returns 1 if successful, -EINVAL if m is NULL, or -ENOENT if no item with a
241 	struct menu_item *item;  in menu_default_set()  local
246 	item = menu_item_by_key(m, item_key);  in menu_default_set()
248 	if (!item)  in menu_default_set()
251 	m->default_item = item;  in menu_default_set()
264  * menu item. If no item is selected or there is an error, no value will be
283  * menu_item_add() - Adds or replaces a menu item. Note that this replaces the
284  * data of an item if it already exists, but doesn't change the order of the
285  * item.
289  * item_key - Points to a string that will uniquely identify the item.  The
293  * item_data - An opaque pointer associated with an item. It is never
295  * will be returned from menu_get_choice if the menu item is selected.
298  * insufficient memory to add the menu item.
302 	struct menu_item *item;  in menu_item_add()  local
307 	item = menu_item_by_key(m, item_key);  in menu_item_add()
309 	if (item) {  in menu_item_add()
310 		item->data = item_data;  in menu_item_add()
314 	item = malloc(sizeof *item);  in menu_item_add()
315 	if (!item)  in menu_item_add()
318 	item->key = strdup(item_key);  in menu_item_add()
320 	if (!item->key) {  in menu_item_add()
321 		free(item);  in menu_item_add()
325 	item->data = item_data;  in menu_item_add()
327 	list_add_tail(&item->list, &m->items);  in menu_item_add()
346  * item_data_print - If not NULL, will be called for each item when the menu
347  * is displayed, with the pointer to the item's data passed as the argument.
348  * If NULL, each item's key will be printed instead.  Since an item's key is
349  * what must be entered to select an item, the item_data_print function should
353  * item. Returns a key string corresponding to the chosen item or NULL if
354  * no item has been selected.