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git.ipfire.org Git - people/ms/u-boot.git/blob - common/menu.c
2 * Copyright 2010-2011 Calxeda, Inc.
4 * SPDX-License-Identifier: GPL-2.0+
11 #include <linux/list.h>
16 * Internally, each item in a menu is represented by a struct menu_item.
18 * These items will be alloc'd and initialized by menu_item_add and destroyed
19 * by menu_item_destroy, and the consumer of the interface never sees that
20 * this struct is used at all.
25 struct list_head list
;
29 * The menu is composed of a list of items along with settings and callbacks
30 * provided by the user. An incomplete definition of this struct is available
31 * in menu.h, but the full definition is here to prevent consumers from
32 * relying on its contents.
35 struct menu_item
*default_item
;
39 void (*item_data_print
)(void *);
40 char *(*item_choice
)(void *);
41 void *item_choice_data
;
42 struct list_head items
;
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
48 * callback returns a value other than NULL, iteration stops and the value
49 * return by callback is returned from menu_items_iter. This allows it to be
50 * used for search type operations. It is also safe for callback to remove the
51 * item from the list of items.
53 static inline void *menu_items_iter(struct menu
*m
,
54 void *(*callback
)(struct menu
*, struct menu_item
*, void *),
57 struct list_head
*pos
, *n
;
58 struct menu_item
*item
;
61 list_for_each_safe(pos
, n
, &m
->items
) {
62 item
= list_entry(pos
, struct menu_item
, list
);
64 ret
= callback(m
, item
, extra
);
74 * Print a menu_item. If the consumer provided an item_data_print function
75 * when creating the menu, call it with a pointer to the item's private data.
76 * Otherwise, print the key of the item.
78 static inline void *menu_item_print(struct menu
*m
,
79 struct menu_item
*item
,
82 if (!m
->item_data_print
) {
86 m
->item_data_print(item
->data
);
93 * Free the memory used by a menu item. This includes the memory used by its
96 static inline void *menu_item_destroy(struct menu
*m
,
97 struct menu_item
*item
,
108 __weak
void menu_display_statusline(struct menu
*m
)
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.
116 static inline void menu_display(struct menu
*m
)
122 menu_display_statusline(m
);
124 menu_items_iter(m
, menu_item_print
, NULL
);
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
130 * key has to match according to strcmp.
132 * This is called via menu_items_iter, so it returns a pointer to the item if
133 * the key matches, and returns NULL otherwise.
135 static inline void *menu_item_key_match(struct menu
*m
,
136 struct menu_item
*item
, void *extra
)
138 char *item_key
= extra
;
140 if (!item_key
|| !item
->key
) {
141 if (item_key
== item
->key
)
147 if (strcmp(item
->key
, item_key
) == 0)
154 * Find the first item with a key matching item_key, if any exists.
156 static inline struct menu_item
*menu_item_by_key(struct menu
*m
,
159 return menu_items_iter(m
, menu_item_key_match
, item_key
);
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.
166 int menu_default_choice(struct menu
*m
, void **choice
)
168 if (m
->default_item
) {
169 *choice
= m
->default_item
->data
;
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
180 * cause the user to be prompted again, repeatedly, until the user makes a
181 * valid choice. The user can exit the menu without making a choice via ^c.
183 * Returns 1 if the user made a choice, or -EINTR if they bail via ^c.
185 static inline int menu_interactive_choice(struct menu
*m
, void **choice
)
187 char cbuf
[CONFIG_SYS_CBSIZE
];
188 struct menu_item
*choice_item
= NULL
;
191 while (!choice_item
) {
196 if (!m
->item_choice
) {
197 readret
= cli_readline_into_buffer("Enter choice: ",
202 choice_item
= menu_item_by_key(m
, cbuf
);
204 printf("%s not found\n", cbuf
);
205 } else if (readret
== -1) {
206 printf("<INTERRUPT>\n");
209 return menu_default_choice(m
, choice
);
212 char *key
= m
->item_choice(m
->item_choice_data
);
215 choice_item
= menu_item_by_key(m
, key
);
222 *choice
= choice_item
->data
;
228 * menu_default_set() - Sets the default choice for the menu. This is safe to
229 * call more than once on a menu.
231 * m - Points to a menu created by menu_create().
233 * item_key - Points to a string that, when compared using strcmp, matches the
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
237 * key matching item_key is found.
239 int menu_default_set(struct menu
*m
, char *item_key
)
241 struct menu_item
*item
;
246 item
= menu_item_by_key(m
, item_key
);
251 m
->default_item
= item
;
257 * menu_get_choice() - Returns the user's selected menu entry, or the default
258 * if the menu is set to not prompt or the timeout expires. This is safe to
259 * call more than once.
261 * m - Points to a menu created by menu_create().
263 * choice - Points to a location that will store a pointer to the selected
264 * menu item. If no item is selected or there is an error, no value will be
265 * written at the location it points to.
267 * Returns 1 if successful, -EINVAL if m or choice is NULL, -ENOENT if no
268 * default has been set and the menu is set to not prompt or the timeout
269 * expires, or -EINTR if the user exits the menu via ^c.
271 int menu_get_choice(struct menu
*m
, void **choice
)
277 return menu_default_choice(m
, choice
);
279 return menu_interactive_choice(m
, choice
);
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
287 * m - Points to a menu created by menu_create().
289 * item_key - Points to a string that will uniquely identify the item. The
290 * string will be copied to internal storage, and is safe to discard after
291 * passing to menu_item_add.
293 * item_data - An opaque pointer associated with an item. It is never
294 * dereferenced internally, but will be passed to the item_data_print, and
295 * will be returned from menu_get_choice if the menu item is selected.
297 * Returns 1 if successful, -EINVAL if m is NULL, or -ENOMEM if there is
298 * insufficient memory to add the menu item.
300 int menu_item_add(struct menu
*m
, char *item_key
, void *item_data
)
302 struct menu_item
*item
;
307 item
= menu_item_by_key(m
, item_key
);
310 item
->data
= item_data
;
314 item
= malloc(sizeof *item
);
318 item
->key
= strdup(item_key
);
325 item
->data
= item_data
;
327 list_add_tail(&item
->list
, &m
->items
);
333 * menu_create() - Creates a menu handle with default settings
335 * title - If not NULL, points to a string that will be displayed before the
336 * list of menu items. It will be copied to internal storage, and is safe to
337 * discard after passing to menu_create().
339 * timeout - A delay in seconds to wait for user input. If 0, timeout is
340 * disabled, and the default choice will be returned unless prompt is 1.
342 * prompt - If 0, don't ask for user input unless there is an interrupted
343 * timeout. If 1, the user will be prompted for input regardless of the value
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
350 * make it obvious what the key for each entry is.
352 * item_choice - If not NULL, will be called when asking the user to choose an
353 * item. Returns a key string corresponding to the chosen item or NULL if
354 * no item has been selected.
356 * item_choice_data - Will be passed as the argument to the item_choice function
358 * Returns a pointer to the menu if successful, or NULL if there is
359 * insufficient memory available to create the menu.
361 struct menu
*menu_create(char *title
, int timeout
, int prompt
,
362 void (*item_data_print
)(void *),
363 char *(*item_choice
)(void *),
364 void *item_choice_data
)
368 m
= malloc(sizeof *m
);
373 m
->default_item
= NULL
;
375 m
->timeout
= timeout
;
376 m
->item_data_print
= item_data_print
;
377 m
->item_choice
= item_choice
;
378 m
->item_choice_data
= item_choice_data
;
381 m
->title
= strdup(title
);
390 INIT_LIST_HEAD(&m
->items
);
396 * menu_destroy() - frees the memory used by a menu and its items.
398 * m - Points to a menu created by menu_create().
400 * Returns 1 if successful, or -EINVAL if m is NULL.
402 int menu_destroy(struct menu
*m
)
407 menu_items_iter(m
, menu_item_destroy
, NULL
);