]>
Commit | Line | Data |
---|---|---|
b69bf52d JH |
1 | /* |
2 | * Copyright 2010-2011 Calxeda, Inc. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify it | |
5 | * under the terms of the GNU General Public License as published by the Free | |
6 | * Software Foundation; either version 2 of the License, or (at your option) | |
7 | * any later version. | |
8 | * | |
9 | * This program is distributed in the hope it will be useful, but WITHOUT | |
10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
12 | * more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License along with | |
15 | * this program. If not, see <http://www.gnu.org/licenses/>. | |
16 | */ | |
17 | ||
18 | #include <common.h> | |
19 | #include <malloc.h> | |
20 | #include <errno.h> | |
21 | #include <linux/list.h> | |
22 | ||
23 | #include "menu.h" | |
24 | ||
25 | /* | |
26 | * Internally, each item in a menu is represented by a struct menu_item. | |
27 | * | |
28 | * These items will be alloc'd and initialized by menu_item_add and destroyed | |
29 | * by menu_item_destroy, and the consumer of the interface never sees that | |
30 | * this struct is used at all. | |
31 | */ | |
32 | struct menu_item { | |
33 | char *key; | |
34 | void *data; | |
35 | struct list_head list; | |
36 | }; | |
37 | ||
38 | /* | |
39 | * The menu is composed of a list of items along with settings and callbacks | |
40 | * provided by the user. An incomplete definition of this struct is available | |
41 | * in menu.h, but the full definition is here to prevent consumers from | |
42 | * relying on its contents. | |
43 | */ | |
44 | struct menu { | |
45 | struct menu_item *default_item; | |
b41bc5a8 | 46 | int timeout; |
b69bf52d JH |
47 | char *title; |
48 | int prompt; | |
49 | void (*item_data_print)(void *); | |
50 | struct list_head items; | |
51 | }; | |
52 | ||
53 | /* | |
54 | * An iterator function for menu items. callback will be called for each item | |
55 | * in m, with m, a pointer to the item, and extra being passed to callback. If | |
56 | * callback returns a value other than NULL, iteration stops and the value | |
57 | * return by callback is returned from menu_items_iter. This allows it to be | |
58 | * used for search type operations. It is also safe for callback to remove the | |
59 | * item from the list of items. | |
60 | */ | |
61 | static inline void *menu_items_iter(struct menu *m, | |
62 | void *(*callback)(struct menu *, struct menu_item *, void *), | |
63 | void *extra) | |
64 | { | |
65 | struct list_head *pos, *n; | |
66 | struct menu_item *item; | |
67 | void *ret; | |
68 | ||
69 | list_for_each_safe(pos, n, &m->items) { | |
70 | item = list_entry(pos, struct menu_item, list); | |
71 | ||
72 | ret = callback(m, item, extra); | |
73 | ||
74 | if (ret) | |
75 | return ret; | |
76 | } | |
77 | ||
78 | return NULL; | |
79 | } | |
80 | ||
81 | /* | |
82 | * Print a menu_item. If the consumer provided an item_data_print function | |
83 | * when creating the menu, call it with a pointer to the item's private data. | |
84 | * Otherwise, print the key of the item. | |
85 | */ | |
86 | static inline void *menu_item_print(struct menu *m, | |
87 | struct menu_item *item, | |
88 | void *extra) | |
89 | { | |
d887ad54 | 90 | if (!m->item_data_print) { |
21574976 | 91 | puts(item->key); |
d887ad54 WD |
92 | putc('\n'); |
93 | } else { | |
b69bf52d | 94 | m->item_data_print(item->data); |
d887ad54 | 95 | } |
b69bf52d JH |
96 | |
97 | return NULL; | |
98 | } | |
99 | ||
100 | /* | |
101 | * Free the memory used by a menu item. This includes the memory used by its | |
102 | * key. | |
103 | */ | |
104 | static inline void *menu_item_destroy(struct menu *m, | |
105 | struct menu_item *item, | |
106 | void *extra) | |
107 | { | |
108 | if (item->key) | |
109 | free(item->key); | |
110 | ||
111 | free(item); | |
112 | ||
113 | return NULL; | |
114 | } | |
115 | ||
116 | /* | |
117 | * Display a menu so the user can make a choice of an item. First display its | |
118 | * title, if any, and then each item in the menu. | |
119 | */ | |
120 | static inline void menu_display(struct menu *m) | |
121 | { | |
d887ad54 WD |
122 | if (m->title) { |
123 | puts(m->title); | |
124 | putc('\n'); | |
125 | } | |
b69bf52d JH |
126 | |
127 | menu_items_iter(m, menu_item_print, NULL); | |
128 | } | |
129 | ||
130 | /* | |
131 | * Check if an item's key matches a provided string, pointed to by extra. If | |
132 | * extra is NULL, an item with a NULL key will match. Otherwise, the item's | |
133 | * key has to match according to strcmp. | |
134 | * | |
135 | * This is called via menu_items_iter, so it returns a pointer to the item if | |
136 | * the key matches, and returns NULL otherwise. | |
137 | */ | |
138 | static inline void *menu_item_key_match(struct menu *m, | |
139 | struct menu_item *item, void *extra) | |
140 | { | |
141 | char *item_key = extra; | |
142 | ||
143 | if (!item_key || !item->key) { | |
144 | if (item_key == item->key) | |
145 | return item; | |
146 | ||
147 | return NULL; | |
148 | } | |
149 | ||
150 | if (strcmp(item->key, item_key) == 0) | |
151 | return item; | |
152 | ||
153 | return NULL; | |
154 | } | |
155 | ||
156 | /* | |
157 | * Find the first item with a key matching item_key, if any exists. | |
158 | */ | |
159 | static inline struct menu_item *menu_item_by_key(struct menu *m, | |
160 | char *item_key) | |
161 | { | |
162 | return menu_items_iter(m, menu_item_key_match, item_key); | |
163 | } | |
164 | ||
b41bc5a8 JH |
165 | /* |
166 | * Wait for the user to hit a key according to the timeout set for the menu. | |
167 | * Returns 1 if the user hit a key, or 0 if the timeout expired. | |
168 | */ | |
169 | static inline int menu_interrupted(struct menu *m) | |
170 | { | |
171 | if (!m->timeout) | |
172 | return 0; | |
173 | ||
174 | if (abortboot(m->timeout/10)) | |
175 | return 1; | |
176 | ||
177 | return 0; | |
178 | } | |
179 | ||
b69bf52d JH |
180 | /* |
181 | * Checks whether or not the default menu item should be used without | |
b41bc5a8 JH |
182 | * prompting for a user choice. If the menu is set to always prompt, or the |
183 | * user hits a key during the timeout period, return 0. Otherwise, return 1 to | |
184 | * indicate we should use the default menu item. | |
b69bf52d JH |
185 | */ |
186 | static inline int menu_use_default(struct menu *m) | |
187 | { | |
b41bc5a8 | 188 | return !m->prompt && !menu_interrupted(m); |
b69bf52d JH |
189 | } |
190 | ||
191 | /* | |
192 | * Set *choice to point to the default item's data, if any default item was | |
193 | * set, and returns 1. If no default item was set, returns -ENOENT. | |
194 | */ | |
195 | static inline int menu_default_choice(struct menu *m, void **choice) | |
196 | { | |
197 | if (m->default_item) { | |
198 | *choice = m->default_item->data; | |
199 | return 1; | |
200 | } | |
201 | ||
202 | return -ENOENT; | |
203 | } | |
204 | ||
205 | /* | |
206 | * Displays the menu and asks the user to choose an item. *choice will point | |
207 | * to the private data of the item the user chooses. The user makes a choice | |
208 | * by inputting a string matching the key of an item. Invalid choices will | |
209 | * cause the user to be prompted again, repeatedly, until the user makes a | |
210 | * valid choice. The user can exit the menu without making a choice via ^c. | |
211 | * | |
212 | * Returns 1 if the user made a choice, or -EINTR if they bail via ^c. | |
213 | */ | |
214 | static inline int menu_interactive_choice(struct menu *m, void **choice) | |
215 | { | |
216 | char cbuf[CONFIG_SYS_CBSIZE]; | |
217 | struct menu_item *choice_item = NULL; | |
218 | int readret; | |
219 | ||
220 | while (!choice_item) { | |
221 | cbuf[0] = '\0'; | |
222 | ||
223 | menu_display(m); | |
224 | ||
9c348311 HS |
225 | readret = readline_into_buffer("Enter choice: ", cbuf, |
226 | m->timeout); | |
b69bf52d JH |
227 | |
228 | if (readret >= 0) { | |
229 | choice_item = menu_item_by_key(m, cbuf); | |
230 | ||
231 | if (!choice_item) | |
232 | printf("%s not found\n", cbuf); | |
233 | } else { | |
d887ad54 | 234 | puts("^C\n"); |
b69bf52d JH |
235 | return -EINTR; |
236 | } | |
237 | } | |
238 | ||
239 | *choice = choice_item->data; | |
240 | ||
241 | return 1; | |
242 | } | |
243 | ||
244 | /* | |
245 | * menu_default_set() - Sets the default choice for the menu. This is safe to | |
246 | * call more than once on a menu. | |
247 | * | |
248 | * m - Points to a menu created by menu_create(). | |
249 | * | |
250 | * item_key - Points to a string that, when compared using strcmp, matches the | |
251 | * key for an existing item in the menu. | |
252 | * | |
253 | * Returns 1 if successful, -EINVAL if m is NULL, or -ENOENT if no item with a | |
254 | * key matching item_key is found. | |
255 | */ | |
256 | int menu_default_set(struct menu *m, char *item_key) | |
257 | { | |
258 | struct menu_item *item; | |
259 | ||
260 | if (!m) | |
261 | return -EINVAL; | |
262 | ||
263 | item = menu_item_by_key(m, item_key); | |
264 | ||
265 | if (!item) | |
266 | return -ENOENT; | |
267 | ||
268 | m->default_item = item; | |
269 | ||
270 | return 1; | |
271 | } | |
272 | ||
273 | /* | |
274 | * menu_get_choice() - Returns the user's selected menu entry, or the default | |
b41bc5a8 JH |
275 | * if the menu is set to not prompt or the timeout expires. This is safe to |
276 | * call more than once. | |
b69bf52d JH |
277 | * |
278 | * m - Points to a menu created by menu_create(). | |
279 | * | |
280 | * choice - Points to a location that will store a pointer to the selected | |
281 | * menu item. If no item is selected or there is an error, no value will be | |
282 | * written at the location it points to. | |
283 | * | |
284 | * Returns 1 if successful, -EINVAL if m or choice is NULL, -ENOENT if no | |
b41bc5a8 JH |
285 | * default has been set and the menu is set to not prompt or the timeout |
286 | * expires, or -EINTR if the user exits the menu via ^c. | |
b69bf52d JH |
287 | */ |
288 | int menu_get_choice(struct menu *m, void **choice) | |
289 | { | |
290 | if (!m || !choice) | |
291 | return -EINVAL; | |
292 | ||
293 | if (menu_use_default(m)) | |
294 | return menu_default_choice(m, choice); | |
295 | ||
296 | return menu_interactive_choice(m, choice); | |
297 | } | |
298 | ||
299 | /* | |
300 | * menu_item_add() - Adds or replaces a menu item. Note that this replaces the | |
301 | * data of an item if it already exists, but doesn't change the order of the | |
302 | * item. | |
303 | * | |
304 | * m - Points to a menu created by menu_create(). | |
305 | * | |
306 | * item_key - Points to a string that will uniquely identify the item. The | |
307 | * string will be copied to internal storage, and is safe to discard after | |
308 | * passing to menu_item_add. | |
309 | * | |
310 | * item_data - An opaque pointer associated with an item. It is never | |
311 | * dereferenced internally, but will be passed to the item_data_print, and | |
312 | * will be returned from menu_get_choice if the menu item is selected. | |
313 | * | |
314 | * Returns 1 if successful, -EINVAL if m is NULL, or -ENOMEM if there is | |
315 | * insufficient memory to add the menu item. | |
316 | */ | |
317 | int menu_item_add(struct menu *m, char *item_key, void *item_data) | |
318 | { | |
319 | struct menu_item *item; | |
320 | ||
321 | if (!m) | |
322 | return -EINVAL; | |
323 | ||
324 | item = menu_item_by_key(m, item_key); | |
325 | ||
326 | if (item) { | |
327 | item->data = item_data; | |
328 | return 1; | |
329 | } | |
330 | ||
331 | item = malloc(sizeof *item); | |
332 | if (!item) | |
333 | return -ENOMEM; | |
334 | ||
335 | item->key = strdup(item_key); | |
336 | ||
337 | if (!item->key) { | |
338 | free(item); | |
339 | return -ENOMEM; | |
340 | } | |
341 | ||
342 | item->data = item_data; | |
343 | ||
344 | list_add_tail(&item->list, &m->items); | |
345 | ||
346 | return 1; | |
347 | } | |
348 | ||
349 | /* | |
350 | * menu_create() - Creates a menu handle with default settings | |
351 | * | |
352 | * title - If not NULL, points to a string that will be displayed before the | |
353 | * list of menu items. It will be copied to internal storage, and is safe to | |
354 | * discard after passing to menu_create(). | |
355 | * | |
b41bc5a8 JH |
356 | * timeout - A delay in seconds to wait for user input. If 0, timeout is |
357 | * disabled, and the default choice will be returned unless prompt is 1. | |
358 | * | |
359 | * prompt - If 0, don't ask for user input unless there is an interrupted | |
360 | * timeout. If 1, the user will be prompted for input regardless of the value | |
361 | * of timeout. | |
b69bf52d JH |
362 | * |
363 | * item_data_print - If not NULL, will be called for each item when the menu | |
364 | * is displayed, with the pointer to the item's data passed as the argument. | |
365 | * If NULL, each item's key will be printed instead. Since an item's key is | |
366 | * what must be entered to select an item, the item_data_print function should | |
367 | * make it obvious what the key for each entry is. | |
368 | * | |
369 | * Returns a pointer to the menu if successful, or NULL if there is | |
370 | * insufficient memory available to create the menu. | |
371 | */ | |
b41bc5a8 | 372 | struct menu *menu_create(char *title, int timeout, int prompt, |
b69bf52d JH |
373 | void (*item_data_print)(void *)) |
374 | { | |
375 | struct menu *m; | |
376 | ||
377 | m = malloc(sizeof *m); | |
378 | ||
379 | if (!m) | |
380 | return NULL; | |
381 | ||
382 | m->default_item = NULL; | |
383 | m->prompt = prompt; | |
b41bc5a8 | 384 | m->timeout = timeout; |
b69bf52d JH |
385 | m->item_data_print = item_data_print; |
386 | ||
387 | if (title) { | |
388 | m->title = strdup(title); | |
389 | if (!m->title) { | |
390 | free(m); | |
391 | return NULL; | |
392 | } | |
393 | } else | |
394 | m->title = NULL; | |
395 | ||
396 | ||
397 | INIT_LIST_HEAD(&m->items); | |
398 | ||
399 | return m; | |
400 | } | |
401 | ||
402 | /* | |
403 | * menu_destroy() - frees the memory used by a menu and its items. | |
404 | * | |
405 | * m - Points to a menu created by menu_create(). | |
406 | * | |
407 | * Returns 1 if successful, or -EINVAL if m is NULL. | |
408 | */ | |
409 | int menu_destroy(struct menu *m) | |
410 | { | |
411 | if (!m) | |
412 | return -EINVAL; | |
413 | ||
414 | menu_items_iter(m, menu_item_destroy, NULL); | |
415 | ||
416 | if (m->title) | |
417 | free(m->title); | |
418 | ||
419 | free(m); | |
420 | ||
421 | return 1; | |
422 | } |