[people/ms/u-boot.git] / common / menu.c

/*
 * Copyright 2010-2011 Calxeda, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <common.h>
#include <malloc.h>
#include <errno.h>
#include <linux/list.h>

#include "menu.h"

/*
 * Internally, each item in a menu is represented by a struct menu_item.
 *
 * These items will be alloc'd and initialized by menu_item_add and destroyed
 * by menu_item_destroy, and the consumer of the interface never sees that
 * this struct is used at all.
 */
struct menu_item {
	char *key;
	void *data;
	struct list_head list;
};

/*
 * The menu is composed of a list of items along with settings and callbacks
 * provided by the user. An incomplete definition of this struct is available
 * in menu.h, but the full definition is here to prevent consumers from
 * relying on its contents.
 */
struct menu {
	struct menu_item *default_item;
	int timeout;
	char *title;
	int prompt;
	void (*item_data_print)(void *);
	struct list_head items;
};

/*
 * An iterator function for menu items. callback will be called for each item
 * in m, with m, a pointer to the item, and extra being passed to callback. If
 * callback returns a value other than NULL, iteration stops and the value
 * return by callback is returned from menu_items_iter.  This allows it to be
 * used for search type operations. It is also safe for callback to remove the
 * item from the list of items.
 */
static inline void *menu_items_iter(struct menu *m,
		void *(*callback)(struct menu *, struct menu_item *, void *),
		void *extra)
{
	struct list_head *pos, *n;
	struct menu_item *item;
	void *ret;

	list_for_each_safe(pos, n, &m->items) {
		item = list_entry(pos, struct menu_item, list);

		ret = callback(m, item, extra);

		if (ret)
			return ret;
	}

	return NULL;
}

/*
 * Print a menu_item. If the consumer provided an item_data_print function
 * when creating the menu, call it with a pointer to the item's private data.
 * Otherwise, print the key of the item.
 */
static inline void *menu_item_print(struct menu *m,
				struct menu_item *item,
				void *extra)
{
	if (!m->item_data_print) {
		puts(item->key);
		putc('\n');
	} else {
		m->item_data_print(item->data);
	}

	return NULL;
}

/*
 * Free the memory used by a menu item. This includes the memory used by its
 * key.
 */
static inline void *menu_item_destroy(struct menu *m,
				struct menu_item *item,
				void *extra)
{
	if (item->key)
		free(item->key);

	free(item);

	return NULL;
}

void __menu_display_statusline(struct menu *m)
{
	return;
}
void menu_display_statusline(struct menu *m)
	__attribute__ ((weak, alias("__menu_display_statusline")));

/*
 * Display a menu so the user can make a choice of an item. First display its
 * title, if any, and then each item in the menu.
 */
static inline void menu_display(struct menu *m)
{
	if (m->title) {
		puts(m->title);
		putc('\n');
	}
	menu_display_statusline(m);

	menu_items_iter(m, menu_item_print, NULL);
}

/*
 * Check if an item's key matches a provided string, pointed to by extra. If
 * extra is NULL, an item with a NULL key will match. Otherwise, the item's
 * key has to match according to strcmp.
 *
 * This is called via menu_items_iter, so it returns a pointer to the item if
 * the key matches, and returns NULL otherwise.
 */
static inline void *menu_item_key_match(struct menu *m,
			struct menu_item *item, void *extra)
{
	char *item_key = extra;

	if (!item_key || !item->key) {
		if (item_key == item->key)
			return item;

		return NULL;
	}

	if (strcmp(item->key, item_key) == 0)
		return item;

	return NULL;
}

/*
 * Find the first item with a key matching item_key, if any exists.
 */
static inline struct menu_item *menu_item_by_key(struct menu *m,
							char *item_key)
{
	return menu_items_iter(m, menu_item_key_match, item_key);
}

/*
 * Set *choice to point to the default item's data, if any default item was
 * set, and returns 1. If no default item was set, returns -ENOENT.
 */
static inline int menu_default_choice(struct menu *m, void **choice)
{
	if (m->default_item) {
		*choice = m->default_item->data;
		return 1;
	}

	return -ENOENT;
}

/*
 * Displays the menu and asks the user to choose an item. *choice will point
 * to the private data of the item the user chooses. The user makes a choice
 * by inputting a string matching the key of an item. Invalid choices will
 * cause the user to be prompted again, repeatedly, until the user makes a
 * valid choice. The user can exit the menu without making a choice via ^c.
 *
 * Returns 1 if the user made a choice, or -EINTR if they bail via ^c.
 */
static inline int menu_interactive_choice(struct menu *m, void **choice)
{
	char cbuf[CONFIG_SYS_CBSIZE];
	struct menu_item *choice_item = NULL;
	int readret;

	while (!choice_item) {
		cbuf[0] = '\0';

		menu_display(m);

		readret = readline_into_buffer("Enter choice: ", cbuf,
				m->timeout / 10);

		if (readret >= 0) {
			choice_item = menu_item_by_key(m, cbuf);

			if (!choice_item) {
				printf("%s not found\n", cbuf);
				m->timeout = 0;
			}
		} else
			return menu_default_choice(m, choice);
	}

	*choice = choice_item->data;

	return 1;
}

/*
 * menu_default_set() - Sets the default choice for the menu. This is safe to
 * call more than once on a menu.
 *
 * m - Points to a menu created by menu_create().
 *
 * item_key - Points to a string that, when compared using strcmp, matches the
 * key for an existing item in the menu.
 *
 * Returns 1 if successful, -EINVAL if m is NULL, or -ENOENT if no item with a
 * key matching item_key is found.
 */
int menu_default_set(struct menu *m, char *item_key)
{
	struct menu_item *item;

	if (!m)
		return -EINVAL;

	item = menu_item_by_key(m, item_key);

	if (!item)
		return -ENOENT;

	m->default_item = item;

	return 1;
}

/*
 * menu_get_choice() - Returns the user's selected menu entry, or the default
 * if the menu is set to not prompt or the timeout expires. This is safe to
 * call more than once.
 *
 * m - Points to a menu created by menu_create().
 *
 * choice - Points to a location that will store a pointer to the selected
 * menu item. If no item is selected or there is an error, no value will be
 * written at the location it points to.
 *
 * Returns 1 if successful, -EINVAL if m or choice is NULL, -ENOENT if no
 * default has been set and the menu is set to not prompt or the timeout
 * expires, or -EINTR if the user exits the menu via ^c.
 */
int menu_get_choice(struct menu *m, void **choice)
{
	if (!m || !choice)
		return -EINVAL;

	if (!m->prompt)
		return menu_default_choice(m, choice);

	return menu_interactive_choice(m, choice);
}

/*
 * menu_item_add() - Adds or replaces a menu item. Note that this replaces the
 * data of an item if it already exists, but doesn't change the order of the
 * item.
 *
 * m - Points to a menu created by menu_create().
 *
 * item_key - Points to a string that will uniquely identify the item.  The
 * string will be copied to internal storage, and is safe to discard after
 * passing to menu_item_add.
 *
 * item_data - An opaque pointer associated with an item. It is never
 * dereferenced internally, but will be passed to the item_data_print, and
 * will be returned from menu_get_choice if the menu item is selected.
 *
 * Returns 1 if successful, -EINVAL if m is NULL, or -ENOMEM if there is
 * insufficient memory to add the menu item.
 */
int menu_item_add(struct menu *m, char *item_key, void *item_data)
{
	struct menu_item *item;

	if (!m)
		return -EINVAL;

	item = menu_item_by_key(m, item_key);

	if (item) {
		item->data = item_data;
		return 1;
	}

	item = malloc(sizeof *item);
	if (!item)
		return -ENOMEM;

	item->key = strdup(item_key);

	if (!item->key) {
		free(item);
		return -ENOMEM;
	}

	item->data = item_data;

	list_add_tail(&item->list, &m->items);

	return 1;
}

/*
 * menu_create() - Creates a menu handle with default settings
 *
 * title - If not NULL, points to a string that will be displayed before the
 * list of menu items. It will be copied to internal storage, and is safe to
 * discard after passing to menu_create().
 *
 * timeout - A delay in seconds to wait for user input. If 0, timeout is
 * disabled, and the default choice will be returned unless prompt is 1.
 *
 * prompt - If 0, don't ask for user input unless there is an interrupted
 * timeout. If 1, the user will be prompted for input regardless of the value
 * of timeout.
 *
 * item_data_print - If not NULL, will be called for each item when the menu
 * is displayed, with the pointer to the item's data passed as the argument.
 * If NULL, each item's key will be printed instead.  Since an item's key is
 * what must be entered to select an item, the item_data_print function should
 * make it obvious what the key for each entry is.
 *
 * Returns a pointer to the menu if successful, or NULL if there is
 * insufficient memory available to create the menu.
 */
struct menu *menu_create(char *title, int timeout, int prompt,
				void (*item_data_print)(void *))
{
	struct menu *m;

	m = malloc(sizeof *m);

	if (!m)
		return NULL;

	m->default_item = NULL;
	m->prompt = prompt;
	m->timeout = timeout;
	m->item_data_print = item_data_print;

	if (title) {
		m->title = strdup(title);
		if (!m->title) {
			free(m);
			return NULL;
		}
	} else
		m->title = NULL;


	INIT_LIST_HEAD(&m->items);

	return m;
}

/*
 * menu_destroy() - frees the memory used by a menu and its items.
 *
 * m - Points to a menu created by menu_create().
 *
 * Returns 1 if successful, or -EINVAL if m is NULL.
 */
int menu_destroy(struct menu *m)
{
	if (!m)
		return -EINVAL;

	menu_items_iter(m, menu_item_destroy, NULL);

	if (m->title)
		free(m->title);

	free(m);

	return 1;
}
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');
d887ad54 WD	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
e0611dd9 HS	116	void __menu_display_statusline(struct menu *m)
	117	{
	118	return;
	119	}
	120	void menu_display_statusline(struct menu *m)
	121	__attribute__ ((weak, alias("__menu_display_statusline")));
	122
b69bf52d JH	123	/*
	124	* Display a menu so the user can make a choice of an item. First display its
	125	* title, if any, and then each item in the menu.
	126	*/
	127	static inline void menu_display(struct menu *m)
	128	{
d887ad54 WD	129	if (m->title) {
	130	puts(m->title);
	131	putc('\n');
	132	}
e0611dd9	133	menu_display_statusline(m);
b69bf52d JH	134
	135	menu_items_iter(m, menu_item_print, NULL);
	136	}
	137
	138	/*
	139	* Check if an item's key matches a provided string, pointed to by extra. If
	140	* extra is NULL, an item with a NULL key will match. Otherwise, the item's
	141	* key has to match according to strcmp.
	142	*
	143	* This is called via menu_items_iter, so it returns a pointer to the item if
	144	* the key matches, and returns NULL otherwise.
	145	*/
	146	static inline void menu_item_key_match(struct menu m,
	147	struct menu_item item, void extra)
	148	{
	149	char *item_key = extra;
	150
	151	if (!item_key \|\| !item->key) {
	152	if (item_key == item->key)
	153	return item;
	154
	155	return NULL;
	156	}
	157
	158	if (strcmp(item->key, item_key) == 0)
	159	return item;
	160
	161	return NULL;
	162	}
	163
	164	/*
	165	* Find the first item with a key matching item_key, if any exists.
	166	*/
	167	static inline struct menu_item menu_item_by_key(struct menu m,
	168	char *item_key)
	169	{
	170	return menu_items_iter(m, menu_item_key_match, item_key);
	171	}
	172
b69bf52d JH	173	/*
	174	* Set *choice to point to the default item's data, if any default item was
	175	* set, and returns 1. If no default item was set, returns -ENOENT.
	176	*/
	177	static inline int menu_default_choice(struct menu m, void *choice)
	178	{
	179	if (m->default_item) {
	180	*choice = m->default_item->data;
	181	return 1;
	182	}
	183
	184	return -ENOENT;
	185	}
	186
	187	/*
	188	* Displays the menu and asks the user to choose an item. *choice will point
	189	* to the private data of the item the user chooses. The user makes a choice
	190	* by inputting a string matching the key of an item. Invalid choices will
	191	* cause the user to be prompted again, repeatedly, until the user makes a
	192	* valid choice. The user can exit the menu without making a choice via ^c.
	193	*
	194	* Returns 1 if the user made a choice, or -EINTR if they bail via ^c.
	195	*/
	196	static inline int menu_interactive_choice(struct menu m, void *choice)
	197	{
	198	char cbuf[CONFIG_SYS_CBSIZE];
	199	struct menu_item *choice_item = NULL;
	200	int readret;
	201
	202	while (!choice_item) {
	203	cbuf[0] = '\0';
	204
	205	menu_display(m);
	206
9c348311	207	readret = readline_into_buffer("Enter choice: ", cbuf,
8594753b	208	m->timeout / 10);
b69bf52d JH	209
	210	if (readret >= 0) {
	211	choice_item = menu_item_by_key(m, cbuf);
	212
fc4fa6a1	213	if (!choice_item) {
b69bf52d	214	printf("%s not found\n", cbuf);
fc4fa6a1 HS	215	m->timeout = 0;
fc4fa6a1 HS	216	}
8594753b RH	217	} else
8594753b RH	218	return menu_default_choice(m, choice);
b69bf52d JH	219	}
	220
	221	*choice = choice_item->data;
	222
	223	return 1;
	224	}
	225
	226	/*
	227	* menu_default_set() - Sets the default choice for the menu. This is safe to
	228	* call more than once on a menu.
	229	*
	230	* m - Points to a menu created by menu_create().
	231	*
	232	* item_key - Points to a string that, when compared using strcmp, matches the
	233	* key for an existing item in the menu.
	234	*
	235	* Returns 1 if successful, -EINVAL if m is NULL, or -ENOENT if no item with a
	236	* key matching item_key is found.
	237	*/
	238	int menu_default_set(struct menu m, char item_key)
	239	{
	240	struct menu_item *item;
	241
	242	if (!m)
	243	return -EINVAL;
	244
	245	item = menu_item_by_key(m, item_key);
	246
	247	if (!item)
	248	return -ENOENT;
	249
	250	m->default_item = item;
	251
	252	return 1;
	253	}
	254
	255	/*
	256	* menu_get_choice() - Returns the user's selected menu entry, or the default
b41bc5a8 JH	257	* if the menu is set to not prompt or the timeout expires. This is safe to
b41bc5a8 JH	258	* call more than once.
b69bf52d JH	259	*
	260	* m - Points to a menu created by menu_create().
	261	*
	262	* choice - Points to a location that will store a pointer to the selected
	263	* menu item. If no item is selected or there is an error, no value will be
	264	* written at the location it points to.
	265	*
	266	* Returns 1 if successful, -EINVAL if m or choice is NULL, -ENOENT if no
b41bc5a8 JH	267	* default has been set and the menu is set to not prompt or the timeout
b41bc5a8 JH	268	* expires, or -EINTR if the user exits the menu via ^c.
b69bf52d JH	269	*/
	270	int menu_get_choice(struct menu m, void *choice)
	271	{
	272	if (!m \|\| !choice)
	273	return -EINVAL;
	274
8594753b	275	if (!m->prompt)
b69bf52d JH	276	return menu_default_choice(m, choice);
	277
	278	return menu_interactive_choice(m, choice);
	279	}
	280
	281	/*
	282	* menu_item_add() - Adds or replaces a menu item. Note that this replaces the
	283	* data of an item if it already exists, but doesn't change the order of the
	284	* item.
	285	*
	286	* m - Points to a menu created by menu_create().
	287	*
	288	* item_key - Points to a string that will uniquely identify the item. The
	289	* string will be copied to internal storage, and is safe to discard after
	290	* passing to menu_item_add.
	291	*
	292	* item_data - An opaque pointer associated with an item. It is never
	293	* dereferenced internally, but will be passed to the item_data_print, and
	294	* will be returned from menu_get_choice if the menu item is selected.
	295	*
	296	* Returns 1 if successful, -EINVAL if m is NULL, or -ENOMEM if there is
	297	* insufficient memory to add the menu item.
	298	*/
	299	int menu_item_add(struct menu m, char item_key, void *item_data)
	300	{
	301	struct menu_item *item;
	302
	303	if (!m)
	304	return -EINVAL;
	305
	306	item = menu_item_by_key(m, item_key);
	307
	308	if (item) {
	309	item->data = item_data;
	310	return 1;
	311	}
	312
	313	item = malloc(sizeof *item);
	314	if (!item)
	315	return -ENOMEM;
	316
	317	item->key = strdup(item_key);
	318
	319	if (!item->key) {
	320	free(item);
	321	return -ENOMEM;
	322	}
	323
	324	item->data = item_data;
	325
	326	list_add_tail(&item->list, &m->items);
	327
	328	return 1;
	329	}
	330
	331	/*
	332	* menu_create() - Creates a menu handle with default settings
	333	*
	334	* title - If not NULL, points to a string that will be displayed before the
	335	* list of menu items. It will be copied to internal storage, and is safe to
	336	* discard after passing to menu_create().
	337	*
b41bc5a8 JH	338	* timeout - A delay in seconds to wait for user input. If 0, timeout is
	339	* disabled, and the default choice will be returned unless prompt is 1.
	340	*
	341	* prompt - If 0, don't ask for user input unless there is an interrupted
	342	* timeout. If 1, the user will be prompted for input regardless of the value
	343	* of timeout.
b69bf52d JH	344	*
	345	* item_data_print - If not NULL, will be called for each item when the menu
	346	* is displayed, with the pointer to the item's data passed as the argument.
	347	* If NULL, each item's key will be printed instead. Since an item's key is
	348	* what must be entered to select an item, the item_data_print function should
	349	* make it obvious what the key for each entry is.
	350	*
	351	* Returns a pointer to the menu if successful, or NULL if there is
	352	* insufficient memory available to create the menu.
	353	*/
b41bc5a8	354	struct menu menu_create(char title, int timeout, int prompt,
b69bf52d JH	355	void (item_data_print)(void ))
	356	{
	357	struct menu *m;
	358
	359	m = malloc(sizeof *m);
	360
	361	if (!m)
	362	return NULL;
	363
	364	m->default_item = NULL;
	365	m->prompt = prompt;
b41bc5a8	366	m->timeout = timeout;
b69bf52d JH	367	m->item_data_print = item_data_print;
	368
	369	if (title) {
	370	m->title = strdup(title);
	371	if (!m->title) {
	372	free(m);
	373	return NULL;
	374	}
	375	} else
	376	m->title = NULL;
	377
	378
	379	INIT_LIST_HEAD(&m->items);
	380
	381	return m;
	382	}
	383
	384	/*
	385	* menu_destroy() - frees the memory used by a menu and its items.
	386	*
	387	* m - Points to a menu created by menu_create().
	388	*
	389	* Returns 1 if successful, or -EINVAL if m is NULL.
	390	*/
	391	int menu_destroy(struct menu *m)
	392	{
	393	if (!m)
	394	return -EINVAL;
	395
	396	menu_items_iter(m, menu_item_destroy, NULL);
	397
	398	if (m->title)
	399	free(m->title);
	400
	401	free(m);
	402
	403	return 1;
	404	}