|  | /* | 
|  | * Copyright 2010-2011 Calxeda, Inc. | 
|  | * | 
|  | * SPDX-License-Identifier:	GPL-2.0+ | 
|  | */ | 
|  |  | 
|  | #include <common.h> | 
|  | #include <cli.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 *); | 
|  | char *(*item_choice)(void *); | 
|  | void *item_choice_data; | 
|  | 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; | 
|  | } | 
|  |  | 
|  | __weak void menu_display_statusline(struct menu *m) | 
|  | { | 
|  | } | 
|  |  | 
|  | /* | 
|  | * 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. | 
|  | */ | 
|  | 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); | 
|  |  | 
|  | if (!m->item_choice) { | 
|  | readret = cli_readline_into_buffer("Enter choice: ", | 
|  | cbuf, | 
|  | m->timeout); | 
|  |  | 
|  | if (readret >= 0) { | 
|  | choice_item = menu_item_by_key(m, cbuf); | 
|  | if (!choice_item) | 
|  | printf("%s not found\n", cbuf); | 
|  | } else { | 
|  | return menu_default_choice(m, choice); | 
|  | } | 
|  | } else { | 
|  | char *key = m->item_choice(m->item_choice_data); | 
|  |  | 
|  | if (key) | 
|  | choice_item = menu_item_by_key(m, key); | 
|  | } | 
|  |  | 
|  | if (!choice_item) | 
|  | m->timeout = 0; | 
|  | } | 
|  |  | 
|  | *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. | 
|  | * | 
|  | * item_choice - If not NULL, will be called when asking the user to choose an | 
|  | * item. Returns a key string corresponding to the choosen item or NULL if | 
|  | * no item has been selected. | 
|  | * | 
|  | * item_choice_data - Will be passed as the argument to the item_choice function | 
|  | * | 
|  | * 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 *), | 
|  | char *(*item_choice)(void *), | 
|  | void *item_choice_data) | 
|  | { | 
|  | 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; | 
|  | m->item_choice = item_choice; | 
|  | m->item_choice_data = item_choice_data; | 
|  |  | 
|  | 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; | 
|  | } |