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 18U-boot provides a set of interfaces for creating and using simple, text 19based menus. Menus are displayed as lists of labeled entries on the 20console, and an entry can be selected by entering its label. 21 22To use the menu code, enable CONFIG_MENU, and include "menu.h" where 23the interfaces should be available. 24 25Menus are composed of items. Each item has a key used to identify it in 26the menu, and an opaque pointer to data controlled by the consumer. 27 28If you want to show a menu, instead starting the shell, define 29CONFIG_MENU_SHOW. You have to code the int menu_show(int bootdelay) 30function, which handle your menu. This function returns the remaining 31bootdelay. 32 33Interfaces 34---------- 35#include "menu.h" 36 37/* 38 * Consumers of the menu interfaces will use a struct menu * as the 39 * handle for a menu. struct menu is only fully defined in menu.c, 40 * preventing consumers of the menu interfaces from accessing its 41 * contents directly. 42 */ 43struct menu; 44 45/* 46 * NOTE: See comments in common/menu.c for more detailed documentation on 47 * these interfaces. 48 */ 49 50/* 51 * menu_create() - Creates a menu handle with default settings 52 */ 53struct menu *menu_create(char *title, int timeout, int prompt, 54 void (*item_data_print)(void *)); 55 56/* 57 * menu_item_add() - Adds or replaces a menu item 58 */ 59int menu_item_add(struct menu *m, char *item_key, void *item_data); 60 61/* 62 * menu_default_set() - Sets the default choice for the menu 63 */ 64int menu_default_set(struct menu *m, char *item_key); 65 66/* 67 * menu_get_choice() - Returns the user's selected menu entry, or the 68 * default if the menu is set to not prompt or the timeout expires. 69 */ 70int menu_get_choice(struct menu *m, void **choice); 71 72/* 73 * menu_destroy() - frees the memory used by a menu and its items. 74 */ 75int menu_destroy(struct menu *m); 76 77/* 78 * menu_display_statusline(struct menu *m); 79 * shows a statusline for every menu_display call. 80 */ 81void menu_display_statusline(struct menu *m); 82 83Example Code 84------------ 85This example creates a menu that always prompts, and allows the user 86to pick from a list of tools. The item key and data are the same. 87 88#include "menu.h" 89 90char *tools[] = { 91 "Hammer", 92 "Screwdriver", 93 "Nail gun", 94 NULL 95}; 96 97char *pick_a_tool(void) 98{ 99 struct menu *m; 100 int i; 101 char *tool = NULL; 102 103 m = menu_create("Tools", 0, 1, NULL); 104 105 for(i = 0; tools[i]; i++) { 106 if (menu_item_add(m, tools[i], tools[i]) != 1) { 107 printf("failed to add item!"); 108 menu_destroy(m); 109 return NULL; 110 } 111 } 112 113 if (menu_get_choice(m, (void **)&tool) != 1) 114 printf("Problem picking tool!\n"); 115 116 menu_destroy(m); 117 118 return tool; 119} 120 121void caller(void) 122{ 123 char *tool = pick_a_tool(); 124 125 if (tool) { 126 printf("picked a tool: %s\n", tool); 127 use_tool(tool); 128 } 129} 130