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 char *(*item_choice)(void *), 56 void *item_choice_data); 57 58/* 59 * menu_item_add() - Adds or replaces a menu item 60 */ 61int menu_item_add(struct menu *m, char *item_key, void *item_data); 62 63/* 64 * menu_default_set() - Sets the default choice for the menu 65 */ 66int menu_default_set(struct menu *m, char *item_key); 67 68/* 69 * menu_default_choice() - Set *choice to point to the default item's data 70 */ 71int menu_default_choice(struct menu *m, void **choice); 72 73/* 74 * menu_get_choice() - Returns the user's selected menu entry, or the 75 * default if the menu is set to not prompt or the timeout expires. 76 */ 77int menu_get_choice(struct menu *m, void **choice); 78 79/* 80 * menu_destroy() - frees the memory used by a menu and its items. 81 */ 82int menu_destroy(struct menu *m); 83 84/* 85 * menu_display_statusline(struct menu *m); 86 * shows a statusline for every menu_display call. 87 */ 88void menu_display_statusline(struct menu *m); 89 90Example Code 91------------ 92This example creates a menu that always prompts, and allows the user 93to pick from a list of tools. The item key and data are the same. 94 95#include "menu.h" 96 97char *tools[] = { 98 "Hammer", 99 "Screwdriver", 100 "Nail gun", 101 NULL 102}; 103 104char *pick_a_tool(void) 105{ 106 struct menu *m; 107 int i; 108 char *tool = NULL; 109 110 m = menu_create("Tools", 0, 1, NULL); 111 112 for(i = 0; tools[i]; i++) { 113 if (menu_item_add(m, tools[i], tools[i]) != 1) { 114 printf("failed to add item!"); 115 menu_destroy(m); 116 return NULL; 117 } 118 } 119 120 if (menu_get_choice(m, (void **)&tool) != 1) 121 printf("Problem picking tool!\n"); 122 123 menu_destroy(m); 124 125 return tool; 126} 127 128void caller(void) 129{ 130 char *tool = pick_a_tool(); 131 132 if (tool) { 133 printf("picked a tool: %s\n", tool); 134 use_tool(tool); 135 } 136} 137