[U-Boot,v2,4/6] Add generic, reusable menu code

diff --git a/common/Makefile b/common/Makefile
index f81cff9..9b413cd 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -171,6 +171,7 @@  COBJS-$(CONFIG_CMD_KGDB) += kgdb.o kgdb_stubs.o
 COBJS-$(CONFIG_KALLSYMS) += kallsyms.o
 COBJS-$(CONFIG_LCD) += lcd.o
 COBJS-$(CONFIG_LYNXKDI) += lynxkdi.o
+COBJS-$(CONFIG_MENU) += menu.o
 COBJS-$(CONFIG_MODEM_SUPPORT) += modem.o
 COBJS-$(CONFIG_UPDATE_TFTP) += update.o
 COBJS-$(CONFIG_USB_KEYBOARD) += usb_kbd.o
diff --git a/common/menu.c b/common/menu.c
new file mode 100644
index 0000000..e92d302
--- /dev/null
+++ b/common/menu.c
@@ -0,0 +1,338 @@ 
+/*
+ * 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"
+
+struct menu_item {
+	char *key;
+	void *data;
+	struct list_head list;
+};
+
+struct menu {
+	struct menu_item *default_item;
+	int timeout;
+	char *title;
+	int prompt;
+	void (*item_data_print)(void *);
+	void (*item_data_destroy)(void *);
+	struct list_head items;
+};
+
+struct callback_with_data {
+	void *(*callback)(void *, void *);
+	void *data;
+};
+
+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;
+}
+
+static inline void *menu_item_print(struct menu *m,
+				struct menu_item *item,
+				void *extra)
+{
+	if (!m->item_data_print)
+		printf("%s:\n", item->key);
+	else
+		m->item_data_print(item->data);
+
+	return NULL;
+}
+
+static inline void *menu_item_destroy(struct menu *m,
+				struct menu_item *item,
+				void *extra)
+{
+	if (m->item_data_destroy)
+		m->item_data_destroy(item->data);
+
+	if (item->key)
+		free(item->key);
+
+	free(item);
+
+	return NULL;
+}
+
+static inline void menu_display(struct menu *m)
+{
+	if (m->title)
+		printf("%s\n", m->title);
+
+	menu_items_iter(m, menu_item_print, NULL);
+}
+
+static inline void *menu_item_key_match(struct menu *m,
+				struct menu_item *item,
+				void *key)
+{
+	if (!key || !item->key) {
+		if (key == item)
+			return item;
+
+		return NULL;
+	}
+
+	if (strcmp(item->key, key) == 0)
+		return item;
+
+	return NULL;
+}
+
+static inline struct menu_item *menu_item_by_key(struct menu *m, char *key)
+{
+	return menu_items_iter(m, menu_item_key_match, key);
+}
+
+static inline void *menu_item_data_cb(struct menu *m,
+				struct menu_item *item,
+				void *extra)
+{
+
+	struct callback_with_data *cb_data = extra;
+
+	return cb_data->callback(item->data, cb_data->data);
+}
+
+static inline int delay_for_input(int timeout)
+{
+	if (!timeout)
+		return 0;
+
+	if (abortboot(timeout/10)) {
+		printf("autoboot aborted!\n");
+		return 1;
+	}
+
+	return 0;
+}
+
+void *menu_items_data_iter(struct menu *m,
+			void *(*callback)(void *, void *),
+			void *extra)
+{
+	struct callback_with_data cb_data;
+
+	if (!m || !callback)
+		return NULL;
+
+	cb_data.callback = callback;
+	cb_data.data = extra;
+
+	return menu_items_iter(m, menu_item_data_cb, &cb_data);
+}
+
+int menu_should_prompt(struct menu *m)
+{
+	if (!m)
+		return -EINVAL;
+
+	return m->prompt || delay_for_input(m->timeout);
+}
+
+int menu_default_set(struct menu *m, char *key)
+{
+	struct menu_item *item;
+
+	if (!m)
+		return -EINVAL;
+
+	item = menu_item_by_key(m, key);
+
+	if (!item)
+		return -ENOENT;
+
+	m->default_item = item;
+
+	return 1;
+}
+
+void *menu_default_choice(struct menu *m)
+{
+	if (!m)
+		return NULL;
+
+	if (m->default_item)
+		return m->default_item->data;
+
+	return NULL;
+}
+
+void *menu_user_choice(struct menu *m)
+{
+	char cbuf[CONFIG_SYS_CBSIZE];
+	struct menu_item *choice_item = NULL;
+
+	if (!m)
+		return NULL;
+
+	while (!choice_item) {
+		int readret;
+
+		cbuf[0] = '\0';
+
+		menu_display(m);
+
+		readret = readline_into_buffer("Enter choice: ", cbuf);
+
+		if (readret >= 0) {
+			choice_item = menu_item_by_key(m, cbuf);
+
+			if (!choice_item)
+				printf("%s not found\n", cbuf);
+			else
+				return choice_item->data;
+		} else {
+			printf("^C\n");
+			return NULL;
+		}
+	}
+
+	return NULL;
+}
+
+/*
+ * note that this replaces the data of an item if it already exists, but
+ * doesn't change the order of the 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) {
+		m->item_data_destroy(item->data);
+		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;
+}
+
+struct menu *menu_create(void (*item_data_print)(void *),
+			void (*item_data_destroy)(void *))
+{
+	struct menu *m;
+
+	m = malloc(sizeof *m);
+
+	if (!m)
+		return NULL;
+
+	m->default_item = NULL;
+	m->timeout = 0;
+	m->title = NULL;
+	m->prompt = 0;
+
+	m->item_data_print = item_data_print;
+	m->item_data_destroy = item_data_destroy;
+
+	INIT_LIST_HEAD(&m->items);
+
+	return m;
+}
+
+int menu_title_set(struct menu *m, char *title)
+{
+	char *new_title;
+
+	if (!m || !title)
+		return -EINVAL;
+
+	new_title = strdup(title);
+
+	if (!new_title)
+		return -ENOMEM;
+
+	if (m->title)
+		free(m->title);
+
+	m->title = new_title;
+
+	return 1;
+}
+
+void menu_destroy(struct menu *m)
+{
+	if (!m)
+		return;
+
+	menu_items_iter(m, menu_item_destroy, NULL);
+
+	if (m->title)
+		free(m->title);
+
+	free(m);
+}
+
+void menu_prompt_set(struct menu *m, int prompt)
+{
+	if (!m)
+		return;
+
+	m->prompt = prompt;
+}
+
+void menu_timeout_set(struct menu *m, int timeout)
+{
+	if (!m)
+		return;
+
+	m->timeout = timeout;
+}
diff --git a/include/menu.h b/include/menu.h
new file mode 100644
index 0000000..5ffb3b8
--- /dev/null
+++ b/include/menu.h
@@ -0,0 +1,40 @@ 
+/*
+ * 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/>.
+ */
+
+#ifndef __MENU_H__
+#define __MENU_H__
+
+struct menu;
+struct menu_item;
+
+void *menu_items_data_iter(struct menu *m,
+		void *(*callback)(void *, void *),
+		void *extra);
+
+int menu_should_prompt(struct menu *m);
+int menu_default_set(struct menu *m, char *key);
+void *menu_default_choice(struct menu *m);
+void *menu_user_choice(struct menu *m);
+int menu_item_add(struct menu *m, char *item_key, void *item_data);
+struct menu *menu_create(void (*item_data_print)(void *),
+			void (*item_data_destroy)(void *));
+int menu_title_set(struct menu *m, char *title);
+void menu_destroy(struct menu *m);
+void menu_prompt_set(struct menu *m, int prompt);
+void menu_timeout_set(struct menu *m, int timeout);
+
+#endif /* __MENU_H__ */