[SLOF] [PATCH 2/4] bootmenu: Gather devices and print the menu

[Thomas Huth]

Examine the aliases to get a list of possible boot devices
and print a list with all these devices.

Signed-off-by: Thomas Huth <thuth at redhat.com>
---
 lib/libbootmenu/bootmenu.c | 86 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)

diff --git a/lib/libbootmenu/bootmenu.c b/lib/libbootmenu/bootmenu.c
index d8d00cb..649e518 100644
--- a/lib/libbootmenu/bootmenu.c
+++ b/lib/libbootmenu/bootmenu.c
@@ -14,8 +14,94 @@
 
 #include <string.h>
 #include <stdio.h>
+#include <stdlib.h>
+#include <paflof.h>
 #include "bootmenu.h"
 
+#define MAX_DEVS 36        /* Enough for 10 digits + 26 letters */
+#define MAX_ALIAS_LEN 8    /* Maximum length of alias names */
+
+struct bootdev {
+	char alias[MAX_ALIAS_LEN];
+	char *path;
+};
+
+static int nr_devs;
+static struct bootdev bootdevs[MAX_DEVS];
+
+/**
+ * Look up an alias name.
+ * @return The NUL-terminated device tree path (should be released with free()
+ *         when it's not required anymore), or NULL if it can't be found.
+ */
+static char *find_alias(char *alias)
+{
+	char *path;
+	long len;
+
+	forth_push((unsigned long)alias);
+	forth_push(strlen(alias));
+	forth_eval("find-alias");
+
+	len = forth_pop();
+	if (!len)
+		return NULL;
+
+	path = malloc(len + 1);
+	memcpy(path, (void *)forth_pop(), len);
+	path[len] = '\0';
+
+	return path;
+}
+
+static void bootmenu_populate_devs(void)
+{
+	char *aliases[] = { "cdrom", "disk", "net", NULL };
+	int ai, idx;
+
+	for (ai = 0; aliases[ai] != NULL; ai++) {
+		for (idx = 0; idx <= 9; idx++) {
+			char *cur_alias = bootdevs[nr_devs].alias;
+			if (idx == 0)
+				strcpy(cur_alias, aliases[ai]);
+			else
+				sprintf(cur_alias, "%s%i", aliases[ai], idx);
+			bootdevs[nr_devs].path = find_alias(cur_alias);
+			if (!bootdevs[nr_devs].path)
+				break;
+			nr_devs += 1;
+		}
+	}
+}
+
+static void bootmenu_free_devs(void)
+{
+	while (nr_devs > 0) {
+		nr_devs -= 1;
+		free(bootdevs[nr_devs].path);
+		bootdevs[nr_devs].path = NULL;
+	}
+}
+
+static void bootmenu_show_devs(void)
+{
+	int i;
+
+	for (i = 0; i < nr_devs; i++) {
+		printf("%c) %6s : %s\n", i < 9 ? '1' + i : 'a' + i - 9,
+		       bootdevs[i].alias, bootdevs[i].path);
+	}
+}
+
 void bootmenu(void)
 {
+	bootmenu_populate_devs();
+	if (!nr_devs) {
+		puts("No available boot devices!");
+		return;
+	}
+
+	bootmenu_show_devs();
+
+	bootmenu_free_devs();
 }
-- 
1.8.3.1