A new SLOF boot menu

The current SLOF boot menu heavily depends on the contents of the
"qemu,boot-list" and "qemu,boot-device"" properties in the device tree,
so that the menu entries either look very strange (when there is no
alias, see https://bugzilla.redhat.com/show_bug.cgi?id=1429832 ) or
are duplicated (https://bugzilla.redhat.com/show_bug.cgi?id=1446018).

A proper boot menu should rather show all available boot devices
instead, so this patch series introduces a new boot menu (written in
C this time) which is independent from the "qemu,boot-list/device"
properties by looking at the available aliases instead. It is now also
possible by selecting the entries with one key stroke only (you don't
have to press RETURN anymore), so this is now hopefully much more user
friendly than the old menu.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>

6 files changed, 287 insertions, 1 deletions

diff --git a/lib/Makefile b/lib/Makefile
index 6d9db66..a4d4bb2 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -11,7 +11,7 @@
 # ****************************************************************************/
 
 SUBDIRS = libc libipmi libbootmsg libbases libnvram libelf libhvcall libvirtio \
-          libusb libveth libe1k libbcm libnet
+          libusb libveth libe1k libbcm libnet libbootmenu
 
 all:  subdirs
 
diff --git a/lib/libbootmenu/Makefile b/lib/libbootmenu/Makefile
new file mode 100644
index 0000000..156bc8b
--- /dev/null
+++ b/lib/libbootmenu/Makefile
@@ -0,0 +1,49 @@
+# *****************************************************************************
+# * Copyright (c) 2004, 2008 IBM Corporation
+# * All rights reserved.
+# * This program and the accompanying materials
+# * are made available under the terms of the BSD License
+# * which accompanies this distribution, and is available at
+# * http://www.opensource.org/licenses/bsd-license.php
+# *
+# * Contributors:
+# *     IBM Corporation - initial implementation
+# ****************************************************************************/
+
+ifndef TOP
+  TOP = $(shell while ! test -e make.rules; do cd ..  ; done; pwd)
+  export TOP
+endif
+include $(TOP)/make.rules
+
+CFLAGS += -I. -I.. -I../libc/include -I$(SLOFCMNDIR) -I$(INCLCMNDIR)
+
+SRCS =	bootmenu.c
+
+OBJS = $(SRCS:%.c=%.o)
+
+TARGET = ../libbootmenu.a
+
+all: $(TARGET)
+
+$(TARGET): $(OBJS)
+	$(AR) -rc $@ $(OBJS)
+	$(RANLIB) $@
+
+clean:
+	$(RM) $(TARGET) $(OBJS)
+
+distclean: clean
+	$(RM) Makefile.dep
+
+
+# Rules for creating the dependency file:
+depend:
+	$(RM) Makefile.dep
+	$(MAKE) Makefile.dep
+
+Makefile.dep: Makefile
+	$(CC) -M $(CPPFLAGS) $(CFLAGS) $(SRCS) > Makefile.dep
+
+# Include dependency file if available:
+-include Makefile.dep
diff --git a/lib/libbootmenu/bootmenu.c b/lib/libbootmenu/bootmenu.c
new file mode 100644
index 0000000..e5cb4b2
--- /dev/null
+++ b/lib/libbootmenu/bootmenu.c
@@ -0,0 +1,187 @@
+/*****************************************************************************
+ * Boot menu: Displays boot devices and waits for user to select one
+ *
+ * Copyright 2017 Red Hat, Inc.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     Thomas Huth, Red Hat Inc. - initial implementation
+ *****************************************************************************/
+
+#include <stdbool.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <paflof.h>
+#include <helpers.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);
+	if (!path) {
+		puts("Out of memory in find_alias");
+		return NULL;
+	}
+	memcpy(path, (void *)forth_pop(), len);
+	path[len] = '\0';
+
+	return path;
+}
+
+static void bootmenu_populate_devs_alias(const char *alias)
+{
+	int idx;
+
+	for (idx = 0; idx <= 9 && nr_devs < MAX_DEVS; idx++, nr_devs++) {
+		char *cur_alias = bootdevs[nr_devs].alias;
+		if (idx == 0)
+			strcpy(cur_alias, alias);
+		else
+			sprintf(cur_alias, "%s%i", alias, idx);
+		bootdevs[nr_devs].path = find_alias(cur_alias);
+		if (!bootdevs[nr_devs].path)
+			break;
+	}
+}
+
+static void bootmenu_populate_devs(void)
+{
+	bootmenu_populate_devs_alias("cdrom");
+	bootmenu_populate_devs_alias("disk");
+	bootmenu_populate_devs_alias("net");
+}
+
+static void bootmenu_free_devs(void)
+{
+	while (nr_devs-- > 0) {
+		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);
+	}
+}
+
+static bool has_key(void)
+{
+	forth_eval("key?");
+	return forth_pop();
+}
+
+static char get_key(void)
+{
+	forth_eval("key");
+	return forth_pop();
+}
+
+/* Flush pending key presses */
+static void flush_keys(void)
+{
+	uint32_t start;
+
+	start = SLOF_GetTimer();
+	while (SLOF_GetTimer() - start < 10) {
+		if (has_key()) {
+			get_key();
+			start = SLOF_GetTimer();
+		}
+	}
+}
+
+static int bootmenu_get_selection(void)
+{
+	char key = 0;
+	int sel;
+
+	do {
+		sel = -1;
+		if (!has_key())
+			continue;
+		key = get_key();
+		switch (key) {
+		case '0':
+			return -1;
+		case '1' ... '9':
+			sel = key - '1';
+			break;
+		case 'a' ... 'z':
+			sel = key - 'a' + 9;
+			break;
+		case 'A' ... 'Z':
+			sel = key - 'A' + 9;
+			break;
+		default:
+			/* Might be another escape code (F12) ... skip it */
+			flush_keys();
+			break;
+		}
+	} while (sel < 0 || sel >= nr_devs);
+
+	return sel;
+}
+
+void bootmenu(void)
+{
+	int sel;
+
+	bootmenu_populate_devs();
+	if (!nr_devs) {
+		puts("No available boot devices!");
+		return;
+	}
+
+	puts("\nSelect boot device (or press '0' to abort):");
+	bootmenu_show_devs();
+
+	if (has_key())		/* In case the user hammered on F12 */
+		flush_keys();
+
+	sel = bootmenu_get_selection();
+	if (sel < 0) {
+		forth_push(0);
+	} else {
+		forth_push((unsigned long)bootdevs[sel].alias);
+		forth_push(strlen(bootdevs[sel].alias));
+	}
+
+	bootmenu_free_devs();
+}
diff --git a/lib/libbootmenu/bootmenu.code b/lib/libbootmenu/bootmenu.code
new file mode 100644
index 0000000..2a55c09
--- /dev/null
+++ b/lib/libbootmenu/bootmenu.code
@@ -0,0 +1,20 @@
+/*****************************************************************************
+ * Boot menu: Glue code to Forth
+ *
+ * Copyright 2017 Red Hat, Inc.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     Thomas Huth, Red Hat Inc. - initial implementation
+ *****************************************************************************/
+
+#include "bootmenu.h"
+
+// ( -- [str] len|0 )
+PRIM(boot_X2d_menu)
+	bootmenu();
+MIRP
diff --git a/lib/libbootmenu/bootmenu.h b/lib/libbootmenu/bootmenu.h
new file mode 100644
index 0000000..6cef237
--- /dev/null
+++ b/lib/libbootmenu/bootmenu.h
@@ -0,0 +1,15 @@
+/*****************************************************************************
+ * Boot menu definitions
+ *
+ * Copyright 2017 Red Hat, Inc.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     Thomas Huth, Red Hat Inc. - initial implementation
+ *****************************************************************************/
+
+extern void bootmenu(void);
diff --git a/lib/libbootmenu/bootmenu.in b/lib/libbootmenu/bootmenu.in
new file mode 100644
index 0000000..5cb120e
--- /dev/null
+++ b/lib/libbootmenu/bootmenu.in
@@ -0,0 +1,15 @@
+/*****************************************************************************
+ * Boot menu: Definitions for Forth
+ *
+ * Copyright 2017 Red Hat, Inc.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     Thomas Huth, Red Hat Inc. - initial implementation
+ *****************************************************************************/
+
+cod(boot-menu)