add sysupgrade script for config preserving system upgrades. only implemented for x86-2.6 at the moment, but can be ported to other platforms easily

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@8456 3c298f89-4303-0410-b956-a3cf2f4a3e73

package/base-files/files/etc/preinit

@@ -60,6 +60,14 @@ echo "$HOTPLUG" > /proc/sys/kernel/hotplug
 eval ${FAILSAFE:+failsafe}
 lock -w /tmp/.failsafe
 mount_root
+[ -f /sysupgrade.tgz ] && {
+	echo "- config restore -"
+	cd /
+	mv sysupgrade.tgz /tmp
+	tar xzf /tmp/sysupgrade.tgz
+	rm -f /tmp/sysupgrade.tgz
+	sync
+}
 
 echo "- init -"
 	

package/base-files/files/lib/upgrade/common.sh

@@ -0,0 +1,151 @@
+#!/bin/sh
+
+RAM_ROOT=/tmp/root
+
+ldd() { LD_TRACE_LOADED_OBJECTS=1 $*; }
+libs() { ldd $* | awk '{print $3}'; }
+
+install_file() { # <file> [ <file> ... ]
+	for file in "$@"; do
+		dest="$RAM_ROOT/$file"
+		[ -f $file -a ! -f $dest ] && {
+			dir="$(dirname $dest)"
+			mkdir -p "$dir"
+			cp $file $dest
+		}
+	done
+}
+
+install_bin() { # <file> [ <symlink> ... ]
+	src=$1
+	files=$1
+	[ -x "$src" ] && files="$src $(libs $src)"
+	install_file $files
+	shift
+	for link in "$@"; do {
+		dest="$RAM_ROOT/$link"
+		dir="$(dirname $dest)"
+		mkdir -p "$dir"
+		[ -f "$dest" ] || ln -s $src $dest
+	}; done
+}
+
+pivot() { # <new_root> <old_root>
+	mount | grep "on $1 type" 2>&- 1>&- || mount -o bind $1 $1
+	mkdir -p $1$2 $1/proc $1/dev $1/tmp $1/jffs && \
+	mount -o move /proc $1/proc && \
+	pivot_root $1 $1$2 || {
+        umount $1 $1
+		return 1
+	}
+	mount -o move $2/dev /dev
+	mount -o move $2/tmp /tmp
+	mount -o move $2/jffs /jffs 2>&-
+	return 0
+}
+
+run_ramfs() { # <command> [...]
+	install_bin /bin/busybox /bin/ash /bin/sh /bin/mount /bin/umount /sbin/pivot_root /usr/bin/wget /sbin/reboot /bin/sync /bin/dd /bin/grep /bin/cp /bin/mv /bin/tar /usr/bin/md5sum "/usr/bin/[" /bin/vi
+	install_bin /sbin/mtd
+	for file in $RAMFS_COPY_BIN; do
+		install_bin $file
+	done
+	install_file /etc/resolv.conf /etc/functions.sh /lib/upgrade/*.sh $RAMFS_COPY_DATA
+
+	pivot $RAM_ROOT /mnt || {
+		echo "Failed to switch over to ramfs. Please reboot."
+		exit 1
+	}
+
+	mount -o remount,ro /mnt
+	umount -l /mnt
+
+	grep /jffs /proc/mounts > /dev/null && {
+		mount -o remount,ro /jffs
+		umount -l /jffs
+	}
+
+	# spawn a new shell from ramdisk to reduce the probability of cache issues
+	exec /bin/busybox ash -c "$*"
+}
+
+run_hooks() {
+	local arg="$1"; shift
+	for func in "$@"; do
+		eval "$func $arg"
+	done
+}
+
+ask_bool() {
+	local default="$1"; shift;
+	local answer="$default"
+
+	[ "$INTERACTIVE" -eq 1 ] && {
+		case "$default" in
+			0) echo -n "$* (y/N): ";;
+			*) echo -n "$* (Y/n): ";;
+		esac
+		read answer
+		case "$answer" in
+			y*) answer=1;;
+			n*) answer=0;;
+			*) answer="$default";;
+		esac
+	}
+	[ "$answer" -gt 0 ]
+}
+
+v() {
+	[ "$VERBOSE" -ge 1 ] && echo "$@"
+}
+
+rootfs_type() {
+	mount | awk '($3 ~ /^\/$/) && ($5 !~ /rootfs/) { print $5 }'
+}
+
+get_image() {
+	local from="$1"
+
+	case "$from" in
+		http://*|ftp://*) wget -O- -q "$from";;
+		*) cat "$from"
+	esac
+}
+
+get_magic_word() {
+	get_image "$1" | dd bs=2 count=1 2>/dev/null | hexdump | awk '$2 { print $2 }'
+}
+
+refresh_mtd_partitions() {
+	mtd refresh rootfs
+}
+
+jffs2_copy_config() {
+	if grep rootfs_data /proc/mtd >/dev/null; then
+		# squashfs+jffs2
+		mtd -e rootfs_data jffs2write "$CONF_TAR" rootfs_data
+	else
+		# jffs2
+		mtd jffs2write "$CONF_TAR" rootfs
+	fi
+}
+
+do_upgrade() {
+	v "Performing system upgrade..."
+	platform_do_upgrade "$ARGV"
+	
+	[ "$SAVE_CONFIG" -eq 1 ] && {
+		v "Refreshing partitions"
+		if type 'platform_refresh_partitions' >/dev/null 2>/dev/null; then
+			platform_refresh_partitions
+		else
+			refresh_mtd_partitions
+		fi
+		if type 'platform_copy_config' >/dev/null 2>/dev/null; then
+			platform_copy_config
+		else
+			jffs2_copy_config
+		fi
+	}
+	ask_bool 1 "Reboot" && reboot
+}

package/base-files/files/sbin/sysupgrade

@@ -0,0 +1,92 @@
+#!/bin/sh
+. /etc/functions.sh
+
+# initialize defaults
+RAMFS_COPY_BIN=""	# extra programs for temporary ramfs root
+RAMFS_COPY_DATA=""	# extra data files
+export INTERACTIVE=0
+export VERBOSE=1
+export SAVE_CONFIG=1
+
+# parse options
+while [ -n "$1" ]; do 
+	case "$1" in
+		-i) export INTERACTIVE=1;;
+		-v) export VERBOSE="$(($VERBOSE + 1))";;
+		-q) export VERBOSE="$(($VERBOSE - 1))";;
+		-*)
+			echo "Invalid option: $1"
+			exit 1
+		;;
+		*) break;;
+	esac
+	shift;
+done
+
+export CONFFILES=/tmp/sysupgrade.conffiles
+export CONF_TAR=/tmp/sysupgrade.tgz
+
+export ARGV="$*"
+export ARGC="$#"
+
+[ -z "$ARGV" ] && {
+	cat <<EOF
+Usage: $0 [options] <image file or URL>
+
+Options:
+	-i	interactive mode
+	-v	more verbose
+	-q	less verbose
+
+EOF
+	exit 1
+}
+
+add_uci_conffiles() {
+	local file="$1"
+	find /etc/config > "$file"
+	return 0
+}
+
+# hooks
+sysupgrade_image_check="platform_check_image"
+sysupgrade_init_conffiles="add_uci_conffiles"
+
+include /lib/upgrade
+
+do_save_conffiles() {
+	[ -z "$(rootfs_type)" ] && {
+		echo "Cannot save config while running from ramdisk."
+		ask_bool 0 "Abort" && exit
+		return 0
+	}
+	run_hooks "$CONFFILES" $sysupgrade_init_conffiles
+	ask_bool 0 "Edit config file list" && vi "$CONFFILES"
+
+	v "Saving config files..."
+	[ "$VERBOSE" -gt 1 ] && TAR_V="v" || TAR_V=""
+	tar c${TAR_V}zf "$CONF_TAR" -T "$CONFFILES" 2>/dev/null
+}
+
+type platform_check_image >/dev/null 2>/dev/null || {
+	echo "Firmware upgrade is not implemented for this platform."
+	exit 1
+}
+
+for check in $sysupgrade_image_check; do
+	( eval "$check \"\$ARGV\"" ) || {
+		echo "Image check '$check' failed."
+		exit 1
+	}
+done
+
+if ask_bool $SAVE_CONFIG "Keep config files over reflash"; then
+	do_save_conffiles
+	export SAVE_CONFIG=1
+else
+	export SAVE_CONFIG=0
+fi
+run_hooks "" $sysupgrade_pre_upgrade
+
+v "Switching to ramdisk..."
+run_ramfs '. /etc/functions.sh; include /lib/upgrade; do_upgrade'

package/mtd/src/jffs2.c

@@ -147,7 +147,7 @@ static void add_file(char *name, int parent)
 	else
 		fname = name;
 
-	inode = add_dirent(name, IFTODT(S_IFREG), parent);
+	inode = add_dirent(fname, IFTODT(S_IFREG), parent);
 	memset(&ri, 0, sizeof(ri));
 	ri.magic = JFFS2_MAGIC_BITMASK;
 	ri.nodetype = JFFS2_NODETYPE_INODE;
@@ -223,6 +223,9 @@ int mtd_write_jffs2(char *mtd, char *filename, char *dir)
 		goto done;
 	}
 
+	if (!*dir)
+		target_ino = 1;
+
 	/* parse the structure of the jffs2 first
 	 * locate the directory that the file is going to be placed in */
 	for(;;) {
@@ -253,7 +256,7 @@ int mtd_write_jffs2(char *mtd, char *filename, char *dir)
 					struct jffs2_raw_dirent *de = (struct jffs2_raw_dirent *) node;
 					
 					/* is this the right directory name and is it a subdirectory of / */
-					if ((de->pino == 1) && !strncmp(de->name, dir, de->nsize))
+					if (*dir && (de->pino == 1) && !strncmp(de->name, dir, de->nsize))
 						target_ino = de->ino;
 
 					/* store the last inode and version numbers for adding extra files */

package/mtd/src/mtd.c

@@ -52,7 +52,7 @@
 
 #define DEBUG
 
-#define JFFS2_DEFAULT_DIR	"tmp"
+#define JFFS2_DEFAULT_DIR	"" /* directory name without /, empty means root dir */
 
 #define SYSTYPE_UNKNOWN     0
 #define SYSTYPE_BROADCOM    1

target/linux/x86-2.6/base-files/default/lib/upgrade/platform.sh

@@ -0,0 +1,27 @@
+platform_check_image() {
+	[ "$ARGC" -gt 1 ] && return 1
+
+	case "$(get_magic_word "$1")" in
+		48eb) return 0;;
+		*)
+			echo "Invalid image type"
+			return 1
+		;;
+	esac
+}
+
+platform_do_upgrade() {
+	get_image "$1" > /dev/hda
+	sync
+}
+
+x86_prepare_ext2() {
+	# if we're running from ext2, we need to make sure that we have a mtd 
+	# partition that points to the active rootfs partition.
+	# however this only matters if we actually need to preserve the config files
+	[ "$SAVE_CONFIG" -eq 1 ] && return 0
+	grep rootfs /proc/mtd >/dev/null || {
+		echo /dev/hda2,65536,rootfs > /sys/module/block2mtd/parameters/block2mtd
+	}
+}
+append sysupgrade_pre_upgrade x86_prepare_ext2