main/syslinux: misc update-extlinux fixes

- rename /etc/extlinux-conf to /etc/update-extlinux.conf

- Do not exit with fail if update-extlinux.conf is missing
- Always warn if root= is not defined in update-extlinux.conf
- Try harder to detect the root device by parsing /proc/mounts
- Exit with error if we cannot detect the Root device
- Rename fancy_menu to vesa_menu
- Unifiy the code generating vesa/standard menus
- Keep a backup of old extlinux.conf
- add "overwrite" config option so it is possible to skip overwriting
  the extlinux.conf.

- Added a post-upgrade that imports current extlinux.conf to
  update-extlinux.conf

1 files changed, 82 insertions, 36 deletions

diff --git a/main/syslinux/update-extlinux b/main/syslinux/update-extlinux
index 25585334be..a2488cc8df 100755
--- a/main/syslinux/update-extlinux
+++ b/main/syslinux/update-extlinux
@@ -4,8 +4,13 @@ default=0
 timeout=5
 verbose=0
 
+conf=/boot/extlinux.conf
+myconf=/etc/update-extlinux.conf
+
 # read in extlinux settings
-source /etc/extlinux.conf
+if [ -f "$myconf" ]; then
+	. $myconf
+fi
 
 everbose() {
 	if [ "$verbose" = "0" ]; then
@@ -15,14 +20,44 @@ everbose() {
 	echo $*
 }
 
+ewarn() {
+	echo "WARNING:" $@ >&2
+}
+
+eerror() {
+	echo "ERROR:" $@ >&2
+	return 1
+}
+
 everbose "Updating extlinux configuration."
 
 if [ "x$root" = "x" ]; then
-	everbose "WARNING: Root device not specified, determining automatically."
-	everbose -n "Root device is: "
-	export `blkid -o export /dev/root`
-	root=UUID=$UUID
-	everbose $root
+	ewarn "Root device is not specified in $myconf."
+	blkid_export=$(blkid -o export /dev/root)
+	if [ -n "$blkid_export" ]; then
+		export $blkid_export
+	fi
+	if [ -z "$UUID" ]; then
+		# try parse /proc/mount for mounted /
+		dev=$(awk '$2 == "/" {dev=$1} END {print dev}' /proc/mounts)
+		if [ -n "$dev" ]; then
+			blkid_export=$(blkid -o export $dev)
+			if [ -n "$blkid_export" ]; then
+				export "$blkid_export"
+			fi
+		fi
+	fi
+	if [ -z "$UUID" ]; then
+		if [ -z "$dev" ]; then
+			eerror "Failed to detect root device"
+			exit 1
+		else
+			root=$dev
+		fi
+	else
+		root=UUID=$UUID
+	fi
+	everbose "Root device is: $root"
 fi
 
 everbose "Installing mboot.c32 to /boot."
@@ -32,29 +67,26 @@ everbose "Installing menu.c32 to /boot."
 cp /usr/share/syslinux/menu.c32 /boot
 
 rtimeout=$((${timeout}\*10))
+syslinux_menu=menu.c32
+menu_hidden=
+
 # vesa menu has been requested?
-if [ "$fancy_menu" = "1" ]; then
-	everbose "Installing vesamenu.c32 to /boot."
-	cp /usr/share/syslinux/vesamenu.c32 /boot
-
-	echo "DEFAULT vesamenu.c32" > /boot/extlinux.conf.new
-	echo "PROMPT 0" >> /boot/extlinux.conf.new
-	echo "MENU TITLE Alpine/$(uname -s) Boot Menu" >> /boot/extlinux.conf.new
-	if [ "$hidden" = "1" ]; then
-		echo "MENU HIDDEN" >> /boot/extlinux.conf.new
-	fi
-	echo "MENU AUTOBOOT Alpine will be booted automatically in # seconds." >> /boot/extlinux.conf.new
-	echo "TIMEOUT $rtimeout" >> /boot/extlinux.conf.new
-else
-	echo "DEFAULT menu.c32" > /boot/extlinux.conf.new
-	echo "PROMPT 0" >> /boot/extlinux.conf.new
-	echo "MENU TITLE Alpine/$(uname -s) Boot Menu" >> /boot/extlinux.conf.new
-	if [ "$hidden" = "1" ]; then
-		echo "MENU HIDDEN" >> /boot/extlinux.conf.new
-	fi
-	echo "MENU AUTOBOOT Alpine will be booted automatically in # seconds." >> /boot/extlinux.conf.new
-	echo "TIMEOUT $rtimeout" >> /boot/extlinux.conf.new
+if [ "$vesa_menu" = "1" ]; then
+	syslinux_menu=vesamenu.c32
+fi
+
+everbose "Installing $syslinux_menu to /boot."
+cp /usr/share/syslinux/vesamenu.c32 /boot
+
+echo "# Generated by update-extlinux" > $conf.new
+echo "DEFAULT $syslinux_menu" >> $conf.new
+echo "PROMPT 0" >> $conf.new
+echo "MENU TITLE Alpine/$(uname -s) Boot Menu" >> $conf.new
+if [ "$hidden" = "1" ]; then
+	echo "MENU HIDDEN" >> $conf.new
 fi
+echo "MENU AUTOBOOT Alpine will be booted automatically in # seconds." >> $conf.new
+echo "TIMEOUT $rtimeout" >> $conf.new
 
 lst=0
 for kernel in $(find /boot -name vmlinuz-* -type f); do
@@ -66,24 +98,38 @@ for kernel in $(find /boot -name vmlinuz-* -type f); do
 		initramfs="initrd=initramfs-$tag"
 	fi
 
-	echo "LABEL $lst" >> /boot/extlinux.conf.new
+	echo "LABEL $lst" >> $conf.new
 	if [ "$lst" = "$default" ]; then
-		echo "  MENU DEFAULT" >> /boot/extlinux.conf.new
+		echo "  MENU DEFAULT" >> $conf.new
 	fi
-	echo "  MENU LABEL Linux $tag" >> /boot/extlinux.conf.new
-	echo "  KERNEL $(basename $kernel)" >> /boot/extlinux.conf.new
-	echo "  APPEND $initramfs root=$root modules=$modules,$TYPE $default_kernel_opts" >> /boot/extlinux.conf.new
+	echo "  MENU LABEL Linux $tag" >> $conf.new
+	echo "  KERNEL $(basename $kernel)" >> $conf.new
+	echo "  APPEND $initramfs root=$root modules=${modules}${TYPE:+,$TYPE} $default_kernel_opts" >> $conf.new
+	echo "" >> $conf.new
 	lst=$(($lst + 1))
 done
 
 if [ -f "/boot/memtest" ]; then
 	everbose "Found memtest86+: /boot/memtest"
-	echo "LABEL $lst" >> /boot/extlinux.conf.new
-	echo "  MENU LABEL Memtest86+" >> /boot/extlinux.conf.new
-        echo "  KERNEL memtest" >> /boot/extlinux.conf.new
+	echo "LABEL $lst" >> $conf.new
+	echo "  MENU LABEL Memtest86+" >> $conf.new
+        echo "  KERNEL memtest" >> $conf.new
+	echo "" >> $conf.new
         lst=$(($lst + 1))
 fi
 
 everbose "$lst entries found."
 
-mv /boot/extlinux.conf.new /boot/extlinux.conf
+for entry in /etc/update-extlinux.d/*; do
+	[ -f "$entry" ] && cat $entry >> $conf.new
+done	
+
+if [ "$overwrite" = "1" ]; then
+	# keep a backup just in case
+	if [ -f "$conf" ]; then
+		mv $conf $conf.old
+	fi
+
+	mv $conf.new $conf
+fi
+