run: use GPT for image/disk BIOS legacy

Issue #2778

The "create_grub2" script functionality is moved to the g2fg contrib sources
and also the GRUB2 head image (tool/grub2-head.img). The head image is now
partitioned as GPT and bootable in BIOS legacy mode.

tool/run/image/disk

@@ -4,7 +4,7 @@
 # \param --image-disk-size   disk size in MiB
 #
 
-source [genode_dir]/tool/run/iso.inc
+source [genode_dir]/tool/run/grub2.inc
 
 
 proc image_disk_size { } { return [get_cmd_arg --image-disk-size 0] }
@@ -16,34 +16,64 @@ proc image_disk_size { } { return [get_cmd_arg --image-disk-size 0] }
 proc run_image { {unused ""} } {
 
 	requires_installation_of parted
-	requires_installation_of resize2fs
-	requires_installation_of fallocate
+	requires_installation_of e2cp
+
+	# make copy of template grub2 header image
+	exec cp [get_grub2_dir]/boot/grub2-head.img [run_dir].header
+
+	# remove template partition
+	exec parted -a none -s [run_dir].header -- rm 3
+
+	# calculate size of grub2 header and the size of Genode scenario
+	set size_header [expr [regsub {\s.*} [exec du -b  [run_dir].header] {}]]
+	set size_run    [expr [regsub {\s.*} [exec du -skL [run_dir]] {}]]
 
-	set grub_img   "[genode_dir]/tool/grub2-head.img"
-	set disk_img   "[run_dir].img"
-	set part1_img  "[run_dir]-part1.img"
-	set run_size   [expr [regsub {\s.*} [exec du -sm [run_dir]] {}] + 8]
 	if {[image_disk_size] > 0} {
-		set disk_size  [image_disk_size]
+		set disk_size_kb [expr [image_disk_size] * 1024 * 1024]
 	} else {
-		set disk_size $run_size
+		set disk_size_kb [expr ($size_run + 256) / 32 * 32]
 	}
-	set part1_size [expr $disk_size - 1]MiB
 
-	# extract and resize partition image
-	exec dd if=$grub_img of=$part1_img bs=1M skip=1  2>/dev/null
-	exec fallocate -l $part1_size $part1_img
-	exec resize2fs $part1_img  2>/dev/null
+	# setup partition with content
+	exec dd if=/dev/zero of=[run_dir].partition bs=1k count=$disk_size_kb 2>/dev/null
+	exec mkfs.ext2 -L GENODE* -q -T default [run_dir].partition
 
-	# populate partition with binaries
-	exec [genode_dir]/tool/rump -F ext2fs -p [run_dir] $part1_img
+	# copy content to disk image
+	foreach file [exec find [run_dir]] {
+		set filename [string replace $file 0 [string length [run_dir]] ""]
+		if {[string length $filename] == 0} {
+			continue
+		}
+
+		if {[file isdirectory $file]} {
+			exec e2mkdir [run_dir].partition:$filename
+		} else {
+			exec e2cp $file [run_dir].partition:$filename
+		}
+	}
+
+	# calculate start/end sector of content partition
+	set first_sector [expr $size_header / 512]
+	set last_sector [expr ((($size_header + ($disk_size_kb * 1024)) / 512) - 1)]
+
+	# add free space for the backup gpt at the end of disk
+	set sector_backup [exec parted -s [run_dir].header 'unit s print']
+	set sector_backup [regexp -all -inline { 1 .*BIOSBOOT} $sector_backup]
+	set sector_backup [regexp -all -inline {([0-9]+)} $sector_backup]
+	set sector_backup [lindex $sector_backup 2]
+
+	exec dd if=/dev/zero of=[run_dir].empty bs=512 count=$sector_backup 2>/dev/null
 
 	# merge final image from GRUB2 head and partition
-	exec dd if=$grub_img  of=$disk_img status=noxfer bs=1M count=1  2>/dev/null
-	exec dd if=$part1_img of=$disk_img status=noxfer bs=1M seek=1   2>/dev/null
-	exec parted -s $disk_img -- rm 1 mkpart primary 2048s -1s set 1 boot on
+	exec cat [run_dir].header [run_dir].partition [run_dir].empty > [run_dir].img
 
-	exec rm -f $part1_img
+	# cleanup
+	exec rm [run_dir].empty
+	exec rm [run_dir].header
+	exec rm [run_dir].partition
 
-	puts "Created image file $disk_img ($disk_size MiB)"
+	# create partition table entry pointing to the content
+	catch { exec parted -a none [run_dir].img -- mkpart Fix GENODE* ext2 [expr $first_sector]s ${last_sector}s }
+	set size_image [expr [regsub {\s.*} [exec du -sk [run_dir].img] {}]]
+	puts "Created image file [run_dir].img (${size_image}kiB)"
 }