add chroot helper for virt-rescue, Bug 674684 - mount-rootfs-and-do-chroot.sh

OBS-URL: https://build.opensuse.org/package/show/Virtualization/libguestfs?expand=0&rev=84

libguestfs.mkinitrd.setup.sh

@@ -32,3 +32,53 @@ do
 		fi
 	done
 done
+
+# Bug 674684 - mount-rootfs-and-do-chroot.sh
+cat > $tmp_mnt/bin/mount-rootfs-and-do-chroot.sh <<'__EOF__'
+#!/bin/bash
+# Usage: $0 /dev/sda5
+rootfs=$1
+mnt=/sysroot
+mounts=
+
+if test -b "${rootfs}"
+then
+
+	mkdir -v -p "${mnt}"
+
+	if mount -v "${rootfs}" "${mnt}"
+	then
+
+		for i in dev proc sys selinux
+		do
+			if test -d /${i} && test -d "${mnt}/${i}"
+			then
+				mount -v --bind /${i} "${mnt}/${i}"
+			fi
+		done
+
+		chroot "${mnt}" su -
+
+		while read b m rest
+		do
+			case "${m}" in
+				${mnt}*)
+					mounts="${m} ${mounts}"
+				;;
+			esac
+		done <<-EOF
+`
+cat < /proc/mounts
+`
+EOF
+
+		for i in ${mounts}
+		do
+			umount -v "${i}"
+		done
+
+	fi
+
+fi
+__EOF__
+