30_os-prober fails in make_timeout() when using GRUB_BUTTON_CMOS_ADDRESS

[TJ]

I've been configuring the alternate OS boot functionality and discovered that "30_os-prober" causes a syntax error in the generated "grub.cfg.new" when GRUB_BUTTON_CMOS_ADDRESS is defined. The bad generated code is:

if cmostest 85:3; then
else
fi

It is obviously missing any statements inside the conditional blocks.

The cause is make_timeout() only generating output when "$found_other_os" is empty. In the case of using GRUB_BUTTON_CMOS_ADDRESS its entire purpose is to use the alternative OS boot button that some PCs have.

I'll do a merge request later but the quick-fix to "/etc/grub/30_os-prober" is:

make_timeout() {
  if [ "x${found_other_os}" = "x" -o "x${GRUB_BUTTON_CMOS_ADDRESS}" != "x" ]; then

[Colin Watson (cjwatson)]

Could you try 2.02~beta2-*, now in trusty? The timeout code looks rather different there, and shouldn't suffer from this.

[TJ (tj)]

Looks to be solved. The generated grub script:

if cmostest 85:3 ; then
   set default="0"
elif [ "${next_entry}" ] ; then
   set default="${next_entry}"
   set next_entry=
   save_env next_entry
   set boot_once=true
else
   set default="0"
fi