[patch] more configurable menu generation

[Alex Efros]

Hi!

I've developed a patch which implement few related features:
- ability to define which linux kernels and in which order will be listed
  in top menu instead of single auto-detected latest kernel
- ability to show kernel version in top menu items, to distinguish between
  different kernels added by previous feature
- ability to use custom kernel command line parameters for depending on
  kernel version instead of GRUB_CMDLINE_LINUX_DEFAULT for all kernels


Here is my real use-case explaining needs in these features. I'm
experimenting with switching between proprietary nvidia driver and
nouveau. My main kernel is 3.10.1-hardened-r1 (for proprietary nvidia
driver), and I've also compiled experimental kernel with "_nouveau" local
version: 3.10.1-hardened-r1_nouveau.

First issue - auto-detect of latest kernel choose
3.10.1-hardened-r1_nouveau, which is wrong for me, and only way to change
this is add some fake local version for main kernel just to make sure it
will be sorted before "_nouveau" string.

Second issue - main kernel need "vga=" parameter, while nouveau kernel
need "video=" parameter, but there is no way to configure this.

Third issue - I'd like to have both normal and nouveau kernels in main
menu, in manually defined order.


All these features configured in /etc/default/grub using new variables:
GRUB_SIMPLE_VERSION, GRUB_MENU_LINUX, GRUB_CMDLINE_LINUX_CUSTOM. Example:

---cut---
# Show kernel version in top menu entries
GRUB_SIMPLE_VERSION=true

# Manually define list of top menu entries instead of auto-detecting
# latest kernel.
GRUB_MENU_LINUX='
    /boot/vmlinuz-3.10.1-hardened-r1
    /boot/vmlinuz-3.10.1-hardened-r1_nouveau
'

# Append parameters to the linux kernel command line for non-recovery entries
# for some kernels (instead of GRUB_CMDLINE_LINUX_DEFAULT)
# Should contain any amount of pairs: shell pattern for kernel version and
# kernel command line for it (must be quoted if contain spaces).
# First matched pattern will be used. Example:
# GRUB_CMDLINE_LINUX_CUSTOM='
#       *_nouveau               video=800x600
#       3.10.*                  "vga=0x315 it87.force_id=0x8721"
#       3.9.9-hardened          "init=/bin/sh"
# '
GRUB_CMDLINE_LINUX_CUSTOM='
        *_nouveau               "video=800x600"
'
---cut---


Attached patch is for grub-2.00_p5107. Patch tested with dash and bash.

-- 
                        WBR, Alex.

customize_menu.patch
Description: Source code patch