Add umpf-flags support to control the EXTRAVERSION patching

[bith3ad]

Add support to specify umpf-flags which influence the umpf build behaviour. The flags are tracked within the umpf tag via the new 'umpf-flags' section. Users can flags directly via the useries or by specfiy them via the command line option '--flags'.

The EXTRAVERSION patch conflicts if a stable update is done without using umpf, e.g. if multiple parties do stable updates for certain software package like Linux but only a few of them use umpf.

To avoid EXTRAVERSION conflicting each time a stable update is done we shift the EXTRAVERSION patching down into the middle of the Makefile by using the new umpf-flags mechanism:

# umpf-flags: extraversion=conflictfree

New flags can be added by extending the SUPPORTED_FLAGS list and adding the flag_ array, e.g.:

SUPPORTED_FLAGS=("extraversion" "foo")

...

flag_foo[val] = "baz"		# default value
flag_foo[values] = "baz bar"	# all possible values

To use the flag, you need to check the value, e.g.:

[ ${flag_foo[val]} == "baz" ] && echo "default value"

[michaelolbrich]

This will fail with umpf continue. You need to store the flags somehow. Maybe similar to OVERRIDES:

• Make FLAGS an associative array and fill it with the defaults (key is the flag name)
• Store all possible values in the associative array FLAG_VALUES (or whatever) with the same keys
• update FLAGS with the custom values
• save FLAGS in bailout() just like OVERRIDES

Btw, ${!FLAGS[*]} would be the list of supported flags.

And take a look at the CI results shellcheck has some errors but that's code the will probably change anyways.

[bith3ad]

Thanks for your input. I fixed the corner case by saving the --flags parameter during bailout like you suggested. On the other hand to ensure that flags will be added to a provided git-umpf-tagI went the way relative did. I also fixed the missing init() and the variable an value assignment issue.

[michaelolbrich]

The state handling is getting quite complex and needs some kind of refactoring, but that's out of scope for this PR.