[arch-general] How to "decorate" a package build?

[Ralf Mardorf]

On Wed, 8 Mar 2017 11:45:37 +0100, Peter Nabbefeld wrote:
>is it possible to decorate a package build, i.e. set some prconditions 
>(like exporting variables) and probably even change the build process 
>(compile instead of copying just the binaries)?
>
>E.g., to modify the firefox package update to first compile with 
>"--enable-alsa". Of course, I would have to create my own package in a 
>private repository. The new PKGBUILD file would need to refer the 
>original one, to get e.g. the package version number. However, the 
>private package would always have the same version, so the official 
>package change needs to be hooked to the generic private package:
>
>Official Package Changed --«Signal»--> Private Package Update
>--«Inherits»--> Official Package Update

This isn't worth the effort, however...

1. disable updating the firefox package:

/etc/pacman.conf
IgnorePkg   = firefox

2. write a wrapper for pacman that first compares the installed
   version, with the version provided by the repositories

pacman -Q firefox | cut -d\  -f2
pacman -Si firefox | grep Version | cut -d: -f2

3. use the sed command, so that the wrapper could edit the version
   mentioned by your PKGBUILD

4. let the wrapper build and install your package

5. let the wrapper run a regular "pacman" with $@ options

IMO it's easier to use apulse-git and if you should use freedesktop.org
menus, to edit a desktop file to launch "apulse firefox" by a sript.

Regards,
Ralf