Re: multi-variant packages and bulk builds

[Aleksey Cheusov <cheusov%tut.by@localhost>]

> In pkgsrc there are a number of packages (category/package) that can
> be built with different PKGNAME depending on a value of some special
> variables. For example, www/ap2-* packages, */py-* and many others.

Patch in the attached file implements a proposed idea.
It is very small and simple.

For remind: idea is to develop a pkgsrc API for multi-variant packages
(py23-xxx, py24-xxx, py25-xxx etc.). Using this API bulk build
programs can generate appropriate binaries easily and without
hardcodes.

How it works (tested)

  0 ~>cd /srv/pkgsrc/wip/dict-server/
  0 dict-server>bmake show-var VARNAME=VARIANTS

  0 dict-server>cd ../../www/ap-php
  0 ap-php>bmake show-var VARNAME=VARIANTS
  PHP_VERSION_DEFAULT=4,5 PKG_APACHE_DEFAULT=apache13,apache2,apache22
  0 ap-php>cd ../../www/ap2-python
  0 ap2-python>bmake show-var VARNAME=VARIANTS
  PYTHON_VERSION_DEFAULT=25,24,23 PKG_APACHE_DEFAULT=apache2,apache22
  0 ap2-python>cd ../../www/ap-python
  0 ap-python>bmake show-var VARNAME=VARIANTS
  PYTHON_VERSION_DEFAULT=23,21
  0 ap-python>cd ../../www/ap2-chroot
  0 ap2-chroot>bmake show-var VARNAME=VARIANTS
  PKG_APACHE_DEFAULT=apache2,apache22
  0 ap2-chroot>cd ../../net/php-sockets
  0 php-sockets>bmake show-var VARNAME=VARIANTS
  PHP_VERSION_DEFAULT=4,5
  0 php-sockets>

-- 
Best regards, Aleksey Cheusov.