Help with versioning scheme

[Martin Waschbüsch]

Thanks, Freddie,
> Am 17.01.2018 um 19:35 schrieb Freddie Cash <fjwcash at gmail.com>:
> 
> On Wed, Jan 17, 2018 at 10:29 AM, Martin Waschbüsch <martin at waschbuesch.de <mailto:martin at waschbuesch.de>> wrote:
> Hi Adam,
> > Am 17.01.2018 um 19:19 schrieb Adam Weinberger <adamw at adamw.org <mailto:adamw at adamw.org>>:
> > Hi Martin,
> >
> > You don't want to use the upstream version to represent PORTREVISION. PORTREVISION is for when you need to force rebuilds of the port itself, and so tying it to upstream would make it impossible to bump it ourselves.
> >
> > Why do you need to ignore the fourth digit? It's perfectly valid for our purposes.
> 
> So far, I had (because it coincided with their version number) used it to provide SO_VER. But that breaks now:
> 
> ---
> # Created by: adamw
> # $FreeBSD: head/archivers/liblz4/Makefile 448415 2017-08-20 12:30:25Z sunpoet $
> 
> PORTNAME=       lz4
> PORTVERSION=    1.8.1
> DISTVERSIONPREFIX=      v
> PORTEPOCH=      1
> CATEGORIES=     archivers
> PKGNAMEPREFIX=  lib
> 
> MAINTAINER=     martin at waschbuesch.de <mailto:martin at waschbuesch.de>
> COMMENT=        LZ4 compression library, lossless and very fast
> 
> LICENSE=        BSD2CLAUSE GPLv2
> LICENSE_COMB=   multi
> 
> USES=           gmake pathfix pkgconfig
> USE_GITHUB=     yes
> USE_LDCONFIG=   yes
> #PATHFIX_MAKEFILEIN=    Makefile
> 
> ALL_TARGET=     default         # don't remove this
> SO_VER=         ${PORTVERSION}
> PLIST_SUB+=     SO_VER=${SO_VER} SO_VER_MAJ=${SO_VER:R:R}
> 
> ​Why can't you do something like the above to get SO_VER?
> 
> PORTVERSION=1.8.1.2
> SO_VER=${PORTVERSION:R:R:R)
> 
> Similar to how you get SO_VER_MAJ out of SO_VER.​

That is true. Do you think this is a robust solution, though?
Or is the whole relying on upstream variables idea problematic?