pkg/50275: Bootstrapping shlock fails if cwrappers and locking are enabled

[david.sainty%gmail.com@localhost]

>Number:         50275
>Category:       pkg
>Synopsis:       Bootstrapping shlock fails if cwrappers and locking are enabled
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Sep 24 06:35:00 +0000 2015
>Originator:     David Sainty
>Release:        Pkgsrc current
>Organization:
>Environment:
Linux laptop 3.0.0-31-generic-pae #49-Ubuntu SMP Tue Feb 19 20:24:31 UTC 2013 i686 i686 i386 GNU/Linux

>Description:
If you happen to set USE_CWRAPPERS=yes and PKGSRC_LOCKTYPE=sleep in mk.conf on a blank slate Pkgsrc on a system with no native shlock (E.g. Linux), trouble ensues.

Any attempt to install will ask you to install shlock.  But shlock wants cwrappers.  But cwrappers needs shlock.

>How-To-Repeat:
Add to mk.conf:

USE_CWRAPPERS=yes
PKGSRC_LOCKTYPE=sleep

% pkg_delete shlock
% pkg_delete cwrappers
% cd pkgtools/cwrappers
% make install
ERROR: [locking.mk] shlock is not installed.
ERROR: [locking.mk] Please "(cd ../../pkgtools/shlock && /pkg/pkgrootR1/bin/bmake install)".
*** Error code 1

% cd ../shlock
% make install
===> Installing dependencies for shlock-20080529
=> Build dependency cwrappers>=20150314: NOT found
=> Verifying reinstall for ../../pkgtools/cwrappers
ERROR: [locking.mk] shlock is not installed.
ERROR: [locking.mk] Please "(cd ../../pkgtools/shlock && /pkg/pkgrootR1/bin/bmake install)".
*** Error code 1

>Fix:
This could be fixed either by adding PKGSRC_LOCKTYPE=none to cwrappers (like shlock does, but it risks race problems), or something like USE_CWRAPPERS=no to shlock (could be ok...).

This might be a little too niche to address in the freeze.  Anyone getting into this trouble probably knows how to get out :)