ports/188693: [OPTIONS_SINGLE]: bug allows user to choose two single options simultaneously

[Renato Botelho]

>Number:         188693
>Category:       ports
>Synopsis:       [OPTIONS_SINGLE]: bug allows user to choose two single options simultaneously
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-ports-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Apr 16 14:00:00 UTC 2014
>Closed-Date:
>Last-Modified:
>Originator:     Renato Botelho
>Release:        10-STABLE
>Organization:
ESF LLC
>Environment:
FreeBSD pfbuilder22 10.0-STABLE FreeBSD 10.0-STABLE #0 1cbbe6f(stable/10): Tue Apr 15 10:21:56 BRT 2014     root at pfbuilder22:/usr/obj/usr/pfSensesrc/src/sys/GENERIC  amd64
>Description:
When you define a OPTIONS_SINGLE, it's not supposed to let user choose 2 of the available options, but it can happen using WITH on command line
>How-To-Repeat:
# cd /usr/ports/emulators/fuse
# make rmconfig

# make showconfig
===> The following configuration options are available for fuse-1.1.1_2:
     AO=off: libao audio library support
     ICONS=on: Install icon theme(s)
     ROMS=off: Extra ROM images (128p, 256s, Gluck, IF1, Opus, TrDOS)
====> User Interface: you have to select exactly one of them
     GTK2=on: GTK+ 2 GUI toolkit support
     GTK3=off: GTK+ 3 GUI toolkit support
     SDL=off: Simple Direct Media Layer support
     SVGALIB=off: SVGA graphics support
===> Use 'make config' to modify these settings

# make WITH=SDL showconfig
===> The following configuration options are available for fuse-1.1.1_2:
     AO=off: libao audio library support
     ICONS=on: Install icon theme(s)
     ROMS=off: Extra ROM images (128p, 256s, Gluck, IF1, Opus, TrDOS)
====> User Interface: you have to select exactly one of them
     GTK2=on: GTK+ 2 GUI toolkit support
     GTK3=off: GTK+ 3 GUI toolkit support
     SDL=on: Simple Direct Media Layer support
     SVGALIB=off: SVGA graphics support
===> Use 'make config' to modify these settings

In this case, GTK2 should be marked as 'off', but it's not and user ends with 
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: