#!/bin/bash
#
# gl-select: select active gl/glx libraries/extensions
#
# Matt Housh, jaeger at morpheus dot net
# Jose V Beneyto, joberui at ei dot upv dot es
#
# For changelog, see:
# http://crux.nu/gitweb/?p=ports/opt.git;a=history;f=gl-select/Pkgfile;hb=2.3
#

infoUsage() {
	echo "Usage: $0 [xorg|nvidia|ati]"
}

infoMissing() {
	echo "One or more of the non-xorg gl/glx backup files are missing. This means"
	echo "either you're not using a non-xorg gl/glx setup, in which case nothing"
	echo "needs to be changed, OR your xorg backups are missing, which can be"
	echo "solved by reinstalling the xorg packages from the CRUX CD or ports."
}

infoRevert() {
	echo "You appear to already be using a non-xorg gl/glx setup. If the"
	echo "one selected isn't the correct one, revert to xorg and then select"
	echo "the correct new setup using 'gl-select xorg; gl-select <new gl/glx>'."
}

# checkInstalled() checks either a single port or list of ports, like so:
#   checkInstalled xorg
#   checkInstalled nvidia nvidia-legacy-96xx nvidia-legacy-71xx
checkInstalled() {
	local notInstalled=1
	for arg in $@
	do
		if [ ! -z "`pkginfo -i | awk '{ print $1 }' | grep -e ^$arg$`" ]
		then
			notInstalled=0
		fi
	done
	if [ $notInstalled -eq 1 ]
	then
		if [ $# -eq 1 ]
		then
			echo "$arg isn't installed!"
		else
			echo "None of the following ports are installed! (one is required)"
			for i in $@
			do
				echo "  $i"
			done
		fi
		exit 1
	fi
}

# if other than a single argument is passed, spit out some help
if [ $# -ne 1 ]
then
	infoUsage
	exit 1
fi

# check for the xorg port; if it's not installed, why is this script even run?
# xorg is a metaport and it's possible that the proper deps might not all be
# installed; more strict error checking may be implemented at a later date
checkInstalled xorg

# perform the selection for the following supported gl/glx setups
case "$1" in
	"xorg")
		echo "* xorg gl/glx selected"

		# check for the existence of libglx_so, libGL_so_1_2 and friends
		# if none, nothing is necessary or the backups have been erased
		BACKUPS="/usr/lib/xorg/modules/extensions/libglx_so \
			/usr/lib/xorg/modules/extensions/libGLcore_so \
			/usr/lib/libGL_so_1_2"

		for F in $BACKUPS
		do
			if [ ! -e $F ]
			then
				infoMissing
				exit 1
			fi
		done

		# move the xorg backups back into place
		echo -n "libglx "
		rm -f /usr/lib/xorg/modules/extensions/libglx.so
		mv /usr/lib/xorg/modules/extensions/libglx{_so,.so}
		echo -n "libGLcore "
		rm -f /usr/lib/xorg/modules/extensions/libGLcore.so
		mv /usr/lib/xorg/modules/extensions/libGLcore{_so,.so}
		echo -n "libGL "
		mv /usr/lib/libGL{_so_1_2,.so.1.2}
		ln -sf libGL.so.1 /usr/lib/libGL.so
		;;

	"nvidia")
		echo "* nvidia gl/glx selected"

		# is an nvidia port installed?
		checkInstalled nvidia nvidia-legacy-96xx nvidia-legacy-71xx

		# get the .so version number
		NV_VER="`pkginfo -i | grep -e "^nvidia " -e "^nvidia-legacy-[[:digit:]][[:digit:]]xx " | awk '{ print $2 }' | sed -e 's/-[0-9]\+$//' | sed -e 's/-/\./' | cut -d- -f1`"

		# check for the existence of libglx_so and libGL_so_1_2
		# if none, move the xorg stuff out of the way for nvidia's
		if [ ! -e /usr/lib/xorg/modules/extensions/libglx_so -a ! -e \
			/usr/lib/libGL_so_1_2 ]
		then
			echo -n "libglx "
			mv /usr/lib/xorg/modules/extensions/libglx{.so,_so}
			ln -s libglx.so.$NV_VER \
				/usr/lib/xorg/modules/extensions/libglx.so
			echo -n "libGLcore "
			mv /usr/lib/xorg/modules/extensions/libGLcore{.so,_so}
			ln -s /usr/lib/libGLcore.so.$NV_VER \
				/usr/lib/xorg/modules/extensions/libGLcore.so
			echo -n "libGL "
			mv /usr/lib/libGL{.so.1.2,_so_1_2}
			rm /usr/lib/libGL.so{,.1}
			# nvidia's library versioning prevents ldconfig from creating
			# libGL.so and libGLcore.so
			ln -sf libGL.so.$NV_VER /usr/lib/libGL.so
			ln -sf libGLcore.so.$NV_VER /usr/lib/libGLcore.so
		else
			infoRevert
			exit 1
		fi
		;;

	"ati")
		echo "* ati gl/glx selected"

		# is the ati port installed?
		checkInstalled ati

		# check for the existence of libGL_so_1_2
		# if none, copy/move the xorg stuff out of the way for ati's
		if [ ! -e /usr/lib/libGL_so_1_2 ]
		then
			# we only need to move one library because it's the unique
			# that overwrites the xorg libGL, the other must be copied to be 
			# possible the revertion of the driver
			echo -n "libglx "
			cp /usr/lib/xorg/modules/extensions/libglx{.so,_so}
			echo -n "libGLcore "
			cp /usr/lib/xorg/modules/extensions/libGLcore{.so,_so}
			echo -n "libGL "
			mv /usr/lib/libGL{.so.1.2,_so_1_2}
			# according to ati port
			[ ! -L /usr/lib/libGL.so ] && \
				ln -sf libGL_so_1_2_ati /usr/lib/libGL.so
			[ ! -L /usr/lib/libGL.so.1 ] && \
				ln -sf libGL_so_1_2_ati /usr/lib/libGL.so.1
			[ ! -L /usr/lib/libGL.so.1.2 ] && \
				ln -sf libGL_so_1_2_ati /usr/lib/libGL.so.1.2
		else
			infoRevert
			exit 1
		fi
		;;

	*)
		infoUsage
		;;
esac

/sbin/ldconfig > /dev/null 2>&1

echo "done."

# End of file