libnx-xinerama1: also create libXinerama symlink in postinst (and remove in prerm.)

Due to the nx-x11-common package being a noarch/allarch package,
creating the symlink in nx-libs' Makefile will lead to the symlink
referencing the "default" architecture dpkg uses for building
noarch/allarch packages.

Incidentally, this worked fine for Debian, as amd64 seems to be the
default architecture. On Ubuntu, however, the default architecture up to
Vivid (15.04) was i386. For those builds, the symlink pointed to the 32
bit library of libNX_Xinerama.so.1 -- essentially breaking this feature.

Move the symlink creation to the arch-sensitive libnx-xinerama1 package.
The postinst and prerm scriptlets will work fine, unless someone
installs the i386 package version *after* the amd64 version. Given that
we already create symlinks to libNX_X11 and friends using that method,
no new regression is introduced. Strictly speaking that's a bug, but
we'll hopefully clean that up later...

3 files changed, 36 insertions, 29 deletions

diff --git a/Makefile b/Makefile
index 9f6442181..47efbde52 100644
--- a/Makefile
+++ b/Makefile
@@ -155,11 +155,12 @@ install-full:
 	    done; \
 
 	# Provide means for Xinerama support in NX/X2Go sessions. This
-	# This also requires two post-install symlinks:
-	# (DESTDIR)$(NXLIBDIR)/X11/Xinerama/libNX_X11.so.6 -> /usr/<libdir>/libX11.so.6
-	# (DESTDIR)$(NXLIBDIR)/X11/Xinerama/libNX_Xext.so.6 -> /usr/<libdir>/libXext.so.6
-	$(INSTALL_DIR) $(DESTDIR)$(NXLIBDIR)/X11/Xinerama
-	$(INSTALL_SYMLINK) $(USRLIBDIR)/libNX_Xinerama.so.1 $(DESTDIR)$(NXLIBDIR)/X11/Xinerama/libXinerama.so.1
+	# This also requires three post-install symlinks created by libnx-xinerama1:
+	# $(DESTDIR)$(NXLIBDIR)/X11/Xinerama/libNX_X11.so.6 -> /usr/<libdir>/libX11.so.6
+	# $(DESTDIR)$(NXLIBDIR)/X11/Xinerama/libNX_Xext.so.6 -> /usr/<libdir>/libXext.so.6
+	# $(DESTDIR)$(NXLIBDIR)/X11/Xinerama/libXinerama.so.1 -> /usr/<libdir>/libNX_Xinerama.so.1
+	# Only create the owned directory here for nx-x11-common.
+	$(INSTALL_DIR) $(DESTDIR)$(NXLIBDIR)/X11
 
 	$(INSTALL_DIR) $(DESTDIR)/$(ETCDIR_NX)
 	$(INSTALL_DIR) $(DESTDIR)/$(ETCDIR_X2GO)
diff --git a/debian/libnx-xinerama1.postinst.in b/debian/libnx-xinerama1.postinst.in
index c690be387..9b88c4b6f 100755
--- a/debian/libnx-xinerama1.postinst.in
+++ b/debian/libnx-xinerama1.postinst.in
@@ -26,14 +26,22 @@ case "$1" in
 
 		libdir=/usr/lib/#DEB_BUILD_MULTIARCH#
 
-		rm -f /usr/lib/nx/X11/Xinerama/libNX_X11.so.6
-		rm -f /usr/lib/nx/X11/Xinerama/libNX_Xext.so.6
+		# Already existent files and directories are not removed.
+		# Users will need to explicitly remove them and (re-) configure this package.
+
+		if test ! -e /usr/lib/nx/X11/Xinerama; then
+			install -d -m 755 /usr/lib/nx/X11/Xinerama
+		fi
+
 		if test -e $libdir/libX11.so.6; then
 			ln -s $libdir/libX11.so.6 /usr/lib/nx/X11/Xinerama/libNX_X11.so.6
 		fi
 		if test -e $libdir/libXext.so.6; then
 			ln -s $libdir/libXext.so.6 /usr/lib/nx/X11/Xinerama/libNX_Xext.so.6
 		fi
+		if test -e $libdir/libNX_Xinerama.so.1; then
+			ln -s $libdir/libNX_Xinerama.so.1 /usr/lib/nx/X11/Xinerama/libXinerama.so.1
+		fi
 	;;
 
 	abort-upgrade|abort-remove|abort-deconfigure)
diff --git a/debian/libnx-xinerama1.prerm b/debian/libnx-xinerama1.prerm
index 3fcd330e6..91105d0f8 100755
--- a/debian/libnx-xinerama1.prerm
+++ b/debian/libnx-xinerama1.prerm
@@ -1,37 +1,35 @@
 #!/bin/sh
-# postrm script for x2goserver-fmbindings
+# prerm script for libnx-xinerama1
 #
 # see: dh_installdeb(1)
-
-set -e
-
 # summary of how this script can be called:
-#        * <postrm> `remove'
-#        * <postrm> `purge'
-#        * <old-postrm> `upgrade' <new-version>
-#        * <new-postrm> `failed-upgrade' <old-version>
-#        * <new-postrm> `abort-install'
-#        * <new-postrm> `abort-install' <old-version>
-#        * <new-postrm> `abort-upgrade' <old-version>
-#        * <disappearer's-postrm> `disappear' <overwriter>
-#          <overwriter-version>
+#        * <prerm> `remove'
+#        * <old-prerm> `upgrade' <new-version>
+#        * <new-prerm> `failed-upgrade' <old-version>
+#        * <conflictor's-prerm> `remove' `in-favour' <package> <new-version>
+#        * <deconfigured's-prerm> `deconfigure' `in-favour'
+#        <package-being-installed> <version> `removing'
+#        <conflicting-package> <version>
 # for details, see http://www.debian.org/doc/debian-policy/ or
 # the debian-policy package
 
+set -e
+
+
 
 case "$1" in
-	purge|remove|upgrade|failed-upgrade|abort-install|abort-upgrade|disappear)
-		if test -e /usr/lib/nx/X11/Xinerama/libNX_X11.so.6; then
-			rm -f /usr/lib/nx/X11/Xinerama/libNX_X11.so.6
-		fi
-		if test -e /usr/lib/nx/X11/Xinerama/libNX_Xext.so.6; then
-			rm -f /usr/lib/nx/X11/Xinerama/libNX_Xext.so.6
+	remove)
+		if test -d /usr/lib/nx/X11/Xinerama; then
+			rm -rf /usr/lib/nx/X11/Xinerama
 		fi
-	;;
+		;;
+	deconfigure|upgrade|failed-upgrade)
+		:
+		;;
 	*)
-		echo "postrm called with unknown argument \`$1'" >&2
+		echo "prerm called with unknown argument \`$1'" >&2
 		exit 1
-	;;
+		;;
 esac
 
 # dh_installdeb will replace this with shell code automatically