Adding alternative handling for /usr/bin/lzip.

Signed-off-by: Daniel Baumann <daniel@debian.org>

debian/control

@@ -9,6 +9,7 @@ Homepage: http://www.nongnu.org/lzip/plzip.html
 Package: plzip
 Architecture: any
 Depends: ${misc:Depends}, ${shlibs:Depends}
+Breaks: lzip (<< 1.15~)
 Description: parallel, lossless data compressor based on the LZMA algorithm
  Lzip is a lossless data compressor based on the LZMA algorithm, with very safe
  integrity checking and a user interface similar to the one of gzip or bzip2.

debian/plzip.postinst

@@ -0,0 +1,25 @@
+#!/bin/sh
+
+set -e
+
+case "${1}" in
+	configure)
+		update-alternatives --quiet \
+			--install /usr/bin/lzip lzip /usr/bin/lzip.parallel 200 \
+			--slave /usr/share/info/lzip.info.gz lzip.info.gz /usr/share/info/lzip.parallel.info.gz \
+			--slave /usr/share/man/man1/lzip.1.gz lzip.1.gz /usr/share/man/man1/lzip.parallel.1.gz
+		;;
+
+	abort-upgrade|abort-remove|abort-deconfigure)
+
+		;;
+
+	*)
+		echo "postinst called with unknown argument \`${1}'" >&2
+		exit 1
+		;;
+esac
+
+#DEBHELPER#
+
+exit 0

debian/plzip.prerm

@@ -0,0 +1,22 @@
+#!/bin/sh
+
+set -e
+
+case "${1}" in
+	remove|upgrade|deconfigure)
+		update-alternatives --quiet --remove lzip /usr/bin/lzip.parallel
+		;;
+
+	failed-upgrade)
+
+		;;
+
+	*)
+		echo "prerm called with unknown argument \`${1}'" >&2
+		exit 1
+		;;
+esac
+
+#DEBHELPER#
+
+exit 0

debian/rules

@@ -11,6 +11,15 @@ override_dh_auto_install:
 	# removing unused files
 	rm -f debian/plzip/usr/share/info/dir*
 
+	# alernative handling
+	mv debian/plzip/usr/bin/plzip debian/plzip/usr/bin/lzip.parallel
+	mv debian/plzip/usr/share/info/plzip.info debian/plzip/usr/share/info/lzip.parallel.info
+	mv debian/plzip/usr/share/man/man1/plzip.1 debian/plzip/usr/share/man/man1/lzip.parallel.1
+
+	ln -s /usr/bin/lzip.parallel debian/plzip/usr/bin/plzip
+	ln -s /usr/share/info/lzip.parallel.info.gz debian/plzip/usr/share/info/plzip.info.gz
+	ln -s /usr/share/man/man1/lzip.parallel.1.gz debian/plzip/usr/share/man/man1/plzip.1.gz
+
 ifeq ($(DEB_BUILD_ARCH),sparc)
 override_dh_auto_test:
 	# disabled, see #608642 for more information