build latest Mrcurial Centos 6.5

#!/bin/sh

### INFO
# http://stackoverflow.com/questions/14009241/cannot-build-mercurial-from-sources-in-centos
# http://www.cyberciti.biz/tips/bash-shell-parameter-substitution-2.html
###

ARCHIVE=mercurial-3.4-rc.tar.gz

PROG_VERSION="${ARCHIVE#*-}"  # Strip pattern from top first - symbol.
PROG_VERSION="${PROG_VERSION%.tar.gz}"  # Remove pattern from back of $PROG_VERSION variable.
PROG_RELEASE="${PROG_VERSION#*-}"  # Remove pattern from back of $PROG_VERSION variable.
PROG_VERSION="${PROG_VERSION%-*}"  # Remove pattern from back of $PROG_VERSION variable.

tar -xzf $ARCHIVE --strip-components=2 $(basename $ARCHIVE .tar.gz)/contrib/mercurial.spec
sed -i'' 's/Version: .*/Version: '$PROG_VERSION'/' mercurial.spec
sed -i'' 's/Release: .*/Release: '$PROG_RELEASE'/' mercurial.spec

[ ! -d /root/rpmbuild/SOURCES ] && mkdir -p /root/rpmbuild/SOURCES
cp $ARCHIVE /root/rpmbuild/SOURCES
rpmbuild -v -bb --without debuginfo --target=$(uname -m) mercurial.spec