buildrpm: enable to start the script from anywhere

Previously the script worked only from the hg root.

contrib/buildrpm

@@ -1,88 +1,89
 #!/bin/sh
 #
 # Build a Mercurial RPM in place.
 #
 # Bryan O'Sullivan <[e-mail]>
 #
 # Tested on
 # - Fedora 10
 # - Fedora 11
 # - Centos 5.3 (with Fedora EPEL repo for asciidoc)
 
-HG="`dirname $0`/../hg"
-PYTHONPATH="`dirname $0`/../mercurial/pure"
+cd "`dirname $0`/.."
+HG="$PWD/hg"
+PYTHONPATH="$PWD/mercurial/pure"
 export PYTHONPATH
 
 root="`$HG root 2>/dev/null`"
 specfile=contrib/mercurial.spec
 
 if [ -z "$root" ]; then
     echo 'You are not inside a Mercurial repository!' 1>&2
     exit 1
 fi
 
 if $HG id -i | grep '+$' > /dev/null 2>&1; then
     echo -n "Your local changes will NOT be in the RPM. Continue [y/n] ? "
     read answer
     if echo $answer | grep -iv '^y'; then
         exit
     fi
 fi
 
 rpmdir=/tmp/"`basename $root | sed 's/ /_/'`"-rpm # FIXME: Insecure /tmp handling
 
 cd "$root"
 rm -rf $rpmdir
 mkdir -p $rpmdir/RPMS
 $HG clone -u . "$root" $rpmdir/BUILD
 
 if [ ! -f $specfile ]; then
     echo "Cannot find $specfile!" 1>&2
     exit 1
 fi
 
 tmpspec=/tmp/`basename "$specfile"`.$$ # FIXME: Insecure /tmp handling
 # make setup.py build the version string
 python setup.py build_py -c -d .
 hgversion=`$HG version | sed -ne 's/.*(version \(.*\))$/\1/p'`
 
 if echo $hgversion | grep -- '-' > /dev/null 2>&1; then
     # nightly build case, version is like 1.3.1+250-20b91f91f9ca
     version=`echo $hgversion | cut -d- -f1`
     release=`echo $hgversion | cut -d- -f2 | sed -e 's/+.*//'`
 else
     # official tag, version is like 1.3.1
     version=`echo $hgversion | sed -e 's/+.*//'`
     release='0'
 fi
 tip=`$HG -q tip`
 
 # Beat up the spec file
 sed -e 's,^Source:.*,Source: /dev/null,' \
     -e "s,^Version:.*,Version: $version," \
     -e "s,^Release:.*,Release: $release," \
     -e "s,^%prep.*,Changeset: $tip\n\0," \
     -e 's,^%setup.*,,' \
     $specfile > $tmpspec
 
 cat <<EOF >> $tmpspec
 %changelog
 * `LANG=en_US date +'%a %b %d %Y'` `$HG showconfig ui.username` $version-$release
 - Automatically built via $0
 
 EOF
 $HG log \
      --template '* {date|rfc822date} {author}\n- {desc|firstline}\n\n' \
      .hgtags \
   | sed -e 's/^\(\* [MTWFS][a-z][a-z]\), \([0-3][0-9]\) \([A-Z][a-z][a-z]\) /\1 \3 \2 /' \
         -e '/^\* [MTWFS][a-z][a-z] /{s/ [012][0-9]:[0-9][0-9]:[0-9][0-9] [+-][0-9]\{4\}//}' \
    >> $tmpspec
 
 rpmbuild --define "_topdir $rpmdir" -bb $tmpspec
 if [ $? = 0 ]; then
     rm -rf $tmpspec $rpmdir/BUILD
     mv $rpmdir/RPMS/*/* $rpmdir && rm -r $rpmdir/RPMS
     echo
     echo "Packages are in $rpmdir:"
     ls -l $rpmdir/*.rpm
 fi