revlog: generate trivial deltas against null revision
To avoid extra memory usage and performance issues with large files,
generate a trivial delta header for deltas against the null revision
rather than calling the usual delta generator.
We append the delta header to meta rather than prepending it to data
to avoid a large allocate and copy.
#!/bin/sh
#
# Build a Mercurial RPM in place.
#
# Bryan O'Sullivan <bos@serpentine.com>
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
rpmdir=/tmp/"`basename $root | sed 's/ /_/'`"-rpm
cd "$root"
rm -rf $rpmdir
mkdir -p $rpmdir/RPMS
hg clone "$root" $rpmdir/BUILD
if [ ! -f $specfile ]; then
echo "Cannot find $specfile!" 1>&2
exit 1
fi
tmpspec=/tmp/`basename "$specfile"`.$$
# Use the most recent tag as the version.
version=`hg tags | perl -e 'while(<STDIN>){if(/^(\d\S+)/){print$1;exit}}'`
# Compute the release number as the difference in revision numbers
# between the tip and the most recent tag.
release=`hg tags | perl -e 'while(<STDIN>){($tag,$id)=/^(\S+)\s+(\d+)/;if($tag eq "tip"){$tip = $id}elsif($tag=~/^\d/){print $tip-$id+1;exit}}'`
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
* `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"
fi