#!/bin/sh -e
export LC_ALL=C

[ $# = 2 ] || pod2usage --exit=2 "$0"
rpm1="$1" rpm2="$2"

dir1= dir2=
cleanup()
{
	local rc=$?
	trap - EXIT
	rm -rf $dir1 $dir2
	exit $rc
}
trap cleanup EXIT HUP INT QUIT PIPE TERM
dir1=`mktemp -d -t rpmsymver.XXXXXXXX`
dir2=`mktemp -d -t rpmsymver.XXXXXXXX`

rpm -qp --provides "$rpm1" >$dir1/provides
rpm -qp --provides "$rpm2" >$dir2/provides

awk '$1~/^lib.*[.]so[^(]*$/{print$1}' $dir1/provides |sort -u >$dir1/libraries
awk '$1~/^lib.*[.]so[^(]*$/{print$1}' $dir2/provides |sort -u >$dir2/libraries

workdir=$dir1
comm -12 $dir1/libraries $dir2/libraries >$workdir/common
[ -s $workdir/common ] || { echo "$rpm1: no common libraries with $rpm2" >&2; exit 0; }

rpm2cpio "$rpm1" |(cd $dir1; cpio -idmu --quiet)
rpm2cpio "$rpm2" |(cd $dir2; cpio -idmu --quiet)

while read -r lib; do
	lib1="$(find $dir1 -name "$lib" |head -1)"
	lib2="$(find $dir2 -name "$lib" |head -1)"
	[ -f "$lib1" ] || { echo "lib=$lib lib1=$lib1" >&2; exit 1; }
	[ -f "$lib2" ] || { echo "lib=$lib lib2=$lib2" >&2; exit 1; }
	nm -D "$lib1" |awk 'NF==3{print$2,$3}' |sort -u >"$lib1".sym
	nm -D "$lib2" |awk 'NF==3{print$2,$3}' |sort -u >"$lib2".sym
	diff -U1 "$lib1".sym "$lib2".sym >$workdir/diff || [ $? = 1 ]
	sed	-e "s@$dir1@${rpm1##*/}@g" \
		-e "s@$dir2@${rpm2##*/}@g" $workdir/diff
done <$workdir/common

: <<'__EOF__'

=head1	NAME

rpmsymver - compare symbol versioning

=head1	SYNOPSIS

B<rpmsymver> I<librpm-1.0-alt1.i586.rpm> I<librpm-2.0-alt1.i586.rpm>

=cut

__EOF__