#!/usr/bin/bash
# This script can be invoked as follows:
#
# glibc-bench-compare [options] <BUILD> [BUILD]
#
# Options may be one of the following:
#
# -t		The BUILD arguments are task ids and not a version-release string
# -a ARCH	Do comparison for ARCH architecture
#
# If any of the above options are given, both BUILD arguments must be given.
# Otherwise, if only one BUILD is specified, then it is compared against the
# installed glibc.

# Silence the pushd/popd messages
pushd() {
	command pushd "$@" > /dev/null 2>&1
}

popd() {
	command popd "$@" > /dev/null 2>&1
}

# Clean up any downloaded files before we exit
trap "rm -rf /tmp/glibc-bench-compare.$BASHPID.*" EXIT

task=0
arch=$(uname -i)
options=0
path=0
installed=

# Look for any commandline options
while getopts ":tpa:" opt; do
	case $opt in
		p)
		path=1
		;;
		t)
		task=1
		options=1
		echo "Not implemented."
		exit 1
		;;
		a)
		arch=$OPTARG
		options=1
		;;
		*)
		;;
	esac
done

# Done, now shift all option arguments out.
shift $((OPTIND-1))

if [ $# -gt 2 ] || [ $# -eq 0 ] || [ $# -lt 2 -a $options -eq 1 ]; then
	echo "Usage: $0 [OPTIONS] <old> [new]"
	echo
	echo "OPTIONS:"
	echo -e "\t-t\tCompare two brew tasks"
	echo -e "\t-a ARCH\tGet rpms for the ARCH architecture"
	echo -e "\t-p\tCompare built rpms in two paths."
	echo -e "\t\tThis minimally needs glibc, glibc-common and glibc-benchtests"
	exit 1
fi

if [ -z $2 ]; then
	new="$1"
	old=$(rpm --queryformat "%{VERSION}-%{RELEASE}\n" -q glibc | head -1)
	installed=$old
else
	new="$2"
	old="$1"
fi

decompress_rpms() {
	# We were given a path to the rpms.  Figure out the version-release and
	# decompress the rpms.
	if [ -n $1 ]; then
		vr=$(rpm --queryformat="%{VERSION}-%{RELEASE}" -qp $1/glibc-2*.rpm | head -1)
		mkdir $vr && pushd $vr
	fi

	for r in $1*.rpm; do
		( rpm2cpio $r | cpio -di ) > /dev/null
	done

	if [ -n $1 ]; then
		popd
		echo $vr
	fi
}

# Get rpms for a build and decompress them
get_build() {
	echo "Processing build $1"
	mkdir $1 && pushd $1
	brew buildinfo "glibc-$1" |
	sed -n -e "s|/mnt/koji\(.\+$arch.\+\)|http://kojipkgs.fedoraproject.org\1|p" |
	while read url; do
		echo "Downloading $url"
		wget -q $url
	done
	decompress_rpms

	echo "Removing rpms"
	rm -f $1/*.rpm

	popd
}

# Run benchmarks for a build
run_bench() {
	if [ -z $1 ]; then
		make DETAILED=1 ver=$installed prefix= -f /usr/libexec/glibc-benchtests/bench.mk bench
	else
		make DETAILED=1 ver=$1 prefix=$PWD -f $1/usr/libexec/glibc-benchtests/bench.mk bench
	fi
}

# Get absolute paths if needed, since we will change into the working directory
# next.
if [ $path -eq 1 ]; then
	old_path=$(realpath $old)/
	new_path=$(realpath $new)/
fi

tmpdir=$(mktemp -p /tmp -d glibc-bench-compare.$$.XXXX)
pushd $tmpdir

# Get both builds.
if [ $path -eq 0 ]; then
	if [ -z $installed ]; then
		get_build $old
	fi
	get_build $new
else
	old=$(decompress_rpms $old_path)
	new=$(decompress_rpms $new_path)
fi

# make bench for each of those.
if [ -z $installed ]; then
	run_bench $old
else
	run_bench
fi
run_bench $new

# Now run the comparison script.
$old/usr/libexec/glibc-benchtests/compare_bench.py $old/usr/libexec/glibc-benchtests/benchout.schema.json \
	bench.$old.out bench.$new.out