#!/bin/sh

set -e

GIT_URL=git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
CONF_FILE=build_tools/git_test.conf

usage() {
	me=`basename $0`
	echo "$me: test building DAHDI vs. kernel from git"
	echo "Usage:"
	echo "  $me checkout <kerneldir>  Pull a kernel version into <kerneldir>"
	echo "  $me update                Update (pull) the kernel tree."
	echo "  $me setver <kernel_ver>   Set the kernel version"
	echo "  $me versions              Print available versions"
	echo "  $me version               Print current (kernel) version"
	echo "  $me version_driver        Print the version of DAHDI"
	echo "  $me build                 Test-build"
	echo "  $me git <git command>     Run <git command>"
	echo ""
	echo "  $me versions [pattern]    List available versions."
}

# Set a variable in $CONF_FILE
# The format of CONF_FILE is assumed to be:
# VAR=value
# in shell syntax. "value" may be quoted.
# "value should not contain a '|' character.
set_var() {
	var="$1"
	val="$2"
	if grep -q "^$var=" $CONF_FILE 2>/dev/null; then
		sed -i -e "s|^$var=.*|$var=\"$val\"|" $CONF_FILE
	else
		echo "$var=\"$val\"" >>$CONF_FILE
	fi
}

if [ -r "$CONF_FILE" ]; then . "$CONF_FILE"; fi

if echo "$CONF_FILE" | grep -qv '^/'; then
	# make CONF_FILE an absolute path:
	CONF_FILE="$PWD/$CONF_FILE"
fi

command="$1"

case "$command" in
	checkout) 
		kernel_dir="$2"
		cd "$kernel_dir"
		git clone $GIT_URL
		set_var kernel_dir "$kernel_dir/linux-2.6"
		;;
	update)
		cd "$kernel_dir"
		git pull
		;;
	git)
		cd "$kernel_dir"
		shift
		git "$@"
		;;
	versions)
		cd "$kernel_dir"
		git tag -l $2 | cut -c2-
		;;
	version)
		cd "$kernel_dir"
		echo "Configured: $kernel_ver"
		echo -n "Actual: "
		git describe | cut -c2-
		;;
	version_driver)
		version_h=include/dahdi/version.h
		make $version_h >/dev/null
		awk -F'"' '/DAHDI_VERSION/{print $2}' $version_h
		;;
	setver)
		kernel_ver="$2"
		tag="v$kernel_ver"
		cd "$kernel_dir"
		git-reset --hard "$tag"
		make distclean
		make defconfig modules_prepare
		set_var kernel_ver "$kernel_ver"
		;;
	test|build)
		# you can pass extra parameters to the make command in
		# two ways:
		# 1. Set the value of MAKE_PARAMS in git_test.conf .
		# 2. Any extra command-line parameter.
		shift
		make KSRC="$kernel_dir" KVERS=$kernel_ver $MAKE_PARAMS "$@"
		;;
	*)
		echo "$0: no such command $command. Aborting."
		usage
		exit 1
		;;
esac