tools/dev/p4vm/install-p4-tools.sh - onos - Gitiles

 #!/usr/bin/env bash
 # -----------------------------------------------------------------------------
 # Builds and installs all tools needed for developing and testing P4 support in
 # ONOS.
 #
 # Tested on Ubuntu 14.04 and 16.04.
 #
 # Recommended minimum system requirements:
 # 4 GB of RAM
 # 2 cores
 # 8 GB free hard drive space (~4 GB to build everything)
 #
 # To execute up to a given step, pass the step name as the first argument. For
 # example, to install PI, but not BMv2, p4c, etc:
 #   ./install-p4-tools.sh PI
 # -----------------------------------------------------------------------------

 # Exit on errors.
 set -e

 BUILD_DIR=~/p4tools
 # in case BMV2_COMMIT value is updated, the same variable in
 # protocols/bmv2/thrift-api/BUCK file should also be updated
 BMV2_COMMIT="a3f0ebe4c0f10a656f8aa1ad68cb20402a62b0ee"
 PI_COMMIT="7e94b025bac6db63bc8534e5dd21a008984e38bc"
 P4C_COMMIT="2d089af757212a057c6690998861ef67439305f4"
 PROTOBUF_COMMIT="tags/v3.2.0"
 GRPC_COMMIT="tags/v1.3.2"
 LIBYANG_COMMIT="v0.14-r1"
 SYSREPO_COMMIT="v0.7.2"

 NUM_CORES=`grep -c ^processor /proc/cpuinfo`

 # If false, build tools without debug features to improve throughput of BMv2 and
 # reduce CPU/memory footprint.
 DEBUG_FLAGS=${DEBUG_FLAGS:-true}

 # Execute up to the given step (first argument), or all if not defined.
 LAST_STEP=${1:-all}

 function do_requirements {
     sudo apt update
     sudo apt-get install -y --no-install-recommends \
         autoconf \
         automake \
         bison \
         build-essential \
         cmake \
         cpp \
         curl \
         flex \
         git \
         libavl-dev \
         libboost-dev \
         libboost-program-options-dev \
         libboost-system-dev \
         libboost-filesystem-dev \
         libboost-thread-dev \
         libboost-filesystem-dev \
         libboost-program-options-dev \
         libboost-system-dev \
         libboost-test-dev \
         libboost-thread-dev \
         libc6-dev \
         libev-dev \
         libevent-dev \
         libffi-dev \
         libfl-dev \
         libgc-dev \
         libgc1c2 \
         libgflags-dev \
         libgmp-dev \
         libgmp10 \
         libgmpxx4ldbl \
         libjudy-dev \
         libpcap-dev \
         libpcre3-dev \
         libreadline6 \
         libreadline6-dev \
         libssl-dev \
         libtool \
         make \
         mktemp \
         pkg-config \
         protobuf-c-compiler \
         python2.7 \
         python2.7-dev \
         tcpdump \
         wget \
         unzip

     sudo -H pip install setuptools cffi ipaddr pypcap
 }

 function do_requirements_1404 {
     sudo apt install -y python-software-properties software-properties-common
     sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
     sudo add-apt-repository -y ppa:george-edison55/cmake-3.x
     sudo apt update
     sudo apt install -y \
         dpkg-dev \
         g++-4.9 \
         gcc-4.9 \
         cmake \
         libbz2-dev

     # Needed for p4c.
     sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.9 50
     sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.9 50

     if [ -z "$(ldconfig -p | grep libboost_iostreams.so.1.58.0)"  ]; then
         do_boost
     fi
 }

 function do_requirements_1604 {
     sudo apt-get update
     sudo apt-get install -y --no-install-recommends \
         ca-certificates \
         g++ \
         libboost-iostreams1.58-dev \
         libprotobuf-c-dev
 }

 function do_boost {
     cd ${BUILD_DIR}
     wget https://sourceforge.net/projects/boost/files/boost/1.58.0/boost_1_58_0.tar.bz2/download -O boost_1_58_0.tar.bz2
     tar --bzip2 -xf boost_1_58_0.tar.bz2
     cd boost_1_58_0

     ./bootstrap.sh --with-libraries=iostreams
     sudo ./b2 install
     sudo ldconfig

     cd ..
     sudo rm -rf boost_1_58_0
 }

 function do_protobuf-c {
     cd ${BUILD_DIR}
     git clone https://github.com/protobuf-c/protobuf-c.git
     cd protobuf-c

     ./autogen.sh
     ./configure --prefix=/usr
     make -j${NUM_CORES}
     sudo make install
     sudo ldconfig

     cd ..
     sudo rm -rf protobuf-c
 }

 function do_protobuf {
     cd ${BUILD_DIR}
     if [ ! -d protobuf ]; then
       git clone https://github.com/google/protobuf.git
     fi
     cd protobuf
     git fetch
     git checkout ${PROTOBUF_COMMIT}

     export CFLAGS="-Os"
     export CXXFLAGS="-Os"
     export LDFLAGS="-Wl,-s"
     ./autogen.sh
     ./configure --prefix=/usr
     make -j${NUM_CORES}
     sudo make install
     sudo ldconfig
     unset CFLAGS CXXFLAGS LDFLAGS

     cd python
     sudo python setup.py install --cpp_implementation
 }

 function do_grpc {
     cd ${BUILD_DIR}
     if [ ! -d grpc ]; then
       git clone https://github.com/grpc/grpc.git
     fi
     cd grpc
     git fetch
     git checkout ${GRPC_COMMIT}
     git submodule update --init

     export LDFLAGS="-Wl,-s"
     make -j${NUM_CORES}
     sudo make install
     sudo ldconfig
     unset LDFLAGS

     sudo pip install -r requirements.txt
     sudo pip install .
 }

 function do_libyang {
     cd ${BUILD_DIR}
     if [ ! -d libyang ]; then
       git clone https://github.com/CESNET/libyang.git
     fi
     cd libyang
     git fetch
     git checkout ${LIBYANG_COMMIT}

     mkdir -p build
     cd build
     cmake ..
     make -j${NUM_CORES}
     sudo make install
     sudo ldconfig
 }

 function do_sysrepo_deps {
     RELEASE=`lsb_release -rs`
     if version_ge $RELEASE 14.04 && [ -z "$(ldconfig -p | grep libprotobuf-c)"  ]; then
         do_protobuf-c
     fi
 }

 function do_sysrepo {
     do_sysrepo_deps

     cd ${BUILD_DIR}
     if [ ! -d sysrepo ]; then
       git clone https://github.com/sysrepo/sysrepo.git
     fi
     cd sysrepo
     git fetch
     git checkout ${SYSREPO_COMMIT}

     mkdir -p build
     cd build
     cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_EXAMPLES=Off \
         -DCALL_TARGET_BINS_DIRECTLY=Off ..
     make -j${NUM_CORES}
     sudo make install
     sudo ldconfig
 }

 function checkout_bmv2 {
     cd ${BUILD_DIR}
     if [ ! -d bmv2 ]; then
         git clone https://github.com/p4lang/behavioral-model.git bmv2
     fi
     cd bmv2
     git fetch
     git checkout ${BMV2_COMMIT}
 }

 function do_pi_bmv2_deps {
     checkout_bmv2
     # From bmv2's install_deps.sh.
     # Nanomsg is required also by PI.
     tmpdir=`mktemp -d -p .`
     cd ${tmpdir}
     bash ../travis/install-thrift.sh
     bash ../travis/install-nanomsg.sh
     sudo ldconfig
     bash ../travis/install-nnpy.sh
     cd ..
     sudo rm -rf $tmpdir
 }

 function do_PI {
     cd ${BUILD_DIR}
     if [ ! -d PI ]; then
         git clone https://github.com/p4lang/PI.git
     fi
     cd PI
     git fetch
     git checkout ${PI_COMMIT}
     git submodule update --init --recursive

     ./autogen.sh
     # FIXME: re-enable --with-sysrepo when gNMI support becomes more stable
     # ./configure --with-proto --with-sysrepo 'CXXFLAGS=-O0 -g'
     if [ "${DEBUG_FLAGS}" = true ] ; then
         ./configure --with-proto "CXXFLAGS=-O0 -g"
     else
         ./configure --with-proto
     fi
     make -j${NUM_CORES}
     sudo make install
     sudo ldconfig

     # FIXME: re-enable when gNMI support becomes more stable
     # sudo proto/sysrepo/install_yangs.sh
 }

 function do_bmv2 {
     checkout_bmv2

     ./autogen.sh
     if [ "${DEBUG_FLAGS}" = true ] ; then
         ./configure --with-pi --enable-debugger --disable-elogger "CXXFLAGS=-O0 -g"
     else
         ./configure --with-pi --disable-logging-macros --disable-elogger --without-nanomsg
     fi
     make -j${NUM_CORES}
     sudo make install
     sudo ldconfig

     # Simple_switch_grpc target
     cd targets/simple_switch_grpc
     ./autogen.sh

     if [ "${DEBUG_FLAGS}" = true ] ; then
         ./configure --with-thrift "CXXFLAGS=-O0 -g"
     else
         ./configure --with-thrift
     fi
     # FIXME: re-enable --with-sysrepo when gNMI support becomes more stable
     # ./configure --with-sysrepo --with-thrift 'CXXFLAGS=-O0 -g'
     make -j${NUM_CORES}
     sudo make install
     sudo ldconfig
 }

 function do_p4c {
     cd ${BUILD_DIR}
     if [ ! -d p4c ]; then
         git clone https://github.com/p4lang/p4c.git
     fi
     cd p4c
     git fetch
     git checkout ${P4C_COMMIT}
     git submodule update --init --recursive

     mkdir -p build
     cd build
     cmake ..
     make -j${NUM_CORES}
     sudo make install
     sudo ldconfig
 }

 function do_scapy-vxlan {
     cd ${BUILD_DIR}
     if [ ! -d scapy-vxlan ]; then
         git clone https://github.com/p4lang/scapy-vxlan.git
     fi
     cd scapy-vxlan

     git pull origin master

     sudo python setup.py install
 }

 function do_ptf {
     cd ${BUILD_DIR}
     if [ ! -d ptf ]; then
         git clone https://github.com/p4lang/ptf.git
     fi
     cd ptf
     git pull origin master

     sudo python setup.py install
 }

 function check_commit {
     if [ ! -e $2 ]; then
         return 0 # true
     fi
     if [[ $(< $2) != "$1" ]]; then
         return 0 # true
     fi
     return 1 # false
 }

 # The following is borrowed from Mininet's util/install.sh
 function version_ge {
     # sort -V sorts by *version number*
     latest=`printf "$1\n$2" | sort -V | tail -1`
     # If $1 is latest version, then $1 >= $2
     [ "$1" == "$latest" ]
 }

 MUST_DO_ALL=false
 DID_REQUIREMENTS=false
 function check_and_do {
     # Check if the latest built commit is the same we are trying to build now,
     # or if all projects must be built. If true builds this project.
     commit_id="$1"
     proj_dir="$2"
     func_name="$3"
     step_name="$4"
     commit_file=${BUILD_DIR}/${proj_dir}/.last_built_commit_${step_name}
     if [ ${MUST_DO_ALL} = true ] \
         || check_commit ${commit_id} ${commit_file}; then
         echo "#"
         echo "# Building ${step_name} (${commit_id})"
         echo "#"
         # Print commands used to install to aid debugging
         set -x
         if ! ${DID_REQUIREMENTS} = true; then
             do_requirements
             # TODO consider other Linux distros; presently this script assumes
             # that it is running on Ubuntu.
             RELEASE=`lsb_release -rs`
             if version_ge $RELEASE 16.04; then
                 do_requirements_1604
             elif version_ge $RELEASE 14.04; then
                 do_requirements_1404
             else
                 echo "Ubuntu version $RELEASE is not supported"
                 exit 1
             fi
             DID_REQUIREMENTS=true
         fi
         eval ${func_name}
         echo ${commit_id} > ${commit_file}
         # Build all next projects as they might depend on this one.
         MUST_DO_ALL=true
         # Disable printing to reduce output
         set +x
     else
         echo "${step_name} is up to date (commit ${commit_id})"
     fi
     # Exit if last step.
     if [ ${step_name} = ${LAST_STEP} ]; then
         exit
     fi
 }

 mkdir -p ${BUILD_DIR}
 cd ${BUILD_DIR}
 # In dependency order.
 check_and_do ${PROTOBUF_COMMIT} protobuf do_protobuf protobuf
 check_and_do ${GRPC_COMMIT} grpc do_grpc grpc
 # FIXME: re-enable when gNMI support becomes more stable
 # check_and_do ${LIBYANG_COMMIT} libyang do_libyang libyang
 # check_and_do ${SYSREPO_COMMIT} sysrepo do_sysrepo sysrepo
 check_and_do ${BMV2_COMMIT} bmv2 do_pi_bmv2_deps bmv2-deps
 check_and_do ${PI_COMMIT} PI do_PI PI
 check_and_do ${BMV2_COMMIT} bmv2 do_bmv2 bmv2
 check_and_do ${P4C_COMMIT} p4c do_p4c p4c
 check_and_do master scapy-vxlan do_scapy-vxlan scapy-vxlan
 check_and_do master ptf do_ptf ptf

 echo "Done!"
	#!/usr/bin/env bash
	# -----------------------------------------------------------------------------
	# Builds and installs all tools needed for developing and testing P4 support in
	# ONOS.
	#
	# Tested on Ubuntu 14.04 and 16.04.
	#
	# Recommended minimum system requirements:
	# 4 GB of RAM
	# 2 cores
	# 8 GB free hard drive space (~4 GB to build everything)
	#
	# To execute up to a given step, pass the step name as the first argument. For
	# example, to install PI, but not BMv2, p4c, etc:
	# ./install-p4-tools.sh PI
	# -----------------------------------------------------------------------------

	# Exit on errors.
	set -e

	BUILD_DIR=~/p4tools
	# in case BMV2_COMMIT value is updated, the same variable in
	# protocols/bmv2/thrift-api/BUCK file should also be updated
	BMV2_COMMIT="a3f0ebe4c0f10a656f8aa1ad68cb20402a62b0ee"
	PI_COMMIT="7e94b025bac6db63bc8534e5dd21a008984e38bc"
	P4C_COMMIT="2d089af757212a057c6690998861ef67439305f4"
	PROTOBUF_COMMIT="tags/v3.2.0"
	GRPC_COMMIT="tags/v1.3.2"
	LIBYANG_COMMIT="v0.14-r1"
	SYSREPO_COMMIT="v0.7.2"

	NUM_CORES=`grep -c ^processor /proc/cpuinfo`

	# If false, build tools without debug features to improve throughput of BMv2 and
	# reduce CPU/memory footprint.
	DEBUG_FLAGS=${DEBUG_FLAGS:-true}

	# Execute up to the given step (first argument), or all if not defined.
	LAST_STEP=${1:-all}

	function do_requirements {
	sudo apt update
	sudo apt-get install -y --no-install-recommends \
	autoconf \
	automake \
	bison \
	build-essential \
	cmake \
	cpp \
	curl \
	flex \
	git \
	libavl-dev \
	libboost-dev \
	libboost-program-options-dev \
	libboost-system-dev \
	libboost-filesystem-dev \
	libboost-thread-dev \
	libboost-filesystem-dev \
	libboost-program-options-dev \
	libboost-system-dev \
	libboost-test-dev \
	libboost-thread-dev \
	libc6-dev \
	libev-dev \
	libevent-dev \
	libffi-dev \
	libfl-dev \
	libgc-dev \
	libgc1c2 \
	libgflags-dev \
	libgmp-dev \
	libgmp10 \
	libgmpxx4ldbl \
	libjudy-dev \
	libpcap-dev \
	libpcre3-dev \
	libreadline6 \
	libreadline6-dev \
	libssl-dev \
	libtool \
	make \
	mktemp \
	pkg-config \
	protobuf-c-compiler \
	python2.7 \
	python2.7-dev \
	tcpdump \
	wget \
	unzip

	sudo -H pip install setuptools cffi ipaddr pypcap
	}

	function do_requirements_1404 {
	sudo apt install -y python-software-properties software-properties-common
	sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
	sudo add-apt-repository -y ppa:george-edison55/cmake-3.x
	sudo apt update
	sudo apt install -y \
	dpkg-dev \
	g++-4.9 \
	gcc-4.9 \
	cmake \
	libbz2-dev

	# Needed for p4c.
	sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.9 50
	sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.9 50

	if [ -z "$(ldconfig -p \| grep libboost_iostreams.so.1.58.0)" ]; then
	do_boost
	fi
	}

	function do_requirements_1604 {
	sudo apt-get update
	sudo apt-get install -y --no-install-recommends \
	ca-certificates \
	g++ \
	libboost-iostreams1.58-dev \
	libprotobuf-c-dev
	}

	function do_boost {
	cd ${BUILD_DIR}
	wget https://sourceforge.net/projects/boost/files/boost/1.58.0/boost_1_58_0.tar.bz2/download -O boost_1_58_0.tar.bz2
	tar --bzip2 -xf boost_1_58_0.tar.bz2
	cd boost_1_58_0

	./bootstrap.sh --with-libraries=iostreams
	sudo ./b2 install
	sudo ldconfig

	cd ..
	sudo rm -rf boost_1_58_0
	}

	function do_protobuf-c {
	cd ${BUILD_DIR}
	git clone https://github.com/protobuf-c/protobuf-c.git
	cd protobuf-c

	./autogen.sh
	./configure --prefix=/usr
	make -j${NUM_CORES}
	sudo make install
	sudo ldconfig

	cd ..
	sudo rm -rf protobuf-c
	}

	function do_protobuf {
	cd ${BUILD_DIR}
	if [ ! -d protobuf ]; then
	git clone https://github.com/google/protobuf.git
	fi
	cd protobuf
	git fetch
	git checkout ${PROTOBUF_COMMIT}

	export CFLAGS="-Os"
	export CXXFLAGS="-Os"
	export LDFLAGS="-Wl,-s"
	./autogen.sh
	./configure --prefix=/usr
	make -j${NUM_CORES}
	sudo make install
	sudo ldconfig
	unset CFLAGS CXXFLAGS LDFLAGS

	cd python
	sudo python setup.py install --cpp_implementation
	}

	function do_grpc {
	cd ${BUILD_DIR}
	if [ ! -d grpc ]; then
	git clone https://github.com/grpc/grpc.git
	fi
	cd grpc
	git fetch
	git checkout ${GRPC_COMMIT}
	git submodule update --init

	export LDFLAGS="-Wl,-s"
	make -j${NUM_CORES}
	sudo make install
	sudo ldconfig
	unset LDFLAGS

	sudo pip install -r requirements.txt
	sudo pip install .
	}

	function do_libyang {
	cd ${BUILD_DIR}
	if [ ! -d libyang ]; then
	git clone https://github.com/CESNET/libyang.git
	fi
	cd libyang
	git fetch
	git checkout ${LIBYANG_COMMIT}

	mkdir -p build
	cd build
	cmake ..
	make -j${NUM_CORES}
	sudo make install
	sudo ldconfig
	}

	function do_sysrepo_deps {
	RELEASE=`lsb_release -rs`
	if version_ge $RELEASE 14.04 && [ -z "$(ldconfig -p \| grep libprotobuf-c)" ]; then
	do_protobuf-c
	fi
	}

	function do_sysrepo {
	do_sysrepo_deps

	cd ${BUILD_DIR}
	if [ ! -d sysrepo ]; then
	git clone https://github.com/sysrepo/sysrepo.git
	fi
	cd sysrepo
	git fetch
	git checkout ${SYSREPO_COMMIT}

	mkdir -p build
	cd build
	cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_EXAMPLES=Off \
	-DCALL_TARGET_BINS_DIRECTLY=Off ..
	make -j${NUM_CORES}
	sudo make install
	sudo ldconfig
	}

	function checkout_bmv2 {
	cd ${BUILD_DIR}
	if [ ! -d bmv2 ]; then
	git clone https://github.com/p4lang/behavioral-model.git bmv2
	fi
	cd bmv2
	git fetch
	git checkout ${BMV2_COMMIT}
	}

	function do_pi_bmv2_deps {
	checkout_bmv2
	# From bmv2's install_deps.sh.
	# Nanomsg is required also by PI.
	tmpdir=`mktemp -d -p .`
	cd ${tmpdir}
	bash ../travis/install-thrift.sh
	bash ../travis/install-nanomsg.sh
	sudo ldconfig
	bash ../travis/install-nnpy.sh
	cd ..
	sudo rm -rf $tmpdir
	}

	function do_PI {
	cd ${BUILD_DIR}
	if [ ! -d PI ]; then
	git clone https://github.com/p4lang/PI.git
	fi
	cd PI
	git fetch
	git checkout ${PI_COMMIT}
	git submodule update --init --recursive

	./autogen.sh
	# FIXME: re-enable --with-sysrepo when gNMI support becomes more stable
	# ./configure --with-proto --with-sysrepo 'CXXFLAGS=-O0 -g'
	if [ "${DEBUG_FLAGS}" = true ] ; then
	./configure --with-proto "CXXFLAGS=-O0 -g"
	else
	./configure --with-proto
	fi
	make -j${NUM_CORES}
	sudo make install
	sudo ldconfig

	# FIXME: re-enable when gNMI support becomes more stable
	# sudo proto/sysrepo/install_yangs.sh
	}

	function do_bmv2 {
	checkout_bmv2

	./autogen.sh
	if [ "${DEBUG_FLAGS}" = true ] ; then
	./configure --with-pi --enable-debugger --disable-elogger "CXXFLAGS=-O0 -g"
	else
	./configure --with-pi --disable-logging-macros --disable-elogger --without-nanomsg
	fi
	make -j${NUM_CORES}
	sudo make install
	sudo ldconfig

	# Simple_switch_grpc target
	cd targets/simple_switch_grpc
	./autogen.sh

	if [ "${DEBUG_FLAGS}" = true ] ; then
	./configure --with-thrift "CXXFLAGS=-O0 -g"
	else
	./configure --with-thrift
	fi
	# FIXME: re-enable --with-sysrepo when gNMI support becomes more stable
	# ./configure --with-sysrepo --with-thrift 'CXXFLAGS=-O0 -g'
	make -j${NUM_CORES}
	sudo make install
	sudo ldconfig
	}

	function do_p4c {
	cd ${BUILD_DIR}
	if [ ! -d p4c ]; then
	git clone https://github.com/p4lang/p4c.git
	fi
	cd p4c
	git fetch
	git checkout ${P4C_COMMIT}
	git submodule update --init --recursive

	mkdir -p build
	cd build
	cmake ..
	make -j${NUM_CORES}
	sudo make install
	sudo ldconfig
	}

	function do_scapy-vxlan {
	cd ${BUILD_DIR}
	if [ ! -d scapy-vxlan ]; then
	git clone https://github.com/p4lang/scapy-vxlan.git
	fi
	cd scapy-vxlan

	git pull origin master

	sudo python setup.py install
	}

	function do_ptf {
	cd ${BUILD_DIR}
	if [ ! -d ptf ]; then
	git clone https://github.com/p4lang/ptf.git
	fi
	cd ptf
	git pull origin master

	sudo python setup.py install
	}

	function check_commit {
	if [ ! -e $2 ]; then
	return 0 # true
	fi
	if [[ $(< $2) != "$1" ]]; then
	return 0 # true
	fi
	return 1 # false
	}

	# The following is borrowed from Mininet's util/install.sh
	function version_ge {
	# sort -V sorts by version number
	latest=`printf "$1\n$2" \| sort -V \| tail -1`
	# If $1 is latest version, then $1 >= $2
	[ "$1" == "$latest" ]
	}

	MUST_DO_ALL=false
	DID_REQUIREMENTS=false
	function check_and_do {
	# Check if the latest built commit is the same we are trying to build now,
	# or if all projects must be built. If true builds this project.
	commit_id="$1"
	proj_dir="$2"
	func_name="$3"
	step_name="$4"
	commit_file=${BUILD_DIR}/${proj_dir}/.last_built_commit_${step_name}
	if [ ${MUST_DO_ALL} = true ] \
	\|\| check_commit ${commit_id} ${commit_file}; then
	echo "#"
	echo "# Building ${step_name} (${commit_id})"
	echo "#"
	# Print commands used to install to aid debugging
	set -x
	if ! ${DID_REQUIREMENTS} = true; then
	do_requirements
	# TODO consider other Linux distros; presently this script assumes
	# that it is running on Ubuntu.
	RELEASE=`lsb_release -rs`
	if version_ge $RELEASE 16.04; then
	do_requirements_1604
	elif version_ge $RELEASE 14.04; then
	do_requirements_1404
	else
	echo "Ubuntu version $RELEASE is not supported"
	exit 1
	fi
	DID_REQUIREMENTS=true
	fi
	eval ${func_name}
	echo ${commit_id} > ${commit_file}
	# Build all next projects as they might depend on this one.
	MUST_DO_ALL=true
	# Disable printing to reduce output
	set +x
	else
	echo "${step_name} is up to date (commit ${commit_id})"
	fi
	# Exit if last step.
	if [ ${step_name} = ${LAST_STEP} ]; then
	exit
	fi
	}

	mkdir -p ${BUILD_DIR}
	cd ${BUILD_DIR}
	# In dependency order.
	check_and_do ${PROTOBUF_COMMIT} protobuf do_protobuf protobuf
	check_and_do ${GRPC_COMMIT} grpc do_grpc grpc
	# FIXME: re-enable when gNMI support becomes more stable
	# check_and_do ${LIBYANG_COMMIT} libyang do_libyang libyang
	# check_and_do ${SYSREPO_COMMIT} sysrepo do_sysrepo sysrepo
	check_and_do ${BMV2_COMMIT} bmv2 do_pi_bmv2_deps bmv2-deps
	check_and_do ${PI_COMMIT} PI do_PI PI
	check_and_do ${BMV2_COMMIT} bmv2 do_bmv2 bmv2
	check_and_do ${P4C_COMMIT} p4c do_p4c p4c
	check_and_do master scapy-vxlan do_scapy-vxlan scapy-vxlan
	check_and_do master ptf do_ptf ptf

	echo "Done!"