builder: vagrant: introduce Vagrantfile

The contributor can make use of a VM box (arm64/amd64) using the
following Makefile rules: vagrant-up, vagrant-ssh, vagrant-halt and
vagrant-destroy.

One can override the ARCH env var:
make vagrant-up ARCH=arm64

Whether the override will work depends on the availability of online
boxes and compatibility of architecture and providers (vbox, parallels).

Tested in Darwin (M1) and Linux (amd64).

.gitignore

@@ -5,4 +5,5 @@ selftest/*/*-static
 selftest/*/*-dynamic
 selftest/uprobe/ctest
 selftest/uprobe/gotest
-testing/tracee
+testing/tracee
+.vagrant*

Makefile

@@ -7,8 +7,10 @@ HELPERS = ./helpers
 CC = gcc
 CLANG = clang
 GO = go
+VAGRANT = vagrant
 
-ARCH := $(shell uname -m | sed 's/x86_64/amd64/g; s/aarch64/arm64/g')
+HOSTOS = $(shell uname)
+ARCH ?= $(shell uname -m | sed 's/x86_64/amd64/g; s/aarch64/arm64/g')
 
 BTFFILE = /sys/kernel/btf/vmlinux
 BPFTOOL = $(shell which bpftool || /bin/false)
@@ -180,6 +182,26 @@ helpers-test-static-run: libbpfgo-static
 helpers-test-dynamic-run: libbpfgo-dynamic
 	sudo $(GO) test -v $(HELPERS)/...
 
+# vagrant
+
+VAGRANT_DIR = $(abspath ./builder)
+
+.PHONY: vagrant-up
+.PHONY: vagrant-destroy
+.PHONY: vagrant-halt
+.PHONY: vagrant-ssh
+
+vagrant-up: .vagrant-up
+vagrant-destroy: .vagrant-destroy
+vagrant-halt: .vagrant-halt
+vagrant-ssh: .vagrant-ssh
+
+.vagrant-%:
+	VAGRANT_VAGRANTFILE=$(VAGRANT_DIR)/Vagrantfile.ubuntu \
+		ARCH=$(ARCH) \
+		HOSTOS=$(HOSTOS) \
+		$(VAGRANT) $*
+
 # output
 
 $(OUTPUT):

builder/Vagrantfile.ubuntu

@@ -0,0 +1,41 @@
+ARCH = ENV["ARCH"] || "amd64"
+HOSTOS = ENV["HOSTOS"] || "undefined"
+
+if ! %w(amd64 arm64).include?(ARCH) then
+    puts "ERROR: ARCH #{ARCH} not supported"
+    abort
+end
+
+if ! %w(Linux Darwin).include?(HOSTOS) then
+    puts "ERROR: HOSTOS #{HOSTOS} not supported"
+    abort
+end
+
+VM_NAME = "libbpfgo_#{ARCH}_vm"
+VM_SOURCE = "/vagrant"
+
+Vagrant.configure("2") do |config|
+  case ARCH
+  when "amd64"
+    config.vm.box = "generic/ubuntu2004"
+  when "arm64"
+    config.vm.box = "jeffnoxon/ubuntu-20.04-arm64"
+  end
+
+  config.vm.synced_folder "./", "#{VM_SOURCE}"
+  config.ssh.extra_args = ["-t", "cd #{VM_SOURCE}; bash --login"]
+
+  case HOSTOS
+  when "Linux"
+    config.vm.provider "virtualbox" do |vb|
+      vb.name = VM_NAME
+    end
+  when "Darwin"
+    config.vm.provider "parallels" do |prl|
+      prl.name = VM_NAME
+    end
+  end
+
+  config.vm.provision :shell, inline: "ARCH=#{ARCH} #{VM_SOURCE}/builder/prepare-ubuntu.sh vagrant"
+  config.vm.provision :shell, inline: "echo FINISHED provision: now connect via ssh"
+end

builder/prepare-ubuntu.sh

@@ -0,0 +1,80 @@
+#!/bin/bash
+
+#
+# This shell script is meant to prepare a building/exec environment for libbpfgo.
+#
+
+die() {
+    echo "ERROR: ${*}"
+    exit 1
+}
+
+info() {
+    echo "INFO: ${*}"
+}
+
+USER="${1}"
+[ -z "${USER}" ] && USER="root"
+USERHOME=$(eval echo ~"${USER}")
+[ -d "${USERHOME}" ] || die "directory ${USERHOME} doesn't exist"
+
+[ -z "${GOVERSION}" ] && GOVERSION="1.17.13"
+[ -z "${ARCH}" ] && ARCH="amd64"
+
+CMDS="wget rm tar chown apt-get"
+for cmd in ${CMDS}; do
+    command -v "${cmd}" >/dev/null 2>&1 || die "missing required tool ${cmd}"
+done
+
+install_go() {
+    info "Installing Go ${GOVERSION}"
+
+    local file="go${GOVERSION}.linux-${ARCH}.tar.gz"
+    local link="https://golang.org/dl/${file}"
+    sudo wget --progress=bar:force "${link}" -P /tmp || die "could not download ${link}"
+
+    local dest="/usr/local"
+    sudo rm -rf "${dest}/go"
+    sudo tar -C "${dest}" -xzf "/tmp/${file}" || die "could not untar ${file} in ${dest}"
+    sudo chown -R root:root "${dest}/go" || die "could not chown"
+
+    local home_profile="${USERHOME}/.profile"
+    echo "export PATH=${PATH}:${dest}/go/bin" | sudo tee -a "${home_profile}"
+
+    info "Go ${GOVERSION} installed"
+}
+
+install_pkgs() {
+    # silence 'dpkg-preconfigure: unable to re-open stdin: No such file or directory'
+    export DEBIAN_FRONTEND=noninteractive
+
+    sudo -E apt-get update || die "coud not update package list"
+    for pkg in "${@}"
+    do
+      info "Installing ${pkg}"
+      sudo -E apt-get install -y "${pkg}" || die "could not install ${pkg}"
+      info "${pkg} installed"
+    done
+}
+
+# startup
+
+info "Starting preparation"
+
+install_go
+
+install_pkgs \
+    coreutils bsdutils findutils \
+    build-essential pkgconf \
+    llvm-12 clang-12 \
+    clang-format-12 \
+    linux-headers-generic linux-tools-"$(uname -r)" \
+    zlib1g-dev libelf-dev libbpf-dev
+
+for tool in "clang" "llc" "llvm-strip" "clang-format"
+do
+    sudo rm -f /usr/bin/${tool}
+    sudo ln -s /usr/bin/${tool}-12 /usr/bin/${tool}
+done
+
+info "Preparation finished"