path: root/bin/cross_toolchain.rb

#!/usr/bin/env ruby
# This Source Code Form is subject to the terms of the Mozilla Public License,
# v. 2.0. If a copy of the MPL was not distributed with this file, You can
# obtain one at https://mozilla.org/MPL/2.0/. -}

# frozen_string_literal: true

require 'uri'
require 'net/http'
require 'open3'
require 'etc'
require 'fileutils'
require 'pathname'
require 'term/ansicolor'

BINUTILS_VERSION = '2.45'
GLIBC_VERSION = '2.42'
KERNEL_VERSION = '6.1.150'
GCC_VERSION = "15.2.0"

TMP = Pathname.new('./tmp')

class BuildTarget
  def initialize(architecture)
    case architecture
    when /^r(isc)?v32$/
      @architecture = :rv32
    else
      raise "Unsupported architecture '#{architecture}'."
    end
  end

  def sysroot
    TMP + 'sysroot'
  end

  def rootfs
    TMP + 'rootfs'
  end

  def target
    case @architecture
    when :rv32
      'riscv32-unknown-linux-gnu'
    end
  end

  def build
    @build ||= gcc_verbose(ENV['CC']).lines
      .find { |line| line.start_with? 'Target: ' }
      .split(' ').last.strip
  end

  def configuration(prefix)
    case @architecture
    when :rv32
      ['arch=rv32imafdc', 'abi=ilp32d', 'tune=rocket', 'isa-spec=20191213'].map do |option|
        "-#{prefix}#{option}"
      end
    else
      []
    end
  end
end

def gcc_verbose(gcc_binary)
  read, write = IO.pipe
  system({'LANG' => 'C'}, gcc_binary, '--verbose', err: write)
  write.close
  output = read.read
  read.close
  output
end

def download_and_unarchive(url)
  puts Term::ANSIColor.green "Downloading #{url}."

  case File.extname url.path
  when '.bz2'
    archive_type = '-j'
    root_directory = File.basename url.path, '.tar.bz2'
  when '.xz'
    archive_type = '-J'
    root_directory = File.basename url.path, '.tar.xz'
  else
    raise "Unsupported archive type #{url.path}."
  end
  target = TMP + 'tools'
  Net::HTTP.start(url.host, url.port, use_ssl: url.scheme == 'https') do |http|
    request = Net::HTTP::Get.new url.request_uri

    http.request request do |response|
      case response
      when Net::HTTPRedirection
        download_and_unarchive URI.parse(response['location'])
      when Net::HTTPSuccess
        Open3.popen2 'tar', '-C', target.to_path, archive_type, '-xv' do |stdin, stdout, wait_thread|
          Thread.new do
            stdout.each { |line| puts line }
          end

          response.read_body do |chunk|
            stdin.write chunk
          end
          stdin.close

          wait_thread.value
        end
      else
        response.error!
      end
    end
  end
  target + root_directory
end

def configure_make_install(source_directory, configure_options, env, cwd)
  configure = source_directory.relative_path_from(cwd) + 'configure'
  system env, configure.to_path, *configure_options, chdir: cwd.to_path, exception: true
  system 'make', '-j', Etc.nprocessors.to_s, chdir: cwd.to_path, exception: true
  system env, 'make', 'install', chdir: cwd.to_path, exception: true
end

def major(version)
  version.split('.').first
end

def environment
  binary_suffix = ''
  output = gcc_verbose 'gcc'

  if output.start_with? 'Apple clang'
    binary_suffix = "-#{major(GCC_VERSION)}"
  end

  ENV['CC'] = "gcc#{binary_suffix}"
  ENV['CXX'] = "g++#{binary_suffix}"
end

# Build cross binutils.
def binutils(options)
  source_directory = download_and_unarchive(
    URI.parse("https://ftpmirror.gnu.org/gnu/binutils/binutils-#{BINUTILS_VERSION}.tar.xz"))

  cwd = source_directory.dirname + 'build-binutils'
  cwd.mkpath
  options.rootfs.mkpath
  options.sysroot.mkpath

  env = ENV.slice 'CC', 'CXX'
  configure_options = [
    "--prefix=#{options.rootfs.realpath}",
    "--target=#{options.target}",
    "--with-sysroot=#{options.sysroot.realpath}",
    '--disable-nls',
    '--enable-gprofng=no',
    '--disable-werror',
    '--enable-default-hash-style=gnu',
    '--disable-libquadmath'
  ]
  configure_make_install source_directory, configure_options, env, cwd
end

# Build stage 1 GCC.
def gcc1(options)
  source_directory = download_and_unarchive(
    URI.parse("https://gcc.gnu.org/pub/gcc/releases/gcc-#{GCC_VERSION}/gcc-#{GCC_VERSION}.tar.xz"))

  cwd = source_directory.dirname + 'build-gcc'
  cwd.mkpath
  options.rootfs.mkpath

  system 'contrib/download_prerequisites', chdir: source_directory.to_path, exception: true
  configure_options = options.configuration('-with-') + [
    "--prefix=#{options.rootfs.realpath}",
    "--with-sysroot=#{options.sysroot.realpath}",
    '--enable-languages=c,c++',
    '--disable-shared',
    '--disable-bootstrap',
    '--disable-multilib',
    '--disable-libmudflap',
    '--disable-libssp',
    '--disable-libquadmath',
    '--disable-libsanitizer',
    '--disable-threads',
    '--disable-libatomic',
    '--disable-libgomp',
    '--disable-libvtv',
    '--disable-libstdcxx',
    '--disable-nls',
    '--with-newlib',
    '--without-headers',
    "--target=#{options.target}",
    "--build=#{options.build}",
    "--host=#{options.build}"
  ]
  flags = '-O2 -fPIC'
  env = {
    'CC' => ENV['CC'],
    'CXX' => ENV['CXX'],
    'CFLAGS' => flags,
    'CXXFLAGS' => flags,
    'PATH' => "#{options.rootfs.realpath + 'bin'}:#{ENV['PATH']}"
  }
  configure_make_install source_directory, configure_options, env, cwd
end

# Copy glibc headers.
def headers(options)
  source_directory = download_and_unarchive(
    URI.parse("https://ftpmirror.gnu.org/gnu/glibc/glibc-#{GLIBC_VERSION}.tar.xz"))
  include_directory = TMP + 'tools/include'

  include_directory.mkpath
  FileUtils.cp (source_directory + 'elf/elf.h'), (include_directory + 'elf.h')
end

# Build linux kernel.
def kernel(options)
  cwd = download_and_unarchive(
    URI.parse("https://cdn.kernel.org/pub/linux/kernel/v#{major(KERNEL_VERSION)}.x/linux-#{KERNEL_VERSION}.tar.xz"))

  env = {
    'CROSS_COMPILE' => "#{options.target}-",
    'ARCH' => 'riscv',
    'PATH' => "#{options.rootfs.realpath + 'bin'}:#{ENV['PATH']}",
    'HOSTCFLAGS' => "-D_UUID_T -D__GETHOSTUUID_H -I#{TMP + 'tools/include'}"
  }
  system env, 'make', 'rv32_defconfig', chdir: cwd.to_path, exception: true
  # system env, 'make', '-j', Etc.nprocessors.to_s, chdir: cwd.to_path, exception: true
  system env, 'make', 'headers', chdir: cwd.to_path, exception: true

  user_directory = options.sysroot + 'usr'

  user_directory.mkpath
  FileUtils.cp_r (cwd + 'usr/include'), (user_directory + 'include')
end

# Build glibc.
def glibc(options)
  source_directory = TMP + "tools/glibc-#{GLIBC_VERSION}"
  configure_options = [
    '--prefix=/usr',
    "--host=#{options.target}",
    "--target=#{options.target}",
    "--build=#{options.build}",
    "--enable-kernel=#{KERNEL_VERSION}",
    "--with-headers=#{options.sysroot.realpath + 'usr/include'}",
    '--disable-nscd',
    '--disable-libquadmath',
    '--disable-libitm',
    '--disable-werror',
    'libc_cv_forced_unwind=yes'
  ]
  bin = options.rootfs.realpath + 'bin'
  env = {
    'PATH' => "#{bin}:#{ENV['PATH']}",
    'MAKE' => 'make', # Otherwise it uses gnumake which can be different and too old.
    'CC' => "#{options.target}-gcc",
    'CXX' => "#{options.target}-g++"
  }
  cwd = source_directory.dirname + 'build-glibc'
  cwd.mkpath

  configure = source_directory.relative_path_from(cwd) +'./configure'
  system env, configure.to_path, *configure_options, chdir: cwd.to_path, exception: true
  system env, 'make', '-j', Etc.nprocessors.to_s, chdir: cwd.to_path, exception: true
  system env, 'make', "install_root=#{options.sysroot.realpath}", 'install', chdir: cwd.to_path, exception: true
end

# Build stage 2 GCC.
def gcc2(options)
  source_directory = TMP + "tools/gcc-#{GCC_VERSION}"
  cwd = TMP + 'tools/build-gcc'

  FileUtils.rm_rf cwd
  cwd.mkpath

  configure_options = options.configuration('-with-') + [
    "--prefix=#{options.rootfs.realpath}",
    "--with-sysroot=#{options.sysroot.realpath}",
    '--enable-languages=c,c++,lto',
    '--enable-lto',
    '--enable-shared',
    '--disable-bootstrap',
    '--disable-multilib',
    '--enable-checking=release',
    '--disable-libssp',
    '--disable-libquadmath',
    '--enable-threads=posix',
    '--with-default-libstdcxx-abi=new',
    '--disable-nls',
    "--target=#{options.target}",
    "--build=#{options.build}",
    "--host=#{options.build}"
  ]
  flags = '-O2 -fPIC -I/opt/homebrew/opt/flex/include'
  env = {
    'CFLAGS' => flags,
    'CXXFLAGS' => flags,
    'PATH' => "#{options.rootfs.realpath + 'bin'}:#{ENV['PATH']}"
  }
  configure_make_install source_directory, configure_options, env, cwd
end

target = ARGV.fetch 0, 'riscv32'
options = BuildTarget.new target

(TMP + 'tools').mkpath
environment

binutils options
gcc1 options
headers options
kernel options
glibc options
gcc2 options