text: #!/usr/bin/env python
  # Copyright 2017 The Rust Project Developers. See the COPYRIGHT
  # file at the top-level directory of this distribution and at
  # http://rust-lang.org/COPYRIGHT.
  #
  # Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
  # http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
  # <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
  # option. This file may not be copied, modified, or distributed
  # except according to those terms.
  
  # ignore-tidy-linelength
  
  from __future__ import absolute_import, division, print_function
  import sys
  import os
  rust_dir = os.path.dirname(os.path.abspath(__file__))
  rust_dir = os.path.dirname(rust_dir)
  rust_dir = os.path.dirname(rust_dir)
  sys.path.append(os.path.join(rust_dir, "src", "bootstrap"))
  import bootstrap
  
  
  class Option(object):
      def __init__(self, name, rustbuild, desc, value):
          self.name = name
          self.rustbuild = rustbuild
          self.desc = desc
          self.value = value
  
  
  options = []
  
  
  def o(*args):
      options.append(Option(*args, value=False))
  
  
  def v(*args):
      options.append(Option(*args, value=True))
  
  
  o("debug", "rust.debug", "debug mode; disables optimization unless `--enable-optimize` given")
  o("docs", "build.docs", "build standard library documentation")
  o("compiler-docs", "build.compiler-docs", "build compiler documentation")
  o("optimize-tests", "rust.optimize-tests", "build tests with optimizations")
  o("test-miri", "rust.test-miri", "run miri's test suite")
  o("debuginfo-tests", "rust.debuginfo-tests", "build tests with debugger metadata")
  o("quiet-tests", "rust.quiet-tests", "enable quieter output when running tests")
  o("ccache", "llvm.ccache", "invoke gcc/clang via ccache to reuse object files between builds")
  o("sccache", None, "invoke gcc/clang via sccache to reuse object files between builds")
  o("local-rust", None, "use an installed rustc rather than downloading a snapshot")
  v("local-rust-root", None, "set prefix for local rust binary")
  o("local-rebuild", "build.local-rebuild", "assume local-rust matches the current version, for rebuilds; implies local-rust, and is implied if local-rust already matches the current version")
  o("llvm-static-stdcpp", "llvm.static-libstdcpp", "statically link to libstdc++ for LLVM")
  o("llvm-link-shared", "llvm.link-shared", "prefer shared linking to LLVM (llvm-config --link-shared)")
  o("rpath", "rust.rpath", "build rpaths into rustc itself")
  o("llvm-version-check", "llvm.version-check", "check if the LLVM version is supported, build anyway")
  o("codegen-tests", "rust.codegen-tests", "run the src/test/codegen tests")
  o("option-checking", None, "complain about unrecognized options in this configure script")
  o("ninja", "llvm.ninja", "build LLVM using the Ninja generator (for MSVC, requires building in the correct environment)")
  o("locked-deps", "build.locked-deps", "force Cargo.lock to be up to date")
  o("vendor", "build.vendor", "enable usage of vendored Rust crates")
  o("sanitizers", "build.sanitizers", "build the sanitizer runtimes (asan, lsan, msan, tsan)")
  o("dist-src", "rust.dist-src", "when building tarballs enables building a source tarball")
  o("cargo-openssl-static", "build.openssl-static", "static openssl in cargo")
  o("profiler", "build.profiler", "build the profiler runtime")
  o("emscripten", None, "compile the emscripten backend as well as LLVM")
  
  # Optimization and debugging options. These may be overridden by the release
  # channel, etc.
  o("optimize", "rust.optimize", "build optimized rust code")
  o("thinlto", "rust.thinlto", "build Rust with ThinLTO enabled")
  o("optimize-llvm", "llvm.optimize", "build optimized LLVM")
  o("llvm-assertions", "llvm.assertions", "build LLVM with assertions")
  o("debug-assertions", "rust.debug-assertions", "build with debugging assertions")
  o("llvm-release-debuginfo", "llvm.release-debuginfo", "build LLVM with debugger metadata")
  o("debuginfo", "rust.debuginfo", "build with debugger metadata")
  o("debuginfo-lines", "rust.debuginfo-lines", "build with line number debugger metadata")
  o("debuginfo-only-std", "rust.debuginfo-only-std", "build only libstd with debugging information")
  o("debug-jemalloc", "rust.debug-jemalloc", "build jemalloc with --enable-debug --enable-fill")
  v("save-toolstates", "rust.save-toolstates", "save build and test status of external tools into this file")
  
  v("prefix", "install.prefix", "set installation prefix")
  v("localstatedir", "install.localstatedir", "local state directory")
  v("datadir", "install.datadir", "install data")
  v("sysconfdir", "install.sysconfdir", "install system configuration files")
  v("infodir", "install.infodir", "install additional info")
  v("libdir", "install.libdir", "install libraries")
  v("mandir", "install.mandir", "install man pages in PATH")
  v("docdir", "install.docdir", "install documentation in PATH")
  v("bindir", "install.bindir", "install binaries")
  
  v("llvm-root", None, "set LLVM root")
  v("python", "build.python", "set path to python")
  v("jemalloc-root", None, "set directory where libjemalloc_pic.a is located")
  v("android-cross-path", "target.arm-linux-androideabi.android-ndk",
    "Android NDK standalone path (deprecated)")
  v("i686-linux-android-ndk", "target.i686-linux-android.android-ndk",
    "i686-linux-android NDK standalone path")
  v("arm-linux-androideabi-ndk", "target.arm-linux-androideabi.android-ndk",
    "arm-linux-androideabi NDK standalone path")
  v("armv7-linux-androideabi-ndk", "target.armv7-linux-androideabi.android-ndk",
    "armv7-linux-androideabi NDK standalone path")
  v("aarch64-linux-android-ndk", "target.aarch64-linux-android.android-ndk",
    "aarch64-linux-android NDK standalone path")
  v("x86_64-linux-android-ndk", "target.x86_64-linux-android.android-ndk",
    "x86_64-linux-android NDK standalone path")
  v("musl-root", "target.x86_64-unknown-linux-musl.musl-root",
    "MUSL root installation directory (deprecated)")
  v("musl-root-x86_64", "target.x86_64-unknown-linux-musl.musl-root",
    "x86_64-unknown-linux-musl install directory")
  v("musl-root-i586", "target.i586-unknown-linux-musl.musl-root",
    "i586-unknown-linux-musl install directory")
  v("musl-root-i686", "target.i686-unknown-linux-musl.musl-root",
    "i686-unknown-linux-musl install directory")
  v("musl-root-arm", "target.arm-unknown-linux-musleabi.musl-root",
    "arm-unknown-linux-musleabi install directory")
  v("musl-root-armhf", "target.arm-unknown-linux-musleabihf.musl-root",
    "arm-unknown-linux-musleabihf install directory")
  v("musl-root-armv7", "target.armv7-unknown-linux-musleabihf.musl-root",
    "armv7-unknown-linux-musleabihf install directory")
  v("musl-root-aarch64", "target.aarch64-unknown-linux-musl.musl-root",
    "aarch64-unknown-linux-musl install directory")
  v("musl-root-mips", "target.mips-unknown-linux-musl.musl-root",
    "mips-unknown-linux-musl install directory")
  v("musl-root-mipsel", "target.mipsel-unknown-linux-musl.musl-root",
    "mipsel-unknown-linux-musl install directory")
  v("qemu-armhf-rootfs", "target.arm-unknown-linux-gnueabihf.qemu-rootfs",
    "rootfs in qemu testing, you probably don't want to use this")
  v("qemu-aarch64-rootfs", "target.aarch64-unknown-linux-gnu.qemu-rootfs",
    "rootfs in qemu testing, you probably don't want to use this")
  v("experimental-targets", "llvm.experimental-targets",
    "experimental LLVM targets to build")
  v("release-channel", "rust.channel", "the name of the release channel to build")
  
  # Used on systems where "cc" is unavailable
  v("default-linker", "rust.default-linker", "the default linker")
  
  # Many of these are saved below during the "writing configuration" step
  # (others are conditionally saved).
  o("manage-submodules", "build.submodules", "let the build manage the git submodules")
  o("jemalloc", "rust.use-jemalloc", "build liballoc with jemalloc")
  o("full-bootstrap", "build.full-bootstrap", "build three compilers instead of two")
  o("extended", "build.extended", "build an extended rust tool set")
  
  v("tools", "build.tools", "List of extended tools will be installed")
  v("build", "build.build", "GNUs ./configure syntax LLVM build triple")
  v("host", None, "GNUs ./configure syntax LLVM host triples")
  v("target", None, "GNUs ./configure syntax LLVM target triples")
  
  v("set", None, "set arbitrary key/value pairs in TOML configuration")
  
  
  def p(msg):
      print("configure: " + msg)
  
  
  def err(msg):
      print("configure: error: " + msg)
      sys.exit(1)
  
  
  if '--help' in sys.argv or '-h' in sys.argv:
      print('Usage: ./configure [options]')
      print('')
      print('Options')
      for option in options:
          if 'android' in option.name:
              # no one needs to know about these obscure options
              continue
          if option.value:
              print('\t{:30} {}'.format('--{}=VAL'.format(option.name), option.desc))
          else:
              print('\t{:30} {}'.format('--enable-{}'.format(option.name), option.desc))
      print('')
      print('This configure script is a thin configuration shim over the true')
      print('configuration system, `config.toml`. You can explore the comments')
      print('in `config.toml.example` next to this configure script to see')
      print('more information about what each option is. Additionally you can')
      print('pass `--set` as an argument to set arbitrary key/value pairs')
      print('in the TOML configuration if desired')
      print('')
      print('Also note that all options which take `--enable` can similarly')
      print('be passed with `--disable-foo` to forcibly disable the option')
      sys.exit(0)
  
  # Parse all command line arguments into one of these three lists, handling
  # boolean and value-based options separately
  unknown_args = []
  need_value_args = []
  known_args = {}
  
  p("processing command line")
  i = 1
  while i < len(sys.argv):
      arg = sys.argv[i]
      i += 1
      if not arg.startswith('--'):
          unknown_args.append(arg)
          continue
  
      found = False
      for option in options:
          value = None
          if option.value:
              keyval = arg[2:].split('=', 1)
              key = keyval[0]
              if option.name != key:
                  continue
  
              if len(keyval) > 1:
                  value = keyval[1]
              elif i < len(sys.argv):
                  value = sys.argv[i]
                  i += 1
              else:
                  need_value_args.append(arg)
                  continue
          else:
              if arg[2:] == 'enable-' + option.name:
                  value = True
              elif arg[2:] == 'disable-' + option.name:
                  value = False
              else:
                  continue
  
          found = True
          if option.name not in known_args:
              known_args[option.name] = []
          known_args[option.name].append((option, value))
          break
  
      if not found:
          unknown_args.append(arg)
  p("")
  
  # Note: here and a few other places, we use [-1] to apply the *last* value
  # passed.  But if option-checking is enabled, then the known_args loop will
  # also assert that options are only passed once.
  option_checking = ('option-checking' not in known_args
                     or known_args['option-checking'][-1][1])
  if option_checking:
      if len(unknown_args) > 0:
          err("Option '" + unknown_args[0] + "' is not recognized")
      if len(need_value_args) > 0:
          err("Option '{0}' needs a value ({0}=val)".format(need_value_args[0]))
  
  # Parse all known arguments into a configuration structure that reflects the
  # TOML we're going to write out
  config = {}
  
  
  def build():
      if 'build' in known_args:
          return known_args['build'][-1][1]
      return bootstrap.default_build_triple()
  
  
  def set(key, value):
      s = "{:20} := {}".format(key, value)
      if len(s) < 70:
          p(s)
      else:
          p(s[:70] + " ...")
  
      arr = config
      parts = key.split('.')
      for i, part in enumerate(parts):
          if i == len(parts) - 1:
              arr[part] = value
          else:
              if part not in arr:
                  arr[part] = {}
              arr = arr[part]
  
  
  for key in known_args:
      # The `set` option is special and can be passed a bunch of times
      if key == 'set':
          for option, value in known_args[key]:
              keyval = value.split('=', 1)
              if len(keyval) == 1 or keyval[1] == "true":
                  value = True
              elif keyval[1] == "false":
                  value = False
              else:
                  value = keyval[1]
              set(keyval[0], value)
          continue
  
      # Ensure each option is only passed once
      arr = known_args[key]
      if option_checking and len(arr) > 1:
          err("Option '{}' provided more than once".format(key))
      option, value = arr[-1]
  
      # If we have a clear avenue to set our value in rustbuild, do so
      if option.rustbuild is not None:
          set(option.rustbuild, value)
          continue
  
      # Otherwise we're a "special" option and need some extra handling, so do
      # that here.
      if option.name == 'sccache':
          set('llvm.ccache', 'sccache')
      elif option.name == 'local-rust':
          for path in os.environ['PATH'].split(os.pathsep):
              if os.path.exists(path + '/rustc'):
                  set('build.rustc', path + '/rustc')
                  break
          for path in os.environ['PATH'].split(os.pathsep):
              if os.path.exists(path + '/cargo'):
                  set('build.cargo', path + '/cargo')
                  break
      elif option.name == 'local-rust-root':
          set('build.rustc', value + '/bin/rustc')
          set('build.cargo', value + '/bin/cargo')
      elif option.name == 'llvm-root':
          set('target.{}.llvm-config'.format(build()), value + '/bin/llvm-config')
      elif option.name == 'jemalloc-root':
          set('target.{}.jemalloc'.format(build()), value + '/libjemalloc_pic.a')
      elif option.name == 'host':
          set('build.host', value.split(','))
      elif option.name == 'target':
          set('build.target', value.split(','))
      elif option.name == 'emscripten':
          set('rust.codegen-backends', ['llvm', 'emscripten'])
      elif option.name == 'option-checking':
          # this was handled above
          pass
      else:
          raise RuntimeError("unhandled option {}".format(option.name))
  
  set('build.configure-args', sys.argv[1:])
  
  # "Parse" the `config.toml.example` file into the various sections, and we'll
  # use this as a template of a `config.toml` to write out which preserves
  # all the various comments and whatnot.
  #
  # Note that the `target` section is handled separately as we'll duplicate it
  # per configure dtarget, so there's a bit of special handling for that here.
  sections = {}
  cur_section = None
  sections[None] = []
  section_order = [None]
  targets = {}
  
  for line in open(rust_dir + '/config.toml.example').read().split("\n"):
      if line.startswith('['):
          cur_section = line[1:-1]
          if cur_section.startswith('target'):
              cur_section = 'target'
          elif '.' in cur_section:
              raise RuntimeError("don't know how to deal with section: {}".format(cur_section))
          sections[cur_section] = [line]
          section_order.append(cur_section)
      else:
          sections[cur_section].append(line)
  
  # Fill out the `targets` array by giving all configured targets a copy of the
  # `target` section we just loaded from the example config
  configured_targets = [build()]
  if 'build' in config:
      if 'host' in config['build']:
          configured_targets += config['build']['host']
      if 'target' in config['build']:
          configured_targets += config['build']['target']
  if 'target' in config:
      for target in config['target']:
          configured_targets.append(target)
  for target in configured_targets:
      targets[target] = sections['target'][:]
      targets[target][0] = targets[target][0].replace("x86_64-unknown-linux-gnu", target)
  
  
  # Here we walk through the constructed configuration we have from the parsed
  # command line arguments. We then apply each piece of configuration by
  # basically just doing a `sed` to change the various configuration line to what
  # we've got configure.
  def to_toml(value):
      if isinstance(value, bool):
          if value:
              return "true"
          else:
              return "false"
      elif isinstance(value, list):
          return '[' + ', '.join(map(to_toml, value)) + ']'
      elif isinstance(value, str):
          return "'" + value + "'"
      else:
          raise RuntimeError('no toml')
  
  
  def configure_section(lines, config):
      for key in config:
          value = config[key]
          found = False
          for i, line in enumerate(lines):
              if not line.startswith('#' + key + ' = '):
                  continue
              found = True
              lines[i] = "{} = {}".format(key, to_toml(value))
              break
          if not found:
              raise RuntimeError("failed to find config line for {}".format(key))
  
  
  for section_key in config:
      section_config = config[section_key]
      if section_key not in sections:
          raise RuntimeError("config key {} not in sections".format(section_key))
  
      if section_key == 'target':
          for target in section_config:
              configure_section(targets[target], section_config[target])
      else:
          configure_section(sections[section_key], section_config)
  
  # Now that we've built up our `config.toml`, write it all out in the same
  # order that we read it in.
  p("")
  p("writing `config.toml` in current directory")
  with open('config.toml', 'w') as f:
      for section in section_order:
          if section == 'target':
              for target in targets:
                  for line in targets[target]:
                      f.write(line + "\n")
          else:
              for line in sections[section]:
                  f.write(line + "\n")
  
  with open('Makefile', 'w') as f:
      contents = os.path.join(rust_dir, 'src', 'bootstrap', 'mk', 'Makefile.in')
      contents = open(contents).read()
      contents = contents.replace("$(CFG_SRC_DIR)", rust_dir + '/')
      contents = contents.replace("$(CFG_PYTHON)", sys.executable)
      f.write(contents)
  
  p("")
  p("run `python {}/x.py --help`".format(rust_dir))
  p("")
  