text: #!/usr/bin/env python
  #
  # Copyright 2001 Google Inc. All Rights Reserved.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  """Script that generates the build.ninja for ninja itself.
  
  Projects that use ninja themselves should either write a similar script
  or use a meta-build system that supports Ninja output."""
  
  from __future__ import print_function
  
  from optparse import OptionParser
  import os
  import pipes
  import string
  import subprocess
  import sys
  
  sourcedir = os.path.dirname(os.path.realpath(__file__))
  sys.path.insert(0, os.path.join(sourcedir, 'misc'))
  import ninja_syntax
  
  
  class Platform(object):
      """Represents a host/target platform and its specific build attributes."""
      def __init__(self, platform):
          self._platform = platform
          if self._platform is not None:
              return
          self._platform = sys.platform
          if self._platform.startswith('linux'):
              self._platform = 'linux'
          elif self._platform.startswith('freebsd'):
              self._platform = 'freebsd'
          elif self._platform.startswith('gnukfreebsd'):
              self._platform = 'freebsd'
          elif self._platform.startswith('openbsd'):
              self._platform = 'openbsd'
          elif self._platform.startswith('solaris') or self._platform == 'sunos5':
              self._platform = 'solaris'
          elif self._platform.startswith('mingw'):
              self._platform = 'mingw'
          elif self._platform.startswith('win'):
              self._platform = 'msvc'
          elif self._platform.startswith('bitrig'):
              self._platform = 'bitrig'
          elif self._platform.startswith('netbsd'):
              self._platform = 'netbsd'
          elif self._platform.startswith('aix'):
              self._platform = 'aix'
          elif self._platform.startswith('os400'):
              self._platform = 'os400'
          elif self._platform.startswith('dragonfly'):
              self._platform = 'dragonfly'
  
      @staticmethod
      def known_platforms():
        return ['linux', 'darwin', 'freebsd', 'openbsd', 'solaris', 'sunos5',
                'mingw', 'msvc', 'gnukfreebsd', 'bitrig', 'netbsd', 'aix',
                'dragonfly']
  
      def platform(self):
          return self._platform
  
      def is_linux(self):
          return self._platform == 'linux'
  
      def is_mingw(self):
          return self._platform == 'mingw'
  
      def is_msvc(self):
          return self._platform == 'msvc'
  
      def msvc_needs_fs(self):
          popen = subprocess.Popen(['cl', '/nologo', '/help'],
                                   stdout=subprocess.PIPE,
                                   stderr=subprocess.PIPE)
          out, err = popen.communicate()
          return b'/FS' in out
  
      def is_windows(self):
          return self.is_mingw() or self.is_msvc()
  
      def is_solaris(self):
          return self._platform == 'solaris'
  
      def is_aix(self):
          return self._platform == 'aix'
  
      def is_os400_pase(self):
          return self._platform == 'os400' or os.uname().sysname.startswith('OS400')
  
      def uses_usr_local(self):
          return self._platform in ('freebsd', 'openbsd', 'bitrig', 'dragonfly', 'netbsd')
  
      def supports_ppoll(self):
          return self._platform in ('freebsd', 'linux', 'openbsd', 'bitrig',
                                    'dragonfly')
  
      def supports_ninja_browse(self):
          return (not self.is_windows()
                  and not self.is_solaris()
                  and not self.is_aix())
  
      def can_rebuild_in_place(self):
          return not (self.is_windows() or self.is_aix())
  
  class Bootstrap:
      """API shim for ninja_syntax.Writer that instead runs the commands.
  
      Used to bootstrap Ninja from scratch.  In --bootstrap mode this
      class is used to execute all the commands to build an executable.
      It also proxies all calls to an underlying ninja_syntax.Writer, to
      behave like non-bootstrap mode.
      """
      def __init__(self, writer, verbose=False):
          self.writer = writer
          self.verbose = verbose
          # Map of variable name => expanded variable value.
          self.vars = {}
          # Map of rule name => dict of rule attributes.
          self.rules = {
              'phony': {}
          }
  
      def comment(self, text):
          return self.writer.comment(text)
  
      def newline(self):
          return self.writer.newline()
  
      def variable(self, key, val):
          # In bootstrap mode, we have no ninja process to catch /showIncludes
          # output.
          self.vars[key] = self._expand(val).replace('/showIncludes', '')
          return self.writer.variable(key, val)
  
      def rule(self, name, **kwargs):
          self.rules[name] = kwargs
          return self.writer.rule(name, **kwargs)
  
      def build(self, outputs, rule, inputs=None, **kwargs):
          ruleattr = self.rules[rule]
          cmd = ruleattr.get('command')
          if cmd is None:  # A phony rule, for example.
              return
  
          # Implement just enough of Ninja variable expansion etc. to
          # make the bootstrap build work.
          local_vars = {
              'in': self._expand_paths(inputs),
              'out': self._expand_paths(outputs)
          }
          for key, val in kwargs.get('variables', []):
              local_vars[key] = ' '.join(ninja_syntax.as_list(val))
  
          self._run_command(self._expand(cmd, local_vars))
  
          return self.writer.build(outputs, rule, inputs, **kwargs)
  
      def default(self, paths):
          return self.writer.default(paths)
  
      def _expand_paths(self, paths):
          """Expand $vars in an array of paths, e.g. from a 'build' block."""
          paths = ninja_syntax.as_list(paths)
          return ' '.join(map(self._shell_escape, (map(self._expand, paths))))
  
      def _expand(self, str, local_vars={}):
          """Expand $vars in a string."""
          return ninja_syntax.expand(str, self.vars, local_vars)
  
      def _shell_escape(self, path):
          """Quote paths containing spaces."""
          return '"%s"' % path if ' ' in path else path
  
      def _run_command(self, cmdline):
          """Run a subcommand, quietly.  Prints the full command on error."""
          try:
              if self.verbose:
                  print(cmdline)
              subprocess.check_call(cmdline, shell=True)
          except subprocess.CalledProcessError:
              print('when running: ', cmdline)
              raise
  
  
  parser = OptionParser()
  profilers = ['gmon', 'pprof']
  parser.add_option('--bootstrap', action='store_true',
                    help='bootstrap a ninja binary from nothing')
  parser.add_option('--verbose', action='store_true',
                    help='enable verbose build')
  parser.add_option('--platform',
                    help='target platform (' +
                         '/'.join(Platform.known_platforms()) + ')',
                    choices=Platform.known_platforms())
  parser.add_option('--host',
                    help='host platform (' +
                         '/'.join(Platform.known_platforms()) + ')',
                    choices=Platform.known_platforms())
  parser.add_option('--debug', action='store_true',
                    help='enable debugging extras',)
  parser.add_option('--profile', metavar='TYPE',
                    choices=profilers,
                    help='enable profiling (' + '/'.join(profilers) + ')',)
  parser.add_option('--with-gtest', metavar='PATH', help='ignored')
  parser.add_option('--with-python', metavar='EXE',
                    help='use EXE as the Python interpreter',
                    default=os.path.basename(sys.executable))
  parser.add_option('--force-pselect', action='store_true',
                    help='ppoll() is used by default where available, '
                         'but some platforms may need to use pselect instead',)
  (options, args) = parser.parse_args()
  if args:
      print('ERROR: extra unparsed command-line arguments:', args)
      sys.exit(1)
  
  platform = Platform(options.platform)
  if options.host:
      host = Platform(options.host)
  else:
      host = platform
  
  BUILD_FILENAME = 'build.ninja'
  ninja_writer = ninja_syntax.Writer(open(BUILD_FILENAME, 'w'))
  n = ninja_writer
  
  if options.bootstrap:
      # Make the build directory.
      try:
          os.mkdir('build')
      except OSError:
          pass
      # Wrap ninja_writer with the Bootstrapper, which also executes the
      # commands.
      print('bootstrapping ninja...')
      n = Bootstrap(n, verbose=options.verbose)
  
  n.comment('This file is used to build ninja itself.')
  n.comment('It is generated by ' + os.path.basename(__file__) + '.')
  n.newline()
  
  n.variable('ninja_required_version', '1.3')
  n.newline()
  
  n.comment('The arguments passed to configure.py, for rerunning it.')
  configure_args = sys.argv[1:]
  if '--bootstrap' in configure_args:
      configure_args.remove('--bootstrap')
  n.variable('configure_args', ' '.join(configure_args))
  env_keys = set(['CXX', 'AR', 'CFLAGS', 'CXXFLAGS', 'LDFLAGS'])
  configure_env = dict((k, os.environ[k]) for k in os.environ if k in env_keys)
  if configure_env:
      config_str = ' '.join([k + '=' + pipes.quote(configure_env[k])
                             for k in configure_env])
      n.variable('configure_env', config_str + '$ ')
  n.newline()
  
  CXX = configure_env.get('CXX', 'c++')
  objext = '.o'
  if platform.is_msvc():
      CXX = 'cl'
      objext = '.obj'
  
  def src(filename):
      return os.path.join('$root', 'src', filename)
  def built(filename):
      return os.path.join('$builddir', filename)
  def doc(filename):
      return os.path.join('$root', 'doc', filename)
  def cc(name, **kwargs):
      return n.build(built(name + objext), 'cxx', src(name + '.c'), **kwargs)
  def cxx(name, **kwargs):
      return n.build(built(name + objext), 'cxx', src(name + '.cc'), **kwargs)
  def binary(name):
      if platform.is_windows():
          exe = name + '.exe'
          n.build(name, 'phony', exe)
          return exe
      return name
  
  root = sourcedir
  if root == os.getcwd():
      # In the common case where we're building directly in the source
      # tree, simplify all the paths to just be cwd-relative.
      root = '.'
  n.variable('root', root)
  n.variable('builddir', 'build')
  n.variable('cxx', CXX)
  if platform.is_msvc():
      n.variable('ar', 'link')
  else:
      n.variable('ar', configure_env.get('AR', 'ar'))
  
  # Note that build settings are separately specified in CMakeLists.txt and
  # these lists should be kept in sync.
  if platform.is_msvc():
      cflags = ['/showIncludes',
                '/nologo',  # Don't print startup banner.
                '/Zi',  # Create pdb with debug info.
                '/W4',  # Highest warning level.
                '/WX',  # Warnings as errors.
                '/wd4530', '/wd4100', '/wd4706', '/wd4244',
                '/wd4512', '/wd4800', '/wd4702', '/wd4819',
                # Disable warnings about constant conditional expressions.
                '/wd4127',
                # Disable warnings about passing "this" during initialization.
                '/wd4355',
                # Disable warnings about ignored typedef in DbgHelp.h
                '/wd4091',
                '/GR-',  # Disable RTTI.
                '/Zc:__cplusplus',
                # Disable size_t -> int truncation warning.
                # We never have strings or arrays larger than 2**31.
                '/wd4267',
                '/DNOMINMAX', '/D_CRT_SECURE_NO_WARNINGS',
                '/D_HAS_EXCEPTIONS=0',
                '/DNINJA_PYTHON="%s"' % options.with_python]
      if platform.msvc_needs_fs():
          cflags.append('/FS')
      ldflags = ['/DEBUG', '/libpath:$builddir']
      if not options.debug:
          cflags += ['/Ox', '/DNDEBUG', '/GL']
          ldflags += ['/LTCG', '/OPT:REF', '/OPT:ICF']
  else:
      cflags = ['-g', '-Wall', '-Wextra',
                '-Wno-deprecated',
                '-Wno-missing-field-initializers',
                '-Wno-unused-parameter',
                '-fno-rtti',
                '-fno-exceptions',
                '-std=c++11',
                '-fvisibility=hidden', '-pipe',
                '-DNINJA_PYTHON="%s"' % options.with_python]
      if options.debug:
          cflags += ['-D_GLIBCXX_DEBUG', '-D_GLIBCXX_DEBUG_PEDANTIC']
          cflags.remove('-fno-rtti')  # Needed for above pedanticness.
      else:
          cflags += ['-O2', '-DNDEBUG']
      try:
          proc = subprocess.Popen(
              [CXX, '-fdiagnostics-color', '-c', '-x', 'c++', '/dev/null',
               '-o', '/dev/null'],
              stdout=open(os.devnull, 'wb'), stderr=subprocess.STDOUT)
          if proc.wait() == 0:
              cflags += ['-fdiagnostics-color']
      except:
          pass
      if platform.is_mingw():
          cflags += ['-D_WIN32_WINNT=0x0601', '-D__USE_MINGW_ANSI_STDIO=1']
      ldflags = ['-L$builddir']
      if platform.uses_usr_local():
          cflags.append('-I/usr/local/include')
          ldflags.append('-L/usr/local/lib')
      if platform.is_aix():
          # printf formats for int64_t, uint64_t; large file support
          cflags.append('-D__STDC_FORMAT_MACROS')
          cflags.append('-D_LARGE_FILES')
  
  
  libs = []
  
  if platform.is_mingw():
      cflags.remove('-fvisibility=hidden');
      ldflags.append('-static')
  elif platform.is_solaris():
      cflags.remove('-fvisibility=hidden')
  elif platform.is_aix():
      cflags.remove('-fvisibility=hidden')
  elif platform.is_msvc():
      pass
  else:
      if options.profile == 'gmon':
          cflags.append('-pg')
          ldflags.append('-pg')
      elif options.profile == 'pprof':
          cflags.append('-fno-omit-frame-pointer')
          libs.extend(['-Wl,--no-as-needed', '-lprofiler'])
  
  if platform.supports_ppoll() and not options.force_pselect:
      cflags.append('-DUSE_PPOLL')
  if platform.supports_ninja_browse():
      cflags.append('-DNINJA_HAVE_BROWSE')
  
  # Search for generated headers relative to build dir.
  cflags.append('-I.')
  
  def shell_escape(str):
      """Escape str such that it's interpreted as a single argument by
      the shell."""
  
      # This isn't complete, but it's just enough to make NINJA_PYTHON work.
      if platform.is_windows():
        return str
      if '"' in str:
          return "'%s'" % str.replace("'", "\\'")
      return str
  
  if 'CFLAGS' in configure_env:
      cflags.append(configure_env['CFLAGS'])
      ldflags.append(configure_env['CFLAGS'])
  if 'CXXFLAGS' in configure_env:
      cflags.append(configure_env['CXXFLAGS'])
      ldflags.append(configure_env['CXXFLAGS'])
  n.variable('cflags', ' '.join(shell_escape(flag) for flag in cflags))
  if 'LDFLAGS' in configure_env:
      ldflags.append(configure_env['LDFLAGS'])
  n.variable('ldflags', ' '.join(shell_escape(flag) for flag in ldflags))
  n.newline()
  
  if platform.is_msvc():
      n.rule('cxx',
          command='$cxx $cflags -c $in /Fo$out /Fd' + built('$pdb'),
          description='CXX $out',
          deps='msvc'  # /showIncludes is included in $cflags.
      )
  else:
      n.rule('cxx',
          command='$cxx -MMD -MT $out -MF $out.d $cflags -c $in -o $out',
          depfile='$out.d',
          deps='gcc',
          description='CXX $out')
  n.newline()
  
  if host.is_msvc():
      n.rule('ar',
             command='lib /nologo /ltcg /out:$out $in',
             description='LIB $out')
  elif host.is_mingw():
      n.rule('ar',
             command='$ar crs $out $in',
             description='AR $out')
  else:
      n.rule('ar',
             command='rm -f $out && $ar crs $out $in',
             description='AR $out')
  n.newline()
  
  if platform.is_msvc():
      n.rule('link',
          command='$cxx $in $libs /nologo /link $ldflags /out:$out',
          description='LINK $out')
  else:
      n.rule('link',
          command='$cxx $ldflags -o $out $in $libs',
          description='LINK $out')
  n.newline()
  
  objs = []
  
  if platform.supports_ninja_browse():
      n.comment('browse_py.h is used to inline browse.py.')
      n.rule('inline',
             command='"%s"' % src('inline.sh') + ' $varname < $in > $out',
             description='INLINE $out')
      n.build(built('browse_py.h'), 'inline', src('browse.py'),
              implicit=src('inline.sh'),
              variables=[('varname', 'kBrowsePy')])
      n.newline()
  
      objs += cxx('browse', order_only=built('browse_py.h'))
      n.newline()
  
  n.comment('the depfile parser and ninja lexers are generated using re2c.')
  def has_re2c():
      try:
          proc = subprocess.Popen(['re2c', '-V'], stdout=subprocess.PIPE)
          return int(proc.communicate()[0], 10) >= 1103
      except OSError:
          return False
  if has_re2c():
      n.rule('re2c',
             command='re2c -b -i --no-generation-date --no-version -o $out $in',
             description='RE2C $out')
      # Generate the .cc files in the source directory so we can check them in.
      n.build(src('depfile_parser.cc'), 're2c', src('depfile_parser.in.cc'))
      n.build(src('lexer.cc'), 're2c', src('lexer.in.cc'))
  else:
      print("warning: A compatible version of re2c (>= 0.11.3) was not found; "
             "changes to src/*.in.cc will not affect your build.")
  n.newline()
  
  n.comment('Core source files all build into ninja library.')
  cxxvariables = []
  if platform.is_msvc():
      cxxvariables = [('pdb', 'ninja.pdb')]
  for name in ['build',
               'build_log',
               'clean',
               'clparser',
               'debug_flags',
               'depfile_parser',
               'deps_log',
               'disk_interface',
               'dyndep',
               'dyndep_parser',
               'edit_distance',
               'eval_env',
               'graph',
               'graphviz',
               'json',
               'lexer',
               'line_printer',
               'manifest_parser',
               'metrics',
               'missing_deps',
               'parser',
               'state',
               'status',
               'string_piece_util',
               'util',
               'version']:
      objs += cxx(name, variables=cxxvariables)
  if platform.is_windows():
      for name in ['subprocess-win32',
                   'includes_normalize-win32',
                   'msvc_helper-win32',
                   'msvc_helper_main-win32']:
          objs += cxx(name, variables=cxxvariables)
      if platform.is_msvc():
          objs += cxx('minidump-win32', variables=cxxvariables)
      objs += cc('getopt')
  else:
      objs += cxx('subprocess-posix')
  if platform.is_aix():
      objs += cc('getopt')
  if platform.is_msvc():
      ninja_lib = n.build(built('ninja.lib'), 'ar', objs)
  else:
      ninja_lib = n.build(built('libninja.a'), 'ar', objs)
  n.newline()
  
  if platform.is_msvc():
      libs.append('ninja.lib')
  else:
      libs.append('-lninja')
  
  if platform.is_aix() and not platform.is_os400_pase():
      libs.append('-lperfstat')
  
  all_targets = []
  
  n.comment('Main executable is library plus main() function.')
  objs = cxx('ninja', variables=cxxvariables)
  ninja = n.build(binary('ninja'), 'link', objs, implicit=ninja_lib,
                  variables=[('libs', libs)])
  n.newline()
  all_targets += ninja
  
  if options.bootstrap:
      # We've built the ninja binary.  Don't run any more commands
      # through the bootstrap executor, but continue writing the
      # build.ninja file.
      n = ninja_writer
  
  n.comment('Tests all build into ninja_test executable.')
  
  objs = []
  if platform.is_msvc():
      cxxvariables = [('pdb', 'ninja_test.pdb')]
  
  for name in ['build_log_test',
               'build_test',
               'clean_test',
               'clparser_test',
               'depfile_parser_test',
               'deps_log_test',
               'dyndep_parser_test',
               'disk_interface_test',
               'edit_distance_test',
               'graph_test',
               'json_test',
               'lexer_test',
               'manifest_parser_test',
               'missing_deps_test',
               'ninja_test',
               'state_test',
               'status_test',
               'string_piece_util_test',
               'subprocess_test',
               'test',
               'util_test']:
      objs += cxx(name, variables=cxxvariables)
  if platform.is_windows():
      for name in ['includes_normalize_test', 'msvc_helper_test']:
          objs += cxx(name, variables=cxxvariables)
  
  ninja_test = n.build(binary('ninja_test'), 'link', objs, implicit=ninja_lib,
                       variables=[('libs', libs)])
  n.newline()
  all_targets += ninja_test
  
  
  n.comment('Ancillary executables.')
  
  if platform.is_aix() and '-maix64' not in ldflags:
      # Both hash_collision_bench and manifest_parser_perftest require more
      # memory than will fit in the standard 32-bit AIX shared stack/heap (256M)
      libs.append('-Wl,-bmaxdata:0x80000000')
  
  for name in ['build_log_perftest',
               'canon_perftest',
               'depfile_parser_perftest',
               'hash_collision_bench',
               'manifest_parser_perftest',
               'clparser_perftest']:
    if platform.is_msvc():
      cxxvariables = [('pdb', name + '.pdb')]
    objs = cxx(name, variables=cxxvariables)
    all_targets += n.build(binary(name), 'link', objs,
                           implicit=ninja_lib, variables=[('libs', libs)])
  
  n.newline()
  
  n.comment('Generate a graph using the "graph" tool.')
  n.rule('gendot',
         command='./ninja -t graph all > $out')
  n.rule('gengraph',
         command='dot -Tpng $in > $out')
  dot = n.build(built('graph.dot'), 'gendot', ['ninja', 'build.ninja'])
  n.build('graph.png', 'gengraph', dot)
  n.newline()
  
  n.comment('Generate the manual using asciidoc.')
  n.rule('asciidoc',
         command='asciidoc -b docbook -d book -o $out $in',
         description='ASCIIDOC $out')
  n.rule('xsltproc',
         command='xsltproc --nonet doc/docbook.xsl $in > $out',
         description='XSLTPROC $out')
  docbookxml = n.build(built('manual.xml'), 'asciidoc', doc('manual.asciidoc'))
  manual = n.build(doc('manual.html'), 'xsltproc', docbookxml,
                   implicit=[doc('style.css'), doc('docbook.xsl')])
  n.build('manual', 'phony',
          order_only=manual)
  n.newline()
  
  n.rule('dblatex',
         command='dblatex -q -o $out -p doc/dblatex.xsl $in',
         description='DBLATEX $out')
  n.build(doc('manual.pdf'), 'dblatex', docbookxml,
          implicit=[doc('dblatex.xsl')])
  
  n.comment('Generate Doxygen.')
  n.rule('doxygen',
         command='doxygen $in',
         description='DOXYGEN $in')
  n.variable('doxygen_mainpage_generator',
             src('gen_doxygen_mainpage.sh'))
  n.rule('doxygen_mainpage',
         command='$doxygen_mainpage_generator $in > $out',
         description='DOXYGEN_MAINPAGE $out')
  mainpage = n.build(built('doxygen_mainpage'), 'doxygen_mainpage',
                     ['README.md', 'COPYING'],
                     implicit=['$doxygen_mainpage_generator'])
  n.build('doxygen', 'doxygen', doc('doxygen.config'),
          implicit=mainpage)
  n.newline()
  
  if not host.is_mingw():
      n.comment('Regenerate build files if build script changes.')
      n.rule('configure',
             command='${configure_env}%s $root/configure.py $configure_args' %
                 options.with_python,
             generator=True)
      n.build('build.ninja', 'configure',
              implicit=['$root/configure.py',
                        os.path.normpath('$root/misc/ninja_syntax.py')])
      n.newline()
  
  n.default(ninja)
  n.newline()
  
  if host.is_linux():
      n.comment('Packaging')
      n.rule('rpmbuild',
             command="misc/packaging/rpmbuild.sh",
             description='Building rpms..')
      n.build('rpm', 'rpmbuild')
      n.newline()
  
  n.build('all', 'phony', all_targets)
  
  n.close()
  print('wrote %s.' % BUILD_FILENAME)
  
  if options.bootstrap:
      print('bootstrap complete.  rebuilding...')
  
      rebuild_args = []
  
      if platform.can_rebuild_in_place():
          rebuild_args.append('./ninja')
      else:
          if platform.is_windows():
              bootstrap_exe = 'ninja.bootstrap.exe'
              final_exe = 'ninja.exe'
          else:
              bootstrap_exe = './ninja.bootstrap'
              final_exe = './ninja'
  
          if os.path.exists(bootstrap_exe):
              os.unlink(bootstrap_exe)
          os.rename(final_exe, bootstrap_exe)
  
          rebuild_args.append(bootstrap_exe)
  
      if options.verbose:
          rebuild_args.append('-v')
  
      subprocess.check_call(rebuild_args)
  