setup: don't fail when Python doesn't have the cygwinccompiler package

Some Python installations like the ones available from the optware
project
for the Synology DiskStation NASes don't have that package, which means
running the setup script will crash and exit right away. Instead, we now
just use an empty/fake class for the HackedMingw32CCompiler, which we
likely won't use anyway.

setup.py

@@ -1,637 +1,646 b''
 #
 # This is the mercurial setup script.
 #
 # 'python setup.py install', or
 # 'python setup.py --help' for more options
 
 import sys, platform
 if getattr(sys, 'version_info', (0, 0, 0)) < (2, 4, 0, 'final'):
     raise SystemExit("Mercurial requires Python 2.4 or later.")
 
 if sys.version_info[0] >= 3:
     def b(s):
         '''A helper function to emulate 2.6+ bytes literals using string
         literals.'''
         return s.encode('latin1')
     printf = eval('print')
     libdir_escape = 'unicode_escape'
 else:
     libdir_escape = 'string_escape'
     def b(s):
         '''A helper function to emulate 2.6+ bytes literals using string
         literals.'''
         return s
     def printf(*args, **kwargs):
         f = kwargs.get('file', sys.stdout)
         end = kwargs.get('end', '\n')
         f.write(b(' ').join(args) + end)
 
 # Solaris Python packaging brain damage
 try:
     import hashlib
     sha = hashlib.sha1()
 except ImportError:
     try:
         import sha
         sha.sha # silence unused import warning
     except ImportError:
         raise SystemExit(
             "Couldn't import standard hashlib (incomplete Python install).")
 
 try:
     import zlib
     zlib.compressobj # silence unused import warning
 except ImportError:
     raise SystemExit(
         "Couldn't import standard zlib (incomplete Python install).")
 
 # The base IronPython distribution (as of 2.7.1) doesn't support bz2
 isironpython = False
 try:
     isironpython = (platform.python_implementation()
                     .lower().find("ironpython") != -1)
 except AttributeError:
     pass
 
 if isironpython:
     sys.stderr.write("warning: IronPython detected (no bz2 support)\n")
 else:
     try:
         import bz2
         bz2.BZ2Compressor # silence unused import warning
     except ImportError:
         raise SystemExit(
             "Couldn't import standard bz2 (incomplete Python install).")
 
 import os, stat, subprocess, time
 import re
 import shutil
 import tempfile
 from distutils import log
 from distutils.core import setup, Command, Extension
 from distutils.dist import Distribution
 from distutils.command.build import build
 from distutils.command.build_ext import build_ext
 from distutils.command.build_py import build_py
 from distutils.command.install_lib import install_lib
 from distutils.command.install_scripts import install_scripts
 from distutils.spawn import spawn, find_executable
-from distutils import cygwinccompiler, file_util
+from distutils import file_util
 from distutils.errors import CCompilerError, DistutilsExecError
 from distutils.sysconfig import get_python_inc, get_config_var
 from distutils.version import StrictVersion
 
 convert2to3 = '--c2to3' in sys.argv
 if convert2to3:
     try:
         from distutils.command.build_py import build_py_2to3 as build_py
         from lib2to3.refactor import get_fixers_from_package as getfixers
     except ImportError:
         if sys.version_info[0] < 3:
             raise SystemExit("--c2to3 is only compatible with python3.")
         raise
     sys.path.append('contrib')
 elif sys.version_info[0] >= 3:
     raise SystemExit("setup.py with python3 needs --c2to3 (experimental)")
 
 scripts = ['hg']
 if os.name == 'nt':
     scripts.append('contrib/win32/hg.bat')
 
 # simplified version of distutils.ccompiler.CCompiler.has_function
 # that actually removes its temporary files.
 def hasfunction(cc, funcname):
     tmpdir = tempfile.mkdtemp(prefix='hg-install-')
     devnull = oldstderr = None
     try:
         try:
             fname = os.path.join(tmpdir, 'funcname.c')
             f = open(fname, 'w')
             f.write('int main(void) {\n')
             f.write('    %s();\n' % funcname)
             f.write('}\n')
             f.close()
             # Redirect stderr to /dev/null to hide any error messages
             # from the compiler.
             # This will have to be changed if we ever have to check
             # for a function on Windows.
             devnull = open('/dev/null', 'w')
             oldstderr = os.dup(sys.stderr.fileno())
             os.dup2(devnull.fileno(), sys.stderr.fileno())
             objects = cc.compile([fname], output_dir=tmpdir)
             cc.link_executable(objects, os.path.join(tmpdir, "a.out"))
         except Exception:
             return False
         return True
     finally:
         if oldstderr is not None:
             os.dup2(oldstderr, sys.stderr.fileno())
         if devnull is not None:
             devnull.close()
         shutil.rmtree(tmpdir)
 
 # py2exe needs to be installed to work
 try:
     import py2exe
     py2exe.Distribution # silence unused import warning
     py2exeloaded = True
     # import py2exe's patched Distribution class
     from distutils.core import Distribution
 except ImportError:
     py2exeloaded = False
 
 def runcmd(cmd, env):
     if (sys.platform == 'plan9'
        and (sys.version_info[0] == 2 and sys.version_info[1] < 7)):
         # subprocess kludge to work around issues in half-baked Python
         # ports, notably bichued/python:
         _, out, err = os.popen3(cmd)
         return str(out), str(err)
     else:
         p = subprocess.Popen(cmd, stdout=subprocess.PIPE,
                              stderr=subprocess.PIPE, env=env)
         out, err = p.communicate()
         return out, err
 
 def runhg(cmd, env):
     out, err = runcmd(cmd, env)
     # If root is executing setup.py, but the repository is owned by
     # another user (as in "sudo python setup.py install") we will get
     # trust warnings since the .hg/hgrc file is untrusted. That is
     # fine, we don't want to load it anyway.  Python may warn about
     # a missing __init__.py in mercurial/locale, we also ignore that.
     err = [e for e in err.splitlines()
            if not e.startswith(b('not trusting file')) \
               and not e.startswith(b('warning: Not importing')) \
               and not e.startswith(b('obsolete feature not enabled'))]
     if err:
         printf("stderr from '%s':" % (' '.join(cmd)), file=sys.stderr)
         printf(b('\n').join([b('  ') + e for e in err]), file=sys.stderr)
         return ''
     return out
 
 version = ''
 
 # Execute hg out of this directory with a custom environment which
 # includes the pure Python modules in mercurial/pure. We also take
 # care to not use any hgrc files and do no localization.
 pypath = ['mercurial', os.path.join('mercurial', 'pure')]
 env = {'PYTHONPATH': os.pathsep.join(pypath),
        'HGRCPATH': '',
        'LANGUAGE': 'C'}
 if 'LD_LIBRARY_PATH' in os.environ:
     env['LD_LIBRARY_PATH'] = os.environ['LD_LIBRARY_PATH']
 if 'SystemRoot' in os.environ:
     # Copy SystemRoot into the custom environment for Python 2.6
     # under Windows. Otherwise, the subprocess will fail with
     # error 0xc0150004. See: http://bugs.python.org/issue3440
     env['SystemRoot'] = os.environ['SystemRoot']
 
 if os.path.isdir('.hg'):
     cmd = [sys.executable, 'hg', 'log', '-r', '.', '--template', '{tags}\n']
     numerictags = [t for t in runhg(cmd, env).split() if t[0].isdigit()]
     hgid = runhg([sys.executable, 'hg', 'id', '-i'], env).strip()
     if numerictags: # tag(s) found
         version = numerictags[-1]
         if hgid.endswith('+'): # propagate the dirty status to the tag
             version += '+'
     else: # no tag found
         ltagcmd = [sys.executable, 'hg', 'parents', '--template',
                    '{latesttag}']
         ltag = runhg(ltagcmd, env)
         changessincecmd = [sys.executable, 'hg', 'log', '-T', 'x\n', '-r',
                            "only(.,'%s')" % ltag]
         changessince = len(runhg(changessincecmd, env).splitlines())
         version = '%s+%s-%s' % (ltag, changessince, hgid)
     if version.endswith('+'):
         version += time.strftime('%Y%m%d')
 elif os.path.exists('.hg_archival.txt'):
     kw = dict([[t.strip() for t in l.split(':', 1)]
                for l in open('.hg_archival.txt')])
     if 'tag' in kw:
         version =  kw['tag']
     elif 'latesttag' in kw:
         if 'changessincelatesttag' in kw:
             version = '%(latesttag)s+%(changessincelatesttag)s-%(node).12s' % kw
         else:
             version = '%(latesttag)s+%(latesttagdistance)s-%(node).12s' % kw
     else:
         version = kw.get('node', '')[:12]
 
 if version:
     f = open("mercurial/__version__.py", "w")
     f.write('# this file is autogenerated by setup.py\n')
     f.write('version = "%s"\n' % version)
     f.close()
 
 
 try:
     from mercurial import __version__
     version = __version__.version
 except ImportError:
     version = 'unknown'
 
 class hgbuild(build):
     # Insert hgbuildmo first so that files in mercurial/locale/ are found
     # when build_py is run next.
     sub_commands = [('build_mo', None),
 
     # We also need build_ext before build_py. Otherwise, when 2to3 is
     # called (in build_py), it will not find osutil & friends,
     # thinking that those modules are global and, consequently, making
     # a mess, now that all module imports are global.
 
                     ('build_ext', build.has_ext_modules),
                    ] + build.sub_commands
 
 class hgbuildmo(build):
 
     description = "build translations (.mo files)"
 
     def run(self):
         if not find_executable('msgfmt'):
             self.warn("could not find msgfmt executable, no translations "
                      "will be built")
             return
 
         podir = 'i18n'
         if not os.path.isdir(podir):
             self.warn("could not find %s/ directory" % podir)
             return
 
         join = os.path.join
         for po in os.listdir(podir):
             if not po.endswith('.po'):
                 continue
             pofile = join(podir, po)
             modir = join('locale', po[:-3], 'LC_MESSAGES')
             mofile = join(modir, 'hg.mo')
             mobuildfile = join('mercurial', mofile)
             cmd = ['msgfmt', '-v', '-o', mobuildfile, pofile]
             if sys.platform != 'sunos5':
                 # msgfmt on Solaris does not know about -c
                 cmd.append('-c')
             self.mkpath(join('mercurial', modir))
             self.make_file([pofile], mobuildfile, spawn, (cmd,))
 
 
 class hgdist(Distribution):
     pure = 0
 
     global_options = Distribution.global_options + \
                      [('pure', None, "use pure (slow) Python "
                         "code instead of C extensions"),
                       ('c2to3', None, "(experimental!) convert "
                         "code with 2to3"),
                      ]
 
     def has_ext_modules(self):
         # self.ext_modules is emptied in hgbuildpy.finalize_options which is
         # too late for some cases
         return not self.pure and Distribution.has_ext_modules(self)
 
 class hgbuildext(build_ext):
 
     def build_extension(self, ext):
         try:
             build_ext.build_extension(self, ext)
         except CCompilerError:
             if not getattr(ext, 'optional', False):
                 raise
             log.warn("Failed to build optional extension '%s' (skipping)",
                      ext.name)
 
 class hgbuildpy(build_py):
     if convert2to3:
         fixer_names = sorted(set(getfixers("lib2to3.fixes") +
                                  getfixers("hgfixes")))
 
     def finalize_options(self):
         build_py.finalize_options(self)
 
         if self.distribution.pure:
             if self.py_modules is None:
                 self.py_modules = []
             for ext in self.distribution.ext_modules:
                 if ext.name.startswith("mercurial."):
                     self.py_modules.append("mercurial.pure.%s" % ext.name[10:])
             self.distribution.ext_modules = []
         else:
             h = os.path.join(get_python_inc(), 'Python.h')
             if not os.path.exists(h):
                 raise SystemExit('Python headers are required to build '
                                  'Mercurial but weren\'t found in %s' % h)
 
     def find_modules(self):
         modules = build_py.find_modules(self)
         for module in modules:
             if module[0] == "mercurial.pure":
                 if module[1] != "__init__":
                     yield ("mercurial", module[1], module[2])
             else:
                 yield module
 
 class buildhgextindex(Command):
     description = 'generate prebuilt index of hgext (for frozen package)'
     user_options = []
     _indexfilename = 'hgext/__index__.py'
 
     def initialize_options(self):
         pass
 
     def finalize_options(self):
         pass
 
     def run(self):
         if os.path.exists(self._indexfilename):
             f = open(self._indexfilename, 'w')
             f.write('# empty\n')
             f.close()
 
         # here no extension enabled, disabled() lists up everything
         code = ('import pprint; from mercurial import extensions; '
                 'pprint.pprint(extensions.disabled())')
         out, err = runcmd([sys.executable, '-c', code], env)
         if err:
             raise DistutilsExecError(err)
 
         f = open(self._indexfilename, 'w')
         f.write('# this file is autogenerated by setup.py\n')
         f.write('docs = ')
         f.write(out)
         f.close()
 
 class buildhgexe(build_ext):
     description = 'compile hg.exe from mercurial/exewrapper.c'
 
     def build_extensions(self):
         if os.name != 'nt':
             return
         if isinstance(self.compiler, HackedMingw32CCompiler):
             self.compiler.compiler_so = self.compiler.compiler # no -mdll
             self.compiler.dll_libraries = [] # no -lmsrvc90
         hv = sys.hexversion
         pythonlib = 'python%d%d' % (hv >> 24, (hv >> 16) & 0xff)
         f = open('mercurial/hgpythonlib.h', 'wb')
         f.write('/* this file is autogenerated by setup.py */\n')
         f.write('#define HGPYTHONLIB "%s"\n' % pythonlib)
         f.close()
         objects = self.compiler.compile(['mercurial/exewrapper.c'],
                                          output_dir=self.build_temp)
         dir = os.path.dirname(self.get_ext_fullpath('dummy'))
         target = os.path.join(dir, 'hg')
         self.compiler.link_executable(objects, target,
                                       libraries=[],
                                       output_dir=self.build_temp)
 
 class hginstalllib(install_lib):
     '''
     This is a specialization of install_lib that replaces the copy_file used
     there so that it supports setting the mode of files after copying them,
     instead of just preserving the mode that the files originally had.  If your
     system has a umask of something like 027, preserving the permissions when
     copying will lead to a broken install.
 
     Note that just passing keep_permissions=False to copy_file would be
     insufficient, as it might still be applying a umask.
     '''
 
     def run(self):
         realcopyfile = file_util.copy_file
         def copyfileandsetmode(*args, **kwargs):
             src, dst = args[0], args[1]
             dst, copied = realcopyfile(*args, **kwargs)
             if copied:
                 st = os.stat(src)
                 # Persist executable bit (apply it to group and other if user
                 # has it)
                 if st[stat.ST_MODE] & stat.S_IXUSR:
                     setmode = 0755
                 else:
                     setmode = 0644
                 os.chmod(dst, (stat.S_IMODE(st[stat.ST_MODE]) & ~0777) |
                          setmode)
         file_util.copy_file = copyfileandsetmode
         try:
             install_lib.run(self)
         finally:
             file_util.copy_file = realcopyfile
 
 class hginstallscripts(install_scripts):
     '''
     This is a specialization of install_scripts that replaces the @LIBDIR@ with
     the configured directory for modules. If possible, the path is made relative
     to the directory for scripts.
     '''
 
     def initialize_options(self):
         install_scripts.initialize_options(self)
 
         self.install_lib = None
 
     def finalize_options(self):
         install_scripts.finalize_options(self)
         self.set_undefined_options('install',
                                    ('install_lib', 'install_lib'))
 
     def run(self):
         install_scripts.run(self)
 
         if (os.path.splitdrive(self.install_dir)[0] !=
             os.path.splitdrive(self.install_lib)[0]):
             # can't make relative paths from one drive to another, so use an
             # absolute path instead
             libdir = self.install_lib
         else:
             common = os.path.commonprefix((self.install_dir, self.install_lib))
             rest = self.install_dir[len(common):]
             uplevel = len([n for n in os.path.split(rest) if n])
 
             libdir =  uplevel * ('..' + os.sep) + self.install_lib[len(common):]
 
         for outfile in self.outfiles:
             fp = open(outfile, 'rb')
             data = fp.read()
             fp.close()
 
             # skip binary files
             if b('\0') in data:
                 continue
 
             data = data.replace(b('@LIBDIR@'), libdir.encode(libdir_escape))
             fp = open(outfile, 'wb')
             fp.write(data)
             fp.close()
 
 cmdclass = {'build': hgbuild,
             'build_mo': hgbuildmo,
             'build_ext': hgbuildext,
             'build_py': hgbuildpy,
             'build_hgextindex': buildhgextindex,
             'install_lib': hginstalllib,
             'install_scripts': hginstallscripts,
             'build_hgexe': buildhgexe,
             }
 
 packages = ['mercurial', 'mercurial.hgweb', 'mercurial.httpclient',
             'hgext', 'hgext.convert', 'hgext.highlight', 'hgext.zeroconf',
             'hgext.largefiles']
 
 pymodules = []
 
 common_depends = ['mercurial/util.h']
 
 extmodules = [
     Extension('mercurial.base85', ['mercurial/base85.c'],
               depends=common_depends),
     Extension('mercurial.bdiff', ['mercurial/bdiff.c'],
               depends=common_depends),
     Extension('mercurial.diffhelpers', ['mercurial/diffhelpers.c'],
               depends=common_depends),
     Extension('mercurial.mpatch', ['mercurial/mpatch.c'],
               depends=common_depends),
     Extension('mercurial.parsers', ['mercurial/dirs.c',
                                     'mercurial/parsers.c',
                                     'mercurial/pathencode.c'],
               depends=common_depends),
     ]
 
 osutil_ldflags = []
 
 if sys.platform == 'darwin':
     osutil_ldflags += ['-framework', 'ApplicationServices']
 
 # disable osutil.c under windows + python 2.4 (issue1364)
 if sys.platform == 'win32' and sys.version_info < (2, 5, 0, 'final'):
     pymodules.append('mercurial.pure.osutil')
 else:
     extmodules.append(Extension('mercurial.osutil', ['mercurial/osutil.c'],
                                 extra_link_args=osutil_ldflags,
                                 depends=common_depends))
 
-# the -mno-cygwin option has been deprecated for years
-Mingw32CCompiler = cygwinccompiler.Mingw32CCompiler
+try:
+    from distutils import cygwinccompiler
+
+    # the -mno-cygwin option has been deprecated for years
+    compiler = cygwinccompiler.Mingw32CCompiler
 
-class HackedMingw32CCompiler(cygwinccompiler.Mingw32CCompiler):
-    def __init__(self, *args, **kwargs):
-        Mingw32CCompiler.__init__(self, *args, **kwargs)
-        for i in 'compiler compiler_so linker_exe linker_so'.split():
-            try:
-                getattr(self, i).remove('-mno-cygwin')
-            except ValueError:
-                pass
+    class HackedMingw32CCompiler(cygwinccompiler.Mingw32CCompiler):
+        def __init__(self, *args, **kwargs):
+            compiler.__init__(self, *args, **kwargs)
+            for i in 'compiler compiler_so linker_exe linker_so'.split():
+                try:
+                    getattr(self, i).remove('-mno-cygwin')
+                except ValueError:
+                    pass
 
-cygwinccompiler.Mingw32CCompiler = HackedMingw32CCompiler
+    cygwinccompiler.Mingw32CCompiler = HackedMingw32CCompiler
+except ImportError:
+    # the cygwinccompiler package is not available on some Python
+    # distributions like the ones from the optware project for Synology
+    # DiskStation boxes
+    class HackedMingw32CCompiler(object):
+        pass
 
 packagedata = {'mercurial': ['locale/*/LC_MESSAGES/hg.mo',
                              'help/*.txt',
                              'default.d/*.rc',
                              'dummycert.pem']}
 
 def ordinarypath(p):
     return p and p[0] != '.' and p[-1] != '~'
 
 for root in ('templates',):
     for curdir, dirs, files in os.walk(os.path.join('mercurial', root)):
         curdir = curdir.split(os.sep, 1)[1]
         dirs[:] = filter(ordinarypath, dirs)
         for f in filter(ordinarypath, files):
             f = os.path.join(curdir, f)
             packagedata['mercurial'].append(f)
 
 datafiles = []
 setupversion = version
 extra = {}
 
 if py2exeloaded:
     extra['console'] = [
         {'script':'hg',
          'copyright':'Copyright (C) 2005-2010 Matt Mackall and others',
          'product_version':version}]
     # sub command of 'build' because 'py2exe' does not handle sub_commands
     build.sub_commands.insert(0, ('build_hgextindex', None))
 
 if os.name == 'nt':
     # Windows binary file versions for exe/dll files must have the
     # form W.X.Y.Z, where W,X,Y,Z are numbers in the range 0..65535
     setupversion = version.split('+', 1)[0]
 
 if sys.platform == 'darwin' and os.path.exists('/usr/bin/xcodebuild'):
     version = runcmd(['/usr/bin/xcodebuild', '-version'], {})[0].splitlines()
     if version:
         version = version[0]
         xcode4 = (version.startswith('Xcode') and
                   StrictVersion(version.split()[1]) >= StrictVersion('4.0'))
         xcode51 = re.match(r'^Xcode\s+5\.1', version) is not None
     else:
         # xcodebuild returns empty on OS X Lion with XCode 4.3 not
         # installed, but instead with only command-line tools. Assume
         # that only happens on >= Lion, thus no PPC support.
         xcode4 = True
         xcode51 = False
 
     # XCode 4.0 dropped support for ppc architecture, which is hardcoded in
     # distutils.sysconfig
     if xcode4:
         os.environ['ARCHFLAGS'] = ''
 
     # XCode 5.1 changes clang such that it now fails to compile if the
     # -mno-fused-madd flag is passed, but the version of Python shipped with
     # OS X 10.9 Mavericks includes this flag. This causes problems in all
     # C extension modules, and a bug has been filed upstream at
     # http://bugs.python.org/issue21244. We also need to patch this here
     # so Mercurial can continue to compile in the meantime.
     if xcode51:
         cflags = get_config_var('CFLAGS')
         if cflags and re.search(r'-mno-fused-madd\b', cflags) is not None:
             os.environ['CFLAGS'] = (
                 os.environ.get('CFLAGS', '') + ' -Qunused-arguments')
 
 setup(name='mercurial',
       version=setupversion,
       author='Matt Mackall and many others',
       author_email='[e-mail]',
       url='http://mercurial.selenic.com/',
       download_url='http://mercurial.selenic.com/release/',
       description=('Fast scalable distributed SCM (revision control, version '
                    'control) system'),
       long_description=('Mercurial is a distributed SCM tool written in Python.'
                         ' It is used by a number of large projects that require'
                         ' fast, reliable distributed revision control, such as '
                         'Mozilla.'),
       license='GNU GPLv2 or any later version',
       classifiers=[
           'Development Status :: 6 - Mature',
           'Environment :: Console',
           'Intended Audience :: Developers',
           'Intended Audience :: System Administrators',
           'License :: OSI Approved :: GNU General Public License (GPL)',
           'Natural Language :: Danish',
           'Natural Language :: English',
           'Natural Language :: German',
           'Natural Language :: Italian',
           'Natural Language :: Japanese',
           'Natural Language :: Portuguese (Brazilian)',
           'Operating System :: Microsoft :: Windows',
           'Operating System :: OS Independent',
           'Operating System :: POSIX',
           'Programming Language :: C',
           'Programming Language :: Python',
           'Topic :: Software Development :: Version Control',
       ],
       scripts=scripts,
       packages=packages,
       py_modules=pymodules,
       ext_modules=extmodules,
       data_files=datafiles,
       package_data=packagedata,
       cmdclass=cmdclass,
       distclass=hgdist,
       options={'py2exe': {'packages': ['hgext', 'email']},
                'bdist_mpkg': {'zipdist': False,
                               'license': 'COPYING',
                               'readme': 'contrib/macosx/Readme.html',
                               'welcome': 'contrib/macosx/Welcome.html',
                               },
                },
       **extra)