/setuptools/command/easy_install.py

#!python
"""\
Easy Install
------------

A tool for doing automatic download/extract/build of distutils-based Python
packages.  For detailed documentation, see the accompanying EasyInstall.txt
file, or visit the `EasyInstall home page`__.

__ http://packages.python.org/distribute/easy_install.html

"""
import sys
import os
import zipimport
import shutil
import tempfile
import zipfile
import re
import stat
import random
from glob import glob
from setuptools import Command, _dont_write_bytecode
from setuptools.sandbox import run_setup
from distutils import log, dir_util
from distutils.util import get_platform
from distutils.util import convert_path, subst_vars
from distutils.sysconfig import get_python_lib, get_config_vars
from distutils.errors import DistutilsArgError, DistutilsOptionError, \
    DistutilsError, DistutilsPlatformError
from distutils.command.install import INSTALL_SCHEMES, SCHEME_KEYS
from setuptools.command import setopt
from setuptools.archive_util import unpack_archive
from setuptools.package_index import PackageIndex
from setuptools.package_index import URL_SCHEME
from setuptools.command import bdist_egg, egg_info
from pkg_resources import yield_lines, normalize_path, resource_string, \
        ensure_directory, get_distribution, find_distributions, \
        Environment, Requirement, Distribution, \
        PathMetadata, EggMetadata, WorkingSet, \
         DistributionNotFound, VersionConflict, \
        DEVELOP_DIST

sys_executable = os.path.normpath(sys.executable)

__all__ = [
    'samefile', 'easy_install', 'PthDistributions', 'extract_wininst_cfg',
    'main', 'get_exe_prefixes',
]

import site
HAS_USER_SITE = not sys.version < "2.6" and site.ENABLE_USER_SITE

import struct
def is_64bit():
    return struct.calcsize("P") == 8

def samefile(p1,p2):
    if hasattr(os.path,'samefile') and (
        os.path.exists(p1) and os.path.exists(p2)
    ):
        return os.path.samefile(p1,p2)
    return (
        os.path.normpath(os.path.normcase(p1)) ==
        os.path.normpath(os.path.normcase(p2))
    )

if sys.version_info <= (3,):
    def _to_ascii(s):
        return s
    def isascii(s):
        try:
            unicode(s, 'ascii')
            return True
        except UnicodeError:
            return False
else:
    def _to_ascii(s):
        return s.encode('ascii')
    def isascii(s):
        try:
            s.encode('ascii')
            return True
        except UnicodeError:
            return False

class easy_install(Command):
    """Manage a download/build/install process"""
    description = "Find/get/install Python packages"
    command_consumes_arguments = True

    user_options = [
        ('prefix=', None, "installation prefix"),
        ("zip-ok", "z", "install package as a zipfile"),
        ("multi-version", "m", "make apps have to require() a version"),
        ("upgrade", "U", "force upgrade (searches PyPI for latest versions)"),
        ("install-dir=", "d", "install package to DIR"),
        ("script-dir=", "s", "install scripts to DIR"),
        ("exclude-scripts", "x", "Don't install scripts"),
        ("always-copy", "a", "Copy all needed packages to install dir"),
        ("index-url=", "i", "base URL of Python Package Index"),
        ("find-links=", "f", "additional URL(s) to search for packages"),
        ("delete-conflicting", "D", "no longer needed; don't use this"),
        ("ignore-conflicts-at-my-risk", None,
            "no longer needed; don't use this"),
        ("build-directory=", "b",
            "download/extract/build in DIR; keep the results"),
        ('optimize=', 'O',
         "also compile with optimization: -O1 for \"python -O\", "
         "-O2 for \"python -OO\", and -O0 to disable [default: -O0]"),
        ('record=', None,
         "filename in which to record list of installed files"),
        ('always-unzip', 'Z', "don't install as a zipfile, no matter what"),
        ('site-dirs=','S',"list of directories where .pth files work"),
        ('editable', 'e', "Install specified packages in editable form"),
        ('no-deps', 'N', "don't install dependencies"),
        ('allow-hosts=', 'H', "pattern(s) that hostnames must match"),
        ('local-snapshots-ok', 'l', "allow building eggs from local checkouts"),
        ('version', None, "print version information and exit"),
        ('no-find-links', None,
         "Don't load find-links defined in packages being installed")
    ]
    boolean_options = [
        'zip-ok', 'multi-version', 'exclude-scripts', 'upgrade', 'always-copy',
        'delete-conflicting', 'ignore-conflicts-at-my-risk', 'editable',
        'no-deps', 'local-snapshots-ok', 'version'
    ]

    if HAS_USER_SITE:
        user_options.append(('user', None,
                             "install in user site-package '%s'" % site.USER_SITE))
        boolean_options.append('user')


    negative_opt = {'always-unzip': 'zip-ok'}
    create_index = PackageIndex

    def initialize_options(self):
        if HAS_USER_SITE:
            whereami = os.path.abspath(__file__)
            self.user = whereami.startswith(site.USER_SITE)
        else:
            self.user = 0

        self.zip_ok = self.local_snapshots_ok = None
        self.install_dir = self.script_dir = self.exclude_scripts = None
        self.index_url = None
        self.find_links = None
        self.build_directory = None
        self.args = None
        self.optimize = self.record = None
        self.upgrade = self.always_copy = self.multi_version = None
        self.editable = self.no_deps = self.allow_hosts = None
        self.root = self.prefix = self.no_report = None
        self.version = None
        self.install_purelib = None     # for pure module distributions
        self.install_platlib = None     # non-pure (dists w/ extensions)
        self.install_headers = None     # for C/C++ headers
        self.install_lib = None         # set to either purelib or platlib
        self.install_scripts = None
        self.install_data = None
        self.install_base = None
        self.install_platbase = None
        if HAS_USER_SITE:
            self.install_userbase = site.USER_BASE
            self.install_usersite = site.USER_SITE
        else:
            self.install_userbase = None
            self.install_usersite = None
        self.no_find_links = None

        # Options not specifiable via command line
        self.package_index = None
        self.pth_file = self.always_copy_from = None
        self.delete_conflicting = None
        self.ignore_conflicts_at_my_risk = None
        self.site_dirs = None
        self.installed_projects = {}
        self.sitepy_installed = False
        # Always read easy_install options, even if we are subclassed, or have
        # an independent instance created.  This ensures that defaults will
        # always come from the standard configuration file(s)' "easy_install"
        # section, even if this is a "develop" or "install" command, or some
        # other embedding.
        self._dry_run = None
        self.verbose = self.distribution.verbose
        self.distribution._set_command_options(
            self, self.distribution.get_option_dict('easy_install')
        )

    def delete_blockers(self, blockers):
        for filename in blockers:
            if os.path.exists(filename) or os.path.islink(filename):
                log.info("Deleting %s", filename)
                if not self.dry_run:
                    if os.path.isdir(filename) and not os.path.islink(filename):
                        rmtree(filename)
                    else:
                        os.unlink(filename)

    def finalize_options(self):
        if self.version:
            print 'distribute %s' % get_distribution('distribute').version
            sys.exit()

        py_version = sys.version.split()[0]
        prefix, exec_prefix = get_config_vars('prefix', 'exec_prefix')

        self.config_vars = {'dist_name': self.distribution.get_name(),
                            'dist_version': self.distribution.get_version(),
                            'dist_fullname': self.distribution.get_fullname(),
                            'py_version': py_version,
                            'py_version_short': py_version[0:3],
                            'py_version_nodot': py_version[0] + py_version[2],
                            'sys_prefix': prefix,
                            'prefix': prefix,
                            'sys_exec_prefix': exec_prefix,
                            'exec_prefix': exec_prefix,
                            # Only python 3.2+ has abiflags
                            'abiflags': getattr(sys, 'abiflags', ''),
                           }

        if HAS_USER_SITE:
            self.config_vars['userbase'] = self.install_userbase
            self.config_vars['usersite'] = self.install_usersite

        # fix the install_dir if "--user" was used
        #XXX: duplicate of the code in the setup command
        if self.user and HAS_USER_SITE:
            self.create_home_path()
            if self.install_userbase is None:
                raise DistutilsPlatformError(
                    "User base directory is not specified")
            self.install_base = self.install_platbase = self.install_userbase
            if os.name == 'posix':
                self.select_scheme("unix_user")
            else:
                self.select_scheme(os.name + "_user")

        self.expand_basedirs()
        self.expand_dirs()

        self._expand('install_dir','script_dir','build_directory','site_dirs')
        # If a non-default installation directory was specified, default the
        # script directory to match it.
        if self.script_dir is None:
            self.script_dir = self.install_dir

        if self.no_find_links is None:
            self.no_find_links = False

        # Let install_dir get set by install_lib command, which in turn
        # gets its info from the install command, and takes into account
        # --prefix and --home and all that other crud.
        self.set_undefined_options('install_lib',
            ('install_dir','install_dir')
        )
        # Likewise, set default script_dir from 'install_scripts.install_dir'
        self.set_undefined_options('install_scripts',
            ('install_dir', 'script_dir')
        )

        if self.user and self.install_purelib:
            self.install_dir = self.install_purelib
            self.script_dir = self.install_scripts
        # default --record from the install command
        self.set_undefined_options('install', ('record', 'record'))
        normpath = map(normalize_path, sys.path)
        self.all_site_dirs = get_site_dirs()
        if self.site_dirs is not None:
            site_dirs = [
                os.path.expanduser(s.strip()) for s in self.site_dirs.split(',')
            ]
            for d in site_dirs:
                if not os.path.isdir(d):
                    log.warn("%s (in --site-dirs) does not exist", d)
                elif normalize_path(d) not in normpath:
                    raise DistutilsOptionError(
                        d+" (in --site-dirs) is not on sys.path"
                    )
                else:
                    self.all_site_dirs.append(normalize_path(d))
        if not self.editable: self.check_site_dir()
        self.index_url = self.index_url or "http://pypi.python.org/simple"
        self.shadow_path = self.all_site_dirs[:]
        for path_item in self.install_dir, normalize_path(self.script_dir):
            if path_item not in self.shadow_path:
                self.shadow_path.insert(0, path_item)

        if self.allow_hosts is not None:
            hosts = [s.strip() for s in self.allow_hosts.split(',')]
        else:
            hosts = ['*']
        if self.package_index is None:
            self.package_index = self.create_index(
                self.index_url, search_path = self.shadow_path, hosts=hosts,
            )
        self.local_index = Environment(self.shadow_path+sys.path)

        if self.find_links is not None:
            if isinstance(self.find_links, basestring):
                self.find_links = self.find_links.split()
        else:
            self.find_links = []
        if self.local_snapshots_ok:
            self.package_index.scan_egg_links(self.shadow_path+sys.path)
        if not self.no_find_links:
            self.package_index.add_find_links(self.find_links)
        self.set_undefined_options('install_lib', ('optimize','optimize'))
        if not isinstance(self.optimize,int):
            try:
                self.optimize = int(self.optimize)
                if not (0 <= self.optimize <= 2): raise ValueError
            except ValueError:
                raise DistutilsOptionError("--optimize must be 0, 1, or 2")

        if self.delete_conflicting and self.ignore_conflicts_at_my_risk:
            raise DistutilsOptionError(
                "Can't use both --delete-conflicting and "
                "--ignore-conflicts-at-my-risk at the same time"
            )
        if self.editable and not self.build_directory:
            raise DistutilsArgError(
                "Must specify a build directory (-b) when using --editable"
            )
        if not self.args:
            raise DistutilsArgError(
                "No urls, filenames, or requirements specified (see --help)")

        self.outputs = []


    def _expand_attrs(self, attrs):
        for attr in attrs:
            val = getattr(self, attr)
            if val is not None:
                if os.name == 'posix' or os.name == 'nt':
                    val = os.path.expanduser(val)
                val = subst_vars(val, self.config_vars)
                setattr(self, attr, val)

    def expand_basedirs(self):
        """Calls `os.path.expanduser` on install_base, install_platbase and
        root."""
        self._expand_attrs(['install_base', 'install_platbase', 'root'])

    def expand_dirs(self):
        """Calls `os.path.expanduser` on install dirs."""
        self._expand_attrs(['install_purelib', 'install_platlib',
                            'install_lib', 'install_headers',
                            'install_scripts', 'install_data',])

    def run(self):
        if self.verbose != self.distribution.verbose:
            log.set_verbosity(self.verbose)
        try:
            for spec in self.args:
                self.easy_install(spec, not self.no_deps)
            if self.record:
                outputs = self.outputs
                if self.root:               # strip any package prefix
                    root_len = len(self.root)
                    for counter in xrange(len(outputs)):
                        outputs[counter] = outputs[counter][root_len:]
                from distutils import file_util
                self.execute(
                    file_util.write_file, (self.record, outputs),
                    "writing list of installed files to '%s'" %
                    self.record
                )
            self.warn_deprecated_options()
        finally:
            log.set_verbosity(self.distribution.verbose)

    def pseudo_tempname(self):
        """Return a pseudo-tempname base in the install directory.
        This code is intentionally naive; if a malicious party can write to
        the target directory you're already in deep doodoo.
        """
        try:
            pid = os.getpid()
        except:
            pid = random.randint(0,sys.maxint)
        return os.path.join(self.install_dir, "test-easy-install-%s" % pid)

    def warn_deprecated_options(self):
        if self.delete_conflicting or self.ignore_conflicts_at_my_risk:
            log.warn(
                "Note: The -D, --delete-conflicting and"
                " --ignore-conflicts-at-my-risk no longer have any purpose"
                " and should not be used."
            )

    def check_site_dir(self):
        """Verify that self.install_dir is .pth-capable dir, if needed"""

        instdir = normalize_path(self.install_dir)
        pth_file = os.path.join(instdir,'easy-install.pth')

        # Is it a configured, PYTHONPATH, implicit, or explicit site dir?
        is_site_dir = instdir in self.all_site_dirs

        if not is_site_dir:
            # No?  Then directly test whether it does .pth file processing
            is_site_dir = self.check_pth_processing()
        else:
            # make sure we can write to target dir
            testfile = self.pseudo_tempname()+'.write-test'
            test_exists = os.path.exists(testfile)
            try:
                if test_exists: os.unlink(testfile)
                open(testfile,'w').close()
                os.unlink(testfile)
            except (OSError,IOError):
                self.cant_write_to_target()

        if not is_site_dir and not self.multi_version:
            # Can't install non-multi to non-site dir
            raise DistutilsError(self.no_default_version_msg())

        if is_site_dir:
            if self.pth_file is None:
                self.pth_file = PthDistributions(pth_file, self.all_site_dirs)
        else:
            self.pth_file = None

        PYTHONPATH = os.environ.get('PYTHONPATH','').split(os.pathsep)
        if instdir not in map(normalize_path, filter(None,PYTHONPATH)):
            # only PYTHONPATH dirs need a site.py, so pretend it's there
            self.sitepy_installed = True
        elif self.multi_version and not os.path.exists(pth_file):
            self.sitepy_installed = True    # don't need site.py in this case
            self.pth_file = None            # and don't create a .pth file
        self.install_dir = instdir

    def cant_write_to_target(self):
        msg = """can't create or remove files in install directory

The following error occurred while trying to add or remove files in the
installation directory:

    %s

The installation directory you specified (via --install-dir, --prefix, or
the distutils default setting) was:

    %s
"""     % (sys.exc_info()[1], self.install_dir,)

        if not os.path.exists(self.install_dir):
            msg += """
This directory does not currently exist.  Please create it and try again, or
choose a different installation directory (using the -d or --install-dir
option).
"""
        else:
            msg += """
Perhaps your account does not have write access to this directory?  If the
installation directory is a system-owned directory, you may need to sign in
as the administrator or "root" account.  If you do not have administrative
access to this machine, you may wish to choose a different installation
directory, preferably one that is listed in your PYTHONPATH environment
variable.

For information on other options, you may wish to consult the
documentation at:

  http://packages.python.org/distribute/easy_install.html

Please make the appropriate changes for your system and try again.
"""
        raise DistutilsError(msg)




    def check_pth_processing(self):
        """Empirically verify whether .pth files are supported in inst. dir"""
        instdir = self.install_dir
        log.info("Checking .pth file support in %s", instdir)
        pth_file = self.pseudo_tempname()+".pth"
        ok_file = pth_file+'.ok'
        ok_exists = os.path.exists(ok_file)
        try:
            if ok_exists: os.unlink(ok_file)
            dirname = os.path.dirname(ok_file)
            if not os.path.exists(dirname):
                os.makedirs(dirname)
            f = open(pth_file,'w')
        except (OSError,IOError):
            self.cant_write_to_target()
        else:
            try:
                f.write("import os;open(%r,'w').write('OK')\n" % (ok_file,))
                f.close(); f=None
                executable = sys.executable
                if os.name=='nt':
                    dirname,basename = os.path.split(executable)
                    alt = os.path.join(dirname,'pythonw.exe')
                    if basename.lower()=='python.exe' and os.path.exists(alt):
                        # use pythonw.exe to avoid opening a console window
                        executable = alt

                from distutils.spawn import spawn
                spawn([executable,'-E','-c','pass'],0)

                if os.path.exists(ok_file):
                    log.info(
                        "TEST PASSED: %s appears to support .pth files",
                        instdir
                    )
                    return True
            finally:
                if f: f.close()
                if os.path.exists(ok_file): os.unlink(ok_file)
                if os.path.exists(pth_file): os.unlink(pth_file)
        if not self.multi_version:
            log.warn("TEST FAILED: %s does NOT support .pth files", instdir)
        return False

    def install_egg_scripts(self, dist):
        """Write all the scripts for `dist`, unless scripts are excluded"""
        if not self.exclude_scripts and dist.metadata_isdir('scripts'):
            for script_name in dist.metadata_listdir('scripts'):
                self.install_script(
                    dist, script_name,
                    dist.get_metadata('scripts/'+script_name)
                )
        self.install_wrapper_scripts(dist)

    def add_output(self, path):
        if os.path.isdir(path):
            for base, dirs, files in os.walk(path):
                for filename in files:
                    self.outputs.append(os.path.join(base,filename))
        else:
            self.outputs.append(path)

    def not_editable(self, spec):
        if self.editable:
            raise DistutilsArgError(
                "Invalid argument %r: you can't use filenames or URLs "
                "with --editable (except via the --find-links option)."
                % (spec,)
            )

    def check_editable(self,spec):
        if not self.editable:
            return

        if os.path.exists(os.path.join(self.build_directory, spec.key)):
            raise DistutilsArgError(
                "%r already exists in %s; can't do a checkout there" %
                (spec.key, self.build_directory)
            )






    def easy_install(self, spec, deps=False):
        tmpdir = tempfile.mkdtemp(prefix="easy_install-")
        download = None
        if not self.editable: self.install_site_py()

        try:
            if not isinstance(spec,Requirement):
                if URL_SCHEME(spec):
                    # It's a url, download it to tmpdir and process
                    self.not_editable(spec)
                    download = self.package_index.download(spec, tmpdir)
                    return self.install_item(None, download, tmpdir, deps, True)

                elif os.path.exists(spec):
                    # Existing file or directory, just process it directly
                    self.not_editable(spec)
                    return self.install_item(None, spec, tmpdir, deps, True)
                else:
                    spec = parse_requirement_arg(spec)

            self.check_editable(spec)
            dist = self.package_index.fetch_distribution(
                spec, tmpdir, self.upgrade, self.editable, not self.always_copy,
                self.local_index
            )

            if dist is None:
                msg = "Could not find suitable distribution for %r" % spec
                if self.always_copy:
                    msg+=" (--always-copy skips system and development eggs)"
                raise DistutilsError(msg)
            elif dist.precedence==DEVELOP_DIST:
                # .egg-info dists don't need installing, just process deps
                self.process_distribution(spec, dist, deps, "Using")
                return dist
            else:
                return self.install_item(spec, dist.location, tmpdir, deps)

        finally:
            if os.path.exists(tmpdir):
                rmtree(tmpdir)

    def install_item(self, spec, download, tmpdir, deps, install_needed=False):

        # Installation is also needed if file in tmpdir or is not an egg
        install_needed = install_needed or self.always_copy
        install_needed = install_needed or os.path.dirname(download) == tmpdir
        install_needed = install_needed or not download.endswith('.egg')
        install_needed = install_needed or (
            self.always_copy_from is not None and
            os.path.dirname(normalize_path(download)) ==
            normalize_path(self.always_copy_from)
        )

        if spec and not install_needed:
            # at this point, we know it's a local .egg, we just don't know if
            # it's already installed.
            for dist in self.local_index[spec.project_name]:
                if dist.location==download:
                    break
            else:
                install_needed = True   # it's not in the local index

        log.info("Processing %s", os.path.basename(download))

        if install_needed:
            dists = self.install_eggs(spec, download, tmpdir)
            for dist in dists:
                self.process_distribution(spec, dist, deps)
        else:
            dists = [self.check_conflicts(self.egg_distribution(download))]
            self.process_distribution(spec, dists[0], deps, "Using")

        if spec is not None:
            for dist in dists:
                if dist in spec:
                    return dist



    def select_scheme(self, name):
        """Sets the install directories by applying the install schemes."""
        # it's the caller's problem if they supply a bad name!
        scheme = INSTALL_SCHEMES[name]
        for key in SCHEME_KEYS:
            attrname = 'install_' + key
            if getattr(self, attrname) is None:
                setattr(self, attrname, scheme[key])




    def process_distribution(self, requirement, dist, deps=True, *info):
        self.update_pth(dist)
        self.package_index.add(dist)
        self.local_index.add(dist)
        if not self.editable:
            self.install_egg_scripts(dist)
        self.installed_projects[dist.key] = dist
        log.info(self.installation_report(requirement, dist, *info))
        if (dist.has_metadata('dependency_links.txt') and
            not self.no_find_links):
            self.package_index.add_find_links(
                dist.get_metadata_lines('dependency_links.txt')
            )
        if not deps and not self.always_copy:
            return
        elif requirement is not None and dist.key != requirement.key:
            log.warn("Skipping dependencies for %s", dist)
            return  # XXX this is not the distribution we were looking for
        elif requirement is None or dist not in requirement:
            # if we wound up with a different version, resolve what we've got
            distreq = dist.as_requirement()
            requirement = requirement or distreq
            requirement = Requirement(
                distreq.project_name, distreq.specs, requirement.extras
            )
        log.info("Processing dependencies for %s", requirement)
        try:
            distros = WorkingSet([]).resolve(
                [requirement], self.local_index, self.easy_install
            )
        except DistributionNotFound, e:
            raise DistutilsError(
                "Could not find required distribution %s" % e.args
            )
        except VersionConflict, e:
            raise DistutilsError(
                "Installed distribution %s conflicts with requirement %s"
                % e.args
            )
        if self.always_copy or self.always_copy_from:
            # Force all the relevant distros to be copied or activated
            for dist in distros:
                if dist.key not in self.installed_projects:
                    self.easy_install(dist.as_requirement())
        log.info("Finished processing dependencies for %s", requirement)

    def should_unzip(self, dist):
        if self.zip_ok is not None:
            return not self.zip_ok
        if dist.has_metadata('not-zip-safe'):
            return True
        if not dist.has_metadata('zip-safe'):
            return True
        return True

    def maybe_move(self, spec, dist_filename, setup_base):
        dst = os.path.join(self.build_directory, spec.key)
        if os.path.exists(dst):
            log.warn(
               "%r already exists in %s; build directory %s will not be kept",
               spec.key, self.build_directory, setup_base
            )
            return setup_base
        if os.path.isdir(dist_filename):
            setup_base = dist_filename
        else:
            if os.path.dirname(dist_filename)==setup_base:
                os.unlink(dist_filename)   # get it out of the tmp dir
            contents = os.listdir(setup_base)
            if len(contents)==1:
                dist_filename = os.path.join(setup_base,contents[0])
                if os.path.isdir(dist_filename):
                    # if the only thing there is a directory, move it instead
                    setup_base = dist_filename
        ensure_directory(dst); shutil.move(setup_base, dst)
        return dst

    def install_wrapper_scripts(self, dist):
        if not self.exclude_scripts:
            for args in get_script_args(dist):
                self.write_script(*args)



    def install_script(self, dist, script_name, script_text, dev_path=None):
        """Generate a legacy script wrapper and install it"""
        spec = str(dist.as_requirement())
        is_script = is_python_script(script_text, script_name)

        def get_template(filename):
            """
            There are a couple of template scripts in the package. This
            function loads one of them and prepares it for use.

            These templates use triple-quotes to escape variable
            substitutions so the scripts get the 2to3 treatment when build
            on Python 3. The templates cannot use triple-quotes naturally.
            """
            raw_bytes = resource_string('setuptools', template_name)
            template_str = raw_bytes.decode('utf-8')
            clean_template = template_str.replace('"""', '')
            return clean_template

        if is_script:
            template_name = 'script template.py'
            if dev_path:
                template_name = template_name.replace('.py', ' (dev).py')
            script_text = (get_script_header(script_text) +
                get_template(template_name) % locals())
        self.write_script(script_name, _to_ascii(script_text), 'b')

    def write_script(self, script_name, contents, mode="t", blockers=()):
        """Write an executable file to the scripts directory"""
        self.delete_blockers(   # clean up old .py/.pyw w/o a script
            [os.path.join(self.script_dir,x) for x in blockers])
        log.info("Installing %s script to %s", script_name, self.script_dir)
        target = os.path.join(self.script_dir, script_name)
        self.add_output(target)

        mask = current_umask()
        if not self.dry_run:
            ensure_directory(target)
            f = open(target,"w"+mode)
            f.write(contents)
            f.close()
            chmod(target, 0777-mask)




    def install_eggs(self, spec, dist_filename, tmpdir):
        # .egg dirs or files are already built, so just return them
        if dist_filename.lower().endswith('.egg'):
            return [self.install_egg(dist_filename, tmpdir)]
        elif dist_filename.lower().endswith('.exe'):
            return [self.install_exe(dist_filename, tmpdir)]

        # Anything else, try to extract and build
        setup_base = tmpdir
        if os.path.isfile(dist_filename) and not dist_filename.endswith('.py'):
            unpack_archive(dist_filename, tmpdir, self.unpack_progress)
        elif os.path.isdir(dist_filename):
            setup_base = os.path.abspath(dist_filename)

        if (setup_base.startswith(tmpdir)   # something we downloaded
            and self.build_directory and spec is not None
        ):
            setup_base = self.maybe_move(spec, dist_filename, setup_base)

        # Find the setup.py file
        setup_script = os.path.join(setup_base, 'setup.py')

        if not os.path.exists(setup_script):
            setups = glob(os.path.join(setup_base, '*', 'setup.py'))
            if not setups:
                raise DistutilsError(
                    "Couldn't find a setup script in %s" % os.path.abspath(dist_filename)
                )
            if len(setups)>1:
                raise DistutilsError(
                    "Multiple setup scripts in %s" % os.path.abspath(dist_filename)
                )
            setup_script = setups[0]

        # Now run it, and return the result
        if self.editable:
            log.info(self.report_editable(spec, setup_script))
            return []
        else:
            return self.build_and_install(setup_script, setup_base)

    def egg_distribution(self, egg_path):
        if os.path.isdir(egg_path):
            metadata = PathMetadata(egg_path,os.path.join(egg_path,'EGG-INFO'))
        else:
            metadata = EggMetadata(zipimport.zipimporter(egg_path))
        return Distribution.from_filename(egg_path,metadata=metadata)

    def install_egg(self, egg_path, tmpdir):
        destination = os.path.join(self.install_dir,os.path.basename(egg_path))
        destination = os.path.abspath(destination)
        if not self.dry_run:
            ensure_directory(destination)

        dist = self.egg_distribution(egg_path)
        self.check_conflicts(dist)
        if not samefile(egg_path, destination):
            if os.path.isdir(destination) and not os.path.islink(destination):
                dir_util.remove_tree(destination, dry_run=self.dry_run)
            elif os.path.exists(destination):
                self.execute(os.unlink,(destination,),"Removing "+destination)
            uncache_zipdir(destination)
            if os.path.isdir(egg_path):
                if egg_path.startswith(tmpdir):
                    f,m = shutil.move, "Moving"
                else:
                    f,m = shutil.copytree, "Copying"
            elif self.should_unzip(dist):
                self.mkpath(destination)
                f,m = self.unpack_and_compile, "Extracting"
            elif egg_path.startswith(tmpdir):
                f,m = shutil.move, "Moving"
            else:
                f,m = shutil.copy2, "Copying"

            self.execute(f, (egg_path, destination),
                (m+" %s to %s") %
                (os.path.basename(egg_path),os.path.dirname(destination)))

        self.add_output(destination)
        return self.egg_distribution(destination)

    def install_exe(self, dist_filename, tmpdir):
        # See if it's valid, get data
        cfg = extract_wininst_cfg(dist_filename)
        if cfg is None:
            raise DistutilsError(
                "%s is not a valid distutils Windows .exe" % dist_filename
            )
        # Create a dummy distribution object until we build the real distro
        dist = Distribution(None,
            project_name=cfg.get('metadata','name'),
            version=cfg.get('metadata','version'), platform=get_platform()
        )

        # Convert the .exe to an unpacked egg
        egg_path = dist.location = os.path.join(tmpdir, dist.egg_name()+'.egg')
        egg_tmp  = egg_path+'.tmp'
        egg_info = os.path.join(egg_tmp, 'EGG-INFO')
        pkg_inf = os.path.join(egg_info, 'PKG-INFO')
        ensure_directory(pkg_inf)   # make sure EGG-INFO dir exists
        dist._provider = PathMetadata(egg_tmp, egg_info)    # XXX
        self.exe_to_egg(dist_filename, egg_tmp)

        # Write EGG-INFO/PKG-INFO
        if not os.path.exists(pkg_inf):
            f = open(pkg_inf,'w')
            f.write('Metadata-Version: 1.0\n')
            for k,v in cfg.items('metadata'):
                if k<>'target_version':
                    f.write('%s: %s\n' % (k.replace('_','-').title(), v))
            f.close()
        script_dir = os.path.join(egg_info,'scripts')
        self.delete_blockers(   # delete entry-point scripts to avoid duping
            [os.path.join(script_dir,args[0]) for args in get_script_args(dist)]
        )
        # Build .egg file from tmpdir
        bdist_egg.make_zipfile(
            egg_path, egg_tmp, verbose=self.verbose, dry_run=self.dry_run
        )
        # install the .egg
        return self.install_egg(egg_path, tmpdir)

    def exe_to_egg(self, dist_filename, egg_tmp):
        """Extract a bdist_wininst to the directories an egg would use"""
        # Check for .pth file and set up prefix translations
        prefixes = get_exe_prefixes(dist_filename)
        to_compile = []
        native_libs = []
        top_level = {}
        def process(src,dst):
            s = src.lower()
            for old,new in prefixes:
                if s.startswith(old):
                    src = new+src[len(old):]
                    parts = src.split('/')
                    dst = os.path.join(egg_tmp, *parts)
                    dl = dst.lower()
                    if dl.endswith('.pyd') or dl.endswith('.dll'):
                        parts[-1] = bdist_egg.strip_module(parts[-1])
                        top_level[os.path.splitext(parts[0])[0]] = 1
                        native_libs.append(src)
                    elif dl.endswith('.py') and old!='SCRIPTS/':
                        top_level[os.path.splitext(parts[0])[0]] = 1
                        to_compile.append(dst)
                    return dst
            if not src.endswith('.pth'):
                log.warn("WARNING: can't process %s", src)
            return None
        # extract, tracking .pyd/.dll->native_libs and .py -> to_compile
        unpack_archive(dist_filename, egg_tmp, process)
        stubs = []
        for res in native_libs:
            if res.lower().endswith('.pyd'):    # create stubs for .pyd's
                parts = res.split('/')
                resource = parts[-1]
                parts[-1] = bdist_egg.strip_module(parts[-1])+'.py'
                pyfile = os.path.join(egg_tmp, *parts)
                to_compile.append(pyfile); stubs.append(pyfile)
                bdist_egg.write_stub(resource, pyfile)
        self.byte_compile(to_compile)   # compile .py's
        bdist_egg.write_safety_flag(os.path.join(egg_tmp,'EGG-INFO'),
            bdist_egg.analyze_egg(egg_tmp, stubs))  # write zip-safety flag

        for name in 'top_level','native_libs':
            if locals()[name]:
                txt = os.path.join(egg_tmp, 'EGG-INFO', name+'.txt')
                if not os.path.exists(txt):
                    f = open(txt,'w')
                    f.write('\n'.join(locals()[name])+'\n')
                    f.close()

    def check_conflicts(self, dist):
        """Verify that there are no conflicting "old-style" packages"""

        return dist     # XXX temporarily disable until new strategy is stable
        from imp import find_module, get_suffixes
        from glob import glob

        blockers = []
        names = dict.fromkeys(dist._get_metadata('top_level.txt')) # XXX private attr

        exts = {'.pyc':1, '.pyo':1}     # get_suffixes() might leave one out
        for ext,mode,typ in get_suffixes():
            exts[ext] = 1

        for path,files in expand_paths([self.install_dir]+self.all_site_dirs):
            for filename in files:
                base,ext = os.path.splitext(filename)
                if base in names:
                    if not ext:
                        # no extension, check for package
                        try:
                            f, filename, descr = find_module(base, [path])
                        except ImportError:
                            continue
                        else:
                            if f: f.close()
                            if filename not in blockers:
                                blockers.append(filename)
                    elif ext in exts and base!='site':  # XXX ugh
                        blockers.append(os.path.join(path,filename))
        if blockers:
            self.found_conflicts(dist, blockers)

        return dist

    def found_conflicts(self, dist, blockers):
        if self.delete_conflicting:
            log.warn("Attempting to delete conflicting packages:")
            return self.delete_blockers(blockers)

        msg = """\
-------------------------------------------------------------------------
CONFLICT WARNING:

The following modules or packages have the same names as modules or
packages being installed, and will be *before* the installed packages in
Python's search path.  You MUST remove all of the relevant files and
directories before you will be able to use the package(s) you are
installing:

   %s

""" % '\n   '.join(blockers)

        if self.ignore_conflicts_at_my_risk:
            msg += """\
(Note: you can run EasyInstall on '%s' with the
--delete-conflicting option to attempt deletion of the above files
and/or directories.)
""" % dist.project_name
        else:
            msg += """\
Note: you can attempt this installation again with EasyInstall, and use
either the --delete-conflicting (-D) option or the
--ignore-conflicts-at-my-risk option, to either delete the above files
and directories, or to ignore the conflicts, respectively.  Note that if
you ignore the conflicts, the installed package(s) may not work.
"""
        msg += """\
-------------------------------------------------------------------------
"""
        sys.stderr.write(msg)
        sys.stderr.flush()
        if not self.ignore_conflicts_at_my_risk:
            raise DistutilsError("Installation aborted due to conflicts")

    def installation_report(self, req, dist, what="Installed"):
        """Helpful installation message for display to package users"""
        msg = "\n%(what)s %(eggloc)s%(extras)s"
        if self.multi_version and not self.no_report:
            msg += """

Because this distribution was installed --multi-version, before you can
import modules from this package in an application, you will need to
'import pkg_resources' and then use a 'require()' call similar to one of
these examples, in order to select the desired version:

    pkg_resources.require("%(name)s")  # latest installed version
    pkg_resources.require("%(name)s==%(version)s")  # this exact version
    pkg_resources.require("%(name)s>=%(version)s")  # this version or higher
"""
            if self.install_dir not in map(normalize_path,sys.path):
                msg += """

Note also that the installation directory must be on sys.path at runtime for
this to work.  (e.g. by being the application's script directory, by being on
PYTHONPATH, or by being added to sys.path by your code.)
"""
        eggloc = dist.location
        name = dist.project_name
        version = dist.version
        extras = '' # TODO: self.report_extras(req, dist)
        return msg % locals()

    def report_editable(self, spec, setup_script):
        dirname = os.path.dirname(setup_script)
        python = sys.executable
        return """\nExtracted editable version of %(spec)s to %(dirname)s

If it uses setuptools in its setup script, you can activate it in
"development" mode by going to that directory and running::

    %(python)s setup.py develop

See the setuptools documentation for the "develop" command for more info.
""" % locals()

    def run_setup(self, setup_script, setup_base, args):
        sys.modules.setdefault('distutils.command.bdist_egg', bdist_egg)
        sys.modules.setdefault('distutils.command.egg_info', egg_info)

        args = list(args)
        if self.verbose>2:
            v = 'v' * (self.verbose - 1)
            args.insert(0,'-'+v)
        elif self.verbose<2:
            args.insert(0,'-q')
        if self.dry_run:
            args.insert(0,'-n')
        log.info(
            "Running %s %s", setup_script[len(setup_base)+1:], ' '.join(args)
        )
        try:
            run_setup(setup_script, args)
        except SystemExit, v:
            raise DistutilsError("Setup script exited with %s" % (v.args[0],))

    def build_and_install(self, setup_script, setup_base):
        args = ['bdist_egg', '--dist-dir']

        dist_dir = tempfile.mkdtemp(
            prefix='egg-dist-tmp-', dir=os.path.dirname(setup_script)
        )
        try:
            self._set_fetcher_options(os.path.dirname(setup_script))
            args.append(dist_dir)

            self.run_setup(setup_script, setup_base, args)
            all_eggs = Environment([dist_dir])
            eggs = []
            for key in all_eggs:
                for dist in all_eggs[key]:
                    eggs.append(self.install_egg(dist.location, setup_base))
            if not eggs and not self.dry_run:
                log.warn("No eggs found in %s (setup script problem?)",
                    dist_dir)
            return eggs
        finally:
            rmtree(dist_dir)
            log.set_verbosity(self.verbose) # restore our log verbosity

    def _set_fetcher_options(self, base):
        """
        When easy_install is about to run bdist_egg on a source dist, that
        source dist might have 'setup_requires' directives, requiring
        additional fetching. Ensure the fetcher options given to easy_install
        are available to that command as well.
        """
        # find the fetch options from easy_install and write them out
        #  to the setup.cfg file.
        ei_opts = self.distribution.get_option_dict('easy_install').copy()
        fetch_directives = (
            'find_links', 'site_dirs', 'index_url', 'optimize',
            'site_dirs', 'allow_hosts',
        )
        fetch_options = {}
        for key, val in ei_opts.iteritems():
            if key not in fetch_directives: continue
            fetch_options[key.replace('_', '-')] = val[1]
        # create a settings dictionary suitable for `edit_config`
        settings = dict(easy_install=fetch_options)
        cfg_filename = os.path.join(base, 'setup.cfg')
        setopt.edit_config(cfg_filename, settings)


    def update_pth(self,dist):
        if self.pth_file is None:
            return

        for d in self.pth_file[dist.key]:    # drop old entries
            if self.multi_version or d.location != dist.location:
                log.info("Removing %s from easy-install.pth file", d)
                self.pth_file.remove(d)
                if d.location in self.shadow_path:
                    self.shadow_path.remove(d.location)

        if not self.multi_version:
            if dist.location in self.pth_file.paths:
                log.info(
                    "%s is already the active version in easy-install.pth",
                    dist
                )
            else:
                log.info("Adding %s to easy-install.pth file", dist)
                self.pth_file.add(dist) # add new entry
                if dist.location not in self.shadow_path:
                    self.shadow_path.append(dist.location)

        if not self.dry_run:

            self.pth_file.save()
            if dist.key=='distribute':
                # Ensure that setuptools itself never becomes unavailable!
                # XXX should this check for latest version?
                filename = os.path.join(self.install_dir,'setuptools.pth')
                if os.path.islink(filename): os.unlink(filename)
                f = open(filename, 'wt')
                f.write(self.pth_file.make_relative(dist.location)+'\n')
                f.close()

    def unpack_progress(self, src, dst):
        # Progress filter for unpacking
        log.debug("Unpacking %s to %s", src, dst)
        return dst     # only unpack-and-compile skips files for dry run

    def unpack_and_compile(self, egg_path, destination):
        to_compile = []; to_chmod = []

        def pf(src,dst):
            if dst.endswith('.py') and not src.startswith('EGG-INFO/'):
                to_compile.append(dst)
                to_chmod.append(dst)
            elif dst.endswith('.dll') or dst.endswith('.so'):
                to_chmod.append(dst)
            self.unpack_progress(src,dst)
            return not self.dry_run and dst or None

        unpack_archive(egg_path, destination, pf)
        self.byte_compile(to_compile)
        if not self.dry_run:
            for f in to_chmod:
                mode = ((os.stat(f)[stat.ST_MODE]) | 0555) & 07755
                chmod(f, mode)

    def byte_compile(self, to_compile):
        if _dont_write_bytecode:
            self.warn('byte-compiling is disabled, skipping.')
            return

        from distutils.util import byte_compile
        try:
            # try to make the byte compile messages quieter
            log.set_verbosity(self.verbose - 1)

            byte_compile(to_compile, optimize=0, force=1, dry_run=self.dry_run)
            if self.optimize:
                byte_compile(
                    to_compile, optimize=self.optimize, force=1,
                    dry_run=self.dry_run
                )
        finally:
            log.set_verbosity(self.verbose)     # restore original verbosity








    def no_default_version_msg(self):
        return """bad install directory or PYTHONPATH

You are attempting to install a package to a directory that is not
on PYTHONPATH and which Python does not read ".pth" files from.  The
installation directory you specified (via --install-dir, --prefix, or
the distutils default setting) was:

    %s

and your PYTHONPATH environment variable currently contains:

    %r

Here are some of your options for correcting the problem:

* You can choose a different installation directory, i.e., one that is
  on PYTHONPATH or supports .pth files

* You can add the installation directory to the PYTHONPATH environment
  variable.  (It must then also be on PYTHONPATH whenever you run
  Python and want to use the package(s) you are installing.)

* You can set up the installation directory to support ".pth" files by
  using one of the approaches described here:

  http://packages.python.org/distribute/easy_install.html#custom-installation-locations

Please make the appropriate changes for your system and try again.""" % (
        self.install_dir, os.environ.get('PYTHONPATH','')
    )










    def install_site_py(self):
        """Make sure there's a site.py in the target dir, if needed"""

        if self.sitepy_installed:
            return  # already did it, or don't need to

        sitepy = os.path.join(self.install_dir, "site.py")
        source = resource_string(Requirement.parse("distribute"), "site.py")
        current = ""

        if os.path.exists(sitepy):
            log.debug("Checking existing site.py in %s", self.install_dir)
            f = open(sitepy,'rb')
            current = f.read()
            # we want str, not bytes
            if sys.version_info >= (3,):
                current = current.decode()

            f.close()
            if not current.startswith('def __boot():'):
                raise DistutilsError(
                    "%s is not a setuptools-generated site.py; please"
                    " remove it." % sitepy
                )

        if current != source:
            log.info("Creating %s", sitepy)
            if not self.dry_run:
                ensure_directory(sitepy)
                f = open(sitepy,'wb')
                f.write(source)
                f.close()
            self.byte_compile([sitepy])

        self.sitepy_installed = True




    def create_home_path(self):
        """Create directories under ~."""
        if not self.user:
            return
        home = convert_path(os.path.expanduser("~"))
        for name, path in self.config_vars.iteritems():
            if path.startswith(home) and not os.path.isdir(path):
                self.debug_print("os.makedirs('%s', 0700)" % path)
                os.makedirs(path, 0700)







    INSTALL_SCHEMES = dict(
        posix = dict(
            install_dir = '$base/lib/python$py_version_short/site-packages',
            script_dir  = '$base/bin',
        ),
    )

    DEFAULT_SCHEME = dict(
        install_dir = '$base/Lib/site-packages',
        script_dir  = '$base/Scripts',
    )

    def _expand(self, *attrs):
        config_vars = self.get_finalized_command('install').config_vars

        if self.prefix:
            # Set default install_dir/scripts from --prefix
            config_vars = config_vars.copy()
            config_vars['base'] = self.prefix
            scheme = self.INSTALL_SCHEMES.get(os.name,self.DEFAULT_SCHEME)
            for attr,val in scheme.items():
                if getattr(self,attr,None) is None:
                    setattr(self,attr,val)

        from distutils.util import subst_vars
        for attr in attrs:
            val = getattr(self, attr)
            if val is not None:
                val = subst_vars(val, config_vars)
                if os.name == 'posix':
                    val = os.path.expanduser(val)
                setattr(self, attr, val)









def get_site_dirs():
    # return a list of 'site' dirs
    sitedirs = filter(None,os.environ.get('PYTHONPATH','').split(os.pathsep))
    prefixes = [sys.prefix]
    if sys.exec_prefix != sys.prefix:
        prefixes.append(sys.exec_prefix)
    for prefix in prefixes:
        if prefix:
            if sys.platform in ('os2emx', 'riscos'):
                sitedirs.append(os.path.join(prefix, "Lib", "site-packages"))
            elif os.sep == '/':
                sitedirs.extend([os.path.join(prefix,
                                         "lib",
                                         "python" + sys.version[:3],
                                         "site-packages"),
                            os.path.join(prefix, "lib", "site-python")])
            else:
                sitedirs.extend(
                    [prefix, os.path.join(prefix, "lib", "site-packages")]
                )
            if sys.platform == 'darwin':
                # for framework builds *only* we add the standard Apple
                # locations. Currently only per-user, but /Library and
                # /Network/Library could be added too
                if 'Python.framework' in prefix:
                    home = os.environ.get('HOME')
                    if home:
                        sitedirs.append(
                            os.path.join(home,
                                         'Library',
                                         'Python',
                                         sys.version[:3],
                                         'site-packages'))
    for plat_specific in (0,1):
        site_lib = get_python_lib(plat_specific)
        if site_lib not in sitedirs: sitedirs.append(site_lib)

    if HAS_USER_SITE:
        sitedirs.append(site.USER_SITE)

    sitedirs = map(normalize_path, sitedirs)

    return sitedirs


def expand_paths(inputs):
    """Yield sys.path directories that might contain "old-style" packages"""

    seen = {}

    for dirname in inputs:
        dirname = normalize_path(dirname)
        if dirname in seen:
            continue

        seen[dirname] = 1
        if not os.path.isdir(dirname):
            continue

        files = os.listdir(dirname)
        yield dirname, files

        for name in files:
            if not name.endswith('.pth'):
                # We only care about the .pth files
                continue
            if name in ('easy-install.pth','setuptools.pth'):
                # Ignore .pth files that we control
                continue

            # Read the .pth file
            f = open(os.path.join(dirname,name))
            lines = list(yield_lines(f))
            f.close()

            # Yield existing non-dupe, non-import directory lines from it
            for line in lines:
                if not line.startswith("import"):
                    line = normalize_path(line.rstrip())
                    if line not in seen:
                        seen[line] = 1
                        if not os.path.isdir(line):
                            continue
                        yield line, os.listdir(line)


def extract_wininst_cfg(dist_filename):
    """Extract configuration data from a bdist_wininst .exe

    Returns a ConfigParser.RawConfigParser, or None
    """
    f = open(dist_filename,'rb')
    try:
        endrec = zipfile._EndRecData(f)
        if endrec is None:
            return None

        prepended = (endrec[9] - endrec[5]) - endrec[6]
        if prepended < 12:  # no wininst data here
            return None
        f.seek(prepended-12)

        import struct, StringIO, ConfigParser
        tag, cfglen, bmlen = struct.unpack("<iii",f.read(12))
        if tag not in (0x1234567A, 0x1234567B):
            return None     # not a valid tag

        f.seek(prepended-(12+cfglen))
        cfg = ConfigParser.RawConfigParser({'version':'','target_version':''})
        try:
            part = f.read(cfglen)
            # part is in bytes, but we need to read up to the first null
            #  byte.
            if sys.version_info >= (2,6):
                null_byte = bytes([0])
            else:
                null_byte = chr(0)
            config = part.split(null_byte, 1)[0]
            # Now the config is in bytes, but on Python 3, it must be
            #  unicode for the RawConfigParser, so decode it. Is this the
            #  right encoding?
            config = config.decode('ascii')
            cfg.readfp(StringIO.StringIO(config))
        except ConfigParser.Error:
            return None
        if not cfg.has_section('metadata') or not cfg.has_section('Setup'):
            return None
        return cfg

    finally:
        f.close()








def get_exe_prefixes(exe_filename):
    """Get exe->egg path translations for a given .exe file"""

    prefixes = [
        ('PURELIB/', ''), ('PLATLIB/pywin32_system32', ''),
        ('PLATLIB/', ''),
        ('SCRIPTS/', 'EGG-INFO/scripts/'),
        ('DATA/LIB/site-packages', ''),
    ]
    z = zipfile.ZipFile(exe_filename)
    try:
        for info in z.infolist():
            name = info.filename
            parts = name.split('/')
            if len(parts)==3 and parts[2]=='PKG-INFO':
                if parts[1].endswith('.egg-info'):
                    prefixes.insert(0,('/'.join(parts[:2]), 'EGG-INFO/'))
                    break
            if len(parts)<>2 or not name.endswith('.pth'):
                continue
            if name.endswith('-nspkg.pth'):
                continue
            if parts[0].upper() in ('PURELIB','PLATLIB'):
                for pth in yield_lines(z.read(name)):
                    pth = pth.strip().replace('\\','/')
                    if not pth.startswith('import'):
                        prefixes.append((('%s/%s/' % (parts[0],pth)), ''))
    finally:
        z.close()
    prefixes = [(x.lower(),y) for x, y in prefixes]
    prefixes.sort(); prefixes.reverse()
    return prefixes


def parse_requirement_arg(spec):
    try:
        return Requirement.parse(spec)
    except ValueError:
        raise DistutilsError(
            "Not a URL, existing file, or requirement spec: %r" % (spec,)
        )

class PthDistributions(Environment):
    """A .pth file with Distribution paths in it"""

    dirty = False

    def __init__(self, filename, sitedirs=()):
        self.filename = filename; self.sitedirs=map(normalize_path, sitedirs)
        self.basedir = normalize_path(os.path.dirname(self.filename))
        self._load(); Environment.__init__(self, [], None, None)
        for path in yield_lines(self.paths):
            map(self.add, find_distributions(path, True))

    def _load(self):
        self.paths = []
        saw_import = False
        seen = dict.fromkeys(self.sitedirs)
        if os.path.isfile(self.filename):
            f = open(self.filename,'rt')
            for line in f:
                if line.startswith('import'):
                    saw_import = True
                    continue
                path = line.rstrip()
                self.paths.append(path)
                if not path.strip() or path.strip().startswith('#'):
                    continue
                # skip non-existent paths, in case somebody deleted a package
                # manually, and duplicate paths as well
                path = self.paths[-1] = normalize_path(
                    os.path.join(self.basedir,path)
                )
                if not os.path.exists(path) or path in seen:
                    self.paths.pop()    # skip it
                    self.dirty = True   # we cleaned up, so we're dirty now :)
                    continue
                seen[path] = 1
            f.close()

        if self.paths and not saw_import:
            self.dirty = True   # ensure anything we touch has import wrappers
        while self.paths and not self.paths[-1].strip():
            self.paths.pop()

    def save(self):
        """Write changed .pth file back to disk"""
        if not self.dirty:
            return

        data = '\n'.join(map(self.make_relative,self.paths))
        if data:
            log.debug("Saving %s", self.filename)
            data = (
                "import sys; sys.__plen = len(sys.path)\n"
                "%s\n"
                "import sys; new=sys.path[sys.__plen:];"
                " del sys.path[sys.__plen:];"
                " p=getattr(sys,'__egginsert',0); sys.path[p:p]=new;"
                " sys.__egginsert = p+len(new)\n"
            ) % data

            if os.path.islink(self.filename):
                os.unlink(self.filename)
            f = open(self.filename,'wt')
            f.write(data); f.close()

        elif os.path.exists(self.filename):
            log.debug("Deleting empty %s", self.filename)
            os.unlink(self.filename)

        self.dirty = False

    def add(self,dist):
        """Add `dist` to the distribution map"""
        if (dist.location not in self.paths and (
                dist.location not in self.sitedirs or
                dist.location == os.getcwd() #account for '.' being in PYTHONPATH
                )):
            self.paths.append(dist.location)
            self.dirty = True
        Environment.add(self,dist)

    def remove(self,dist):
        """Remove `dist` from the distribution map"""
        while dist.location in self.paths:
            self.paths.remove(dist.location); self.dirty = True
        Environment.remove(self,dist)


    def make_relative(self,path):
        npath, last = os.path.split(normalize_path(path))
        baselen = len(self.basedir)
        parts = [last]
        sep = os.altsep=='/' and '/' or os.sep
        while len(npath)>=baselen:
            if npath==self.basedir:
                parts.append(os.curdir)
                parts.reverse()
                return sep.join(parts)
            npath, last = os.path.split(npath)
            parts.append(last)
        else:
            return path

def get_script_header(script_text, executable=sys_executable, wininst=False):
    """Create a #! line, getting options (if any) from script_text"""
    from distutils.command.build_scripts import first_line_re

    # first_line_re in Python >=3.1.4 and >=3.2.1 is a bytes pattern.
    if not isinstance(first_line_re.pattern, str):
        first_line_re = re.compile(first_line_re.pattern.decode())

    first = (script_text+'\n').splitlines()[0]
    match = first_line_re.match(first)
    options = ''
    if match:
        options = match.group(1) or ''
        if options: options = ' '+options
    if wininst:
        executable = "python.exe"
    else:
        executable = nt_quote_arg(executable)
    hdr = "#!%(executable)s%(options)s\n" % locals()
    if not isascii(hdr):
        # Non-ascii path to sys.executable, use -x to prevent warnings
        if options:
            if options.strip().startswith('-'):
                options = ' -x'+options.strip()[1:]
            # else: punt, we can't do it, let the warning happen anyway
        else:
            options = ' -x'
    executable = fix_jython_executable(executable, options)
    hdr = "#!%(executable)s%(options)s\n" % locals()
    return hdr

def auto_chmod(func, arg, exc):
    if func is os.remove and os.name=='nt':
        chmod(arg, stat.S_IWRITE)
        return func(arg)
    exc = sys.exc_info()
    raise exc[0], (exc[1][0], exc[1][1] + (" %s %s" % (func,arg)))

def uncache_zipdir(path):
    """Ensure that the importer caches dont have stale info for `path`"""
    from zipimport import _zip_directory_cache as zdc
    _uncache(path, zdc)
    _uncache(path, sys.path_importer_cache)

def _uncache(path, cache):
    if path in cache:
        del cache[path]
    else:
        path = normalize_path(path)
        for p in cache:
            if normalize_path(p)==path:
                del cache[p]
                return

def is_python(text, filename='<string>'):
    "Is this string a valid Python script?"
    try:
        compile(text, filename, 'exec')
    except (SyntaxError, TypeError):
        return False
    else:
        return True

def is_sh(executable):
    """Determine if the specified executable is a .sh (contains a #! line)"""
    try:
        fp = open(executable)
        magic = fp.read(2)
        fp.close()
    except (OSError,IOError): return executable
    return magic == '#!'

def nt_quote_arg(arg):
    """Quote a command line argument according to Windows parsing rules"""

    result = []
    needquote = False
    nb = 0

    needquote = (" " in arg) or ("\t" in arg)
    if needquote:
        result.append('"')

    for c in arg:
        if c == '\\':
            nb += 1
        elif c == '"':
            # double preceding backslashes, then add a \"
            result.append('\\' * (nb*2) + '\\"')
            nb = 0
        else:
            if nb:
                result.append('\\' * nb)
                nb = 0
            result.append(c)

    if nb:
        result.append('\\' * nb)

    if needquote:
        result.append('\\' * nb)    # double the trailing backslashes
        result.append('"')

    return ''.join(result)









def is_python_script(script_text, filename):
    """Is this text, as a whole, a Python script? (as opposed to shell/bat/etc.
    """
    if filename.endswith('.py') or filename.endswith('.pyw'):
        return True     # extension says it's Python
    if is_python(script_text, filename):
        return True     # it's syntactically valid Python
    if script_text.startswith('#!'):
        # It begins with a '#!' line, so check if 'python' is in it somewhere
        return 'python' in script_text.splitlines()[0].lower()

    return False    # Not any Python I can recognize

try:
    from os import chmod as _chmod
except ImportError:
    # Jython compatibility
    def _chmod(*args): pass

def chmod(path, mode):
    log.debug("changing mode of %s to %o", path, mode)
    try:
        _chmod(path, mode)
    except os.error, e:
        log.debug("chmod failed: %s", e)

def fix_jython_executable(executable, options):
    if sys.platform.startswith('java') and is_sh(executable):
        # Workaround Jython's sys.executable being a .sh (an invalid
        # shebang line interpreter)
        if options:
            # Can't apply the workaround, leave it broken
            log.warn("WARNING: Unable to adapt shebang line for Jython,"
                             " the following script is NOT executable\n"
                     "         see http://bugs.jython.org/issue1112 for"
                             " more information.")
        else:
            return '/usr/bin/env %s' % executable
    return executable


def get_script_args(dist, executable=sys_executable, wininst=False):
    """Yield write_script() argument tuples for a distribution's entrypoints"""
    spec = str(dist.as_requirement())
    header = get_script_header("", executable, wininst)
    for group in 'console_scripts', 'gui_scripts':
        for name, ep in dist.get_entry_map(group).items():
            script_text = (
                "# EASY-INSTALL-ENTRY-SCRIPT: %(spec)r,%(group)r,%(name)r\n"
                "__requires__ = %(spec)r\n"
                "import sys\n"
                "from pkg_resources import load_entry_point\n"
                "\n"
                "if __name__ == '__main__':"
                "\n"
                "    sys.exit(\n"
                "        load_entry_point(%(spec)r, %(group)r, %(name)r)()\n"
                "    )\n"
            ) % locals()
            if sys.platform=='win32' or wininst:
                # On Windows/wininst, add a .py extension and an .exe launcher
                if group=='gui_scripts':
                    ext, launcher = '-script.pyw', 'gui.exe'
                    old = ['.pyw']
                    new_header = re.sub('(?i)python.exe','pythonw.exe',header)
                else:
                    ext, launcher = '-script.py', 'cli.exe'
                    old = ['.py','.pyc','.pyo']
                    new_header = re.sub('(?i)pythonw.exe','python.exe',header)
                if is_64bit():
                    launcher = launcher.replace(".", "-64.")
                else:
                    launcher = launcher.replace(".", "-32.")
                if os.path.exists(new_header[2:-1]) or sys.platform!='win32':
                    hdr = new_header
                else:
                    hdr = header
                yield (name+ext, hdr+script_text, 't', [name+x for x in old])
                yield (
                    name+'.exe', resource_string('setuptools', launcher),
                    'b' # write in binary mode
                )
            else:
                # On other platforms, we assume the right thing to do is to
                # just write the stub with no extension.
                yield (name, header+script_text)

def rmtree(path, ignore_errors=False, onerror=auto_chmod):
    """Recursively delete a directory tree.

    This code is taken from the Python 2.4 version of 'shutil', because
    the 2.3 version doesn't really work right.
    """
    if ignore_errors:
        def onerror(*args):
            pass
    elif onerror is None:
        def onerror(*args):
            raise
    names = []
    try:
        names = os.listdir(path)
    except os.error, err:
        onerror(os.listdir, path, sys.exc_info())
    for name in names:
        fullname = os.path.join(path, name)
        try:
            mode = os.lstat(fullname).st_mode
        except os.error:
            mode = 0
        if stat.S_ISDIR(mode):
            rmtree(fullname, ignore_errors, onerror)
        else:
            try:
                os.remove(fullname)
            except os.error, err:
                onerror(os.remove, fullname, sys.exc_info())
    try:
        os.rmdir(path)
    except os.error:
        onerror(os.rmdir, path, sys.exc_info())

def current_umask():
    tmp = os.umask(022)
    os.umask(tmp)
    return tmp

def bootstrap():
    # This function is called when setuptools*.egg is run using /bin/sh
    import setuptools; argv0 = os.path.dirname(setuptools.__path__[0])
    sys.argv[0] = argv0; sys.argv.append(argv0); main()

def main(argv=None, **kw):
    from setuptools import setup
    from setuptools.dist import Distribution
    import distutils.core

    USAGE = """\
usage: %(script)s [options] requirement_or_url ...
   or: %(script)s --help
"""

    def gen_usage (script_name):
        script = os.path.basename(script_name)
        return USAGE % vars()

    def with_ei_usage(f):
        old_gen_usage = distutils.core.gen_usage
        try:
            distutils.core.gen_usage = gen_usage
            return f()
        finally:
            distutils.core.gen_usage = old_gen_usage

    class DistributionWithoutHelpCommands(Distribution):
        common_usage = ""

        def _show_help(self,*args,**kw):
            with_ei_usage(lambda: Distribution._show_help(self,*args,**kw))

        def find_config_files(self):
            files = Distribution.find_config_files(self)
            if 'setup.cfg' in files:
                files.remove('setup.cfg')
            return files

    if argv is None:
        argv = sys.argv[1:]

    with_ei_usage(lambda:
        setup(
            script_args = ['-q','easy_install', '-v']+argv,
            script_name = sys.argv[0] or 'easy_install',
            distclass=DistributionWithoutHelpCommands, **kw
        )
    )