#!/usr/bin/env python
"""Create a "virtual" Python installation"""

# fmt: off
import os  # isort:skip
import sys  # isort:skip

# If we are running in a new interpreter to create a virtualenv,
# we do NOT want paths from our existing location interfering with anything,
# So we remove this file's directory from sys.path - most likely to be
# the previous interpreter's site-packages. Solves #705, #763, #779
if os.environ.get("VIRTUALENV_INTERPRETER_RUNNING"):
    for path in sys.path[:]:
        if os.path.realpath(os.path.dirname(__file__)) == os.path.realpath(path):
            sys.path.remove(path)
# fmt: on

import base64
import codecs
import distutils.spawn
import distutils.sysconfig
import errno
import glob
import logging
import optparse
import os
import re
import shutil
import struct
import subprocess
import sys
import textwrap
import zlib
from distutils.util import strtobool
from os.path import join

try:
    import ConfigParser
except ImportError:
    import configparser as ConfigParser

__version__ = "16.1.0"
virtualenv_version = __version__  # legacy

if sys.version_info < (2, 7):
    print("ERROR: %s" % sys.exc_info()[1])
    print("ERROR: this script requires Python 2.7 or greater.")
    sys.exit(101)

try:
    basestring
except NameError:
    basestring = str

py_version = "python{}.{}".format(sys.version_info[0], sys.version_info[1])

is_jython = sys.platform.startswith("java")
is_pypy = hasattr(sys, "pypy_version_info")
is_win = sys.platform == "win32"
is_cygwin = sys.platform == "cygwin"
is_darwin = sys.platform == "darwin"
abiflags = getattr(sys, "abiflags", "")

user_dir = os.path.expanduser("~")
if is_win:
    default_storage_dir = os.path.join(user_dir, "virtualenv")
else:
    default_storage_dir = os.path.join(user_dir, ".virtualenv")
default_config_file = os.path.join(default_storage_dir, "virtualenv.ini")

if is_pypy:
    expected_exe = "pypy"
elif is_jython:
    expected_exe = "jython"
else:
    expected_exe = "python"

# Return a mapping of version -> Python executable
# Only provided for Windows, where the information in the registry is used
if not is_win:

    def get_installed_pythons():
        return {}


else:
    try:
        import winreg
    except ImportError:
        import _winreg as winreg

    def get_installed_pythons():
        exes = dict()
        # If both system and current user installations are found for a
        # particular Python version, the current user one is used
        for key in (winreg.HKEY_LOCAL_MACHINE, winreg.HKEY_CURRENT_USER):
            try:
                python_core = winreg.CreateKey(key, "Software\\Python\\PythonCore")
            except WindowsError:
                # No registered Python installations
                continue
            i = 0
            while True:
                try:
                    version = winreg.EnumKey(python_core, i)
                    i += 1
                    try:
                        path = winreg.QueryValue(python_core, "%s\\InstallPath" % version)
                    except WindowsError:
                        continue
                    exes[version] = join(path, "python.exe")
                except WindowsError:
                    break
            winreg.CloseKey(python_core)

        # For versions that track separate 32-bit (`X.Y-32`) & 64-bit (`X-Y`)
        # installation registrations, add a `X.Y-64` version tag and make the
        # extensionless `X.Y` version tag represent the 64-bit installation if
        # available or 32-bit if it is not
        updated = {}
        for ver in exes:
            if ver < "3.5":
                continue
            if ver.endswith("-32"):
                base_ver = ver[:-3]
                if base_ver not in exes:
                    updated[base_ver] = exes[ver]
            else:
                updated[ver + "-64"] = exes[ver]
        exes.update(updated)

        # Add the major versions
        # Sort the keys, then repeatedly update the major version entry
        # Last executable (i.e., highest version) wins with this approach,
        # 64-bit over 32-bit if both are found
        for ver in sorted(exes):
            exes[ver[0]] = exes[ver]

        return exes


REQUIRED_MODULES = [
    "os",
    "posix",
    "posixpath",
    "nt",
    "ntpath",
    "genericpath",
    "fnmatch",
    "locale",
    "encodings",
    "codecs",
    "stat",
    "UserDict",
    "readline",
    "copy_reg",
    "types",
    "re",
    "sre",
    "sre_parse",
    "sre_constants",
    "sre_compile",
    "zlib",
]

REQUIRED_FILES = ["lib-dynload", "config"]

majver, minver = sys.version_info[:2]
if majver == 2:
    if minver >= 6:
        REQUIRED_MODULES.extend(["warnings", "linecache", "_abcoll", "abc"])
    if minver >= 7:
        REQUIRED_MODULES.extend(["_weakrefset"])
elif majver == 3:
    # Some extra modules are needed for Python 3, but different ones
    # for different versions.
    REQUIRED_MODULES.extend(
        [
            "_abcoll",
            "warnings",
            "linecache",
            "abc",
            "io",
            "_weakrefset",
            "copyreg",
            "tempfile",
            "random",
            "__future__",
            "collections",
            "keyword",
            "tarfile",
            "shutil",
            "struct",
            "copy",
            "tokenize",
            "token",
            "functools",
            "heapq",
            "bisect",
            "weakref",
            "reprlib",
        ]
    )
    if minver >= 2:
        REQUIRED_FILES[-1] = "config-%s" % majver
    if minver >= 3:
        import sysconfig

        platdir = sysconfig.get_config_var("PLATDIR")
        REQUIRED_FILES.append(platdir)
        REQUIRED_MODULES.extend(["base64", "_dummy_thread", "hashlib", "hmac", "imp", "importlib", "rlcompleter"])
    if minver >= 4:
        REQUIRED_MODULES.extend(["operator", "_collections_abc", "_bootlocale"])
    if minver >= 6:
        REQUIRED_MODULES.extend(["enum"])

if is_pypy:
    # these are needed to correctly display the exceptions that may happen
    # during the bootstrap
    REQUIRED_MODULES.extend(["traceback", "linecache"])

    if majver == 3:
        # _functools is needed to import locale during stdio initialization and
        # needs to be copied on PyPy because it's not built in
        REQUIRED_MODULES.append("_functools")


class Logger(object):

    """
    Logging object for use in command-line script.  Allows ranges of
    levels, to avoid some redundancy of displayed information.
    """

    DEBUG = logging.DEBUG
    INFO = logging.INFO
    NOTIFY = (logging.INFO + logging.WARN) / 2
    WARN = WARNING = logging.WARN
    ERROR = logging.ERROR
    FATAL = logging.FATAL

    LEVELS = [DEBUG, INFO, NOTIFY, WARN, ERROR, FATAL]

    def __init__(self, consumers):
        self.consumers = consumers
        self.indent = 0
        self.in_progress = None
        self.in_progress_hanging = False

    def debug(self, msg, *args, **kw):
        self.log(self.DEBUG, msg, *args, **kw)

    def info(self, msg, *args, **kw):
        self.log(self.INFO, msg, *args, **kw)

    def notify(self, msg, *args, **kw):
        self.log(self.NOTIFY, msg, *args, **kw)

    def warn(self, msg, *args, **kw):
        self.log(self.WARN, msg, *args, **kw)

    def error(self, msg, *args, **kw):
        self.log(self.ERROR, msg, *args, **kw)

    def fatal(self, msg, *args, **kw):
        self.log(self.FATAL, msg, *args, **kw)

    def log(self, level, msg, *args, **kw):
        if args:
            if kw:
                raise TypeError("You may give positional or keyword arguments, not both")
        args = args or kw
        rendered = None
        for consumer_level, consumer in self.consumers:
            if self.level_matches(level, consumer_level):
                if self.in_progress_hanging and consumer in (sys.stdout, sys.stderr):
                    self.in_progress_hanging = False
                    print("")
                    sys.stdout.flush()
                if rendered is None:
                    if args:
                        rendered = msg % args
                    else:
                        rendered = msg
                    rendered = " " * self.indent + rendered
                if hasattr(consumer, "write"):
                    consumer.write(rendered + "\n")
                else:
                    consumer(rendered)

    def start_progress(self, msg):
        assert not self.in_progress, "Tried to start_progress({!r}) while in_progress {!r}".format(
            msg, self.in_progress
        )
        if self.level_matches(self.NOTIFY, self._stdout_level()):
            print(msg)
            sys.stdout.flush()
            self.in_progress_hanging = True
        else:
            self.in_progress_hanging = False
        self.in_progress = msg

    def end_progress(self, msg="done."):
        assert self.in_progress, "Tried to end_progress without start_progress"
        if self.stdout_level_matches(self.NOTIFY):
            if not self.in_progress_hanging:
                # Some message has been printed out since start_progress
                print("...{}{}".format(self.in_progress, msg))
                sys.stdout.flush()
            else:
                print(msg)
                sys.stdout.flush()
        self.in_progress = None
        self.in_progress_hanging = False

    def show_progress(self):
        """If we are in a progress scope, and no log messages have been
        shown, write out another '.'"""
        if self.in_progress_hanging:
            print(".")
            sys.stdout.flush()

    def stdout_level_matches(self, level):
        """Returns true if a message at this level will go to stdout"""
        return self.level_matches(level, self._stdout_level())

    def _stdout_level(self):
        """Returns the level that stdout runs at"""
        for level, consumer in self.consumers:
            if consumer is sys.stdout:
                return level
        return self.FATAL

    def level_matches(self, level, consumer_level):
        """
        >>> l = Logger([])
        >>> l.level_matches(3, 4)
        False
        >>> l.level_matches(3, 2)
        True
        >>> l.level_matches(slice(None, 3), 3)
        False
        >>> l.level_matches(slice(None, 3), 2)
        True
        >>> l.level_matches(slice(1, 3), 1)
        True
        >>> l.level_matches(slice(2, 3), 1)
        False
        """
        if isinstance(level, slice):
            start, stop = level.start, level.stop
            if start is not None and start > consumer_level:
                return False
            if stop is not None and stop <= consumer_level:
                return False
            return True
        else:
            return level >= consumer_level

    @classmethod
    def level_for_integer(cls, level):
        levels = cls.LEVELS
        if level < 0:
            return levels[0]
        if level >= len(levels):
            return levels[-1]
        return levels[level]


# create a silent logger just to prevent this from being undefined
# will be overridden with requested verbosity main() is called.
logger = Logger([(Logger.LEVELS[-1], sys.stdout)])


def mkdir(path):
    if not os.path.exists(path):
        logger.info("Creating %s", path)
        os.makedirs(path)
    else:
        logger.info("Directory %s already exists", path)


def copyfileordir(src, dest, symlink=True):
    if os.path.isdir(src):
        shutil.copytree(src, dest, symlink)
    else:
        shutil.copy2(src, dest)


def copyfile(src, dest, symlink=True):
    if not os.path.exists(src):
        # Some bad symlink in the src
        logger.warn("Cannot find file %s (bad symlink)", src)
        return
    if os.path.exists(dest):
        logger.debug("File %s already exists", dest)
        return
    if not os.path.exists(os.path.dirname(dest)):
        logger.info("Creating parent directories for %s", os.path.dirname(dest))
        os.makedirs(os.path.dirname(dest))
    if not os.path.islink(src):
        srcpath = os.path.abspath(src)
    else:
        srcpath = os.readlink(src)
    if symlink and hasattr(os, "symlink") and not is_win:
        logger.info("Symlinking %s", dest)
        try:
            os.symlink(srcpath, dest)
        except (OSError, NotImplementedError):
            logger.info("Symlinking failed, copying to %s", dest)
            copyfileordir(src, dest, symlink)
    else:
        logger.info("Copying to %s", dest)
        copyfileordir(src, dest, symlink)


def writefile(dest, content, overwrite=True):
    if not os.path.exists(dest):
        logger.info("Writing %s", dest)
        with open(dest, "wb") as f:
            f.write(content.encode("utf-8"))
        return
    else:
        with open(dest, "rb") as f:
            c = f.read()
        if c != content.encode("utf-8"):
            if not overwrite:
                logger.notify("File %s exists with different content; not overwriting", dest)
                return
            logger.notify("Overwriting %s with new content", dest)
            with open(dest, "wb") as f:
                f.write(content.encode("utf-8"))
        else:
            logger.info("Content %s already in place", dest)


def rmtree(dir):
    if os.path.exists(dir):
        logger.notify("Deleting tree %s", dir)
        shutil.rmtree(dir)
    else:
        logger.info("Do not need to delete %s; already gone", dir)


def make_exe(fn):
    if hasattr(os, "chmod"):
        oldmode = os.stat(fn).st_mode & 0xFFF  # 0o7777
        newmode = (oldmode | 0x16D) & 0xFFF  # 0o555, 0o7777
        os.chmod(fn, newmode)
        logger.info("Changed mode of %s to %s", fn, oct(newmode))


def _find_file(filename, dirs):
    for dir in reversed(dirs):
        files = glob.glob(os.path.join(dir, filename))
        if files and os.path.isfile(files[0]):
            return True, files[0]
    return False, filename


def file_search_dirs():
    here = os.path.dirname(os.path.abspath(__file__))
    dirs = [here, join(here, "virtualenv_support")]
    if os.path.splitext(os.path.dirname(__file__))[0] != "virtualenv":
        # Probably some boot script; just in case virtualenv is installed...
        try:
            import virtualenv
        except ImportError:
            pass
        else:
            dirs.append(os.path.join(os.path.dirname(virtualenv.__file__), "virtualenv_support"))
    return [d for d in dirs if os.path.isdir(d)]


class UpdatingDefaultsHelpFormatter(optparse.IndentedHelpFormatter):
    """
    Custom help formatter for use in ConfigOptionParser that updates
    the defaults before expanding them, allowing them to show up correctly
    in the help listing
    """

    def expand_default(self, option):
        if self.parser is not None:
            self.parser.update_defaults(self.parser.defaults)
        return optparse.IndentedHelpFormatter.expand_default(self, option)


class ConfigOptionParser(optparse.OptionParser):
    """
    Custom option parser which updates its defaults by checking the
    configuration files and environmental variables
    """

    def __init__(self, *args, **kwargs):
        self.config = ConfigParser.RawConfigParser()
        self.files = self.get_config_files()
        self.config.read(self.files)
        optparse.OptionParser.__init__(self, *args, **kwargs)

    def get_config_files(self):
        config_file = os.environ.get("VIRTUALENV_CONFIG_FILE", False)
        if config_file and os.path.exists(config_file):
            return [config_file]
        return [default_config_file]

    def update_defaults(self, defaults):
        """
        Updates the given defaults with values from the config files and
        the environ. Does a little special handling for certain types of
        options (lists).
        """
        # Then go and look for the other sources of configuration:
        config = {}
        # 1. config files
        config.update(dict(self.get_config_section("virtualenv")))
        # 2. environmental variables
        config.update(dict(self.get_environ_vars()))
        # Then set the options with those values
        for key, val in config.items():
            key = key.replace("_", "-")
            if not key.startswith("--"):
                key = "--%s" % key  # only prefer long opts
            option = self.get_option(key)
            if option is not None:
                # ignore empty values
                if not val:
                    continue
                # handle multiline configs
                if option.action == "append":
                    val = val.split()
                else:
                    option.nargs = 1
                if option.action == "store_false":
                    val = not strtobool(val)
                elif option.action in ("store_true", "count"):
                    val = strtobool(val)
                try:
                    val = option.convert_value(key, val)
                except optparse.OptionValueError:
                    e = sys.exc_info()[1]
                    print("An error occurred during configuration: %s" % e)
                    sys.exit(3)
                defaults[option.dest] = val
        return defaults

    def get_config_section(self, name):
        """
        Get a section of a configuration
        """
        if self.config.has_section(name):
            return self.config.items(name)
        return []

    def get_environ_vars(self, prefix="VIRTUALENV_"):
        """
        Returns a generator with all environmental vars with prefix VIRTUALENV
        """
        for key, val in os.environ.items():
            if key.startswith(prefix):
                yield (key.replace(prefix, "").lower(), val)

    def get_default_values(self):
        """
        Overridding to make updating the defaults after instantiation of
        the option parser possible, update_defaults() does the dirty work.
        """
        if not self.process_default_values:
            # Old, pre-Optik 1.5 behaviour.
            return optparse.Values(self.defaults)

        defaults = self.update_defaults(self.defaults.copy())  # ours
        for option in self._get_all_options():
            default = defaults.get(option.dest)
            if isinstance(default, basestring):
                opt_str = option.get_opt_string()
                defaults[option.dest] = option.check_value(opt_str, default)
        return optparse.Values(defaults)


def main():
    parser = ConfigOptionParser(
        version=virtualenv_version, usage="%prog [OPTIONS] DEST_DIR", formatter=UpdatingDefaultsHelpFormatter()
    )

    parser.add_option("-v", "--verbose", action="count", dest="verbose", default=0, help="Increase verbosity.")

    parser.add_option("-q", "--quiet", action="count", dest="quiet", default=0, help="Decrease verbosity.")

    parser.add_option(
        "-p",
        "--python",
        dest="python",
        metavar="PYTHON_EXE",
        help="The Python interpreter to use, e.g., --python=python3.5 will use the python3.5 "
        "interpreter to create the new environment.  The default is the interpreter that "
        "virtualenv was installed with (%s)" % sys.executable,
    )

    parser.add_option(
        "--clear", dest="clear", action="store_true", help="Clear out the non-root install and start from scratch."
    )

    parser.set_defaults(system_site_packages=False)
    parser.add_option(
        "--no-site-packages",
        dest="system_site_packages",
        action="store_false",
        help="DEPRECATED. Retained only for backward compatibility. "
        "Not having access to global site-packages is now the default behavior.",
    )

    parser.add_option(
        "--system-site-packages",
        dest="system_site_packages",
        action="store_true",
        help="Give the virtual environment access to the global site-packages.",
    )

    parser.add_option(
        "--always-copy",
        dest="symlink",
        action="store_false",
        default=True,
        help="Always copy files rather than symlinking.",
    )

    parser.add_option(
        "--relocatable",
        dest="relocatable",
        action="store_true",
        help="Make an EXISTING virtualenv environment relocatable. "
        "This fixes up scripts and makes all .pth files relative.",
    )

    parser.add_option(
        "--no-setuptools",
        dest="no_setuptools",
        action="store_true",
        help="Do not install setuptools in the new virtualenv.",
    )

    parser.add_option("--no-pip", dest="no_pip", action="store_true", help="Do not install pip in the new virtualenv.")

    parser.add_option(
        "--no-wheel", dest="no_wheel", action="store_true", help="Do not install wheel in the new virtualenv."
    )

    default_search_dirs = file_search_dirs()
    parser.add_option(
        "--extra-search-dir",
        dest="search_dirs",
        action="append",
        metavar="DIR",
        default=default_search_dirs,
        help="Directory to look for setuptools/pip distributions in. " "This option can be used multiple times.",
    )

    parser.add_option(
        "--download",
        dest="download",
        default=True,
        action="store_true",
        help="Download preinstalled packages from PyPI.",
    )

    parser.add_option(
        "--no-download",
        "--never-download",
        dest="download",
        action="store_false",
        help="Do not download preinstalled packages from PyPI.",
    )

    parser.add_option("--prompt", dest="prompt", help="Provides an alternative prompt prefix for this environment.")

    parser.add_option(
        "--setuptools",
        dest="setuptools",
        action="store_true",
        help="DEPRECATED. Retained only for backward compatibility. This option has no effect.",
    )

    parser.add_option(
        "--distribute",
        dest="distribute",
        action="store_true",
        help="DEPRECATED. Retained only for backward compatibility. This option has no effect.",
    )

    parser.add_option(
        "--unzip-setuptools",
        action="store_true",
        help="DEPRECATED.  Retained only for backward compatibility. This option has no effect.",
    )

    if "extend_parser" in globals():
        extend_parser(parser)  # noqa: F821

    options, args = parser.parse_args()

    global logger

    if "adjust_options" in globals():
        adjust_options(options, args)  # noqa: F821

    verbosity = options.verbose - options.quiet
    logger = Logger([(Logger.level_for_integer(2 - verbosity), sys.stdout)])

    if options.python and not os.environ.get("VIRTUALENV_INTERPRETER_RUNNING"):
        env = os.environ.copy()
        interpreter = resolve_interpreter(options.python)
        if interpreter == sys.executable:
            logger.warn("Already using interpreter %s" % interpreter)
        else:
            logger.notify("Running virtualenv with interpreter %s" % interpreter)
            env["VIRTUALENV_INTERPRETER_RUNNING"] = "true"
            file = __file__
            if file.endswith(".pyc"):
                file = file[:-1]
            popen = subprocess.Popen([interpreter, file] + sys.argv[1:], env=env)
            raise SystemExit(popen.wait())

    if not args:
        print("You must provide a DEST_DIR")
        parser.print_help()
        sys.exit(2)
    if len(args) > 1:
        print("There must be only one argument: DEST_DIR (you gave %s)" % (" ".join(args)))
        parser.print_help()
        sys.exit(2)

    home_dir = args[0]

    if os.path.exists(home_dir) and os.path.isfile(home_dir):
        logger.fatal("ERROR: File already exists and is not a directory.")
        logger.fatal("Please provide a different path or delete the file.")
        sys.exit(3)

    if os.environ.get("WORKING_ENV"):
        logger.fatal("ERROR: you cannot run virtualenv while in a workingenv")
        logger.fatal("Please deactivate your workingenv, then re-run this script")
        sys.exit(3)

    if "PYTHONHOME" in os.environ:
        logger.warn("PYTHONHOME is set.  You *must* activate the virtualenv before using it")
        del os.environ["PYTHONHOME"]

    if options.relocatable:
        make_environment_relocatable(home_dir)
        return

    create_environment(
        home_dir,
        site_packages=options.system_site_packages,
        clear=options.clear,
        prompt=options.prompt,
        search_dirs=options.search_dirs,
        download=options.download,
        no_setuptools=options.no_setuptools,
        no_pip=options.no_pip,
        no_wheel=options.no_wheel,
        symlink=options.symlink,
    )
    if "after_install" in globals():
        after_install(options, home_dir)  # noqa: F821


def call_subprocess(
    cmd,
    show_stdout=True,
    filter_stdout=None,
    cwd=None,
    raise_on_returncode=True,
    extra_env=None,
    remove_from_env=None,
    stdin=None,
):
    cmd_parts = []
    for part in cmd:
        if len(part) > 45:
            part = part[:20] + "..." + part[-20:]
        if " " in part or "\n" in part or '"' in part or "'" in part:
            part = '"%s"' % part.replace('"', '\\"')
        if hasattr(part, "decode"):
            try:
                part = part.decode(sys.getdefaultencoding())
            except UnicodeDecodeError:
                part = part.decode(sys.getfilesystemencoding())
        cmd_parts.append(part)
    cmd_desc = " ".join(cmd_parts)
    if show_stdout:
        stdout = None
    else:
        stdout = subprocess.PIPE
    logger.debug("Running command %s" % cmd_desc)
    if extra_env or remove_from_env:
        env = os.environ.copy()
        if extra_env:
            env.update(extra_env)
        if remove_from_env:
            for varname in remove_from_env:
                env.pop(varname, None)
    else:
        env = None
    try:
        proc = subprocess.Popen(
            cmd,
            stderr=subprocess.STDOUT,
            stdin=None if stdin is None else subprocess.PIPE,
            stdout=stdout,
            cwd=cwd,
            env=env,
        )
    except Exception:
        e = sys.exc_info()[1]
        logger.fatal("Error {} while executing command {}".format(e, cmd_desc))
        raise
    all_output = []
    if stdout is not None:
        if stdin is not None:
            proc.stdin.write(stdin)
            proc.stdin.close()

        stdout = proc.stdout
        encoding = sys.getdefaultencoding()
        fs_encoding = sys.getfilesystemencoding()
        while 1:
            line = stdout.readline()
            try:
                line = line.decode(encoding)
            except UnicodeDecodeError:
                line = line.decode(fs_encoding)
            if not line:
                break
            line = line.rstrip()
            all_output.append(line)
            if filter_stdout:
                level = filter_stdout(line)
                if isinstance(level, tuple):
                    level, line = level
                logger.log(level, line)
                if not logger.stdout_level_matches(level):
                    logger.show_progress()
            else:
                logger.info(line)
    else:
        proc.communicate(stdin)
    proc.wait()
    if proc.returncode:
        if raise_on_returncode:
            if all_output:
                logger.notify("Complete output from command %s:" % cmd_desc)
                logger.notify("\n".join(all_output) + "\n----------------------------------------")
            raise OSError("Command {} failed with error code {}".format(cmd_desc, proc.returncode))
        else:
            logger.warn("Command {} had error code {}".format(cmd_desc, proc.returncode))


def filter_install_output(line):
    if line.strip().startswith("running"):
        return Logger.INFO
    return Logger.DEBUG


def find_wheels(projects, search_dirs):
    """Find wheels from which we can import PROJECTS.

    Scan through SEARCH_DIRS for a wheel for each PROJECT in turn. Return
    a list of the first wheel found for each PROJECT
    """

    wheels = []

    # Look through SEARCH_DIRS for the first suitable wheel. Don't bother
    # about version checking here, as this is simply to get something we can
    # then use to install the correct version.
    for project in projects:
        for dirname in search_dirs:
            # This relies on only having "universal" wheels available.
            # The pattern could be tightened to require -py2.py3-none-any.whl.
            files = glob.glob(os.path.join(dirname, project + "-*.whl"))
            if files:
                wheels.append(os.path.abspath(files[0]))
                break
        else:
            # We're out of luck, so quit with a suitable error
            logger.fatal("Cannot find a wheel for {}".format(project))

    return wheels


def install_wheel(project_names, py_executable, search_dirs=None, download=False):
    if search_dirs is None:
        search_dirs = file_search_dirs()

    wheels = find_wheels(["setuptools", "pip"], search_dirs)
    python_path = os.pathsep.join(wheels)

    # PIP_FIND_LINKS uses space as the path separator and thus cannot have paths
    # with spaces in them. Convert any of those to local file:// URL form.
    try:
        from urlparse import urljoin
        from urllib import pathname2url
    except ImportError:
        from urllib.parse import urljoin
        from urllib.request import pathname2url

    def space_path2url(p):
        if " " not in p:
            return p
        return urljoin("file:", pathname2url(os.path.abspath(p)))

    findlinks = " ".join(space_path2url(d) for d in search_dirs)
    SCRIPT = textwrap.dedent(
        """
        import sys
        import pkgutil
        import tempfile
        import os

        try:
            from pip._internal import main as _main
            cert_data = pkgutil.get_data("pip._vendor.certifi", "cacert.pem")
        except ImportError:
            from pip import main as _main
            cert_data = pkgutil.get_data("pip._vendor.requests", "cacert.pem")

        if cert_data is not None:
            cert_file = tempfile.NamedTemporaryFile(delete=False)
            cert_file.write(cert_data)
            cert_file.close()
        else:
            cert_file = None

        try:
            args = ["install", "--ignore-installed"]
            if cert_file is not None:
                args += ["--cert", cert_file.name{}]
            args += sys.argv[1:]

            sys.exit(_main(args))
        finally:
            if cert_file is not None:
                os.remove(cert_file.name)
    """.format(
            ", '--no-cache'" if is_jython else ""
        )
    ).encode("utf8")

    cmd = [py_executable, "-"] + project_names
    logger.start_progress("Installing %s..." % (", ".join(project_names)))
    logger.indent += 2

    env = {
        "PYTHONPATH": python_path,
        "JYTHONPATH": python_path,  # for Jython < 3.x
        "PIP_FIND_LINKS": findlinks,
        "PIP_USE_WHEEL": "1",
        "PIP_ONLY_BINARY": ":all:",
        "PIP_USER": "0",
        "PIP_NO_INPUT": "1",
    }

    if not download:
        env["PIP_NO_INDEX"] = "1"

    try:
        call_subprocess(cmd, show_stdout=False, extra_env=env, stdin=SCRIPT)
    finally:
        logger.indent -= 2
        logger.end_progress()


def create_environment(
    home_dir,
    site_packages=False,
    clear=False,
    prompt=None,
    search_dirs=None,
    download=False,
    no_setuptools=False,
    no_pip=False,
    no_wheel=False,
    symlink=True,
):
    """
    Creates a new environment in ``home_dir``.

    If ``site_packages`` is true, then the global ``site-packages/``
    directory will be on the path.

    If ``clear`` is true (default False) then the environment will
    first be cleared.
    """
    home_dir, lib_dir, inc_dir, bin_dir = path_locations(home_dir)

    py_executable = os.path.abspath(
        install_python(home_dir, lib_dir, inc_dir, bin_dir, site_packages=site_packages, clear=clear, symlink=symlink)
    )

    install_distutils(home_dir)

    to_install = []

    if not no_setuptools:
        to_install.append("setuptools")

    if not no_pip:
        to_install.append("pip")

    if not no_wheel:
        to_install.append("wheel")

    if to_install:
        install_wheel(to_install, py_executable, search_dirs, download=download)

    install_activate(home_dir, bin_dir, prompt)

    install_python_config(home_dir, bin_dir, prompt)


def is_executable_file(fpath):
    return os.path.isfile(fpath) and os.access(fpath, os.X_OK)


def path_locations(home_dir, dry_run=False):
    """Return the path locations for the environment (where libraries are,
    where scripts go, etc)"""
    home_dir = os.path.abspath(home_dir)
    # XXX: We'd use distutils.sysconfig.get_python_inc/lib but its
    # prefix arg is broken: http://bugs.python.org/issue3386
    if is_win:
        # Windows has lots of problems with executables with spaces in
        # the name; this function will remove them (using the ~1
        # format):
        if not dry_run:
            mkdir(home_dir)
        if " " in home_dir:
            import ctypes

            GetShortPathName = ctypes.windll.kernel32.GetShortPathNameW
            size = max(len(home_dir) + 1, 256)
            buf = ctypes.create_unicode_buffer(size)
            try:
                u = unicode
            except NameError:
                u = str
            ret = GetShortPathName(u(home_dir), buf, size)
            if not ret:
                print('Error: the path "%s" has a space in it' % home_dir)
                print("We could not determine the short pathname for it.")
                print("Exiting.")
                sys.exit(3)
            home_dir = str(buf.value)
        lib_dir = join(home_dir, "Lib")
        inc_dir = join(home_dir, "Include")
        bin_dir = join(home_dir, "Scripts")
    if is_jython:
        lib_dir = join(home_dir, "Lib")
        inc_dir = join(home_dir, "Include")
        bin_dir = join(home_dir, "bin")
    elif is_pypy:
        lib_dir = home_dir
        inc_dir = join(home_dir, "include")
        bin_dir = join(home_dir, "bin")
    elif not is_win:
        lib_dir = join(home_dir, "lib", py_version)
        inc_dir = join(home_dir, "include", py_version + abiflags)
        bin_dir = join(home_dir, "bin")
    return home_dir, lib_dir, inc_dir, bin_dir


def change_prefix(filename, dst_prefix):
    prefixes = [sys.prefix]

    if is_darwin:
        prefixes.extend(
            (
                os.path.join("/Library/Python", sys.version[:3], "site-packages"),
                os.path.join(sys.prefix, "Extras", "lib", "python"),
                os.path.join("~", "Library", "Python", sys.version[:3], "site-packages"),
                # Python 2.6 no-frameworks
                os.path.join("~", ".local", "lib", "python", sys.version[:3], "site-packages"),
                # System Python 2.7 on OSX Mountain Lion
                os.path.join("~", "Library", "Python", sys.version[:3], "lib", "python", "site-packages"),
            )
        )

    if hasattr(sys, "real_prefix"):
        prefixes.append(sys.real_prefix)
    if hasattr(sys, "base_prefix"):
        prefixes.append(sys.base_prefix)
    prefixes = list(map(os.path.expanduser, prefixes))
    prefixes = list(map(os.path.abspath, prefixes))
    # Check longer prefixes first so we don't split in the middle of a filename
    prefixes = sorted(prefixes, key=len, reverse=True)
    filename = os.path.abspath(filename)
    # On Windows, make sure drive letter is uppercase
    if is_win and filename[0] in "abcdefghijklmnopqrstuvwxyz":
        filename = filename[0].upper() + filename[1:]
    for i, prefix in enumerate(prefixes):
        if is_win and prefix[0] in "abcdefghijklmnopqrstuvwxyz":
            prefixes[i] = prefix[0].upper() + prefix[1:]
    for src_prefix in prefixes:
        if filename.startswith(src_prefix):
            _, relpath = filename.split(src_prefix, 1)
            if src_prefix != os.sep:  # sys.prefix == "/"
                assert relpath[0] == os.sep
                relpath = relpath[1:]
            return join(dst_prefix, relpath)
    assert False, "Filename {} does not start with any of these prefixes: {}".format(filename, prefixes)


def copy_required_modules(dst_prefix, symlink):
    import warnings

    with warnings.catch_warnings():
        # Ignore deprecation of the imp module
        # TODO: do not use deprecated imp module
        warnings.simplefilter("ignore")
        import imp

    for modname in REQUIRED_MODULES:
        if modname in sys.builtin_module_names:
            logger.info("Ignoring built-in bootstrap module: %s" % modname)
            continue
        try:
            f, filename, _ = imp.find_module(modname)
        except ImportError:
            logger.info("Cannot import bootstrap module: %s" % modname)
        else:
            if f is not None:
                f.close()
            # special-case custom readline.so on OS X, but not for pypy:
            if (
                modname == "readline"
                and sys.platform == "darwin"
                and not (is_pypy or filename.endswith(join("lib-dynload", "readline.so")))
            ):
                dst_filename = join(dst_prefix, "lib", "python%s" % sys.version[:3], "readline.so")
            elif modname == "readline" and sys.platform == "win32":
                # special-case for Windows, where readline is not a
                # standard module, though it may have been installed in
                # site-packages by a third-party package
                pass
            else:
                dst_filename = change_prefix(filename, dst_prefix)
            copyfile(filename, dst_filename, symlink)
            if filename.endswith(".pyc"):
                pyfile = filename[:-1]
                if os.path.exists(pyfile):
                    copyfile(pyfile, dst_filename[:-1], symlink)


def copy_tcltk(src, dest, symlink):
    """ copy tcl/tk libraries on Windows (issue #93) """
    for libversion in "8.5", "8.6":
        for libname in "tcl", "tk":
            srcdir = join(src, "tcl", libname + libversion)
            destdir = join(dest, "tcl", libname + libversion)
            # Only copy the dirs from the above combinations that exist
            if os.path.exists(srcdir) and not os.path.exists(destdir):
                copyfileordir(srcdir, destdir, symlink)


def subst_path(prefix_path, prefix, home_dir):
    prefix_path = os.path.normpath(prefix_path)
    prefix = os.path.normpath(prefix)
    home_dir = os.path.normpath(home_dir)
    if not prefix_path.startswith(prefix):
        logger.warn("Path not in prefix %r %r", prefix_path, prefix)
        return
    return prefix_path.replace(prefix, home_dir, 1)


def install_python(home_dir, lib_dir, inc_dir, bin_dir, site_packages, clear, symlink=True):
    """Install just the base environment, no distutils patches etc"""
    if sys.executable.startswith(bin_dir):
        print("Please use the *system* python to run this script")
        return

    if clear:
        rmtree(lib_dir)
        # FIXME: why not delete it?
        # Maybe it should delete everything with #!/path/to/venv/python in it
        logger.notify("Not deleting %s", bin_dir)

    if hasattr(sys, "real_prefix"):
        logger.notify("Using real prefix %r" % sys.real_prefix)
        prefix = sys.real_prefix
    elif hasattr(sys, "base_prefix"):
        logger.notify("Using base prefix %r" % sys.base_prefix)
        prefix = sys.base_prefix
    else:
        prefix = sys.prefix
    prefix = os.path.abspath(prefix)
    mkdir(lib_dir)
    fix_lib64(lib_dir, symlink)
    stdlib_dirs = [os.path.dirname(os.__file__)]
    if is_win:
        stdlib_dirs.append(join(os.path.dirname(stdlib_dirs[0]), "DLLs"))
    elif is_darwin:
        stdlib_dirs.append(join(stdlib_dirs[0], "site-packages"))
    if hasattr(os, "symlink"):
        logger.info("Symlinking Python bootstrap modules")
    else:
        logger.info("Copying Python bootstrap modules")
    logger.indent += 2
    try:
        # copy required files...
        for stdlib_dir in stdlib_dirs:
            if not os.path.isdir(stdlib_dir):
                continue
            for fn in os.listdir(stdlib_dir):
                bn = os.path.splitext(fn)[0]
                if fn != "site-packages" and bn in REQUIRED_FILES:
                    copyfile(join(stdlib_dir, fn), join(lib_dir, fn), symlink)
        # ...and modules
        copy_required_modules(home_dir, symlink)
    finally:
        logger.indent -= 2
    # ...copy tcl/tk
    if is_win:
        copy_tcltk(prefix, home_dir, symlink)
    mkdir(join(lib_dir, "site-packages"))
    import site

    site_filename = site.__file__
    if site_filename.endswith(".pyc") or site_filename.endswith(".pyo"):
        site_filename = site_filename[:-1]
    elif site_filename.endswith("$py.class"):
        site_filename = site_filename.replace("$py.class", ".py")
    site_filename_dst = change_prefix(site_filename, home_dir)
    site_dir = os.path.dirname(site_filename_dst)
    writefile(site_filename_dst, SITE_PY)
    writefile(join(site_dir, "orig-prefix.txt"), prefix)
    site_packages_filename = join(site_dir, "no-global-site-packages.txt")
    if not site_packages:
        writefile(site_packages_filename, "")

    if is_pypy or is_win:
        stdinc_dir = join(prefix, "include")
    else:
        stdinc_dir = join(prefix, "include", py_version + abiflags)
    if os.path.exists(stdinc_dir):
        copyfile(stdinc_dir, inc_dir, symlink)
    else:
        logger.debug("No include dir %s" % stdinc_dir)

    platinc_dir = distutils.sysconfig.get_python_inc(plat_specific=1)
    if platinc_dir != stdinc_dir:
        platinc_dest = distutils.sysconfig.get_python_inc(plat_specific=1, prefix=home_dir)
        if platinc_dir == platinc_dest:
            # Do platinc_dest manually due to a CPython bug;
            # not http://bugs.python.org/issue3386 but a close cousin
            platinc_dest = subst_path(platinc_dir, prefix, home_dir)
        if platinc_dest:
            # PyPy's stdinc_dir and prefix are relative to the original binary
            # (traversing virtualenvs), whereas the platinc_dir is relative to
            # the inner virtualenv and ignores the prefix argument.
            # This seems more evolved than designed.
            copyfile(platinc_dir, platinc_dest, symlink)

    # pypy never uses exec_prefix, just ignore it
    if sys.exec_prefix != prefix and not is_pypy:
        if is_win:
            exec_dir = join(sys.exec_prefix, "lib")
        elif is_jython:
            exec_dir = join(sys.exec_prefix, "Lib")
        else:
            exec_dir = join(sys.exec_prefix, "lib", py_version)
        if os.path.isdir(exec_dir):
            for fn in os.listdir(exec_dir):
                copyfile(join(exec_dir, fn), join(lib_dir, fn), symlink)

    if is_jython:
        # Jython has either jython-dev.jar and javalib/ dir, or just
        # jython.jar
        for name in "jython-dev.jar", "javalib", "jython.jar":
            src = join(prefix, name)
            if os.path.exists(src):
                copyfile(src, join(home_dir, name), symlink)
        # XXX: registry should always exist after Jython 2.5rc1
        src = join(prefix, "registry")
        if os.path.exists(src):
            copyfile(src, join(home_dir, "registry"), symlink=False)
        copyfile(join(prefix, "cachedir"), join(home_dir, "cachedir"), symlink=False)

    mkdir(bin_dir)
    py_executable = join(bin_dir, os.path.basename(sys.executable))
    if "Python.framework" in prefix:
        # OS X framework builds cause validation to break
        # https://github.com/pypa/virtualenv/issues/322
        if os.environ.get("__PYVENV_LAUNCHER__"):
            del os.environ["__PYVENV_LAUNCHER__"]
        if re.search(r"/Python(?:-32|-64)*$", py_executable):
            # The name of the python executable is not quite what
            # we want, rename it.
            py_executable = os.path.join(os.path.dirname(py_executable), "python")

    logger.notify("New %s executable in %s", expected_exe, py_executable)
    pcbuild_dir = os.path.dirname(sys.executable)
    pyd_pth = os.path.join(lib_dir, "site-packages", "virtualenv_builddir_pyd.pth")
    if is_win and os.path.exists(os.path.join(pcbuild_dir, "build.bat")):
        logger.notify("Detected python running from build directory %s", pcbuild_dir)
        logger.notify("Writing .pth file linking to build directory for *.pyd files")
        writefile(pyd_pth, pcbuild_dir)
    else:
        pcbuild_dir = None
        if os.path.exists(pyd_pth):
            logger.info("Deleting %s (not Windows env or not build directory python)" % pyd_pth)
            os.unlink(pyd_pth)

    if sys.executable != py_executable:
        # FIXME: could I just hard link?
        executable = sys.executable
        shutil.copyfile(executable, py_executable)
        make_exe(py_executable)
        if is_win or is_cygwin:
            pythonw = os.path.join(os.path.dirname(sys.executable), "pythonw.exe")
            if os.path.exists(pythonw):
                logger.info("Also created pythonw.exe")
                shutil.copyfile(pythonw, os.path.join(os.path.dirname(py_executable), "pythonw.exe"))
            python_d = os.path.join(os.path.dirname(sys.executable), "python_d.exe")
            python_d_dest = os.path.join(os.path.dirname(py_executable), "python_d.exe")
            if os.path.exists(python_d):
                logger.info("Also created python_d.exe")
                shutil.copyfile(python_d, python_d_dest)
            elif os.path.exists(python_d_dest):
                logger.info("Removed python_d.exe as it is no longer at the source")
                os.unlink(python_d_dest)

            # we need to copy the DLL to enforce that windows will load the correct one.
            # may not exist if we are cygwin.
            if is_pypy:
                py_executable_dlls = [("libpypy-c.dll", "libpypy_d-c.dll")]
            else:
                py_executable_dlls = [
                    ("python%s.dll" % (sys.version_info[0]), "python%s_d.dll" % (sys.version_info[0])),
                    (
                        "python{}{}.dll".format(sys.version_info[0], sys.version_info[1]),
                        "python{}{}_d.dll".format(sys.version_info[0], sys.version_info[1]),
                    ),
                ]

            for py_executable_dll, py_executable_dll_d in py_executable_dlls:
                pythondll = os.path.join(os.path.dirname(sys.executable), py_executable_dll)
                pythondll_d = os.path.join(os.path.dirname(sys.executable), py_executable_dll_d)
                pythondll_d_dest = os.path.join(os.path.dirname(py_executable), py_executable_dll_d)
                if os.path.exists(pythondll):
                    logger.info("Also created %s" % py_executable_dll)
                    shutil.copyfile(pythondll, os.path.join(os.path.dirname(py_executable), py_executable_dll))
                if os.path.exists(pythondll_d):
                    logger.info("Also created %s" % py_executable_dll_d)
                    shutil.copyfile(pythondll_d, pythondll_d_dest)
                elif os.path.exists(pythondll_d_dest):
                    logger.info("Removed %s as the source does not exist" % pythondll_d_dest)
                    os.unlink(pythondll_d_dest)
        if is_pypy:
            # make a symlink python --> pypy-c
            python_executable = os.path.join(os.path.dirname(py_executable), "python")
            if sys.platform in ("win32", "cygwin"):
                python_executable += ".exe"
            logger.info("Also created executable %s" % python_executable)
            copyfile(py_executable, python_executable, symlink)

            if is_win:
                for name in ["libexpat.dll", "libeay32.dll", "ssleay32.dll", "sqlite3.dll", "tcl85.dll", "tk85.dll"]:
                    src = join(prefix, name)
                    if os.path.exists(src):
                        copyfile(src, join(bin_dir, name), symlink)

                for d in sys.path:
                    if d.endswith("lib_pypy"):
                        break
                else:
                    logger.fatal("Could not find lib_pypy in sys.path")
                    raise SystemExit(3)
                logger.info("Copying lib_pypy")
                copyfile(d, os.path.join(home_dir, "lib_pypy"), symlink)

    if os.path.splitext(os.path.basename(py_executable))[0] != expected_exe:
        secondary_exe = os.path.join(os.path.dirname(py_executable), expected_exe)
        py_executable_ext = os.path.splitext(py_executable)[1]
        if py_executable_ext.lower() == ".exe":
            # python2.4 gives an extension of '.4' :P
            secondary_exe += py_executable_ext
        if os.path.exists(secondary_exe):
            logger.warn(
                "Not overwriting existing {} script {} (you must use {})".format(
                    expected_exe, secondary_exe, py_executable
                )
            )
        else:
            logger.notify("Also creating executable in %s" % secondary_exe)
            shutil.copyfile(sys.executable, secondary_exe)
            make_exe(secondary_exe)

    if ".framework" in prefix:
        if "Python.framework" in prefix:
            logger.debug("MacOSX Python framework detected")
            # Make sure we use the embedded interpreter inside
            # the framework, even if sys.executable points to
            # the stub executable in ${sys.prefix}/bin
            # See http://groups.google.com/group/python-virtualenv/
            #                              browse_thread/thread/17cab2f85da75951
            original_python = os.path.join(prefix, "Resources/Python.app/Contents/MacOS/Python")
        if "EPD" in prefix:
            logger.debug("EPD framework detected")
            original_python = os.path.join(prefix, "bin/python")
        shutil.copy(original_python, py_executable)

        # Copy the framework's dylib into the virtual
        # environment
        virtual_lib = os.path.join(home_dir, ".Python")

        if os.path.exists(virtual_lib):
            os.unlink(virtual_lib)
        copyfile(os.path.join(prefix, "Python"), virtual_lib, symlink)

        # And then change the install_name of the copied python executable
        try:
            mach_o_change(py_executable, os.path.join(prefix, "Python"), "@executable_path/../.Python")
        except Exception:
            e = sys.exc_info()[1]
            logger.warn("Could not call mach_o_change: %s. " "Trying to call install_name_tool instead." % e)
            try:
                call_subprocess(
                    [
                        "install_name_tool",
                        "-change",
                        os.path.join(prefix, "Python"),
                        "@executable_path/../.Python",
                        py_executable,
                    ]
                )
            except Exception:
                logger.fatal("Could not call install_name_tool -- you must " "have Apple's development tools installed")
                raise

    if not is_win:
        # Ensure that 'python', 'pythonX' and 'pythonX.Y' all exist
        py_exe_version_major = "python%s" % sys.version_info[0]
        py_exe_version_major_minor = "python{}.{}".format(sys.version_info[0], sys.version_info[1])
        py_exe_no_version = "python"
        required_symlinks = [py_exe_no_version, py_exe_version_major, py_exe_version_major_minor]

        py_executable_base = os.path.basename(py_executable)

        if py_executable_base in required_symlinks:
            # Don't try to symlink to yourself.
            required_symlinks.remove(py_executable_base)

        for pth in required_symlinks:
            full_pth = join(bin_dir, pth)
            if os.path.exists(full_pth):
                os.unlink(full_pth)
            if symlink:
                os.symlink(py_executable_base, full_pth)
            else:
                copyfile(py_executable, full_pth, symlink)

    cmd = [
        py_executable,
        "-c",
        "import sys;out=sys.stdout;" 'getattr(out, "buffer", out).write(sys.prefix.encode("utf-8"))',
    ]
    logger.info('Testing executable with %s %s "%s"' % tuple(cmd))
    try:
        proc = subprocess.Popen(cmd, stdout=subprocess.PIPE)
        proc_stdout, proc_stderr = proc.communicate()
    except OSError:
        e = sys.exc_info()[1]
        if e.errno == errno.EACCES:
            logger.fatal("ERROR: The executable {} could not be run: {}".format(py_executable, e))
            sys.exit(100)
        else:
            raise e

    proc_stdout = proc_stdout.strip().decode("utf-8")
    proc_stdout = os.path.normcase(os.path.abspath(proc_stdout))
    norm_home_dir = os.path.normcase(os.path.abspath(home_dir))
    if hasattr(norm_home_dir, "decode"):
        norm_home_dir = norm_home_dir.decode(sys.getfilesystemencoding())
    if proc_stdout != norm_home_dir:
        logger.fatal("ERROR: The executable %s is not functioning" % py_executable)
        logger.fatal("ERROR: It thinks sys.prefix is {!r} (should be {!r})".format(proc_stdout, norm_home_dir))
        logger.fatal("ERROR: virtualenv is not compatible with this system or executable")
        if is_win:
            logger.fatal(
                "Note: some Windows users have reported this error when they "
                'installed Python for "Only this user" or have multiple '
                "versions of Python installed. Copying the appropriate "
                "PythonXX.dll to the virtualenv Scripts/ directory may fix "
                "this problem."
            )
        sys.exit(100)
    else:
        logger.info("Got sys.prefix result: %r" % proc_stdout)

    pydistutils = os.path.expanduser("~/.pydistutils.cfg")
    if os.path.exists(pydistutils):
        logger.notify("Please make sure you remove any previous custom paths from " "your %s file." % pydistutils)
    # FIXME: really this should be calculated earlier

    fix_local_scheme(home_dir, symlink)

    if site_packages:
        if os.path.exists(site_packages_filename):
            logger.info("Deleting %s" % site_packages_filename)
            os.unlink(site_packages_filename)

    return py_executable


def install_activate(home_dir, bin_dir, prompt=None):
    if is_win or is_jython and os._name == "nt":
        files = {"activate.bat": ACTIVATE_BAT, "deactivate.bat": DEACTIVATE_BAT, "activate.ps1": ACTIVATE_PS}

        # MSYS needs paths of the form /c/path/to/file
        drive, tail = os.path.splitdrive(home_dir.replace(os.sep, "/"))
        home_dir_msys = (drive and "/%s%s" or "%s%s") % (drive[:1], tail)

        # Run-time conditional enables (basic) Cygwin compatibility
        home_dir_sh = """$(if [ "$OSTYPE" "==" "cygwin" ]; then cygpath -u '{}'; else echo '{}'; fi;)""".format(
            home_dir, home_dir_msys
        )
        files["activate"] = ACTIVATE_SH.replace("__VIRTUAL_ENV__", home_dir_sh)

    else:
        files = {"activate": ACTIVATE_SH}

        # suppling activate.fish in addition to, not instead of, the
        # bash script support.
        files["activate.fish"] = ACTIVATE_FISH

        # same for csh/tcsh support...
        files["activate.csh"] = ACTIVATE_CSH

        # same for powershell
        files["activate.ps1"] = ACTIVATE_PS

    files["activate_this.py"] = ACTIVATE_THIS

    install_files(home_dir, bin_dir, prompt, files)


def install_files(home_dir, bin_dir, prompt, files):
    if hasattr(home_dir, "decode"):
        home_dir = home_dir.decode(sys.getfilesystemencoding())
    vname = os.path.basename(home_dir)
    for name, content in files.items():
        content = content.replace("__VIRTUAL_PROMPT__", prompt or "")
        content = content.replace("__VIRTUAL_WINPROMPT__", prompt or "(%s)" % vname)
        content = content.replace("__VIRTUAL_ENV__", home_dir)
        content = content.replace("__VIRTUAL_NAME__", vname)
        content = content.replace("__BIN_NAME__", os.path.basename(bin_dir))
        content = content.replace("__PATH_SEP__", os.pathsep)
        writefile(os.path.join(bin_dir, name), content)


def install_python_config(home_dir, bin_dir, prompt=None):
    if sys.platform == "win32" or is_jython and os._name == "nt":
        files = {}
    else:
        files = {"python-config": PYTHON_CONFIG}
    install_files(home_dir, bin_dir, prompt, files)
    for name, _ in files.items():
        make_exe(os.path.join(bin_dir, name))


def install_distutils(home_dir):
    distutils_path = change_prefix(distutils.__path__[0], home_dir)
    mkdir(distutils_path)
    # FIXME: maybe this prefix setting should only be put in place if
    # there's a local distutils.cfg with a prefix setting?
    home_dir = os.path.abspath(home_dir)
    # FIXME: this is breaking things, removing for now:
    # distutils_cfg = DISTUTILS_CFG + "\n[install]\nprefix=%s\n" % home_dir
    writefile(os.path.join(distutils_path, "__init__.py"), DISTUTILS_INIT)
    writefile(os.path.join(distutils_path, "distutils.cfg"), DISTUTILS_CFG, overwrite=False)


def fix_local_scheme(home_dir, symlink=True):
    """
    Platforms that use the "posix_local" install scheme (like Ubuntu with
    Python 2.7) need to be given an additional "local" location, sigh.
    """
    try:
        import sysconfig
    except ImportError:
        pass
    else:
        if sysconfig._get_default_scheme() == "posix_local":
            local_path = os.path.join(home_dir, "local")
            if not os.path.exists(local_path):
                os.mkdir(local_path)
                for subdir_name in os.listdir(home_dir):
                    if subdir_name == "local":
                        continue
                    copyfile(
                        os.path.abspath(os.path.join(home_dir, subdir_name)),
                        os.path.join(local_path, subdir_name),
                        symlink,
                    )


def fix_lib64(lib_dir, symlink=True):
    """
    Some platforms (particularly Gentoo on x64) put things in lib64/pythonX.Y
    instead of lib/pythonX.Y.  If this is such a platform we'll just create a
    symlink so lib64 points to lib
    """
    # PyPy's library path scheme is not affected by this.
    # Return early or we will die on the following assert.
    if is_pypy:
        logger.debug("PyPy detected, skipping lib64 symlinking")
        return
    # Check we have a lib64 library path
    if not [p for p in distutils.sysconfig.get_config_vars().values() if isinstance(p, basestring) and "lib64" in p]:
        return

    logger.debug("This system uses lib64; symlinking lib64 to lib")

    assert os.path.basename(lib_dir) == "python%s" % sys.version[:3], "Unexpected python lib dir: %r" % lib_dir
    lib_parent = os.path.dirname(lib_dir)
    top_level = os.path.dirname(lib_parent)
    lib_dir = os.path.join(top_level, "lib")
    lib64_link = os.path.join(top_level, "lib64")
    assert os.path.basename(lib_parent) == "lib", "Unexpected parent dir: %r" % lib_parent
    if os.path.lexists(lib64_link):
        return
    if symlink:
        os.symlink(lib_dir, lib64_link)
    else:
        copyfile(lib_dir, lib64_link)


def resolve_interpreter(exe):
    """
    If the executable given isn't an absolute path, search $PATH for the interpreter
    """
    # If the "executable" is a version number, get the installed executable for
    # that version
    orig_exe = exe
    python_versions = get_installed_pythons()
    if exe in python_versions:
        exe = python_versions[exe]

    if os.path.abspath(exe) != exe:
        exe = distutils.spawn.find_executable(exe) or exe
    if not os.path.exists(exe):
        logger.fatal("The path {} (from --python={}) does not exist".format(exe, orig_exe))
        raise SystemExit(3)
    if not is_executable(exe):
        logger.fatal("The path {} (from --python={}) is not an executable file".format(exe, orig_exe))
        raise SystemExit(3)
    return exe


def is_executable(exe):
    """Checks a file is executable"""
    return os.path.isfile(exe) and os.access(exe, os.X_OK)


# Relocating the environment:
def make_environment_relocatable(home_dir):
    """
    Makes the already-existing environment use relative paths, and takes out
    the #!-based environment selection in scripts.
    """
    home_dir, lib_dir, inc_dir, bin_dir = path_locations(home_dir)
    activate_this = os.path.join(bin_dir, "activate_this.py")
    if not os.path.exists(activate_this):
        logger.fatal(
            "The environment doesn't have a file %s -- please re-run virtualenv "
            "on this environment to update it" % activate_this
        )
    fixup_scripts(home_dir, bin_dir)
    fixup_pth_and_egg_link(home_dir)
    # FIXME: need to fix up distutils.cfg


OK_ABS_SCRIPTS = [
    "python",
    "python%s" % sys.version[:3],
    "activate",
    "activate.bat",
    "activate_this.py",
    "activate.fish",
    "activate.csh",
]


def fixup_scripts(home_dir, bin_dir):
    if is_win:
        new_shebang_args = ("%s /c" % os.path.normcase(os.environ.get("COMSPEC", "cmd.exe")), "", ".exe")
    else:
        new_shebang_args = ("/usr/bin/env", sys.version[:3], "")

    # This is what we expect at the top of scripts:
    shebang = "#!%s" % os.path.normcase(os.path.join(os.path.abspath(bin_dir), "python%s" % new_shebang_args[2]))
    # This is what we'll put:
    new_shebang = "#!%s python%s%s" % new_shebang_args

    for filename in os.listdir(bin_dir):
        filename = os.path.join(bin_dir, filename)
        if not os.path.isfile(filename):
            # ignore subdirs, e.g. .svn ones.
            continue
        lines = None
        with open(filename, "rb") as f:
            try:
                lines = f.read().decode("utf-8").splitlines()
            except UnicodeDecodeError:
                # This is probably a binary program instead
                # of a script, so just ignore it.
                continue
        if not lines:
            logger.warn("Script %s is an empty file" % filename)
            continue

        old_shebang = lines[0].strip()
        old_shebang = old_shebang[0:2] + os.path.normcase(old_shebang[2:])

        if not old_shebang.startswith(shebang):
            if os.path.basename(filename) in OK_ABS_SCRIPTS:
                logger.debug("Cannot make script %s relative" % filename)
            elif lines[0].strip() == new_shebang:
                logger.info("Script %s has already been made relative" % filename)
            else:
                logger.warn(
                    "Script %s cannot be made relative (it's not a normal script that starts with %s)"
                    % (filename, shebang)
                )
            continue
        logger.notify("Making script %s relative" % filename)
        script = relative_script([new_shebang] + lines[1:])
        with open(filename, "wb") as f:
            f.write("\n".join(script).encode("utf-8"))


def relative_script(lines):
    "Return a script that'll work in a relocatable environment."
    activate = (
        "import os; "
        "activate_this=os.path.join(os.path.dirname(os.path.realpath(__file__)), 'activate_this.py'); "
        "exec(compile(open(activate_this).read(), activate_this, 'exec'), dict(__file__=activate_this)); "
        "del os, activate_this"
    )
    # Find the last future statement in the script. If we insert the activation
    # line before a future statement, Python will raise a SyntaxError.
    activate_at = None
    for idx, line in reversed(list(enumerate(lines))):
        if line.split()[:3] == ["from", "__future__", "import"]:
            activate_at = idx + 1
            break
    if activate_at is None:
        # Activate after the shebang.
        activate_at = 1
    return lines[:activate_at] + ["", activate, ""] + lines[activate_at:]


def fixup_pth_and_egg_link(home_dir, sys_path=None):
    """Makes .pth and .egg-link files use relative paths"""
    home_dir = os.path.normcase(os.path.abspath(home_dir))
    if sys_path is None:
        sys_path = sys.path
    for path in sys_path:
        if not path:
            path = "."
        if not os.path.isdir(path):
            continue
        path = os.path.normcase(os.path.abspath(path))
        if not path.startswith(home_dir):
            logger.debug("Skipping system (non-environment) directory %s" % path)
            continue
        for filename in os.listdir(path):
            filename = os.path.join(path, filename)
            if filename.endswith(".pth"):
                if not os.access(filename, os.W_OK):
                    logger.warn("Cannot write .pth file %s, skipping" % filename)
                else:
                    fixup_pth_file(filename)
            if filename.endswith(".egg-link"):
                if not os.access(filename, os.W_OK):
                    logger.warn("Cannot write .egg-link file %s, skipping" % filename)
                else:
                    fixup_egg_link(filename)


def fixup_pth_file(filename):
    lines = []
    prev_lines = []
    with open(filename) as f:
        prev_lines = f.readlines()
    for line in prev_lines:
        line = line.strip()
        if not line or line.startswith("#") or line.startswith("import ") or os.path.abspath(line) != line:
            lines.append(line)
        else:
            new_value = make_relative_path(filename, line)
            if line != new_value:
                logger.debug("Rewriting path {} as {} (in {})".format(line, new_value, filename))
            lines.append(new_value)
    if lines == prev_lines:
        logger.info("No changes to .pth file %s" % filename)
        return
    logger.notify("Making paths in .pth file %s relative" % filename)
    with open(filename, "w") as f:
        f.write("\n".join(lines) + "\n")


def fixup_egg_link(filename):
    with open(filename) as f:
        link = f.readline().strip()
    if os.path.abspath(link) != link:
        logger.debug("Link in %s already relative" % filename)
        return
    new_link = make_relative_path(filename, link)
    logger.notify("Rewriting link {} in {} as {}".format(link, filename, new_link))
    with open(filename, "w") as f:
        f.write(new_link)


def make_relative_path(source, dest, dest_is_directory=True):
    """
    Make a filename relative, where the filename is dest, and it is
    being referred to from the filename source.

        >>> make_relative_path('/usr/share/something/a-file.pth',
        ...                    '/usr/share/another-place/src/Directory')
        '../another-place/src/Directory'
        >>> make_relative_path('/usr/share/something/a-file.pth',
        ...                    '/home/user/src/Directory')
        '../../../home/user/src/Directory'
        >>> make_relative_path('/usr/share/a-file.pth', '/usr/share/')
        './'
    """
    source = os.path.dirname(source)
    if not dest_is_directory:
        dest_filename = os.path.basename(dest)
        dest = os.path.dirname(dest)
    dest = os.path.normpath(os.path.abspath(dest))
    source = os.path.normpath(os.path.abspath(source))
    dest_parts = dest.strip(os.path.sep).split(os.path.sep)
    source_parts = source.strip(os.path.sep).split(os.path.sep)
    while dest_parts and source_parts and dest_parts[0] == source_parts[0]:
        dest_parts.pop(0)
        source_parts.pop(0)
    full_parts = [".."] * len(source_parts) + dest_parts
    if not dest_is_directory:
        full_parts.append(dest_filename)
    if not full_parts:
        # Special case for the current directory (otherwise it'd be '')
        return "./"
    return os.path.sep.join(full_parts)


# Bootstrap script creation:
def create_bootstrap_script(extra_text, python_version=""):
    """
    Creates a bootstrap script, which is like this script but with
    extend_parser, adjust_options, and after_install hooks.

    This returns a string that (written to disk of course) can be used
    as a bootstrap script with your own customizations.  The script
    will be the standard virtualenv.py script, with your extra text
    added (your extra text should be Python code).

    If you include these functions, they will be called:

    ``extend_parser(optparse_parser)``:
        You can add or remove options from the parser here.

    ``adjust_options(options, args)``:
        You can change options here, or change the args (if you accept
        different kinds of arguments, be sure you modify ``args`` so it is
        only ``[DEST_DIR]``).

    ``after_install(options, home_dir)``:

        After everything is installed, this function is called.  This
        is probably the function you are most likely to use.  An
        example would be::

            def after_install(options, home_dir):
                subprocess.call([join(home_dir, 'bin', 'easy_install'),
                                 'MyPackage'])
                subprocess.call([join(home_dir, 'bin', 'my-package-script'),
                                 'setup', home_dir])

        This example immediately installs a package, and runs a setup
        script from that package.

    If you provide something like ``python_version='2.5'`` then the
    script will start with ``#!/usr/bin/env python2.5`` instead of
    ``#!/usr/bin/env python``.  You can use this when the script must
    be run with a particular Python version.
    """
    filename = __file__
    if filename.endswith(".pyc"):
        filename = filename[:-1]
    with codecs.open(filename, "r", encoding="utf-8") as f:
        content = f.read()
    py_exe = "python%s" % python_version
    content = ("#!/usr/bin/env %s\n" % py_exe) + "# WARNING: This file is generated\n" + content
    return content.replace("##EXT" "END##", extra_text)


# EXTEND
def convert(s):
    b = base64.b64decode(s.encode("ascii"))
    return zlib.decompress(b).decode("utf-8")


# file site.py
SITE_PY = convert(
    """

AfPVUFM=
"""
)

# file activate.sh
ACTIVATE_SH = convert(
    """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"""
)

# file activate.fish
ACTIVATE_FISH = convert(
    """
eJyFVlFv2zYQftevuMoOnBS1g70WGIZ08RADSRw4boBhGGhGOsUcKFIjKbUu9uN7lCyJsrVWDxZE
fnf38e6+oyew3QsLmZAIeWkdvCKUFlP6EeoNdlaXJkF4FeqaJ05U3OEiE3a/g/dfhNsLBRxMqZQH
+3W4hL1zxcfra/9l9yjlItE5XIFFa4VW7xfRBG41KO28IQgHqTCYOHlYRFFWKoqiFaTYhoN5CrPl
V8JVwriSS1QV5DpF4CoFg640CpwGt0dyanIugRDCaJWjcotZBPRMCGjRgZZpuAsVN4K/SrQ1SmTg
kHIwVxBP2fr+lr2sNtvPN/fs6WZ7F9cY/3hP87ev4FfhHDjEIYwDUKXRz6L+ub1bP96tH5Yjsbu9
Uwbdxo95DGE/YPPH6vmOPW3WD09btn5Zbjar24DPBJ7JO1eAeeEOIHVCBdhNffVZW01WcEcdQ0Xi
UuovdakM5roiqM5gV4MLo8nDrm281tYS891ieBQJ5+6jgNHScItBu8zsSYymc6zTBmsy2og3objs
44ThIbAdAyTAqK9YgPqZBZ5ZjNZqLPPDah3RbVGXjy/DKsZTbt6qv375O4Z3v8JMaZXSsim9tnA2
KKLM5u3eu3HOxSHVyfhWL9eOX81xAp+V5yiMQYkVDyW3iAKRD5lFUdvmwckgZiz4ZCzuYWcSg2kt
tIFS42lgfs3Yp9Uje7x5WJKnI7zju5v2+tj5bNLiImreMP8XTtQzTiNQ6BgeQy91trrp12e6OLg9
LczzZg3qejboTqnfhidjt6vnm0/3y2PnxMcB+LsuDnWzJyUVgwoxlEQXm5NYTrvzKMBBz4ftftbN
A/ioGqjleIUDQlPruCvtB8i0CW0sobi/Jmwh+YFujLNx4MM3xq2TcBw8NSR1hcYIujfIa0Xv9LcA
s8r8jfQB/vF3YGGwoBTX5MLbQvEc+9jhpOw78yhX1k/IuoxGKJfB7MJe2NkoHC7pLCzRks7eXGNX
nQeUFv/H3eWFvYLZiDFcvtIQ9IyH3REHbtsp0qRgMzIQu3R2NsleQ4z+Op72WY/hP2j+KXTA0QE3
nFutYMbG3AnpuuO/AygvqEs=
"""
)

# file activate.csh
ACTIVATE_CSH = convert(
    """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"""
)

# file activate.bat
ACTIVATE_BAT = convert(
    """
eJx9Ul9LhEAQfxf8DoOclI/dYyFkaCmcq4gZQTBUrincuZFbff12T133TM+nnd35/Zvxlr7XDFhV
mUZHOVhFlOWP3g4DUriIWoVomYZpNBWUtGpaWgImO191pFkSpzlcmgaI70jVX7n2Qp8tuByg+46O
CMHbMq64T+nmlJt082D1T44muCDk2prgEHF4mdI9RaS/QwSt3zSyIAaftRccvqVTBziD1x/WlPD5
xd729NDBb8Nr4DU9QNMKsJeH9pkhPedhQsIkDuCDCa6A+NF9IevVFAohkqizdHetg/tkWvPoftWJ
MCqnOxv7/x7Np6yv9P2Ker5dmX8yNyCkkWnbZy3N5LarczlqL8htx2EM9rQ/2H5BvIsIEi8OEG8U
+g8CsNTr
"""
)

# file deactivate.bat
DEACTIVATE_BAT = convert(
    """
eJyFkN0KgkAUhO8X9h0GQapXCIQEDQX/EBO6kso1F9KN3Or1201Si6JzN+fMGT5mxQ61gKgqSijp
mETup9nGDgo3yi29S90QjmhnEteOYb6AFNjdBC9xvoj9iTUd7lzWkDVrwFuYiZ15JiW8QiskSlbx
lpUo4sApXtlJGodJhqNQWW7k+Ou831ACNZrC6BeW+eXPNEbfl7OiXr6H/oHZZl4ceXHoToG0nuIM
pk+k4fAba/wd0Pr4P2CqyLeOlJ4iKfkJo6v/iaH9YzfPMEoeMG2RUA==
"""
)

# file activate.ps1
ACTIVATE_PS = convert(
    """

CxQqtDi7qZkJ2W6TFaeFtKPYvdF9+fL6LyUq877/h9L/AoalQfY=
"""
)

# file distutils-init.py
DISTUTILS_INIT = convert(
    """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"""
)

# file distutils.cfg
DISTUTILS_CFG = convert(
    """
eJxNj00KwkAMhfc9xYNuxe4Ft57AjYiUtDO1wXSmNJnK3N5pdSEEAu8nH6lxHVlRhtDHMPATA4uH
xJ4EFmGbvfJiicSHFRzUSISMY6hq3GLCRLnIvSTnEefN0FIjw5tF0Hkk9Q5dRunBsVoyFi24aaLg
9FDOlL0FPGluf4QjcInLlxd6f6rqkgPu/5nHLg0cXCscXoozRrP51DRT3j9QNl99AP53T2Q=
"""
)

# file activate_this.py
ACTIVATE_THIS = convert(
    """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"""
)

# file python-config
PYTHON_CONFIG = convert(
    """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"""
)

MH_MAGIC = 0xFEEDFACE
MH_CIGAM = 0xCEFAEDFE
MH_MAGIC_64 = 0xFEEDFACF
MH_CIGAM_64 = 0xCFFAEDFE
FAT_MAGIC = 0xCAFEBABE
BIG_ENDIAN = ">"
LITTLE_ENDIAN = "<"
LC_LOAD_DYLIB = 0xC
maxint = majver == 3 and getattr(sys, "maxsize") or getattr(sys, "maxint")


class fileview(object):
    """
    A proxy for file-like objects that exposes a given view of a file.
    Modified from macholib.
    """

    def __init__(self, fileobj, start=0, size=maxint):
        if isinstance(fileobj, fileview):
            self._fileobj = fileobj._fileobj
        else:
            self._fileobj = fileobj
        self._start = start
        self._end = start + size
        self._pos = 0

    def __repr__(self):
        return "<fileview [%d, %d] %r>" % (self._start, self._end, self._fileobj)

    def tell(self):
        return self._pos

    def _checkwindow(self, seekto, op):
        if not (self._start <= seekto <= self._end):
            raise IOError("%s to offset %d is outside window [%d, %d]" % (op, seekto, self._start, self._end))

    def seek(self, offset, whence=0):
        seekto = offset
        if whence == os.SEEK_SET:
            seekto += self._start
        elif whence == os.SEEK_CUR:
            seekto += self._start + self._pos
        elif whence == os.SEEK_END:
            seekto += self._end
        else:
            raise IOError("Invalid whence argument to seek: {!r}".format(whence))
        self._checkwindow(seekto, "seek")
        self._fileobj.seek(seekto)
        self._pos = seekto - self._start

    def write(self, bytes):
        here = self._start + self._pos
        self._checkwindow(here, "write")
        self._checkwindow(here + len(bytes), "write")
        self._fileobj.seek(here, os.SEEK_SET)
        self._fileobj.write(bytes)
        self._pos += len(bytes)

    def read(self, size=maxint):
        assert size >= 0
        here = self._start + self._pos
        self._checkwindow(here, "read")
        size = min(size, self._end - here)
        self._fileobj.seek(here, os.SEEK_SET)
        bytes = self._fileobj.read(size)
        self._pos += len(bytes)
        return bytes


def read_data(file, endian, num=1):
    """
    Read a given number of 32-bits unsigned integers from the given file
    with the given endianness.
    """
    res = struct.unpack(endian + "L" * num, file.read(num * 4))
    if len(res) == 1:
        return res[0]
    return res


def mach_o_change(path, what, value):
    """
    Replace a given name (what) in any LC_LOAD_DYLIB command found in
    the given binary with a new name (value), provided it's shorter.
    """

    def do_macho(file, bits, endian):
        # Read Mach-O header (the magic number is assumed read by the caller)
        cputype, cpusubtype, filetype, ncmds, sizeofcmds, flags = read_data(file, endian, 6)
        # 64-bits header has one more field.
        if bits == 64:
            read_data(file, endian)
        # The header is followed by ncmds commands
        for _ in range(ncmds):
            where = file.tell()
            # Read command header
            cmd, cmdsize = read_data(file, endian, 2)
            if cmd == LC_LOAD_DYLIB:
                # The first data field in LC_LOAD_DYLIB commands is the
                # offset of the name, starting from the beginning of the
                # command.
                name_offset = read_data(file, endian)
                file.seek(where + name_offset, os.SEEK_SET)
                # Read the NUL terminated string
                load = file.read(cmdsize - name_offset).decode()
                load = load[: load.index("\0")]
                # If the string is what is being replaced, overwrite it.
                if load == what:
                    file.seek(where + name_offset, os.SEEK_SET)
                    file.write(value.encode() + "\0".encode())
            # Seek to the next command
            file.seek(where + cmdsize, os.SEEK_SET)

    def do_file(file, offset=0, size=maxint):
        file = fileview(file, offset, size)
        # Read magic number
        magic = read_data(file, BIG_ENDIAN)
        if magic == FAT_MAGIC:
            # Fat binaries contain nfat_arch Mach-O binaries
            nfat_arch = read_data(file, BIG_ENDIAN)
            for _ in range(nfat_arch):
                # Read arch header
                cputype, cpusubtype, offset, size, align = read_data(file, BIG_ENDIAN, 5)
                do_file(file, offset, size)
        elif magic == MH_MAGIC:
            do_macho(file, 32, BIG_ENDIAN)
        elif magic == MH_CIGAM:
            do_macho(file, 32, LITTLE_ENDIAN)
        elif magic == MH_MAGIC_64:
            do_macho(file, 64, BIG_ENDIAN)
        elif magic == MH_CIGAM_64:
            do_macho(file, 64, LITTLE_ENDIAN)

    assert len(what) >= len(value)

    with open(path, "r+b") as f:
        do_file(f)


if __name__ == "__main__":
    main()

# TODO:
# Copy python.exe.manifest
# Monkeypatch distutils.sysconfig
