1 files changed, 125 insertions, 0 deletions
diff --git a/third_party/python/setuptools/setuptools/_distutils/spawn.py b/third_party/python/setuptools/setuptools/_distutils/spawn.py
new file mode 100644
index 0000000000..fc592d4a91
--- /dev/null
+++ b/third_party/python/setuptools/setuptools/_distutils/spawn.py
@@ -0,0 +1,125 @@
+"""distutils.spawn
+
+Provides the 'spawn()' function, a front-end to various platform-
+specific functions for launching another program in a sub-process.
+Also provides the 'find_executable()' to search the path for a given
+executable name.
+"""
+
+import sys
+import os
+import subprocess
+
+from distutils.errors import DistutilsPlatformError, DistutilsExecError
+from distutils.debug import DEBUG
+from distutils import log
+
+
+if sys.platform == 'darwin':
+    _cfg_target = None
+    _cfg_target_split = None
+
+
+def spawn(cmd, search_path=1, verbose=0, dry_run=0, env=None):
+    """Run another program, specified as a command list 'cmd', in a new process.
+
+    'cmd' is just the argument list for the new process, ie.
+    cmd[0] is the program to run and cmd[1:] are the rest of its arguments.
+    There is no way to run a program with a name different from that of its
+    executable.
+
+    If 'search_path' is true (the default), the system's executable
+    search path will be used to find the program; otherwise, cmd[0]
+    must be the exact path to the executable.  If 'dry_run' is true,
+    the command will not actually be run.
+
+    Raise DistutilsExecError if running the program fails in any way; just
+    return on success.
+    """
+    # cmd is documented as a list, but just in case some code passes a tuple
+    # in, protect our %-formatting code against horrible death
+    cmd = list(cmd)
+
+    log.info(' '.join(cmd))
+    if dry_run:
+        return
+
+    if search_path:
+        executable = find_executable(cmd[0])
+        if executable is not None:
+            cmd[0] = executable
+
+    env = env if env is not None else dict(os.environ)
+
+    if sys.platform == 'darwin':
+        global _cfg_target, _cfg_target_split
+        if _cfg_target is None:
+            from distutils import sysconfig
+            _cfg_target = sysconfig.get_config_var(
+                                  'MACOSX_DEPLOYMENT_TARGET') or ''
+            if _cfg_target:
+                _cfg_target_split = [int(x) for x in _cfg_target.split('.')]
+        if _cfg_target:
+            # ensure that the deployment target of build process is not less
+            # than that used when the interpreter was built. This ensures
+            # extension modules are built with correct compatibility values
+            cur_target = os.environ.get('MACOSX_DEPLOYMENT_TARGET', _cfg_target)
+            if _cfg_target_split > [int(x) for x in cur_target.split('.')]:
+                my_msg = ('$MACOSX_DEPLOYMENT_TARGET mismatch: '
+                          'now "%s" but "%s" during configure'
+                                % (cur_target, _cfg_target))
+                raise DistutilsPlatformError(my_msg)
+            env.update(MACOSX_DEPLOYMENT_TARGET=cur_target)
+
+    try:
+        proc = subprocess.Popen(cmd, env=env)
+        proc.wait()
+        exitcode = proc.returncode
+    except OSError as exc:
+        if not DEBUG:
+            cmd = cmd[0]
+        raise DistutilsExecError(
+            "command %r failed: %s" % (cmd, exc.args[-1])) from exc
+
+    if exitcode:
+        if not DEBUG:
+            cmd = cmd[0]
+        raise DistutilsExecError(
+              "command %r failed with exit code %s" % (cmd, exitcode))
+
+
+def find_executable(executable, path=None):
+    """Tries to find 'executable' in the directories listed in 'path'.
+
+    A string listing directories separated by 'os.pathsep'; defaults to
+    os.environ['PATH'].  Returns the complete filename or None if not found.
+    """
+    _, ext = os.path.splitext(executable)
+    if (sys.platform == 'win32') and (ext != '.exe'):
+        executable = executable + '.exe'
+
+    if os.path.isfile(executable):
+        return executable
+
+    if path is None:
+        path = os.environ.get('PATH', None)
+        if path is None:
+            try:
+                path = os.confstr("CS_PATH")
+            except (AttributeError, ValueError):
+                # os.confstr() or CS_PATH is not available
+                path = os.defpath
+        # bpo-35755: Don't use os.defpath if the PATH environment variable is
+        # set to an empty string
+
+    # PATH='' doesn't match, whereas PATH=':' looks in the current directory
+    if not path:
+        return None
+
+    paths = path.split(os.pathsep)
+    for p in paths:
+        f = os.path.join(p, executable)
+        if os.path.isfile(f):
+            # the file exists, we have a shot at spawn working
+            return f
+    return None