Sync contrib/tools/python3 layout with upstream

* Move src/ subdir contents to the top of the layout
* Rename self-written lib -> lib2 to avoid CaseFolding warning from the VCS
* Regenerate contrib/libs/python proxy-headers accordingly
4ccc62ac1511abcf0fed14ccade38e984e088f1e

1 files changed, 83 insertions, 0 deletions

diff --git a/contrib/tools/python3/Lib/multiprocessing/popen_fork.py b/contrib/tools/python3/Lib/multiprocessing/popen_fork.py
new file mode 100644
index 00000000000..625981cf476
--- /dev/null
+++ b/contrib/tools/python3/Lib/multiprocessing/popen_fork.py
@@ -0,0 +1,83 @@
+import os
+import signal
+
+from . import util
+
+__all__ = ['Popen']
+
+#
+# Start child process using fork
+#
+
+class Popen(object):
+    method = 'fork'
+
+    def __init__(self, process_obj):
+        util._flush_std_streams()
+        self.returncode = None
+        self.finalizer = None
+        self._launch(process_obj)
+
+    def duplicate_for_child(self, fd):
+        return fd
+
+    def poll(self, flag=os.WNOHANG):
+        if self.returncode is None:
+            try:
+                pid, sts = os.waitpid(self.pid, flag)
+            except OSError:
+                # Child process not yet created. See #1731717
+                # e.errno == errno.ECHILD == 10
+                return None
+            if pid == self.pid:
+                self.returncode = os.waitstatus_to_exitcode(sts)
+        return self.returncode
+
+    def wait(self, timeout=None):
+        if self.returncode is None:
+            if timeout is not None:
+                from multiprocessing.connection import wait
+                if not wait([self.sentinel], timeout):
+                    return None
+            # This shouldn't block if wait() returned successfully.
+            return self.poll(os.WNOHANG if timeout == 0.0 else 0)
+        return self.returncode
+
+    def _send_signal(self, sig):
+        if self.returncode is None:
+            try:
+                os.kill(self.pid, sig)
+            except ProcessLookupError:
+                pass
+            except OSError:
+                if self.wait(timeout=0.1) is None:
+                    raise
+
+    def terminate(self):
+        self._send_signal(signal.SIGTERM)
+
+    def kill(self):
+        self._send_signal(signal.SIGKILL)
+
+    def _launch(self, process_obj):
+        code = 1
+        parent_r, child_w = os.pipe()
+        child_r, parent_w = os.pipe()
+        self.pid = os.fork()
+        if self.pid == 0:
+            try:
+                os.close(parent_r)
+                os.close(parent_w)
+                code = process_obj._bootstrap(parent_sentinel=child_r)
+            finally:
+                os._exit(code)
+        else:
+            os.close(child_w)
+            os.close(child_r)
+            self.finalizer = util.Finalize(self, util.close_fds,
+                                           (parent_r, parent_w,))
+            self.sentinel = parent_r
+
+    def close(self):
+        if self.finalizer is not None:
+            self.finalizer()