Issue #18571: Implementation of the PEP 446: file descriptors and file handles

are now created non-inheritable; add functions os.get/set_inheritable(),
os.get/set_handle_inheritable() and socket.socket.get/set_inheritable().

6 files changed, 15 insertions, 11 deletions

diff --git a/Lib/multiprocessing/connection.py b/Lib/multiprocessing/connection.py
index 443fa7e..9fbe46d 100644
--- a/Lib/multiprocessing/connection.py
+++ b/Lib/multiprocessing/connection.py
@@ -509,7 +509,7 @@ if sys.platform != 'win32':
             c1 = Connection(s1.detach())
             c2 = Connection(s2.detach())
         else:
-            fd1, fd2 = util.pipe()
+            fd1, fd2 = os.pipe()
             c1 = Connection(fd1, writable=False)
             c2 = Connection(fd2, readable=False)
 
@@ -536,7 +536,9 @@ else:
             _winapi.FILE_FLAG_FIRST_PIPE_INSTANCE,
             _winapi.PIPE_TYPE_MESSAGE | _winapi.PIPE_READMODE_MESSAGE |
             _winapi.PIPE_WAIT,
-            1, obsize, ibsize, _winapi.NMPWAIT_WAIT_FOREVER, _winapi.NULL
+            1, obsize, ibsize, _winapi.NMPWAIT_WAIT_FOREVER,
+            # default security descriptor: the handle cannot be inherited
+            _winapi.NULL
             )
         h2 = _winapi.CreateFile(
             address, access, 0, _winapi.NULL, _winapi.OPEN_EXISTING,
diff --git a/Lib/multiprocessing/forkserver.py b/Lib/multiprocessing/forkserver.py
index 208bd4e..11df382 100644
--- a/Lib/multiprocessing/forkserver.py
+++ b/Lib/multiprocessing/forkserver.py
@@ -60,8 +60,8 @@ def connect_to_new_process(fds):
         raise ValueError('too many fds')
     with socket.socket(socket.AF_UNIX) as client:
         client.connect(_forkserver_address)
-        parent_r, child_w = util.pipe()
-        child_r, parent_w = util.pipe()
+        parent_r, child_w = os.pipe()
+        child_r, parent_w = os.pipe()
         allfds = [child_r, child_w, _forkserver_alive_fd,
                   semaphore_tracker._semaphore_tracker_fd]
         allfds += fds
diff --git a/Lib/multiprocessing/popen_fork.py b/Lib/multiprocessing/popen_fork.py
index fd25ddc..c9f3aae 100644
--- a/Lib/multiprocessing/popen_fork.py
+++ b/Lib/multiprocessing/popen_fork.py
@@ -66,7 +66,7 @@ class Popen(object):
 
     def _launch(self, process_obj):
         code = 1
-        parent_r, child_w = util.pipe()
+        parent_r, child_w = os.pipe()
         self.pid = os.fork()
         if self.pid == 0:
             try:
diff --git a/Lib/multiprocessing/popen_spawn_posix.py b/Lib/multiprocessing/popen_spawn_posix.py
index e67915d..751bf22 100644
--- a/Lib/multiprocessing/popen_spawn_posix.py
+++ b/Lib/multiprocessing/popen_spawn_posix.py
@@ -54,8 +54,8 @@ class Popen(popen_fork.Popen):
 
         parent_r = child_w = child_r = parent_w = None
         try:
-            parent_r, child_w = util.pipe()
-            child_r, parent_w = util.pipe()
+            parent_r, child_w = os.pipe()
+            child_r, parent_w = os.pipe()
             cmd = spawn.get_command_line(tracker_fd=tracker_fd,
                                          pipe_handle=child_r)
             self._fds.extend([child_r, child_w])
diff --git a/Lib/multiprocessing/semaphore_tracker.py b/Lib/multiprocessing/semaphore_tracker.py
index 99a0dd4..6c9e4a5 100644
--- a/Lib/multiprocessing/semaphore_tracker.py
+++ b/Lib/multiprocessing/semaphore_tracker.py
@@ -45,7 +45,7 @@ def ensure_running():
         except Exception:
             pass
         cmd = 'from multiprocessing.semaphore_tracker import main; main(%d)'
-        r, w = util.pipe()
+        r, w = os.pipe()
         try:
             fds_to_pass.append(r)
             # process will out live us, so no need to wait on pid
diff --git a/Lib/multiprocessing/util.py b/Lib/multiprocessing/util.py
index d9e4799..ac8e913 100644
--- a/Lib/multiprocessing/util.py
+++ b/Lib/multiprocessing/util.py
@@ -365,7 +365,7 @@ def spawnv_passfds(path, args, passfds):
         if flag & fcntl.FD_CLOEXEC:
             fcntl.fcntl(fd, fcntl.F_SETFD, flag & ~fcntl.FD_CLOEXEC)
             tmp.append((fd, flag))
-    errpipe_read, errpipe_write = _posixsubprocess.cloexec_pipe()
+    errpipe_read, errpipe_write = os.pipe()
     try:
         return _posixsubprocess.fork_exec(
             args, [os.fsencode(path)], True, passfds, None, None,
@@ -381,7 +381,9 @@ def spawnv_passfds(path, args, passfds):
 #
 # Return pipe with CLOEXEC set on fds
 #
+# Deprecated: os.pipe() creates non-inheritable file descriptors
+# since Python 3.4
+#
 
 def pipe():
-    import _posixsubprocess
-    return _posixsubprocess.cloexec_pipe()
+    return os.pipe()