use new _winapi instead of removed _subprocess

`_subprocess` is removed in Python 3.3, and the relevant names
relocated to a new `_winapi` module.

ref: http://bugs.python.org/issue11750

closes  #2471

should be back ported to 0.13.1

IPython/zmq/entry_point.py

@@ -1,222 +1,226
 """ Defines helper functions for creating kernel entry points and process
 launchers.
 """
 
 # Standard library imports.
 import atexit
 import json
 import os
 import socket
 from subprocess import Popen, PIPE
 import sys
 import tempfile
 
 # System library imports
 
 # IPython imports
 from IPython.utils.localinterfaces import LOCALHOST
 from IPython.utils.py3compat import bytes_to_str
 
 # Local imports.
 from parentpoller import ParentPollerWindows
 
 def write_connection_file(fname=None, shell_port=0, iopub_port=0, stdin_port=0, hb_port=0,
                          ip=LOCALHOST, key=b'', transport='tcp'):
     """Generates a JSON config file, including the selection of random ports.
     
     Parameters
     ----------
 
     fname : unicode
         The path to the file to write
 
     shell_port : int, optional
         The port to use for ROUTER channel.
 
     iopub_port : int, optional
         The port to use for the SUB channel.
 
     stdin_port : int, optional
         The port to use for the REQ (raw input) channel.
 
     hb_port : int, optional
         The port to use for the hearbeat REP channel.
 
     ip  : str, optional
         The ip address the kernel will bind to.
 
     key : str, optional
         The Session key used for HMAC authentication.
 
     """
     # default to temporary connector file
     if not fname:
         fname = tempfile.mktemp('.json')
     
     # Find open ports as necessary.
     
     ports = []
     ports_needed = int(shell_port <= 0) + int(iopub_port <= 0) + \
                    int(stdin_port <= 0) + int(hb_port <= 0)
     if transport == 'tcp':
         for i in range(ports_needed):
             sock = socket.socket()
             sock.bind(('', 0))
             ports.append(sock)
         for i, sock in enumerate(ports):
             port = sock.getsockname()[1]
             sock.close()
             ports[i] = port
     else:
         N = 1
         for i in range(ports_needed):
             while os.path.exists("%s-%s" % (ip, str(N))):
                 N += 1
             ports.append(N)
             N += 1
     if shell_port <= 0:
         shell_port = ports.pop(0)
     if iopub_port <= 0:
         iopub_port = ports.pop(0)
     if stdin_port <= 0:
         stdin_port = ports.pop(0)
     if hb_port <= 0:
         hb_port = ports.pop(0)
     
     cfg = dict( shell_port=shell_port,
                 iopub_port=iopub_port,
                 stdin_port=stdin_port,
                 hb_port=hb_port,
               )
     cfg['ip'] = ip
     cfg['key'] = bytes_to_str(key)
     cfg['transport'] = transport
     
     with open(fname, 'w') as f:
         f.write(json.dumps(cfg, indent=2))
     
     return fname, cfg
     
 
 def base_launch_kernel(code, fname, stdin=None, stdout=None, stderr=None,
                         executable=None, independent=False, extra_arguments=[],
                         cwd=None):
     """ Launches a localhost kernel, binding to the specified ports.
 
     Parameters
     ----------
     code : str,
         A string of Python code that imports and executes a kernel entry point.
 
     stdin, stdout, stderr : optional (default None)
         Standards streams, as defined in subprocess.Popen.
 
     fname : unicode, optional
         The JSON connector file, containing ip/port/hmac key information.
 
     key : str, optional
         The Session key used for HMAC authentication.
 
     executable : str, optional (default sys.executable)
         The Python executable to use for the kernel process.
 
     independent : bool, optional (default False)
         If set, the kernel process is guaranteed to survive if this process
         dies. If not set, an effort is made to ensure that the kernel is killed
         when this process dies. Note that in this case it is still good practice
         to kill kernels manually before exiting.
 
     extra_arguments : list, optional
         A list of extra arguments to pass when executing the launch code.
     
     cwd : path, optional
         The working dir of the kernel process (default: cwd of this process).
 
     Returns
     -------
     A tuple of form:
         (kernel_process, shell_port, iopub_port, stdin_port, hb_port)
     where kernel_process is a Popen object and the ports are integers.
     """
     
     # Build the kernel launch command.
     if executable is None:
         executable = sys.executable
     arguments = [ executable, '-c', code, '-f', fname ]
     arguments.extend(extra_arguments)
 
     # Popen will fail (sometimes with a deadlock) if stdin, stdout, and stderr
     # are invalid. Unfortunately, there is in general no way to detect whether
     # they are valid.  The following two blocks redirect them to (temporary)
     # pipes in certain important cases.
 
     # If this process has been backgrounded, our stdin is invalid. Since there
     # is no compelling reason for the kernel to inherit our stdin anyway, we'll
     # place this one safe and always redirect.
     redirect_in = True
     _stdin = PIPE if stdin is None else stdin
 
     # If this process in running on pythonw, we know that stdin, stdout, and
     # stderr are all invalid.
     redirect_out = sys.executable.endswith('pythonw.exe')
     if redirect_out:
         _stdout = PIPE if stdout is None else stdout
         _stderr = PIPE if stderr is None else stderr
     else:
         _stdout, _stderr = stdout, stderr
 
     # Spawn a kernel.
     if sys.platform == 'win32':
         # Create a Win32 event for interrupting the kernel.
         interrupt_event = ParentPollerWindows.create_interrupt_event()
         arguments += [ '--interrupt=%i'%interrupt_event ]
 
         # If the kernel is running on pythonw and stdout/stderr are not been
         # re-directed, it will crash when more than 4KB of data is written to
         # stdout or stderr. This is a bug that has been with Python for a very
         # long time; see http://bugs.python.org/issue706263.
         # A cleaner solution to this problem would be to pass os.devnull to
         # Popen directly. Unfortunately, that does not work.
         if executable.endswith('pythonw.exe'):
             if stdout is None:
                 arguments.append('--no-stdout')
             if stderr is None:
                 arguments.append('--no-stderr')
 
         # Launch the kernel process.
         if independent:
             proc = Popen(arguments,
                          creationflags=512, # CREATE_NEW_PROCESS_GROUP
                          stdin=_stdin, stdout=_stdout, stderr=_stderr)
         else:
+            try:
+                from _winapi import DuplicateHandle, GetCurrentProcess, \
+                    DUPLICATE_SAME_ACCESS
+            except:
             from _subprocess import DuplicateHandle, GetCurrentProcess, \
                 DUPLICATE_SAME_ACCESS
             pid = GetCurrentProcess()
             handle = DuplicateHandle(pid, pid, pid, 0,
                                      True, # Inheritable by new processes.
                                      DUPLICATE_SAME_ACCESS)
             proc = Popen(arguments + ['--parent=%i'%int(handle)],
                          stdin=_stdin, stdout=_stdout, stderr=_stderr)
 
         # Attach the interrupt event to the Popen objet so it can be used later.
         proc.win32_interrupt_event = interrupt_event
 
     else:
         if independent:
             proc = Popen(arguments, preexec_fn=lambda: os.setsid(),
                          stdin=_stdin, stdout=_stdout, stderr=_stderr, cwd=cwd)
         else:
             proc = Popen(arguments + ['--parent=1'],
                          stdin=_stdin, stdout=_stdout, stderr=_stderr, cwd=cwd)
 
     # Clean up pipes created to work around Popen bug.
     if redirect_in:
         if stdin is None:
             proc.stdin.close()
     if redirect_out:
         if stdout is None:
             proc.stdout.close()
         if stderr is None:
             proc.stderr.close()
 
     return proc

IPython/zmq/parentpoller.py

@@ -1,136 +1,139
 # Standard library imports.
 try:
     import ctypes
 except:
     ctypes = None
 import os
 import platform
 import time
 from thread import interrupt_main
 from threading import Thread
 
 from IPython.utils.warn import warn
 
 
 class ParentPollerUnix(Thread):
     """ A Unix-specific daemon thread that terminates the program immediately
     when the parent process no longer exists.
     """
 
     def __init__(self):
         super(ParentPollerUnix, self).__init__()
         self.daemon = True
 
     def run(self):
         # We cannot use os.waitpid because it works only for child processes.
         from errno import EINTR
         while True:
             try:
                 if os.getppid() == 1:
                     os._exit(1)
                 time.sleep(1.0)
             except OSError as e:
                 if e.errno == EINTR:
                     continue
                 raise
 
 
 class ParentPollerWindows(Thread):
     """ A Windows-specific daemon thread that listens for a special event that
     signals an interrupt and, optionally, terminates the program immediately
     when the parent process no longer exists.
     """
 
     def __init__(self, interrupt_handle=None, parent_handle=None):
         """ Create the poller. At least one of the optional parameters must be
         provided.
 
         Parameters:
         -----------
         interrupt_handle : HANDLE (int), optional
             If provided, the program will generate a Ctrl+C event when this
             handle is signaled.
 
         parent_handle : HANDLE (int), optional
             If provided, the program will terminate immediately when this
             handle is signaled.
         """
         assert(interrupt_handle or parent_handle)
         super(ParentPollerWindows, self).__init__()
         if ctypes is None:
             raise ImportError("ParentPollerWindows requires ctypes")
         self.daemon = True
         self.interrupt_handle = interrupt_handle
         self.parent_handle = parent_handle
 
     @staticmethod
     def create_interrupt_event():
         """ Create an interrupt event handle.
 
         The parent process should use this static method for creating the
         interrupt event that is passed to the child process. It should store
         this handle and use it with ``send_interrupt`` to interrupt the child
         process.
         """
         # Create a security attributes struct that permits inheritance of the
         # handle by new processes.
         # FIXME: We can clean up this mess by requiring pywin32 for IPython.
         class SECURITY_ATTRIBUTES(ctypes.Structure):
             _fields_ = [ ("nLength", ctypes.c_int),
                          ("lpSecurityDescriptor", ctypes.c_void_p),
                          ("bInheritHandle", ctypes.c_int) ]
         sa = SECURITY_ATTRIBUTES()
         sa_p = ctypes.pointer(sa)
         sa.nLength = ctypes.sizeof(SECURITY_ATTRIBUTES)
         sa.lpSecurityDescriptor = 0
         sa.bInheritHandle = 1
 
         return ctypes.windll.kernel32.CreateEventA(
             sa_p,  # lpEventAttributes
             False, # bManualReset
             False, # bInitialState
             '')    # lpName
 
     @staticmethod
     def send_interrupt(interrupt_handle):
         """ Sends an interrupt event using the specified handle.
         """
         ctypes.windll.kernel32.SetEvent(interrupt_handle)
 
     def run(self):
         """ Run the poll loop. This method never returns.
         """
+        try:
+            from _winapi import WAIT_OBJECT_0, INFINITE
+        except ImportError:
         from _subprocess import WAIT_OBJECT_0, INFINITE
 
         # Build the list of handle to listen on.
         handles = []
         if self.interrupt_handle:
             handles.append(self.interrupt_handle)
         if self.parent_handle:
             handles.append(self.parent_handle)
         arch = platform.architecture()[0]
         c_int = ctypes.c_int64 if arch.startswith('64') else ctypes.c_int
 
         # Listen forever.
         while True:
             result = ctypes.windll.kernel32.WaitForMultipleObjects(
                 len(handles),                            # nCount
                 (c_int * len(handles))(*handles),        # lpHandles
                 False,                                   # bWaitAll
                 INFINITE)                                # dwMilliseconds
 
             if WAIT_OBJECT_0 <= result < len(handles):
                 handle = handles[result - WAIT_OBJECT_0]
 
                 if handle == self.interrupt_handle:
                     interrupt_main()
 
                 elif handle == self.parent_handle:
                     os._exit(1)
             elif result < 0:
                 # wait failed, just give up and stop polling.
                 warn("""Parent poll failed.  If the frontend dies,
                 the kernel may be left running.  Please let us know
                 about your system (bitness, Python, etc.) at
                 [e-mail]""")
                 return