import os import msvcrt import signal import sys import _winapi from .context import reduction, get_spawning_popen, set_spawning_popen from . import spawn from . import util __all__ = ['Popen'] # # # # Exit code used by Popen.terminate() TERMINATE = 0x10000 WINEXE = (sys.platform == 'win32' and getattr(sys, 'frozen', False)) WINSERVICE = sys.executable.lower().endswith("pythonservice.exe") def _path_eq(p1, p2): return p1 == p2 or os.path.normcase(p1) == os.path.normcase(p2) WINENV = not _path_eq(sys.executable, sys._base_executable) def _close_handles(*handles): for handle in handles: _winapi.CloseHandle(handle) # # We define a Popen class similar to the one from subprocess, but # whose constructor takes a process object as its argument. # class Popen(object): ''' Start a subprocess to run the code of a process object ''' method = 'spawn' def __init__(self, process_obj): prep_data = spawn.get_preparation_data(process_obj._name) # read end of pipe will be duplicated by the child process # -- see spawn_main() in spawn.py. # # bpo-33929: Previously, the read end of pipe was "stolen" by the child # process, but it leaked a handle if the child process had been # terminated before it could steal the handle from the parent process. rhandle, whandle = _winapi.CreatePipe(None, 0) wfd = msvcrt.open_osfhandle(whandle, 0) cmd = spawn.get_command_line(parent_pid=os.getpid(), pipe_handle=rhandle) python_exe = spawn.get_executable() # bpo-35797: When running in a venv, we bypass the redirect # executor and launch our base Python. if WINENV and _path_eq(python_exe, sys.executable): cmd[0] = python_exe = sys._base_executable env = os.environ.copy() env["__PYVENV_LAUNCHER__"] = sys.executable else: env = None cmd = ' '.join('"%s"' % x for x in cmd) with open(wfd, 'wb', closefd=True) as to_child: # start process try: hp, ht, pid, tid = _winapi.CreateProcess( python_exe, cmd, None, None, False, 0, env, None, None) _winapi.CloseHandle(ht) except: _winapi.CloseHandle(rhandle) raise # set attributes of self self.pid = pid self.returncode = None self._handle = hp self.sentinel = int(hp) self.finalizer = util.Finalize(self, _close_handles, (self.sentinel, int(rhandle))) # send information to child set_spawning_popen(self) try: reduction.dump(prep_data, to_child) reduction.dump(process_obj, to_child) finally: set_spawning_popen(None) def duplicate_for_child(self, handle): assert self is get_spawning_popen() return reduction.duplicate(handle, self.sentinel) def wait(self, timeout=None): if self.returncode is not None: return self.returncode if timeout is None: msecs = _winapi.INFINITE else: msecs = max(0, int(timeout * 1000 + 0.5)) res = _winapi.WaitForSingleObject(int(self._handle), msecs) if res == _winapi.WAIT_OBJECT_0: code = _winapi.GetExitCodeProcess(self._handle) if code == TERMINATE: code = -signal.SIGTERM self.returncode = code return self.returncode def poll(self): return self.wait(timeout=0) def terminate(self): if self.returncode is not None: return try: _winapi.TerminateProcess(int(self._handle), TERMINATE) except PermissionError: # ERROR_ACCESS_DENIED (winerror 5) is received when the # process already died. code = _winapi.GetExitCodeProcess(int(self._handle)) if code == _winapi.STILL_ACTIVE: raise # gh-113009: Don't set self.returncode. Even if GetExitCodeProcess() # returns an exit code different than STILL_ACTIVE, the process can # still be running. Only set self.returncode once WaitForSingleObject() # returns WAIT_OBJECT_0 in wait(). kill = terminate def close(self): self.finalizer()