Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 1 | # |
| 2 | # Module for starting a process object using os.fork() or CreateProcess() |
| 3 | # |
| 4 | # multiprocessing/forking.py |
| 5 | # |
R. David Murray | 3fc969a | 2010-12-14 01:38:16 +0000 | [diff] [blame] | 6 | # Copyright (c) 2006-2008, R Oudkerk |
| 7 | # All rights reserved. |
| 8 | # |
| 9 | # Redistribution and use in source and binary forms, with or without |
| 10 | # modification, are permitted provided that the following conditions |
| 11 | # are met: |
| 12 | # |
| 13 | # 1. Redistributions of source code must retain the above copyright |
| 14 | # notice, this list of conditions and the following disclaimer. |
| 15 | # 2. Redistributions in binary form must reproduce the above copyright |
| 16 | # notice, this list of conditions and the following disclaimer in the |
| 17 | # documentation and/or other materials provided with the distribution. |
| 18 | # 3. Neither the name of author nor the names of any contributors may be |
| 19 | # used to endorse or promote products derived from this software |
| 20 | # without specific prior written permission. |
| 21 | # |
| 22 | # THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND |
| 23 | # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 24 | # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 25 | # ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| 26 | # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 27 | # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 28 | # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 29 | # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 30 | # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 31 | # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 32 | # SUCH DAMAGE. |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 33 | # |
| 34 | |
| 35 | import os |
| 36 | import sys |
| 37 | import signal |
Antoine Pitrou | dd69649 | 2011-06-08 17:21:55 +0200 | [diff] [blame] | 38 | import select |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 39 | |
| 40 | from multiprocessing import util, process |
| 41 | |
Amaury Forgeot d'Arc | 949d47d | 2008-08-19 21:30:55 +0000 | [diff] [blame] | 42 | __all__ = ['Popen', 'assert_spawning', 'exit', 'duplicate', 'close', 'ForkingPickler'] |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 43 | |
| 44 | # |
| 45 | # Check that the current thread is spawning a child process |
| 46 | # |
| 47 | |
| 48 | def assert_spawning(self): |
| 49 | if not Popen.thread_is_spawning(): |
| 50 | raise RuntimeError( |
| 51 | '%s objects should only be shared between processes' |
| 52 | ' through inheritance' % type(self).__name__ |
| 53 | ) |
| 54 | |
| 55 | # |
Amaury Forgeot d'Arc | 949d47d | 2008-08-19 21:30:55 +0000 | [diff] [blame] | 56 | # Try making some callable types picklable |
| 57 | # |
| 58 | |
| 59 | from pickle import _Pickler as Pickler |
| 60 | class ForkingPickler(Pickler): |
| 61 | dispatch = Pickler.dispatch.copy() |
| 62 | @classmethod |
| 63 | def register(cls, type, reduce): |
| 64 | def dispatcher(self, obj): |
| 65 | rv = reduce(obj) |
| 66 | if isinstance(rv, str): |
| 67 | self.save_global(obj, rv) |
| 68 | else: |
| 69 | self.save_reduce(obj=obj, *rv) |
| 70 | cls.dispatch[type] = dispatcher |
| 71 | |
| 72 | def _reduce_method(m): |
| 73 | if m.__self__ is None: |
| 74 | return getattr, (m.__class__, m.__func__.__name__) |
| 75 | else: |
| 76 | return getattr, (m.__self__, m.__func__.__name__) |
| 77 | class _C: |
| 78 | def f(self): |
| 79 | pass |
| 80 | ForkingPickler.register(type(_C().f), _reduce_method) |
| 81 | |
| 82 | |
| 83 | def _reduce_method_descriptor(m): |
| 84 | return getattr, (m.__objclass__, m.__name__) |
| 85 | ForkingPickler.register(type(list.append), _reduce_method_descriptor) |
| 86 | ForkingPickler.register(type(int.__add__), _reduce_method_descriptor) |
| 87 | |
| 88 | try: |
| 89 | from functools import partial |
| 90 | except ImportError: |
| 91 | pass |
| 92 | else: |
| 93 | def _reduce_partial(p): |
| 94 | return _rebuild_partial, (p.func, p.args, p.keywords or {}) |
| 95 | def _rebuild_partial(func, args, keywords): |
| 96 | return partial(func, *args, **keywords) |
| 97 | ForkingPickler.register(partial, _reduce_partial) |
| 98 | |
| 99 | # |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 100 | # Unix |
| 101 | # |
| 102 | |
| 103 | if sys.platform != 'win32': |
| 104 | import time |
Antoine Pitrou | 176f07d | 2011-06-06 19:35:31 +0200 | [diff] [blame] | 105 | import select |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 106 | |
| 107 | exit = os._exit |
| 108 | duplicate = os.dup |
| 109 | close = os.close |
Antoine Pitrou | 176f07d | 2011-06-06 19:35:31 +0200 | [diff] [blame] | 110 | _select = util._eintr_retry(select.select) |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 111 | |
| 112 | # |
| 113 | # We define a Popen class similar to the one from subprocess, but |
| 114 | # whose constructor takes a process object as its argument. |
| 115 | # |
| 116 | |
| 117 | class Popen(object): |
| 118 | |
| 119 | def __init__(self, process_obj): |
| 120 | sys.stdout.flush() |
| 121 | sys.stderr.flush() |
| 122 | self.returncode = None |
| 123 | |
Antoine Pitrou | 176f07d | 2011-06-06 19:35:31 +0200 | [diff] [blame] | 124 | r, w = os.pipe() |
| 125 | self.sentinel = r |
| 126 | |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 127 | self.pid = os.fork() |
| 128 | if self.pid == 0: |
Antoine Pitrou | 176f07d | 2011-06-06 19:35:31 +0200 | [diff] [blame] | 129 | os.close(r) |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 130 | if 'random' in sys.modules: |
| 131 | import random |
| 132 | random.seed() |
| 133 | code = process_obj._bootstrap() |
| 134 | sys.stdout.flush() |
| 135 | sys.stderr.flush() |
| 136 | os._exit(code) |
| 137 | |
Antoine Pitrou | 176f07d | 2011-06-06 19:35:31 +0200 | [diff] [blame] | 138 | # `w` will be closed when the child exits, at which point `r` |
| 139 | # will become ready for reading (using e.g. select()). |
| 140 | os.close(w) |
| 141 | util.Finalize(self, os.close, (r,)) |
| 142 | |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 143 | def poll(self, flag=os.WNOHANG): |
| 144 | if self.returncode is None: |
Florent Xicluna | 998171f | 2010-03-08 13:32:17 +0000 | [diff] [blame] | 145 | try: |
| 146 | pid, sts = os.waitpid(self.pid, flag) |
| 147 | except os.error: |
| 148 | # Child process not yet created. See #1731717 |
| 149 | # e.errno == errno.ECHILD == 10 |
| 150 | return None |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 151 | if pid == self.pid: |
| 152 | if os.WIFSIGNALED(sts): |
| 153 | self.returncode = -os.WTERMSIG(sts) |
| 154 | else: |
| 155 | assert os.WIFEXITED(sts) |
| 156 | self.returncode = os.WEXITSTATUS(sts) |
| 157 | return self.returncode |
| 158 | |
| 159 | def wait(self, timeout=None): |
Antoine Pitrou | 176f07d | 2011-06-06 19:35:31 +0200 | [diff] [blame] | 160 | if self.returncode is None: |
| 161 | if timeout is not None: |
| 162 | r = _select([self.sentinel], [], [], timeout)[0] |
| 163 | if not r: |
| 164 | return None |
| 165 | # This shouldn't block if select() returned successfully. |
| 166 | return self.poll(os.WNOHANG if timeout == 0.0 else 0) |
| 167 | return self.returncode |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 168 | |
| 169 | def terminate(self): |
| 170 | if self.returncode is None: |
| 171 | try: |
| 172 | os.kill(self.pid, signal.SIGTERM) |
| 173 | except OSError as e: |
| 174 | if self.wait(timeout=0.1) is None: |
| 175 | raise |
| 176 | |
| 177 | @staticmethod |
| 178 | def thread_is_spawning(): |
| 179 | return False |
| 180 | |
| 181 | # |
| 182 | # Windows |
| 183 | # |
| 184 | |
| 185 | else: |
| 186 | import _thread |
| 187 | import msvcrt |
| 188 | import _subprocess |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 189 | import time |
| 190 | |
Jesse Noller | f70a538 | 2009-01-18 19:44:02 +0000 | [diff] [blame] | 191 | from pickle import dump, load, HIGHEST_PROTOCOL |
Antoine Pitrou | 87cf220 | 2011-05-09 17:04:27 +0200 | [diff] [blame] | 192 | from _multiprocessing import win32 |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 193 | from .util import Finalize |
| 194 | |
Amaury Forgeot d'Arc | 949d47d | 2008-08-19 21:30:55 +0000 | [diff] [blame] | 195 | def dump(obj, file, protocol=None): |
| 196 | ForkingPickler(file, protocol).dump(obj) |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 197 | |
| 198 | # |
| 199 | # |
| 200 | # |
| 201 | |
| 202 | TERMINATE = 0x10000 |
| 203 | WINEXE = (sys.platform == 'win32' and getattr(sys, 'frozen', False)) |
brian.curtin | e2f2998 | 2011-04-11 17:56:23 -0500 | [diff] [blame] | 204 | WINSERVICE = sys.executable.lower().endswith("pythonservice.exe") |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 205 | |
| 206 | exit = win32.ExitProcess |
| 207 | close = win32.CloseHandle |
| 208 | |
| 209 | # |
| 210 | # _python_exe is the assumed path to the python executable. |
| 211 | # People embedding Python want to modify it. |
| 212 | # |
| 213 | |
brian.curtin | e2f2998 | 2011-04-11 17:56:23 -0500 | [diff] [blame] | 214 | if WINSERVICE: |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 215 | _python_exe = os.path.join(sys.exec_prefix, 'python.exe') |
| 216 | else: |
| 217 | _python_exe = sys.executable |
| 218 | |
| 219 | def set_executable(exe): |
| 220 | global _python_exe |
| 221 | _python_exe = exe |
| 222 | |
| 223 | # |
| 224 | # |
| 225 | # |
| 226 | |
| 227 | def duplicate(handle, target_process=None, inheritable=False): |
| 228 | if target_process is None: |
| 229 | target_process = _subprocess.GetCurrentProcess() |
| 230 | return _subprocess.DuplicateHandle( |
| 231 | _subprocess.GetCurrentProcess(), handle, target_process, |
| 232 | 0, inheritable, _subprocess.DUPLICATE_SAME_ACCESS |
| 233 | ).Detach() |
| 234 | |
| 235 | # |
| 236 | # We define a Popen class similar to the one from subprocess, but |
| 237 | # whose constructor takes a process object as its argument. |
| 238 | # |
| 239 | |
| 240 | class Popen(object): |
| 241 | ''' |
| 242 | Start a subprocess to run the code of a process object |
| 243 | ''' |
| 244 | _tls = _thread._local() |
| 245 | |
| 246 | def __init__(self, process_obj): |
| 247 | # create pipe for communication with child |
| 248 | rfd, wfd = os.pipe() |
| 249 | |
| 250 | # get handle for read end of the pipe and make it inheritable |
| 251 | rhandle = duplicate(msvcrt.get_osfhandle(rfd), inheritable=True) |
| 252 | os.close(rfd) |
| 253 | |
| 254 | # start process |
| 255 | cmd = get_command_line() + [rhandle] |
| 256 | cmd = ' '.join('"%s"' % x for x in cmd) |
| 257 | hp, ht, pid, tid = _subprocess.CreateProcess( |
| 258 | _python_exe, cmd, None, None, 1, 0, None, None, None |
| 259 | ) |
| 260 | ht.Close() |
| 261 | close(rhandle) |
| 262 | |
| 263 | # set attributes of self |
| 264 | self.pid = pid |
| 265 | self.returncode = None |
| 266 | self._handle = hp |
Antoine Pitrou | 176f07d | 2011-06-06 19:35:31 +0200 | [diff] [blame] | 267 | self.sentinel = int(hp) |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 268 | |
| 269 | # send information to child |
| 270 | prep_data = get_preparation_data(process_obj._name) |
| 271 | to_child = os.fdopen(wfd, 'wb') |
| 272 | Popen._tls.process_handle = int(hp) |
| 273 | try: |
| 274 | dump(prep_data, to_child, HIGHEST_PROTOCOL) |
| 275 | dump(process_obj, to_child, HIGHEST_PROTOCOL) |
| 276 | finally: |
| 277 | del Popen._tls.process_handle |
| 278 | to_child.close() |
| 279 | |
| 280 | @staticmethod |
| 281 | def thread_is_spawning(): |
| 282 | return getattr(Popen._tls, 'process_handle', None) is not None |
| 283 | |
| 284 | @staticmethod |
| 285 | def duplicate_for_child(handle): |
| 286 | return duplicate(handle, Popen._tls.process_handle) |
| 287 | |
| 288 | def wait(self, timeout=None): |
| 289 | if self.returncode is None: |
| 290 | if timeout is None: |
| 291 | msecs = _subprocess.INFINITE |
| 292 | else: |
| 293 | msecs = max(0, int(timeout * 1000 + 0.5)) |
| 294 | |
| 295 | res = _subprocess.WaitForSingleObject(int(self._handle), msecs) |
| 296 | if res == _subprocess.WAIT_OBJECT_0: |
| 297 | code = _subprocess.GetExitCodeProcess(self._handle) |
| 298 | if code == TERMINATE: |
| 299 | code = -signal.SIGTERM |
| 300 | self.returncode = code |
| 301 | |
| 302 | return self.returncode |
| 303 | |
| 304 | def poll(self): |
| 305 | return self.wait(timeout=0) |
| 306 | |
| 307 | def terminate(self): |
| 308 | if self.returncode is None: |
| 309 | try: |
| 310 | _subprocess.TerminateProcess(int(self._handle), TERMINATE) |
| 311 | except WindowsError: |
| 312 | if self.wait(timeout=0.1) is None: |
| 313 | raise |
| 314 | |
| 315 | # |
| 316 | # |
| 317 | # |
| 318 | |
| 319 | def is_forking(argv): |
| 320 | ''' |
| 321 | Return whether commandline indicates we are forking |
| 322 | ''' |
| 323 | if len(argv) >= 2 and argv[1] == '--multiprocessing-fork': |
| 324 | assert len(argv) == 3 |
| 325 | return True |
| 326 | else: |
| 327 | return False |
| 328 | |
| 329 | |
| 330 | def freeze_support(): |
| 331 | ''' |
| 332 | Run code for process object if this in not the main process |
| 333 | ''' |
| 334 | if is_forking(sys.argv): |
| 335 | main() |
| 336 | sys.exit() |
| 337 | |
| 338 | |
| 339 | def get_command_line(): |
| 340 | ''' |
| 341 | Returns prefix of command line used for spawning a child process |
| 342 | ''' |
| 343 | if process.current_process()._identity==() and is_forking(sys.argv): |
| 344 | raise RuntimeError(''' |
| 345 | Attempt to start a new process before the current process |
| 346 | has finished its bootstrapping phase. |
| 347 | |
| 348 | This probably means that you are on Windows and you have |
| 349 | forgotten to use the proper idiom in the main module: |
| 350 | |
| 351 | if __name__ == '__main__': |
| 352 | freeze_support() |
| 353 | ... |
| 354 | |
| 355 | The "freeze_support()" line can be omitted if the program |
| 356 | is not going to be frozen to produce a Windows executable.''') |
| 357 | |
| 358 | if getattr(sys, 'frozen', False): |
| 359 | return [sys.executable, '--multiprocessing-fork'] |
| 360 | else: |
| 361 | prog = 'from multiprocessing.forking import main; main()' |
| 362 | return [_python_exe, '-c', prog, '--multiprocessing-fork'] |
| 363 | |
| 364 | |
| 365 | def main(): |
| 366 | ''' |
| 367 | Run code specifed by data received over pipe |
| 368 | ''' |
| 369 | assert is_forking(sys.argv) |
| 370 | |
| 371 | handle = int(sys.argv[-1]) |
| 372 | fd = msvcrt.open_osfhandle(handle, os.O_RDONLY) |
| 373 | from_parent = os.fdopen(fd, 'rb') |
| 374 | |
| 375 | process.current_process()._inheriting = True |
| 376 | preparation_data = load(from_parent) |
| 377 | prepare(preparation_data) |
| 378 | self = load(from_parent) |
| 379 | process.current_process()._inheriting = False |
| 380 | |
| 381 | from_parent.close() |
| 382 | |
| 383 | exitcode = self._bootstrap() |
| 384 | exit(exitcode) |
| 385 | |
| 386 | |
| 387 | def get_preparation_data(name): |
| 388 | ''' |
| 389 | Return info about parent needed by child to unpickle process object |
| 390 | ''' |
| 391 | from .util import _logger, _log_to_stderr |
| 392 | |
| 393 | d = dict( |
| 394 | name=name, |
| 395 | sys_path=sys.path, |
| 396 | sys_argv=sys.argv, |
| 397 | log_to_stderr=_log_to_stderr, |
| 398 | orig_dir=process.ORIGINAL_DIR, |
Benjamin Peterson | 58ea9fe | 2008-08-19 19:17:39 +0000 | [diff] [blame] | 399 | authkey=process.current_process().authkey, |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 400 | ) |
| 401 | |
| 402 | if _logger is not None: |
| 403 | d['log_level'] = _logger.getEffectiveLevel() |
| 404 | |
brian.curtin | e2f2998 | 2011-04-11 17:56:23 -0500 | [diff] [blame] | 405 | if not WINEXE and not WINSERVICE: |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 406 | main_path = getattr(sys.modules['__main__'], '__file__', None) |
| 407 | if not main_path and sys.argv[0] not in ('', '-c'): |
| 408 | main_path = sys.argv[0] |
| 409 | if main_path is not None: |
| 410 | if not os.path.isabs(main_path) and \ |
| 411 | process.ORIGINAL_DIR is not None: |
| 412 | main_path = os.path.join(process.ORIGINAL_DIR, main_path) |
| 413 | d['main_path'] = os.path.normpath(main_path) |
| 414 | |
| 415 | return d |
| 416 | |
| 417 | # |
| 418 | # Make (Pipe)Connection picklable |
| 419 | # |
| 420 | |
Antoine Pitrou | 87cf220 | 2011-05-09 17:04:27 +0200 | [diff] [blame] | 421 | # Late import because of circular import |
| 422 | from .connection import Connection, PipeConnection |
| 423 | |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 424 | def reduce_connection(conn): |
| 425 | if not Popen.thread_is_spawning(): |
| 426 | raise RuntimeError( |
| 427 | 'By default %s objects can only be shared between processes\n' |
| 428 | 'using inheritance' % type(conn).__name__ |
| 429 | ) |
| 430 | return type(conn), (Popen.duplicate_for_child(conn.fileno()), |
| 431 | conn.readable, conn.writable) |
| 432 | |
Amaury Forgeot d'Arc | 949d47d | 2008-08-19 21:30:55 +0000 | [diff] [blame] | 433 | ForkingPickler.register(Connection, reduce_connection) |
| 434 | ForkingPickler.register(PipeConnection, reduce_connection) |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 435 | |
| 436 | # |
| 437 | # Prepare current process |
| 438 | # |
| 439 | |
| 440 | old_main_modules = [] |
| 441 | |
| 442 | def prepare(data): |
| 443 | ''' |
| 444 | Try to get current process ready to unpickle process object |
| 445 | ''' |
| 446 | old_main_modules.append(sys.modules['__main__']) |
| 447 | |
| 448 | if 'name' in data: |
Benjamin Peterson | 58ea9fe | 2008-08-19 19:17:39 +0000 | [diff] [blame] | 449 | process.current_process().name = data['name'] |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 450 | |
| 451 | if 'authkey' in data: |
| 452 | process.current_process()._authkey = data['authkey'] |
| 453 | |
| 454 | if 'log_to_stderr' in data and data['log_to_stderr']: |
| 455 | util.log_to_stderr() |
| 456 | |
| 457 | if 'log_level' in data: |
| 458 | util.get_logger().setLevel(data['log_level']) |
| 459 | |
| 460 | if 'sys_path' in data: |
| 461 | sys.path = data['sys_path'] |
| 462 | |
| 463 | if 'sys_argv' in data: |
| 464 | sys.argv = data['sys_argv'] |
| 465 | |
| 466 | if 'dir' in data: |
| 467 | os.chdir(data['dir']) |
| 468 | |
| 469 | if 'orig_dir' in data: |
| 470 | process.ORIGINAL_DIR = data['orig_dir'] |
| 471 | |
| 472 | if 'main_path' in data: |
Nick Coghlan | 793ee1f | 2011-01-30 01:24:08 +0000 | [diff] [blame] | 473 | # XXX (ncoghlan): The following code makes several bogus |
| 474 | # assumptions regarding the relationship between __file__ |
| 475 | # and a module's real name. See PEP 302 and issue #10845 |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 476 | main_path = data['main_path'] |
| 477 | main_name = os.path.splitext(os.path.basename(main_path))[0] |
| 478 | if main_name == '__init__': |
| 479 | main_name = os.path.basename(os.path.dirname(main_path)) |
| 480 | |
Nick Coghlan | 793ee1f | 2011-01-30 01:24:08 +0000 | [diff] [blame] | 481 | if main_name == '__main__': |
| 482 | main_module = sys.modules['__main__'] |
| 483 | main_module.__file__ = main_path |
| 484 | elif main_name != 'ipython': |
| 485 | # Main modules not actually called __main__.py may |
| 486 | # contain additional code that should still be executed |
Benjamin Peterson | e711caf | 2008-06-11 16:44:04 +0000 | [diff] [blame] | 487 | import imp |
| 488 | |
| 489 | if main_path is None: |
| 490 | dirs = None |
| 491 | elif os.path.basename(main_path).startswith('__init__.py'): |
| 492 | dirs = [os.path.dirname(os.path.dirname(main_path))] |
| 493 | else: |
| 494 | dirs = [os.path.dirname(main_path)] |
| 495 | |
| 496 | assert main_name not in sys.modules, main_name |
| 497 | file, path_name, etc = imp.find_module(main_name, dirs) |
| 498 | try: |
| 499 | # We would like to do "imp.load_module('__main__', ...)" |
| 500 | # here. However, that would cause 'if __name__ == |
| 501 | # "__main__"' clauses to be executed. |
| 502 | main_module = imp.load_module( |
| 503 | '__parents_main__', file, path_name, etc |
| 504 | ) |
| 505 | finally: |
| 506 | if file: |
| 507 | file.close() |
| 508 | |
| 509 | sys.modules['__main__'] = main_module |
| 510 | main_module.__name__ = '__main__' |
| 511 | |
| 512 | # Try to make the potentially picklable objects in |
| 513 | # sys.modules['__main__'] realize they are in the main |
| 514 | # module -- somewhat ugly. |
| 515 | for obj in list(main_module.__dict__.values()): |
| 516 | try: |
| 517 | if obj.__module__ == '__parents_main__': |
| 518 | obj.__module__ = '__main__' |
| 519 | except Exception: |
| 520 | pass |