From 7f8bfc9b9a8381ddb768421b5dd5cbd970266190 Mon Sep 17 00:00:00 2001 From: Eric Snow Date: Mon, 29 Jan 2018 18:23:44 -0700 Subject: [PATCH] bpo-32604: Expose the subinterpreters C-API in a "private" stdlib module. (gh-1748) The module is primarily intended for internal use in the test suite. Building the module under Windows will come in a follow-up PR. --- Include/internal/pystate.h | 78 + Lib/test/test__xxsubinterpreters.py | 1118 +++++++++ .../2018-01-26-21-29-09.bpo-32604.7iazNx.rst | 4 + Modules/_xxsubinterpretersmodule.c | 2061 +++++++++++++++++ Python/pystate.c | 275 ++- setup.py | 4 + 6 files changed, 3539 insertions(+), 1 deletion(-) create mode 100644 Lib/test/test__xxsubinterpreters.py create mode 100644 Misc/NEWS.d/next/Tests/2018-01-26-21-29-09.bpo-32604.7iazNx.rst create mode 100644 Modules/_xxsubinterpretersmodule.c diff --git a/Include/internal/pystate.h b/Include/internal/pystate.h index 0b464bcb2e8..2b60b25c19b 100644 --- a/Include/internal/pystate.h +++ b/Include/internal/pystate.h @@ -65,6 +65,79 @@ PyAPI_FUNC(_PyInitError) _PyPathConfig_Calculate( PyAPI_FUNC(void) _PyPathConfig_Clear(_PyPathConfig *config); +/* interpreter state */ + +PyAPI_FUNC(PyInterpreterState *) _PyInterpreterState_LookUpID(PY_INT64_T); + + +/* cross-interpreter data */ + +struct _xid; + +// _PyCrossInterpreterData is similar to Py_buffer as an effectively +// opaque struct that holds data outside the object machinery. This +// is necessary to pass between interpreters in the same process. +typedef struct _xid { + // data is the cross-interpreter-safe derivation of a Python object + // (see _PyObject_GetCrossInterpreterData). It will be NULL if the + // new_object func (below) encodes the data. + void *data; + // obj is the Python object from which the data was derived. This + // is non-NULL only if the data remains bound to the object in some + // way, such that the object must be "released" (via a decref) when + // the data is released. In that case it is automatically + // incref'ed (to match the automatic decref when releaed). + PyObject *obj; + // interp is the ID of the owning interpreter of the original + // object. It corresponds to the active interpreter when + // _PyObject_GetCrossInterpreterData() was called. This should only + // be set by the cross-interpreter machinery. + // + // We use the ID rather than the PyInterpreterState to avoid issues + // with deleted interpreters. + int64_t interp; + // new_object is a function that returns a new object in the current + // interpreter given the data. The resulting object (a new + // reference) will be equivalent to the original object. This field + // is required. + PyObject *(*new_object)(struct _xid *); + // free is called when the data is released. If it is NULL then + // nothing will be done to free the data. For some types this is + // okay (e.g. bytes) and for those types this field should be set + // to NULL. However, for most the data was allocated just for + // cross-interpreter use, so it must be freed when + // _PyCrossInterpreterData_Release is called or the memory will + // leak. In that case, at the very least this field should be set + // to PyMem_RawFree (the default if not explicitly set to NULL). + // The call will happen with the original interpreter activated. + void (*free)(void *); +} _PyCrossInterpreterData; + +typedef int (*crossinterpdatafunc)(PyObject *, _PyCrossInterpreterData *); +PyAPI_FUNC(int) _PyObject_CheckCrossInterpreterData(PyObject *); + +PyAPI_FUNC(int) _PyObject_GetCrossInterpreterData(PyObject *, _PyCrossInterpreterData *); +PyAPI_FUNC(PyObject *) _PyCrossInterpreterData_NewObject(_PyCrossInterpreterData *); +PyAPI_FUNC(void) _PyCrossInterpreterData_Release(_PyCrossInterpreterData *); + +/* cross-interpreter data registry */ + +/* For now we use a global registry of shareable classes. An + alternative would be to add a tp_* slot for a class's + crossinterpdatafunc. It would be simpler and more efficient. */ + +PyAPI_FUNC(int) _PyCrossInterpreterData_Register_Class(PyTypeObject *, crossinterpdatafunc); +PyAPI_FUNC(crossinterpdatafunc) _PyCrossInterpreterData_Lookup(PyObject *); + +struct _xidregitem; + +struct _xidregitem { + PyTypeObject *cls; + crossinterpdatafunc getdata; + struct _xidregitem *next; +}; + + /* Full Python runtime state */ typedef struct pyruntimestate { @@ -86,6 +159,11 @@ typedef struct pyruntimestate { using a Python int. */ int64_t next_id; } interpreters; + // XXX Remove this field once we have a tp_* slot. + struct _xidregistry { + PyThread_type_lock mutex; + struct _xidregitem *head; + } xidregistry; #define NEXITFUNCS 32 void (*exitfuncs[NEXITFUNCS])(void); diff --git a/Lib/test/test__xxsubinterpreters.py b/Lib/test/test__xxsubinterpreters.py new file mode 100644 index 00000000000..2b170443a3b --- /dev/null +++ b/Lib/test/test__xxsubinterpreters.py @@ -0,0 +1,1118 @@ +import contextlib +import os +import pickle +from textwrap import dedent, indent +import threading +import unittest + +from test import support +from test.support import script_helper + +interpreters = support.import_module('_xxsubinterpreters') + + +def _captured_script(script): + r, w = os.pipe() + indented = script.replace('\n', '\n ') + wrapped = dedent(f""" + import contextlib + with open({w}, 'w') as chan: + with contextlib.redirect_stdout(chan): + {indented} + """) + return wrapped, open(r) + + +def _run_output(interp, request, shared=None): + script, chan = _captured_script(request) + with chan: + interpreters.run_string(interp, script, shared) + return chan.read() + + +@contextlib.contextmanager +def _running(interp): + r, w = os.pipe() + def run(): + interpreters.run_string(interp, dedent(f""" + # wait for "signal" + with open({r}) as chan: + chan.read() + """)) + + t = threading.Thread(target=run) + t.start() + + yield + + with open(w, 'w') as chan: + chan.write('done') + t.join() + + +class IsShareableTests(unittest.TestCase): + + def test_default_shareables(self): + shareables = [ + # singletons + None, + # builtin objects + b'spam', + ] + for obj in shareables: + with self.subTest(obj): + self.assertTrue( + interpreters.is_shareable(obj)) + + def test_not_shareable(self): + class Cheese: + def __init__(self, name): + self.name = name + def __str__(self): + return self.name + + class SubBytes(bytes): + """A subclass of a shareable type.""" + + not_shareables = [ + # singletons + True, + False, + NotImplemented, + ..., + # builtin types and objects + type, + object, + object(), + Exception(), + 42, + 100.0, + 'spam', + # user-defined types and objects + Cheese, + Cheese('Wensleydale'), + SubBytes(b'spam'), + ] + for obj in not_shareables: + with self.subTest(obj): + self.assertFalse( + interpreters.is_shareable(obj)) + + +class TestBase(unittest.TestCase): + + def tearDown(self): + for id in interpreters.list_all(): + if id == 0: # main + continue + try: + interpreters.destroy(id) + except RuntimeError: + pass # already destroyed + + for cid in interpreters.channel_list_all(): + try: + interpreters.channel_destroy(cid) + except interpreters.ChannelNotFoundError: + pass # already destroyed + + +class ListAllTests(TestBase): + + def test_initial(self): + main = interpreters.get_main() + ids = interpreters.list_all() + self.assertEqual(ids, [main]) + + def test_after_creating(self): + main = interpreters.get_main() + first = interpreters.create() + second = interpreters.create() + ids = interpreters.list_all() + self.assertEqual(ids, [main, first, second]) + + def test_after_destroying(self): + main = interpreters.get_main() + first = interpreters.create() + second = interpreters.create() + interpreters.destroy(first) + ids = interpreters.list_all() + self.assertEqual(ids, [main, second]) + + +class GetCurrentTests(TestBase): + + def test_main(self): + main = interpreters.get_main() + cur = interpreters.get_current() + self.assertEqual(cur, main) + + def test_subinterpreter(self): + main = interpreters.get_main() + interp = interpreters.create() + out = _run_output(interp, dedent(""" + import _xxsubinterpreters as _interpreters + print(_interpreters.get_current()) + """)) + cur = int(out.strip()) + _, expected = interpreters.list_all() + self.assertEqual(cur, expected) + self.assertNotEqual(cur, main) + + +class GetMainTests(TestBase): + + def test_from_main(self): + [expected] = interpreters.list_all() + main = interpreters.get_main() + self.assertEqual(main, expected) + + def test_from_subinterpreter(self): + [expected] = interpreters.list_all() + interp = interpreters.create() + out = _run_output(interp, dedent(""" + import _xxsubinterpreters as _interpreters + print(_interpreters.get_main()) + """)) + main = int(out.strip()) + self.assertEqual(main, expected) + + +class IsRunningTests(TestBase): + + def test_main(self): + main = interpreters.get_main() + self.assertTrue(interpreters.is_running(main)) + + def test_subinterpreter(self): + interp = interpreters.create() + self.assertFalse(interpreters.is_running(interp)) + + with _running(interp): + self.assertTrue(interpreters.is_running(interp)) + self.assertFalse(interpreters.is_running(interp)) + + def test_from_subinterpreter(self): + interp = interpreters.create() + out = _run_output(interp, dedent(f""" + import _xxsubinterpreters as _interpreters + if _interpreters.is_running({interp}): + print(True) + else: + print(False) + """)) + self.assertEqual(out.strip(), 'True') + + def test_already_destroyed(self): + interp = interpreters.create() + interpreters.destroy(interp) + with self.assertRaises(RuntimeError): + interpreters.is_running(interp) + + def test_does_not_exist(self): + with self.assertRaises(RuntimeError): + interpreters.is_running(1_000_000) + + def test_bad_id(self): + with self.assertRaises(RuntimeError): + interpreters.is_running(-1) + + +class CreateTests(TestBase): + + def test_in_main(self): + id = interpreters.create() + + self.assertIn(id, interpreters.list_all()) + + @unittest.skip('enable this test when working on pystate.c') + def test_unique_id(self): + seen = set() + for _ in range(100): + id = interpreters.create() + interpreters.destroy(id) + seen.add(id) + + self.assertEqual(len(seen), 100) + + def test_in_thread(self): + lock = threading.Lock() + id = None + def f(): + nonlocal id + id = interpreters.create() + lock.acquire() + lock.release() + + t = threading.Thread(target=f) + with lock: + t.start() + t.join() + self.assertIn(id, interpreters.list_all()) + + def test_in_subinterpreter(self): + main, = interpreters.list_all() + id1 = interpreters.create() + out = _run_output(id1, dedent(""" + import _xxsubinterpreters as _interpreters + id = _interpreters.create() + print(id) + """)) + id2 = int(out.strip()) + + self.assertEqual(set(interpreters.list_all()), {main, id1, id2}) + + def test_in_threaded_subinterpreter(self): + main, = interpreters.list_all() + id1 = interpreters.create() + id2 = None + def f(): + nonlocal id2 + out = _run_output(id1, dedent(""" + import _xxsubinterpreters as _interpreters + id = _interpreters.create() + print(id) + """)) + id2 = int(out.strip()) + + t = threading.Thread(target=f) + t.start() + t.join() + + self.assertEqual(set(interpreters.list_all()), {main, id1, id2}) + + def test_after_destroy_all(self): + before = set(interpreters.list_all()) + # Create 3 subinterpreters. + ids = [] + for _ in range(3): + id = interpreters.create() + ids.append(id) + # Now destroy them. + for id in ids: + interpreters.destroy(id) + # Finally, create another. + id = interpreters.create() + self.assertEqual(set(interpreters.list_all()), before | {id}) + + def test_after_destroy_some(self): + before = set(interpreters.list_all()) + # Create 3 subinterpreters. + id1 = interpreters.create() + id2 = interpreters.create() + id3 = interpreters.create() + # Now destroy 2 of them. + interpreters.destroy(id1) + interpreters.destroy(id3) + # Finally, create another. + id = interpreters.create() + self.assertEqual(set(interpreters.list_all()), before | {id, id2}) + + +class DestroyTests(TestBase): + + def test_one(self): + id1 = interpreters.create() + id2 = interpreters.create() + id3 = interpreters.create() + self.assertIn(id2, interpreters.list_all()) + interpreters.destroy(id2) + self.assertNotIn(id2, interpreters.list_all()) + self.assertIn(id1, interpreters.list_all()) + self.assertIn(id3, interpreters.list_all()) + + def test_all(self): + before = set(interpreters.list_all()) + ids = set() + for _ in range(3): + id = interpreters.create() + ids.add(id) + self.assertEqual(set(interpreters.list_all()), before | ids) + for id in ids: + interpreters.destroy(id) + self.assertEqual(set(interpreters.list_all()), before) + + def test_main(self): + main, = interpreters.list_all() + with self.assertRaises(RuntimeError): + interpreters.destroy(main) + + def f(): + with self.assertRaises(RuntimeError): + interpreters.destroy(main) + + t = threading.Thread(target=f) + t.start() + t.join() + + def test_already_destroyed(self): + id = interpreters.create() + interpreters.destroy(id) + with self.assertRaises(RuntimeError): + interpreters.destroy(id) + + def test_does_not_exist(self): + with self.assertRaises(RuntimeError): + interpreters.destroy(1_000_000) + + def test_bad_id(self): + with self.assertRaises(RuntimeError): + interpreters.destroy(-1) + + def test_from_current(self): + main, = interpreters.list_all() + id = interpreters.create() + script = dedent(""" + import _xxsubinterpreters as _interpreters + _interpreters.destroy({}) + """).format(id) + + with self.assertRaises(RuntimeError): + interpreters.run_string(id, script) + self.assertEqual(set(interpreters.list_all()), {main, id}) + + def test_from_sibling(self): + main, = interpreters.list_all() + id1 = interpreters.create() + id2 = interpreters.create() + script = dedent(""" + import _xxsubinterpreters as _interpreters + _interpreters.destroy({}) + """).format(id2) + interpreters.run_string(id1, script) + + self.assertEqual(set(interpreters.list_all()), {main, id1}) + + def test_from_other_thread(self): + id = interpreters.create() + def f(): + interpreters.destroy(id) + + t = threading.Thread(target=f) + t.start() + t.join() + + def test_still_running(self): + main, = interpreters.list_all() + interp = interpreters.create() + with _running(interp): + with self.assertRaises(RuntimeError): + interpreters.destroy(interp) + self.assertTrue(interpreters.is_running(interp)) + + +class RunStringTests(TestBase): + + SCRIPT = dedent(""" + with open('{}', 'w') as out: + out.write('{}') + """) + FILENAME = 'spam' + + def setUp(self): + super().setUp() + self.id = interpreters.create() + self._fs = None + + def tearDown(self): + if self._fs is not None: + self._fs.close() + super().tearDown() + + @property + def fs(self): + if self._fs is None: + self._fs = FSFixture(self) + return self._fs + + def test_success(self): + script, file = _captured_script('print("it worked!", end="")') + with file: + interpreters.run_string(self.id, script) + out = file.read() + + self.assertEqual(out, 'it worked!') + + def test_in_thread(self): + script, file = _captured_script('print("it worked!", end="")') + with file: + def f(): + interpreters.run_string(self.id, script) + + t = threading.Thread(target=f) + t.start() + t.join() + out = file.read() + + self.assertEqual(out, 'it worked!') + + def test_create_thread(self): + script, file = _captured_script(""" + import threading + def f(): + print('it worked!', end='') + + t = threading.Thread(target=f) + t.start() + t.join() + """) + with file: + interpreters.run_string(self.id, script) + out = file.read() + + self.assertEqual(out, 'it worked!') + + @unittest.skipUnless(hasattr(os, 'fork'), "test needs os.fork()") + def test_fork(self): + import tempfile + with tempfile.NamedTemporaryFile('w+') as file: + file.write('') + file.flush() + + expected = 'spam spam spam spam spam' + script = dedent(f""" + # (inspired by Lib/test/test_fork.py) + import os + pid = os.fork() + if pid == 0: # child + with open('{file.name}', 'w') as out: + out.write('{expected}') + # Kill the unittest runner in the child process. + os._exit(1) + else: + SHORT_SLEEP = 0.1 + import time + for _ in range(10): + spid, status = os.waitpid(pid, os.WNOHANG) + if spid == pid: + break + time.sleep(SHORT_SLEEP) + assert(spid == pid) + """) + interpreters.run_string(self.id, script) + + file.seek(0) + content = file.read() + self.assertEqual(content, expected) + + def test_already_running(self): + with _running(self.id): + with self.assertRaises(RuntimeError): + interpreters.run_string(self.id, 'print("spam")') + + def test_does_not_exist(self): + id = 0 + while id in interpreters.list_all(): + id += 1 + with self.assertRaises(RuntimeError): + interpreters.run_string(id, 'print("spam")') + + def test_error_id(self): + with self.assertRaises(RuntimeError): + interpreters.run_string(-1, 'print("spam")') + + def test_bad_id(self): + with self.assertRaises(TypeError): + interpreters.run_string('spam', 'print("spam")') + + def test_bad_script(self): + with self.assertRaises(TypeError): + interpreters.run_string(self.id, 10) + + def test_bytes_for_script(self): + with self.assertRaises(TypeError): + interpreters.run_string(self.id, b'print("spam")') + + @contextlib.contextmanager + def assert_run_failed(self, exctype, msg=None): + with self.assertRaises(interpreters.RunFailedError) as caught: + yield + if msg is None: + self.assertEqual(str(caught.exception).split(':')[0], + str(exctype)) + else: + self.assertEqual(str(caught.exception), + "{}: {}".format(exctype, msg)) + + def test_invalid_syntax(self): + with self.assert_run_failed(SyntaxError): + # missing close paren + interpreters.run_string(self.id, 'print("spam"') + + def test_failure(self): + with self.assert_run_failed(Exception, 'spam'): + interpreters.run_string(self.id, 'raise Exception("spam")') + + def test_SystemExit(self): + with self.assert_run_failed(SystemExit, '42'): + interpreters.run_string(self.id, 'raise SystemExit(42)') + + def test_sys_exit(self): + with self.assert_run_failed(SystemExit): + interpreters.run_string(self.id, dedent(""" + import sys + sys.exit() + """)) + + with self.assert_run_failed(SystemExit, '42'): + interpreters.run_string(self.id, dedent(""" + import sys + sys.exit(42) + """)) + + def test_with_shared(self): + r, w = os.pipe() + + shared = { + 'spam': b'ham', + 'eggs': b'-1', + 'cheddar': None, + } + script = dedent(f""" + eggs = int(eggs) + spam = 42 + result = spam + eggs + + ns = dict(vars()) + del ns['__builtins__'] + import pickle + with open({w}, 'wb') as chan: + pickle.dump(ns, chan) + """) + interpreters.run_string(self.id, script, shared) + with open(r, 'rb') as chan: + ns = pickle.load(chan) + + self.assertEqual(ns['spam'], 42) + self.assertEqual(ns['eggs'], -1) + self.assertEqual(ns['result'], 41) + self.assertIsNone(ns['cheddar']) + + def test_shared_overwrites(self): + interpreters.run_string(self.id, dedent(""" + spam = 'eggs' + ns1 = dict(vars()) + del ns1['__builtins__'] + """)) + + shared = {'spam': b'ham'} + script = dedent(f""" + ns2 = dict(vars()) + del ns2['__builtins__'] + """) + interpreters.run_string(self.id, script, shared) + + r, w = os.pipe() + script = dedent(f""" + ns = dict(vars()) + del ns['__builtins__'] + import pickle + with open({w}, 'wb') as chan: + pickle.dump(ns, chan) + """) + interpreters.run_string(self.id, script) + with open(r, 'rb') as chan: + ns = pickle.load(chan) + + self.assertEqual(ns['ns1']['spam'], 'eggs') + self.assertEqual(ns['ns2']['spam'], b'ham') + self.assertEqual(ns['spam'], b'ham') + + def test_shared_overwrites_default_vars(self): + r, w = os.pipe() + + shared = {'__name__': b'not __main__'} + script = dedent(f""" + spam = 42 + + ns = dict(vars()) + del ns['__builtins__'] + import pickle + with open({w}, 'wb') as chan: + pickle.dump(ns, chan) + """) + interpreters.run_string(self.id, script, shared) + with open(r, 'rb') as chan: + ns = pickle.load(chan) + + self.assertEqual(ns['__name__'], b'not __main__') + + def test_main_reused(self): + r, w = os.pipe() + interpreters.run_string(self.id, dedent(f""" + spam = True + + ns = dict(vars()) + del ns['__builtins__'] + import pickle + with open({w}, 'wb') as chan: + pickle.dump(ns, chan) + del ns, pickle, chan + """)) + with open(r, 'rb') as chan: + ns1 = pickle.load(chan) + + r, w = os.pipe() + interpreters.run_string(self.id, dedent(f""" + eggs = False + + ns = dict(vars()) + del ns['__builtins__'] + import pickle + with open({w}, 'wb') as chan: + pickle.dump(ns, chan) + """)) + with open(r, 'rb') as chan: + ns2 = pickle.load(chan) + + self.assertIn('spam', ns1) + self.assertNotIn('eggs', ns1) + self.assertIn('eggs', ns2) + self.assertIn('spam', ns2) + + def test_execution_namespace_is_main(self): + r, w = os.pipe() + + script = dedent(f""" + spam = 42 + + ns = dict(vars()) + ns['__builtins__'] = str(ns['__builtins__']) + import pickle + with open({w}, 'wb') as chan: + pickle.dump(ns, chan) + """) + interpreters.run_string(self.id, script) + with open(r, 'rb') as chan: + ns = pickle.load(chan) + + ns.pop('__builtins__') + ns.pop('__loader__') + self.assertEqual(ns, { + '__name__': '__main__', + '__annotations__': {}, + '__doc__': None, + '__package__': None, + '__spec__': None, + 'spam': 42, + }) + + def test_still_running_at_exit(self): + script = dedent(f""" + from textwrap import dedent + import threading + import _xxsubinterpreters as _interpreters + def f(): + _interpreters.run_string(id, dedent(''' + import time + # Give plenty of time for the main interpreter to finish. + time.sleep(1_000_000) + ''')) + + t = threading.Thread(target=f) + t.start() + """) + with support.temp_dir() as dirname: + filename = script_helper.make_script(dirname, 'interp', script) + with script_helper.spawn_python(filename) as proc: + retcode = proc.wait() + + self.assertEqual(retcode, 0) + + +class ChannelIDTests(TestBase): + + def test_default_kwargs(self): + cid = interpreters._channel_id(10, force=True) + + self.assertEqual(int(cid), 10) + self.assertEqual(cid.end, 'both') + + def test_with_kwargs(self): + cid = interpreters._channel_id(10, send=True, force=True) + self.assertEqual(cid.end, 'send') + + cid = interpreters._channel_id(10, send=True, recv=False, force=True) + self.assertEqual(cid.end, 'send') + + cid = interpreters._channel_id(10, recv=True, force=True) + self.assertEqual(cid.end, 'recv') + + cid = interpreters._channel_id(10, recv=True, send=False, force=True) + self.assertEqual(cid.end, 'recv') + + cid = interpreters._channel_id(10, send=True, recv=True, force=True) + self.assertEqual(cid.end, 'both') + + def test_coerce_id(self): + cid = interpreters._channel_id('10', force=True) + self.assertEqual(int(cid), 10) + + cid = interpreters._channel_id(10.0, force=True) + self.assertEqual(int(cid), 10) + + class Int(str): + def __init__(self, value): + self._value = value + def __int__(self): + return self._value + + cid = interpreters._channel_id(Int(10), force=True) + self.assertEqual(int(cid), 10) + + def test_bad_id(self): + ids = [-1, 2**64, "spam"] + for cid in ids: + with self.subTest(cid): + with self.assertRaises(ValueError): + interpreters._channel_id(cid) + + with self.assertRaises(TypeError): + interpreters._channel_id(object()) + + def test_bad_kwargs(self): + with self.assertRaises(ValueError): + interpreters._channel_id(10, send=False, recv=False) + + def test_does_not_exist(self): + cid = interpreters.channel_create() + with self.assertRaises(interpreters.ChannelNotFoundError): + interpreters._channel_id(int(cid) + 1) # unforced + + def test_repr(self): + cid = interpreters._channel_id(10, force=True) + self.assertEqual(repr(cid), 'ChannelID(10)') + + cid = interpreters._channel_id(10, send=True, force=True) + self.assertEqual(repr(cid), 'ChannelID(10, send=True)') + + cid = interpreters._channel_id(10, recv=True, force=True) + self.assertEqual(repr(cid), 'ChannelID(10, recv=True)') + + cid = interpreters._channel_id(10, send=True, recv=True, force=True) + self.assertEqual(repr(cid), 'ChannelID(10)') + + def test_equality(self): + cid1 = interpreters.channel_create() + cid2 = interpreters._channel_id(int(cid1)) + cid3 = interpreters.channel_create() + + self.assertTrue(cid1 == cid1) + self.assertTrue(cid1 == cid2) + self.assertTrue(cid1 == int(cid1)) + self.assertFalse(cid1 == cid3) + + self.assertFalse(cid1 != cid1) + self.assertFalse(cid1 != cid2) + self.assertTrue(cid1 != cid3) + + +class ChannelTests(TestBase): + + def test_sequential_ids(self): + before = interpreters.channel_list_all() + id1 = interpreters.channel_create() + id2 = interpreters.channel_create() + id3 = interpreters.channel_create() + after = interpreters.channel_list_all() + + self.assertEqual(id2, int(id1) + 1) + self.assertEqual(id3, int(id2) + 1) + self.assertEqual(set(after) - set(before), {id1, id2, id3}) + + def test_ids_global(self): + id1 = interpreters.create() + out = _run_output(id1, dedent(""" + import _xxsubinterpreters as _interpreters + cid = _interpreters.channel_create() + print(int(cid)) + """)) + cid1 = int(out.strip()) + + id2 = interpreters.create() + out = _run_output(id2, dedent(""" + import _xxsubinterpreters as _interpreters + cid = _interpreters.channel_create() + print(int(cid)) + """)) + cid2 = int(out.strip()) + + self.assertEqual(cid2, int(cid1) + 1) + + #################### + + def test_drop_single_user(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interpreters.channel_recv(cid) + interpreters.channel_drop_interpreter(cid, send=True, recv=True) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_send(cid, b'eggs') + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + + def test_drop_multiple_users(self): + cid = interpreters.channel_create() + id1 = interpreters.create() + id2 = interpreters.create() + interpreters.run_string(id1, dedent(f""" + import _xxsubinterpreters as _interpreters + _interpreters.channel_send({int(cid)}, b'spam') + """)) + out = _run_output(id2, dedent(f""" + import _xxsubinterpreters as _interpreters + obj = _interpreters.channel_recv({int(cid)}) + _interpreters.channel_drop_interpreter({int(cid)}) + print(repr(obj)) + """)) + interpreters.run_string(id1, dedent(f""" + _interpreters.channel_drop_interpreter({int(cid)}) + """)) + + self.assertEqual(out.strip(), "b'spam'") + + def test_drop_no_kwargs(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interpreters.channel_recv(cid) + interpreters.channel_drop_interpreter(cid) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_send(cid, b'eggs') + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + + def test_drop_multiple_times(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interpreters.channel_recv(cid) + interpreters.channel_drop_interpreter(cid, send=True, recv=True) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_drop_interpreter(cid, send=True, recv=True) + + def test_drop_with_unused_items(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interpreters.channel_send(cid, b'ham') + interpreters.channel_drop_interpreter(cid, send=True, recv=True) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + + def test_drop_never_used(self): + cid = interpreters.channel_create() + interpreters.channel_drop_interpreter(cid) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_send(cid, b'spam') + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + + def test_drop_by_unassociated_interp(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interp = interpreters.create() + interpreters.run_string(interp, dedent(f""" + import _xxsubinterpreters as _interpreters + _interpreters.channel_drop_interpreter({int(cid)}) + """)) + obj = interpreters.channel_recv(cid) + interpreters.channel_drop_interpreter(cid) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_send(cid, b'eggs') + self.assertEqual(obj, b'spam') + + def test_drop_close_if_unassociated(self): + cid = interpreters.channel_create() + interp = interpreters.create() + interpreters.run_string(interp, dedent(f""" + import _xxsubinterpreters as _interpreters + obj = _interpreters.channel_send({int(cid)}, b'spam') + _interpreters.channel_drop_interpreter({int(cid)}) + """)) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + + def test_drop_partially(self): + # XXX Is partial close too wierd/confusing? + cid = interpreters.channel_create() + interpreters.channel_send(cid, None) + interpreters.channel_recv(cid) + interpreters.channel_send(cid, b'spam') + interpreters.channel_drop_interpreter(cid, send=True) + obj = interpreters.channel_recv(cid) + + self.assertEqual(obj, b'spam') + + def test_drop_used_multiple_times_by_single_user(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interpreters.channel_send(cid, b'spam') + interpreters.channel_send(cid, b'spam') + interpreters.channel_recv(cid) + interpreters.channel_drop_interpreter(cid, send=True, recv=True) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_send(cid, b'eggs') + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + + #################### + + def test_close_single_user(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interpreters.channel_recv(cid) + interpreters.channel_close(cid) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_send(cid, b'eggs') + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + + def test_close_multiple_users(self): + cid = interpreters.channel_create() + id1 = interpreters.create() + id2 = interpreters.create() + interpreters.run_string(id1, dedent(f""" + import _xxsubinterpreters as _interpreters + _interpreters.channel_send({int(cid)}, b'spam') + """)) + interpreters.run_string(id2, dedent(f""" + import _xxsubinterpreters as _interpreters + _interpreters.channel_recv({int(cid)}) + """)) + interpreters.channel_close(cid) + with self.assertRaises(interpreters.RunFailedError) as cm: + interpreters.run_string(id1, dedent(f""" + _interpreters.channel_send({int(cid)}, b'spam') + """)) + self.assertIn('ChannelClosedError', str(cm.exception)) + with self.assertRaises(interpreters.RunFailedError) as cm: + interpreters.run_string(id2, dedent(f""" + _interpreters.channel_send({int(cid)}, b'spam') + """)) + self.assertIn('ChannelClosedError', str(cm.exception)) + + def test_close_multiple_times(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interpreters.channel_recv(cid) + interpreters.channel_close(cid) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_close(cid) + + def test_close_with_unused_items(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interpreters.channel_send(cid, b'ham') + interpreters.channel_close(cid) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + + def test_close_never_used(self): + cid = interpreters.channel_create() + interpreters.channel_close(cid) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_send(cid, b'spam') + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + + def test_close_by_unassociated_interp(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interp = interpreters.create() + interpreters.run_string(interp, dedent(f""" + import _xxsubinterpreters as _interpreters + _interpreters.channel_close({int(cid)}) + """)) + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_close(cid) + + def test_close_used_multiple_times_by_single_user(self): + cid = interpreters.channel_create() + interpreters.channel_send(cid, b'spam') + interpreters.channel_send(cid, b'spam') + interpreters.channel_send(cid, b'spam') + interpreters.channel_recv(cid) + interpreters.channel_close(cid) + + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_send(cid, b'eggs') + with self.assertRaises(interpreters.ChannelClosedError): + interpreters.channel_recv(cid) + + #################### + + def test_send_recv_main(self): + cid = interpreters.channel_create() + orig = b'spam' + interpreters.channel_send(cid, orig) + obj = interpreters.channel_recv(cid) + + self.assertEqual(obj, orig) + self.assertIsNot(obj, orig) + + def test_send_recv_same_interpreter(self): + id1 = interpreters.create() + out = _run_output(id1, dedent(""" + import _xxsubinterpreters as _interpreters + cid = _interpreters.channel_create() + orig = b'spam' + _interpreters.channel_send(cid, orig) + obj = _interpreters.channel_recv(cid) + assert obj is not orig + assert obj == orig + """)) + + def test_send_recv_different_interpreters(self): + cid = interpreters.channel_create() + id1 = interpreters.create() + out = _run_output(id1, dedent(f""" + import _xxsubinterpreters as _interpreters + _interpreters.channel_send({int(cid)}, b'spam') + """)) + obj = interpreters.channel_recv(cid) + + self.assertEqual(obj, b'spam') + + def test_send_not_found(self): + with self.assertRaises(interpreters.ChannelNotFoundError): + interpreters.channel_send(10, b'spam') + + def test_recv_not_found(self): + with self.assertRaises(interpreters.ChannelNotFoundError): + interpreters.channel_recv(10) + + def test_recv_empty(self): + cid = interpreters.channel_create() + with self.assertRaises(interpreters.ChannelEmptyError): + interpreters.channel_recv(cid) + + def test_run_string_arg(self): + cid = interpreters.channel_create() + interp = interpreters.create() + + out = _run_output(interp, dedent(""" + import _xxsubinterpreters as _interpreters + print(cid.end) + _interpreters.channel_send(cid, b'spam') + """), + dict(cid=cid.send)) + obj = interpreters.channel_recv(cid) + + self.assertEqual(obj, b'spam') + self.assertEqual(out.strip(), 'send') + + +if __name__ == '__main__': + unittest.main() diff --git a/Misc/NEWS.d/next/Tests/2018-01-26-21-29-09.bpo-32604.7iazNx.rst b/Misc/NEWS.d/next/Tests/2018-01-26-21-29-09.bpo-32604.7iazNx.rst new file mode 100644 index 00000000000..f5472f9fe23 --- /dev/null +++ b/Misc/NEWS.d/next/Tests/2018-01-26-21-29-09.bpo-32604.7iazNx.rst @@ -0,0 +1,4 @@ +Add a new "_xxsubinterpreters" extension module that exposes the existing +subinterpreter C-API and a new cross-interpreter data sharing mechanism. The +module is primarily intended for more thorough testing of the existing +subinterpreter support. diff --git a/Modules/_xxsubinterpretersmodule.c b/Modules/_xxsubinterpretersmodule.c new file mode 100644 index 00000000000..ed79a13d4a4 --- /dev/null +++ b/Modules/_xxsubinterpretersmodule.c @@ -0,0 +1,2061 @@ + +/* interpreters module */ +/* low-level access to interpreter primitives */ + +#include "Python.h" +#include "frameobject.h" +#include "internal/pystate.h" + + +static PyInterpreterState * +_get_current(void) +{ + PyThreadState *tstate = PyThreadState_Get(); + // PyThreadState_Get() aborts if lookup fails, so we don't need + // to check the result for NULL. + return tstate->interp; +} + +static int64_t +_coerce_id(PyObject *id) +{ + id = PyNumber_Long(id); + if (id == NULL) { + if (PyErr_ExceptionMatches(PyExc_TypeError)) { + PyErr_SetString(PyExc_TypeError, + "'id' must be a non-negative int"); + } + else { + PyErr_SetString(PyExc_ValueError, + "'id' must be a non-negative int"); + } + return -1; + } + long long cid = PyLong_AsLongLong(id); + if (cid == -1 && PyErr_Occurred() != NULL) { + PyErr_SetString(PyExc_ValueError, + "'id' must be a non-negative int"); + return -1; + } + if (cid < 0) { + PyErr_SetString(PyExc_ValueError, + "'id' must be a non-negative int"); + return -1; + } + if (cid > INT64_MAX) { + PyErr_SetString(PyExc_ValueError, + "'id' too large (must be 64-bit int)"); + return -1; + } + return cid; +} + +/* data-sharing-specific code ***********************************************/ + +typedef struct _shareditem { + Py_UNICODE *name; + Py_ssize_t namelen; + _PyCrossInterpreterData data; +} _shareditem; + +void +_sharedns_clear(_shareditem *shared) +{ + for (_shareditem *item=shared; item->name != NULL; item += 1) { + _PyCrossInterpreterData_Release(&item->data); + } +} + +static _shareditem * +_get_shared_ns(PyObject *shareable, Py_ssize_t *lenp) +{ + if (shareable == NULL || shareable == Py_None) { + *lenp = 0; + return NULL; + } + Py_ssize_t len = PyDict_Size(shareable); + *lenp = len; + if (len == 0) { + return NULL; + } + + _shareditem *shared = PyMem_NEW(_shareditem, len+1); + if (shared == NULL) { + return NULL; + } + for (Py_ssize_t i=0; i < len; i++) { + *(shared + i) = (_shareditem){0}; + } + Py_ssize_t pos = 0; + for (Py_ssize_t i=0; i < len; i++) { + PyObject *key, *value; + if (PyDict_Next(shareable, &pos, &key, &value) == 0) { + break; + } + _shareditem *item = shared + i; + + if (_PyObject_GetCrossInterpreterData(value, &item->data) != 0) { + break; + } + item->name = PyUnicode_AsUnicodeAndSize(key, &item->namelen); + if (item->name == NULL) { + _PyCrossInterpreterData_Release(&item->data); + break; + } + (item + 1)->name = NULL; // Mark the next one as the last. + } + if (PyErr_Occurred()) { + _sharedns_clear(shared); + PyMem_Free(shared); + return NULL; + } + return shared; +} + +static int +_shareditem_apply(_shareditem *item, PyObject *ns) +{ + PyObject *name = PyUnicode_FromUnicode(item->name, item->namelen); + if (name == NULL) { + return 1; + } + PyObject *value = _PyCrossInterpreterData_NewObject(&item->data); + if (value == NULL) { + Py_DECREF(name); + return 1; + } + int res = PyDict_SetItem(ns, name, value); + Py_DECREF(name); + Py_DECREF(value); + return res; +} + +// Ultimately we'd like to preserve enough information about the +// exception and traceback that we could re-constitute (or at least +// simulate, a la traceback.TracebackException), and even chain, a copy +// of the exception in the calling interpreter. + +typedef struct _sharedexception { + char *msg; +} _sharedexception; + +static _sharedexception * +_get_shared_exception(void) +{ + _sharedexception *err = PyMem_NEW(_sharedexception, 1); + if (err == NULL) { + return NULL; + } + PyObject *exc; + PyObject *value; + PyObject *tb; + PyErr_Fetch(&exc, &value, &tb); + PyObject *msg; + if (value == NULL) { + msg = PyUnicode_FromFormat("%S", exc); + } + else { + msg = PyUnicode_FromFormat("%S: %S", exc, value); + } + if (msg == NULL) { + err->msg = "unable to format exception"; + return err; + } + err->msg = (char *)PyUnicode_AsUTF8(msg); + if (err->msg == NULL) { + err->msg = "unable to encode exception"; + } + return err; +} + +static PyObject * RunFailedError; + +static int +interp_exceptions_init(PyObject *ns) +{ + // XXX Move the exceptions into per-module memory? + + // An uncaught exception came out of interp_run_string(). + RunFailedError = PyErr_NewException("_xxsubinterpreters.RunFailedError", + PyExc_RuntimeError, NULL); + if (RunFailedError == NULL) { + return -1; + } + if (PyDict_SetItemString(ns, "RunFailedError", RunFailedError) != 0) { + return -1; + } + + return 0; +} + +static void +_apply_shared_exception(_sharedexception *exc) +{ + PyErr_SetString(RunFailedError, exc->msg); +} + +/* channel-specific code */ + +static PyObject *ChannelError; +static PyObject *ChannelNotFoundError; +static PyObject *ChannelClosedError; +static PyObject *ChannelEmptyError; + +static int +channel_exceptions_init(PyObject *ns) +{ + // XXX Move the exceptions into per-module memory? + + // A channel-related operation failed. + ChannelError = PyErr_NewException("_xxsubinterpreters.ChannelError", + PyExc_RuntimeError, NULL); + if (ChannelError == NULL) { + return -1; + } + if (PyDict_SetItemString(ns, "ChannelError", ChannelError) != 0) { + return -1; + } + + // An operation tried to use a channel that doesn't exist. + ChannelNotFoundError = PyErr_NewException( + "_xxsubinterpreters.ChannelNotFoundError", ChannelError, NULL); + if (ChannelNotFoundError == NULL) { + return -1; + } + if (PyDict_SetItemString(ns, "ChannelNotFoundError", ChannelNotFoundError) != 0) { + return -1; + } + + // An operation tried to use a closed channel. + ChannelClosedError = PyErr_NewException( + "_xxsubinterpreters.ChannelClosedError", ChannelError, NULL); + if (ChannelClosedError == NULL) { + return -1; + } + if (PyDict_SetItemString(ns, "ChannelClosedError", ChannelClosedError) != 0) { + return -1; + } + + // An operation tried to pop from an empty channel. + ChannelEmptyError = PyErr_NewException( + "_xxsubinterpreters.ChannelEmptyError", ChannelError, NULL); + if (ChannelEmptyError == NULL) { + return -1; + } + if (PyDict_SetItemString(ns, "ChannelEmptyError", ChannelEmptyError) != 0) { + return -1; + } + + return 0; +} + +struct _channelend; + +typedef struct _channelend { + struct _channelend *next; + int64_t interp; + int open; +} _channelend; + +static _channelend * +_channelend_new(int64_t interp) +{ + _channelend *end = PyMem_NEW(_channelend, 1); + if (end == NULL) { + return NULL; + } + + end->next = NULL; + end->interp = interp; + + end->open = 1; + + return end; +} + +static void +_channelend_free_all(_channelend *end) { + while (end != NULL) { + _channelend *last = end; + end = end->next; + PyMem_Free(last); + } +} + +static _channelend * +_channelend_find(_channelend *first, int64_t interp, _channelend **pprev) +{ + _channelend *prev = NULL; + _channelend *end = first; + while (end != NULL) { + if (end->interp == interp) { + break; + } + prev = end; + end = end->next; + } + if (pprev != NULL) { + *pprev = prev; + } + return end; +} + +struct _channelitem; + +typedef struct _channelitem { + _PyCrossInterpreterData *data; + struct _channelitem *next; +} _channelitem; + +struct _channel; + +typedef struct _channel { + PyThread_type_lock mutex; + + int open; + + int64_t count; + _channelitem *first; + _channelitem *last; + + // Note that the list entries are never removed for interpreter + // for which the channel is closed. This should be a problem in + // practice. Also, a channel isn't automatically closed when an + // interpreter is destroyed. + int64_t numsendopen; + int64_t numrecvopen; + _channelend *send; + _channelend *recv; +} _PyChannelState; + +static _PyChannelState * +_channel_new(void) +{ + _PyChannelState *chan = PyMem_NEW(_PyChannelState, 1); + if (chan == NULL) { + return NULL; + } + chan->mutex = PyThread_allocate_lock(); + if (chan->mutex == NULL) { + PyMem_Free(chan); + PyErr_SetString(ChannelError, + "can't initialize mutex for new channel"); + return NULL; + } + + chan->open = 1; + + chan->count = 0; + chan->first = NULL; + chan->last = NULL; + + chan->numsendopen = 0; + chan->numrecvopen = 0; + chan->send = NULL; + chan->recv = NULL; + + return chan; +} + +static _channelend * +_channel_add_end(_PyChannelState *chan, _channelend *prev, int64_t interp, + int send) +{ + _channelend *end = _channelend_new(interp); + if (end == NULL) { + return NULL; + } + + if (prev == NULL) { + if (send) { + chan->send = end; + } + else { + chan->recv = end; + } + } + else { + prev->next = end; + } + if (send) { + chan->numsendopen += 1; + } + else { + chan->numrecvopen += 1; + } + return end; +} + +static _channelend * +_channel_associate_end(_PyChannelState *chan, int64_t interp, int send) +{ + if (!chan->open) { + PyErr_SetString(ChannelClosedError, "channel closed"); + return NULL; + } + + _channelend *prev; + _channelend *end = _channelend_find(send ? chan->send : chan->recv, + interp, &prev); + if (end != NULL) { + if (!end->open) { + PyErr_SetString(ChannelClosedError, "channel already closed"); + return NULL; + } + // already associated + return end; + } + return _channel_add_end(chan, prev, interp, send); +} + +static void +_channel_close_channelend(_PyChannelState *chan, _channelend *end, int send) +{ + end->open = 0; + if (send) { + chan->numsendopen -= 1; + } + else { + chan->numrecvopen -= 1; + } +} + +static int +_channel_close_interpreter(_PyChannelState *chan, int64_t interp, int which) +{ + PyThread_acquire_lock(chan->mutex, WAIT_LOCK); + + int res = -1; + if (!chan->open) { + PyErr_SetString(ChannelClosedError, "channel already closed"); + goto done; + } + + _channelend *prev; + _channelend *end; + if (which >= 0) { // send/both + end = _channelend_find(chan->send, interp, &prev); + if (end == NULL) { + // never associated so add it + end = _channel_add_end(chan, prev, interp, 1); + if (end == NULL) { + goto done; + } + } + _channel_close_channelend(chan, end, 1); + } + if (which <= 0) { // recv/both + end = _channelend_find(chan->recv, interp, &prev); + if (end == NULL) { + // never associated so add it + end = _channel_add_end(chan, prev, interp, 0); + if (end == NULL) { + goto done; + } + } + _channel_close_channelend(chan, end, 0); + } + + if (chan->numsendopen == 0 && chan->numrecvopen == 0) { + if (chan->send != NULL || chan->recv != NULL) { + chan->open = 0; + } + } + + res = 0; +done: + PyThread_release_lock(chan->mutex); + return res; +} + +static int +_channel_close_all(_PyChannelState *chan) +{ + int res = -1; + PyThread_acquire_lock(chan->mutex, WAIT_LOCK); + + if (!chan->open) { + PyErr_SetString(ChannelClosedError, "channel already closed"); + goto done; + } + + chan->open = 0; + + // We *could* also just leave these in place, since we've marked + // the channel as closed already. + + // Ensure all the "send"-associated interpreters are closed. + _channelend *end; + for (end = chan->send; end != NULL; end = end->next) { + _channel_close_channelend(chan, end, 1); + } + + // Ensure all the "recv"-associated interpreters are closed. + for (end = chan->recv; end != NULL; end = end->next) { + _channel_close_channelend(chan, end, 0); + } + + res = 0; +done: + PyThread_release_lock(chan->mutex); + return res; +} + +static int +_channel_add(_PyChannelState *chan, int64_t interp, + _PyCrossInterpreterData *data) +{ + int res = -1; + + PyThread_acquire_lock(chan->mutex, WAIT_LOCK); + if (_channel_associate_end(chan, interp, 1) == NULL) { + goto done; + } + + _channelitem *item = PyMem_NEW(_channelitem, 1); + if (item == NULL) { + goto done; + } + item->data = data; + item->next = NULL; + + chan->count += 1; + if (chan->first == NULL) { + chan->first = item; + } + chan->last = item; + + res = 0; +done: + PyThread_release_lock(chan->mutex); + return res; +} + +static _PyCrossInterpreterData * +_channel_next(_PyChannelState *chan, int64_t interp) +{ + _PyCrossInterpreterData *data = NULL; + PyThread_acquire_lock(chan->mutex, WAIT_LOCK); + if (_channel_associate_end(chan, interp, 0) == NULL) { + goto done; + } + + _channelitem *item = chan->first; + if (item == NULL) { + goto done; + } + chan->first = item->next; + if (chan->last == item) { + chan->last = NULL; + } + chan->count -= 1; + + data = item->data; + PyMem_Free(item); + +done: + PyThread_release_lock(chan->mutex); + return data; +} + +static void +_channel_clear(_PyChannelState *chan) +{ + _channelitem *item = chan->first; + while (item != NULL) { + _PyCrossInterpreterData_Release(item->data); + PyMem_Free(item->data); + _channelitem *last = item; + item = item->next; + PyMem_Free(last); + } + chan->first = NULL; + chan->last = NULL; +} + +static void +_channel_free(_PyChannelState *chan) +{ + PyThread_acquire_lock(chan->mutex, WAIT_LOCK); + _channel_clear(chan); + _channelend_free_all(chan->send); + _channelend_free_all(chan->recv); + PyThread_release_lock(chan->mutex); + + PyThread_free_lock(chan->mutex); + PyMem_Free(chan); +} + +struct _channelref; + +typedef struct _channelref { + int64_t id; + _PyChannelState *chan; + struct _channelref *next; + Py_ssize_t objcount; +} _channelref; + +static _channelref * +_channelref_new(int64_t id, _PyChannelState *chan) +{ + _channelref *ref = PyMem_NEW(_channelref, 1); + if (ref == NULL) { + return NULL; + } + ref->id = id; + ref->chan = chan; + ref->next = NULL; + ref->objcount = 0; + return ref; +} + +static _channelref * +_channelref_find(_channelref *first, int64_t id, _channelref **pprev) +{ + _channelref *prev = NULL; + _channelref *ref = first; + while (ref != NULL) { + if (ref->id == id) { + break; + } + prev = ref; + ref = ref->next; + } + if (pprev != NULL) { + *pprev = prev; + } + return ref; +} + +typedef struct _channels { + PyThread_type_lock mutex; + _channelref *head; + int64_t numopen; + int64_t next_id; +} _channels; + +static int +_channels_init(_channels *channels) +{ + if (channels->mutex == NULL) { + channels->mutex = PyThread_allocate_lock(); + if (channels->mutex == NULL) { + PyMem_Free(channels); + PyErr_SetString(ChannelError, + "can't initialize mutex for channel management"); + return -1; + } + } + channels->head = NULL; + channels->numopen = 0; + channels->next_id = 0; + return 0; +} + +static int64_t +_channels_next_id(_channels *channels) // needs lock +{ + int64_t id = channels->next_id; + if (id < 0) { + /* overflow */ + PyErr_SetString(ChannelError, + "failed to get a channel ID"); + return -1; + } + channels->next_id += 1; + return id; +} + +static _PyChannelState * +_channels_lookup(_channels *channels, int64_t id, PyThread_type_lock *pmutex) +{ + _PyChannelState *chan = NULL; + PyThread_acquire_lock(channels->mutex, WAIT_LOCK); + if (pmutex != NULL) { + *pmutex = NULL; + } + + _channelref *ref = _channelref_find(channels->head, id, NULL); + if (ref == NULL) { + PyErr_Format(ChannelNotFoundError, "channel %d not found", id); + goto done; + } + if (ref->chan == NULL || !ref->chan->open) { + PyErr_Format(ChannelClosedError, "channel %d closed", id); + goto done; + } + + if (pmutex != NULL) { + // The mutex will be closed by the caller. + *pmutex = channels->mutex; + } + + chan = ref->chan; +done: + if (pmutex == NULL || *pmutex == NULL) { + PyThread_release_lock(channels->mutex); + } + return chan; +} + +static int64_t +_channels_add(_channels *channels, _PyChannelState *chan) +{ + int64_t cid = -1; + PyThread_acquire_lock(channels->mutex, WAIT_LOCK); + + // Create a new ref. + int64_t id = _channels_next_id(channels); + if (id < 0) { + goto done; + } + _channelref *ref = _channelref_new(id, chan); + if (ref == NULL) { + goto done; + } + + // Add it to the list. + // We assume that the channel is a new one (not already in the list). + ref->next = channels->head; + channels->head = ref; + channels->numopen += 1; + + cid = id; +done: + PyThread_release_lock(channels->mutex); + return cid; +} + +static int +_channels_close(_channels *channels, int64_t cid, _PyChannelState **pchan) +{ + int res = -1; + PyThread_acquire_lock(channels->mutex, WAIT_LOCK); + if (pchan != NULL) { + *pchan = NULL; + } + + _channelref *ref = _channelref_find(channels->head, cid, NULL); + if (ref == NULL) { + PyErr_Format(ChannelNotFoundError, "channel %d not found", cid); + goto done; + } + + if (ref->chan == NULL) { + PyErr_Format(ChannelClosedError, "channel %d closed", cid); + goto done; + } + else { + if (_channel_close_all(ref->chan) != 0) { + goto done; + } + if (pchan != NULL) { + *pchan = ref->chan; + } + ref->chan = NULL; + } + + res = 0; +done: + PyThread_release_lock(channels->mutex); + return res; +} + +static void +_channels_remove_ref(_channels *channels, _channelref *ref, _channelref *prev, + _PyChannelState **pchan) +{ + if (ref == channels->head) { + channels->head = ref->next; + } + else { + prev->next = ref->next; + } + channels->numopen -= 1; + + if (pchan != NULL) { + *pchan = ref->chan; + } + PyMem_Free(ref); +} + +static int +_channels_remove(_channels *channels, int64_t id, _PyChannelState **pchan) +{ + int res = -1; + PyThread_acquire_lock(channels->mutex, WAIT_LOCK); + + if (pchan != NULL) { + *pchan = NULL; + } + + _channelref *prev = NULL; + _channelref *ref = _channelref_find(channels->head, id, &prev); + if (ref == NULL) { + PyErr_Format(ChannelNotFoundError, "channel %d not found", id); + goto done; + } + + _channels_remove_ref(channels, ref, prev, pchan); + + res = 0; +done: + PyThread_release_lock(channels->mutex); + return res; +} + +static int +_channels_add_id_object(_channels *channels, int64_t id) +{ + int res = -1; + PyThread_acquire_lock(channels->mutex, WAIT_LOCK); + + _channelref *ref = _channelref_find(channels->head, id, NULL); + if (ref == NULL) { + PyErr_Format(ChannelNotFoundError, "channel %d not found", id); + goto done; + } + ref->objcount += 1; + + res = 0; +done: + PyThread_release_lock(channels->mutex); + return res; +} + +static void +_channels_drop_id_object(_channels *channels, int64_t id) +{ + PyThread_acquire_lock(channels->mutex, WAIT_LOCK); + + _channelref *prev = NULL; + _channelref *ref = _channelref_find(channels->head, id, &prev); + if (ref == NULL) { + // Already destroyed. + goto done; + } + ref->objcount -= 1; + + // Destroy if no longer used. + if (ref->objcount == 0) { + _PyChannelState *chan = NULL; + _channels_remove_ref(channels, ref, prev, &chan); + if (chan != NULL) { + _channel_free(chan); + } + } + +done: + PyThread_release_lock(channels->mutex); +} + +int64_t * +_channels_list_all(_channels *channels, int64_t *count) +{ + int64_t *cids = NULL; + PyThread_acquire_lock(channels->mutex, WAIT_LOCK); + int64_t numopen = channels->numopen; + if (numopen >= PY_SSIZE_T_MAX) { + PyErr_SetString(PyExc_RuntimeError, "too many channels open"); + goto done; + } + int64_t *ids = PyMem_NEW(int64_t, (Py_ssize_t)(channels->numopen)); + if (ids == NULL) { + goto done; + } + _channelref *ref = channels->head; + for (int64_t i=0; ref != NULL; ref = ref->next, i++) { + ids[i] = ref->id; + } + *count = channels->numopen; + + cids = ids; +done: + PyThread_release_lock(channels->mutex); + return cids; +} + +/* "high"-level channel-related functions */ + +static int64_t +_channel_create(_channels *channels) +{ + _PyChannelState *chan = _channel_new(); + if (chan == NULL) { + return -1; + } + int64_t id = _channels_add(channels, chan); + if (id < 0) { + _channel_free(chan); + return -1; + } + return id; +} + +static int +_channel_destroy(_channels *channels, int64_t id) +{ + _PyChannelState *chan = NULL; + if (_channels_remove(channels, id, &chan) != 0) { + return -1; + } + if (chan != NULL) { + _channel_free(chan); + } + return 0; +} + +static int +_channel_send(_channels *channels, int64_t id, PyObject *obj) +{ + PyInterpreterState *interp = _get_current(); + if (interp == NULL) { + return -1; + } + + // Look up the channel. + PyThread_type_lock mutex = NULL; + _PyChannelState *chan = _channels_lookup(channels, id, &mutex); + if (chan == NULL) { + return -1; + } + // Past this point we are responsible for releasing the mutex. + + // Convert the object to cross-interpreter data. + _PyCrossInterpreterData *data = PyMem_NEW(_PyCrossInterpreterData, 1); + if (data == NULL) { + PyThread_release_lock(mutex); + return -1; + } + if (_PyObject_GetCrossInterpreterData(obj, data) != 0) { + PyThread_release_lock(mutex); + return -1; + } + + // Add the data to the channel. + int res = _channel_add(chan, interp->id, data); + PyThread_release_lock(mutex); + if (res != 0) { + _PyCrossInterpreterData_Release(data); + PyMem_Free(data); + return -1; + } + + return 0; +} + +static PyObject * +_channel_recv(_channels *channels, int64_t id) +{ + PyInterpreterState *interp = _get_current(); + if (interp == NULL) { + return NULL; + } + + // Look up the channel. + PyThread_type_lock mutex = NULL; + _PyChannelState *chan = _channels_lookup(channels, id, &mutex); + if (chan == NULL) { + return NULL; + } + // Past this point we are responsible for releasing the mutex. + + // Pop off the next item from the channel. + _PyCrossInterpreterData *data = _channel_next(chan, interp->id); + PyThread_release_lock(mutex); + if (data == NULL) { + PyErr_Format(ChannelEmptyError, "channel %d is empty", id); + return NULL; + } + + // Convert the data back to an object. + PyObject *obj = _PyCrossInterpreterData_NewObject(data); + if (obj == NULL) { + return NULL; + } + _PyCrossInterpreterData_Release(data); + + return obj; +} + +static int +_channel_drop(_channels *channels, int64_t id, int send, int recv) +{ + PyInterpreterState *interp = _get_current(); + if (interp == NULL) { + return -1; + } + + // Look up the channel. + PyThread_type_lock mutex = NULL; + _PyChannelState *chan = _channels_lookup(channels, id, &mutex); + if (chan == NULL) { + return -1; + } + // Past this point we are responsible for releasing the mutex. + + // Close one or both of the two ends. + int res =_channel_close_interpreter(chan, interp->id, send-recv); + PyThread_release_lock(mutex); + return res; +} + +static int +_channel_close(_channels *channels, int64_t id) +{ + return _channels_close(channels, id, NULL); +} + +/* ChannelID class */ + +#define CHANNEL_SEND 1 +#define CHANNEL_RECV -1 + +static PyTypeObject ChannelIDtype; + +typedef struct channelid { + PyObject_HEAD + int64_t id; + int end; + _channels *channels; +} channelid; + +static channelid * +newchannelid(PyTypeObject *cls, int64_t cid, int end, _channels *channels, + int force) +{ + channelid *self = PyObject_New(channelid, cls); + if (self == NULL) { + return NULL; + } + self->id = cid; + self->end = end; + self->channels = channels; + + if (_channels_add_id_object(channels, cid) != 0) { + if (force && PyErr_ExceptionMatches(ChannelNotFoundError)) { + PyErr_Clear(); + } + else { + Py_DECREF((PyObject *)self); + return NULL; + } + } + + return self; +} + +static _channels * _global_channels(void); + +static PyObject * +channelid_new(PyTypeObject *cls, PyObject *args, PyObject *kwds) +{ + static char *kwlist[] = {"id", "send", "recv", "force", NULL}; + PyObject *id; + int send = -1; + int recv = -1; + int force = 0; + if (!PyArg_ParseTupleAndKeywords(args, kwds, + "O|$ppp:ChannelID.__init__", kwlist, + &id, &send, &recv, &force)) + return NULL; + + // Coerce and check the ID. + int64_t cid; + if (PyObject_TypeCheck(id, &ChannelIDtype)) { + cid = ((channelid *)id)->id; + } + else { + cid = _coerce_id(id); + if (cid < 0) { + return NULL; + } + } + + // Handle "send" and "recv". + if (send == 0 && recv == 0) { + PyErr_SetString(PyExc_ValueError, + "'send' and 'recv' cannot both be False"); + return NULL; + } + int end = 0; + if (send == 1) { + if (recv == 0 || recv == -1) { + end = CHANNEL_SEND; + } + } + else if (recv == 1) { + end = CHANNEL_RECV; + } + + return (PyObject *)newchannelid(cls, cid, end, _global_channels(), force); +} + +static void +channelid_dealloc(PyObject *v) +{ + int64_t cid = ((channelid *)v)->id; + _channels *channels = ((channelid *)v)->channels; + Py_TYPE(v)->tp_free(v); + + _channels_drop_id_object(channels, cid); +} + +static PyObject * +channelid_repr(PyObject *self) +{ + PyTypeObject *type = Py_TYPE(self); + const char *name = _PyType_Name(type); + + channelid *cid = (channelid *)self; + const char *fmt; + if (cid->end == CHANNEL_SEND) { + fmt = "%s(%d, send=True)"; + } + else if (cid->end == CHANNEL_RECV) { + fmt = "%s(%d, recv=True)"; + } + else { + fmt = "%s(%d)"; + } + return PyUnicode_FromFormat(fmt, name, cid->id); +} + +PyObject * +channelid_int(PyObject *self) +{ + channelid *cid = (channelid *)self; + return PyLong_FromLongLong(cid->id); +} + +static PyNumberMethods channelid_as_number = { + 0, /* nb_add */ + 0, /* nb_subtract */ + 0, /* nb_multiply */ + 0, /* nb_remainder */ + 0, /* nb_divmod */ + 0, /* nb_power */ + 0, /* nb_negative */ + 0, /* nb_positive */ + 0, /* nb_absolute */ + 0, /* nb_bool */ + 0, /* nb_invert */ + 0, /* nb_lshift */ + 0, /* nb_rshift */ + 0, /* nb_and */ + 0, /* nb_xor */ + 0, /* nb_or */ + (unaryfunc)channelid_int, /* nb_int */ + 0, /* nb_reserved */ + 0, /* nb_float */ + + 0, /* nb_inplace_add */ + 0, /* nb_inplace_subtract */ + 0, /* nb_inplace_multiply */ + 0, /* nb_inplace_remainder */ + 0, /* nb_inplace_power */ + 0, /* nb_inplace_lshift */ + 0, /* nb_inplace_rshift */ + 0, /* nb_inplace_and */ + 0, /* nb_inplace_xor */ + 0, /* nb_inplace_or */ + + 0, /* nb_floor_divide */ + 0, /* nb_true_divide */ + 0, /* nb_inplace_floor_divide */ + 0, /* nb_inplace_true_divide */ + + (unaryfunc)channelid_int, /* nb_index */ +}; + +static Py_hash_t +channelid_hash(PyObject *self) +{ + channelid *cid = (channelid *)self; + PyObject *id = PyLong_FromLongLong(cid->id); + if (id == NULL) { + return -1; + } + return PyObject_Hash(id); +} + +static PyObject * +channelid_richcompare(PyObject *self, PyObject *other, int op) +{ + if (op != Py_EQ && op != Py_NE) { + Py_RETURN_NOTIMPLEMENTED; + } + + if (!PyObject_TypeCheck(self, &ChannelIDtype)) { + Py_RETURN_NOTIMPLEMENTED; + } + + channelid *cid = (channelid *)self; + int equal; + if (PyObject_TypeCheck(other, &ChannelIDtype)) { + channelid *othercid = (channelid *)other; + if (cid->end != othercid->end) { + equal = 0; + } + else { + equal = (cid->id == othercid->id); + } + } + else { + other = PyNumber_Long(other); + if (other == NULL) { + PyErr_Clear(); + Py_RETURN_NOTIMPLEMENTED; + } + int64_t othercid = PyLong_AsLongLong(other); + // XXX decref other here? + if (othercid == -1 && PyErr_Occurred() != NULL) { + return NULL; + } + if (othercid < 0 || othercid > INT64_MAX) { + equal = 0; + } + else { + equal = (cid->id == othercid); + } + } + + if ((op == Py_EQ && equal) || (op == Py_NE && !equal)) { + Py_RETURN_TRUE; + } + Py_RETURN_FALSE; +} + +struct _channelid_xid { + int64_t id; + int end; +}; + +static PyObject * +_channelid_from_xid(_PyCrossInterpreterData *data) +{ + struct _channelid_xid *xid = (struct _channelid_xid *)data->data; + return (PyObject *)newchannelid(&ChannelIDtype, xid->id, xid->end, + _global_channels(), 0); +} + +static int +_channelid_shared(PyObject *obj, _PyCrossInterpreterData *data) +{ + struct _channelid_xid *xid = PyMem_NEW(struct _channelid_xid, 1); + if (xid == NULL) { + return -1; + } + xid->id = ((channelid *)obj)->id; + xid->end = ((channelid *)obj)->end; + + data->data = xid; + data->obj = obj; + data->new_object = _channelid_from_xid; + data->free = PyMem_Free; + return 0; +} + +static PyObject * +channelid_end(PyObject *self, void *end) +{ + int force = 1; + channelid *cid = (channelid *)self; + if (end != NULL) { + return (PyObject *)newchannelid(Py_TYPE(self), cid->id, *(int *)end, + cid->channels, force); + } + + if (cid->end == CHANNEL_SEND) { + return PyUnicode_InternFromString("send"); + } + if (cid->end == CHANNEL_RECV) { + return PyUnicode_InternFromString("recv"); + } + return PyUnicode_InternFromString("both"); +} + +static int _channelid_end_send = CHANNEL_SEND; +static int _channelid_end_recv = CHANNEL_RECV; + +static PyGetSetDef channelid_getsets[] = { + {"end", (getter)channelid_end, NULL, + PyDoc_STR("'send', 'recv', or 'both'")}, + {"send", (getter)channelid_end, NULL, + PyDoc_STR("the 'send' end of the channel"), &_channelid_end_send}, + {"recv", (getter)channelid_end, NULL, + PyDoc_STR("the 'recv' end of the channel"), &_channelid_end_recv}, + {NULL} +}; + +PyDoc_STRVAR(channelid_doc, +"A channel ID identifies a channel and may be used as an int."); + +static PyTypeObject ChannelIDtype = { + PyVarObject_HEAD_INIT(&PyType_Type, 0) + "_xxsubinterpreters.ChannelID", /* tp_name */ + sizeof(channelid), /* tp_size */ + 0, /* tp_itemsize */ + (destructor)channelid_dealloc, /* tp_dealloc */ + 0, /* tp_print */ + 0, /* tp_getattr */ + 0, /* tp_setattr */ + 0, /* tp_as_async */ + (reprfunc)channelid_repr, /* tp_repr */ + &channelid_as_number, /* tp_as_number */ + 0, /* tp_as_sequence */ + 0, /* tp_as_mapping */ + channelid_hash, /* tp_hash */ + 0, /* tp_call */ + 0, /* tp_str */ + 0, /* tp_getattro */ + 0, /* tp_setattro */ + 0, /* tp_as_buffer */ + Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | + Py_TPFLAGS_LONG_SUBCLASS, /* tp_flags */ + channelid_doc, /* tp_doc */ + 0, /* tp_traverse */ + 0, /* tp_clear */ + channelid_richcompare, /* tp_richcompare */ + 0, /* tp_weaklistoffset */ + 0, /* tp_iter */ + 0, /* tp_iternext */ + 0, /* tp_methods */ + 0, /* tp_members */ + channelid_getsets, /* tp_getset */ + 0, /* tp_base */ + 0, /* tp_dict */ + 0, /* tp_descr_get */ + 0, /* tp_descr_set */ + 0, /* tp_dictoffset */ + 0, /* tp_init */ + 0, /* tp_alloc */ + // Note that we do not set tp_new to channelid_new. Instead we + // set it to NULL, meaning it cannot be instantiated from Python + // code. We do this because there is a strong relationship between + // channel IDs and the channel lifecycle, so this limitation avoids + // related complications. + NULL, /* tp_new */ +}; + +/* interpreter-specific functions *******************************************/ + +static PyInterpreterState * +_look_up(PyObject *requested_id) +{ + long long id = PyLong_AsLongLong(requested_id); + if (id == -1 && PyErr_Occurred() != NULL) { + return NULL; + } + assert(id <= INT64_MAX); + return _PyInterpreterState_LookUpID(id); +} + +static PyObject * +_get_id(PyInterpreterState *interp) +{ + PY_INT64_T id = PyInterpreterState_GetID(interp); + if (id < 0) { + return NULL; + } + return PyLong_FromLongLong(id); +} + +static int +_is_running(PyInterpreterState *interp) +{ + PyThreadState *tstate = PyInterpreterState_ThreadHead(interp); + if (PyThreadState_Next(tstate) != NULL) { + PyErr_SetString(PyExc_RuntimeError, + "interpreter has more than one thread"); + return -1; + } + PyFrameObject *frame = tstate->frame; + if (frame == NULL) { + if (PyErr_Occurred() != NULL) { + return -1; + } + return 0; + } + return (int)(frame->f_executing); +} + +static int +_ensure_not_running(PyInterpreterState *interp) +{ + int is_running = _is_running(interp); + if (is_running < 0) { + return -1; + } + if (is_running) { + PyErr_Format(PyExc_RuntimeError, "interpreter already running"); + return -1; + } + return 0; +} + +static int +_run_script(PyInterpreterState *interp, const char *codestr, + _shareditem *shared, Py_ssize_t num_shared, + _sharedexception **exc) +{ + assert(num_shared >= 0); + PyObject *main_mod = PyMapping_GetItemString(interp->modules, "__main__"); + if (main_mod == NULL) { + goto error; + } + PyObject *ns = PyModule_GetDict(main_mod); // borrowed + Py_DECREF(main_mod); + if (ns == NULL) { + goto error; + } + Py_INCREF(ns); + + // Apply the cross-interpreter data. + if (shared != NULL) { + for (Py_ssize_t i=0; i < num_shared; i++) { + _shareditem *item = &shared[i]; + if (_shareditem_apply(item, ns) != 0) { + Py_DECREF(ns); + goto error; + } + } + } + + // Run the string (see PyRun_SimpleStringFlags). + PyObject *result = PyRun_StringFlags(codestr, Py_file_input, ns, ns, NULL); + Py_DECREF(ns); + if (result == NULL) { + goto error; + } + else { + Py_DECREF(result); // We throw away the result. + } + + return 0; + +error: + *exc = _get_shared_exception(); + PyErr_Clear(); + return -1; +} + +static int +_run_script_in_interpreter(PyInterpreterState *interp, const char *codestr, + PyObject *shareables) +{ + if (_ensure_not_running(interp) < 0) { + return -1; + } + + Py_ssize_t num_shared = -1; + _shareditem *shared = _get_shared_ns(shareables, &num_shared); + if (shared == NULL && PyErr_Occurred()) { + return -1; + } + + // Switch to interpreter. + PyThreadState *tstate = PyInterpreterState_ThreadHead(interp); + PyThreadState *save_tstate = PyThreadState_Swap(tstate); + + // Run the script. + _sharedexception *exc = NULL; + int result = _run_script(interp, codestr, shared, num_shared, &exc); + + // Switch back. + if (save_tstate != NULL) { + PyThreadState_Swap(save_tstate); + } + + // Propagate any exception out to the caller. + if (exc != NULL) { + _apply_shared_exception(exc); + PyMem_Free(exc); + } + else if (result != 0) { + // We were unable to allocate a shared exception. + PyErr_NoMemory(); + } + + if (shared != NULL) { + _sharedns_clear(shared); + PyMem_Free(shared); + } + + return result; +} + + +/* module level code ********************************************************/ + +/* globals is the process-global state for the module. It holds all + the data that we need to share between interpreters, so it cannot + hold PyObject values. */ +static struct globals { + _channels channels; +} _globals = {{0}}; + +static int +_init_globals(void) +{ + if (_channels_init(&_globals.channels) != 0) { + return -1; + } + return 0; +} + +static _channels * +_global_channels(void) { + return &_globals.channels; +} + +static PyObject * +interp_create(PyObject *self, PyObject *args) +{ + if (!PyArg_UnpackTuple(args, "create", 0, 0)) { + return NULL; + } + + // Create and initialize the new interpreter. + PyThreadState *tstate, *save_tstate; + save_tstate = PyThreadState_Swap(NULL); + tstate = Py_NewInterpreter(); + PyThreadState_Swap(save_tstate); + if (tstate == NULL) { + /* Since no new thread state was created, there is no exception to + propagate; raise a fresh one after swapping in the old thread + state. */ + PyErr_SetString(PyExc_RuntimeError, "interpreter creation failed"); + return NULL; + } + return _get_id(tstate->interp); +} + +PyDoc_STRVAR(create_doc, +"create() -> ID\n\ +\n\ +Create a new interpreter and return a unique generated ID."); + + +static PyObject * +interp_destroy(PyObject *self, PyObject *args) +{ + PyObject *id; + if (!PyArg_UnpackTuple(args, "destroy", 1, 1, &id)) { + return NULL; + } + if (!PyLong_Check(id)) { + PyErr_SetString(PyExc_TypeError, "ID must be an int"); + return NULL; + } + + // Look up the interpreter. + PyInterpreterState *interp = _look_up(id); + if (interp == NULL) { + return NULL; + } + + // Ensure we don't try to destroy the current interpreter. + PyInterpreterState *current = _get_current(); + if (current == NULL) { + return NULL; + } + if (interp == current) { + PyErr_SetString(PyExc_RuntimeError, + "cannot destroy the current interpreter"); + return NULL; + } + + // Ensure the interpreter isn't running. + /* XXX We *could* support destroying a running interpreter but + aren't going to worry about it for now. */ + if (_ensure_not_running(interp) < 0) { + return NULL; + } + + // Destroy the interpreter. + //PyInterpreterState_Delete(interp); + PyThreadState *tstate, *save_tstate; + tstate = PyInterpreterState_ThreadHead(interp); + save_tstate = PyThreadState_Swap(tstate); + Py_EndInterpreter(tstate); + PyThreadState_Swap(save_tstate); + + Py_RETURN_NONE; +} + +PyDoc_STRVAR(destroy_doc, +"destroy(ID)\n\ +\n\ +Destroy the identified interpreter.\n\ +\n\ +Attempting to destroy the current interpreter results in a RuntimeError.\n\ +So does an unrecognized ID."); + + +static PyObject * +interp_list_all(PyObject *self) +{ + PyObject *ids, *id; + PyInterpreterState *interp; + + ids = PyList_New(0); + if (ids == NULL) { + return NULL; + } + + interp = PyInterpreterState_Head(); + while (interp != NULL) { + id = _get_id(interp); + if (id == NULL) { + Py_DECREF(ids); + return NULL; + } + // insert at front of list + if (PyList_Insert(ids, 0, id) < 0) { + Py_DECREF(ids); + return NULL; + } + + interp = PyInterpreterState_Next(interp); + } + + return ids; +} + +PyDoc_STRVAR(list_all_doc, +"list_all() -> [ID]\n\ +\n\ +Return a list containing the ID of every existing interpreter."); + + +static PyObject * +interp_get_current(PyObject *self) +{ + PyInterpreterState *interp =_get_current(); + if (interp == NULL) { + return NULL; + } + return _get_id(interp); +} + +PyDoc_STRVAR(get_current_doc, +"get_current() -> ID\n\ +\n\ +Return the ID of current interpreter."); + + +static PyObject * +interp_get_main(PyObject *self) +{ + // Currently, 0 is always the main interpreter. + return PyLong_FromLongLong(0); +} + +PyDoc_STRVAR(get_main_doc, +"get_main() -> ID\n\ +\n\ +Return the ID of main interpreter."); + + +static PyObject * +interp_run_string(PyObject *self, PyObject *args) +{ + PyObject *id, *code; + PyObject *shared = NULL; + if (!PyArg_UnpackTuple(args, "run_string", 2, 3, &id, &code, &shared)) { + return NULL; + } + if (!PyLong_Check(id)) { + PyErr_SetString(PyExc_TypeError, "first arg (ID) must be an int"); + return NULL; + } + if (!PyUnicode_Check(code)) { + PyErr_SetString(PyExc_TypeError, + "second arg (code) must be a string"); + return NULL; + } + + // Look up the interpreter. + PyInterpreterState *interp = _look_up(id); + if (interp == NULL) { + return NULL; + } + + // Extract code. + Py_ssize_t size; + const char *codestr = PyUnicode_AsUTF8AndSize(code, &size); + if (codestr == NULL) { + return NULL; + } + if (strlen(codestr) != (size_t)size) { + PyErr_SetString(PyExc_ValueError, + "source code string cannot contain null bytes"); + return NULL; + } + + // Run the code in the interpreter. + if (_run_script_in_interpreter(interp, codestr, shared) != 0) { + return NULL; + } + Py_RETURN_NONE; +} + +PyDoc_STRVAR(run_string_doc, +"run_string(ID, sourcetext)\n\ +\n\ +Execute the provided string in the identified interpreter.\n\ +\n\ +See PyRun_SimpleStrings."); + + +static PyObject * +object_is_shareable(PyObject *self, PyObject *args) +{ + PyObject *obj; + if (!PyArg_UnpackTuple(args, "is_shareable", 1, 1, &obj)) { + return NULL; + } + if (_PyObject_CheckCrossInterpreterData(obj) == 0) { + Py_RETURN_TRUE; + } + PyErr_Clear(); + Py_RETURN_FALSE; +} + +PyDoc_STRVAR(is_shareable_doc, +"is_shareable(obj) -> bool\n\ +\n\ +Return True if the object's data may be shared between interpreters and\n\ +False otherwise."); + + +static PyObject * +interp_is_running(PyObject *self, PyObject *args) +{ + PyObject *id; + if (!PyArg_UnpackTuple(args, "is_running", 1, 1, &id)) { + return NULL; + } + if (!PyLong_Check(id)) { + PyErr_SetString(PyExc_TypeError, "ID must be an int"); + return NULL; + } + + PyInterpreterState *interp = _look_up(id); + if (interp == NULL) { + return NULL; + } + int is_running = _is_running(interp); + if (is_running < 0) { + return NULL; + } + if (is_running) { + Py_RETURN_TRUE; + } + Py_RETURN_FALSE; +} + +PyDoc_STRVAR(is_running_doc, +"is_running(id) -> bool\n\ +\n\ +Return whether or not the identified interpreter is running."); + +static PyObject * +channel_create(PyObject *self) +{ + int64_t cid = _channel_create(&_globals.channels); + if (cid < 0) { + return NULL; + } + PyObject *id = (PyObject *)newchannelid(&ChannelIDtype, cid, 0, + &_globals.channels, 0); + if (id == NULL) { + if (_channel_destroy(&_globals.channels, cid) != 0) { + // XXX issue a warning? + } + return NULL; + } + assert(((channelid *)id)->channels != NULL); + return id; +} + +PyDoc_STRVAR(channel_create_doc, +"channel_create() -> ID\n\ +\n\ +Create a new cross-interpreter channel and return a unique generated ID."); + +static PyObject * +channel_destroy(PyObject *self, PyObject *args) +{ + PyObject *id; + if (!PyArg_UnpackTuple(args, "channel_destroy", 1, 1, &id)) { + return NULL; + } + int64_t cid = _coerce_id(id); + if (cid < 0) { + return NULL; + } + + if (_channel_destroy(&_globals.channels, cid) != 0) { + return NULL; + } + Py_RETURN_NONE; +} + +PyDoc_STRVAR(channel_destroy_doc, +"channel_destroy(ID)\n\ +\n\ +Close and finalize the channel. Afterward attempts to use the channel\n\ +will behave as though it never existed."); + +static PyObject * +channel_list_all(PyObject *self) +{ + int64_t count = 0; + int64_t *cids = _channels_list_all(&_globals.channels, &count); + if (cids == NULL) { + if (count == 0) { + return PyList_New(0); + } + return NULL; + } + PyObject *ids = PyList_New((Py_ssize_t)count); + if (ids == NULL) { + // XXX free cids + return NULL; + } + for (int64_t i=0; i < count; cids++, i++) { + PyObject *id = (PyObject *)newchannelid(&ChannelIDtype, *cids, 0, + &_globals.channels, 0); + if (id == NULL) { + Py_DECREF(ids); + ids = NULL; + break; + } + PyList_SET_ITEM(ids, i, id); + } + // XXX free cids + return ids; +} + +PyDoc_STRVAR(channel_list_all_doc, +"channel_list_all() -> [ID]\n\ +\n\ +Return the list of all IDs for active channels."); + +static PyObject * +channel_send(PyObject *self, PyObject *args) +{ + PyObject *id; + PyObject *obj; + if (!PyArg_UnpackTuple(args, "channel_send", 2, 2, &id, &obj)) { + return NULL; + } + int64_t cid = _coerce_id(id); + if (cid < 0) { + return NULL; + } + + if (_channel_send(&_globals.channels, cid, obj) != 0) { + return NULL; + } + Py_RETURN_NONE; +} + +PyDoc_STRVAR(channel_send_doc, +"channel_send(ID, obj)\n\ +\n\ +Add the object's data to the channel's queue."); + +static PyObject * +channel_recv(PyObject *self, PyObject *args) +{ + PyObject *id; + if (!PyArg_UnpackTuple(args, "channel_recv", 1, 1, &id)) { + return NULL; + } + int64_t cid = _coerce_id(id); + if (cid < 0) { + return NULL; + } + + return _channel_recv(&_globals.channels, cid); +} + +PyDoc_STRVAR(channel_recv_doc, +"channel_recv(ID) -> obj\n\ +\n\ +Return a new object from the data at the from of the channel's queue."); + +static PyObject * +channel_close(PyObject *self, PyObject *args, PyObject *kwds) +{ + PyObject *id; + if (!PyArg_UnpackTuple(args, "channel_recv", 1, 1, &id)) { + return NULL; + } + int64_t cid = _coerce_id(id); + if (cid < 0) { + return NULL; + } + + if (_channel_close(&_globals.channels, cid) != 0) { + return NULL; + } + Py_RETURN_NONE; +} + +PyDoc_STRVAR(channel_close_doc, +"channel_close(ID)\n\ +\n\ +Close the channel for all interpreters. Once the channel's ID has\n\ +no more ref counts the channel will be destroyed."); + +static PyObject * +channel_drop_interpreter(PyObject *self, PyObject *args, PyObject *kwds) +{ + // Note that only the current interpreter is affected. + static char *kwlist[] = {"id", "send", "recv"}; + PyObject *id; + int send = -1; + int recv = -1; + if (!PyArg_ParseTupleAndKeywords(args, kwds, + "O|$pp:channel_drop_interpreter", kwlist, + &id, &send, &recv)) + return NULL; + + int64_t cid = _coerce_id(id); + if (cid < 0) { + return NULL; + } + if (send < 0 && recv < 0) { + send = 1; + recv = 1; + } + else { + if (send < 0) { + send = 0; + } + if (recv < 0) { + recv = 0; + } + } + if (_channel_drop(&_globals.channels, cid, send, recv) != 0) { + return NULL; + } + Py_RETURN_NONE; +} + +PyDoc_STRVAR(channel_drop_interpreter_doc, +"channel_drop_interpreter(ID, *, send=None, recv=None)\n\ +\n\ +Close the channel for the current interpreter. 'send' and 'recv'\n\ +(bool) may be used to indicate the ends to close. By default both\n\ +ends are closed. Closing an already closed end is a noop."); + +static PyObject * +channel__channel_id(PyObject *self, PyObject *args, PyObject *kwds) +{ + return channelid_new(&ChannelIDtype, args, kwds); +} + +static PyMethodDef module_functions[] = { + {"create", (PyCFunction)interp_create, + METH_VARARGS, create_doc}, + {"destroy", (PyCFunction)interp_destroy, + METH_VARARGS, destroy_doc}, + {"list_all", (PyCFunction)interp_list_all, + METH_NOARGS, list_all_doc}, + {"get_current", (PyCFunction)interp_get_current, + METH_NOARGS, get_current_doc}, + {"get_main", (PyCFunction)interp_get_main, + METH_NOARGS, get_main_doc}, + {"is_running", (PyCFunction)interp_is_running, + METH_VARARGS, is_running_doc}, + {"run_string", (PyCFunction)interp_run_string, + METH_VARARGS, run_string_doc}, + + {"is_shareable", (PyCFunction)object_is_shareable, + METH_VARARGS, is_shareable_doc}, + + {"channel_create", (PyCFunction)channel_create, + METH_NOARGS, channel_create_doc}, + {"channel_destroy", (PyCFunction)channel_destroy, + METH_VARARGS, channel_destroy_doc}, + {"channel_list_all", (PyCFunction)channel_list_all, + METH_NOARGS, channel_list_all_doc}, + {"channel_send", (PyCFunction)channel_send, + METH_VARARGS, channel_send_doc}, + {"channel_recv", (PyCFunction)channel_recv, + METH_VARARGS, channel_recv_doc}, + {"channel_close", (PyCFunction)channel_close, + METH_VARARGS, channel_close_doc}, + {"channel_drop_interpreter", (PyCFunction)channel_drop_interpreter, + METH_VARARGS | METH_KEYWORDS, channel_drop_interpreter_doc}, + {"_channel_id", (PyCFunction)channel__channel_id, + METH_VARARGS | METH_KEYWORDS, NULL}, + + {NULL, NULL} /* sentinel */ +}; + + +/* initialization function */ + +PyDoc_STRVAR(module_doc, +"This module provides primitive operations to manage Python interpreters.\n\ +The 'interpreters' module provides a more convenient interface."); + +static struct PyModuleDef interpretersmodule = { + PyModuleDef_HEAD_INIT, + "_xxsubinterpreters", /* m_name */ + module_doc, /* m_doc */ + -1, /* m_size */ + module_functions, /* m_methods */ + NULL, /* m_slots */ + NULL, /* m_traverse */ + NULL, /* m_clear */ + NULL /* m_free */ +}; + + +PyMODINIT_FUNC +PyInit__xxsubinterpreters(void) +{ + if (_init_globals() != 0) { + return NULL; + } + + /* Initialize types */ + ChannelIDtype.tp_base = &PyLong_Type; + if (PyType_Ready(&ChannelIDtype) != 0) { + return NULL; + } + + /* Create the module */ + PyObject *module = PyModule_Create(&interpretersmodule); + if (module == NULL) { + return NULL; + } + + /* Add exception types */ + PyObject *ns = PyModule_GetDict(module); // borrowed + if (interp_exceptions_init(ns) != 0) { + return NULL; + } + if (channel_exceptions_init(ns) != 0) { + return NULL; + } + + /* Add other types */ + Py_INCREF(&ChannelIDtype); + if (PyDict_SetItemString(ns, "ChannelID", (PyObject *)&ChannelIDtype) != 0) { + return NULL; + } + + if (_PyCrossInterpreterData_Register_Class(&ChannelIDtype, _channelid_shared)) { + return NULL; + } + + return module; +} diff --git a/Python/pystate.c b/Python/pystate.c index 909d831465d..a474549a8c7 100644 --- a/Python/pystate.c +++ b/Python/pystate.c @@ -54,8 +54,13 @@ _PyRuntimeState_Init_impl(_PyRuntimeState *runtime) if (runtime->interpreters.mutex == NULL) { return _Py_INIT_ERR("Can't initialize threads for interpreter"); } - runtime->interpreters.next_id = -1; + + runtime->xidregistry.mutex = PyThread_allocate_lock(); + if (runtime->xidregistry.mutex == NULL) { + return _Py_INIT_ERR("Can't initialize threads for cross-interpreter data registry"); + } + return _Py_INIT_OK(); } @@ -166,6 +171,7 @@ PyInterpreterState_New(void) /* overflow or Py_Initialize() not called! */ PyErr_SetString(PyExc_RuntimeError, "failed to get an interpreter ID"); + /* XXX deallocate! */ interp = NULL; } else { interp->id = _PyRuntime.interpreters.next_id; @@ -256,6 +262,28 @@ PyInterpreterState_GetID(PyInterpreterState *interp) } +PyInterpreterState * +_PyInterpreterState_LookUpID(PY_INT64_T requested_id) +{ + if (requested_id < 0) + goto error; + + PyInterpreterState *interp = PyInterpreterState_Head(); + while (interp != NULL) { + PY_INT64_T id = PyInterpreterState_GetID(interp); + if (id < 0) + return NULL; + if (requested_id == id) + return interp; + interp = PyInterpreterState_Next(interp); + } + +error: + PyErr_Format(PyExc_RuntimeError, + "unrecognized interpreter ID %lld", requested_id); + return NULL; +} + /* Default implementation for _PyThreadState_GetFrame */ static struct _frame * threadstate_getframe(PyThreadState *self) @@ -1024,6 +1052,251 @@ PyGILState_Release(PyGILState_STATE oldstate) } +/**************************/ +/* cross-interpreter data */ +/**************************/ + +/* cross-interpreter data */ + +crossinterpdatafunc _PyCrossInterpreterData_Lookup(PyObject *); + +/* This is a separate func from _PyCrossInterpreterData_Lookup in order + to keep the registry code separate. */ +static crossinterpdatafunc +_lookup_getdata(PyObject *obj) +{ + crossinterpdatafunc getdata = _PyCrossInterpreterData_Lookup(obj); + if (getdata == NULL && PyErr_Occurred() == 0) + PyErr_Format(PyExc_ValueError, + "%S does not support cross-interpreter data", obj); + return getdata; +} + +int +_PyObject_CheckCrossInterpreterData(PyObject *obj) +{ + crossinterpdatafunc getdata = _lookup_getdata(obj); + if (getdata == NULL) { + return -1; + } + return 0; +} + +static int +_check_xidata(_PyCrossInterpreterData *data) +{ + // data->data can be anything, including NULL, so we don't check it. + + // data->obj may be NULL, so we don't check it. + + if (data->interp < 0) { + PyErr_SetString(PyExc_SystemError, "missing interp"); + return -1; + } + + if (data->new_object == NULL) { + PyErr_SetString(PyExc_SystemError, "missing new_object func"); + return -1; + } + + // data->free may be NULL, so we don't check it. + + return 0; +} + +int +_PyObject_GetCrossInterpreterData(PyObject *obj, _PyCrossInterpreterData *data) +{ + PyThreadState *tstate = PyThreadState_Get(); + // PyThreadState_Get() aborts if lookup fails, so we don't need + // to check the result for NULL. + PyInterpreterState *interp = tstate->interp; + + // Reset data before re-populating. + *data = (_PyCrossInterpreterData){0}; + data->free = PyMem_RawFree; // Set a default that may be overridden. + + // Call the "getdata" func for the object. + Py_INCREF(obj); + crossinterpdatafunc getdata = _lookup_getdata(obj); + if (getdata == NULL) { + Py_DECREF(obj); + return -1; + } + int res = getdata(obj, data); + Py_DECREF(obj); + if (res != 0) { + return -1; + } + + // Fill in the blanks and validate the result. + Py_XINCREF(data->obj); + data->interp = interp->id; + if (_check_xidata(data) != 0) { + _PyCrossInterpreterData_Release(data); + return -1; + } + + return 0; +} + +void +_PyCrossInterpreterData_Release(_PyCrossInterpreterData *data) +{ + if (data->data == NULL && data->obj == NULL) { + // Nothing to release! + return; + } + + // Switch to the original interpreter. + PyInterpreterState *interp = _PyInterpreterState_LookUpID(data->interp); + if (interp == NULL) { + // The intepreter was already destroyed. + if (data->free != NULL) { + // XXX Someone leaked some memory... + } + return; + } + PyThreadState *tstate = PyInterpreterState_ThreadHead(interp); + PyThreadState *save_tstate = PyThreadState_Swap(tstate); + + // "Release" the data and/or the object. + if (data->free != NULL) { + data->free(data->data); + } + Py_XDECREF(data->obj); + + // Switch back. + if (save_tstate != NULL) + PyThreadState_Swap(save_tstate); +} + +PyObject * +_PyCrossInterpreterData_NewObject(_PyCrossInterpreterData *data) +{ + return data->new_object(data); +} + +/* registry of {type -> crossinterpdatafunc} */ + +/* For now we use a global registry of shareable classes. An + alternative would be to add a tp_* slot for a class's + crossinterpdatafunc. It would be simpler and more efficient. */ + +static int +_register_xidata(PyTypeObject *cls, crossinterpdatafunc getdata) +{ + // Note that we effectively replace already registered classes + // rather than failing. + struct _xidregitem *newhead = PyMem_RawMalloc(sizeof(struct _xidregitem)); + if (newhead == NULL) + return -1; + newhead->cls = cls; + newhead->getdata = getdata; + newhead->next = _PyRuntime.xidregistry.head; + _PyRuntime.xidregistry.head = newhead; + return 0; +} + +static void _register_builtins_for_crossinterpreter_data(void); + +int +_PyCrossInterpreterData_Register_Class(PyTypeObject *cls, + crossinterpdatafunc getdata) +{ + if (!PyType_Check(cls)) { + PyErr_Format(PyExc_ValueError, "only classes may be registered"); + return -1; + } + if (getdata == NULL) { + PyErr_Format(PyExc_ValueError, "missing 'getdata' func"); + return -1; + } + + // Make sure the class isn't ever deallocated. + Py_INCREF((PyObject *)cls); + + PyThread_acquire_lock(_PyRuntime.xidregistry.mutex, WAIT_LOCK); + if (_PyRuntime.xidregistry.head == NULL) { + _register_builtins_for_crossinterpreter_data(); + } + int res = _register_xidata(cls, getdata); + PyThread_release_lock(_PyRuntime.xidregistry.mutex); + return res; +} + +crossinterpdatafunc +_PyCrossInterpreterData_Lookup(PyObject *obj) +{ + PyObject *cls = PyObject_Type(obj); + crossinterpdatafunc getdata = NULL; + PyThread_acquire_lock(_PyRuntime.xidregistry.mutex, WAIT_LOCK); + struct _xidregitem *cur = _PyRuntime.xidregistry.head; + if (cur == NULL) { + _register_builtins_for_crossinterpreter_data(); + cur = _PyRuntime.xidregistry.head; + } + for(; cur != NULL; cur = cur->next) { + if (cur->cls == (PyTypeObject *)cls) { + getdata = cur->getdata; + break; + } + } + PyThread_release_lock(_PyRuntime.xidregistry.mutex); + return getdata; +} + +/* cross-interpreter data for builtin types */ + +static PyObject * +_new_bytes_object(_PyCrossInterpreterData *data) +{ + return PyBytes_FromString((char *)(data->data)); +} + +static int +_bytes_shared(PyObject *obj, _PyCrossInterpreterData *data) +{ + data->data = (void *)(PyBytes_AS_STRING(obj)); + data->obj = obj; // Will be "released" (decref'ed) when data released. + data->new_object = _new_bytes_object; + data->free = NULL; // Do not free the data (it belongs to the object). + return 0; +} + +static PyObject * +_new_none_object(_PyCrossInterpreterData *data) +{ + // XXX Singleton refcounts are problematic across interpreters... + Py_INCREF(Py_None); + return Py_None; +} + +static int +_none_shared(PyObject *obj, _PyCrossInterpreterData *data) +{ + data->data = NULL; + // data->obj remains NULL + data->new_object = _new_none_object; + data->free = NULL; // There is nothing to free. + return 0; +} + +static void +_register_builtins_for_crossinterpreter_data(void) +{ + // None + if (_register_xidata((PyTypeObject *)PyObject_Type(Py_None), _none_shared) != 0) { + Py_FatalError("could not register None for cross-interpreter sharing"); + } + + // bytes + if (_register_xidata(&PyBytes_Type, _bytes_shared) != 0) { + Py_FatalError("could not register bytes for cross-interpreter sharing"); + } +} + + #ifdef __cplusplus } #endif diff --git a/setup.py b/setup.py index ba0a7624cfc..6f9a39719b4 100644 --- a/setup.py +++ b/setup.py @@ -755,6 +755,10 @@ class PyBuildExt(build_ext): ['_xxtestfuzz/_xxtestfuzz.c', '_xxtestfuzz/fuzzer.c']) ) + # Python interface to subinterpreter C-API. + exts.append(Extension('_xxsubinterpreters', ['_xxsubinterpretersmodule.c'], + define_macros=[('Py_BUILD_CORE', '')])) + # # Here ends the simple stuff. From here on, modules need certain # libraries, are platform-specific, or present other surprises.