| |
| /* Thread module */ |
| /* Interface to Sjoerd's portable C thread library */ |
| |
| #include "Python.h" |
| #include "structmember.h" /* offsetof */ |
| |
| #ifndef WITH_THREAD |
| #error "Error! The rest of Python is not compiled with thread support." |
| #error "Rerun configure, adding a --with-threads option." |
| #error "Then run `make clean' followed by `make'." |
| #endif |
| |
| #include "pythread.h" |
| |
| static PyObject *ThreadError; |
| static long nb_threads = 0; |
| static PyObject *str_dict; |
| |
| /* Lock objects */ |
| |
| typedef struct { |
| PyObject_HEAD |
| PyThread_type_lock lock_lock; |
| PyObject *in_weakreflist; |
| } lockobject; |
| |
| static void |
| lock_dealloc(lockobject *self) |
| { |
| if (self->in_weakreflist != NULL) |
| PyObject_ClearWeakRefs((PyObject *) self); |
| if (self->lock_lock != NULL) { |
| /* Unlock the lock so it's safe to free it */ |
| PyThread_acquire_lock(self->lock_lock, 0); |
| PyThread_release_lock(self->lock_lock); |
| |
| PyThread_free_lock(self->lock_lock); |
| } |
| PyObject_Del(self); |
| } |
| |
| /* Helper to acquire an interruptible lock with a timeout. If the lock acquire |
| * is interrupted, signal handlers are run, and if they raise an exception, |
| * PY_LOCK_INTR is returned. Otherwise, PY_LOCK_ACQUIRED or PY_LOCK_FAILURE |
| * are returned, depending on whether the lock can be acquired withing the |
| * timeout. |
| */ |
| static PyLockStatus |
| acquire_timed(PyThread_type_lock lock, PY_TIMEOUT_T microseconds) |
| { |
| PyLockStatus r; |
| _PyTime_timeval curtime; |
| _PyTime_timeval endtime; |
| |
| |
| if (microseconds > 0) { |
| _PyTime_gettimeofday(&endtime); |
| endtime.tv_sec += microseconds / (1000 * 1000); |
| endtime.tv_usec += microseconds % (1000 * 1000); |
| } |
| |
| |
| do { |
| Py_BEGIN_ALLOW_THREADS |
| r = PyThread_acquire_lock_timed(lock, microseconds, 1); |
| Py_END_ALLOW_THREADS |
| |
| if (r == PY_LOCK_INTR) { |
| /* Run signal handlers if we were interrupted. Propagate |
| * exceptions from signal handlers, such as KeyboardInterrupt, by |
| * passing up PY_LOCK_INTR. */ |
| if (Py_MakePendingCalls() < 0) { |
| return PY_LOCK_INTR; |
| } |
| |
| /* If we're using a timeout, recompute the timeout after processing |
| * signals, since those can take time. */ |
| if (microseconds > 0) { |
| _PyTime_gettimeofday(&curtime); |
| microseconds = ((endtime.tv_sec - curtime.tv_sec) * 1000000 + |
| (endtime.tv_usec - curtime.tv_usec)); |
| |
| /* Check for negative values, since those mean block forever. |
| */ |
| if (microseconds <= 0) { |
| r = PY_LOCK_FAILURE; |
| } |
| } |
| } |
| } while (r == PY_LOCK_INTR); /* Retry if we were interrupted. */ |
| |
| return r; |
| } |
| |
| static PyObject * |
| lock_PyThread_acquire_lock(lockobject *self, PyObject *args, PyObject *kwds) |
| { |
| char *kwlist[] = {"blocking", "timeout", NULL}; |
| int blocking = 1; |
| double timeout = -1; |
| PY_TIMEOUT_T microseconds; |
| PyLockStatus r; |
| |
| if (!PyArg_ParseTupleAndKeywords(args, kwds, "|id:acquire", kwlist, |
| &blocking, &timeout)) |
| return NULL; |
| |
| if (!blocking && timeout != -1) { |
| PyErr_SetString(PyExc_ValueError, "can't specify a timeout " |
| "for a non-blocking call"); |
| return NULL; |
| } |
| if (timeout < 0 && timeout != -1) { |
| PyErr_SetString(PyExc_ValueError, "timeout value must be " |
| "strictly positive"); |
| return NULL; |
| } |
| if (!blocking) |
| microseconds = 0; |
| else if (timeout == -1) |
| microseconds = -1; |
| else { |
| timeout *= 1e6; |
| if (timeout >= (double) PY_TIMEOUT_MAX) { |
| PyErr_SetString(PyExc_OverflowError, |
| "timeout value is too large"); |
| return NULL; |
| } |
| microseconds = (PY_TIMEOUT_T) timeout; |
| } |
| |
| r = acquire_timed(self->lock_lock, microseconds); |
| if (r == PY_LOCK_INTR) { |
| return NULL; |
| } |
| |
| return PyBool_FromLong(r == PY_LOCK_ACQUIRED); |
| } |
| |
| PyDoc_STRVAR(acquire_doc, |
| "acquire([wait]) -> None or bool\n\ |
| (acquire_lock() is an obsolete synonym)\n\ |
| \n\ |
| Lock the lock. Without argument, this blocks if the lock is already\n\ |
| locked (even by the same thread), waiting for another thread to release\n\ |
| the lock, and return None once the lock is acquired.\n\ |
| With an argument, this will only block if the argument is true,\n\ |
| and the return value reflects whether the lock is acquired.\n\ |
| The blocking operation is interruptible."); |
| |
| static PyObject * |
| lock_PyThread_release_lock(lockobject *self) |
| { |
| /* Sanity check: the lock must be locked */ |
| if (PyThread_acquire_lock(self->lock_lock, 0)) { |
| PyThread_release_lock(self->lock_lock); |
| PyErr_SetString(ThreadError, "release unlocked lock"); |
| return NULL; |
| } |
| |
| PyThread_release_lock(self->lock_lock); |
| Py_INCREF(Py_None); |
| return Py_None; |
| } |
| |
| PyDoc_STRVAR(release_doc, |
| "release()\n\ |
| (release_lock() is an obsolete synonym)\n\ |
| \n\ |
| Release the lock, allowing another thread that is blocked waiting for\n\ |
| the lock to acquire the lock. The lock must be in the locked state,\n\ |
| but it needn't be locked by the same thread that unlocks it."); |
| |
| static PyObject * |
| lock_locked_lock(lockobject *self) |
| { |
| if (PyThread_acquire_lock(self->lock_lock, 0)) { |
| PyThread_release_lock(self->lock_lock); |
| return PyBool_FromLong(0L); |
| } |
| return PyBool_FromLong(1L); |
| } |
| |
| PyDoc_STRVAR(locked_doc, |
| "locked() -> bool\n\ |
| (locked_lock() is an obsolete synonym)\n\ |
| \n\ |
| Return whether the lock is in the locked state."); |
| |
| static PyMethodDef lock_methods[] = { |
| {"acquire_lock", (PyCFunction)lock_PyThread_acquire_lock, |
| METH_VARARGS | METH_KEYWORDS, acquire_doc}, |
| {"acquire", (PyCFunction)lock_PyThread_acquire_lock, |
| METH_VARARGS | METH_KEYWORDS, acquire_doc}, |
| {"release_lock", (PyCFunction)lock_PyThread_release_lock, |
| METH_NOARGS, release_doc}, |
| {"release", (PyCFunction)lock_PyThread_release_lock, |
| METH_NOARGS, release_doc}, |
| {"locked_lock", (PyCFunction)lock_locked_lock, |
| METH_NOARGS, locked_doc}, |
| {"locked", (PyCFunction)lock_locked_lock, |
| METH_NOARGS, locked_doc}, |
| {"__enter__", (PyCFunction)lock_PyThread_acquire_lock, |
| METH_VARARGS | METH_KEYWORDS, acquire_doc}, |
| {"__exit__", (PyCFunction)lock_PyThread_release_lock, |
| METH_VARARGS, release_doc}, |
| {NULL, NULL} /* sentinel */ |
| }; |
| |
| static PyTypeObject Locktype = { |
| PyVarObject_HEAD_INIT(&PyType_Type, 0) |
| "_thread.lock", /*tp_name*/ |
| sizeof(lockobject), /*tp_size*/ |
| 0, /*tp_itemsize*/ |
| /* methods */ |
| (destructor)lock_dealloc, /*tp_dealloc*/ |
| 0, /*tp_print*/ |
| 0, /*tp_getattr*/ |
| 0, /*tp_setattr*/ |
| 0, /*tp_reserved*/ |
| 0, /*tp_repr*/ |
| 0, /*tp_as_number*/ |
| 0, /*tp_as_sequence*/ |
| 0, /*tp_as_mapping*/ |
| 0, /*tp_hash*/ |
| 0, /*tp_call*/ |
| 0, /*tp_str*/ |
| 0, /*tp_getattro*/ |
| 0, /*tp_setattro*/ |
| 0, /*tp_as_buffer*/ |
| Py_TPFLAGS_DEFAULT, /*tp_flags*/ |
| 0, /*tp_doc*/ |
| 0, /*tp_traverse*/ |
| 0, /*tp_clear*/ |
| 0, /*tp_richcompare*/ |
| offsetof(lockobject, in_weakreflist), /*tp_weaklistoffset*/ |
| 0, /*tp_iter*/ |
| 0, /*tp_iternext*/ |
| lock_methods, /*tp_methods*/ |
| }; |
| |
| /* Recursive lock objects */ |
| |
| typedef struct { |
| PyObject_HEAD |
| PyThread_type_lock rlock_lock; |
| long rlock_owner; |
| unsigned long rlock_count; |
| PyObject *in_weakreflist; |
| } rlockobject; |
| |
| static void |
| rlock_dealloc(rlockobject *self) |
| { |
| assert(self->rlock_lock); |
| if (self->in_weakreflist != NULL) |
| PyObject_ClearWeakRefs((PyObject *) self); |
| /* Unlock the lock so it's safe to free it */ |
| if (self->rlock_count > 0) |
| PyThread_release_lock(self->rlock_lock); |
| |
| PyThread_free_lock(self->rlock_lock); |
| Py_TYPE(self)->tp_free(self); |
| } |
| |
| static PyObject * |
| rlock_acquire(rlockobject *self, PyObject *args, PyObject *kwds) |
| { |
| char *kwlist[] = {"blocking", "timeout", NULL}; |
| int blocking = 1; |
| double timeout = -1; |
| PY_TIMEOUT_T microseconds; |
| long tid; |
| PyLockStatus r = PY_LOCK_ACQUIRED; |
| |
| if (!PyArg_ParseTupleAndKeywords(args, kwds, "|id:acquire", kwlist, |
| &blocking, &timeout)) |
| return NULL; |
| |
| if (!blocking && timeout != -1) { |
| PyErr_SetString(PyExc_ValueError, "can't specify a timeout " |
| "for a non-blocking call"); |
| return NULL; |
| } |
| if (timeout < 0 && timeout != -1) { |
| PyErr_SetString(PyExc_ValueError, "timeout value must be " |
| "strictly positive"); |
| return NULL; |
| } |
| if (!blocking) |
| microseconds = 0; |
| else if (timeout == -1) |
| microseconds = -1; |
| else { |
| timeout *= 1e6; |
| if (timeout >= (double) PY_TIMEOUT_MAX) { |
| PyErr_SetString(PyExc_OverflowError, |
| "timeout value is too large"); |
| return NULL; |
| } |
| microseconds = (PY_TIMEOUT_T) timeout; |
| } |
| |
| tid = PyThread_get_thread_ident(); |
| if (self->rlock_count > 0 && tid == self->rlock_owner) { |
| unsigned long count = self->rlock_count + 1; |
| if (count <= self->rlock_count) { |
| PyErr_SetString(PyExc_OverflowError, |
| "Internal lock count overflowed"); |
| return NULL; |
| } |
| self->rlock_count = count; |
| Py_RETURN_TRUE; |
| } |
| |
| if (self->rlock_count > 0 || |
| !PyThread_acquire_lock(self->rlock_lock, 0)) { |
| if (microseconds == 0) { |
| Py_RETURN_FALSE; |
| } |
| r = acquire_timed(self->rlock_lock, microseconds); |
| } |
| if (r == PY_LOCK_ACQUIRED) { |
| assert(self->rlock_count == 0); |
| self->rlock_owner = tid; |
| self->rlock_count = 1; |
| } |
| else if (r == PY_LOCK_INTR) { |
| return NULL; |
| } |
| |
| return PyBool_FromLong(r == PY_LOCK_ACQUIRED); |
| } |
| |
| PyDoc_STRVAR(rlock_acquire_doc, |
| "acquire(blocking=True) -> bool\n\ |
| \n\ |
| Lock the lock. `blocking` indicates whether we should wait\n\ |
| for the lock to be available or not. If `blocking` is False\n\ |
| and another thread holds the lock, the method will return False\n\ |
| immediately. If `blocking` is True and another thread holds\n\ |
| the lock, the method will wait for the lock to be released,\n\ |
| take it and then return True.\n\ |
| (note: the blocking operation is interruptible.)\n\ |
| \n\ |
| In all other cases, the method will return True immediately.\n\ |
| Precisely, if the current thread already holds the lock, its\n\ |
| internal counter is simply incremented. If nobody holds the lock,\n\ |
| the lock is taken and its internal counter initialized to 1."); |
| |
| static PyObject * |
| rlock_release(rlockobject *self) |
| { |
| long tid = PyThread_get_thread_ident(); |
| |
| if (self->rlock_count == 0 || self->rlock_owner != tid) { |
| PyErr_SetString(PyExc_RuntimeError, |
| "cannot release un-acquired lock"); |
| return NULL; |
| } |
| if (--self->rlock_count == 0) { |
| self->rlock_owner = 0; |
| PyThread_release_lock(self->rlock_lock); |
| } |
| Py_RETURN_NONE; |
| } |
| |
| PyDoc_STRVAR(rlock_release_doc, |
| "release()\n\ |
| \n\ |
| Release the lock, allowing another thread that is blocked waiting for\n\ |
| the lock to acquire the lock. The lock must be in the locked state,\n\ |
| and must be locked by the same thread that unlocks it; otherwise a\n\ |
| `RuntimeError` is raised.\n\ |
| \n\ |
| Do note that if the lock was acquire()d several times in a row by the\n\ |
| current thread, release() needs to be called as many times for the lock\n\ |
| to be available for other threads."); |
| |
| static PyObject * |
| rlock_acquire_restore(rlockobject *self, PyObject *arg) |
| { |
| long owner; |
| unsigned long count; |
| int r = 1; |
| |
| if (!PyArg_ParseTuple(arg, "kl:_acquire_restore", &count, &owner)) |
| return NULL; |
| |
| if (!PyThread_acquire_lock(self->rlock_lock, 0)) { |
| Py_BEGIN_ALLOW_THREADS |
| r = PyThread_acquire_lock(self->rlock_lock, 1); |
| Py_END_ALLOW_THREADS |
| } |
| if (!r) { |
| PyErr_SetString(ThreadError, "couldn't acquire lock"); |
| return NULL; |
| } |
| assert(self->rlock_count == 0); |
| self->rlock_owner = owner; |
| self->rlock_count = count; |
| Py_RETURN_NONE; |
| } |
| |
| PyDoc_STRVAR(rlock_acquire_restore_doc, |
| "_acquire_restore(state) -> None\n\ |
| \n\ |
| For internal use by `threading.Condition`."); |
| |
| static PyObject * |
| rlock_release_save(rlockobject *self) |
| { |
| long owner; |
| unsigned long count; |
| |
| if (self->rlock_count == 0) { |
| PyErr_SetString(PyExc_RuntimeError, |
| "cannot release un-acquired lock"); |
| return NULL; |
| } |
| |
| owner = self->rlock_owner; |
| count = self->rlock_count; |
| self->rlock_count = 0; |
| self->rlock_owner = 0; |
| PyThread_release_lock(self->rlock_lock); |
| return Py_BuildValue("kl", count, owner); |
| } |
| |
| PyDoc_STRVAR(rlock_release_save_doc, |
| "_release_save() -> tuple\n\ |
| \n\ |
| For internal use by `threading.Condition`."); |
| |
| |
| static PyObject * |
| rlock_is_owned(rlockobject *self) |
| { |
| long tid = PyThread_get_thread_ident(); |
| |
| if (self->rlock_count > 0 && self->rlock_owner == tid) { |
| Py_RETURN_TRUE; |
| } |
| Py_RETURN_FALSE; |
| } |
| |
| PyDoc_STRVAR(rlock_is_owned_doc, |
| "_is_owned() -> bool\n\ |
| \n\ |
| For internal use by `threading.Condition`."); |
| |
| static PyObject * |
| rlock_new(PyTypeObject *type, PyObject *args, PyObject *kwds) |
| { |
| rlockobject *self; |
| |
| self = (rlockobject *) type->tp_alloc(type, 0); |
| if (self != NULL) { |
| self->rlock_lock = PyThread_allocate_lock(); |
| if (self->rlock_lock == NULL) { |
| type->tp_free(self); |
| PyErr_SetString(ThreadError, "can't allocate lock"); |
| return NULL; |
| } |
| self->in_weakreflist = NULL; |
| self->rlock_owner = 0; |
| self->rlock_count = 0; |
| } |
| |
| return (PyObject *) self; |
| } |
| |
| static PyObject * |
| rlock_repr(rlockobject *self) |
| { |
| return PyUnicode_FromFormat("<%s owner=%ld count=%lu>", |
| Py_TYPE(self)->tp_name, self->rlock_owner, self->rlock_count); |
| } |
| |
| |
| static PyMethodDef rlock_methods[] = { |
| {"acquire", (PyCFunction)rlock_acquire, |
| METH_VARARGS | METH_KEYWORDS, rlock_acquire_doc}, |
| {"release", (PyCFunction)rlock_release, |
| METH_NOARGS, rlock_release_doc}, |
| {"_is_owned", (PyCFunction)rlock_is_owned, |
| METH_NOARGS, rlock_is_owned_doc}, |
| {"_acquire_restore", (PyCFunction)rlock_acquire_restore, |
| METH_O, rlock_acquire_restore_doc}, |
| {"_release_save", (PyCFunction)rlock_release_save, |
| METH_NOARGS, rlock_release_save_doc}, |
| {"__enter__", (PyCFunction)rlock_acquire, |
| METH_VARARGS | METH_KEYWORDS, rlock_acquire_doc}, |
| {"__exit__", (PyCFunction)rlock_release, |
| METH_VARARGS, rlock_release_doc}, |
| {NULL, NULL} /* sentinel */ |
| }; |
| |
| |
| static PyTypeObject RLocktype = { |
| PyVarObject_HEAD_INIT(&PyType_Type, 0) |
| "_thread.RLock", /*tp_name*/ |
| sizeof(rlockobject), /*tp_size*/ |
| 0, /*tp_itemsize*/ |
| /* methods */ |
| (destructor)rlock_dealloc, /*tp_dealloc*/ |
| 0, /*tp_print*/ |
| 0, /*tp_getattr*/ |
| 0, /*tp_setattr*/ |
| 0, /*tp_reserved*/ |
| (reprfunc)rlock_repr, /*tp_repr*/ |
| 0, /*tp_as_number*/ |
| 0, /*tp_as_sequence*/ |
| 0, /*tp_as_mapping*/ |
| 0, /*tp_hash*/ |
| 0, /*tp_call*/ |
| 0, /*tp_str*/ |
| 0, /*tp_getattro*/ |
| 0, /*tp_setattro*/ |
| 0, /*tp_as_buffer*/ |
| Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */ |
| 0, /*tp_doc*/ |
| 0, /*tp_traverse*/ |
| 0, /*tp_clear*/ |
| 0, /*tp_richcompare*/ |
| offsetof(rlockobject, in_weakreflist), /*tp_weaklistoffset*/ |
| 0, /*tp_iter*/ |
| 0, /*tp_iternext*/ |
| rlock_methods, /*tp_methods*/ |
| 0, /* tp_members */ |
| 0, /* tp_getset */ |
| 0, /* tp_base */ |
| 0, /* tp_dict */ |
| 0, /* tp_descr_get */ |
| 0, /* tp_descr_set */ |
| 0, /* tp_dictoffset */ |
| 0, /* tp_init */ |
| PyType_GenericAlloc, /* tp_alloc */ |
| rlock_new /* tp_new */ |
| }; |
| |
| static lockobject * |
| newlockobject(void) |
| { |
| lockobject *self; |
| self = PyObject_New(lockobject, &Locktype); |
| if (self == NULL) |
| return NULL; |
| self->lock_lock = PyThread_allocate_lock(); |
| self->in_weakreflist = NULL; |
| if (self->lock_lock == NULL) { |
| Py_DECREF(self); |
| PyErr_SetString(ThreadError, "can't allocate lock"); |
| return NULL; |
| } |
| return self; |
| } |
| |
| /* Thread-local objects */ |
| |
| #include "structmember.h" |
| |
| /* Quick overview: |
| |
| We need to be able to reclaim reference cycles as soon as possible |
| (both when a thread is being terminated, or a thread-local object |
| becomes unreachable from user data). Constraints: |
| - it must not be possible for thread-state dicts to be involved in |
| reference cycles (otherwise the cyclic GC will refuse to consider |
| objects referenced from a reachable thread-state dict, even though |
| local_dealloc would clear them) |
| - the death of a thread-state dict must still imply destruction of the |
| corresponding local dicts in all thread-local objects. |
| |
| Our implementation uses small "localdummy" objects in order to break |
| the reference chain. These trivial objects are hashable (using the |
| default scheme of identity hashing) and weakrefable. |
| Each thread-state holds a separate localdummy for each local object |
| (as a /strong reference/), |
| and each thread-local object holds a dict mapping /weak references/ |
| of localdummies to local dicts. |
| |
| Therefore: |
| - only the thread-state dict holds a strong reference to the dummies |
| - only the thread-local object holds a strong reference to the local dicts |
| - only outside objects (application- or library-level) hold strong |
| references to the thread-local objects |
| - as soon as a thread-state dict is destroyed, the weakref callbacks of all |
| dummies attached to that thread are called, and destroy the corresponding |
| local dicts from thread-local objects |
| - as soon as a thread-local object is destroyed, its local dicts are |
| destroyed and its dummies are manually removed from all thread states |
| - the GC can do its work correctly when a thread-local object is dangling, |
| without any interference from the thread-state dicts |
| |
| As an additional optimization, each localdummy holds a borrowed reference |
| to the corresponding localdict. This borrowed reference is only used |
| by the thread-local object which has created the localdummy, which should |
| guarantee that the localdict still exists when accessed. |
| */ |
| |
| typedef struct { |
| PyObject_HEAD |
| PyObject *localdict; /* Borrowed reference! */ |
| PyObject *weakreflist; /* List of weak references to self */ |
| } localdummyobject; |
| |
| static void |
| localdummy_dealloc(localdummyobject *self) |
| { |
| if (self->weakreflist != NULL) |
| PyObject_ClearWeakRefs((PyObject *) self); |
| Py_TYPE(self)->tp_free((PyObject*)self); |
| } |
| |
| static PyTypeObject localdummytype = { |
| PyVarObject_HEAD_INIT(NULL, 0) |
| /* tp_name */ "_thread._localdummy", |
| /* tp_basicsize */ sizeof(localdummyobject), |
| /* tp_itemsize */ 0, |
| /* tp_dealloc */ (destructor)localdummy_dealloc, |
| /* tp_print */ 0, |
| /* tp_getattr */ 0, |
| /* tp_setattr */ 0, |
| /* tp_reserved */ 0, |
| /* tp_repr */ 0, |
| /* tp_as_number */ 0, |
| /* tp_as_sequence */ 0, |
| /* tp_as_mapping */ 0, |
| /* tp_hash */ 0, |
| /* tp_call */ 0, |
| /* tp_str */ 0, |
| /* tp_getattro */ 0, |
| /* tp_setattro */ 0, |
| /* tp_as_buffer */ 0, |
| /* tp_flags */ Py_TPFLAGS_DEFAULT, |
| /* tp_doc */ "Thread-local dummy", |
| /* tp_traverse */ 0, |
| /* tp_clear */ 0, |
| /* tp_richcompare */ 0, |
| /* tp_weaklistoffset */ offsetof(localdummyobject, weakreflist) |
| }; |
| |
| |
| typedef struct { |
| PyObject_HEAD |
| PyObject *key; |
| PyObject *args; |
| PyObject *kw; |
| PyObject *weakreflist; /* List of weak references to self */ |
| /* A {localdummy weakref -> localdict} dict */ |
| PyObject *dummies; |
| /* The callback for weakrefs to localdummies */ |
| PyObject *wr_callback; |
| } localobject; |
| |
| /* Forward declaration */ |
| static PyObject *_ldict(localobject *self); |
| static PyObject *_localdummy_destroyed(PyObject *meth_self, PyObject *dummyweakref); |
| |
| /* Create and register the dummy for the current thread. |
| Returns a borrowed reference of the corresponding local dict */ |
| static PyObject * |
| _local_create_dummy(localobject *self) |
| { |
| PyObject *tdict, *ldict = NULL, *wr = NULL; |
| localdummyobject *dummy = NULL; |
| int r; |
| |
| tdict = PyThreadState_GetDict(); |
| if (tdict == NULL) { |
| PyErr_SetString(PyExc_SystemError, |
| "Couldn't get thread-state dictionary"); |
| goto err; |
| } |
| |
| ldict = PyDict_New(); |
| if (ldict == NULL) |
| goto err; |
| dummy = (localdummyobject *) localdummytype.tp_alloc(&localdummytype, 0); |
| if (dummy == NULL) |
| goto err; |
| dummy->localdict = ldict; |
| wr = PyWeakref_NewRef((PyObject *) dummy, self->wr_callback); |
| if (wr == NULL) |
| goto err; |
| |
| /* As a side-effect, this will cache the weakref's hash before the |
| dummy gets deleted */ |
| r = PyDict_SetItem(self->dummies, wr, ldict); |
| if (r < 0) |
| goto err; |
| Py_CLEAR(wr); |
| r = PyDict_SetItem(tdict, self->key, (PyObject *) dummy); |
| if (r < 0) |
| goto err; |
| Py_CLEAR(dummy); |
| |
| Py_DECREF(ldict); |
| return ldict; |
| |
| err: |
| Py_XDECREF(ldict); |
| Py_XDECREF(wr); |
| Py_XDECREF(dummy); |
| return NULL; |
| } |
| |
| static PyObject * |
| local_new(PyTypeObject *type, PyObject *args, PyObject *kw) |
| { |
| localobject *self; |
| PyObject *wr; |
| static PyMethodDef wr_callback_def = { |
| "_localdummy_destroyed", (PyCFunction) _localdummy_destroyed, METH_O |
| }; |
| |
| if (type->tp_init == PyBaseObject_Type.tp_init |
| && ((args && PyObject_IsTrue(args)) |
| || (kw && PyObject_IsTrue(kw)))) { |
| PyErr_SetString(PyExc_TypeError, |
| "Initialization arguments are not supported"); |
| return NULL; |
| } |
| |
| self = (localobject *)type->tp_alloc(type, 0); |
| if (self == NULL) |
| return NULL; |
| |
| Py_XINCREF(args); |
| self->args = args; |
| Py_XINCREF(kw); |
| self->kw = kw; |
| self->key = PyUnicode_FromFormat("thread.local.%p", self); |
| if (self->key == NULL) |
| goto err; |
| |
| self->dummies = PyDict_New(); |
| if (self->dummies == NULL) |
| goto err; |
| |
| /* We use a weak reference to self in the callback closure |
| in order to avoid spurious reference cycles */ |
| wr = PyWeakref_NewRef((PyObject *) self, NULL); |
| if (wr == NULL) |
| goto err; |
| self->wr_callback = PyCFunction_New(&wr_callback_def, wr); |
| Py_DECREF(wr); |
| if (self->wr_callback == NULL) |
| goto err; |
| |
| if (_local_create_dummy(self) == NULL) |
| goto err; |
| |
| return (PyObject *)self; |
| |
| err: |
| Py_DECREF(self); |
| return NULL; |
| } |
| |
| static int |
| local_traverse(localobject *self, visitproc visit, void *arg) |
| { |
| Py_VISIT(self->args); |
| Py_VISIT(self->kw); |
| Py_VISIT(self->dummies); |
| return 0; |
| } |
| |
| static int |
| local_clear(localobject *self) |
| { |
| PyThreadState *tstate; |
| Py_CLEAR(self->args); |
| Py_CLEAR(self->kw); |
| Py_CLEAR(self->dummies); |
| Py_CLEAR(self->wr_callback); |
| /* Remove all strong references to dummies from the thread states */ |
| if (self->key |
| && (tstate = PyThreadState_Get()) |
| && tstate->interp) { |
| for(tstate = PyInterpreterState_ThreadHead(tstate->interp); |
| tstate; |
| tstate = PyThreadState_Next(tstate)) |
| if (tstate->dict && |
| PyDict_GetItem(tstate->dict, self->key)) |
| PyDict_DelItem(tstate->dict, self->key); |
| } |
| return 0; |
| } |
| |
| static void |
| local_dealloc(localobject *self) |
| { |
| /* Weakrefs must be invalidated right now, otherwise they can be used |
| from code called below, which is very dangerous since Py_REFCNT(self) == 0 */ |
| if (self->weakreflist != NULL) |
| PyObject_ClearWeakRefs((PyObject *) self); |
| |
| PyObject_GC_UnTrack(self); |
| |
| local_clear(self); |
| Py_XDECREF(self->key); |
| Py_TYPE(self)->tp_free((PyObject*)self); |
| } |
| |
| /* Returns a borrowed reference to the local dict, creating it if necessary */ |
| static PyObject * |
| _ldict(localobject *self) |
| { |
| PyObject *tdict, *ldict, *dummy; |
| |
| tdict = PyThreadState_GetDict(); |
| if (tdict == NULL) { |
| PyErr_SetString(PyExc_SystemError, |
| "Couldn't get thread-state dictionary"); |
| return NULL; |
| } |
| |
| dummy = PyDict_GetItem(tdict, self->key); |
| if (dummy == NULL) { |
| ldict = _local_create_dummy(self); |
| if (ldict == NULL) |
| return NULL; |
| |
| if (Py_TYPE(self)->tp_init != PyBaseObject_Type.tp_init && |
| Py_TYPE(self)->tp_init((PyObject*)self, |
| self->args, self->kw) < 0) { |
| /* we need to get rid of ldict from thread so |
| we create a new one the next time we do an attr |
| access */ |
| PyDict_DelItem(tdict, self->key); |
| return NULL; |
| } |
| } |
| else { |
| assert(Py_TYPE(dummy) == &localdummytype); |
| ldict = ((localdummyobject *) dummy)->localdict; |
| } |
| |
| return ldict; |
| } |
| |
| static int |
| local_setattro(localobject *self, PyObject *name, PyObject *v) |
| { |
| PyObject *ldict; |
| int r; |
| |
| ldict = _ldict(self); |
| if (ldict == NULL) |
| return -1; |
| |
| r = PyObject_RichCompareBool(name, str_dict, Py_EQ); |
| if (r == 1) { |
| PyErr_Format(PyExc_AttributeError, |
| "'%.50s' object attribute '%U' is read-only", |
| Py_TYPE(self)->tp_name, name); |
| return -1; |
| } |
| if (r == -1) |
| return -1; |
| |
| return _PyObject_GenericSetAttrWithDict((PyObject *)self, name, v, ldict); |
| } |
| |
| static PyObject *local_getattro(localobject *, PyObject *); |
| |
| static PyTypeObject localtype = { |
| PyVarObject_HEAD_INIT(NULL, 0) |
| /* tp_name */ "_thread._local", |
| /* tp_basicsize */ sizeof(localobject), |
| /* tp_itemsize */ 0, |
| /* tp_dealloc */ (destructor)local_dealloc, |
| /* tp_print */ 0, |
| /* tp_getattr */ 0, |
| /* tp_setattr */ 0, |
| /* tp_reserved */ 0, |
| /* tp_repr */ 0, |
| /* tp_as_number */ 0, |
| /* tp_as_sequence */ 0, |
| /* tp_as_mapping */ 0, |
| /* tp_hash */ 0, |
| /* tp_call */ 0, |
| /* tp_str */ 0, |
| /* tp_getattro */ (getattrofunc)local_getattro, |
| /* tp_setattro */ (setattrofunc)local_setattro, |
| /* tp_as_buffer */ 0, |
| /* tp_flags */ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE |
| | Py_TPFLAGS_HAVE_GC, |
| /* tp_doc */ "Thread-local data", |
| /* tp_traverse */ (traverseproc)local_traverse, |
| /* tp_clear */ (inquiry)local_clear, |
| /* tp_richcompare */ 0, |
| /* tp_weaklistoffset */ offsetof(localobject, weakreflist), |
| /* tp_iter */ 0, |
| /* tp_iternext */ 0, |
| /* tp_methods */ 0, |
| /* tp_members */ 0, |
| /* tp_getset */ 0, |
| /* tp_base */ 0, |
| /* tp_dict */ 0, /* internal use */ |
| /* tp_descr_get */ 0, |
| /* tp_descr_set */ 0, |
| /* tp_dictoffset */ 0, |
| /* tp_init */ 0, |
| /* tp_alloc */ 0, |
| /* tp_new */ local_new, |
| /* tp_free */ 0, /* Low-level free-mem routine */ |
| /* tp_is_gc */ 0, /* For PyObject_IS_GC */ |
| }; |
| |
| static PyObject * |
| local_getattro(localobject *self, PyObject *name) |
| { |
| PyObject *ldict, *value; |
| int r; |
| |
| ldict = _ldict(self); |
| if (ldict == NULL) |
| return NULL; |
| |
| r = PyObject_RichCompareBool(name, str_dict, Py_EQ); |
| if (r == 1) { |
| Py_INCREF(ldict); |
| return ldict; |
| } |
| if (r == -1) |
| return NULL; |
| |
| if (Py_TYPE(self) != &localtype) |
| /* use generic lookup for subtypes */ |
| return _PyObject_GenericGetAttrWithDict((PyObject *)self, name, ldict); |
| |
| /* Optimization: just look in dict ourselves */ |
| value = PyDict_GetItem(ldict, name); |
| if (value == NULL) |
| /* Fall back on generic to get __class__ and __dict__ */ |
| return _PyObject_GenericGetAttrWithDict((PyObject *)self, name, ldict); |
| |
| Py_INCREF(value); |
| return value; |
| } |
| |
| /* Called when a dummy is destroyed. */ |
| static PyObject * |
| _localdummy_destroyed(PyObject *localweakref, PyObject *dummyweakref) |
| { |
| PyObject *obj; |
| localobject *self; |
| assert(PyWeakref_CheckRef(localweakref)); |
| obj = PyWeakref_GET_OBJECT(localweakref); |
| if (obj == Py_None) |
| Py_RETURN_NONE; |
| Py_INCREF(obj); |
| assert(PyObject_TypeCheck(obj, &localtype)); |
| /* If the thread-local object is still alive and not being cleared, |
| remove the corresponding local dict */ |
| self = (localobject *) obj; |
| if (self->dummies != NULL) { |
| PyObject *ldict; |
| ldict = PyDict_GetItem(self->dummies, dummyweakref); |
| if (ldict != NULL) { |
| PyDict_DelItem(self->dummies, dummyweakref); |
| } |
| if (PyErr_Occurred()) |
| PyErr_WriteUnraisable(obj); |
| } |
| Py_DECREF(obj); |
| Py_RETURN_NONE; |
| } |
| |
| /* Module functions */ |
| |
| struct bootstate { |
| PyInterpreterState *interp; |
| PyObject *func; |
| PyObject *args; |
| PyObject *keyw; |
| PyThreadState *tstate; |
| }; |
| |
| static void |
| t_bootstrap(void *boot_raw) |
| { |
| struct bootstate *boot = (struct bootstate *) boot_raw; |
| PyThreadState *tstate; |
| PyObject *res; |
| |
| tstate = boot->tstate; |
| tstate->thread_id = PyThread_get_thread_ident(); |
| _PyThreadState_Init(tstate); |
| PyEval_AcquireThread(tstate); |
| nb_threads++; |
| res = PyEval_CallObjectWithKeywords( |
| boot->func, boot->args, boot->keyw); |
| if (res == NULL) { |
| if (PyErr_ExceptionMatches(PyExc_SystemExit)) |
| PyErr_Clear(); |
| else { |
| PyObject *file; |
| PySys_WriteStderr( |
| "Unhandled exception in thread started by "); |
| file = PySys_GetObject("stderr"); |
| if (file != NULL && file != Py_None) |
| PyFile_WriteObject(boot->func, file, 0); |
| else |
| PyObject_Print(boot->func, stderr, 0); |
| PySys_WriteStderr("\n"); |
| PyErr_PrintEx(0); |
| } |
| } |
| else |
| Py_DECREF(res); |
| Py_DECREF(boot->func); |
| Py_DECREF(boot->args); |
| Py_XDECREF(boot->keyw); |
| PyMem_DEL(boot_raw); |
| nb_threads--; |
| PyThreadState_Clear(tstate); |
| PyThreadState_DeleteCurrent(); |
| PyThread_exit_thread(); |
| } |
| |
| static PyObject * |
| thread_PyThread_start_new_thread(PyObject *self, PyObject *fargs) |
| { |
| PyObject *func, *args, *keyw = NULL; |
| struct bootstate *boot; |
| long ident; |
| |
| if (!PyArg_UnpackTuple(fargs, "start_new_thread", 2, 3, |
| &func, &args, &keyw)) |
| return NULL; |
| if (!PyCallable_Check(func)) { |
| PyErr_SetString(PyExc_TypeError, |
| "first arg must be callable"); |
| return NULL; |
| } |
| if (!PyTuple_Check(args)) { |
| PyErr_SetString(PyExc_TypeError, |
| "2nd arg must be a tuple"); |
| return NULL; |
| } |
| if (keyw != NULL && !PyDict_Check(keyw)) { |
| PyErr_SetString(PyExc_TypeError, |
| "optional 3rd arg must be a dictionary"); |
| return NULL; |
| } |
| boot = PyMem_NEW(struct bootstate, 1); |
| if (boot == NULL) |
| return PyErr_NoMemory(); |
| boot->interp = PyThreadState_GET()->interp; |
| boot->func = func; |
| boot->args = args; |
| boot->keyw = keyw; |
| boot->tstate = _PyThreadState_Prealloc(boot->interp); |
| if (boot->tstate == NULL) { |
| PyMem_DEL(boot); |
| return PyErr_NoMemory(); |
| } |
| Py_INCREF(func); |
| Py_INCREF(args); |
| Py_XINCREF(keyw); |
| PyEval_InitThreads(); /* Start the interpreter's thread-awareness */ |
| ident = PyThread_start_new_thread(t_bootstrap, (void*) boot); |
| if (ident == -1) { |
| PyErr_SetString(ThreadError, "can't start new thread"); |
| Py_DECREF(func); |
| Py_DECREF(args); |
| Py_XDECREF(keyw); |
| PyThreadState_Clear(boot->tstate); |
| PyMem_DEL(boot); |
| return NULL; |
| } |
| return PyLong_FromLong(ident); |
| } |
| |
| PyDoc_STRVAR(start_new_doc, |
| "start_new_thread(function, args[, kwargs])\n\ |
| (start_new() is an obsolete synonym)\n\ |
| \n\ |
| Start a new thread and return its identifier. The thread will call the\n\ |
| function with positional arguments from the tuple args and keyword arguments\n\ |
| taken from the optional dictionary kwargs. The thread exits when the\n\ |
| function returns; the return value is ignored. The thread will also exit\n\ |
| when the function raises an unhandled exception; a stack trace will be\n\ |
| printed unless the exception is SystemExit.\n"); |
| |
| static PyObject * |
| thread_PyThread_exit_thread(PyObject *self) |
| { |
| PyErr_SetNone(PyExc_SystemExit); |
| return NULL; |
| } |
| |
| PyDoc_STRVAR(exit_doc, |
| "exit()\n\ |
| (exit_thread() is an obsolete synonym)\n\ |
| \n\ |
| This is synonymous to ``raise SystemExit''. It will cause the current\n\ |
| thread to exit silently unless the exception is caught."); |
| |
| static PyObject * |
| thread_PyThread_interrupt_main(PyObject * self) |
| { |
| PyErr_SetInterrupt(); |
| Py_INCREF(Py_None); |
| return Py_None; |
| } |
| |
| PyDoc_STRVAR(interrupt_doc, |
| "interrupt_main()\n\ |
| \n\ |
| Raise a KeyboardInterrupt in the main thread.\n\ |
| A subthread can use this function to interrupt the main thread." |
| ); |
| |
| static lockobject *newlockobject(void); |
| |
| static PyObject * |
| thread_PyThread_allocate_lock(PyObject *self) |
| { |
| return (PyObject *) newlockobject(); |
| } |
| |
| PyDoc_STRVAR(allocate_doc, |
| "allocate_lock() -> lock object\n\ |
| (allocate() is an obsolete synonym)\n\ |
| \n\ |
| Create a new lock object. See help(LockType) for information about locks."); |
| |
| static PyObject * |
| thread_get_ident(PyObject *self) |
| { |
| long ident; |
| ident = PyThread_get_thread_ident(); |
| if (ident == -1) { |
| PyErr_SetString(ThreadError, "no current thread ident"); |
| return NULL; |
| } |
| return PyLong_FromLong(ident); |
| } |
| |
| PyDoc_STRVAR(get_ident_doc, |
| "get_ident() -> integer\n\ |
| \n\ |
| Return a non-zero integer that uniquely identifies the current thread\n\ |
| amongst other threads that exist simultaneously.\n\ |
| This may be used to identify per-thread resources.\n\ |
| Even though on some platforms threads identities may appear to be\n\ |
| allocated consecutive numbers starting at 1, this behavior should not\n\ |
| be relied upon, and the number should be seen purely as a magic cookie.\n\ |
| A thread's identity may be reused for another thread after it exits."); |
| |
| static PyObject * |
| thread__count(PyObject *self) |
| { |
| return PyLong_FromLong(nb_threads); |
| } |
| |
| PyDoc_STRVAR(_count_doc, |
| "_count() -> integer\n\ |
| \n\ |
| \ |
| Return the number of currently running Python threads, excluding \n\ |
| the main thread. The returned number comprises all threads created\n\ |
| through `start_new_thread()` as well as `threading.Thread`, and not\n\ |
| yet finished.\n\ |
| \n\ |
| This function is meant for internal and specialized purposes only.\n\ |
| In most applications `threading.enumerate()` should be used instead."); |
| |
| static PyObject * |
| thread_stack_size(PyObject *self, PyObject *args) |
| { |
| size_t old_size; |
| Py_ssize_t new_size = 0; |
| int rc; |
| |
| if (!PyArg_ParseTuple(args, "|n:stack_size", &new_size)) |
| return NULL; |
| |
| if (new_size < 0) { |
| PyErr_SetString(PyExc_ValueError, |
| "size must be 0 or a positive value"); |
| return NULL; |
| } |
| |
| old_size = PyThread_get_stacksize(); |
| |
| rc = PyThread_set_stacksize((size_t) new_size); |
| if (rc == -1) { |
| PyErr_Format(PyExc_ValueError, |
| "size not valid: %zd bytes", |
| new_size); |
| return NULL; |
| } |
| if (rc == -2) { |
| PyErr_SetString(ThreadError, |
| "setting stack size not supported"); |
| return NULL; |
| } |
| |
| return PyLong_FromSsize_t((Py_ssize_t) old_size); |
| } |
| |
| PyDoc_STRVAR(stack_size_doc, |
| "stack_size([size]) -> size\n\ |
| \n\ |
| Return the thread stack size used when creating new threads. The\n\ |
| optional size argument specifies the stack size (in bytes) to be used\n\ |
| for subsequently created threads, and must be 0 (use platform or\n\ |
| configured default) or a positive integer value of at least 32,768 (32k).\n\ |
| If changing the thread stack size is unsupported, a ThreadError\n\ |
| exception is raised. If the specified size is invalid, a ValueError\n\ |
| exception is raised, and the stack size is unmodified. 32k bytes\n\ |
| currently the minimum supported stack size value to guarantee\n\ |
| sufficient stack space for the interpreter itself.\n\ |
| \n\ |
| Note that some platforms may have particular restrictions on values for\n\ |
| the stack size, such as requiring a minimum stack size larger than 32kB or\n\ |
| requiring allocation in multiples of the system memory page size\n\ |
| - platform documentation should be referred to for more information\n\ |
| (4kB pages are common; using multiples of 4096 for the stack size is\n\ |
| the suggested approach in the absence of more specific information)."); |
| |
| static PyMethodDef thread_methods[] = { |
| {"start_new_thread", (PyCFunction)thread_PyThread_start_new_thread, |
| METH_VARARGS, start_new_doc}, |
| {"start_new", (PyCFunction)thread_PyThread_start_new_thread, |
| METH_VARARGS, start_new_doc}, |
| {"allocate_lock", (PyCFunction)thread_PyThread_allocate_lock, |
| METH_NOARGS, allocate_doc}, |
| {"allocate", (PyCFunction)thread_PyThread_allocate_lock, |
| METH_NOARGS, allocate_doc}, |
| {"exit_thread", (PyCFunction)thread_PyThread_exit_thread, |
| METH_NOARGS, exit_doc}, |
| {"exit", (PyCFunction)thread_PyThread_exit_thread, |
| METH_NOARGS, exit_doc}, |
| {"interrupt_main", (PyCFunction)thread_PyThread_interrupt_main, |
| METH_NOARGS, interrupt_doc}, |
| {"get_ident", (PyCFunction)thread_get_ident, |
| METH_NOARGS, get_ident_doc}, |
| {"_count", (PyCFunction)thread__count, |
| METH_NOARGS, _count_doc}, |
| {"stack_size", (PyCFunction)thread_stack_size, |
| METH_VARARGS, stack_size_doc}, |
| {NULL, NULL} /* sentinel */ |
| }; |
| |
| |
| /* Initialization function */ |
| |
| PyDoc_STRVAR(thread_doc, |
| "This module provides primitive operations to write multi-threaded programs.\n\ |
| The 'threading' module provides a more convenient interface."); |
| |
| PyDoc_STRVAR(lock_doc, |
| "A lock object is a synchronization primitive. To create a lock,\n\ |
| call the PyThread_allocate_lock() function. Methods are:\n\ |
| \n\ |
| acquire() -- lock the lock, possibly blocking until it can be obtained\n\ |
| release() -- unlock of the lock\n\ |
| locked() -- test whether the lock is currently locked\n\ |
| \n\ |
| A lock is not owned by the thread that locked it; another thread may\n\ |
| unlock it. A thread attempting to lock a lock that it has already locked\n\ |
| will block until another thread unlocks it. Deadlocks may ensue."); |
| |
| static struct PyModuleDef threadmodule = { |
| PyModuleDef_HEAD_INIT, |
| "_thread", |
| thread_doc, |
| -1, |
| thread_methods, |
| NULL, |
| NULL, |
| NULL, |
| NULL |
| }; |
| |
| |
| PyMODINIT_FUNC |
| PyInit__thread(void) |
| { |
| PyObject *m, *d, *timeout_max; |
| |
| /* Initialize types: */ |
| if (PyType_Ready(&localdummytype) < 0) |
| return NULL; |
| if (PyType_Ready(&localtype) < 0) |
| return NULL; |
| if (PyType_Ready(&Locktype) < 0) |
| return NULL; |
| if (PyType_Ready(&RLocktype) < 0) |
| return NULL; |
| |
| /* Create the module and add the functions */ |
| m = PyModule_Create(&threadmodule); |
| if (m == NULL) |
| return NULL; |
| |
| timeout_max = PyFloat_FromDouble(PY_TIMEOUT_MAX / 1000000); |
| if (!timeout_max) |
| return NULL; |
| if (PyModule_AddObject(m, "TIMEOUT_MAX", timeout_max) < 0) |
| return NULL; |
| |
| /* Add a symbolic constant */ |
| d = PyModule_GetDict(m); |
| ThreadError = PyExc_RuntimeError; |
| Py_INCREF(ThreadError); |
| |
| PyDict_SetItemString(d, "error", ThreadError); |
| Locktype.tp_doc = lock_doc; |
| Py_INCREF(&Locktype); |
| PyDict_SetItemString(d, "LockType", (PyObject *)&Locktype); |
| |
| Py_INCREF(&RLocktype); |
| if (PyModule_AddObject(m, "RLock", (PyObject *)&RLocktype) < 0) |
| return NULL; |
| |
| Py_INCREF(&localtype); |
| if (PyModule_AddObject(m, "_local", (PyObject *)&localtype) < 0) |
| return NULL; |
| |
| nb_threads = 0; |
| |
| str_dict = PyUnicode_InternFromString("__dict__"); |
| if (str_dict == NULL) |
| return NULL; |
| |
| /* Initialize the C thread library */ |
| PyThread_init_thread(); |
| return m; |
| } |