diff options
| -rw-r--r-- | Lib/asyncio/tasks.py | 30 | ||||
| -rw-r--r-- | Modules/_asynciomodule.c | 45 | ||||
| -rw-r--r-- | Modules/clinic/_asynciomodule.c.h | 19 |
3 files changed, 48 insertions, 46 deletions
diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py index 25a650f..38c2385 100644 --- a/Lib/asyncio/tasks.py +++ b/Lib/asyncio/tasks.py @@ -105,7 +105,7 @@ class Task(futures._PyFuture): # Inherit Python Task implementation else: self._name = str(name) - self._cancel_requested = False + self._num_cancels_requested = 0 self._must_cancel = False self._fut_waiter = None self._coro = coro @@ -198,13 +198,15 @@ class Task(futures._PyFuture): # Inherit Python Task implementation task will be marked as cancelled when the wrapped coroutine terminates with a CancelledError exception (even if cancel() was not called). + + This also increases the task's count of cancellation requests. """ self._log_traceback = False if self.done(): return False - if self._cancel_requested: + self._num_cancels_requested += 1 + if self._num_cancels_requested > 1: return False - self._cancel_requested = True if self._fut_waiter is not None: if self._fut_waiter.cancel(msg=msg): # Leave self._fut_waiter; it may be a Task that @@ -217,14 +219,24 @@ class Task(futures._PyFuture): # Inherit Python Task implementation return True def cancelling(self): - return self._cancel_requested + """Return the count of the task's cancellation requests. + + This count is incremented when .cancel() is called + and may be decremented using .uncancel(). + """ + return self._num_cancels_requested def uncancel(self): - if self._cancel_requested: - self._cancel_requested = False - return True - else: - return False + """Decrement the task's count of cancellation requests. + + This should be used by tasks that catch CancelledError + and wish to continue indefinitely until they are cancelled again. + + Returns the remaining number of cancellation requests. + """ + if self._num_cancels_requested > 0: + self._num_cancels_requested -= 1 + return self._num_cancels_requested def __step(self, exc=None): if self.done(): diff --git a/Modules/_asynciomodule.c b/Modules/_asynciomodule.c index 0d6b21d..8847123 100644 --- a/Modules/_asynciomodule.c +++ b/Modules/_asynciomodule.c @@ -91,7 +91,7 @@ typedef struct { PyObject *task_context; int task_must_cancel; int task_log_destroy_pending; - int task_cancel_requested; + int task_num_cancels_requested; } TaskObj; typedef struct { @@ -2036,7 +2036,7 @@ _asyncio_Task___init___impl(TaskObj *self, PyObject *coro, PyObject *loop, Py_CLEAR(self->task_fut_waiter); self->task_must_cancel = 0; self->task_log_destroy_pending = 1; - self->task_cancel_requested = 0; + self->task_num_cancels_requested = 0; Py_INCREF(coro); Py_XSETREF(self->task_coro, coro); @@ -2191,11 +2191,13 @@ not return True (unless the task was already cancelled). A task will be marked as cancelled when the wrapped coroutine terminates with a CancelledError exception (even if cancel() was not called). + +This also increases the task's count of cancellation requests. [clinic start generated code]*/ static PyObject * _asyncio_Task_cancel_impl(TaskObj *self, PyObject *msg) -/*[clinic end generated code: output=c66b60d41c74f9f1 input=f4ff8e8ffc5f1c00]*/ +/*[clinic end generated code: output=c66b60d41c74f9f1 input=7bb51bf25974c783]*/ { self->task_log_tb = 0; @@ -2203,10 +2205,10 @@ _asyncio_Task_cancel_impl(TaskObj *self, PyObject *msg) Py_RETURN_FALSE; } - if (self->task_cancel_requested) { + self->task_num_cancels_requested += 1; + if (self->task_num_cancels_requested > 1) { Py_RETURN_FALSE; } - self->task_cancel_requested = 1; if (self->task_fut_waiter) { PyObject *res; @@ -2238,51 +2240,40 @@ _asyncio_Task_cancel_impl(TaskObj *self, PyObject *msg) /*[clinic input] _asyncio.Task.cancelling -Return True if the task is in the process of being cancelled. - -This is set once .cancel() is called -and remains set until .uncancel() is called. +Return the count of the task's cancellation requests. -As long as this flag is set, further .cancel() calls will be ignored, -until .uncancel() is called to reset it. +This count is incremented when .cancel() is called +and may be decremented using .uncancel(). [clinic start generated code]*/ static PyObject * _asyncio_Task_cancelling_impl(TaskObj *self) -/*[clinic end generated code: output=803b3af96f917d7e input=c50e50f9c3ca4676]*/ +/*[clinic end generated code: output=803b3af96f917d7e input=b625224d310cbb17]*/ /*[clinic end generated code]*/ { - if (self->task_cancel_requested) { - Py_RETURN_TRUE; - } - else { - Py_RETURN_FALSE; - } + return PyLong_FromLong(self->task_num_cancels_requested); } /*[clinic input] _asyncio.Task.uncancel -Reset the flag returned by cancelling(). +Decrement the task's count of cancellation requests. This should be used by tasks that catch CancelledError and wish to continue indefinitely until they are cancelled again. -Returns the previous value of the flag. +Returns the remaining number of cancellation requests. [clinic start generated code]*/ static PyObject * _asyncio_Task_uncancel_impl(TaskObj *self) -/*[clinic end generated code: output=58184d236a817d3c input=5db95e28fcb6f7cd]*/ +/*[clinic end generated code: output=58184d236a817d3c input=68f81a4b90b46be2]*/ /*[clinic end generated code]*/ { - if (self->task_cancel_requested) { - self->task_cancel_requested = 0; - Py_RETURN_TRUE; - } - else { - Py_RETURN_FALSE; + if (self->task_num_cancels_requested > 0) { + self->task_num_cancels_requested -= 1; } + return PyLong_FromLong(self->task_num_cancels_requested); } /*[clinic input] diff --git a/Modules/clinic/_asynciomodule.c.h b/Modules/clinic/_asynciomodule.c.h index 5648e14..2b84ef0 100644 --- a/Modules/clinic/_asynciomodule.c.h +++ b/Modules/clinic/_asynciomodule.c.h @@ -414,7 +414,9 @@ PyDoc_STRVAR(_asyncio_Task_cancel__doc__, "not return True (unless the task was already cancelled). A\n" "task will be marked as cancelled when the wrapped coroutine\n" "terminates with a CancelledError exception (even if cancel()\n" -"was not called)."); +"was not called).\n" +"\n" +"This also increases the task\'s count of cancellation requests."); #define _ASYNCIO_TASK_CANCEL_METHODDEF \ {"cancel", (PyCFunction)(void(*)(void))_asyncio_Task_cancel, METH_FASTCALL|METH_KEYWORDS, _asyncio_Task_cancel__doc__}, @@ -451,13 +453,10 @@ PyDoc_STRVAR(_asyncio_Task_cancelling__doc__, "cancelling($self, /)\n" "--\n" "\n" -"Return True if the task is in the process of being cancelled.\n" -"\n" -"This is set once .cancel() is called\n" -"and remains set until .uncancel() is called.\n" +"Return the count of the task\'s cancellation requests.\n" "\n" -"As long as this flag is set, further .cancel() calls will be ignored,\n" -"until .uncancel() is called to reset it."); +"This count is incremented when .cancel() is called\n" +"and may be decremented using .uncancel()."); #define _ASYNCIO_TASK_CANCELLING_METHODDEF \ {"cancelling", (PyCFunction)_asyncio_Task_cancelling, METH_NOARGS, _asyncio_Task_cancelling__doc__}, @@ -475,12 +474,12 @@ PyDoc_STRVAR(_asyncio_Task_uncancel__doc__, "uncancel($self, /)\n" "--\n" "\n" -"Reset the flag returned by cancelling().\n" +"Decrement the task\'s count of cancellation requests.\n" "\n" "This should be used by tasks that catch CancelledError\n" "and wish to continue indefinitely until they are cancelled again.\n" "\n" -"Returns the previous value of the flag."); +"Returns the remaining number of cancellation requests."); #define _ASYNCIO_TASK_UNCANCEL_METHODDEF \ {"uncancel", (PyCFunction)_asyncio_Task_uncancel, METH_NOARGS, _asyncio_Task_uncancel__doc__}, @@ -918,4 +917,4 @@ _asyncio__leave_task(PyObject *module, PyObject *const *args, Py_ssize_t nargs, exit: return return_value; } -/*[clinic end generated code: output=c02708a9d6a774cc input=a9049054013a1b77]*/ +/*[clinic end generated code: output=344927e9b6016ad7 input=a9049054013a1b77]*/ |