mpage [Mon, 5 Feb 2024 21:48:37 +0000 (13:48 -0800)]
gh-114944: Fix race between `_PyParkingLot_Park` and `_PyParkingLot_UnparkAll` when handling interrupts (#114945)
Fix race between `_PyParkingLot_Park` and `_PyParkingLot_UnparkAll` when handling interrupts
There is a potential race when `_PyParkingLot_UnparkAll` is executing in
one thread and another thread is unblocked because of an interrupt in
`_PyParkingLot_Park`. Consider the following scenario:
1. Thread T0 is blocked[^1] in `_PyParkingLot_Park` on address `A`.
2. Thread T1 executes `_PyParkingLot_UnparkAll` on address `A`. It
finds the `wait_entry` for `T0` and unlinks[^2] its list node.
3. Immediately after (2), T0 is woken up due to an interrupt. It
then segfaults trying to unlink[^3] the node that was previously
unlinked in (2).
To fix this we mark each waiter as unparking before releasing the bucket
lock. `_PyParkingLot_Park` will wait to handle the coming wakeup, and not
attempt to unlink the node, when this field is set. `_PyParkingLot_Unpark`
does this already, presumably to handle this case.
Change the somewhat vague "listed below" to "listed in this chapter" in Doc/library/exceptions.rst.
The exceptions are listed in multiple sections after two intermediate sections.
--------- Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
gh-43457: Tkinter: fix design flaws in wm_attributes() (GH-111404)
* When called with a single argument to get a value, it allow to omit
the minus prefix.
* It can be called with keyword arguments to set attributes.
* w.wm_attributes(return_python_dict=True) returns a dict instead of
a tuple (it will be the default in future).
* Setting wantobjects to 0 no longer affects the result.
Terry Jan Reedy [Mon, 5 Feb 2024 01:57:54 +0000 (20:57 -0500)]
gh-114628: Display csv.Error without context (#115005)
When cvs.Error is raised when TypeError is caught,
the TypeError display and 'During handling' note is just noise
with duplicate information. Suppress with 'from None'.
gh-114099: Add test exclusions to support running the test suite on iOS (#114889)
Add test annotations required to run the test suite on iOS (PEP 730).
The majority of the change involve annotating tests that use subprocess,
but are skipped on Emscripten/WASI for other reasons, and including
iOS/tvOS/watchOS under the same umbrella as macOS/darwin checks.
`is_apple` and `is_apple_mobile` test helpers have been added to
identify *any* Apple platform, and "any Apple platform except macOS",
respectively.
Test all integer member types with extreme values and values outside of
the valid range. Test support of integer-like objects. Test warnings for
wrapped out values.
gh-113951: Tkinter: "tag_unbind(tag, sequence, funcid)" now only unbinds "funcid" (GH-113955)
Previously, "tag_unbind(tag, sequence, funcid)" methods of Text and
Canvas widgets destroyed the current binding for "sequence", leaving
"sequence" unbound, and deleted the "funcid" command.
Now they remove only "funcid" from the binding for "sequence", keeping
other commands, and delete the "funcid" command.
They leave "sequence" unbound only if "funcid" was the last bound command.
gh-114388: Fix warnings when assign an unsigned integer member (GH-114391)
* Fix a RuntimeWarning emitted when assign an integer-like value that
is not an instance of int to an attribute that corresponds to a C
struct member of type T_UINT and T_ULONG.
* Fix a double RuntimeWarning emitted when assign a negative integer value
to an attribute that corresponds to a C struct member of type T_UINT.
Ethan Furman [Sun, 4 Feb 2024 15:22:55 +0000 (07:22 -0800)]
gh-114071: [Enum] update docs and code for tuples/subclasses (GH-114871)
Update documentation with `__new__` and `__init__` entries.
Support use of `auto()` in tuple subclasses on member assignment lines. Previously, auto() was only supported on the member definition line either solo or as part of a tuple:
RED = auto()
BLUE = auto(), 'azul'
However, since Python itself supports using tuple subclasses where tuples are expected, e.g.:
from collections import namedtuple
T = namedtuple('T', 'first second third')
def test(one, two, three):
print(one, two, three)
test(*T(4, 5, 6))
# 4 5 6
it made sense to also support tuple subclasses in enum definitions.
Sam Gross [Fri, 2 Feb 2024 13:03:15 +0000 (08:03 -0500)]
gh-114329: Add `PyList_GetItemRef` function (GH-114504)
The new `PyList_GetItemRef` is similar to `PyList_GetItem`, but returns
a strong reference instead of a borrowed reference. Additionally, if the
passed "list" object is not a list, the function sets a `TypeError`
instead of calling `PyErr_BadInternalCall()`.
gh-103820: IDLE: Do not interpret buttons 4/5 as scrolling on non-X11 (GH-103821)
Also fix test_mousewheel: do not skip a check which was broken due to incorrect
delta on Aqua and XQuartz, and probably not because of `.update_idletasks()`.
Sam Gross [Thu, 1 Feb 2024 20:29:19 +0000 (15:29 -0500)]
gh-112529: Remove PyGC_Head from object pre-header in free-threaded build (#114564)
* gh-112529: Remove PyGC_Head from object pre-header in free-threaded build
This avoids allocating space for PyGC_Head in the free-threaded build.
The GC implementation for free-threaded CPython does not use the
PyGC_Head structure.
* The trashcan mechanism uses the `ob_tid` field instead of `_gc_prev`
in the free-threaded build.
* The GDB libpython.py file now determines the offset of the managed
dict field based on whether the running process is a free-threaded
build. Those are identified by the `ob_ref_local` field in PyObject.
* Fixes `_PySys_GetSizeOf()` which incorrectly incorrectly included the
size of `PyGC_Head` in the size of static `PyTypeObject`.
Sam Gross [Thu, 1 Feb 2024 09:26:23 +0000 (04:26 -0500)]
gh-114746: Avoid quadratic behavior in free-threaded GC (GH-114817)
The free-threaded build's GC implementation is non-generational, but was
scheduled as if it were collecting a young generation leading to
quadratic behavior. This increases the minimum threshold and scales it
to the number of live objects as we do for the old generation in the
default build.
Note that the scheduling is still not thread-safe without the GIL. Those
changes will come in later PRs.
A few tests, like "test_sneaky_frame_object" rely on prompt scheduling
of the GC. For now, to keep that test passing, we disable the scaled
threshold after calls like `gc.set_threshold(1, 0, 0)`.
technillogue [Thu, 1 Feb 2024 06:03:58 +0000 (01:03 -0500)]
gh-114364: Fix awkward wording about mmap.mmap.seekable (#114374)
--------- Co-authored-by: Kirill Podoprigora <kirill.bast9@mail.ru> Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu> Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>
Aidan Holm [Thu, 1 Feb 2024 00:42:38 +0000 (08:42 +0800)]
gh-111112: Avoid potential confusion in TCP server example. (#111113)
Improve misleading TCP server docs and example.
socket.recv(), as documented by the Python reference documentation,
returns at most `bufsize` bytes, and the underlying TCP protocol means
there is no guaranteed correspondence between what is sent by the client
and what is received by the server.
This conflation could mislead readers into thinking that TCP is
datagram-based or has similar semantics, which will likely appear to
work for simple cases, but introduce difficult to reproduce bugs.