Update gevent to 23.9.1

[pyup-bot]

This PR updates gevent from 1.4.0 to 23.9.1.

Changelog

23.9.1

===================


Bugfixes
--------

- Require greenlet 3.0 on Python 3.11 and Python 3.12; greenlet 3.0 is
recommended for all platforms. This fixes a number of obscure crashes
on all versions of Python, as well as fixing a fairly common problem
on Python 3.11+ that could manifest as either a crash or as a
``SystemError``.
See :issue:`1985`.


----

23.9.0.post1

=========================

- Fix Windows wheel builds.
- Fix macOS wheel builds.

23.9.0

===================


Bugfixes
--------

- Make ``gevent.select.select`` accept arbitrary iterables, not just
sequences. That is, you can now pass in a generator of file
descriptors instead of a realized list. Internally, arbitrary
iterables are copied into lists. This better matches what the standard
library does. Thanks to David Salvisberg.
See :issue:`1979`.
- On Python 3.11 and newer, opt out of Cython's fast exception
manipulation, which *may* be causing problems in certain circumstances
when combined with greenlets.

On all versions of Python, adjust some error handling in the default
C-based loop. This fixes several assertion failures on debug versions
of CPython. Hopefully it has a positive impact under real conditions.
See :issue:`1985`.
- Make ``gevent.pywsgi`` comply more closely with the HTTP specification
for chunked transfer encoding. In particular, we are much stricter
about trailers, and trailers that are invalid (too long or featuring
disallowed characters) forcibly close the connection to the client
*after* the results have been sent.

Trailers otherwise continue to be ignored and are not available to the
WSGI application.

Previously, carefully crafted invalid trailers in chunked requests on
keep-alive connections might appear as two requests to
``gevent.pywsgi``. Because this was handled exactly as a normal
keep-alive connection with two requests, the WSGI application should
handle it normally. However, if you were counting on some upstream
server to filter incoming requests based on paths or header fields,
and the upstream server simply passed trailers through without
validating them, then this embedded second request would bypass those
checks. (If the upstream server validated that the trailers meet the
HTTP specification, this could not occur, because characters that are
required in an HTTP request, like a space, are not allowed in
trailers.) CVE-2023-41419 was reserved for this.

Our thanks to the original reporters, Keran Mu
(mkr22mails.tsinghua.edu.cn) and Jianjun Chen
(jianjuntsinghua.edu.cn), from Tsinghua University and Zhongguancun
Laboratory.
See :issue:`1989`.


----

23.7.0

===================


Features
--------

- Add preliminary support for Python 3.12, using greenlet 3.0a1. This
is somewhat tricky to build from source at this time, and there is
one known issue: On Python 3.12b3, dumping tracebacks of greenlets
is not available.
:issue:`1969`.
- Update the bundled c-ares version to 1.19.1.
See :issue:`1947`.


Bugfixes
--------

- Fix an edge case connecting a non-blocking ``SSLSocket`` that could result
in an AttributeError. In a change to match the standard library,
calling ``sock.connect_ex()`` on a subclass of ``socket`` no longer
calls the subclass's ``connect`` method.

Initial fix by Priyankar Jain.
See :issue:`1932`.
- Make gevent's ``FileObjectThread`` (mostly used on Windows) implement
``readinto`` cooperatively. PR by Kirill Smelkov.
See :issue:`1948`.
- Work around an ``AttributeError`` during cyclic garbage collection
when Python finalizers (``__del__`` and the like) attempt to use
gevent APIs. This is not a recommended practice, and it is unclear if
catching this ``AttributeError`` will fix any problems or just shift
them. (If we could determine the root situation that results in this
cycle, we might be able to solve it.)
See :issue:`1961`.


Deprecations and Removals
-------------------------

- Remove support for obsolete Python versions. This is everything prior
to 3.8.

Related changes include:

- Stop using ``pkg_resources`` to find entry points (plugins).
 Instead, use ``importlib.metadata``.
- Honor ``sys.unraisablehook`` when a callback function produces an
 exception, and handling the exception in the hub *also* produces an
 exception. In older versions, these would be simply printed.
- ``setup.py`` no longer includes the ``setup_requires`` keyword.
 Installation with a tool that understands ``pyproject.toml`` is
 recommended.
- The bundled tblib has been updated to version 2.0.


----

22.10.2

====================


Bugfixes
--------

- Update to greenlet 2.0. This fixes a deallocation issue that required
a change in greenlet's ABI. The design of greenlet 2.0 is intended to
prevent future fixes and enhancements from requiring an ABI change,
making it easier to update gevent and greenlet independently.

.. caution::

  greenlet 2.0 requires a modern-ish C++ compiler. This may mean
  certain older platforms are no longer supported.
  See :issue:`1909`.


----

22.10.1

====================


Features
--------

- Update bundled libuv to 1.44.2.
See :issue:`1913`.


Misc
----

- See :issue:`1898`., See :issue:`1910`., See :issue:`1915`.


----

22.08.0

====================


Features
--------

- Windows: Test and provide binary wheels for PyPy3.7.

Note that there may be issues with subprocesses, signals, and it may
be slow.
See :issue:`1798`.
- Upgrade embedded c-ares to 1.18.1.
See :issue:`1847`.
- Upgrade bundled libuv to 1.42.0 from 1.40.0.
See :issue:`1851`.
- Added preliminary support for Python 3.11 (rc2 and later).

Some platforms may or may not have binary wheels at this time.

.. important:: Support for legacy versions of Python, including 2.7
              and 3.6, will be ending soon. The
              maintenance burden has become too great and the
              maintainer's time is too limited.

              Ideally, there will be a release of gevent compatible
              with a final release of greenlet 2.0 that still
              supports those legacy versions, but that may not be
              possible; this may be the final release to support them.

:class:`gevent.threadpool.ThreadPool` can now optionally expire idle
threads. This is used by default in the implicit thread pool used for
DNS requests and other user-submitted tasks; other uses of a
thread-pool need to opt-in to this.
See :issue:`1867`.


Bugfixes
--------

- Truly disable the effects of compiling with ``-ffast-math``.
See :issue:`1864`.


----

21.12.0

====================


Features
--------

- Update autoconf files for Apple Silicon Macs. Note that while there
are reports of compiling gevent on Apple Silicon Macs now, this is
*not* a tested configuration. There may be some remaining issues with
CFFI on some systems as well.
See :issue:`1721`.
- Build and upload CPython 3.10 binary manylinux wheels.

Unfortunately, this required us to stop building and uploading CPython
2.7 binary manylinux wheels. Binary wheels for 2.7 continue to be
available for Windows and macOS.
See :issue:`1822`.
- Test and distribute musllinux_1_1 wheels.
See :issue:`1837`.
- Update the tested versions of PyPy2 and PyPy3. For PyPy2, there should
be no user visible changes, but for PyPy3, support has moved from
Python 3.6 to Python 3.7.
See :issue:`1843`.


Bugfixes
--------

- Try to avoid linking to two different Python runtime DLLs on Windows.
See :issue:`1814`.
- Stop compiling manylinux wheels with ``-ffast-math.`` This was
implicit in ``-Ofast``, but could alter the global state of the
process. Analysis and fix thanks to Ilya Konstantinov.
See :issue:`1820`.
- Fix hanging the interpreter on shutdown if gevent monkey patching
occurred on a non-main thread in Python 3.9.8 and above. (Note that
this is not a recommended practice.)
See :issue:`1839`.


----

21.8.0

===================


Features
--------

- Update the embedded c-ares from 1.16.1 to 1.17.1.
See :issue:`1758`.
- Add support for Python 3.10rc1 and newer.

As part of this, the minimum required greenlet version was increased
to 1.1.0 (on CPython), and the minimum version of Cython needed to
build gevent from a source checkout is 3.0a9.

Note that the dnspython resolver is not available on Python 3.10.
See :issue:`1790`.
- Update from Cython 3.0a6 to 3.0a9.
See :issue:`1801`.


Misc
----

- See :issue:`1789`.


----

21.1.2

===================


Features
--------

- Update the embedded libev from 4.31 to 4.33.
See :issue:`1754`.
- Update the embedded libuv from 1.38.0 to 1.40.0.
See :issue:`1755`.


Misc
----

- See :issue:`1753`.


----

21.1.1

===================

Bugfixes
--------

Fix a ``TypeError`` on startup on Python 2 with ``zope.schema``
installed. Reported by Josh Zuech.

21.1.0

===================

Bugfixes
--------

- Make gevent ``FileObjects`` more closely match the semantics of native
file objects for the ``name`` attribute:

- Objects opened from a file descriptor integer have that integer as
 their ``name.`` (Note that this is the Python 3 semantics; Python 2
 native file objects returned from ``os.fdopen()`` have the string
 "<fdopen>" as their name , but here gevent always follows Python 3.)
- The ``name`` remains accessible after the file object is closed.

Thanks to Dan Milon.
See :issue:`1745`.


Misc
----

Make ``gevent.event.AsyncResult`` print a warning when it detects improper
cross-thread usage instead of hanging.

``AsyncResult`` has *never* been safe to use from multiple threads.
It, like most gevent objects, is intended to work with greenlets from
a single thread. Using ``AsyncResult`` from multiple threads has
undefined semantics. The safest way to communicate between threads is
using an event loop async watcher.

Those undefined semantics changed in recent gevent versions, making it
more likely that an abused ``AsyncResult`` would misbehave in ways
that could cause the program to hang.

Now, when ``AsyncResult`` detects a situation that would hang, it
prints a warning to stderr. Note that this is best-effort, and hangs
are still possible, especially under PyPy 7.3.3.

At the same time, ``AsyncResult`` is tuned to behave more like it did
in older versions, meaning that the hang is once again much less
likely. If you were getting lucky and using ``AsyncResult``
successfully across threads, this may restore your luck. In addition,
cross-thread wakeups are faster. Note that the gevent hub now uses an
extra file descriptor to implement this.

Similar changes apply to ``gevent.event.Event`` (see :issue:`1735`).

See :issue:`1739`.


----

20.12.1

====================


Features
--------

- Make :class:`gevent.Greenlet` objects function as context managers.
When the ``with`` suite finishes, execution doesn't continue until the
greenlet is finished. This can be a simpler alternative to a
:class:`gevent.pool.Group` when the lifetime of greenlets can be
lexically scoped.

Suggested by André Caron.
See :issue:`1324`.


Bugfixes
--------

- Make gevent's ``Semaphore`` objects properly handle native thread
identifiers larger than can be stored in a C ``long`` on Python 3,
instead of raising an ``OverflowError``.

Reported by TheYOSH.
See :issue:`1733`.


----

20.12.0

====================


Features
--------

- Make worker threads created by :class:`gevent.threadpool.ThreadPool` install
the :func:`threading.setprofile` and :func:`threading.settrace` hooks
while tasks are running. This provides visibility to profiling and
tracing tools like yappi.

Reported by Suhail Muhammed.
See :issue:`1678`.

- Drop support for Python 3.5.

Bugfixes
--------

- Incorrectly passing an exception *instance* instead of an exception
*type* to `gevent.Greenlet.kill` or `gevent.killall` no longer prints
an exception to stderr.
See :issue:`1663`.
- Make destroying a hub try harder to more forcibly stop loop processing
when there are outstanding callbacks or IO operations scheduled.

Thanks to Josh Snyder (:issue:`1686`) and Jan-Philip Gehrcke
(:issue:`1669`).
See :issue:`1686`.
- Improve the ability to use monkey-patched locks, and
`gevent.lock.BoundedSemaphore`, across threads, especially when the
various threads might not have a gevent hub or any other active
greenlets. In particular, this handles some cases that previously
raised ``LoopExit`` or would hang. Note that this may not be reliable
on PyPy on Windows; such an environment is not currently recommended.

The semaphore tries to avoid creating a hub if it seems unnecessary,
automatically creating one in the single-threaded case when it would
block, but not in the multi-threaded case. While the differences
should be correctly detected, it's possible there are corner cases
where they might not be.

If your application appears to hang acquiring semaphores, but adding a
call to ``gevent.get_hub()`` in the thread attempting to acquire the
semaphore before doing so fixes it, please file an issue.
See :issue:`1698`.
- Make error reporting when a greenlet suffers a `RecursionError` more
reliable.

Reported by Dan Milon.
See :issue:`1704`.
- gevent.pywsgi: Avoid printing an extra traceback ("TypeError: not
enough arguments for format string") to standard error on certain
invalid client requests.

Reported by Steven Grimm.
See :issue:`1708`.
- Add support for PyPy2 7.3.3.
See :issue:`1709`.
- Python 2: Make ``gevent.subprocess.Popen.stdin`` objects have a
``write`` method that guarantees to write the entire argument in
binary, unbuffered mode. This may require multiple trips around the
event loop, but more closely matches the behaviour of the Python 2
standard library (and gevent prior to 1.5). The number of bytes
written is still returned (instead of ``None``).
See :issue:`1711`.
- Make `gevent.pywsgi` stop trying to enforce the rules for reading chunked input or
``Content-Length`` terminated input when the connection is being
upgraded, for example to a websocket connection. Likewise, if the
protocol was switched by returning a ``101`` status, stop trying to
automatically chunk the responses.

Reported by Kavindu Santhusa.
See :issue:`1712`.
- Remove the ``__dict__`` attribute from `gevent.socket.socket` objects. The
standard library socket do not have a ``__dict__``.

Noticed by Carson Ip.

As part of this refactoring, share more common socket code between Python 2
and Python 3.
See :issue:`1724`.

----

20.9.0

===================


Features
--------

- The embedded libev is now asked to detect the availability of
``clock_gettime`` and use the realtime and/or monotonic clocks, if
they are available.

On Linux, this can reduce the number of system calls libev makes.
Originally provided by Josh Snyder.
See :issue:`1648`.


Bugfixes
--------

- On CPython, depend on greenlet >= 0.4.17. This version is binary
incompatible with earlier releases on CPython 3.7 and later.

On Python 3.7 and above, the module ``gevent.contextvars`` is no
longer monkey-patched into the standard library. contextvars are now
both greenlet and asyncio task local. See :issue:`1656`.
See :issue:`1674`.
- The ``DummyThread`` objects created automatically by certain
operations when the standard library threading module is
monkey-patched now match the naming convention the standard library
uses ("Dummy-12345"). Previously (since gevent 1.2a2) they used
"DummyThread-12345".
See :issue:`1659`.
- Fix compatibility with dnspython 2.

.. caution:: This currently means that it can be imported. But it
            cannot yet be used. gevent has a pinned dependency on
            dnspython < 2 for now.

See :issue:`1661`.


----

20.6.2

===================


Features
--------

- It is now possible to build and use the embedded libuv on a Cygwin
platform.

Note that Cygwin is not an officially supported platform of upstream
libuv and is not tested by gevent, so the actual working status is
unknown, and this may bitrot in future releases.

Thanks to berkakinci for the patch.
See :issue:`1645`.


Bugfixes
--------

- Relax the version constraint for psutil on PyPy.

Previously it was pinned to 5.6.3 for PyPy2, except for on Windows,
where it was excluded. It is now treated the same as CPython again.
See :issue:`1643`.


----

20.6.1

===================


Features
--------

- gevent's CI is now tested on Ubuntu 18.04 (Bionic), an upgrade from
16.04 (Xenial).
See :issue:`1623`.


Bugfixes
--------

- On Python 2, the dnspython resolver can be used without having
selectors2 installed. Previously, an ImportError would be raised.
See :issue:`1641`.
- Python 3 ``gevent.ssl.SSLSocket`` objects no longer attempt to catch
``ConnectionResetError`` and treat it the same as an ``SSLError`` with
``SSL_ERROR_EOF`` (typically by suppressing it).

This was a difference from the way the standard library behaved (which
is to raise the exception). It was added to gevent during early
testing of OpenSSL 1.1 and TLS 1.3.
See :issue:`1637`.


----

20.6.0

===================


Features
--------

- Add ``gevent.selectors`` containing ``GeventSelector``. This selector
implementation uses gevent details to attempt to reduce overhead when
polling many file descriptors, only some of which become ready at any
given time.

This is monkey-patched as ``selectors.DefaultSelector`` by default.

This is available on Python 2 if the ``selectors2`` backport is
installed. (This backport is installed automatically using the
``recommended`` extra.) When monkey-patching, ``selectors`` is made
available as an alias to this module.
See :issue:`1532`.
- Depend on greenlet >= 0.4.16. This is required for CPython 3.9 and 3.10a0.
See :issue:`1627`.
- Add support for Python 3.9.

No binary wheels are available yet, however.
See :issue:`1628`.


Bugfixes
--------

- ``gevent.socket.create_connection`` and
``gevent.socket.socket.connect`` no longer ignore IPv6 scope IDs.

Any IP address (IPv4 or IPv6) is no longer subject to an extra call to
``getaddrinfo``. Depending on the resolver in use, this is likely to
change the number and order of greenlet switches. (On Windows, in
particular test cases when there are no other greenlets running, it has
been observed to lead to ``LoopExit`` in scenarios that didn't produce
that before.)
See :issue:`1634`.


----

20.5.2

===================


Bugfixes
--------

- Forking a process that had use the threadpool to run tasks that
created their own hub would fail to clean up the threadpool by raising
``greenlet.error``.
See :issue:`1631`.


----

20.5.1

===================


Features
--------

- Waiters on Event and Semaphore objects that call ``wait()`` or
``acquire()``, respectively, that find the Event already set, or the
Semaphore available, no longer "cut in line" and run before any
previously scheduled greenlets. They now run in the order in which
they arrived, just as waiters that had to block in those methods do.
See :issue:`1520`.
- Update tested PyPy version from 7.3.0 to 7.3.1 on Linux.
See :issue:`1569`.
- Make ``zope.interface``, ``zope.event`` and (by extension)
``setuptools`` required dependencies. The ``events`` install extra now
does nothing and will be removed in 2021.
See :issue:`1619`.
- Update bundled libuv from 1.36.0 to 1.38.0.
See :issue:`1621`.
- Update bundled c-ares from 1.16.0 to 1.16.1.

On macOS, stop trying to adjust c-ares headers to make them
universal.
See :issue:`1624`.


Bugfixes
--------

- Make gevent locks that are monkey-patched usually work across native
threads as well as across greenlets within a single thread. Locks that
are only used in a single thread do not take a performance hit. While
cross-thread locking is relatively expensive, and not a recommended
programming pattern, it can happen unwittingly, for example when
using the threadpool and ``logging``.

Before, cross-thread lock uses might succeed, or, if the lock was
contended, raise ``greenlet.error``. Now, in the contended case, if
the lock has been acquired by the main thread at least once, it should
correctly block in any thread, cooperating with the event loop of both
threads. In certain (hopefully rare) cases, it might be possible for
contended case to raise ``LoopExit`` when previously it would have
raised ``greenlet.error``; if these cases are a practical concern,
please open an issue.

Also, the underlying Semaphore always behaves in an atomic fashion (as
if the GIL was not released) when PURE_PYTHON is set. Previously, it
only correctly did so on PyPy.
See :issue:`1437`.
- Rename gevent's C accelerator extension modules using a prefix to
avoid clashing with other C extensions.
See :issue:`1480`.
- Using ``gevent.wait`` on an ``Event`` more than once, when that Event
is already set, could previously raise an AssertionError.

As part of this, exceptions raised in the main greenlet will now
include a more complete traceback from the failing greenlet.
See :issue:`1540`.
- Avoid closing the same Python libuv watcher IO object twice. Under
some circumstances (only seen on Windows), that could lead to program
crashes.
See :issue:`1587`.
- gevent can now be built using Cython 3.0a5 and newer. The PyPI
distribution uses this version.

The libev extension was incompatible with this. As part of this,
certain internal, undocumented names have been changed.

(Technically, gevent can be built with Cython 3.0a2 and above.
However, up through 3.0a4 compiling with Cython 3 results in
gevent's test for memory leaks failing. See `this Cython issue
<https://github.com/cython/cython/issues/3578>`_.)
See :issue:`1599`.
- Destroying a hub after joining it didn't necessarily clean up all
resources associated with the hub, especially if the hub had been
created in a secondary thread that was exiting. The hub and its parent
greenlet could be kept alive.

Now, destroying a hub drops the reference to the hub and ensures it
cannot be switched to again. (Though using a new blocking API call may
still create a new hub.)

Joining a hub also cleans up some (small) memory resources that might
have stuck around for longer before as well.
See :issue:`1601`.
- Fix some potential crashes under libuv when using
``gevent.signal_handler``. The crashes were seen running the test
suite and were non-deterministic.
See :issue:`1606`.


----

20.5.0

===================


Features
--------

- Update bundled c-ares to version 1.16.0. `Changes <https://c-ares.haxx.se/changelog.html>`_.
See :issue:`1588`.
- Update all the bundled ``config.guess`` and ``config.sub`` scripts.
See :issue:`1589`.
- Update bundled libuv from 1.34.0 to 1.36.0.
See :issue:`1597`.


Bugfixes
--------

- Use ``ares_getaddrinfo`` instead of a manual lookup.

This requires c-ares 1.16.0.

Note that this may change the results, in particular their order.

As part of this, certain parts of the c-ares extension were adapted to
use modern Cython idioms.

A few minor errors and discrepancies were fixed as well, such as
``gethostbyaddr('localhost')`` working on Python 3 and failing on
Python 2. The DNSpython resolver now raises the expected TypeError in
more cases instead of an AttributeError.
See :issue:`1012`.
- The c-ares and DNSPython resolvers now raise exceptions much more
consistently with the standard resolver. Types and errnos are
substantially more likely to match what the standard library produces.

Depending on the system and configuration, results may not match
exactly, at least with DNSPython. There are still some rare cases
where the system resolver can raise ``herror`` but DNSPython will
raise ``gaierror`` or vice versa. There doesn't seem to be a
deterministic way to account for this. On PyPy, ``getnameinfo`` can
produce results when CPython raises ``socket.error``, and gevent's
DNSPython resolver also raises ``socket.error``.

In addition, several other small discrepancies were addressed,
including handling of localhost and broadcast host names.

.. note:: This has been tested on Linux (CentOS and Ubuntu), macOS,
         and Windows. It hasn't been tested on other platforms, so
         results are unknown for them. The c-ares support, in
         particular, is using some additional socket functions and
         defines. Please let the maintainers know if this introduces
         issues.

See :issue:`1459`.


----

20.04.0

====================


Features
--------

- Let CI (Travis and Appveyor) build and upload release wheels for
Windows, macOS and manylinux. As part of this, (a subset of) gevent's
tests can run if the standard library's ``test.support`` module has
been stripped.
See :issue:`1555`.
- Update tested PyPy version from 7.2.0 on Windows to 7.3.1.
See :issue:`1569`.


Bugfixes
--------

- Fix a spurious warning about watchers and resource leaks on libuv on
Windows. Reported by Stéphane Rainville.
See :issue:`1564`.
- Make monkey-patching properly remove ``select.epoll`` and
``select.kqueue``. Reported by Kirill Smelkov.
See :issue:`1570`.
- Make it possible to monkey-patch :mod:`contextvars` before Python 3.7
if a non-standard backport that uses the same name as the standard
library does is installed. Previously this would raise an error.
Reported by Simon Davy.
See :issue:`1572`.
- Fix destroying the libuv default loop and then using the default loop
again.
See :issue:`1580`.
- libuv loops that have watched children can now exit. Previously, the
SIGCHLD watcher kept the loop alive even if there were no longer any
watched children.
See :issue:`1581`.


Deprecations and Removals
-------------------------

- PyPy no longer uses the Python allocation functions for libuv and
libev allocations.
See :issue:`1569`.


Misc
----

- See :issue:`1367`.

Links

• PyPI: https://pypi.org/project/gevent
• Changelog: https://data.safetycli.com/changelogs/gevent/
• Homepage: http://www.gevent.org/

[pyup-bot]

Closing this in favor of #2913