send_signal() now swallows the exception if the process it thought was still alive winds up not to exist anymore (always a plausible race condition despite the checks).
Co-authored-by: Gregory P. Smith <greg@krypto.org>
* bpo-40791: Make compare_digest more constant-time.
The existing volatile `left`/`right` pointers guarantee that the reads will all occur, but does not guarantee that they will be _used_. So a compiler can still short-circuit the loop, saving e.g. the overhead of doing the xors and especially the overhead of the data dependency between `result` and the reads. That would change performance depending on where the first unequal byte occurs. This change removes that optimization.
(This is change #1 from https://bugs.python.org/issue40791 .)
Added slice support to the `pathlib.Path.parents` sequence. For a `Path` `p`, slices of `p.parents` should return the same thing as slices of `tuple(p.parents)`.
Simplify the importlib external bootstrap code:
importlib._bootstrap_external now uses regular imports to import
builtin modules. When it is imported, the builtin __import__()
function is already fully working and so can be used to import
builtin modules like sys.
This change partically reverts
commit ad3252bad9
and the commit fe2978b3b9.
Many third party C extension modules rely on the ability of using
Py_TYPE() to set an object type: "Py_TYPE(obj) = type;" or to set an
object type using: "Py_SIZE(obj) = size;".
Fix a race condition in "make regen-all" when make -jN option is used
to run jobs in parallel. The clinic.py script now only use atomic
write to write files. Moveover, generated files are now left
unchanged if the content does not change, to not change the file
modification time.
The "make regen-all" command runs "make clinic" and "make
regen-importlib" targets:
* "make regen-importlib" builds object files (ex: Modules/_weakref.o)
from source files (ex: Modules/_weakref.c) and clinic files (ex:
Modules/clinic/_weakref.c.h)
* "make clinic" always rewrites all clinic files
(ex: Modules/clinic/_weakref.c.h)
Since there is no dependency between "clinic" and "regen-importlib"
Makefile targets, these two targets can be run in parallel. Moreover,
half of clinic.py file writes are not atomic and so there is a race
condition when "make regen-all" runs jobs in parallel using make -jN
option (which can be passed in MAKEFLAGS environment variable).
Fix clinic.py to make all file writes atomic:
* Add write_file() function to ensure that all file writes are
atomic: write into a temporary file and then use os.replace().
* Moreover, write_file() doesn't recreate or modify the file if the
content does not change to avoid modifying the file modification
file.
* Update test_clinic to verify these assertions with a functional
test.
* Remove Clinic.force attribute which was no longer used, whereas
Clinic.verify remains useful.
bpo-41686, bpo-41713: On Windows, the SIGINT event,
_PyOS_SigintEvent(), is now created even if Python is configured to
not install signal handlers (PyConfig.install_signal_handlers=0 or
Py_InitializeEx(0)).
Changes:
* Move global variables initialization from signal_exec() to
_PySignal_Init() to clarify that they are global variables cleared
by _PySignal_Fini().
* _PySignal_Fini() now closes sigint_event.
* IntHandler is no longer a global variable.
Remove the undocumented PyOS_InitInterrupts() C function.
* Rename PyOS_InitInterrupts() to _PySignal_Init(). It now installs
other signal handlers, not only SIGINT.
* Rename PyOS_FiniInterrupts() to _PySignal_Fini()
Literal equality no longer depends on the order of arguments.
Fix issue related to `typing.Literal` caching by adding `typed` parameter to `typing._tp_cache` function.
Add deduplication of `typing.Literal` arguments.
Currently walruses are not allowerd in set literals and set comprehensions:
>>> {y := 4, 4**2, 3**3}
File "<stdin>", line 1
{y := 4, 4**2, 3**3}
^
SyntaxError: invalid syntax
but they should be allowed as well per PEP 572
As AIX 5.3 and below do not support thread_cputime, it was decided in
https://bugs.python.org/issue40680 to require AIX 6.1 and above. This
commit removes workarounds for — and references to — older, unsupported
AIX versions.
time.time(), time.perf_counter() and time.monotonic() functions can
no longer fail with a Python fatal error, instead raise a regular
Python exception on failure.
Remove _PyTime_Init(): don't check system, monotonic and perf counter
clocks at startup anymore.
On error, _PyTime_GetSystemClock(), _PyTime_GetMonotonicClock() and
_PyTime_GetPerfCounter() now silently ignore the error and return 0.
They cannot fail with a Python fatal error anymore.
Add py_mach_timebase_info() and win_perf_counter_frequency()
sub-functions.
Fix the threading.Thread class at fork: do nothing if the thread is
already stopped (ex: fork called at Python exit). Previously, an
error was logged in the child process.
time.perf_counter() on Windows and time.monotonic() on macOS are now
system-wide. Previously, they used an offset computed at startup to
reduce the precision loss caused by the float type. Use
time.perf_counter_ns() and time.monotonic_ns() added in Python 3.7 to
avoid this precision loss.
Fix building pycore_bitutils.h internal header on old clang version
without __builtin_bswap16() (ex: Xcode 4.6.3 on Mac OS X 10.7).
Add a new private _Py__has_builtin() macro to check for availability
of a preprocessor builtin function.
Co-Authored-By: Joshua Root <jmr@macports.org>
Co-authored-by: Joshua Root <jmr@macports.org>
On Windows, fix a regression in signal handling which prevented to
interrupt a program using CTRL+C. The signal handler can be run in a
thread different than the Python thread, in which case the test
deciding if the thread can handle signals is wrong.
On Windows, _PyEval_SignalReceived() now always sets eval_breaker to
1 since it cannot test _Py_ThreadCanHandleSignals(), and
eval_frame_handle_pending() always calls
_Py_ThreadCanHandleSignals() to recompute eval_breaker.
It is no longer possible to build the _ctypes extension module
without wchar_t type: remove CTYPES_UNICODE macro. Anyway, the
wchar_t type is required to build Python.
# Improve asyncio.wait function
The original code creates the futures set two times.
We can create this set before, avoiding the second creation.
This new behaviour [breaks the aiokafka library](https://github.com/aio-libs/aiokafka/pull/672), because it gives an iterator to that function, so the second iteration become empty.
Automerge-Triggered-By: GH:1st1
Fix _PyConfig_Read() if compute_path_config=0: use values set by
Py_SetPath(), Py_SetPythonHome() and Py_SetProgramName(). Add
compute_path_config parameter to _PyConfig_InitPathConfig().
The following functions now return NULL if called before
Py_Initialize():
* Py_GetExecPrefix()
* Py_GetPath()
* Py_GetPrefix()
* Py_GetProgramFullPath()
* Py_GetProgramName()
* Py_GetPythonHome()
These functions no longer automatically computes the Python Path
Configuration. Moreover, Py_SetPath() no longer computes
program_full_path.
The onerror is supposed to be called with failed function, but in this case lstat is wrongly used instead of open.
Not sure if this needs bug or not...
Automerge-Triggered-By: GH:hynek
Adds support to Tools/i18n/pygettext.py for gettext calls in f-strings. This process is done by parsing the f-strings, processing each value, and flagging the ones which contain a gettext call.
Co-authored-by: Batuhan Taskaya <batuhanosmantaskaya@gmail.com>
Co-authored-by: Lawrence D’Anna <lawrence_danna@apple.com>
* Add support for macOS 11 and Apple Silicon (aka arm64)
As a side effect of this work use the system copy of libffi on macOS, and remove the vendored copy
* Support building on recent versions of macOS while deploying to older versions
This allows building installers on macOS 11 while still supporting macOS 10.9.
* The AST optimiser wasn't descending into named expressions, so
any constant subexpressions weren't being folded at compile time
* Remove "default:" clauses inside the AST optimiser code to reduce the
risk of similar bugs passing unnoticed in future compiler changes
The format_exception(), format_exception_only(), and
print_exception() functions can now take an exception object as a positional-only argument.
Co-Authored-By: Matthias Bussonnier <bussonniermatthias@gmail.com>
The PyConfig_Read() function now only parses PyConfig.argv arguments
once: PyConfig.parse_argv is set to 2 after arguments are parsed.
Since Python arguments are strippped from PyConfig.argv, parsing
arguments twice would parse the application options as Python
options.
* Rework the PyConfig documentation.
* Fix _testinternalcapi.set_config() error handling.
* SetConfigTests no longer needs parse_argv=0 when restoring the old
configuration.
Currently, a Mock object which is not unsafe will raise an
AttributeError if an attribute with the prefix assert or assret is
accessed on it. This protects against misspellings of real assert
method calls, which lead to tests passing silently even if the tested
code does not satisfy the intended assertion.
Recently a check was done in a large code base (Google) and three
more frequent ways of misspelling assert were found causing harm:
asert, aseert, assrt. These are now added to the existing check.
When Py_Initialize() is called twice, the second call now updates
more sys attributes for the configuration, rather than only sys.argv.
* Rename _PySys_InitMain() to _PySys_UpdateConfig().
* _PySys_UpdateConfig() now modifies sys.flags in-place, instead of
creating a new flags object.
* Remove old commented sys.flags flags (unbuffered and skip_first).
* Add private _PySys_GetObject() function.
* When Py_Initialize(), Py_InitializeFromConfig() and
The logging.FileHandler class now keeps a reference to the builtin
open() function to be able to open or reopen the file during Python
finalization.
Fix errors like:
Exception ignored in: (...)
Traceback (most recent call last):
(...)
File ".../logging/__init__.py", line 1463, in error
File ".../logging/__init__.py", line 1577, in _log
File ".../logging/__init__.py", line 1587, in handle
File ".../logging/__init__.py", line 1649, in callHandlers
File ".../logging/__init__.py", line 948, in handle
File ".../logging/__init__.py", line 1182, in emit
File ".../logging/__init__.py", line 1171, in _open
NameError: name 'open' is not defined
The ast module internal state is now per interpreter.
* Rename "astmodulestate" to "struct ast_state"
* Add pycore_ast.h internal header: the ast_state structure is now
declared in pycore_ast.h.
* Add PyInterpreterState.ast (struct ast_state)
* Remove get_ast_state()
* Rename get_global_ast_state() to get_ast_state()
* PyAST_obj2mod() now handles get_ast_state() failures
* Prevent some possible DoS attacks via providing invalid Plist files
with extremely large number of objects or collection sizes.
* Raise InvalidFileException for too large bytes and string size instead of returning garbage.
* Raise InvalidFileException instead of ValueError for specific invalid datetime (NaN).
* Raise InvalidFileException instead of TypeError for non-hashable dict keys.
* Add more tests for invalid Plist files.
This adds a new function named sys._current_exceptions() which is equivalent ot
sys._current_frames() except that it returns the exceptions currently handled
by other threads. It is equivalent to calling sys.exc_info() for each running
thread.
They were occurring with both repeated 'force-calltip' invocations and by typing parentheses
in expressions, strings, and comments in the argument code.
Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
* bpo-37193: remove the thread which finished process request from threads list
* rename variable t to thread.
* don't remove thread from list if it is daemon.
* use lock to protect self._threads.
* use finally block in case of exception from shutdown_request().
* check "not thread.daemon" before lock to avoid holding the lock if it's unnecessary.
* fix the place of _threads_lock.
* separate code to remove a current thread into a function.
* check ValueError when removing thread.
* fix wrong code which all instance shared same lock.
* Extract thread management into a _Threads class to encapsulate atomic operations and separate concerns.
* Replace multiple references of 'block_on_close' with one, avoiding the possibility that 'block_on_close' could change during the course of processing requests. Now, there's exactly one _threads object with behavior fixed for the duration.
* Add docstrings to private classes.
* Add test to ensure that a ThreadingTCPServer can be closed without serving any requests.
* Use _NoThreads as the default value. Fixes AttributeError when server is closed without serving any requests.
* Add blurb
* Add test capturing failure.
Co-authored-by: Jason R. Coombs <jaraco@jaraco.com>
If the nl_langinfo(CODESET) function returns an empty string, Python
now uses UTF-8 as the filesystem encoding.
In May 2010 (commit b744ba1d14), I
modified Python to log a warning and use UTF-8 as the filesystem
encoding (instead of None) if nl_langinfo(CODESET) returns an empty
string.
In August 2020 (commit 94908bbc15), I
modified Python startup to fail with a fatal error and a specific
error message if nl_langinfo(CODESET) returns an empty string. The
intent was to prevent guessing the encoding and also investigate user
configuration where this case happens.
In 10 years (2010 to 2020), I saw zero user report about the error
message related to nl_langinfo(CODESET) returning an empty string.
Today, UTF-8 became the defacto standard and it's safe to make the
assumption that the user expects UTF-8. For example,
nl_langinfo(CODESET) can return an empty string on macOS if the
LC_CTYPE locale is not supported, and UTF-8 is the default encoding
on macOS.
While this change is likely to not affect anyone in practice, it
should make UTF-8 lover happy ;-)
Rewrite also the documentation explaining how Python selects the
filesystem encoding and error handler.