Only set filename to cwd if it was caused by failed chdir(cwd).
_fork_exec() now returns "noexec:chdir" for failed chdir(cwd).
Co-authored-by: Robert O'Shea <PurityLake@users.noreply.github.com>
This comment appears to have been mistakenly copied from what is now
called iobase_check_closed() in commit 4d9aec0220.
Also unite the iobase_check_closed() code with the relevant comment.
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
If *trackfd* is False, the file descriptor specified by *fileno*
will not be duplicated.
Co-authored-by: Erlend E. Aasland <erlend@python.org>
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
On Windows, set _O_NOINHERIT flag on file descriptors
created by os.pipe() and io.WindowsConsoleIO.
Add test_pipe_spawnl() to test_os.
Co-authored-by: Zackery Spytz <zspytz@gmail.com>
Previously the C implementation of pickle.Pickler and pickle.Unpickler
classes did not have such methods and they could only be used if
they were overloaded in subclasses or set as instance attributes.
Fixed calling super().persistent_id() and super().persistent_load() in
subclasses of the C implementation of pickle.Pickler and pickle.Unpickler
classes. It no longer causes an infinite recursion.
When an `StopIteration` raises into `asyncio.Future`, this will cause
a thread to hang. This commit address this by not raising an exception
and silently transforming the `StopIteration` with a `RuntimeError`,
which the caller can reconstruct from `fut.exception().__cause__`
Remove LibreSSL specific workaround ifdefs from `_ssl.c` and delete the non-version-specific `_ssl_data.h` file (relevant for OpenSSL < 1.1.1, which we no longer support per PEP 644).
Co-authored-by: Christian Heimes <christian@python.org>
Co-authored-by: Gregory P. Smith <greg@krypto.org>
gh-113750: Fix object resurrection on free-threaded builds
This avoids the undesired re-initializing of fields like `ob_gc_bits`,
`ob_mutex`, and `ob_tid` when an object is resurrected due to its
finalizer being called.
This change has no effect on the default (with GIL) build.
This splits part of Modules/gcmodule.c of into Python/gc.c, which
now contains the core garbage collection implementation. The Python
module remain in the Modules/gcmodule.c file.
* gh-113536: Expose `os.waitid` on macOS
This API has been available on macOS for a long time, but was
explicitly excluded due to unspecified problems with the API
in ancient versions of macOS.
* Document that the API is available on macOS starting in Python 3.13
The length field of StgDictObject for Structure class contains now
the total number of items in ffi_type_pointer.elements (excluding
the trailing null).
The old behavior of using the number of elements in the parent class can
cause the array to be truncated when it is copied, especially when there
are multiple layers of subclassing.
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
First fix resolve situation when pyexpat module (which contains expat_CAPI
capsule) deallocates before _elementtree, so we need to hold a strong
reference to pyexpat module to.
Second fix resolve situation when module state is deallocated before
deallocation of XMLParser instances, which uses module state to clear
some stuff.
Add support for `os.POSIX_SPAWN_CLOSEFROM` and
`posix_spawn_file_actions_addclosefrom_np` and have the `subprocess` module use
them when available. This means `posix_spawn` can now be used in the default
`close_fds=True` situation on many platforms.
Co-authored-by: Gregory P. Smith [Google LLC] <greg@krypto.org>
* Allow posix_spawn to inherit environment form parent environ variable.
With this change, posix_spawn call can behave similarly to execv with regards to environments when used in subprocess functions.
The `PyThreadState_Clear()` function must only be called with the GIL
held and must be called from the same interpreter as the passed in
thread state. Otherwise, any Python objects on the thread state may be
destroyed using the wrong interpreter, leading to memory corruption.
This is also important for `Py_GIL_DISABLED` builds because free lists
will be associated with PyThreadStates and cleared in
`PyThreadState_Clear()`.
This fixes two places that called `PyThreadState_Clear()` from the wrong
interpreter and adds an assertion to `PyThreadState_Clear()`.
* bpo-43120: Add a number of LOG_* constants to syslog
This adds a number of syslog facilities to the syslogmodule.c.
These values are available on macOS.
* Switch contant documentation to the data directive
This fixes a CI warning and matches the pattern
used in the documentation for ``os``.
* Update Doc/library/syslog.rst
Co-authored-by: Hugo van Kemenade <hugovk@users.noreply.github.com>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
* gh-112529: Use atomic operations for `gcstate->collecting`
The `collecting` field in `GCState` is used to prevent overlapping garbage
collections within the same interpreter. This is updated to use atomic
operations in order to be thread-safe in `--disable-gil` builds.
The GC code is refactored a bit to support this. More of the logic is pushed
down to `gc_collect_main()` so that we can safely order the logic setting
`collecting`, the selection of the generation, and the invocation of callbacks
with respect to the atomic operations and the (future) stop-the-world pauses.
The change uses atomic operations for both `--disable-gil` and the default
build (with the GIL) to avoid extra `#ifdef` guards and ease the maintenance
burden.
* gh-51944: Add some macOS constants to termios
This changeset adds all public constants in <termio.h>
and <sys/termios.h> on macOS that weren't present
already.
Based on the macOS 14.2 SDK
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
* Implement _Py_HashPointerRaw() as a static inline function.
* Add Py_HashPointer() tests to test_capi.test_hash.
* Keep _Py_HashPointer() function as an alias to Py_HashPointer().
Set MAX_STRUCT_SIZE to 32 in stgdict.c when on Arm platforms.
This because on Arm platforms structs with at most 4 elements of any
floating point type values can be passed through registers. If the type
is double the maximum size of the struct is 32 bytes.
On x86-64 Linux, it's maximum 16 bytes hence we need to differentiate.
Restore `subprocess`'s intended use of `vfork()` by default for performance on Linux;
also fixes the behavior of `extra_groups=[]` which was unintentionally broken in 3.12.0:
Fixed a performance regression in 3.12's :mod:`subprocess` on Linux where it
would no longer use the fast-path ``vfork()`` system call when it could have
due to a logic bug, instead falling back to the safe but slower ``fork()``.
Also fixed a security bug introduced in 3.12.0. If a value of ``extra_groups=[]``
was passed to :mod:`subprocess.Popen` or related APIs, the underlying
``setgroups(0, NULL)`` system call to clear the groups list would not be made
in the child process prior to ``exec()``.
The security issue was identified via code inspection in the process of
fixing the first bug. Thanks to @vain for the detailed report and
analysis in the initial bug on Github.
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Work around a macOS bug, limit zlib crc32 calls to 1GiB.
Without this, `zlib.crc32` and `binascii.crc32` could produce incorrect
results on multi-gigabyte inputs depending on the macOS version's Apple
supplied zlib implementation.
Use a fraction internally in the _PyTime API to reduce the risk of
integer overflow: simplify the fraction using Greatest Common
Divisor (GCD). The fraction API is used by time functions:
perf_counter(), monotonic() and process_time().
For example, QueryPerformanceFrequency() usually returns 10 MHz on
Windows 10 and newer. The fraction SEC_TO_NS / frequency =
1_000_000_000 / 10_000_000 can be simplified to 100 / 1.
* Add _PyTimeFraction type.
* Add functions:
* _PyTimeFraction_Set()
* _PyTimeFraction_Mul()
* _PyTimeFraction_Resolution()
* No longer check "numer * denom <= _PyTime_MAX" in
_PyTimeFraction_Set(). _PyTimeFraction_Mul() uses _PyTime_Mul()
which handles integer overflow.
* Move _PyRuntimeState.time to _posixstate.ticks_per_second and
time_module_state.ticks_per_second.
* Add time_module_state.clocks_per_second.
* Rename _PyTime_GetClockWithInfo() to py_clock().
* Rename _PyTime_GetProcessTimeWithInfo() to py_process_time().
* Add process_time_times() helper function, called by
py_process_time().
* os.times() is now always built: no longer rely on HAVE_TIMES.
If OpenSSL was built without PSK support, the python TLS-PSK
methods will raise "NotImplementedError" if called.
Add a constant "ssl.HAS_PSK" to check if TLS-PSK is supported
Prevents a segmentation fault in registered hooks for the readline library, but only when the readline module is loaded inside an isolated sub interpreter. The module is single-phase init so loading it fails, but not until the module init function has already run, where the readline hooks get registered.
The readlinestate_global macro was error-prone to PyImport_FindModule returning NULL and crashing in about 18 places. I could reproduce 1 easily, but this PR replaces the macro with a function and adds error conditions to the other functions.
Add support for TLS-PSK (pre-shared key) to the ssl module.
---------
Co-authored-by: Oleg Iarygin <oleg@arhadthedev.net>
Co-authored-by: Gregory P. Smith <greg@krypto.org>
Revert commit c8c0afc713 (PR #94532),
which moved `struct.Struct` initialisation from `Struct.__init__` to `Struct.__new__`.
This caused issues with code in the wild that subclasses `struct.Struct`.
* Run again test_ast_recursion_limit() on WASI platform.
* Add _testinternalcapi.get_c_recursion_remaining().
* Fix test_ast and test_sys_settrace: test_ast_recursion_limit() and
test_trace_unpack_long_sequence() now adjust the maximum recursion
depth depending on the the remaining C recursion.
This avoids:
python3.13 Tools/unicode/makeunicodedata.py
python3.13: can't open file '.../build/debug/Tools/unicode/makeunicodedata.py': [Errno 2] No such file or directory
make: *** [Makefile:1498: regen-unicodedata] Error 2
Re-run `make regen-unicodedata` to update the script path in generated files.
In non-debug more the check for the "errors" argument is skipped,
and then PyUnicode_AsUTF8() can fail, but its result was not checked.
Co-authored-by: Victor Stinner <vstinner@python.org>
* Fix crash when encoding is not string or None.
* Fix crash when both line_buffering and write_through raise exception
when converted ti int.
* Add a number of tests for constructor and reconfigure() method
with invalid arguments.
_PyDict_Pop_KnownHash(): remove the default value and the return type
becomes an int.
Co-authored-by: Stefan Behnel <stefan_ml@behnel.de>
Co-authored-by: Antoine Pitrou <pitrou@free.fr>
The `@critical_section` directive instructs Argument Clinic to generate calls
to `Py_BEGIN_CRITICAL_SECTION()` and `Py_END_CRITICAL_SECTION()` around the
bound function. In `--disable-gil` builds, these calls will lock and unlock
the `self` object. They are no-ops in the default build.
This is used in one place (`_io._Buffered.close`) as a demonstration.
Subsequent PRs will use it more widely in the `_io.Buffered` bindings.
* Split list_extend() into two sub-functions: list_extend_fast() and
list_extend_iter().
* list_inplace_concat() no longer has to call Py_DECREF() on the
list_extend() result, since list_extend() now returns an int.
In PyObject_GC_Del, in Py_DEBUG mode, when warning about GC objects that
were not properly untracked before starting destruction, take care to
untrack the object _before_ warning, to avoid triggering a GC run and
causing the problem the code tries to warn about. Also make sure to save and
restore any pending exceptions, which the warning would otherwise clobber or
trigger an assertion error on.
Fix undefined behaviour in datetime.time.fromisoformat() when parsing a string without a timezone. 'tzoffset' is not assigned to by parse_isoformat_time if it returns 0, but time_fromisoformat then passes tzoffset to another function, which is undefined behaviour (even if the function in question does not use the value).
This adds a macro `Py_CAN_START_THREADS` that corresponds to the Python
function `test.support.threading_helper.can_start_thread()`. WASI and
some Emscripten builds do not have a working pthread implementation.
This macro is used to guard the critical sections C API tests that
require a working threads implementation.
Drop posix.fallocate() under WASI.
The underlying POSIX function, posix_fallocate(), was found to vary too
much between implementations to remain in WASI. As such, while it was
available in WASI preview1, it's been dropped in preview2.
Critical sections are helpers to replace the global interpreter lock
with finer grained locking. They provide similar guarantees to the GIL
and avoid the deadlock risk that plain locking involves. Critical
sections are implicitly ended whenever the GIL would be released. They
are resumed when the GIL would be acquired. Nested critical sections
behave as if the sections were interleaved.
* Revert "gh-111089: Use PyUnicode_AsUTF8() in Argument Clinic (#111585)"
This reverts commit d9b606b3d0.
* Revert "gh-111089: Use PyUnicode_AsUTF8() in getargs.c (#111620)"
This reverts commit cde1071b2a.
* Revert "gh-111089: PyUnicode_AsUTF8() now raises on embedded NUL (#111091)"
This reverts commit d731579bfb.
* Revert "gh-111089: Add PyUnicode_AsUTF8() to the limited C API (#111121)"
This reverts commit d8f32be5b6.
* Revert "gh-111089: Use PyUnicode_AsUTF8() in sqlite3 (#111122)"
This reverts commit 37e4e20eaa.
Joining a thread now ensures the underlying OS thread has exited. This is required for safer fork() in multi-threaded processes.
---------
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Use Argument Clinic for time.clock_gettime() and
time.clock_gettime_ns() functions.
Benchmark on time.clock_gettime_ns():
import time
import pyperf
runner = pyperf.Runner()
runner.timeit(
'clock_gettime_ns(CLOCK_MONOTONIC_COARSE)',
setup='import time; clock_gettime_ns=time.clock_gettime_ns; CLOCK_MONOTONIC_COARSE=6',
stmt='clock_gettime_ns(CLOCK_MONOTONIC_COARSE)')
Result on Linux with CPU isolation:
Mean +- std dev: [ref] 134 ns +- 1 ns -> [change] 55.7 ns +- 1.4 ns: 2.41x faster
Replace most of calls of _PyErr_WriteUnraisableMsg() and some
calls of PyErr_WriteUnraisable(NULL) with PyErr_FormatUnraisable().
Co-authored-by: Victor Stinner <vstinner@python.org>
This moves several general internal APIs out of _xxsubinterpretersmodule.c and into the new Python/crossinterp.c (and the corresponding internal headers).
Specifically:
* _Py_excinfo, etc.: the initial implementation for non-object exception snapshots (in pycore_pyerrors.h and Python/errors.c)
* _PyXI_exception_info, etc.: helpers for passing an exception beween interpreters (wraps _Py_excinfo)
* _PyXI_namespace, etc.: helpers for copying a dict of attrs between interpreters
* _PyXI_Enter(), _PyXI_Exit(): functions that abstract out the transitions between one interpreter and a second that will do some work temporarily
Again, these were all abstracted out of _xxsubinterpretersmodule.c as generalizations. I plan on proposing these as public API at some point.
Replace PyUnicode_AsUTF8AndSize() with PyUnicode_AsUTF8() to remove
the explicit check for embedded null characters.
The change avoids to have to include explicitly <string.h> to get the
strlen() function when using a recent version of the limited C API.
This is partly to clear this stuff out of pystate.c, but also in preparation for moving some code out of _xxsubinterpretersmodule.c. This change also moves this stuff to the internal API (new: Include/internal/pycore_crossinterp.h). @vstinner did this previously and I undid it. Now I'm re-doing it. :/
* Add mimalloc v2.12
Modified src/alloc.c to remove include of alloc-override.c and not
compile new handler.
Did not include the following files:
- include/mimalloc-new-delete.h
- include/mimalloc-override.h
- src/alloc-override-osx.c
- src/alloc-override.c
- src/static.c
- src/region.c
mimalloc is thread safe and shares a single heap across all runtimes,
therefore finalization and getting global allocated blocks across all
runtimes is different.
* mimalloc: minimal changes for use in Python:
- remove debug spam for freeing large allocations
- use same bytes (0xDD) for freed allocations in CPython and mimalloc
This is important for the test_capi debug memory tests
* Don't export mimalloc symbol in libpython.
* Enable mimalloc as Python allocator option.
* Add mimalloc MIT license.
* Log mimalloc in Lib/test/pythoninfo.py.
* Document new mimalloc support.
* Use macro defs for exports as done in:
https://github.com/python/cpython/pull/31164/
Co-authored-by: Sam Gross <colesbury@gmail.com>
Co-authored-by: Christian Heimes <christian@python.org>
Co-authored-by: Victor Stinner <vstinner@python.org>
* gh-106320: Re-add _PyLong_FromByteArray(), _PyLong_AsByteArray() and _PyLong_GCD() to the public header files since they are used by third-party packages and there is no efficient replacement.
See https://github.com/python/cpython/issues/111140
See https://github.com/python/cpython/issues/111139
* gh-111262: Re-add _PyDict_Pop() to have a C-API until a new public one is designed.
* Move existing tests for PySys_GetObject() and PySys_SetObject() into
specialized files.
* Add test for PySys_GetXOptions() using _testcapi.
* Add tests for PySys_FormatStdout(), PySys_FormatStderr(),
PySys_WriteStdout() and PySys_WriteStderr() using ctypes.
Add PyUnicode_AsUTF8() function to the limited C API.
multiprocessing posixshmem now uses PyUnicode_AsUTF8() instead of
PyUnicode_AsUTF8AndSize(): the extension is built with the limited C
API. The function now raises an exception if the filename contains an
embedded null character instead of truncating silently the filename.
Build the _multiprocessing.posixshmem extension with the Limited C
API.
* Add <errno.h> include.
* Replace PyUnicode_AsUTF8() with PyUnicode_AsUTF8AndSize().
There were a few things I did in gh-110565 that need to be fixed. I also forgot to add tests in that PR.
(Note that this PR exposes a refleak introduced by gh-110246. I'll take care of that separately.)
* Replace PyStructSequence_SET_ITEM() with
PyStructSequence_SetItem().
* Replace PyTuple_GET_SIZE() with PyTuple_Size().
* Replace PyTuple_GET_ITEM() with PyTuple_GetItem().
Move the following private functions and structures to
pycore_modsupport.h internal C API:
* _PyArg_BadArgument()
* _PyArg_CheckPositional()
* _PyArg_NoKeywords()
* _PyArg_NoPositional()
* _PyArg_ParseStack()
* _PyArg_ParseStackAndKeywords()
* _PyArg_Parser structure
* _PyArg_UnpackKeywords()
* _PyArg_UnpackKeywordsWithVararg()
* _PyArg_UnpackStack()
* _Py_ANY_VARARGS()
Changes:
* Python/getargs.h now includes pycore_modsupport.h to export
functions.
* clinic.py now adds pycore_modsupport.h when one of these functions
is used.
* Add pycore_modsupport.h includes when a C extension uses one of
these functions.
* Define Py_BUILD_CORE_MODULE in C extensions which now include
directly or indirectly (via code generated by Argument Clinic)
pycore_modsupport.h:
* _csv
* _curses_panel
* _dbm
* _gdbm
* _multiprocessing.posixshmem
* _sqlite.row
* _statistics
* grp
* resource
* syslog
* _testcapi: bad_get() no longer uses METH_FASTCALL calling
convention but METH_VARARGS. Replace _PyArg_UnpackStack() with
PyArg_ParseTuple().
* _testcapi: add PYTESTCAPI_NEED_INTERNAL_API macro which is defined
by _testcapi sub-modules which need the internal C API
(pycore_modsupport.h): exceptions.c, float.c, vectorcall.c,
watchers.c.
* Remove Include/cpython/modsupport.h header file.
Include/modsupport.h no longer includes the removed header file.
* Fix mypy clinic.py
* Only add Py_MOD_PER_INTERPRETER_GIL_SUPPORTED to limited C API
version 3.13.
* errno, xxlimited and _ctypes_test extensions now need the limited C
API version 3.13 to get Py_MOD_PER_INTERPRETER_GIL_SUPPORTED. They
now include standard header files explicitly: <errno.h>, <string.h>
and <stdio.h>.
* xxlimited_35: Remove Py_mod_multiple_interpreters slot,
incompatible with limited C API version 3.5.
zipinfo now supports the full range of values in the TZ string
determined by RFC 8536 and detects all invalid formats.
Both Python and C implementations now raise exceptions of the same
type on invalid data.
Now re.error is raised instead of OverflowError or RuntimeError for
too large width of look-behind pattern.
The limit is increased to 2**32-1 (was 2**31-1).
* Use explicit initialiser for m_base
* Add module state stub; establish global state on stack
* Put conversion factors in state struct
* Move PyDateTime_TimeZone_UTC to state
* Move PyDateTime_Epoch to state struct
* Fix ref leaks in and clean up initialisation
Add wrapper for timerfd_create, timerfd_settime, and timerfd_gettime to os module.
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>
Co-authored-by: Victor Stinner <vstinner@python.org>
* Use `FindFirstFile` Win32 API to fix a bug where `ntpath.realpath()`
breaks out of traversing a series of paths where a (handled)
`ERROR_ACCESS_DENIED` or `ERROR_SHARING_VIOLATION` occurs.
* Update docs to reflect that `ntpath.realpath()` eliminates MS-DOS
style names.
This is a temporary solution. The full fix may involve serializing the traceback in some form.
(FYI, I merged this yesterday and the reverted it due to buildbot failures. See gh-110248.)
Add PyThreadState_GetUnchecked() function: similar to
PyThreadState_Get(), but don't issue a fatal error if it is NULL. The
caller is responsible to check if the result is NULL. Previously,
this function was private and known as _PyThreadState_UncheckedGet().
In a few places we switch to another interpreter without knowing if it has a thread state associated with the current thread. For the main interpreter there wasn't much of a problem, but for subinterpreters we were *mostly* okay re-using the tstate created with the interpreter (located via PyInterpreterState_ThreadHead()). There was a good chance that tstate wasn't actually in use by another thread.
However, there are no guarantees of that. Furthermore, re-using an already used tstate is currently fragile. To address this, now we create a new thread state in each of those places and use it.
One consequence of this change is that PyInterpreterState_ThreadHead() may not return NULL (though that won't happen for the main interpreter).
The existence of background threads running on a subinterpreter was preventing interpreters from getting properly destroyed, as well as impacting the ability to run the interpreter again. It also affected how we wait for non-daemon threads to finish.
We add PyInterpreterState.threads.main, with some internal C-API functions.
This change makes sure sys.path[0] is set properly for subinterpreters. Before, it wasn't getting set at all. This PR does not address the broader concerns from gh-109853.
Make PyObject_VisitManagedDict() and PyObject_ClearManagedDict()
functions public in Python 3.13 C API.
* Rename _PyObject_VisitManagedDict() to PyObject_VisitManagedDict().
* Rename _PyObject_ClearManagedDict() to PyObject_ClearManagedDict().
* Document these functions.
* Refactor os_sched_getaffinity_impl(): move variable definitions to
their first assignment.
* Fix test_posix.test_sched_getaffinity(): restore the old CPU mask
when the test completes!
* Doc: Specify that os.cpu_count() counts *logicial* CPUs.
* Doc: Specify that os.sched_getaffinity(0) is related to the calling
thread.
* Remove unused <locale.h> includes.
* Remove unused <fcntl.h> include in traceback.h.
* Remove redundant <assert.h> and <stddef.h> includes. They are already
included by "Python.h".
* Remove <object.h> include in faulthandler.c. Python.h already includes it.
* Add missing <stdbool.h> in pycore_pythread.h if HAVE_PTHREAD_STUBS
is defined.
* Fix also warnings in pthread_stubs.h: don't redefine macros if they
are already defined, like the __NEED_pthread_t macro.
Make sure that the internal C API is not tested by mistake by
_testcapi.
Undefine Py_BUILD_CORE_BUILTIN and Py_BUILD_CORE_MODULE macros in
Modules/_testcapi/parts.h: move code from _testcapimodule.c.
heaptype_relative.c and vectorcall_limited.c are using the limited C
API which is incompatible with the internal C API.
Move test_long_numbits() from _testcapi to _testinternalcapi since it
uses the internal C API "pycore_long.h".
Fix Modules/_testcapi/pyatomic.c: don't include Python.h directly,
just include _testcapi/parts.h.
Ajust "make check-c-globals" for these changes.
Fix os.stat() and os.DirEntry.stat(): check for exceptions.
Previously, on Python built in debug mode, these functions could
trigger a fatal Python error (and abort the process) when a function
succeeded with an exception set.
_pystat_fromstructstat() now exits immediately if an exception is
raised, rather only checking for exceptions at the end. It fix
following fatal error in fill_time():
Fatal Python error: _Py_CheckSlotResult:
Slot * of type int succeeded with an exception set
The filename was previously intentionally omitted from exception because
"it might confuse the user". Uncaught exceptions are not generally a
replacement for user-facing error messages, so obscuring this
information only has the effect of making the programmer's life more
difficult.
PyMutex is a one byte lock with fast, inlineable lock and unlock functions for the common uncontended case. The design is based on WebKit's WTF::Lock.
PyMutex is built using the _PyParkingLot APIs, which provides a cross-platform futex-like API (based on WebKit's WTF::ParkingLot). This internal API will be used for building other synchronization primitives used to implement PEP 703, such as one-time initialization and events.
This also includes tests and a mini benchmark in Tools/lockbench/lockbench.py to compare with the existing PyThread_type_lock.
Uncontended acquisition + release:
* Linux (x86-64): PyMutex: 11 ns, PyThread_type_lock: 44 ns
* macOS (arm64): PyMutex: 13 ns, PyThread_type_lock: 18 ns
* Windows (x86-64): PyMutex: 13 ns, PyThread_type_lock: 38 ns
PR Overview:
The primary purpose of this PR is to implement PyMutex, but there are a number of support pieces (described below).
* PyMutex: A 1-byte lock that doesn't require memory allocation to initialize and is generally faster than the existing PyThread_type_lock. The API is internal only for now.
* _PyParking_Lot: A futex-like API based on the API of the same name in WebKit. Used to implement PyMutex.
* _PyRawMutex: A word sized lock used to implement _PyParking_Lot.
* PyEvent: A one time event. This was used a bunch in the "nogil" fork and is useful for testing the PyMutex implementation, so I've included it as part of the PR.
* pycore_llist.h: Defines common operations on doubly-linked list. Not strictly necessary (could do the list operations manually), but they come up frequently in the "nogil" fork. ( Similar to https://man.freebsd.org/cgi/man.cgi?queue)
---------
Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>
On a Python built in debug mode, Py_DECREF() now calls
_Py_NegativeRefcount() if the object is a dangling pointer to
deallocated memory: memory filled with 0xDD "dead byte" by the debug
hook on memory allocators. The fix is to check the reference count
*before* checking for _Py_IsImmortal().
Add test_decref_freed_object() to test_capi.test_misc.
Builtin functions and methods that have non-representable signatures today
will have representable signatures yesterday, and they will become unusable
for testing this feature.
So we need to add special functions and methods to the _testcapi module
that always have non-representable signatures.
Fix _thread.start_new_thread() race condition. If a thread is created
during Python finalization, the newly spawned thread now exits
immediately instead of trying to access freed memory and lead to a
crash.
thread_run() calls PyEval_AcquireThread() which checks if the thread
must exit. The problem was that tstate was dereferenced earlier in
_PyThreadState_Bind() which leads to a crash most of the time.
Move _PyThreadState_CheckConsistency() from thread_run() to
_PyThreadState_Bind().
thread_run() of _threadmodule.c now calls
_PyThreadState_CheckConsistency() to check if tstate is a dangling
pointer when Python is built in debug mode.
Rename ceval_gil.c is_tstate_valid() to
_PyThreadState_CheckConsistency() to reuse it in _threadmodule.c.
Symbols of the C API should be prefixed by "Py_" to avoid conflict
with existing names in 3rd party C extensions on "#include <Python.h>".
test.pythoninfo now logs Py_C_RECURSION_LIMIT constant and other
_testcapi and _testinternalcapi constants.
Commit 13a00078b8 (#108663) made all
Python builds compatible with the Limited API, and removed the
LIMITED_API_AVAILABLE flag. However, some tests were still checking
for that flag, so they were now being incorrectly skipped. Remove
these checks to let these tests run again.
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
It creates a modified copy of an object by calling the object's
__replace__() method.
It is a generalization of dataclasses.replace(), named tuple's _replace()
method and replace() methods in various classes, and supports all these
stdlib classes.
Statistics gathering is now off by default. Use the "-X pystats"
command line option or set the new PYTHONSTATS environment variable
to 1 to turn statistics gathering on at Python startup.
Statistics are no longer dumped at exit if statistics gathering was
off or statistics have been cleared.
Changes:
* Add PYTHONSTATS environment variable.
* sys._stats_dump() now returns False if statistics are not dumped
because they are all equal to zero.
* Add PyConfig._pystats member.
* Add tests on sys functions and on setting PyConfig._pystats to 1.
* Add Include/cpython/pystats.h and Include/internal/pycore_pystats.h
header files.
* Rename '_py_stats' variable to '_Py_stats'.
* Exclude Include/cpython/pystats.h from the Py_LIMITED_API.
* Move pystats.h include from object.h to Python.h.
* Add _Py_StatsOn() and _Py_StatsOff() functions. Remove
'_py_stats_struct' variable from the API: make it static in
specialize.c.
* Document API in Include/pystats.h and Include/cpython/pystats.h.
* Complete pystats documentation in Doc/using/configure.rst.
* Don't write "all zeros" stats: if _stats_off() and _stats_clear()
or _stats_dump() were called.
* _PyEval_Fini() now always call _Py_PrintSpecializationStats() which
does nothing if stats are all zeros.
Co-authored-by: Michael Droettboom <mdboom@gmail.com>
Move the private _PyErr_WriteUnraisableMsg() functions to the
internal C API (pycore_pyerrors.h).
Move write_unraisable_exc() from _testcapi to _testinternalcapi.
Remove <ctype.h> in C files which don't use it; only sre.c and
_decimal.c still use it.
Remove _PY_PORT_CTYPE_UTF8_ISSUE code from pyport.h:
* Code added by commit b5047fd019
in 2004 for MacOSX and FreeBSD.
* Test removed by commit 52ddaefb6b
in 2007, since Python str type now uses locale independent
functions like Py_ISALPHA() and Py_TOLOWER() and the Unicode
database.
Modules/_sre/sre.c replaces _PY_PORT_CTYPE_UTF8_ISSUE with new
functions: sre_isalnum(), sre_tolower(), sre_toupper().
Remove unused includes:
* _localemodule.c: remove <stdio.h>.
* getargs.c: remove <float.h>.
* dynload_win.c: remove <direct.h>, it no longer calls _getcwd()
since commit fb1f68ed7c (in 2001).
- input checks for math_1(L989), math_1a(L1023), math_2(L1064,L1071), hypot(L2682), log(L2307), ldexp(L2168), ceil(L1165), floor(L1236,L1239) and dist(L2587,L2588,L2628).
- drop inaccessible "if" branch (L3518) in perm_comb_small()
- improve fsum coverage for exceptional cases (L1433,L1438,L1451,L1497), ditto fmod(L2378)
- rewrite modf to fix inaccessible case(L2229), ditto for pow(L2988)
(all line numbers are wrt the main branch at 5e6661bce9)