Clang-cl detects that on 32-bit builds the variable is always smaller than the value. But since the same code is used for other architectures, we can't just _fix_ it. This cast avoids the tautological-constant-out-of-range-compare warning.
This fixes os.link() on platforms (like Linux and OpenIndiana) where the
system link() function does not follow symlinks.
* On Linux, it now follows symlinks by default and if
follow_symlinks=True is specified.
* On Windows, it now raises error if follow_symlinks=True is passed.
* On macOS, it now raises error if follow_symlinks=False is passed and
the system linkat() function is not available at runtime.
* On other platforms, it now raises error if follow_symlinks is passed
with a value that does not match the system link() function behavior
if if the behavior is not known.
Co-authored-by: Joachim Henke <37883863+jo-he@users.noreply.github.com>
Co-authored-by: Thomas Kluyver <takowl@gmail.com>
Support it for the dev_t values in mknod(), major(), minor() and makedev(),
CPU numbers in sched_setaffinity(), group numbers in setgroups(),
configuration name in fpathconf(), pathconf(), confstr(), and sysconf().
The PyThreadState field gains a reference count field to avoid
issues with PyThreadState being a dangling pointer to freed memory.
The refcount starts with a value of two: one reference is owned by the
interpreter's linked list of thread states and one reference is owned by
the OS thread. The reference count is decremented when the thread state
is removed from the interpreter's linked list and before the OS thread
calls `PyThread_hang_thread()`. The thread that decrements it to zero
frees the `PyThreadState` memory.
The `holds_gil` field is moved out of the `_status` bit field, to avoid
a data race where on thread calls `PyThreadState_Clear()`, modifying the
`_status` bit field while the OS thread reads `holds_gil` when
attempting to acquire the GIL.
The `PyThreadState.state` field now has `_Py_THREAD_SHUTTING_DOWN` as a
possible value. This corresponds to the `_PyThreadState_MustExit()`
check. This avoids race conditions in the free threading build when
checking `_PyThreadState_MustExit()`.
Add a new OS API which will read data directly into a caller provided
writeable buffer protocol object.
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
Co-authored-by: Victor Stinner <vstinner@python.org>
The PyMutex implementation supports unlocking after fork because we
clear the list of waiters in parking_lot.c. This doesn't work as well
for _PyRecursiveMutex because on some systems, such as SerenityOS, the
thread id is not preserved across fork().
This adds a `_PyRecursiveMutex` type based on `PyMutex` and uses that
for the import lock. This fixes some data races in the free-threaded
build and generally simplifies the import lock code.
This PR adds the ability to enable the GIL if it was disabled at
interpreter startup, and modifies the multi-phase module initialization
path to enable the GIL when loading a module, unless that module's spec
includes a slot indicating it can run safely without the GIL.
PEP 703 called the constant for the slot `Py_mod_gil_not_used`; I went
with `Py_MOD_GIL_NOT_USED` for consistency with gh-104148.
A warning will be issued up to once per interpreter for the first
GIL-using module that is loaded. If `-v` is given, a shorter message
will be printed to stderr every time a GIL-using module is loaded
(including the first one that issues a warning).
On Linux >= 2.6.36 with glibc < 2.27, `getcwd()` can return a relative
pathname starting with '(unreachable)'. We detect this and fail with
ENOENT, matching new glibc behaviour.
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Split `_PyThreadState_DeleteExcept` into two functions:
- `_PyThreadState_RemoveExcept` removes all thread states other than one
passed as an argument. It returns the removed thread states as a
linked list.
- `_PyThreadState_DeleteList` deletes those dead thread states. It may
call destructors, so we want to "start the world" before calling
`_PyThreadState_DeleteList` to avoid potential deadlocks.
Duane Griffin