fstat may block for long time if the file descriptor is on a
non-responsive NFS server, hanging all threads. Most fstat() calls are
handled by _Py_fstat(), releasing the GIL internally, but but
_Py_fstat_noraise() does not release the GIL, and most calls release the
GIL explicitly around it.
This patch fixes last 2 calls to _Py_fstat_no_raise(), avoiding hangs
when calling:
- mmap.mmap()
- os.urandom()
- random.seed()
(cherry picked from commit 4484f9dca9)
Co-authored-by: Nir Soffer <nirsof@gmail.com>
When comprehensions switched to using a nested scope, the old
code for generating a temporary name to hold the accumulation
target became redundant, but was never actually removed.
Patch by Nitish Chandra.
(cherry picked from commit 3a087beddd)
Co-authored-by: Nitish Chandra <nitishchandrachinta@gmail.com>
Fix a crash on fork when using a custom memory allocator (ex: using
PYTHONMALLOC env var).
_PyGILState_Reinit() and _PyInterpreterState_Enable() now use the
default RAW memory allocator to allocate a new interpreters mutex on
fork.
(cherry picked from commit 5d92647102)
Co-authored-by: Victor Stinner <victor.stinner@gmail.com>
The CPython runtime assumes that there is a one-to-one relationship (for a given interpreter) between PyThreadState and OS threads. Sending and receiving on a channel in the same interpreter was causing crashes because of this (specifically due to a check in PyThreadState_Swap()). The solution is to not switch threads if the interpreter is the same.
(cherry picked from commit f53d9f2778)
Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>
This function expects the destination buffer size to be given
in wide characters, not bytes.
(cherry picked from commit b3b4a9d300)
Co-authored-by: Alexey Izbyshev <izbyshev@users.noreply.github.com>
Fix a rare but potential pre-exec child process deadlock in subprocess on POSIX systems when marking file descriptors inheritable on exec in the child process. This bug appears to have been introduced in 3.4 with the inheritable file descriptors support.
This also changes Python/fileutils.c `set_inheritable` to use the "slow" two `fcntl` syscall path instead of the "fast" single `ioctl` syscall path when asked to be async signal safe (by way of being asked not to raise exceptions). `ioctl` is not a POSIX async-signal-safe approved function.
ref: http://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html
(cherry picked from commit c1e46e94de)
Co-authored-by: Alexey Izbyshev <izbyshev@users.noreply.github.com>
Fix typos found by codespell in docs, docstrings, and comments.
(cherry picked from commit c3d9508ff2)
Co-authored-by: Leo Arias <leo.arias@canonical.com>
Clarify that the level argument is used to determine whether to
perform absolute or relative imports: 0 is absolute, while a positive number
is the number of parent directories to search relative to the current module.
(cherry picked from commit 461d225b19)
Co-authored-by: oldk <oldk1331@users.noreply.github.com>
