bpo-41894: Fix UnicodeDecodeError while loading native module (GH-22466)
When running in a non-UTF-8 locale, if an error occurs while importing a native Python module (say because a dependent share library is missing), the error message string returned may contain non-ASCII code points causing a UnicodeDecodeError. PyUnicode_DecodeFSDefault is used for buffers which may contain filesystem paths. For consistency with os.strerror(), PyUnicode_DecodeLocale is used for buffers which contain system error messages. While the shortname parameter is always encoded in ASCII according to PEP 489, it is left decoded using PyUnicode_FromString to minimize the changes and since it should not affect the decoding (albeit _potentially_ slower). In dynload_hpux, since the error buffer contains a message generated from a static ASCII string and the module filesystem path, PyUnicode_DecodeFSDefault is used instead of PyUnicode_DecodeLocale as is used elsewhere. * bpo-41894: Fix bugs in dynload error msg handling For both dynload_aix and dynload_hpux, properly handle the possibility that decoding strings may return NULL and when such an error happens, properly decrement any previously decoded strings and return early. In addition, in dynload_aix, ensure that we pass the decoded string *object* pathname_ob to PyErr_SetImportError instead of the original pathname buffer. Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
bpo-40422: Move _Py_closerange to fileutils.c (GH-22680)
This API is relatively lightweight and organizationally, given that it's used by multiple modules, it makes sense to move it to fileutils. Requires making sure that _posixsubprocess is compiled with the appropriate Py_BUIILD_CORE_BUILTIN macro.
bpo-40423: Optimization: use close_range(2) if available (GH-22651)
close_range(2) should be preferred at all times if it's available, otherwise we'll use closefrom(2) if available with a fallback to fdwalk(3) or plain old loop over fd range in order of most efficient to least. [note that this version does check for ENOSYS, but currently ignores all other errors] Automerge-Triggered-By: @pablogsal
bpo-40422: create a common _Py_closerange API (GH-19754)
Such an API can be used both for os.closerange and subprocess. For the latter, this yields potential improvement for platforms that have fdwalk but wouldn't have used it there. This will prove even more beneficial later for platforms that have close_range(2), as the new API will prefer that over all else if it's available. The new API is structured to look more like close_range(2), closing from [start, end] rather than the [low, high) of os.closerange(). Automerge-Triggered-By: @gpshead
bpo-41993: Fix possible issues in remove_module() (GH-22631)
* PyMapping_HasKey() is not safe because it silences all exceptions and can return incorrect result. * Informative exceptions from PyMapping_DelItem() are overridden with RuntimeError and the original exception raised before calling remove_module() is lost. * There is a race condition between PyMapping_HasKey() and PyMapping_DelItem().
bpo-42000: Cleanup the AST related C-code (GH-22641)
- Use the proper asdl sequence when creating empty arguments - Remove reduntant casts (thanks to new typed asdl_sequences) - Remove MarshalPrototypeVisitor and some utilities from asdl generator - Fix the header of `Python/ast.c` (kept from pgen times) Automerge-Triggered-By: @pablogsal