When os.fork() is called (on platforms that support it) all threads but the current one are destroyed in the child process. Consequently we must ensure that all but the associated interpreter are likewise destroyed. The main interpreter is critical for runtime operation, so we must ensure that fork only happens in the main interpreter.
https://bugs.python.org/issue34651
* Add _testcapi.get_coreconfig() to get the _PyCoreConfig of the
interpreter
* test.pythoninfo now gets the core configuration using
_testcapi.get_coreconfig()
Use the core configuration of the interpreter, rather
than using global configuration variables. For example, replace
Py_QuietFlag with core_config->quiet.
* Py_FileSystemDefaultEncoding and Py_FileSystemDefaultEncodeErrors
default value is now NULL: initfsencoding() set them
during Python initialization.
* Document how Python chooses the filesystem encoding and error
handler.
* Add an assertion to _PyCoreConfig_Read().
Add support for the "surrogatepass" error handler in
PyUnicode_DecodeFSDefault() and PyUnicode_EncodeFSDefault()
for the UTF-8 encoding.
Changes:
* _Py_DecodeUTF8Ex() and _Py_EncodeUTF8Ex() now support the
surrogatepass error handler (_Py_ERROR_SURROGATEPASS).
* _Py_DecodeLocaleEx() and _Py_EncodeLocaleEx() now use
the _Py_error_handler enum instead of "int surrogateescape" to pass
the error handler. These functions now return -3 if the error
handler is unknown.
* Add unit tests on _Py_DecodeLocaleEx() and _Py_EncodeLocaleEx()
in test_codecs.
* Rename get_error_handler() to _Py_GetErrorHandler() and expose it
as a private function.
* _freeze_importlib doesn't need config.filesystem_errors="strict"
workaround anymore.
_PyCoreConfig_Read() is now responsible to choose the filesystem
encoding and error handler. Using Py_Main(), the encoding is now
chosen even before calling Py_Initialize().
_PyCoreConfig.filesystem_encoding is now the reference, instead of
Py_FileSystemDefaultEncoding, for the Python filesystem encoding.
Changes:
* Add filesystem_encoding and filesystem_errors to _PyCoreConfig
* _PyCoreConfig_Read() now reads the locale encoding for the file
system encoding.
* PyUnicode_EncodeFSDefault() and PyUnicode_DecodeFSDefaultAndSize()
now use the interpreter configuration rather than
Py_FileSystemDefaultEncoding and Py_FileSystemDefaultEncodeErrors
global configuration variables.
* Add _Py_SetFileSystemEncoding() and _Py_ClearFileSystemEncoding()
private functions to only modify Py_FileSystemDefaultEncoding and
Py_FileSystemDefaultEncodeErrors in coreconfig.c.
* _Py_CoerceLegacyLocale() now takes an int rather than
_PyCoreConfig for the warning.
On HP-UX with C or POSIX locale, sys.getfilesystemencoding() now returns
"ascii" instead of "roman8" (when the UTF-8 Mode is disabled and the C locale
is not coerced).
nl_langinfo(CODESET) announces "roman8" whereas it uses the Latin1
encoding in practice.
bpo-31650, bpo-34170: Replace _Py_CheckHashBasedPycsMode with
_PyCoreConfig._check_hash_pycs_mode. Modify PyInit__imp() and
zipimport to get the parameter from the current interpreter core
configuration.
Remove Include/internal/import.h file.
* Add Include/coreconfig.h
* Move config_*() and _PyCoreConfig_*() functions from Modules/main.c
to a new Python/coreconfig.c file.
* Inline _Py_ReadHashSeed() into config_init_hash_seed()
* Move global configuration variables to coreconfig.c
* Config: Rename ignore_environment field to use_environment.
* _PyCoreConfig_Read(): if isolated is set, use_environment and
site_import are now always set to 0.
* Inline pymain_free_raw() into pymain_free()
* Move config_init_warnoptions() call into pymain_read_conf_impl()
* _PyCoreConfig_Read(): don't replace values if they are already set:
faulthandler, pycache_prefix, home.
* Inline cmdline_get_env_flags() into config_read_env_vars():
_PyCoreConfig_Read() now reads much more environment variables like
PYTHONVERBOSE.
* Allow to override faulthandler and allocator even if dev_mode=1.
PYTHONMALLOC is now the priority over PYTHONDEVMODE.
* Fix _PyCoreConfig_Copy(): copy also install_signal_handlers,
coerce_c_locale and coerce_c_locale_warn
* _PyCoreConfig.install_signal_handlers default is now 1: install
signals by default
* Fix also a compiler warning: don't define _PyPathConfig type twice.
* If _Py_InitializeCore() is called twice, the second call now copies
and apply (partially) the new configuration.
* Rename _Py_CommandLineDetails to _PyCmdline
* Move more code into pymain_init(). The core configuration created
by Py_Main() is new destroyed before running Python to reduce the
memory footprint.
* _Py_InitializeCore() now returns the created interpreter.
_Py_InitializeMainInterpreter() now expects an interpreter.
* Remove _Py_InitializeEx_Private(): _freeze_importlib now uses
_Py_InitializeFromConfig()
* _PyCoreConfig_InitPathConfig() now only computes the path
configuration if needed.
Add more fields to _PyCoreConfig:
* _check_hash_pycs_mode
* bytes_warning
* debug
* inspect
* interactive
* legacy_windows_fs_encoding
* legacy_windows_stdio
* optimization_level
* quiet
* unbuffered_stdio
* user_site_directory
* verbose
* write_bytecode
Changes:
* Remove pymain_get_global_config() and pymain_set_global_config()
which became useless. These functions have been replaced by
_PyCoreConfig_GetGlobalConfig() and
_PyCoreConfig_SetGlobalConfig().
* sys.flags.dont_write_bytecode value is now restricted to 1 even if
-B option is specified multiple times on the command line.
* PyThreadState_Clear() now uses the config from the current
interpreter rather than using global Py_VerboseFlag
* _PyCoreConfig: add isolated and site_import attributes
* Replace Py_IgnoreEnvironment with config->ignore_environment when
reading the current configuration
* _PyCoreConfig_Read() now sets ignore_environment, utf8_mode,
isolated and site_import from Py_IgnoreEnvironment, Py_UTF8Mode,
Py_IsolatedFlag and Py_NoSiteFlag
* _Py_InitializeCore() now sets Py_xxx flags from the configuration
* pymain_read_conf() now uses _PyCoreConfig_Copy() to save/restore
the configuration.
* Rename _disable_importlib of _PyCoreConfig to _install_importlib
* _PyCoreConfig_SetGlobalConfig() now also set
Py_HashRandomizationFlag
* Replace !Py_NoSiteFlag with core_config->site_import
* _PyCoreConfig_Read() no longer directly modifies Py_IsolatedFlag
and Py_NoSiteFlag global configuration flags. The function now
requires two pointers to integer, so these flags can be set later,
to avoid side effets in _PyCoreConfig_Read().
* pathconfig_global_init() now leaves Py_IsolatedFlag and
Py_NoSiteFlag unchanged.
* Fix pathconfig_global_init(): avoid computing the path
configuration twice, use _PyCoreConfig_SetPathConfig().
Rework _PyCoreConfig_Read() function which *reads* core configuration
to not *modify* the path configuration.
A new _PyCoreConfig_SetPathConfig() function now recreates the path
configuration from the core configuration. This function is now
called very late in _Py_InitializeCore(), just before calling
initimport().
Changes:
* Add _PyCoreConfig.dll_path
* Py_SetPath() now fails with a fatal python error on memory
allocation failure.
* Rename _PyPathConfig_Calculate() to _PyPathConfig_Calculate_impl()
* Replace _PyPathConfig_Init() with _PyPathConfig_Calculate(): the
function now requires a _PyPathConfig
* Add _PyPathConfig_SetGlobal() to set the _Py_path_config global
variable.
* Add _PyCoreConfig_InitPathConfig(): compute the path configuration
* Add _PyCoreConfig_SetPathConfig(): set path configuration from core
configuration
* Rename wstrlist_append() to _Py_wstrlist_append()
* _Py_wstrlist_append() now handles integer overflow.
In some development setups it is inconvenient or impossible to write bytecode
caches to the code tree, but the bytecode caches are still useful. The
PYTHONPYCACHEPREFIX environment variable allows specifying an alternate
location for cached bytecode files, within which a directory tree mirroring the code
tree will be created. This cache tree is then used (for both reading and writing)
instead of the local `__pycache__` subdirectory within each source directory.
Exposed at runtime as sys.pycache_prefix (defaulting to None), and can
be set from the CLI as "-X pycache_prefix=path".
Patch by Carl Meyer.
During development of the limited API support for PySide,
we saw an error in a macro that accessed a type field.
This patch fixes the 7 errors in the Python headers.
Macros which were not written as capitals were implemented
as function.
To do the necessary analysis again, a script was included that
parses all headers and looks for "->tp_" in serctions which can
be reached with active limited API.
It is easily possible to call this script as a test.
Error listing:
../../Include/objimpl.h:243
#define PyObject_IS_GC(o) (PyType_IS_GC(Py_TYPE(o)) && \
(Py_TYPE(o)->tp_is_gc == NULL || Py_TYPE(o)->tp_is_gc(o)))
Action: commented only
../../Include/objimpl.h:362
#define PyType_SUPPORTS_WEAKREFS(t) ((t)->tp_weaklistoffset > 0)
Action: commented only
../../Include/objimpl.h:364
#define PyObject_GET_WEAKREFS_LISTPTR(o) \
((PyObject **) (((char *) (o)) + Py_TYPE(o)->tp_weaklistoffset))
Action: commented only
../../Include/pyerrors.h:143
#define PyExceptionClass_Name(x) \
((char *)(((PyTypeObject*)(x))->tp_name))
Action: implemented function
../../Include/abstract.h:593
#define PyIter_Check(obj) \
((obj)->ob_type->tp_iternext != NULL && \
(obj)->ob_type->tp_iternext != &_PyObject_NextNotImplemented)
Action: implemented function
../../Include/abstract.h:713
#define PyIndex_Check(obj) \
((obj)->ob_type->tp_as_number != NULL && \
(obj)->ob_type->tp_as_number->nb_index != NULL)
Action: implemented function
../../Include/abstract.h:924
#define PySequence_ITEM(o, i)\
( Py_TYPE(o)->tp_as_sequence->sq_item(o, i) )
Action: commented only
For bpo-32604 I added extra subinterpreter-related tests (see #6914), which caused a few buildbots to crash. This patch fixes the crash by ensuring that refcounts in channels are handled properly.
Remove the docstring attribute of AST types and restore docstring
expression as a first stmt in their body.
Co-authored-by: INADA Naoki <methane@users.noreply.github.com>
* Set the limited API version for PyImport_GetModule and PyOS_*Fork
functions.
* Add PyImport_GetModule and Py_UTF8Mode in PC/python3.def.
* Add several functions in Doc/data/refcounts.dat.
* Added new opcode END_ASYNC_FOR.
* Setting global StopAsyncIteration no longer breaks "async for" loops.
* Jumping into an "async for" loop is now disabled.
* Jumping out of an "async for" loop no longer corrupts the stack.
* Simplify the compiler.
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.
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