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
Followup to 90fc8980bb.
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GCC complains:
Python/pylifecycle.c: In function ‘_Py_InitializeFromConfig’:
Python/pylifecycle.c:900:13: warning: ‘interp’ may be used uninitialized in this function [-Wmaybe-uninitialized]
err = _Py_InitializeMainInterpreter(interp, &main_config);
~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This seems spurious since &interp is passed to _Py_InitializeCore. Anyway, we
can easily initialize to quiet the warning.
The recursive frame pruning code always undercounted the number of elided frames
by one. That is, in the "[Previous line repeated N more times]" message, N would
always be one too few. Near the recursive pruning cutoff, one frame could be
silently dropped. That situation is demonstrated in the OP of the bug report.
The fix is to start the identical frame counter at 1.
* A pointer in `PyInterpreterState_New()` could have been `NULL` when being dereferenced.
* Memory was leaked in `PyInterpreterState_New()` when taking some error-handling code path.
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.
Py_DecodeLocale() and Py_EncodeLocale() now use the UTF-8 encoding on
Windows if Py_LegacyWindowsFSEncodingFlag is zero.
pymain_read_conf() now sets Py_LegacyWindowsFSEncodingFlag in its
loop, but restore its value at exit.
_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 Windows, the LC_CTYPE is now set to the user preferred locale at
startup: _Py_SetLocaleFromEnv(LC_CTYPE) is now called during the
Python initialization. Previously, the LC_CTYPE locale was "C" at
startup, but changed when calling setlocale(LC_CTYPE, "") or
setlocale(LC_ALL, "").
pymain_read_conf() now also calls _Py_SetLocaleFromEnv(LC_CTYPE) to
behave as _Py_InitializeCore(). Moreover, it doesn't save/restore the
LC_ALL anymore.
On Windows, standard streams like sys.stdout now always use
surrogateescape error handler by default (ignore the locale).
Standard streams like sys.stdout now use the "surrogateescape" error
handler, instead of "strict", on the POSIX locale (when the C locale is not
coerced and the UTF-8 Mode is disabled).
Add tests on sys.stdout.errors with LC_ALL=POSIX.
* _Py_InitializeCore() now sets the LC_CTYPE locale to the user
preferred locale before checking if the C locale should be coerced
or not in _PyCoreConfig_Read().
* Fix pymain_read_conf(): remember if the C locale has been coerced
when the configuration should be read again if the encoding has
changed.
Python now gets the locale encoding with C code to initialize the encoding
of standard streams like sys.stdout. Moreover, the encoding is now
initialized to the Python codec name to get a normalized encoding name and
to ensure that the codec is loaded. The change avoids importing
_bootlocale and _locale modules at startup by default.
When the PYTHONIOENCODING environment variable only contains an encoding,
the error handler is now is now set explicitly to "strict".
Rename also get_default_standard_stream_error_handler() to
get_stdio_errors().
Reduce the buffer to format the "cpXXX" string (Windows locale encoding).
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.
* The UTF-8 Mode is now also enabled by the "POSIX" locale, not only
by the "C" locale.
* On FreeBSD, Py_DecodeLocale() and Py_EncodeLocale() now also forces
the ASCII encoding if the LC_CTYPE locale is "POSIX", not only if
the LC_CTYPE locale is "C".
* test_utf8_mode.test_cmd_line() checks also that the command line
arguments are decoded from UTF-8 when the the UTF-8 Mode is enabled
with POSIX locale or C locale.
bpo-34492: Python/coreconfig.c: Add missing NULL check to _Py_wstrlist_copy().
Fix _Py_wstrlist_clear() call on a wrong list.
Reported by Svace static analyzer.
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
* 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.
Benjamin Peterson
Eric Snow
Eric V. Smith
Raymond Hettinger
guoci
Victor Stinner
Pablo Galindo
Alexey Izbyshev
costypetrisor
Peter Lamut
Serhiy Storchaka
Alexander Marshalov
jdemeyer
Xtreak