bpo-36763: Implement the PEP 587 (GH-13592)

* Add a whole new documentation page:
  "Python Initialization Configuration"
* PyWideStringList_Append() return type is now PyStatus,
  instead of int
* PyInterpreterState_New() now calls PyConfig_Clear() if
  PyConfig_InitPythonConfig() fails.
* Rename files:

  * Python/coreconfig.c => Python/initconfig.c
  * Include/cpython/coreconfig.h => Include/cpython/initconfig.h
  * Include/internal/: pycore_coreconfig.h => pycore_initconfig.h

* Rename structures

  * _PyCoreConfig => PyConfig
  * _PyPreConfig => PyPreConfig
  * _PyInitError => PyStatus
  * _PyWstrList => PyWideStringList

* Rename PyConfig fields:

  * use_module_search_paths => module_search_paths_set
  * module_search_path_env => pythonpath_env

* Rename PyStatus field: _func => func
* PyInterpreterState: rename core_config field to config
* Rename macros and functions:

  * _PyCoreConfig_SetArgv() => PyConfig_SetBytesArgv()
  * _PyCoreConfig_SetWideArgv() => PyConfig_SetArgv()
  * _PyCoreConfig_DecodeLocale() => PyConfig_SetBytesString()
  * _PyInitError_Failed() => PyStatus_Exception()
  * _Py_INIT_ERROR_TYPE_xxx enums => _PyStatus_TYPE_xxx
  * _Py_UnixMain() => Py_BytesMain()
  * _Py_ExitInitError() => Py_ExitStatusException()
  * _Py_PreInitializeFromArgs() => Py_PreInitializeFromBytesArgs()
  * _Py_PreInitializeFromWideArgs() => Py_PreInitializeFromArgs()
  * _Py_PreInitialize() => Py_PreInitialize()
  * _Py_RunMain() => Py_RunMain()
  * _Py_InitializeFromConfig() => Py_InitializeFromConfig()
  * _Py_INIT_XXX() => _PyStatus_XXX()
  * _Py_INIT_FAILED() => _PyStatus_EXCEPTION()

* Rename 'err' PyStatus variables to 'status'
* Convert RUN_CODE() macro to config_run_code() static inline function
* Remove functions:

  * _Py_InitializeFromArgs()
  * _Py_InitializeFromWideArgs()
  * _PyInterpreterState_GetCoreConfig()

9 files changed, 287 insertions, 291 deletions

diff --git a/Include/Python.h b/Include/Python.h
index 17ad5b3..d6e5b13 100644
--- a/Include/Python.h
+++ b/Include/Python.h
@@ -129,7 +129,7 @@
 #include "codecs.h"
 #include "pyerrors.h"
 
-#include "cpython/coreconfig.h"
+#include "cpython/initconfig.h"
 #include "pystate.h"
 #include "context.h"
 
diff --git a/Include/cpython/coreconfig.h b/Include/cpython/initconfig.h
index ef5fde2..a98b91a 100644
--- a/Include/cpython/coreconfig.h
+++ b/Include/cpython/initconfig.h
@@ -5,56 +5,49 @@
 extern "C" {
 #endif
 
-/* --- _PyInitError ----------------------------------------------- */
+/* --- PyStatus ----------------------------------------------- */
 
 typedef struct {
     enum {
-        _Py_INIT_ERR_TYPE_OK=0,
-        _Py_INIT_ERR_TYPE_ERROR=1,
-        _Py_INIT_ERR_TYPE_EXIT=2
+        _PyStatus_TYPE_OK=0,
+        _PyStatus_TYPE_ERROR=1,
+        _PyStatus_TYPE_EXIT=2
     } _type;
-    const char *_func;
+    const char *func;
     const char *err_msg;
     int exitcode;
-} _PyInitError;
+} PyStatus;
 
-PyAPI_FUNC(_PyInitError) _PyInitError_Ok(void);
-PyAPI_FUNC(_PyInitError) _PyInitError_Error(const char *err_msg);
-PyAPI_FUNC(_PyInitError) _PyInitError_NoMemory(void);
-PyAPI_FUNC(_PyInitError) _PyInitError_Exit(int exitcode);
-PyAPI_FUNC(int) _PyInitError_IsError(_PyInitError err);
-PyAPI_FUNC(int) _PyInitError_IsExit(_PyInitError err);
-PyAPI_FUNC(int) _PyInitError_Failed(_PyInitError err);
+PyAPI_FUNC(PyStatus) PyStatus_Ok(void);
+PyAPI_FUNC(PyStatus) PyStatus_Error(const char *err_msg);
+PyAPI_FUNC(PyStatus) PyStatus_NoMemory(void);
+PyAPI_FUNC(PyStatus) PyStatus_Exit(int exitcode);
+PyAPI_FUNC(int) PyStatus_IsError(PyStatus err);
+PyAPI_FUNC(int) PyStatus_IsExit(PyStatus err);
+PyAPI_FUNC(int) PyStatus_Exception(PyStatus err);
 
-/* --- _PyWstrList ------------------------------------------------ */
+/* --- PyWideStringList ------------------------------------------------ */
 
 typedef struct {
     /* If length is greater than zero, items must be non-NULL
        and all items strings must be non-NULL */
     Py_ssize_t length;
     wchar_t **items;
-} _PyWstrList;
+} PyWideStringList;
 
+PyAPI_FUNC(PyStatus) PyWideStringList_Append(PyWideStringList *list,
+    const wchar_t *item);
 
-/* --- _PyPreConfig ----------------------------------------------- */
-
-#define _Py_CONFIG_VERSION 1
-
-typedef enum {
-    /* Py_Initialize() API: backward compatibility with Python 3.6 and 3.7 */
-    _PyConfig_INIT_COMPAT = 1,
-    _PyConfig_INIT_PYTHON = 2,
-    _PyConfig_INIT_ISOLATED = 3
-} _PyConfigInitEnum;
 
+/* --- PyPreConfig ----------------------------------------------- */
 
 typedef struct {
     int _config_version;  /* Internal configuration version,
                              used for ABI compatibility */
     int _config_init;     /* _PyConfigInitEnum value */
 
-    /* Parse _Py_PreInitializeFromArgs() arguments?
-       See _PyCoreConfig.parse_argv */
+    /* Parse Py_PreInitializeFromBytesArgs() arguments?
+       See PyConfig.parse_argv */
     int parse_argv;
 
     /* If greater than 0, enable isolated mode: sys.path contains
@@ -124,22 +117,22 @@ typedef struct {
     /* Memory allocator: PYTHONMALLOC env var.
        See PyMemAllocatorName for valid values. */
     int allocator;
-} _PyPreConfig;
+} PyPreConfig;
 
-PyAPI_FUNC(void) _PyPreConfig_InitPythonConfig(_PyPreConfig *config);
-PyAPI_FUNC(void) _PyPreConfig_InitIsolatedConfig(_PyPreConfig *config);
+PyAPI_FUNC(void) PyPreConfig_InitPythonConfig(PyPreConfig *config);
+PyAPI_FUNC(void) PyPreConfig_InitIsolatedConfig(PyPreConfig *config);
 
 
-/* --- _PyCoreConfig ---------------------------------------------- */
+/* --- PyConfig ---------------------------------------------- */
 
 typedef struct {
     int _config_version;  /* Internal configuration version,
                              used for ABI compatibility */
     int _config_init;     /* _PyConfigInitEnum value */
 
-    int isolated;         /* Isolated mode? see _PyPreConfig.isolated */
-    int use_environment;  /* Use environment variables? see _PyPreConfig.use_environment */
-    int dev_mode;         /* Development mode? See _PyPreConfig.dev_mode */
+    int isolated;         /* Isolated mode? see PyPreConfig.isolated */
+    int use_environment;  /* Use environment variables? see PyPreConfig.use_environment */
+    int dev_mode;         /* Development mode? See PyPreConfig.dev_mode */
 
     /* Install signal handlers? Yes by default. */
     int install_signal_handlers;
@@ -207,7 +200,7 @@ typedef struct {
 
        If argv is empty, an empty string is added to ensure that sys.argv
        always exists and is never empty. */
-    _PyWstrList argv;
+    PyWideStringList argv;
 
     /* Program name:
 
@@ -219,8 +212,8 @@ typedef struct {
        - Use "python" on Windows, or "python3 on other platforms. */
     wchar_t *program_name;
 
-    _PyWstrList xoptions;     /* Command line -X options */
-    _PyWstrList warnoptions;  /* Warnings options */
+    PyWideStringList xoptions;     /* Command line -X options */
+    PyWideStringList warnoptions;  /* Warnings options */
 
     /* If equal to zero, disable the import of the module site and the
        site-dependent manipulations of sys.path that it entails. Also disable
@@ -347,17 +340,37 @@ typedef struct {
     int legacy_windows_stdio;
 #endif
 
+    /* Value of the --check-hash-based-pycs command line option:
+
+       - "default" means the 'check_source' flag in hash-based pycs
+         determines invalidation
+       - "always" causes the interpreter to hash the source file for
+         invalidation regardless of value of 'check_source' bit
+       - "never" causes the interpreter to always assume hash-based pycs are
+         valid
+
+       The default value is "default".
+
+       See PEP 552 "Deterministic pycs" for more details. */
+    wchar_t *check_hash_pycs_mode;
+
     /* --- Path configuration inputs ------------ */
 
-    wchar_t *module_search_path_env; /* PYTHONPATH environment variable */
+    /* If greater than 0, suppress _PyPathConfig_Calculate() warnings on Unix.
+       The parameter has no effect on Windows.
+
+       If set to -1 (default), inherit !Py_FrozenFlag value. */
+    int pathconfig_warnings;
+
+    wchar_t *pythonpath_env; /* PYTHONPATH environment variable */
     wchar_t *home;          /* PYTHONHOME environment variable,
                                see also Py_SetPythonHome(). */
 
     /* --- Path configuration outputs ----------- */
 
-    int use_module_search_paths;  /* If non-zero, use module_search_paths */
-    _PyWstrList module_search_paths;  /* sys.path paths. Computed if
-                                       use_module_search_paths is equal
+    int module_search_paths_set;  /* If non-zero, use module_search_paths */
+    PyWideStringList module_search_paths;  /* sys.path paths. Computed if
+                                       module_search_paths_set is equal
                                        to zero. */
 
     wchar_t *executable;    /* sys.executable */
@@ -384,48 +397,28 @@ typedef struct {
        Needed by freeze_importlib. */
     int _install_importlib;
 
-    /* Value of the --check-hash-based-pycs command line option:
-
-       - "default" means the 'check_source' flag in hash-based pycs
-         determines invalidation
-       - "always" causes the interpreter to hash the source file for
-         invalidation regardless of value of 'check_source' bit
-       - "never" causes the interpreter to always assume hash-based pycs are
-         valid
-
-       The default value is "default".
-
-       See PEP 552 "Deterministic pycs" for more details. */
-    wchar_t *check_hash_pycs_mode;
-
-    /* If greater than 0, suppress _PyPathConfig_Calculate() warnings on Unix.
-       The parameter has no effect on Windows.
-
-       If set to -1 (default), inherit !Py_FrozenFlag value. */
-    int pathconfig_warnings;
-
     /* If equal to 0, stop Python initialization before the "main" phase */
     int _init_main;
 
-} _PyCoreConfig;
+} PyConfig;
 
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_InitPythonConfig(_PyCoreConfig *config);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_InitIsolatedConfig(_PyCoreConfig *config);
-PyAPI_FUNC(void) _PyCoreConfig_Clear(_PyCoreConfig *);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_SetString(
-    _PyCoreConfig *config,
+PyAPI_FUNC(PyStatus) PyConfig_InitPythonConfig(PyConfig *config);
+PyAPI_FUNC(PyStatus) PyConfig_InitIsolatedConfig(PyConfig *config);
+PyAPI_FUNC(void) PyConfig_Clear(PyConfig *);
+PyAPI_FUNC(PyStatus) PyConfig_SetString(
+    PyConfig *config,
     wchar_t **config_str,
     const wchar_t *str);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_DecodeLocale(
-    _PyCoreConfig *config,
+PyAPI_FUNC(PyStatus) PyConfig_SetBytesString(
+    PyConfig *config,
     wchar_t **config_str,
     const char *str);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_Read(_PyCoreConfig *config);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_SetArgv(
-    _PyCoreConfig *config,
+PyAPI_FUNC(PyStatus) PyConfig_Read(PyConfig *config);
+PyAPI_FUNC(PyStatus) PyConfig_SetBytesArgv(
+    PyConfig *config,
     Py_ssize_t argc,
     char * const *argv);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_SetWideArgv(_PyCoreConfig *config,
+PyAPI_FUNC(PyStatus) PyConfig_SetArgv(PyConfig *config,
     Py_ssize_t argc,
     wchar_t * const *argv);
 
diff --git a/Include/cpython/pylifecycle.h b/Include/cpython/pylifecycle.h
index ba56664..2f3a0db 100644
--- a/Include/cpython/pylifecycle.h
+++ b/Include/cpython/pylifecycle.h
@@ -14,14 +14,14 @@ PyAPI_FUNC(int) Py_SetStandardStreamEncoding(const char *encoding,
 
 /* PEP 432 Multi-phase initialization API (Private while provisional!) */
 
-PyAPI_FUNC(_PyInitError) _Py_PreInitialize(
-    const _PyPreConfig *src_config);
-PyAPI_FUNC(_PyInitError) _Py_PreInitializeFromArgs(
-    const _PyPreConfig *src_config,
+PyAPI_FUNC(PyStatus) Py_PreInitialize(
+    const PyPreConfig *src_config);
+PyAPI_FUNC(PyStatus) Py_PreInitializeFromBytesArgs(
+    const PyPreConfig *src_config,
     Py_ssize_t argc,
     char **argv);
-PyAPI_FUNC(_PyInitError) _Py_PreInitializeFromWideArgs(
-    const _PyPreConfig *src_config,
+PyAPI_FUNC(PyStatus) Py_PreInitializeFromArgs(
+    const PyPreConfig *src_config,
     Py_ssize_t argc,
     wchar_t **argv);
 
@@ -30,22 +30,22 @@ PyAPI_FUNC(int) _Py_IsCoreInitialized(void);
 
 /* Initialization and finalization */
 
-PyAPI_FUNC(_PyInitError) _Py_InitializeFromConfig(
-    const _PyCoreConfig *config);
-PyAPI_FUNC(_PyInitError) _Py_InitializeFromArgs(
-    const _PyCoreConfig *config,
+PyAPI_FUNC(PyStatus) Py_InitializeFromConfig(
+    const PyConfig *config);
+PyAPI_FUNC(PyStatus) _Py_InitializeFromArgs(
+    const PyConfig *config,
     Py_ssize_t argc,
     char * const *argv);
-PyAPI_FUNC(_PyInitError) _Py_InitializeFromWideArgs(
-    const _PyCoreConfig *config,
+PyAPI_FUNC(PyStatus) _Py_InitializeFromWideArgs(
+    const PyConfig *config,
     Py_ssize_t argc,
     wchar_t * const *argv);
-PyAPI_FUNC(_PyInitError) _Py_InitializeMain(void);
+PyAPI_FUNC(PyStatus) _Py_InitializeMain(void);
 
-PyAPI_FUNC(int) _Py_RunMain(void);
+PyAPI_FUNC(int) Py_RunMain(void);
 
 
-PyAPI_FUNC(void) _Py_NO_RETURN _Py_ExitInitError(_PyInitError err);
+PyAPI_FUNC(void) _Py_NO_RETURN Py_ExitStatusException(PyStatus err);
 
 /* Py_PyAtExit is for the atexit module, Py_AtExit is for low-level
  * exit functions.
diff --git a/Include/cpython/pystate.h b/Include/cpython/pystate.h
index 94331f3..6b7663f 100644
--- a/Include/cpython/pystate.h
+++ b/Include/cpython/pystate.h
@@ -6,13 +6,11 @@
 extern "C" {
 #endif
 
-#include "cpython/coreconfig.h"
+#include "cpython/initconfig.h"
 
 PyAPI_FUNC(int) _PyInterpreterState_RequiresIDRef(PyInterpreterState *);
 PyAPI_FUNC(void) _PyInterpreterState_RequireIDRef(PyInterpreterState *, int);
 
-PyAPI_FUNC(_PyCoreConfig *) _PyInterpreterState_GetCoreConfig(PyInterpreterState *);
-
 PyAPI_FUNC(PyObject *) _PyInterpreterState_GetMainModule(PyInterpreterState *);
 
 /* State unique per thread */
diff --git a/Include/internal/pycore_coreconfig.h b/Include/internal/pycore_coreconfig.h
deleted file mode 100644
index b17737a..0000000
--- a/Include/internal/pycore_coreconfig.h
+++ /dev/null
@@ -1,163 +0,0 @@
-#ifndef Py_INTERNAL_CORECONFIG_H
-#define Py_INTERNAL_CORECONFIG_H
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#ifndef Py_BUILD_CORE
-#  error "this header requires Py_BUILD_CORE define"
-#endif
-
-#include "pycore_pystate.h"   /* _PyRuntimeState */
-
-/* --- _PyInitError ----------------------------------------------- */
-
-/* Almost all errors causing Python initialization to fail */
-#ifdef _MSC_VER
-   /* Visual Studio 2015 doesn't implement C99 __func__ in C */
-#  define _Py_INIT_GET_FUNC() __FUNCTION__
-#else
-#  define _Py_INIT_GET_FUNC() __func__
-#endif
-
-#define _Py_INIT_OK() \
-    (_PyInitError){._type = _Py_INIT_ERR_TYPE_OK,}
-    /* other fields are set to 0 */
-#define _Py_INIT_ERR(ERR_MSG) \
-    (_PyInitError){ \
-        ._type = _Py_INIT_ERR_TYPE_ERROR, \
-        ._func = _Py_INIT_GET_FUNC(), \
-        .err_msg = (ERR_MSG)}
-        /* other fields are set to 0 */
-#define _Py_INIT_NO_MEMORY() _Py_INIT_ERR("memory allocation failed")
-#define _Py_INIT_EXIT(EXITCODE) \
-    (_PyInitError){ \
-        ._type = _Py_INIT_ERR_TYPE_EXIT, \
-        .exitcode = (EXITCODE)}
-#define _Py_INIT_IS_ERROR(err) \
-    (err._type == _Py_INIT_ERR_TYPE_ERROR)
-#define _Py_INIT_IS_EXIT(err) \
-    (err._type == _Py_INIT_ERR_TYPE_EXIT)
-#define _Py_INIT_FAILED(err) \
-    (err._type != _Py_INIT_ERR_TYPE_OK)
-
-/* --- _PyWstrList ------------------------------------------------ */
-
-#define _PyWstrList_INIT (_PyWstrList){.length = 0, .items = NULL}
-
-#ifndef NDEBUG
-PyAPI_FUNC(int) _PyWstrList_CheckConsistency(const _PyWstrList *list);
-#endif
-PyAPI_FUNC(void) _PyWstrList_Clear(_PyWstrList *list);
-PyAPI_FUNC(int) _PyWstrList_Copy(_PyWstrList *list,
-    const _PyWstrList *list2);
-PyAPI_FUNC(int) _PyWstrList_Append(_PyWstrList *list,
-    const wchar_t *item);
-PyAPI_FUNC(PyObject*) _PyWstrList_AsList(const _PyWstrList *list);
-PyAPI_FUNC(int) _PyWstrList_Extend(_PyWstrList *list,
-    const _PyWstrList *list2);
-
-
-/* --- _PyArgv ---------------------------------------------------- */
-
-typedef struct {
-    Py_ssize_t argc;
-    int use_bytes_argv;
-    char * const *bytes_argv;
-    wchar_t * const *wchar_argv;
-} _PyArgv;
-
-PyAPI_FUNC(_PyInitError) _PyArgv_AsWstrList(const _PyArgv *args,
-    _PyWstrList *list);
-
-
-/* --- Helper functions ------------------------------------------- */
-
-PyAPI_FUNC(int) _Py_str_to_int(
-    const char *str,
-    int *result);
-PyAPI_FUNC(const wchar_t*) _Py_get_xoption(
-    const _PyWstrList *xoptions,
-    const wchar_t *name);
-PyAPI_FUNC(const char*) _Py_GetEnv(
-    int use_environment,
-    const char *name);
-PyAPI_FUNC(void) _Py_get_env_flag(
-    int use_environment,
-    int *flag,
-    const char *name);
-
-/* Py_GetArgcArgv() helper */
-PyAPI_FUNC(void) _Py_ClearArgcArgv(void);
-
-
-/* --- _PyPreCmdline ------------------------------------------------- */
-
-typedef struct {
-    _PyWstrList argv;
-    _PyWstrList xoptions;     /* "-X value" option */
-    int isolated;             /* -I option */
-    int use_environment;      /* -E option */
-    int dev_mode;             /* -X dev and PYTHONDEVMODE */
-} _PyPreCmdline;
-
-#define _PyPreCmdline_INIT \
-    (_PyPreCmdline){ \
-        .use_environment = -1, \
-        .isolated = -1, \
-        .dev_mode = -1}
-/* Note: _PyPreCmdline_INIT sets other fields to 0/NULL */
-
-PyAPI_FUNC(void) _PyPreCmdline_Clear(_PyPreCmdline *cmdline);
-PyAPI_FUNC(_PyInitError) _PyPreCmdline_SetArgv(_PyPreCmdline *cmdline,
-    const _PyArgv *args);
-PyAPI_FUNC(int) _PyPreCmdline_SetCoreConfig(
-    const _PyPreCmdline *cmdline,
-    _PyCoreConfig *config);
-PyAPI_FUNC(_PyInitError) _PyPreCmdline_Read(_PyPreCmdline *cmdline,
-    const _PyPreConfig *preconfig);
-
-
-/* --- _PyPreConfig ----------------------------------------------- */
-
-PyAPI_FUNC(void) _PyPreConfig_InitCompatConfig(_PyPreConfig *config);
-PyAPI_FUNC(void) _PyPreConfig_InitFromCoreConfig(
-    _PyPreConfig *config,
-    const _PyCoreConfig *coreconfig);
-PyAPI_FUNC(void) _PyPreConfig_InitFromPreConfig(
-    _PyPreConfig *config,
-    const _PyPreConfig *config2);
-PyAPI_FUNC(void) _PyPreConfig_Copy(_PyPreConfig *config,
-    const _PyPreConfig *config2);
-PyAPI_FUNC(PyObject*) _PyPreConfig_AsDict(const _PyPreConfig *config);
-PyAPI_FUNC(void) _PyPreConfig_GetCoreConfig(_PyPreConfig *config,
-    const _PyCoreConfig *core_config);
-PyAPI_FUNC(_PyInitError) _PyPreConfig_Read(_PyPreConfig *config,
-    const _PyArgv *args);
-PyAPI_FUNC(_PyInitError) _PyPreConfig_Write(const _PyPreConfig *config);
-
-
-/* --- _PyCoreConfig ---------------------------------------------- */
-
-PyAPI_FUNC(void) _PyCoreConfig_InitCompatConfig(_PyCoreConfig *config);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_Copy(
-    _PyCoreConfig *config,
-    const _PyCoreConfig *config2);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_InitPathConfig(_PyCoreConfig *config);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_SetPathConfig(
-    const _PyCoreConfig *config);
-PyAPI_FUNC(void) _PyCoreConfig_Write(const _PyCoreConfig *config,
-    _PyRuntimeState *runtime);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_SetPyArgv(
-    _PyCoreConfig *config,
-    const _PyArgv *args);
-
-
-/* --- Function used for testing ---------------------------------- */
-
-PyAPI_FUNC(PyObject*) _Py_GetConfigsAsDict(void);
-
-#ifdef __cplusplus
-}
-#endif
-#endif /* !Py_INTERNAL_CORECONFIG_H */
diff --git a/Include/internal/pycore_initconfig.h b/Include/internal/pycore_initconfig.h
new file mode 100644
index 0000000..c0b3d95
--- /dev/null
+++ b/Include/internal/pycore_initconfig.h
@@ -0,0 +1,168 @@
+#ifndef Py_INTERNAL_CORECONFIG_H
+#define Py_INTERNAL_CORECONFIG_H
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef Py_BUILD_CORE
+#  error "this header requires Py_BUILD_CORE define"
+#endif
+
+#include "pycore_pystate.h"   /* _PyRuntimeState */
+
+/* --- PyStatus ----------------------------------------------- */
+
+/* Almost all errors causing Python initialization to fail */
+#ifdef _MSC_VER
+   /* Visual Studio 2015 doesn't implement C99 __func__ in C */
+#  define _PyStatus_GET_FUNC() __FUNCTION__
+#else
+#  define _PyStatus_GET_FUNC() __func__
+#endif
+
+#define _PyStatus_OK() \
+    (PyStatus){._type = _PyStatus_TYPE_OK,}
+    /* other fields are set to 0 */
+#define _PyStatus_ERR(ERR_MSG) \
+    (PyStatus){ \
+        ._type = _PyStatus_TYPE_ERROR, \
+        .func = _PyStatus_GET_FUNC(), \
+        .err_msg = (ERR_MSG)}
+        /* other fields are set to 0 */
+#define _PyStatus_NO_MEMORY() _PyStatus_ERR("memory allocation failed")
+#define _PyStatus_EXIT(EXITCODE) \
+    (PyStatus){ \
+        ._type = _PyStatus_TYPE_EXIT, \
+        .exitcode = (EXITCODE)}
+#define _PyStatus_IS_ERROR(err) \
+    (err._type == _PyStatus_TYPE_ERROR)
+#define _PyStatus_IS_EXIT(err) \
+    (err._type == _PyStatus_TYPE_EXIT)
+#define _PyStatus_EXCEPTION(err) \
+    (err._type != _PyStatus_TYPE_OK)
+
+/* --- PyWideStringList ------------------------------------------------ */
+
+#define PyWideStringList_INIT (PyWideStringList){.length = 0, .items = NULL}
+
+#ifndef NDEBUG
+PyAPI_FUNC(int) _PyWideStringList_CheckConsistency(const PyWideStringList *list);
+#endif
+PyAPI_FUNC(void) _PyWideStringList_Clear(PyWideStringList *list);
+PyAPI_FUNC(int) _PyWideStringList_Copy(PyWideStringList *list,
+    const PyWideStringList *list2);
+PyAPI_FUNC(PyStatus) _PyWideStringList_Extend(PyWideStringList *list,
+    const PyWideStringList *list2);
+PyAPI_FUNC(PyObject*) _PyWideStringList_AsList(const PyWideStringList *list);
+
+
+/* --- _PyArgv ---------------------------------------------------- */
+
+typedef struct {
+    Py_ssize_t argc;
+    int use_bytes_argv;
+    char * const *bytes_argv;
+    wchar_t * const *wchar_argv;
+} _PyArgv;
+
+PyAPI_FUNC(PyStatus) _PyArgv_AsWstrList(const _PyArgv *args,
+    PyWideStringList *list);
+
+
+/* --- Helper functions ------------------------------------------- */
+
+PyAPI_FUNC(int) _Py_str_to_int(
+    const char *str,
+    int *result);
+PyAPI_FUNC(const wchar_t*) _Py_get_xoption(
+    const PyWideStringList *xoptions,
+    const wchar_t *name);
+PyAPI_FUNC(const char*) _Py_GetEnv(
+    int use_environment,
+    const char *name);
+PyAPI_FUNC(void) _Py_get_env_flag(
+    int use_environment,
+    int *flag,
+    const char *name);
+
+/* Py_GetArgcArgv() helper */
+PyAPI_FUNC(void) _Py_ClearArgcArgv(void);
+
+
+/* --- _PyPreCmdline ------------------------------------------------- */
+
+typedef struct {
+    PyWideStringList argv;
+    PyWideStringList xoptions;     /* "-X value" option */
+    int isolated;             /* -I option */
+    int use_environment;      /* -E option */
+    int dev_mode;             /* -X dev and PYTHONDEVMODE */
+} _PyPreCmdline;
+
+#define _PyPreCmdline_INIT \
+    (_PyPreCmdline){ \
+        .use_environment = -1, \
+        .isolated = -1, \
+        .dev_mode = -1}
+/* Note: _PyPreCmdline_INIT sets other fields to 0/NULL */
+
+extern void _PyPreCmdline_Clear(_PyPreCmdline *cmdline);
+extern PyStatus _PyPreCmdline_SetArgv(_PyPreCmdline *cmdline,
+    const _PyArgv *args);
+extern PyStatus _PyPreCmdline_SetConfig(
+    const _PyPreCmdline *cmdline,
+    PyConfig *config);
+extern PyStatus _PyPreCmdline_Read(_PyPreCmdline *cmdline,
+    const PyPreConfig *preconfig);
+
+
+/* --- PyPreConfig ----------------------------------------------- */
+
+PyAPI_FUNC(void) _PyPreConfig_InitCompatConfig(PyPreConfig *preconfig);
+extern void _PyPreConfig_InitFromConfig(
+    PyPreConfig *preconfig,
+    const PyConfig *config);
+extern void _PyPreConfig_InitFromPreConfig(
+    PyPreConfig *preconfig,
+    const PyPreConfig *config2);
+extern PyObject* _PyPreConfig_AsDict(const PyPreConfig *preconfig);
+extern void _PyPreConfig_GetConfig(PyPreConfig *preconfig,
+    const PyConfig *config);
+extern PyStatus _PyPreConfig_Read(PyPreConfig *preconfig,
+    const _PyArgv *args);
+extern PyStatus _PyPreConfig_Write(const PyPreConfig *preconfig);
+
+
+/* --- PyConfig ---------------------------------------------- */
+
+#define _Py_CONFIG_VERSION 1
+
+typedef enum {
+    /* Py_Initialize() API: backward compatibility with Python 3.6 and 3.7 */
+    _PyConfig_INIT_COMPAT = 1,
+    _PyConfig_INIT_PYTHON = 2,
+    _PyConfig_INIT_ISOLATED = 3
+} _PyConfigInitEnum;
+
+PyAPI_FUNC(void) _PyConfig_InitCompatConfig(PyConfig *config);
+extern PyStatus _PyConfig_Copy(
+    PyConfig *config,
+    const PyConfig *config2);
+extern PyStatus _PyConfig_InitPathConfig(PyConfig *config);
+extern PyStatus _PyConfig_SetPathConfig(
+    const PyConfig *config);
+extern void _PyConfig_Write(const PyConfig *config,
+    _PyRuntimeState *runtime);
+extern PyStatus _PyConfig_SetPyArgv(
+    PyConfig *config,
+    const _PyArgv *args);
+
+
+/* --- Function used for testing ---------------------------------- */
+
+PyAPI_FUNC(PyObject*) _Py_GetConfigsAsDict(void);
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* !Py_INTERNAL_CORECONFIG_H */
diff --git a/Include/internal/pycore_pathconfig.h b/Include/internal/pycore_pathconfig.h
index bee3911..be12c6f 100644
--- a/Include/internal/pycore_pathconfig.h
+++ b/Include/internal/pycore_pathconfig.h
@@ -37,17 +37,17 @@ typedef struct _PyPathConfig {
 
 PyAPI_DATA(_PyPathConfig) _Py_path_config;
 
-PyAPI_FUNC(void) _PyPathConfig_ClearGlobal(void);
-PyAPI_FUNC(_PyInitError) _PyPathConfig_SetGlobal(
-    const struct _PyPathConfig *config);
-
-PyAPI_FUNC(_PyInitError) _PyPathConfig_Calculate_impl(
-    _PyPathConfig *config,
-    const _PyCoreConfig *core_config);
-PyAPI_FUNC(int) _PyPathConfig_ComputeSysPath0(
-    const _PyWstrList *argv,
+extern void _PyPathConfig_ClearGlobal(void);
+extern PyStatus _PyPathConfig_SetGlobal(
+    const struct _PyPathConfig *pathconfig);
+
+extern PyStatus _PyPathConfig_Calculate(
+    _PyPathConfig *pathconfig,
+    const PyConfig *config);
+extern int _PyPathConfig_ComputeSysPath0(
+    const PyWideStringList *argv,
     PyObject **path0);
-PyAPI_FUNC(int) _Py_FindEnvConfigValue(
+extern int _Py_FindEnvConfigValue(
     FILE *env_file,
     const wchar_t *key,
     wchar_t *value,
diff --git a/Include/internal/pycore_pylifecycle.h b/Include/internal/pycore_pylifecycle.h
index 13a31c2..69761ce 100644
--- a/Include/internal/pycore_pylifecycle.h
+++ b/Include/internal/pycore_pylifecycle.h
@@ -8,20 +8,20 @@ extern "C" {
 #  error "this header requires Py_BUILD_CORE define"
 #endif
 
-#include "pycore_coreconfig.h"   /* _PyArgv */
+#include "pycore_initconfig.h"   /* _PyArgv */
 #include "pycore_pystate.h"      /* _PyRuntimeState */
 
 /* True if the main interpreter thread exited due to an unhandled
  * KeyboardInterrupt exception, suggesting the user pressed ^C. */
 PyAPI_DATA(int) _Py_UnhandledKeyboardInterrupt;
 
-PyAPI_FUNC(int) _Py_UnixMain(int argc, char **argv);
+PyAPI_FUNC(int) Py_BytesMain(int argc, char **argv);
 
 extern int _Py_SetFileSystemEncoding(
     const char *encoding,
     const char *errors);
 extern void _Py_ClearFileSystemEncoding(void);
-extern _PyInitError _PyUnicode_InitEncodings(PyInterpreterState *interp);
+extern PyStatus _PyUnicode_InitEncodings(PyInterpreterState *interp);
 #ifdef MS_WINDOWS
 extern int _PyUnicode_EnableLegacyWindowsFSEncoding(void);
 #endif
@@ -32,30 +32,30 @@ PyAPI_FUNC(int) _Py_IsLocaleCoercionTarget(const char *ctype_loc);
 
 /* Various one-time initializers */
 
-extern _PyInitError _PyUnicode_Init(void);
+extern PyStatus _PyUnicode_Init(void);
 extern int _PyStructSequence_Init(void);
 extern int _PyLong_Init(void);
-extern _PyInitError _PyFaulthandler_Init(int enable);
+extern PyStatus _PyFaulthandler_Init(int enable);
 extern int _PyTraceMalloc_Init(int enable);
 extern PyObject * _PyBuiltin_Init(void);
-extern _PyInitError _PySys_Create(
+extern PyStatus _PySys_Create(
     _PyRuntimeState *runtime,
     PyInterpreterState *interp,
     PyObject **sysmod_p);
-extern _PyInitError _PySys_SetPreliminaryStderr(PyObject *sysdict);
+extern PyStatus _PySys_SetPreliminaryStderr(PyObject *sysdict);
 extern int _PySys_InitMain(
     _PyRuntimeState *runtime,
     PyInterpreterState *interp);
-extern _PyInitError _PyImport_Init(PyInterpreterState *interp);
-extern _PyInitError _PyExc_Init(void);
-extern _PyInitError _PyErr_Init(void);
-extern _PyInitError _PyBuiltins_AddExceptions(PyObject * bltinmod);
-extern _PyInitError _PyImportHooks_Init(void);
+extern PyStatus _PyImport_Init(PyInterpreterState *interp);
+extern PyStatus _PyExc_Init(void);
+extern PyStatus _PyErr_Init(void);
+extern PyStatus _PyBuiltins_AddExceptions(PyObject * bltinmod);
+extern PyStatus _PyImportHooks_Init(void);
 extern int _PyFloat_Init(void);
-extern _PyInitError _Py_HashRandomization_Init(const _PyCoreConfig *);
+extern PyStatus _Py_HashRandomization_Init(const PyConfig *);
 
-extern _PyInitError _PyTypes_Init(void);
-extern _PyInitError _PyImportZip_Init(PyInterpreterState *interp);
+extern PyStatus _PyTypes_Init(void);
+extern PyStatus _PyImportZip_Init(PyInterpreterState *interp);
 
 
 /* Various internal finalizers */
@@ -94,11 +94,11 @@ extern void _PyGILState_Fini(_PyRuntimeState *runtime);
 
 PyAPI_FUNC(void) _PyGC_DumpShutdownStats(_PyRuntimeState *runtime);
 
-PyAPI_FUNC(_PyInitError) _Py_PreInitializeFromPyArgv(
-    const _PyPreConfig *src_config,
+PyAPI_FUNC(PyStatus) _Py_PreInitializeFromPyArgv(
+    const PyPreConfig *src_config,
     const _PyArgv *args);
-PyAPI_FUNC(_PyInitError) _Py_PreInitializeFromCoreConfig(
-    const _PyCoreConfig *coreconfig,
+PyAPI_FUNC(PyStatus) _Py_PreInitializeFromConfig(
+    const PyConfig *config,
     const _PyArgv *args);
 
 
diff --git a/Include/internal/pycore_pystate.h b/Include/internal/pycore_pystate.h
index ef1d8a0..3ab4009 100644
--- a/Include/internal/pycore_pystate.h
+++ b/Include/internal/pycore_pystate.h
@@ -8,7 +8,7 @@ extern "C" {
 #  error "this header requires Py_BUILD_CORE define"
 #endif
 
-#include "cpython/coreconfig.h"
+#include "cpython/initconfig.h"
 #include "fileobject.h"
 #include "pystate.h"
 #include "pythread.h"
@@ -106,7 +106,7 @@ struct _is {
         _Py_error_handler error_handler;
     } fs_codec;
 
-    _PyCoreConfig core_config;
+    PyConfig config;
 #ifdef HAVE_DLOPEN
     int dlopenflags;
 #endif
@@ -193,7 +193,7 @@ struct _gilstate_runtime_state {
 /* Full Python runtime state */
 
 typedef struct pyruntimestate {
-    /* Is Python pre-initialized? Set to 1 by _Py_PreInitialize() */
+    /* Is Python pre-initialized? Set to 1 by Py_PreInitialize() */
     int pre_initialized;
 
     /* Is Python core initialized? Set to 1 by _Py_InitializeCore() */
@@ -234,7 +234,7 @@ typedef struct pyruntimestate {
     struct _ceval_runtime_state ceval;
     struct _gilstate_runtime_state gilstate;
 
-    _PyPreConfig preconfig;
+    PyPreConfig preconfig;
 
     Py_OpenCodeHookFunction open_code_hook;
     void *open_code_userdata;
@@ -248,13 +248,13 @@ typedef struct pyruntimestate {
 /* Note: _PyRuntimeState_INIT sets other fields to 0/NULL */
 
 PyAPI_DATA(_PyRuntimeState) _PyRuntime;
-PyAPI_FUNC(_PyInitError) _PyRuntimeState_Init(_PyRuntimeState *runtime);
+PyAPI_FUNC(PyStatus) _PyRuntimeState_Init(_PyRuntimeState *runtime);
 PyAPI_FUNC(void) _PyRuntimeState_Fini(_PyRuntimeState *runtime);
 PyAPI_FUNC(void) _PyRuntimeState_ReInitThreads(_PyRuntimeState *runtime);
 
 /* Initialize _PyRuntimeState.
    Return NULL on success, or return an error message on failure. */
-PyAPI_FUNC(_PyInitError) _PyRuntime_Initialize(void);
+PyAPI_FUNC(PyStatus) _PyRuntime_Initialize(void);
 
 PyAPI_FUNC(void) _PyRuntime_Finalize(void);
 
@@ -307,7 +307,7 @@ PyAPI_FUNC(PyThreadState *) _PyThreadState_Swap(
     struct _gilstate_runtime_state *gilstate,
     PyThreadState *newts);
 
-PyAPI_FUNC(_PyInitError) _PyInterpreterState_Enable(_PyRuntimeState *runtime);
+PyAPI_FUNC(PyStatus) _PyInterpreterState_Enable(_PyRuntimeState *runtime);
 PyAPI_FUNC(void) _PyInterpreterState_DeleteExceptMain(_PyRuntimeState *runtime);
 
 PyAPI_FUNC(void) _PyGILState_Reinit(_PyRuntimeState *runtime);