pylifecycle.c

/* Python interpreter top-level routines, including init/exit */

#include "Python.h"

#include "pycore_bytesobject.h"   // _PyBytes_InitTypes()
#include "pycore_ceval.h"         // _PyEval_FiniGIL()
#include "pycore_context.h"       // _PyContext_Init()
#include "pycore_exceptions.h"    // _PyExc_InitTypes()
#include "pycore_dict.h"          // _PyDict_Fini()
#include "pycore_fileutils.h"     // _Py_ResetForceASCII()
#include "pycore_floatobject.h"   // _PyFloat_InitTypes()
#include "pycore_genobject.h"     // _PyAsyncGen_Fini()
#include "pycore_import.h"        // _PyImport_BootstrapImp()
#include "pycore_initconfig.h"    // _PyStatus_OK()
#include "pycore_list.h"          // _PyList_Fini()
#include "pycore_long.h"          // _PyLong_InitTypes()
#include "pycore_object.h"        // _PyDebug_PrintTotalRefs()
#include "pycore_pathconfig.h"    // _PyConfig_WritePathConfig()
#include "pycore_pyerrors.h"      // _PyErr_Occurred()
#include "pycore_pylifecycle.h"   // _PyErr_Print()
#include "pycore_pymem.h"         // _PyObject_DebugMallocStats()
#include "pycore_pystate.h"       // _PyThreadState_GET()
#include "pycore_runtime.h"       // _Py_ID()
#include "pycore_runtime_init.h"  // _PyRuntimeState_INIT
#include "pycore_sliceobject.h"   // _PySlice_Fini()
#include "pycore_sysmodule.h"     // _PySys_ClearAuditHooks()
#include "pycore_traceback.h"     // _Py_DumpTracebackThreads()
#include "pycore_tuple.h"         // _PyTuple_InitTypes()
#include "pycore_typeobject.h"    // _PyTypes_InitTypes()
#include "pycore_unicodeobject.h" // _PyUnicode_InitTypes()

extern void _PyIO_Fini(void);

#include <locale.h>               // setlocale()
#include <stdlib.h>               // getenv()

#if defined(__APPLE__)
#include <mach-o/loader.h>
#endif

#ifdef HAVE_SIGNAL_H
#  include <signal.h>             // SIG_IGN
#endif

#ifdef HAVE_LANGINFO_H
#  include <langinfo.h>           // nl_langinfo(CODESET)
#endif

#ifdef HAVE_FCNTL_H
#  include <fcntl.h>              // F_GETFD
#endif

#ifdef MS_WINDOWS
#  undef BYTE
#  include "windows.h"

   extern PyTypeObject PyWindowsConsoleIO_Type;
#  define PyWindowsConsoleIO_Check(op) \
       (PyObject_TypeCheck((op), &PyWindowsConsoleIO_Type))
#endif

#define PUTS(fd, str) _Py_write_noraise(fd, str, (int)strlen(str))


#ifdef __cplusplus
extern "C" {
#endif


/* Forward declarations */
static PyStatus add_main_module(PyInterpreterState *interp);
static PyStatus init_import_site(void);
static PyStatus init_set_builtins_open(void);
static PyStatus init_sys_streams(PyThreadState *tstate);
static void wait_for_thread_shutdown(PyThreadState *tstate);
static void call_ll_exitfuncs(_PyRuntimeState *runtime);

int _Py_UnhandledKeyboardInterrupt = 0;

/* The following places the `_PyRuntime` structure in a location that can be
 * found without any external information. This is meant to ease access to the
 * interpreter state for various runtime debugging tools, but is *not* an
 * officially supported feature */

#if defined(MS_WINDOWS)

#pragma section("PyRuntime", read, write)
__declspec(allocate("PyRuntime"))

#elif defined(__APPLE__)

__attribute__((
    section(SEG_DATA ",PyRuntime")
))

#endif

/* Suppress deprecation warning for PyBytesObject.ob_shash */
_Py_COMP_DIAG_PUSH
_Py_COMP_DIAG_IGNORE_DEPR_DECLS
_PyRuntimeState _PyRuntime
#if defined(__linux__) && (defined(__GNUC__) || defined(__clang__))
__attribute__ ((section (".PyRuntime")))
#endif
= _PyRuntimeState_INIT;
_Py_COMP_DIAG_POP

static int runtime_initialized = 0;

PyStatus
_PyRuntime_Initialize(void)
{
    /* XXX We only initialize once in the process, which aligns with
       the static initialization of the former globals now found in
       _PyRuntime.  However, _PyRuntime *should* be initialized with
       every Py_Initialize() call, but doing so breaks the runtime.
       This is because the runtime state is not properly finalized
       currently. */
    if (runtime_initialized) {
        return _PyStatus_OK();
    }
    runtime_initialized = 1;

    return _PyRuntimeState_Init(&_PyRuntime);
}

void
_PyRuntime_Finalize(void)
{
    _PyRuntimeState_Fini(&_PyRuntime);
    runtime_initialized = 0;
}

int
_Py_IsFinalizing(void)
{
    return _PyRuntimeState_GetFinalizing(&_PyRuntime) != NULL;
}

/* Hack to force loading of object files */
int (*_PyOS_mystrnicmp_hack)(const char *, const char *, Py_ssize_t) = \
    PyOS_mystrnicmp; /* Python/pystrcmp.o */


/* APIs to access the initialization flags
 *
 * Can be called prior to Py_Initialize.
 */

int
_Py_IsCoreInitialized(void)
{
    return _PyRuntime.core_initialized;
}

int
Py_IsInitialized(void)
{
    return _PyRuntime.initialized;
}


/* Global initializations.  Can be undone by Py_FinalizeEx().  Don't
   call this twice without an intervening Py_FinalizeEx() call.  When
   initializations fail, a fatal error is issued and the function does
   not return.  On return, the first thread and interpreter state have
   been created.

   Locking: you must hold the interpreter lock while calling this.
   (If the lock has not yet been initialized, that's equivalent to
   having the lock, but you cannot use multiple threads.)

*/
static int
init_importlib(PyThreadState *tstate, PyObject *sysmod)
{
    assert(!_PyErr_Occurred(tstate));

    PyInterpreterState *interp = tstate->interp;
    int verbose = _PyInterpreterState_GetConfig(interp)->verbose;

    // Import _importlib through its frozen version, _frozen_importlib.
    if (verbose) {
        PySys_FormatStderr("import _frozen_importlib # frozen\n");
    }
    if (PyImport_ImportFrozenModule("_frozen_importlib") <= 0) {
        return -1;
    }
    PyObject *importlib = PyImport_AddModule("_frozen_importlib"); // borrowed
    if (importlib == NULL) {
        return -1;
    }
    interp->importlib = Py_NewRef(importlib);

    // Import the _imp module
    if (verbose) {
        PySys_FormatStderr("import _imp # builtin\n");
    }
    PyObject *imp_mod = _PyImport_BootstrapImp(tstate);
    if (imp_mod == NULL) {
        return -1;
    }
    if (_PyImport_SetModuleString("_imp", imp_mod) < 0) {
        Py_DECREF(imp_mod);
        return -1;
    }

    // Install importlib as the implementation of import
    PyObject *value = PyObject_CallMethod(importlib, "_install",
                                          "OO", sysmod, imp_mod);
    Py_DECREF(imp_mod);
    if (value == NULL) {
        return -1;
    }
    Py_DECREF(value);

    assert(!_PyErr_Occurred(tstate));
    return 0;
}


static PyStatus
init_importlib_external(PyThreadState *tstate)
{
    PyObject *value;
    value = PyObject_CallMethod(tstate->interp->importlib,
                                "_install_external_importers", "");
    if (value == NULL) {
        _PyErr_Print(tstate);
        return _PyStatus_ERR("external importer setup failed");
    }
    Py_DECREF(value);
    return _PyImportZip_Init(tstate);
}

/* Helper functions to better handle the legacy C locale
 *
 * The legacy C locale assumes ASCII as the default text encoding, which
 * causes problems not only for the CPython runtime, but also other
 * components like GNU readline.
 *
 * Accordingly, when the CLI detects it, it attempts to coerce it to a
 * more capable UTF-8 based alternative as follows:
 *
 *     if (_Py_LegacyLocaleDetected()) {
 *         _Py_CoerceLegacyLocale();
 *     }
 *
 * See the documentation of the PYTHONCOERCECLOCALE setting for more details.
 *
 * Locale coercion also impacts the default error handler for the standard
 * streams: while the usual default is "strict", the default for the legacy
 * C locale and for any of the coercion target locales is "surrogateescape".
 */

int
_Py_LegacyLocaleDetected(int warn)
{
#ifndef MS_WINDOWS
    if (!warn) {
        const char *locale_override = getenv("LC_ALL");
        if (locale_override != NULL && *locale_override != '\0') {
            /* Don't coerce C locale if the LC_ALL environment variable
               is set */
            return 0;
        }
    }

    /* On non-Windows systems, the C locale is considered a legacy locale */
    /* XXX (ncoghlan): some platforms (notably Mac OS X) don't appear to treat
     *                 the POSIX locale as a simple alias for the C locale, so
     *                 we may also want to check for that explicitly.
     */
    const char *ctype_loc = setlocale(LC_CTYPE, NULL);
    return ctype_loc != NULL && strcmp(ctype_loc, "C") == 0;
#else
    /* Windows uses code pages instead of locales, so no locale is legacy */
    return 0;
#endif
}

#ifndef MS_WINDOWS
static const char *_C_LOCALE_WARNING =
    "Python runtime initialized with LC_CTYPE=C (a locale with default ASCII "
    "encoding), which may cause Unicode compatibility problems. Using C.UTF-8, "
    "C.utf8, or UTF-8 (if available) as alternative Unicode-compatible "
    "locales is recommended.\n";

static void
emit_stderr_warning_for_legacy_locale(_PyRuntimeState *runtime)
{
    const PyPreConfig *preconfig = &runtime->preconfig;
    if (preconfig->coerce_c_locale_warn && _Py_LegacyLocaleDetected(1)) {
        PySys_FormatStderr("%s", _C_LOCALE_WARNING);
    }
}
#endif   /* !defined(MS_WINDOWS) */

typedef struct _CandidateLocale {
    const char *locale_name; /* The locale to try as a coercion target */
} _LocaleCoercionTarget;

static _LocaleCoercionTarget _TARGET_LOCALES[] = {
    {"C.UTF-8"},
    {"C.utf8"},
    {"UTF-8"},
    {NULL}
};


int
_Py_IsLocaleCoercionTarget(const char *ctype_loc)
{
    const _LocaleCoercionTarget *target = NULL;
    for (target = _TARGET_LOCALES; target->locale_name; target++) {
        if (strcmp(ctype_loc, target->locale_name) == 0) {
            return 1;
        }
    }
    return 0;
}


#ifdef PY_COERCE_C_LOCALE
static const char C_LOCALE_COERCION_WARNING[] =
    "Python detected LC_CTYPE=C: LC_CTYPE coerced to %.20s (set another locale "
    "or PYTHONCOERCECLOCALE=0 to disable this locale coercion behavior).\n";

static int
_coerce_default_locale_settings(int warn, const _LocaleCoercionTarget *target)
{
    const char *newloc = target->locale_name;

    /* Reset locale back to currently configured defaults */
    _Py_SetLocaleFromEnv(LC_ALL);

    /* Set the relevant locale environment variable */
    if (setenv("LC_CTYPE", newloc, 1)) {
        fprintf(stderr,
                "Error setting LC_CTYPE, skipping C locale coercion\n");
        return 0;
    }
    if (warn) {
        fprintf(stderr, C_LOCALE_COERCION_WARNING, newloc);
    }

    /* Reconfigure with the overridden environment variables */
    _Py_SetLocaleFromEnv(LC_ALL);
    return 1;
}
#endif

int
_Py_CoerceLegacyLocale(int warn)
{
    int coerced = 0;
#ifdef PY_COERCE_C_LOCALE
    char *oldloc = NULL;

    oldloc = _PyMem_RawStrdup(setlocale(LC_CTYPE, NULL));
    if (oldloc == NULL) {
        return coerced;
    }

    const char *locale_override = getenv("LC_ALL");
    if (locale_override == NULL || *locale_override == '\0') {
        /* LC_ALL is also not set (or is set to an empty string) */
        const _LocaleCoercionTarget *target = NULL;
        for (target = _TARGET_LOCALES; target->locale_name; target++) {
            const char *new_locale = setlocale(LC_CTYPE,
                                               target->locale_name);
            if (new_locale != NULL) {
#if !defined(_Py_FORCE_UTF8_LOCALE) && defined(HAVE_LANGINFO_H) && defined(CODESET)
                /* Also ensure that nl_langinfo works in this locale */
                char *codeset = nl_langinfo(CODESET);
                if (!codeset || *codeset == '\0') {
                    /* CODESET is not set or empty, so skip coercion */
                    new_locale = NULL;
                    _Py_SetLocaleFromEnv(LC_CTYPE);
                    continue;
                }
#endif
                /* Successfully configured locale, so make it the default */
                coerced = _coerce_default_locale_settings(warn, target);
                goto done;
            }
        }
    }
    /* No C locale warning here, as Py_Initialize will emit one later */

    setlocale(LC_CTYPE, oldloc);

done:
    PyMem_RawFree(oldloc);
#endif
    return coerced;
}

/* _Py_SetLocaleFromEnv() is a wrapper around setlocale(category, "") to
 * isolate the idiosyncrasies of different libc implementations. It reads the
 * appropriate environment variable and uses its value to select the locale for
 * 'category'. */
char *
_Py_SetLocaleFromEnv(int category)
{
    char *res;
#ifdef __ANDROID__
    const char *locale;
    const char **pvar;
#ifdef PY_COERCE_C_LOCALE
    const char *coerce_c_locale;
#endif
    const char *utf8_locale = "C.UTF-8";
    const char *env_var_set[] = {
        "LC_ALL",
        "LC_CTYPE",
        "LANG",
        NULL,
    };

    /* Android setlocale(category, "") doesn't check the environment variables
     * and incorrectly sets the "C" locale at API 24 and older APIs. We only
     * check the environment variables listed in env_var_set. */
    for (pvar=env_var_set; *pvar; pvar++) {
        locale = getenv(*pvar);
        if (locale != NULL && *locale != '\0') {
            if (strcmp(locale, utf8_locale) == 0 ||
                    strcmp(locale, "en_US.UTF-8") == 0) {
                return setlocale(category, utf8_locale);
            }
            return setlocale(category, "C");
        }
    }

    /* Android uses UTF-8, so explicitly set the locale to C.UTF-8 if none of
     * LC_ALL, LC_CTYPE, or LANG is set to a non-empty string.
     * Quote from POSIX section "8.2 Internationalization Variables":
     * "4. If the LANG environment variable is not set or is set to the empty
     * string, the implementation-defined default locale shall be used." */

#ifdef PY_COERCE_C_LOCALE
    coerce_c_locale = getenv("PYTHONCOERCECLOCALE");
    if (coerce_c_locale == NULL || strcmp(coerce_c_locale, "0") != 0) {
        /* Some other ported code may check the environment variables (e.g. in
         * extension modules), so we make sure that they match the locale
         * configuration */
        if (setenv("LC_CTYPE", utf8_locale, 1)) {
            fprintf(stderr, "Warning: failed setting the LC_CTYPE "
                            "environment variable to %s\n", utf8_locale);
        }
    }
#endif
    res = setlocale(category, utf8_locale);
#else /* !defined(__ANDROID__) */
    res = setlocale(category, "");
#endif
    _Py_ResetForceASCII();
    return res;
}


static int
interpreter_update_config(PyThreadState *tstate, int only_update_path_config)
{
    const PyConfig *config = &tstate->interp->config;

    if (!only_update_path_config) {
        PyStatus status = _PyConfig_Write(config, tstate->interp->runtime);
        if (_PyStatus_EXCEPTION(status)) {
            _PyErr_SetFromPyStatus(status);
            return -1;
        }
    }

    if (_Py_IsMainInterpreter(tstate->interp)) {
        PyStatus status = _PyPathConfig_UpdateGlobal(config);
        if (_PyStatus_EXCEPTION(status)) {
            _PyErr_SetFromPyStatus(status);
            return -1;
        }
    }

    // Update the sys module for the new configuration
    if (_PySys_UpdateConfig(tstate) < 0) {
        return -1;
    }
    return 0;
}


int
_PyInterpreterState_SetConfig(const PyConfig *src_config)
{
    PyThreadState *tstate = _PyThreadState_GET();
    int res = -1;

    PyConfig config;
    PyConfig_InitPythonConfig(&config);
    PyStatus status = _PyConfig_Copy(&config, src_config);
    if (_PyStatus_EXCEPTION(status)) {
        _PyErr_SetFromPyStatus(status);
        goto done;
    }

    status = _PyConfig_Read(&config, 1);
    if (_PyStatus_EXCEPTION(status)) {
        _PyErr_SetFromPyStatus(status);
        goto done;
    }

    status = _PyConfig_Copy(&tstate->interp->config, &config);
    if (_PyStatus_EXCEPTION(status)) {
        _PyErr_SetFromPyStatus(status);
        goto done;
    }

    res = interpreter_update_config(tstate, 0);

done:
    PyConfig_Clear(&config);
    return res;
}


/* Global initializations.  Can be undone by Py_Finalize().  Don't
   call this twice without an intervening Py_Finalize() call.

   Every call to Py_InitializeFromConfig, Py_Initialize or Py_InitializeEx
   must have a corresponding call to Py_Finalize.

   Locking: you must hold the interpreter lock while calling these APIs.
   (If the lock has not yet been initialized, that's equivalent to
   having the lock, but you cannot use multiple threads.)

*/

static PyStatus
pyinit_core_reconfigure(_PyRuntimeState *runtime,
                        PyThreadState **tstate_p,
                        const PyConfig *config)
{
    PyStatus status;
    PyThreadState *tstate = _PyThreadState_GET();
    if (!tstate) {
        return _PyStatus_ERR("failed to read thread state");
    }
    *tstate_p = tstate;

    PyInterpreterState *interp = tstate->interp;
    if (interp == NULL) {
        return _PyStatus_ERR("can't make main interpreter");
    }

    status = _PyConfig_Write(config, runtime);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyConfig_Copy(&interp->config, config);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }
    config = _PyInterpreterState_GetConfig(interp);

    if (config->_install_importlib) {
        status = _PyPathConfig_UpdateGlobal(config);
        if (_PyStatus_EXCEPTION(status)) {
            return status;
        }
    }
    return _PyStatus_OK();
}


static PyStatus
pycore_init_runtime(_PyRuntimeState *runtime,
                    const PyConfig *config)
{
    if (runtime->initialized) {
        return _PyStatus_ERR("main interpreter already initialized");
    }

    PyStatus status = _PyConfig_Write(config, runtime);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    /* Py_Finalize leaves _Py_Finalizing set in order to help daemon
     * threads behave a little more gracefully at interpreter shutdown.
     * We clobber it here so the new interpreter can start with a clean
     * slate.
     *
     * However, this may still lead to misbehaviour if there are daemon
     * threads still hanging around from a previous Py_Initialize/Finalize
     * pair :(
     */
    _PyRuntimeState_SetFinalizing(runtime, NULL);

    status = _Py_HashRandomization_Init(config);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyInterpreterState_Enable(runtime);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }
    return _PyStatus_OK();
}


static PyStatus
init_interp_create_gil(PyThreadState *tstate)
{
    PyStatus status;

    /* finalize_interp_delete() comment explains why _PyEval_FiniGIL() is
       only called here. */
    _PyEval_FiniGIL(tstate->interp);

    /* Auto-thread-state API */
    status = _PyGILState_SetTstate(tstate);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    /* Create the GIL and take it */
    status = _PyEval_InitGIL(tstate);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    return _PyStatus_OK();
}


static PyStatus
pycore_create_interpreter(_PyRuntimeState *runtime,
                          const PyConfig *config,
                          PyThreadState **tstate_p)
{
    /* Auto-thread-state API */
    PyStatus status = _PyGILState_Init(runtime);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    PyInterpreterState *interp = PyInterpreterState_New();
    if (interp == NULL) {
        return _PyStatus_ERR("can't make main interpreter");
    }
    assert(_Py_IsMainInterpreter(interp));

    status = _PyConfig_Copy(&interp->config, config);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    PyThreadState *tstate = PyThreadState_New(interp);
    if (tstate == NULL) {
        return _PyStatus_ERR("can't make first thread");
    }
    (void) PyThreadState_Swap(tstate);

    status = init_interp_create_gil(tstate);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    *tstate_p = tstate;
    return _PyStatus_OK();
}


static PyStatus
pycore_init_global_objects(PyInterpreterState *interp)
{
    PyStatus status;

    _PyFloat_InitState(interp);

    status = _PyUnicode_InitGlobalObjects(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    _PyUnicode_InitState(interp);

    return _PyStatus_OK();
}


static PyStatus
pycore_init_types(PyInterpreterState *interp)
{
    PyStatus status;

    status = _PyTypes_InitState(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyTypes_InitTypes(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyBytes_InitTypes(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyLong_InitTypes(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyUnicode_InitTypes(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyFloat_InitTypes(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyTuple_InitTypes(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    if (_PyExc_InitTypes(interp) < 0) {
        return _PyStatus_ERR("failed to initialize an exception type");
    }

    status = _PyExc_InitGlobalObjects(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyExc_InitState(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyErr_InitTypes(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyContext_Init(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }
    return _PyStatus_OK();
}


static PyStatus
pycore_init_builtins(PyThreadState *tstate)
{
    PyInterpreterState *interp = tstate->interp;

    PyObject *bimod = _PyBuiltin_Init(interp);
    if (bimod == NULL) {
        goto error;
    }

    if (_PyImport_FixupBuiltin(bimod, "builtins", interp->modules) < 0) {
        goto error;
    }

    PyObject *builtins_dict = PyModule_GetDict(bimod);
    if (builtins_dict == NULL) {
        goto error;
    }
    Py_INCREF(builtins_dict);
    interp->builtins = builtins_dict;

    PyObject *isinstance = PyDict_GetItem(builtins_dict, &_Py_ID(isinstance));
    assert(isinstance);
    interp->callable_cache.isinstance = isinstance;
    PyObject *len = PyDict_GetItem(builtins_dict, &_Py_ID(len));
    assert(len);
    interp->callable_cache.len = len;
    PyObject *list_append = _PyType_Lookup(&PyList_Type, &_Py_ID(append));
    assert(list_append);
    interp->callable_cache.list_append = list_append;

    if (_PyBuiltins_AddExceptions(bimod) < 0) {
        return _PyStatus_ERR("failed to add exceptions to builtins");
    }

    interp->builtins_copy = PyDict_Copy(interp->builtins);
    if (interp->builtins_copy == NULL) {
        goto error;
    }
    Py_DECREF(bimod);

    // Get the __import__ function
    PyObject *import_func = _PyDict_GetItemStringWithError(interp->builtins,
                                                           "__import__");
    if (import_func == NULL) {
        goto error;
    }
    interp->import_func = Py_NewRef(import_func);

    assert(!_PyErr_Occurred(tstate));
    return _PyStatus_OK();

error:
    Py_XDECREF(bimod);
    return _PyStatus_ERR("can't initialize builtins module");
}


static PyStatus
pycore_interp_init(PyThreadState *tstate)
{
    PyInterpreterState *interp = tstate->interp;
    PyStatus status;
    PyObject *sysmod = NULL;

    // Create singletons before the first PyType_Ready() call, since
    // PyType_Ready() uses singletons like the Unicode empty string (tp_doc)
    // and the empty tuple singletons (tp_bases).
    status = pycore_init_global_objects(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    // The GC must be initialized before the first GC collection.
    status = _PyGC_Init(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }
    // Intern strings in deep-frozen modules first so that others
    // can use it instead of creating a heap allocated string.
    if (_Py_Deepfreeze_Init() < 0) {
        return _PyStatus_ERR("failed to initialize deep-frozen modules");
    }

    status = pycore_init_types(interp);
    if (_PyStatus_EXCEPTION(status)) {
        goto done;
    }

    if (_PyWarnings_InitState(interp) < 0) {
        return _PyStatus_ERR("can't initialize warnings");
    }

    status = _PyAtExit_Init(interp);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PySys_Create(tstate, &sysmod);
    if (_PyStatus_EXCEPTION(status)) {
        goto done;
    }

    status = pycore_init_builtins(tstate);
    if (_PyStatus_EXCEPTION(status)) {
        goto done;
    }

    const PyConfig *config = _PyInterpreterState_GetConfig(interp);
    if (config->_install_importlib) {
        /* This call sets up builtin and frozen import support */
        if (init_importlib(tstate, sysmod) < 0) {
            return _PyStatus_ERR("failed to initialize importlib");
        }
    }

done:
    /* sys.modules['sys'] contains a strong reference to the module */
    Py_XDECREF(sysmod);
    return status;
}


static PyStatus
pyinit_config(_PyRuntimeState *runtime,
              PyThreadState **tstate_p,
              const PyConfig *config)
{
    PyStatus status = pycore_init_runtime(runtime, config);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    PyThreadState *tstate;
    status = pycore_create_interpreter(runtime, config, &tstate);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }
    *tstate_p = tstate;

    status = pycore_interp_init(tstate);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    /* Only when we get here is the runtime core fully initialized */
    runtime->core_initialized = 1;
    return _PyStatus_OK();
}


PyStatus
_Py_PreInitializeFromPyArgv(const PyPreConfig *src_config, const _PyArgv *args)
{
    PyStatus status;

    if (src_config == NULL) {
        return _PyStatus_ERR("preinitialization config is NULL");
    }

    status = _PyRuntime_Initialize();
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }
    _PyRuntimeState *runtime = &_PyRuntime;

    if (runtime->preinitialized) {
        /* If it's already configured: ignored the new configuration */
        return _PyStatus_OK();
    }

    /* Note: preinitialized remains 1 on error, it is only set to 0
       at exit on success. */
    runtime->preinitializing = 1;

    PyPreConfig config;

    status = _PyPreConfig_InitFromPreConfig(&config, src_config);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyPreConfig_Read(&config, args);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    status = _PyPreConfig_Write(&config);
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }

    runtime->preinitializing = 0;
    runtime->preinitialized = 1;
    return _PyStatus_OK();
}


PyStatus
Py_PreInitializeFromBytesArgs(const PyPreConfig *src_config, Py_ssize_t argc, char **argv)
{
    _PyArgv args = {.use_bytes_argv = 1, .argc = argc, .bytes_argv = argv};
    return _Py_PreInitializeFromPyArgv(src_config, &args);
}


PyStatus
Py_PreInitializeFromArgs(const PyPreConfig *src_config, Py_ssize_t argc, wchar_t **argv)
{
    _PyArgv args = {.use_bytes_argv = 0, .argc = argc, .wchar_argv = argv};
    return _Py_PreInitializeFromPyArgv(src_config, &args);
}


PyStatus
Py_PreInitialize(const PyPreConfig *src_config)
{
    return _Py_PreInitializeFromPyArgv(src_config, NULL);
}


PyStatus
_Py_PreInitializeFromConfig(const PyConfig *config,
                            const _PyArgv *args)
{
    assert(config != NULL);

    PyStatus status = _PyRuntime_Initialize();
    if (_PyStatus_EXCEPTION(status)) {
        return status;
    }
    _PyRuntimeState *runtime = &_PyRuntime;

    if (runtime->preinitialized) {
        /* Already initialized: do nothing */
        return _PyStatus_OK();
    }

    PyPreConfig preconfig;

    _PyPreConfig_InitFromConfig(&preconfig, config);