bpo-36301: Add _PyRuntime.pre_initialized (GH-12457)

* Add _PyRuntime.pre_initialized: set to 1 when Python
  is pre-initialized
* Add _Py_PreInitialize() and _Py_PreInitializeFromPreConfig().
* _PyCoreConfig_Read() now calls  _Py_PreInitialize().
* Move _PyPreConfig_GetGlobalConfig() and
  _PyCoreConfig_GetGlobalConfig() calls from main.c to preconfig.c
  and coreconfig.c.

1 files changed, 10 insertions, 19 deletions

diff --git a/Modules/main.c b/Modules/main.c
index df4eca5..57cf862 100644
--- a/Modules/main.c
+++ b/Modules/main.c
@@ -283,32 +283,30 @@ _PyMainInterpreterConfig_Read(_PyMainInterpreterConfig *main_config,
 /* --- pymain_init() ---------------------------------------------- */
 
 static _PyInitError
-preconfig_read_write(_PyPreConfig *config, const _PyArgv *args)
+pymain_init_preconfig(_PyPreConfig *config, const _PyArgv *args)
 {
-    _PyPreConfig_GetGlobalConfig(config);
-
     _PyInitError err = _PyPreConfig_ReadFromArgv(config, args);
     if (_Py_INIT_FAILED(err)) {
         return err;
     }
 
-    return _PyPreConfig_Write(config);
+    return _Py_PreInitializeFromPreConfig(config);
 }
 
 
 static _PyInitError
-config_read_write(_PyCoreConfig *config, const _PyArgv *args,
-                  const _PyPreConfig *preconfig)
+pymain_init_coreconfig(_PyCoreConfig *config, const _PyArgv *args,
+                       const _PyPreConfig *preconfig,
+                       PyInterpreterState **interp_p)
 {
-    _PyCoreConfig_GetGlobalConfig(config);
-
     _PyInitError err = _PyCoreConfig_ReadFromArgv(config, args, preconfig);
     if (_Py_INIT_FAILED(err)) {
         return err;
     }
 
     _PyCoreConfig_Write(config);
-    return _Py_INIT_OK();
+
+    return _Py_InitializeCore(interp_p, config);
 }
 
 
@@ -356,24 +354,17 @@ pymain_init(const _PyArgv *args, PyInterpreterState **interp_p)
     _PyCoreConfig local_config = _PyCoreConfig_INIT;
     _PyCoreConfig *config = &local_config;
 
-    err = preconfig_read_write(preconfig, args);
+    err = pymain_init_preconfig(preconfig, args);
     if (_Py_INIT_FAILED(err)) {
         goto done;
     }
 
-    err = config_read_write(config, args, preconfig);
-    if (_Py_INIT_FAILED(err)) {
-        goto done;
-    }
-
-    PyInterpreterState *interp;
-    err = _Py_InitializeCore(&interp, config);
+    err = pymain_init_coreconfig(config, args, preconfig, interp_p);
     if (_Py_INIT_FAILED(err)) {
         goto done;
     }
-    *interp_p = interp;
 
-    err = pymain_init_python_main(interp);
+    err = pymain_init_python_main(*interp_p);
     if (_Py_INIT_FAILED(err)) {
         goto done;
     }