bpo-36763: Add _PyPreConfig._config_init (GH-13481)

* _PyPreConfig_GetGlobalConfig() and  _PyCoreConfig_GetGlobalConfig()
  now do nothing if the configuration was not initialized with
  _PyPreConfig_InitCompatConfig() and _PyCoreConfig_InitCompatConfig()
* Remove utf8_mode=-2 special case: use utf8_mode=-1 instead.
* Fix _PyPreConfig_InitPythonConfig():

  * isolated = 0 instead of -1
  * use_environment = 1 instead of -1

* Rename _PyConfig_INIT to  _PyConfig_INIT_COMPAT
* Rename _PyPreConfig_Init() to _PyPreConfig_InitCompatConfig()
* Rename _PyCoreConfig_Init() to _PyCoreConfig_InitCompatConfig()
* PyInterpreterState_New() now uses _PyCoreConfig_InitPythonConfig()
  as default configuration, but it's very quickly overriden anyway.
* _freeze_importlib.c uses _PyCoreConfig_SetString() to set
  program_name.
* Cleanup preconfig_init_utf8_mode(): cmdline is always non-NULL.

2 files changed, 13 insertions, 13 deletions

diff --git a/Include/cpython/coreconfig.h b/Include/cpython/coreconfig.h
index decfb70..ef5fde2 100644
--- a/Include/cpython/coreconfig.h
+++ b/Include/cpython/coreconfig.h
@@ -40,9 +40,18 @@ typedef struct {
 
 #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;
+
+
 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 */
@@ -107,10 +116,7 @@ typedef struct {
        Set to 0 by "-X utf8=0" and PYTHONUTF8=0.
 
        If equals to -1, it is set to 1 if the LC_CTYPE locale is "C" or
-       "POSIX", otherwise it is set to 0.
-
-       If equals to -2, inherit Py_UTF8Mode value value (which is equal to 0
-       by default). */
+       "POSIX", otherwise it is set to 0. Inherit Py_UTF8Mode value value. */
     int utf8_mode;
 
     int dev_mode;           /* Development mode. PYTHONDEVMODE, -X dev */
@@ -126,16 +132,10 @@ PyAPI_FUNC(void) _PyPreConfig_InitIsolatedConfig(_PyPreConfig *config);
 
 /* --- _PyCoreConfig ---------------------------------------------- */
 
-typedef enum {
-    _PyCoreConfig_INIT = 0,
-    _PyCoreConfig_INIT_PYTHON = 1,
-    _PyCoreConfig_INIT_ISOLATED = 2
-} _PyCoreConfigInitEnum;
-
 typedef struct {
     int _config_version;  /* Internal configuration version,
                              used for ABI compatibility */
-    int _config_init;     /* _PyCoreConfigInitEnum value */
+    int _config_init;     /* _PyConfigInitEnum value */
 
     int isolated;         /* Isolated mode? see _PyPreConfig.isolated */
     int use_environment;  /* Use environment variables? see _PyPreConfig.use_environment */
diff --git a/Include/internal/pycore_coreconfig.h b/Include/internal/pycore_coreconfig.h
index 324e0b8..b17737a 100644
--- a/Include/internal/pycore_coreconfig.h
+++ b/Include/internal/pycore_coreconfig.h
@@ -120,7 +120,7 @@ PyAPI_FUNC(_PyInitError) _PyPreCmdline_Read(_PyPreCmdline *cmdline,
 
 /* --- _PyPreConfig ----------------------------------------------- */
 
-PyAPI_FUNC(void) _PyPreConfig_Init(_PyPreConfig *config);
+PyAPI_FUNC(void) _PyPreConfig_InitCompatConfig(_PyPreConfig *config);
 PyAPI_FUNC(void) _PyPreConfig_InitFromCoreConfig(
     _PyPreConfig *config,
     const _PyCoreConfig *coreconfig);
@@ -139,7 +139,7 @@ PyAPI_FUNC(_PyInitError) _PyPreConfig_Write(const _PyPreConfig *config);
 
 /* --- _PyCoreConfig ---------------------------------------------- */
 
-PyAPI_FUNC(void) _PyCoreConfig_Init(_PyCoreConfig *config);
+PyAPI_FUNC(void) _PyCoreConfig_InitCompatConfig(_PyCoreConfig *config);
 PyAPI_FUNC(_PyInitError) _PyCoreConfig_Copy(
     _PyCoreConfig *config,
     const _PyCoreConfig *config2);