bpo-36301: Add _Py_PreInitializeFromConfig() (GH-12536)

* Initialize _PyPreConfig.dev_mode to -1.
* _PyPreConfig_Read(): coreconfig has the priority over preconfig.
* _PyCoreConfig_Read() now calls _PyPreCmdline_Read() internally.
* config_from_cmdline() now pass _PyPreCmdline to config_read().
* Add _PyPreCmdline_Copy().

3 files changed, 18 insertions, 2 deletions

diff --git a/Include/cpython/coreconfig.h b/Include/cpython/coreconfig.h
index 8362209..bb086cb 100644
--- a/Include/cpython/coreconfig.h
+++ b/Include/cpython/coreconfig.h
@@ -115,7 +115,9 @@ typedef struct {
         .isolated = -1, \
         .use_environment = -1, \
         .coerce_c_locale = -1, \
-        .utf8_mode = -1}
+        .utf8_mode = -1, \
+        .dev_mode = -1, \
+        .allocator = NULL}
 
 
 /* --- _PyCoreConfig ---------------------------------------------- */
diff --git a/Include/cpython/pylifecycle.h b/Include/cpython/pylifecycle.h
index 1caeb98..a226de8 100644
--- a/Include/cpython/pylifecycle.h
+++ b/Include/cpython/pylifecycle.h
@@ -17,6 +17,8 @@ PyAPI_FUNC(int) Py_SetStandardStreamEncoding(const char *encoding,
 PyAPI_FUNC(_PyInitError) _Py_PreInitialize(void);
 PyAPI_FUNC(_PyInitError) _Py_PreInitializeFromPreConfig(
     _PyPreConfig *preconfig);
+PyAPI_FUNC(_PyInitError) _Py_PreInitializeFromConfig(
+    const _PyCoreConfig *coreconfig);
 
 PyAPI_FUNC(_PyInitError) _Py_InitializeCore(
     PyInterpreterState **interp,
diff --git a/Include/internal/pycore_coreconfig.h b/Include/internal/pycore_coreconfig.h
index 949bc9b..d44172e 100644
--- a/Include/internal/pycore_coreconfig.h
+++ b/Include/internal/pycore_coreconfig.h
@@ -25,11 +25,22 @@ typedef struct {
 /* Note: _PyPreCmdline_INIT sets other fields to 0/NULL */
 
 PyAPI_FUNC(void) _PyPreCmdline_Clear(_PyPreCmdline *cmdline);
+PyAPI_FUNC(int) _PyPreCmdline_Copy(_PyPreCmdline *cmdline,
+    const _PyPreCmdline *cmdline2);
 PyAPI_FUNC(_PyInitError) _PyPreCmdline_SetArgv(_PyPreCmdline *cmdline,
     const _PyArgv *args);
+PyAPI_FUNC(void) _PyPreCmdline_GetPreConfig(
+    _PyPreCmdline *cmdline,
+    const _PyPreConfig *config);
 PyAPI_FUNC(void) _PyPreCmdline_SetPreConfig(
     const _PyPreCmdline *cmdline,
     _PyPreConfig *config);
+PyAPI_FUNC(void) _PyPreCmdline_GetCoreConfig(
+    _PyPreCmdline *cmdline,
+    const _PyCoreConfig *config);
+PyAPI_FUNC(void) _PyPreCmdline_SetCoreConfig(
+    const _PyPreCmdline *cmdline,
+    _PyCoreConfig *config);
 PyAPI_FUNC(_PyInitError) _PyPreCmdline_Read(_PyPreCmdline *cmdline);
 
 
@@ -77,7 +88,8 @@ PyAPI_FUNC(void) _Py_get_env_flag(_PyPreConfig *config,
     int *flag,
     const char *name);
 PyAPI_FUNC(_PyInitError) _PyPreConfig_Read(_PyPreConfig *config,
-    const _PyArgv *args);
+    const _PyArgv *args,
+    const _PyCoreConfig *coreconfig);
 PyAPI_FUNC(int) _PyPreConfig_AsDict(const _PyPreConfig *config,
     PyObject *dict);
 PyAPI_FUNC(_PyInitError) _PyPreConfig_ReadFromArgv(_PyPreConfig *config,