bpo-36142: Rework error reporting in pymain_main() (GH-12113)

Add a new _Py_INIT_EXIT() macro to be able to exit Python with an
exitcode using _PyInitError API. Rewrite function calls by
pymain_main() to use _PyInitError.

Changes:

* Remove _PyMain.err and _PyMain.status field
* Add _Py_INIT_EXIT() macro and _PyInitError.exitcode field.
* Rename _Py_FatalInitError() to _Py_ExitInitError().

3 files changed, 14 insertions, 9 deletions

diff --git a/Python/frozenmain.c b/Python/frozenmain.c
index 6160909..6554aa7 100644
--- a/Python/frozenmain.c
+++ b/Python/frozenmain.c
@@ -86,7 +86,7 @@ Py_FrozenMain(int argc, char **argv)
     /* No need to call _PyCoreConfig_Clear() since we didn't allocate any
        memory: program_name is a constant string. */
     if (_Py_INIT_FAILED(err)) {
-        _Py_FatalInitError(err);
+        _Py_ExitInitError(err);
     }
 
 #ifdef MS_WINDOWS
diff --git a/Python/pathconfig.c b/Python/pathconfig.c
index eadc09b..f96f015 100644
--- a/Python/pathconfig.c
+++ b/Python/pathconfig.c
@@ -408,7 +408,7 @@ pathconfig_global_init(void)
 
 error:
     _PyCoreConfig_Clear(&config);
-    _Py_FatalInitError(err);
+    _Py_ExitInitError(err);
 }
 
 
diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index 1d65d3b..088e7aa 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -960,7 +960,7 @@ Py_InitializeEx(int install_sigs)
     _PyCoreConfig_Clear(&config);
 
     if (_Py_INIT_FAILED(err)) {
-        _Py_FatalInitError(err);
+        _Py_ExitInitError(err);
     }
 }
 
@@ -1432,7 +1432,7 @@ Py_NewInterpreter(void)
     PyThreadState *tstate;
     _PyInitError err = new_interpreter(&tstate);
     if (_Py_INIT_FAILED(err)) {
-        _Py_FatalInitError(err);
+        _Py_ExitInitError(err);
     }
     return tstate;
 
@@ -2073,12 +2073,17 @@ Py_FatalError(const char *msg)
 }
 
 void _Py_NO_RETURN
-_Py_FatalInitError(_PyInitError err)
+_Py_ExitInitError(_PyInitError err)
 {
-    /* On "user" error: exit with status 1.
-       For all other errors, call abort(). */
-    int status = err.user_err ? 1 : -1;
-    fatal_error(err.prefix, err.msg, status);
+    if (err.exitcode >= 0) {
+        exit(err.exitcode);
+    }
+    else {
+        /* On "user" error: exit with status 1.
+           For all other errors, call abort(). */
+        int status = err.user_err ? 1 : -1;
+        fatal_error(err.prefix, err.msg, status);
+    }
 }
 
 /* Clean up and exit */