bpo-36471: Add _Py_RunMain() (GH-12618)

* Add config_read_cmdline() subfunction. Remove _PyCmdline structure.
* _PyCoreConfig_Read() now also parses config->argv command line
  arguments

Include/cpython/pylifecycle.h

@@ -41,6 +41,9 @@ PyAPI_FUNC(_PyInitError) _Py_InitializeFromWideArgs(
     int argc,
     wchar_t **argv);
 
+PyAPI_FUNC(int) _Py_RunMain(void);
+
+
 PyAPI_FUNC(void) _Py_NO_RETURN _Py_ExitInitError(_PyInitError err);
 
 /* Py_PyAtExit is for the atexit module, Py_AtExit is for low-level

Lib/test/test_embed.py

@@ -53,7 +53,12 @@ class EmbeddingTestsMixin:
                              stderr=subprocess.PIPE,
                              universal_newlines=True,
                              env=env)
-        (out, err) = p.communicate()
+        try:
+            (out, err) = p.communicate()
+        except:
+            p.terminate()
+            p.wait()
+            raise
         if p.returncode != 0 and support.verbose:
             print(f"--- {cmd} failed ---")
             print(f"stdout:\n{out}")
@@ -254,6 +259,11 @@ class EmbeddingTests(EmbeddingTestsMixin, unittest.TestCase):
         self.assertEqual(out.rstrip(), "Py_Main() after Py_Initialize: sys.argv=['-c', 'arg2']")
         self.assertEqual(err, '')
 
+    def test_run_main(self):
+        out, err = self.run_embedded_interpreter("run_main")
+        self.assertEqual(out.rstrip(), "_Py_RunMain(): sys.argv=['-c', 'arg2']")
+        self.assertEqual(err, '')
+
 
 class InitConfigTests(EmbeddingTestsMixin, unittest.TestCase):
     maxDiff = 4096
@@ -549,10 +559,11 @@ class InitConfigTests(EmbeddingTestsMixin, unittest.TestCase):
 
             'pycache_prefix': 'conf_pycache_prefix',
             'program_name': './conf_program_name',
-            'argv': ['-c', 'pass'],
+            'argv': ['-c', 'arg2'],
             'program': 'conf_program',
             'xoptions': ['core_xoption1=3', 'core_xoption2=', 'core_xoption3'],
             'warnoptions': ['error::ResourceWarning', 'default::BytesWarning'],
+            'run_command': 'pass\n',
 
             'site_import': 0,
             'bytes_warning': 1,

Modules/main.c

@@ -567,20 +567,22 @@ exit_sigint(void)
 }
 
 
-static int
-pymain_main(_PyArgv *args)
+static void _Py_NO_RETURN
+pymain_exit_error(_PyInitError err)
 {
-    _PyInitError err;
+    pymain_free();
+    _Py_ExitInitError(err);
+}
 
-    err = pymain_init(args);
-    if (_Py_INIT_FAILED(err)) {
-        goto exit_init_error;
-    }
 
+int
+_Py_RunMain(void)
+{
     int exitcode = 0;
-    err = pymain_run_python(&exitcode);
+
+    _PyInitError err = pymain_run_python(&exitcode);
     if (_Py_INIT_FAILED(err)) {
-        goto exit_init_error;
+        pymain_exit_error(err);
     }
 
     if (Py_FinalizeEx() < 0) {
@@ -596,10 +598,18 @@ pymain_main(_PyArgv *args)
     }
 
     return exitcode;
+}
 
-exit_init_error:
-    pymain_free();
-    _Py_ExitInitError(err);
+
+static int
+pymain_main(_PyArgv *args)
+{
+    _PyInitError err = pymain_init(args);
+    if (_Py_INIT_FAILED(err)) {
+        pymain_exit_error(err);
+    }
+
+    return _Py_RunMain();
 }
 
 

Programs/_testembed.c

@@ -447,9 +447,11 @@ static int test_init_from_config(void)
     Py_SetProgramName(L"./globalvar");
     config.program_name = L"./conf_program_name";
 
-    static wchar_t* argv[2] = {
+    static wchar_t* argv[] = {
+        L"python3",
         L"-c",
         L"pass",
+        L"arg2",
     };
     config.argv.length = Py_ARRAY_LENGTH(argv);
     config.argv.items = argv;
@@ -528,7 +530,6 @@ static int test_init_from_config(void)
     config._frozen = 1;
 
     err = _Py_InitializeFromConfig(&config);
-    /* Don't call _PyCoreConfig_Clear() since all strings are static */
     if (_Py_INIT_FAILED(err)) {
         _Py_ExitInitError(err);
     }
@@ -712,6 +713,27 @@ static int test_init_dev_mode(void)
 }
 
 
+static int test_run_main(void)
+{
+    _PyCoreConfig config = _PyCoreConfig_INIT;
+
+    wchar_t *argv[] = {L"python3", L"-c",
+                       (L"import sys; "
+                        L"print(f'_Py_RunMain(): sys.argv={sys.argv}')"),
+                       L"arg2"};
+    config.argv.length = Py_ARRAY_LENGTH(argv);
+    config.argv.items = argv;
+    config.program_name = L"./python3";
+
+    _PyInitError err = _Py_InitializeFromConfig(&config);
+    if (_Py_INIT_FAILED(err)) {
+        _Py_ExitInitError(err);
+    }
+
+    return _Py_RunMain();
+}
+
+
 /* *********************************************************
  * List of test cases and the function that implements it.
  *
@@ -748,6 +770,7 @@ static struct TestCase TestCases[] = {
     { "init_isolated", test_init_isolated },
     { "preinit_isolated1", test_preinit_isolated1 },
     { "preinit_isolated2", test_preinit_isolated2 },
+    { "run_main", test_run_main },
     { NULL, NULL }
 };