bpo-35239: _PySys_EndInit() copies module_search_path (GH-10532)

miss-islington · vstinner · web-flow · commit d2be9a5c1322 · 2018-11-16T03:34:35.000-08:00
* The _PySys_EndInit() function now copies the config->module_search_path list, so config is longer modified when sys.path is updated. * config->warnoptions list and config->xoptions dict are also copied * test_embed: InitConfigTests now also tests main_config['module_search_path'] * Fix _Py_InitializeMainInterpreter(): don't use config->warnoptions but sys.warnoptions to decide if the warnings module should be imported at startup. (cherry picked from commit 37cd982) Co-authored-by: Victor Stinner <vstinner@redhat.com>
diff --git a/Lib/test/test_embed.py b/Lib/test/test_embed.py
@@ -301,10 +301,6 @@ class InitConfigTests(EmbeddingTestsMixin, unittest.TestCase):
     }
 
     # main config
-    UNTESTED_MAIN_CONFIG = (
-        # FIXME: untested main configuration variables
-        'module_search_path',
-    )
     COPY_MAIN_CONFIG = (
         # Copy core config to main config for expected values
         'argv',
@@ -315,7 +311,8 @@ class InitConfigTests(EmbeddingTestsMixin, unittest.TestCase):
         'install_signal_handlers',
         'prefix',
         'warnoptions',
-        # xoptions is created from core_config in check_main_config()
+        # xoptions is created from core_config in check_main_config().
+        # 'module_search_paths' is copied to 'module_search_path'.
     )
 
     # global config
@@ -389,12 +386,10 @@ def check_main_config(self, config):
         main_config = config['main_config']
 
         # main config
-        for key in self.UNTESTED_MAIN_CONFIG:
-            del main_config[key]
-
         expected_main = {}
         for key in self.COPY_MAIN_CONFIG:
             expected_main[key] = core_config[key]
+        expected_main['module_search_path'] = core_config['module_search_paths']
         expected_main['xoptions'] = self.main_xoptions(core_config['xoptions'])
         self.assertEqual(main_config, expected_main)
 
diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
@@ -967,8 +967,8 @@ _Py_InitializeMainInterpreter(PyInterpreterState *interp,
     }
 
     /* Initialize warnings. */
-    if (interp->config.warnoptions != NULL &&
-        PyList_Size(interp->config.warnoptions) > 0)
+    PyObject *warnoptions = PySys_GetObject("warnoptions");
+    if (warnoptions != NULL && PyList_Size(warnoptions) > 0)
     {
         PyObject *warnings_module = PyImport_ImportModule("warnings");
         if (warnings_module == NULL) {
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
@@ -2464,7 +2464,20 @@ _PySys_EndInit(PyObject *sysdict, _PyMainInterpreterConfig *config)
     assert(config->exec_prefix != NULL);
     assert(config->base_exec_prefix != NULL);
 
-    SET_SYS_FROM_STRING_BORROW("path", config->module_search_path);
+#define COPY_LIST(KEY, ATTR) \
+    do { \
+        assert(PyList_Check(config->ATTR)); \
+        PyObject *list = PyList_GetSlice(config->ATTR, \
+                                         0, PyList_GET_SIZE(config->ATTR)); \
+        if (list == NULL) { \
+            return -1; \
+        } \
+        SET_SYS_FROM_STRING_BORROW(KEY, list); \
+        Py_DECREF(list); \
+    } while (0)
+
+    COPY_LIST("path", module_search_path);
+
     SET_SYS_FROM_STRING_BORROW("executable", config->executable);
     SET_SYS_FROM_STRING_BORROW("prefix", config->prefix);
     SET_SYS_FROM_STRING_BORROW("base_prefix", config->base_prefix);
@@ -2475,12 +2488,19 @@ _PySys_EndInit(PyObject *sysdict, _PyMainInterpreterConfig *config)
         SET_SYS_FROM_STRING_BORROW("argv", config->argv);
     }
     if (config->warnoptions != NULL) {
-        SET_SYS_FROM_STRING_BORROW("warnoptions", config->warnoptions);
+        COPY_LIST("warnoptions", warnoptions);
     }
     if (config->xoptions != NULL) {
-        SET_SYS_FROM_STRING_BORROW("_xoptions", config->xoptions);
+        PyObject *dict = PyDict_Copy(config->xoptions);
+        if (dict == NULL) {
+            return -1;
+        }
+        SET_SYS_FROM_STRING_BORROW("_xoptions", dict);
+        Py_DECREF(dict);
     }
 
+#undef COPY_LIST
+
     /* Set flags to their final values */
     SET_SYS_FROM_STRING_INT_RESULT("flags", make_flags());
     /* prevent user from creating new instances */

Original file line number	Diff line number	Diff line change
`@@ -967,8 +967,8 @@ _Py_InitializeMainInterpreter(PyInterpreterState *interp,`
`967`	`967`	`}`
`968`	`968`
`969`	`969`	`/* Initialize warnings. */`
`970`		`- if (interp->config.warnoptions != NULL &&`
`971`		`- PyList_Size(interp->config.warnoptions) > 0)`
	`970`	`+ PyObject *warnoptions = PySys_GetObject("warnoptions");`
	`971`	`+ if (warnoptions != NULL && PyList_Size(warnoptions) > 0)`
`972`	`972`	`{`
`973`	`973`	`PyObject *warnings_module = PyImport_ImportModule("warnings");`
`974`	`974`	`if (warnings_module == NULL) {`