Add PyConfig_GetInt()

* Add functions to get runtime config:

  * PyConfig_GetInt()
  * PyConfig_GetStr()
  * PyConfig_GetStrList()

* Add Modules/_testcapi/config.c
* Add test_initconfig

Author: vstinner

Include/initconfig.h

@@ -81,6 +81,29 @@ PyAPI_FUNC(char*) PyInitConfig_GetErrorMsg(PyInitConfig* config);
 // The function does not return.
 PyAPI_FUNC(void) _Py_NO_RETURN Py_ExitWithInitConfig(PyInitConfig *config);
 
+
+// Get an integer configuration option.
+// Return 0 and set '*value' on success.
+// Raise an exception return -1 on error.
+PyAPI_FUNC(int) PyConfig_GetInt(
+    const char *key,
+    int64_t *value);
+
+// Get a string configuration option.
+// Return 0 and set '*value' on success. '*value' can be set to a Python str
+// object or to None.
+// Raise an exception return -1 on error.
+PyAPI_FUNC(int) PyConfig_GetStr(
+    const char *key,
+    PyObject **value);
+
+// Get a string configuration option.
+// Return 0 and set '*value' to a Python list on success.
+// Raise an exception return -1 on error.
+PyAPI_FUNC(int) PyConfig_GetStrList(
+    const char *key,
+    PyObject **value);
+
 #endif  // !Py_LIMITED_API
 
 

Lib/test/test_initconfig.py

@@ -0,0 +1,59 @@
+"""
+Tests on PyConfig API (PEP 587).
+"""
+import os
+import sys
+import unittest
+try:
+    import _testcapi
+except ImportError:
+    _testcapi = None
+
+
+@unittest.skipIf(_testcapi is None, 'need _testcapi')
+class CAPITests(unittest.TestCase):
+    def check_get_func(self, get_func, wrong_type_key: str):
+        with self.assertRaises(TypeError):
+            get_func(wrong_type_key)
+
+        with self.assertRaisesRegex(ValueError,
+                                    'unknown config option: NONEXISTENT_KEY'):
+            get_func('NONEXISTENT_KEY')
+
+    def test_config_getint(self):
+        config_getint = _testcapi.config_getint
+        # PyConfig_MEMBER_INT type
+        self.assertEqual(config_getint('verbose'), sys.flags.verbose)
+
+        # PyConfig_MEMBER_UINT type
+        self.assertEqual(config_getint('isolated'), sys.flags.isolated)
+
+        # PyConfig_MEMBER_ULONG type
+        hash_seed = config_getint('hash_seed')
+        self.assertIsInstance(hash_seed, int)
+        self.assertGreaterEqual(hash_seed, 0)
+
+        # platlibdir is a str
+        self.check_get_func(config_getint, 'platlibdir')
+
+    def test_config_getstr(self):
+        config_getstr = _testcapi.config_getstr
+        # PyConfig_MEMBER_WSTR type
+        self.assertEqual(config_getstr('platlibdir'), sys.platlibdir)
+        if 'PYTHONDUMPREFSFILE' not in os.environ:
+            # PyConfig_MEMBER_WSTR_OPT type
+            self.assertIsNone(config_getstr('dump_refs_file'))
+
+        # verbose is an int
+        self.check_get_func(config_getstr, 'verbose')
+
+    def test_config_getstrlist(self):
+        config_getstrlist = _testcapi.config_getstrlist
+        self.assertEqual(config_getstrlist('orig_argv'), sys.orig_argv)
+
+        # verbose is an int
+        self.check_get_func(config_getstrlist, 'verbose')
+
+
+if __name__ == "__main__":
+    unittest.main()

Modules/Setup.stdlib.in

@@ -159,7 +159,7 @@
 @MODULE__XXTESTFUZZ_TRUE@_xxtestfuzz _xxtestfuzz/_xxtestfuzz.c _xxtestfuzz/fuzzer.c
 @MODULE__TESTBUFFER_TRUE@_testbuffer _testbuffer.c
 @MODULE__TESTINTERNALCAPI_TRUE@_testinternalcapi _testinternalcapi.c _testinternalcapi/test_lock.c _testinternalcapi/pytime.c
-@MODULE__TESTCAPI_TRUE@_testcapi _testcapimodule.c _testcapi/vectorcall.c _testcapi/vectorcall_limited.c _testcapi/heaptype.c _testcapi/abstract.c _testcapi/unicode.c _testcapi/dict.c _testcapi/getargs.c _testcapi/datetime.c _testcapi/docstring.c _testcapi/mem.c _testcapi/watchers.c _testcapi/long.c _testcapi/float.c _testcapi/structmember.c _testcapi/exceptions.c _testcapi/code.c _testcapi/buffer.c _testcapi/pyatomic.c _testcapi/pyos.c _testcapi/immortal.c _testcapi/heaptype_relative.c _testcapi/gc.c
+@MODULE__TESTCAPI_TRUE@_testcapi _testcapimodule.c _testcapi/vectorcall.c _testcapi/vectorcall_limited.c _testcapi/heaptype.c _testcapi/abstract.c _testcapi/unicode.c _testcapi/dict.c _testcapi/getargs.c _testcapi/datetime.c _testcapi/docstring.c _testcapi/mem.c _testcapi/watchers.c _testcapi/long.c _testcapi/float.c _testcapi/structmember.c _testcapi/exceptions.c _testcapi/code.c _testcapi/buffer.c _testcapi/pyatomic.c _testcapi/pyos.c _testcapi/immortal.c _testcapi/heaptype_relative.c _testcapi/gc.c _testcapi/config.c
 @MODULE__TESTCLINIC_TRUE@_testclinic _testclinic.c
 @MODULE__TESTCLINIC_LIMITED_TRUE@_testclinic_limited _testclinic_limited.c
 

Modules/_testcapi/clinic/config.c.h

@@ -0,0 +1,83 @@
+#define Py_LIMITED_API 0x030d0000 // 3.13
+#include "parts.h"
+
+#include "clinic/config.c.h"
+
+/*[clinic input]
+module _testcapi
+[clinic start generated code]*/
+/*[clinic end generated code: output=da39a3ee5e6b4b0d input=6361033e795369fc]*/
+
+/*[clinic input]
+_testcapi.config_getint
+
+    name: str
+    /
+[clinic start generated code]*/
+
+static PyObject *
+_testcapi_config_getint_impl(PyObject *module, const char *name)
+/*[clinic end generated code: output=25c0f293af162318 input=e432a47a41785e41]*/
+{
+    int64_t value;
+    if (PyConfig_GetInt(name, &value) < 0) {
+        return NULL;
+    }
+    Py_BUILD_ASSERT(sizeof(long long) >= sizeof(int64_t));
+    return PyLong_FromLongLong(value);
+}
+
+
+/*[clinic input]
+_testcapi.config_getstr
+
+    name: str
+    /
+[clinic start generated code]*/
+
+static PyObject *
+_testcapi_config_getstr_impl(PyObject *module, const char *name)
+/*[clinic end generated code: output=7c71c97700a6d313 input=caba5bd5f7d88b42]*/
+{
+    PyObject *value;
+    if (PyConfig_GetStr(name, &value) < 0) {
+        return NULL;
+    }
+    return value;
+}
+
+
+/*[clinic input]
+_testcapi.config_getstrlist
+
+    name: str
+    /
+[clinic start generated code]*/
+
+static PyObject *
+_testcapi_config_getstrlist_impl(PyObject *module, const char *name)
+/*[clinic end generated code: output=10dc18bbfb9981b8 input=bc9fe7319fcf9f68]*/
+{
+    PyObject *value;
+    if (PyConfig_GetStrList(name, &value) < 0) {
+        return NULL;
+    }
+    return value;
+}
+
+
+static PyMethodDef test_methods[] = {
+    _TESTCAPI_CONFIG_GETINT_METHODDEF
+    _TESTCAPI_CONFIG_GETSTR_METHODDEF
+    _TESTCAPI_CONFIG_GETSTRLIST_METHODDEF
+    {NULL}
+};
+
+int _PyTestCapi_Init_Config(PyObject *mod)
+{
+    if (PyModule_AddFunctions(mod, test_methods) < 0) {
+        return -1;
+    }
+
+    return 0;
+}

Modules/_testcapi/config.c

@@ -325,9 +325,6 @@ int _PyTestCapi_Init_GC(PyObject *mod)
     if (PyModule_AddFunctions(mod, test_methods) < 0) {
         return -1;
     }
-    if (PyModule_AddFunctions(mod, test_methods) < 0) {
-        return -1;
-    }
 
     PyObject *ObjExtraData_Type = PyType_FromModuleAndSpec(
         mod, &ObjExtraData_TypeSpec, NULL);

Modules/_testcapi/gc.c

@@ -42,8 +42,8 @@ int _PyTestCapi_Init_PyAtomic(PyObject *module);
 int _PyTestCapi_Init_PyOS(PyObject *module);
 int _PyTestCapi_Init_Immortal(PyObject *module);
 int _PyTestCapi_Init_GC(PyObject *mod);
-
 int _PyTestCapi_Init_VectorcallLimited(PyObject *module);
 int _PyTestCapi_Init_HeaptypeRelative(PyObject *module);
+int _PyTestCapi_Init_Config(PyObject *mod);
 
 #endif // Py_TESTCAPI_PARTS_H

Modules/_testcapi/parts.h

@@ -4011,6 +4011,9 @@ PyInit__testcapi(void)
     if (_PyTestCapi_Init_HeaptypeRelative(m) < 0) {
         return NULL;
     }
+    if (_PyTestCapi_Init_Config(m) < 0) {
+        return NULL;
+    }
 
     PyState_AddModule(m, &_testcapimodule);
     return m;

Modules/_testcapimodule.c

@@ -116,6 +116,7 @@
     <ClCompile Include="..\Modules\_testcapi\pyos.c" />
     <ClCompile Include="..\Modules\_testcapi\immortal.c" />
     <ClCompile Include="..\Modules\_testcapi\gc.c" />
+    <ClCompile Include="..\Modules\_testcapi\config.c" />
   </ItemGroup>
   <ItemGroup>
     <ResourceCompile Include="..\PC\python_nt.rc" />

PCbuild/_testcapi.vcxproj

@@ -75,6 +75,9 @@
     <ClCompile Include="..\Modules\_testcapi\gc.c">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="..\Modules\_testcapi\config.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ResourceCompile Include="..\PC\python_nt.rc">