gh-128911: Use PyImport_ImportModuleAttr() function (#129657)

* Replace PyImport_ImportModule() + PyObject_GetAttr() with
PyImport_ImportModuleAttr().
* Replace PyImport_ImportModule() + PyObject_GetAttrString() with
PyImport_ImportModuleAttrString().

Author: vstinner

Modules/_ctypes/callbacks.c

@@ -551,31 +551,19 @@ STDAPI DllGetClassObject(REFCLSID rclsid,
 
 longCall_CanUnloadNow(void)
 {
-PyObject*mod, *func, *result;
-longretval;
-
-mod=PyImport_ImportModule("ctypes");
-if (!mod) {
-/* OutputDebugString("Could not import ctypes"); */
-/* We assume that this error can only occur when shutting
- down, so we silently ignore it */
-PyErr_Clear();
-returnE_FAIL;
- }
-/* Other errors cannot be raised, but are printed to stderr */
-func=PyObject_GetAttrString(mod, "DllCanUnloadNow");
-Py_DECREF(mod);
+PyObject*func=PyImport_ImportModuleAttrString("ctypes",
+"DllCanUnloadNow");
 if (!func) {
  goto error;
  }
 
-result=_PyObject_CallNoArgs(func);
+PyObject*result=_PyObject_CallNoArgs(func);
 Py_DECREF(func);
 if (!result) {
  goto error;
  }
 
-retval=PyLong_AsLong(result);
+longretval=PyLong_AsLong(result);
 if (PyErr_Occurred()) {
 Py_DECREF(result);
  goto error;

Modules/_ctypes/stgdict.c

@@ -258,7 +258,7 @@ PyCStructUnionType_update_stginfo(PyObject *type, PyObject *fields, int isStruct
  }
 
 PyObject*layout_func=PyImport_ImportModuleAttrString("ctypes._layout",
-"get_layout");
+"get_layout");
 if (!layout_func) {
  goto error;
  }

Modules/_testcapi/code.c

@@ -47,7 +47,6 @@ static PyObject *
 test_code_extra(PyObject*self, PyObject*Py_UNUSED(callable))
 {
 PyObject*result=NULL;
-PyObject*test_module=NULL;
 PyObject*test_func=NULL;
 
 // Get or initialize interpreter-specific code object storage index
@@ -62,11 +61,8 @@ test_code_extra(PyObject* self, PyObject *Py_UNUSED(callable))
 
 // Get a function to test with
 // This can be any Python function. Use `test.test_misc.testfunction`.
-test_module=PyImport_ImportModule("test.test_capi.test_misc");
-if (!test_module) {
- goto finally;
- }
-test_func=PyObject_GetAttrString(test_module, "testfunction");
+test_func=PyImport_ImportModuleAttrString("test.test_capi.test_misc",
+"testfunction");
 if (!test_func) {
  goto finally;
  }
@@ -102,7 +98,6 @@ test_code_extra(PyObject* self, PyObject *Py_UNUSED(callable))
  }
 result=Py_NewRef(Py_None);
 finally:
-Py_XDECREF(test_module);
 Py_XDECREF(test_func);
 returnresult;
 }

Modules/_testcapimodule.c

@@ -1057,15 +1057,10 @@ test_pep3118_obsolete_write_locks(PyObject* self, PyObject *Py_UNUSED(ignored))
 if (ret!=-1||match==0)
  goto error;
 
-PyObject*mod_io=PyImport_ImportModule("_io");
-if (mod_io==NULL) {
-returnNULL;
- }
-
 /* bytesiobuf_getbuffer() */
-PyTypeObject*type= (PyTypeObject*)PyObject_GetAttrString(
-mod_io, "_BytesIOBuffer");
-Py_DECREF(mod_io);
+PyTypeObject*type= (PyTypeObject*)PyImport_ImportModuleAttrString(
+"_io",
+"_BytesIOBuffer");
 if (type==NULL) {
 returnNULL;
  }

Modules/main.c

@@ -314,33 +314,26 @@ pymain_start_pyrepl_no_main(void)
 staticint
 pymain_run_module(constwchar_t*modname, intset_argv0)
 {
-PyObject*module, *runpy, *runmodule, *runargs, *result;
+PyObject*module, *runmodule, *runargs, *result;
 if (PySys_Audit("cpython.run_module", "u", modname) <0) {
 returnpymain_exit_err_print();
  }
-runpy=PyImport_ImportModule("runpy");
-if (runpy==NULL) {
-fprintf(stderr, "Could not import runpy module\n");
-returnpymain_exit_err_print();
- }
-runmodule=PyObject_GetAttrString(runpy, "_run_module_as_main");
+runmodule=PyImport_ImportModuleAttrString("runpy",
+"_run_module_as_main");
 if (runmodule==NULL) {
-fprintf(stderr, "Could not access runpy._run_module_as_main\n");
-Py_DECREF(runpy);
+fprintf(stderr, "Could not import runpy._run_module_as_main\n");
 returnpymain_exit_err_print();
  }
 module=PyUnicode_FromWideChar(modname, wcslen(modname));
 if (module==NULL) {
 fprintf(stderr, "Could not convert module name to unicode\n");
-Py_DECREF(runpy);
 Py_DECREF(runmodule);
 returnpymain_exit_err_print();
  }
 runargs=PyTuple_Pack(2, module, set_argv0 ? Py_True : Py_False);
 if (runargs==NULL) {
 fprintf(stderr,
 "Could not create arguments for runpy._run_module_as_main\n");
-Py_DECREF(runpy);
 Py_DECREF(runmodule);
 Py_DECREF(module);
 returnpymain_exit_err_print();
@@ -350,7 +343,6 @@ pymain_run_module(const wchar_t *modname, int set_argv0)
 if (!result&&PyErr_Occurred() ==PyExc_KeyboardInterrupt) {
 _PyRuntime.signals.unhandled_keyboard_interrupt=1;
  }
-Py_DECREF(runpy);
 Py_DECREF(runmodule);
 Py_DECREF(module);
 Py_DECREF(runargs);
@@ -497,24 +489,22 @@ pymain_run_startup(PyConfig *config, int *exitcode)
 staticint
 pymain_run_interactive_hook(int*exitcode)
 {
-PyObject*sys, *hook, *result;
-sys=PyImport_ImportModule("sys");
-if (sys==NULL) {
- goto error;
- }
-
-hook=PyObject_GetAttrString(sys, "__interactivehook__");
-Py_DECREF(sys);
+PyObject*hook=PyImport_ImportModuleAttrString("sys",
+"__interactivehook__");
 if (hook==NULL) {
-PyErr_Clear();
-return0;
+if (PyErr_ExceptionMatches(PyExc_AttributeError)) {
+// no sys.__interactivehook__ attribute
+PyErr_Clear();
+return0;
+ }
+ goto error;
  }
 
 if (PySys_Audit("cpython.run_interactivehook", "O", hook) <0) {
  goto error;
  }
 
-result=_PyObject_CallNoArgs(hook);
+PyObject*result=_PyObject_CallNoArgs(hook);
 Py_DECREF(hook);
 if (result==NULL) {
  goto error;

Python/crossinterp.c

@@ -368,12 +368,9 @@ _convert_exc_to_TracebackException(PyObject *exc, PyObject **p_tbexc)
 PyObject*create=NULL;
 
 // This is inspired by _PyErr_Display().
-PyObject*tbmod=PyImport_ImportModule("traceback");
-if (tbmod==NULL) {
-return-1;
- }
-PyObject*tbexc_type=PyObject_GetAttrString(tbmod, "TracebackException");
-Py_DECREF(tbmod);
+PyObject*tbexc_type=PyImport_ImportModuleAttrString(
+"traceback",
+"TracebackException");
 if (tbexc_type==NULL) {
 return-1;
  }

Python/pythonrun.c

@@ -1108,22 +1108,15 @@ _PyErr_Display(PyObject *file, PyObject *unused, PyObject *value, PyObject *tb)
 intunhandled_keyboard_interrupt=_PyRuntime.signals.unhandled_keyboard_interrupt;
 
 // Try first with the stdlib traceback module
-PyObject*traceback_module=PyImport_ImportModule("traceback");
-
-if (traceback_module==NULL) {
- goto fallback;
- }
-
-PyObject*print_exception_fn=PyObject_GetAttrString(traceback_module, "_print_exception_bltin");
-
+PyObject*print_exception_fn=PyImport_ImportModuleAttrString(
+"traceback",
+"_print_exception_bltin");
 if (print_exception_fn==NULL|| !PyCallable_Check(print_exception_fn)) {
-Py_DECREF(traceback_module);
  goto fallback;
  }
 
 PyObject*result=PyObject_CallOneArg(print_exception_fn, value);
 
-Py_DECREF(traceback_module);
 Py_XDECREF(print_exception_fn);
 if (result) {
 Py_DECREF(result);
@@ -1371,27 +1364,18 @@ run_mod(mod_ty mod, PyObject *filename, PyObject *globals, PyObject *locals,
  }
 
 if (interactive_src) {
-PyObject*linecache_module=PyImport_ImportModule("linecache");
-
-if (linecache_module==NULL) {
-Py_DECREF(co);
-Py_DECREF(interactive_filename);
-returnNULL;
- }
-
-PyObject*print_tb_func=PyObject_GetAttrString(linecache_module, "_register_code");
-
+PyObject*print_tb_func=PyImport_ImportModuleAttrString(
+"linecache",
+"_register_code");
 if (print_tb_func==NULL) {
 Py_DECREF(co);
 Py_DECREF(interactive_filename);
-Py_DECREF(linecache_module);
 returnNULL;
  }
 
 if (!PyCallable_Check(print_tb_func)) {
 Py_DECREF(co);
 Py_DECREF(interactive_filename);
-Py_DECREF(linecache_module);
 Py_DECREF(print_tb_func);
 PyErr_SetString(PyExc_ValueError, "linecache._register_code is not callable");
 returnNULL;
@@ -1406,7 +1390,6 @@ run_mod(mod_ty mod, PyObject *filename, PyObject *globals, PyObject *locals,
 
 Py_DECREF(interactive_filename);
 
-Py_DECREF(linecache_module);
 Py_XDECREF(print_tb_func);
 Py_XDECREF(result);
 if (!result) {