bpo-1635741: Port mmap module to multiphase initialization (GH-19459)

Author: corona10

Misc/NEWS.d/next/Core and Builtins/2020-04-10-23-54-57.bpo-1635741.ZURqoN.rst

@@ -0,0 +1 @@
+Port :mod:`mmap` to multiphase initialization.

Modules/mmapmodule.c

@@ -1509,157 +1509,163 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
 }
 #endif /* MS_WINDOWS */
 
-static void
-setint(PyObject *d, const char *name, long value)
+static int
+mmap_exec(PyObject *module)
 {
-    PyObject *o = PyLong_FromLong(value);
-    if (o) {
-        PyDict_SetItemString(d, name, o);
-        Py_DECREF(o);
+    if (PyType_Ready(&mmap_object_type) < 0) {
+        return -1;
     }
-}
-
 
-static struct PyModuleDef mmapmodule = {
-    PyModuleDef_HEAD_INIT,
-    "mmap",
-    NULL,
-    -1,
-    NULL,
-    NULL,
-    NULL,
-    NULL,
-    NULL
-};
-
-PyMODINIT_FUNC
-PyInit_mmap(void)
-{
-    PyObject *dict, *module;
+    Py_INCREF(PyExc_OSError);
+    if (PyModule_AddObject(module, "error", PyExc_OSError) < 0) {
+        Py_DECREF(PyExc_OSError);
+        return -1;
+    }
+    if (PyModule_AddType(module, &mmap_object_type) < 0) {
+        return -1;
+    }
 
-    if (PyType_Ready(&mmap_object_type) < 0)
-        return NULL;
+#define ADD_INT_MACRO(module, constant)                                     \
+    do {                                                                    \
+        if (PyModule_AddIntConstant(module, #constant, constant) < 0) {     \
+            return -1;                                                      \
+        }                                                                   \
+    } while (0)
 
-    module = PyModule_Create(&mmapmodule);
-    if (module == NULL)
-        return NULL;
-    dict = PyModule_GetDict(module);
-    if (!dict)
-        return NULL;
-    PyDict_SetItemString(dict, "error", PyExc_OSError);
-    PyDict_SetItemString(dict, "mmap", (PyObject*) &mmap_object_type);
 #ifdef PROT_EXEC
-    setint(dict, "PROT_EXEC", PROT_EXEC);
+    ADD_INT_MACRO(module, PROT_EXEC);
 #endif
 #ifdef PROT_READ
-    setint(dict, "PROT_READ", PROT_READ);
+    ADD_INT_MACRO(module, PROT_READ);
 #endif
 #ifdef PROT_WRITE
-    setint(dict, "PROT_WRITE", PROT_WRITE);
+    ADD_INT_MACRO(module, PROT_WRITE);
 #endif
 
 #ifdef MAP_SHARED
-    setint(dict, "MAP_SHARED", MAP_SHARED);
+    ADD_INT_MACRO(module, MAP_SHARED);
 #endif
 #ifdef MAP_PRIVATE
-    setint(dict, "MAP_PRIVATE", MAP_PRIVATE);
+    ADD_INT_MACRO(module, MAP_PRIVATE);
 #endif
 #ifdef MAP_DENYWRITE
-    setint(dict, "MAP_DENYWRITE", MAP_DENYWRITE);
+    ADD_INT_MACRO(module, MAP_DENYWRITE);
 #endif
 #ifdef MAP_EXECUTABLE
-    setint(dict, "MAP_EXECUTABLE", MAP_EXECUTABLE);
+    ADD_INT_MACRO(module, MAP_EXECUTABLE);
 #endif
 #ifdef MAP_ANONYMOUS
-    setint(dict, "MAP_ANON", MAP_ANONYMOUS);
-    setint(dict, "MAP_ANONYMOUS", MAP_ANONYMOUS);
+    if (PyModule_AddIntConstant(module, "MAP_ANON", MAP_ANONYMOUS) < 0 ) {
+        return -1;
+    }
+    ADD_INT_MACRO(module, MAP_ANONYMOUS);
 #endif
 #ifdef MAP_POPULATE
-    setint(dict, "MAP_POPULATE", MAP_POPULATE);
+    ADD_INT_MACRO(module, MAP_POPULATE);
 #endif
+    if (PyModule_AddIntConstant(module, "PAGESIZE", (long)my_getpagesize()) < 0 ) {
+        return -1;
+    }
 
-    setint(dict, "PAGESIZE", (long)my_getpagesize());
-
-    setint(dict, "ALLOCATIONGRANULARITY", (long)my_getallocationgranularity());
+    if (PyModule_AddIntConstant(module, "ALLOCATIONGRANULARITY", (long)my_getallocationgranularity()) < 0 ) {
+        return -1;
+    }
 
-    setint(dict, "ACCESS_DEFAULT", ACCESS_DEFAULT);
-    setint(dict, "ACCESS_READ", ACCESS_READ);
-    setint(dict, "ACCESS_WRITE", ACCESS_WRITE);
-    setint(dict, "ACCESS_COPY", ACCESS_COPY);
+    ADD_INT_MACRO(module, ACCESS_DEFAULT);
+    ADD_INT_MACRO(module, ACCESS_READ);
+    ADD_INT_MACRO(module, ACCESS_WRITE);
+    ADD_INT_MACRO(module, ACCESS_COPY);
 
 #ifdef HAVE_MADVISE
     // Conventional advice values
 #ifdef MADV_NORMAL
-    setint(dict, "MADV_NORMAL", MADV_NORMAL);
+    ADD_INT_MACRO(module, MADV_NORMAL);
 #endif
 #ifdef MADV_RANDOM
-    setint(dict, "MADV_RANDOM", MADV_RANDOM);
+    ADD_INT_MACRO(module, MADV_RANDOM);
 #endif
 #ifdef MADV_SEQUENTIAL
-    setint(dict, "MADV_SEQUENTIAL", MADV_SEQUENTIAL);
+    ADD_INT_MACRO(module, MADV_SEQUENTIAL);
 #endif
 #ifdef MADV_WILLNEED
-    setint(dict, "MADV_WILLNEED", MADV_WILLNEED);
+    ADD_INT_MACRO(module, MADV_WILLNEED);
 #endif
 #ifdef MADV_DONTNEED
-    setint(dict, "MADV_DONTNEED", MADV_DONTNEED);
+    ADD_INT_MACRO(module, MADV_DONTNEED);
 #endif
 
     // Linux-specific advice values
 #ifdef MADV_REMOVE
-    setint(dict, "MADV_REMOVE", MADV_REMOVE);
+    ADD_INT_MACRO(module, MADV_REMOVE);
 #endif
 #ifdef MADV_DONTFORK
-    setint(dict, "MADV_DONTFORK", MADV_DONTFORK);
+    ADD_INT_MACRO(module, MADV_DONTFORK);
 #endif
 #ifdef MADV_DOFORK
-    setint(dict, "MADV_DOFORK", MADV_DOFORK);
+    ADD_INT_MACRO(module, MADV_DOFORK);
 #endif
 #ifdef MADV_HWPOISON
-    setint(dict, "MADV_HWPOISON", MADV_HWPOISON);
+    ADD_INT_MACRO(module, MADV_HWPOISON);
 #endif
 #ifdef MADV_MERGEABLE
-    setint(dict, "MADV_MERGEABLE", MADV_MERGEABLE);
+    ADD_INT_MACRO(module, MADV_MERGEABLE);
 #endif
 #ifdef MADV_UNMERGEABLE
-    setint(dict, "MADV_UNMERGEABLE", MADV_UNMERGEABLE);
+    ADD_INT_MACRO(module, MADV_UNMERGEABLE);
 #endif
 #ifdef MADV_SOFT_OFFLINE
-    setint(dict, "MADV_SOFT_OFFLINE", MADV_SOFT_OFFLINE);
+    ADD_INT_MACRO(module, MADV_SOFT_OFFLINE);
 #endif
 #ifdef MADV_HUGEPAGE
-    setint(dict, "MADV_HUGEPAGE", MADV_HUGEPAGE);
+    ADD_INT_MACRO(module, MADV_HUGEPAGE);
 #endif
 #ifdef MADV_NOHUGEPAGE
-    setint(dict, "MADV_NOHUGEPAGE", MADV_NOHUGEPAGE);
+    ADD_INT_MACRO(module, MADV_NOHUGEPAGE);
 #endif
 #ifdef MADV_DONTDUMP
-    setint(dict, "MADV_DONTDUMP", MADV_DONTDUMP);
+    ADD_INT_MACRO(module, MADV_DONTDUMP);
 #endif
 #ifdef MADV_DODUMP
-    setint(dict, "MADV_DODUMP", MADV_DODUMP);
+    ADD_INT_MACRO(module, MADV_DODUMP);
 #endif
 #ifdef MADV_FREE // (Also present on FreeBSD and macOS.)
-    setint(dict, "MADV_FREE", MADV_FREE);
+    ADD_INT_MACRO(module, MADV_FREE);
 #endif
 
     // FreeBSD-specific
 #ifdef MADV_NOSYNC
-    setint(dict, "MADV_NOSYNC", MADV_NOSYNC);
+    ADD_INT_MACRO(module, MADV_NOSYNC);
 #endif
 #ifdef MADV_AUTOSYNC
-    setint(dict, "MADV_AUTOSYNC", MADV_AUTOSYNC);
+    ADD_INT_MACRO(module, MADV_AUTOSYNC);
 #endif
 #ifdef MADV_NOCORE
-    setint(dict, "MADV_NOCORE", MADV_NOCORE);
+    ADD_INT_MACRO(module, MADV_NOCORE);
 #endif
 #ifdef MADV_CORE
-    setint(dict, "MADV_CORE", MADV_CORE);
+    ADD_INT_MACRO(module, MADV_CORE);
 #endif
 #ifdef MADV_PROTECT
-    setint(dict, "MADV_PROTECT", MADV_PROTECT);
+    ADD_INT_MACRO(module, MADV_PROTECT);
 #endif
 #endif // HAVE_MADVISE
+    return 0;
+}
 
-    return module;
+static PyModuleDef_Slot mmap_slots[] = {
+    {Py_mod_exec, mmap_exec},
+    {0, NULL}
+};
+
+static struct PyModuleDef mmapmodule = {
+    PyModuleDef_HEAD_INIT,
+    .m_name = "mmap",
+    .m_size = 0,
+    .m_slots = mmap_slots,
+};
+
+PyMODINIT_FUNC
+PyInit_mmap(void)
+{
+    return PyModuleDef_Init(&mmapmodule);
 }