python · matrixise · Mar 18, 2019 · Mar 18, 2019 · Mar 19, 2019 · Mar 19, 2019
diff --git a/Doc/c-api/structures.rst b/Doc/c-api/structures.rst
@@ -290,11 +290,11 @@ definition with the same method name.
   handles use of the :keyword:`del` statement on that attribute more correctly
   than :c:macro:`T_OBJECT`.

-   :attr:`flags` can be ``0`` for write and read access or :c:macro:`READONLY` for
-   read-only access.  Using :c:macro:`T_STRING` for :attr:`type` implies
-   :c:macro:`READONLY`.  :c:macro:`T_STRING` data is interpreted as UTF-8.
-   Only :c:macro:`T_OBJECT` and :c:macro:`T_OBJECT_EX`
-   members can be deleted.  (They are set to *NULL*).
+   :attr:`flags` can be ``0`` for write and read access (also represented by the
+   :c:macro:`PY_READWRITE`) or :c:macro:`PY_READONLY` for read-only access.  Using
+   :c:macro:`T_STRING` for :attr:`type` implies :c:macro:`PY_READONLY`.
+   :c:macro:`T_STRING` data is interpreted as UTF-8.  Only :c:macro:`T_OBJECT`
+   and :c:macro:`T_OBJECT_EX` members can be deleted.  (They are set to *NULL*).


 .. c:type:: PyGetSetDef

diff --git a/Doc/extending/newtypes.rst b/Doc/extending/newtypes.rst
@@ -282,23 +282,26 @@ store flags which control how the attribute can be accessed.
 The following flag constants are defined in :file:`structmember.h`; they may be
 combined using bitwise-OR.

-+---------------------------+----------------------------------------------+
-| Constant                  | Meaning                                      |
-+===========================+==============================================+
-| :const:`READONLY`         | Never writable.                              |
-+---------------------------+----------------------------------------------+
-| :const:`READ_RESTRICTED`  | Not readable in restricted mode.             |
-+---------------------------+----------------------------------------------+
-| :const:`WRITE_RESTRICTED` | Not writable in restricted mode.             |
-+---------------------------+----------------------------------------------+
-| :const:`RESTRICTED`       | Not readable or writable in restricted mode. |
-+---------------------------+----------------------------------------------+
+------------------------------+----------------------------------------------+---------------------------+
+| Constant                     | Meaning                                      | Former Constant           |
+==============================+==============================================+===========================+
+| :const:`PY_READWRITE`        | Writable.                                    | 0                         |
+------------------------------+----------------------------------------------+---------------------------+
+| :const:`PY_READONLY`         | Never writable.                              | :const:`READONLY`         |
+------------------------------+----------------------------------------------+---------------------------+
+| :const:`PY_READ_RESTRICTED`  | Not readable in restricted mode.             | :const:`READ_RESTRICTED`  |
+------------------------------+----------------------------------------------+---------------------------+
+| :const:`PY_WRITE_RESTRICTED` | Not writable in restricted mode.             | :const:`WRITE_RESTRICTED` |
+------------------------------+----------------------------------------------+---------------------------+
+| :const:`PY_RESTRICTED`       | Not readable or writable in restricted mode. | :const:`RESTRICTED`       |
+------------------------------+----------------------------------------------+---------------------------+

 .. index::
-   single: READONLY
-   single: READ_RESTRICTED
-   single: WRITE_RESTRICTED
-   single: RESTRICTED
+   single: PY_READWRITE
+   single: PY_READONLY
+   single: PY_READ_RESTRICTED
+   single: PY_WRITE_RESTRICTED
+   single: PY_RESTRICTED

 An interesting advantage of using the :c:member:`~PyTypeObject.tp_members` table to build
 descriptors that are used at runtime is that any attribute defined this way can

diff --git a/Doc/extending/newtypes_tutorial.rst b/Doc/extending/newtypes_tutorial.rst
@@ -429,11 +429,11 @@ We want to expose our instance variables as attributes. There are a
 number of ways to do that. The simplest way is to define member definitions::

   static PyMemberDef Custom_members[] = {
-       {"first", T_OBJECT_EX, offsetof(CustomObject, first), 0,
+       {"first", T_OBJECT_EX, offsetof(CustomObject, first), PY_READWRITE,
        "first name"},
-       {"last", T_OBJECT_EX, offsetof(CustomObject, last), 0,
+       {"last", T_OBJECT_EX, offsetof(CustomObject, last), PY_READWRITE,
        "last name"},
-       {"number", T_INT, offsetof(CustomObject, number), 0,
+       {"number", T_INT, offsetof(CustomObject, number), PY_READWRITE,
        "custom number"},
       {NULL}  /* Sentinel */
   };
@@ -602,7 +602,7 @@ above.  In this case, we aren't using a closure, so we just pass *NULL*.
 We also remove the member definitions for these attributes::

   static PyMemberDef Custom_members[] = {
-       {"number", T_INT, offsetof(CustomObject, number), 0,
+       {"number", T_INT, offsetof(CustomObject, number), PY_READWRITE,
        "custom number"},
       {NULL}  /* Sentinel */
   };

diff --git a/Doc/includes/custom2.c b/Doc/includes/custom2.c
@@ -64,11 +64,11 @@ Custom_init(CustomObject *self, PyObject *args, PyObject *kwds)
 }

 static PyMemberDef Custom_members[] = {
-    {"first", T_OBJECT_EX, offsetof(CustomObject, first), 0,
+    {"first", T_OBJECT_EX, offsetof(CustomObject, first), PY_READWRITE,
     "first name"},
-    {"last", T_OBJECT_EX, offsetof(CustomObject, last), 0,
+    {"last", T_OBJECT_EX, offsetof(CustomObject, last), PY_READWRITE,
     "last name"},
-    {"number", T_INT, offsetof(CustomObject, number), 0,
+    {"number", T_INT, offsetof(CustomObject, number), PY_READWRITE,
     "custom number"},
    {NULL}  /* Sentinel */
 };

diff --git a/Doc/includes/custom3.c b/Doc/includes/custom3.c
@@ -64,7 +64,7 @@ Custom_init(CustomObject *self, PyObject *args, PyObject *kwds)
 }

 static PyMemberDef Custom_members[] = {
-    {"number", T_INT, offsetof(CustomObject, number), 0,
+    {"number", T_INT, offsetof(CustomObject, number), PY_READWRITE,
     "custom number"},
    {NULL}  /* Sentinel */
 };

diff --git a/Doc/includes/custom4.c b/Doc/includes/custom4.c
@@ -80,7 +80,7 @@ Custom_init(CustomObject *self, PyObject *args, PyObject *kwds)
 }

 static PyMemberDef Custom_members[] = {
-    {"number", T_INT, offsetof(CustomObject, number), 0,
+    {"number", T_INT, offsetof(CustomObject, number), PY_READWRITE,
     "custom number"},
    {NULL}  /* Sentinel */
 };

diff --git a/Include/structmember.h b/Include/structmember.h
@@ -11,7 +11,7 @@ extern "C" {

 /* An array of PyMemberDef structures defines the name, type and offset
   of selected members of a C structure.  These can be read by
-   PyMember_GetOne() and set by PyMember_SetOne() (except if their READONLY
+   PyMember_GetOne() and set by PyMember_SetOne() (except if their PY_READONLY
   flag is set).  The array must be terminated with an entry whose name
   pointer is NULL. */

@@ -57,10 +57,17 @@ typedef struct PyMemberDef {


 /* Flags */
-#define READONLY            1
-#define READ_RESTRICTED     2
-#define PY_WRITE_RESTRICTED 4
-#define RESTRICTED          (READ_RESTRICTED | PY_WRITE_RESTRICTED)
+#define PY_READWRITE            0
+#define PY_READONLY             1
+#define PY_READ_RESTRICTED      2
+#define PY_WRITE_RESTRICTED     4
+#define PY_RESTRICTED           (PY_READ_RESTRICTED | PY_WRITE_RESTRICTED)
+
+/* Flags defined for the backward compatibility */
+#define READWRITE               PY_READWRITE
+#define READONLY                PY_READONLY
+#define READ_RESTRICTED         PY_READ_RESTRICTED
+#define RESTRICTED              PY_RESTRICTED


 /* Current API, use this */

diff --git a/Misc/NEWS.d/next/Core and Builtins/2019-03-18-15-44-50.bpo-36347.tpMZfJ.rst b/Misc/NEWS.d/next/Core and Builtins/2019-03-18-15-44-50.bpo-36347.tpMZfJ.rst
@@ -0,0 +1,3 @@
+Add :c:macro:`PY_READWRITE` for a more explicit definition of the
+:c:type:`PyMemberDef` members and add the prefix ``PY_`` to these constants.
+Contributed by Stéphane Wirtel.
diff --git a/Modules/_bz2module.c b/Modules/_bz2module.c
@@ -676,10 +676,10 @@ PyDoc_STRVAR(BZ2Decompressor_needs_input_doc,

 static PyMemberDef BZ2Decompressor_members[] = {
    {"eof", T_BOOL, offsetof(BZ2Decompressor, eof),
-     READONLY, BZ2Decompressor_eof__doc__},
+     PY_READONLY, BZ2Decompressor_eof__doc__},
    {"unused_data", T_OBJECT_EX, offsetof(BZ2Decompressor, unused_data),
-     READONLY, BZ2Decompressor_unused_data__doc__},
-    {"needs_input", T_BOOL, offsetof(BZ2Decompressor, needs_input), READONLY,
+     PY_READONLY, BZ2Decompressor_unused_data__doc__},
+    {"needs_input", T_BOOL, offsetof(BZ2Decompressor, needs_input), PY_READONLY,
     BZ2Decompressor_needs_input_doc},
    {NULL}
 };

diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c
@@ -2072,7 +2072,7 @@ static PyMethodDef defdict_methods[] = {

 static PyMemberDef defdict_members[] = {
    {"default_factory", T_OBJECT,
-     offsetof(defdictobject, default_factory), 0,
+     offsetof(defdictobject, default_factory), PY_READWRITE,
     PyDoc_STR("Factory for default value called by __missing__().")},
    {NULL}
 };
@@ -2448,7 +2448,7 @@ tuplegetter_reduce(_tuplegetterobject *self, PyObject *Py_UNUSED(ignored))


 static PyMemberDef tuplegetter_members[] = {
-    {"__doc__",  T_OBJECT, offsetof(_tuplegetterobject, doc), 0},
+    {"__doc__",  T_OBJECT, offsetof(_tuplegetterobject, doc), PY_READWRITE},
    {0}
 };


diff --git a/Modules/_csv.c b/Modules/_csv.c
@@ -293,9 +293,9 @@ dialect_check_quoting(int quoting)
 #define D_OFF(x) offsetof(DialectObj, x)

 static struct PyMemberDef Dialect_memberlist[] = {
-    { "skipinitialspace",   T_BOOL, D_OFF(skipinitialspace), READONLY },
-    { "doublequote",        T_BOOL, D_OFF(doublequote), READONLY },
-    { "strict",             T_BOOL, D_OFF(strict), READONLY },
+    { "skipinitialspace",   T_BOOL, D_OFF(skipinitialspace), PY_READONLY },
+    { "doublequote",        T_BOOL, D_OFF(doublequote), PY_READONLY },
+    { "strict",             T_BOOL, D_OFF(strict), PY_READONLY },
    { NULL }
 };

@@ -889,8 +889,8 @@ static struct PyMethodDef Reader_methods[] = {
 #define R_OFF(x) offsetof(ReaderObj, x)

 static struct PyMemberDef Reader_memberlist[] = {
-    { "dialect", T_OBJECT, R_OFF(dialect), READONLY },
-    { "line_num", T_ULONG, R_OFF(line_num), READONLY },
+    { "dialect", T_OBJECT, R_OFF(dialect), PY_READONLY },
+    { "line_num", T_ULONG, R_OFF(line_num), PY_READONLY },
    { NULL }
 };

@@ -1285,7 +1285,7 @@ static struct PyMethodDef Writer_methods[] = {
 #define W_OFF(x) offsetof(WriterObj, x)

 static struct PyMemberDef Writer_memberlist[] = {
-    { "dialect", T_OBJECT, W_OFF(dialect), READONLY },
+    { "dialect", T_OBJECT, W_OFF(dialect), PY_READONLY },
    { NULL }
 };


diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
@@ -2666,13 +2666,13 @@ PyCData_dealloc(PyObject *self)

 static PyMemberDef PyCData_members[] = {
    { "_b_base_", T_OBJECT,
-      offsetof(CDataObject, b_base), READONLY,
+      offsetof(CDataObject, b_base), PY_READONLY,
      "the base object" },
    { "_b_needsfree_", T_INT,
-      offsetof(CDataObject, b_needsfree), READONLY,
+      offsetof(CDataObject, b_needsfree), PY_READONLY,
      "whether the object owns the memory or not" },
    { "_objects", T_OBJECT,
-      offsetof(CDataObject, b_objects), READONLY,
+      offsetof(CDataObject, b_objects), PY_READONLY,
      "internal objects tree (NEVER CHANGE THIS OBJECT!)"},
    { NULL },
 };

diff --git a/Modules/_ctypes/callproc.c b/Modules/_ctypes/callproc.c
@@ -544,7 +544,7 @@ PyCArg_repr(PyCArgObject *self)

 static PyMemberDef PyCArgType_members[] = {
    { "_obj", T_OBJECT,
-      offsetof(PyCArgObject, obj), READONLY,
+      offsetof(PyCArgObject, obj), PY_READONLY,
      "the wrapped object" },
    { NULL },
 };

diff --git a/Modules/_datetimemodule.c b/Modules/_datetimemodule.c
@@ -2650,13 +2650,13 @@ delta_reduce(PyDateTime_Delta* self, PyObject *Py_UNUSED(ignored))

 static PyMemberDef delta_members[] = {

-    {"days",         T_INT, OFFSET(days),         READONLY,
+    {"days",         T_INT, OFFSET(days),         PY_READONLY,
     PyDoc_STR("Number of days.")},

-    {"seconds",      T_INT, OFFSET(seconds),      READONLY,
+    {"seconds",      T_INT, OFFSET(seconds),      PY_READONLY,
     PyDoc_STR("Number of seconds (>= 0 and less than 1 day).")},

-    {"microseconds", T_INT, OFFSET(microseconds), READONLY,
+    {"microseconds", T_INT, OFFSET(microseconds), PY_READONLY,
     PyDoc_STR("Number of microseconds (>= 0 and less than 1 second).")},
    {NULL}
 };

diff --git a/Modules/_elementtree.c b/Modules/_elementtree.c
@@ -3753,8 +3753,8 @@ _elementtree_XMLParser__setevents_impl(XMLParserObject *self,
 }

 static PyMemberDef xmlparser_members[] = {
-    {"entity", T_OBJECT, offsetof(XMLParserObject, entity), READONLY, NULL},
-    {"target", T_OBJECT, offsetof(XMLParserObject, target), READONLY, NULL},
+    {"entity", T_OBJECT, offsetof(XMLParserObject, entity), PY_READONLY, NULL},
+    {"target", T_OBJECT, offsetof(XMLParserObject, target), PY_READONLY, NULL},
    {NULL}
 };


diff --git a/Modules/_functoolsmodule.c b/Modules/_functoolsmodule.c
@@ -249,11 +249,11 @@ PyDoc_STRVAR(partial_doc,

 #define OFF(x) offsetof(partialobject, x)
 static PyMemberDef partial_memberlist[] = {
-    {"func",            T_OBJECT,       OFF(fn),        READONLY,
+    {"func",            T_OBJECT,       OFF(fn),        PY_READONLY,
     "function object to use in future partial calls"},
-    {"args",            T_OBJECT,       OFF(args),      READONLY,
+    {"args",            T_OBJECT,       OFF(args),      PY_READONLY,
     "tuple of arguments to future partial calls"},
-    {"keywords",        T_OBJECT,       OFF(kw),        READONLY,
+    {"keywords",        T_OBJECT,       OFF(kw),        PY_READONLY,
     "dictionary of keyword arguments to future partial calls"},
    {NULL}  /* Sentinel */
 };
@@ -460,7 +460,7 @@ keyobject_clear(keyobject *ko)

 static PyMemberDef keyobject_members[] = {
    {"obj", T_OBJECT,
-     offsetof(keyobject, object), 0,
+     offsetof(keyobject, object), PY_READWRITE,
     PyDoc_STR("Value wrapped by a key function.")},
    {NULL}
 };

diff --git a/Modules/_hashopenssl.c b/Modules/_hashopenssl.c
@@ -320,7 +320,7 @@ EVP_get_digest_size(EVPobject *self, void *closure)
 }

 static PyMemberDef EVP_members[] = {
-    {"name", T_OBJECT, offsetof(EVPobject, name), READONLY, PyDoc_STR("algorithm name.")},
+    {"name", T_OBJECT, offsetof(EVPobject, name), PY_READONLY, PyDoc_STR("algorithm name.")},
    {NULL}  /* Sentinel */
 };


diff --git a/Modules/_io/bufferedio.c b/Modules/_io/bufferedio.c
@@ -2400,8 +2400,8 @@ static PyMethodDef bufferedreader_methods[] = {
 };

 static PyMemberDef bufferedreader_members[] = {
-    {"raw", T_OBJECT, offsetof(buffered, raw), READONLY},
-    {"_finalizing", T_BOOL, offsetof(buffered, finalizing), 0},
+    {"raw", T_OBJECT, offsetof(buffered, raw), PY_READONLY},
+    {"_finalizing", T_BOOL, offsetof(buffered, finalizing), PY_READWRITE},
    {NULL}
 };

@@ -2486,8 +2486,8 @@ static PyMethodDef bufferedwriter_methods[] = {
 };

 static PyMemberDef bufferedwriter_members[] = {
-    {"raw", T_OBJECT, offsetof(buffered, raw), READONLY},
-    {"_finalizing", T_BOOL, offsetof(buffered, finalizing), 0},
+    {"raw", T_OBJECT, offsetof(buffered, raw), PY_READONLY},
+    {"_finalizing", T_BOOL, offsetof(buffered, finalizing), PY_READWRITE},
    {NULL}
 };

@@ -2657,8 +2657,8 @@ static PyMethodDef bufferedrandom_methods[] = {
 };

 static PyMemberDef bufferedrandom_members[] = {
-    {"raw", T_OBJECT, offsetof(buffered, raw), READONLY},
-    {"_finalizing", T_BOOL, offsetof(buffered, finalizing), 0},
+    {"raw", T_OBJECT, offsetof(buffered, raw), PY_READONLY},
+    {"_finalizing", T_BOOL, offsetof(buffered, finalizing), PY_READWRITE},
    {NULL}
 };


diff --git a/Modules/_io/fileio.c b/Modules/_io/fileio.c
@@ -1170,8 +1170,8 @@ static PyGetSetDef fileio_getsetlist[] = {
 };

 static PyMemberDef fileio_members[] = {
-    {"_blksize", T_UINT, offsetof(fileio, blksize), 0},
-    {"_finalizing", T_BOOL, offsetof(fileio, finalizing), 0},
+    {"_blksize", T_UINT, offsetof(fileio, blksize), PY_READWRITE},
+    {"_finalizing", T_BOOL, offsetof(fileio, finalizing), PY_READWRITE},
    {NULL}
 };


diff --git a/Modules/_io/textio.c b/Modules/_io/textio.c
@@ -3143,11 +3143,11 @@ static PyMethodDef textiowrapper_methods[] = {
 };

 static PyMemberDef textiowrapper_members[] = {
-    {"encoding", T_OBJECT, offsetof(textio, encoding), READONLY},
-    {"buffer", T_OBJECT, offsetof(textio, buffer), READONLY},
-    {"line_buffering", T_BOOL, offsetof(textio, line_buffering), READONLY},
-    {"write_through", T_BOOL, offsetof(textio, write_through), READONLY},
-    {"_finalizing", T_BOOL, offsetof(textio, finalizing), 0},
+    {"encoding", T_OBJECT, offsetof(textio, encoding), PY_READONLY},
+    {"buffer", T_OBJECT, offsetof(textio, buffer), PY_READONLY},
+    {"line_buffering", T_BOOL, offsetof(textio, line_buffering), PY_READONLY},
+    {"write_through", T_BOOL, offsetof(textio, write_through), PY_READONLY},
+    {"_finalizing", T_BOOL, offsetof(textio, finalizing), PY_READWRITE},
    {NULL}
 };


diff --git a/Modules/_io/winconsoleio.c b/Modules/_io/winconsoleio.c
@@ -1107,8 +1107,8 @@ static PyGetSetDef winconsoleio_getsetlist[] = {
 };

 static PyMemberDef winconsoleio_members[] = {
-    {"_blksize", T_UINT, offsetof(winconsoleio, blksize), 0},
-    {"_finalizing", T_BOOL, offsetof(winconsoleio, finalizing), 0},
+    {"_blksize", T_UINT, offsetof(winconsoleio, blksize), PY_READWRITE},
+    {"_finalizing", T_BOOL, offsetof(winconsoleio, finalizing), PY_READWRITE},
    {NULL}
 };