gh-83714: Set os.statx() members to None if missing from stx_mask

Author: vstinner

Modules/posixmodule.c

@@ -3319,6 +3319,8 @@ typedef struct {
     struct statx stx;
 } Py_statx_result;
 
+#define Py_statx_result_CAST(op) _Py_CAST(Py_statx_result*, (op))
+
 #define M(attr, type, offset, doc) \
     {attr, type, offset, Py_READONLY, PyDoc_STR(doc)}
 #define MM(attr, type, member, doc) \
@@ -3339,10 +3341,6 @@ static PyMemberDef pystatx_result_members[] = {
     MM(st_blocks, Py_T_ULONGLONG, blocks, "number of blocks allocated"),
     MM(stx_attributes_mask, Py_T_ULONGLONG, attributes_mask,
         "Mask of supported bits in stx_attributes"),
-    MX(st_atime, Py_T_DOUBLE, atime_sec, "time of last access"),
-    MX(st_birthtime, Py_T_DOUBLE, btime_sec, "time of creation"),
-    MX(st_ctime, Py_T_DOUBLE, ctime_sec, "time of last change"),
-    MX(st_mtime, Py_T_DOUBLE, mtime_sec, "time of last modification"),
     MM(stx_rdev_major, Py_T_UINT, rdev_major, "represented device major number"),
     MM(stx_rdev_minor, Py_T_UINT, rdev_minor, "represented device minor number"),
     MX(st_rdev, Py_T_ULONGLONG, rdev, "device type (if inode device)"),
@@ -3384,31 +3382,59 @@ static PyMemberDef pystatx_result_members[] = {
 #undef MM
 #undef M
 
-static PyObject *
-pystatx_result_get_nsec(PyObject *op, void *context)
-{
-    uint16_t offset = (uintptr_t)context;
-    struct statx_timestamp *ts = (void*)op + offset;
-    _posixstate *state = PyType_GetModuleState(Py_TYPE(op));
-    assert(state != NULL);
-    return stat_nanosecond_timestamp(state, ts->tv_sec, ts->tv_nsec);
-}
 
-/* The low 16 bits of the context pointer are the offset from the start of
-   Py_statx_result to the struct statx member. */
-#define GM(attr, type, member, doc) \
-    {#attr, pystatx_result_get_##type, NULL, PyDoc_STR(doc), \
-     (void *)(offsetof(Py_statx_result, stx.stx_##member))}
+#define STATX_GET_DOUBLE(ATTR, MEMBER, MASK) \
+    static PyObject* \
+    pystatx_result_get_##ATTR(PyObject *op, void *Py_UNUSED(context)) \
+    { \
+        Py_statx_result *self = Py_statx_result_CAST(op); \
+        if (!(self->stx.stx_mask & MASK)) { \
+            Py_RETURN_NONE; \
+        } \
+        double btime_sec = self->MEMBER; \
+        return PyFloat_FromDouble(btime_sec); \
+    }
+
+STATX_GET_DOUBLE(st_atime, atime_sec, STATX_ATIME)
+STATX_GET_DOUBLE(st_birthtime, btime_sec, STATX_BTIME)
+STATX_GET_DOUBLE(st_ctime, ctime_sec, STATX_CTIME)
+STATX_GET_DOUBLE(st_mtime, mtime_sec, STATX_MTIME)
+
+#define STATX_GET_NSEC(ATTR, MEMBER, MASK) \
+    static PyObject* \
+    pystatx_result_get_##ATTR(PyObject *op, void *context) \
+    { \
+        Py_statx_result *self = Py_statx_result_CAST(op); \
+        if (!(self->stx.stx_mask & MASK)) { \
+            Py_RETURN_NONE; \
+        } \
+        struct statx_timestamp *ts = &self->stx.MEMBER; \
+        _posixstate *state = PyType_GetModuleState(Py_TYPE(op)); \
+        assert(state != NULL); \
+        return stat_nanosecond_timestamp(state, ts->tv_sec, ts->tv_nsec); \
+    }
+
+STATX_GET_NSEC(st_atime_ns, stx_atime, STATX_ATIME)
+STATX_GET_NSEC(st_birthtime_ns, stx_atime, STATX_BTIME)
+STATX_GET_NSEC(st_ctime_ns, stx_ctime, STATX_CTIME)
+STATX_GET_NSEC(st_mtime_ns, stx_mtime, STATX_MTIME)
+
+#define G(attr, doc) \
+    {#attr, pystatx_result_get_##attr, NULL, PyDoc_STR(doc), NULL}
 
 static PyGetSetDef pystatx_result_getset[] = {
-    GM(st_atime_ns, nsec, atime, "time of last access in nanoseconds"),
-    GM(st_birthtime_ns, nsec, btime, "time of creation in nanoseconds"),
-    GM(st_ctime_ns, nsec, ctime, "time of last change in nanoseconds"),
-    GM(st_mtime_ns, nsec, mtime, "time of last modification in nanoseconds"),
+    G(st_atime, "time of last access"),
+    G(st_birthtime, "time of creation"),
+    G(st_ctime, "time of last modification"),
+    G(st_mtime, "time of last modification"),
+    G(st_atime_ns, "time of last access in nanoseconds"),
+    G(st_birthtime_ns, "time of creation in nanoseconds"),
+    G(st_ctime_ns, "time of last change in nanoseconds"),
+    G(st_mtime_ns, "time of last modification in nanoseconds"),
     {NULL},
 };
 
-#undef GM
+#undef G
 
 static PyObject *
 pystatx_result_repr(PyObject *op)
@@ -3452,23 +3478,25 @@ pystatx_result_repr(PyObject *op)
     }
 
     for (size_t i = 0; i < Py_ARRAY_LENGTH(pystatx_result_getset) - 1; ++i) {
-        if (i > 0) {
-            WRITE_ASCII(", ");
-        }
-
         PyGetSetDef *d = &pystatx_result_getset[i];
-        WRITE_ASCII(d->name);
-        WRITE_ASCII("=");
-
         PyObject *o = d->get(op, d->closure);
         if (o == NULL) {
             goto error;
         }
-        if (PyUnicodeWriter_WriteRepr(writer, o) < 0) {
+
+        if (o != Py_None) {
+            if (i > 0) {
+                WRITE_ASCII(", ");
+            }
+
+            WRITE_ASCII(d->name);
+            WRITE_ASCII("=");
+            if (PyUnicodeWriter_WriteRepr(writer, o) < 0) {
+                Py_DECREF(o);
+                goto error;
+            }
             Py_DECREF(o);
-            goto error;
         }
-        Py_DECREF(o);
     }
 
     WRITE_ASCII(")");