Issue #18520: Add a new PyStructSequence_InitType2() function, same than

PyStructSequence_InitType() except that it has a return value (0 on success,
-1 on error).

 * PyStructSequence_InitType2() now raises MemoryError on memory allocation failure
 * Fix also some calls to PyDict_SetItemString(): handle error

3 files changed, 37 insertions, 15 deletions

diff --git a/Objects/floatobject.c b/Objects/floatobject.c
index 1398fa5..7ee2034 100644
--- a/Objects/floatobject.c
+++ b/Objects/floatobject.c
@@ -1853,7 +1853,7 @@ PyTypeObject PyFloat_Type = {
     float_new,                                  /* tp_new */
 };
 
-void
+int
 _PyFloat_Init(void)
 {
     /* We attempt to determine if this machine is using IEEE
@@ -1903,8 +1903,11 @@ _PyFloat_Init(void)
     float_format = detected_float_format;
 
     /* Init float info */
-    if (FloatInfoType.tp_name == 0)
-        PyStructSequence_InitType(&FloatInfoType, &floatinfo_desc);
+    if (FloatInfoType.tp_name == NULL) {
+        if (PyStructSequence_InitType2(&FloatInfoType, &floatinfo_desc) < 0)
+            return 0;
+    }
+    return 1;
 }
 
 int
diff --git a/Objects/longobject.c b/Objects/longobject.c
index 925e55a..ce75888 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -5059,8 +5059,10 @@ _PyLong_Init(void)
     }
 #endif
     /* initialize int_info */
-    if (Int_InfoType.tp_name == 0)
-        PyStructSequence_InitType(&Int_InfoType, &int_info_desc);
+    if (Int_InfoType.tp_name == NULL) {
+        if (PyStructSequence_InitType2(&Int_InfoType, &int_info_desc) < 0)
+            return 0;
+    }
 
     return 1;
 }
diff --git a/Objects/structseq.c b/Objects/structseq.c
index 5553267..664344b 100644
--- a/Objects/structseq.c
+++ b/Objects/structseq.c
@@ -320,12 +320,13 @@ static PyTypeObject _struct_sequence_template = {
     structseq_new,                              /* tp_new */
 };
 
-void
-PyStructSequence_InitType(PyTypeObject *type, PyStructSequence_Desc *desc)
+int
+PyStructSequence_InitType2(PyTypeObject *type, PyStructSequence_Desc *desc)
 {
     PyObject *dict;
     PyMemberDef* members;
     int n_members, n_unnamed_members, i, k;
+    PyObject *v;
 
 #ifdef Py_TRACE_REFS
     /* if the type object was chained, unchain it first
@@ -347,8 +348,10 @@ PyStructSequence_InitType(PyTypeObject *type, PyStructSequence_Desc *desc)
     type->tp_doc = desc->doc;
 
     members = PyMem_NEW(PyMemberDef, n_members-n_unnamed_members+1);
-    if (members == NULL)
-        return;
+    if (members == NULL) {
+        PyErr_NoMemory();
+        return -1;
+    }
 
     for (i = k = 0; i < n_members; ++i) {
         if (desc->fields[i].name == PyStructSequence_UnnamedField)
@@ -366,22 +369,33 @@ PyStructSequence_InitType(PyTypeObject *type, PyStructSequence_Desc *desc)
     type->tp_members = members;
 
     if (PyType_Ready(type) < 0)
-        return;
+        return -1;
     Py_INCREF(type);
 
     dict = type->tp_dict;
 #define SET_DICT_FROM_INT(key, value)                           \
     do {                                                        \
-        PyObject *v = PyLong_FromLong((long) value);            \
-        if (v != NULL) {                                        \
-            PyDict_SetItemString(dict, key, v);                 \
+        v = PyLong_FromLong((long) value);                      \
+        if (v == NULL)                                          \
+            return -1;                                          \
+        if (PyDict_SetItemString(dict, key, v) < 0) {           \
             Py_DECREF(v);                                       \
+            return -1;                                          \
         }                                                       \
+        Py_DECREF(v);                                           \
     } while (0)
 
     SET_DICT_FROM_INT(visible_length_key, desc->n_in_sequence);
     SET_DICT_FROM_INT(real_length_key, n_members);
     SET_DICT_FROM_INT(unnamed_fields_key, n_unnamed_members);
+
+    return 0;
+}
+
+void
+PyStructSequence_InitType(PyTypeObject *type, PyStructSequence_Desc *desc)
+{
+    (void)PyStructSequence_InitType2(type, desc);
 }
 
 PyTypeObject*
@@ -390,8 +404,11 @@ PyStructSequence_NewType(PyStructSequence_Desc *desc)
     PyTypeObject *result;
 
     result = (PyTypeObject*)PyType_GenericAlloc(&PyType_Type, 0);
-    if (result != NULL) {
-        PyStructSequence_InitType(result, desc);
+    if (result == NULL)
+        return NULL;
+    if (PyStructSequence_InitType2(result, desc) < 0) {
+        Py_DECREF(result);
+        return NULL;
     }
     return result;
 }