gh-107122: Add clear method to dbm.ndbm module (gh-107126)

1 files changed, 33 insertions, 0 deletions

diff --git a/Modules/_dbmmodule.c b/Modules/_dbmmodule.c
index 5be444d..bd80769 100644
--- a/Modules/_dbmmodule.c
+++ b/Modules/_dbmmodule.c
@@ -414,6 +414,38 @@ _dbm_dbm_setdefault_impl(dbmobject *self, PyTypeObject *cls, const char *key,
     return default_value;
 }
 
+/*[clinic input]
+_dbm.dbm.clear
+    cls: defining_class
+    /
+Remove all items from the database.
+
+[clinic start generated code]*/
+
+static PyObject *
+_dbm_dbm_clear_impl(dbmobject *self, PyTypeObject *cls)
+/*[clinic end generated code: output=8d126b9e1d01a434 input=43aa6ca1acb7f5f5]*/
+{
+    _dbm_state *state = PyType_GetModuleState(cls);
+    assert(state != NULL);
+    check_dbmobject_open(self, state->dbm_error);
+    datum key;
+    // Invalidate cache
+    self->di_size = -1;
+    while (1) {
+        key = dbm_firstkey(self->di_dbm);
+        if (key.dptr == NULL) {
+            break;
+        }
+        if (dbm_delete(self->di_dbm, key) < 0) {
+            dbm_clearerr(self->di_dbm);
+            PyErr_SetString(state->dbm_error, "cannot delete item from database");
+            return NULL;
+        }
+    }
+    Py_RETURN_NONE;
+}
+
 static PyObject *
 dbm__enter__(PyObject *self, PyObject *args)
 {
@@ -431,6 +463,7 @@ static PyMethodDef dbm_methods[] = {
     _DBM_DBM_KEYS_METHODDEF
     _DBM_DBM_GET_METHODDEF
     _DBM_DBM_SETDEFAULT_METHODDEF
+    _DBM_DBM_CLEAR_METHODDEF
     {"__enter__", dbm__enter__, METH_NOARGS, NULL},
     {"__exit__",  dbm__exit__, METH_VARARGS, NULL},
     {NULL,  NULL}           /* sentinel */