[3.10] bpo-42972: Track sqlite3 statement objects (GH-26475) (GH-26515)

Allocate and track statement objects in pysqlite_statement_create.

By allocating and tracking creation of statement object in
pysqlite_statement_create(), the caller does not need to worry about GC
syncronization, and eliminates the possibility of getting a badly
created object. All related fault handling is moved to
pysqlite_statement_create().

Co-authored-by: Victor Stinner <vstinner@python.org>.
(cherry picked from commit fffa0f92adaaed0bcb3907d982506f78925e9052)

Co-authored-by: Erlend Egeberg Aasland <erlend.aasland@innova.no>

1 files changed, 2 insertions, 7 deletions

diff --git a/Modules/_sqlite/cursor.c b/Modules/_sqlite/cursor.c
index 558b43a..0335e98 100644
--- a/Modules/_sqlite/cursor.c
+++ b/Modules/_sqlite/cursor.c
@@ -507,13 +507,8 @@ _pysqlite_query_execute(pysqlite_Cursor* self, int multiple, PyObject* operation
 
     if (self->statement->in_use) {
         Py_SETREF(self->statement,
-                  PyObject_GC_New(pysqlite_Statement, pysqlite_StatementType));
-        if (!self->statement) {
-            goto error;
-        }
-        rc = pysqlite_statement_create(self->statement, self->connection, operation);
-        if (rc != SQLITE_OK) {
-            Py_CLEAR(self->statement);
+                  pysqlite_statement_create(self->connection, operation));
+        if (self->statement == NULL) {
             goto error;
         }
     }