bpo-42064: Migrate to `sqlite3_create_collation_v2` (GH-27156)

This implies that SQLite now takes care of destroying the callback
context (the PyObject callable it has been passed), so we can strip the
collation dict from the connection object.

diff --git a/Modules/_sqlite/connection.c b/Modules/_sqlite/connection.c
index 33d3d4cfbd15e5c7ef251fa6fde0e28d094773c7..af093c3319c8b2b847c2ca0b1975d95a71f7ab85 100644 (file)
--- a/Modules/_sqlite/connection.c
+++ b/Modules/_sqlite/connection.c
@@ -177,11 +177,6 @@ pysqlite_connection_init_impl(pysqlite_Connection *self,
     self->function_pinboard_progress_handler = NULL;
     self->function_pinboard_authorizer_cb = NULL;
 
-    Py_XSETREF(self->collations, PyDict_New());
-    if (!self->collations) {
-        return -1;
-    }
-
     pysqlite_state *state = pysqlite_get_state(NULL);
     self->Warning               = state->Warning;
     self->Error                 = state->Error;
@@ -249,7 +244,6 @@ connection_traverse(pysqlite_Connection *self, visitproc visit, void *arg)
     Py_VISIT(self->function_pinboard_trace_callback);
     Py_VISIT(self->function_pinboard_progress_handler);
     Py_VISIT(self->function_pinboard_authorizer_cb);
-    Py_VISIT(self->collations);
     return 0;
 }
 
@@ -265,7 +259,6 @@ connection_clear(pysqlite_Connection *self)
     Py_CLEAR(self->function_pinboard_trace_callback);
     Py_CLEAR(self->function_pinboard_progress_handler);
     Py_CLEAR(self->function_pinboard_authorizer_cb);
-    Py_CLEAR(self->collations);
     return 0;
 }
 
@@ -1780,29 +1773,29 @@ pysqlite_connection_create_collation_impl(pysqlite_Connection *self,
     if (!uppercase_name_str)
         goto finally;
 
-    if (callable != Py_None && !PyCallable_Check(callable)) {
-        PyErr_SetString(PyExc_TypeError, "parameter must be callable");
-        goto finally;
+    int flags = SQLITE_UTF8;
+    if (callable == Py_None) {
+        rc = sqlite3_create_collation_v2(self->db, uppercase_name_str, flags,
+                                         NULL, NULL, NULL);
     }
-
-    if (callable != Py_None) {
-        if (PyDict_SetItem(self->collations, uppercase_name, callable) == -1)
-            goto finally;
-    } else {
-        if (PyDict_DelItem(self->collations, uppercase_name) == -1)
+    else {
+        if (!PyCallable_Check(callable)) {
+            PyErr_SetString(PyExc_TypeError, "parameter must be callable");
             goto finally;
+        }
+        rc = sqlite3_create_collation_v2(self->db, uppercase_name_str, flags,
+                                         Py_NewRef(callable),
+                                         &pysqlite_collation_callback,
+                                         &_destructor);
     }
 
-    rc = sqlite3_create_collation(self->db,
-                                  uppercase_name_str,
-                                  SQLITE_UTF8,
-                                  (callable != Py_None) ? callable : NULL,
-                                  (callable != Py_None) ? pysqlite_collation_callback : NULL);
     if (rc != SQLITE_OK) {
+        /* Unlike other sqlite3_* functions, the destructor callback is _not_
+         * called if sqlite3_create_collation_v2() fails, so we have to free
+         * the context before returning.
+         */
         if (callable != Py_None) {
-            if (PyDict_DelItem(self->collations, uppercase_name) < 0) {
-                PyErr_Clear();
-            }
+            Py_DECREF(callable);
         }
         _pysqlite_seterror(self->db);
         goto finally;

diff --git a/Modules/_sqlite/connection.h b/Modules/_sqlite/connection.h
index 5e7e7e5abe066879a2819765bf7aba25731579ba..50c2015be3eb1938f158df812c71684a510f0fea 100644 (file)
--- a/Modules/_sqlite/connection.h
+++ b/Modules/_sqlite/connection.h
@@ -82,9 +82,6 @@ typedef struct
     PyObject* function_pinboard_progress_handler;
     PyObject* function_pinboard_authorizer_cb;
 
-    /* a dictionary of registered collation name => collation callable mappings */
-    PyObject* collations;
-
     /* Exception objects: borrowed refs. */
     PyObject* Warning;
     PyObject* Error;