ref: e6b4528626528c2bf11f760bfc660375195e6055
dir: /sys/src/cmd/python/Modules/_sqlite/microprotocols.c/
/* microprotocols.c - minimalist and non-validating protocols implementation
*
* Copyright (C) 2003-2004 Federico Di Gregorio <fog@debian.org>
*
* This file is part of psycopg and was adapted for pysqlite. Federico Di
* Gregorio gave the permission to use it within pysqlite under the following
* license:
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
#include <Python.h>
#include <structmember.h>
#include "cursor.h"
#include "microprotocols.h"
#include "prepare_protocol.h"
/** the adapters registry **/
PyObject *psyco_adapters;
/* microprotocols_init - initialize the adapters dictionary */
int
microprotocols_init(PyObject *dict)
{
/* create adapters dictionary and put it in module namespace */
if ((psyco_adapters = PyDict_New()) == NULL) {
return -1;
}
return PyDict_SetItemString(dict, "adapters", psyco_adapters);
}
/* microprotocols_add - add a reverse type-caster to the dictionary */
int
microprotocols_add(PyTypeObject *type, PyObject *proto, PyObject *cast)
{
PyObject* key;
int rc;
if (proto == NULL) proto = (PyObject*)&SQLitePrepareProtocolType;
key = Py_BuildValue("(OO)", (PyObject*)type, proto);
if (!key) {
return -1;
}
rc = PyDict_SetItem(psyco_adapters, key, cast);
Py_DECREF(key);
return rc;
}
/* microprotocols_adapt - adapt an object to the built-in protocol */
PyObject *
microprotocols_adapt(PyObject *obj, PyObject *proto, PyObject *alt)
{
PyObject *adapter, *key;
/* we don't check for exact type conformance as specified in PEP 246
because the SQLitePrepareProtocolType type is abstract and there is no
way to get a quotable object to be its instance */
/* look for an adapter in the registry */
key = Py_BuildValue("(OO)", (PyObject*)obj->ob_type, proto);
if (!key) {
return NULL;
}
adapter = PyDict_GetItem(psyco_adapters, key);
Py_DECREF(key);
if (adapter) {
PyObject *adapted = PyObject_CallFunctionObjArgs(adapter, obj, NULL);
return adapted;
}
/* try to have the protocol adapt this object*/
if (PyObject_HasAttrString(proto, "__adapt__")) {
PyObject *adapted = PyObject_CallMethod(proto, "__adapt__", "O", obj);
if (adapted) {
if (adapted != Py_None) {
return adapted;
} else {
Py_DECREF(adapted);
}
}
if (PyErr_Occurred() && !PyErr_ExceptionMatches(PyExc_TypeError))
return NULL;
}
/* and finally try to have the object adapt itself */
if (PyObject_HasAttrString(obj, "__conform__")) {
PyObject *adapted = PyObject_CallMethod(obj, "__conform__","O", proto);
if (adapted) {
if (adapted != Py_None) {
return adapted;
} else {
Py_DECREF(adapted);
}
}
if (PyErr_Occurred() && !PyErr_ExceptionMatches(PyExc_TypeError)) {
return NULL;
}
}
/* else set the right exception and return NULL */
PyErr_SetString(ProgrammingError, "can't adapt");
return NULL;
}
/** module-level functions **/
PyObject *
psyco_microprotocols_adapt(Cursor *self, PyObject *args)
{
PyObject *obj, *alt = NULL;
PyObject *proto = (PyObject*)&SQLitePrepareProtocolType;
if (!PyArg_ParseTuple(args, "O|OO", &obj, &proto, &alt)) return NULL;
return microprotocols_adapt(obj, proto, alt);
}