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Diffstat (limited to 'src/microprotocols.c')
-rw-r--r-- | src/microprotocols.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/src/microprotocols.c b/src/microprotocols.c new file mode 100644 index 0000000..c730afa --- /dev/null +++ b/src/microprotocols.c @@ -0,0 +1,142 @@ +/* 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; + +/* pysqlite_microprotocols_init - initialize the adapters dictionary */ + +int +pysqlite_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); +} + + +/* pysqlite_microprotocols_add - add a reverse type-caster to the dictionary */ + +int +pysqlite_microprotocols_add(PyTypeObject *type, PyObject *proto, PyObject *cast) +{ + PyObject* key; + int rc; + + if (proto == NULL) proto = (PyObject*)&pysqlite_PrepareProtocolType; + + key = Py_BuildValue("(OO)", (PyObject*)type, proto); + if (!key) { + return -1; + } + + rc = PyDict_SetItem(psyco_adapters, key, cast); + Py_DECREF(key); + + return rc; +} + +/* pysqlite_microprotocols_adapt - adapt an object to the built-in protocol */ + +PyObject * +pysqlite_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 pysqlite_PrepareProtocolType 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(pysqlite_ProgrammingError, "can't adapt"); + return NULL; +} + +/** module-level functions **/ + +PyObject * +pysqlite_adapt(pysqlite_Cursor *self, PyObject *args) +{ + PyObject *obj, *alt = NULL; + PyObject *proto = (PyObject*)&pysqlite_PrepareProtocolType; + + if (!PyArg_ParseTuple(args, "O|OO", &obj, &proto, &alt)) return NULL; + return pysqlite_microprotocols_adapt(obj, proto, alt); +} |