tdb2: python wrapper
authorRusty Russell <rusty@rustcorp.com.au>
Mon, 20 Jun 2011 09:10:33 +0000 (18:40 +0930)
committerRusty Russell <rusty@rustcorp.com.au>
Mon, 20 Jun 2011 09:18:35 +0000 (11:18 +0200)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
lib/tdb2/pytdb.c [new file with mode: 0644]

diff --git a/lib/tdb2/pytdb.c b/lib/tdb2/pytdb.c
new file mode 100644 (file)
index 0000000..86f6048
--- /dev/null
@@ -0,0 +1,574 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   Python interface to tdb2.  Simply modified from tdb1 version.
+
+   Copyright (C) 2004-2006 Tim Potter <tpot@samba.org>
+   Copyright (C) 2007-2008 Jelmer Vernooij <jelmer@samba.org>
+   Copyright (C) 2011 Rusty Russell <rusty@rustcorp.com.au>
+
+     ** NOTE! The following LGPL license applies to the tdb
+     ** library. This does NOT imply that all of Samba is released
+     ** under the LGPL
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <Python.h>
+#include "replace.h"
+#include "system/filesys.h"
+
+#ifndef Py_RETURN_NONE
+#define Py_RETURN_NONE return Py_INCREF(Py_None), Py_None
+#endif
+
+/* Include tdb headers */
+#include <tdb2.h>
+
+typedef struct {
+       PyObject_HEAD
+       struct tdb_context *ctx;
+       bool closed;
+} PyTdbObject;
+
+staticforward PyTypeObject PyTdb;
+
+static void PyErr_SetTDBError(enum TDB_ERROR e)
+{
+       PyErr_SetObject(PyExc_RuntimeError,
+               Py_BuildValue("(i,s)", e, tdb_errorstr(e)));
+}
+
+static TDB_DATA PyString_AsTDB_DATA(PyObject *data)
+{
+       TDB_DATA ret;
+       ret.dptr = (unsigned char *)PyString_AsString(data);
+       ret.dsize = PyString_Size(data);
+       return ret;
+}
+
+static PyObject *PyString_FromTDB_DATA(TDB_DATA data)
+{
+       PyObject *ret = PyString_FromStringAndSize((const char *)data.dptr,
+                                                  data.dsize);
+       free(data.dptr);
+       return ret;
+}
+
+#define PyErr_TDB_ERROR_IS_ERR_RAISE(ret) \
+       if (ret != TDB_SUCCESS) { \
+               PyErr_SetTDBError(ret); \
+               return NULL; \
+       }
+
+static PyObject *py_tdb_open(PyTypeObject *type, PyObject *args, PyObject *kwargs)
+{
+       char *name = NULL;
+       int tdb_flags = TDB_DEFAULT, flags = O_RDWR, mode = 0600;
+       struct tdb_context *ctx;
+       PyTdbObject *ret;
+       const char *kwnames[] = { "name", "tdb_flags", "flags", "mode", NULL };
+
+       if (!PyArg_ParseTupleAndKeywords(args, kwargs, "|siii", (char **)kwnames, &name, &tdb_flags, &flags, &mode))
+               return NULL;
+
+       if (name == NULL) {
+               tdb_flags |= TDB_INTERNAL;
+       }
+
+       ctx = tdb_open(name, tdb_flags, flags, mode, NULL);
+       if (ctx == NULL) {
+               PyErr_SetFromErrno(PyExc_IOError);
+               return NULL;
+       }
+
+       ret = PyObject_New(PyTdbObject, &PyTdb);
+       if (!ret) {
+               tdb_close(ctx);
+               return NULL;
+       }
+
+       ret->ctx = ctx;
+       ret->closed = false;
+       return (PyObject *)ret;
+}
+
+static PyObject *obj_transaction_cancel(PyTdbObject *self)
+{
+       tdb_transaction_cancel(self->ctx);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_transaction_commit(PyTdbObject *self)
+{
+       enum TDB_ERROR ret = tdb_transaction_commit(self->ctx);
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_transaction_prepare_commit(PyTdbObject *self)
+{
+       enum TDB_ERROR ret = tdb_transaction_prepare_commit(self->ctx);
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_transaction_start(PyTdbObject *self)
+{
+       enum TDB_ERROR ret = tdb_transaction_start(self->ctx);
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_lockall(PyTdbObject *self)
+{
+       enum TDB_ERROR ret = tdb_lockall(self->ctx);
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_unlockall(PyTdbObject *self)
+{
+       tdb_unlockall(self->ctx);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_lockall_read(PyTdbObject *self)
+{
+       enum TDB_ERROR ret = tdb_lockall_read(self->ctx);
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_unlockall_read(PyTdbObject *self)
+{
+       tdb_unlockall_read(self->ctx);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_close(PyTdbObject *self)
+{
+       enum TDB_ERROR ret;
+       if (self->closed)
+               Py_RETURN_NONE;
+       ret = tdb_close(self->ctx);
+       self->closed = true;
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_get(PyTdbObject *self, PyObject *args)
+{
+       TDB_DATA key, data;
+       PyObject *py_key;
+       enum TDB_ERROR ret;
+       if (!PyArg_ParseTuple(args, "O", &py_key))
+               return NULL;
+
+       key = PyString_AsTDB_DATA(py_key);
+       ret = tdb_fetch(self->ctx, key, &data);
+       if (ret == TDB_ERR_NOEXIST)
+               Py_RETURN_NONE;
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       return PyString_FromTDB_DATA(data);
+}
+
+static PyObject *obj_append(PyTdbObject *self, PyObject *args)
+{
+       TDB_DATA key, data;
+       PyObject *py_key, *py_data;
+       enum TDB_ERROR ret;
+       if (!PyArg_ParseTuple(args, "OO", &py_key, &py_data))
+               return NULL;
+
+       key = PyString_AsTDB_DATA(py_key);
+       data = PyString_AsTDB_DATA(py_data);
+
+       ret = tdb_append(self->ctx, key, data);
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_firstkey(PyTdbObject *self)
+{
+       enum TDB_ERROR ret;
+       TDB_DATA key;
+
+       ret = tdb_firstkey(self->ctx, &key);
+       if (ret == TDB_ERR_NOEXIST)
+               Py_RETURN_NONE;
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+
+       return PyString_FromTDB_DATA(key);
+}
+
+static PyObject *obj_nextkey(PyTdbObject *self, PyObject *args)
+{
+       TDB_DATA key;
+       PyObject *py_key;
+       enum TDB_ERROR ret;
+       if (!PyArg_ParseTuple(args, "O", &py_key))
+               return NULL;
+
+       /* Malloc here, since tdb_nextkey frees. */
+       key.dsize = PyString_Size(py_key);
+       key.dptr = malloc(key.dsize);
+       memcpy(key.dptr, PyString_AsString(py_key), key.dsize);
+
+       ret = tdb_nextkey(self->ctx, &key);
+       if (ret == TDB_ERR_NOEXIST)
+               Py_RETURN_NONE;
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+
+       return PyString_FromTDB_DATA(key);
+}
+
+static PyObject *obj_delete(PyTdbObject *self, PyObject *args)
+{
+       TDB_DATA key;
+       PyObject *py_key;
+       enum TDB_ERROR ret;
+       if (!PyArg_ParseTuple(args, "O", &py_key))
+               return NULL;
+
+       key = PyString_AsTDB_DATA(py_key);
+       ret = tdb_delete(self->ctx, key);
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_has_key(PyTdbObject *self, PyObject *args)
+{
+       TDB_DATA key;
+       enum TDB_ERROR ret;
+       PyObject *py_key;
+       if (!PyArg_ParseTuple(args, "O", &py_key))
+               return NULL;
+
+       key = PyString_AsTDB_DATA(py_key);
+       ret = tdb_exists(self->ctx, key);
+       if (ret == TDB_ERR_NOEXIST)
+               return Py_False;
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       return Py_True;
+}
+
+static PyObject *obj_store(PyTdbObject *self, PyObject *args)
+{
+       TDB_DATA key, value;
+       enum TDB_ERROR ret;
+       int flag = TDB_REPLACE;
+       PyObject *py_key, *py_value;
+
+       if (!PyArg_ParseTuple(args, "OO|i", &py_key, &py_value, &flag))
+               return NULL;
+
+       key = PyString_AsTDB_DATA(py_key);
+       value = PyString_AsTDB_DATA(py_value);
+
+       ret = tdb_store(self->ctx, key, value, flag);
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_add_flag(PyTdbObject *self, PyObject *args)
+{
+       unsigned flag;
+
+       if (!PyArg_ParseTuple(args, "I", &flag))
+               return NULL;
+
+       tdb_add_flag(self->ctx, flag);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_remove_flag(PyTdbObject *self, PyObject *args)
+{
+       unsigned flag;
+
+       if (!PyArg_ParseTuple(args, "I", &flag))
+               return NULL;
+
+       tdb_remove_flag(self->ctx, flag);
+       Py_RETURN_NONE;
+}
+
+typedef struct {
+       PyObject_HEAD
+       TDB_DATA current;
+       bool end;
+       PyTdbObject *iteratee;
+} PyTdbIteratorObject;
+
+static PyObject *tdb_iter_next(PyTdbIteratorObject *self)
+{
+       enum TDB_ERROR e;
+       PyObject *ret;
+       if (self->end)
+               return NULL;
+       ret = PyString_FromStringAndSize((const char *)self->current.dptr,
+                                        self->current.dsize);
+       e = tdb_nextkey(self->iteratee->ctx, &self->current);
+       if (e == TDB_ERR_NOEXIST)
+               self->end = true;
+       else
+               PyErr_TDB_ERROR_IS_ERR_RAISE(e);
+       return ret;
+}
+
+static void tdb_iter_dealloc(PyTdbIteratorObject *self)
+{
+       Py_DECREF(self->iteratee);
+       PyObject_Del(self);
+}
+
+PyTypeObject PyTdbIterator = {
+       .tp_name = "Iterator",
+       .tp_basicsize = sizeof(PyTdbIteratorObject),
+       .tp_iternext = (iternextfunc)tdb_iter_next,
+       .tp_dealloc = (destructor)tdb_iter_dealloc,
+       .tp_flags = Py_TPFLAGS_DEFAULT,
+       .tp_iter = PyObject_SelfIter,
+};
+
+static PyObject *tdb_object_iter(PyTdbObject *self)
+{
+       PyTdbIteratorObject *ret;
+       enum TDB_ERROR e;
+
+       ret = PyObject_New(PyTdbIteratorObject, &PyTdbIterator);
+       if (!ret)
+               return NULL;
+       e = tdb_firstkey(self->ctx, &ret->current);
+       if (e == TDB_ERR_NOEXIST) {
+               ret->end = true;
+       } else {
+               PyErr_TDB_ERROR_IS_ERR_RAISE(e);
+               ret->end = false;
+       }
+       ret->iteratee = self;
+       Py_INCREF(self);
+       return (PyObject *)ret;
+}
+
+static PyObject *obj_clear(PyTdbObject *self)
+{
+       enum TDB_ERROR ret = tdb_wipe_all(self->ctx);
+       PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+       Py_RETURN_NONE;
+}
+
+static PyObject *obj_enable_seqnum(PyTdbObject *self)
+{
+       tdb_add_flag(self->ctx, TDB_SEQNUM);
+       Py_RETURN_NONE;
+}
+
+static PyMethodDef tdb_object_methods[] = {
+       { "transaction_cancel", (PyCFunction)obj_transaction_cancel, METH_NOARGS,
+               "S.transaction_cancel() -> None\n"
+               "Cancel the currently active transaction." },
+       { "transaction_commit", (PyCFunction)obj_transaction_commit, METH_NOARGS,
+               "S.transaction_commit() -> None\n"
+               "Commit the currently active transaction." },
+       { "transaction_prepare_commit", (PyCFunction)obj_transaction_prepare_commit, METH_NOARGS,
+               "S.transaction_prepare_commit() -> None\n"
+               "Prepare to commit the currently active transaction" },
+       { "transaction_start", (PyCFunction)obj_transaction_start, METH_NOARGS,
+               "S.transaction_start() -> None\n"
+               "Start a new transaction." },
+       { "lock_all", (PyCFunction)obj_lockall, METH_NOARGS, NULL },
+       { "unlock_all", (PyCFunction)obj_unlockall, METH_NOARGS, NULL },
+       { "read_lock_all", (PyCFunction)obj_lockall_read, METH_NOARGS, NULL },
+       { "read_unlock_all", (PyCFunction)obj_unlockall_read, METH_NOARGS, NULL },
+       { "close", (PyCFunction)obj_close, METH_NOARGS, NULL },
+       { "get", (PyCFunction)obj_get, METH_VARARGS, "S.get(key) -> value\n"
+               "Fetch a value." },
+       { "append", (PyCFunction)obj_append, METH_VARARGS, "S.append(key, value) -> None\n"
+               "Append data to an existing key." },
+       { "firstkey", (PyCFunction)obj_firstkey, METH_NOARGS, "S.firstkey() -> data\n"
+               "Return the first key in this database." },
+       { "nextkey", (PyCFunction)obj_nextkey, METH_NOARGS, "S.nextkey(key) -> data\n"
+               "Return the next key in this database." },
+       { "delete", (PyCFunction)obj_delete, METH_VARARGS, "S.delete(key) -> None\n"
+               "Delete an entry." },
+       { "has_key", (PyCFunction)obj_has_key, METH_VARARGS, "S.has_key(key) -> None\n"
+               "Check whether key exists in this database." },
+       { "store", (PyCFunction)obj_store, METH_VARARGS, "S.store(key, data, flag=REPLACE) -> None"
+               "Store data." },
+       { "add_flag", (PyCFunction)obj_add_flag, METH_VARARGS, "S.add_flag(flag) -> None" },
+       { "remove_flag", (PyCFunction)obj_remove_flag, METH_VARARGS, "S.remove_flag(flag) -> None" },
+       { "iterkeys", (PyCFunction)tdb_object_iter, METH_NOARGS, "S.iterkeys() -> iterator" },
+       { "clear", (PyCFunction)obj_clear, METH_NOARGS, "S.clear() -> None\n"
+               "Wipe the entire database." },
+       { "enable_seqnum", (PyCFunction)obj_enable_seqnum, METH_NOARGS,
+               "S.enable_seqnum() -> None" },
+       { NULL }
+};
+
+static PyObject *obj_get_flags(PyTdbObject *self, void *closure)
+{
+       return PyInt_FromLong(tdb_get_flags(self->ctx));
+}
+
+static PyObject *obj_get_filename(PyTdbObject *self, void *closure)
+{
+       return PyString_FromString(tdb_name(self->ctx));
+}
+
+static PyObject *obj_get_seqnum(PyTdbObject *self, void *closure)
+{
+       return PyInt_FromLong(tdb_get_seqnum(self->ctx));
+}
+
+
+static PyGetSetDef tdb_object_getsetters[] = {
+       { (char *)"flags", (getter)obj_get_flags, NULL, NULL },
+       { (char *)"filename", (getter)obj_get_filename, NULL, (char *)"The filename of this TDB file."},
+       { (char *)"seqnum", (getter)obj_get_seqnum, NULL, NULL },
+       { NULL }
+};
+
+static PyObject *tdb_object_repr(PyTdbObject *self)
+{
+       if (tdb_get_flags(self->ctx) & TDB_INTERNAL) {
+               return PyString_FromString("Tdb(<internal>)");
+       } else {
+               return PyString_FromFormat("Tdb('%s')", tdb_name(self->ctx));
+       }
+}
+
+static void tdb_object_dealloc(PyTdbObject *self)
+{
+       if (!self->closed)
+               tdb_close(self->ctx);
+       self->ob_type->tp_free(self);
+}
+
+static PyObject *obj_getitem(PyTdbObject *self, PyObject *key)
+{
+       TDB_DATA tkey, val;
+       enum TDB_ERROR ret;
+
+       if (!PyString_Check(key)) {
+               PyErr_SetString(PyExc_TypeError, "Expected string as key");
+               return NULL;
+       }
+
+       tkey.dptr = (unsigned char *)PyString_AsString(key);
+       tkey.dsize = PyString_Size(key);
+
+       ret = tdb_fetch(self->ctx, tkey, &val);
+       if (ret == TDB_ERR_NOEXIST) {
+               PyErr_SetString(PyExc_KeyError, "No such TDB entry");
+               return NULL;
+       } else {
+               PyErr_TDB_ERROR_IS_ERR_RAISE(ret);
+               return PyString_FromTDB_DATA(val);
+       }
+}
+
+static int obj_setitem(PyTdbObject *self, PyObject *key, PyObject *value)
+{
+       TDB_DATA tkey, tval;
+       enum TDB_ERROR ret;
+       if (!PyString_Check(key)) {
+               PyErr_SetString(PyExc_TypeError, "Expected string as key");
+               return -1;
+       }
+
+       tkey = PyString_AsTDB_DATA(key);
+
+       if (value == NULL) {
+               ret = tdb_delete(self->ctx, tkey);
+       } else {
+               if (!PyString_Check(value)) {
+                       PyErr_SetString(PyExc_TypeError, "Expected string as value");
+                       return -1;
+               }
+
+               tval = PyString_AsTDB_DATA(value);
+
+               ret = tdb_store(self->ctx, tkey, tval, TDB_REPLACE);
+       }
+
+       if (ret != TDB_SUCCESS) {
+               PyErr_SetTDBError(ret);
+               return -1;
+       }
+
+       return ret;
+}
+
+static PyMappingMethods tdb_object_mapping = {
+       .mp_subscript = (binaryfunc)obj_getitem,
+       .mp_ass_subscript = (objobjargproc)obj_setitem,
+};
+static PyTypeObject PyTdb = {
+       .tp_name = "Tdb",
+       .tp_basicsize = sizeof(PyTdbObject),
+       .tp_methods = tdb_object_methods,
+       .tp_getset = tdb_object_getsetters,
+       .tp_new = py_tdb_open,
+       .tp_doc = "A TDB file",
+       .tp_repr = (reprfunc)tdb_object_repr,
+       .tp_dealloc = (destructor)tdb_object_dealloc,
+       .tp_as_mapping = &tdb_object_mapping,
+       .tp_flags = Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE|Py_TPFLAGS_HAVE_ITER,
+       .tp_iter = (getiterfunc)tdb_object_iter,
+};
+
+static PyMethodDef tdb_methods[] = {
+       { "open", (PyCFunction)py_tdb_open, METH_VARARGS|METH_KEYWORDS, "open(name, hash_size=0, tdb_flags=TDB_DEFAULT, flags=O_RDWR, mode=0600)\n"
+               "Open a TDB file." },
+       { NULL }
+};
+
+void inittdb(void);
+void inittdb(void)
+{
+       PyObject *m;
+
+       if (PyType_Ready(&PyTdb) < 0)
+               return;
+
+       if (PyType_Ready(&PyTdbIterator) < 0)
+               return;
+
+       m = Py_InitModule3("tdb", tdb_methods, "TDB is a simple key-value database similar to GDBM that supports multiple writers.");
+       if (m == NULL)
+               return;
+
+       PyModule_AddObject(m, "REPLACE", PyInt_FromLong(TDB_REPLACE));
+       PyModule_AddObject(m, "INSERT", PyInt_FromLong(TDB_INSERT));
+       PyModule_AddObject(m, "MODIFY", PyInt_FromLong(TDB_MODIFY));
+
+       PyModule_AddObject(m, "DEFAULT", PyInt_FromLong(TDB_DEFAULT));
+       PyModule_AddObject(m, "INTERNAL", PyInt_FromLong(TDB_INTERNAL));
+       PyModule_AddObject(m, "NOLOCK", PyInt_FromLong(TDB_NOLOCK));
+       PyModule_AddObject(m, "NOMMAP", PyInt_FromLong(TDB_NOMMAP));
+       PyModule_AddObject(m, "CONVERT", PyInt_FromLong(TDB_CONVERT));
+       PyModule_AddObject(m, "NOSYNC", PyInt_FromLong(TDB_NOSYNC));
+       PyModule_AddObject(m, "SEQNUM", PyInt_FromLong(TDB_SEQNUM));
+       PyModule_AddObject(m, "ALLOW_NESTING", PyInt_FromLong(TDB_ALLOW_NESTING));
+
+       PyModule_AddObject(m, "__docformat__", PyString_FromString("restructuredText"));
+
+       PyModule_AddObject(m, "__version__", PyString_FromString(PACKAGE_VERSION));
+
+       Py_INCREF(&PyTdb);
+       PyModule_AddObject(m, "Tdb", (PyObject *)&PyTdb);
+
+       Py_INCREF(&PyTdbIterator);
+}