lib/tdb/pytdb.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Python interface to tdb.
   5
   6    Copyright (C) 2004-2006 Tim Potter <tpot@samba.org>
   7    Copyright (C) 2007-2008 Jelmer Vernooij <jelmer@samba.org>
   8
   9      ** NOTE! The following LGPL license applies to the tdb
  10      ** library. This does NOT imply that all of Samba is released
  11      ** under the LGPL
  12
  13    This library is free software; you can redistribute it and/or
  14    modify it under the terms of the GNU Lesser General Public
  15    License as published by the Free Software Foundation; either
  16    version 3 of the License, or (at your option) any later version.
  17
  18    This library is distributed in the hope that it will be useful,
  19    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21    Lesser General Public License for more details.
  22
  23    You should have received a copy of the GNU Lesser General Public
  24    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  25 */
  26
  27 #include "replace.h"
  28 #include "system/filesys.h"
  29
  30 #include <Python.h>
  31 #ifndef Py_RETURN_NONE
  32 #define Py_RETURN_NONE return Py_INCREF(Py_None), Py_None
  33 #endif
  34
  35 /* Include tdb headers */
  36 #include <tdb.h>
  37
  38 typedef struct {
  39         PyObject_HEAD
  40         TDB_CONTEXT *ctx;
  41         bool closed;
  42 } PyTdbObject;
  43
  44 PyAPI_DATA(PyTypeObject) PyTdb;
  45
  46 static void PyErr_SetTDBError(TDB_CONTEXT *tdb)
  47 {
  48         PyErr_SetObject(PyExc_RuntimeError,
  49                 Py_BuildValue("(i,s)", tdb_error(tdb), tdb_errorstr(tdb)));
  50 }
  51
  52 static TDB_DATA PyString_AsTDB_DATA(PyObject *data)
  53 {
  54         TDB_DATA ret;
  55         ret.dptr = (unsigned char *)PyString_AsString(data);
  56         ret.dsize = PyString_Size(data);
  57         return ret;
  58 }
  59
  60 static PyObject *PyString_FromTDB_DATA(TDB_DATA data)
  61 {
  62         if (data.dptr == NULL && data.dsize == 0) {
  63                 Py_RETURN_NONE;
  64         } else {
  65                 PyObject *ret = PyString_FromStringAndSize((const char *)data.dptr,
  66                                                                                                    data.dsize);
  67                 free(data.dptr);
  68                 return ret;
  69     }
  70 }
  71
  72 #define PyErr_TDB_ERROR_IS_ERR_RAISE(ret, tdb) \
  73         if (ret != 0) { \
  74                 PyErr_SetTDBError(tdb); \
  75                 return NULL; \
  76         }
  77
  78 static PyObject *py_tdb_open(PyTypeObject *type, PyObject *args, PyObject *kwargs)
  79 {
  80         char *name;
  81         int hash_size = 0, tdb_flags = TDB_DEFAULT, flags = O_RDWR, mode = 0600;
  82         TDB_CONTEXT *ctx;
  83         PyTdbObject *ret;
  84         const char *kwnames[] = { "name", "hash_size", "tdb_flags", "flags", "mode", NULL };
  85
  86         if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s|iiii", (char **)kwnames, &name, &hash_size, &tdb_flags, &flags, &mode))
  87                 return NULL;
  88
  89         ctx = tdb_open(name, hash_size, tdb_flags, flags, mode);
  90         if (ctx == NULL) {
  91                 PyErr_SetFromErrno(PyExc_IOError);
  92                 return NULL;
  93         }
  94
  95         ret = PyObject_New(PyTdbObject, &PyTdb);
  96         ret->ctx = ctx;
  97         ret->closed = false;
  98         return (PyObject *)ret;
  99 }
 100
 101 static PyObject *obj_transaction_cancel(PyTdbObject *self)
 102 {
 103         int ret = tdb_transaction_cancel(self->ctx);
 104         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 105         Py_RETURN_NONE;
 106 }
 107
 108 static PyObject *obj_transaction_commit(PyTdbObject *self)
 109 {
 110         int ret = tdb_transaction_commit(self->ctx);
 111         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 112         Py_RETURN_NONE;
 113 }
 114
 115 static PyObject *obj_transaction_start(PyTdbObject *self)
 116 {
 117         int ret = tdb_transaction_start(self->ctx);
 118         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 119         Py_RETURN_NONE;
 120 }
 121
 122 static PyObject *obj_reopen(PyTdbObject *self)
 123 {
 124         int ret = tdb_reopen(self->ctx);
 125         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 126         Py_RETURN_NONE;
 127 }
 128
 129 static PyObject *obj_lockall(PyTdbObject *self)
 130 {
 131         int ret = tdb_lockall(self->ctx);
 132         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 133         Py_RETURN_NONE;
 134 }
 135
 136 static PyObject *obj_unlockall(PyTdbObject *self)
 137 {
 138         int ret = tdb_unlockall(self->ctx);
 139         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 140         Py_RETURN_NONE;
 141 }
 142
 143 static PyObject *obj_lockall_read(PyTdbObject *self)
 144 {
 145         int ret = tdb_lockall_read(self->ctx);
 146         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 147         Py_RETURN_NONE;
 148 }
 149
 150 static PyObject *obj_unlockall_read(PyTdbObject *self)
 151 {
 152         int ret = tdb_unlockall_read(self->ctx);
 153         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 154         Py_RETURN_NONE;
 155 }
 156
 157 static PyObject *obj_close(PyTdbObject *self)
 158 {
 159         int ret;
 160         if (self->closed)
 161                 Py_RETURN_NONE;
 162         ret = tdb_close(self->ctx);
 163         self->closed = true;
 164         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 165         Py_RETURN_NONE;
 166 }
 167
 168 static PyObject *obj_get(PyTdbObject *self, PyObject *args)
 169 {
 170         TDB_DATA key;
 171         PyObject *py_key;
 172         if (!PyArg_ParseTuple(args, "O", &py_key))
 173                 return NULL;
 174
 175         key = PyString_AsTDB_DATA(py_key);
 176
 177         return PyString_FromTDB_DATA(tdb_fetch(self->ctx, key));
 178 }
 179
 180 static PyObject *obj_append(PyTdbObject *self, PyObject *args)
 181 {
 182         TDB_DATA key, data;
 183         PyObject *py_key, *py_data;
 184         int ret;
 185         if (!PyArg_ParseTuple(args, "OO", &py_key, &py_data))
 186                 return NULL;
 187
 188         key = PyString_AsTDB_DATA(py_key);
 189         data = PyString_AsTDB_DATA(py_data);
 190
 191         ret = tdb_append(self->ctx, key, data);
 192         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 193         Py_RETURN_NONE;
 194 }
 195
 196 static PyObject *obj_firstkey(PyTdbObject *self)
 197 {
 198         return PyString_FromTDB_DATA(tdb_firstkey(self->ctx));
 199 }
 200
 201 static PyObject *obj_nextkey(PyTdbObject *self, PyObject *args)
 202 {
 203         TDB_DATA key;
 204         PyObject *py_key;
 205         if (!PyArg_ParseTuple(args, "O", &py_key))
 206                 return NULL;
 207
 208         key = PyString_AsTDB_DATA(py_key);
 209
 210         return PyString_FromTDB_DATA(tdb_nextkey(self->ctx, key));
 211 }
 212
 213 static PyObject *obj_delete(PyTdbObject *self, PyObject *args)
 214 {
 215         TDB_DATA key;
 216         PyObject *py_key;
 217         int ret;
 218         if (!PyArg_ParseTuple(args, "O", &py_key))
 219                 return NULL;
 220
 221         key = PyString_AsTDB_DATA(py_key);
 222         ret = tdb_delete(self->ctx, key);
 223         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 224         Py_RETURN_NONE;
 225 }
 226
 227 static PyObject *obj_has_key(PyTdbObject *self, PyObject *args)
 228 {
 229         TDB_DATA key;
 230         int ret;
 231         PyObject *py_key;
 232         if (!PyArg_ParseTuple(args, "O", &py_key))
 233                 return NULL;
 234
 235         key = PyString_AsTDB_DATA(py_key);
 236         ret = tdb_exists(self->ctx, key);
 237         if (ret != TDB_ERR_NOEXIST) {
 238                 PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 239         }
 240
 241         return (ret == TDB_ERR_NOEXIST)?Py_False:Py_True;
 242 }
 243
 244 static PyObject *obj_store(PyTdbObject *self, PyObject *args)
 245 {
 246         TDB_DATA key, value;
 247         int ret;
 248         int flag = TDB_REPLACE;
 249         PyObject *py_key, *py_value;
 250
 251         if (!PyArg_ParseTuple(args, "OO|i", &py_key, &py_value, &flag))
 252                 return NULL;
 253
 254         key = PyString_AsTDB_DATA(py_key);
 255         value = PyString_AsTDB_DATA(py_value);
 256
 257         ret = tdb_store(self->ctx, key, value, flag);
 258         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 259         Py_RETURN_NONE;
 260 }
 261
 262 static PyObject *obj_add_flags(PyTdbObject *self, PyObject *args)
 263 {
 264         unsigned flags;
 265
 266         if (!PyArg_ParseTuple(args, "I", &flags))
 267                 return NULL;
 268
 269         tdb_add_flags(self->ctx, flags);
 270         Py_RETURN_NONE;
 271 }
 272
 273 static PyObject *obj_remove_flags(PyTdbObject *self, PyObject *args)
 274 {
 275         unsigned flags;
 276
 277         if (!PyArg_ParseTuple(args, "I", &flags))
 278                 return NULL;
 279
 280         tdb_remove_flags(self->ctx, flags);
 281         Py_RETURN_NONE;
 282 }
 283
 284 typedef struct {
 285         PyObject_HEAD
 286         TDB_DATA current;
 287         PyTdbObject *iteratee;
 288 } PyTdbIteratorObject;
 289
 290 static PyObject *tdb_iter_next(PyTdbIteratorObject *self)
 291 {
 292         TDB_DATA current;
 293         PyObject *ret;
 294         if (self->current.dptr == NULL && self->current.dsize == 0)
 295                 return NULL;
 296         current = self->current;
 297         self->current = tdb_nextkey(self->iteratee->ctx, self->current);
 298         ret = PyString_FromTDB_DATA(current);
 299         return ret;
 300 }
 301
 302 static void tdb_iter_dealloc(PyTdbIteratorObject *self)
 303 {
 304         Py_DECREF(self->iteratee);
 305         PyObject_Del(self);
 306 }
 307
 308 PyTypeObject PyTdbIterator = {
 309         .tp_name = "Iterator",
 310         .tp_basicsize = sizeof(PyTdbIteratorObject),
 311         .tp_iternext = (iternextfunc)tdb_iter_next,
 312         .tp_dealloc = (destructor)tdb_iter_dealloc,
 313         .tp_flags = Py_TPFLAGS_DEFAULT,
 314         .tp_iter = PyObject_SelfIter,
 315 };
 316
 317 static PyObject *tdb_object_iter(PyTdbObject *self)
 318 {
 319         PyTdbIteratorObject *ret;
 320
 321         ret = PyObject_New(PyTdbIteratorObject, &PyTdbIterator);
 322         ret->current = tdb_firstkey(self->ctx);
 323         ret->iteratee = self;
 324         Py_INCREF(self);
 325         return (PyObject *)ret;
 326 }
 327
 328 static PyObject *obj_clear(PyTdbObject *self)
 329 {
 330         int ret = tdb_wipe_all(self->ctx);
 331         PyErr_TDB_ERROR_IS_ERR_RAISE(ret, self->ctx);
 332         Py_RETURN_NONE;
 333 }
 334
 335 static PyMethodDef tdb_object_methods[] = {
 336         { "transaction_cancel", (PyCFunction)obj_transaction_cancel, METH_NOARGS,
 337                 "S.transaction_cancel() -> None\n"
 338                 "Cancel the currently active transaction." },
 339         { "transaction_commit", (PyCFunction)obj_transaction_commit, METH_NOARGS,
 340                 "S.transaction_commit() -> None\n"
 341                 "Commit the currently active transaction." },
 342         { "transaction_start", (PyCFunction)obj_transaction_start, METH_NOARGS,
 343                 "S.transaction_start() -> None\n"
 344                 "Start a new transaction." },
 345         { "reopen", (PyCFunction)obj_reopen, METH_NOARGS, "Reopen this file." },
 346         { "lock_all", (PyCFunction)obj_lockall, METH_NOARGS, NULL },
 347         { "unlock_all", (PyCFunction)obj_unlockall, METH_NOARGS, NULL },
 348         { "read_lock_all", (PyCFunction)obj_lockall_read, METH_NOARGS, NULL },
 349         { "read_unlock_all", (PyCFunction)obj_unlockall_read, METH_NOARGS, NULL },
 350         { "close", (PyCFunction)obj_close, METH_NOARGS, NULL },
 351         { "get", (PyCFunction)obj_get, METH_VARARGS, "S.get(key) -> value\n"
 352                 "Fetch a value." },
 353         { "append", (PyCFunction)obj_append, METH_VARARGS, "S.append(key, value) -> None\n"
 354                 "Append data to an existing key." },
 355         { "firstkey", (PyCFunction)obj_firstkey, METH_NOARGS, "S.firstkey() -> data\n"
 356                 "Return the first key in this database." },
 357         { "nextkey", (PyCFunction)obj_nextkey, METH_NOARGS, "S.nextkey(key) -> data\n"
 358                 "Return the next key in this database." },
 359         { "delete", (PyCFunction)obj_delete, METH_VARARGS, "S.delete(key) -> None\n"
 360                 "Delete an entry." },
 361         { "has_key", (PyCFunction)obj_has_key, METH_VARARGS, "S.has_key(key) -> None\n"
 362                 "Check whether key exists in this database." },
 363         { "store", (PyCFunction)obj_store, METH_VARARGS, "S.store(key, data, flag=REPLACE) -> None"
 364                 "Store data." },
 365         { "add_flags", (PyCFunction)obj_add_flags, METH_VARARGS, "S.add_flags(flags) -> None" },
 366         { "remove_flags", (PyCFunction)obj_remove_flags, METH_VARARGS, "S.remove_flags(flags) -> None" },
 367         { "iterkeys", (PyCFunction)tdb_object_iter, METH_NOARGS, "S.iterkeys() -> iterator" },
 368         { "clear", (PyCFunction)obj_clear, METH_NOARGS, "S.clear() -> None\n"
 369                 "Wipe the entire database." },
 370         { NULL }
 371 };
 372
 373 static PyObject *obj_get_hash_size(PyTdbObject *self, void *closure)
 374 {
 375         return PyInt_FromLong(tdb_hash_size(self->ctx));
 376 }
 377
 378 static int obj_set_max_dead(PyTdbObject *self, PyObject *max_dead, void *closure)
 379 {
 380         if (!PyInt_Check(max_dead))
 381                 return -1;
 382         tdb_set_max_dead(self->ctx, PyInt_AsLong(max_dead));
 383         return 0;
 384 }
 385
 386 static PyObject *obj_get_map_size(PyTdbObject *self, void *closure)
 387 {
 388         return PyInt_FromLong(tdb_map_size(self->ctx));
 389 }
 390
 391 static PyObject *obj_get_flags(PyTdbObject *self, void *closure)
 392 {
 393         return PyInt_FromLong(tdb_get_flags(self->ctx));
 394 }
 395
 396 static PyObject *obj_get_filename(PyTdbObject *self, void *closure)
 397 {
 398         return PyString_FromString(tdb_name(self->ctx));
 399 }
 400
 401 static PyGetSetDef tdb_object_getsetters[] = {
 402         { (char *)"hash_size", (getter)obj_get_hash_size, NULL, NULL },
 403         { (char *)"map_size", (getter)obj_get_map_size, NULL, NULL },
 404         { (char *)"flags", (getter)obj_get_flags, NULL, NULL },
 405         { (char *)"max_dead", NULL, (setter)obj_set_max_dead, NULL },
 406         { (char *)"filename", (getter)obj_get_filename, NULL, (char *)"The filename of this TDB file."},
 407         { NULL }
 408 };
 409
 410 static PyObject *tdb_object_repr(PyTdbObject *self)
 411 {
 412         return PyString_FromFormat("Tdb('%s')",
 413                 (tdb_get_flags(self->ctx) & TDB_INTERNAL) ? "<internal>"
 414                                                           : tdb_name(self->ctx));
 415 }
 416
 417 static void tdb_object_dealloc(PyTdbObject *self)
 418 {
 419         if (!self->closed)
 420                 tdb_close(self->ctx);
 421         PyObject_Del(self);
 422 }
 423
 424 static PyObject *obj_getitem(PyTdbObject *self, PyObject *key)
 425 {
 426         TDB_DATA tkey, val;
 427         if (!PyString_Check(key)) {
 428                 PyErr_SetString(PyExc_TypeError, "Expected string as key");
 429                 return NULL;
 430         }
 431
 432         tkey.dptr = (unsigned char *)PyString_AsString(key);
 433         tkey.dsize = PyString_Size(key);
 434
 435         val = tdb_fetch(self->ctx, tkey);
 436         if (val.dptr == NULL) {
 437                 PyErr_SetString(PyExc_KeyError, "No such TDB entry");
 438                 return NULL;
 439         } else {
 440                 return PyString_FromTDB_DATA(val);
 441         }
 442 }
 443
 444 static int obj_setitem(PyTdbObject *self, PyObject *key, PyObject *value)
 445 {
 446         TDB_DATA tkey, tval;
 447         int ret;
 448         if (!PyString_Check(key)) {
 449                 PyErr_SetString(PyExc_TypeError, "Expected string as key");
 450                 return -1;
 451         }
 452
 453         tkey = PyString_AsTDB_DATA(key);
 454
 455         if (value == NULL) {
 456                 ret = tdb_delete(self->ctx, tkey);
 457         } else {
 458                 if (!PyString_Check(value)) {
 459                         PyErr_SetString(PyExc_TypeError, "Expected string as value");
 460                         return -1;
 461                 }
 462
 463                 tval = PyString_AsTDB_DATA(value);
 464
 465                 ret = tdb_store(self->ctx, tkey, tval, TDB_REPLACE);
 466         }
 467
 468         if (ret != 0) {
 469                 PyErr_SetTDBError(self->ctx);
 470                 return -1;
 471         }
 472
 473         return ret;
 474 }
 475
 476 static PyMappingMethods tdb_object_mapping = {
 477         .mp_subscript = (binaryfunc)obj_getitem,
 478         .mp_ass_subscript = (objobjargproc)obj_setitem,
 479 };
 480 PyTypeObject PyTdb = {
 481         .tp_name = "Tdb",
 482         .tp_basicsize = sizeof(PyTdbObject),
 483         .tp_methods = tdb_object_methods,
 484         .tp_getset = tdb_object_getsetters,
 485         .tp_new = py_tdb_open,
 486         .tp_doc = "A TDB file",
 487         .tp_repr = (reprfunc)tdb_object_repr,
 488         .tp_dealloc = (destructor)tdb_object_dealloc,
 489         .tp_as_mapping = &tdb_object_mapping,
 490         .tp_flags = Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE|Py_TPFLAGS_HAVE_ITER,
 491         .tp_iter = (getiterfunc)tdb_object_iter,
 492 };
 493
 494 static PyMethodDef tdb_methods[] = {
 495         { "open", (PyCFunction)py_tdb_open, METH_VARARGS|METH_KEYWORDS, "open(name, hash_size=0, tdb_flags=TDB_DEFAULT, flags=O_RDWR, mode=0600)\n"
 496                 "Open a TDB file." },
 497         { NULL }
 498 };
 499
 500 void inittdb(void)
 501 {
 502         PyObject *m;
 503
 504         if (PyType_Ready(&PyTdb) < 0)
 505                 return;
 506
 507         if (PyType_Ready(&PyTdbIterator) < 0)
 508                 return;
 509
 510         m = Py_InitModule3("tdb", tdb_methods, "TDB is a simple key-value database similar to GDBM that supports multiple writers.");
 511         if (m == NULL)
 512                 return;
 513
 514         PyModule_AddObject(m, "REPLACE", PyInt_FromLong(TDB_REPLACE));
 515         PyModule_AddObject(m, "INSERT", PyInt_FromLong(TDB_INSERT));
 516         PyModule_AddObject(m, "MODIFY", PyInt_FromLong(TDB_MODIFY));
 517
 518         PyModule_AddObject(m, "DEFAULT", PyInt_FromLong(TDB_DEFAULT));
 519         PyModule_AddObject(m, "CLEAR_IF_FIRST", PyInt_FromLong(TDB_CLEAR_IF_FIRST));
 520         PyModule_AddObject(m, "INTERNAL", PyInt_FromLong(TDB_INTERNAL));
 521         PyModule_AddObject(m, "NOLOCK", PyInt_FromLong(TDB_NOLOCK));
 522         PyModule_AddObject(m, "NOMMAP", PyInt_FromLong(TDB_NOMMAP));
 523         PyModule_AddObject(m, "CONVERT", PyInt_FromLong(TDB_CONVERT));
 524         PyModule_AddObject(m, "BIGENDIAN", PyInt_FromLong(TDB_BIGENDIAN));
 525         PyModule_AddObject(m, "__docformat__", PyString_FromString("restructuredText"));
 526
 527         Py_INCREF(&PyTdb);
 528         PyModule_AddObject(m, "Tdb", (PyObject *)&PyTdb);
 529
 530         Py_INCREF(&PyTdbIterator);
 531 }