/Modules/_sqlite/module.c

  1/* module.c - the module itself
  2 *
  3 * Copyright (C) 2004-2007 Gerhard Häring <gh@ghaering.de>
  4 *
  5 * This file is part of pysqlite.
  6 *
  7 * This software is provided 'as-is', without any express or implied
  8 * warranty.  In no event will the authors be held liable for any damages
  9 * arising from the use of this software.
 10 *
 11 * Permission is granted to anyone to use this software for any purpose,
 12 * including commercial applications, and to alter it and redistribute it
 13 * freely, subject to the following restrictions:
 14 *
 15 * 1. The origin of this software must not be misrepresented; you must not
 16 *    claim that you wrote the original software. If you use this software
 17 *    in a product, an acknowledgment in the product documentation would be
 18 *    appreciated but is not required.
 19 * 2. Altered source versions must be plainly marked as such, and must not be
 20 *    misrepresented as being the original software.
 21 * 3. This notice may not be removed or altered from any source distribution.
 22 */
 23
 24#include "connection.h"
 25#include "statement.h"
 26#include "cursor.h"
 27#include "cache.h"
 28#include "prepare_protocol.h"
 29#include "microprotocols.h"
 30#include "row.h"
 31
 32#if SQLITE_VERSION_NUMBER >= 3003003
 33#define HAVE_SHARED_CACHE
 34#endif
 35
 36/* static objects at module-level */
 37
 38PyObject* pysqlite_Error, *pysqlite_Warning, *pysqlite_InterfaceError, *pysqlite_DatabaseError,
 39    *pysqlite_InternalError, *pysqlite_OperationalError, *pysqlite_ProgrammingError,
 40    *pysqlite_IntegrityError, *pysqlite_DataError, *pysqlite_NotSupportedError, *pysqlite_OptimizedUnicode;
 41
 42PyObject* converters;
 43int _enable_callback_tracebacks;
 44int pysqlite_BaseTypeAdapted;
 45
 46static PyObject* module_connect(PyObject* self, PyObject* args, PyObject*
 47        kwargs)
 48{
 49    /* Python seems to have no way of extracting a single keyword-arg at
 50     * C-level, so this code is redundant with the one in connection_init in
 51     * connection.c and must always be copied from there ... */
 52
 53    static char *kwlist[] = {"database", "timeout", "detect_types", "isolation_level", "check_same_thread", "factory", "cached_statements", NULL, NULL};
 54    PyObject* database;
 55    int detect_types = 0;
 56    PyObject* isolation_level;
 57    PyObject* factory = NULL;
 58    int check_same_thread = 1;
 59    int cached_statements;
 60    double timeout = 5.0;
 61
 62    PyObject* result;
 63
 64    if (!PyArg_ParseTupleAndKeywords(args, kwargs, "O|diOiOi", kwlist,
 65                                     &database, &timeout, &detect_types, &isolation_level, &check_same_thread, &factory, &cached_statements))
 66    {
 67        return NULL; 
 68    }
 69
 70    if (factory == NULL) {
 71        factory = (PyObject*)&pysqlite_ConnectionType;
 72    }
 73
 74    result = PyObject_Call(factory, args, kwargs);
 75
 76    return result;
 77}
 78
 79PyDoc_STRVAR(module_connect_doc,
 80"connect(database[, timeout, isolation_level, detect_types, factory])\n\
 81\n\
 82Opens a connection to the SQLite database file *database*. You can use\n\
 83\":memory:\" to open a database connection to a database that resides in\n\
 84RAM instead of on disk.");
 85
 86static PyObject* module_complete(PyObject* self, PyObject* args, PyObject*
 87        kwargs)
 88{
 89    static char *kwlist[] = {"statement", NULL, NULL};
 90    char* statement;
 91
 92    PyObject* result;
 93
 94    if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s", kwlist, &statement))
 95    {
 96        return NULL; 
 97    }
 98
 99    if (sqlite3_complete(statement)) {
100        result = Py_True;
101    } else {
102        result = Py_False;
103    }
104
105    Py_INCREF(result);
106
107    return result;
108}
109
110PyDoc_STRVAR(module_complete_doc,
111"complete_statement(sql)\n\
112\n\
113Checks if a string contains a complete SQL statement. Non-standard.");
114
115#ifdef HAVE_SHARED_CACHE
116static PyObject* module_enable_shared_cache(PyObject* self, PyObject* args, PyObject*
117        kwargs)
118{
119    static char *kwlist[] = {"do_enable", NULL, NULL};
120    int do_enable;
121    int rc;
122
123    if (!PyArg_ParseTupleAndKeywords(args, kwargs, "i", kwlist, &do_enable))
124    {
125        return NULL; 
126    }
127
128    rc = sqlite3_enable_shared_cache(do_enable);
129
130    if (rc != SQLITE_OK) {
131        PyErr_SetString(pysqlite_OperationalError, "Changing the shared_cache flag failed");
132        return NULL;
133    } else {
134        Py_INCREF(Py_None);
135        return Py_None;
136    }
137}
138
139PyDoc_STRVAR(module_enable_shared_cache_doc,
140"enable_shared_cache(do_enable)\n\
141\n\
142Enable or disable shared cache mode for the calling thread.\n\
143Experimental/Non-standard.");
144#endif /* HAVE_SHARED_CACHE */
145
146static PyObject* module_register_adapter(PyObject* self, PyObject* args)
147{
148    PyTypeObject* type;
149    PyObject* caster;
150    int rc;
151
152    if (!PyArg_ParseTuple(args, "OO", &type, &caster)) {
153        return NULL;
154    }
155
156    /* a basic type is adapted; there's a performance optimization if that's not the case
157     * (99 % of all usages) */
158    if (type == &PyInt_Type || type == &PyLong_Type || type == &PyFloat_Type
159            || type == &PyString_Type || type == &PyUnicode_Type || type == &PyBuffer_Type) {
160        pysqlite_BaseTypeAdapted = 1;
161    }
162
163    rc = pysqlite_microprotocols_add(type, (PyObject*)&pysqlite_PrepareProtocolType, caster);
164    if (rc == -1)
165        return NULL;
166
167    Py_INCREF(Py_None);
168    return Py_None;
169}
170
171PyDoc_STRVAR(module_register_adapter_doc,
172"register_adapter(type, callable)\n\
173\n\
174Registers an adapter with pysqlite's adapter registry. Non-standard.");
175
176static PyObject* module_register_converter(PyObject* self, PyObject* args)
177{
178    PyObject* orig_name;
179    PyObject* name = NULL;
180    PyObject* callable;
181    PyObject* retval = NULL;
182
183    if (!PyArg_ParseTuple(args, "SO", &orig_name, &callable)) {
184        return NULL;
185    }
186
187    /* convert the name to upper case */
188    name = PyObject_CallMethod(orig_name, "upper", "");
189    if (!name) {
190        goto error;
191    }
192
193    if (PyDict_SetItem(converters, name, callable) != 0) {
194        goto error;
195    }
196
197    Py_INCREF(Py_None);
198    retval = Py_None;
199error:
200    Py_XDECREF(name);
201    return retval;
202}
203
204PyDoc_STRVAR(module_register_converter_doc,
205"register_converter(typename, callable)\n\
206\n\
207Registers a converter with pysqlite. Non-standard.");
208
209static PyObject* enable_callback_tracebacks(PyObject* self, PyObject* args)
210{
211    if (!PyArg_ParseTuple(args, "i", &_enable_callback_tracebacks)) {
212        return NULL;
213    }
214
215    Py_INCREF(Py_None);
216    return Py_None;
217}
218
219PyDoc_STRVAR(enable_callback_tracebacks_doc,
220"enable_callback_tracebacks(flag)\n\
221\n\
222Enable or disable callback functions throwing errors to stderr.");
223
224static void converters_init(PyObject* dict)
225{
226    converters = PyDict_New();
227    if (!converters) {
228        return;
229    }
230
231    PyDict_SetItemString(dict, "converters", converters);
232}
233
234static PyMethodDef module_methods[] = {
235    {"connect",  (PyCFunction)module_connect,
236     METH_VARARGS | METH_KEYWORDS, module_connect_doc},
237    {"complete_statement",  (PyCFunction)module_complete,
238     METH_VARARGS | METH_KEYWORDS, module_complete_doc},
239#ifdef HAVE_SHARED_CACHE
240    {"enable_shared_cache",  (PyCFunction)module_enable_shared_cache,
241     METH_VARARGS | METH_KEYWORDS, module_enable_shared_cache_doc},
242#endif
243    {"register_adapter", (PyCFunction)module_register_adapter,
244     METH_VARARGS, module_register_adapter_doc},
245    {"register_converter", (PyCFunction)module_register_converter,
246     METH_VARARGS, module_register_converter_doc},
247    {"adapt",  (PyCFunction)pysqlite_adapt, METH_VARARGS,
248     pysqlite_adapt_doc},
249    {"enable_callback_tracebacks",  (PyCFunction)enable_callback_tracebacks,
250     METH_VARARGS, enable_callback_tracebacks_doc},
251    {NULL, NULL}
252};
253
254struct _IntConstantPair {
255    char* constant_name;
256    int constant_value;
257};
258
259typedef struct _IntConstantPair IntConstantPair;
260
261static IntConstantPair _int_constants[] = {
262    {"PARSE_DECLTYPES", PARSE_DECLTYPES},
263    {"PARSE_COLNAMES", PARSE_COLNAMES},
264
265    {"SQLITE_OK", SQLITE_OK},
266    {"SQLITE_DENY", SQLITE_DENY},
267    {"SQLITE_IGNORE", SQLITE_IGNORE},
268    {"SQLITE_CREATE_INDEX", SQLITE_CREATE_INDEX},
269    {"SQLITE_CREATE_TABLE", SQLITE_CREATE_TABLE},
270    {"SQLITE_CREATE_TEMP_INDEX", SQLITE_CREATE_TEMP_INDEX},
271    {"SQLITE_CREATE_TEMP_TABLE", SQLITE_CREATE_TEMP_TABLE},
272    {"SQLITE_CREATE_TEMP_TRIGGER", SQLITE_CREATE_TEMP_TRIGGER},
273    {"SQLITE_CREATE_TEMP_VIEW", SQLITE_CREATE_TEMP_VIEW},
274    {"SQLITE_CREATE_TRIGGER", SQLITE_CREATE_TRIGGER},
275    {"SQLITE_CREATE_VIEW", SQLITE_CREATE_VIEW},
276    {"SQLITE_DELETE", SQLITE_DELETE},
277    {"SQLITE_DROP_INDEX", SQLITE_DROP_INDEX},
278    {"SQLITE_DROP_TABLE", SQLITE_DROP_TABLE},
279    {"SQLITE_DROP_TEMP_INDEX", SQLITE_DROP_TEMP_INDEX},
280    {"SQLITE_DROP_TEMP_TABLE", SQLITE_DROP_TEMP_TABLE},
281    {"SQLITE_DROP_TEMP_TRIGGER", SQLITE_DROP_TEMP_TRIGGER},
282    {"SQLITE_DROP_TEMP_VIEW", SQLITE_DROP_TEMP_VIEW},
283    {"SQLITE_DROP_TRIGGER", SQLITE_DROP_TRIGGER},
284    {"SQLITE_DROP_VIEW", SQLITE_DROP_VIEW},
285    {"SQLITE_INSERT", SQLITE_INSERT},
286    {"SQLITE_PRAGMA", SQLITE_PRAGMA},
287    {"SQLITE_READ", SQLITE_READ},
288    {"SQLITE_SELECT", SQLITE_SELECT},
289    {"SQLITE_TRANSACTION", SQLITE_TRANSACTION},
290    {"SQLITE_UPDATE", SQLITE_UPDATE},
291    {"SQLITE_ATTACH", SQLITE_ATTACH},
292    {"SQLITE_DETACH", SQLITE_DETACH},
293#if SQLITE_VERSION_NUMBER >= 3002001
294    {"SQLITE_ALTER_TABLE", SQLITE_ALTER_TABLE},
295    {"SQLITE_REINDEX", SQLITE_REINDEX},
296#endif
297#if SQLITE_VERSION_NUMBER >= 3003000
298    {"SQLITE_ANALYZE", SQLITE_ANALYZE},
299#endif
300    {(char*)NULL, 0}
301};
302
303PyMODINIT_FUNC init_sqlite3(void)
304{
305    PyObject *module, *dict;
306    PyObject *tmp_obj;
307    int i;
308
309    module = Py_InitModule("_sqlite3", module_methods);
310
311    if (!module ||
312        (pysqlite_row_setup_types() < 0) ||
313        (pysqlite_cursor_setup_types() < 0) ||
314        (pysqlite_connection_setup_types() < 0) ||
315        (pysqlite_cache_setup_types() < 0) ||
316        (pysqlite_statement_setup_types() < 0) ||
317        (pysqlite_prepare_protocol_setup_types() < 0)
318       ) {
319        return;
320    }
321
322    Py_INCREF(&pysqlite_ConnectionType);
323    PyModule_AddObject(module, "Connection", (PyObject*) &pysqlite_ConnectionType);
324    Py_INCREF(&pysqlite_CursorType);
325    PyModule_AddObject(module, "Cursor", (PyObject*) &pysqlite_CursorType);
326    Py_INCREF(&pysqlite_CacheType);
327    PyModule_AddObject(module, "Statement", (PyObject*)&pysqlite_StatementType);
328    Py_INCREF(&pysqlite_StatementType);
329    PyModule_AddObject(module, "Cache", (PyObject*) &pysqlite_CacheType);
330    Py_INCREF(&pysqlite_PrepareProtocolType);
331    PyModule_AddObject(module, "PrepareProtocol", (PyObject*) &pysqlite_PrepareProtocolType);
332    Py_INCREF(&pysqlite_RowType);
333    PyModule_AddObject(module, "Row", (PyObject*) &pysqlite_RowType);
334
335    if (!(dict = PyModule_GetDict(module))) {
336        goto error;
337    }
338
339    /*** Create DB-API Exception hierarchy */
340
341    if (!(pysqlite_Error = PyErr_NewException(MODULE_NAME ".Error", PyExc_StandardError, NULL))) {
342        goto error;
343    }
344    PyDict_SetItemString(dict, "Error", pysqlite_Error);
345
346    if (!(pysqlite_Warning = PyErr_NewException(MODULE_NAME ".Warning", PyExc_StandardError, NULL))) {
347        goto error;
348    }
349    PyDict_SetItemString(dict, "Warning", pysqlite_Warning);
350
351    /* Error subclasses */
352
353    if (!(pysqlite_InterfaceError = PyErr_NewException(MODULE_NAME ".InterfaceError", pysqlite_Error, NULL))) {
354        goto error;
355    }
356    PyDict_SetItemString(dict, "InterfaceError", pysqlite_InterfaceError);
357
358    if (!(pysqlite_DatabaseError = PyErr_NewException(MODULE_NAME ".DatabaseError", pysqlite_Error, NULL))) {
359        goto error;
360    }
361    PyDict_SetItemString(dict, "DatabaseError", pysqlite_DatabaseError);
362
363    /* pysqlite_DatabaseError subclasses */
364
365    if (!(pysqlite_InternalError = PyErr_NewException(MODULE_NAME ".InternalError", pysqlite_DatabaseError, NULL))) {
366        goto error;
367    }
368    PyDict_SetItemString(dict, "InternalError", pysqlite_InternalError);
369
370    if (!(pysqlite_OperationalError = PyErr_NewException(MODULE_NAME ".OperationalError", pysqlite_DatabaseError, NULL))) {
371        goto error;
372    }
373    PyDict_SetItemString(dict, "OperationalError", pysqlite_OperationalError);
374
375    if (!(pysqlite_ProgrammingError = PyErr_NewException(MODULE_NAME ".ProgrammingError", pysqlite_DatabaseError, NULL))) {
376        goto error;
377    }
378    PyDict_SetItemString(dict, "ProgrammingError", pysqlite_ProgrammingError);
379
380    if (!(pysqlite_IntegrityError = PyErr_NewException(MODULE_NAME ".IntegrityError", pysqlite_DatabaseError,NULL))) {
381        goto error;
382    }
383    PyDict_SetItemString(dict, "IntegrityError", pysqlite_IntegrityError);
384
385    if (!(pysqlite_DataError = PyErr_NewException(MODULE_NAME ".DataError", pysqlite_DatabaseError, NULL))) {
386        goto error;
387    }
388    PyDict_SetItemString(dict, "DataError", pysqlite_DataError);
389
390    if (!(pysqlite_NotSupportedError = PyErr_NewException(MODULE_NAME ".NotSupportedError", pysqlite_DatabaseError, NULL))) {
391        goto error;
392    }
393    PyDict_SetItemString(dict, "NotSupportedError", pysqlite_NotSupportedError);
394
395    /* We just need "something" unique for pysqlite_OptimizedUnicode. It does not really
396     * need to be a string subclass. Just anything that can act as a special
397     * marker for us. So I pulled PyCell_Type out of my magic hat.
398     */
399    Py_INCREF((PyObject*)&PyCell_Type);
400    pysqlite_OptimizedUnicode = (PyObject*)&PyCell_Type;
401    PyDict_SetItemString(dict, "OptimizedUnicode", pysqlite_OptimizedUnicode);
402
403    /* Set integer constants */
404    for (i = 0; _int_constants[i].constant_name != 0; i++) {
405        tmp_obj = PyInt_FromLong(_int_constants[i].constant_value);
406        if (!tmp_obj) {
407            goto error;
408        }
409        PyDict_SetItemString(dict, _int_constants[i].constant_name, tmp_obj);
410        Py_DECREF(tmp_obj);
411    }
412
413    if (!(tmp_obj = PyString_FromString(PYSQLITE_VERSION))) {
414        goto error;
415    }
416    PyDict_SetItemString(dict, "version", tmp_obj);
417    Py_DECREF(tmp_obj);
418
419    if (!(tmp_obj = PyString_FromString(sqlite3_libversion()))) {
420        goto error;
421    }
422    PyDict_SetItemString(dict, "sqlite_version", tmp_obj);
423    Py_DECREF(tmp_obj);
424
425    /* initialize microprotocols layer */
426    pysqlite_microprotocols_init(dict);
427
428    /* initialize the default converters */
429    converters_init(dict);
430
431    _enable_callback_tracebacks = 0;
432
433    pysqlite_BaseTypeAdapted = 0;
434
435    /* Original comment from _bsddb.c in the Python core. This is also still
436     * needed nowadays for Python 2.3/2.4.
437     * 
438     * PyEval_InitThreads is called here due to a quirk in python 1.5
439     * - 2.2.1 (at least) according to Russell Williamson <merel@wt.net>:
440     * The global interpreter lock is not initialized until the first
441     * thread is created using thread.start_new_thread() or fork() is
442     * called.  that would cause the ALLOW_THREADS here to segfault due
443     * to a null pointer reference if no threads or child processes
444     * have been created.  This works around that and is a no-op if
445     * threads have already been initialized.
446     *  (see pybsddb-users mailing list post on 2002-08-07)
447     */
448#ifdef WITH_THREAD
449    PyEval_InitThreads();
450#endif
451
452error:
453    if (PyErr_Occurred())
454    {
455        PyErr_SetString(PyExc_ImportError, MODULE_NAME ": init failed");
456    }
457}