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
  38 PyObject* 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
  42 PyObject* converters;
  43 int _enable_callback_tracebacks;
  44 int pysqlite_BaseTypeAdapted;
  45
  46 static 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
  79 PyDoc_STRVAR(module_connect_doc,
  80 "connect(database[, timeout, isolation_level, detect_types, factory])\n\
  81 \n\
  82 Opens 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\
  84 RAM instead of on disk.");
  85
  86 static 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
 110 PyDoc_STRVAR(module_complete_doc,
 111 "complete_statement(sql)\n\
 112 \n\
 113 Checks if a string contains a complete SQL statement. Non-standard.");
 114
 115 #ifdef HAVE_SHARED_CACHE
 116 static 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
 139 PyDoc_STRVAR(module_enable_shared_cache_doc,
 140 "enable_shared_cache(do_enable)\n\
 141 \n\
 142 Enable or disable shared cache mode for the calling thread.\n\
 143 Experimental/Non-standard.");
 144 #endif /* HAVE_SHARED_CACHE */
 145
 146 static 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
 171 PyDoc_STRVAR(module_register_adapter_doc,
 172 "register_adapter(type, callable)\n\
 173 \n\
 174 Registers an adapter with pysqlite's adapter registry. Non-standard.");
 175
 176 static 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;
 199 error:
 200     Py_XDECREF(name);
 201     return retval;
 202 }
 203
 204 PyDoc_STRVAR(module_register_converter_doc,
 205 "register_converter(typename, callable)\n\
 206 \n\
 207 Registers a converter with pysqlite. Non-standard.");
 208
 209 static 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
 219 PyDoc_STRVAR(enable_callback_tracebacks_doc,
 220 "enable_callback_tracebacks(flag)\n\
 221 \n\
 222 Enable or disable callback functions throwing errors to stderr.");
 223
 224 static 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
 234 static 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
 254 struct _IntConstantPair {
 255     char* constant_name;
 256     int constant_value;
 257 };
 258
 259 typedef struct _IntConstantPair IntConstantPair;
 260
 261 static 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
 303 PyMODINIT_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
 452 error:
 453     if (PyErr_Occurred())
 454     {
 455         PyErr_SetString(PyExc_ImportError, MODULE_NAME ": init failed");
 456     }
 457 }