/* DBM module using dictionary interface */ // clinic/_dbmmodule.c.h uses internal pycore_modsupport.h API #ifndef Py_BUILD_CORE_BUILTIN # define Py_BUILD_CORE_MODULE 1 #endif #include "Python.h" #include "pycore_object.h" // _PyObject_VisitType() #include #include #include /* Some Linux systems install gdbm/ndbm.h, but not ndbm.h. This supports * whichever configure was able to locate. */ #if defined(USE_GDBM_COMPAT) #ifdef HAVE_GDBM_NDBM_H #include #elif HAVE_GDBM_DASH_NDBM_H #include #else #error "No gdbm/ndbm.h or gdbm-ndbm.h available" #endif static const char which_dbm[] = "GNU gdbm"; #elif defined(USE_NDBM) #include #ifdef _GDBM_H_ /* ndbm.h is the GDBM compatibility interface. */ static const char which_dbm[] = "GNU gdbm"; #else static const char which_dbm[] = "ndbm"; #endif #elif defined(USE_BERKDB) #ifndef DB_DBM_HSEARCH #define DB_DBM_HSEARCH 1 #endif #include static const char which_dbm[] = "Berkeley DB"; #else #error "No ndbm.h available!" #endif typedef struct { PyTypeObject *dbm_type; PyObject *dbm_error; } _dbm_state; static inline _dbm_state* get_dbm_state(PyObject *module) { void *state = PyModule_GetState(module); assert(state != NULL); return (_dbm_state *)state; } /*[clinic input] module _dbm class _dbm.dbm "dbmobject *" "&Dbmtype" [clinic start generated code]*/ /*[clinic end generated code: output=da39a3ee5e6b4b0d input=9b1aa8756d16150e]*/ typedef struct { PyObject_HEAD int flags; int di_size; /* -1 means recompute */ DBM *di_dbm; } dbmobject; #define dbmobject_CAST(op) ((dbmobject *)(op)) #include "clinic/_dbmmodule.c.h" #define check_dbmobject_open(v, err) \ _Py_CRITICAL_SECTION_ASSERT_OBJECT_LOCKED((v)) \ if ((v)->di_dbm == NULL) { \ PyErr_SetString(err, "DBM object has already been closed"); \ return NULL; \ } static PyObject * newdbmobject(_dbm_state *state, const char *file, int flags, int mode) { dbmobject *dp = PyObject_GC_New(dbmobject, state->dbm_type); if (dp == NULL) { return NULL; } dp->di_size = -1; dp->flags = flags; PyObject_GC_Track(dp); /* See issue #19296 */ if ( (dp->di_dbm = dbm_open((char *)file, flags, mode)) == 0 ) { PyErr_SetFromErrnoWithFilename(state->dbm_error, file); Py_DECREF(dp); return NULL; } return (PyObject *)dp; } /* Methods */ static void dbm_dealloc(PyObject *self) { dbmobject *dp = dbmobject_CAST(self); PyObject_GC_UnTrack(dp); if (dp->di_dbm) { dbm_close(dp->di_dbm); } PyTypeObject *tp = Py_TYPE(dp); tp->tp_free(dp); Py_DECREF(tp); } /*[clinic input] @critical_section _dbm.dbm.__len__ as dbm_length [clinic start generated code]*/ static Py_ssize_t dbm_length_impl(dbmobject *self) /*[clinic end generated code: output=d7ea9510562e5f86 input=f912d65e9b06fef5]*/ { dbmobject *dp = self; _dbm_state *state = PyType_GetModuleState(Py_TYPE(dp)); assert(state != NULL); if (dp->di_dbm == NULL) { PyErr_SetString(state->dbm_error, "DBM object has already been closed"); return -1; } if ( dp->di_size < 0 ) { datum key; int size; size = 0; for ( key=dbm_firstkey(dp->di_dbm); key.dptr; key = dbm_nextkey(dp->di_dbm)) size++; dp->di_size = size; } return dp->di_size; } /*[clinic input] @critical_section _dbm.dbm.__bool__ as dbm_bool [clinic start generated code]*/ static int dbm_bool_impl(dbmobject *self) /*[clinic end generated code: output=b550ce1ae52d6ad1 input=212af765b6e60719]*/ { dbmobject *dp = self; _dbm_state *state = PyType_GetModuleState(Py_TYPE(dp)); assert(state != NULL); if (dp->di_dbm == NULL) { PyErr_SetString(state->dbm_error, "DBM object has already been closed"); return -1; } if (dp->di_size > 0) { /* Known non-zero size. */ return 1; } if (dp->di_size == 0) { /* Known zero size. */ return 0; } /* Unknown size. Ensure DBM object has an entry. */ datum key = dbm_firstkey(dp->di_dbm); if (key.dptr == NULL) { /* Empty. Cache this fact. */ dp->di_size = 0; return 0; } /* Non-empty. Don't cache the length since we don't know. */ return 1; } /*[clinic input] @critical_section _dbm.dbm.__getitem__ as dbm_subscript key: object / [clinic start generated code]*/ static PyObject * dbm_subscript_impl(dbmobject *self, PyObject *key) /*[clinic end generated code: output=6278465f3ff37eaa input=e748b684a0870527]*/ { datum drec, krec; Py_ssize_t tmp_size; dbmobject *dp = self; _dbm_state *state = PyType_GetModuleState(Py_TYPE(dp)); assert(state != NULL); if (!PyArg_Parse(key, "s#", &krec.dptr, &tmp_size)) { return NULL; } krec.dsize = tmp_size; check_dbmobject_open(dp, state->dbm_error); drec = dbm_fetch(dp->di_dbm, krec); if ( drec.dptr == 0 ) { PyErr_SetObject(PyExc_KeyError, key); return NULL; } if ( dbm_error(dp->di_dbm) ) { dbm_clearerr(dp->di_dbm); PyErr_SetString(state->dbm_error, ""); return NULL; } return PyBytes_FromStringAndSize(drec.dptr, drec.dsize); } /*[clinic input] @critical_section _dbm.dbm.__setitem__ as dbm_ass_sub v: object w: object / [clinic start generated code]*/ static int dbm_ass_sub_impl(dbmobject *self, PyObject *v, PyObject *w) /*[clinic end generated code: output=33e861810d1fd44a input=4f10cc93a02142ee]*/ { datum krec, drec; Py_ssize_t tmp_size; dbmobject *dp = self; if ( !PyArg_Parse(v, "s#", &krec.dptr, &tmp_size) ) { PyErr_SetString(PyExc_TypeError, "dbm mappings have bytes or string keys only"); return -1; } _dbm_state *state = PyType_GetModuleState(Py_TYPE(dp)); assert(state != NULL); krec.dsize = tmp_size; if (dp->di_dbm == NULL) { PyErr_SetString(state->dbm_error, "DBM object has already been closed"); return -1; } dp->di_size = -1; if (w == NULL) { if ( dbm_delete(dp->di_dbm, krec) < 0 ) { dbm_clearerr(dp->di_dbm); /* we might get a failure for reasons like file corrupted, but we are not able to distinguish it */ if (dp->flags & O_RDWR) { PyErr_SetObject(PyExc_KeyError, v); } else { PyErr_SetString(state->dbm_error, "cannot delete item from database"); } return -1; } } else { if ( !PyArg_Parse(w, "s#", &drec.dptr, &tmp_size) ) { PyErr_SetString(PyExc_TypeError, "dbm mappings have bytes or string elements only"); return -1; } drec.dsize = tmp_size; if ( dbm_store(dp->di_dbm, krec, drec, DBM_REPLACE) < 0 ) { dbm_clearerr(dp->di_dbm); PyErr_SetString(state->dbm_error, "cannot add item to database"); return -1; } } if ( dbm_error(dp->di_dbm) ) { dbm_clearerr(dp->di_dbm); PyErr_SetString(state->dbm_error, ""); return -1; } return 0; } /*[clinic input] @critical_section _dbm.dbm.close Close the database. [clinic start generated code]*/ static PyObject * _dbm_dbm_close_impl(dbmobject *self) /*[clinic end generated code: output=c8dc5b6709600b86 input=4a94f79facbc28ca]*/ { if (self->di_dbm) { dbm_close(self->di_dbm); } self->di_dbm = NULL; Py_RETURN_NONE; } /*[clinic input] @critical_section _dbm.dbm.keys cls: defining_class Return a list of all keys in the database. [clinic start generated code]*/ static PyObject * _dbm_dbm_keys_impl(dbmobject *self, PyTypeObject *cls) /*[clinic end generated code: output=f2a593b3038e5996 input=6ddefeadf2a80156]*/ { PyObject *v, *item; datum key; int err; _dbm_state *state = PyType_GetModuleState(cls); assert(state != NULL); check_dbmobject_open(self, state->dbm_error); v = PyList_New(0); if (v == NULL) { return NULL; } for (key = dbm_firstkey(self->di_dbm); key.dptr; key = dbm_nextkey(self->di_dbm)) { item = PyBytes_FromStringAndSize(key.dptr, key.dsize); if (item == NULL) { Py_DECREF(v); return NULL; } err = PyList_Append(v, item); Py_DECREF(item); if (err != 0) { Py_DECREF(v); return NULL; } } return v; } /*[clinic input] @critical_section _dbm.dbm.__contains__ as dbm_contains arg: object / [clinic start generated code]*/ static int dbm_contains_impl(dbmobject *self, PyObject *arg) /*[clinic end generated code: output=6c42b797ada528bc input=94134e7abf3eeb6e]*/ { dbmobject *dp = self; datum key, val; Py_ssize_t size; _dbm_state *state = PyType_GetModuleState(Py_TYPE(dp)); assert(state != NULL); if ((dp)->di_dbm == NULL) { PyErr_SetString(state->dbm_error, "DBM object has already been closed"); return -1; } if (PyUnicode_Check(arg)) { key.dptr = (char *)PyUnicode_AsUTF8AndSize(arg, &size); key.dsize = size; if (key.dptr == NULL) return -1; } else if (!PyBytes_Check(arg)) { PyErr_Format(PyExc_TypeError, "dbm key must be bytes or string, not %.100s", Py_TYPE(arg)->tp_name); return -1; } else { key.dptr = PyBytes_AS_STRING(arg); key.dsize = PyBytes_GET_SIZE(arg); } val = dbm_fetch(dp->di_dbm, key); return val.dptr != NULL; } /*[clinic input] @critical_section _dbm.dbm.get cls: defining_class key: str(accept={str, robuffer}, zeroes=True) default: object = None / Return the value for key if present, otherwise default. [clinic start generated code]*/ static PyObject * _dbm_dbm_get_impl(dbmobject *self, PyTypeObject *cls, const char *key, Py_ssize_t key_length, PyObject *default_value) /*[clinic end generated code: output=b4e55f8b6d482bc4 input=1d88a22bb5e55202]*/ { datum dbm_key, val; _dbm_state *state = PyType_GetModuleState(cls); assert(state != NULL); dbm_key.dptr = (char *)key; dbm_key.dsize = key_length; check_dbmobject_open(self, state->dbm_error); val = dbm_fetch(self->di_dbm, dbm_key); if (val.dptr != NULL) { return PyBytes_FromStringAndSize(val.dptr, val.dsize); } return Py_NewRef(default_value); } /*[clinic input] @critical_section _dbm.dbm.setdefault cls: defining_class key: str(accept={str, robuffer}, zeroes=True) default: object(c_default="NULL") = b'' / Return the value for key if present, otherwise default. If key is not in the database, it is inserted with default as the value. [clinic start generated code]*/ static PyObject * _dbm_dbm_setdefault_impl(dbmobject *self, PyTypeObject *cls, const char *key, Py_ssize_t key_length, PyObject *default_value) /*[clinic end generated code: output=9c2f6ea6d0fb576c input=81224965c110f830]*/ { datum dbm_key, val; Py_ssize_t tmp_size; _dbm_state *state = PyType_GetModuleState(cls); assert(state != NULL); dbm_key.dptr = (char *)key; dbm_key.dsize = key_length; check_dbmobject_open(self, state->dbm_error); val = dbm_fetch(self->di_dbm, dbm_key); if (val.dptr != NULL) { return PyBytes_FromStringAndSize(val.dptr, val.dsize); } if (default_value == NULL) { default_value = Py_GetConstant(Py_CONSTANT_EMPTY_BYTES); val.dptr = NULL; val.dsize = 0; } else { if ( !PyArg_Parse(default_value, "s#", &val.dptr, &tmp_size) ) { PyErr_SetString(PyExc_TypeError, "dbm mappings have bytes or string elements only"); return NULL; } val.dsize = tmp_size; Py_INCREF(default_value); } if (dbm_store(self->di_dbm, dbm_key, val, DBM_INSERT) < 0) { dbm_clearerr(self->di_dbm); PyErr_SetString(state->dbm_error, "cannot add item to database"); Py_DECREF(default_value); return NULL; } return default_value; } /*[clinic input] @critical_section _dbm.dbm.clear cls: defining_class / Remove all items from the database. [clinic start generated code]*/ static PyObject * _dbm_dbm_clear_impl(dbmobject *self, PyTypeObject *cls) /*[clinic end generated code: output=8d126b9e1d01a434 input=a1aa5d99adfb9656]*/ { _dbm_state *state = PyType_GetModuleState(cls); assert(state != NULL); check_dbmobject_open(self, state->dbm_error); datum key; // Invalidate cache self->di_size = -1; while (1) { key = dbm_firstkey(self->di_dbm); if (key.dptr == NULL) { break; } if (dbm_delete(self->di_dbm, key) < 0) { dbm_clearerr(self->di_dbm); PyErr_SetString(state->dbm_error, "cannot delete item from database"); return NULL; } } Py_RETURN_NONE; } static PyObject * dbm__enter__(PyObject *self, PyObject *Py_UNUSED(dummy)) { return Py_NewRef(self); } /*[clinic input] @critical_section _dbm.dbm.__exit__ *exc_info: array Close the database. [clinic start generated code]*/ static PyObject * _dbm_dbm___exit___impl(dbmobject *self, PyObject * const *exc_info, Py_ssize_t exc_info_length) /*[clinic end generated code: output=f9549bf513b3285d input=340d8190b6fb0f15]*/ { return _dbm_dbm_close_impl(self); } static PyMethodDef dbm_methods[] = { _DBM_DBM_CLOSE_METHODDEF _DBM_DBM_KEYS_METHODDEF _DBM_DBM_GET_METHODDEF _DBM_DBM_SETDEFAULT_METHODDEF _DBM_DBM_CLEAR_METHODDEF {"__enter__", dbm__enter__, METH_NOARGS, NULL}, _DBM_DBM___EXIT___METHODDEF {NULL, NULL} /* sentinel */ }; static PyType_Slot dbmtype_spec_slots[] = { {Py_tp_dealloc, dbm_dealloc}, {Py_tp_traverse, _PyObject_VisitType}, {Py_tp_methods, dbm_methods}, {Py_sq_contains, dbm_contains}, {Py_mp_length, dbm_length}, {Py_mp_subscript, dbm_subscript}, {Py_mp_ass_subscript, dbm_ass_sub}, {Py_nb_bool, dbm_bool}, {0, 0} }; static PyType_Spec dbmtype_spec = { .name = "_dbm.dbm", .basicsize = sizeof(dbmobject), // Calling PyType_GetModuleState() on a subclass is not safe. // dbmtype_spec does not have Py_TPFLAGS_BASETYPE flag // which prevents to create a subclass. // So calling PyType_GetModuleState() in this file is always safe. .flags = (Py_TPFLAGS_DEFAULT | Py_TPFLAGS_DISALLOW_INSTANTIATION | Py_TPFLAGS_HAVE_GC | Py_TPFLAGS_IMMUTABLETYPE), .slots = dbmtype_spec_slots, }; /* ----------------------------------------------------------------- */ /*[clinic input] _dbm.open as dbmopen filename: object The filename to open. flags: str="r" How to open the file. "r" for reading, "w" for writing, etc. mode: int(py_default="0o666") = 0o666 If creating a new file, the mode bits for the new file (e.g. os.O_RDWR). / Return a database object. [clinic start generated code]*/ static PyObject * dbmopen_impl(PyObject *module, PyObject *filename, const char *flags, int mode) /*[clinic end generated code: output=9527750f5df90764 input=d8cf50a9f81218c8]*/ { int iflags; _dbm_state *state = get_dbm_state(module); assert(state != NULL); if (strcmp(flags, "r") == 0) { iflags = O_RDONLY; } else if (strcmp(flags, "w") == 0) { iflags = O_RDWR; } else if (strcmp(flags, "rw") == 0) { /* Backward compatibility */ iflags = O_RDWR|O_CREAT; } else if (strcmp(flags, "c") == 0) { iflags = O_RDWR|O_CREAT; } else if (strcmp(flags, "n") == 0) { iflags = O_RDWR|O_CREAT|O_TRUNC; } else { PyErr_SetString(state->dbm_error, "arg 2 to open should be 'r', 'w', 'c', or 'n'"); return NULL; } PyObject *filenamebytes; if (!PyUnicode_FSConverter(filename, &filenamebytes)) { return NULL; } const char *name = PyBytes_AS_STRING(filenamebytes); PyObject *self = newdbmobject(state, name, iflags, mode); Py_DECREF(filenamebytes); return self; } static PyMethodDef dbmmodule_methods[] = { DBMOPEN_METHODDEF { 0, 0 }, }; #if defined(GDBM_VERSION_MAJOR) || defined(DB_VERSION_MAJOR) static PyStructSequence_Field version_info_fields[] = { {"major", "Major release number"}, {"minor", "Minor release number"}, {"patch", "Patch release number"}, {0} }; static PyObject * make_version_info(PyTypeObject *type, int major, int minor, int patch) { PyObject *version; int pos = 0; version = PyStructSequence_New(type); if (version == NULL) { return NULL; } #define SetItem(VALUE) \ PyStructSequence_SET_ITEM(version, pos++, VALUE); \ if (PyErr_Occurred()) { \ Py_DECREF(version); \ return NULL; \ } SetItem(PyLong_FromLong(major)) SetItem(PyLong_FromLong(minor)) SetItem(PyLong_FromLong(patch)) #undef SetItem return version; } #endif #if defined(GDBM_VERSION_MAJOR) PyDoc_STRVAR(gdbm_version_info__doc__, "_dbm.gdbm_version_info\n\ \n\ GDBM version information as a named tuple."); static PyStructSequence_Desc gdbm_version_info_desc = { "_dbm.gdbm_version_info", /* name */ gdbm_version_info__doc__, /* doc */ version_info_fields, /* fields */ 3 }; static int add_version_constants(PyObject *module) { if (PyModule_AddStringConstant(module, "gdbm_version", gdbm_version) < 0) { return -1; } PyTypeObject *version_type; version_type = PyStructSequence_NewType(&gdbm_version_info_desc); if (version_type == NULL) { return -1; } if (PyModule_Add(module, "GDBM_VERSION_INFO", make_version_info(version_type, GDBM_VERSION_MAJOR, GDBM_VERSION_MINOR, GDBM_VERSION_PATCH)) < 0) { Py_DECREF(version_type); return -1; } if (PyModule_Add(module, "gdbm_version_info", make_version_info(version_type, gdbm_version_number[0], gdbm_version_number[1], gdbm_version_number[2])) < 0) { Py_DECREF(version_type); return -1; } Py_DECREF(version_type); return 0; } #elif defined(DB_VERSION_MAJOR) PyDoc_STRVAR(bdb_version_info__doc__, "_dbm.bdb_version_info\n\ \n\ Berkeley DB version information as a named tuple."); static PyStructSequence_Desc bdb_version_info_desc = { "_dbm.bdb_version_info", /* name */ bdb_version_info__doc__, /* doc */ version_info_fields, /* fields */ 3 }; static int add_version_constants(PyObject *module) { int major, minor, patch; const char *version = db_version(&major, &minor, &patch); if (PyModule_AddStringConstant(module, "BDB_VERSION", DB_VERSION_STRING) < 0) { return -1; } if (PyModule_AddStringConstant(module, "bdb_version", version) < 0) { return -1; } PyTypeObject *version_type; version_type = PyStructSequence_NewType(&bdb_version_info_desc); if (version_type == NULL) { return -1; } if (PyModule_Add(module, "BDB_VERSION_INFO", make_version_info(version_type, DB_VERSION_MAJOR, DB_VERSION_MINOR, DB_VERSION_PATCH)) < 0) { Py_DECREF(version_type); return -1; } if (PyModule_Add(module, "bdb_version_info", make_version_info(version_type, major, minor, patch)) < 0) { Py_DECREF(version_type); return -1; } Py_DECREF(version_type); return 0; } #else static int add_version_constants(PyObject *module) { return 0; } #endif static int _dbm_exec(PyObject *module) { _dbm_state *state = get_dbm_state(module); state->dbm_type = (PyTypeObject *)PyType_FromModuleAndSpec(module, &dbmtype_spec, NULL); if (state->dbm_type == NULL) { return -1; } state->dbm_error = PyErr_NewException("_dbm.error", PyExc_OSError, NULL); if (state->dbm_error == NULL) { return -1; } if (PyModule_AddStringConstant(module, "library", which_dbm) < 0) { return -1; } if (add_version_constants(module) < 0) { return -1; } if (PyModule_AddType(module, (PyTypeObject *)state->dbm_error) < 0) { return -1; } return 0; } static int _dbm_module_traverse(PyObject *module, visitproc visit, void *arg) { _dbm_state *state = get_dbm_state(module); Py_VISIT(state->dbm_error); Py_VISIT(state->dbm_type); return 0; } static int _dbm_module_clear(PyObject *module) { _dbm_state *state = get_dbm_state(module); Py_CLEAR(state->dbm_error); Py_CLEAR(state->dbm_type); return 0; } static void _dbm_module_free(void *module) { (void)_dbm_module_clear((PyObject *)module); } static PyModuleDef_Slot _dbmmodule_slots[] = { _Py_ABI_SLOT, {Py_mod_exec, _dbm_exec}, {Py_mod_multiple_interpreters, Py_MOD_PER_INTERPRETER_GIL_SUPPORTED}, {Py_mod_gil, Py_MOD_GIL_NOT_USED}, {0, NULL} }; static struct PyModuleDef _dbmmodule = { PyModuleDef_HEAD_INIT, .m_name = "_dbm", .m_size = sizeof(_dbm_state), .m_methods = dbmmodule_methods, .m_slots = _dbmmodule_slots, .m_traverse = _dbm_module_traverse, .m_clear = _dbm_module_clear, .m_free = _dbm_module_free, }; PyMODINIT_FUNC PyInit__dbm(void) { return PyModuleDef_Init(&_dbmmodule); }