_dbus_bindings/signature.c

   1 /* Implementation of Signature type for D-Bus bindings.
   2  *
   3  * Copyright (C) 2006 Collabora Ltd.
   4  *
   5  * Licensed under the Academic Free License version 2.1
   6  *
   7  * This library is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU Lesser General Public License as published by
   9  * the Free Software Foundation; either version 2.1 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public License
  18  * along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  */
  22
  23 #include <Python.h>
  24 #include <structmember.h>
  25
  26 #include <stdint.h>
  27
  28 #include "dbus_bindings-internal.h"
  29 #include "types-internal.h"
  30
  31 PyDoc_STRVAR(Signature_tp_doc,
  32 "A string subclass whose values are restricted to valid D-Bus\n"
  33 "signatures. When iterated over, instead of individual characters it\n"
  34 "produces Signature instances representing single complete types.\n"
  35 "\n"
  36 "Constructor::\n"
  37 "\n"
  38 "    ``Signature(value: str or unicode[, variant_level: int]) -> Signature``\n"
  39 "\n"
  40 "``value`` must be a valid D-Bus signature (zero or more single complete\n"
  41 "types).\n"
  42 "\n"
  43 "``variant_level`` must be non-negative; the default is 0.\n"
  44 "\n"
  45 ":IVariables:\n"
  46 "  `variant_level` : int\n"
  47 "    Indicates how many nested Variant containers this object\n"
  48 "    is contained in: if a message's wire format has a variant containing a\n"
  49 "    variant containing a signature, this is represented in Python by a\n"
  50 "    Signature with variant_level==2.\n"
  51 );
  52
  53 typedef struct {
  54     PyObject_HEAD
  55     PyObject *string;
  56     DBusSignatureIter iter;
  57 } SignatureIter;
  58
  59 static void
  60 SignatureIter_tp_dealloc (SignatureIter *self)
  61 {
  62     Py_XDECREF(self->string);
  63     self->string = NULL;
  64     PyObject_Del(self);
  65 }
  66
  67 static PyObject *
  68 SignatureIter_tp_iternext (SignatureIter *self)
  69 {
  70     char *sig;
  71     PyObject *obj;
  72
  73     /* Stop immediately if finished or not correctly initialized */
  74     if (!self->string) return NULL;
  75
  76     sig = dbus_signature_iter_get_signature(&(self->iter));
  77     if (!sig) return PyErr_NoMemory();
  78     obj = PyObject_CallFunction((PyObject *)&DBusPySignature_Type, "s", sig);
  79     dbus_free(sig);
  80     if (!obj) return NULL;
  81
  82     if (!dbus_signature_iter_next(&(self->iter))) {
  83         /* mark object as having been finished with */
  84         Py_DECREF(self->string);
  85         self->string = NULL;
  86     }
  87
  88     return obj;
  89 }
  90
  91 static PyObject *
  92 SignatureIter_tp_iter(PyObject *self)
  93 {
  94     Py_INCREF(self);
  95     return self;
  96 }
  97
  98 static PyTypeObject SignatureIterType = {
  99     PyObject_HEAD_INIT(DEFERRED_ADDRESS(&PyType_Type))
 100     0,
 101     "_dbus_bindings._SignatureIter",
 102     sizeof(SignatureIter),
 103     0,
 104     (destructor)SignatureIter_tp_dealloc,   /* tp_dealloc */
 105     0,                                      /* tp_print */
 106     0,                                      /* tp_getattr */
 107     0,                                      /* tp_setattr */
 108     0,                                      /* tp_compare */
 109     0,                                      /* tp_repr */
 110     0,                                      /* tp_as_number */
 111     0,                                      /* tp_as_sequence */
 112     0,                                      /* tp_as_mapping */
 113     0,                                      /* tp_hash */
 114     0,                                      /* tp_call */
 115     0,                                      /* tp_str */
 116     0,                                      /* tp_getattro */
 117     0,                                      /* tp_setattro */
 118     0,                                      /* tp_as_buffer */
 119     Py_TPFLAGS_DEFAULT,                     /* tp_flags */
 120     0,                                      /* tp_doc */
 121     0,                                      /* tp_traverse */
 122     0,                                      /* tp_clear */
 123     0,                                      /* tp_richcompare */
 124     0,                                      /* tp_weaklistoffset */
 125     SignatureIter_tp_iter,                  /* tp_iter */
 126     (iternextfunc)SignatureIter_tp_iternext,  /* tp_iternext */
 127     0,                                      /* tp_methods */
 128     0,                                      /* tp_members */
 129     0,                                      /* tp_getset */
 130     0,                                      /* tp_base */
 131     0,                                      /* tp_dict */
 132     0,                                      /* tp_descr_get */
 133     0,                                      /* tp_descr_set */
 134     0,                                      /* tp_dictoffset */
 135     0,                                      /* tp_init */
 136     0,                                      /* tp_alloc */
 137     /* deliberately not callable! Use iter(Signature) instead */
 138     0,                                      /* tp_new */
 139     0,                                      /* tp_free */
 140 };
 141
 142 static PyObject *
 143 Signature_tp_iter (PyObject *self)
 144 {
 145     SignatureIter *iter = PyObject_New(SignatureIter, &SignatureIterType);
 146     if (!iter) return NULL;
 147
 148     if (PyString_AS_STRING (self)[0]) {
 149         Py_INCREF(self);
 150         iter->string = self;
 151         dbus_signature_iter_init(&(iter->iter), PyString_AS_STRING(self));
 152     }
 153     else {
 154         /* this is a null string, make a null iterator */
 155         iter->string = NULL;
 156     }
 157     return (PyObject *)iter;
 158 }
 159
 160 static PyObject *
 161 Signature_tp_new (PyTypeObject *cls, PyObject *args, PyObject *kwargs)
 162 {
 163     const char *str = NULL;
 164     PyObject *ignored;
 165     static char *argnames[] = {"object_path", "variant_level", NULL};
 166
 167     if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s|O:__new__", argnames,
 168                                      &str, &ignored)) return NULL;
 169     if (!dbus_signature_validate(str, NULL)) {
 170         PyErr_SetString(PyExc_ValueError, "Corrupt type signature");
 171         return NULL;
 172     }
 173     return (DBusPyStrBase_Type.tp_new)(cls, args, kwargs);
 174 }
 175
 176 PyTypeObject DBusPySignature_Type = {
 177     PyObject_HEAD_INIT(DEFERRED_ADDRESS(&PyType_Type))
 178     0,
 179     "dbus.Signature",
 180     0,
 181     0,
 182     0,                                      /* tp_dealloc */
 183     0,                                      /* tp_print */
 184     0,                                      /* tp_getattr */
 185     0,                                      /* tp_setattr */
 186     0,                                      /* tp_compare */
 187     0,                                      /* tp_repr */
 188     0,                                      /* tp_as_number */
 189     0,                                      /* tp_as_sequence */
 190     0,                                      /* tp_as_mapping */
 191     0,                                      /* tp_hash */
 192     0,                                      /* tp_call */
 193     0,                                      /* tp_str */
 194     0,                                      /* tp_getattro */
 195     0,                                      /* tp_setattro */
 196     0,                                      /* tp_as_buffer */
 197     Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */
 198     Signature_tp_doc,                       /* tp_doc */
 199     0,                                      /* tp_traverse */
 200     0,                                      /* tp_clear */
 201     0,                                      /* tp_richcompare */
 202     0,                                      /* tp_weaklistoffset */
 203     Signature_tp_iter,                      /* tp_iter */
 204     0,                                      /* tp_iternext */
 205     0,                                      /* tp_methods */
 206     0,                                      /* tp_members */
 207     0,                                      /* tp_getset */
 208     DEFERRED_ADDRESS(&DBusPythonStringType), /* tp_base */
 209     0,                                      /* tp_dict */
 210     0,                                      /* tp_descr_get */
 211     0,                                      /* tp_descr_set */
 212     0,                                      /* tp_dictoffset */
 213     0,                                      /* tp_init */
 214     0,                                      /* tp_alloc */
 215     Signature_tp_new,                       /* tp_new */
 216     0,                                      /* tp_free */
 217 };
 218
 219 dbus_bool_t
 220 dbus_py_init_signature(void)
 221 {
 222     if (PyType_Ready(&SignatureIterType) < 0) return 0;
 223
 224     DBusPySignature_Type.tp_base = &DBusPyStrBase_Type;
 225     if (PyType_Ready(&DBusPySignature_Type) < 0) return 0;
 226     DBusPySignature_Type.tp_print = NULL;
 227
 228     return 1;
 229 }
 230
 231 dbus_bool_t
 232 dbus_py_insert_signature(PyObject *this_module)
 233 {
 234     Py_INCREF(&DBusPySignature_Type);
 235     if (PyModule_AddObject(this_module, "Signature",
 236                            (PyObject *)&DBusPySignature_Type) < 0) return 0;
 237     Py_INCREF(&SignatureIterType);
 238     if (PyModule_AddObject(this_module, "_SignatureIter",
 239                            (PyObject *)&SignatureIterType) < 0) return 0;
 240
 241     return 1;
 242 }
 243
 244 /* vim:set ft=c cino< sw=4 sts=4 et: */