_dbus_bindings/signature.c

   1 /* Implementation of Signature type for D-Bus bindings.
   2  *
   3  * Copyright (C) 2006 Collabora Ltd. <http://www.collabora.co.uk/>
   4  *
   5  * Permission is hereby granted, free of charge, to any person
   6  * obtaining a copy of this software and associated documentation
   7  * files (the "Software"), to deal in the Software without
   8  * restriction, including without limitation the rights to use, copy,
   9  * modify, merge, publish, distribute, sublicense, and/or sell copies
  10  * of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be
  14  * included in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  19  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  20  * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  21  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  23  * DEALINGS IN THE SOFTWARE.
  24  */
  25
  26 #include <Python.h>
  27 #include <structmember.h>
  28
  29 #include <stdint.h>
  30
  31 #include "dbus_bindings-internal.h"
  32 #include "types-internal.h"
  33
  34 PyDoc_STRVAR(Signature_tp_doc,
  35 "A string subclass whose values are restricted to valid D-Bus\n"
  36 "signatures. When iterated over, instead of individual characters it\n"
  37 "produces Signature instances representing single complete types.\n"
  38 "\n"
  39 "Constructor::\n"
  40 "\n"
  41 "    ``Signature(value: str or unicode[, variant_level: int]) -> Signature``\n"
  42 "\n"
  43 "``value`` must be a valid D-Bus signature (zero or more single complete\n"
  44 "types).\n"
  45 "\n"
  46 "``variant_level`` must be non-negative; the default is 0.\n"
  47 "\n"
  48 ":IVariables:\n"
  49 "  `variant_level` : int\n"
  50 "    Indicates how many nested Variant containers this object\n"
  51 "    is contained in: if a message's wire format has a variant containing a\n"
  52 "    variant containing a signature, this is represented in Python by a\n"
  53 "    Signature with variant_level==2.\n"
  54 );
  55
  56 typedef struct {
  57     PyObject_HEAD
  58     PyObject *string;
  59     DBusSignatureIter iter;
  60 } SignatureIter;
  61
  62 static void
  63 SignatureIter_tp_dealloc (SignatureIter *self)
  64 {
  65     Py_XDECREF(self->string);
  66     self->string = NULL;
  67     PyObject_Del(self);
  68 }
  69
  70 static PyObject *
  71 SignatureIter_tp_iternext (SignatureIter *self)
  72 {
  73     char *sig;
  74     PyObject *obj;
  75
  76     /* Stop immediately if finished or not correctly initialized */
  77     if (!self->string) return NULL;
  78
  79     sig = dbus_signature_iter_get_signature(&(self->iter));
  80     if (!sig) return PyErr_NoMemory();
  81     obj = PyObject_CallFunction((PyObject *)&DBusPySignature_Type, "s", sig);
  82     dbus_free(sig);
  83     if (!obj) return NULL;
  84
  85     if (!dbus_signature_iter_next(&(self->iter))) {
  86         /* mark object as having been finished with */
  87         Py_DECREF(self->string);
  88         self->string = NULL;
  89     }
  90
  91     return obj;
  92 }
  93
  94 static PyObject *
  95 SignatureIter_tp_iter(PyObject *self)
  96 {
  97     Py_INCREF(self);
  98     return self;
  99 }
 100
 101 static PyTypeObject SignatureIterType = {
 102     PyObject_HEAD_INIT(DEFERRED_ADDRESS(&PyType_Type))
 103     0,
 104     "_dbus_bindings._SignatureIter",
 105     sizeof(SignatureIter),
 106     0,
 107     (destructor)SignatureIter_tp_dealloc,   /* tp_dealloc */
 108     0,                                      /* tp_print */
 109     0,                                      /* tp_getattr */
 110     0,                                      /* tp_setattr */
 111     0,                                      /* tp_compare */
 112     0,                                      /* tp_repr */
 113     0,                                      /* tp_as_number */
 114     0,                                      /* tp_as_sequence */
 115     0,                                      /* tp_as_mapping */
 116     0,                                      /* tp_hash */
 117     0,                                      /* tp_call */
 118     0,                                      /* tp_str */
 119     0,                                      /* tp_getattro */
 120     0,                                      /* tp_setattro */
 121     0,                                      /* tp_as_buffer */
 122     Py_TPFLAGS_DEFAULT,                     /* tp_flags */
 123     0,                                      /* tp_doc */
 124     0,                                      /* tp_traverse */
 125     0,                                      /* tp_clear */
 126     0,                                      /* tp_richcompare */
 127     0,                                      /* tp_weaklistoffset */
 128     SignatureIter_tp_iter,                  /* tp_iter */
 129     (iternextfunc)SignatureIter_tp_iternext,  /* tp_iternext */
 130     0,                                      /* tp_methods */
 131     0,                                      /* tp_members */
 132     0,                                      /* tp_getset */
 133     0,                                      /* tp_base */
 134     0,                                      /* tp_dict */
 135     0,                                      /* tp_descr_get */
 136     0,                                      /* tp_descr_set */
 137     0,                                      /* tp_dictoffset */
 138     0,                                      /* tp_init */
 139     0,                                      /* tp_alloc */
 140     /* deliberately not callable! Use iter(Signature) instead */
 141     0,                                      /* tp_new */
 142     0,                                      /* tp_free */
 143 };
 144
 145 static PyObject *
 146 Signature_tp_iter (PyObject *self)
 147 {
 148     SignatureIter *iter = PyObject_New(SignatureIter, &SignatureIterType);
 149     if (!iter) return NULL;
 150
 151     if (PyString_AS_STRING (self)[0]) {
 152         Py_INCREF(self);
 153         iter->string = self;
 154         dbus_signature_iter_init(&(iter->iter), PyString_AS_STRING(self));
 155     }
 156     else {
 157         /* this is a null string, make a null iterator */
 158         iter->string = NULL;
 159     }
 160     return (PyObject *)iter;
 161 }
 162
 163 static PyObject *
 164 Signature_tp_new (PyTypeObject *cls, PyObject *args, PyObject *kwargs)
 165 {
 166     const char *str = NULL;
 167     PyObject *ignored;
 168     static char *argnames[] = {"object_path", "variant_level", NULL};
 169
 170     if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s|O:__new__", argnames,
 171                                      &str, &ignored)) return NULL;
 172     if (!dbus_signature_validate(str, NULL)) {
 173         PyErr_SetString(PyExc_ValueError, "Corrupt type signature");
 174         return NULL;
 175     }
 176     return (DBusPyStrBase_Type.tp_new)(cls, args, kwargs);
 177 }
 178
 179 PyTypeObject DBusPySignature_Type = {
 180     PyObject_HEAD_INIT(DEFERRED_ADDRESS(&PyType_Type))
 181     0,
 182     "dbus.Signature",
 183     0,
 184     0,
 185     0,                                      /* tp_dealloc */
 186     0,                                      /* tp_print */
 187     0,                                      /* tp_getattr */
 188     0,                                      /* tp_setattr */
 189     0,                                      /* tp_compare */
 190     0,                                      /* tp_repr */
 191     0,                                      /* tp_as_number */
 192     0,                                      /* tp_as_sequence */
 193     0,                                      /* tp_as_mapping */
 194     0,                                      /* tp_hash */
 195     0,                                      /* tp_call */
 196     0,                                      /* tp_str */
 197     0,                                      /* tp_getattro */
 198     0,                                      /* tp_setattro */
 199     0,                                      /* tp_as_buffer */
 200     Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */
 201     Signature_tp_doc,                       /* tp_doc */
 202     0,                                      /* tp_traverse */
 203     0,                                      /* tp_clear */
 204     0,                                      /* tp_richcompare */
 205     0,                                      /* tp_weaklistoffset */
 206     Signature_tp_iter,                      /* tp_iter */
 207     0,                                      /* tp_iternext */
 208     0,                                      /* tp_methods */
 209     0,                                      /* tp_members */
 210     0,                                      /* tp_getset */
 211     DEFERRED_ADDRESS(&DBusPythonStringType), /* tp_base */
 212     0,                                      /* tp_dict */
 213     0,                                      /* tp_descr_get */
 214     0,                                      /* tp_descr_set */
 215     0,                                      /* tp_dictoffset */
 216     0,                                      /* tp_init */
 217     0,                                      /* tp_alloc */
 218     Signature_tp_new,                       /* tp_new */
 219     0,                                      /* tp_free */
 220 };
 221
 222 dbus_bool_t
 223 dbus_py_init_signature(void)
 224 {
 225     if (PyType_Ready(&SignatureIterType) < 0) return 0;
 226
 227     DBusPySignature_Type.tp_base = &DBusPyStrBase_Type;
 228     if (PyType_Ready(&DBusPySignature_Type) < 0) return 0;
 229     DBusPySignature_Type.tp_print = NULL;
 230
 231     return 1;
 232 }
 233
 234 dbus_bool_t
 235 dbus_py_insert_signature(PyObject *this_module)
 236 {
 237     Py_INCREF(&DBusPySignature_Type);
 238     if (PyModule_AddObject(this_module, "Signature",
 239                            (PyObject *)&DBusPySignature_Type) < 0) return 0;
 240     Py_INCREF(&SignatureIterType);
 241     if (PyModule_AddObject(this_module, "_SignatureIter",
 242                            (PyObject *)&SignatureIterType) < 0) return 0;
 243
 244     return 1;
 245 }
 246
 247 /* vim:set ft=c cino< sw=4 sts=4 et: */