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