contrib/gdb-7/gdb/python/py-evtregistry.c

   1 /* Python interface to inferior thread event registries.
   2
   3    Copyright (C) 2009, 2010, 2011 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   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    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program 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 General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "command.h"
  22 #include "py-events.h"
  23
  24 static PyTypeObject eventregistry_object_type;
  25
  26 /* Implementation of EventRegistry.connect () -> NULL.
  27    Add FUNCTION to the list of listeners.  */
  28
  29 static PyObject *
  30 evregpy_connect (PyObject *self, PyObject *function)
  31 {
  32   PyObject *func;
  33   PyObject *callback_list = (((eventregistry_object *) self)->callbacks);
  34
  35   if (!PyArg_ParseTuple (function, "O", &func))
  36     return NULL;
  37
  38   if (!PyCallable_Check (func))
  39     {
  40       PyErr_SetString (PyExc_RuntimeError, "Function is not callable");
  41       return NULL;
  42     }
  43
  44   if (PyList_Append (callback_list, func) < 0)
  45     return NULL;
  46
  47   Py_RETURN_NONE;
  48 }
  49
  50 /* Implementation of EventRegistry.disconnect () -> NULL.
  51    Remove FUNCTION from the list of listeners.  */
  52
  53 static PyObject *
  54 evregpy_disconnect (PyObject *self, PyObject *function)
  55 {
  56   PyObject *func;
  57   int index;
  58   PyObject *callback_list = (((eventregistry_object *) self)->callbacks);
  59
  60   if (!PyArg_ParseTuple (function, "O", &func))
  61     return NULL;
  62
  63   index = PySequence_Index (callback_list, func);
  64   if (index < 0)
  65     Py_RETURN_NONE;
  66
  67   if (PySequence_DelItem (callback_list, index) < 0)
  68     return NULL;
  69
  70   Py_RETURN_NONE;
  71 }
  72
  73 /* Create a new event registry.  This function uses PyObject_New
  74    and therefore returns a new reference that callers must handle.  */
  75
  76 eventregistry_object *
  77 create_eventregistry_object (void)
  78 {
  79   eventregistry_object *eventregistry_obj;
  80
  81   eventregistry_obj = PyObject_New (eventregistry_object,
  82                                     &eventregistry_object_type);
  83
  84   if (!eventregistry_obj)
  85     return NULL;
  86
  87   eventregistry_obj->callbacks = PyList_New (0);
  88   if (!eventregistry_obj->callbacks)
  89     return NULL;
  90
  91   return eventregistry_obj;
  92 }
  93
  94 static void
  95 evregpy_dealloc (PyObject *self)
  96 {
  97   Py_XDECREF (((eventregistry_object *) self)->callbacks);
  98   self->ob_type->tp_free (self);
  99 }
 100
 101 /* Initialize the Python event registry code.  */
 102
 103 void
 104 gdbpy_initialize_eventregistry (void)
 105 {
 106   if (PyType_Ready (&eventregistry_object_type) < 0)
 107     return;
 108
 109   Py_INCREF (&eventregistry_object_type);
 110   PyModule_AddObject (gdb_module, "EventRegistry",
 111                       (PyObject *) &eventregistry_object_type);
 112 }
 113
 114 /* Retern the number of listeners currently connected to this
 115    registry.  */
 116
 117 int
 118 evregpy_no_listeners_p (eventregistry_object *registry)
 119 {
 120   return PyList_Size (registry->callbacks) == 0;
 121 }
 122
 123 static PyMethodDef eventregistry_object_methods[] =
 124 {
 125   { "connect", evregpy_connect, METH_VARARGS, "Add function" },
 126   { "disconnect", evregpy_disconnect, METH_VARARGS, "Remove function" },
 127   { NULL } /* Sentinel.  */
 128 };
 129
 130 static PyTypeObject eventregistry_object_type =
 131 {
 132   PyObject_HEAD_INIT (NULL)
 133   0,                                          /* ob_size */
 134   "gdb.EventRegistry",                        /* tp_name */
 135   sizeof (eventregistry_object),              /* tp_basicsize */
 136   0,                                          /* tp_itemsize */
 137   evregpy_dealloc,                            /* tp_dealloc */
 138   0,                                          /* tp_print */
 139   0,                                          /* tp_getattr */
 140   0,                                          /* tp_setattr */
 141   0,                                          /* tp_compare */
 142   0,                                          /* tp_repr */
 143   0,                                          /* tp_as_number */
 144   0,                                          /* tp_as_sequence */
 145   0,                                          /* tp_as_mapping */
 146   0,                                          /* tp_hash  */
 147   0,                                          /* tp_call */
 148   0,                                          /* tp_str */
 149   0,                                          /* tp_getattro */
 150   0,                                          /* tp_setattro */
 151   0,                                          /* tp_as_buffer */
 152   Py_TPFLAGS_DEFAULT,                         /* tp_flags */
 153   "GDB event registry object",                /* tp_doc */
 154   0,                                          /* tp_traverse */
 155   0,                                          /* tp_clear */
 156   0,                                          /* tp_richcompare */
 157   0,                                          /* tp_weaklistoffset */
 158   0,                                          /* tp_iter */
 159   0,                                          /* tp_iternext */
 160   eventregistry_object_methods,               /* tp_methods */
 161   0,                                          /* tp_members */
 162   0,                                          /* tp_getset */
 163   0,                                          /* tp_base */
 164   0,                                          /* tp_dict */
 165   0,                                          /* tp_descr_get */
 166   0,                                          /* tp_descr_set */
 167   0,                                          /* tp_dictoffset */
 168   0,                                          /* tp_init */
 169   0                                           /* tp_alloc */
 170 };