gdb/python/py-event.c

   1 /* Python interface to inferior events.
   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 "py-event.h"
  21
  22 void
  23 evpy_dealloc (PyObject *self)
  24 {
  25   Py_XDECREF (((event_object *) self)->dict);
  26   self->ob_type->tp_free (self);
  27 }
  28
  29 PyObject *
  30 create_event_object (PyTypeObject *py_type)
  31 {
  32   event_object *event_obj;
  33
  34   event_obj = PyObject_New (event_object, py_type);
  35   if (!event_obj)
  36     goto fail;
  37
  38   event_obj->dict = PyDict_New ();
  39   if (!event_obj->dict)
  40     goto fail;
  41
  42   return (PyObject*) event_obj;
  43
  44  fail:
  45   Py_XDECREF (event_obj);
  46   return NULL;
  47 }
  48
  49 /* Add the attribute ATTR to the event object EVENT.  In
  50    python this attribute will be accessible by the name NAME.
  51    returns 0 if the operation succeeds and -1 otherwise.  */
  52
  53 int
  54 evpy_add_attribute (PyObject *event, char *name, PyObject *attr)
  55 {
  56   return PyObject_SetAttrString (event, name, attr);
  57 }
  58
  59 /* Initialize the Python event code.  */
  60
  61 void
  62 gdbpy_initialize_event (void)
  63 {
  64   gdbpy_initialize_event_generic (&event_object_type,
  65                                   "Event");
  66 }
  67
  68 /* Initialize the given event type.  If BASE is not NULL it will
  69   be set as the types base.
  70   Returns 0 if initialization was successful -1 otherwise.  */
  71
  72 int
  73 gdbpy_initialize_event_generic (PyTypeObject *type,
  74                                 char *name)
  75 {
  76   if (PyType_Ready (type) < 0)
  77     goto fail;
  78
  79   Py_INCREF (type);
  80   if (PyModule_AddObject (gdb_module, name, (PyObject *) type) < 0)
  81     goto fail;
  82
  83   return 0;
  84
  85   fail:
  86     Py_XDECREF (type);
  87     return -1;
  88 }
  89
  90
  91 /* Notify the list of listens that the given EVENT has occurred.
  92    returns 0 if emit is successful -1 otherwise.  */
  93
  94 int
  95 evpy_emit_event (PyObject *event,
  96                  eventregistry_object *registry)
  97 {
  98   PyObject *callback_list_copy = NULL;
  99   Py_ssize_t i;
 100
 101   /* Create a copy of call back list and use that for
 102      notifying listeners to avoid skipping callbacks
 103      in the case of a callback being disconnected during
 104      a notification.  */
 105   callback_list_copy = PySequence_List (registry->callbacks);
 106   if (!callback_list_copy)
 107     goto fail;
 108
 109   for (i = 0; i < PyList_Size (callback_list_copy); i++)
 110     {
 111       PyObject *func = PyList_GetItem (callback_list_copy, i);
 112
 113       if (func == NULL)
 114         goto fail;
 115
 116       if (!PyObject_CallFunctionObjArgs (func, event, NULL))
 117         {
 118           /* Print the trace here, but keep going -- we want to try to
 119              call all of the callbacks even if one is broken.  */
 120           gdbpy_print_stack ();
 121         }
 122     }
 123
 124   Py_XDECREF (callback_list_copy);
 125   Py_XDECREF (event);
 126   return 0;
 127
 128  fail:
 129   gdbpy_print_stack ();
 130   Py_XDECREF (callback_list_copy);
 131   Py_XDECREF (event);
 132   return -1;
 133 }
 134
 135 PyTypeObject event_object_type =
 136 {
 137   PyObject_HEAD_INIT (NULL)
 138   0,                                          /* ob_size */
 139   "gdb.Event",                                /* tp_name */
 140   sizeof (event_object),                      /* tp_basicsize */
 141   0,                                          /* tp_itemsize */
 142   evpy_dealloc,                               /* tp_dealloc */
 143   0,                                          /* tp_print */
 144   0,                                          /* tp_getattr */
 145   0,                                          /* tp_setattr */
 146   0,                                          /* tp_compare */
 147   0,                                          /* tp_repr */
 148   0,                                          /* tp_as_number */
 149   0,                                          /* tp_as_sequence */
 150   0,                                          /* tp_as_mapping */
 151   0,                                          /* tp_hash  */
 152   0,                                          /* tp_call */
 153   0,                                          /* tp_str */
 154   0,                                          /* tp_getattro */
 155   0,                                          /* tp_setattro */
 156   0,                                          /* tp_as_buffer */
 157   Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,   /* tp_flags */
 158   "GDB event object",                         /* tp_doc */
 159   0,                                          /* tp_traverse */
 160   0,                                          /* tp_clear */
 161   0,                                          /* tp_richcompare */
 162   0,                                          /* tp_weaklistoffset */
 163   0,                                          /* tp_iter */
 164   0,                                          /* tp_iternext */
 165   0,                                          /* tp_methods */
 166   0,                                          /* tp_members */
 167   0,                                          /* tp_getset */
 168   0,                                          /* tp_base */
 169   0,                                          /* tp_dict */
 170   0,                                          /* tp_descr_get */
 171   0,                                          /* tp_descr_set */
 172   offsetof (event_object, dict),              /* tp_dictoffset */
 173   0,                                          /* tp_init */
 174   0                                           /* tp_alloc */
 175 };