gobject/gsourceclosure.c

   1 /* GObject - GLib Type, Object, Parameter and Signal Library
   2  * Copyright (C) 2001 Red Hat, Inc.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General
  15  * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "config.h"
  19
  20 #include "gsourceclosure.h"
  21 #include "gboxed.h"
  22 #include "genums.h"
  23 #include "gmarshal.h"
  24 #include "gvalue.h"
  25 #include "gvaluetypes.h"
  26 #ifdef G_OS_UNIX
  27 #include "glib-unix.h"
  28 #endif
  29
  30 G_DEFINE_BOXED_TYPE (GIOChannel, g_io_channel, g_io_channel_ref, g_io_channel_unref)
  31
  32 GType
  33 g_io_condition_get_type (void)
  34 {
  35   static volatile GType etype = 0;
  36
  37   if (g_once_init_enter (&etype))
  38     {
  39       static const GFlagsValue values[] = {
  40         { G_IO_IN,   "G_IO_IN",   "in" },
  41         { G_IO_OUT,  "G_IO_OUT",  "out" },
  42         { G_IO_PRI,  "G_IO_PRI",  "pri" },
  43         { G_IO_ERR,  "G_IO_ERR",  "err" },
  44         { G_IO_HUP,  "G_IO_HUP",  "hup" },
  45         { G_IO_NVAL, "G_IO_NVAL", "nval" },
  46         { 0, NULL, NULL }
  47       };
  48       GType type_id = g_flags_register_static ("GIOCondition", values);
  49       g_once_init_leave (&etype, type_id);
  50     }
  51   return etype;
  52 }
  53
  54 /* We need to hand-write this marshaler, since it doesn't have an
  55  * instance object.
  56  */
  57 static void
  58 source_closure_marshal_BOOLEAN__VOID (GClosure     *closure,
  59                                       GValue       *return_value,
  60                                       guint         n_param_values,
  61                                       const GValue *param_values,
  62                                       gpointer      invocation_hint,
  63                                       gpointer      marshal_data)
  64 {
  65   GSourceFunc callback;
  66   GCClosure *cc = (GCClosure*) closure;
  67   gboolean v_return;
  68
  69   g_return_if_fail (return_value != NULL);
  70   g_return_if_fail (n_param_values == 0);
  71
  72   callback = (GSourceFunc) (marshal_data ? marshal_data : cc->callback);
  73
  74   v_return = callback (closure->data);
  75
  76   g_value_set_boolean (return_value, v_return);
  77 }
  78
  79 static gboolean
  80 io_watch_closure_callback (GIOChannel   *channel,
  81                            GIOCondition  condition,
  82                            gpointer      data)
  83 {
  84   GClosure *closure = data;
  85
  86   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
  87   GValue result_value = G_VALUE_INIT;
  88   gboolean result;
  89
  90   g_value_init (&result_value, G_TYPE_BOOLEAN);
  91   g_value_init (&params[0], G_TYPE_IO_CHANNEL);
  92   g_value_set_boxed (&params[0], channel);
  93
  94   g_value_init (&params[1], G_TYPE_IO_CONDITION);
  95   g_value_set_flags (&params[1], condition);
  96
  97   g_closure_invoke (closure, &result_value, 2, params, NULL);
  98
  99   result = g_value_get_boolean (&result_value);
 100   g_value_unset (&result_value);
 101   g_value_unset (&params[0]);
 102   g_value_unset (&params[1]);
 103
 104   return result;
 105 }
 106
 107 static gboolean
 108 g_child_watch_closure_callback (GPid     pid,
 109                                 gint     status,
 110                                 gpointer data)
 111 {
 112   GClosure *closure = data;
 113
 114   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 115   GValue result_value = G_VALUE_INIT;
 116   gboolean result;
 117
 118   g_value_init (&result_value, G_TYPE_BOOLEAN);
 119
 120 #ifdef G_OS_UNIX
 121   g_value_init (&params[0], G_TYPE_ULONG);
 122   g_value_set_ulong (&params[0], pid);
 123 #endif
 124 #ifdef G_OS_WIN32
 125   g_value_init (&params[0], G_TYPE_POINTER);
 126   g_value_set_pointer (&params[0], pid);
 127 #endif
 128
 129   g_value_init (&params[1], G_TYPE_INT);
 130   g_value_set_int (&params[1], status);
 131
 132   g_closure_invoke (closure, &result_value, 2, params, NULL);
 133
 134   result = g_value_get_boolean (&result_value);
 135   g_value_unset (&result_value);
 136   g_value_unset (&params[0]);
 137   g_value_unset (&params[1]);
 138
 139   return result;
 140 }
 141
 142 #ifdef G_OS_UNIX
 143 static gboolean
 144 g_unix_fd_source_closure_callback (int           fd,
 145                                    GIOCondition  condition,
 146                                    gpointer      data)
 147 {
 148   GClosure *closure = data;
 149
 150   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 151   GValue result_value = G_VALUE_INIT;
 152   gboolean result;
 153
 154   g_value_init (&result_value, G_TYPE_BOOLEAN);
 155
 156   g_value_init (&params[0], G_TYPE_INT);
 157   g_value_set_int (&params[0], fd);
 158
 159   g_value_init (&params[1], G_TYPE_IO_CONDITION);
 160   g_value_set_flags (&params[1], condition);
 161
 162   g_closure_invoke (closure, &result_value, 2, params, NULL);
 163
 164   result = g_value_get_boolean (&result_value);
 165   g_value_unset (&result_value);
 166   g_value_unset (&params[0]);
 167   g_value_unset (&params[1]);
 168
 169   return result;
 170 }
 171 #endif
 172
 173 static gboolean
 174 source_closure_callback (gpointer data)
 175 {
 176   GClosure *closure = data;
 177   GValue result_value = G_VALUE_INIT;
 178   gboolean result;
 179
 180   g_value_init (&result_value, G_TYPE_BOOLEAN);
 181
 182   g_closure_invoke (closure, &result_value, 0, NULL, NULL);
 183
 184   result = g_value_get_boolean (&result_value);
 185   g_value_unset (&result_value);
 186
 187   return result;
 188 }
 189
 190 static void
 191 closure_callback_get (gpointer     cb_data,
 192                       GSource     *source,
 193                       GSourceFunc *func,
 194                       gpointer    *data)
 195 {
 196   GSourceFunc closure_callback = source->source_funcs->closure_callback;
 197
 198   if (!closure_callback)
 199     {
 200       if (source->source_funcs == &g_io_watch_funcs)
 201         closure_callback = (GSourceFunc)io_watch_closure_callback;
 202       else if (source->source_funcs == &g_child_watch_funcs)
 203         closure_callback = (GSourceFunc)g_child_watch_closure_callback;
 204 #ifdef G_OS_UNIX
 205       else if (source->source_funcs == &g_unix_fd_source_funcs)
 206         closure_callback = (GSourceFunc)g_unix_fd_source_closure_callback;
 207 #endif
 208       else if (source->source_funcs == &g_timeout_funcs ||
 209 #ifdef G_OS_UNIX
 210                source->source_funcs == &g_unix_signal_funcs ||
 211 #endif
 212                source->source_funcs == &g_idle_funcs)
 213         closure_callback = source_closure_callback;
 214     }
 215
 216   *func = closure_callback;
 217   *data = cb_data;
 218 }
 219
 220 static GSourceCallbackFuncs closure_callback_funcs = {
 221   (void (*) (gpointer)) g_closure_ref,
 222   (void (*) (gpointer)) g_closure_unref,
 223   closure_callback_get
 224 };
 225
 226 static void
 227 closure_invalidated (gpointer  user_data,
 228                      GClosure *closure)
 229 {
 230   g_source_destroy (user_data);
 231 }
 232
 233 /**
 234  * g_source_set_closure:
 235  * @source: the source
 236  * @closure: a #GClosure
 237  *
 238  * Set the callback for a source as a #GClosure.
 239  *
 240  * If the source is not one of the standard GLib types, the @closure_callback
 241  * and @closure_marshal fields of the #GSourceFuncs structure must have been
 242  * filled in with pointers to appropriate functions.
 243  */
 244 void
 245 g_source_set_closure (GSource  *source,
 246                       GClosure *closure)
 247 {
 248   g_return_if_fail (source != NULL);
 249   g_return_if_fail (closure != NULL);
 250
 251   if (!source->source_funcs->closure_callback &&
 252 #ifdef G_OS_UNIX
 253       source->source_funcs != &g_unix_fd_source_funcs &&
 254       source->source_funcs != &g_unix_signal_funcs &&
 255 #endif
 256       source->source_funcs != &g_child_watch_funcs &&
 257       source->source_funcs != &g_io_watch_funcs &&
 258       source->source_funcs != &g_timeout_funcs &&
 259       source->source_funcs != &g_idle_funcs)
 260     {
 261       g_critical (G_STRLOC ": closure cannot be set on GSource without GSourceFuncs::closure_callback");
 262       return;
 263     }
 264
 265   g_closure_ref (closure);
 266   g_closure_sink (closure);
 267   g_source_set_callback_indirect (source, closure, &closure_callback_funcs);
 268
 269   g_closure_add_invalidate_notifier (closure, source, closure_invalidated);
 270
 271   if (G_CLOSURE_NEEDS_MARSHAL (closure))
 272     {
 273       GClosureMarshal marshal = (GClosureMarshal)source->source_funcs->closure_marshal;
 274       if (marshal)
 275         g_closure_set_marshal (closure, marshal);
 276       else if (source->source_funcs == &g_idle_funcs ||
 277 #ifdef G_OS_UNIX
 278                source->source_funcs == &g_unix_signal_funcs ||
 279 #endif
 280                source->source_funcs == &g_timeout_funcs)
 281         g_closure_set_marshal (closure, source_closure_marshal_BOOLEAN__VOID);
 282       else
 283         g_closure_set_marshal (closure, g_cclosure_marshal_generic);
 284     }
 285 }
 286
 287 static void
 288 dummy_closure_marshal (GClosure     *closure,
 289                        GValue       *return_value,
 290                        guint         n_param_values,
 291                        const GValue *param_values,
 292                        gpointer      invocation_hint,
 293                        gpointer      marshal_data)
 294 {
 295   if (G_VALUE_HOLDS_BOOLEAN (return_value))
 296     g_value_set_boolean (return_value, TRUE);
 297 }
 298
 299 /**
 300  * g_source_set_dummy_callback:
 301  * @source: the source
 302  *
 303  * Sets a dummy callback for @source. The callback will do nothing, and
 304  * if the source expects a #gboolean return value, it will return %TRUE.
 305  * (If the source expects any other type of return value, it will return
 306  * a 0/%NULL value; whatever g_value_init() initializes a #GValue to for
 307  * that type.)
 308  *
 309  * If the source is not one of the standard GLib types, the
 310  * @closure_callback and @closure_marshal fields of the #GSourceFuncs
 311  * structure must have been filled in with pointers to appropriate
 312  * functions.
 313  */
 314 void
 315 g_source_set_dummy_callback (GSource *source)
 316 {
 317   GClosure *closure;
 318
 319   closure = g_closure_new_simple (sizeof (GClosure), NULL);
 320   g_closure_set_meta_marshal (closure, NULL, dummy_closure_marshal);
 321   g_source_set_closure (source, closure);
 322 }