gobject/gobject.c

   1 /* GObject - GLib Type, Object, Parameter and Signal Library
   2  * Copyright (C) 1998, 1999, 2000 Tim Janik and 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 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, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include <string.h>
  21
  22 #include "gobject.h"
  23 #include "gvaluecollector.h"
  24
  25
  26 #define DEBUG_OBJECTS
  27
  28
  29 /* --- macros --- */
  30 #define PARAM_SPEC_PARAM_ID(pspec)      (GPOINTER_TO_UINT (g_param_spec_get_qdata ((pspec), quark_param_id)))
  31
  32
  33 /* --- prototypes --- */
  34 static void     g_object_base_class_init                (GObjectClass   *class);
  35 static void     g_object_base_class_finalize            (GObjectClass   *class);
  36 static void     g_object_do_class_init                  (GObjectClass   *class);
  37 static void     g_object_do_init                        (GObject        *object);
  38 static void     g_object_do_queue_param_changed         (GObject        *object,
  39                                                          GParamSpec     *pspec);
  40 static void     g_object_do_dispatch_param_changed      (GObject        *object,
  41                                                          GParamSpec     *pspec);
  42 static void     g_object_last_unref                     (GObject        *object);
  43 static void     g_object_do_shutdown                    (GObject        *object);
  44 static void     g_object_do_finalize                    (GObject        *object);
  45 static void     g_value_object_init                     (GValue         *value);
  46 static void     g_value_object_free_value               (GValue         *value);
  47 static void     g_value_object_copy_value               (const GValue   *src_value,
  48                                                          GValue         *dest_value);
  49 static gpointer g_value_object_peek_pointer             (const GValue   *value);
  50 static gchar*   g_value_object_collect_value            (GValue         *value,
  51                                                          guint           nth_value,
  52                                                          GType          *collect_type,
  53                                                          GTypeCValue    *collect_value);
  54 static gchar*   g_value_object_lcopy_value              (const GValue   *value,
  55                                                          guint           nth_value,
  56                                                          GType          *collect_type,
  57                                                          GTypeCValue    *collect_value);
  58
  59
  60 /* --- variables --- */
  61 static GQuark            quark_param_id = 0;
  62 static GQuark            quark_param_changed_queue = 0;
  63 static GQuark            quark_closure_array = 0;
  64 static GHashTable       *param_spec_hash_table = NULL;
  65
  66
  67 /* --- functions --- */
  68 #ifdef  DEBUG_OBJECTS
  69
  70 /* We need an actual method for handling debug keys in GLib.
  71  * For now, we'll simply use, as a method
  72  * 'extern gboolean glib_debug_objects'
  73  */
  74 gboolean glib_debug_objects = FALSE;
  75
  76 static guint              debug_objects_count = 0;
  77 static GHashTable        *debug_objects_ht = NULL;
  78 static void
  79 debug_objects_foreach (gpointer key,
  80                        gpointer value,
  81                        gpointer user_data)
  82 {
  83   GObject *object = value;
  84
  85   g_message ("[%p] stale %s\tref_count=%u",
  86              object,
  87              G_OBJECT_TYPE_NAME (object),
  88              object->ref_count);
  89 }
  90 static void
  91 debug_objects_atexit (void)
  92 {
  93   if (glib_debug_objects)
  94     {
  95       if (debug_objects_ht)
  96         {
  97           g_message ("stale GObjects: %u", debug_objects_count);
  98           g_hash_table_foreach (debug_objects_ht, debug_objects_foreach, NULL);
  99         }
 100     }
 101 }
 102 #endif /* DEBUG_OBJECTS */
 103
 104 void
 105 g_object_type_init (void)       /* sync with gtype.c */
 106 {
 107   static gboolean initialized = FALSE;
 108   static const GTypeFundamentalInfo finfo = {
 109     G_TYPE_FLAG_CLASSED | G_TYPE_FLAG_INSTANTIATABLE | G_TYPE_FLAG_DERIVABLE | G_TYPE_FLAG_DEEP_DERIVABLE,
 110   };
 111   static GTypeInfo info = {
 112     sizeof (GObjectClass),
 113     (GBaseInitFunc) g_object_base_class_init,
 114     (GBaseFinalizeFunc) g_object_base_class_finalize,
 115     (GClassInitFunc) g_object_do_class_init,
 116     NULL        /* class_destroy */,
 117     NULL        /* class_data */,
 118     sizeof (GObject),
 119     0           /* n_preallocs */,
 120     (GInstanceInitFunc) g_object_do_init,
 121     NULL,       /* value_table */
 122   };
 123   static const GTypeValueTable value_table = {
 124     g_value_object_init,          /* value_init */
 125     g_value_object_free_value,    /* value_free */
 126     g_value_object_copy_value,    /* value_copy */
 127     g_value_object_peek_pointer,  /* value_peek_pointer */
 128     G_VALUE_COLLECT_POINTER,      /* collect_type */
 129     g_value_object_collect_value, /* collect_value */
 130     G_VALUE_COLLECT_POINTER,      /* lcopy_type */
 131     g_value_object_lcopy_value,   /* lcopy_value */
 132   };
 133   GType type;
 134
 135   g_return_if_fail (initialized == FALSE);
 136   initialized = TRUE;
 137
 138   /* G_TYPE_OBJECT
 139    */
 140   info.value_table = &value_table;
 141   type = g_type_register_fundamental (G_TYPE_OBJECT, "GObject", &info, &finfo, 0);
 142   g_assert (type == G_TYPE_OBJECT);
 143
 144 #ifdef  DEBUG_OBJECTS
 145   g_atexit (debug_objects_atexit);
 146 #endif /* DEBUG_OBJECTS */
 147 }
 148
 149 static void
 150 g_object_base_class_init (GObjectClass *class)
 151 {
 152   /* reset instance specific fields and methods that don't get inherited */
 153   class->n_param_specs = 0;
 154   class->param_specs = NULL;
 155   class->get_param = NULL;
 156   class->set_param = NULL;
 157 }
 158
 159 static void
 160 g_object_base_class_finalize (GObjectClass *class)
 161 {
 162   guint i;
 163
 164   g_message ("finallizing base class of %s", G_OBJECT_CLASS_NAME (class));
 165
 166   for (i = 0; i < class->n_param_specs; i++)
 167     {
 168       GParamSpec *pspec = class->param_specs[i];
 169
 170       g_param_spec_hash_table_remove (param_spec_hash_table, pspec);
 171       g_param_spec_set_qdata (pspec, quark_param_id, NULL);
 172       g_param_spec_unref (pspec);
 173     }
 174   class->n_param_specs = 0;
 175   g_free (class->param_specs);
 176   class->param_specs = NULL;
 177 }
 178
 179 static void
 180 g_object_do_class_init (GObjectClass *class)
 181 {
 182   quark_param_id = g_quark_from_static_string ("glib-object-param-id");
 183   quark_param_changed_queue = g_quark_from_static_string ("glib-object-param-changed-queue");
 184   quark_closure_array = g_quark_from_static_string ("GObject-closure-array");
 185   param_spec_hash_table = g_param_spec_hash_table_new ();
 186
 187   class->queue_param_changed = g_object_do_queue_param_changed;
 188   class->dispatch_param_changed = g_object_do_dispatch_param_changed;
 189   class->shutdown = g_object_do_shutdown;
 190   class->finalize = g_object_do_finalize;
 191 }
 192
 193 void
 194 g_object_class_install_param (GObjectClass *class,
 195                               guint         param_id,
 196                               GParamSpec   *pspec /* 1 ref_count taken over */)
 197 {
 198   guint i;
 199
 200   g_return_if_fail (G_IS_OBJECT_CLASS (class));
 201   g_return_if_fail (G_IS_PARAM_SPEC (pspec));
 202   if (pspec->flags & G_PARAM_WRITABLE)
 203     g_return_if_fail (class->set_param != NULL);
 204   if (pspec->flags & G_PARAM_READABLE)
 205     g_return_if_fail (class->get_param != NULL);
 206   g_return_if_fail (param_id > 0);
 207   g_return_if_fail (PARAM_SPEC_PARAM_ID (pspec) == 0);  /* paranoid */
 208
 209   /* expensive paranoia checks ;( */
 210   for (i = 0; i < class->n_param_specs; i++)
 211     if (PARAM_SPEC_PARAM_ID (class->param_specs[i]) == param_id)
 212       {
 213         g_warning (G_STRLOC ": class `%s' already contains a parameter `%s' with id %u, "
 214                    "cannot install parameter `%s'",
 215                    G_OBJECT_CLASS_NAME (class),
 216                    class->param_specs[i]->name,
 217                    param_id,
 218                    pspec->name);
 219         return;
 220       }
 221   if (g_object_class_find_param_spec (class, pspec->name))
 222     {
 223       g_warning (G_STRLOC ": class `%s' already contains a parameter named `%s'",
 224                  G_OBJECT_CLASS_NAME (class),
 225                  pspec->name);
 226       return;
 227     }
 228
 229   g_param_spec_set_qdata (pspec, quark_param_id, GUINT_TO_POINTER (param_id));
 230   g_param_spec_hash_table_insert (param_spec_hash_table, pspec, G_OBJECT_CLASS_TYPE (class));
 231   i = class->n_param_specs++;
 232   class->param_specs = g_renew (GParamSpec*, class->param_specs, class->n_param_specs);
 233   class->param_specs[i] = pspec;
 234 }
 235
 236 GParamSpec*
 237 g_object_class_find_param_spec (GObjectClass *class,
 238                                 const gchar  *param_name)
 239 {
 240   g_return_val_if_fail (G_IS_OBJECT_CLASS (class), NULL);
 241   g_return_val_if_fail (param_name != NULL, NULL);
 242
 243   return g_param_spec_hash_table_lookup (param_spec_hash_table,
 244                                          param_name,
 245                                          G_OBJECT_CLASS_TYPE (class),
 246                                          TRUE, NULL);
 247 }
 248
 249 static void
 250 g_object_do_init (GObject *object)
 251 {
 252   object->ref_count = 1;
 253   object->qdata = NULL;
 254
 255 #ifdef  DEBUG_OBJECTS
 256   if (glib_debug_objects)
 257     {
 258       if (!debug_objects_ht)
 259         debug_objects_ht = g_hash_table_new (g_direct_hash, NULL);
 260       debug_objects_count++;
 261       g_hash_table_insert (debug_objects_ht, object, object);
 262     }
 263 #endif /* DEBUG_OBJECTS */
 264 }
 265
 266 static void
 267 g_object_last_unref (GObject *object)
 268 {
 269   g_return_if_fail (object->ref_count > 0);
 270
 271   if (object->ref_count == 1)   /* may have been re-referenced meanwhile */
 272     G_OBJECT_GET_CLASS (object)->shutdown (object);
 273
 274   object->ref_count -= 1;
 275
 276   if (object->ref_count == 0)   /* may have been re-referenced meanwhile */
 277     {
 278       G_OBJECT_GET_CLASS (object)->finalize (object);
 279       g_type_free_instance ((GTypeInstance*) object);
 280     }
 281 }
 282
 283 static void
 284 g_object_do_shutdown (GObject *object)
 285 {
 286   /* this function needs to be always present for unconditional
 287    * chaining, we also might add some code here later.
 288    * beware though, subclasses may invoke shutdown() arbitrarily.
 289    */
 290 }
 291
 292 static void
 293 g_object_do_finalize (GObject *object)
 294 {
 295   g_datalist_clear (&object->qdata);
 296
 297 #ifdef  DEBUG_OBJECTS
 298   if (glib_debug_objects)
 299     {
 300       g_assert (g_hash_table_lookup (debug_objects_ht, object) == object);
 301
 302       g_hash_table_remove (debug_objects_ht, object);
 303       debug_objects_count--;
 304     }
 305 #endif /* DEBUG_OBJECTS */
 306 }
 307
 308 gpointer
 309 g_object_new (GType        object_type,
 310               const gchar *first_param_name,
 311               ...)
 312 {
 313   GObject *object;
 314   va_list var_args;
 315
 316   g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
 317
 318   va_start (var_args, first_param_name);
 319   object = g_object_new_valist (object_type, first_param_name, var_args);
 320   va_end (var_args);
 321
 322   return object;
 323 }
 324
 325 gpointer
 326 g_object_new_valist (GType        object_type,
 327                      const gchar *first_param_name,
 328                      va_list      var_args)
 329 {
 330   GObject *object;
 331
 332   g_return_val_if_fail (G_TYPE_IS_OBJECT (object_type), NULL);
 333
 334   object = (GObject*) g_type_create_instance (object_type);
 335   if (first_param_name)
 336     g_object_set_valist (object, first_param_name, var_args);
 337
 338   return object;
 339 }
 340
 341 static void
 342 g_object_do_dispatch_param_changed (GObject    *object,
 343                                     GParamSpec *pspec)
 344 {
 345 /*  g_message ("NOTIFICATION: parameter `%s' changed on object `%s'",
 346              pspec->name,
 347              G_OBJECT_TYPE_NAME (object));*/
 348 }
 349
 350 static gboolean
 351 notify_param_changed_handler (gpointer data)
 352 {
 353   GObject *object;
 354   GObjectClass *class;
 355   GSList *slist;
 356
 357   /* FIXME: need GDK_THREADS lock */
 358
 359   object = G_OBJECT (data);
 360   class = G_OBJECT_GET_CLASS (object);
 361   slist = g_datalist_id_get_data (&object->qdata, quark_param_changed_queue);
 362
 363   /* a reference count is still being held */
 364
 365   for (; slist; slist = slist->next)
 366     if (slist->data)
 367       {
 368         GParamSpec *pspec = slist->data;
 369
 370         slist->data = NULL;
 371         class->dispatch_param_changed (object, pspec);
 372       }
 373
 374   g_datalist_id_set_data (&object->qdata, quark_param_changed_queue, NULL);
 375
 376   return FALSE;
 377 }
 378
 379 static void
 380 g_object_do_queue_param_changed (GObject    *object,
 381                                  GParamSpec *pspec)
 382 {
 383   GSList *slist, *last = NULL;
 384
 385   /* if this is a recursive call on this object (i.e. pspecs are queued
 386    * for notification, while param_changed notification is currently in
 387    * progress), we simply add them to the queue that is currently being
 388    * dispatched. otherwise, we later dispatch parameter changed notification
 389    * asyncronously from an idle handler untill the queue is completely empty.
 390    */
 391
 392   slist = g_datalist_id_get_data (&object->qdata, quark_param_changed_queue);
 393   for (; slist; last = slist, slist = last->next)
 394     if (slist->data == pspec)
 395       return;
 396
 397   if (!last)
 398     {
 399       g_object_ref (object);
 400       g_idle_add_full (G_NOTIFY_PRIORITY,
 401                        notify_param_changed_handler,
 402                        object,
 403                        (GDestroyNotify) g_object_unref);
 404       g_object_set_qdata_full (object,
 405                                quark_param_changed_queue,
 406                                g_slist_prepend (NULL, pspec),
 407                                (GDestroyNotify) g_slist_free);
 408     }
 409   else
 410     last->next = g_slist_prepend (NULL, pspec);
 411 }
 412
 413 static inline void
 414 object_get_param (GObject     *object,
 415                   GValue      *value,
 416                   GParamSpec  *pspec,
 417                   const gchar *trailer)
 418 {
 419   GObjectClass *class;
 420
 421   g_return_if_fail (g_type_is_a (G_OBJECT_TYPE (object), pspec->owner_type));   /* paranoid */
 422
 423   class = g_type_class_peek (pspec->owner_type);
 424
 425   class->get_param (object, PARAM_SPEC_PARAM_ID (pspec), value, pspec, trailer);
 426 }
 427
 428 static inline void
 429 object_set_param (GObject     *object,
 430                   GValue      *value,
 431                   GParamSpec  *pspec,
 432                   const gchar *trailer)
 433 {
 434   GObjectClass *class;
 435
 436   g_return_if_fail (g_type_is_a (G_OBJECT_TYPE (object), pspec->owner_type));   /* paranoid */
 437
 438   class = g_type_class_peek (pspec->owner_type);
 439
 440   class->set_param (object, PARAM_SPEC_PARAM_ID (pspec), value, pspec, trailer);
 441
 442   class->queue_param_changed (object, pspec);
 443 }
 444
 445 void
 446 g_object_set_valist (GObject     *object,
 447                      const gchar *first_param_name,
 448                      va_list      var_args)
 449 {
 450   const gchar *name;
 451
 452   g_return_if_fail (G_IS_OBJECT (object));
 453
 454   g_object_ref (object);
 455
 456   name = first_param_name;
 457
 458   while (name)
 459     {
 460       const gchar *trailer = NULL;
 461       GValue value = { 0, };
 462       GParamSpec *pspec;
 463       gchar *error = NULL;
 464
 465       pspec = g_param_spec_hash_table_lookup (param_spec_hash_table,
 466                                               name,
 467                                               G_OBJECT_TYPE (object),
 468                                               TRUE,
 469                                               &trailer);
 470       if (!pspec)
 471         {
 472           g_warning ("%s: object class `%s' has no parameter named `%s'",
 473                      G_STRLOC,
 474                      G_OBJECT_TYPE_NAME (object),
 475                      name);
 476           break;
 477         }
 478       if (!(pspec->flags & G_PARAM_WRITABLE))
 479         {
 480           g_warning ("%s: parameter `%s' of object class `%s' is not writable",
 481                      G_STRLOC,
 482                      pspec->name,
 483                      G_OBJECT_TYPE_NAME (object));
 484           break;
 485         }
 486
 487       g_value_init (&value, G_PARAM_SPEC_VALUE_TYPE (pspec));
 488
 489       G_VALUE_COLLECT (&value, var_args, &error);
 490       if (error)
 491         {
 492           g_warning ("%s: %s", G_STRLOC, error);
 493           g_free (error);
 494
 495           /* we purposely leak the value here, it might not be
 496            * in a sane state if an error condition occoured
 497            */
 498           break;
 499         }
 500
 501       object_set_param (object, &value, pspec, trailer);
 502
 503       g_value_unset (&value);
 504
 505       name = va_arg (var_args, gchar*);
 506     }
 507
 508   g_object_unref (object);
 509 }
 510
 511 void
 512 g_object_get_valist (GObject     *object,
 513                      const gchar *first_param_name,
 514                      va_list      var_args)
 515 {
 516   const gchar *name;
 517
 518   g_return_if_fail (G_IS_OBJECT (object));
 519
 520   g_object_ref (object);
 521
 522   name = first_param_name;
 523
 524   while (name)
 525     {
 526       const gchar *trailer = NULL;
 527       GValue value = { 0, };
 528       GParamSpec *pspec;
 529       gchar *error = NULL;
 530
 531       pspec = g_param_spec_hash_table_lookup (param_spec_hash_table,
 532                                               name,
 533                                               G_OBJECT_TYPE (object),
 534                                               TRUE,
 535                                               &trailer);
 536       if (!pspec)
 537         {
 538           g_warning ("%s: object class `%s' has no parameter named `%s'",
 539                      G_STRLOC,
 540                      G_OBJECT_TYPE_NAME (object),
 541                      name);
 542           break;
 543         }
 544       if (!(pspec->flags & G_PARAM_READABLE))
 545         {
 546           g_warning ("%s: parameter `%s' of object class `%s' is not readable",
 547                      G_STRLOC,
 548                      pspec->name,
 549                      G_OBJECT_TYPE_NAME (object));
 550           break;
 551         }
 552
 553       g_value_init (&value, G_PARAM_SPEC_VALUE_TYPE (pspec));
 554
 555       object_get_param (object, &value, pspec, trailer);
 556
 557       G_VALUE_LCOPY (&value, var_args, &error);
 558       if (error)
 559         {
 560           g_warning ("%s: %s", G_STRLOC, error);
 561           g_free (error);
 562
 563           /* we purposely leak the value here, it might not be
 564            * in a sane state if an error condition occoured
 565            */
 566           break;
 567         }
 568
 569       g_value_unset (&value);
 570
 571       name = va_arg (var_args, gchar*);
 572     }
 573
 574   g_object_unref (object);
 575 }
 576
 577 void
 578 g_object_set (GObject     *object,
 579               const gchar *first_param_name,
 580               ...)
 581 {
 582   va_list var_args;
 583
 584   g_return_if_fail (G_IS_OBJECT (object));
 585
 586   va_start (var_args, first_param_name);
 587   g_object_set_valist (object, first_param_name, var_args);
 588   va_end (var_args);
 589 }
 590
 591 void
 592 g_object_get (GObject     *object,
 593               const gchar *first_param_name,
 594               ...)
 595 {
 596   va_list var_args;
 597
 598   g_return_if_fail (G_IS_OBJECT (object));
 599
 600   va_start (var_args, first_param_name);
 601   g_object_get_valist (object, first_param_name, var_args);
 602   va_end (var_args);
 603 }
 604
 605 void
 606 g_object_set_param (GObject      *object,
 607                     const gchar  *param_name,
 608                     const GValue *value)
 609 {
 610   GParamSpec *pspec;
 611   const gchar *trailer;
 612
 613   g_return_if_fail (G_IS_OBJECT (object));
 614   g_return_if_fail (param_name != NULL);
 615   g_return_if_fail (G_IS_VALUE (value));
 616
 617   g_object_ref (object);
 618
 619   pspec = g_param_spec_hash_table_lookup (param_spec_hash_table,
 620                                           param_name,
 621                                           G_OBJECT_TYPE (object),
 622                                           TRUE,
 623                                           &trailer);
 624   if (!pspec)
 625     g_warning ("%s: object class `%s' has no parameter named `%s'",
 626                G_STRLOC,
 627                G_OBJECT_TYPE_NAME (object),
 628                param_name);
 629   else
 630     {
 631       GValue tmp_value = { 0, };
 632
 633       /* provide a copy to work from and convert if necessary */
 634       g_value_init (&tmp_value, G_PARAM_SPEC_VALUE_TYPE (pspec));
 635
 636       if (!g_value_convert (value, &tmp_value) ||
 637           g_param_value_validate (pspec, &tmp_value))
 638         g_warning ("%s: cannot convert `%s' value to parameter `%s' value of type `%s'",
 639                    G_STRLOC,
 640                    G_VALUE_TYPE_NAME (value),
 641                    pspec->name,
 642                    g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspec)));
 643       else
 644         object_set_param (object, &tmp_value, pspec, trailer);
 645
 646       g_value_unset (&tmp_value);
 647     }
 648
 649   g_object_unref (object);
 650 }
 651
 652 void
 653 g_object_get_param (GObject     *object,
 654                     const gchar *param_name,
 655                     GValue      *value)
 656 {
 657   GParamSpec *pspec;
 658   const gchar *trailer;
 659
 660   g_return_if_fail (G_IS_OBJECT (object));
 661   g_return_if_fail (param_name != NULL);
 662   g_return_if_fail (G_IS_VALUE (value));
 663
 664   g_object_ref (object);
 665
 666   pspec = g_param_spec_hash_table_lookup (param_spec_hash_table,
 667                                           param_name,
 668                                           G_OBJECT_TYPE (object),
 669                                           TRUE,
 670                                           &trailer);
 671   if (!pspec)
 672     g_warning ("%s: object class `%s' has no parameter named `%s'",
 673                G_STRLOC,
 674                G_OBJECT_TYPE_NAME (object),
 675                param_name);
 676   else
 677     {
 678       GValue tmp_value = { 0, };
 679
 680       /* provide a copy to work from and later convert if necessary, so
 681        * _get_param() implementations need *not* care about freeing values
 682        * that might be already set in the parameter to get.
 683        * (though, at this point, GValue should exclusively be modified
 684        * through the accessor functions anyways)
 685        */
 686       g_value_init (&tmp_value, G_PARAM_SPEC_VALUE_TYPE (pspec));
 687
 688       if (!g_value_types_exchangable (G_VALUE_TYPE (value), G_PARAM_SPEC_VALUE_TYPE (pspec)))
 689         g_warning ("%s: can't retrive parameter `%s' value of type `%s' as value of type `%s'",
 690                    G_STRLOC,
 691                    pspec->name,
 692                    g_type_name (G_PARAM_SPEC_VALUE_TYPE (pspec)),
 693                    G_VALUE_TYPE_NAME (value));
 694       else
 695         {
 696           object_get_param (object, &tmp_value, pspec, trailer);
 697           g_value_convert (&tmp_value, value);
 698           /* g_value_validate (value, pspec); */
 699         }
 700
 701       g_value_unset (&tmp_value);
 702     }
 703
 704   g_object_unref (object);
 705 }
 706
 707 void
 708 g_object_queue_param_changed (GObject     *object,
 709                               const gchar *param_name)
 710 {
 711   GParamSpec *pspec;
 712
 713   g_return_if_fail (G_IS_OBJECT (object));
 714   g_return_if_fail (param_name != NULL);
 715
 716   pspec = g_param_spec_hash_table_lookup (param_spec_hash_table,
 717                                           param_name,
 718                                           G_OBJECT_TYPE (object),
 719                                           TRUE, NULL);
 720   if (!pspec)
 721     g_warning ("%s: object class `%s' has no parameter named `%s'",
 722                G_STRLOC,
 723                G_OBJECT_TYPE_NAME (object),
 724                param_name);
 725   else
 726     G_OBJECT_GET_CLASS (object)->queue_param_changed (object, pspec);
 727 }
 728
 729 GObject*
 730 g_object_ref (GObject *object)
 731 {
 732   g_return_val_if_fail (G_IS_OBJECT (object), NULL);
 733   g_return_val_if_fail (object->ref_count > 0, NULL);
 734
 735   object->ref_count += 1;
 736
 737   return object;
 738 }
 739
 740 void
 741 g_object_unref (GObject *object)
 742 {
 743   g_return_if_fail (G_IS_OBJECT (object));
 744   g_return_if_fail (object->ref_count > 0);
 745
 746   if (object->ref_count > 1)
 747     object->ref_count -= 1;
 748   else
 749     g_object_last_unref (object);
 750 }
 751
 752 gpointer
 753 g_object_get_qdata (GObject *object,
 754                     GQuark   quark)
 755 {
 756   g_return_val_if_fail (G_IS_OBJECT (object), NULL);
 757
 758   return quark ? g_datalist_id_get_data (&object->qdata, quark) : NULL;
 759 }
 760
 761 void
 762 g_object_set_qdata (GObject *object,
 763                     GQuark   quark,
 764                     gpointer data)
 765 {
 766   g_return_if_fail (G_IS_OBJECT (object));
 767   g_return_if_fail (quark > 0);
 768
 769   g_datalist_id_set_data (&object->qdata, quark, data);
 770 }
 771
 772 void
 773 g_object_set_qdata_full (GObject       *object,
 774                          GQuark         quark,
 775                          gpointer       data,
 776                          GDestroyNotify destroy)
 777 {
 778   g_return_if_fail (G_IS_OBJECT (object));
 779   g_return_if_fail (quark > 0);
 780
 781   g_datalist_id_set_data_full (&object->qdata, quark, data, data ? destroy : NULL);
 782 }
 783
 784 gpointer
 785 g_object_steal_qdata (GObject *object,
 786                       GQuark   quark)
 787 {
 788   g_return_val_if_fail (G_IS_OBJECT (object), NULL);
 789   g_return_val_if_fail (quark > 0, NULL);
 790
 791   return g_datalist_id_remove_no_notify (&object->qdata, quark);
 792 }
 793
 794 static void
 795 g_value_object_init (GValue *value)
 796 {
 797   value->data[0].v_pointer = NULL;
 798 }
 799
 800 static void
 801 g_value_object_free_value (GValue *value)
 802 {
 803   if (value->data[0].v_pointer)
 804     g_object_unref (value->data[0].v_pointer);
 805 }
 806
 807 static void
 808 g_value_object_copy_value (const GValue *src_value,
 809                            GValue       *dest_value)
 810 {
 811   if (src_value->data[0].v_pointer)
 812     dest_value->data[0].v_pointer = g_object_ref (src_value->data[0].v_pointer);
 813   else
 814     dest_value->data[0].v_pointer = NULL;
 815 }
 816
 817 static gpointer
 818 g_value_object_peek_pointer (const GValue *value)
 819 {
 820   return value->data[0].v_pointer;
 821 }
 822
 823 static gchar*
 824 g_value_object_collect_value (GValue      *value,
 825                               guint        nth_value,
 826                               GType       *collect_type,
 827                               GTypeCValue *collect_value)
 828 {
 829   if (collect_value->v_pointer)
 830     {
 831       GObject *object = collect_value->v_pointer;
 832
 833       if (object->g_type_instance.g_class == NULL)
 834         return g_strconcat ("invalid unclassed object pointer for value type `",
 835                             G_VALUE_TYPE_NAME (value),
 836                             "'",
 837                             NULL);
 838       else if (!g_type_is_a (G_OBJECT_TYPE (object), G_VALUE_TYPE (value)))
 839         return g_strconcat ("invalid object type `",
 840                             G_OBJECT_TYPE_NAME (object),
 841                             "' for value type `",
 842                             G_VALUE_TYPE_NAME (value),
 843                             "'",
 844                             NULL);
 845       value->data[0].v_pointer = g_object_ref (object);
 846     }
 847   else
 848     value->data[0].v_pointer = NULL;
 849
 850   *collect_type = 0;
 851   return NULL;
 852 }
 853
 854 static gchar*
 855 g_value_object_lcopy_value (const GValue *value,
 856                             guint         nth_value,
 857                             GType        *collect_type,
 858                             GTypeCValue  *collect_value)
 859 {
 860   GObject **object_p = collect_value->v_pointer;
 861
 862   if (!object_p)
 863     return g_strdup_printf ("value location for `%s' passed as NULL", G_VALUE_TYPE_NAME (value));
 864
 865   *object_p = value->data[0].v_pointer ? g_object_ref (value->data[0].v_pointer) : NULL;
 866
 867   *collect_type = 0;
 868   return NULL;
 869 }
 870
 871 void
 872 g_value_set_object (GValue  *value,
 873                     GObject *v_object)
 874 {
 875   g_return_if_fail (G_IS_VALUE_OBJECT (value));
 876   if (v_object)
 877     g_return_if_fail (G_IS_OBJECT (v_object));
 878
 879   if (value->data[0].v_pointer)
 880     g_object_unref (value->data[0].v_pointer);
 881   value->data[0].v_pointer = v_object;
 882   if (value->data[0].v_pointer)
 883     g_object_ref (value->data[0].v_pointer);
 884 }
 885
 886 GObject*
 887 g_value_get_object (const GValue *value)
 888 {
 889   g_return_val_if_fail (G_IS_VALUE_OBJECT (value), NULL);
 890
 891   return value->data[0].v_pointer;
 892 }
 893
 894 GObject*
 895 g_value_dup_object (const GValue *value)
 896 {
 897   g_return_val_if_fail (G_IS_VALUE_OBJECT (value), NULL);
 898
 899   return value->data[0].v_pointer ? g_object_ref (value->data[0].v_pointer) : NULL;
 900 }
 901
 902 typedef struct {
 903   GObject  *object;
 904   guint     n_closures;
 905   GClosure *closures[1]; /* flexible array */
 906 } CArray;
 907
 908 static void
 909 object_remove_closure (gpointer  data,
 910                        GClosure *closure)
 911 {
 912   GObject *object = data;
 913   CArray *carray = g_object_get_qdata (object, quark_closure_array);
 914   guint i;
 915
 916   for (i = 0; i < carray->n_closures; i++)
 917     if (carray->closures[i] == closure)
 918       {
 919         carray->n_closures--;
 920         if (i < carray->n_closures)
 921           carray->closures[i] = carray->closures[carray->n_closures];
 922         return;
 923       }
 924   g_assert_not_reached ();
 925 }
 926
 927 static void
 928 destroy_closure_array (gpointer data)
 929 {
 930   CArray *carray = data;
 931   GObject *object = carray->object;
 932   guint i, n = carray->n_closures;
 933
 934   for (i = 0; i < n; i++)
 935     {
 936       GClosure *closure = carray->closures[i];
 937
 938       /* removing object_remove_closure() upfront is probably faster than
 939        * letting it fiddle with quark_closure_array which is empty anyways
 940        */
 941       g_closure_remove_inotify (closure, object, object_remove_closure);
 942       g_closure_invalidate (closure);
 943     }
 944   g_free (carray);
 945 }
 946
 947 void
 948 g_object_watch_closure (GObject  *object,
 949                         GClosure *closure)
 950 {
 951   CArray *carray;
 952
 953   g_return_if_fail (G_IS_OBJECT (object));
 954   g_return_if_fail (closure != NULL);
 955   g_return_if_fail (closure->is_invalid == FALSE);
 956   g_return_if_fail (closure->in_marshal == FALSE);
 957   g_return_if_fail (object->ref_count > 0);     /* this doesn't work on finalizing objects */
 958
 959   g_closure_add_inotify (closure, object, object_remove_closure);
 960   g_closure_add_marshal_guards (closure,
 961                                 object, (GClosureNotify) g_object_ref,
 962                                 object, (GClosureNotify) g_object_unref);
 963   carray = g_object_steal_qdata (object, quark_closure_array);
 964   if (!carray)
 965     {
 966       carray = g_renew (CArray, NULL, 1);
 967       carray->object = object;
 968       carray->n_closures = 1;
 969       carray->closures[0] = closure;
 970       g_object_set_qdata_full (object, quark_closure_array, carray, destroy_closure_array);
 971     }
 972   else
 973     {
 974       guint i = carray->n_closures++;
 975
 976       carray = g_realloc (carray, sizeof (*carray) + sizeof (carray->closures[0]) * i);
 977       carray->closures[i] = closure;
 978       g_object_set_qdata_full (object, quark_closure_array, carray, destroy_closure_array);
 979     }
 980 }
 981
 982 GClosure*
 983 g_closure_new_object (guint    sizeof_closure,
 984                       GObject *object)
 985 {
 986   GClosure *closure;
 987
 988   g_return_val_if_fail (G_IS_OBJECT (object), NULL);
 989   g_return_val_if_fail (object->ref_count > 0, NULL);     /* this doesn't work on finalizing objects */
 990
 991   closure = g_closure_new_simple (sizeof_closure, object);
 992   g_object_watch_closure (object, closure);
 993
 994   return closure;
 995 }
 996
 997 GClosure*
 998 g_cclosure_new_object (gpointer  _object,
 999                        GCallback callback_func)
1000 {
1001   GObject *object = _object;
1002   GClosure *closure;
1003
1004   g_return_val_if_fail (G_IS_OBJECT (object), NULL);
1005   g_return_val_if_fail (object->ref_count > 0, NULL);     /* this doesn't work on finalizing objects */
1006   g_return_val_if_fail (callback_func != NULL, NULL);
1007
1008   closure = g_cclosure_new (callback_func, object, NULL);
1009   g_object_watch_closure (object, closure);
1010
1011   return closure;
1012 }
1013
1014 GClosure*
1015 g_cclosure_new_object_swap (gpointer  _object,
1016                             GCallback callback_func)
1017 {
1018   GObject *object = _object;
1019   GClosure *closure;
1020
1021   g_return_val_if_fail (G_IS_OBJECT (object), NULL);
1022   g_return_val_if_fail (object->ref_count > 0, NULL);     /* this doesn't work on finalizing objects */
1023   g_return_val_if_fail (callback_func != NULL, NULL);
1024
1025   closure = g_cclosure_new_swap (callback_func, object, NULL);
1026   g_object_watch_closure (object, closure);
1027
1028   return closure;
1029 }