gobject/gclosure.c - third_party/glib - Git at Google

 /* GObject - GLib Type, Object, Parameter and Signal Library
  * Copyright (C) 2000-2001 Red Hat, Inc.
  * Copyright (C) 2005 Imendio AB
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General
  * Public License along with this library; if not, write to the
  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  * Boston, MA 02111-1307, USA.
  */
 #include	"gclosure.h"

 /*
  * MT safe with regards to reference counting.
  */

 #include	"gvalue.h"
 #include 	"gobjectalias.h"
 #include	<string.h>


 #define	CLOSURE_MAX_REF_COUNT		((1 << 15) - 1)
 #define	CLOSURE_MAX_N_GUARDS		((1 << 1) - 1)
 #define	CLOSURE_MAX_N_FNOTIFIERS	((1 << 2) - 1)
 #define	CLOSURE_MAX_N_INOTIFIERS	((1 << 8) - 1)
 #define	CLOSURE_N_MFUNCS(cl)		((cl)->meta_marshal + \
                                          ((cl)->n_guards << 1L))
 /* same as G_CLOSURE_N_NOTIFIERS() (keep in sync) */
 #define	CLOSURE_N_NOTIFIERS(cl)		(CLOSURE_N_MFUNCS (cl) + \
                                          (cl)->n_fnotifiers + \
                                          (cl)->n_inotifiers)

 typedef union {
   GClosure closure;
   volatile gint vint;
 } ClosureInt;

 #define CHANGE_FIELD(_closure, _field, _OP, _value, _must_set, _SET_OLD, _SET_NEW)      \
 G_STMT_START {                                                                          \
   ClosureInt *cunion = (ClosureInt*) _closure;                 		                \
   gint new_int, old_int, success;                              		                \
   do                                                    		                \
     {                                                   		                \
       ClosureInt tmp;                                   		                \
       tmp.vint = old_int = cunion->vint;                		                \
       _SET_OLD tmp.closure._field;                                                      \
       tmp.closure._field _OP _value;                      		                \
       _SET_NEW tmp.closure._field;                                                      \
       new_int = tmp.vint;                               		                \
       success = g_atomic_int_compare_and_exchange (&cunion->vint, old_int, new_int);    \
     }                                                   		                \
   while (!success && _must_set);                                                        \
 } G_STMT_END

 #define SWAP(_closure, _field, _value, _oldv)   CHANGE_FIELD (_closure, _field, =, _value, TRUE, *(_oldv) =,     (void) )
 #define SET(_closure, _field, _value)           CHANGE_FIELD (_closure, _field, =, _value, TRUE,     (void),     (void) )
 #define INC(_closure, _field)                   CHANGE_FIELD (_closure, _field, +=,     1, TRUE,     (void),     (void) )
 #define INC_ASSIGN(_closure, _field, _newv)     CHANGE_FIELD (_closure, _field, +=,     1, TRUE,     (void), *(_newv) = )
 #define DEC(_closure, _field)                   CHANGE_FIELD (_closure, _field, -=,     1, TRUE,     (void),     (void) )
 #define DEC_ASSIGN(_closure, _field, _newv)     CHANGE_FIELD (_closure, _field, -=,     1, TRUE,     (void), *(_newv) = )

 #if 0   /* for non-thread-safe closures */
 #define SWAP(cl,f,v,o)     (void) (*(o) = cl->f, cl->f = v)
 #define SET(cl,f,v)        (void) (cl->f = v)
 #define INC(cl,f)          (void) (cl->f += 1)
 #define INC_ASSIGN(cl,f,n) (void) (cl->f += 1, *(n) = cl->f)
 #define DEC(cl,f)          (void) (cl->f -= 1)
 #define DEC_ASSIGN(cl,f,n) (void) (cl->f -= 1, *(n) = cl->f)
 #endif

 enum {
   FNOTIFY,
   INOTIFY,
   PRE_NOTIFY,
   POST_NOTIFY
 };


 /* --- functions --- */
 GClosure*
 g_closure_new_simple (guint           sizeof_closure,
 		      gpointer        data)
 {
   GClosure *closure;

   g_return_val_if_fail (sizeof_closure >= sizeof (GClosure), NULL);

   closure = g_malloc0 (sizeof_closure);
   SET (closure, ref_count, 1);
   SET (closure, meta_marshal, 0);
   SET (closure, n_guards, 0);
   SET (closure, n_fnotifiers, 0);
   SET (closure, n_inotifiers, 0);
   SET (closure, in_inotify, FALSE);
   SET (closure, floating, TRUE);
   SET (closure, derivative_flag, 0);
   SET (closure, in_marshal, FALSE);
   SET (closure, is_invalid, FALSE);
   closure->marshal = NULL;
   closure->data = data;
   closure->notifiers = NULL;
   memset (G_STRUCT_MEMBER_P (closure, sizeof (*closure)), 0, sizeof_closure - sizeof (*closure));

   return closure;
 }

 static inline void
 closure_invoke_notifiers (GClosure *closure,
 			  guint     notify_type)
 {
   /* notifier layout:
    *     meta_marshal  n_guards    n_guards     n_fnotif.  n_inotifiers
    * ->[[meta_marshal][pre_guards][post_guards][fnotifiers][inotifiers]]
    *
    * CLOSURE_N_MFUNCS(cl)    = meta_marshal + n_guards + n_guards;
    * CLOSURE_N_NOTIFIERS(cl) = CLOSURE_N_MFUNCS(cl) + n_fnotifiers + n_inotifiers
    *
    * constrains/catches:
    * - closure->notifiers may be reloacted during callback
    * - closure->n_fnotifiers and closure->n_inotifiers may change during callback
    * - i.e. callbacks can be removed/added during invocation
    * - must prepare for callback removal during FNOTIFY and INOTIFY (done via ->marshal= & ->data=)
    * - must distinguish (->marshal= & ->data=) for INOTIFY vs. FNOTIFY (via ->in_inotify)
    * + closure->n_guards is const during PRE_NOTIFY & POST_NOTIFY
    * + closure->meta_marshal is const for all cases
    * + none of the callbacks can cause recursion
    * + closure->n_inotifiers is const 0 during FNOTIFY
    */
   switch (notify_type)
     {
       GClosureNotifyData *ndata;
       guint i, offs;
     case FNOTIFY:
       while (closure->n_fnotifiers)
 	{
           guint n;
 	  DEC_ASSIGN (closure, n_fnotifiers, &n);

 	  ndata = closure->notifiers + CLOSURE_N_MFUNCS (closure) + n;
 	  closure->marshal = (GClosureMarshal) ndata->notify;
 	  closure->data = ndata->data;
 	  ndata->notify (ndata->data, closure);
 	}
       closure->marshal = NULL;
       closure->data = NULL;
       break;
     case INOTIFY:
       SET (closure, in_inotify, TRUE);
       while (closure->n_inotifiers)
 	{
           guint n;
           DEC_ASSIGN (closure, n_inotifiers, &n);

 	  ndata = closure->notifiers + CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + n;
 	  closure->marshal = (GClosureMarshal) ndata->notify;
 	  closure->data = ndata->data;
 	  ndata->notify (ndata->data, closure);
 	}
       closure->marshal = NULL;
       closure->data = NULL;
       SET (closure, in_inotify, FALSE);
       break;
     case PRE_NOTIFY:
       i = closure->n_guards;
       offs = closure->meta_marshal;
       while (i--)
 	{
 	  ndata = closure->notifiers + offs + i;
 	  ndata->notify (ndata->data, closure);
 	}
       break;
     case POST_NOTIFY:
       i = closure->n_guards;
       offs = closure->meta_marshal + i;
       while (i--)
 	{
 	  ndata = closure->notifiers + offs + i;
 	  ndata->notify (ndata->data, closure);
 	}
       break;
     }
 }

 void
 g_closure_set_meta_marshal (GClosure       *closure,
 			    gpointer        marshal_data,
 			    GClosureMarshal meta_marshal)
 {
   GClosureNotifyData *notifiers;

   g_return_if_fail (closure != NULL);
   g_return_if_fail (meta_marshal != NULL);
   g_return_if_fail (closure->is_invalid == FALSE);
   g_return_if_fail (closure->in_marshal == FALSE);
   g_return_if_fail (closure->meta_marshal == 0);

   notifiers = closure->notifiers;
   closure->notifiers = g_renew (GClosureNotifyData, NULL, CLOSURE_N_NOTIFIERS (closure) + 1);
   if (notifiers)
     {
       /* usually the meta marshal will be setup right after creation, so the
        * g_memmove() should be rare-case scenario
        */
       g_memmove (closure->notifiers + 1, notifiers, CLOSURE_N_NOTIFIERS (closure) * sizeof (notifiers[0]));
       g_free (notifiers);
     }
   closure->notifiers[0].data = marshal_data;
   closure->notifiers[0].notify = (GClosureNotify) meta_marshal;
   SET (closure, meta_marshal, 1);
 }

 void
 g_closure_add_marshal_guards (GClosure      *closure,
 			      gpointer       pre_marshal_data,
 			      GClosureNotify pre_marshal_notify,
 			      gpointer       post_marshal_data,
 			      GClosureNotify post_marshal_notify)
 {
   guint i;

   g_return_if_fail (closure != NULL);
   g_return_if_fail (pre_marshal_notify != NULL);
   g_return_if_fail (post_marshal_notify != NULL);
   g_return_if_fail (closure->is_invalid == FALSE);
   g_return_if_fail (closure->in_marshal == FALSE);
   g_return_if_fail (closure->n_guards < CLOSURE_MAX_N_GUARDS);

   closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 2);
   if (closure->n_inotifiers)
     closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
 			closure->n_fnotifiers +
 			closure->n_inotifiers + 1)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
 									  closure->n_fnotifiers + 0)];
   if (closure->n_inotifiers > 1)
     closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
 			closure->n_fnotifiers +
 			closure->n_inotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
 								      closure->n_fnotifiers + 1)];
   if (closure->n_fnotifiers)
     closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
 			closure->n_fnotifiers + 1)] = closure->notifiers[CLOSURE_N_MFUNCS (closure) + 0];
   if (closure->n_fnotifiers > 1)
     closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
 			closure->n_fnotifiers)] = closure->notifiers[CLOSURE_N_MFUNCS (closure) + 1];
   if (closure->n_guards)
     closure->notifiers[(closure->meta_marshal +
 			closure->n_guards +
 			closure->n_guards + 1)] = closure->notifiers[closure->meta_marshal + closure->n_guards];
   i = closure->n_guards;
   closure->notifiers[closure->meta_marshal + i].data = pre_marshal_data;
   closure->notifiers[closure->meta_marshal + i].notify = pre_marshal_notify;
   closure->notifiers[closure->meta_marshal + i + 1].data = post_marshal_data;
   closure->notifiers[closure->meta_marshal + i + 1].notify = post_marshal_notify;
   INC (closure, n_guards);
 }

 void
 g_closure_add_finalize_notifier (GClosure      *closure,
 				 gpointer       notify_data,
 				 GClosureNotify notify_func)
 {
   guint i;

   g_return_if_fail (closure != NULL);
   g_return_if_fail (notify_func != NULL);
   g_return_if_fail (closure->n_fnotifiers < CLOSURE_MAX_N_FNOTIFIERS);

   closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 1);
   if (closure->n_inotifiers)
     closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
 			closure->n_fnotifiers +
 			closure->n_inotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
 								      closure->n_fnotifiers + 0)];
   i = CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers;
   closure->notifiers[i].data = notify_data;
   closure->notifiers[i].notify = notify_func;
   INC (closure, n_fnotifiers);
 }

 void
 g_closure_add_invalidate_notifier (GClosure      *closure,
 				   gpointer       notify_data,
 				   GClosureNotify notify_func)
 {
   guint i;

   g_return_if_fail (closure != NULL);
   g_return_if_fail (notify_func != NULL);
   g_return_if_fail (closure->is_invalid == FALSE);
   g_return_if_fail (closure->n_inotifiers < CLOSURE_MAX_N_INOTIFIERS);

   closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 1);
   i = CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + closure->n_inotifiers;
   closure->notifiers[i].data = notify_data;
   closure->notifiers[i].notify = notify_func;
   INC (closure, n_inotifiers);
 }

 static inline gboolean
 closure_try_remove_inotify (GClosure       *closure,
 			    gpointer       notify_data,
 			    GClosureNotify notify_func)
 {
   GClosureNotifyData *ndata, *nlast;

   nlast = closure->notifiers + CLOSURE_N_NOTIFIERS (closure) - 1;
   for (ndata = nlast + 1 - closure->n_inotifiers; ndata <= nlast; ndata++)
     if (ndata->notify == notify_func && ndata->data == notify_data)
       {
 	DEC (closure, n_inotifiers);
 	if (ndata < nlast)
 	  *ndata = *nlast;

 	return TRUE;
       }
   return FALSE;
 }

 static inline gboolean
 closure_try_remove_fnotify (GClosure       *closure,
 			    gpointer       notify_data,
 			    GClosureNotify notify_func)
 {
   GClosureNotifyData *ndata, *nlast;

   nlast = closure->notifiers + CLOSURE_N_NOTIFIERS (closure) - closure->n_inotifiers - 1;
   for (ndata = nlast + 1 - closure->n_fnotifiers; ndata <= nlast; ndata++)
     if (ndata->notify == notify_func && ndata->data == notify_data)
       {
 	DEC (closure, n_fnotifiers);
 	if (ndata < nlast)
 	  *ndata = *nlast;
 	if (closure->n_inotifiers)
 	  closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
 			      closure->n_fnotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
 									    closure->n_fnotifiers +
 									    closure->n_inotifiers)];
 	return TRUE;
       }
   return FALSE;
 }

 GClosure*
 g_closure_ref (GClosure *closure)
 {
   guint new_ref_count;
   g_return_val_if_fail (closure != NULL, NULL);
   g_return_val_if_fail (closure->ref_count > 0, NULL);
   g_return_val_if_fail (closure->ref_count < CLOSURE_MAX_REF_COUNT, NULL);

   INC_ASSIGN (closure, ref_count, &new_ref_count);
   g_return_val_if_fail (new_ref_count > 1, NULL);

   return closure;
 }

 void
 g_closure_invalidate (GClosure *closure)
 {
   g_return_if_fail (closure != NULL);

   if (!closure->is_invalid)
     {
       gboolean was_invalid;
       g_closure_ref (closure);           /* preserve floating flag */
       SWAP (closure, is_invalid, TRUE, &was_invalid);
       /* invalidate only once */
       if (!was_invalid)
         closure_invoke_notifiers (closure, INOTIFY);
       g_closure_unref (closure);
     }
 }

 void
 g_closure_unref (GClosure *closure)
 {
   guint new_ref_count;

   g_return_if_fail (closure != NULL);
   g_return_if_fail (closure->ref_count > 0);

   if (closure->ref_count == 1)	/* last unref, invalidate first */
     g_closure_invalidate (closure);

   DEC_ASSIGN (closure, ref_count, &new_ref_count);

   if (new_ref_count == 0)
     {
       closure_invoke_notifiers (closure, FNOTIFY);
       g_free (closure->notifiers);
       g_free (closure);
     }
 }

 void
 g_closure_sink (GClosure *closure)
 {
   g_return_if_fail (closure != NULL);
   g_return_if_fail (closure->ref_count > 0);

   /* floating is basically a kludge to avoid creating closures
    * with a ref_count of 0. so the intial ref_count a closure has
    * is unowned. with invoking g_closure_sink() code may
    * indicate that it takes over that intiial ref_count.
    */
   if (closure->floating)
     {
       gboolean was_floating;
       SWAP (closure, floating, FALSE, &was_floating);
       /* unref floating flag only once */
       if (was_floating)
         g_closure_unref (closure);
     }
 }

 void
 g_closure_remove_invalidate_notifier (GClosure      *closure,
 				      gpointer       notify_data,
 				      GClosureNotify notify_func)
 {
   g_return_if_fail (closure != NULL);
   g_return_if_fail (notify_func != NULL);

   if (closure->is_invalid && closure->in_inotify && /* account removal of notify_func() while its called */
       ((gpointer) closure->marshal) == ((gpointer) notify_func) &&
       closure->data == notify_data)
     closure->marshal = NULL;
   else if (!closure_try_remove_inotify (closure, notify_data, notify_func))
     g_warning (G_STRLOC ": unable to remove uninstalled invalidation notifier: %p (%p)",
 	       notify_func, notify_data);
 }

 void
 g_closure_remove_finalize_notifier (GClosure      *closure,
 				    gpointer       notify_data,
 				    GClosureNotify notify_func)
 {
   g_return_if_fail (closure != NULL);
   g_return_if_fail (notify_func != NULL);

   if (closure->is_invalid && !closure->in_inotify && /* account removal of notify_func() while its called */
       ((gpointer) closure->marshal) == ((gpointer) notify_func) &&
       closure->data == notify_data)
     closure->marshal = NULL;
   else if (!closure_try_remove_fnotify (closure, notify_data, notify_func))
     g_warning (G_STRLOC ": unable to remove uninstalled finalization notifier: %p (%p)",
                notify_func, notify_data);
 }

 void
 g_closure_invoke (GClosure       *closure,
 		  GValue /*out*/ *return_value,
 		  guint           n_param_values,
 		  const GValue   *param_values,
 		  gpointer        invocation_hint)
 {
   g_return_if_fail (closure != NULL);

   g_closure_ref (closure);      /* preserve floating flag */
   if (!closure->is_invalid)
     {
       GClosureMarshal marshal;
       gpointer marshal_data;
       gboolean in_marshal = closure->in_marshal;

       g_return_if_fail (closure->marshal || closure->meta_marshal);

       SET (closure, in_marshal, TRUE);
       if (closure->meta_marshal)
 	{
 	  marshal_data = closure->notifiers[0].data;
 	  marshal = (GClosureMarshal) closure->notifiers[0].notify;
 	}
       else
 	{
 	  marshal_data = NULL;
 	  marshal = closure->marshal;
 	}
       if (!in_marshal)
 	closure_invoke_notifiers (closure, PRE_NOTIFY);
       marshal (closure,
 	       return_value,
 	       n_param_values, param_values,
 	       invocation_hint,
 	       marshal_data);
       if (!in_marshal)
 	closure_invoke_notifiers (closure, POST_NOTIFY);
       SET (closure, in_marshal, in_marshal);
     }
   g_closure_unref (closure);
 }

 void
 g_closure_set_marshal (GClosure       *closure,
 		       GClosureMarshal marshal)
 {
   g_return_if_fail (closure != NULL);
   g_return_if_fail (marshal != NULL);

   if (closure->marshal && closure->marshal != marshal)
     g_warning ("attempt to override closure->marshal (%p) with new marshal (%p)",
 	       closure->marshal, marshal);
   else
     closure->marshal = marshal;
 }

 GClosure*
 g_cclosure_new (GCallback      callback_func,
 		gpointer       user_data,
 		GClosureNotify destroy_data)
 {
   GClosure *closure;

   g_return_val_if_fail (callback_func != NULL, NULL);

   closure = g_closure_new_simple (sizeof (GCClosure), user_data);
   if (destroy_data)
     g_closure_add_finalize_notifier (closure, user_data, destroy_data);
   ((GCClosure*) closure)->callback = (gpointer) callback_func;

   return closure;
 }

 GClosure*
 g_cclosure_new_swap (GCallback      callback_func,
 		     gpointer       user_data,
 		     GClosureNotify destroy_data)
 {
   GClosure *closure;

   g_return_val_if_fail (callback_func != NULL, NULL);

   closure = g_closure_new_simple (sizeof (GCClosure), user_data);
   if (destroy_data)
     g_closure_add_finalize_notifier (closure, user_data, destroy_data);
   ((GCClosure*) closure)->callback = (gpointer) callback_func;
   SET (closure, derivative_flag, TRUE);

   return closure;
 }

 static void
 g_type_class_meta_marshal (GClosure       *closure,
 			   GValue /*out*/ *return_value,
 			   guint           n_param_values,
 			   const GValue   *param_values,
 			   gpointer        invocation_hint,
 			   gpointer        marshal_data)
 {
   GTypeClass *class;
   gpointer callback;
   /* GType itype = (GType) closure->data; */
   guint offset = GPOINTER_TO_UINT (marshal_data);

   class = G_TYPE_INSTANCE_GET_CLASS (g_value_peek_pointer (param_values + 0), itype, GTypeClass);
   callback = G_STRUCT_MEMBER (gpointer, class, offset);
   if (callback)
     closure->marshal (closure,
 		      return_value,
 		      n_param_values, param_values,
 		      invocation_hint,
 		      callback);
 }

 static void
 g_type_iface_meta_marshal (GClosure       *closure,
 			   GValue /*out*/ *return_value,
 			   guint           n_param_values,
 			   const GValue   *param_values,
 			   gpointer        invocation_hint,
 			   gpointer        marshal_data)
 {
   GTypeClass *class;
   gpointer callback;
   GType itype = (GType) closure->data;
   guint offset = GPOINTER_TO_UINT (marshal_data);

   class = G_TYPE_INSTANCE_GET_INTERFACE (g_value_peek_pointer (param_values + 0), itype, GTypeClass);
   callback = G_STRUCT_MEMBER (gpointer, class, offset);
   if (callback)
     closure->marshal (closure,
 		      return_value,
 		      n_param_values, param_values,
 		      invocation_hint,
 		      callback);
 }

 GClosure*
 g_signal_type_cclosure_new (GType    itype,
 			    guint    struct_offset)
 {
   GClosure *closure;

   g_return_val_if_fail (G_TYPE_IS_CLASSED (itype) || G_TYPE_IS_INTERFACE (itype), NULL);
   g_return_val_if_fail (struct_offset >= sizeof (GTypeClass), NULL);

   closure = g_closure_new_simple (sizeof (GClosure), (gpointer) itype);
   if (G_TYPE_IS_INTERFACE (itype))
     g_closure_set_meta_marshal (closure, GUINT_TO_POINTER (struct_offset), g_type_iface_meta_marshal);
   else
     g_closure_set_meta_marshal (closure, GUINT_TO_POINTER (struct_offset), g_type_class_meta_marshal);

   return closure;
 }

 #define __G_CLOSURE_C__
 #include "gobjectaliasdef.c"
	/* GObject - GLib Type, Object, Parameter and Signal Library
	* Copyright (C) 2000-2001 Red Hat, Inc.
	* Copyright (C) 2005 Imendio AB
	*
	* This library is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Lesser General Public
	* License as published by the Free Software Foundation; either
	* version 2 of the License, or (at your option) any later version.
	*
	* This library is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Lesser General Public License for more details.
	*
	* You should have received a copy of the GNU Lesser General
	* Public License along with this library; if not, write to the
	* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
	* Boston, MA 02111-1307, USA.
	*/
	#include "gclosure.h"

	/*
	* MT safe with regards to reference counting.
	*/

	#include "gvalue.h"
	#include "gobjectalias.h"
	#include <string.h>


	#define CLOSURE_MAX_REF_COUNT ((1 << 15) - 1)
	#define CLOSURE_MAX_N_GUARDS ((1 << 1) - 1)
	#define CLOSURE_MAX_N_FNOTIFIERS ((1 << 2) - 1)
	#define CLOSURE_MAX_N_INOTIFIERS ((1 << 8) - 1)
	#define CLOSURE_N_MFUNCS(cl) ((cl)->meta_marshal + \
	((cl)->n_guards << 1L))
	/* same as G_CLOSURE_N_NOTIFIERS() (keep in sync) */
	#define CLOSURE_N_NOTIFIERS(cl) (CLOSURE_N_MFUNCS (cl) + \
	(cl)->n_fnotifiers + \
	(cl)->n_inotifiers)

	typedef union {
	GClosure closure;
	volatile gint vint;
	} ClosureInt;

	#define CHANGE_FIELD(_closure, _field, _OP, _value, _must_set, _SET_OLD, _SET_NEW) \
	G_STMT_START { \
	ClosureInt cunion = (ClosureInt) _closure; \
	gint new_int, old_int, success; \
	do \
	{ \
	ClosureInt tmp; \
	tmp.vint = old_int = cunion->vint; \
	_SET_OLD tmp.closure._field; \
	tmp.closure._field _OP _value; \
	_SET_NEW tmp.closure._field; \
	new_int = tmp.vint; \
	success = g_atomic_int_compare_and_exchange (&cunion->vint, old_int, new_int); \
	} \
	while (!success && _must_set); \
	} G_STMT_END

	#define SWAP(_closure, _field, _value, _oldv) CHANGE_FIELD (_closure, _field, =, _value, TRUE, *(_oldv) =, (void) )
	#define SET(_closure, _field, _value) CHANGE_FIELD (_closure, _field, =, _value, TRUE, (void), (void) )
	#define INC(_closure, _field) CHANGE_FIELD (_closure, _field, +=, 1, TRUE, (void), (void) )
	#define INC_ASSIGN(_closure, _field, _newv) CHANGE_FIELD (_closure, _field, +=, 1, TRUE, (void), *(_newv) = )
	#define DEC(_closure, _field) CHANGE_FIELD (_closure, _field, -=, 1, TRUE, (void), (void) )
	#define DEC_ASSIGN(_closure, _field, _newv) CHANGE_FIELD (_closure, _field, -=, 1, TRUE, (void), *(_newv) = )

	#if 0 /* for non-thread-safe closures */
	#define SWAP(cl,f,v,o) (void) (*(o) = cl->f, cl->f = v)
	#define SET(cl,f,v) (void) (cl->f = v)
	#define INC(cl,f) (void) (cl->f += 1)
	#define INC_ASSIGN(cl,f,n) (void) (cl->f += 1, *(n) = cl->f)
	#define DEC(cl,f) (void) (cl->f -= 1)
	#define DEC_ASSIGN(cl,f,n) (void) (cl->f -= 1, *(n) = cl->f)
	#endif

	enum {
	FNOTIFY,
	INOTIFY,
	PRE_NOTIFY,
	POST_NOTIFY
	};


	/* --- functions --- */
	GClosure*
	g_closure_new_simple (guint sizeof_closure,
	gpointer data)
	{
	GClosure *closure;

	g_return_val_if_fail (sizeof_closure >= sizeof (GClosure), NULL);

	closure = g_malloc0 (sizeof_closure);
	SET (closure, ref_count, 1);
	SET (closure, meta_marshal, 0);
	SET (closure, n_guards, 0);
	SET (closure, n_fnotifiers, 0);
	SET (closure, n_inotifiers, 0);
	SET (closure, in_inotify, FALSE);
	SET (closure, floating, TRUE);
	SET (closure, derivative_flag, 0);
	SET (closure, in_marshal, FALSE);
	SET (closure, is_invalid, FALSE);
	closure->marshal = NULL;
	closure->data = data;
	closure->notifiers = NULL;
	memset (G_STRUCT_MEMBER_P (closure, sizeof (closure)), 0, sizeof_closure - sizeof (closure));

	return closure;
	}

	static inline void
	closure_invoke_notifiers (GClosure *closure,
	guint notify_type)
	{
	/* notifier layout:
	* meta_marshal n_guards n_guards n_fnotif. n_inotifiers
	* ->[[meta_marshal][pre_guards][post_guards][fnotifiers][inotifiers]]
	*
	* CLOSURE_N_MFUNCS(cl) = meta_marshal + n_guards + n_guards;
	* CLOSURE_N_NOTIFIERS(cl) = CLOSURE_N_MFUNCS(cl) + n_fnotifiers + n_inotifiers
	*
	* constrains/catches:
	* - closure->notifiers may be reloacted during callback
	* - closure->n_fnotifiers and closure->n_inotifiers may change during callback
	* - i.e. callbacks can be removed/added during invocation
	* - must prepare for callback removal during FNOTIFY and INOTIFY (done via ->marshal= & ->data=)
	* - must distinguish (->marshal= & ->data=) for INOTIFY vs. FNOTIFY (via ->in_inotify)
	* + closure->n_guards is const during PRE_NOTIFY & POST_NOTIFY
	* + closure->meta_marshal is const for all cases
	* + none of the callbacks can cause recursion
	* + closure->n_inotifiers is const 0 during FNOTIFY
	*/
	switch (notify_type)
	{
	GClosureNotifyData *ndata;
	guint i, offs;
	case FNOTIFY:
	while (closure->n_fnotifiers)
	{
	guint n;
	DEC_ASSIGN (closure, n_fnotifiers, &n);

	ndata = closure->notifiers + CLOSURE_N_MFUNCS (closure) + n;
	closure->marshal = (GClosureMarshal) ndata->notify;
	closure->data = ndata->data;
	ndata->notify (ndata->data, closure);
	}
	closure->marshal = NULL;
	closure->data = NULL;
	break;
	case INOTIFY:
	SET (closure, in_inotify, TRUE);
	while (closure->n_inotifiers)
	{
	guint n;
	DEC_ASSIGN (closure, n_inotifiers, &n);

	ndata = closure->notifiers + CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + n;
	closure->marshal = (GClosureMarshal) ndata->notify;
	closure->data = ndata->data;
	ndata->notify (ndata->data, closure);
	}
	closure->marshal = NULL;
	closure->data = NULL;
	SET (closure, in_inotify, FALSE);
	break;
	case PRE_NOTIFY:
	i = closure->n_guards;
	offs = closure->meta_marshal;
	while (i--)
	{
	ndata = closure->notifiers + offs + i;
	ndata->notify (ndata->data, closure);
	}
	break;
	case POST_NOTIFY:
	i = closure->n_guards;
	offs = closure->meta_marshal + i;
	while (i--)
	{
	ndata = closure->notifiers + offs + i;
	ndata->notify (ndata->data, closure);
	}
	break;
	}
	}

	void
	g_closure_set_meta_marshal (GClosure *closure,
	gpointer marshal_data,
	GClosureMarshal meta_marshal)
	{
	GClosureNotifyData *notifiers;

	g_return_if_fail (closure != NULL);
	g_return_if_fail (meta_marshal != NULL);
	g_return_if_fail (closure->is_invalid == FALSE);
	g_return_if_fail (closure->in_marshal == FALSE);
	g_return_if_fail (closure->meta_marshal == 0);

	notifiers = closure->notifiers;
	closure->notifiers = g_renew (GClosureNotifyData, NULL, CLOSURE_N_NOTIFIERS (closure) + 1);
	if (notifiers)
	{
	/* usually the meta marshal will be setup right after creation, so the
	* g_memmove() should be rare-case scenario
	*/
	g_memmove (closure->notifiers + 1, notifiers, CLOSURE_N_NOTIFIERS (closure) * sizeof (notifiers[0]));
	g_free (notifiers);
	}
	closure->notifiers[0].data = marshal_data;
	closure->notifiers[0].notify = (GClosureNotify) meta_marshal;
	SET (closure, meta_marshal, 1);
	}

	void
	g_closure_add_marshal_guards (GClosure *closure,
	gpointer pre_marshal_data,
	GClosureNotify pre_marshal_notify,
	gpointer post_marshal_data,
	GClosureNotify post_marshal_notify)
	{
	guint i;

	g_return_if_fail (closure != NULL);
	g_return_if_fail (pre_marshal_notify != NULL);
	g_return_if_fail (post_marshal_notify != NULL);
	g_return_if_fail (closure->is_invalid == FALSE);
	g_return_if_fail (closure->in_marshal == FALSE);
	g_return_if_fail (closure->n_guards < CLOSURE_MAX_N_GUARDS);

	closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 2);
	if (closure->n_inotifiers)
	closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
	closure->n_fnotifiers +
	closure->n_inotifiers + 1)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
	closure->n_fnotifiers + 0)];
	if (closure->n_inotifiers > 1)
	closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
	closure->n_fnotifiers +
	closure->n_inotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
	closure->n_fnotifiers + 1)];
	if (closure->n_fnotifiers)
	closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
	closure->n_fnotifiers + 1)] = closure->notifiers[CLOSURE_N_MFUNCS (closure) + 0];
	if (closure->n_fnotifiers > 1)
	closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
	closure->n_fnotifiers)] = closure->notifiers[CLOSURE_N_MFUNCS (closure) + 1];
	if (closure->n_guards)
	closure->notifiers[(closure->meta_marshal +
	closure->n_guards +
	closure->n_guards + 1)] = closure->notifiers[closure->meta_marshal + closure->n_guards];
	i = closure->n_guards;
	closure->notifiers[closure->meta_marshal + i].data = pre_marshal_data;
	closure->notifiers[closure->meta_marshal + i].notify = pre_marshal_notify;
	closure->notifiers[closure->meta_marshal + i + 1].data = post_marshal_data;
	closure->notifiers[closure->meta_marshal + i + 1].notify = post_marshal_notify;
	INC (closure, n_guards);
	}

	void
	g_closure_add_finalize_notifier (GClosure *closure,
	gpointer notify_data,
	GClosureNotify notify_func)
	{
	guint i;

	g_return_if_fail (closure != NULL);
	g_return_if_fail (notify_func != NULL);
	g_return_if_fail (closure->n_fnotifiers < CLOSURE_MAX_N_FNOTIFIERS);

	closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 1);
	if (closure->n_inotifiers)
	closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
	closure->n_fnotifiers +
	closure->n_inotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
	closure->n_fnotifiers + 0)];
	i = CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers;
	closure->notifiers[i].data = notify_data;
	closure->notifiers[i].notify = notify_func;
	INC (closure, n_fnotifiers);
	}

	void
	g_closure_add_invalidate_notifier (GClosure *closure,
	gpointer notify_data,
	GClosureNotify notify_func)
	{
	guint i;

	g_return_if_fail (closure != NULL);
	g_return_if_fail (notify_func != NULL);
	g_return_if_fail (closure->is_invalid == FALSE);
	g_return_if_fail (closure->n_inotifiers < CLOSURE_MAX_N_INOTIFIERS);

	closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 1);
	i = CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + closure->n_inotifiers;
	closure->notifiers[i].data = notify_data;
	closure->notifiers[i].notify = notify_func;
	INC (closure, n_inotifiers);
	}

	static inline gboolean
	closure_try_remove_inotify (GClosure *closure,
	gpointer notify_data,
	GClosureNotify notify_func)
	{
	GClosureNotifyData ndata, nlast;

	nlast = closure->notifiers + CLOSURE_N_NOTIFIERS (closure) - 1;
	for (ndata = nlast + 1 - closure->n_inotifiers; ndata <= nlast; ndata++)
	if (ndata->notify == notify_func && ndata->data == notify_data)
	{
	DEC (closure, n_inotifiers);
	if (ndata < nlast)
	ndata = nlast;

	return TRUE;
	}
	return FALSE;
	}

	static inline gboolean
	closure_try_remove_fnotify (GClosure *closure,
	gpointer notify_data,
	GClosureNotify notify_func)
	{
	GClosureNotifyData ndata, nlast;

	nlast = closure->notifiers + CLOSURE_N_NOTIFIERS (closure) - closure->n_inotifiers - 1;
	for (ndata = nlast + 1 - closure->n_fnotifiers; ndata <= nlast; ndata++)
	if (ndata->notify == notify_func && ndata->data == notify_data)
	{
	DEC (closure, n_fnotifiers);
	if (ndata < nlast)
	ndata = nlast;
	if (closure->n_inotifiers)
	closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
	closure->n_fnotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
	closure->n_fnotifiers +
	closure->n_inotifiers)];
	return TRUE;
	}
	return FALSE;
	}

	GClosure*
	g_closure_ref (GClosure *closure)
	{
	guint new_ref_count;
	g_return_val_if_fail (closure != NULL, NULL);
	g_return_val_if_fail (closure->ref_count > 0, NULL);
	g_return_val_if_fail (closure->ref_count < CLOSURE_MAX_REF_COUNT, NULL);

	INC_ASSIGN (closure, ref_count, &new_ref_count);
	g_return_val_if_fail (new_ref_count > 1, NULL);

	return closure;
	}

	void
	g_closure_invalidate (GClosure *closure)
	{
	g_return_if_fail (closure != NULL);

	if (!closure->is_invalid)
	{
	gboolean was_invalid;
	g_closure_ref (closure); /* preserve floating flag */
	SWAP (closure, is_invalid, TRUE, &was_invalid);
	/* invalidate only once */
	if (!was_invalid)
	closure_invoke_notifiers (closure, INOTIFY);
	g_closure_unref (closure);
	}
	}

	void
	g_closure_unref (GClosure *closure)
	{
	guint new_ref_count;

	g_return_if_fail (closure != NULL);
	g_return_if_fail (closure->ref_count > 0);

	if (closure->ref_count == 1) /* last unref, invalidate first */
	g_closure_invalidate (closure);

	DEC_ASSIGN (closure, ref_count, &new_ref_count);

	if (new_ref_count == 0)
	{
	closure_invoke_notifiers (closure, FNOTIFY);
	g_free (closure->notifiers);
	g_free (closure);
	}
	}

	void
	g_closure_sink (GClosure *closure)
	{
	g_return_if_fail (closure != NULL);
	g_return_if_fail (closure->ref_count > 0);

	/* floating is basically a kludge to avoid creating closures
	* with a ref_count of 0. so the intial ref_count a closure has
	* is unowned. with invoking g_closure_sink() code may
	* indicate that it takes over that intiial ref_count.
	*/
	if (closure->floating)
	{
	gboolean was_floating;
	SWAP (closure, floating, FALSE, &was_floating);
	/* unref floating flag only once */
	if (was_floating)
	g_closure_unref (closure);
	}
	}

	void
	g_closure_remove_invalidate_notifier (GClosure *closure,
	gpointer notify_data,
	GClosureNotify notify_func)
	{
	g_return_if_fail (closure != NULL);
	g_return_if_fail (notify_func != NULL);

	if (closure->is_invalid && closure->in_inotify && /* account removal of notify_func() while its called */
	((gpointer) closure->marshal) == ((gpointer) notify_func) &&
	closure->data == notify_data)
	closure->marshal = NULL;
	else if (!closure_try_remove_inotify (closure, notify_data, notify_func))
	g_warning (G_STRLOC ": unable to remove uninstalled invalidation notifier: %p (%p)",
	notify_func, notify_data);
	}

	void
	g_closure_remove_finalize_notifier (GClosure *closure,
	gpointer notify_data,
	GClosureNotify notify_func)
	{
	g_return_if_fail (closure != NULL);
	g_return_if_fail (notify_func != NULL);

	if (closure->is_invalid && !closure->in_inotify && /* account removal of notify_func() while its called */
	((gpointer) closure->marshal) == ((gpointer) notify_func) &&
	closure->data == notify_data)
	closure->marshal = NULL;
	else if (!closure_try_remove_fnotify (closure, notify_data, notify_func))
	g_warning (G_STRLOC ": unable to remove uninstalled finalization notifier: %p (%p)",
	notify_func, notify_data);
	}

	void
	g_closure_invoke (GClosure *closure,
	GValue /out/ *return_value,
	guint n_param_values,
	const GValue *param_values,
	gpointer invocation_hint)
	{
	g_return_if_fail (closure != NULL);

	g_closure_ref (closure); /* preserve floating flag */
	if (!closure->is_invalid)
	{
	GClosureMarshal marshal;
	gpointer marshal_data;
	gboolean in_marshal = closure->in_marshal;

	g_return_if_fail (closure->marshal \|\| closure->meta_marshal);

	SET (closure, in_marshal, TRUE);
	if (closure->meta_marshal)
	{
	marshal_data = closure->notifiers[0].data;
	marshal = (GClosureMarshal) closure->notifiers[0].notify;
	}
	else
	{
	marshal_data = NULL;
	marshal = closure->marshal;
	}
	if (!in_marshal)
	closure_invoke_notifiers (closure, PRE_NOTIFY);
	marshal (closure,
	return_value,
	n_param_values, param_values,
	invocation_hint,
	marshal_data);
	if (!in_marshal)
	closure_invoke_notifiers (closure, POST_NOTIFY);
	SET (closure, in_marshal, in_marshal);
	}
	g_closure_unref (closure);
	}

	void
	g_closure_set_marshal (GClosure *closure,
	GClosureMarshal marshal)
	{
	g_return_if_fail (closure != NULL);
	g_return_if_fail (marshal != NULL);

	if (closure->marshal && closure->marshal != marshal)
	g_warning ("attempt to override closure->marshal (%p) with new marshal (%p)",
	closure->marshal, marshal);
	else
	closure->marshal = marshal;
	}

	GClosure*
	g_cclosure_new (GCallback callback_func,
	gpointer user_data,
	GClosureNotify destroy_data)
	{
	GClosure *closure;

	g_return_val_if_fail (callback_func != NULL, NULL);

	closure = g_closure_new_simple (sizeof (GCClosure), user_data);
	if (destroy_data)
	g_closure_add_finalize_notifier (closure, user_data, destroy_data);
	((GCClosure*) closure)->callback = (gpointer) callback_func;

	return closure;
	}

	GClosure*
	g_cclosure_new_swap (GCallback callback_func,
	gpointer user_data,
	GClosureNotify destroy_data)
	{
	GClosure *closure;

	g_return_val_if_fail (callback_func != NULL, NULL);

	closure = g_closure_new_simple (sizeof (GCClosure), user_data);
	if (destroy_data)
	g_closure_add_finalize_notifier (closure, user_data, destroy_data);
	((GCClosure*) closure)->callback = (gpointer) callback_func;
	SET (closure, derivative_flag, TRUE);

	return closure;
	}

	static void
	g_type_class_meta_marshal (GClosure *closure,
	GValue /out/ *return_value,
	guint n_param_values,
	const GValue *param_values,
	gpointer invocation_hint,
	gpointer marshal_data)
	{
	GTypeClass *class;
	gpointer callback;
	/* GType itype = (GType) closure->data; */
	guint offset = GPOINTER_TO_UINT (marshal_data);

	class = G_TYPE_INSTANCE_GET_CLASS (g_value_peek_pointer (param_values + 0), itype, GTypeClass);
	callback = G_STRUCT_MEMBER (gpointer, class, offset);
	if (callback)
	closure->marshal (closure,
	return_value,
	n_param_values, param_values,
	invocation_hint,
	callback);
	}

	static void
	g_type_iface_meta_marshal (GClosure *closure,
	GValue /out/ *return_value,
	guint n_param_values,
	const GValue *param_values,
	gpointer invocation_hint,
	gpointer marshal_data)
	{
	GTypeClass *class;
	gpointer callback;
	GType itype = (GType) closure->data;
	guint offset = GPOINTER_TO_UINT (marshal_data);

	class = G_TYPE_INSTANCE_GET_INTERFACE (g_value_peek_pointer (param_values + 0), itype, GTypeClass);
	callback = G_STRUCT_MEMBER (gpointer, class, offset);
	if (callback)
	closure->marshal (closure,
	return_value,
	n_param_values, param_values,
	invocation_hint,
	callback);
	}

	GClosure*
	g_signal_type_cclosure_new (GType itype,
	guint struct_offset)
	{
	GClosure *closure;

	g_return_val_if_fail (G_TYPE_IS_CLASSED (itype) \|\| G_TYPE_IS_INTERFACE (itype), NULL);
	g_return_val_if_fail (struct_offset >= sizeof (GTypeClass), NULL);

	closure = g_closure_new_simple (sizeof (GClosure), (gpointer) itype);
	if (G_TYPE_IS_INTERFACE (itype))
	g_closure_set_meta_marshal (closure, GUINT_TO_POINTER (struct_offset), g_type_iface_meta_marshal);
	else
	g_closure_set_meta_marshal (closure, GUINT_TO_POINTER (struct_offset), g_type_class_meta_marshal);

	return closure;
	}

	#define __G_CLOSURE_C__
	#include "gobjectaliasdef.c"