swfdec/swfdec_as_gcable.c

   1 /* Swfdec
   2  * Copyright (C) 2008 Benjamin Otte <otte@gnome.org>
   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 Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA  02110-1301  USA
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #include "config.h"
  22 #endif
  23
  24 #include "swfdec_as_gcable.h"
  25
  26 #include "swfdec_as_context.h"
  27
  28 gpointer
  29 swfdec_as_gcable_alloc (SwfdecAsContext *context, gsize size)
  30 {
  31   SwfdecAsGcable *mem;
  32   guint8 diff;
  33
  34   g_return_val_if_fail (SWFDEC_IS_AS_CONTEXT (context), NULL);
  35   g_return_val_if_fail (size > sizeof (SwfdecAsGcable), NULL);
  36
  37   swfdec_as_context_use_mem (context, size);
  38   mem = g_slice_alloc0 (size);
  39   if (G_LIKELY ((GPOINTER_TO_SIZE (mem) & SWFDEC_AS_GC_FLAG_MASK) == 0))
  40     return mem;
  41
  42   g_slice_free1 (size, mem);
  43   mem = g_slice_alloc0 (size + SWFDEC_AS_GC_FLAG_MASK);
  44   diff = GPOINTER_TO_SIZE (mem) & SWFDEC_AS_GC_FLAG_MASK;
  45   if (diff == 0)
  46     return mem;
  47
  48   diff = SWFDEC_AS_GC_FLAG_MASK + 1 - diff;
  49   mem += diff;
  50   g_assert ((GPOINTER_TO_SIZE (mem) & SWFDEC_AS_GC_FLAG_MASK) == 0);
  51   SWFDEC_AS_GCABLE_SET_FLAG (mem, SWFDEC_AS_GC_ALIGN);
  52   ((guint8 *) mem)[-1] = diff;
  53
  54   return mem;
  55 }
  56
  57 void
  58 swfdec_as_gcable_free (SwfdecAsContext *context, gpointer mem, gsize size)
  59 {
  60   SwfdecAsGcable *gc;
  61
  62   g_return_if_fail (SWFDEC_IS_AS_CONTEXT (context));
  63   g_return_if_fail (mem != NULL);
  64   g_return_if_fail (size > sizeof (SwfdecAsGcable));
  65
  66   gc = mem;
  67   swfdec_as_context_unuse_mem (context, size);
  68   if (G_UNLIKELY (SWFDEC_AS_GCABLE_FLAG_IS_SET (gc, SWFDEC_AS_GC_ALIGN))) {
  69     mem = ((guint8 *) mem) - ((guint8 *) mem)[-1];
  70     size += SWFDEC_AS_GC_FLAG_MASK;
  71   }
  72   g_slice_free1 (size, mem);
  73 }
  74
  75 SwfdecAsGcable *
  76 swfdec_as_gcable_collect (SwfdecAsContext *context, SwfdecAsGcable *gc,
  77     SwfdecAsGcableDestroyNotify notify)
  78 {
  79   SwfdecAsGcable *prev, *cur, *tmp;
  80
  81   g_return_val_if_fail (SWFDEC_IS_AS_CONTEXT (context), NULL);
  82
  83   prev = NULL;
  84   cur = gc;
  85   for (;;) {
  86     while (cur) {
  87       if (SWFDEC_AS_GCABLE_FLAG_IS_SET (cur, SWFDEC_AS_GC_MARK | SWFDEC_AS_GC_ROOT)) {
  88         if (SWFDEC_AS_GCABLE_FLAG_IS_SET (cur, SWFDEC_AS_GC_MARK))
  89           SWFDEC_AS_GCABLE_UNSET_FLAG (cur, SWFDEC_AS_GC_MARK);
  90         break;
  91       }
  92       tmp = SWFDEC_AS_GCABLE_NEXT (cur);
  93       notify (context, cur);
  94       cur = tmp;
  95     }
  96     if (prev)
  97       SWFDEC_AS_GCABLE_SET_NEXT (prev, cur);
  98     else
  99       gc = cur;
 100     prev = cur;
 101     if (prev == NULL)
 102       break;
 103     cur = SWFDEC_AS_GCABLE_NEXT (cur);
 104   }
 105
 106   return gc;
 107 }
 108