gtype.c

嵌入式下基于MiniGUI的Web Browser

      
      do
	{
	  guint i;
	  IFaceEntry *check;
	  
	  i = (n_ifaces + 1) >> 1;
	  check = ifaces + i;
	  if (iface_type == check->iface_type)
	    return check;
	  else if (iface_type > check->iface_type)
	    {
	      n_ifaces -= i;
	      ifaces = check;
	    }
	  else /* if (iface_type < check->iface_type) */
	    n_ifaces = i - 1;
	}
      while (n_ifaces);
    }
  
  return NULL;
}

static inline gboolean
type_lookup_prerequisite_L (TypeNode *iface,
			    GType     prerequisite_type)
{
  if (NODE_IS_IFACE (iface) && IFACE_NODE_N_PREREQUISITES (iface))
    {
      GType *prerequisites = IFACE_NODE_PREREQUISITES (iface) - 1;
      guint n_prerequisites = IFACE_NODE_N_PREREQUISITES (iface);
      
      do
	{
	  guint i;
	  GType *check;
	  
	  i = (n_prerequisites + 1) >> 1;
	  check = prerequisites + i;
	  if (prerequisite_type == *check)
	    return TRUE;
	  else if (prerequisite_type > *check)
	    {
	      n_prerequisites -= i;
	      prerequisites = check;
	    }
	  else /* if (prerequisite_type < *check) */
	    n_prerequisites = i - 1;
	}
      while (n_prerequisites);
    }
  return FALSE;
}

static gchar*
type_descriptive_name_I (GType type)
{
  if (type)
    {
      TypeNode *node = lookup_type_node_I (type);
      
      return node ? NODE_NAME (node) : "<unknown>";
    }
  else
    return "<invalid>";
}


/* --- type consistency checks --- */
static gboolean
check_plugin_U (GTypePlugin *plugin,
		gboolean     need_complete_type_info,
		gboolean     need_complete_interface_info,
		const gchar *type_name)
{
  /* G_IS_TYPE_PLUGIN() and G_TYPE_PLUGIN_GET_CLASS() are external calls: _U 
   */
  if (!plugin)
    {
      g_warning ("plugin handle for type `%s' is NULL",
		 type_name);
      return FALSE;
    }
  if (!G_IS_TYPE_PLUGIN (plugin))
    {
      g_warning ("plugin pointer (%p) for type `%s' is invalid",
		 plugin, type_name);
      return FALSE;
    }
  if (need_complete_type_info && !G_TYPE_PLUGIN_GET_CLASS (plugin)->complete_type_info)
    {
      g_warning ("plugin for type `%s' has no complete_type_info() implementation",
		 type_name);
      return FALSE;
    }
  if (need_complete_interface_info && !G_TYPE_PLUGIN_GET_CLASS (plugin)->complete_interface_info)
    {
      g_warning ("plugin for type `%s' has no complete_interface_info() implementation",
		 type_name);
      return FALSE;
    }
  return TRUE;
}

static gboolean
check_type_name_I (const gchar *type_name)
{
  static const gchar *extra_chars = "-_+";
  const gchar *p = type_name;
  gboolean name_valid;
  
  if (!type_name[0] || !type_name[1] || !type_name[2])
    {
      g_warning ("type name `%s' is too short", type_name);
      return FALSE;
    }
  /* check the first letter */
  name_valid = (p[0] >= 'A' && p[0] <= 'Z') || (p[0] >= 'a' && p[0] <= 'z') || p[0] == '_';
  for (p = type_name + 1; *p; p++)
    name_valid &= ((p[0] >= 'A' && p[0] <= 'Z') ||
		   (p[0] >= 'a' && p[0] <= 'z') ||
		   (p[0] >= '0' && p[0] <= '9') ||
		   strchr (extra_chars, p[0]));
  if (!name_valid)
    {
      g_warning ("type name `%s' contains invalid characters", type_name);
      return FALSE;
    }
  if (g_type_from_name (type_name))
    {
      g_warning ("cannot register existing type `%s'", type_name);
      return FALSE;
    }
  
  return TRUE;
}

static gboolean
check_derivation_I (GType        parent_type,
		    const gchar *type_name)
{
  TypeNode *pnode;
  GTypeFundamentalInfo* finfo;
  
  pnode = lookup_type_node_I (parent_type);
  if (!pnode)
    {
      g_warning ("cannot derive type `%s' from invalid parent type `%s'",
		 type_name,
		 type_descriptive_name_I (parent_type));
      return FALSE;
    }
  finfo = type_node_fundamental_info_I (pnode);
  /* ensure flat derivability */
  if (!(finfo->type_flags & G_TYPE_FLAG_DERIVABLE))
    {
      g_warning ("cannot derive `%s' from non-derivable parent type `%s'",
		 type_name,
		 NODE_NAME (pnode));
      return FALSE;
    }
  /* ensure deep derivability */
  if (parent_type != NODE_FUNDAMENTAL_TYPE (pnode) &&
      !(finfo->type_flags & G_TYPE_FLAG_DEEP_DERIVABLE))
    {
      g_warning ("cannot derive `%s' from non-fundamental parent type `%s'",
		 type_name,
		 NODE_NAME (pnode));
      return FALSE;
    }
  
  return TRUE;
}

static gboolean
check_collect_format_I (const gchar *collect_format)
{
  const gchar *p = collect_format;
  gchar valid_format[] = { G_VALUE_COLLECT_INT, G_VALUE_COLLECT_LONG,
			   G_VALUE_COLLECT_INT64, G_VALUE_COLLECT_DOUBLE,
			   G_VALUE_COLLECT_POINTER, 0 };
  
  while (*p)
    if (!strchr (valid_format, *p++))
      return FALSE;
  return p - collect_format <= G_VALUE_COLLECT_FORMAT_MAX_LENGTH;
}

static gboolean
check_value_table_I (const gchar           *type_name,
		     const GTypeValueTable *value_table)
{
  if (!value_table)
    return FALSE;
  else if (value_table->value_init == NULL)
    {
      if (value_table->value_free || value_table->value_copy ||
	  value_table->value_peek_pointer ||
	  value_table->collect_format || value_table->collect_value ||
	  value_table->lcopy_format || value_table->lcopy_value)
	g_warning ("cannot handle uninitializable values of type `%s'",
		   type_name);
      return FALSE;
    }
  else /* value_table->value_init != NULL */
    {
      if (!value_table->value_free)
	{
	  /* +++ optional +++
	   * g_warning ("missing `value_free()' for type `%s'", type_name);
	   * return FALSE;
	   */
	}
      if (!value_table->value_copy)
	{
	  g_warning ("missing `value_copy()' for type `%s'", type_name);
	  return FALSE;
	}
      if ((value_table->collect_format || value_table->collect_value) &&
	  (!value_table->collect_format || !value_table->collect_value))
	{
	  g_warning ("one of `collect_format' and `collect_value()' is unspecified for type `%s'",
		     type_name);
	  return FALSE;
	}
      if (value_table->collect_format && !check_collect_format_I (value_table->collect_format))
	{
	  g_warning ("the `%s' specification for type `%s' is too long or invalid",
		     "collect_format",
		     type_name);
	  return FALSE;
	}
      if ((value_table->lcopy_format || value_table->lcopy_value) &&
	  (!value_table->lcopy_format || !value_table->lcopy_value))
	{
	  g_warning ("one of `lcopy_format' and `lcopy_value()' is unspecified for type `%s'",
		     type_name);
	  return FALSE;
	}
      if (value_table->lcopy_format && !check_collect_format_I (value_table->lcopy_format))
	{
	  g_warning ("the `%s' specification for type `%s' is too long or invalid",
		     "lcopy_format",
		     type_name);
	  return FALSE;
	}
    }
  return TRUE;
}

static gboolean
check_type_info_I (TypeNode        *pnode,
		   GType            ftype,
		   const gchar     *type_name,
		   const GTypeInfo *info)
{
  GTypeFundamentalInfo *finfo = type_node_fundamental_info_I (lookup_type_node_I (ftype));
  gboolean is_interface = ftype == G_TYPE_INTERFACE;
  
  g_assert (ftype <= G_TYPE_FUNDAMENTAL_MAX && !(ftype & TYPE_ID_MASK));
  
  /* check instance members */
  if (!(finfo->type_flags & G_TYPE_FLAG_INSTANTIATABLE) &&
      (info->instance_size || info->n_preallocs || info->instance_init))
    {
      if (pnode)
	g_warning ("cannot instantiate `%s', derived from non-instantiatable parent type `%s'",
		   type_name,
		   NODE_NAME (pnode));
      else
	g_warning ("cannot instantiate `%s' as non-instantiatable fundamental",
		   type_name);
      return FALSE;
    }
  /* check class & interface members */
  if (!(finfo->type_flags & G_TYPE_FLAG_CLASSED) &&
      (info->class_init || info->class_finalize || info->class_data ||
       (!is_interface && (info->class_size || info->base_init || info->base_finalize))))
    {
      if (pnode)
	g_warning ("cannot create class for `%s', derived from non-classed parent type `%s'",
		   type_name,
                   NODE_NAME (pnode));
      else
	g_warning ("cannot create class for `%s' as non-classed fundamental",
		   type_name);
      return FALSE;
    }
  /* check interface size */
  if (is_interface && info->class_size < sizeof (GTypeInterface))
    {
      g_warning ("specified interface size for type `%s' is smaller than `GTypeInterface' size",
		 type_name);
      return FALSE;
    }
  /* check class size */
  if (finfo->type_flags & G_TYPE_FLAG_CLASSED)
    {
      if (info->class_size < sizeof (GTypeClass))
	{
	  g_warning ("specified class size for type `%s' is smaller than `GTypeClass' size",
		     type_name);
	  return FALSE;
	}
      if (pnode && info->class_size < pnode->data->class.class_size)
	{
	  g_warning ("specified class size for type `%s' is smaller "
		     "than the parent type's `%s' class size",
		     type_name,
		     NODE_NAME (pnode));
	  return FALSE;
	}
    }
  /* check instance size */
  if (finfo->type_flags & G_TYPE_FLAG_INSTANTIATABLE)
    {
      if (info->instance_size < sizeof (GTypeInstance))
	{
	  g_warning ("specified instance size for type `%s' is smaller than `GTypeInstance' size",
		     type_name);
	  return FALSE;
	}
      if (pnode && info->instance_size < pnode->data->instance.instance_size)
	{
	  g_warning ("specified instance size for type `%s' is smaller "
		     "than the parent type's `%s' instance size",
		     type_name,
		     NODE_NAME (pnode));
	  return FALSE;
	}
    }
  
  return TRUE;
}

static TypeNode*
find_conforming_child_type_L (TypeNode *pnode,
			      TypeNode *iface)
{
  TypeNode *node = NULL;
  guint i;
  
  if (type_lookup_iface_entry_L (pnode, iface))
    return pnode;
  
  for (i = 0; i < pnode->n_children && !node; i++)
    node = find_conforming_child_type_L (lookup_type_node_I (pnode->children[i]), iface);
  
  return node;
}

static gboolean
check_add_interface_L (GType instance_type,
		       GType iface_type)
{
  TypeNode *node = lookup_type_node_I (instance_type);
  TypeNode *iface = lookup_type_node_I (iface_type);
  IFaceEntry *entry;
  TypeNode *tnode;
  GType *prerequisites;
  guint i;

  
  if (!node || !node->is_instantiatable)
    {
      g_warning ("cannot add interfaces to invalid (non-instantiatable) type `%s'",
		 type_descriptive_name_I (instance_type));
      return FALSE;
    }
  if (!iface || !NODE_IS_IFACE (iface))
    {
      g_warning ("cannot add invalid (non-interface) type `%s' to type `%s'",
		 type_descriptive_name_I (iface_type),
		 NODE_NAME (node));
      return FALSE;
    }
  tnode = lookup_type_node_I (NODE_PARENT_TYPE (iface));
  if (NODE_PARENT_TYPE (tnode) && !type_lookup_iface_entry_L (node, tnode))
    {
      /* 2001/7/31:timj: erk, i guess this warning is junk as interface derivation is flat */
      g_warning ("cannot add sub-interface `%s' to type `%s' which does not conform to super-interface `%s'",
		 NODE_NAME (iface),
		 NODE_NAME (node),
		 NODE_NAME (tnode));
      return FALSE;
    }
  /* allow overriding of interface type introduced for parent type */
  entry = type_lookup_iface_entry_L (node, iface);
  if (entry && entry->vtable == NULL && !type_iface_peek_holder_L (iface, NODE_TYPE (node)))
    {
      /* ok, we do conform to this interface already, but the interface vtable was not
       * yet intialized, and we just conform to the interface because it got added to
       * one of our parents. so we allow overriding of holder info here.
       */
      return TRUE;
    }
  /* check whether one of our children already conforms (or whether the interface
   * got added to this node already)
   */
  tnode = find_conforming_child_type_L (node, iface);  /* tnode is_a node */
  if (tnode)
    {
      g_warning ("cannot add interface type `%s' to type `%s', since type `%s' already conforms to interface",
		 NODE_NAME (iface),
		 NODE_NAME (node),
		 NODE_NAME (tnode));
      return FALSE;
    }
  prerequisites = IFACE_NODE_PREREQUISITES (iface);
  for (i = 0; i < IFACE_NODE_N_PREREQUISITES (iface); i++)
    {
      tnode = lookup_type_node_I (prerequisites[i]);
      if (!type_node_is_a_L (node, tnode))
	{
	  g_warning ("cannot add interface type `%s' to type `%s' which does not conform to prerequisite `%s'",
		     NODE_NAME (iface),
		     NODE_NAME (node),
		     NODE_NAME (tnode));
	  return FALSE;
	}