gnode.c

嵌入式下基于MiniGUI的Web Browser

/* GLIB - Library of useful routines for C programming
 * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * GNode: N-way tree implementation.
 * Copyright (C) 1998 Tim Janik
 *
 * 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.
 */

/*
 * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
 * file for a list of people on the GLib Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GLib at ftp://ftp.gtk.org/pub/gtk/. 
 */

/* 
 * MT safe
 */

#ifdef HAVE_CONFIG_H
#include "glibconfig.h"
#endif

#include "glib.h"

#ifndef DISABLE_MEM_POOLS
/* node allocation
 */
struct _GAllocator /* from gmem.c */
{
  gchar         *name;
  guint16        n_preallocs;
  guint          is_unused : 1;
  guint          type : 4;
  GAllocator    *last;
  GMemChunk     *mem_chunk;
  GNode         *free_nodes; /* implementation specific */
};

G_LOCK_DEFINE_STATIC (current_allocator);
static GAllocator *current_allocator = NULL;

/* HOLDS: current_allocator_lock */
static void
g_node_validate_allocator (GAllocator *allocator)
{
  g_return_if_fail (allocator != NULL);
  g_return_if_fail (allocator->is_unused == TRUE);

  if (allocator->type != G_ALLOCATOR_NODE)
    {
      allocator->type = G_ALLOCATOR_NODE;
      if (allocator->mem_chunk)
	{
	  g_mem_chunk_destroy (allocator->mem_chunk);
	  allocator->mem_chunk = NULL;
	}
    }

  if (!allocator->mem_chunk)
    {
      allocator->mem_chunk = g_mem_chunk_new (allocator->name,
					      sizeof (GNode),
					      sizeof (GNode) * allocator->n_preallocs,
					      G_ALLOC_ONLY);
      allocator->free_nodes = NULL;
    }

  allocator->is_unused = FALSE;
}

void
g_node_push_allocator (GAllocator *allocator)
{
  G_LOCK (current_allocator);
  g_node_validate_allocator (allocator);
  allocator->last = current_allocator;
  current_allocator = allocator;
  G_UNLOCK (current_allocator);
}

void
g_node_pop_allocator (void)
{
  G_LOCK (current_allocator);
  if (current_allocator)
    {
      GAllocator *allocator;

      allocator = current_allocator;
      current_allocator = allocator->last;
      allocator->last = NULL;
      allocator->is_unused = TRUE;
    }
  G_UNLOCK (current_allocator);
}


/* --- functions --- */
GNode*
g_node_new (gpointer data)
{
  GNode *node;

  G_LOCK (current_allocator);
  if (!current_allocator)
    {
       GAllocator *allocator = g_allocator_new ("GLib default GNode allocator",
						128);
       g_node_validate_allocator (allocator);
       allocator->last = NULL;
       current_allocator = allocator;
    }
  if (!current_allocator->free_nodes)
    node = g_chunk_new (GNode, current_allocator->mem_chunk);
  else
    {
      node = current_allocator->free_nodes;
      current_allocator->free_nodes = node->next;
    }
  G_UNLOCK (current_allocator);
  
  node->data = data;
  node->next = NULL;
  node->prev = NULL;
  node->parent = NULL;
  node->children = NULL;
  
  return node;
}

static void
g_nodes_free (GNode *node)
{
  GNode *parent;

  parent = node;
  while (1)
    {
      if (parent->children)
	g_nodes_free (parent->children);

#ifdef ENABLE_GC_FRIENDLY
      parent->data = NULL;
      parent->prev = NULL;
      parent->parent = NULL;
      parent->children = NULL;
#endif /* ENABLE_GC_FRIENDLY */

      if (parent->next)
	parent = parent->next;
      else
	break;
    }
  
  G_LOCK (current_allocator);
  parent->next = current_allocator->free_nodes;
  current_allocator->free_nodes = node;
  G_UNLOCK (current_allocator);
}
#else /* DISABLE_MEM_POOLS */

GNode*
g_node_new (gpointer data)
{
  GNode *node;

  node = g_new0 (GNode, 1);
  
  node->data = data;
  
  return node;
}

static void
g_nodes_free (GNode *root)
{
  GNode *node, *next;
  
  node = root;
  while (node != NULL)
    {
      next = node->next;
      g_nodes_free (node->children);
      g_free (node);
      node = next;
    }
}
#endif

void
g_node_destroy (GNode *root)
{
  g_return_if_fail (root != NULL);
  
  if (!G_NODE_IS_ROOT (root))
    g_node_unlink (root);
  
  g_nodes_free (root);
}

void
g_node_unlink (GNode *node)
{
  g_return_if_fail (node != NULL);
  
  if (node->prev)
    node->prev->next = node->next;
  else if (node->parent)
    node->parent->children = node->next;
  node->parent = NULL;
  if (node->next)
    {
      node->next->prev = node->prev;
      node->next = NULL;
    }
  node->prev = NULL;
}

GNode*
g_node_copy (GNode *node)
{
  GNode *new_node = NULL;
  
  if (node)
    {
      GNode *child;
      
      new_node = g_node_new (node->data);
      
      for (child = g_node_last_child (node); child; child = child->prev)
	g_node_prepend (new_node, g_node_copy (child));
    }
  
  return new_node;
}

GNode*
g_node_insert (GNode *parent,
	       gint   position,
	       GNode *node)
{
  g_return_val_if_fail (parent != NULL, node);
  g_return_val_if_fail (node != NULL, node);
  g_return_val_if_fail (G_NODE_IS_ROOT (node), node);
  
  if (position > 0)
    return g_node_insert_before (parent,
				 g_node_nth_child (parent, position),
				 node);
  else if (position == 0)
    return g_node_prepend (parent, node);
  else /* if (position < 0) */
    return g_node_append (parent, node);
}

GNode*
g_node_insert_before (GNode *parent,
		      GNode *sibling,
		      GNode *node)
{
  g_return_val_if_fail (parent != NULL, node);
  g_return_val_if_fail (node != NULL, node);
  g_return_val_if_fail (G_NODE_IS_ROOT (node), node);
  if (sibling)
    g_return_val_if_fail (sibling->parent == parent, node);
  
  node->parent = parent;
  
  if (sibling)
    {
      if (sibling->prev)
	{
	  node->prev = sibling->prev;
	  node->prev->next = node;
	  node->next = sibling;
	  sibling->prev = node;
	}
      else
	{
	  node->parent->children = node;
	  node->next = sibling;
	  sibling->prev = node;
	}
    }
  else
    {
      if (parent->children)
	{
	  sibling = parent->children;
	  while (sibling->next)
	    sibling = sibling->next;
	  node->prev = sibling;
	  sibling->next = node;
	}
      else
	node->parent->children = node;
    }

  return node;
}

GNode*
g_node_insert_after (GNode *parent,
		     GNode *sibling,
		     GNode *node)
{
  g_return_val_if_fail (parent != NULL, node);
  g_return_val_if_fail (node != NULL, node);
  g_return_val_if_fail (G_NODE_IS_ROOT (node), node);
  if (sibling)
    g_return_val_if_fail (sibling->parent == parent, node);

  node->parent = parent;

  if (sibling)
    {
      if (sibling->next)
	{
	  sibling->next->prev = node;
	}
      node->next = sibling->next;
      node->prev = sibling;
      sibling->next = node;
    }
  else
    {
      if (parent->children)
	{
	  node->next = parent->children;
	  parent->children->prev = node;
	}
      parent->children = node;
    }

  return node;
}

GNode*
g_node_prepend (GNode *parent,
		GNode *node)
{
  g_return_val_if_fail (parent != NULL, node);
  
  return g_node_insert_before (parent, parent->children, node);
}

GNode*
g_node_get_root (GNode *node)
{
  g_return_val_if_fail (node != NULL, NULL);
  
  while (node->parent)
    node = node->parent;
  
  return node;
}

gboolean
g_node_is_ancestor (GNode *node,
		    GNode *descendant)
{
  g_return_val_if_fail (node != NULL, FALSE);
  g_return_val_if_fail (descendant != NULL, FALSE);
  
  while (descendant)
    {
      if (descendant->parent == node)
	return TRUE;
      
      descendant = descendant->parent;
    }
  
  return FALSE;
}

/* returns 1 for root, 2 for first level children,
 * 3 for children's children...
 */
guint
g_node_depth (GNode *node)
{
  register guint depth = 0;
  
  while (node)
    {
      depth++;
      node = node->parent;
    }
  
  return depth;
}

void
g_node_reverse_children (GNode *node)
{
  GNode *child;
  GNode *last;
  
  g_return_if_fail (node != NULL);
  
  child = node->children;
  last = NULL;
  while (child)
    {
      last = child;
      child = last->next;
      last->next = last->prev;
      last->prev = child;
    }
  node->children = last;
}

guint
g_node_max_height (GNode *root)
{
  register GNode *child;
  register guint max_height = 0;
  
  if (!root)
    return 0;
  
  child = root->children;
  while (child)
    {
      register guint tmp_height;
      
      tmp_height = g_node_max_height (child);
      if (tmp_height > max_height)
	max_height = tmp_height;
      child = child->next;
    }
  
  return max_height + 1;
}

static gboolean
g_node_traverse_pre_order (GNode	    *node,
			   GTraverseFlags    flags,
			   GNodeTraverseFunc func,
			   gpointer	     data)
{
  if (node->children)
    {
      GNode *child;
      
      if ((flags & G_TRAVERSE_NON_LEAFS) &&
	  func (node, data))
	return TRUE;
      
      child = node->children;
      while (child)
	{
	  register GNode *current;
	  
	  current = child;
	  child = current->next;
	  if (g_node_traverse_pre_order (current, flags, func, data))
	    return TRUE;
	}
    }
  else if ((flags & G_TRAVERSE_LEAFS) &&
	   func (node, data))
    return TRUE;
  
  return FALSE;
}

static gboolean
g_node_depth_traverse_pre_order (GNode		  *node,
				 GTraverseFlags	   flags,
				 guint		   depth,
				 GNodeTraverseFunc func,
				 gpointer	   data)
{
  if (node->children)
    {
      GNode *child;
      
      if ((flags & G_TRAVERSE_NON_LEAFS) &&
	  func (node, data))
	return TRUE;
      
      depth--;
      if (!depth)
	return FALSE;
      
      child = node->children;
      while (child)
	{
	  register GNode *current;
	  
	  current = child;