API/Node.c

   1 // -*- mode: c++; c-basic-offset: 4 -*-
   2 /*
   3  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  18  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  19  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  20  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  21  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  22  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  24  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #include "Node.h"
  28 #include <stddef.h>
  29 #include <stdlib.h>
  30
  31 Node* Node_new(void)
  32 {
  33     Node* node = (Node*)malloc(sizeof(Node));
  34     node->refCount = 0;
  35     node->nodeType = "Node";
  36     node->childNodesTail = NULL;
  37
  38     return node;
  39 }
  40
  41 void Node_appendChild(Node* node, Node* child)
  42 {
  43     Node_ref(child);
  44     NodeLink* nodeLink = (NodeLink*)malloc(sizeof(NodeLink));
  45     nodeLink->node = child;
  46     nodeLink->prev = node->childNodesTail;
  47     node->childNodesTail = nodeLink;
  48 }
  49
  50 void Node_removeChild(Node* node, Node* child)
  51 {
  52     // Linear search from tail -- good enough for our purposes here
  53     NodeLink* current;
  54     NodeLink** currentHandle;
  55     for (currentHandle = &node->childNodesTail, current = *currentHandle; current; currentHandle = &current->prev, current = *currentHandle) {
  56         if (current->node == child) {
  57             Node_deref(current->node);
  58             *currentHandle = current->prev;
  59             free(current);
  60             break;
  61         }
  62     }
  63 }
  64
  65 void Node_replaceChild(Node* node, Node* newChild, Node* oldChild)
  66 {
  67     // Linear search from tail -- good enough for our purposes here
  68     NodeLink* current;
  69     for (current = node->childNodesTail; current; current = current->prev) {
  70         if (current->node == oldChild) {
  71             Node_deref(current->node);
  72             current->node = newChild;
  73         }
  74     }
  75 }
  76
  77 void Node_ref(Node* node)
  78 {
  79     ++node->refCount;
  80 }
  81
  82 void Node_deref(Node* node)
  83 {
  84     if (--node->refCount == 0)
  85         free(node);
  86 }