1 /*

     2  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.

     3  *

     4  * Redistribution and use in source and binary forms, with or without

     5  * modification, are permitted provided that the following conditions

     6  * are met:

     7  * 1. Redistributions of source code must retain the above copyright

     8  *    notice, this list of conditions and the following disclaimer.

     9  * 2. Redistributions in binary form must reproduce the above copyright

    10  *    notice, this list of conditions and the following disclaimer in the

    11  *    documentation and/or other materials provided with the distribution.

    12  *

    13  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY

    14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

    15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

    16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR

    17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

    18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

    19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

    20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY

    21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

    22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

    23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 

    24  */

    25 

    26 #include "Node.h"

    27 #include <stddef.h>

    28 #include <stdlib.h>

    29 

    30 Node* Node_new(void)

    31 {

    32     Node* node = (Node*)malloc(sizeof(Node));

    33     node->refCount = 0;

    34     node->nodeType = "Node";

    35     node->childNodesTail = NULL;

    36     

    37     return node;

    38 }

    39 

    40 void Node_appendChild(Node* node, Node* child)

    41 {

    42     Node_ref(child);

    43     NodeLink* nodeLink = (NodeLink*)malloc(sizeof(NodeLink));

    44     nodeLink->node = child;

    45     nodeLink->prev = node->childNodesTail;

    46     node->childNodesTail = nodeLink;

    47 }

    48 

    49 void Node_removeChild(Node* node, Node* child)

    50 {

    51     /* Linear search from tail -- good enough for our purposes here */

    52     NodeLink* current;

    53     NodeLink** currentHandle;

    54     for (currentHandle = &node->childNodesTail, current = *currentHandle; current; currentHandle = &current->prev, current = *currentHandle) {

    55         if (current->node == child) {

    56             Node_deref(current->node);

    57             *currentHandle = current->prev;

    58             free(current);

    59             break;

    60         }

    61     }

    62 }

    63 

    64 void Node_replaceChild(Node* node, Node* newChild, Node* oldChild)

    65 {

    66     /* Linear search from tail -- good enough for our purposes here */

    67     NodeLink* current;

    68     for (current = node->childNodesTail; current; current = current->prev) {

    69         if (current->node == oldChild) {

    70             Node_deref(current->node);

    71             current->node = newChild;

    72         }

    73     }

    74 }

    75 

    76 void Node_ref(Node* node)

    77 {

    78     ++node->refCount;

    79 }

    80 

    81 void Node_deref(Node* node)

    82 {

    83     if (--node->refCount == 0)

    84         free(node);

    85 }