- Preliminary tree code

- added a key enumerator to hashtables (similar to value enumerator,
  just that it enumerates all keys in the hash)

WINGs/tree.c

@@ -0,0 +1,160 @@
+
+
+
+//#include <stdlib.h>
+#include <string.h>
+
+#include "WUtil.h"
+
+
+typedef struct W_TreeNode {
+    void *data;
+
+    //unsigned int uflags:16;
+
+    WMArray *leaves;
+
+    int depth;
+
+    struct W_TreeNode *parent;
+
+    WMFreeDataProc *destructor;
+} W_TreeNode;
+
+
+
+void
+destroyNode(void *data)
+{
+    WMTreeNode *node = (WMTreeNode*) data;
+
+    if (node->destructor) {
+        (*node->destructor)(node->data);
+    }
+    if (node->leaves) {
+        WMFreeArray(node->leaves);
+    }
+    wfree(node);
+}
+
+
+WMTreeNode*
+WMCreateTreeNode(void *data)
+{
+    return WMCreateTreeNodeWithDestructor(data, NULL);
+}
+
+
+WMTreeNode*
+WMCreateTreeNodeWithDestructor(void *data, WMFreeDataProc *destructor)
+{
+    WMTreeNode *node;
+
+    node = (WMTreeNode*) wmalloc(sizeof(W_TreeNode));
+    memset(node, 0, sizeof(W_TreeNode));
+
+    node->destructor = destructor;
+
+    node->data = data;
+    node->parent = NULL;
+    node->depth = 0;
+    node->leaves = WMCreateArrayWithDestructor(1, destroyNode);
+
+    return node;
+}
+
+
+WMTreeNode*
+WMInsertItemInTree(WMTreeNode *parent, int index, void *item)
+{
+    WMTreeNode *node;
+
+    wassertrv(parent!=NULL, NULL);
+
+    node = WMCreateTreeNodeWithDestructor(item, parent->destructor);
+    node->parent = parent;
+    node->depth = parent->depth+1;
+    if (index < 0 || index > WMGetArrayItemCount(parent->leaves)) {
+        WMAddToArray(parent->leaves, node);
+    } else {
+        WMInsertInArray(parent->leaves, index, node);
+    }
+
+    return node;
+}
+
+
+WMTreeNode*
+WMAddItemToTree(WMTreeNode *parent, void *item)
+{
+    WMTreeNode *node;
+
+    wassertrv(parent!=NULL, NULL);
+
+    node = WMCreateTreeNodeWithDestructor(item, parent->destructor);
+    node->parent = parent;
+    node->depth = parent->depth+1;
+    WMAddToArray(parent->leaves, node);
+
+    return node;
+}
+
+
+static void
+updateNodeDepth(WMTreeNode *node, int depth)
+{
+    int i;
+
+    node->depth = depth;
+    for (i=0; i<WMGetArrayItemCount(node->leaves); i++) {
+        updateNodeDepth(WMGetFromArray(node->leaves, i), depth+1);
+    }
+}
+
+
+WMTreeNode*
+WMInsertNodeInTree(WMTreeNode *parent, int index, WMTreeNode *node)
+{
+    wassertrv(parent!=NULL, NULL);
+    wassertrv(node!=NULL, NULL);
+
+    node->parent = parent;
+    updateNodeDepth(node, parent->depth+1);
+    if (index < 0 || index > WMGetArrayItemCount(parent->leaves)) {
+        WMAddToArray(parent->leaves, node);
+    } else {
+        WMInsertInArray(parent->leaves, index, node);
+    }
+
+    return node;
+}
+
+
+WMTreeNode*
+WMAddNodeToTree(WMTreeNode *parent, WMTreeNode *node)
+{
+    wassertrv(parent!=NULL, NULL);
+    wassertrv(node!=NULL, NULL);
+
+    node->parent = parent;
+    updateNodeDepth(node, parent->depth+1);
+    WMAddToArray(parent->leaves, node);
+
+    return node;
+}
+
+
+int
+WMGetTreeNodeDepth(WMTreeNode *node)
+{
+    return node->depth;
+}
+
+
+void
+WMDestroyTreeNode(WMTreeNode *node)
+{
+    destroyNode(node);
+}
+
+