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diff --git a/src/libmowgli/mowgli_dictionary.c b/src/libmowgli/mowgli_dictionary.c
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+/*
+ * libmowgli: A collection of useful routines for programming.
+ * mowgli_dictionary.c: Dictionary-based information storage.
+ *
+ * Copyright (c) 2007 William Pitcock <nenolod -at- sacredspiral.co.uk>
+ * Copyright (c) 2007 Jilles Tjoelker <jilles -at- stack.nl>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice is present in all copies.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "mowgli.h"
+
+static mowgli_heap_t *elem_heap = NULL;
+
+struct mowgli_dictionary_
+{
+ mowgli_dictionary_comparator_func_t compare_cb;
+ mowgli_dictionary_elem_t *root, *head, *tail;
+ unsigned int count;
+ char *id;
+ mowgli_boolean_t dirty;
+};
+
+static void warn_deprecated (void)
+{
+ static char warned = 0;
+ if (warned)
+ return;
+
+ printf("mowgli_dictionary is deprecated and pending removal in Mowgli 1.0 "
+ "series.\nPlease use mowgli_patricia instead.\n");
+ warned = 1;
+}
+
+/*
+ * mowgli_dictionary_create(mowgli_dictionary_comparator_func_t compare_cb)
+ *
+ * Dictionary object factory.
+ *
+ * Inputs:
+ * - function to use for comparing two entries in the dtree
+ *
+ * Outputs:
+ * - on success, a new dictionary object.
+ *
+ * Side Effects:
+ * - if services runs out of memory and cannot allocate the object,
+ * the program will abort.
+ */
+mowgli_dictionary_t *mowgli_dictionary_create(mowgli_dictionary_comparator_func_t compare_cb)
+{
+ mowgli_dictionary_t *dtree = (mowgli_dictionary_t *) mowgli_alloc(sizeof(mowgli_dictionary_t));
+
+ dtree->compare_cb = compare_cb;
+
+ if (!elem_heap)
+ elem_heap = mowgli_heap_create(sizeof(mowgli_dictionary_elem_t), 1024, BH_NOW);
+
+ warn_deprecated();
+ return dtree;
+}
+
+/*
+ * mowgli_dictionary_create_named(const char *name,
+ * mowgli_dictionary_comparator_func_t compare_cb)
+ *
+ * Dictionary object factory.
+ *
+ * Inputs:
+ * - dictionary name
+ * - function to use for comparing two entries in the dtree
+ *
+ * Outputs:
+ * - on success, a new dictionary object.
+ *
+ * Side Effects:
+ * - if services runs out of memory and cannot allocate the object,
+ * the program will abort.
+ */
+mowgli_dictionary_t *mowgli_dictionary_create_named(const char *name,
+ mowgli_dictionary_comparator_func_t compare_cb)
+{
+ mowgli_dictionary_t *dtree = (mowgli_dictionary_t *) mowgli_alloc(sizeof(mowgli_dictionary_t));
+
+ dtree->compare_cb = compare_cb;
+ dtree->id = strdup(name);
+
+ if (!elem_heap)
+ elem_heap = mowgli_heap_create(sizeof(mowgli_dictionary_elem_t), 1024, BH_NOW);
+
+ warn_deprecated();
+ return dtree;
+}
+
+/*
+ * mowgli_dictionary_set_comparator_func(mowgli_dictionary_t *dict,
+ * mowgli_dictionary_comparator_func_t compare_cb)
+ *
+ * Resets the comparator function used by the dictionary code for
+ * updating the DTree structure.
+ *
+ * Inputs:
+ * - dictionary object
+ * - new comparator function (passed as functor)
+ *
+ * Outputs:
+ * - nothing
+ *
+ * Side Effects:
+ * - the dictionary comparator function is reset.
+ */
+void mowgli_dictionary_set_comparator_func(mowgli_dictionary_t *dict,
+ mowgli_dictionary_comparator_func_t compare_cb)
+{
+ return_if_fail(dict != NULL);
+ return_if_fail(compare_cb != NULL);
+
+ dict->compare_cb = compare_cb;
+}
+
+/*
+ * mowgli_dictionary_get_comparator_func(mowgli_dictionary_t *dict)
+ *
+ * Returns the current comparator function used by the dictionary.
+ *
+ * Inputs:
+ * - dictionary object
+ *
+ * Outputs:
+ * - comparator function (returned as functor)
+ *
+ * Side Effects:
+ * - none
+ */
+mowgli_dictionary_comparator_func_t
+mowgli_dictionary_get_comparator_func(mowgli_dictionary_t *dict)
+{
+ return_val_if_fail(dict != NULL, NULL);
+
+ return dict->compare_cb;
+}
+
+/*
+ * mowgli_dictionary_get_linear_index(mowgli_dictionary_t *dict,
+ * const char *key)
+ *
+ * Gets a linear index number for key.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - pointer to data
+ *
+ * Outputs:
+ * - position, from zero.
+ *
+ * Side Effects:
+ * - rebuilds the linear index if the tree is marked as dirty.
+ */
+int
+mowgli_dictionary_get_linear_index(mowgli_dictionary_t *dict, const char *key)
+{
+ mowgli_dictionary_elem_t *elem;
+
+ return_val_if_fail(dict != NULL, 0);
+ return_val_if_fail(key != NULL, 0);
+
+ elem = mowgli_dictionary_find(dict, key);
+ if (elem == NULL)
+ return -1;
+
+ if (!dict->dirty)
+ return elem->position;
+ else
+ {
+ mowgli_dictionary_elem_t *delem;
+ int i;
+
+ for (delem = dict->head, i = 0; delem != NULL; delem = delem->next, i++)
+ delem->position = i;
+
+ dict->dirty = FALSE;
+ }
+
+ return elem->position;
+}
+
+/*
+ * mowgli_dictionary_retune(mowgli_dictionary_t *dict, const char *key)
+ *
+ * Retunes the tree, self-optimizing for the element which belongs to key.
+ *
+ * Tuning the tree structure is a very complex operation. Unlike
+ * 2-3-4 trees and BTree/BTree+ structures, this structure is a
+ * constantly evolving algorithm.
+ *
+ * Instead of maintaining a balanced tree, we constantly adapt the
+ * tree by nominating a new root nearby the most recently looked up
+ * or added data. We are constantly retuning ourselves instead of
+ * doing massive O(n) rebalance operations as seen in BTrees,
+ * and the level of data stored in a tree is dynamic, instead of being
+ * held to a restricted design like other trees.
+ *
+ * Moreover, we are different than a radix/patricia tree, because we
+ * don't statically allocate positions. Radix trees have the advantage
+ * of not requiring tuning or balancing operations while having the
+ * disadvantage of requiring a large amount of memory to store
+ * large trees. Our efficiency as far as speed goes is not as
+ * fast as a radix tree; but is close to it.
+ *
+ * The retuning algorithm uses the comparison callback that is
+ * passed in the initialization of the tree container. If the
+ * comparator returns a value which is less than zero, we push the
+ * losing node out of the way, causing it to later be reparented
+ * with another node. The winning child of this comparison is always
+ * the right-most node.
+ *
+ * Once we have reached the key which has been targeted, or have reached
+ * a deadend, we nominate the nearest node as the new root of the tree.
+ * If an exact match has been found, the new root becomes the node which
+ * represents key.
+ *
+ * This results in a tree which can self-optimize for both critical
+ * conditions: nodes which are distant and similar and trees which
+ * have ordered lookups.
+ *
+ * Inputs:
+ * - node to begin search from
+ *
+ * Outputs:
+ * - none
+ *
+ * Side Effects:
+ * - a new root node is nominated.
+ */
+void
+mowgli_dictionary_retune(mowgli_dictionary_t *dict, const char *key)
+{
+ mowgli_dictionary_elem_t n, *tn, *left, *right, *node;
+ int ret;
+
+ return_if_fail(dict != NULL);
+
+ if (dict->root == NULL)
+ return;
+
+ /*
+ * we initialize n with known values, since it's on stack
+ * memory. otherwise the dict would become corrupted.
+ *
+ * n is used for temporary storage while the tree is retuned.
+ * -nenolod
+ */
+ n.left = n.right = NULL;
+ left = right = &n;
+
+ /* this for(;;) loop is the main workhorse of the rebalancing */
+ for (node = dict->root; ; )
+ {
+ if ((ret = dict->compare_cb(key, node->key)) == 0)
+ break;
+
+ if (ret < 0)
+ {
+ if (node->left == NULL)
+ break;
+
+ if ((ret = dict->compare_cb(key, node->left->key)) < 0)
+ {
+ tn = node->left;
+ node->left = tn->right;
+ tn->right = node;
+ node = tn;
+
+ if (node->left == NULL)
+ break;
+ }
+
+ right->left = node;
+ right = node;
+ node = node->left;
+ }
+ else
+ {
+ if (node->right == NULL)
+ break;
+
+ if ((ret = dict->compare_cb(key, node->right->key)) > 0)
+ {
+ tn = node->right;
+ node->right = tn->left;
+ tn->left = node;
+ node = tn;
+
+ if (node->right == NULL)
+ break;
+ }
+
+ left->right = node;
+ left = node;
+ node = node->right;
+ }
+ }
+
+ left->right = node->left;
+ right->left = node->right;
+
+ node->left = n.right;
+ node->right = n.left;
+
+ dict->root = node;
+}
+
+/*
+ * mowgli_dictionary_link(mowgli_dictionary_t *dict,
+ * mowgli_dictionary_elem_t *delem)
+ *
+ * Links a dictionary tree element to the dictionary.
+ *
+ * When we add new nodes to the tree, it becomes the
+ * next nominated root. This is perhaps not a wise
+ * optimization because of automatic retuning, but
+ * it keeps the code simple.
+ *
+ * Inputs:
+ * - dictionary tree
+ * - dictionary tree element
+ *
+ * Outputs:
+ * - nothing
+ *
+ * Side Effects:
+ * - a node is linked to the dictionary tree
+ */
+void
+mowgli_dictionary_link(mowgli_dictionary_t *dict,
+ mowgli_dictionary_elem_t *delem)
+{
+ return_if_fail(dict != NULL);
+ return_if_fail(delem != NULL);
+
+ dict->dirty = TRUE;
+
+ dict->count++;
+
+ if (dict->root == NULL)
+ {
+ delem->left = delem->right = NULL;
+ delem->next = delem->prev = NULL;
+ dict->head = dict->tail = dict->root = delem;
+ }
+ else
+ {
+ int ret;
+
+ mowgli_dictionary_retune(dict, delem->key);
+
+ if ((ret = dict->compare_cb(delem->key, dict->root->key)) < 0)
+ {
+ delem->left = dict->root->left;
+ delem->right = dict->root;
+ dict->root->left = NULL;
+
+ if (dict->root->prev)
+ dict->root->prev->next = delem;
+ else
+ dict->head = delem;
+
+ delem->prev = dict->root->prev;
+ delem->next = dict->root;
+ dict->root->prev = delem;
+ dict->root = delem;
+ }
+ else if (ret > 0)
+ {
+ delem->right = dict->root->right;
+ delem->left = dict->root;
+ dict->root->right = NULL;
+
+ if (dict->root->next)
+ dict->root->next->prev = delem;
+ else
+ dict->tail = delem;
+
+ delem->next = dict->root->next;
+ delem->prev = dict->root;
+ dict->root->next = delem;
+ dict->root = delem;
+ }
+ else
+ {
+ dict->root->key = delem->key;
+ dict->root->data = delem->data;
+ dict->count--;
+
+ mowgli_heap_free(elem_heap, delem);
+ }
+ }
+}
+
+/*
+ * mowgli_dictionary_unlink_root(mowgli_dictionary_t *dict)
+ *
+ * Unlinks the root dictionary tree element from the dictionary.
+ *
+ * Inputs:
+ * - dictionary tree
+ *
+ * Outputs:
+ * - nothing
+ *
+ * Side Effects:
+ * - the root node is unlinked from the dictionary tree
+ */
+void
+mowgli_dictionary_unlink_root(mowgli_dictionary_t *dict)
+{
+ mowgli_dictionary_elem_t *delem, *nextnode, *parentofnext;
+
+ dict->dirty = TRUE;
+
+ delem = dict->root;
+ if (delem == NULL)
+ return;
+
+ if (dict->root->left == NULL)
+ dict->root = dict->root->right;
+ else if (dict->root->right == NULL)
+ dict->root = dict->root->left;
+ else
+ {
+ /* Make the node with the next highest key the new root.
+ * This node has a NULL left pointer. */
+ nextnode = delem->next;
+ soft_assert(nextnode->left == NULL);
+ if (nextnode == delem->right)
+ {
+ dict->root = nextnode;
+ dict->root->left = delem->left;
+ }
+ else
+ {
+ parentofnext = delem->right;
+ while (parentofnext->left != NULL && parentofnext->left != nextnode)
+ parentofnext = parentofnext->left;
+ soft_assert(parentofnext->left == nextnode);
+ parentofnext->left = nextnode->right;
+ dict->root = nextnode;
+ dict->root->left = delem->left;
+ dict->root->right = delem->right;
+ }
+ }
+
+ /* linked list */
+ if (delem->prev != NULL)
+ delem->prev->next = delem->next;
+
+ if (dict->head == delem)
+ dict->head = delem->next;
+
+ if (delem->next)
+ delem->next->prev = delem->prev;
+
+ if (dict->tail == delem)
+ dict->tail = delem->prev;
+
+ dict->count--;
+}
+
+/*
+ * mowgli_dictionary_destroy(mowgli_dictionary_t *dtree,
+ * void (*destroy_cb)(dictionary_elem_t *delem, void *privdata),
+ * void *privdata);
+ *
+ * Recursively destroys all nodes in a dictionary tree.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - optional iteration callback
+ * - optional opaque/private data to pass to callback
+ *
+ * Outputs:
+ * - nothing
+ *
+ * Side Effects:
+ * - on success, a dtree and optionally it's children are destroyed.
+ *
+ * Notes:
+ * - if this is called without a callback, the objects bound to the
+ * DTree will not be destroyed.
+ */
+void mowgli_dictionary_destroy(mowgli_dictionary_t *dtree,
+ void (*destroy_cb)(mowgli_dictionary_elem_t *delem, void *privdata),
+ void *privdata)
+{
+ mowgli_dictionary_elem_t *n, *tn;
+
+ return_if_fail(dtree != NULL);
+
+ MOWGLI_LIST_FOREACH_SAFE(n, tn, dtree->head)
+ {
+ if (destroy_cb != NULL)
+ (*destroy_cb)(n, privdata);
+
+ mowgli_free(n->key);
+ mowgli_heap_free(elem_heap, n);
+ }
+
+ mowgli_free(dtree);
+}
+
+/*
+ * mowgli_dictionary_foreach(mowgli_dictionary_t *dtree,
+ * void (*destroy_cb)(dictionary_elem_t *delem, void *privdata),
+ * void *privdata);
+ *
+ * Iterates over all entries in a DTree.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - optional iteration callback
+ * - optional opaque/private data to pass to callback
+ *
+ * Outputs:
+ * - nothing
+ *
+ * Side Effects:
+ * - on success, a dtree is iterated
+ */
+void mowgli_dictionary_foreach(mowgli_dictionary_t *dtree,
+ int (*foreach_cb)(mowgli_dictionary_elem_t *delem, void *privdata),
+ void *privdata)
+{
+ mowgli_dictionary_elem_t *n, *tn;
+
+ return_if_fail(dtree != NULL);
+
+ MOWGLI_LIST_FOREACH_SAFE(n, tn, dtree->head)
+ {
+ /* delem_t is a subclass of node_t. */
+ mowgli_dictionary_elem_t *delem = (mowgli_dictionary_elem_t *) n;
+
+ if (foreach_cb != NULL)
+ (*foreach_cb)(delem, privdata);
+ }
+}
+
+/*
+ * mowgli_dictionary_search(mowgli_dictionary_t *dtree,
+ * void (*destroy_cb)(mowgli_dictionary_elem_t *delem, void *privdata),
+ * void *privdata);
+ *
+ * Searches all entries in a DTree using a custom callback.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - optional iteration callback
+ * - optional opaque/private data to pass to callback
+ *
+ * Outputs:
+ * - on success, the requested object
+ * - on failure, NULL.
+ *
+ * Side Effects:
+ * - a dtree is iterated until the requested conditions are met
+ */
+void *mowgli_dictionary_search(mowgli_dictionary_t *dtree,
+ void *(*foreach_cb)(mowgli_dictionary_elem_t *delem, void *privdata),
+ void *privdata)
+{
+ mowgli_dictionary_elem_t *n, *tn;
+ void *ret = NULL;
+
+ return_val_if_fail(dtree != NULL, NULL);
+
+ MOWGLI_LIST_FOREACH_SAFE(n, tn, dtree->head)
+ {
+ /* delem_t is a subclass of node_t. */
+ mowgli_dictionary_elem_t *delem = (mowgli_dictionary_elem_t *) n;
+
+ if (foreach_cb != NULL)
+ ret = (*foreach_cb)(delem, privdata);
+
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+/*
+ * mowgli_dictionary_foreach_start(mowgli_dictionary_t *dtree,
+ * mowgli_dictionary_iteration_state_t *state);
+ *
+ * Initializes a static DTree iterator.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - static DTree iterator
+ *
+ * Outputs:
+ * - nothing
+ *
+ * Side Effects:
+ * - the static iterator, &state, is initialized.
+ */
+void mowgli_dictionary_foreach_start(mowgli_dictionary_t *dtree,
+ mowgli_dictionary_iteration_state_t *state)
+{
+ return_if_fail(dtree != NULL);
+ return_if_fail(state != NULL);
+
+ state->cur = NULL;
+ state->next = NULL;
+
+ /* find first item */
+ state->cur = dtree->head;
+
+ if (state->cur == NULL)
+ return;
+
+ /* make state->cur point to first item and state->next point to
+ * second item */
+ state->next = state->cur;
+ mowgli_dictionary_foreach_next(dtree, state);
+}
+
+/*
+ * mowgli_dictionary_foreach_cur(mowgli_dictionary_t *dtree,
+ * mowgli_dictionary_iteration_state_t *state);
+ *
+ * Returns the data from the current node being iterated by the
+ * static iterator.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - static DTree iterator
+ *
+ * Outputs:
+ * - reference to data in the current dtree node being iterated
+ *
+ * Side Effects:
+ * - none
+ */
+void *mowgli_dictionary_foreach_cur(mowgli_dictionary_t *dtree,
+ mowgli_dictionary_iteration_state_t *state)
+{
+ return_val_if_fail(dtree != NULL, NULL);
+ return_val_if_fail(state != NULL, NULL);
+
+ return state->cur != NULL ? state->cur->data : NULL;
+}
+
+/*
+ * mowgli_dictionary_foreach_next(mowgli_dictionary_t *dtree,
+ * mowgli_dictionary_iteration_state_t *state);
+ *
+ * Advances a static DTree iterator.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - static DTree iterator
+ *
+ * Outputs:
+ * - nothing
+ *
+ * Side Effects:
+ * - the static iterator, &state, is advanced to a new DTree node.
+ */
+void mowgli_dictionary_foreach_next(mowgli_dictionary_t *dtree,
+ mowgli_dictionary_iteration_state_t *state)
+{
+ return_if_fail(dtree != NULL);
+ return_if_fail(state != NULL);
+
+ if (state->cur == NULL)
+ {
+ mowgli_log("mowgli_dictionary_foreach_next(): called again after iteration finished on dtree<%p>", dtree);
+ return;
+ }
+
+ state->cur = state->next;
+
+ if (state->next == NULL)
+ return;
+
+ state->next = state->next->next;
+}
+
+/*
+ * mowgli_dictionary_find(mowgli_dictionary_t *dtree, const char *key)
+ *
+ * Looks up a DTree node by name.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - name of node to lookup
+ *
+ * Outputs:
+ * - on success, the dtree node requested
+ * - on failure, NULL
+ *
+ * Side Effects:
+ * - none
+ */
+mowgli_dictionary_elem_t *mowgli_dictionary_find(mowgli_dictionary_t *dict, const char *key)
+{
+ return_val_if_fail(dict != NULL, NULL);
+ return_val_if_fail(key != NULL, NULL);
+
+ /* retune for key, key will be the tree's root if it's available */
+ mowgli_dictionary_retune(dict, key);
+
+ if (dict->root && !dict->compare_cb(key, dict->root->key))
+ return dict->root;
+
+ return NULL;
+}
+
+/*
+ * mowgli_dictionary_add(mowgli_dictionary_t *dtree, const char *key, void *data)
+ *
+ * Creates a new DTree node and binds data to it.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - name for new DTree node
+ * - data to bind to the new DTree node
+ *
+ * Outputs:
+ * - on success, a new DTree node
+ * - on failure, NULL
+ *
+ * Side Effects:
+ * - data is inserted into the DTree.
+ */
+mowgli_dictionary_elem_t *mowgli_dictionary_add(mowgli_dictionary_t *dict, const char *key, void *data)
+{
+ mowgli_dictionary_elem_t *delem;
+
+ return_val_if_fail(dict != NULL, NULL);
+ return_val_if_fail(key != NULL, NULL);
+ return_val_if_fail(data != NULL, NULL);
+ return_val_if_fail(mowgli_dictionary_find(dict, key) == NULL, NULL);
+
+ delem = mowgli_heap_alloc(elem_heap);
+ delem->key = strdup(key);
+ delem->data = data;
+
+ if (delem->key == NULL)
+ {
+ mowgli_log("major WTF: delem->key is NULL, not adding node.", key);
+ mowgli_heap_free(elem_heap, delem);
+ return NULL;
+ }
+
+ mowgli_dictionary_link(dict, delem);
+
+ return delem;
+}
+
+/*
+ * mowgli_dictionary_delete(mowgli_dictionary_t *dtree, const char *key)
+ *
+ * Deletes data from a dictionary tree.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - name of DTree node to delete
+ *
+ * Outputs:
+ * - on success, the remaining data that needs to be mowgli_freed
+ * - on failure, NULL
+ *
+ * Side Effects:
+ * - data is removed from the DTree.
+ *
+ * Notes:
+ * - the returned data needs to be mowgli_freed/released manually!
+ */
+void *mowgli_dictionary_delete(mowgli_dictionary_t *dtree, const char *key)
+{
+ mowgli_dictionary_elem_t *delem = mowgli_dictionary_find(dtree, key);
+ void *data;
+
+ if (delem == NULL)
+ return NULL;
+
+ data = delem->data;
+
+ mowgli_free(delem->key);
+ mowgli_dictionary_unlink_root(dtree);
+ mowgli_heap_free(elem_heap, delem);
+
+ return data;
+}
+
+/*
+ * mowgli_dictionary_retrieve(mowgli_dictionary_t *dtree, const char *key)
+ *
+ * Retrieves data from a dictionary.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - name of node to lookup
+ *
+ * Outputs:
+ * - on success, the data bound to the DTree node.
+ * - on failure, NULL
+ *
+ * Side Effects:
+ * - none
+ */
+void *mowgli_dictionary_retrieve(mowgli_dictionary_t *dtree, const char *key)
+{
+ mowgli_dictionary_elem_t *delem = mowgli_dictionary_find(dtree, key);
+
+ if (delem != NULL)
+ return delem->data;
+
+ return NULL;
+}
+
+/*
+ * mowgli_dictionary_size(mowgli_dictionary_t *dict)
+ *
+ * Returns the size of a dictionary.
+ *
+ * Inputs:
+ * - dictionary tree object
+ *
+ * Outputs:
+ * - size of dictionary
+ *
+ * Side Effects:
+ * - none
+ */
+unsigned int mowgli_dictionary_size(mowgli_dictionary_t *dict)
+{
+ return_val_if_fail(dict != NULL, 0);
+
+ return dict->count;
+}
+
+/* returns the sum of the depths of the subtree rooted in delem at depth depth */
+static int
+stats_recurse(mowgli_dictionary_elem_t *delem, int depth, int *pmaxdepth)
+{
+ int result;
+
+ if (depth > *pmaxdepth)
+ *pmaxdepth = depth;
+ result = depth;
+ if (delem->left)
+ result += stats_recurse(delem->left, depth + 1, pmaxdepth);
+ if (delem->right)
+ result += stats_recurse(delem->right, depth + 1, pmaxdepth);
+ return result;
+}
+
+/*
+ * mowgli_dictionary_stats(mowgli_dictionary_t *dict, void (*cb)(const char *line, void *privdata), void *privdata)
+ *
+ * Returns the size of a dictionary.
+ *
+ * Inputs:
+ * - dictionary tree object
+ * - callback
+ * - data for callback
+ *
+ * Outputs:
+ * - none
+ *
+ * Side Effects:
+ * - callback called with stats text
+ */
+void mowgli_dictionary_stats(mowgli_dictionary_t *dict, void (*cb)(const char *line, void *privdata), void *privdata)
+{
+ char str[256];
+ int sum, maxdepth;
+
+ return_if_fail(dict != NULL);
+
+ if (dict->id != NULL)
+ snprintf(str, sizeof str, "Dictionary stats for %s (%d)",
+ dict->id, dict->count);
+ else
+ snprintf(str, sizeof str, "Dictionary stats for <%p> (%d)",
+ dict, dict->count);
+ cb(str, privdata);
+ maxdepth = 0;
+ if (dict->root != NULL)
+ {
+ sum = stats_recurse(dict->root, 0, &maxdepth);
+ snprintf(str, sizeof str, "Depth sum %d Avg depth %d Max depth %d", sum, sum / dict->count, maxdepth);
+ }
+ else
+ snprintf(str, sizeof str, "Depth sum 0 Avg depth 0 Max depth 0");
+ cb(str, privdata);
+ return;
+}