data.c

 * \returns The strcmp return value.
 */
static int data_search_cmp_string(const struct ast_data_search *root, const char *name,
	char *value)
{
	struct ast_data_search *child;
	enum data_search_comparison cmp_type;
	int ret;

	child = data_search_get_node(root, name);
	if (!child) {
		return 0;
	}

	ret = strcmp(value, child->value);
	cmp_type = child->cmp_type;

	ao2_ref(child, -1);

	return data_search_comparison_result(ret, cmp_type);
}

/*!
 * \internal
 * \brief Based on a search tree, evaluate the specified 'name' inside the tree with the
 *        current pointer address value.
 *        .search = "something=0x32323232"
 *        name = "something"
 *        value is the current value of something and will be evaluated against "0x32323232".
 * \param[in] root The root node pointer of the search tree.
 * \param[in] name The name of the specific.
 * \param[in] ptr The pointer address to compare.
 * \returns The (value - current_value) result.
 */
static int data_search_cmp_ptr(const struct ast_data_search *root, const char *name,
	void *ptr)
{
	struct ast_data_search *child;
	enum data_search_comparison cmp_type;
	void *node_ptr;

	child = data_search_get_node(root, name);
	if (!child) {
		return 0;
	}

	cmp_type = child->cmp_type;

	if (sscanf(child->value, "%p", &node_ptr) <= 0) {
		ao2_ref(child, -1);
		return 1;
	}

	ao2_ref(child, -1);

	return data_search_comparison_result((node_ptr - ptr), cmp_type);
}

/*!
 * \internal
 * \brief Based on a search tree, evaluate the specified 'name' inside the tree with the
 *        current ipv4 address value.
 *        .search = "something=192.168.2.2"
 *        name = "something"
 *        value is the current value of something and will be evaluated against "192.168.2.2".
 * \param[in] root The root node pointer of the search tree.
 * \param[in] name The name of the specific.
 * \param[in] addr The ipv4 address value to compare.
 * \returns The (value - current_value) result.
 */
static int data_search_cmp_ipaddr(const struct ast_data_search *root, const char *name,
	struct in_addr addr)
{
	struct ast_data_search *child;
	enum data_search_comparison cmp_type;
	struct in_addr node_addr;

	child = data_search_get_node(root, name);
	if (!child) {
		return 0;
	}
	cmp_type = child->cmp_type;

	inet_aton(child->value, &node_addr);

	ao2_ref(child, -1);

	return data_search_comparison_result((node_addr.s_addr - addr.s_addr), cmp_type);
}

/*!
 * \internal
 * \brief Based on a search tree, evaluate the specified 'name' inside the tree with the
 *        current boolean value.
 *        .search = "something=true"
 *        name = "something"
 *        value is the current value of something and will be evaluated against "true".
 * \param[in] root The root node pointer of the search tree.
 * \param[in] name The name of the specific.
 * \param[in] value The boolean value to compare.
 * \returns The (value - current_value) result.
 */
static int data_search_cmp_bool(const struct ast_data_search *root, const char *name,
	unsigned int value)
{
	struct ast_data_search *child;
	unsigned int node_value;
	enum data_search_comparison cmp_type;

	child = data_search_get_node(root, name);
	if (!child) {
		return 0;
	}

	node_value = abs(ast_true(child->value));
	cmp_type = child->cmp_type;

	ao2_ref(child, -1);

	return data_search_comparison_result(value - node_value, cmp_type);
}

/*!
 * \internal
 * \brief Based on a search tree, evaluate the specified 'name' inside the tree with the
 *        current double value.
 *        .search = "something=222"
 *        name = "something"
 *        value is the current value of something and will be evaluated against "222".
 * \param[in] root The root node pointer of the search tree.
 * \param[in] name The name of the specific.
 * \param[in] value The double value to compare.
 * \returns The (value - current_value) result.
 */
static int data_search_cmp_dbl(const struct ast_data_search *root, const char *name,
	double value)
{
	struct ast_data_search *child;
	double node_value;
	enum data_search_comparison cmp_type;

	child = data_search_get_node(root, name);
	if (!child) {
		return 0;
	}

	node_value = strtod(child->value, NULL);
	cmp_type = child->cmp_type;

	ao2_ref(child, -1);

	return data_search_comparison_result(value - node_value, cmp_type);
}

/*!
 * \internal
 * \brief Based on a search tree, evaluate the specified 'name' inside the tree with the
 *        current unsigned integer value.
 *        .search = "something=10"
 *        name = "something"
 *        value is the current value of something and will be evaluated against "10".
 * \param[in] root The root node pointer of the search tree.
 * \param[in] name The name of the specific.
 * \param[in] value The unsigned value to compare.
 * \returns The strcmp return value.
 */
static int data_search_cmp_uint(const struct ast_data_search *root, const char *name,
	unsigned int value)
{
	struct ast_data_search *child;
	unsigned int node_value;
	enum data_search_comparison cmp_type;

	child = data_search_get_node(root, name);
	if (!child) {
		return 0;
	}

	node_value = atoi(child->value);
	cmp_type = child->cmp_type;

	ao2_ref(child, -1);

	return data_search_comparison_result(value - node_value, cmp_type);
}

/*!
 * \internal
 * \brief Based on a search tree, evaluate the specified 'name' inside the tree with the
 *        current signed integer value.
 *        .search = "something=10"
 *        name = "something"
 *        value is the current value of something and will be evaluated against "10".
 * \param[in] root The root node pointer of the search tree.
 * \param[in] name The name of the specific.
 * \param[in] value The value to compare.
 * \returns The strcmp return value.
 */
static int data_search_cmp_int(const struct ast_data_search *root, const char *name,
	int value)
{
	struct ast_data_search *child;
	int node_value;
	enum data_search_comparison cmp_type;

	child = data_search_get_node(root, name);
	if (!child) {
		return 0;
	}

	node_value = atoi(child->value);
	cmp_type = child->cmp_type;

	ao2_ref(child, -1);

	return data_search_comparison_result(value - node_value, cmp_type);
}

/*!
 * \internal
 * \brief Based on a search tree, evaluate the specified 'name' inside the tree with the
 *        current character value.
 *        .search = "something=c"
 *        name = "something"
 *        value is the current value of something and will be evaluated against "c".
 * \param[in] root The root node pointer of the search tree.
 * \param[in] name The name of the specific.
 * \param[in] value The boolean value to compare.
 * \returns The (value - current_value) result.
 */
static int data_search_cmp_char(const struct ast_data_search *root, const char *name,
	char value)
{
	struct ast_data_search *child;
	char node_value;
	enum data_search_comparison cmp_type;

	child = data_search_get_node(root, name);
	if (!child) {
		return 0;
	}

	node_value = *(child->value);
	cmp_type = child->cmp_type;

	ao2_ref(child, -1);

	return data_search_comparison_result(value - node_value, cmp_type);
}

/*!
 * \internal
 * \brief Get the member pointer, from a mapping structure, based on its name.
 * \XXX We will need to improve performance here!!.
 * \retval <0 if the member was not found.
 * \retval >=0 The member position in the mapping structure.
 */
static inline int data_search_mapping_find(const struct ast_data_mapping_structure *map,
	size_t mapping_len,
	const char *member_name)
{
	int i;

	for (i = 0; i < mapping_len; i++) {
		if (!strcmp(map[i].name, member_name)) {
			return i;
		}
	}

	return -1;
}

int __ast_data_search_cmp_structure(const struct ast_data_search *search,
	const struct ast_data_mapping_structure *mapping, size_t mapping_len,
	void *structure, const char *structure_name)
{
	struct ao2_iterator i;
	struct ast_data_search *node, *struct_children;
	int member, notmatch = 0;

	if (!search) {
		return 0;
	}

	struct_children = data_search_get_node(search, structure_name);
	if (!struct_children) {
		return 0;
	}

	i = ao2_iterator_init(struct_children->children, 0);
	while ((node = ao2_iterator_next(&i))) {
		member = data_search_mapping_find(mapping, mapping_len, node->name);
		if (member < 0) {
			/* the structure member name doesn't match! */
			ao2_ref(node, -1);
			ao2_ref(struct_children, -1);
			ao2_iterator_destroy(&i);
			return 0;
		}

		notmatch = 0;
		switch (mapping[member].type) {
		case AST_DATA_PASSWORD:
			notmatch = data_search_cmp_string(struct_children,
				node->name,
				mapping[member].get.AST_DATA_PASSWORD(structure));
			break;
		case AST_DATA_TIMESTAMP:
			notmatch = data_search_cmp_uint(struct_children,
				node->name,
				mapping[member].get.AST_DATA_TIMESTAMP(structure));
			break;
		case AST_DATA_SECONDS:
			notmatch = data_search_cmp_uint(struct_children,
				node->name,
				mapping[member].get.AST_DATA_SECONDS(structure));
			break;
		case AST_DATA_MILLISECONDS:
			notmatch = data_search_cmp_uint(struct_children,
				node->name,
				mapping[member].get.AST_DATA_MILLISECONDS(structure));
			break;
		case AST_DATA_STRING:
			notmatch = data_search_cmp_string(struct_children,
				node->name,
				mapping[member].get.AST_DATA_STRING(structure));
			break;
		case AST_DATA_CHARACTER:
			notmatch = data_search_cmp_char(struct_children,
				node->name,
				mapping[member].get.AST_DATA_CHARACTER(structure));
			break;
		case AST_DATA_INTEGER:
			notmatch = data_search_cmp_int(struct_children,
				node->name,
				mapping[member].get.AST_DATA_INTEGER(structure));
			break;
		case AST_DATA_BOOLEAN:
			notmatch = data_search_cmp_bool(struct_children,
				node->name,
				mapping[member].get.AST_DATA_BOOLEAN(structure));
			break;
		case AST_DATA_UNSIGNED_INTEGER:
			notmatch = data_search_cmp_uint(struct_children,
				node->name,
				mapping[member].get.AST_DATA_UNSIGNED_INTEGER(structure));
			break;
		case AST_DATA_DOUBLE:
			notmatch = data_search_cmp_dbl(struct_children,
				node->name,
				mapping[member].get.AST_DATA_DOUBLE(structure));
			break;
		case AST_DATA_IPADDR:
			notmatch = data_search_cmp_ipaddr(struct_children,
				node->name,
				mapping[member].get.AST_DATA_IPADDR(structure));
			break;
		case AST_DATA_POINTER:
			notmatch = data_search_cmp_ptr(struct_children,
				node->name,
				mapping[member].get.AST_DATA_POINTER(structure));
			break;
		case AST_DATA_CONTAINER:
			break;
		}

		ao2_ref(node, -1);
	}
	ao2_iterator_destroy(&i);

	ao2_ref(struct_children, -1);

	return notmatch;
}

/*!
 * \internal
 * \brief Release the memory allocated by a call to ao2_alloc.
 */
static void data_result_destructor(void *obj)
{
	struct ast_data *root = obj;

	switch (root->type) {
	case AST_DATA_PASSWORD:
	case AST_DATA_STRING:
		ast_free(root->payload.str);
		ao2_ref(root->children, -1);
		break;
	case AST_DATA_POINTER:
	case AST_DATA_CHARACTER:
	case AST_DATA_CONTAINER:
	case AST_DATA_INTEGER:
	case AST_DATA_TIMESTAMP:
	case AST_DATA_SECONDS:
	case AST_DATA_MILLISECONDS:
	case AST_DATA_UNSIGNED_INTEGER:
	case AST_DATA_DOUBLE:
	case AST_DATA_BOOLEAN:
	case AST_DATA_IPADDR:
		ao2_ref(root->children, -1);
		break;
	}
}

static struct ast_data *data_result_create(const char *name)
{
	struct ast_data *res;
	size_t namelen;

	namelen = ast_strlen_zero(name) ? 1 : strlen(name) + 1;

	res = ao2_alloc(sizeof(*res) + namelen, data_result_destructor);
	if (!res) {
		return NULL;
	}

	strcpy(res->name, namelen ? name : "");

	/* initialize the children container */
	res->children = ao2_container_alloc(NUM_DATA_RESULT_BUCKETS, data_result_hash,
		data_result_cmp);
	if (!res->children) {
		ao2_ref(res, -1);
		return NULL;
	}

	/* set this node as a container. */
	res->type = AST_DATA_CONTAINER;

	return res;
}

/*!
 * \internal
 * \brief Find a child node, based on its name.
 * \param[in] root The starting point.
 * \param[in] name The child name.
 * \retval NULL if the node wasn't found.
 * \retval non-NULL the node we were looking for.
 */
static struct ast_data *data_result_find_child(struct ast_data *root, const char *name)
{
	struct ast_data *found, *find_node;

	find_node = data_result_create(name);
	if (!find_node) {
		return NULL;
	}

	found = ao2_find(root->children, find_node, OBJ_POINTER);

	/* release the temporary created node used for searching. */
	ao2_ref(find_node, -1);

	return found;
}

int ast_data_search_match(const struct ast_data_search *search, struct ast_data *data)
{
	struct ao2_iterator i, ii;
	struct ast_data_search *s, *s_child;
	struct ast_data *d_child;
	int notmatch = 1;

	if (!search) {
		return 1;
	}

	s_child = data_search_find(search->children, data->name);
	if (!s_child) {
		/* nothing to compare */
		ao2_ref(s_child, -1);
		return 1;
	}

	i = ao2_iterator_init(s_child->children, 0);
	while ((s = ao2_iterator_next(&i))) {
		if (!ao2_container_count(s->children)) {
			/* compare this search node with every data node */
			d_child = data_result_find_child(data, s->name);
			if (!d_child) {
				ao2_ref(s, -1);
				notmatch = 1;
				continue;
			}

			switch (d_child->type) {
			case AST_DATA_PASSWORD:
			case AST_DATA_STRING:
				notmatch = data_search_cmp_string(s_child, d_child->name,
					d_child->payload.str);
				break;
			case AST_DATA_CHARACTER:
				notmatch = data_search_cmp_char(s_child, d_child->name,
					d_child->payload.character);
				break;
			case AST_DATA_INTEGER:
				notmatch = data_search_cmp_int(s_child, d_child->name,
					d_child->payload.sint);
				break;
			case AST_DATA_BOOLEAN:
				notmatch = data_search_cmp_bool(s_child, d_child->name,
					d_child->payload.boolean);
				break;
			case AST_DATA_UNSIGNED_INTEGER:
				notmatch = data_search_cmp_uint(s_child, d_child->name,
					d_child->payload.uint);
				break;
			case AST_DATA_TIMESTAMP:
			case AST_DATA_SECONDS:
			case AST_DATA_MILLISECONDS:
			case AST_DATA_DOUBLE:
				notmatch = data_search_cmp_uint(s_child, d_child->name,
					d_child->payload.dbl);
				break;
			case AST_DATA_IPADDR:
				notmatch = data_search_cmp_ipaddr(s_child, d_child->name,
					d_child->payload.ipaddr);
				break;
			case AST_DATA_POINTER:
				notmatch = data_search_cmp_ptr(s_child, d_child->name,
					d_child->payload.ptr);
				break;
			case AST_DATA_CONTAINER:
				break;
			}
			ao2_ref(d_child, -1);
		} else {
			ii = ao2_iterator_init(data->children, 0);
			while ((d_child = ao2_iterator_next(&ii))) {
				if (strcmp(d_child->name, s->name)) {
					ao2_ref(d_child, -1);
					continue;
				}
				if (!(notmatch = !ast_data_search_match(s_child, d_child))) {
					/* do not continue if we have a match. */
					ao2_ref(d_child, -1);
					break;
				}
				ao2_ref(d_child, -1);
			}
			ao2_iterator_destroy(&ii);
		}
		ao2_ref(s, -1);
		if (notmatch) {
			/* do not continue if we don't have a match. */
			break;
		}
	}
	ao2_iterator_destroy(&i);

	ao2_ref(s_child, -1);

	return !notmatch;
}

/*!
 * \internal
 * \brief Get an internal node, from the result set.
 * \param[in] node A node container.
 * \param[in] path The path to the needed internal node.
 * \retval NULL if the internal node is not found.
 * \retval non-NULL the internal node with path 'path'.
 */
static struct ast_data *data_result_get_node(struct ast_data *node,
	const char *path)
{
	char *savepath, *node_name;
	struct ast_data *child, *current = node;

	savepath = ast_strdupa(path);
	node_name = next_node_name(&savepath);

	while (node_name) {
		child = data_result_find_child(current, node_name);
		if (current != node) {
			ao2_ref(current, -1);
		}
		if (!child) {
			return NULL;
		}
		current = child;
		node_name = next_node_name(&savepath);
	}

	/* do not increment the refcount of the returned object. */
	if (current != node) {
		ao2_ref(current, -1);
	}

	return current;
}

/*!
 * \internal
 * \brief Add a child to the specified root node.
 * \param[in] root The root node pointer.
 * \param[in] child The child to add to the root node.
 */
static void data_result_add_child(struct ast_data *root, struct ast_data *child)
{
	ao2_link(root->children, child);
}

/*!
 * \internal
 * \brief Common string hash function for data nodes
 */
static int data_filter_hash(const void *obj, const int flags)
{
	const struct data_filter *node = obj;
	return ast_str_hash(node->name);
}

/*!
 * \internal
 * \brief Common string comparison function
 */
static int data_filter_cmp(void *obj, void *arg, int flags)
{
	struct data_filter *node1 = obj, *node2 = arg;
	return strcasecmp(node1->name, node2->name) ? 0 : CMP_MATCH;
}

/*!
 * \internal
 * \brief Destroy a data filter tree.
 * \param[in] obj Data filter list to be destroyed.
 */
static void data_filter_destructor(void *obj)
{
	struct data_filter *filter = obj, *globres;

	while ((globres = AST_LIST_REMOVE_HEAD(&(filter->glob_list), list))) {
		ao2_ref(globres, -1);
	}

	ao2_ref(filter->children, -1);
}

/*!
 * \internal
 * \brief Allocate a filter node.
 * \retval NULL on error.
 * \retval non-NULL The allocated search node structure.
 */
static struct data_filter *data_filter_alloc(const char *name)
{
	char *globname, *token;
	struct data_filter *res, *globfilter;
	size_t name_len = strlen(name) + 1;

	res = ao2_alloc(sizeof(*res) + name_len, data_filter_destructor);
	if (!res) {
		return NULL;
	}

	res->children = ao2_container_alloc(NUM_DATA_FILTER_BUCKETS, data_filter_hash,
		data_filter_cmp);

	if (!res->children) {
		ao2_ref(res, -1);
		return NULL;
	}

	strcpy(res->name, name);

	if (strchr(res->name, '*')) {
		globname = ast_strdupa(res->name);

		while ((token = strsep(&globname, "*"))) {
			globfilter = data_filter_alloc(token);
			AST_LIST_INSERT_TAIL(&(res->glob_list), globfilter, list);
		}
	}

	return res;
}

/*!
 * \internal
 * \brief Release a filter tree.
 * \param[in] filter The filter tree root node.
 */
static void data_filter_release(struct data_filter *filter)
{
	ao2_ref(filter, -1);
}

/*!
 * \internal
 * \brief Find a child node, based on his name.
 * \param[in] parent Where to find the node.
 * \param[in] name The node name to find.
 * \retval NULL if a node wasn't found.
 * \retval The node found.
 * \note Remember to decrement the ref count of the returned node after using it.
 */
static struct data_filter *data_filter_find(struct ao2_container *parent,
	const char *name)
{
	int i, olend, orend, globfound;
	size_t name_len = strlen(name), glob_len;
	struct ao2_iterator iter;
	struct data_filter *find_node, *found, *globres;

	find_node = data_filter_alloc(name);
	if (!find_node) {
		return NULL;
	}

	found = ao2_find(parent, find_node, OBJ_POINTER);

	/* free the created node used for searching. */
	ao2_ref(find_node, -1);

	if (found) {
		return found;
	}

	iter = ao2_iterator_init(parent, 0);
	while ((found = ao2_iterator_next(&iter))) {
		if (!AST_LIST_EMPTY(&(found->glob_list))) {
			i = 0;
			globfound = 1;

			olend = ast_strlen_zero(AST_LIST_FIRST(&(found->glob_list))->name);
			orend = ast_strlen_zero(AST_LIST_LAST(&(found->glob_list))->name);

			AST_LIST_TRAVERSE(&(found->glob_list), globres, list) {
				if (!*globres->name) {
					continue;
				}

				glob_len = strlen(globres->name);

				if (!i && !olend) {
					if (strncasecmp(name, globres->name, glob_len)) {
						globfound = 0;
						break;
					}

					i += glob_len;
					continue;
				}

				for (globfound = 0; name_len - i >= glob_len; ++i) {
					if (!strncasecmp(name + i, globres->name, glob_len)) {
						globfound = 1;
						i += glob_len;
						break;
					}
				}

				if (!globfound) {
					break;
				}
			}

			if (globfound && (i == name_len || orend)) {
				ao2_iterator_destroy(&iter);
				return found;
			}
		}

		ao2_ref(found, -1);
	}
	ao2_iterator_destroy(&iter);

	return NULL;
}

/*!
 * \internal
 * \brief Add a child to the specified node.
 * \param[in] root The root node where to add the child.
 * \param[in] name The name of the node to add.
 * \note Remember to decrement the ref count after using the returned node.
 */
static struct data_filter *data_filter_add_child(struct ao2_container *root,
	char *name)
{
	struct data_filter *node;

	node = data_filter_find(root, name);
	if (node) {
		return node;
	}

	node = data_filter_alloc(name);
	if (!node) {
		return NULL;
	}

	ao2_link(root, node);

	return node;
}

/*!
 * \internal
 * \brief Add a node to a filter list from a path
 * \param[in] Filter list to add the path onto.
 * \param[in] The path to add into the filter list.
 * \retval NULL on error.
 * \retval non-NULL A tree with the wanted nodes.
 */
static int data_filter_add_nodes(struct ao2_container *root, char *path)
{
	struct data_filter *node;
	char *savepath, *saveptr, *token, *node_name;
	int ret = 0;

	if (!path) {
		return 0;
	}

	savepath = ast_strdupa(path);

	node_name = next_node_name(&savepath);

	if (!node_name) {
		return 0;
	}

	for (token = strtok_r(node_name, "|", &saveptr);
			token; token = strtok_r(NULL, "|", &saveptr)) {
		node = data_filter_add_child(root, token);
		if (!node) {
			continue;
		}
		data_filter_add_nodes(node->children, savepath);
		ret = 1;
		ao2_ref(node, -1);
	}

	return ret;
}

/*!
 * \internal
 * \brief Generate a filter list based on a filter string provided by the API user.
 * \param[in] A filter string to create a filter from.
 */
static struct data_filter *data_filter_generate(const char *constfilter)
{
	struct data_filter *filter = NULL;
	char *strfilter, *token, *saveptr;
	int node_added = 0;

	if (!constfilter) {
		return NULL;
	}

	strfilter = ast_strdupa(constfilter);

	filter = data_filter_alloc("/");
	if (!filter) {
		return NULL;
	}

	for (token = strtok_r(strfilter, ",", &saveptr); token;
			token = strtok_r(NULL, ",", &saveptr)) {
		node_added = data_filter_add_nodes(filter->children, token);
	}

	if (!node_added) {
		ao2_ref(filter, -1);
		return NULL;
	}

	return filter;
}

/*!
 * \internal
 * \brief Generate all the tree from a specified provider.
 * \param[in] query The query executed.
 * \param[in] root_provider The provider specified in the path of the query.
 * \param[in] parent_node_name The root node name.
 * \retval NULL on error.
 * \retval non-NULL The generated result tree.
 */
static struct ast_data *data_result_generate_node(const struct ast_data_query *query,
	const struct data_provider *root_provider,
	const char *parent_node_name,
	const struct ast_data_search *search,
	const struct data_filter *filter)
{
	struct ast_data *generated, *node;
	struct ao2_iterator i;
	struct data_provider *provider;
	struct ast_data_search *search_child = NULL;
	struct data_filter *filter_child;

	node = data_result_create(parent_node_name);
	if (!node) {
		ast_log(LOG_ERROR, "Unable to allocate '%s' node\n", parent_node_name);
		return NULL;
	}

	if (root_provider->module) {
		ast_module_ref(root_provider->module);
	}

	/* if this is a terminal node, just run the callback function. */
	if (root_provider->handler && root_provider->handler->get) {
		node->filter = filter;
		root_provider->handler->get(search, node);
		if (root_provider->module) {
			ast_module_unref(root_provider->module);
		}
		return node;
	}

	if (root_provider->module) {
		ast_module_unref(root_provider->module);
	}

	/* if this is not a terminal node, generate every child node. */
	i = ao2_iterator_init(root_provider->children, 0);
	while ((provider = ao2_iterator_next(&i))) {
		filter_child = NULL;
		generated = NULL;

		/* get the internal search node. */
		if (search) {
			search_child = data_search_find(search->children, provider->name);
		}
		/* get the internal filter node. */
		if (filter) {
			filter_child = data_filter_find(filter->children, provider->name);
		}

		if (!filter || filter_child) {
			/* only generate the internal node, if we have something to
			 * generate based on the filtering string. */
			generated = data_result_generate_node(query, provider,
				provider->name,
				search_child, filter_child);
		}

		/* decrement the refcount of the internal search node. */
		if (search_child) {
			ao2_ref(search_child, -1);
		}

		/* decrement the refcount of the internal filter node. */
		if (filter_child) {
			ao2_ref(filter_child, -1);
		}

		if (generated) {
			data_result_add_child(node, generated);
			ao2_ref(generated, -1);
		}

		ao2_ref(provider, -1);
	}
	ao2_iterator_destroy(&i);

	return node;
}

/*!
 * \internal
 * \brief Generate a result tree based on a query.
 * \param[in] query The complete query structure.
 * \param[in] search_path The path to retrieve.
 * \retval NULL on error.
 * \retval non-NULL The generated data result.
 */
static struct ast_data *data_result_generate(const struct ast_data_query *query,
	const char *search_path)
{
	char *node_name, *tmp_path;
	struct data_provider *provider_child, *tmp_provider_child;
	struct ast_data *result, *result_filtered;
	struct ast_data_search *search = NULL, *search_child = NULL;
	struct data_filter *filter = NULL, *filter_child = NULL;

	if (!search_path) {
		/* generate all the trees?. */
		return NULL;
	}

	tmp_path = ast_strdupa(search_path);

	/* start searching the root node name */
	node_name = next_node_name(&tmp_path);
	if (!node_name) {
		return NULL;
	}
	provider_child = data_provider_find(root_data.container, node_name, NULL);

	/* continue with the rest of the path. */
	while (provider_child) {
		node_name = next_node_name(&tmp_path);
		if (!node_name) {