+
+
+/**
+ * A "user handler" function that we pass to dom_node_set_user_data()
+ * in set_libcss_node_data(). The set_libcss_node_data() documentation
+ * says that if the node (on which data is set) is is deleted or
+ * cloned, or if its ancestors are modified, then we must call
+ * css_libcss_node_data_handler() on the user data. This function
+ * basically just checks to see which DOM event has happened and
+ * calls css_libcss_node_data_handler() when any of those criteria
+ * are met.
+ */
+static void svgtiny_dom_user_data_handler(dom_node_operation operation,
+ dom_string *key, void *data, struct dom_node *src,
+ struct dom_node *dst)
+{
+ /* We only care about the userdata that is identified by our
+ * userdata key. Unfortunately I see no obvious way to obtain
+ * the copy of the userdata key that is already interned in
+ * svgtiny_strings.h; so we duplicate it here (ugh). */
+ dom_string *str;
+ dom_string_create((const uint8_t *)"_libcss_user_data", 17, &str);
+ if (dom_string_isequal(str,key) == false || data == NULL) {
+ /* Wrong key, or no data */
+ return;
+ }
+
+ /* Check the DOM operation, and make the corresponding call to
+ * css_libcss_node_data_handler(). No error handling is done.
+ */
+ switch (operation) {
+ case DOM_NODE_CLONED:
+ css_libcss_node_data_handler(&svgtiny_select_handler,
+ CSS_NODE_CLONED,
+ NULL, src, dst, data);
+ break;
+ case DOM_NODE_RENAMED:
+ css_libcss_node_data_handler(&svgtiny_select_handler,
+ CSS_NODE_MODIFIED,
+ NULL, src, NULL, data);
+ break;
+ case DOM_NODE_IMPORTED:
+ case DOM_NODE_ADOPTED:
+ case DOM_NODE_DELETED:
+ css_libcss_node_data_handler(&svgtiny_select_handler,
+ CSS_NODE_DELETED,
+ NULL, src, NULL, data);
+ default:
+ /* Our list of cases should have been exhaustive */
+ assert(false);
+ }
+}
+
+/**
+ * Store libcss data on a node
+ *
+ * This is part of the libcss select handler API that we need to
+ * implement. It is essentially a thin dom_node_set_user_data()
+ * wrapper.
+ *
+ * \param pw Pointer to the current SVG parser state
+ * \param node Libdom SVG node on which to store the data
+ * \param libcss_node_data Pointer to the data to store
+ *
+ * \return Always returns CSS_OK
+ */
+css_error set_libcss_node_data(void *pw, void *node,
+ void *libcss_node_data)
+{
+ struct svgtiny_parse_state *state;
+ void *old_data;
+
+ /* A unique "userdata key" (a string) is used to identify this
+ * data. */
+ state = (struct svgtiny_parse_state *)pw;
+ dom_node_set_user_data((dom_node *)node,
+ state->interned_userdata_key,
+ libcss_node_data,
+ svgtiny_dom_user_data_handler,
+ &old_data);
+
+ /* dom_node_set_user_data() always returns DOM_NO_ERR */
+ return CSS_OK;
+}
+
+
+/**
+ * Retrieve libcss data from a node
+ *
+ * This is part of the libcss select handler API that we need to
+ * implement. It is essentially a thin dom_node_get_user_data()
+ * wrapper.
+ *
+ * \param pw Pointer to the current SVG parser state
+ * \param node Libdom SVG node from which to get the data
+ * \param libcss_node_data Address at which to store a pointer to the data
+ *
+ * \return Always returns CSS_OK
+ */
+css_error get_libcss_node_data(void *pw, void *node,
+ void **libcss_node_data)
+{
+ struct svgtiny_parse_state *state;
+
+ /* A unique "userdata key" (a string) is used to identify this
+ * data. */
+ state = (struct svgtiny_parse_state *)pw;
+ dom_node_get_user_data((dom_node *)node,
+ state->interned_userdata_key,
+ libcss_node_data);
+
+ /* dom_node_get_user_data() always returns DOM_NO_ERR */
+ return CSS_OK;
+}
+
+
+/**
+ * The vtable of select handler callbacks passed by libsvgtiny to
+ * css_select_style().
+ */
+static css_select_handler svgtiny_select_handler = {
+ CSS_SELECT_HANDLER_VERSION_1,
+ node_name,
+ node_classes,
+ node_id,
+ named_ancestor_node,
+ named_parent_node,
+ named_sibling_node,
+ named_generic_sibling_node,
+ parent_node,
+ sibling_node,
+ node_has_name,
+ node_has_class,
+ node_has_id,
+ node_has_attribute,
+ node_has_attribute_equal,
+ node_has_attribute_dashmatch,
+ node_has_attribute_includes,
+ node_has_attribute_prefix,
+ node_has_attribute_suffix,
+ node_has_attribute_substring,
+ node_is_root,
+ node_count_siblings,
+ node_is_empty,
+ node_is_link,
+ node_is_visited,
+ node_is_hover,
+ node_is_active,
+ node_is_focus,
+ node_is_enabled,
+ node_is_disabled,
+ node_is_checked,
+ node_is_target,
+ node_is_lang,
+ node_presentational_hint,
+ ua_default_for_property,
+ set_libcss_node_data,
+ get_libcss_node_data,
+};
+
+