static css_error node_is_root(void *pw, void *node, bool *match);
static css_error node_count_siblings(void *pw, void *node,
bool same_name, bool after, int32_t *count);
+static css_error node_is_empty(void *pw, void *node, bool *is_empty);
+static css_error node_is_link(void *pw, void *node, bool *is_link);
+static css_error node_is_hover(void *pw, void *node, bool *is_hover);
+static css_error node_is_active(void *pw, void *node, bool *is_active);
/**
return CSS_OK;
}
+
+
+/**
+ * Determine whether or not the given element is empty
+ *
+ * An element is "nonempty" if it has a child that is either an
+ * element node or a text node.
+ *
+ * \param pw Pointer to the current SVG parser state
+ * \param node Libdom SVG node to check for emptiness
+ * \param is_empty Pointer to the return value
+ *
+ * \return CSS_OK on success, or CSS_NOMEM if anything goes wrong
+ */
+css_error node_is_empty(void *pw, void *node, bool *is_empty)
+{
+ UNUSED(pw);
+ dom_node *child; /* current child node pointer */
+ dom_node *next; /* next child node pointer */
+ dom_node_type type; /* what type of node is "child" */
+ dom_exception err;
+
+ /* Assume that it's empty by default */
+ *is_empty = true;
+
+ /* Get the given node's first child. Implementation detail:
+ * this increments the reference counter on the child node. */
+ err = dom_node_get_first_child((dom_node *)node, &child);
+ if (err != DOM_NO_ERR) {
+ return CSS_NOMEM;
+ }
+
+ /* And now loop through all children looking for a
+ * text/element node. If we find one, the original
+ * node is "nonempty" */
+ while (child != NULL) {
+ err = dom_node_get_node_type(child, &type);
+ if (err != DOM_NO_ERR) {
+ dom_node_unref(child);
+ return CSS_NOMEM;
+ }
+
+ if (type == DOM_ELEMENT_NODE || type == DOM_TEXT_NODE) {
+ *is_empty = false;
+ dom_node_unref(child);
+ return CSS_OK;
+ }
+
+ err = dom_node_get_next_sibling(child, &next);
+ if (err != DOM_NO_ERR) {
+ dom_node_unref(child);
+ return CSS_NOMEM;
+ }
+
+ /* If we're moving to the next node, we can release
+ * the reference to the current one */
+ dom_node_unref(child);
+ child = next;
+ }
+
+ return CSS_OK;
+}
+
+
+/**
+ * Determine whether or not the given node is a link
+ *
+ * A node is a link if it is an element node whose name is "a" and if
+ * it has an "href" attribute (case-sensitive). This selector
+ * corresponds to node:link pseudo-class in CSS.
+ *
+ * This pseudo-class is a bit awkward because the two standards (HTML5
+ * and CSS) disagree on what it means, and because libsvgtiny does not
+ * have enough information to determine if a link has been "visited"
+ * yet -- that's a UI property. CSS says that :link is for unvisited
+ * links, which we can't determine. HTML5 says that each link must
+ * be either a :link or :visited. Since we can't decide either way,
+ * It seems less wrong to declare that all links are unvisited; i.e.
+ * that they match :link.
+ *
+ * \param pw Pointer to the current SVG parser state
+ * \param node Libdom SVG node to check
+ * \param is_link Pointer to the boolean return value
+ *
+ * \return CSS_OK on success, or CSS_NOMEM if anything goes wrong
+ */
+css_error node_is_link(void *pw, void *node, bool *is_link)
+{
+ dom_exception exc;
+ dom_node *dnode; /* node, but with the right type */
+ dom_string *dnode_name;
+ bool has_href;
+ struct svgtiny_parse_state* state;
+
+ dnode = (dom_node *)node;
+ dnode_name = NULL;
+ has_href = false; /* assume no href attribute */
+ *is_link = false; /* assume that it's not a link */
+
+ exc = dom_node_get_node_name(dnode, &dnode_name);
+ if ((exc != DOM_NO_ERR) || (dnode_name == NULL)) {
+ return CSS_NOMEM;
+ }
+
+ state = (struct svgtiny_parse_state *)pw;
+ if (dom_string_isequal(dnode_name, state->interned_a)) {
+ exc = dom_element_has_attribute(node,
+ state->interned_href,
+ &has_href);
+ if (exc == DOM_NO_ERR && has_href) {
+ *is_link = true;
+ }
+ }
+
+ dom_string_unref(dnode_name);
+ return CSS_OK;
+}
+
+
+/**
+ * Check if the given node is being "hovered" over
+ *
+ * This check always fails because the SVG DOM does not have the
+ * necessary information (it's a UI property).
+ *
+ * \param pw Pointer to the current SVG parser state; unused
+ * \param node Libdom SVG node to check; unused
+ * \param is_hover Pointer to the boolean return value
+ *
+ * \return Always returns CSS_OK
+ */
+css_error node_is_hover(void *pw, void *node, bool *is_hover)
+{
+ UNUSED(pw);
+ UNUSED(node);
+ *is_hover = false;
+ return CSS_OK;
+}
+
+
+/**
+ * Check if the given node is "active"
+ *
+ * This check always fails because the SVG DOM does not have the
+ * necessary information (it's a UI property).
+ *
+ * \param pw Pointer to the current SVG parser state; unused
+ * \param node Libdom SVG node to check; unused
+ * \param is_active Pointer to the boolean return value
+ *
+ * \return Always returns CSS_OK
+ */
+css_error node_is_active(void *pw, void *node, bool *is_active)
+{
+ UNUSED(pw);
+ UNUSED(node);
+ *is_active = false;
+ return CSS_OK;
+}