static css_error node_name(void *pw, void *node, css_qname *qname);
static css_error node_classes(void *pw, void *node,
lwc_string ***classes, uint32_t *n_classes);
+static css_error node_id(void *pw, void *node, lwc_string **id);
+static css_error named_parent_node(void *pw, void *node,
+ const css_qname *qname, void **parent);
+static css_error named_sibling_node(void *pw, void *node,
+ const css_qname *qname, void **sibling);
+static css_error named_generic_sibling_node(void *pw, void *node,
+ const css_qname *qname, void **sibling);
/**
return CSS_OK;
}
+
+
+/**
+ * Retrieve the given node's id
+ *
+ * \param pw Pointer to the current SVG parser state
+ * \param node Libdom SVG node
+ * \param id Address at which to store the id
+ *
+ * \return CSS_OK on success, or CSS_NOMEM if anything goes wrong
+ */
+css_error node_id(void *pw, void *node, lwc_string **id)
+{
+ dom_string *attr;
+ dom_exception err;
+ struct svgtiny_parse_state *state;
+
+ /* Begin with the assumption that this node has no id */
+ *id = NULL;
+
+ state = (struct svgtiny_parse_state *)pw;
+ err = dom_element_get_attribute((dom_node *)node,
+ state->interned_id, &attr);
+ if (err != DOM_NO_ERR) {
+ return CSS_NOMEM;
+ }
+ else if (attr == NULL) {
+ /* The node has no id attribute and our return value
+ is already set to NULL so we're done */
+ return CSS_OK;
+ }
+
+ /* If we found an id attribute (a dom_string), intern it into
+ an lwc_string that we can return, and then cleanup the
+ dom_string. */
+ err = dom_string_intern(attr, id);
+ if (err != DOM_NO_ERR) {
+ dom_string_unref(attr);
+ return CSS_NOMEM;
+ }
+ dom_string_unref(attr);
+ return CSS_OK;
+}
+
+
+
+/**
+ * Find the first parent of the given element having the given name
+ *
+ * \param pw Pointer to the current SVG parser state
+ * \param node Libdom SVG node
+ * \param qname Name of the parent node to search for
+ * \param parent Address at which to store the parent node pointer
+ *
+ * \return Always returns CSS_OK
+ *
+ * \post If a suitable element is found, a pointer to it will be
+ * stored at the address pointed to by \a parent; otherwise,
+ * NULL will be stored at the address pointed to by \a parent
+ */
+css_error named_parent_node(void *pw, void *node,
+ const css_qname *qname, void **parent)
+{
+ UNUSED(pw);
+ /* dom_element_named_parent_node() was invented to implement
+ * this select handler so there isn't much for us to do except
+ * call it. It's OK if node isn't an element, libdom checks
+ * for it. */
+ dom_element_named_parent_node((dom_element *)node,
+ qname->name,
+ (struct dom_element **)parent);
+
+ /* Implementation detail: dom_element_named_parent_node()
+ * increments the reference count of the parent element before
+ * returning it to us. According to docs/RefCnt in the libdom
+ * repository, this will prevent the parent element from being
+ * destroyed if it is pruned from the DOM. That sounds good,
+ * since we don't want to be using a pointer to an object that
+ * has been destroyed... but we also have no way of later
+ * decrementing the reference count ourselves, and don't want
+ * to make the returned node eternal. Decrementing the
+ * reference counter now allows it to be destroyed when the
+ * DOM no longer needs it, and so long as no other parts of
+ * libsvgtiny are messing with the DOM during parsing, that
+ * shouldn't (ha ha) cause any problems. */
+ dom_node_unref(*parent);
+
+ return CSS_OK;
+}
+
+
+/**
+ * Find the "next-sibling" of the given element having the given name
+ *
+ * This search corresponds to the "+ foo" combinator in CSS and will
+ * find only "foo" element nodes that immediately precede the given
+ * node under the same parent in the DOM. In CSS the tree is viewed
+ * top-down and in libdom it is viewed from the bottom-up; as a result
+ * "next" and "previous" are sometimes backwards. This is case-sensitive.
+ *
+ * \param pw Pointer to the current SVG parser state
+ * \param node Libdom SVG node
+ * \param qname Name of the sibling node to search for
+ * \param sibling Address at which to store the sibling node pointer
+ *
+ * \return Always returns CSS_OK
+ *
+ * \post If a suitable element is found, a pointer to it will be
+ * stored at the address pointed to by \a sibling; otherwise,
+ * NULL will be stored at the address pointed to by \a sibling
+ */
+css_error named_sibling_node(void *pw, void *node,
+ const css_qname *qname, void **sibling)
+{
+ UNUSED(pw);
+ dom_node *n = node; /* the current node */
+ dom_node *prev; /* the previous node */
+ dom_exception err;
+ dom_node_type type;
+ dom_string *name;
+
+ *sibling = NULL; /* default to nothing found */
+
+ /* Begin the search; the first iteration we do outside of the
+ * loop. Implementation detil: dom_node_get_previous_sibling()
+ * increments the reference counter on the returned node. A
+ * comment within named_parent_node() explains why we
+ * decrement it ASAP. */
+ err = dom_node_get_previous_sibling(n, &n);
+ if (err != DOM_NO_ERR) {
+ return CSS_OK;
+ }
+
+ while (n != NULL) {
+ /* We're looking for the first ELEMENT sibling */
+ err = dom_node_get_node_type(n, &type);
+ if (err != DOM_NO_ERR) {
+ dom_node_unref(n);
+ return CSS_OK;
+ }
+
+ if (type == DOM_ELEMENT_NODE) {
+ /* We found an element node, does it have the
+ * right name? */
+ err = dom_node_get_node_name(n, &name);
+ if (err != DOM_NO_ERR) {
+ dom_node_unref(n);
+ return CSS_OK;
+ }
+
+ if (dom_string_lwc_isequal(name,
+ qname->name)) {
+ /* The name is right, return it */
+ *sibling = n;
+ }
+
+ /* There's only one next-sibling element node
+ * and we've already found it, so if its name
+ * wasn't right, we return the default value
+ * of NULL below */
+ dom_string_unref(name);
+ dom_node_unref(n);
+ return CSS_OK;
+ }
+
+ /* Not an element node, so we move on the the previous
+ * previous sibling */
+ err = dom_node_get_previous_sibling(n, &prev);
+ if (err != DOM_NO_ERR) {
+ dom_node_unref(n);
+ return CSS_OK;
+ }
+
+ dom_node_unref(n);
+ n = prev;
+ }
+
+ return CSS_OK;
+}
+
+
+/**
+ * Find the first "subsequent-sibling" of the given element having the
+ * given name
+ *
+ * This search corresponds to the "~ foo" combinator in CSS and will
+ * find only "foo" element nodes that precede the given node (under
+ * the same parent) in the DOM. In CSS the tree is viewed top-down and
+ * in libdom it is viewed from the bottom-up; as a result "next" and
+ * "previous" are sometimes backwards. This is case-sensitive.
+ *
+ * \param pw Pointer to the current SVG parser state
+ * \param node Libdom SVG node
+ * \param qname Name of the sibling node to search for
+ * \param sibling Address at which to store the sibling node pointer
+ *
+ * \return Always returns CSS_OK
+ *
+ * \post If a suitable element is found, a pointer to it will be
+ * stored at the address pointed to by \a sibling; otherwise,
+ * NULL will be stored at the address pointed to by \a sibling
+ */
+css_error named_generic_sibling_node(void *pw, void *node,
+ const css_qname *qname, void **sibling)
+{
+ UNUSED(pw);
+ dom_node *n = node; /* the current node */
+ dom_node *prev; /* the previous node */
+ dom_exception err;
+ dom_node_type type;
+ dom_string *name;
+
+
+ *sibling = NULL; /* default to nothing found */
+
+ /* Begin the search; the first iteration we do outside of the
+ * loop. Implementation detil: dom_node_get_previous_sibling()
+ * increments the reference counter on the returned node. A
+ * comment within named_parent_node() explains why we
+ * decrement it ASAP. */
+ err = dom_node_get_previous_sibling(n, &n);
+ if (err != DOM_NO_ERR) {
+ return CSS_OK;
+ }
+
+ while (n != NULL) {
+ err = dom_node_get_node_type(n, &type);
+ if (err != DOM_NO_ERR) {
+ dom_node_unref(n);
+ return CSS_OK;
+ }
+
+ if (type == DOM_ELEMENT_NODE) {
+ /* We only want ELEMENT nodes */
+ err = dom_node_get_node_name(n, &name);
+ if (err != DOM_NO_ERR) {
+ dom_node_unref(n);
+ return CSS_OK;
+ }
+
+ if (dom_string_lwc_isequal(name,
+ qname->name)) {
+ /* Found one. Save it and stop the search */
+ dom_string_unref(name);
+ dom_node_unref(n);
+ *sibling = n;
+ return CSS_OK;
+ }
+
+ dom_string_unref(name);
+ }
+
+ /* This sibling wasn't an element with the desired
+ name, so move on to the previous sibling */
+ err = dom_node_get_previous_sibling(n, &prev);
+ if (err != DOM_NO_ERR) {
+ dom_node_unref(n);
+ return CSS_OK;
+ }
+
+ dom_node_unref(n);
+ n = prev;
+ }
+
+ return CSS_OK;
+}
projects / libsvgtiny.git / blobdiff