X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2Fsvgtiny_css.c;h=c7faffddef88e447fc1618805cbb450050ff955a;hb=99489346fc8214d7c9473b89361b0c8d17b985db;hp=01b566f93c876ef5f86111b62aa089f614734930;hpb=1c82bd4791dc03bca184c5517f6ff4b5bb592788;p=libsvgtiny.git

diff --git a/src/svgtiny_css.c b/src/svgtiny_css.c
index 01b566f..c7faffd 100644
--- a/src/svgtiny_css.c
+++ b/src/svgtiny_css.c
@@ -9,6 +9,12 @@ static css_error node_classes(void *pw, void *node,
 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);
+static css_error parent_node(void *pw, void *node, void **parent);
+static css_error sibling_node(void *pw, void *node, void **sibling);
 
 
 /**
@@ -228,3 +234,273 @@ css_error named_parent_node(void *pw, void *node,
 
 	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;
+}
+
+
+/**
+ * Return a pointer to the given node's parent
+ *
+ * \param pw      Pointer to the current SVG parser state
+ * \param node    Libdom SVG node
+ * \param parent  Address at which to store the node's parent pointer
+ *
+ * \return Always returns CSS_OK
+ */
+css_error parent_node(void *pw, void *node, void **parent)
+{
+	UNUSED(pw);
+	/* Libdom basically implements this for us */
+	dom_element_parent_node(node, (struct dom_element **)parent);
+
+	/* See the comment in named_parent_node() for why we decrement
+	 * this reference counter here. */
+	dom_node_unref(*parent);
+
+	return CSS_OK;
+}
+
+
+/**
+ * Find the "next-sibling" of the given element
+ *
+ * This search corresponds "+ *" in CSS and will find the first
+ * element node that immediately precedes 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.
+ *
+ * \param pw       Pointer to the current SVG parser state
+ * \param node     Libdom SVG node
+ * \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 sibling_node(void *pw, void *node, void **sibling)
+{
+	UNUSED(pw);
+	dom_node *n = node; /* the current node */
+	dom_node *prev;     /* the previous node */
+	dom_exception err;
+	dom_node_type type;
+
+	*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 found a sibling node that is also an
+			   element and that's all we wanted. */
+			*sibling = n;
+			dom_node_unref(n);
+			return CSS_OK;
+		}
+
+		/* This sibling node was not an element; 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;
+}