src/svgtiny_css.c: implement node_presentational_hint() select handler

[libsvgtiny.git] / src / svgtiny_css.c

diff --git a/src/svgtiny_css.c b/src/svgtiny_css.c
index 4e42888d59c83925d8ce3fa77eb30cb277525cdd..f01c3b40df17ca066611aec5a3458c8d6d104bd2 100644 (file)
--- a/src/svgtiny_css.c
+++ b/src/svgtiny_css.c
@@ -57,8 +57,14 @@ static css_error node_is_checked(void *pw, void *node, bool *is_checked);
 static css_error node_is_target(void *pw, void *node, bool *is_target);
 static css_error node_is_lang(void *pw, void *node,
                lwc_string *lang, bool *is_lang);
+static css_error node_presentational_hint(void *pw, void *node,
+               uint32_t *nhints, css_hint **hints);
 static css_error ua_default_for_property(void *pw, uint32_t property,
        css_hint *hint);
+static css_error set_libcss_node_data(void *pw, void *node,
+               void *libcss_node_data);
+static css_error get_libcss_node_data(void *pw, void *node,
+               void **libcss_node_data);
 
 
 /**
@@ -1767,6 +1773,31 @@ static css_error node_is_lang(void *pw, void *node,
 }
 
 
+/**
+ * Return presentational hints for the given node
+ *
+ * Unless an SVG is being rendered from within an HTML document,
+ * there are no presentational hints. We always return an empty
+ * array (no hints).
+ *
+ * \param pw        Pointer to the current SVG parser state; unused
+ * \param node      Libdom SVG node whose hints we want; unused
+ * \param nhints    How many hints are returned (return by reference)
+ * \param hints     Array of css_hint structures (return by reference)
+ *
+ * \return Always returns CSS_OK
+ */
+css_error node_presentational_hint(void *pw, void *node,
+               uint32_t *nhints, css_hint **hints)
+{
+       UNUSED(pw);
+       UNUSED(node);
+       *nhints = 0;
+       *hints = NULL;
+       return CSS_OK;
+}
+
+
 /**
  * User-agent defaults for CSS properties
  *
@@ -1787,3 +1818,69 @@ css_error ua_default_for_property(void *pw, uint32_t property,
        UNUSED(hint);
        return CSS_INVALID;
 }
+
+
+/**
+ * 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. The fourth parameter (NULL) is a "user handler
+        * function." We will eventually have one, but for now we set
+        * it to NULL to avoid a circular reference mess that would
+        * break the build temporarily. */
+       state = (struct svgtiny_parse_state *)pw;
+       dom_node_set_user_data((dom_node *)node,
+                               state->interned_userdata_key,
+                               libcss_node_data,
+                               NULL,
+                               &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;
+}