X-Git-Url: https://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2Fsvgtiny.c;h=74ce7eb1775cb92315ac8d7d521ef1533ab2c4a2;hb=aae96e5998971764de34a5e1755a8b27568e5605;hp=2ca5a58664f46077a5ce4358b91f16b28b06eb8c;hpb=751f149981f754a5531ddd1f18a5be4445ae05be;p=libsvgtiny.git

diff --git a/src/svgtiny.c b/src/svgtiny.c
index 2ca5a58..74ce7eb 100644
--- a/src/svgtiny.c
+++ b/src/svgtiny.c
@@ -17,6 +17,8 @@
 #include <dom/dom.h>
 #include <dom/bindings/xml/xmlparser.h>
 
+#include <libcss/libcss.h>
+
 #include "svgtiny.h"
 #include "svgtiny_internal.h"
 
@@ -38,6 +40,12 @@
 #define degToRad(angleInDegrees) ((angleInDegrees) * M_PI / 180.0)
 #define radToDeg(angleInRadians) ((angleInRadians) * 180.0 / M_PI)
 
+static svgtiny_code svgtiny_parse_style_element(dom_element *style,
+		struct svgtiny_parse_state state);
+static css_stylesheet *svgtiny_parse_style_inline(const uint8_t *data,
+		size_t len);
+static svgtiny_code svgtiny_preparse_styles(dom_element *svg,
+		struct svgtiny_parse_state state);
 static svgtiny_code svgtiny_parse_svg(dom_element *svg,
 		struct svgtiny_parse_state state);
 static svgtiny_code svgtiny_parse_path(dom_element *path,
@@ -610,6 +618,7 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
 		const char *buffer, size_t size, const char *url,
 		int viewport_width, int viewport_height)
 {
+	css_error css_code;
 	dom_document *document;
 	dom_exception exc;
 	dom_xml_parser *parser;
@@ -688,13 +697,23 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
 	lwc_string_unref(svg_name_lwc);
 	dom_string_unref(svg_name);
 
-	/* get graphic dimensions */
+	/* initialize the state struct with zeros */
 	memset(&state, 0, sizeof(state));
+
+	/* get graphic dimensions */
 	state.diagram = diagram;
 	state.document = document;
 	state.viewport_width = viewport_width;
 	state.viewport_height = viewport_height;
 
+	/* Initialize CSS context */
+	css_code = css_select_ctx_create(&state.select_ctx);
+	if (css_code != CSS_OK) {
+		dom_node_unref(svg);
+		dom_node_unref(document);
+		return svgtiny_LIBCSS_ERROR;
+	}
+
 #define SVGTINY_STRING_ACTION2(s,n)					\
 	if (dom_string_create_interned((const uint8_t *) #n,		\
 				       strlen(#n), &state.interned_##s)	\
@@ -705,6 +724,19 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
 #include "svgtiny_strings.h"
 #undef SVGTINY_STRING_ACTION2
 
+	/* Intern SVG's xmlns separately because it's an lwc_string
+	 * and not a dom_string. We initialize its pointer to NULL
+	 * because the "cleanup:" test to see if it needs to be free'd
+	 * looks for NULL. Returning a LIBDOM_ERROR on failure is not
+	 * perfect but it's the closest of the available options. */
+	state.interned_svg_xmlns = NULL;
+	if (lwc_intern_string("http://www.w3.org/2000/svg",
+			      26,
+			      &state.interned_svg_xmlns) != lwc_error_ok) {
+		code = svgtiny_LIBDOM_ERROR;
+		goto cleanup;
+	}
+
 	svgtiny_parse_position_attributes(svg, state, &x, &y, &width, &height);
 	diagram->width = width;
 	diagram->height = height;
@@ -723,10 +755,17 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
 	state.stroke_width = 1;
 
 	/* parse tree */
-	code = svgtiny_parse_svg(svg, state);
+	code = svgtiny_preparse_styles(svg, state);
+	if (code == svgtiny_OK) {
+		code = svgtiny_parse_svg(svg, state);
+	}
 
 	dom_node_unref(svg);
 	dom_node_unref(document);
+	css_code = css_select_ctx_destroy(state.select_ctx);
+	if (css_code != CSS_OK) {
+		code = svgtiny_LIBCSS_ERROR;
+	}
 
 cleanup:
 	svgtiny_cleanup_state_local(&state);
@@ -735,10 +774,181 @@ cleanup:
 		dom_string_unref(state.interned_##s);
 #include "svgtiny_strings.h"
 #undef SVGTINY_STRING_ACTION2
+
+	if (state.interned_svg_xmlns != NULL) {
+		lwc_string_unref(state.interned_svg_xmlns);
+	}
+
 	return code;
 }
 
 
+/**
+ * Parse a single <style> element, appending the result to the CSS
+ * select context within the given parser state.
+ */
+svgtiny_code svgtiny_parse_style_element(dom_element *style,
+		struct svgtiny_parse_state state)
+{
+	css_stylesheet *sheet;
+	css_error code;
+	dom_exception exc;
+
+	code = svgtiny_create_stylesheet(&sheet, false);
+	if (code != CSS_OK) {
+		return svgtiny_LIBCSS_ERROR;
+	}
+
+	/* Parse the style element's "media" attribute if it has
+	   one. We don't do anything with it right now. */
+	dom_string *media_attr;
+	exc = dom_element_get_attribute(style, state.interned_media,
+					&media_attr);
+	if (exc != DOM_NO_ERR) {
+		css_stylesheet_destroy(sheet);
+		return svgtiny_LIBDOM_ERROR;
+	}
+
+	if (media_attr) {
+		/* Here's where we'd actually change the media type if
+		   we were going to use it */
+		dom_string_unref(media_attr);
+	}
+
+	dom_string *data;
+	dom_node_get_text_content(style, &data);
+	if (data == NULL) {
+		/* Empty stylesheet? That's fine. */
+		css_stylesheet_destroy(sheet);
+		return svgtiny_OK;
+	}
+
+	code = css_stylesheet_append_data(sheet,
+					  (uint8_t *)dom_string_data(data),
+					  dom_string_byte_length(data));
+	if (code != CSS_OK && code != CSS_NEEDDATA) {
+		dom_string_unref(data);
+		css_stylesheet_destroy(sheet);
+		return svgtiny_LIBCSS_ERROR;
+	}
+
+	code = css_stylesheet_data_done(sheet);
+	if (code != CSS_OK) {
+		dom_string_unref(data);
+		css_stylesheet_destroy(sheet);
+		return svgtiny_LIBCSS_ERROR;
+	}
+
+	code = css_select_ctx_append_sheet(state.select_ctx,
+		sheet,
+		CSS_ORIGIN_AUTHOR,
+		NULL);
+	if (code != CSS_OK) {
+		dom_string_unref(data);
+		return svgtiny_LIBCSS_ERROR;
+	}
+
+	dom_string_unref(data);
+	return svgtiny_OK;
+}
+
+
+/**
+ * Parse the contents of an inline style and return (a pointer to) the
+ * corresponding stylesheet for use with css_select_style(). Returns
+ * NULL if anything goes wrong.
+ */
+css_stylesheet *svgtiny_parse_style_inline(const uint8_t *data,
+		size_t len)
+{
+	css_stylesheet *sheet;
+	css_error code;
+
+	code = svgtiny_create_stylesheet(&sheet, true);
+	if (code != CSS_OK) {
+		return NULL;
+	}
+
+	code = css_stylesheet_append_data(sheet, data, len);
+	if (code != CSS_OK && code != CSS_NEEDDATA) {
+		css_stylesheet_destroy(sheet);
+		return NULL;
+	}
+
+	code = css_stylesheet_data_done(sheet);
+	if (code != CSS_OK) {
+		css_stylesheet_destroy(sheet);
+		return NULL;
+	}
+
+	return sheet;
+}
+
+/**
+ * Parse all <style> elements within a root <svg> element. This
+ * should be called before svgtiny_parse_svg() because that function
+ * makes a single pass through the document and we'd like all style
+ * information to be available during that pass. Specifically, we'd
+ * like a <style> sheet at the end of the document to affect the
+ * rendering of elements at its beginning.
+ *
+ * The element-parsing inner loop here is essentially the same as
+ * that within svgtiny_parse_svg().
+ */
+svgtiny_code svgtiny_preparse_styles(dom_element *svg,
+		struct svgtiny_parse_state state)
+{
+	dom_element *child;
+	dom_exception exc;
+
+	exc = dom_node_get_first_child(svg, (dom_node **) (void *) &child);
+	if (exc != DOM_NO_ERR) {
+		return svgtiny_LIBDOM_ERROR;
+	}
+	while (child != NULL) {
+		dom_element *next;
+		dom_node_type nodetype;
+		svgtiny_code code = svgtiny_OK;
+
+		exc = dom_node_get_node_type(child, &nodetype);
+		if (exc != DOM_NO_ERR) {
+			dom_node_unref(child);
+			return svgtiny_LIBDOM_ERROR;
+		}
+		if (nodetype == DOM_ELEMENT_NODE) {
+			dom_string *nodename;
+			exc = dom_node_get_node_name(child, &nodename);
+			if (exc != DOM_NO_ERR) {
+				dom_node_unref(child);
+				return svgtiny_LIBDOM_ERROR;
+			}
+
+			if (dom_string_caseless_isequal(state.interned_style,
+							nodename)) {
+				/* We have a <style> element, parse it */
+				code = svgtiny_parse_style_element(child,
+								state);
+			}
+
+
+			dom_string_unref(nodename);
+		}
+		if (code != svgtiny_OK) {
+			dom_node_unref(child);
+			return code;
+		}
+		exc = dom_node_get_next_sibling(child,
+						(dom_node **) (void *) &next);
+		dom_node_unref(child);
+		if (exc != DOM_NO_ERR) {
+			return svgtiny_LIBDOM_ERROR;
+		}
+		child = next;
+	}
+
+	return svgtiny_OK;
+}
+
 /**
  * Parse a <svg> or <g> element node.
  */
@@ -1861,6 +2071,22 @@ void svgtiny_parse_paint_attributes(dom_element *node,
 {
 	dom_string *attr;
 	dom_exception exc;
+	css_error code;
+	uint8_t   fill_opacity_type;
+	css_fixed fill_opacity;
+	uint8_t   stroke_opacity_type;
+	css_fixed stroke_opacity;
+
+	/* We store the result of svgtiny_parse_style_inline() in
+	 * inline_sheet, and that function returns NULL on error; in
+	 * particular you do not need to css_stylesheet_destroy() the
+	 * result if it is NULL, and css_stylesheet_destroy() checks
+	 * for that case. */
+	css_stylesheet *inline_sheet = NULL;
+
+	/* Initialize this to NULL for the same reason: so that we can
+	 * safely destroy it later even if we never populated it. */
+	css_select_results *styles = NULL;
 
 	exc = dom_element_get_attribute(node, state->interned_fill, &attr);
 	if (exc == DOM_NO_ERR && attr != NULL) {
@@ -1883,6 +2109,14 @@ void svgtiny_parse_paint_attributes(dom_element *node,
 
 	exc = dom_element_get_attribute(node, state->interned_style, &attr);
 	if (exc == DOM_NO_ERR && attr != NULL) {
+		/* First parse the style attribute into a libcss stylesheet
+		   in case any of its properties are known to libcss. */
+		inline_sheet = svgtiny_parse_style_inline(
+					(uint8_t *)dom_string_data(attr),
+					dom_string_byte_length(attr));
+
+		/* Parse any other properties "by hand" until they can
+		   be supported in libcss. */
 		char *style = strndup(dom_string_data(attr),
 				      dom_string_byte_length(attr));
 		const char *s;
@@ -1915,6 +2149,51 @@ void svgtiny_parse_paint_attributes(dom_element *node,
 		free(style);
 		dom_string_unref(attr);
 	}
+
+	struct dom_element *parent;
+	dom_element_parent_node(node, &parent);
+	if (parent == NULL) {
+		/* This is the root <svg> node, skip it.
+		 *
+		 * While initialising its selection state, libcss sets its
+		 * node_data->bloom pointer using css__get_parent_bloom().
+		 * But if there is no parent, that function returns,
+		 *
+		 *   static css_bloom empty_bloom[CSS_BLOOM_SIZE];
+		 *
+		 * A problem later arises because when libcss FINALISES its
+		 * selection state, it frees node_data->bloom! That obviously
+		 * won't work then node has no parent, i.e. if it's the root
+		 * <svg> element.
+		 */
+		css_stylesheet_destroy(inline_sheet);
+		return;
+	}
+	else {
+		/* We only needed to know if it was NULL */
+		dom_node_unref(parent);
+	}
+
+	code = svgtiny_select_style(state, node, inline_sheet, &styles);
+	css_stylesheet_destroy(inline_sheet);
+	if (code != CSS_OK) {
+		return;
+	}
+
+	fill_opacity_type = css_computed_fill_opacity(
+				styles->styles[CSS_PSEUDO_ELEMENT_NONE],
+				&fill_opacity);
+	stroke_opacity_type = css_computed_stroke_opacity(
+				styles->styles[CSS_PSEUDO_ELEMENT_NONE],
+				&stroke_opacity);
+	css_select_results_destroy(styles);
+
+	if (fill_opacity_type == CSS_FILL_OPACITY_SET) {
+		state->fill_opacity = FIXTOFLT(fill_opacity);
+	}
+	if (stroke_opacity_type == CSS_STROKE_OPACITY_SET) {
+		state->stroke_opacity = FIXTOFLT(stroke_opacity);
+	}
 }
 
 
@@ -2168,6 +2447,8 @@ struct svgtiny_shape *svgtiny_add_shape(struct svgtiny_parse_state *state)
 	shape->text = 0;
 	shape->fill = state->fill;
 	shape->stroke = state->stroke;
+	shape->fill_opacity = state->fill_opacity;
+	shape->stroke_opacity = state->stroke_opacity;
 	shape->stroke_width = lroundf((float) state->stroke_width *
 			(state->ctm.a + state->ctm.d) / 2.0);
 	if (0 < state->stroke_width && shape->stroke_width == 0)