]> gitweb.michael.orlitzky.com - libsvgtiny.git/blobdiff - src/svgtiny.c
src/svgtiny.c: use case-sensitive comparisons for SVG element names
[libsvgtiny.git] / src / svgtiny.c
index 8cb1eff2f283adf74b00eb42dc6b1bed4078bcd0..98a84d44d7921635a03f67d7188a453a2aaf8ae2 100644 (file)
 #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,
@@ -67,6 +71,8 @@ static void svgtiny_parse_font_attributes(dom_element *node,
                struct svgtiny_parse_state *state);
 static void svgtiny_parse_transform_attributes(dom_element *node,
                struct svgtiny_parse_state *state);
+static css_select_results *svgtiny_parse_styles(dom_element *node,
+               struct svgtiny_parse_state *state);
 static svgtiny_code svgtiny_add_path(float *p, unsigned int n,
                struct svgtiny_parse_state *state);
 static void _svgtiny_parse_color(const char *s, svgtiny_colour *c,
@@ -622,7 +628,22 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
        dom_element *svg;
        dom_string *svg_name;
        lwc_string *svg_name_lwc;
-       struct svgtiny_parse_state state;
+       struct svgtiny_parse_state state = {
+               /* Initialize the unit context here because it has a
+                * const member and doing it any other way subverts
+                * the type system. The magic numbers below were taken
+                * from the libcss example program without much
+                * thought, because at the moment we don't support any
+                * properties with units. */
+               .unit_ctx = {
+                       .font_size_default = FLTTOFIX(16.0),
+                       .font_size_minimum = FLTTOFIX(6.0),
+                       .device_dpi        = FLTTOFIX(96.0),
+                       .root_style        = NULL,
+                       .pw                = NULL,
+                       .measure           = NULL,
+               }
+       };
        float x, y, width, height;
        svgtiny_code code;
 
@@ -682,7 +703,7 @@ svgtiny_code svgtiny_parse(struct svgtiny_diagram *diagram,
                dom_node_unref(document);
                return svgtiny_LIBDOM_ERROR;
        }
-       if (!dom_string_caseless_lwc_isequal(svg_name, svg_name_lwc)) {
+       if (!dom_string_lwc_isequal(svg_name, svg_name_lwc)) {
                lwc_string_unref(svg_name_lwc);
                dom_string_unref(svg_name);
                dom_node_unref(svg);
@@ -693,24 +714,28 @@ 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 */
-       if (state.select_ctx == NULL) {
-               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;
-               }
+       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;
        }
 
+       /* ...and the unit context, whose other fields were
+        * initialized along with the parser state itself */
+       state.unit_ctx.viewport_width    = FLTTOFIX(viewport_width);
+       state.unit_ctx.viewport_height   = FLTTOFIX(viewport_height);
+
 #define SVGTINY_STRING_ACTION2(s,n)                                    \
        if (dom_string_create_interned((const uint8_t *) #n,            \
                                       strlen(#n), &state.interned_##s) \
@@ -721,6 +746,19 @@ 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;
@@ -758,9 +796,116 @@ 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
@@ -800,9 +945,11 @@ svgtiny_code svgtiny_preparse_styles(dom_element *svg,
                                return svgtiny_LIBDOM_ERROR;
                        }
 
-                       if (dom_string_caseless_isequal(state.interned_style,
+                       if (dom_string_isequal(state.interned_style,
                                                        nodename)) {
                                /* We have a <style> element, parse it */
+                               code = svgtiny_parse_style_element(child,
+                                                               state);
                        }
 
 
@@ -825,7 +972,7 @@ svgtiny_code svgtiny_preparse_styles(dom_element *svg,
 }
 
 /**
- * Parse a <svg> or <g> element node.
+ * Parse <svg>, <g>, and <a> element nodes.
  */
 
 svgtiny_code svgtiny_parse_svg(dom_element *svg,
@@ -835,12 +982,14 @@ svgtiny_code svgtiny_parse_svg(dom_element *svg,
        dom_string *view_box;
        dom_element *child;
        dom_exception exc;
+       css_select_results *styles;
 
        svgtiny_setup_state_local(&state);
 
        svgtiny_parse_position_attributes(svg, state, &x, &y, &width, &height);
        svgtiny_parse_paint_attributes(svg, &state);
        svgtiny_parse_font_attributes(svg, &state);
+       styles = svgtiny_parse_styles(svg, &state);
 
        exc = dom_element_get_attribute(svg, state.interned_viewBox,
                                        &view_box);
@@ -878,6 +1027,14 @@ svgtiny_code svgtiny_parse_svg(dom_element *svg,
                dom_node_type nodetype;
                svgtiny_code code = svgtiny_OK;
 
+               /* Before we descend to one of my child elements, set
+                * the "parent style" to my style. */
+               if (styles) {
+                       /* For now at least, the root element won't
+                        * have any styles; hence the null check. */
+                       state.parent_style = styles->styles[CSS_PSEUDO_ELEMENT_NONE];
+               }
+
                exc = dom_node_get_node_type(child, &nodetype);
                if (exc != DOM_NO_ERR) {
                        dom_node_unref(child);
@@ -891,37 +1048,37 @@ svgtiny_code svgtiny_parse_svg(dom_element *svg,
                                svgtiny_cleanup_state_local(&state);
                                return svgtiny_LIBDOM_ERROR;
                        }
-                       if (dom_string_caseless_isequal(state.interned_svg,
+                       if (dom_string_isequal(state.interned_svg,
                                                        nodename))
                                code = svgtiny_parse_svg(child, state);
-                       else if (dom_string_caseless_isequal(state.interned_g,
+                       else if (dom_string_isequal(state.interned_g,
                                                             nodename))
                                code = svgtiny_parse_svg(child, state);
-                       else if (dom_string_caseless_isequal(state.interned_a,
+                       else if (dom_string_isequal(state.interned_a,
                                                             nodename))
                                code = svgtiny_parse_svg(child, state);
-                       else if (dom_string_caseless_isequal(state.interned_path,
+                       else if (dom_string_isequal(state.interned_path,
                                                             nodename))
                                code = svgtiny_parse_path(child, state);
-                       else if (dom_string_caseless_isequal(state.interned_rect,
+                       else if (dom_string_isequal(state.interned_rect,
                                                             nodename))
                                code = svgtiny_parse_rect(child, state);
-                       else if (dom_string_caseless_isequal(state.interned_circle,
+                       else if (dom_string_isequal(state.interned_circle,
                                                             nodename))
                                code = svgtiny_parse_circle(child, state);
-                       else if (dom_string_caseless_isequal(state.interned_ellipse,
+                       else if (dom_string_isequal(state.interned_ellipse,
                                                             nodename))
                                code = svgtiny_parse_ellipse(child, state);
-                       else if (dom_string_caseless_isequal(state.interned_line,
+                       else if (dom_string_isequal(state.interned_line,
                                                             nodename))
                                code = svgtiny_parse_line(child, state);
-                       else if (dom_string_caseless_isequal(state.interned_polyline,
+                       else if (dom_string_isequal(state.interned_polyline,
                                                             nodename))
                                code = svgtiny_parse_poly(child, state, false);
-                       else if (dom_string_caseless_isequal(state.interned_polygon,
+                       else if (dom_string_isequal(state.interned_polygon,
                                                             nodename))
                                code = svgtiny_parse_poly(child, state, true);
-                       else if (dom_string_caseless_isequal(state.interned_text,
+                       else if (dom_string_isequal(state.interned_text,
                                                             nodename))
                                code = svgtiny_parse_text(child, state);
                        dom_string_unref(nodename);
@@ -941,6 +1098,9 @@ svgtiny_code svgtiny_parse_svg(dom_element *svg,
                child = next;
        }
 
+       /* Hoping that destroying "styles" destroys state.parent_style
+        * as well. */
+       css_select_results_destroy(styles);
        svgtiny_cleanup_state_local(&state);
        return svgtiny_OK;
 }
@@ -972,6 +1132,7 @@ svgtiny_code svgtiny_parse_path(dom_element *path,
 
        svgtiny_parse_paint_attributes(path, &state);
        svgtiny_parse_transform_attributes(path, &state);
+       css_select_results_destroy(svgtiny_parse_styles(path, &state));
 
        /* read d attribute */
        exc = dom_element_get_attribute(path, state.interned_d, &path_d_str);
@@ -1327,6 +1488,7 @@ svgtiny_code svgtiny_parse_rect(dom_element *rect,
                        &x, &y, &width, &height);
        svgtiny_parse_paint_attributes(rect, &state);
        svgtiny_parse_transform_attributes(rect, &state);
+       css_select_results_destroy(svgtiny_parse_styles(rect, &state));
 
        p = malloc(13 * sizeof p[0]);
        if (!p) {
@@ -1403,6 +1565,7 @@ svgtiny_code svgtiny_parse_circle(dom_element *circle,
 
        svgtiny_parse_paint_attributes(circle, &state);
        svgtiny_parse_transform_attributes(circle, &state);
+       css_select_results_destroy(svgtiny_parse_styles(circle, &state));
 
        if (r < 0) {
                state.diagram->error_line = -1; /* circle->line; */
@@ -1519,6 +1682,7 @@ svgtiny_code svgtiny_parse_ellipse(dom_element *ellipse,
 
        svgtiny_parse_paint_attributes(ellipse, &state);
        svgtiny_parse_transform_attributes(ellipse, &state);
+       css_select_results_destroy(svgtiny_parse_styles(ellipse, &state));
 
        if (rx < 0 || ry < 0) {
                state.diagram->error_line = -1; /* ellipse->line; */
@@ -1636,6 +1800,7 @@ svgtiny_code svgtiny_parse_line(dom_element *line,
 
        svgtiny_parse_paint_attributes(line, &state);
        svgtiny_parse_transform_attributes(line, &state);
+       css_select_results_destroy(svgtiny_parse_styles(line, &state));
 
        p = malloc(7 * sizeof p[0]);
        if (!p) {
@@ -1680,6 +1845,7 @@ svgtiny_code svgtiny_parse_poly(dom_element *poly,
 
        svgtiny_parse_paint_attributes(poly, &state);
        svgtiny_parse_transform_attributes(poly, &state);
+       css_select_results_destroy(svgtiny_parse_styles(poly, &state));
 
        exc = dom_element_get_attribute(poly, state.interned_points,
                                        &points_str);
@@ -1794,8 +1960,8 @@ svgtiny_code svgtiny_parse_text(dom_element *text,
                                svgtiny_cleanup_state_local(&state);
                                return svgtiny_LIBDOM_ERROR;
                        }
-                       if (dom_string_caseless_isequal(nodename,
-                                                       state.interned_tspan))
+                       if (dom_string_isequal(nodename,
+                                               state.interned_tspan))
                                code = svgtiny_parse_text((dom_element *)child,
                                                          state);
                        dom_string_unref(nodename);
@@ -1968,6 +2134,8 @@ 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) {
+               /* Parse a few 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;
@@ -2126,6 +2294,92 @@ void svgtiny_parse_transform_attributes(dom_element *node,
        }
 }
 
+/**
+ * Parse element styles.
+ *
+ * First we parse any inline "style" attributes. We then compose the
+ * element's style with any parent styles. Finally, we compute any
+ * styles that we support and set the corresponding fields in the
+ * parser state.
+ */
+css_select_results *svgtiny_parse_styles(dom_element *node,
+                       struct svgtiny_parse_state *state)
+{
+       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;
+
+       /* The result of composing this node's styles with its
+        * parent's styles. */
+       css_computed_style *composed = NULL;
+
+       dom_exception exc;
+       dom_string *attr;
+
+       exc = dom_element_get_attribute(node, state->interned_style, &attr);
+       if (exc != DOM_NO_ERR) {
+               return NULL;
+       }
+       if (attr != NULL) {
+               inline_sheet = svgtiny_parse_style_inline(
+                                       (uint8_t *)dom_string_data(attr),
+                                       dom_string_byte_length(attr));
+               dom_string_unref(attr);
+       }
+
+       code = svgtiny_select_style(state, node, inline_sheet, &styles);
+       css_stylesheet_destroy(inline_sheet);
+       if (code != CSS_OK) {
+               return NULL;
+       }
+
+       if (state->parent_style != NULL) {
+               code = css_computed_style_compose(
+                               state->parent_style,
+                               styles->styles[CSS_PSEUDO_ELEMENT_NONE],
+                               &state->unit_ctx,
+                               &composed);
+
+               if (code != CSS_OK || composed == NULL) {
+                       /* This function promises to return a
+                        * fully-composed set of styles, so if
+                        * we can't do that, we should fail. */
+                       css_select_results_destroy(styles);
+                       return NULL;
+               }
+
+               /* Replace my original computed styles with the
+                * composed ones */
+               css_computed_style_destroy(
+                               styles->styles[CSS_PSEUDO_ELEMENT_NONE]);
+               styles->styles[CSS_PSEUDO_ELEMENT_NONE] = composed;
+       }
+
+       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);
+
+       state->fill_opacity = FIXTOFLT(fill_opacity);
+       state->stroke_opacity = FIXTOFLT(stroke_opacity);
+
+       return styles;
+}
 
 /**
  * Parse a transform string.
@@ -2253,6 +2507,8 @@ 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)