src/svgtiny.c: eliminate pointless NULL check

[libsvgtiny.git] / src / svgtiny.c

diff --git a/src/svgtiny.c b/src/svgtiny.c
index 09adedc66799765c054267ba0c84269fa1e2aa96..a77e3b46d9f7c0ca382190075f6971af475c4da9 100644 (file)
--- a/src/svgtiny.c
+++ b/src/svgtiny.c
@@ -42,6 +42,8 @@
 
 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,
@@ -695,22 +697,21 @@ 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;
        }
 
 #define SVGTINY_STRING_ACTION2(s,n)                                    \
@@ -723,6 +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;
@@ -760,6 +774,11 @@ 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;
 }
 
@@ -772,27 +791,10 @@ svgtiny_code svgtiny_parse_style_element(dom_element *style,
                struct svgtiny_parse_state state)
 {
        css_stylesheet *sheet;
-       css_stylesheet_params params;
        css_error code;
        dom_exception exc;
 
-       params.params_version = CSS_STYLESHEET_PARAMS_VERSION_1;
-       params.level = CSS_LEVEL_DEFAULT;
-       params.charset = NULL;
-       params.url = "";
-       params.title = NULL;
-       params.allow_quirks = false;
-       params.inline_style = false;
-       params.resolve = svgtiny_resolve_url;
-       params.resolve_pw = NULL;
-       params.import = NULL;
-       params.import_pw = NULL;
-       params.color = NULL;
-       params.color_pw = NULL;
-       params.font = NULL;
-       params.font_pw = NULL;
-
-       code = css_stylesheet_create(&params, &sheet);
+       code = svgtiny_create_stylesheet(&sheet, false);
        if (code != CSS_OK) {
                return svgtiny_LIBCSS_ERROR;
        }
@@ -851,6 +853,37 @@ svgtiny_code svgtiny_parse_style_element(dom_element *style,
 }
 
 
+/**
+ * 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
@@ -2039,6 +2072,13 @@ void svgtiny_parse_paint_attributes(dom_element *node,
        dom_string *attr;
        dom_exception exc;
 
+       /* 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. We initialize inline_sheet to NULL to
+        * retain the same semantics. */
+       css_stylesheet *inline_sheet = NULL;
+
        exc = dom_element_get_attribute(node, state->interned_fill, &attr);
        if (exc == DOM_NO_ERR && attr != NULL) {
                svgtiny_parse_color(attr, &state->fill, &state->fill_grad, state);
@@ -2060,6 +2100,14 @@ 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;
@@ -2092,6 +2140,10 @@ void svgtiny_parse_paint_attributes(dom_element *node,
                free(style);
                dom_string_unref(attr);
        }
+
+       if (inline_sheet != NULL) {
+               css_stylesheet_destroy(inline_sheet);
+       }
 }