CSS bug 766: Parse the id and class attributes in advance.

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src/document/css/apply.c

@@ -120,7 +120,6 @@ examine_element(struct html_context *html_context, struct css_selector *base,
                 struct list_head *selectors, struct html_element *element)
 {
 	struct css_selector *selector;
-	unsigned char *code;
 
 #ifdef DEBUG_CSS
 	/* Cannot use list_empty() inside the arglist of DBG() because
@@ -191,29 +190,27 @@ examine_element(struct html_context *html_context, struct css_selector *base,
 		process_found_selector(selector, CST_PSEUDO, base);
 	}
 
-	code = get_attr_val(element->options, "class", html_context->doc_cp);
-	if (code && seltype <= CST_CLASS) {
-		unsigned char *class = code;
+	if (element->attr.class && seltype <= CST_CLASS) {
+		const unsigned char *class = element->attr.class;
 
-		while (class) {
-			unsigned char *end = strchr(class, ' ');
+		for (;;) {
+			const unsigned char *begin;
 
-			if (end)
-				*end++ = 0;
+			while (*class == ' ') ++class;
+			if (*class == '\0') break;
+			begin = class;
+			while (*class != ' ' && *class != '\0') ++class;
 
-			selector = find_css_selector(selectors, CST_CLASS, rel, class, -1);
+			selector = find_css_selector(selectors, CST_CLASS, rel,
+						     begin, class - begin);
 			process_found_selector(selector, CST_CLASS, base);
-			class = end;
 		}
 	}
-	mem_free_if(code);
 
-	code = get_attr_val(element->options, "id", html_context->doc_cp);
-	if (code && seltype <= CST_ID) {
-		selector = find_css_selector(selectors, CST_ID, rel, code, -1);
+	if (element->attr.id && seltype <= CST_ID) {
+		selector = find_css_selector(selectors, CST_ID, rel, element->attr.id, -1);
 		process_found_selector(selector, CST_ID, base);
 	}
-	if (code) mem_free(code);
 
 #undef process_found_selector
 #undef dbginfo

src/document/css/stylesheet.c

@@ -27,7 +27,7 @@
 struct css_selector *
 find_css_selector(struct list_head *sels, enum css_selector_type type,
                   enum css_selector_relation rel,
-                  unsigned char *name, int namelen)
+                  const unsigned char *name, int namelen)
 {
 	struct css_selector *selector;
 

src/document/css/stylesheet.h

@@ -120,7 +120,7 @@ struct css_selector *get_css_selector(struct list_head *selector_list,
 struct css_selector *find_css_selector(struct list_head *selector_list,
                                        enum css_selector_type type,
                                        enum css_selector_relation rel,
-                                       unsigned char *name, int namelen);
+                                       const unsigned char *name, int namelen);
 
 #define find_css_base_selector(stylesheet, type, rel, name, namelen) \
 	find_css_selector(&stylesheet->selectors, rel, type, name, namelen)

src/document/html/parser.h

@@ -52,6 +52,16 @@ struct text_attrib {
 #endif
 	color_T image_link;
 
+#ifdef CONFIG_CSS
+	/* Bug 766: CSS speedup.  56% of CPU time was going to
+	 * get_attr_value().  Of those calls, 97% were asking for "id"
+	 * or "class".  So cache the results.  start_element() sets up
+	 * these pointers if html_context->options->css_enable;
+	 * otherwise they remain NULL. */
+	unsigned char *id;
+	unsigned char *class;
+#endif
+
 	unsigned char *select;
 	int select_disabled;
 	unsigned int tabindex;

src/document/html/parser/parse.c

@@ -905,6 +905,10 @@ start_element(struct element_info *ei,
 		 * usually have type != ET_NESTABLE when we either (1)
 		 * rescan on your own from somewhere else (2) html_stack_dup()
 		 * in our own way.  --pasky */
+		mem_free_set(&html_top->attr.id,
+			     get_attr_val(attr, "id", html_context->doc_cp));
+		mem_free_set(&html_top->attr.class,
+			     get_attr_val(attr, "class", html_context->doc_cp));
 		/* Call it now to gain some of the stuff which might affect
 		 * formatting of some elements. */
 		/* FIXME: The caching of the CSS selector is broken, since t can

src/document/html/parser/stack.c

@@ -107,6 +107,11 @@ kill_html_stack_item(struct html_context *html_context, struct html_element *e)
 	mem_free_if(e->attr.title);
 	mem_free_if(e->attr.select);
 
+#ifdef CONFIG_CSS
+	mem_free_if(e->attr.id);
+	mem_free_if(e->attr.class);
+#endif
+
 	mem_free_if(e->attr.onclick);
 	mem_free_if(e->attr.ondblclick);
 	mem_free_if(e->attr.onmouseover);
@@ -146,6 +151,8 @@ html_stack_dup(struct html_context *html_context, enum html_element_mortality_ty
 	if (ep->attr.title) e->attr.title = stracpy(ep->attr.title);
 	if (ep->attr.select) e->attr.select = stracpy(ep->attr.select);
 
+	e->attr.id = e->attr.class = NULL;
+
 	/* We don't want to propagate these. */
 	/* XXX: For sure? --pasky */
 	e->attr.onclick = e->attr.ondblclick = e->attr.onmouseover = e->attr.onhover