Stop copying script contents for each RenderFrames.

extensions/renderer/user_script_set.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/renderer/user_script_set.h"
 
 #include <stddef.h>
 
 #include <utility>
 
@@ skipping 13 matching lines @@
 #include "extensions/renderer/user_script_injector.h"
 #include "extensions/renderer/web_ui_injection_host.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
 #include "third_party/WebKit/public/web/WebLocalFrame.h"
 #include "url/gurl.h"
 
 namespace extensions {
 
 namespace {
 
+// These two strings are injected before and after the Greasemonkey API and
+// user script to wrap it in an anonymous scope.
+const char kUserScriptHead[] = "(function (unsafeWindow) {\n";
+const char kUserScriptTail[] = "\n})(window);";
+
 GURL GetDocumentUrlForFrame(blink::WebLocalFrame* frame) {
   GURL data_source_url = ScriptContext::GetDataSourceURLForFrame(frame);
   if (!data_source_url.is_empty() && frame->isViewSourceModeEnabled()) {
     data_source_url = GURL(content::kViewSourceScheme + std::string(":") +
                            data_source_url.spec());
   }
 
   return data_source_url;
 }
 
@@ skipping 62 matching lines @@
     return false;
 
   // Unpickle scripts.
   uint32_t num_scripts = 0;
   base::Pickle pickle(reinterpret_cast<char*>(shared_memory_->memory()),
                       pickle_size);
   base::PickleIterator iter(pickle);
   CHECK(iter.ReadUInt32(&num_scripts));
 
   scripts_.clear();
+  script_sources_.clear();
   scripts_.reserve(num_scripts);
   for (uint32_t i = 0; i < num_scripts; ++i) {
     std::unique_ptr<UserScript> script(new UserScript());
     script->Unpickle(pickle, &iter);
 
     // Note that this is a pointer into shared memory. We don't own it. It gets
     // cleared up when the last renderer or browser process drops their
     // reference to the shared memory.
     for (size_t j = 0; j < script->js_scripts().size(); ++j) {
       const char* body = NULL;
@@ skipping 93 matching lines @@
   bool inject_js =
       !script->js_scripts().empty() && script->run_location() == run_location;
   if (inject_css || inject_js) {
     injection.reset(new ScriptInjection(std::move(injector), render_frame,
                                         std::move(injection_host), run_location,
                                         log_activity));
   }
   return injection;
 }
 
+blink::WebString UserScriptSet::GetJsSource(const UserScript::File& file,
+                                            bool emulate_greasemonkey) {
+  const GURL& url = file.url();
+  std::map<GURL, blink::WebString>::iterator iter = script_sources_.find(url);
+  if (iter != script_sources_.end())
+    return iter->second;
+
+  base::StringPiece script_content = file.GetContent();
+  blink::WebString source;
+  if (emulate_greasemonkey) {
+    // We add this dumb function wrapper for user scripts to emulate what
+    // Greasemonkey does. |script_content| becomes:
+    // concat(kUserScriptHead, script_content, kUserScriptTail).
+    std::string content;
+    content.reserve(strlen(kUserScriptHead) + script_content.length() +
+                    strlen(kUserScriptTail));
+    content.append(kUserScriptHead);
+    script_content.AppendToString(&content);
+    content.append(kUserScriptTail);
+    source = blink::WebString::fromUTF8(content);
+  } else {
+    source = blink::WebString::fromUTF8(script_content.data(),
+                                        script_content.length());
+  }
+  script_sources_[url] = source;
+  return source;
+}
+
+blink::WebString UserScriptSet::GetCssSource(const UserScript::File& file) {
+  const GURL& url = file.url();
+  std::map<GURL, blink::WebString>::iterator iter = script_sources_.find(url);
+  if (iter != script_sources_.end())
+    return iter->second;
+
+  base::StringPiece script_content = file.GetContent();
+  return script_sources_
+      .insert(std::make_pair(
+          url, blink::WebString::fromUTF8(script_content.data(),
+                                          script_content.length())))
+      .first->second;
+}
+
 }  // namespace extensions