Implement chromium.self in content scripts, fix bugs

chrome/renderer/user_script_slave.cc

 // Copyright (c) 2009 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 "chrome/renderer/user_script_slave.h"
 
 #include "base/histogram.h"
 #include "base/logging.h"
 #include "base/perftimer.h"
 #include "base/pickle.h"
 #include "base/shared_memory.h"
 #include "base/string_util.h"
 #include "chrome/common/resource_bundle.h"
 #include "googleurl/src/gurl.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebScriptSource.h"
 #include "webkit/glue/webframe.h"
 
 #include "grit/renderer_resources.h"
 
 using WebKit::WebScriptSource;
 using WebKit::WebString;
 
 // These two strings are injected before and after the Greasemonkey API and
 // user script to wrap it in an anonymous scope.
 static const char kUserScriptHead[] = "(function (unsafeWindow) {\n";
 static const char kUserScriptTail[] = "\n})(window);";
 
+static const char kInitSelf[] = "chromium.self = new chromium.Extension('%s')";
+
 UserScriptSlave::UserScriptSlave()
     : shared_memory_(NULL),
       script_deleter_(&scripts_),
       user_script_start_line_(0) {
   // TODO: Only windows supports resources and only windows supports user
   // scrips, so only load the Greasemonkey API on windows.  Fix this when
   // better cross platofrm support is available.
 #if defined(OS_WIN)
   api_js_ = ResourceBundle::GetSharedInstance().GetRawDataResource(
                 IDR_GREASEMONKEY_API_JS);
@@ skipping 65 matching lines @@
   }
 
   return true;
 }
 
 bool UserScriptSlave::InjectScripts(WebFrame* frame,
                                     UserScript::RunLocation location) {
   PerfTimer timer;
   int num_matched = 0;
 
-  std::vector<WebScriptSource> sources;
   for (size_t i = 0; i < scripts_.size(); ++i) {
+    std::vector<WebScriptSource> sources;
     UserScript* script = scripts_[i];
     if (!script->MatchesUrl(frame->GetURL()))
       continue;  // This frame doesn't match the script url pattern, skip it.
 
     ++num_matched;
     // CSS files are always injected on document start before js scripts.
     if (location == UserScript::DOCUMENT_START) {
       for (size_t j = 0; j < script->css_scripts().size(); ++j) {
         UserScript::File& file = script->css_scripts()[j];
         frame->InsertCSSStyles(file.GetContent().as_string());
       }
     }
     if (script->run_location() == location) {
       for (size_t j = 0; j < script->js_scripts().size(); ++j) {
         UserScript::File &file = script->js_scripts()[j];
+        std::string content = file.GetContent().as_string();
+
+        // We add this dumb function wrapper for standalone user script to
+        // emulate what Greasemonkey does.
+        if (script->is_standalone()) {
+          content.insert(0, kUserScriptHead);
+          content += kUserScriptTail;
+        }
         sources.push_back(WebScriptSource(
-            WebString::fromUTF8(file.GetContent()), file.url()));
+            WebString::fromUTF8(content.c_str(), content.length()),
+            file.url()));
       }
     }
+
+    if (!sources.empty()) {
+      if (script->is_standalone()) {
+        // For standalone scripts, we try to emulate the Greasemonkey API.
+        sources.insert(sources.begin(),
+            WebScriptSource(WebString::fromUTF8(api_js_.as_string())));
+      } else {
+        // Setup chromium.self to contain an Extension object with the correct
+        // ID.
+        sources.insert(sources.begin(),
+            WebScriptSource(WebString::fromUTF8(
+                StringPrintf(kInitSelf, script->extension_id().c_str()))));
+      }
+
+      frame->ExecuteScriptInNewContext(&sources.front(), sources.size());
+    }
   }
 
-  if (!sources.empty()) {
-    sources.insert(
-        sources.begin(), WebScriptSource(WebString::fromUTF8(api_js_)));
-    frame->ExecuteScriptInNewContext(&sources.front(), sources.size());
-  }
-
   // Log debug info.
   if (location == UserScript::DOCUMENT_START) {
     HISTOGRAM_COUNTS_100("UserScripts:DocStart:Count", num_matched);
     HISTOGRAM_TIMES("UserScripts:DocStart:Time", timer.Elapsed());
   } else {
     HISTOGRAM_COUNTS_100("UserScripts:DocEnd:Count", num_matched);
     HISTOGRAM_TIMES("UserScripts:DocEnd:Time", timer.Elapsed());
   }
 
   LOG(INFO) << "Injected " << num_matched << " user scripts into " <<
       frame->GetURL().spec();
   return true;
 }