Make EventBindings use static routed methods.

chrome/renderer/extensions/event_bindings.cc

 // Copyright (c) 2012 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/extensions/event_bindings.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/basictypes.h"
@@ skipping 46 matching lines @@
 // track of which filters are in effect for which events.
 // We notify the browser about filtered event listeners when we transition
 // between 0 and 1.
 typedef std::map<std::string, linked_ptr<extensions::ValueCounter> >
     FilteredEventListenerCounts;
 
 // A map of extension IDs to filtered listener counts for that extension.
 base::LazyInstance<std::map<std::string, FilteredEventListenerCounts> >
     g_filtered_listener_counts = LAZY_INSTANCE_INITIALIZER;
 
+base::LazyInstance<extensions::EventFilter> g_event_filter =
+    LAZY_INSTANCE_INITIALIZER;
+
 // TODO(koz): Merge this into EventBindings.
 class ExtensionImpl : public ChromeV8Extension {
  public:
 
-  ExtensionImpl(ExtensionDispatcher* dispatcher,
-      extensions::EventFilter* event_filter)
-      : ChromeV8Extension(dispatcher),
-        event_filter_(event_filter) {
-    RouteFunction("AttachEvent",
-        base::Bind(&ExtensionImpl::AttachEvent,
-                   base::Unretained(this)));
-    RouteFunction("DetachEvent",
-        base::Bind(&ExtensionImpl::DetachEvent,
-                   base::Unretained(this)));
-    RouteFunction("AttachFilteredEvent",
-        base::Bind(&ExtensionImpl::AttachFilteredEvent,
-                   base::Unretained(this)));
-    RouteFunction("DetachFilteredEvent",
-        base::Bind(&ExtensionImpl::DetachFilteredEvent,
-                   base::Unretained(this)));
-    RouteFunction("MatchAgainstEventFilter",
-        base::Bind(&ExtensionImpl::MatchAgainstEventFilter,
-                   base::Unretained(this)));
+  explicit ExtensionImpl(ExtensionDispatcher* dispatcher)
+      : ChromeV8Extension(dispatcher) {
+    RouteStaticFunction("AttachEvent", &AttachEvent);
+    RouteStaticFunction("DetachEvent", &DetachEvent);
+    RouteStaticFunction("AttachFilteredEvent", &AttachFilteredEvent);
+    RouteStaticFunction("DetachFilteredEvent", &DetachFilteredEvent);
+    RouteStaticFunction("MatchAgainstEventFilter", &MatchAgainstEventFilter);
   }
+
   ~ExtensionImpl() {}
 
   // Attach an event name to an object.
-  v8::Handle<v8::Value> AttachEvent(const v8::Arguments& args) {
+  static v8::Handle<v8::Value> AttachEvent(const v8::Arguments& args) {
     DCHECK(args.Length() == 1);
     // TODO(erikkay) should enforce that event name is a string in the bindings
     DCHECK(args[0]->IsString() || args[0]->IsUndefined());
 
     if (args[0]->IsString()) {
+      ExtensionImpl* self = GetFromArguments<ExtensionImpl>(args);
       std::string event_name = *v8::String::AsciiValue(args[0]->ToString());
+      ExtensionDispatcher* extension_dispatcher = self->extension_dispatcher();
       const ChromeV8ContextSet& context_set =
-          extension_dispatcher()->v8_context_set();
+          extension_dispatcher->v8_context_set();
       ChromeV8Context* context = context_set.GetCurrent();
       CHECK(context);
 
-      if (!extension_dispatcher()->CheckCurrentContextAccessToExtensionAPI(
+      if (!extension_dispatcher->CheckCurrentContextAccessToExtensionAPI(
               event_name))
         return v8::Undefined();
 
       std::string extension_id = context->GetExtensionID();
       EventListenerCounts& listener_counts =
           g_listener_counts.Get()[extension_id];
       if (++listener_counts[event_name] == 1) {
         content::RenderThread::Get()->Send(
             new ExtensionHostMsg_AddListener(extension_id, event_name));
       }
 
       // This is called the first time the page has added a listener. Since
       // the background page is the only lazy page, we know this is the first
       // time this listener has been registered.
       if (IsLazyBackgroundPage(context->extension())) {
         content::RenderThread::Get()->Send(
             new ExtensionHostMsg_AddLazyListener(extension_id, event_name));
       }
     }
     return v8::Undefined();
   }
 
-  v8::Handle<v8::Value> DetachEvent(const v8::Arguments& args) {
+  static v8::Handle<v8::Value> DetachEvent(const v8::Arguments& args) {
     DCHECK(args.Length() == 2);
     // TODO(erikkay) should enforce that event name is a string in the bindings
     DCHECK(args[0]->IsString() || args[0]->IsUndefined());
 
     if (args[0]->IsString() && args[1]->IsBoolean()) {
       std::string event_name = *v8::String::AsciiValue(args[0]->ToString());
       bool is_manual = args[1]->BooleanValue();
 
+      ExtensionImpl* self = GetFromArguments<ExtensionImpl>(args);
+      ExtensionDispatcher* extension_dispatcher = self->extension_dispatcher();
       const ChromeV8ContextSet& context_set =
-          extension_dispatcher()->v8_context_set();
+          extension_dispatcher->v8_context_set();
       ChromeV8Context* context = context_set.GetCurrent();
       if (!context)
         return v8::Undefined();
 
       std::string extension_id = context->GetExtensionID();
       EventListenerCounts& listener_counts =
           g_listener_counts.Get()[extension_id];
 
       if (--listener_counts[event_name] == 0) {
         content::RenderThread::Get()->Send(
@@ skipping 10 matching lines @@
       }
     }
     return v8::Undefined();
   }
 
   // MatcherID AttachFilteredEvent(string event_name, object filter)
   // event_name - Name of the event to attach.
   // filter - Which instances of the named event are we interested in.
   // returns the id assigned to the listener, which will be returned from calls
   // to MatchAgainstEventFilter where this listener matches.
-  v8::Handle<v8::Value> AttachFilteredEvent(const v8::Arguments& args) {
+  static v8::Handle<v8::Value> AttachFilteredEvent(const v8::Arguments& args) {
     DCHECK_EQ(2, args.Length());
     DCHECK(args[0]->IsString());
     DCHECK(args[1]->IsObject());
 
+    ExtensionImpl* self = GetFromArguments<ExtensionImpl>(args);
+    ExtensionDispatcher* extension_dispatcher = self->extension_dispatcher();
     const ChromeV8ContextSet& context_set =
-        extension_dispatcher()->v8_context_set();
+        extension_dispatcher->v8_context_set();
     ChromeV8Context* context = context_set.GetCurrent();
     DCHECK(context);
     if (!context)
       return v8::Integer::New(-1);
 
     std::string event_name = *v8::String::AsciiValue(args[0]);
     // This method throws an exception if it returns false.
-    if (!extension_dispatcher()->CheckCurrentContextAccessToExtensionAPI(
+    if (!extension_dispatcher->CheckCurrentContextAccessToExtensionAPI(
             event_name))
       return v8::Undefined();
 
     std::string extension_id = context->GetExtensionID();
     if (extension_id.empty())
       return v8::Integer::New(-1);
 
     scoped_ptr<base::DictionaryValue> filter;
     scoped_ptr<content::V8ValueConverter> converter(
         content::V8ValueConverter::create());
 
     base::DictionaryValue* filter_dict = NULL;
     base::Value* filter_value = converter->FromV8Value(args[1]->ToObject(),
         v8::Context::GetCurrent());
     if (!filter_value->GetAsDictionary(&filter_dict)) {
       delete filter_value;
       return v8::Integer::New(-1);
     }
 
     filter.reset(filter_dict);
-    int id = event_filter_->AddEventMatcher(event_name, ParseEventMatcher(
+    extensions::EventFilter& event_filter = g_event_filter.Get();
+    int id = event_filter.AddEventMatcher(event_name, ParseEventMatcher(
         filter.get()));
 
     // Only send IPCs the first time a filter gets added.
     if (AddFilter(event_name, extension_id, filter.get())) {
       bool lazy = IsLazyBackgroundPage(context->extension());
       content::RenderThread::Get()->Send(
           new ExtensionHostMsg_AddFilteredListener(extension_id, event_name,
                                                    *filter, lazy));
     }
 
     return v8::Integer::New(id);
   }
 
   // Add a filter to |event_name| in |extension_id|, returning true if it
   // was the first filter for that event in that extension.
-  bool AddFilter(const std::string& event_name,
-                 const std::string& extension_id,
-                 base::DictionaryValue* filter) {
+  static bool AddFilter(const std::string& event_name,
+                        const std::string& extension_id,
+                        base::DictionaryValue* filter) {
     FilteredEventListenerCounts& counts =
         g_filtered_listener_counts.Get()[extension_id];
     FilteredEventListenerCounts::iterator it = counts.find(event_name);
     if (it == counts.end())
       counts[event_name].reset(new extensions::ValueCounter);
 
     int result = counts[event_name]->Add(*filter);
     return 1 == result;
   }
 
   // Remove a filter from |event_name| in |extension_id|, returning true if it
   // was the last filter for that event in that extension.
-  bool RemoveFilter(const std::string& event_name,
-                    const std::string& extension_id,
-                    base::DictionaryValue* filter) {
+  static bool RemoveFilter(const std::string& event_name,
+                           const std::string& extension_id,
+                           base::DictionaryValue* filter) {
     FilteredEventListenerCounts& counts =
         g_filtered_listener_counts.Get()[extension_id];
     FilteredEventListenerCounts::iterator it = counts.find(event_name);
     if (it == counts.end())
       return false;
     return 0 == it->second->Remove(*filter);
   }
 
   // void DetachFilteredEvent(int id, bool manual)
   // id     - Id of the event to detach.
   // manual - false if this is part of the extension unload process where all
   //          listeners are automatically detached.
-  v8::Handle<v8::Value> DetachFilteredEvent(const v8::Arguments& args) {
+  static v8::Handle<v8::Value> DetachFilteredEvent(const v8::Arguments& args) {
     DCHECK_EQ(2, args.Length());
     DCHECK(args[0]->IsInt32());
     DCHECK(args[1]->IsBoolean());
     bool is_manual = args[1]->BooleanValue();
+    ExtensionImpl* self = GetFromArguments<ExtensionImpl>(args);
+    ExtensionDispatcher* extension_dispatcher = self->extension_dispatcher();
     const ChromeV8ContextSet& context_set =
-        extension_dispatcher()->v8_context_set();
+        extension_dispatcher->v8_context_set();
     ChromeV8Context* context = context_set.GetCurrent();
     if (!context)
       return v8::Undefined();
 
     std::string extension_id = context->GetExtensionID();
     if (extension_id.empty())
       return v8::Undefined();
 
     int matcher_id = args[0]->Int32Value();
+    extensions::EventFilter& event_filter = g_event_filter.Get();
     extensions::EventMatcher* event_matcher =
-        event_filter_->GetEventMatcher(matcher_id);
+        event_filter.GetEventMatcher(matcher_id);
 
-    const std::string& event_name = event_filter_->GetEventName(matcher_id);
+    const std::string& event_name = event_filter.GetEventName(matcher_id);
 
     // Only send IPCs the last time a filter gets removed.
     if (RemoveFilter(event_name, extension_id, event_matcher->value())) {
       bool lazy = is_manual && IsLazyBackgroundPage(context->extension());
       content::RenderThread::Get()->Send(
           new ExtensionHostMsg_RemoveFilteredListener(extension_id, event_name,
                                                       *event_matcher->value(),
                                                       lazy));
     }
 
-    event_filter_->RemoveEventMatcher(matcher_id);
+    event_filter.RemoveEventMatcher(matcher_id);
 
     return v8::Undefined();
   }
 
-  v8::Handle<v8::Value> MatchAgainstEventFilter(const v8::Arguments& args) {
+  static v8::Handle<v8::Value> MatchAgainstEventFilter(
+      const v8::Arguments& args) {
     typedef std::set<extensions::EventFilter::MatcherID> MatcherIDs;
 
+    extensions::EventFilter& event_filter = g_event_filter.Get();
     std::string event_name = *v8::String::AsciiValue(args[0]->ToString());
     extensions::EventFilteringInfo info = ParseFromObject(args[1]->ToObject());
-    MatcherIDs matched_event_filters = event_filter_->MatchEvent(
+    MatcherIDs matched_event_filters = event_filter.MatchEvent(
         event_name, info);
     v8::Handle<v8::Array> array(v8::Array::New(matched_event_filters.size()));
     int i = 0;
     for (MatcherIDs::iterator it = matched_event_filters.begin();
          it != matched_event_filters.end(); ++it) {
       array->Set(v8::Integer::New(i++), v8::Integer::New(*it));
     }
     return array;
   }
 
-  extensions::EventFilteringInfo ParseFromObject(
+  static extensions::EventFilteringInfo ParseFromObject(
       v8::Handle<v8::Object> object) {
     extensions::EventFilteringInfo info;
     v8::Handle<v8::String> url(v8::String::New("url"));
     if (object->Has(url)) {
       v8::Handle<v8::Value> url_value(object->Get(url));
       info.SetURL(GURL(*v8::String::AsciiValue(url_value)));
     }
     return info;
   }
 
  private:
-  extensions::EventFilter* event_filter_;
-  bool IsLazyBackgroundPage(const Extension* extension) {
+  static bool IsLazyBackgroundPage(const Extension* extension) {
     content::RenderView* render_view = GetCurrentRenderView();
     if (!render_view)
       return false;
 
     ExtensionHelper* helper = ExtensionHelper::Get(render_view);
     return (extension && extension->has_lazy_background_page() &&
             helper->view_type() == chrome::VIEW_TYPE_EXTENSION_BACKGROUND_PAGE);
   }
 
-  scoped_ptr<extensions::EventMatcher> ParseEventMatcher(
+  static scoped_ptr<extensions::EventMatcher> ParseEventMatcher(
       base::DictionaryValue* filter_dict) {
     return scoped_ptr<extensions::EventMatcher>(new extensions::EventMatcher(
         scoped_ptr<base::DictionaryValue>(filter_dict->DeepCopy())));
   }
 };
 
 }  // namespace
 
 // static
-ChromeV8Extension* EventBindings::Get(ExtensionDispatcher* dispatcher,
-    extensions::EventFilter* event_filter) {
-  return new ExtensionImpl(dispatcher, event_filter);
+ChromeV8Extension* EventBindings::Get(ExtensionDispatcher* dispatcher) {
+  return new ExtensionImpl(dispatcher);
 }