Proof of concept: Use a single FilterEngine instance

Shared/AdblockPlusClient.cpp

Index: Shared/AdblockPlusClient.cpp
===================================================================
--- a/Shared/AdblockPlusClient.cpp
+++ b/Shared/AdblockPlusClient.cpp
@@ -11,32 +11,185 @@
 
 #include "AdblockPlusClient.h"
 
+namespace
+{
+  const LPCWSTR responseClassName = L"FilterEngineResponse";
+  std::string response;
+  bool responseReady;
+
+  std::auto_ptr<AdblockPlus::FilterEngine> CreateFilterEngine()
+  {
+    try
+    {
+      DEBUG_GENERAL("Building client");
+      AdblockPlus::AppInfo appInfo;
+      appInfo.name = "adblockplusie";
+      appInfo.version = CT2CA(_T(IEPLUGIN_VERSION), CP_UTF8);
+      appInfo.platform = "msie";
+  
+      DEBUG_GENERAL(L"Building engine");
+
+      JsEnginePtr jsEngine(AdblockPlus::JsEngine::New(appInfo));
+      return std::auto_ptr<AdblockPlus::FilterEngine>(new AdblockPlus::FilterEngine(jsEngine));
+    }
+    catch(std::exception ex)
+    {
+      DEBUG_GENERAL(ex.what());
+    }
+  }
+
+  template<typename T>
+  std::wstring ToWString(const T& value)
+  {
+    std::wstringstream stream;
+    stream << value;
+    return stream.str();
+  }
+
+  std::wstring ToWString(LPCSTR value)
+  {
+    USES_CONVERSION;
+    return ToWString(A2W(value));
+  }
+
+  template<>
+  std::wstring ToWString(const std::string& value)
+  {
+    return ToWString(value.c_str());
+  }
+
+  template<typename T>
+  std::string ToString(const T& value)
+  {
+    std::stringstream stream;
+    stream << value;
+    return stream.str();
+  }
+
+  std::string ToString(LPCWSTR value)
+  {
+    USES_CONVERSION;
+    return ToString(W2A(value));
+  }
+
+  template<>
+  std::string ToString(const std::wstring& value)
+  {
+    return ToString(value.c_str());
+  }
+
+  std::string MarshalStrings(const std::vector<std::string>& strings)
+  {
+    std::string marshalledStrings;
+    for (std::vector<std::string>::const_iterator it = strings.begin(); it != strings.end(); it++)
+      marshalledStrings += *it + '\0';
+    return marshalledStrings;
+  }
+
+  std::vector<std::string> UnmarshalStrings(std::string::value_type* message, int count)
+  {
+    std::vector<std::string> strings;
+    for (int i = 0; i < count; i++)
+    {
+      std::string::value_type* part = message;
+      strings.push_back(message);
+      message += strlen(part) + 1;
+    }
+    return strings;
+  }
+
+  void SendStringMessage(HWND messageWindow, const std::string& message)
+  {
+    COPYDATASTRUCT data;
+    data.cbData = message.length() * sizeof(std::string::value_type);
+    data.lpData = (PVOID) message.c_str();
+    SendMessage(messageWindow, WM_COPYDATA, (WPARAM) messageWindow, (LPARAM)(LPVOID) &data);
+  }
+
+  LRESULT CALLBACK RequestWindowProcedure(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
+  {
+    if (uMsg == WM_COPYDATA)
+    {
+      COPYDATASTRUCT* data = (COPYDATASTRUCT*) lParam;
+      std::vector<std::string> args = UnmarshalStrings((std::string::value_type*) data->lpData, 4);
+
+      FilterEngine* filterEngine = (FilterEngine*) GetWindowLongPtr(hWnd, GWLP_USERDATA);
+      bool matches = filterEngine->Matches(args[1], args[2], args[3]);
+
+      std::wstring responseWindowName = ToWString(args[0]);
+      HWND responseWindow = FindWindowEx(HWND_MESSAGE, 0, responseClassName, responseWindowName.c_str());
+      if (!responseWindow)
+      {
+        DEBUG_GENERAL(L"Failed to find the filter engine response window");
+      }
+      else
+      {
+        SendStringMessage(responseWindow, ToString(matches));
+      }
+    }
+    return DefWindowProc(hWnd, uMsg, wParam, lParam);
+  }
+
+  LRESULT CALLBACK ResponseWindowProcedure(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
+  {
+    if (uMsg == WM_COPYDATA)
+    {
+      COPYDATASTRUCT* data = (COPYDATASTRUCT*) lParam;
+      response = (std::string::value_type*) data->lpData;
+      responseReady = true;
+    }
+    return DefWindowProc(hWnd, uMsg, wParam, lParam);
+  }
+}
 
 CAdblockPlusClient* CAdblockPlusClient::s_instance = NULL;
 
-
 CAdblockPlusClient::CAdblockPlusClient() : CPluginClientBase()
 {
-  try
+  m_filter = std::auto_ptr<CPluginFilter>(new CPluginFilter());
+
+  // TODO: Only create a single filter engine instance, share them across all
+  //       processes. For this we need to invoke all filter engine methods via
+  //       IPC. This is already done for FilterEngine::Matches().
+  filterEngine = CreateFilterEngine();
+
+  const LPCWSTR requestClassName = L"FilterEngineRequest";
+  WNDCLASS requestClass = {};
+  requestClass.lpfnWndProc = (WNDPROC) RequestWindowProcedure;
+  requestClass.lpszClassName = requestClassName;
+  if (!RegisterClass(&requestClass))
   {
-    DEBUG_GENERAL("Building client");
-    m_filter = std::auto_ptr<CPluginFilter>(new CPluginFilter());
-    AdblockPlus::AppInfo appInfo;
-    appInfo.name = "adblockplusie";
-    appInfo.version = CT2CA(_T(IEPLUGIN_VERSION), CP_UTF8);
-    appInfo.platform = "msie";
-  
-    DEBUG_GENERAL(L"Building engine");
+    DEBUG_GENERAL(L"Failed to register FilterEngineRequest class");
+    return;
+  }
 
-    JsEnginePtr jsEngine(AdblockPlus::JsEngine::New(appInfo));
-    filterEngine = std::auto_ptr<AdblockPlus::FilterEngine>(new AdblockPlus::FilterEngine(jsEngine));
+  filterEngineRequestWindow = FindWindowEx(HWND_MESSAGE, 0, requestClassName, 0);
+  if (!filterEngineRequestWindow)
+  {
+    filterEngineRequestWindow = CreateWindow(requestClassName, 0, 0, 0, 0, 0, 0, HWND_MESSAGE, 0, 0, 0);
+    if (!filterEngineRequestWindow)
+    {
+      DEBUG_GENERAL(L"Failed to create filter engine request window");
+      return;
+    }
+    SetWindowLongPtr(filterEngineRequestWindow, GWLP_USERDATA, (LONG_PTR) filterEngine.get());
+  }
 
+  WNDCLASS responseClass = {};
+  responseClass.lpfnWndProc = (WNDPROC) ResponseWindowProcedure;
+  responseClass.lpszClassName = responseClassName;
+  if (!RegisterClass(&responseClass))
+  {
+    DEBUG_GENERAL(L"Failed to register FilterEngineRequest class");
+    return;
   }
-  catch(std::exception ex)
-  {
-    DEBUG_GENERAL(ex.what());
-  }
+
+  filterEngineResponseWindowName = ToWString(GetCurrentThreadId());
+  filterEngineResponseWindow = CreateWindow(responseClassName, filterEngineResponseWindowName.c_str(), 0, 0, 0, 0, 0, HWND_MESSAGE, 0, 0, 0);
+  if (!filterEngineResponseWindow)
+    DEBUG_GENERAL(L"Failed to create filter engine response window");
 }
+
 CAdblockPlusClient::~CAdblockPlusClient()
 {
   s_instance = NULL;
@@ -163,3 +316,17 @@
   RegCloseKey(hKey);
   return (int)(version[0] - 48);
 }
+
+bool CAdblockPlusClient::Matches(const std::string& url, const std::string& contentType, const std::string& domain)
+{
+  std::vector<std::string> args;
+  args.push_back(ToString(filterEngineResponseWindowName));
+  args.push_back(url);
+  args.push_back(contentType);
+  args.push_back(domain);
+  responseReady = false;
+  SendStringMessage(filterEngineRequestWindow, MarshalStrings(args));
+  while (!responseReady)
+    Sleep(10);
+  return response == "1";
+}