Moved remoting::win::MessageWindow to base::win::MessageWindow so that it could be re-used outside …

base/win/message_window.cc

 // Copyright 2013 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 "remoting/host/win/message_window.h"
+#include "base/win/message_window.h"
 
 #include "base/logging.h"
 #include "base/process_util.h"
+#include "base/strings/string16.h"
 #include "base/strings/stringprintf.h"
-#include "base/strings/utf_string_conversions.h"
 #include "base/win/wrapped_window_proc.h"
 
-const char kClassNameFormat[] = "Chromoting_MessageWindow_%p";
+const wchar_t kClassNameFormat[] = L"Chrome_MessageWindow_%p";
 
-namespace remoting {
+namespace base {
 namespace win {
 
 MessageWindow::MessageWindow()
     : atom_(0),
-      instance_(NULL),
-      window_(NULL) {
-  class_name_ = base::StringPrintf(kClassNameFormat, this);
-  instance_ = base::GetModuleFromAddress(static_cast<WNDPROC>(
-      &base::win::WrappedWindowProc<WindowProc>));
-}
-
-MessageWindow::MessageWindow(const std::string& class_name, HINSTANCE instance)
-    : atom_(0),
-      class_name_(class_name),
-      instance_(instance),
       window_(NULL) {
 }
 
 MessageWindow::~MessageWindow() {
   DCHECK(CalledOnValidThread());
 
   if (window_ != NULL) {
-    DestroyWindow(window_);
-    window_ = NULL;
+    BOOL result = DestroyWindow(window_);
+    DCHECK(result);
   }
 
   if (atom_ != 0) {
-    UnregisterClass(MAKEINTATOM(atom_), instance_);
-    atom_ = 0;
+    BOOL result = UnregisterClass(
+        MAKEINTATOM(atom_),
+        base::GetModuleFromAddress(&MessageWindow::WindowProc));
+    DCHECK(result);
   }
 }
 
-bool MessageWindow::Create(Delegate* delegate) {
+bool MessageWindow::Create(Delegate* delegate, const wchar_t* window_name) {
   DCHECK(CalledOnValidThread());
   DCHECK(!atom_);
   DCHECK(!window_);
 
   // Register a separate window class for each instance of |MessageWindow|.
-  string16 class_name = UTF8ToUTF16(class_name_);
+  string16 class_name = base::StringPrintf(kClassNameFormat, this);
+  HINSTANCE instance = base::GetModuleFromAddress(&MessageWindow::WindowProc);
+
   WNDCLASSEX window_class;
   window_class.cbSize = sizeof(window_class);
   window_class.style = 0;
   window_class.lpfnWndProc = &base::win::WrappedWindowProc<WindowProc>;
   window_class.cbClsExtra = 0;
   window_class.cbWndExtra = 0;
-  window_class.hInstance = instance_;
+  window_class.hInstance = instance;
   window_class.hIcon = NULL;
   window_class.hCursor = NULL;
   window_class.hbrBackground = NULL;
   window_class.lpszMenuName = NULL;
   window_class.lpszClassName = class_name.c_str();
   window_class.hIconSm = NULL;
   atom_ = RegisterClassEx(&window_class);
   if (atom_ == 0) {
     LOG_GETLASTERROR(ERROR)
-        << "Failed to register the window class '" << class_name_ << "'";
+        << "Failed to register the window class for a message-only window";
     return false;
   }
 
-  window_ = CreateWindow(MAKEINTATOM(atom_), 0, 0, 0, 0, 0, 0, HWND_MESSAGE, 0,
-                         instance_, delegate);
+  window_ = CreateWindow(MAKEINTATOM(atom_), window_name, 0, 0, 0, 0, 0,
+                         HWND_MESSAGE, 0, instance, delegate);
   if (!window_) {
     LOG_GETLASTERROR(ERROR) << "Failed to create a message-only window";
     return false;
   }
 
   return true;
 }
 
 // static
 LRESULT CALLBACK MessageWindow::WindowProc(HWND hwnd,
                                            UINT message,
                                            WPARAM wparam,
                                            LPARAM lparam) {
-  Delegate* delegate = NULL;
+  Delegate* delegate = reinterpret_cast<Delegate*>(
+      GetWindowLongPtr(hwnd, GWLP_USERDATA));
 
-  // Set up the delegate before handling WM_CREATE.
-  if (message == WM_CREATE) {
-    CREATESTRUCT* cs = reinterpret_cast<CREATESTRUCT*>(lparam);
-    delegate = reinterpret_cast<Delegate*>(cs->lpCreateParams);
+  switch (message) {
+    // Set up the delegate before handling WM_CREATE.
+    case WM_CREATE: {
+      CREATESTRUCT* cs = reinterpret_cast<CREATESTRUCT*>(lparam);
+      delegate = reinterpret_cast<Delegate*>(cs->lpCreateParams);
 
-    // Store pointer to the delegate to the window's user data.
-    SetLastError(ERROR_SUCCESS);
-    LONG_PTR result = SetWindowLongPtr(
-        hwnd, GWLP_USERDATA, reinterpret_cast<LONG_PTR>(delegate));
-    CHECK(result != 0 || GetLastError() == ERROR_SUCCESS);
-  } else {
-    delegate = reinterpret_cast<Delegate*>(GetWindowLongPtr(hwnd,
-                                                            GWLP_USERDATA));
+      // Store pointer to the delegate to the window's user data.
+      SetLastError(ERROR_SUCCESS);
+      LONG_PTR result = SetWindowLongPtr(
+          hwnd, GWLP_USERDATA, reinterpret_cast<LONG_PTR>(delegate));
+      CHECK(result != 0 || GetLastError() == ERROR_SUCCESS);
+      break;
+    }
+
+    // Clear the pointer to stop calling the delegate once WM_DESTROY is
+    // received.
+    case WM_DESTROY: {
+      SetLastError(ERROR_SUCCESS);
+      LONG_PTR result = SetWindowLongPtr(hwnd, GWLP_USERDATA, NULL);
+      CHECK(result != 0 || GetLastError() == ERROR_SUCCESS);
+      break;
+    }
   }
 
   // Handle the message.
   if (delegate) {
     LRESULT message_result;
     if (delegate->HandleMessage(hwnd, message, wparam, lparam, &message_result))
       return message_result;
   }
 
   return DefWindowProc(hwnd, message, wparam, lparam);
 }
 
 }  // namespace win
-}  // namespace remoting
+}  // namespace base