Chromoting's ContinueWindow implementation for Windows.

remoting/host/continue_window_win.cc

 // Copyright (c) 2011 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/continue_window.h"
 
+#include <windows.h>
+
 #include "base/compiler_specific.h"
 #include "base/logging.h"
+#include "remoting/host/chromoting_host.h"
+#include "remoting/host/host_plugin_resource.h"
+
+// TODO(garykac): Lots of duplicated code in this file and
+// disconnect_window_win.cc. These global floating windows are temporary so
+// they should be deleted soon. If we need to expand this then we should
+// create a class with the shared code.
+
+// HMODULE from DllMain/WinMain. This is needed to find our dialog resource.
+// This is defined in:
+//   Plugin: host_plugin.cc
+//   SimpleHost: simple_host_process.cc
+extern HMODULE g_hModule;
 
 namespace remoting {
 
-class ContinueWindowWin : public remoting::ContinueWindow {
+class ContinueWindowWin : public ContinueWindow {
  public:
-  ContinueWindowWin() {}
-  virtual ~ContinueWindowWin() {}
+  ContinueWindowWin();
+  virtual ~ContinueWindowWin();
 
   virtual void Show(remoting::ChromotingHost* host) OVERRIDE;
   virtual void Hide() OVERRIDE;
 
  private:
+  static BOOL CALLBACK DialogProc(HWND hwmd, UINT msg, WPARAM wParam,
+                                  LPARAM lParam);
+
+  BOOL OnDialogMessage(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
+
+  void EndDialog();
+
+  remoting::ChromotingHost* host_;
+  HWND hwnd_;
+
+  // A "random" key from the tickcount that is used to validate the WM_USER
+  // message sent to end the dialog. This check is used to help protect
+  // against someone sending (WM_APP,0,0L) to close the dialog.
+  DWORD key_;

[Jamie, 2011/06/21 23:09:45]

What is this designed to protect against? EndDialog is called in response to
WM_COMMAND anyway, so the dialog can be dismissed that way. Of course, that also
reactivates the session; is |key_| intended to prevent someone hiding the dialog
and preventing the user from using it to continue the session? If so, then it
seems like there are easier ways of doing that than sending WM_USER.

[garykac, 2011/06/22 00:36:59]

Removed. Now that we're on the proper thread, I'm not seeing the problems that
led me to introduce this.

+
   DISALLOW_COPY_AND_ASSIGN(ContinueWindowWin);
 };
 
-void ContinueWindowWin::Show(remoting::ChromotingHost* host) {
-  NOTIMPLEMENTED();
+ContinueWindowWin::ContinueWindowWin()
+    : host_(NULL),
+      hwnd_(NULL),
+      key_(0L) {
+}
+
+ContinueWindowWin::~ContinueWindowWin() {
+  EndDialog();
+}
+
+BOOL CALLBACK ContinueWindowWin::DialogProc(HWND hwnd, UINT msg,
+                                            WPARAM wParam, LPARAM lParam) {
+  ContinueWindowWin* win = NULL;
+  if (msg == WM_INITDIALOG) {
+    win = reinterpret_cast<ContinueWindowWin*>(lParam);
+    CHECK(win);
+    SetWindowLongPtr(hwnd, DWLP_USER, (LONG_PTR)win);
+  } else {
+    LONG_PTR lp = GetWindowLongPtr(hwnd, DWLP_USER);
+    win = reinterpret_cast<ContinueWindowWin*>(lp);
+  }
+  if (win == NULL)
+    return FALSE;
+  return win->OnDialogMessage(hwnd, msg, wParam, lParam);
+}
+
+BOOL ContinueWindowWin::OnDialogMessage(HWND hwnd, UINT msg,
+                                        WPARAM wParam, LPARAM lParam) {
+  switch (msg) {
+    case WM_INITDIALOG:
+      return TRUE;
+    case WM_CLOSE:
+      // Ignore close messages.
+      return TRUE;
+    case WM_DESTROY:
+      // Ensure we don't try to use the HWND anymore.
+      hwnd_ = NULL;
+      return TRUE;
+    case WM_APP:

[Jamie, 2011/06/21 23:09:45]

I think WM_USER would be more appropriate here.

[garykac, 2011/06/22 00:36:59]

Removed.

+      if (key_ == static_cast<DWORD>(lParam)) {
+        ::EndDialog(hwnd, LOWORD(wParam));
+        hwnd_ = NULL;
+      }
+      return TRUE;
+    case WM_COMMAND:
+      switch (LOWORD(wParam)) {
+        case IDC_CONTINUE:
+          {
+            CHECK(host_);
+            host_->PauseSession(false);
+            ::EndDialog(hwnd, LOWORD(wParam));
+            hwnd_ = NULL;
+          }
+          return TRUE;
+      }
+  }
+  return FALSE;
+}
+
+void ContinueWindowWin::Show(ChromotingHost* host) {
+  host_ = host;
+  // Get a "random" value that we can use to prevent someone from sending a
+  // simple (WM_APP,0,0L) message to our window to close it.
+  key_ = GetTickCount();
+
+  CHECK(!hwnd_);
+  hwnd_ = CreateDialogParam(g_hModule, MAKEINTRESOURCE(IDD_CONTINUE), NULL,
+      (DLGPROC)DialogProc, (LPARAM)this);
+  if (!hwnd_) {
+    LOG(ERROR) << "Unable to create Disconnect dialog for remoting.";
+    return;
+  }
+
+  ShowWindow(hwnd_, SW_SHOW);
 }
 
 void ContinueWindowWin::Hide() {
-  NOTIMPLEMENTED();
+  EndDialog();
+}
+
+void ContinueWindowWin::EndDialog() {
+  if (hwnd_) {
+    SendMessage(hwnd_, WM_APP, 0, (LPARAM)key_);
+  }
 }
 
 ContinueWindow* ContinueWindow::Create() {
   return new ContinueWindowWin();
 }
 
 }  // namespace remoting