Send WM_DEVICECHANGE message through SystemMonitor

content/browser/system_message_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 "content/browser/system_message_window_win.h"
+
+#include <windows.h>
+#include <dbt.h>
+
+#include "base/system_monitor/system_monitor.h"
+#include "base/win/wrapped_window_proc.h"
+
+static const wchar_t* const WindowClassName = L"Chrome_SystemMessageWindow";
+
+SystemMessageWindowWin::SystemMessageWindowWin() {
+  HINSTANCE hinst = GetModuleHandle(NULL);
+
+  WNDCLASSEX wc = {0};
+  wc.cbSize = sizeof(wc);
+  wc.lpfnWndProc =
+      base::win::WrappedWindowProc<&SystemMessageWindowWin::WndProcThunk>;
+  wc.hInstance = hinst;
+  wc.lpszClassName = WindowClassName;
+  ATOM clazz = RegisterClassEx(&wc);
+  DCHECK(clazz);
+
+  window_ = CreateWindow(WindowClassName,
+                         0, 0, 0, 0, 0, 0, 0, 0, hinst, 0);
+  SetWindowLongPtr(window_, GWLP_USERDATA, reinterpret_cast<LONG_PTR>(this));
+}
+
+SystemMessageWindowWin::~SystemMessageWindowWin() {
+  if (window_) {
+    DestroyWindow(window_);
+    UnregisterClass(WindowClassName, GetModuleHandle(NULL));
+  }
+}
+
+LRESULT SystemMessageWindowWin::OnDeviceChange(UINT event_type, DWORD data) {
+  base::SystemMonitor* monitor = base::SystemMonitor::Get();
+  if (monitor && event_type == DBT_DEVNODES_CHANGED)
+    monitor->ProcessDevicesChanged();
+  return TRUE;
+}
+
+LRESULT CALLBACK SystemMessageWindowWin::WndProc(HWND hwnd, UINT message,
+                                                 WPARAM wparam, LPARAM lparam) {
+  switch (message) {
+    case WM_DEVICECHANGE:
+      return OnDeviceChange(static_cast<UINT>(wparam),
+                            static_cast<DWORD>(lparam));
+    default:
+      break;
+  }
+
+  return ::DefWindowProc(hwnd, message, wparam, lparam);
+}