1// Copyright (c) 2011 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "base/win/wrapped_window_proc.h"
6#include "base/message_loop.h"
7#include "testing/gtest/include/gtest/gtest.h"
8
9namespace {
10
11DWORD kExceptionCode = 12345;
12WPARAM kCrashMsg = 98765;
13
14// A trivial WindowProc that generates an exception.
15LRESULT CALLBACK TestWindowProc(HWND hwnd, UINT message,
16                                WPARAM wparam, LPARAM lparam) {
17  if (message == kCrashMsg)
18    RaiseException(kExceptionCode, 0, 0, NULL);
19  return DefWindowProc(hwnd, message, wparam, lparam);
20}
21
22// This class implements an exception filter that can be queried about a past
23// exception.
24class TestWrappedExceptionFiter {
25 public:
26  TestWrappedExceptionFiter() : called_(false) {
27    EXPECT_FALSE(s_filter_);
28    s_filter_ = this;
29  }
30
31  ~TestWrappedExceptionFiter() {
32    EXPECT_EQ(s_filter_, this);
33    s_filter_ = NULL;
34  }
35
36  bool called() {
37    return called_;
38  }
39
40  // The actual exception filter just records the exception.
41  static int Filter(EXCEPTION_POINTERS* info) {
42    EXPECT_FALSE(s_filter_->called_);
43    if (info->ExceptionRecord->ExceptionCode == kExceptionCode)
44      s_filter_->called_ = true;
45    return EXCEPTION_EXECUTE_HANDLER;
46  }
47
48 private:
49  bool called_;
50  static TestWrappedExceptionFiter* s_filter_;
51};
52TestWrappedExceptionFiter* TestWrappedExceptionFiter::s_filter_ = NULL;
53
54}  // namespace.
55
56TEST(WrappedWindowProc, CatchesExceptions) {
57  HINSTANCE hinst = GetModuleHandle(NULL);
58  std::wstring class_name(L"TestClass");
59
60  WNDCLASS wc = {0};
61  wc.lpfnWndProc = base::win::WrappedWindowProc<TestWindowProc>;
62  wc.hInstance = hinst;
63  wc.lpszClassName = class_name.c_str();
64  RegisterClass(&wc);
65
66  HWND window = CreateWindow(class_name.c_str(), 0, 0, 0, 0, 0, 0, HWND_MESSAGE,
67                             0, hinst, 0);
68  ASSERT_TRUE(window);
69
70  // Before generating the exception we make sure that the filter will see it.
71  TestWrappedExceptionFiter wrapper;
72  base::win::WinProcExceptionFilter old_filter =
73      base::win::SetWinProcExceptionFilter(TestWrappedExceptionFiter::Filter);
74
75  SendMessage(window, kCrashMsg, 0, 0);
76  EXPECT_TRUE(wrapper.called());
77
78  base::win::SetWinProcExceptionFilter(old_filter);
79}
80