1 // Copyright (c) 2012 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
7 #include "base/atomicops.h"
8 #include "base/check.h"
9 #include "base/notreached.h"
10 #include "base/strings/string_util.h"
11
12 namespace {
13
14 base::win::WinProcExceptionFilter s_exception_filter = nullptr;
15
GetModuleFromWndProc(WNDPROC window_proc)16 HMODULE GetModuleFromWndProc(WNDPROC window_proc) {
17 HMODULE instance = nullptr;
18 // Converting a pointer-to-function to a void* is undefined behavior, but
19 // Windows (and POSIX) APIs require it to work.
20 void* address = reinterpret_cast<void*>(window_proc);
21 if (!::GetModuleHandleExA(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS |
22 GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT,
23 static_cast<char*>(address), &instance)) {
24 NOTREACHED();
25 }
26 return instance;
27 }
28
29 } // namespace.
30
31 namespace base {
32 namespace win {
33
SetWinProcExceptionFilter(WinProcExceptionFilter filter)34 WinProcExceptionFilter SetWinProcExceptionFilter(
35 WinProcExceptionFilter filter) {
36 subtle::AtomicWord rv = subtle::NoBarrier_AtomicExchange(
37 reinterpret_cast<subtle::AtomicWord*>(&s_exception_filter),
38 reinterpret_cast<subtle::AtomicWord>(filter));
39 return reinterpret_cast<WinProcExceptionFilter>(rv);
40 }
41
CallExceptionFilter(EXCEPTION_POINTERS * info)42 int CallExceptionFilter(EXCEPTION_POINTERS* info) {
43 return s_exception_filter ? s_exception_filter(info)
44 : EXCEPTION_CONTINUE_SEARCH;
45 }
46
InitializeWindowClass(const wchar_t * class_name,WNDPROC window_proc,UINT style,int class_extra,int window_extra,HCURSOR cursor,HBRUSH background,const wchar_t * menu_name,HICON large_icon,HICON small_icon,WNDCLASSEX * class_out)47 BASE_EXPORT void InitializeWindowClass(const wchar_t* class_name,
48 WNDPROC window_proc,
49 UINT style,
50 int class_extra,
51 int window_extra,
52 HCURSOR cursor,
53 HBRUSH background,
54 const wchar_t* menu_name,
55 HICON large_icon,
56 HICON small_icon,
57 WNDCLASSEX* class_out) {
58 class_out->cbSize = sizeof(WNDCLASSEX);
59 class_out->style = style;
60 class_out->lpfnWndProc = window_proc;
61 class_out->cbClsExtra = class_extra;
62 class_out->cbWndExtra = window_extra;
63 // RegisterClassEx uses a handle of the module containing the window procedure
64 // to distinguish identically named classes registered in different modules.
65 class_out->hInstance = GetModuleFromWndProc(window_proc);
66 class_out->hIcon = large_icon;
67 class_out->hCursor = cursor;
68 class_out->hbrBackground = background;
69 class_out->lpszMenuName = menu_name;
70 class_out->lpszClassName = class_name;
71 class_out->hIconSm = small_icon;
72
73 // Check if |window_proc| is valid.
74 DCHECK(class_out->hInstance != nullptr);
75 }
76
77 } // namespace win
78 } // namespace base
79