tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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message_window.h (2632B)

      1 // Copyright 2013 The Chromium Authors
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #ifndef BASE_WIN_MESSAGE_WINDOW_H_
      6 #define BASE_WIN_MESSAGE_WINDOW_H_
      7 
      8 #include <string>
      9 
     10 #include "base/base_export.h"
     11 #include "base/compiler_specific.h"
     12 #include "base/functional/callback.h"
     13 #include "base/threading/thread_checker.h"
     14 #include "base/win/windows_types.h"
     15 
     16 // Protect against windows.h being included before this header.
     17 #undef FindWindow
     18 
     19 namespace base {
     20 namespace win {
     21 
     22 // Implements a message-only window.
     23 class BASE_EXPORT MessageWindow {
     24 public:
     25  // Used to register a process-wide message window class.
     26  class WindowClass;
     27 
     28  // Implement this callback to handle messages received by the message window.
     29  // If the callback returns |false|, the first four parameters are passed to
     30  // DefWindowProc(). Otherwise, |*result| is returned by the window procedure.
     31  using MessageCallback =
     32      base::RepeatingCallback<bool(UINT message,
     33                                   WPARAM wparam,
     34                                   LPARAM lparam,
     35                                   LRESULT* result)>;  // NOLINT
     36 
     37  MessageWindow();
     38 
     39  MessageWindow(const MessageWindow&) = delete;
     40  MessageWindow& operator=(const MessageWindow&) = delete;
     41 
     42  ~MessageWindow();
     43 
     44  // Creates a message-only window. The incoming messages will be passed by
     45  // |message_callback|. |message_callback| must outlive |this|.
     46  bool Create(MessageCallback message_callback);
     47 
     48  // Same as Create() but assigns the name to the created window.
     49  bool CreateNamed(MessageCallback message_callback,
     50                   const std::wstring& window_name);
     51 
     52  HWND hwnd() const { return window_; }
     53 
     54  // Retrieves a handle of the first message-only window with matching
     55  // |window_name|.
     56  static HWND FindWindow(const std::wstring& window_name);
     57 
     58 private:
     59  // Give |WindowClass| access to WindowProc().
     60  friend class WindowClass;
     61 
     62  // Contains the actual window creation code.
     63  bool DoCreate(MessageCallback message_callback, const wchar_t* window_name);
     64 
     65  // Invoked by the OS to process incoming window messages.
     66  static LRESULT CALLBACK WindowProc(HWND hwnd,
     67                                     UINT message,
     68                                     WPARAM wparam,
     69                                     LPARAM lparam);
     70 
     71  // Invoked to handle messages received by the window.
     72  MessageCallback message_callback_;
     73 
     74  // Handle of the input window.
     75  HWND window_ = nullptr;
     76 
     77  THREAD_CHECKER(thread_checker_);
     78 };
     79 
     80 }  // namespace win
     81 }  // namespace base
     82 
     83 #endif  // BASE_WIN_MESSAGE_WINDOW_H_