widget/windows/WindowHook.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef __mozilla_WindowHook_h__
   8 #define __mozilla_WindowHook_h__
   9
  10 #include <windows.h>
  11
  12 #include <nsHashKeys.h>
  13 #include <nsClassHashtable.h>
  14 #include <nsTArray.h>
  15
  16 #include "nsAppShell.h"
  17
  18 class nsWindow;
  19
  20 namespace mozilla {
  21 namespace widget {
  22
  23 struct MSGResult;
  24
  25 class WindowHook {
  26  public:
  27   // It is expected that most callbacks will return false
  28   typedef bool (*Callback)(void* aContext, HWND hWnd, UINT nMsg, WPARAM wParam,
  29                            LPARAM lParam, LRESULT* aResult);
  30
  31   nsresult AddHook(UINT nMsg, Callback callback, void* context);
  32   nsresult RemoveHook(UINT nMsg, Callback callback, void* context);
  33   nsresult AddMonitor(UINT nMsg, Callback callback, void* context);
  34   nsresult RemoveMonitor(UINT nMsg, Callback callback, void* context);
  35
  36  private:
  37   struct CallbackData {
  38     Callback cb;
  39     void* context;
  40
  41     CallbackData() : cb(nullptr), context(nullptr) {}
  42     CallbackData(Callback cb, void* ctx) : cb(cb), context(ctx) {}
  43     bool Invoke(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam,
  44                 LRESULT* aResult);
  45     bool operator==(const CallbackData& rhs) const {
  46       return cb == rhs.cb && context == rhs.context;
  47     }
  48     bool operator!=(const CallbackData& rhs) const { return !(*this == rhs); }
  49     explicit operator bool() const { return !!cb; }
  50   };
  51
  52   typedef nsTArray<CallbackData> CallbackDataArray;
  53   struct MessageData {
  54     UINT nMsg;
  55     CallbackData hook;
  56     CallbackDataArray monitors;
  57   };
  58
  59   bool Notify(HWND hWnd, UINT nMsg, WPARAM wParam, LPARAM lParam,
  60               MSGResult& aResult);
  61
  62   MessageData* Lookup(UINT nMsg);
  63   MessageData* LookupOrCreate(UINT nMsg);
  64   void DeleteIfEmpty(MessageData* data);
  65
  66   typedef nsTArray<MessageData> MessageDataArray;
  67   MessageDataArray mMessageData;
  68
  69   // For Notify
  70   friend class ::nsWindow;
  71 };
  72
  73 }  // namespace widget
  74 }  // namespace mozilla
  75
  76 #endif  // __mozilla_WindowHook_h__