windows窗口消息内部处理机制

LRESULT WINAPI

RealDefWindowProcA(HWND hWnd,

                   UINT Msg,

                   WPARAM wParam,

                   LPARAM lParam)

{

    LRESULT Result &＃61; 0;

    PWND Wnd;



    //    spy&＃43;&＃43;的入口

    SPY_EnterMessage(SPY_DEFWNDPROC, hWnd, Msg, wParam, lParam);



    switch (Msg)

    {

        case WM_NCCREATE:

        {

            if (lParam)

            {

                LPCREATESTRUCTA cs &＃61; (LPCREATESTRUCTA)lParam;

                /* check for string, as static icons, bitmaps (SS_ICON, SS_BITMAP)

                 * may have child window IDs instead of window name */

                if (HIWORD(cs->lpszName))

                {

                    //    这个和setwindowtext是一样的, 只是将cs中的名字拷贝到窗口对象中的windowname而已

                    DefSetText(hWnd, (PCWSTR)cs->lpszName, TRUE);

                }

                Result &＃61; 1;

            }

            break;

        }



        case WM_GETTEXTLENGTH:

        {

            PWSTR buf;

            ULONG len;



            Wnd &＃61; ValidateHwnd(hWnd);

            if (Wnd !&＃61; NULL && Wnd->strName.Length !&＃61; 0)

            {

                buf &＃61; DesktopPtrToUser(Wnd->strName.Buffer);

                if (buf !&＃61; NULL &&

                    NT_SUCCESS(RtlUnicodeToMultiByteSize(&len,

                                                         buf,

                                                         Wnd->strName.Length)))

                {

                    Result &＃61; (LRESULT) len;

                }

            }

            else Result &＃61; 0L;



            break;

        }



        case WM_GETTEXT:

        {

            PWSTR buf &＃61; NULL;

            PSTR outbuf &＃61; (PSTR)lParam;

            UINT copy;



            Wnd &＃61; ValidateHwnd(hWnd);

            if (Wnd !&＃61; NULL && wParam !&＃61; 0)

            {

                if (Wnd->strName.Buffer !&＃61; NULL)

                    buf &＃61; DesktopPtrToUser(Wnd->strName.Buffer);

                else

                    outbuf[0] &＃61; L&＃39;\0&＃39;;



                if (buf !&＃61; NULL)

                {

                    if (Wnd->strName.Length !&＃61; 0)

                    {

                        copy &＃61; min(Wnd->strName.Length / sizeof(WCHAR), wParam - 1);

                        Result &＃61; WideCharToMultiByte(CP_ACP,

                                                     0,

                                                     buf,

                                                     copy,

                                                     outbuf,

                                                     wParam,

                                                     NULL,

                                                     NULL);

                        outbuf[Result] &＃61; &＃39;\0&＃39;;

                    }

                    else

                        outbuf[0] &＃61; &＃39;\0&＃39;;

                }

            }

            break;

        }



        case WM_SETTEXT:

        {

            DefSetText(hWnd, (PCWSTR)lParam, TRUE);



            if ((GetWindowLongPtrW(hWnd, GWL_STYLE) & WS_CAPTION) &＃61;&＃61; WS_CAPTION)

            {

                DefWndNCPaint(hWnd, HRGN_WINDOW, -1);

            }

            Result &＃61; 1;

            break;

        }



        case WM_IME_KEYDOWN:

        {

            Result &＃61; PostMessageA(hWnd, WM_KEYDOWN, wParam, lParam);

            break;

        }



        case WM_IME_KEYUP:

        {

            Result &＃61; PostMessageA(hWnd, WM_KEYUP, wParam, lParam);

            break;

        }



        case WM_IME_CHAR:

        {

            if (HIBYTE(wParam))

                PostMessageA(hWnd, WM_CHAR, HIBYTE(wParam), lParam);

            PostMessageA(hWnd, WM_CHAR, LOBYTE(wParam), lParam);

            break;

        }



        case WM_IME_STARTCOMPOSITION:

        case WM_IME_COMPOSITION:

        case WM_IME_ENDCOMPOSITION:

        case WM_IME_SELECT:

        case WM_IME_NOTIFY:

        {

            HWND hwndIME;



            hwndIME &＃61; DefWndImmGetDefaultIMEWnd(hWnd);

            if (hwndIME)

                Result &＃61; SendMessageA(hwndIME, Msg, wParam, lParam);

            break;

        }



        case WM_IME_SETCONTEXT:

        {

            HWND hwndIME;



            hwndIME &＃61; DefWndImmGetDefaultIMEWnd(hWnd);

            if (hwndIME)

                Result &＃61; DefWndImmIsUIMessageA(hwndIME, Msg, wParam, lParam);

            break;

        }



        /* fall through */

        default:

            Result &＃61; User32DefWindowProc(hWnd, Msg, wParam, lParam, FALSE);

    }



    SPY_ExitMessage(SPY_RESULT_DEFWND, hWnd, Msg, Result, wParam, lParam);

    return Result;

}

只要一深入到用户对象&＃xff0c; 就进入了win32k子系统层

windows消息定义 win32k层

static MSGMEMORY MsgMemory[] &＃61;
{
    { WM_CREATE, MMS_SIZE_SPECIAL, MMS_FLAG_READWRITE },
    { WM_DDE_ACK, sizeof(KMDDELPARAM), MMS_FLAG_READ },
    { WM_DDE_EXECUTE, MMS_SIZE_WPARAM, MMS_FLAG_READ },
    { WM_GETMINMAXINFO, sizeof(MINMAXINFO), MMS_FLAG_READWRITE },
    { WM_GETTEXT, MMS_SIZE_WPARAMWCHAR, MMS_FLAG_WRITE },
    { WM_NCCALCSIZE, MMS_SIZE_SPECIAL, MMS_FLAG_READWRITE },
    { WM_NCCREATE, MMS_SIZE_SPECIAL, MMS_FLAG_READWRITE },
    { WM_SETTEXT, MMS_SIZE_LPARAMSZ, MMS_FLAG_READ },
    { WM_STYLECHANGED, sizeof(STYLESTRUCT), MMS_FLAG_READ },
    { WM_STYLECHANGING, sizeof(STYLESTRUCT), MMS_FLAG_READWRITE },
    { WM_COPYDATA, MMS_SIZE_SPECIAL, MMS_FLAG_READ },
    { WM_COPYGLOBALDATA, MMS_SIZE_WPARAM, MMS_FLAG_READ },
    { WM_WINDOWPOSCHANGED, sizeof(WINDOWPOS), MMS_FLAG_READ },
    { WM_WINDOWPOSCHANGING, sizeof(WINDOWPOS), MMS_FLAG_READWRITE },
};