reactos/subsystems/win32/csrss/win32csr/desktopbg.c

   1 /* $Id$
   2  *
   3  * reactos/subsys/csrss/win32csr/desktopbg.c
   4  *
   5  * Desktop background window functions
   6  *
   7  * ReactOS Operating System
   8  */
   9
  10 #define NDEBUG
  11
  12 #include "w32csr.h"
  13 #include <debug.h>
  14
  15 #define DESKTOP_WINDOW_ATOM 32769
  16
  17 #define PM_SHOW_DESKTOP 1
  18 #define PM_HIDE_DESKTOP 2
  19
  20 typedef struct tagDTBG_THREAD_DATA
  21 {
  22     HDESK Desktop;
  23     HANDLE Event;
  24     NTSTATUS Status;
  25 } DTBG_THREAD_DATA, *PDTBG_THREAD_DATA;
  26
  27 typedef struct tagPRIVATE_NOTIFY_DESKTOP
  28 {
  29     NMHDR hdr;
  30     struct /* PM_SHOW_DESKTOP */
  31     {
  32         int Width;
  33         int Height;
  34     } ShowDesktop;
  35 } PRIVATE_NOTIFY_DESKTOP, *PPRIVATE_NOTIFY_DESKTOP;
  36
  37 static BOOL BgInitialized = FALSE;
  38 static HWND VisibleDesktopWindow = NULL;
  39
  40 static
  41 LRESULT
  42 CALLBACK
  43 DtbgWindowProc(HWND Wnd,
  44                UINT Msg,
  45                WPARAM wParam,
  46                LPARAM lParam)
  47 {
  48     PAINTSTRUCT PS;
  49
  50     switch (Msg)
  51     {
  52     case WM_ERASEBKGND:
  53         PaintDesktop((HDC)wParam);
  54         return 1;
  55
  56     case WM_PAINT:
  57         if (BeginPaint(Wnd, &PS))
  58             EndPaint(Wnd, &PS);
  59         return 0;
  60
  61     case WM_SETCURSOR:
  62         return (LRESULT)SetCursor(LoadCursorW(0, (LPCWSTR)IDC_ARROW));
  63
  64     case WM_NCCREATE:
  65         return (LRESULT)TRUE;
  66
  67     case WM_CREATE:
  68         NtUserSetWindowFNID(Wnd, FNID_DESKTOP); // Anti-ReactOS hack!
  69     case WM_CLOSE:
  70         return 0;
  71
  72     case WM_DISPLAYCHANGE:
  73         MoveWindow(Wnd, 0, 0, LOWORD(lParam), HIWORD(lParam), TRUE);
  74         break;
  75
  76     case WM_NOTIFY:
  77     {
  78         PPRIVATE_NOTIFY_DESKTOP nmh = (PPRIVATE_NOTIFY_DESKTOP)lParam;
  79
  80         /* Use WM_NOTIFY for private messages since
  81          * it can't be sent between processes!
  82          */
  83         switch (nmh->hdr.code)
  84         {
  85         case PM_SHOW_DESKTOP:
  86         {
  87             LRESULT Result;
  88
  89             Result = !SetWindowPos(Wnd, NULL, 0, 0,
  90                                    nmh->ShowDesktop.Width,
  91                                    nmh->ShowDesktop.Height,
  92                                    SWP_NOACTIVATE | SWP_NOZORDER |
  93                                    SWP_SHOWWINDOW);
  94
  95             UpdateWindow(Wnd);
  96             VisibleDesktopWindow = Wnd;
  97             return Result;
  98         }
  99
 100         case PM_HIDE_DESKTOP:
 101         {
 102             LRESULT Result;
 103
 104             Result = !SetWindowPos(Wnd, NULL, 0, 0, 0, 0,
 105                                    SWP_NOACTIVATE | SWP_NOZORDER |
 106                                    SWP_NOMOVE | SWP_NOSIZE | SWP_HIDEWINDOW);
 107
 108             UpdateWindow(Wnd);
 109             VisibleDesktopWindow = NULL;
 110             return Result;
 111         }
 112
 113         default:
 114             DPRINT("Unknown notification code 0x%x sent to the desktop window!\n",
 115                    nmh->hdr.code);
 116             return 0;
 117         }
 118     }
 119
 120     default:
 121         return DefWindowProcW(Wnd, Msg, wParam, lParam);
 122     }
 123
 124     return 0;
 125 }
 126
 127 static
 128 BOOL
 129 FASTCALL
 130 DtbgInit(VOID)
 131 {
 132     WNDCLASSEXW Class;
 133     ATOM ClassAtom;
 134
 135     /*
 136      * Create the desktop window class
 137      */
 138     Class.cbSize = sizeof(WNDCLASSEXW);
 139     Class.style = 0; // Local Class
 140     Class.lpfnWndProc = DtbgWindowProc;
 141     Class.cbClsExtra = 0;
 142     Class.cbWndExtra = 0;
 143     Class.hInstance = (HINSTANCE)GetModuleHandleW(NULL);
 144     Class.hIcon = NULL;
 145     Class.hCursor = NULL;
 146     Class.hbrBackground = GetSysColorBrush(COLOR_BACKGROUND);
 147     Class.lpszMenuName = NULL;
 148     Class.lpszClassName = (LPCWSTR)DESKTOP_WINDOW_ATOM;
 149     ClassAtom = RegisterClassExW(&Class);
 150
 151     if (ClassAtom == INVALID_ATOM)
 152     {
 153         DPRINT1("Unable to register desktop background class (error %d)\n",
 154                 GetLastError());
 155
 156         return FALSE;
 157     }
 158
 159     VisibleDesktopWindow = NULL;
 160
 161     return TRUE;
 162 }
 163
 164 static
 165 DWORD
 166 WINAPI
 167 DtbgDesktopThread(PVOID Data)
 168 {
 169     HWND BackgroundWnd;
 170     MSG msg;
 171     PDTBG_THREAD_DATA ThreadData = (PDTBG_THREAD_DATA)Data;
 172
 173     if (!SetThreadDesktop(ThreadData->Desktop))
 174     {
 175         DPRINT1("Failed to set thread desktop\n");
 176         ThreadData->Status = STATUS_UNSUCCESSFUL;
 177         SetEvent(ThreadData->Event);
 178         return 1;
 179     }
 180
 181     BackgroundWnd = CreateWindowW((LPCWSTR)DESKTOP_WINDOW_ATOM,
 182                                   L"",
 183                                   WS_POPUP | WS_CLIPCHILDREN,
 184                                   0, 0, 0, 0,
 185                                   NULL, NULL,
 186                                   (HINSTANCE)GetModuleHandleW(NULL),
 187                                   NULL);
 188
 189     if (NULL == BackgroundWnd)
 190     {
 191         DPRINT1("Failed to create desktop background window\n");
 192         ThreadData->Status = STATUS_UNSUCCESSFUL;
 193         SetEvent(ThreadData->Event);
 194         return 1;
 195     }
 196
 197     ThreadData->Status = STATUS_SUCCESS;
 198     SetEvent(ThreadData->Event);
 199
 200     while (GetMessageW(&msg, NULL, 0, 0))
 201     {
 202         TranslateMessage(&msg);
 203         DispatchMessageW(&msg);
 204     }
 205
 206     return 1;
 207 }
 208
 209 CSR_API(CsrCreateDesktop)
 210 {
 211     DTBG_THREAD_DATA ThreadData;
 212     HANDLE ThreadHandle;
 213
 214     DPRINT("CsrCreateDesktop\n");
 215
 216     Request->Header.u1.s1.TotalLength = sizeof(CSR_API_MESSAGE);
 217     Request->Header.u1.s1.DataLength = sizeof(CSR_API_MESSAGE) - sizeof(PORT_MESSAGE);
 218
 219     if (!BgInitialized)
 220     {
 221         BgInitialized = TRUE;
 222
 223         if (!DtbgInit())
 224             return STATUS_UNSUCCESSFUL;
 225     }
 226
 227     /*
 228      * The desktop handle we got from win32k is in
 229      * the scope of CSRSS so we can just use it.
 230      */
 231     ThreadData.Desktop = Request->Data.CreateDesktopRequest.DesktopHandle;
 232
 233     ThreadData.Event = CreateEventW(NULL, FALSE, FALSE, NULL);
 234
 235     if (NULL == ThreadData.Event)
 236     {
 237         DPRINT1("Failed to create event (error %d)\n", GetLastError());
 238         return STATUS_UNSUCCESSFUL;
 239     }
 240
 241     ThreadHandle = CreateThread(NULL,
 242                                 0,
 243                                 DtbgDesktopThread,
 244                                 (PVOID)&ThreadData,
 245                                 0,
 246                                 NULL);
 247
 248     if (NULL == ThreadHandle)
 249     {
 250         CloseHandle(ThreadData.Event);
 251         DPRINT1("Failed to create desktop window thread.\n");
 252         return STATUS_UNSUCCESSFUL;
 253     }
 254
 255     CloseHandle(ThreadHandle);
 256
 257     WaitForSingleObject(ThreadData.Event, INFINITE);
 258     CloseHandle(ThreadData.Event);
 259
 260     return ThreadData.Status;
 261 }
 262
 263 CSR_API(CsrShowDesktop)
 264 {
 265     PRIVATE_NOTIFY_DESKTOP nmh;
 266     DPRINT("CsrShowDesktop\n");
 267
 268     Request->Header.u1.s1.TotalLength = sizeof(CSR_API_MESSAGE);
 269     Request->Header.u1.s1.DataLength = sizeof(CSR_API_MESSAGE) - sizeof(PORT_MESSAGE);
 270
 271     nmh.hdr.hwndFrom = Request->Data.ShowDesktopRequest.DesktopWindow;
 272     nmh.hdr.idFrom = 0;
 273     nmh.hdr.code = PM_SHOW_DESKTOP;
 274
 275     nmh.ShowDesktop.Width = (int)Request->Data.ShowDesktopRequest.Width;
 276     nmh.ShowDesktop.Height = (int)Request->Data.ShowDesktopRequest.Height;
 277
 278     if (SendMessageW(Request->Data.ShowDesktopRequest.DesktopWindow,
 279                      WM_NOTIFY,
 280                      (WPARAM)nmh.hdr.hwndFrom,
 281                      (LPARAM)&nmh))
 282     {
 283         return STATUS_UNSUCCESSFUL;
 284     }
 285
 286     return STATUS_SUCCESS;
 287 }
 288
 289 CSR_API(CsrHideDesktop)
 290 {
 291     PRIVATE_NOTIFY_DESKTOP nmh;
 292     DPRINT("CsrHideDesktop\n");
 293
 294     Request->Header.u1.s1.TotalLength = sizeof(CSR_API_MESSAGE);
 295     Request->Header.u1.s1.DataLength = sizeof(CSR_API_MESSAGE) - sizeof(PORT_MESSAGE);
 296
 297     nmh.hdr.hwndFrom = Request->Data.ShowDesktopRequest.DesktopWindow;
 298     nmh.hdr.idFrom = 0;
 299     nmh.hdr.code = PM_HIDE_DESKTOP;
 300
 301     if (SendMessageW(Request->Data.ShowDesktopRequest.DesktopWindow,
 302                      WM_NOTIFY,
 303                      (WPARAM)nmh.hdr.hwndFrom,
 304                      (LPARAM)&nmh))
 305     {
 306         return STATUS_UNSUCCESSFUL;
 307     }
 308
 309     return STATUS_SUCCESS;
 310 }
 311
 312 BOOL
 313 FASTCALL
 314 DtbgIsDesktopVisible(VOID)
 315 {
 316     if (VisibleDesktopWindow != NULL &&
 317             !IsWindowVisible(VisibleDesktopWindow))
 318     {
 319         VisibleDesktopWindow = NULL;
 320     }
 321
 322     return VisibleDesktopWindow != NULL;
 323 }
 324
 325 /* EOF */