windows/dce.c

   1 /*
   2  * USER DCE functions
   3  *
   4  * Copyright 1993 Alexandre Julliard
   5  *           1996,1997 Alex Korobka
   6  *
   7  *
   8  * Note: Visible regions of CS_OWNDC/CS_CLASSDC window DCs
   9  * have to be updated dynamically.
  10  *
  11  * Internal DCX flags:
  12  *
  13  * DCX_DCEEMPTY    - dce is uninitialized
  14  * DCX_DCEBUSY     - dce is in use
  15  * DCX_DCEDIRTY    - ReleaseDC() should wipe instead of caching
  16  * DCX_KEEPCLIPRGN - ReleaseDC() should not delete the clipping region
  17  * DCX_WINDOWPAINT - BeginPaint() is in effect
  18  */
  19
  20 #include "options.h"
  21 #include "dce.h"
  22 #include "class.h"
  23 #include "win.h"
  24 #include "gdi.h"
  25 #include "region.h"
  26 #include "heap.h"
  27 #include "sysmetrics.h"
  28 #include "debug.h"
  29
  30 #define NB_DCE    5  /* Number of DCEs created at startup */
  31
  32 static DCE *firstDCE = 0;
  33 static HDC32 defaultDCstate = 0;
  34
  35 static void DCE_DeleteClipRgn( DCE* );
  36 static INT32 DCE_ReleaseDC( DCE* );
  37
  38
  39 /***********************************************************************
  40  *           DCE_DumpCache
  41  */
  42 static void DCE_DumpCache(void)
  43 {
  44     DCE* dce = firstDCE;
  45
  46     DUMP("DCE:\n");
  47     while( dce )
  48     {
  49         DUMP("\t[0x%08x] hWnd 0x%04x, dcx %08x, %s %s\n",
  50              (unsigned)dce, dce->hwndCurrent, (unsigned)dce->DCXflags,
  51              (dce->DCXflags & DCX_CACHE) ? "Cache" : "Owned",
  52              (dce->DCXflags & DCX_DCEBUSY) ? "InUse" : "" );
  53         dce = dce->next;
  54     }
  55 }
  56
  57 /***********************************************************************
  58  *           DCE_AllocDCE
  59  *
  60  * Allocate a new DCE.
  61  */
  62 DCE *DCE_AllocDCE( HWND32 hWnd, DCE_TYPE type )
  63 {
  64     DCE * dce;
  65     if (!(dce = HeapAlloc( SystemHeap, 0, sizeof(DCE) ))) return NULL;
  66     if (!(dce->hDC = CreateDC16( "DISPLAY", NULL, NULL, NULL )))
  67     {
  68         HeapFree( SystemHeap, 0, dce );
  69         return 0;
  70     }
  71
  72     /* store DCE handle in DC hook data field */
  73
  74     SetDCHook( dce->hDC, (FARPROC16)DCHook, (DWORD)dce );
  75
  76     dce->hwndCurrent = hWnd;
  77     dce->hClipRgn    = 0;
  78     dce->next        = firstDCE;
  79     firstDCE = dce;
  80
  81     if( type != DCE_CACHE_DC ) /* owned or class DC */
  82     {
  83         dce->DCXflags = DCX_DCEBUSY;
  84         if( hWnd )
  85         {
  86             WND* wnd = WIN_FindWndPtr(hWnd);
  87
  88             if( wnd->dwStyle & WS_CLIPCHILDREN ) dce->DCXflags |= DCX_CLIPCHILDREN;
  89             if( wnd->dwStyle & WS_CLIPSIBLINGS ) dce->DCXflags |= DCX_CLIPSIBLINGS;
  90         }
  91         SetHookFlags(dce->hDC,DCHF_INVALIDATEVISRGN);
  92     }
  93     else dce->DCXflags = DCX_CACHE | DCX_DCEEMPTY;
  94
  95     return dce;
  96 }
  97
  98
  99 /***********************************************************************
 100  *           DCE_FreeDCE
 101  */
 102 DCE* DCE_FreeDCE( DCE *dce )
 103 {
 104     DCE **ppDCE = &firstDCE;
 105
 106     if (!dce) return NULL;
 107     while (*ppDCE && (*ppDCE != dce)) ppDCE = &(*ppDCE)->next;
 108     if (*ppDCE == dce) *ppDCE = dce->next;
 109
 110     SetDCHook(dce->hDC, NULL, 0L);
 111
 112     DeleteDC32( dce->hDC );
 113     if( dce->hClipRgn && !(dce->DCXflags & DCX_KEEPCLIPRGN) )
 114         DeleteObject32(dce->hClipRgn);
 115     HeapFree( SystemHeap, 0, dce );
 116     return *ppDCE;
 117 }
 118
 119 /***********************************************************************
 120  *           DCE_FreeWindowDCE
 121  *
 122  * Remove owned DCE and reset unreleased cache DCEs.
 123  */
 124 void DCE_FreeWindowDCE( WND* pWnd )
 125 {
 126     DCE *pDCE = firstDCE;
 127
 128     while( pDCE )
 129     {
 130         if( pDCE->hwndCurrent == pWnd->hwndSelf )
 131         {
 132             if( pDCE == pWnd->dce ) /* owned DCE */
 133             {
 134                 pDCE = DCE_FreeDCE( pDCE );
 135                 pWnd->dce = NULL;
 136                 continue;
 137             }
 138             else
 139             {
 140                 if(!(pDCE->DCXflags & DCX_CACHE) ) /* class DCE */
 141                 {
 142                     if( pDCE->DCXflags & (DCX_INTERSECTRGN | DCX_EXCLUDERGN) )
 143                         DCE_DeleteClipRgn( pDCE );
 144                 }
 145                 else if( pDCE->DCXflags & DCX_DCEBUSY ) /* shared cache DCE */
 146                 {
 147                     ERR(dc,"[%04x] GetDC() without ReleaseDC()!\n",
 148                         pWnd->hwndSelf);
 149                     DCE_ReleaseDC( pDCE );
 150                 }
 151
 152                 pDCE->DCXflags &= DCX_CACHE;
 153                 pDCE->DCXflags |= DCX_DCEEMPTY;
 154                 pDCE->hwndCurrent = 0;
 155             }
 156         }
 157         pDCE = pDCE->next;
 158     }
 159 }
 160
 161
 162 /***********************************************************************
 163  *   DCE_DeleteClipRgn
 164  */
 165 static void DCE_DeleteClipRgn( DCE* dce )
 166 {
 167     dce->DCXflags &= ~(DCX_EXCLUDERGN | DCX_INTERSECTRGN | DCX_WINDOWPAINT);
 168
 169     if( dce->DCXflags & DCX_KEEPCLIPRGN )
 170         dce->DCXflags &= ~DCX_KEEPCLIPRGN;
 171     else
 172         if( dce->hClipRgn > 1 )
 173             DeleteObject32( dce->hClipRgn );
 174
 175     dce->hClipRgn = 0;
 176
 177     TRACE(dc,"\trestoring VisRgn\n");
 178
 179     RestoreVisRgn(dce->hDC);
 180 }
 181
 182
 183 /***********************************************************************
 184  *   DCE_ReleaseDC
 185  */
 186 static INT32 DCE_ReleaseDC( DCE* dce )
 187 {
 188     if ((dce->DCXflags & (DCX_DCEEMPTY | DCX_DCEBUSY)) != DCX_DCEBUSY) return 0;
 189
 190     /* restore previous visible region */
 191
 192     if ((dce->DCXflags & (DCX_INTERSECTRGN | DCX_EXCLUDERGN)) &&
 193         (dce->DCXflags & (DCX_CACHE | DCX_WINDOWPAINT)) )
 194         DCE_DeleteClipRgn( dce );
 195
 196     if (dce->DCXflags & DCX_CACHE)
 197     {
 198         SetDCState( dce->hDC, defaultDCstate );
 199         dce->DCXflags &= ~DCX_DCEBUSY;
 200         if (dce->DCXflags & DCX_DCEDIRTY)
 201         {
 202             /* don't keep around invalidated entries
 203              * because SetDCState() disables hVisRgn updates
 204              * by removing dirty bit. */
 205
 206             dce->hwndCurrent = 0;
 207             dce->DCXflags &= DCX_CACHE;
 208             dce->DCXflags |= DCX_DCEEMPTY;
 209         }
 210     }
 211     return 1;
 212 }
 213
 214
 215 /***********************************************************************
 216  *   DCE_InvalidateDCE
 217  *
 218  * It is called from SetWindowPos() - we have to mark as dirty all busy
 219  * DCE's for windows that have pWnd->parent as an ansector and whose client
 220  * rect intersects with specified update rectangle.
 221  */
 222 BOOL32 DCE_InvalidateDCE(WND* pWnd, const RECT32* pRectUpdate)
 223 {
 224     WND* wndScope = pWnd->parent;
 225     BOOL32 bRet = FALSE;
 226
 227     if( wndScope )
 228     {
 229         DCE *dce;
 230
 231         TRACE(dc,"scope hwnd = %04x, (%i,%i - %i,%i)\n",
 232                      wndScope->hwndSelf, pRectUpdate->left,pRectUpdate->top,
 233                      pRectUpdate->right,pRectUpdate->bottom);
 234         if(TRACE_ON(dc))
 235           DCE_DumpCache();
 236
 237         /* walk all DCEs and fixup non-empty entries */
 238
 239         for (dce = firstDCE; (dce); dce = dce->next)
 240         {
 241             if( !(dce->DCXflags & DCX_DCEEMPTY) )
 242             {
 243                 WND* wndCurrent = WIN_FindWndPtr(dce->hwndCurrent);
 244
 245                 if( wndCurrent && wndCurrent != WIN_GetDesktop() )
 246                 {
 247                     WND* wnd = wndCurrent;
 248                     INT32 xoffset = 0, yoffset = 0;
 249
 250                     if( (wndCurrent == wndScope) && !(dce->DCXflags & DCX_CLIPCHILDREN) ) continue;
 251
 252                     /* check if DCE window is within the z-order scope */
 253
 254                     for( wnd = wndCurrent; wnd; wnd = wnd->parent )
 255                     {
 256                         if( wnd == wndScope )
 257                         {
 258                             RECT32 wndRect;
 259
 260                             wndRect = wndCurrent->rectWindow;
 261
 262                             OffsetRect32( &wndRect, xoffset - wndCurrent->rectClient.left,
 263                                                     yoffset - wndCurrent->rectClient.top);
 264
 265                             if (pWnd == wndCurrent ||
 266                                 IntersectRect32( &wndRect, &wndRect, pRectUpdate ))
 267                             {
 268                                 if( !(dce->DCXflags & DCX_DCEBUSY) )
 269                                 {
 270                                     /* Don't bother with visible regions of unused DCEs */
 271
 272                                     TRACE(dc,"\tpurged %08x dce [%04x]\n",
 273                                                 (unsigned)dce, wndCurrent->hwndSelf);
 274
 275                                     dce->hwndCurrent = 0;
 276                                     dce->DCXflags &= DCX_CACHE;
 277                                     dce->DCXflags |= DCX_DCEEMPTY;
 278                                 }
 279                                 else
 280                                 {
 281                                     /* Set dirty bits in the hDC and DCE structs */
 282
 283                                     TRACE(dc,"\tfixed up %08x dce [%04x]\n",
 284                                                 (unsigned)dce, wndCurrent->hwndSelf);
 285
 286                                     dce->DCXflags |= DCX_DCEDIRTY;
 287                                     SetHookFlags(dce->hDC, DCHF_INVALIDATEVISRGN);
 288                                     bRet = TRUE;
 289                                 }
 290                             }
 291                             break;
 292                         }
 293                         xoffset += wnd->rectClient.left;
 294                         yoffset += wnd->rectClient.top;
 295                     }
 296                 }
 297             }
 298         } /* dce list */
 299     }
 300     return bRet;
 301 }
 302
 303 /***********************************************************************
 304  *           DCE_Init
 305  */
 306 void DCE_Init(void)
 307 {
 308     int i;
 309     DCE * dce;
 310
 311     for (i = 0; i < NB_DCE; i++)
 312     {
 313         if (!(dce = DCE_AllocDCE( 0, DCE_CACHE_DC ))) return;
 314         if (!defaultDCstate) defaultDCstate = GetDCState( dce->hDC );
 315     }
 316 }
 317
 318
 319 /***********************************************************************
 320  *           DCE_GetVisRect
 321  *
 322  * Calculate the visible rectangle of a window (i.e. the client or
 323  * window area clipped by the client area of all ancestors) in the
 324  * corresponding coordinates. Return FALSE if the visible region is empty.
 325  */
 326 static BOOL32 DCE_GetVisRect( WND *wndPtr, BOOL32 clientArea, RECT32 *lprect )
 327 {
 328     *lprect = clientArea ? wndPtr->rectClient : wndPtr->rectWindow;
 329
 330     if (wndPtr->dwStyle & WS_VISIBLE)
 331     {
 332         INT32 xoffset = lprect->left;
 333         INT32 yoffset = lprect->top;
 334
 335         while (wndPtr->parent)
 336         {
 337             wndPtr = wndPtr->parent;
 338
 339             if ( (wndPtr->dwStyle & (WS_ICONIC | WS_VISIBLE)) != WS_VISIBLE )
 340                 goto fail;
 341
 342             xoffset += wndPtr->rectClient.left;
 343             yoffset += wndPtr->rectClient.top;
 344             OffsetRect32( lprect, wndPtr->rectClient.left,
 345                                   wndPtr->rectClient.top );
 346
 347             if( (wndPtr->rectClient.left >= wndPtr->rectClient.right) ||
 348                 (wndPtr->rectClient.top >= wndPtr->rectClient.bottom) ||
 349                 (lprect->left >= wndPtr->rectClient.right) ||
 350                 (lprect->right <= wndPtr->rectClient.left) ||
 351                 (lprect->top >= wndPtr->rectClient.bottom) ||
 352                 (lprect->bottom <= wndPtr->rectClient.top) )
 353                 goto fail;
 354
 355             lprect->left = MAX( lprect->left, wndPtr->rectClient.left );
 356             lprect->right = MIN( lprect->right, wndPtr->rectClient.right );
 357             lprect->top = MAX( lprect->top, wndPtr->rectClient.top );
 358             lprect->bottom = MIN( lprect->bottom, wndPtr->rectClient.bottom );
 359         }
 360         OffsetRect32( lprect, -xoffset, -yoffset );
 361         return TRUE;
 362     }
 363
 364 fail:
 365     SetRectEmpty32( lprect );
 366     return FALSE;
 367 }
 368
 369
 370 /***********************************************************************
 371  *           DCE_AddClipRects
 372  *
 373  * Go through the linked list of windows from pWndStart to pWndEnd,
 374  * adding to the clip region the intersection of the target rectangle
 375  * with an offset window rectangle.
 376  */
 377 static BOOL32 DCE_AddClipRects( WND *pWndStart, WND *pWndEnd,
 378                                 HRGN32 hrgnClip, LPRECT32 lpRect, int x, int y )
 379 {
 380     RECT32 rect;
 381
 382     if (pWndStart->window) return TRUE; /* X itself will do the clipping */
 383
 384     for (; pWndStart != pWndEnd; pWndStart = pWndStart->next)
 385     {
 386         if( !(pWndStart->dwStyle & WS_VISIBLE) ) continue;
 387
 388         rect.left = pWndStart->rectWindow.left + x;
 389         rect.top = pWndStart->rectWindow.top + y;
 390         rect.right = pWndStart->rectWindow.right + x;
 391         rect.bottom = pWndStart->rectWindow.bottom + y;
 392
 393         if( IntersectRect32( &rect, &rect, lpRect ))
 394             if(!REGION_UnionRectWithRgn( hrgnClip, &rect ))
 395                 break;
 396     }
 397     return (pWndStart == pWndEnd);
 398 }
 399
 400
 401 /***********************************************************************
 402  *           DCE_GetVisRgn
 403  *
 404  * Return the visible region of a window, i.e. the client or window area
 405  * clipped by the client area of all ancestors, and then optionally
 406  * by siblings and children.
 407  */
 408 HRGN32 DCE_GetVisRgn( HWND32 hwnd, WORD flags )
 409 {
 410     HRGN32 hrgnVis = 0;
 411     RECT32 rect;
 412     WND *wndPtr = WIN_FindWndPtr( hwnd );
 413
 414     /* Get visible rectangle and create a region with it. */
 415
 416     if (wndPtr && DCE_GetVisRect(wndPtr, !(flags & DCX_WINDOW), &rect))
 417     {
 418         if((hrgnVis = CreateRectRgnIndirect32( &rect )))
 419         {
 420             HRGN32 hrgnClip = CreateRectRgn32( 0, 0, 0, 0 );
 421             INT32 xoffset, yoffset;
 422
 423             if( hrgnClip )
 424             {
 425                 /* Compute obscured region for the visible rectangle by
 426                  * clipping children, siblings, and ancestors. Note that
 427                  * DCE_GetVisRect() returns a rectangle either in client
 428                  * or in window coordinates (for DCX_WINDOW request). */
 429
 430                 if( (flags & DCX_CLIPCHILDREN) && wndPtr->child )
 431                 {
 432                     if( flags & DCX_WINDOW )
 433                     {
 434                         /* adjust offsets since child window rectangles are
 435                          * in client coordinates */
 436
 437                         xoffset = wndPtr->rectClient.left - wndPtr->rectWindow.left;
 438                         yoffset = wndPtr->rectClient.top - wndPtr->rectWindow.top;
 439                     }
 440                     else
 441                         xoffset = yoffset = 0;
 442
 443                     DCE_AddClipRects( wndPtr->child, NULL, hrgnClip,
 444                                       &rect, xoffset, yoffset );
 445                 }
 446
 447                 /* sibling window rectangles are in client
 448                  * coordinates of the parent window */
 449
 450                 if (flags & DCX_WINDOW)
 451                 {
 452                     xoffset = -wndPtr->rectWindow.left;
 453                     yoffset = -wndPtr->rectWindow.top;
 454                 }
 455                 else
 456                 {
 457                     xoffset = -wndPtr->rectClient.left;
 458                     yoffset = -wndPtr->rectClient.top;
 459                 }
 460
 461                 if (flags & DCX_CLIPSIBLINGS && wndPtr->parent )
 462                     DCE_AddClipRects( wndPtr->parent->child,
 463                                       wndPtr, hrgnClip, &rect, xoffset, yoffset );
 464
 465                 /* Clip siblings of all ancestors that have the
 466                  * WS_CLIPSIBLINGS style
 467                  */
 468
 469                 while (wndPtr->dwStyle & WS_CHILD)
 470                 {
 471                     wndPtr = wndPtr->parent;
 472                     xoffset -= wndPtr->rectClient.left;
 473                     yoffset -= wndPtr->rectClient.top;
 474                     if(wndPtr->dwStyle & WS_CLIPSIBLINGS && wndPtr->parent)
 475                     {
 476                         DCE_AddClipRects( wndPtr->parent->child, wndPtr,
 477                                           hrgnClip, &rect, xoffset, yoffset );
 478                     }
 479                 }
 480
 481                 /* Now once we've got a jumbo clip region we have
 482                  * to substract it from the visible rectangle.
 483                  */
 484
 485                 CombineRgn32( hrgnVis, hrgnVis, hrgnClip, RGN_DIFF );
 486                 DeleteObject32( hrgnClip );
 487             }
 488             else
 489             {
 490                 DeleteObject32( hrgnVis );
 491                 hrgnVis = 0;
 492             }
 493         }
 494     }
 495     else
 496         hrgnVis = CreateRectRgn32(0, 0, 0, 0); /* empty */
 497     return hrgnVis;
 498 }
 499
 500
 501 /***********************************************************************
 502  *           DCE_SetDrawable
 503  *
 504  * Set the drawable, origin and dimensions for the DC associated to
 505  * a given window.
 506  */
 507 static void DCE_SetDrawable( WND *wndPtr, DC *dc, WORD flags, BOOL32 bSetClipOrigin )
 508 {
 509     if (!wndPtr)  /* Get a DC for the whole screen */
 510     {
 511         dc->w.DCOrgX = 0;
 512         dc->w.DCOrgY = 0;
 513         dc->u.x.drawable = rootWindow;
 514         TSXSetSubwindowMode( display, dc->u.x.gc, IncludeInferiors );
 515     }
 516     else
 517     {
 518         if (flags & DCX_WINDOW)
 519         {
 520             dc->w.DCOrgX  = wndPtr->rectWindow.left;
 521             dc->w.DCOrgY  = wndPtr->rectWindow.top;
 522         }
 523         else
 524         {
 525             dc->w.DCOrgX  = wndPtr->rectClient.left;
 526             dc->w.DCOrgY  = wndPtr->rectClient.top;
 527         }
 528         while (!wndPtr->window)
 529         {
 530             wndPtr = wndPtr->parent;
 531             dc->w.DCOrgX += wndPtr->rectClient.left;
 532             dc->w.DCOrgY += wndPtr->rectClient.top;
 533         }
 534         dc->w.DCOrgX -= wndPtr->rectWindow.left;
 535         dc->w.DCOrgY -= wndPtr->rectWindow.top;
 536         dc->u.x.drawable = wndPtr->window;
 537
 538         /* This is needed when we reuse a cached DC because
 539          * SetDCState() called by ReleaseDC() screws up DC
 540          * origins for child windows.
 541          */
 542
 543         if( bSetClipOrigin )
 544             TSXSetClipOrigin( display, dc->u.x.gc, dc->w.DCOrgX, dc->w.DCOrgY );
 545     }
 546 }
 547 /***********************************************************************
 548  *           DCE_ExcludeRgn
 549  *
 550  *  Translate given region from the wnd client to the DC coordinates
 551  *  and add it to the clipping region.
 552  */
 553 INT16 DCE_ExcludeRgn( HDC32 hDC, WND* wnd, HRGN32 hRgn )
 554 {
 555   INT16    ret;
 556   POINT32  pt = {0, 0};
 557   HRGN32   hRgnClip = GetClipRgn16( hDC );
 558   DCE     *dce = firstDCE;
 559
 560   while (dce && (dce->hDC != hDC)) dce = dce->next;
 561   if( dce )
 562   {
 563       MapWindowPoints32( wnd->hwndSelf, dce->hwndCurrent, &pt, 1);
 564       if( dce->DCXflags & DCX_WINDOW )
 565       {
 566           wnd = WIN_FindWndPtr(dce->hwndCurrent);
 567           pt.x += wnd->rectClient.left - wnd->rectWindow.left;
 568           pt.y += wnd->rectClient.top - wnd->rectWindow.top;
 569       }
 570   }
 571   else return ERROR;
 572   OffsetRgn32(hRgn, pt.x, pt.y);
 573   if( hRgnClip ) ret = CombineRgn32( hRgnClip, hRgnClip, hRgn, RGN_DIFF );
 574   else
 575   {
 576       hRgnClip = InquireVisRgn( hDC );
 577       ret = CombineRgn32( hRgn, hRgnClip, hRgn, RGN_DIFF );
 578       SelectClipRgn32( hDC, hRgn );
 579   }
 580   return ret;
 581 }
 582
 583 /***********************************************************************
 584  *           GetDCEx16    (USER.359)
 585  */
 586 HDC16 WINAPI GetDCEx16( HWND16 hwnd, HRGN16 hrgnClip, DWORD flags )
 587 {
 588     return (HDC16)GetDCEx32( hwnd, hrgnClip, flags );
 589 }
 590
 591
 592 /***********************************************************************
 593  *           GetDCEx32    (USER32.231)
 594  *
 595  * Unimplemented flags: DCX_LOCKWINDOWUPDATE
 596  *
 597  * FIXME: Full support for hrgnClip == 1 (alias for entire window).
 598  */
 599 HDC32 WINAPI GetDCEx32( HWND32 hwnd, HRGN32 hrgnClip, DWORD flags )
 600 {
 601     HRGN32      hrgnVisible = 0;
 602     HDC32       hdc = 0;
 603     DCE *       dce;
 604     DC *        dc;
 605     WND *       wndPtr;
 606     DWORD       dcxFlags = 0;
 607     BOOL32      bUpdateVisRgn = TRUE;
 608     BOOL32      bUpdateClipOrigin = FALSE;
 609
 610     TRACE(dc,"hwnd %04x, hrgnClip %04x, flags %08x\n",
 611                                 hwnd, hrgnClip, (unsigned)flags);
 612
 613     if (!(wndPtr = WIN_FindWndPtr( hwnd ))) return 0;
 614
 615     /* fixup flags */
 616
 617     if (!(wndPtr->class->style & (CS_OWNDC | CS_CLASSDC))) flags |= DCX_CACHE;
 618
 619     if (flags & DCX_USESTYLE)
 620     {
 621         flags &= ~( DCX_CLIPCHILDREN | DCX_CLIPSIBLINGS | DCX_PARENTCLIP);
 622
 623         if( wndPtr->dwStyle & WS_CLIPSIBLINGS )
 624             flags |= DCX_CLIPSIBLINGS;
 625
 626         if ( !(flags & DCX_WINDOW) )
 627         {
 628             if (wndPtr->class->style & CS_PARENTDC) flags |= DCX_PARENTCLIP;
 629
 630             if (wndPtr->dwStyle & WS_CLIPCHILDREN &&
 631                      !(wndPtr->dwStyle & WS_MINIMIZE) ) flags |= DCX_CLIPCHILDREN;
 632         }
 633         else flags |= DCX_CACHE;
 634     }
 635
 636     if( flags & DCX_NOCLIPCHILDREN )
 637     {
 638         flags |= DCX_CACHE;
 639         flags &= ~(DCX_PARENTCLIP | DCX_CLIPCHILDREN);
 640     }
 641
 642     if (flags & DCX_WINDOW)
 643         flags = (flags & ~DCX_CLIPCHILDREN) | DCX_CACHE;
 644
 645     if (!(wndPtr->dwStyle & WS_CHILD) || !wndPtr->parent )
 646         flags &= ~DCX_PARENTCLIP;
 647     else if( flags & DCX_PARENTCLIP )
 648     {
 649         flags |= DCX_CACHE;
 650         if( !(flags & (DCX_CLIPSIBLINGS | DCX_CLIPCHILDREN)) )
 651             if( (wndPtr->dwStyle & WS_VISIBLE) && (wndPtr->parent->dwStyle & WS_VISIBLE) )
 652             {
 653                 flags &= ~DCX_CLIPCHILDREN;
 654                 if( wndPtr->parent->dwStyle & WS_CLIPSIBLINGS )
 655                     flags |= DCX_CLIPSIBLINGS;
 656             }
 657     }
 658
 659     /* find a suitable DCE */
 660
 661     dcxFlags = flags & (DCX_PARENTCLIP | DCX_CLIPSIBLINGS | DCX_CLIPCHILDREN |
 662                         DCX_CACHE | DCX_WINDOW);
 663
 664     if (flags & DCX_CACHE)
 665     {
 666         DCE*    dceEmpty;
 667         DCE*    dceUnused;
 668
 669         dceEmpty = dceUnused = NULL;
 670
 671         /* Strategy: First, we attempt to find a non-empty but unused DCE with
 672          * compatible flags. Next, we look for an empty entry. If the cache is
 673          * full we have to purge one of the unused entries.
 674          */
 675
 676         for (dce = firstDCE; (dce); dce = dce->next)
 677         {
 678             if ((dce->DCXflags & (DCX_CACHE | DCX_DCEBUSY)) == DCX_CACHE )
 679             {
 680                 dceUnused = dce;
 681
 682                 if (dce->DCXflags & DCX_DCEEMPTY)
 683                     dceEmpty = dce;
 684                 else
 685                 if ((dce->hwndCurrent == hwnd) &&
 686                    ((dce->DCXflags & (DCX_CLIPSIBLINGS | DCX_CLIPCHILDREN |
 687                                       DCX_CACHE | DCX_WINDOW | DCX_PARENTCLIP)) == dcxFlags))
 688                 {
 689                     TRACE(dc,"\tfound valid %08x dce [%04x], flags %08x\n",
 690                                         (unsigned)dce, hwnd, (unsigned)dcxFlags );
 691                     bUpdateVisRgn = FALSE;
 692                     bUpdateClipOrigin = TRUE;
 693                     break;
 694                 }
 695             }
 696         }
 697         if (!dce) dce = (dceEmpty) ? dceEmpty : dceUnused;
 698     }
 699     else
 700     {
 701         dce = (wndPtr->class->style & CS_OWNDC) ? wndPtr->dce : wndPtr->class->dce;
 702         if( dce->hwndCurrent == hwnd )
 703         {
 704             TRACE(dc,"\tskipping hVisRgn update\n");
 705             bUpdateVisRgn = FALSE; /* updated automatically, via DCHook() */
 706
 707             if( (dce->DCXflags & (DCX_EXCLUDERGN | DCX_INTERSECTRGN)) &&
 708                 (flags & (DCX_EXCLUDERGN | DCX_INTERSECTRGN)) )
 709             {
 710                 /* This is likely to be a nested BeginPaint(). */
 711
 712                 if( dce->hClipRgn != hrgnClip )
 713                 {
 714                     FIXME(dc,"new hrgnClip[%04x] smashes the previous[%04x]\n",
 715                           hrgnClip, dce->hClipRgn );
 716                     DCE_DeleteClipRgn( dce );
 717                 }
 718                 else
 719                     RestoreVisRgn(dce->hDC);
 720             }
 721         }
 722     }
 723     if (!dce) return 0;
 724
 725     dce->hwndCurrent = hwnd;
 726     dce->hClipRgn = 0;
 727     dce->DCXflags = dcxFlags | (flags & DCX_WINDOWPAINT) | DCX_DCEBUSY;
 728     hdc = dce->hDC;
 729
 730     if (!(dc = (DC *) GDI_GetObjPtr( hdc, DC_MAGIC ))) return 0;
 731     bUpdateVisRgn = bUpdateVisRgn || (dc->w.flags & DC_DIRTY);
 732
 733     /* recompute visible region */
 734
 735     DCE_SetDrawable( wndPtr, dc, flags, bUpdateClipOrigin );
 736     if( bUpdateVisRgn )
 737     {
 738         TRACE(dc,"updating visrgn for %08x dce, hwnd [%04x]\n", (unsigned)dce, hwnd);
 739
 740         if (flags & DCX_PARENTCLIP)
 741         {
 742             WND *parentPtr = wndPtr->parent;
 743
 744             if( wndPtr->dwStyle & WS_VISIBLE && !(parentPtr->dwStyle & WS_MINIMIZE) )
 745             {
 746                 if( parentPtr->dwStyle & WS_CLIPSIBLINGS )
 747                     dcxFlags = DCX_CLIPSIBLINGS | (flags & ~(DCX_CLIPCHILDREN | DCX_WINDOW));
 748                 else
 749                     dcxFlags = flags & ~(DCX_CLIPSIBLINGS | DCX_CLIPCHILDREN | DCX_WINDOW);
 750
 751                 hrgnVisible = DCE_GetVisRgn( parentPtr->hwndSelf, dcxFlags );
 752                 if( flags & DCX_WINDOW )
 753                     OffsetRgn32( hrgnVisible, -wndPtr->rectWindow.left,
 754                                               -wndPtr->rectWindow.top );
 755                 else
 756                     OffsetRgn32( hrgnVisible, -wndPtr->rectClient.left,
 757                                               -wndPtr->rectClient.top );
 758             }
 759             else
 760                 hrgnVisible = CreateRectRgn32( 0, 0, 0, 0 );
 761         }
 762         else
 763             if ((hwnd == GetDesktopWindow32()) &&
 764                 (rootWindow == DefaultRootWindow(display)))
 765                  hrgnVisible = CreateRectRgn32( 0, 0, SYSMETRICS_CXSCREEN,
 766                                                       SYSMETRICS_CYSCREEN );
 767             else hrgnVisible = DCE_GetVisRgn( hwnd, flags );
 768
 769         dc->w.flags &= ~DC_DIRTY;
 770         dce->DCXflags &= ~DCX_DCEDIRTY;
 771         SelectVisRgn( hdc, hrgnVisible );
 772     }
 773     else
 774         TRACE(dc,"no visrgn update %08x dce, hwnd [%04x]\n", (unsigned)dce, hwnd);
 775
 776     /* apply additional region operation (if any) */
 777
 778     if( flags & (DCX_EXCLUDERGN | DCX_INTERSECTRGN) )
 779     {
 780         if( !hrgnVisible ) hrgnVisible = CreateRectRgn32( 0, 0, 0, 0 );
 781
 782         dce->DCXflags |= flags & (DCX_KEEPCLIPRGN | DCX_INTERSECTRGN | DCX_EXCLUDERGN);
 783         dce->hClipRgn = hrgnClip;
 784
 785         TRACE(dc, "\tsaved VisRgn, clipRgn = %04x\n", hrgnClip);
 786
 787         SaveVisRgn( hdc );
 788         CombineRgn32( hrgnVisible, InquireVisRgn( hdc ), hrgnClip,
 789                       (flags & DCX_INTERSECTRGN) ? RGN_AND : RGN_DIFF );
 790         SelectVisRgn( hdc, hrgnVisible );
 791     }
 792
 793     if( hrgnVisible ) DeleteObject32( hrgnVisible );
 794
 795     TRACE(dc, "(%04x,%04x,0x%lx): returning %04x\n",
 796                hwnd, hrgnClip, flags, hdc);
 797     return hdc;
 798 }
 799
 800
 801 /***********************************************************************
 802  *           GetDC16    (USER.66)
 803  */
 804 HDC16 WINAPI GetDC16( HWND16 hwnd )
 805 {
 806     return (HDC16)GetDC32( hwnd );
 807 }
 808
 809
 810 /***********************************************************************
 811  *           GetDC32    (USER32.230)
 812  * RETURNS
 813  *      :Handle to DC
 814  *      NULL: Failure
 815  */
 816 HDC32 WINAPI GetDC32(
 817              HWND32 hwnd /* handle of window */
 818 ) {
 819     if (!hwnd)
 820         return GetDCEx32( GetDesktopWindow32(), 0, DCX_CACHE | DCX_WINDOW );
 821     return GetDCEx32( hwnd, 0, DCX_USESTYLE );
 822 }
 823
 824
 825 /***********************************************************************
 826  *           GetWindowDC16    (USER.67)
 827  */
 828 HDC16 WINAPI GetWindowDC16( HWND16 hwnd )
 829 {
 830     if (!hwnd) hwnd = GetDesktopWindow16();
 831     return GetDCEx16( hwnd, 0, DCX_USESTYLE | DCX_WINDOW );
 832 }
 833
 834
 835 /***********************************************************************
 836  *           GetWindowDC32    (USER32.304)
 837  */
 838 HDC32 WINAPI GetWindowDC32( HWND32 hwnd )
 839 {
 840     if (!hwnd) hwnd = GetDesktopWindow32();
 841     return GetDCEx32( hwnd, 0, DCX_USESTYLE | DCX_WINDOW );
 842 }
 843
 844
 845 /***********************************************************************
 846  *           ReleaseDC16    (USER.68)
 847  */
 848 INT16 WINAPI ReleaseDC16( HWND16 hwnd, HDC16 hdc )
 849 {
 850     return (INT16)ReleaseDC32( hwnd, hdc );
 851 }
 852
 853
 854 /***********************************************************************
 855  *           ReleaseDC32    (USER32.440)
 856  *
 857  * RETURNS
 858  *      1: Success
 859  *      0: Failure
 860  */
 861 INT32 WINAPI ReleaseDC32(
 862              HWND32 hwnd /* Handle of window - ignored */,
 863              HDC32 hdc   /* Handle of device context */
 864 ) {
 865     DCE * dce = firstDCE;
 866
 867     TRACE(dc, "%04x %04x\n", hwnd, hdc );
 868
 869     while (dce && (dce->hDC != hdc)) dce = dce->next;
 870
 871     if ( dce )
 872         if ( dce->DCXflags & DCX_DCEBUSY )
 873              return DCE_ReleaseDC( dce );
 874     return 0;
 875 }
 876
 877 /***********************************************************************
 878  *           DCHook    (USER.362)
 879  *
 880  * See "Undoc. Windows" for hints (DC, SetDCHook, SetHookFlags)..
 881  */
 882 BOOL16 WINAPI DCHook( HDC16 hDC, WORD code, DWORD data, LPARAM lParam )
 883 {
 884     HRGN32 hVisRgn;
 885     DCE *dce = firstDCE;;
 886
 887     TRACE(dc,"hDC = %04x, %i\n", hDC, code);
 888
 889     while (dce && (dce->hDC != hDC)) dce = dce->next;
 890     if (!dce) return 0;
 891
 892     switch( code )
 893     {
 894       case DCHC_INVALIDVISRGN:
 895
 896            /* GDI code calls this when it detects that the
 897             * DC is dirty (usually after SetHookFlags()). This
 898             * means that we have to recompute the visible region.
 899             */
 900
 901            if( dce->DCXflags & DCX_DCEBUSY )
 902            {
 903                SetHookFlags(hDC, DCHF_VALIDATEVISRGN);
 904                hVisRgn = DCE_GetVisRgn(dce->hwndCurrent, dce->DCXflags);
 905
 906                TRACE(dc,"\tapplying saved clipRgn\n");
 907
 908                /* clip this region with saved clipping region */
 909
 910                if ( (dce->DCXflags & DCX_INTERSECTRGN && dce->hClipRgn != 1) ||
 911                   (  dce->DCXflags & DCX_EXCLUDERGN && dce->hClipRgn) )
 912                {
 913
 914                     if( (!dce->hClipRgn && dce->DCXflags & DCX_INTERSECTRGN) ||
 915                          (dce->hClipRgn == 1 && dce->DCXflags & DCX_EXCLUDERGN) )
 916                          SetRectRgn32(hVisRgn,0,0,0,0);
 917                     else
 918                          CombineRgn32(hVisRgn, hVisRgn, dce->hClipRgn,
 919                                       (dce->DCXflags & DCX_EXCLUDERGN)? RGN_DIFF:RGN_AND);
 920                }
 921                dce->DCXflags &= ~DCX_DCEDIRTY;
 922                SelectVisRgn(hDC, hVisRgn);
 923                DeleteObject32( hVisRgn );
 924            }
 925            else /* non-fatal but shouldn't happen */
 926              WARN(dc, "DC is not in use!\n");
 927            break;
 928
 929       case DCHC_DELETEDC: /* FIXME: ?? */
 930            break;
 931
 932       default:
 933            FIXME(dc,"unknown code\n");
 934     }
 935   return 0;
 936 }
 937
 938
 939 /**********************************************************************
 940  *          WindowFromDC16   (USER.117)
 941  */
 942 HWND16 WINAPI WindowFromDC16( HDC16 hDC )
 943 {
 944     return (HWND16)WindowFromDC32( hDC );
 945 }
 946
 947
 948 /**********************************************************************
 949  *          WindowFromDC32   (USER32.581)
 950  */
 951 HWND32 WINAPI WindowFromDC32( HDC32 hDC )
 952 {
 953     DCE *dce = firstDCE;
 954     while (dce && (dce->hDC != hDC)) dce = dce->next;
 955     return dce ? dce->hwndCurrent : 0;
 956 }
 957
 958
 959 /***********************************************************************
 960  *           LockWindowUpdate16   (USER.294)
 961  */
 962 BOOL16 WINAPI LockWindowUpdate16( HWND16 hwnd )
 963 {
 964     return LockWindowUpdate32( hwnd );
 965 }
 966
 967
 968 /***********************************************************************
 969  *           LockWindowUpdate32   (USER32.378)
 970  */
 971 BOOL32 WINAPI LockWindowUpdate32( HWND32 hwnd )
 972 {
 973     /* FIXME? DCX_LOCKWINDOWUPDATE is unimplemented */
 974     return TRUE;
 975 }