reactos/win32ss/user/ntuser/monitor.c

   1 /*
   2  *  COPYRIGHT:        See COPYING in the top level directory
   3  *  PROJECT:          ReactOS kernel
   4  *  PURPOSE:          pMonitor support
   5  *  FILE:             subsys/win32k/ntuser/monitor.c
   6  *  PROGRAMERS:       Anich Gregor (blight@blight.eu.org)
   7  *                    Rafal Harabien (rafalh@reactos.org)
   8  */
   9
  10 #include <win32k.h>
  11 DBG_DEFAULT_CHANNEL(UserMonitor);
  12
  13 #define NDEBUG
  14 #include <debug.h>
  15
  16 /* GLOBALS *******************************************************************/
  17
  18 /* List of monitors */
  19 static PMONITOR gMonitorList = NULL;
  20
  21 /* PRIVATE FUNCTIONS **********************************************************/
  22
  23 /* IntCreateMonitorObject
  24  *
  25  * Creates a MONITOR
  26  *
  27  * Return value
  28  *   If the function succeeds a pointer to a MONITOR is returned. On failure
  29  *   NULL is returned.
  30  */
  31 static
  32 PMONITOR
  33 IntCreateMonitorObject()
  34 {
  35     return UserCreateObject(gHandleTable, NULL, NULL, NULL, TYPE_MONITOR, sizeof(MONITOR));
  36 }
  37
  38 /* IntDestroyMonitorObject
  39  *
  40  * Destroys a MONITOR
  41  * You have to be the owner of the monitors lock to safely destroy it.
  42  *
  43  * Arguments
  44  *
  45  *   pMonitor
  46  *      Pointer to the MONITOR which shall be deleted
  47  */
  48 static
  49 void
  50 IntDestroyMonitorObject(IN PMONITOR pMonitor)
  51 {
  52     /* Remove monitor region */
  53     if (pMonitor->hrgnMonitor)
  54     {
  55         GreSetObjectOwner(pMonitor->hrgnMonitor, GDI_OBJ_HMGR_POWNED);
  56         GreDeleteObject(pMonitor->hrgnMonitor);
  57     }
  58
  59     /* Destroy monitor object */
  60     UserDereferenceObject(pMonitor);
  61     UserDeleteObject(UserHMGetHandle(pMonitor), TYPE_MONITOR);
  62 }
  63
  64 /* UserGetMonitorObject
  65  *
  66  * Returns monitor object from handle or sets last error if handle is invalid
  67  *
  68  * Arguments
  69  *
  70  *   hMonitor
  71  *      Handle of MONITOR object
  72  */
  73 PMONITOR NTAPI
  74 UserGetMonitorObject(IN HMONITOR hMonitor)
  75 {
  76     PMONITOR pMonitor;
  77
  78     if (!hMonitor)
  79     {
  80         EngSetLastError(ERROR_INVALID_MONITOR_HANDLE);
  81         return NULL;
  82     }
  83
  84     pMonitor = (PMONITOR)UserGetObject(gHandleTable, hMonitor, TYPE_MONITOR);
  85     if (!pMonitor)
  86     {
  87         EngSetLastError(ERROR_INVALID_MONITOR_HANDLE);
  88         return NULL;
  89     }
  90
  91     return pMonitor;
  92 }
  93
  94 /* UserGetPrimaryMonitor
  95  *
  96  * Returns a PMONITOR for the primary monitor
  97  *
  98  * Return value
  99  *   PMONITOR
 100  */
 101 PMONITOR NTAPI
 102 UserGetPrimaryMonitor()
 103 {
 104     PMONITOR pMonitor;
 105
 106     /* Find primary monitor */
 107     for (pMonitor = gMonitorList; pMonitor != NULL; pMonitor = pMonitor->pMonitorNext)
 108     {
 109         if (pMonitor->IsPrimary)
 110             break;
 111     }
 112
 113     return pMonitor;
 114 }
 115
 116 /* UserAttachMonitor
 117  *
 118  * Creates a new MONITOR and appends it to the list of monitors.
 119  *
 120  * Arguments
 121  *
 122  *   pGdiDevice     Pointer to the PDEVOBJ onto which the monitor was attached
 123  *   DisplayNumber  Display Number (starting with 0)
 124  *
 125  * Return value
 126  *   Returns a NTSTATUS
 127  */
 128 NTSTATUS NTAPI
 129 UserAttachMonitor(IN HDEV hDev)
 130 {
 131     PMONITOR pMonitor;
 132
 133     TRACE("Attaching monitor...\n");
 134
 135     /* Create new monitor object */
 136     pMonitor = IntCreateMonitorObject();
 137     if (pMonitor == NULL)
 138     {
 139         TRACE("Couldnt create monitor object\n");
 140         return STATUS_INSUFFICIENT_RESOURCES;
 141     }
 142
 143     pMonitor->hDev = hDev;
 144     pMonitor->cWndStack = 0;
 145
 146     if (gMonitorList == NULL)
 147     {
 148         TRACE("Primary monitor is beeing attached\n");
 149         pMonitor->IsPrimary = TRUE;
 150         gMonitorList = pMonitor;
 151     }
 152     else
 153     {
 154         PMONITOR pmonLast = gMonitorList;
 155         TRACE("Additional monitor is beeing attached\n");
 156         while (pmonLast->pMonitorNext != NULL)
 157             pmonLast = pmonLast->pMonitorNext;
 158
 159         pmonLast->pMonitorNext = pMonitor;
 160     }
 161
 162     UserUpdateMonitorSize(hDev);
 163
 164     return STATUS_SUCCESS;
 165 }
 166
 167 /* UserDetachMonitor
 168  *
 169  * Deletes a MONITOR and removes it from the list of monitors.
 170  *
 171  * Arguments
 172  *
 173  *   pGdiDevice  Pointer to the PDEVOBJ from which the monitor was detached
 174  *
 175  * Return value
 176  *   Returns a NTSTATUS
 177  */
 178 NTSTATUS NTAPI
 179 UserDetachMonitor(IN HDEV hDev)
 180 {
 181     PMONITOR pMonitor = gMonitorList, *pLink = &gMonitorList;
 182
 183     /* Find monitor attached to given device */
 184     while (pMonitor != NULL)
 185     {
 186         if (pMonitor->hDev == hDev)
 187             break;
 188
 189         pLink = &pMonitor->pMonitorNext;
 190         pMonitor = pMonitor->pMonitorNext;
 191     }
 192
 193     if (pMonitor == NULL)
 194     {
 195         /* No monitor has been found */
 196         return STATUS_INVALID_PARAMETER;
 197     }
 198
 199     /* We destroy primary monitor - set next as primary */
 200     if (pMonitor->IsPrimary && pMonitor->pMonitorNext != NULL)
 201         pMonitor->pMonitorNext->IsPrimary = TRUE;
 202
 203     /* Update Next ptr in previous monitor */
 204     *pLink = pMonitor->pMonitorNext;
 205
 206     /* Finally destroy monitor */
 207     IntDestroyMonitorObject(pMonitor);
 208
 209     return STATUS_SUCCESS;
 210 }
 211
 212 /* UserUpdateMonitorSize
 213  *
 214  * Reset size of the monitor using atached device
 215  *
 216  * Arguments
 217  *
 218  *   PMONITOR
 219  *      pGdiDevice  Pointer to the PDEVOBJ, which size has changed
 220  *
 221  * Return value
 222  *   Returns a NTSTATUS
 223  */
 224 NTSTATUS NTAPI
 225 UserUpdateMonitorSize(IN HDEV hDev)
 226 {
 227         PMONITOR pMonitor;
 228     SIZEL DeviceSize;
 229
 230     /* Find monitor attached to given device */
 231     for (pMonitor = gMonitorList; pMonitor != NULL; pMonitor = pMonitor->pMonitorNext)
 232     {
 233         if (pMonitor->hDev == hDev)
 234             break;
 235     }
 236
 237     if (pMonitor == NULL)
 238     {
 239         /* No monitor has been found */
 240         return STATUS_INVALID_PARAMETER;
 241     }
 242
 243     /* Get the size of the hdev */
 244     PDEVOBJ_sizl((PPDEVOBJ)hDev, &DeviceSize);
 245
 246     /* Update monitor size */
 247     pMonitor->rcMonitor.left  = 0;
 248     pMonitor->rcMonitor.top   = 0;
 249     pMonitor->rcMonitor.right  = pMonitor->rcMonitor.left + DeviceSize.cx;
 250     pMonitor->rcMonitor.bottom = pMonitor->rcMonitor.top + DeviceSize.cy;
 251     pMonitor->rcWork = pMonitor->rcMonitor;
 252
 253     /* Destroy monitor region... */
 254     if (pMonitor->hrgnMonitor)
 255     {
 256         GreSetObjectOwner(pMonitor->hrgnMonitor, GDI_OBJ_HMGR_POWNED);
 257         GreDeleteObject(pMonitor->hrgnMonitor);
 258     }
 259
 260     /* ...and create new one */
 261     pMonitor->hrgnMonitor = IntSysCreateRectRgnIndirect(&pMonitor->rcMonitor);
 262     if (pMonitor->hrgnMonitor)
 263         IntGdiSetRegionOwner(pMonitor->hrgnMonitor, GDI_OBJ_HMGR_PUBLIC);
 264
 265     return STATUS_SUCCESS;
 266 }
 267
 268 /* IntGetMonitorsFromRect
 269  *
 270  * Returns a list of monitor handles/rectangles. The rectangles in the list are
 271  * the areas of intersection with the monitors.
 272  *
 273  * Arguments
 274  *
 275  *   pRect
 276  *      Rectangle in desktop coordinates. If this is NULL all monitors are
 277  *      returned and the rect list is filled with the sizes of the monitors.
 278  *
 279  *   phMonitorList
 280  *      Pointer to an array of HMONITOR which is filled with monitor handles.
 281  *      Can be NULL
 282  *
 283  *   prcMonitorList
 284  *      Pointer to an array of RECT which is filled with intersection rects in
 285  *      desktop coordinates.
 286  *      Can be NULL, will be ignored if no intersecting monitor is found and
 287  *      flags is MONITOR_DEFAULTTONEAREST
 288  *
 289  *   dwListSize
 290  *      Size of the phMonitorList and prcMonitorList arguments. If this is zero
 291  *      phMonitorList and prcMonitorList are ignored.
 292  *
 293  *   dwFlags
 294  *      Either 0 or MONITOR_DEFAULTTONEAREST (ignored if rect is NULL)
 295  *
 296  * Returns
 297  *   The number of monitors which intersect the specified region.
 298  */
 299 static
 300 UINT
 301 IntGetMonitorsFromRect(OPTIONAL IN LPCRECTL pRect,
 302                        OPTIONAL OUT HMONITOR *phMonitorList,
 303                        OPTIONAL OUT PRECTL prcMonitorList,
 304                        OPTIONAL IN DWORD dwListSize,
 305                        OPTIONAL IN DWORD dwFlags)
 306 {
 307     PMONITOR pMonitor, pNearestMonitor = NULL, pPrimaryMonitor = NULL;
 308     UINT cMonitors = 0;
 309     ULONG iNearestDistance = 0xffffffff;
 310
 311     /* Find monitors which intersects the rectangle */
 312     for (pMonitor = gMonitorList; pMonitor != NULL; pMonitor = pMonitor->pMonitorNext)
 313     {
 314         RECTL MonitorRect, IntersectionRect;
 315
 316         MonitorRect = pMonitor->rcMonitor;
 317
 318         TRACE("MonitorRect: left = %d, top = %d, right = %d, bottom = %d\n",
 319                MonitorRect.left, MonitorRect.top, MonitorRect.right, MonitorRect.bottom);
 320
 321         /* Save primary monitor for later usage */
 322         if (dwFlags == MONITOR_DEFAULTTOPRIMARY && pMonitor->IsPrimary)
 323             pPrimaryMonitor = pMonitor;
 324
 325         /* Check if a rect is given */
 326         if (pRect == NULL)
 327         {
 328             /* No rect given, so use the full monitor rect */
 329             IntersectionRect = MonitorRect;
 330         }
 331         /* We have a rect, calculate intersection */
 332         else if (!RECTL_bIntersectRect(&IntersectionRect, &MonitorRect, pRect))
 333         {
 334             /* Rects did not intersect */
 335             if (dwFlags == MONITOR_DEFAULTTONEAREST)
 336             {
 337                 ULONG cx, cy, iDistance;
 338
 339                 /* Get x and y distance */
 340                 cx = min(abs(MonitorRect.left - pRect->right),
 341                          abs(pRect->left - MonitorRect.right));
 342                 cy = min(abs(MonitorRect.top - pRect->bottom),
 343                          abs(pRect->top - MonitorRect.bottom));
 344
 345                 /* Calculate distance square */
 346                 iDistance = cx * cx + cy * cy;
 347
 348                 /* Check if this is the new nearest monitor */
 349                 if (iDistance < iNearestDistance)
 350                 {
 351                     iNearestDistance = iDistance;
 352                     pNearestMonitor = pMonitor;
 353                 }
 354             }
 355
 356             continue;
 357         }
 358
 359         /* Check if there's space in the buffer */
 360         if (cMonitors < dwListSize)
 361         {
 362             /* Save monitor data */
 363             if (phMonitorList != NULL)
 364                 phMonitorList[cMonitors] = UserHMGetHandle(pMonitor);
 365             if (prcMonitorList != NULL)
 366                 prcMonitorList[cMonitors] = IntersectionRect;
 367         }
 368
 369         /* Increase count of found monitors */
 370         cMonitors++;
 371     }
 372
 373     /* Nothing has been found? */
 374     if (cMonitors == 0)
 375     {
 376         /* Check if we shall default to the nearest monitor */
 377         if (dwFlags == MONITOR_DEFAULTTONEAREST && pNearestMonitor)
 378         {
 379             if (phMonitorList && dwListSize > 0)
 380                 phMonitorList[cMonitors] = UserHMGetHandle(pNearestMonitor);
 381             cMonitors++;
 382         }
 383         /* Check if we shall default to the primary monitor */
 384         else if (dwFlags == MONITOR_DEFAULTTOPRIMARY && pPrimaryMonitor)
 385         {
 386             if (phMonitorList != NULL && dwListSize > 0)
 387                 phMonitorList[cMonitors] = UserHMGetHandle(pPrimaryMonitor);
 388             cMonitors++;
 389         }
 390     }
 391
 392     return cMonitors;
 393 }
 394
 395 PMONITOR NTAPI
 396 UserMonitorFromRect(
 397     PRECTL pRect,
 398     DWORD dwFlags)
 399 {
 400     ULONG cMonitors, LargestArea = 0, i;
 401     PRECTL prcMonitorList = NULL;
 402     HMONITOR *phMonitorList = NULL;
 403     HMONITOR hMonitor = NULL;
 404
 405     /* Check if flags are valid */
 406     if (dwFlags != MONITOR_DEFAULTTONULL &&
 407         dwFlags != MONITOR_DEFAULTTOPRIMARY &&
 408         dwFlags != MONITOR_DEFAULTTONEAREST)
 409     {
 410         EngSetLastError(ERROR_INVALID_FLAGS);
 411         return NULL;
 412     }
 413
 414     /* Find intersecting monitors */
 415     cMonitors = IntGetMonitorsFromRect(pRect, &hMonitor, NULL, 1, dwFlags);
 416     if (cMonitors <= 1)
 417     {
 418         /* No or one monitor found. Just return handle. */
 419         goto cleanup;
 420     }
 421
 422     /* There is more than one monitor. Find monitor with largest intersection.
 423        Temporary reset hMonitor */
 424     hMonitor = NULL;
 425
 426     /* Allocate helper buffers */
 427     phMonitorList = ExAllocatePoolWithTag(PagedPool,
 428                                           sizeof(HMONITOR) * cMonitors,
 429                                           USERTAG_MONITORRECTS);
 430     if (phMonitorList == NULL)
 431     {
 432         EngSetLastError(ERROR_NOT_ENOUGH_MEMORY);
 433         goto cleanup;
 434     }
 435
 436     prcMonitorList = ExAllocatePoolWithTag(PagedPool,
 437                                            sizeof(RECT) * cMonitors,
 438                                            USERTAG_MONITORRECTS);
 439     if (prcMonitorList == NULL)
 440     {
 441         EngSetLastError(ERROR_NOT_ENOUGH_MEMORY);
 442         goto cleanup;
 443     }
 444
 445     /* Get intersecting monitors again but now with rectangle list */
 446     cMonitors = IntGetMonitorsFromRect(pRect, phMonitorList, prcMonitorList,
 447                                        cMonitors, 0);
 448
 449     /* Find largest intersection */
 450     for (i = 0; i < cMonitors; i++)
 451     {
 452         ULONG Area = (prcMonitorList[i].right - prcMonitorList[i].left) *
 453                      (prcMonitorList[i].bottom - prcMonitorList[i].top);
 454         if (Area >= LargestArea)
 455         {
 456             hMonitor = phMonitorList[i];
 457             LargestArea = Area;
 458         }
 459     }
 460
 461 cleanup:
 462     if (phMonitorList)
 463         ExFreePoolWithTag(phMonitorList, USERTAG_MONITORRECTS);
 464     if (prcMonitorList)
 465         ExFreePoolWithTag(prcMonitorList, USERTAG_MONITORRECTS);
 466
 467     return UserGetMonitorObject(hMonitor);
 468 }
 469
 470
 471 /* PUBLIC FUNCTIONS ***********************************************************/
 472
 473 /* NtUserEnumDisplayMonitors
 474  *
 475  * Enumerates display monitors which intersect the given HDC/cliprect
 476  *
 477  * Arguments
 478  *
 479  *   hdc
 480  *      Handle to a DC for which to enum intersecting monitors. If this is NULL
 481  *      it returns all monitors which are part of the current virtual screen.
 482  *
 483  *   pUnsafeRect
 484  *      Clipping rectangle with coordinate system origin at the DCs origin if the
 485  *      given HDC is not NULL or in virtual screen coordinated if it is NULL.
 486  *      Can be NULL
 487  *
 488  *   phUnsafeMonitorList
 489  *      Pointer to an array of HMONITOR which is filled with monitor handles.
 490  *      Can be NULL
 491  *
 492  *   prcUnsafeMonitorList
 493  *      Pointer to an array of RECT which is filled with intersection rectangles.
 494  *      Can be NULL
 495  *
 496  *   dwListSize
 497  *      Size of the hMonitorList and monitorRectList arguments. If this is zero
 498  *      hMonitorList and monitorRectList are ignored.
 499  *
 500  * Returns
 501  *   The number of monitors which intersect the specified region or -1 on failure.
 502  */
 503 INT
 504 APIENTRY
 505 NtUserEnumDisplayMonitors(
 506     OPTIONAL IN HDC hdc,
 507     OPTIONAL IN LPCRECTL pUnsafeRect,
 508     OPTIONAL OUT HMONITOR *phUnsafeMonitorList,
 509     OPTIONAL OUT PRECTL prcUnsafeMonitorList,
 510     OPTIONAL IN DWORD dwListSize)
 511 {
 512     INT cMonitors, iRet = -1, i;
 513     HMONITOR *phMonitorList = NULL;
 514     PRECTL prcMonitorList = NULL;
 515     RECTL rc, *pRect;
 516     RECTL DcRect = {0};
 517     NTSTATUS Status;
 518
 519     /* Get rectangle */
 520     if (pUnsafeRect != NULL)
 521     {
 522         Status = MmCopyFromCaller(&rc, pUnsafeRect, sizeof(RECT));
 523         if (!NT_SUCCESS(Status))
 524         {
 525             TRACE("MmCopyFromCaller() failed!\n");
 526             SetLastNtError(Status);
 527             return -1;
 528         }
 529     }
 530
 531     if (hdc != NULL)
 532     {
 533         PDC pDc;
 534         INT iRgnType;
 535
 536         /* Get visible region bounding rect */
 537         pDc = DC_LockDc(hdc);
 538         if (pDc == NULL)
 539         {
 540             TRACE("DC_LockDc() failed!\n");
 541             /* FIXME: setlasterror? */
 542             return -1;
 543         }
 544         iRgnType = REGION_GetRgnBox(pDc->prgnVis, &DcRect);
 545         DC_UnlockDc(pDc);
 546
 547         if (iRgnType == 0)
 548         {
 549             TRACE("NtGdiGetRgnBox() failed!\n");
 550             return -1;
 551         }
 552         if (iRgnType == NULLREGION)
 553             return 0;
 554         if (iRgnType == COMPLEXREGION)
 555         {
 556             /* TODO: Warning */
 557         }
 558
 559         /* If hdc and pRect are given the area of interest is pRect with
 560            coordinate origin at the DC position */
 561         if (pUnsafeRect != NULL)
 562         {
 563             rc.left += DcRect.left;
 564             rc.right += DcRect.left;
 565             rc.top += DcRect.top;
 566             rc.bottom += DcRect.top;
 567         }
 568         /* If hdc is given and pRect is not the area of interest is the
 569            bounding rect of hdc */
 570         else
 571         {
 572             rc = DcRect;
 573         }
 574     }
 575
 576     if (hdc == NULL && pUnsafeRect == NULL)
 577         pRect = NULL;
 578     else
 579         pRect = &rc;
 580
 581     UserEnterShared();
 582
 583     /* Find intersecting monitors */
 584     cMonitors = IntGetMonitorsFromRect(pRect, NULL, NULL, 0, MONITOR_DEFAULTTONULL);
 585     if (cMonitors == 0 || dwListSize == 0 ||
 586         (phUnsafeMonitorList == NULL && prcUnsafeMonitorList == NULL))
 587     {
 588         /* Simple case - just return monitors count */
 589         TRACE("cMonitors = %d\n", cMonitors);
 590         iRet = cMonitors;
 591         goto cleanup;
 592     }
 593
 594     /* Allocate safe buffers */
 595     if (phUnsafeMonitorList != NULL && dwListSize != 0)
 596     {
 597         phMonitorList = ExAllocatePoolWithTag(PagedPool, sizeof (HMONITOR) * dwListSize, USERTAG_MONITORRECTS);
 598         if (phMonitorList == NULL)
 599         {
 600             EngSetLastError(ERROR_NOT_ENOUGH_MEMORY);
 601             goto cleanup;
 602         }
 603     }
 604     if (prcUnsafeMonitorList != NULL && dwListSize != 0)
 605     {
 606         prcMonitorList = ExAllocatePoolWithTag(PagedPool, sizeof (RECT) * dwListSize, USERTAG_MONITORRECTS);
 607         if (prcMonitorList == NULL)
 608         {
 609             EngSetLastError(ERROR_NOT_ENOUGH_MEMORY);
 610             goto cleanup;
 611         }
 612     }
 613
 614     /* Get intersecting monitors */
 615     cMonitors = IntGetMonitorsFromRect(pRect, phMonitorList, prcMonitorList,
 616                                        dwListSize, MONITOR_DEFAULTTONULL);
 617
 618     if (hdc != NULL && pRect != NULL && prcMonitorList != NULL)
 619         for (i = 0; i < cMonitors; i++)
 620         {
 621             prcMonitorList[i].left -= DcRect.left;
 622             prcMonitorList[i].right -= DcRect.left;
 623             prcMonitorList[i].top -= DcRect.top;
 624             prcMonitorList[i].bottom -= DcRect.top;
 625         }
 626
 627     /* Output result */
 628     if (phUnsafeMonitorList != NULL && dwListSize != 0)
 629     {
 630         Status = MmCopyToCaller(phUnsafeMonitorList, phMonitorList, sizeof(HMONITOR) * dwListSize);
 631         if (!NT_SUCCESS(Status))
 632         {
 633             SetLastNtError(Status);
 634             goto cleanup;
 635         }
 636     }
 637     if (prcUnsafeMonitorList != NULL && dwListSize != 0)
 638     {
 639         Status = MmCopyToCaller(prcUnsafeMonitorList, prcMonitorList, sizeof(RECT) * dwListSize);
 640         if (!NT_SUCCESS(Status))
 641         {
 642             SetLastNtError(Status);
 643             goto cleanup;
 644         }
 645     }
 646
 647     /* Return monitors count on success */
 648     iRet = cMonitors;
 649
 650 cleanup:
 651     if (phMonitorList)
 652         ExFreePoolWithTag(phMonitorList, USERTAG_MONITORRECTS);
 653     if (prcMonitorList)
 654         ExFreePoolWithTag(prcMonitorList, USERTAG_MONITORRECTS);
 655
 656     UserLeave();
 657     return iRet;
 658 }
 659
 660 /* NtUserGetMonitorInfo
 661  *
 662  * Retrieves information about a given monitor
 663  *
 664  * Arguments
 665  *
 666  *   hMonitor
 667  *      Handle to a monitor for which to get information
 668  *
 669  *   pMonitorInfoUnsafe
 670  *      Pointer to a MONITORINFO struct which is filled with the information.
 671  *      The cbSize member must be set to sizeof(MONITORINFO) or
 672  *      sizeof(MONITORINFOEX). Even if set to sizeof(MONITORINFOEX) only parts
 673  *      from MONITORINFO will be filled.
 674  *
 675  *   pDevice
 676  *      Pointer to a UNICODE_STRING which will recieve the device's name. The
 677  *      length should be CCHDEVICENAME
 678  *      Can be NULL
 679  *
 680  * Return value
 681  *   TRUE on success; FALSE on failure (calls SetLastNtError())
 682  *
 683  */
 684 BOOL
 685 APIENTRY
 686 NtUserGetMonitorInfo(
 687     IN HMONITOR hMonitor,
 688     OUT LPMONITORINFO pMonitorInfoUnsafe)
 689 {
 690     PMONITOR pMonitor;
 691     MONITORINFOEXW MonitorInfo;
 692     NTSTATUS Status;
 693     BOOL bRet = FALSE;
 694     PWCHAR pwstrDeviceName;
 695
 696     TRACE("Enter NtUserGetMonitorInfo\n");
 697     UserEnterShared();
 698
 699     /* Get monitor object */
 700     pMonitor = UserGetMonitorObject(hMonitor);
 701     if (!pMonitor)
 702     {
 703         TRACE("Couldnt find monitor 0x%lx\n", hMonitor);
 704         goto cleanup;
 705     }
 706
 707     /* Check if pMonitorInfoUnsafe is valid */
 708     if(pMonitorInfoUnsafe == NULL)
 709     {
 710         SetLastNtError(STATUS_INVALID_PARAMETER);
 711         goto cleanup;
 712     }
 713
 714     pwstrDeviceName = ((PPDEVOBJ)(pMonitor->hDev))->pGraphicsDevice->szWinDeviceName;
 715
 716     /* Get size of pMonitorInfoUnsafe */
 717     Status = MmCopyFromCaller(&MonitorInfo.cbSize, &pMonitorInfoUnsafe->cbSize, sizeof(MonitorInfo.cbSize));
 718     if (!NT_SUCCESS(Status))
 719     {
 720         SetLastNtError(Status);
 721         goto cleanup;
 722     }
 723
 724     /* Check if size of struct is valid */
 725     if (MonitorInfo.cbSize != sizeof(MONITORINFO) &&
 726         MonitorInfo.cbSize != sizeof(MONITORINFOEXW))
 727     {
 728         SetLastNtError(STATUS_INVALID_PARAMETER);
 729         goto cleanup;
 730     }
 731
 732     /* Fill monitor info */
 733     MonitorInfo.rcMonitor = pMonitor->rcMonitor;
 734     MonitorInfo.rcWork = pMonitor->rcWork;
 735     MonitorInfo.dwFlags = 0;
 736     if (pMonitor->IsPrimary)
 737         MonitorInfo.dwFlags |= MONITORINFOF_PRIMARY;
 738
 739     /* Fill device name */
 740     if (MonitorInfo.cbSize == sizeof(MONITORINFOEXW))
 741     {
 742         RtlStringCbCopyNExW(MonitorInfo.szDevice,
 743                           sizeof(MonitorInfo.szDevice),
 744                           pwstrDeviceName,
 745                           (wcslen(pwstrDeviceName)+1) * sizeof(WCHAR),
 746                           NULL, NULL, STRSAFE_FILL_BEHIND_NULL);
 747     }
 748
 749     /* Output data */
 750     Status = MmCopyToCaller(pMonitorInfoUnsafe, &MonitorInfo, MonitorInfo.cbSize);
 751     if (!NT_SUCCESS(Status))
 752     {
 753         TRACE("GetMonitorInfo: MmCopyToCaller failed\n");
 754         SetLastNtError(Status);
 755         goto cleanup;
 756     }
 757
 758     TRACE("GetMonitorInfo: success\n");
 759     bRet = TRUE;
 760
 761 cleanup:
 762     TRACE("Leave NtUserGetMonitorInfo, ret=%i\n", bRet);
 763     UserLeave();
 764     return bRet;
 765 }
 766
 767 /* NtUserMonitorFromPoint
 768  *
 769  * Returns a handle to the monitor containing the given point.
 770  *
 771  * Arguments
 772  *
 773  *   pt
 774  *     Point for which to find monitor
 775  *
 776  *   dwFlags
 777  *     Specifies the behaviour if the point isn't on any of the monitors.
 778  *
 779  * Return value
 780  *   If the point is found a handle to the monitor is returned; if not the
 781  *   return value depends on dwFlags
 782  */
 783 HMONITOR
 784 APIENTRY
 785 NtUserMonitorFromPoint(
 786     IN POINT pt,
 787     IN DWORD dwFlags)
 788 {
 789     INT cMonitors;
 790     RECTL rc;
 791     HMONITOR hMonitor = NULL;
 792
 793     /* Check if flags are valid */
 794     if (dwFlags != MONITOR_DEFAULTTONULL &&
 795         dwFlags != MONITOR_DEFAULTTOPRIMARY &&
 796         dwFlags != MONITOR_DEFAULTTONEAREST)
 797     {
 798         EngSetLastError(ERROR_INVALID_FLAGS);
 799         return NULL;
 800     }
 801
 802     /* Fill rect (bottom-right exclusive) */
 803     rc.left = pt.x;
 804     rc.right = pt.x + 1;
 805     rc.top = pt.y;
 806     rc.bottom = pt.y + 1;
 807
 808     UserEnterShared();
 809
 810     /* Find intersecting monitor */
 811     cMonitors = IntGetMonitorsFromRect(&rc, &hMonitor, NULL, 1, dwFlags);
 812
 813     UserLeave();
 814     return hMonitor;
 815 }
 816
 817 /* NtUserMonitorFromRect
 818  *
 819  * Returns a handle to the monitor having the largest intersection with a
 820  * given rectangle
 821  *
 822  * Arguments
 823  *
 824  *   pRectUnsafe
 825  *     Pointer to a RECT for which to find monitor
 826  *
 827  *   dwFlags
 828  *     Specifies the behaviour if no monitor intersects the given rect
 829  *
 830  * Return value
 831  *   If a monitor intersects the rect a handle to it is returned; if not the
 832  *   return value depends on dwFlags
 833  */
 834 HMONITOR
 835 APIENTRY
 836 NtUserMonitorFromRect(
 837     IN LPCRECTL pRectUnsafe,
 838     IN DWORD dwFlags)
 839 {
 840     ULONG cMonitors, LargestArea = 0, i;
 841     PRECTL prcMonitorList = NULL;
 842     HMONITOR *phMonitorList = NULL;
 843     HMONITOR hMonitor = NULL;
 844     RECTL Rect;
 845     NTSTATUS Status;
 846
 847     /* Check if flags are valid */
 848     if (dwFlags != MONITOR_DEFAULTTONULL &&
 849         dwFlags != MONITOR_DEFAULTTOPRIMARY &&
 850         dwFlags != MONITOR_DEFAULTTONEAREST)
 851     {
 852         EngSetLastError(ERROR_INVALID_FLAGS);
 853         return NULL;
 854     }
 855
 856     /* Copy rectangle to safe buffer */
 857     Status = MmCopyFromCaller(&Rect, pRectUnsafe, sizeof (RECT));
 858     if (!NT_SUCCESS(Status))
 859     {
 860         SetLastNtError(Status);
 861         return NULL;
 862     }
 863
 864     UserEnterShared();
 865
 866     /* Find intersecting monitors */
 867     cMonitors = IntGetMonitorsFromRect(&Rect, &hMonitor, NULL, 1, dwFlags);
 868     if (cMonitors <= 1)
 869     {
 870         /* No or one monitor found. Just return handle. */
 871         goto cleanup;
 872     }
 873
 874     /* There is more than one monitor. Find monitor with largest intersection.
 875        Temporary reset hMonitor */
 876     hMonitor = NULL;
 877
 878     /* Allocate helper buffers */
 879     phMonitorList = ExAllocatePoolWithTag(PagedPool,
 880                                           sizeof(HMONITOR) * cMonitors,
 881                                           USERTAG_MONITORRECTS);
 882     if (phMonitorList == NULL)
 883     {
 884         EngSetLastError(ERROR_NOT_ENOUGH_MEMORY);
 885         goto cleanup;
 886     }
 887
 888     prcMonitorList = ExAllocatePoolWithTag(PagedPool,
 889                                            sizeof(RECT) * cMonitors,
 890                                            USERTAG_MONITORRECTS);
 891     if (prcMonitorList == NULL)
 892     {
 893         EngSetLastError(ERROR_NOT_ENOUGH_MEMORY);
 894         goto cleanup;
 895     }
 896
 897     /* Get intersecting monitors again but now with rectangle list */
 898     cMonitors = IntGetMonitorsFromRect(&Rect, phMonitorList, prcMonitorList,
 899                                        cMonitors, 0);
 900
 901     /* Find largest intersection */
 902     for (i = 0; i < cMonitors; i++)
 903     {
 904         ULONG Area = (prcMonitorList[i].right - prcMonitorList[i].left) *
 905                      (prcMonitorList[i].bottom - prcMonitorList[i].top);
 906         if (Area >= LargestArea)
 907         {
 908             hMonitor = phMonitorList[i];
 909             LargestArea = Area;
 910         }
 911     }
 912
 913 cleanup:
 914     if (phMonitorList)
 915         ExFreePoolWithTag(phMonitorList, USERTAG_MONITORRECTS);
 916     if (prcMonitorList)
 917         ExFreePoolWithTag(prcMonitorList, USERTAG_MONITORRECTS);
 918     UserLeave();
 919
 920     return hMonitor;
 921 }
 922
 923
 924 HMONITOR
 925 APIENTRY
 926 NtUserMonitorFromWindow(
 927     IN HWND hWnd,
 928     IN DWORD dwFlags)
 929 {
 930     PWND pWnd;
 931     HMONITOR hMonitor = NULL;
 932     RECTL Rect = {0, 0, 0, 0};
 933
 934     TRACE("Enter NtUserMonitorFromWindow\n");
 935
 936     /* Check if flags are valid */
 937     if (dwFlags != MONITOR_DEFAULTTONULL &&
 938         dwFlags != MONITOR_DEFAULTTOPRIMARY &&
 939         dwFlags != MONITOR_DEFAULTTONEAREST)
 940     {
 941         EngSetLastError(ERROR_INVALID_FLAGS);
 942         return NULL;
 943     }
 944
 945     UserEnterShared();
 946
 947     /* If window is given, use it first */
 948     if (hWnd)
 949     {
 950         /* Get window object */
 951         pWnd = UserGetWindowObject(hWnd);
 952         if (!pWnd)
 953             goto cleanup;
 954
 955         /* Find only monitors which have intersection with given window */
 956         Rect.left = Rect.right = pWnd->rcWindow.left;
 957         Rect.top = Rect.bottom = pWnd->rcWindow.bottom;
 958     }
 959
 960     /* Find monitors now */
 961     IntGetMonitorsFromRect(&Rect, &hMonitor, NULL, 1, dwFlags);
 962
 963 cleanup:
 964     TRACE("Leave NtUserMonitorFromWindow, ret=%p\n", hMonitor);
 965     UserLeave();
 966     return hMonitor;
 967 }