FreeRDP/client/X11/xf_monitor.c

/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * X11 Monitor Handling
 *
 * Copyright 2011 Marc-Andre Moreau <marcandre.moreau@gmail.com>
 * Copyright 2017 David Fort <contact@hardening-consulting.com>
 * Copyright 2018 Kai Harms <kharms@rangee.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <freerdp/config.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>

#include <winpr/assert.h>
#include <winpr/crt.h>

#include <freerdp/log.h>

#define TAG CLIENT_TAG("x11")

#ifdef WITH_XINERAMA
#include <X11/extensions/Xinerama.h>
#endif

#ifdef WITH_XRANDR
#include <X11/extensions/Xrandr.h>
#include <X11/extensions/randr.h>

#if (RANDR_MAJOR * 100 + RANDR_MINOR) >= 105
#define USABLE_XRANDR
#endif

#endif

#include "xf_monitor.h"

/* See MSDN Section on Multiple Display Monitors: http://msdn.microsoft.com/en-us/library/dd145071
 */

int xf_list_monitors(xfContext* xfc)
{
	Display* display = NULL;
	int major = 0;
	int minor = 0;
	int nmonitors = 0;
	display = XOpenDisplay(NULL);

	if (!display)
	{
		WLog_ERR(TAG, "failed to open X display");
		return -1;
	}

#if defined(USABLE_XRANDR)

	if (XRRQueryExtension(display, &major, &minor) &&
	    (XRRQueryVersion(display, &major, &minor) == True) && (major * 100 + minor >= 105))
	{
		XRRMonitorInfo* monitors =
		    XRRGetMonitors(display, DefaultRootWindow(display), 1, &nmonitors);

		for (int i = 0; i < nmonitors; i++)
		{
			printf("      %s [%d] %dx%d\t+%d+%d\n", monitors[i].primary ? "*" : " ", i,
			       monitors[i].width, monitors[i].height, monitors[i].x, monitors[i].y);
		}

		XRRFreeMonitors(monitors);
	}
	else
#endif
#ifdef WITH_XINERAMA
	    if (XineramaQueryExtension(display, &major, &minor))
	{
		if (XineramaIsActive(display))
		{
			XineramaScreenInfo* screen = XineramaQueryScreens(display, &nmonitors);

			for (int i = 0; i < nmonitors; i++)
			{
				printf("      %s [%d] %hdx%hd\t+%hd+%hd\n", (i == 0) ? "*" : " ", i,
				       screen[i].width, screen[i].height, screen[i].x_org, screen[i].y_org);
			}

			XFree(screen);
		}
	}
	else
#else
	{
		Screen* screen = ScreenOfDisplay(display, DefaultScreen(display));
		printf("      * [0] %dx%d\t+0+0\n", WidthOfScreen(screen), HeightOfScreen(screen));
	}

#endif
		XCloseDisplay(display);
	return 0;
}

static BOOL xf_is_monitor_id_active(xfContext* xfc, UINT32 id)
{
	const rdpSettings* settings = NULL;

	WINPR_ASSERT(xfc);

	settings = xfc->common.context.settings;
	WINPR_ASSERT(settings);

	const UINT32 NumMonitorIds = freerdp_settings_get_uint32(settings, FreeRDP_NumMonitorIds);
	if (NumMonitorIds == 0)
		return TRUE;

	for (UINT32 index = 0; index < NumMonitorIds; index++)
	{
		const UINT32* cur = freerdp_settings_get_pointer_array(settings, FreeRDP_MonitorIds, index);
		if (cur && (*cur == id))
			return TRUE;
	}

	return FALSE;
}

BOOL xf_detect_monitors(xfContext* xfc, UINT32* pMaxWidth, UINT32* pMaxHeight)
{
	BOOL rc = FALSE;
	int nmonitors = 0;
	UINT32 monitor_index = 0;
	BOOL primaryMonitorFound = FALSE;
	VIRTUAL_SCREEN* vscreen = NULL;
	rdpSettings* settings = NULL;
	int mouse_x = 0;
	int mouse_y = 0;
	int _dummy_i = 0;
	Window _dummy_w = 0;
	int current_monitor = 0;
	Screen* screen = NULL;
#if defined WITH_XINERAMA || defined WITH_XRANDR
	int major = 0;
	int minor = 0;
#endif
#if defined(USABLE_XRANDR)
	XRRMonitorInfo* rrmonitors = NULL;
	BOOL useXRandr = FALSE;
#endif

	if (!xfc || !pMaxWidth || !pMaxHeight || !xfc->common.context.settings)
		return FALSE;

	settings = xfc->common.context.settings;
	vscreen = &xfc->vscreen;
	*pMaxWidth = freerdp_settings_get_uint32(settings, FreeRDP_DesktopWidth);
	*pMaxHeight = freerdp_settings_get_uint32(settings, FreeRDP_DesktopHeight);

	if (freerdp_settings_get_uint64(settings, FreeRDP_ParentWindowId) > 0)
	{
		xfc->workArea.x = 0;
		xfc->workArea.y = 0;
		xfc->workArea.width = freerdp_settings_get_uint32(settings, FreeRDP_DesktopWidth);
		xfc->workArea.height = freerdp_settings_get_uint32(settings, FreeRDP_DesktopHeight);
		return TRUE;
	}

	/* get mouse location */
	if (!XQueryPointer(xfc->display, DefaultRootWindow(xfc->display), &_dummy_w, &_dummy_w,
	                   &mouse_x, &mouse_y, &_dummy_i, &_dummy_i, (void*)&_dummy_i))
		mouse_x = mouse_y = 0;

#if defined(USABLE_XRANDR)

	if (XRRQueryExtension(xfc->display, &major, &minor) &&
	    (XRRQueryVersion(xfc->display, &major, &minor) == True) && (major * 100 + minor >= 105))
	{
		rrmonitors =
		    XRRGetMonitors(xfc->display, DefaultRootWindow(xfc->display), 1, &vscreen->nmonitors);

		if (vscreen->nmonitors > 16)
			vscreen->nmonitors = 0;

		if (vscreen->nmonitors)
		{
			for (int i = 0; i < vscreen->nmonitors; i++)
			{
				MONITOR_INFO* cur_vscreen = &vscreen->monitors[i];
				const XRRMonitorInfo* cur_monitor = &rrmonitors[i];
				cur_vscreen->area.left = cur_monitor->x;
				cur_vscreen->area.top = cur_monitor->y;
				cur_vscreen->area.right = cur_monitor->x + cur_monitor->width - 1;
				cur_vscreen->area.bottom = cur_monitor->y + cur_monitor->height - 1;
				cur_vscreen->primary = cur_monitor->primary > 0;
			}
		}

		useXRandr = TRUE;
	}
	else
#endif
#ifdef WITH_XINERAMA
	    if (XineramaQueryExtension(xfc->display, &major, &minor) && XineramaIsActive(xfc->display))
	{
		XineramaScreenInfo* screenInfo = XineramaQueryScreens(xfc->display, &vscreen->nmonitors);

		if (vscreen->nmonitors > 16)
			vscreen->nmonitors = 0;

		if (vscreen->nmonitors)
		{
			for (int i = 0; i < vscreen->nmonitors; i++)
			{
				MONITOR_INFO* monitor = &vscreen->monitors[i];
				monitor->area.left = screenInfo[i].x_org;
				monitor->area.top = screenInfo[i].y_org;
				monitor->area.right = screenInfo[i].x_org + screenInfo[i].width - 1;
				monitor->area.bottom = screenInfo[i].y_org + screenInfo[i].height - 1;
			}
		}

		XFree(screenInfo);
	}

#endif
	xfc->fullscreenMonitors.top = xfc->fullscreenMonitors.bottom = xfc->fullscreenMonitors.left =
	    xfc->fullscreenMonitors.right = 0;

	/* Determine which monitor that the mouse cursor is on */
	if (vscreen->monitors)
	{
		for (int i = 0; i < vscreen->nmonitors; i++)
		{
			const MONITOR_INFO* monitor = &vscreen->monitors[i];

			if ((mouse_x >= monitor->area.left) && (mouse_x <= monitor->area.right) &&
			    (mouse_y >= monitor->area.top) && (mouse_y <= monitor->area.bottom))
			{
				current_monitor = i;
				break;
			}
		}
	}

	/*
	   Even for a single monitor, we need to calculate the virtual screen to support
	   window managers that do not implement all X window state hints.

	   If the user did not request multiple monitor or is using workarea
	   without remote app, we force the number of monitors be 1 so later
	   the rest of the client don't end up using more monitors than the user desires.
	 */
	if ((!freerdp_settings_get_bool(settings, FreeRDP_UseMultimon) &&
	     !freerdp_settings_get_bool(settings, FreeRDP_SpanMonitors)) ||
	    (freerdp_settings_get_bool(settings, FreeRDP_Workarea) &&
	     !freerdp_settings_get_bool(settings, FreeRDP_RemoteApplicationMode)))
	{
		/* If no monitors were specified on the command-line then set the current monitor as active
		 */
		if (freerdp_settings_get_uint32(settings, FreeRDP_NumMonitorIds) == 0)
		{
			UINT32 id = current_monitor;
			if (!freerdp_settings_set_pointer_len(settings, FreeRDP_MonitorIds, &id, 1))
				goto fail;
		}

		/* Always sets number of monitors from command-line to just 1.
		 * If the monitor is invalid then we will default back to current monitor
		 * later as a fallback. So, there is no need to validate command-line entry here.
		 */
		if (!freerdp_settings_set_uint32(settings, FreeRDP_NumMonitorIds, 1))
			goto fail;
	}

	/* WORKAROUND: With Remote Application Mode - using NET_WM_WORKAREA
	 * causes issues with the ability to fully size the window vertically
	 * (the bottom of the window area is never updated). So, we just set
	 * the workArea to match the full Screen width/height.
	 */
	if (freerdp_settings_get_bool(settings, FreeRDP_RemoteApplicationMode) || !xf_GetWorkArea(xfc))
	{
		/*
		   if only 1 monitor is enabled, use monitor area
		   this is required in case of a screen composed of more than one monitor
		   but user did not enable multimonitor
		*/
		if ((freerdp_settings_get_uint32(settings, FreeRDP_NumMonitorIds) == 1) &&
		    (vscreen->nmonitors > current_monitor))
		{
			MONITOR_INFO* monitor = vscreen->monitors + current_monitor;

			if (!monitor)
				goto fail;

			xfc->workArea.x = monitor->area.left;
			xfc->workArea.y = monitor->area.top;
			xfc->workArea.width = monitor->area.right - monitor->area.left + 1;
			xfc->workArea.height = monitor->area.bottom - monitor->area.top + 1;
		}
		else
		{
			xfc->workArea.x = 0;
			xfc->workArea.y = 0;
			xfc->workArea.width = WidthOfScreen(xfc->screen);
			xfc->workArea.height = HeightOfScreen(xfc->screen);
		}
	}

	if (freerdp_settings_get_bool(settings, FreeRDP_Fullscreen))
	{
		*pMaxWidth = WidthOfScreen(xfc->screen);
		*pMaxHeight = HeightOfScreen(xfc->screen);
	}
	else if (freerdp_settings_get_bool(settings, FreeRDP_Workarea))
	{
		*pMaxWidth = xfc->workArea.width;
		*pMaxHeight = xfc->workArea.height;
	}
	else if (freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen))
	{
		/* If we have specific monitor information then limit the PercentScreen value
		 * to only affect the current monitor vs. the entire desktop
		 */
		if (vscreen->nmonitors > 0)
		{
			if (!vscreen->monitors)
				goto fail;

			*pMaxWidth = vscreen->monitors[current_monitor].area.right -
			             vscreen->monitors[current_monitor].area.left + 1;
			*pMaxHeight = vscreen->monitors[current_monitor].area.bottom -
			              vscreen->monitors[current_monitor].area.top + 1;

			if (freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseWidth))
				*pMaxWidth = ((vscreen->monitors[current_monitor].area.right -
				               vscreen->monitors[current_monitor].area.left + 1) *
				              freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)) /
				             100;

			if (freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseHeight))
				*pMaxHeight = ((vscreen->monitors[current_monitor].area.bottom -
				                vscreen->monitors[current_monitor].area.top + 1) *
				               freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)) /
				              100;
		}
		else
		{
			*pMaxWidth = xfc->workArea.width;
			*pMaxHeight = xfc->workArea.height;

			if (freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseWidth))
				*pMaxWidth = (xfc->workArea.width *
				              freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)) /
				             100;

			if (freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseHeight))
				*pMaxHeight = (xfc->workArea.height *
				               freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)) /
				              100;
		}
	}
	else if (freerdp_settings_get_uint32(settings, FreeRDP_DesktopWidth) &&
	         freerdp_settings_get_uint32(settings, FreeRDP_DesktopHeight))
	{
		*pMaxWidth = freerdp_settings_get_uint32(settings, FreeRDP_DesktopWidth);
		*pMaxHeight = freerdp_settings_get_uint32(settings, FreeRDP_DesktopHeight);
	}

	/* Create array of all active monitors by taking into account monitors requested on the
	 * command-line */
	{
		UINT32 nr = 0;

		{
			const UINT32* ids = freerdp_settings_get_pointer(settings, FreeRDP_MonitorIds);
			if (ids)
				nr = *ids;
		}
		for (UINT32 i = 0; i < vscreen->nmonitors; i++)
		{
			MONITOR_ATTRIBUTES* attrs = NULL;

			if (!xf_is_monitor_id_active(xfc, (UINT32)i))
				continue;

			if (!vscreen->monitors)
				goto fail;

			rdpMonitor* monitor = freerdp_settings_get_pointer_array_writable(
			    settings, FreeRDP_MonitorDefArray, nmonitors);
			monitor->x = (vscreen->monitors[i].area.left *
			              (freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseWidth)
			                   ? freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)
			                   : 100)) /
			             100;
			monitor->y = (vscreen->monitors[i].area.top *
			              (freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseHeight)
			                   ? freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)
			                   : 100)) /
			             100;
			monitor->width =
			    ((vscreen->monitors[i].area.right - vscreen->monitors[i].area.left + 1) *
			     (freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseWidth)
			          ? freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)
			          : 100)) /
			    100;
			monitor->height =
			    ((vscreen->monitors[i].area.bottom - vscreen->monitors[i].area.top + 1) *
			     (freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseWidth)
			          ? freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)
			          : 100)) /
			    100;
			monitor->orig_screen = i;
#ifdef USABLE_XRANDR

			if (useXRandr && rrmonitors)
			{
				Rotation rot = 0;
				Rotation ret = 0;
				attrs = &monitor->attributes;
				attrs->physicalWidth = rrmonitors[i].mwidth;
				attrs->physicalHeight = rrmonitors[i].mheight;
				ret = XRRRotations(xfc->display, i, &rot);
				attrs->orientation = ret;
			}

#endif

			if ((UINT32)i == nr)
			{
				monitor->is_primary = TRUE;
				if (!freerdp_settings_set_uint32(settings, FreeRDP_MonitorLocalShiftX, monitor->x))
					goto fail;
				if (!freerdp_settings_set_uint32(settings, FreeRDP_MonitorLocalShiftY, monitor->y))
					goto fail;
				primaryMonitorFound = TRUE;
			}

			nmonitors++;
		}
	}

	/* If no monitor is active(bogus command-line monitor specification) - then lets try to fallback
	 * to go fullscreen on the current monitor only */
	if (nmonitors == 0 && vscreen->nmonitors > 0)
	{
		INT32 width = 0;
		INT32 height = 0;
		if (!vscreen->monitors)
			goto fail;

		width = vscreen->monitors[current_monitor].area.right -
		        vscreen->monitors[current_monitor].area.left + 1L;
		height = vscreen->monitors[current_monitor].area.bottom -
		         vscreen->monitors[current_monitor].area.top + 1L;

		rdpMonitor* monitor =
		    freerdp_settings_get_pointer_array_writable(settings, FreeRDP_MonitorDefArray, 0);
		if (!monitor)
			goto fail;

		monitor->x = vscreen->monitors[current_monitor].area.left;
		monitor->y = vscreen->monitors[current_monitor].area.top;
		monitor->width = MIN(width, (INT64)(*pMaxWidth));
		monitor->height = MIN(height, (INT64)(*pMaxHeight));
		monitor->orig_screen = current_monitor;
		nmonitors = 1;
	}

	if (!freerdp_settings_set_uint32(settings, FreeRDP_MonitorCount, nmonitors))
		goto fail;

	/* If we have specific monitor information */
	if (freerdp_settings_get_uint32(settings, FreeRDP_MonitorCount) > 0)
	{
		const rdpMonitor* cmonitor =
		    freerdp_settings_get_pointer_array(settings, FreeRDP_MonitorDefArray, 0);
		if (!cmonitor)
			goto fail;

		/* Initialize bounding rectangle for all monitors */
		int vX = cmonitor->x;
		int vY = cmonitor->y;
		int vR = vX + cmonitor->width;
		int vB = vY + cmonitor->height;
		xfc->fullscreenMonitors.top = xfc->fullscreenMonitors.bottom =
		    xfc->fullscreenMonitors.left = xfc->fullscreenMonitors.right = cmonitor->orig_screen;

		/* Calculate bounding rectangle around all monitors to be used AND
		 * also set the Xinerama indices which define left/top/right/bottom monitors.
		 */
		for (UINT32 i = 0; i < freerdp_settings_get_uint32(settings, FreeRDP_MonitorCount); i++)
		{
			rdpMonitor* monitor =
			    freerdp_settings_get_pointer_array_writable(settings, FreeRDP_MonitorDefArray, i);

			/* does the same as gdk_rectangle_union */
			int destX = MIN(vX, monitor->x);
			int destY = MIN(vY, monitor->y);
			int destR = MAX(vR, monitor->x + monitor->width);
			int destB = MAX(vB, monitor->y + monitor->height);

			if (vX != destX)
				xfc->fullscreenMonitors.left = monitor->orig_screen;

			if (vY != destY)
				xfc->fullscreenMonitors.top = monitor->orig_screen;

			if (vR != destR)
				xfc->fullscreenMonitors.right = monitor->orig_screen;

			if (vB != destB)
				xfc->fullscreenMonitors.bottom = monitor->orig_screen;

			vX = destX / ((freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseWidth)
			                   ? freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)
			                   : 100) /
			              100.);
			vY = destY / ((freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseHeight)
			                   ? freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)
			                   : 100) /
			              100.);
			vR = destR / ((freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseWidth)
			                   ? freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)
			                   : 100) /
			              100.);
			vB = destB / ((freerdp_settings_get_bool(settings, FreeRDP_PercentScreenUseHeight)
			                   ? freerdp_settings_get_uint32(settings, FreeRDP_PercentScreen)
			                   : 100) /
			              100.);
		}

		vscreen->area.left = 0;
		vscreen->area.right = vR - vX - 1;
		vscreen->area.top = 0;
		vscreen->area.bottom = vB - vY - 1;

		if (freerdp_settings_get_bool(settings, FreeRDP_Workarea))
		{
			vscreen->area.top = xfc->workArea.y;
			vscreen->area.bottom = xfc->workArea.height + xfc->workArea.y - 1;
		}

		if (!primaryMonitorFound)
		{
			/* If we have a command line setting we should use it */
			if (freerdp_settings_get_uint32(settings, FreeRDP_NumMonitorIds) > 0)
			{
				/* The first monitor is the first in the setting which should be used */
				UINT32* ids =
				    freerdp_settings_get_pointer_array_writable(settings, FreeRDP_MonitorIds, 0);
				if (ids)
					monitor_index = *ids;
			}
			else
			{
				/* This is the same as when we would trust the Xinerama results..
				   and set the monitor index to zero.
				   The monitor listed with /list:monitor on index zero is always the primary
				*/
				screen = DefaultScreenOfDisplay(xfc->display);
				monitor_index = XScreenNumberOfScreen(screen);
			}

			UINT32 j = monitor_index;
			rdpMonitor* pmonitor =
			    freerdp_settings_get_pointer_array_writable(settings, FreeRDP_MonitorDefArray, j);

			/* If the "default" monitor is not 0,0 use it */
			if ((pmonitor->x != 0) || (pmonitor->y != 0))
			{
				pmonitor->is_primary = TRUE;
				if (!freerdp_settings_set_uint32(settings, FreeRDP_MonitorLocalShiftX, pmonitor->x))
					goto fail;
				if (!freerdp_settings_set_uint32(settings, FreeRDP_MonitorLocalShiftY, pmonitor->y))
					goto fail;
			}
			else
			{
				/* Lets try to see if there is a monitor with a 0,0 coordinate and use it as a
				 * fallback*/
				for (UINT32 i = 0; i < freerdp_settings_get_uint32(settings, FreeRDP_MonitorCount);
				     i++)
				{
					rdpMonitor* monitor = freerdp_settings_get_pointer_array_writable(
					    settings, FreeRDP_MonitorDefArray, i);
					if (!primaryMonitorFound && monitor->x == 0 && monitor->y == 0)
					{
						monitor->is_primary = TRUE;
						if (!freerdp_settings_set_uint32(settings, FreeRDP_MonitorLocalShiftX,
						                                 monitor->x))
							goto fail;
						if (!freerdp_settings_set_uint32(settings, FreeRDP_MonitorLocalShiftY,
						                                 monitor->y))
							goto fail;
						primaryMonitorFound = TRUE;
					}
				}
			}
		}

		/* Subtract monitor shift from monitor variables for server-side use.
		 * We maintain monitor shift value as Window requires the primary monitor to have a
		 * coordinate of 0,0 In some X configurations, no monitor may have a coordinate of 0,0. This
		 * can also be happen if the user requests specific monitors from the command-line as well.
		 * So, we make sure to translate our primary monitor's upper-left corner to 0,0 on the
		 * server.
		 */
		for (UINT32 i = 0; i < freerdp_settings_get_uint32(settings, FreeRDP_MonitorCount); i++)
		{
			rdpMonitor* monitor =
			    freerdp_settings_get_pointer_array_writable(settings, FreeRDP_MonitorDefArray, i);
			monitor->x =
			    monitor->x - freerdp_settings_get_uint32(settings, FreeRDP_MonitorLocalShiftX);
			monitor->y =
			    monitor->y - freerdp_settings_get_uint32(settings, FreeRDP_MonitorLocalShiftY);
		}

		/* Set the desktop width and height according to the bounding rectangle around the active
		 * monitors */
		*pMaxWidth = MIN(*pMaxWidth, (UINT32)vscreen->area.right - vscreen->area.left + 1);
		*pMaxHeight = MIN(*pMaxHeight, (UINT32)vscreen->area.bottom - vscreen->area.top + 1);
	}

	/* some 2008 server freeze at logon if we announce support for monitor layout PDU with
	 * #monitors < 2. So let's announce it only if we have more than 1 monitor.
	 */
	if (freerdp_settings_get_uint32(settings, FreeRDP_MonitorCount) > 1)
	{
		if (!freerdp_settings_set_bool(settings, FreeRDP_SupportMonitorLayoutPdu, TRUE))
			goto fail;
	}

	rc = TRUE;
fail:
#ifdef USABLE_XRANDR

	if (rrmonitors)
		XRRFreeMonitors(rrmonitors);

#endif
	return rc;
}