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Update VNC module resize functionality

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Significant updates for the VNC module:-
1) Support for the new API calls allowing both server and client
   multi-monitor resizes.
2) The s member variable of the vnc_screen_layout structure is no longer
   dynamically allocated.
3) The module server_width and server_height member variables are
   removed as these are just duplicating server_layout.total_width and
   server_layout.total_height.
4) When the server screens are resized, there is no need to restart the
   entire resize state machine as we already know at this point that
   the server supports resizing.
This commit is contained in:
matt335672 2024-02-15 15:57:47 +00:00 committed by Koichiro Iwao
parent dc6ac9758b
commit 9f422cc306
2 changed files with 205 additions and 229 deletions
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432
vnc/vnc.c
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@ -149,17 +149,13 @@ log_screen_layout(const enum logLevels lvl, const char *source,
* @param a First structure
* @param b Second structure
*
* @return Suitable for sorting structures with ID as the primary key
* @return Suitable for sorting structures on (x, y, width, height)
*/
static int cmp_vnc_screen(const struct vnc_screen *a,
const struct vnc_screen *b)
{
int result = 0;
if (a->id != b->id)
{
result = a->id - b->id;
}
else if (a->x != b->x)
if (a->x != b->x)
{
result = a->x - b->x;
}
@ -211,9 +207,7 @@ static int vnc_screen_layouts_equal(const struct vnc_screen_layout *a,
* @return != 0 for error
*
* @pre The next octet read from v->trans is the number of screens
* @pre layout is not already allocated
*
* @post if call is successful, layout->s must be freed after use.
* @post Returned structure is in increasing ID order
* @post layout->total_width is untouched
* @post layout->total_height is untouched
@ -225,10 +219,8 @@ read_extended_desktop_size_rect(struct vnc *v,
struct stream *s;
int error;
unsigned int count;
struct vnc_screen *screens;
layout->count = 0;
layout->s = NULL;
make_stream(s);
init_stream(s, 8192);
@ -239,46 +231,41 @@ read_extended_desktop_size_rect(struct vnc *v,
{
/* Get the number of screens */
in_uint8(s, count);
in_uint8s(s, 3);
error = trans_force_read_s(v->trans, s, 16 * count);
if (error == 0)
if (count <= 0 || count > CLIENT_MONITOR_DATA_MAXIMUM_MONITORS)
{
screens = g_new(struct vnc_screen, count);
if (screens == NULL)
{
LOG(LOG_LEVEL_ERROR,
"VNC : Can't alloc for %d screens", count);
error = 1;
}
else
LOG(LOG_LEVEL_ERROR,
"Bad monitor count %d in ExtendedDesktopSize rectangle",
count);
error = 1;
}
else
{
in_uint8s(s, 3);
error = trans_force_read_s(v->trans, s, 16 * count);
if (error == 0)
{
unsigned int i;
for (i = 0 ; i < count ; ++i)
{
in_uint32_be(s, screens[i].id);
in_uint16_be(s, screens[i].x);
in_uint16_be(s, screens[i].y);
in_uint16_be(s, screens[i].width);
in_uint16_be(s, screens[i].height);
in_uint32_be(s, screens[i].flags);
in_uint32_be(s, layout->s[i].id);
in_uint16_be(s, layout->s[i].x);
in_uint16_be(s, layout->s[i].y);
in_uint16_be(s, layout->s[i].width);
in_uint16_be(s, layout->s[i].height);
in_uint32_be(s, layout->s[i].flags);
}
/* sort monitors in increasing ID order */
qsort(screens, count, sizeof(screens[0]),
/* sort monitors in increasing (x,y) order */
qsort(layout->s, count, sizeof(layout->s[0]),
(int (*)(const void *, const void *))cmp_vnc_screen);
layout->count = count;
}
}
}
free_stream(s);
if (error == 0)
{
layout->count = count;
layout->s = screens;
}
return error;
}
@ -326,88 +313,76 @@ send_set_desktop_size(struct vnc *v, const struct vnc_screen_layout *layout)
}
/**************************************************************************//**
* Sets up a single-screen vnc_screen_layout structure
*
* @param layout Structure to set up
* @param width New client width
* @param height New client height
*
* @pre layout->count must be valid
* @pre layout->s must be valid
* Initialises a vnc_screen_layout as a single screen
* @param[in] width Screen Width
* @param[in] height Screen Height
* @param[out] layout Layout to initialise
*/
static void
set_single_screen_layout(struct vnc_screen_layout *layout,
int width, int height)
init_single_screen_layout(int width, int height,
struct vnc_screen_layout *layout)
{
int id = 0;
int flags = 0;
layout->total_width = width;
layout->total_height = height;
if (layout->count == 0)
{
/* No previous layout */
layout->s = g_new(struct vnc_screen, 1);
}
else
{
/* Keep the ID and flags from the previous first screen */
id = layout->s[0].id;
flags = layout->s[0].flags;
if (layout->count > 1)
{
g_free(layout->s);
layout->s = g_new(struct vnc_screen, 1);
}
}
layout->count = 1;
layout->s[0].id = id;
layout->s[0].id = 0;
layout->s[0].x = 0;
layout->s[0].y = 0;
layout->s[0].width = width;
layout->s[0].height = height;
layout->s[0].flags = flags;
layout->s[0].flags = 0;
}
/**************************************************************************//**
* Resize the client as a single screen
* Resize the client to match the server_layout
*
* @param v VNC object
* @param update_in_progress True if there's a painter update in progress
* @param width New client width
* @param height New client height
* @return != 0 for error
*
* The new client layout is recorded in v->client_layout. If the client was
* multi-screen before this call, it won't be afterwards.
* The new client layout is recorded in v->client_layout.
*/
static int
resize_client(struct vnc *v, int update_in_progress, int width, int height)
resize_client_to_server(struct vnc *v, int update_in_progress)
{
int error = 0;
unsigned int i;
const struct vnc_screen_layout *sl = &v->server_layout;
struct monitor_info client_mons[CLIENT_MONITOR_DATA_MAXIMUM_MONITORS] = {0};
if (v->client_layout.count != 1 ||
v->client_layout.total_width != width ||
v->client_layout.total_height != height)
if (sl->count <= 0 ||
sl->count > CLIENT_MONITOR_DATA_MAXIMUM_MONITORS)
{
if (update_in_progress)
{
error = v->server_end_update(v);
}
LOG(LOG_LEVEL_ERROR, "%s: Programming error. Bad monitors %d",
__func__, sl->count);
return 1;
}
// Convert the server monitors into client monitors
for (i = 0; i < sl->count; ++i)
{
client_mons[i].left = sl->s[i].x;
client_mons[i].top = sl->s[i].y;
client_mons[i].right = sl->s[i].x + sl->s[i].width - 1;
client_mons[i].bottom = sl->s[i].y + sl->s[i].height - 1;
}
if (update_in_progress && v->server_end_update(v) != 0)
{
error = 1;
}
else
{
error = v->client_monitor_resize(v, sl->total_width, sl->total_height,
sl->count, client_mons);
if (error == 0)
{
error = v->server_reset(v, width, height, v->server_bpp);
if (error == 0)
{
set_single_screen_layout(&v->client_layout, width, height);
if (update_in_progress)
{
error = v->server_begin_update(v);
}
}
v->client_layout = *sl;
}
if (update_in_progress && v->server_begin_update(v) != 0)
{
error = 1;
}
}
@ -416,50 +391,53 @@ resize_client(struct vnc *v, int update_in_progress, int width, int height)
/**************************************************************************//**
* Resize the attached client from a layout
* Resize the server to the client layout
*
* @param v VNC object
* @param update_in_progress True if there's a painter update in progress
* @param layout Desired layout from server
* @return != 0 for error
*
* This has some limitations. We have no way to move multiple screens about
* on a connected client, and so we are not able to change the client unless
* we're changing to a single screen layout.
* The new client layout is recorded in v->client_layout.
*/
static int
resize_client_from_layout(struct vnc *v,
int update_in_progress,
const struct vnc_screen_layout *layout)
resize_server_to_client_layout(struct vnc *v)
{
int error = 0;
if (!vnc_screen_layouts_equal(&v->client_layout, layout))
if (v->resize_supported != VRSS_SUPPORTED)
{
LOG(LOG_LEVEL_ERROR, "%s: Asked to resize server, but not possible",
__func__);
error = 1;
}
else if (vnc_screen_layouts_equal(&v->server_layout, &v->client_layout))
{
LOG(LOG_LEVEL_DEBUG, "Server layout is the same "
"as the client layout");
v->resize_status = VRS_DONE;
}
else
{
/*
* we don't have the capability to resize to anything other
* than a single screen.
* If we've only got one screen, and the other side has
* only got one screen, we will preserve their screen ID
* and any flags. This may prevent us sending an unwanted
* SetDesktopSize message if the screen dimensions are
* a match. We can't do this with more than one screen,
* as we have no way to map different IDs
*/
if (layout->count != 1)
if (v->server_layout.count == 1 && v->client_layout.count == 1)
{
LOG(LOG_LEVEL_ERROR,
"VNC Resize to %d screen(s) from %d screen(s) "
"not implemented",
v->client_layout.count, layout->count);
LOG(LOG_LEVEL_DEBUG, "VNC "
"setting screen id to %d from server",
v->server_layout.s[0].id);
/* Dump some useful info, in case we get here when we don't
* need to */
log_screen_layout(LOG_LEVEL_ERROR, "OldLayout", &v->client_layout);
log_screen_layout(LOG_LEVEL_ERROR, "NewLayout", layout);
error = 1;
}
else
{
error = resize_client(v,
update_in_progress,
layout->total_width,
layout->total_height);
v->client_layout.s[0].id = v->server_layout.s[0].id;
v->client_layout.s[0].flags = v->server_layout.s[0].flags;
}
LOG(LOG_LEVEL_DEBUG, "Changing server layout");
error = send_set_desktop_size(v, &v->client_layout);
v->resize_status = VRS_WAITING_FOR_RESIZE_CONFIRM;
}
return error;
@ -927,7 +905,6 @@ skip_encoding(struct vnc *v, int x, int y, int cx, int cy,
"x=%d, y=%d geom=%dx%d",
x, y, cx, cy);
error = read_extended_desktop_size_rect(v, &layout);
g_free(layout.s);
}
break;
@ -944,7 +921,7 @@ skip_encoding(struct vnc *v, int x, int y, int cx, int cy,
* Parses an entire framebuffer update message from the wire, and returns the
* first matching ExtendedDesktopSize encoding if found.
*
* Caller can check for a match by examining match_layout.s after the call
* Caller can check for a match by examining match_layout.count after the call
*
* @param v VNC object
* @param match Function to call to check for a match
@ -952,8 +929,6 @@ skip_encoding(struct vnc *v, int x, int y, int cx, int cy,
* @param [out] match_y Matching y parameter for an encoding (if needed)
* @param [out] match_layout Returned layout for the encoding
* @return != 0 for error
*
* @post After a successful call, match_layout.s must be free'd
*/
static int
find_matching_extended_rect(struct vnc *v,
@ -971,8 +946,7 @@ find_matching_extended_rect(struct vnc *v,
int cx;
int cy;
encoding_type encoding;
match_layout->s = NULL;
int found = 0;
make_stream(s);
init_stream(s, 8192);
@ -1002,14 +976,14 @@ find_matching_extended_rect(struct vnc *v,
in_uint32_be(s, encoding);
if (encoding == RFB_ENC_EXTENDED_DESKTOP_SIZE &&
match_layout->s == NULL &&
!found &&
match(x, y, cx, cy))
{
LOG(LOG_LEVEL_DEBUG,
"VNC matched ExtendedDesktopSize rectangle "
"x=%d, y=%d geom=%dx%d",
x, y, cx, cy);
found = 1;
error = read_extended_desktop_size_rect(v, match_layout);
if (match_x)
{
@ -1065,6 +1039,7 @@ send_update_request_for_resize_status(struct vnc *v)
switch (v->resize_status)
{
case VRS_WAITING_FOR_FIRST_UPDATE:
case VRS_WAITING_FOR_RESIZE_CONFIRM:
/*
* Ask for an immediate, minimal update.
*/
@ -1078,20 +1053,6 @@ send_update_request_for_resize_status(struct vnc *v)
error = lib_send_copy(v, s);
break;
case VRS_WAITING_FOR_RESIZE_CONFIRM:
/*
* Ask for a deferred minimal update.
*/
out_uint8(s, RFB_C2S_FRAMEBUFFER_UPDATE_REQUEST);
out_uint8(s, 1); /* incremental == 1 : Changes only */
out_uint16_be(s, 0);
out_uint16_be(s, 0);
out_uint16_be(s, 1);
out_uint16_be(s, 1);
s_mark_end(s);
error = lib_send_copy(v, s);
break;
default:
/*
* Ask for a full update from the server
@ -1102,8 +1063,8 @@ send_update_request_for_resize_status(struct vnc *v)
out_uint8(s, 0); /* incremental == 0 : Full update */
out_uint16_be(s, 0);
out_uint16_be(s, 0);
out_uint16_be(s, v->server_width);
out_uint16_be(s, v->server_height);
out_uint16_be(s, v->server_layout.total_width);
out_uint16_be(s, v->server_layout.total_height);
s_mark_end(s);
error = lib_send_copy(v, s);
}
@ -1159,12 +1120,15 @@ lib_framebuffer_first_update(struct vnc *v)
&layout);
if (error == 0)
{
if (layout.s != NULL)
if (layout.count > 0)
{
LOG(LOG_LEVEL_DEBUG, "VNC server supports resizing");
v->resize_supported = VRSS_SUPPORTED;
v->server_layout = layout;
/* Force the client geometry over to the server */
log_screen_layout(LOG_LEVEL_INFO, "OldLayout", &layout);
log_screen_layout(LOG_LEVEL_INFO, "ClientLayout", &v->client_layout);
log_screen_layout(LOG_LEVEL_INFO, "OldServerLayout", &layout);
/*
* If we've only got one screen, and the other side has
@ -1184,32 +1148,19 @@ lib_framebuffer_first_update(struct vnc *v)
v->client_layout.s[0].flags = layout.s[0].flags;
}
if (vnc_screen_layouts_equal(&layout, &v->client_layout))
{
LOG(LOG_LEVEL_DEBUG, "Server layout is the same "
"as the client layout");
v->resize_status = VRS_DONE;
}
else
{
LOG(LOG_LEVEL_DEBUG, "Server layout differs from "
"the client layout. Changing server layout");
error = send_set_desktop_size(v, &v->client_layout);
v->resize_status = VRS_WAITING_FOR_RESIZE_CONFIRM;
}
resize_server_to_client_layout(v);
}
else
{
LOG(LOG_LEVEL_DEBUG, "VNC server does not support resizing");
v->resize_supported = VRSS_NOT_SUPPORTED;
/* Force client to same size as server */
LOG(LOG_LEVEL_DEBUG, "Resizing client to server %dx%d",
v->server_width, v->server_height);
error = resize_client(v, 0, v->server_width, v->server_height);
v->server_layout.total_width, v->server_layout.total_height);
error = resize_client_to_server(v, 0);
v->resize_status = VRS_DONE;
}
g_free(layout.s);
}
if (error == 0)
@ -1224,7 +1175,7 @@ lib_framebuffer_first_update(struct vnc *v)
* Looks for a resize confirm in a framebuffer update request
*
* If the server supports resizes from us, this is used to find the
* reply to our initial resize request. See The RFB community wiki for details.
* reply to our resize request. See The RFB community wiki for details.
*
* @param v VNC object
* @return != 0 for error
@ -1243,18 +1194,17 @@ lib_framebuffer_waiting_for_resize_confirm(struct vnc *v)
&layout);
if (error == 0)
{
if (layout.s != NULL)
if (layout.count > 0)
{
if (response_code == 0)
{
LOG(LOG_LEVEL_DEBUG, "VNC server successfully resized");
log_screen_layout(LOG_LEVEL_INFO, "NewLayout", &layout);
v->server_layout = layout;
// If this resize was requested by the client mid-session
// (dynamic resize), we need to tell xrdp_mm that
// it's OK to continue with the resize state machine.
// We do this by sending a reset with bpp == 0
error = v->server_reset(v, v->server_width,
v->server_height, 0);
error = v->server_monitor_resize_done(v);
}
else
{
@ -1263,14 +1213,11 @@ lib_framebuffer_waiting_for_resize_confirm(struct vnc *v)
response_code,
rfb_get_eds_status_msg(response_code));
/* Force client to same size as server */
LOG(LOG_LEVEL_WARNING, "Resizing client to server %dx%d",
v->server_width, v->server_height);
error = resize_client(v, 0, v->server_width, v->server_height);
LOG(LOG_LEVEL_WARNING, "Resizing client to server");
error = resize_client_to_server(v, 0);
}
v->resize_status = VRS_DONE;
}
g_free(layout.s);
}
if (error == 0)
@ -1415,9 +1362,8 @@ lib_framebuffer_update(struct vnc *v)
else if (encoding == RFB_ENC_DESKTOP_SIZE)
{
/* Server end has resized */
v->server_width = cx;
v->server_height = cy;
error = resize_client(v, 1, cx, cy);
init_single_screen_layout(cx, cy, &v->server_layout);
error = resize_client_to_server(v, 1);
}
else if (encoding == RFB_ENC_EXTENDED_DESKTOP_SIZE)
{
@ -1427,11 +1373,14 @@ lib_framebuffer_update(struct vnc *v)
/* If this is a reply to a request from us, x == 1 */
if (error == 0 && x != 1)
{
v->server_width = layout.total_width;
v->server_height = layout.total_height;
error = resize_client_from_layout(v, 1, &layout);
if (!vnc_screen_layouts_equal(&v->server_layout, &layout))
{
v->server_layout = layout;
log_screen_layout(LOG_LEVEL_INFO, "NewServerLayout",
&v->server_layout);
error = resize_client_to_server(v, 1);
}
}
g_free(layout.s);
}
else
{
@ -1456,8 +1405,8 @@ lib_framebuffer_update(struct vnc *v)
out_uint8(s, 1); /* incremental == 1 : Changes only */
out_uint16_be(s, 0);
out_uint16_be(s, 0);
out_uint16_be(s, v->server_width);
out_uint16_be(s, v->server_height);
out_uint16_be(s, v->server_layout.total_width);
out_uint16_be(s, v->server_layout.total_height);
s_mark_end(s);
error = lib_send_copy(v, s);
}
@ -1831,8 +1780,11 @@ lib_mod_connect(struct vnc *v)
if (error == 0)
{
in_uint16_be(s, v->server_width);
in_uint16_be(s, v->server_height);
int width;
int height;
in_uint16_be(s, width);
in_uint16_be(s, height);
init_single_screen_layout(width, height, &v->server_layout);
init_stream(pixel_format, 8192);
v->server_msg(v, "VNC receiving pixel format", 0);
@ -2000,6 +1952,7 @@ lib_mod_connect(struct vnc *v)
if (error == 0)
{
v->resize_supported = VRSS_UNKNOWN;
v->resize_status = VRS_WAITING_FOR_FIRST_UPDATE;
error = send_update_request_for_resize_status(v);
}
@ -2061,33 +2014,40 @@ lib_mod_end(struct vnc *v)
/**************************************************************************//**
* Initialises the client layout from the Windows monitor definition.
*
* @param [out] layout Our layout
* @param [in] client_info WM info
* @param v VNC module
* @param [in] width session width
* @param [in] height session height
* @param [in] num_monitors (can be 0, meaning one monitor)
* @param [in] monitors Monitor definitions for num_monitors > 0
* @param [in] multimon_configured Whether multimon is configured
*/
static void
init_client_layout(struct vnc_screen_layout *layout,
const struct xrdp_client_info *client_info)
init_client_layout(struct vnc *v,
int width, int height,
int num_monitors,
const struct monitor_info *monitors)
{
uint32_t i;
layout->total_width = client_info->display_sizes.session_width;
layout->total_height = client_info->display_sizes.session_height;
layout->count = client_info->display_sizes.monitorCount;
layout->s = g_new(struct vnc_screen, layout->count);
for (i = 0 ; i < client_info->display_sizes.monitorCount ; ++i)
struct vnc_screen_layout *layout = &v->client_layout;
if (!v->multimon_configured || num_monitors < 1)
{
/* Use minfo_wm, as this is normalised for a top-left of (0,0)
* as required by RFC6143 */
layout->s[i].id = i;
layout->s[i].x = client_info->display_sizes.minfo_wm[i].left;
layout->s[i].y = client_info->display_sizes.minfo_wm[i].top;
layout->s[i].width = client_info->display_sizes.minfo_wm[i].right -
client_info->display_sizes.minfo_wm[i].left + 1;
layout->s[i].height = client_info->display_sizes.minfo_wm[i].bottom -
client_info->display_sizes.minfo_wm[i].top + 1;
layout->s[i].flags = 0;
init_single_screen_layout(width, height, layout);
}
else
{
layout->total_width = width;
layout->total_height = height;
layout->count = num_monitors;
unsigned int i;
for (i = 0 ; i < layout->count; ++i)
{
layout->s[i].id = i;
layout->s[i].x = monitors[i].left;
layout->s[i].y = monitors[i].top;
layout->s[i].width = monitors[i].right - monitors[i].left + 1;
layout->s[i].height = monitors[i].bottom - monitors[i].top + 1;
layout->s[i].flags = 0;
}
}
}
@ -2132,20 +2092,16 @@ lib_mod_set_param(struct vnc *v, const char *name, const char *value)
const struct xrdp_client_info *client_info =
(const struct xrdp_client_info *) value;
g_free(v->client_layout.s);
v->client_layout.count = 0;
v->multimon_configured = client_info->multimon;
/* Save monitor information from the client */
if (!client_info->multimon || client_info->display_sizes.monitorCount < 1)
{
set_single_screen_layout(&v->client_layout,
client_info->display_sizes.session_width,
client_info->display_sizes.session_height);
}
else
{
init_client_layout(&v->client_layout, client_info);
}
/* Save monitor information from the client
* Use minfo_wm, as this is normalised for a top-left of (0,0)
* as required by RFC6143 */
init_client_layout(v,
client_info->display_sizes.session_width,
client_info->display_sizes.session_height,
client_info->display_sizes.monitorCount,
client_info->display_sizes.minfo_wm);
log_screen_layout(LOG_LEVEL_DEBUG, "client_info", &v->client_layout);
}
@ -2186,6 +2142,10 @@ lib_mod_check_wait_objs(struct vnc *v)
if (v->trans != 0)
{
rv = trans_check_wait_objs(v->trans);
if (rv != 0)
{
LOG(LOG_LEVEL_ERROR, "VNC server closed connection");
}
}
}
return rv;
@ -2218,8 +2178,8 @@ lib_mod_suppress_output(struct vnc *v, int suppress,
out_uint8(s, 0); /* incremental == 0 : Full contents */
out_uint16_be(s, 0);
out_uint16_be(s, 0);
out_uint16_be(s, v->server_width);
out_uint16_be(s, v->server_height);
out_uint16_be(s, v->server_layout.total_width);
out_uint16_be(s, v->server_layout.total_height);
s_mark_end(s);
error = lib_send_copy(v, s);
free_stream(s);
@ -2238,12 +2198,29 @@ lib_mod_server_version_message(struct vnc *v)
/******************************************************************************/
/* return error */
int
lib_mod_server_monitor_resize(struct vnc *v, int width, int height)
lib_mod_server_monitor_resize(struct vnc *v, int width, int height,
int num_monitors,
const struct monitor_info *monitors,
int *in_progress)
{
int error = 0;
set_single_screen_layout(&v->client_layout, width, height);
v->resize_status = VRS_WAITING_FOR_FIRST_UPDATE;
error = send_update_request_for_resize_status(v);
int error;
*in_progress = 0;
init_client_layout(v, width, height, num_monitors, monitors);
if ((error = resize_server_to_client_layout(v)) == 0)
{
// If we're waiting for a confirmation, send an update request.
// According to the spec this should not be needed, but
// it works around a buggy VNC server not sending an
// ExtendedDesktopSize rectangle if the desktop change is
// small (eg. same dimensions, but 2 monitors -> 1 monitor)
if (v->resize_status == VRS_WAITING_FOR_RESIZE_CONFIRM &&
(error = send_update_request_for_resize_status(v)) == 0)
{
*in_progress = 1;
}
}
return error;
}
@ -2299,7 +2276,6 @@ mod_exit(tintptr handle)
return 0;
}
trans_delete(v->trans);
g_free(v->client_layout.s);
vnc_clip_exit(v);
g_free(v);
return 0;

2
vnc/vnc.h
View File

@ -47,7 +47,7 @@ struct vnc_screen_layout
int total_width;
int total_height;
unsigned int count;
/* For comparison, screens are sorted in increasing order of ID */
/* For comparison, screens are sorted in x, y, width, height) order */
struct vnc_screen s[CLIENT_MONITOR_DATA_MAXIMUM_MONITORS];
};