gri3-wm/src/randr.c

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#undef I3__FILE__
#define I3__FILE__ "randr.c"
/*
* vim:ts=4:sw=4:expandtab
*
* i3 - an improved dynamic tiling window manager
* © 2009-2012 Michael Stapelberg and contributors (see also: LICENSE)
*
* For more information on RandR, please see the X.org RandR specification at
* http://cgit.freedesktop.org/xorg/proto/randrproto/tree/randrproto.txt
* (take your time to read it completely, it answers all questions).
*
*/
#include "all.h"
#include <time.h>
#include <xcb/randr.h>
/* While a clean namespace is usually a pretty good thing, we really need
* to use shorter names than the whole xcb_randr_* default names. */
typedef xcb_randr_get_crtc_info_reply_t crtc_info;
typedef xcb_randr_get_screen_resources_current_reply_t resources_reply;
/* Pointer to the result of the query for primary output */
xcb_randr_get_output_primary_reply_t *primary;
/* Stores all outputs available in your current session. */
struct outputs_head outputs = TAILQ_HEAD_INITIALIZER(outputs);
static bool randr_disabled = false;
/*
* Get a specific output by its internal X11 id. Used by randr_query_outputs
* to check if the output is new (only in the first scan) or if we are
* re-scanning.
*
*/
static Output *get_output_by_id(xcb_randr_output_t id) {
Output *output;
TAILQ_FOREACH(output, &outputs, outputs)
if (output->id == id)
return output;
return NULL;
}
/*
* Returns the output with the given name if it is active (!) or NULL.
*
*/
Output *get_output_by_name(const char *name) {
Output *output;
TAILQ_FOREACH(output, &outputs, outputs)
if (output->active &&
strcasecmp(output->name, name) == 0)
return output;
return NULL;
}
/*
* Returns the first output which is active.
*
*/
Output *get_first_output(void) {
Output *output;
TAILQ_FOREACH(output, &outputs, outputs)
if (output->active)
return output;
die("No usable outputs available.\n");
}
/*
* Returns the active (!) output which contains the coordinates x, y or NULL
* if there is no output which contains these coordinates.
*
*/
Output *get_output_containing(int x, int y) {
Output *output;
TAILQ_FOREACH(output, &outputs, outputs) {
if (!output->active)
continue;
DLOG("comparing x=%d y=%d with x=%d and y=%d width %d height %d\n",
x, y, output->rect.x, output->rect.y, output->rect.width, output->rect.height);
if (x >= output->rect.x && x < (output->rect.x + output->rect.width) &&
y >= output->rect.y && y < (output->rect.y + output->rect.height))
return output;
}
return NULL;
}
/*
* Gets the output which is the last one in the given direction, for example
* the output on the most bottom when direction == D_DOWN, the output most
* right when direction == D_RIGHT and so on.
*
* This function always returns a output.
*
*/
Output *get_output_most(direction_t direction, Output *current) {
Output *best = get_output_next(direction, current, FARTHEST_OUTPUT);
if (!best)
best = current;
DLOG("current = %s, best = %s\n", current->name, best->name);
return best;
}
/*
* Gets the output which is the next one in the given direction.
*
*/
Output *get_output_next(direction_t direction, Output *current, output_close_far_t close_far) {
Rect *cur = &(current->rect),
*other;
Output *output,
*best = NULL;
TAILQ_FOREACH(output, &outputs, outputs) {
if (!output->active)
continue;
other = &(output->rect);
if ((direction == D_RIGHT && other->x > cur->x) ||
(direction == D_LEFT && other->x < cur->x)) {
/* Skip the output when it doesnt overlap the other ones y
* coordinate at all. */
if ((other->y + other->height) <= cur->y ||
(cur->y + cur->height) <= other->y)
continue;
} else if ((direction == D_DOWN && other->y > cur->y) ||
(direction == D_UP && other->y < cur->y)) {
/* Skip the output when it doesnt overlap the other ones x
* coordinate at all. */
if ((other->x + other->width) <= cur->x ||
(cur->x + cur->width) <= other->x)
continue;
} else
continue;
/* No candidate yet? Start with this one. */
if (!best) {
best = output;
continue;
}
if (close_far == CLOSEST_OUTPUT) {
/* Is this output better (closer to the current output) than our
* current best bet? */
if ((direction == D_RIGHT && other->x < best->rect.x) ||
(direction == D_LEFT && other->x > best->rect.x) ||
(direction == D_DOWN && other->y < best->rect.y) ||
(direction == D_UP && other->y > best->rect.y)) {
best = output;
continue;
}
} else {
/* Is this output better (farther to the current output) than our
* current best bet? */
if ((direction == D_RIGHT && other->x > best->rect.x) ||
(direction == D_LEFT && other->x < best->rect.x) ||
(direction == D_DOWN && other->y > best->rect.y) ||
(direction == D_UP && other->y < best->rect.y)) {
best = output;
continue;
}
}
}
DLOG("current = %s, best = %s\n", current->name, (best ? best->name : "NULL"));
return best;
}
/*
* Disables RandR support by creating exactly one output with the size of the
* X11 screen.
*
*/
void disable_randr(xcb_connection_t *conn) {
DLOG("RandR extension unusable, disabling.\n");
Output *s = scalloc(sizeof(Output));
s->active = true;
s->rect.x = 0;
s->rect.y = 0;
s->rect.width = root_screen->width_in_pixels;
s->rect.height = root_screen->height_in_pixels;
s->name = "xroot-0";
output_init_con(s);
init_ws_for_output(s, output_get_content(s->con));
TAILQ_INSERT_TAIL(&outputs, s, outputs);
randr_disabled = true;
}
/*
* Initializes a CT_OUTPUT Con (searches existing ones from inplace restart
* before) to use for the given Output.
*
*/
void output_init_con(Output *output) {
Con *con = NULL, *current;
bool reused = false;
DLOG("init_con for output %s\n", output->name);
/* Search for a Con with that name directly below the root node. There
* might be one from a restored layout. */
TAILQ_FOREACH(current, &(croot->nodes_head), nodes) {
if (strcmp(current->name, output->name) != 0)
continue;
con = current;
reused = true;
DLOG("Using existing con %p / %s\n", con, con->name);
break;
}
if (con == NULL) {
con = con_new(croot, NULL);
FREE(con->name);
con->name = sstrdup(output->name);
con->type = CT_OUTPUT;
con->layout = L_OUTPUT;
con_fix_percent(croot);
}
con->rect = output->rect;
output->con = con;
char *name;
sasprintf(&name, "[i3 con] output %s", con->name);
x_set_name(con, name);
FREE(name);
if (reused) {
DLOG("Not adding workspace, this was a reused con\n");
return;
}
DLOG("Changing layout, adding top/bottom dockarea\n");
Con *topdock = con_new(NULL, NULL);
topdock->type = CT_DOCKAREA;
topdock->layout = L_DOCKAREA;
/* this container swallows dock clients */
Match *match = scalloc(sizeof(Match));
match_init(match);
match->dock = M_DOCK_TOP;
match->insert_where = M_BELOW;
TAILQ_INSERT_TAIL(&(topdock->swallow_head), match, matches);
FREE(topdock->name);
topdock->name = sstrdup("topdock");
sasprintf(&name, "[i3 con] top dockarea %s", con->name);
x_set_name(topdock, name);
FREE(name);
DLOG("attaching\n");
con_attach(topdock, con, false);
/* content container */
DLOG("adding main content container\n");
Con *content = con_new(NULL, NULL);
content->type = CT_CON;
content->layout = L_SPLITH;
FREE(content->name);
content->name = sstrdup("content");
sasprintf(&name, "[i3 con] content %s", con->name);
x_set_name(content, name);
FREE(name);
con_attach(content, con, false);
/* bottom dock container */
Con *bottomdock = con_new(NULL, NULL);
bottomdock->type = CT_DOCKAREA;
bottomdock->layout = L_DOCKAREA;
/* this container swallows dock clients */
match = scalloc(sizeof(Match));
match_init(match);
match->dock = M_DOCK_BOTTOM;
match->insert_where = M_BELOW;
TAILQ_INSERT_TAIL(&(bottomdock->swallow_head), match, matches);
FREE(bottomdock->name);
bottomdock->name = sstrdup("bottomdock");
sasprintf(&name, "[i3 con] bottom dockarea %s", con->name);
x_set_name(bottomdock, name);
FREE(name);
DLOG("attaching\n");
con_attach(bottomdock, con, false);
}
/*
* Initializes at least one workspace for this output, trying the following
* steps until there is at least one workspace:
*
* • Move existing workspaces, which are assigned to be on the given output, to
* the output.
* • Create the first assigned workspace for this output.
* • Create the first unused workspace.
*
*/
void init_ws_for_output(Output *output, Con *content) {
/* go through all assignments and move the existing workspaces to this output */
struct Workspace_Assignment *assignment;
TAILQ_FOREACH(assignment, &ws_assignments, ws_assignments) {
if (strcmp(assignment->output, output->name) != 0)
continue;
/* check if this workspace actually exists */
Con *workspace = NULL, *out;
TAILQ_FOREACH(out, &(croot->nodes_head), nodes)
GREP_FIRST(workspace, output_get_content(out),
!strcasecmp(child->name, assignment->name));
if (workspace == NULL)
continue;
/* check that this workspace is not already attached (that means the
* user configured this assignment twice) */
Con *workspace_out = con_get_output(workspace);
if (workspace_out == output->con) {
LOG("Workspace \"%s\" assigned to output \"%s\", but it is already "
"there. Do you have two assignment directives for the same "
"workspace in your configuration file?\n",
workspace->name, output->name);
continue;
}
/* if so, move it over */
LOG("Moving workspace \"%s\" from output \"%s\" to \"%s\" due to assignment\n",
workspace->name, workspace_out->name, output->name);
/* if the workspace is currently visible on that output, we need to
* switch to a different workspace - otherwise the output would end up
* with no active workspace */
bool visible = workspace_is_visible(workspace);
Con *previous = NULL;
if (visible && (previous = TAILQ_NEXT(workspace, focused))) {
LOG("Switching to previously used workspace \"%s\" on output \"%s\"\n",
previous->name, workspace_out->name);
workspace_show(previous);
}
/* Render the output on which the workspace was to get correct Rects.
* Then, we need to work with the "content" container, since we cannot
* be sure that the workspace itself was rendered at all (in case its
* invisible, it wont be rendered). */
render_con(workspace_out, false);
Con *ws_out_content = output_get_content(workspace_out);
Con *floating_con;
TAILQ_FOREACH(floating_con, &(workspace->floating_head), floating_windows)
/* NB: We use output->con here because content is not yet rendered,
* so it has a rect of {0, 0, 0, 0}. */
floating_fix_coordinates(floating_con, &(ws_out_content->rect), &(output->con->rect));
con_detach(workspace);
con_attach(workspace, content, false);
/* In case the workspace we just moved was visible but there was no
* other workspace to switch to, we need to initialize the source
* output aswell */
if (visible && previous == NULL) {
LOG("There is no workspace left on \"%s\", re-initializing\n",
workspace_out->name);
init_ws_for_output(get_output_by_name(workspace_out->name),
output_get_content(workspace_out));
DLOG("Done re-initializing, continuing with \"%s\"\n", output->name);
}
}
/* if a workspace exists, we are done now */
if (!TAILQ_EMPTY(&(content->nodes_head))) {
/* ensure that one of the workspaces is actually visible (in fullscreen
* mode), if they were invisible before, this might not be the case. */
Con *visible = NULL;
GREP_FIRST(visible, content, child->fullscreen_mode == CF_OUTPUT);
if (!visible) {
visible = TAILQ_FIRST(&(content->nodes_head));
focused = content;
workspace_show(visible);
}
return;
}
/* otherwise, we create the first assigned ws for this output */
TAILQ_FOREACH(assignment, &ws_assignments, ws_assignments) {
if (strcmp(assignment->output, output->name) != 0)
continue;
LOG("Initializing first assigned workspace \"%s\" for output \"%s\"\n",
assignment->name, assignment->output);
focused = content;
workspace_show_by_name(assignment->name);
return;
}
/* if there is still no workspace, we create the first free workspace */
DLOG("Now adding a workspace\n");
Con *ws = create_workspace_on_output(output, content);
/* TODO: Set focus in main.c */
con_focus(ws);
}
/*
* This function needs to be called when changing the mode of an output when
* it already has some workspaces (or a bar window) assigned.
*
* It reconfigures the bar window for the new mode, copies the new rect into
* each workspace on this output and forces all windows on the affected
* workspaces to be reconfigured.
*
* It is necessary to call render_layout() afterwards.
*
*/
static void output_change_mode(xcb_connection_t *conn, Output *output) {
DLOG("Output mode changed, updating rect\n");
assert(output->con != NULL);
output->con->rect = output->rect;
Con *content, *workspace, *child;
/* Point content to the container of the workspaces */
content = output_get_content(output->con);
/* Fix the position of all floating windows on this output.
* The 'rect' of each workspace will be updated in src/render.c. */
TAILQ_FOREACH(workspace, &(content->nodes_head), nodes) {
TAILQ_FOREACH(child, &(workspace->floating_head), floating_windows) {
floating_fix_coordinates(child, &(workspace->rect), &(output->con->rect));
}
}
/* If default_orientation is NO_ORIENTATION, we change the orientation of
* the workspaces and their childs depending on output resolution. This is
* only done for workspaces with maximum one child. */
if (config.default_orientation == NO_ORIENTATION) {
TAILQ_FOREACH(workspace, &(content->nodes_head), nodes) {
/* Workspaces with more than one child are left untouched because
* we do not want to change an existing layout. */
if (con_num_children(workspace) > 1)
continue;
workspace->layout = (output->rect.height > output->rect.width) ? L_SPLITV : L_SPLITH;
DLOG("Setting workspace [%d,%s]'s layout to %d.\n", workspace->num, workspace->name, workspace->layout);
if ((child = TAILQ_FIRST(&(workspace->nodes_head)))) {
if (child->layout == L_SPLITV || child->layout == L_SPLITH)
child->layout = workspace->layout;
DLOG("Setting child [%d,%s]'s layout to %d.\n", child->num, child->name, child->layout);
}
}
}
}
/*
* Gets called by randr_query_outputs() for each output. The function adds new
* outputs to the list of outputs, checks if the mode of existing outputs has
* been changed or if an existing output has been disabled. It will then change
* either the "changed" or the "to_be_deleted" flag of the output, if
* appropriate.
*
*/
static void handle_output(xcb_connection_t *conn, xcb_randr_output_t id,
xcb_randr_get_output_info_reply_t *output,
xcb_timestamp_t cts, resources_reply *res) {
/* each CRT controller has a position in which we are interested in */
crtc_info *crtc;
Output *new = get_output_by_id(id);
bool existing = (new != NULL);
if (!existing)
new = scalloc(sizeof(Output));
new->id = id;
new->primary = (primary && primary->output == id);
FREE(new->name);
sasprintf(&new->name, "%.*s",
xcb_randr_get_output_info_name_length(output),
xcb_randr_get_output_info_name(output));
DLOG("found output with name %s\n", new->name);
/* Even if no CRTC is used at the moment, we store the output so that
* we do not need to change the list ever again (we only update the
* position/size) */
if (output->crtc == XCB_NONE) {
if (!existing) {
if (new->primary)
TAILQ_INSERT_HEAD(&outputs, new, outputs);
else TAILQ_INSERT_TAIL(&outputs, new, outputs);
} else if (new->active)
new->to_be_disabled = true;
return;
}
xcb_randr_get_crtc_info_cookie_t icookie;
icookie = xcb_randr_get_crtc_info(conn, output->crtc, cts);
if ((crtc = xcb_randr_get_crtc_info_reply(conn, icookie, NULL)) == NULL) {
DLOG("Skipping output %s: could not get CRTC (%p)\n",
new->name, crtc);
free(new);
return;
}
bool updated = update_if_necessary(&(new->rect.x), crtc->x) |
update_if_necessary(&(new->rect.y), crtc->y) |
update_if_necessary(&(new->rect.width), crtc->width) |
update_if_necessary(&(new->rect.height), crtc->height);
free(crtc);
new->active = (new->rect.width != 0 && new->rect.height != 0);
if (!new->active) {
DLOG("width/height 0/0, disabling output\n");
return;
}
DLOG("mode: %dx%d+%d+%d\n", new->rect.width, new->rect.height,
new->rect.x, new->rect.y);
/* If we dont need to change an existing output or if the output
* does not exist in the first place, the case is simple: we either
* need to insert the new output or we are done. */
if (!updated || !existing) {
if (!existing) {
if (new->primary)
TAILQ_INSERT_HEAD(&outputs, new, outputs);
else TAILQ_INSERT_TAIL(&outputs, new, outputs);
}
return;
}
new->changed = true;
}
/*
* (Re-)queries the outputs via RandR and stores them in the list of outputs.
*
*/
void randr_query_outputs(void) {
Output *output, *other, *first;
xcb_randr_get_output_primary_cookie_t pcookie;
xcb_randr_get_screen_resources_current_cookie_t rcookie;
resources_reply *res;
/* timestamp of the configuration so that we get consistent replies to all
* requests (if the configuration changes between our different calls) */
xcb_timestamp_t cts;
/* an output is VGA-1, LVDS-1, etc. (usually physical video outputs) */
xcb_randr_output_t *randr_outputs;
if (randr_disabled)
return;
/* Get screen resources (primary output, crtcs, outputs, modes) */
rcookie = xcb_randr_get_screen_resources_current(conn, root);
pcookie = xcb_randr_get_output_primary(conn, root);
if ((primary = xcb_randr_get_output_primary_reply(conn, pcookie, NULL)) == NULL)
ELOG("Could not get RandR primary output\n");
else DLOG("primary output is %08x\n", primary->output);
if ((res = xcb_randr_get_screen_resources_current_reply(conn, rcookie, NULL)) == NULL) {
disable_randr(conn);
return;
}
cts = res->config_timestamp;
int len = xcb_randr_get_screen_resources_current_outputs_length(res);
randr_outputs = xcb_randr_get_screen_resources_current_outputs(res);
/* Request information for each output */
xcb_randr_get_output_info_cookie_t ocookie[len];
for (int i = 0; i < len; i++)
ocookie[i] = xcb_randr_get_output_info(conn, randr_outputs[i], cts);
/* Loop through all outputs available for this X11 screen */
for (int i = 0; i < len; i++) {
xcb_randr_get_output_info_reply_t *output;
if ((output = xcb_randr_get_output_info_reply(conn, ocookie[i], NULL)) == NULL)
continue;
handle_output(conn, randr_outputs[i], output, cts, res);
free(output);
}
/* Check for clones, disable the clones and reduce the mode to the
* lowest common mode */
TAILQ_FOREACH(output, &outputs, outputs) {
if (!output->active || output->to_be_disabled)
continue;
DLOG("output %p / %s, position (%d, %d), checking for clones\n",
output, output->name, output->rect.x, output->rect.y);
for (other = output;
other != TAILQ_END(&outputs);
other = TAILQ_NEXT(other, outputs)) {
if (other == output || !other->active || other->to_be_disabled)
continue;
if (other->rect.x != output->rect.x ||
other->rect.y != output->rect.y)
continue;
DLOG("output %p has the same position, his mode = %d x %d\n",
other, other->rect.width, other->rect.height);
uint32_t width = min(other->rect.width, output->rect.width);
uint32_t height = min(other->rect.height, output->rect.height);
if (update_if_necessary(&(output->rect.width), width) |
update_if_necessary(&(output->rect.height), height))
output->changed = true;
update_if_necessary(&(other->rect.width), width);
update_if_necessary(&(other->rect.height), height);
DLOG("disabling output %p (%s)\n", other, other->name);
other->to_be_disabled = true;
DLOG("new output mode %d x %d, other mode %d x %d\n",
output->rect.width, output->rect.height,
other->rect.width, other->rect.height);
}
}
/* Ensure that all outputs which are active also have a con. This is
* necessary because in the next step, a clone might get disabled. Example:
* LVDS1 active, VGA1 gets activated as a clone of LVDS1 (has no con).
* LVDS1 gets disabled. */
TAILQ_FOREACH(output, &outputs, outputs) {
if (output->active && output->con == NULL) {
DLOG("Need to initialize a Con for output %s\n", output->name);
output_init_con(output);
output->changed = false;
}
}
/* Handle outputs which have a new mode or are disabled now (either
* because the user disabled them or because they are clones) */
TAILQ_FOREACH(output, &outputs, outputs) {
if (output->to_be_disabled) {
output->active = false;
DLOG("Output %s disabled, re-assigning workspaces/docks\n", output->name);
first = get_first_output();
/* TODO: refactor the following code into a nice function. maybe
* use an on_destroy callback which is implement differently for
* different container types (CT_CONTENT vs. CT_DOCKAREA)? */
Con *first_content = output_get_content(first->con);
if (output->con != NULL) {
/* We need to move the workspaces from the disappearing output to the first output */
/* 1: Get the con to focus next, if the disappearing ws is focused */
Con *next = NULL;
if (TAILQ_FIRST(&(croot->focus_head)) == output->con) {
DLOG("This output (%p) was focused! Getting next\n", output->con);
next = focused;
DLOG("next = %p\n", next);
}
/* 2: iterate through workspaces and re-assign them, fixing the coordinates
* of floating containers as we go */
Con *current;
Con *old_content = output_get_content(output->con);
while (!TAILQ_EMPTY(&(old_content->nodes_head))) {
current = TAILQ_FIRST(&(old_content->nodes_head));
if (current != next && TAILQ_EMPTY(&(current->focus_head))) {
/* the workspace is empty and not focused, get rid of it */
DLOG("Getting rid of current = %p / %s (empty, unfocused)\n", current, current->name);
tree_close(current, DONT_KILL_WINDOW, false, false);
continue;
}
DLOG("Detaching current = %p / %s\n", current, current->name);
con_detach(current);
DLOG("Re-attaching current = %p / %s\n", current, current->name);
con_attach(current, first_content, false);
DLOG("Fixing the coordinates of floating containers\n");
Con *floating_con;
TAILQ_FOREACH(floating_con, &(current->floating_head), floating_windows)
floating_fix_coordinates(floating_con, &(output->con->rect), &(first->con->rect));
DLOG("Done, next\n");
}
DLOG("re-attached all workspaces\n");
if (next) {
DLOG("now focusing next = %p\n", next);
con_focus(next);
workspace_show(con_get_workspace(next));
}
/* 3: move the dock clients to the first output */
Con *child;
TAILQ_FOREACH(child, &(output->con->nodes_head), nodes) {
if (child->type != CT_DOCKAREA)
continue;
DLOG("Handling dock con %p\n", child);
Con *dock;
while (!TAILQ_EMPTY(&(child->nodes_head))) {
dock = TAILQ_FIRST(&(child->nodes_head));
Con *nc;
Match *match;
nc = con_for_window(first->con, dock->window, &match);
DLOG("Moving dock client %p to nc %p\n", dock, nc);
con_detach(dock);
DLOG("Re-attaching\n");
con_attach(dock, nc, false);
DLOG("Done\n");
}
}
DLOG("destroying disappearing con %p\n", output->con);
tree_close(output->con, DONT_KILL_WINDOW, true, false);
DLOG("Done. Should be fine now\n");
output->con = NULL;
}
output->to_be_disabled = false;
output->changed = false;
}
if (output->changed) {
output_change_mode(conn, output);
output->changed = false;
}
}
if (TAILQ_EMPTY(&outputs)) {
ELOG("No outputs found via RandR, disabling\n");
disable_randr(conn);
}
/* Verifies that there is at least one active output as a side-effect. */
get_first_output();
/* Just go through each active output and assign one workspace */
TAILQ_FOREACH(output, &outputs, outputs) {
if (!output->active)
continue;
Con *content = output_get_content(output->con);
if (!TAILQ_EMPTY(&(content->nodes_head)))
continue;
DLOG("Should add ws for output %s\n", output->name);
init_ws_for_output(output, content);
}
/* Focus the primary screen, if possible */
TAILQ_FOREACH(output, &outputs, outputs) {
if (!output->primary || !output->con)
continue;
DLOG("Focusing primary output %s\n", output->name);
con_focus(con_descend_focused(output->con));
}
/* render_layout flushes */
tree_render();
FREE(res);
FREE(primary);
}
/*
* We have just established a connection to the X server and need the initial
* XRandR information to setup workspaces for each screen.
*
*/
void randr_init(int *event_base) {
const xcb_query_extension_reply_t *extreply;
extreply = xcb_get_extension_data(conn, &xcb_randr_id);
if (!extreply->present) {
disable_randr(conn);
return;
} else randr_query_outputs();
if (event_base != NULL)
*event_base = extreply->first_event;
xcb_randr_select_input(conn, root,
XCB_RANDR_NOTIFY_MASK_SCREEN_CHANGE |
XCB_RANDR_NOTIFY_MASK_OUTPUT_CHANGE |
XCB_RANDR_NOTIFY_MASK_CRTC_CHANGE |
XCB_RANDR_NOTIFY_MASK_OUTPUT_PROPERTY);
xcb_flush(conn);
}