i3/src/xinerama.c
Michael Stapelberg 16d33ec9df Bugfix: Correctly re-assign dock_clients to the first screen when their screen disappears
This could lead to a null-pointer dereference when closing dock
clients that got lost.
2009-10-28 15:37:34 +01:00

438 lines
17 KiB
C

/*
* vim:ts=8:expandtab
*
* i3 - an improved dynamic tiling window manager
*
* © 2009 Michael Stapelberg and contributors
*
* See file LICENSE for license information.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <assert.h>
#include <time.h>
#include <xcb/xcb.h>
#include <xcb/xinerama.h>
#include "queue.h"
#include "i3.h"
#include "data.h"
#include "table.h"
#include "util.h"
#include "xinerama.h"
#include "layout.h"
#include "xcb.h"
#include "config.h"
#include "workspace.h"
/* This TAILQ of i3Screens stores the virtual screens, used for handling overlapping screens
* (xrandr --same-as) */
struct screens_head *virtual_screens;
static bool xinerama_enabled = true;
/*
* Returns true if both screen objects describe the same screen (checks their
* size and position).
*
*/
bool screens_are_equal(i3Screen *screen1, i3Screen *screen2) {
/* If one of both objects (or both) are NULL, we cannot compare them */
if (screen1 == NULL || screen2 == NULL)
return false;
/* If the pointers are equal, take the short-circuit */
if (screen1 == screen2)
return true;
/* Compare their size - other properties are not relevant to determine
* if a screen is equal to another one */
return (memcmp(&(screen1->rect), &(screen2->rect), sizeof(Rect)) == 0);
}
/*
* Looks in virtual_screens for the i3Screen whose start coordinates are x, y
*
*/
i3Screen *get_screen_at(int x, int y, struct screens_head *screenlist) {
i3Screen *screen;
TAILQ_FOREACH(screen, screenlist, screens)
if (screen->rect.x == x && screen->rect.y == y)
return screen;
return NULL;
}
/*
* Looks in virtual_screens for the i3Screen which contains coordinates x, y
*
*/
i3Screen *get_screen_containing(int x, int y) {
i3Screen *screen;
TAILQ_FOREACH(screen, virtual_screens, screens) {
LOG("comparing x=%d y=%d with x=%d and y=%d width %d height %d\n",
x, y, screen->rect.x, screen->rect.y, screen->rect.width, screen->rect.height);
if (x >= screen->rect.x && x < (screen->rect.x + screen->rect.width) &&
y >= screen->rect.y && y < (screen->rect.y + screen->rect.height))
return screen;
}
return NULL;
}
/*
* Gets the screen which is the last one in the given direction, for example the screen
* on the most bottom when direction == D_DOWN, the screen most right when direction == D_RIGHT
* and so on.
*
* This function always returns a screen.
*
*/
i3Screen *get_screen_most(direction_t direction, i3Screen *current) {
i3Screen *screen, *candidate = NULL;
int position = 0;
TAILQ_FOREACH(screen, virtual_screens, screens) {
/* Repeated calls of WIN determine the winner of the comparison */
#define WIN(variable, condition) \
if (variable condition) { \
candidate = screen; \
position = variable; \
} \
break;
if (((direction == D_UP) || (direction == D_DOWN)) &&
(current->rect.x != screen->rect.x))
continue;
if (((direction == D_LEFT) || (direction == D_RIGHT)) &&
(current->rect.y != screen->rect.y))
continue;
switch (direction) {
case D_UP:
WIN(screen->rect.y, <= position);
case D_DOWN:
WIN(screen->rect.y, >= position);
case D_LEFT:
WIN(screen->rect.x, <= position);
case D_RIGHT:
WIN(screen->rect.x, >= position);
}
}
assert(candidate != NULL);
return candidate;
}
static void initialize_screen(xcb_connection_t *conn, i3Screen *screen, Workspace *workspace) {
i3Font *font = load_font(conn, config.font);
workspace->screen = screen;
screen->current_workspace = workspace;
/* Create a bar for each screen */
Rect bar_rect = {screen->rect.x,
screen->rect.y + screen->rect.height - (font->height + 6),
screen->rect.x + screen->rect.width,
font->height + 6};
uint32_t mask = XCB_CW_OVERRIDE_REDIRECT | XCB_CW_EVENT_MASK;
uint32_t values[] = {1, XCB_EVENT_MASK_EXPOSURE | XCB_EVENT_MASK_BUTTON_PRESS};
screen->bar = create_window(conn, bar_rect, XCB_WINDOW_CLASS_INPUT_OUTPUT, XCB_CURSOR_LEFT_PTR, true, mask, values);
screen->bargc = xcb_generate_id(conn);
xcb_create_gc(conn, screen->bargc, screen->bar, 0, 0);
SLIST_INIT(&(screen->dock_clients));
LOG("that is virtual screen at %d x %d with %d x %d\n",
screen->rect.x, screen->rect.y, screen->rect.width, screen->rect.height);
}
/*
* Fills virtual_screens with exactly one screen with width/height of the whole X server.
*
*/
static void disable_xinerama(xcb_connection_t *conn) {
xcb_screen_t *root_screen = xcb_setup_roots_iterator(xcb_get_setup(conn)).data;
i3Screen *s = calloc(sizeof(i3Screen), 1);
s->rect.x = 0;
s->rect.y = 0;
s->rect.width = root_screen->width_in_pixels;
s->rect.height = root_screen->height_in_pixels;
num_screens = 1;
s->num = 0;
TAILQ_INSERT_TAIL(virtual_screens, s, screens);
xinerama_enabled = false;
}
/*
* Gets the Xinerama screens and converts them to virtual i3Screens (only one screen for two
* Xinerama screen which are configured in clone mode) in the given screenlist
*
*/
static void query_screens(xcb_connection_t *conn, struct screens_head *screenlist) {
xcb_xinerama_query_screens_reply_t *reply;
xcb_xinerama_screen_info_t *screen_info;
time_t before_trying = time(NULL);
/* Try repeatedly to find screens (there might be short timeframes in
* which the X server does not return any screens, such as when rotating
* screens), but not longer than 5 seconds (strictly speaking, only four
* seconds of trying are guaranteed due to the 1-second-resolution) */
while ((time(NULL) - before_trying) < 5) {
reply = xcb_xinerama_query_screens_reply(conn, xcb_xinerama_query_screens_unchecked(conn), NULL);
if (!reply) {
LOG("Couldn't get Xinerama screens\n");
return;
}
screen_info = xcb_xinerama_query_screens_screen_info(reply);
int screens = xcb_xinerama_query_screens_screen_info_length(reply);
num_screens = 0;
for (int screen = 0; screen < screens; screen++) {
i3Screen *s = get_screen_at(screen_info[screen].x_org, screen_info[screen].y_org, screenlist);
if (s != NULL) {
/* This screen already exists. We use the littlest screen so that the user
can always see the complete workspace */
s->rect.width = min(s->rect.width, screen_info[screen].width);
s->rect.height = min(s->rect.height, screen_info[screen].height);
} else {
s = calloc(sizeof(i3Screen), 1);
s->rect.x = screen_info[screen].x_org;
s->rect.y = screen_info[screen].y_org;
s->rect.width = screen_info[screen].width;
s->rect.height = screen_info[screen].height;
/* We always treat the screen at 0x0 as the primary screen */
if (s->rect.x == 0 && s->rect.y == 0)
TAILQ_INSERT_HEAD(screenlist, s, screens);
else TAILQ_INSERT_TAIL(screenlist, s, screens);
num_screens++;
}
LOG("found Xinerama screen: %d x %d at %d x %d\n",
screen_info[screen].width, screen_info[screen].height,
screen_info[screen].x_org, screen_info[screen].y_org);
}
free(reply);
if (num_screens == 0) {
LOG("No screens found. This is weird. Trying again...\n");
continue;
}
break;
}
}
/*
* We have just established a connection to the X server and need the initial Xinerama
* information to setup workspaces for each screen.
*
*/
void initialize_xinerama(xcb_connection_t *conn) {
virtual_screens = scalloc(sizeof(struct screens_head));
TAILQ_INIT(virtual_screens);
if (!xcb_get_extension_data(conn, &xcb_xinerama_id)->present) {
LOG("Xinerama extension not found, disabling.\n");
disable_xinerama(conn);
} else {
xcb_xinerama_is_active_reply_t *reply;
reply = xcb_xinerama_is_active_reply(conn, xcb_xinerama_is_active(conn), NULL);
if (reply == NULL || !reply->state) {
LOG("Xinerama is not active (in your X-Server), disabling.\n");
disable_xinerama(conn);
} else
query_screens(conn, virtual_screens);
FREE(reply);
}
i3Screen *screen;
num_screens = 0;
/* Just go through each workspace and associate as many screens as we can. */
TAILQ_FOREACH(screen, virtual_screens, screens) {
screen->num = num_screens;
num_screens++;
Workspace *ws = get_first_workspace_for_screen(virtual_screens, screen);
initialize_screen(conn, screen, ws);
}
}
/*
* This is called when the rootwindow receives a configure_notify event and therefore the
* number/position of the Xinerama screens could have changed.
*
*/
void xinerama_requery_screens(xcb_connection_t *conn) {
i3Font *font = load_font(conn, config.font);
/* POSSIBLE PROBLEM: Is the order of the Xinerama screens always constant? That is, can
it change when I move the --right-of video projector to --left-of? */
if (!xinerama_enabled) {
LOG("Xinerama is disabled\n");
return;
}
/* We use a separate copy to diff with the previous set of screens */
struct screens_head *new_screens = scalloc(sizeof(struct screens_head));
TAILQ_INIT(new_screens);
query_screens(conn, new_screens);
i3Screen *first = TAILQ_FIRST(new_screens),
*screen,
*old_screen;
int screen_count = 0;
/* Mark each workspace which currently is assigned to a screen, so we
* can garbage-collect afterwards */
Workspace *ws;
TAILQ_FOREACH(ws, workspaces, workspaces)
ws->reassigned = (ws->screen == NULL);
TAILQ_FOREACH(screen, new_screens, screens) {
screen->num = screen_count;
screen->current_workspace = NULL;
TAILQ_FOREACH(old_screen, virtual_screens, screens) {
if (old_screen->num != screen_count)
continue;
LOG("Found a matching screen\n");
/* Use the same workspace */
screen->current_workspace = old_screen->current_workspace;
/* Re-use the old bar window */
screen->bar = old_screen->bar;
screen->bargc = old_screen->bargc;
LOG("old_screen->bar = %p\n", old_screen->bar);
Rect bar_rect = {screen->rect.x,
screen->rect.y + screen->rect.height - (font->height + 6),
screen->rect.x + screen->rect.width,
font->height + 6};
LOG("configuring bar to be at %d x %d with %d x %d\n",
bar_rect.x, bar_rect.y, bar_rect.height, bar_rect.width);
xcb_configure_window(conn, screen->bar, XCB_CONFIG_WINDOW_X |
XCB_CONFIG_WINDOW_Y |
XCB_CONFIG_WINDOW_WIDTH |
XCB_CONFIG_WINDOW_HEIGHT, &(bar_rect.x));
/* Copy the list head for the dock clients */
screen->dock_clients = old_screen->dock_clients;
SLIST_INIT(&(old_screen->dock_clients));
/* Update the dimensions */
Workspace *ws;
TAILQ_FOREACH(ws, workspaces, workspaces) {
if (ws->screen != old_screen)
continue;
LOG("re-assigning ws %d\n", ws->num);
memcpy(&(ws->rect), &(screen->rect), sizeof(Rect));
ws->screen = screen;
ws->reassigned = true;
}
break;
}
if (screen->current_workspace == NULL) {
/* Find the first unused workspace, preferring the ones
* which are assigned to this screen and initialize
* the screen with it. */
LOG("getting first ws for screen %p\n", screen);
Workspace *ws = get_first_workspace_for_screen(new_screens, screen);
initialize_screen(conn, screen, ws);
ws->reassigned = true;
/* As this workspace just got visible (we got a new screen
* without workspace), we need to map its clients */
workspace_map_clients(conn, ws);
}
screen_count++;
}
/* check for dock_clients which are out of bounds */
TAILQ_FOREACH(old_screen, virtual_screens, screens) {
if (SLIST_EMPTY(&(old_screen->dock_clients)))
continue;
LOG("dock_clients out of bounds at screen %p, reassigning\n", old_screen);
if (SLIST_EMPTY(&(first->dock_clients))) {
first->dock_clients = old_screen->dock_clients;
continue;
}
/* We need to merge the lists */
Client *dock_client;
while (!SLIST_EMPTY(&(old_screen->dock_clients))) {
dock_client = SLIST_FIRST(&(old_screen->dock_clients));
SLIST_INSERT_HEAD(&(first->dock_clients), dock_client, dock_clients);
SLIST_REMOVE_HEAD(&(old_screen->dock_clients), dock_clients);
}
}
/* Check for workspaces which are out of bounds */
TAILQ_FOREACH(ws, workspaces, workspaces) {
if (ws->reassigned)
continue;
Client *client;
LOG("Closing bar window (%p)\n", ws->screen->bar);
xcb_destroy_window(conn, ws->screen->bar);
LOG("Workspace %d's screen out of bounds, assigning to first screen\n", ws->num + 1);
ws->screen = first;
memcpy(&(ws->rect), &(first->rect), sizeof(Rect));
/* Force reconfiguration for each client on that workspace */
FOR_TABLE(ws)
CIRCLEQ_FOREACH(client, &(ws->table[cols][rows]->clients), clients)
client->force_reconfigure = true;
/* Render the workspace to reconfigure the clients. However, they will be visible now, so… */
render_workspace(conn, first, ws);
/* …unless we want to see them at the moment, we should hide that workspace */
if (workspace_is_visible(ws))
continue;
workspace_unmap_clients(conn, ws);
if (c_ws == ws) {
LOG("Need to adjust c_ws...\n");
c_ws = first->current_workspace;
}
}
xcb_flush(conn);
/* Free the old list */
while (!TAILQ_EMPTY(virtual_screens)) {
screen = TAILQ_FIRST(virtual_screens);
TAILQ_REMOVE(virtual_screens, screen, screens);
free(screen);
}
free(virtual_screens);
virtual_screens = new_screens;
LOG("Current workspace is now: %d\n", first->current_workspace);
render_layout(conn);
}