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mutter-performance-source/src/core/stack.c
Jasper St. Pierre becce7afa0 stack: Fix a crasher from a buffer overrun
The code that restacks X11 windows at the end first tracks any
old windows we know about, and then handles any windows created.

It starts when it ended, and then walks forwards and then
back looking for the first X11 window it doesn't know about.
However, when there aren't any X11 windows, it flies off the end
of the array and starts looking through random memory.

When it finds the X11 window, it then goes through and then tries
to restack the remaining windows according to how we've sorted
them.

Unfortunately, META_WINDOW_CLIENT_TYPE_X11 is 0, which is quite
common in random memory we have lying around, so we enter that
path and then just crash.

Fix the buffer overrun by adding the proper bounds check to the
search.

You can easily reproduce this by opening a menu while bloatpad
is full-screen. Why it only crashes when full-screen and not
when a standard window, I have no idea.
2014-04-12 08:15:58 -07:00

2016 lines
57 KiB
C

/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
/*
* SECTION:stack
* @short_description: Which windows cover which other windows
*/
/*
* Copyright (C) 2001 Havoc Pennington
* Copyright (C) 2002, 2003 Red Hat, Inc.
* Copyright (C) 2004 Rob Adams
* Copyright (C) 2004, 2005 Elijah Newren
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include "stack.h"
#include "window-private.h"
#include <meta/errors.h>
#include "frame.h"
#include <meta/group.h>
#include <meta/prefs.h>
#include <meta/workspace.h>
#include <X11/Xatom.h>
#include "x11/group-private.h"
#define WINDOW_HAS_TRANSIENT_TYPE(w) \
(w->type == META_WINDOW_DIALOG || \
w->type == META_WINDOW_MODAL_DIALOG || \
w->type == META_WINDOW_TOOLBAR || \
w->type == META_WINDOW_MENU || \
w->type == META_WINDOW_UTILITY)
#define WINDOW_TRANSIENT_FOR_WHOLE_GROUP(w) \
((w->xtransient_for == None || \
w->transient_parent_is_root_window) && \
WINDOW_HAS_TRANSIENT_TYPE (w))
#define WINDOW_IN_STACK(w) (w->stack_position >= 0)
static void stack_sync_to_xserver (MetaStack *stack);
static void meta_window_set_stack_position_no_sync (MetaWindow *window,
int position);
static void stack_do_window_deletions (MetaStack *stack);
static void stack_do_window_additions (MetaStack *stack);
static void stack_do_relayer (MetaStack *stack);
static void stack_do_constrain (MetaStack *stack);
static void stack_do_resort (MetaStack *stack);
static void stack_ensure_sorted (MetaStack *stack);
MetaStack*
meta_stack_new (MetaScreen *screen)
{
MetaStack *stack;
stack = g_new (MetaStack, 1);
stack->screen = screen;
stack->xwindows = g_array_new (FALSE, FALSE, sizeof (Window));
stack->sorted = NULL;
stack->added = NULL;
stack->removed = NULL;
stack->freeze_count = 0;
stack->last_all_root_children_stacked = NULL;
stack->n_positions = 0;
stack->need_resort = FALSE;
stack->need_relayer = FALSE;
stack->need_constrain = FALSE;
return stack;
}
static void
free_last_all_root_children_stacked_cache (MetaStack *stack)
{
g_array_free (stack->last_all_root_children_stacked, TRUE);
stack->last_all_root_children_stacked = NULL;
}
void
meta_stack_free (MetaStack *stack)
{
g_array_free (stack->xwindows, TRUE);
g_list_free (stack->sorted);
g_list_free (stack->added);
g_list_free (stack->removed);
if (stack->last_all_root_children_stacked)
free_last_all_root_children_stacked_cache (stack);
g_free (stack);
}
void
meta_stack_add (MetaStack *stack,
MetaWindow *window)
{
meta_topic (META_DEBUG_STACK, "Adding window %s to the stack\n", window->desc);
if (window->stack_position >= 0)
meta_bug ("Window %s had stack position already\n", window->desc);
stack->added = g_list_prepend (stack->added, window);
window->stack_position = stack->n_positions;
stack->n_positions += 1;
meta_topic (META_DEBUG_STACK,
"Window %s has stack_position initialized to %d\n",
window->desc, window->stack_position);
stack_sync_to_xserver (stack);
meta_stack_update_window_tile_matches (stack, window->screen->active_workspace);
}
void
meta_stack_remove (MetaStack *stack,
MetaWindow *window)
{
meta_topic (META_DEBUG_STACK, "Removing window %s from the stack\n", window->desc);
if (window->stack_position < 0)
meta_bug ("Window %s removed from stack but had no stack position\n",
window->desc);
/* Set window to top position, so removing it will not leave gaps
* in the set of positions
*/
meta_window_set_stack_position_no_sync (window,
stack->n_positions - 1);
window->stack_position = -1;
stack->n_positions -= 1;
/* We don't know if it's been moved from "added" to "stack" yet */
stack->added = g_list_remove (stack->added, window);
stack->sorted = g_list_remove (stack->sorted, window);
/* Remember the window ID to remove it from the stack array.
* The macro is safe to use: Window is guaranteed to be 32 bits, and
* GUINT_TO_POINTER says it only works on 32 bits.
*/
stack->removed = g_list_prepend (stack->removed,
GUINT_TO_POINTER (window->xwindow));
if (window->frame)
stack->removed = g_list_prepend (stack->removed,
GUINT_TO_POINTER (window->frame->xwindow));
stack_sync_to_xserver (stack);
meta_stack_update_window_tile_matches (stack, window->screen->active_workspace);
}
void
meta_stack_update_layer (MetaStack *stack,
MetaWindow *window)
{
stack->need_relayer = TRUE;
stack_sync_to_xserver (stack);
meta_stack_update_window_tile_matches (stack, window->screen->active_workspace);
}
void
meta_stack_update_transient (MetaStack *stack,
MetaWindow *window)
{
stack->need_constrain = TRUE;
stack_sync_to_xserver (stack);
meta_stack_update_window_tile_matches (stack, window->screen->active_workspace);
}
/* raise/lower within a layer */
void
meta_stack_raise (MetaStack *stack,
MetaWindow *window)
{
GList *l;
int max_stack_position = window->stack_position;
MetaWorkspace *workspace;
stack_ensure_sorted (stack);
workspace = meta_window_get_workspace (window);
for (l = stack->sorted; l; l = l->next)
{
MetaWindow *w = (MetaWindow *) l->data;
if (meta_window_located_on_workspace (w, workspace) &&
w->stack_position > max_stack_position)
max_stack_position = w->stack_position;
}
if (max_stack_position == window->stack_position)
return;
meta_window_set_stack_position_no_sync (window, max_stack_position);
stack_sync_to_xserver (stack);
meta_stack_update_window_tile_matches (stack, window->screen->active_workspace);
}
void
meta_stack_lower (MetaStack *stack,
MetaWindow *window)
{
GList *l;
int min_stack_position = window->stack_position;
MetaWorkspace *workspace;
stack_ensure_sorted (stack);
workspace = meta_window_get_workspace (window);
for (l = stack->sorted; l; l = l->next)
{
MetaWindow *w = (MetaWindow *) l->data;
if (meta_window_located_on_workspace (w, workspace) &&
w->stack_position < min_stack_position)
min_stack_position = w->stack_position;
}
if (min_stack_position == window->stack_position)
return;
meta_window_set_stack_position_no_sync (window, min_stack_position);
stack_sync_to_xserver (stack);
meta_stack_update_window_tile_matches (stack, window->screen->active_workspace);
}
void
meta_stack_freeze (MetaStack *stack)
{
stack->freeze_count += 1;
}
void
meta_stack_thaw (MetaStack *stack)
{
g_return_if_fail (stack->freeze_count > 0);
stack->freeze_count -= 1;
stack_sync_to_xserver (stack);
meta_stack_update_window_tile_matches (stack, NULL);
}
void
meta_stack_update_window_tile_matches (MetaStack *stack,
MetaWorkspace *workspace)
{
GList *windows, *tmp;
if (stack->freeze_count > 0)
return;
windows = meta_stack_list_windows (stack, workspace);
tmp = windows;
while (tmp)
{
meta_window_compute_tile_match ((MetaWindow *) tmp->data);
tmp = tmp->next;
}
g_list_free (windows);
}
static gboolean
is_focused_foreach (MetaWindow *window,
void *data)
{
if (window->has_focus)
{
*((gboolean*) data) = TRUE;
return FALSE;
}
return TRUE;
}
static gboolean
windows_on_different_monitor (MetaWindow *a,
MetaWindow *b)
{
if (a->screen != b->screen)
return TRUE;
return meta_screen_get_monitor_for_window (a->screen, a) !=
meta_screen_get_monitor_for_window (b->screen, b);
}
/* Get layer ignoring any transient or group relationships */
static MetaStackLayer
get_standalone_layer (MetaWindow *window)
{
MetaStackLayer layer;
gboolean focused_transient = FALSE;
switch (window->type)
{
case META_WINDOW_DESKTOP:
layer = META_LAYER_DESKTOP;
break;
case META_WINDOW_DOCK:
/* still experimenting here */
if (window->wm_state_below)
layer = META_LAYER_BOTTOM;
else
layer = META_LAYER_DOCK;
break;
case META_WINDOW_DROPDOWN_MENU:
case META_WINDOW_POPUP_MENU:
case META_WINDOW_TOOLTIP:
case META_WINDOW_NOTIFICATION:
case META_WINDOW_COMBO:
case META_WINDOW_OVERRIDE_OTHER:
layer = META_LAYER_OVERRIDE_REDIRECT;
break;
default:
meta_window_foreach_transient (window,
is_focused_foreach,
&focused_transient);
if (window->wm_state_below)
layer = META_LAYER_BOTTOM;
else if (window->fullscreen &&
(focused_transient ||
window == window->display->focus_window ||
window->display->focus_window == NULL ||
(window->display->focus_window != NULL &&
windows_on_different_monitor (window,
window->display->focus_window))))
layer = META_LAYER_FULLSCREEN;
else if (window->wm_state_above && !META_WINDOW_MAXIMIZED (window))
layer = META_LAYER_TOP;
else
layer = META_LAYER_NORMAL;
break;
}
return layer;
}
/* Note that this function can never use window->layer only
* get_standalone_layer, or we'd have issues.
*/
static MetaStackLayer
get_maximum_layer_in_group (MetaWindow *window)
{
GSList *members;
MetaGroup *group;
GSList *tmp;
MetaStackLayer max;
MetaStackLayer layer;
max = META_LAYER_DESKTOP;
group = meta_window_get_group (window);
if (group != NULL)
members = meta_group_list_windows (group);
else
members = NULL;
tmp = members;
while (tmp != NULL)
{
MetaWindow *w = tmp->data;
if (!w->override_redirect)
{
layer = get_standalone_layer (w);
if (layer > max)
max = layer;
}
tmp = tmp->next;
}
g_slist_free (members);
return max;
}
static void
compute_layer (MetaWindow *window)
{
MetaStackLayer old_layer = window->layer;
window->layer = get_standalone_layer (window);
/* We can only do promotion-due-to-group for dialogs and other
* transients, or weird stuff happens like the desktop window and
* nautilus windows getting in the same layer, or all gnome-terminal
* windows getting in fullscreen layer if any terminal is
* fullscreen.
*/
if (window->layer != META_LAYER_DESKTOP &&
WINDOW_HAS_TRANSIENT_TYPE(window) &&
(window->xtransient_for == None ||
window->transient_parent_is_root_window))
{
/* We only do the group thing if the dialog is NOT transient for
* a particular window. Imagine a group with a normal window, a dock,
* and a dialog transient for the normal window; you don't want the dialog
* above the dock if it wouldn't normally be.
*/
MetaStackLayer group_max;
group_max = get_maximum_layer_in_group (window);
if (group_max > window->layer)
{
meta_topic (META_DEBUG_STACK,
"Promoting window %s from layer %u to %u due to group membership\n",
window->desc, window->layer, group_max);
window->layer = group_max;
}
}
meta_topic (META_DEBUG_STACK, "Window %s on layer %u type = %u has_focus = %d\n",
window->desc, window->layer,
window->type, window->has_focus);
if (window->layer != old_layer &&
(old_layer == META_LAYER_FULLSCREEN || window->layer == META_LAYER_FULLSCREEN))
meta_screen_queue_check_fullscreen (window->screen);
}
/* Front of the layer list is the topmost window,
* so the lower stack position is later in the list
*/
static int
compare_window_position (void *a,
void *b)
{
MetaWindow *window_a = a;
MetaWindow *window_b = b;
/* Go by layer, then stack_position */
if (window_a->layer < window_b->layer)
return 1; /* move window_a later in list */
else if (window_a->layer > window_b->layer)
return -1;
else if (window_a->stack_position < window_b->stack_position)
return 1; /* move window_a later in list */
else if (window_a->stack_position > window_b->stack_position)
return -1;
else
return 0; /* not reached */
}
/*
* Stacking constraints
*
* Assume constraints of the form "AB" meaning "window A must be
* below window B"
*
* If we have windows stacked from bottom to top
* "ABC" then raise A we get "BCA". Say C is
* transient for B is transient for A. So
* we have constraints AB and BC.
*
* After raising A, we need to reapply the constraints.
* If we do this by raising one window at a time -
*
* start: BCA
* apply AB: CAB
* apply BC: ABC
*
* but apply constraints in the wrong order and it breaks:
*
* start: BCA
* apply BC: BCA
* apply AB: CAB
*
* We make a directed graph of the constraints by linking
* from "above windows" to "below windows as follows:
*
* AB -> BC -> CD
* \
* CE
*
* If we then walk that graph and apply the constraints in the order
* that they appear, we will apply them correctly. Note that the
* graph MAY have cycles, so we have to guard against that.
*
*/
typedef struct Constraint Constraint;
struct Constraint
{
MetaWindow *above;
MetaWindow *below;
/* used to keep the constraint in the
* list of constraints for window "below"
*/
Constraint *next;
/* used to create the graph. */
GSList *next_nodes;
/* constraint has been applied, used
* to detect cycles.
*/
unsigned int applied : 1;
/* constraint has a previous node in the graph,
* used to find places to start in the graph.
* (I think this also has the side effect
* of preventing cycles, since cycles will
* have no starting point - so maybe
* the "applied" flag isn't needed.)
*/
unsigned int has_prev : 1;
};
/* We index the array of constraints by window
* stack positions, just because the stack
* positions are a convenient index.
*/
static void
add_constraint (Constraint **constraints,
MetaWindow *above,
MetaWindow *below)
{
Constraint *c;
g_assert (above->screen == below->screen);
/* check if constraint is a duplicate */
c = constraints[below->stack_position];
while (c != NULL)
{
if (c->above == above)
return;
c = c->next;
}
/* if not, add the constraint */
c = g_new (Constraint, 1);
c->above = above;
c->below = below;
c->next = constraints[below->stack_position];
c->next_nodes = NULL;
c->applied = FALSE;
c->has_prev = FALSE;
constraints[below->stack_position] = c;
}
static void
create_constraints (Constraint **constraints,
GList *windows)
{
GList *tmp;
tmp = windows;
while (tmp != NULL)
{
MetaWindow *w = tmp->data;
if (!WINDOW_IN_STACK (w))
{
meta_topic (META_DEBUG_STACK, "Window %s not in the stack, not constraining it\n",
w->desc);
tmp = tmp->next;
continue;
}
if (WINDOW_TRANSIENT_FOR_WHOLE_GROUP (w))
{
GSList *group_windows;
GSList *tmp2;
MetaGroup *group;
group = meta_window_get_group (w);
if (group != NULL)
group_windows = meta_group_list_windows (group);
else
group_windows = NULL;
tmp2 = group_windows;
while (tmp2 != NULL)
{
MetaWindow *group_window = tmp2->data;
if (!WINDOW_IN_STACK (group_window) ||
w->screen != group_window->screen ||
group_window->override_redirect)
{
tmp2 = tmp2->next;
continue;
}
#if 0
/* old way of doing it */
if (!(meta_window_is_ancestor_of_transient (w, group_window)) &&
!WINDOW_TRANSIENT_FOR_WHOLE_GROUP (group_window)) /* note */;/*note*/
#else
/* better way I think, so transient-for-group are constrained
* only above non-transient-type windows in their group
*/
if (!WINDOW_HAS_TRANSIENT_TYPE (group_window))
#endif
{
meta_topic (META_DEBUG_STACK, "Constraining %s above %s as it's transient for its group\n",
w->desc, group_window->desc);
add_constraint (constraints, w, group_window);
}
tmp2 = tmp2->next;
}
g_slist_free (group_windows);
}
else if (w->xtransient_for != None &&
!w->transient_parent_is_root_window)
{
MetaWindow *parent;
parent =
meta_display_lookup_x_window (w->display, w->xtransient_for);
if (parent && WINDOW_IN_STACK (parent) &&
parent->screen == w->screen)
{
meta_topic (META_DEBUG_STACK, "Constraining %s above %s due to transiency\n",
w->desc, parent->desc);
add_constraint (constraints, w, parent);
}
}
tmp = tmp->next;
}
}
static void
graph_constraints (Constraint **constraints,
int n_constraints)
{
int i;
i = 0;
while (i < n_constraints)
{
Constraint *c;
/* If we have "A below B" and "B below C" then AB -> BC so we
* add BC to next_nodes in AB.
*/
c = constraints[i];
while (c != NULL)
{
Constraint *n;
g_assert (c->below->stack_position == i);
/* Constraints where ->above is below are our
* next_nodes and we are their previous
*/
n = constraints[c->above->stack_position];
while (n != NULL)
{
c->next_nodes = g_slist_prepend (c->next_nodes,
n);
/* c is a previous node of n */
n->has_prev = TRUE;
n = n->next;
}
c = c->next;
}
++i;
}
}
static void
free_constraints (Constraint **constraints,
int n_constraints)
{
int i;
i = 0;
while (i < n_constraints)
{
Constraint *c;
c = constraints[i];
while (c != NULL)
{
Constraint *next = c->next;
g_slist_free (c->next_nodes);
g_free (c);
c = next;
}
++i;
}
}
static void
ensure_above (MetaWindow *above,
MetaWindow *below)
{
if (WINDOW_HAS_TRANSIENT_TYPE(above) &&
above->layer < below->layer)
{
meta_topic (META_DEBUG_STACK,
"Promoting window %s from layer %u to %u due to contraint\n",
above->desc, above->layer, below->layer);
above->layer = below->layer;
}
if (above->stack_position < below->stack_position)
{
/* move above to below->stack_position bumping below down the stack */
meta_window_set_stack_position_no_sync (above, below->stack_position);
g_assert (below->stack_position + 1 == above->stack_position);
}
meta_topic (META_DEBUG_STACK, "%s above at %d > %s below at %d\n",
above->desc, above->stack_position,
below->desc, below->stack_position);
}
static void
traverse_constraint (Constraint *c)
{
GSList *tmp;
if (c->applied)
return;
ensure_above (c->above, c->below);
c->applied = TRUE;
tmp = c->next_nodes;
while (tmp != NULL)
{
traverse_constraint (tmp->data);
tmp = tmp->next;
}
}
static void
apply_constraints (Constraint **constraints,
int n_constraints)
{
GSList *heads;
GSList *tmp;
int i;
/* List all heads in an ordered constraint chain */
heads = NULL;
i = 0;
while (i < n_constraints)
{
Constraint *c;
c = constraints[i];
while (c != NULL)
{
if (!c->has_prev)
heads = g_slist_prepend (heads, c);
c = c->next;
}
++i;
}
/* Now traverse the chain and apply constraints */
tmp = heads;
while (tmp != NULL)
{
Constraint *c = tmp->data;
traverse_constraint (c);
tmp = tmp->next;
}
g_slist_free (heads);
}
/**
* stack_do_window_deletions:
*
* Go through "deleted" and take the matching windows
* out of "windows".
*/
static void
stack_do_window_deletions (MetaStack *stack)
{
/* Do removals before adds, with paranoid idea that we might re-add
* the same window IDs.
*/
GList *tmp;
int i;
tmp = stack->removed;
while (tmp != NULL)
{
Window xwindow;
xwindow = GPOINTER_TO_UINT (tmp->data);
/* We go from the end figuring removals are more
* likely to be recent.
*/
i = stack->xwindows->len;
while (i > 0)
{
--i;
/* there's no guarantee we'll actually find windows to
* remove, e.g. the same xwindow could have been
* added/removed before we ever synced, and we put
* both the window->xwindow and window->frame->xwindow
* in the removal list.
*/
if (xwindow == g_array_index (stack->xwindows, Window, i))
{
g_array_remove_index (stack->xwindows, i);
goto next;
}
}
next:
tmp = tmp->next;
}
g_list_free (stack->removed);
stack->removed = NULL;
}
static void
stack_do_window_additions (MetaStack *stack)
{
GList *tmp;
gint i, n_added;
n_added = g_list_length (stack->added);
if (n_added > 0)
{
Window *end;
int old_size;
meta_topic (META_DEBUG_STACK,
"Adding %d windows to sorted list\n",
n_added);
old_size = stack->xwindows->len;
g_array_set_size (stack->xwindows, old_size + n_added);
end = &g_array_index (stack->xwindows, Window, old_size);
/* stack->added has the most recent additions at the
* front of the list, so we need to reverse it
*/
stack->added = g_list_reverse (stack->added);
i = 0;
tmp = stack->added;
while (tmp != NULL)
{
MetaWindow *w;
w = tmp->data;
end[i] = w->xwindow;
/* add to the main list */
stack->sorted = g_list_prepend (stack->sorted, w);
++i;
tmp = tmp->next;
}
stack->need_resort = TRUE; /* may not be needed as we add to top */
stack->need_constrain = TRUE;
stack->need_relayer = TRUE;
}
g_list_free (stack->added);
stack->added = NULL;
}
/**
* stack_do_relayer:
*
* Update the layers that windows are in
*/
static void
stack_do_relayer (MetaStack *stack)
{
GList *tmp;
if (!stack->need_relayer)
return;
meta_topic (META_DEBUG_STACK,
"Recomputing layers\n");
tmp = stack->sorted;
while (tmp != NULL)
{
MetaWindow *w;
MetaStackLayer old_layer;
w = tmp->data;
old_layer = w->layer;
compute_layer (w);
if (w->layer != old_layer)
{
meta_topic (META_DEBUG_STACK,
"Window %s moved from layer %u to %u\n",
w->desc, old_layer, w->layer);
stack->need_resort = TRUE;
stack->need_constrain = TRUE;
/* don't need to constrain as constraining
* purely operates in terms of stack_position
* not layer
*/
}
tmp = tmp->next;
}
stack->need_relayer = FALSE;
}
/**
* stack_do_constrain:
*
* Update stack_position and layer to reflect transiency
* constraints
*/
static void
stack_do_constrain (MetaStack *stack)
{
Constraint **constraints;
/* It'd be nice if this were all faster, probably */
if (!stack->need_constrain)
return;
meta_topic (META_DEBUG_STACK,
"Reapplying constraints\n");
constraints = g_new0 (Constraint*,
stack->n_positions);
create_constraints (constraints, stack->sorted);
graph_constraints (constraints, stack->n_positions);
apply_constraints (constraints, stack->n_positions);
free_constraints (constraints, stack->n_positions);
g_free (constraints);
stack->need_constrain = FALSE;
}
/**
* stack_do_resort:
*
* Sort stack->sorted with layers having priority over stack_position.
*/
static void
stack_do_resort (MetaStack *stack)
{
if (!stack->need_resort)
return;
meta_topic (META_DEBUG_STACK,
"Sorting stack list\n");
stack->sorted = g_list_sort (stack->sorted,
(GCompareFunc) compare_window_position);
stack->need_resort = FALSE;
}
/**
* stack_ensure_sorted:
*
* Puts the stack into canonical form.
*
* Honour the removed and added lists of the stack, and then recalculate
* all the layers (if the flag is set), re-run all the constraint calculations
* (if the flag is set), and finally re-sort the stack (if the flag is set,
* and if it wasn't already it might have become so during all the previous
* activity).
*/
static void
stack_ensure_sorted (MetaStack *stack)
{
stack_do_window_deletions (stack);
stack_do_window_additions (stack);
stack_do_relayer (stack);
stack_do_constrain (stack);
stack_do_resort (stack);
}
static MetaStackWindow *
find_top_most_managed_window (MetaScreen *screen,
const MetaStackWindow *ignore)
{
MetaStackTracker *stack_tracker = screen->stack_tracker;
MetaStackWindow *windows;
int n_windows;
int i;
meta_stack_tracker_get_stack (stack_tracker,
&windows, &n_windows);
/* Children are in order from bottom to top. We want to
* find the topmost managed child, then configure
* our window to be above it.
*/
for (i = n_windows -1; i >= 0; i--)
{
MetaStackWindow *other_window = &windows[i];
if (other_window->any.type == ignore->any.type &&
((other_window->any.type == META_WINDOW_CLIENT_TYPE_X11 &&
other_window->x11.xwindow == ignore->x11.xwindow) ||
other_window->wayland.meta_window == ignore->wayland.meta_window))
{
/* Do nothing. This means we're already the topmost managed
* window, but it DOES NOT mean we are already just above
* the topmost managed window. This is important because if
* an override redirect window is up, and we map a new
* managed window, the new window is probably above the old
* popup by default, and we want to push it below that
* popup. So keep looking for a sibling managed window
* to be moved below.
*/
}
else
{
if (other_window->any.type == META_WINDOW_CLIENT_TYPE_X11)
{
MetaWindow *other = meta_display_lookup_x_window (screen->display,
other_window->x11.xwindow);
if (other != NULL && !other->override_redirect)
return other_window;
}
else
{
/* All wayland windows are currently considered "managed"
* TODO: consider wayland pop-up windows like override
* redirect windows here. */
return other_window;
}
}
}
return NULL;
}
/* When moving an X window we sometimes need an X based sibling.
*
* If the given sibling is X based this function returns it back
* otherwise it searches downwards looking for the nearest X window.
*
* If no X based sibling could be found return NULL. */
static MetaStackWindow *
find_x11_sibling_downwards (MetaScreen *screen,
MetaStackWindow *sibling)
{
MetaStackTracker *stack_tracker = screen->stack_tracker;
MetaStackWindow *windows;
int n_windows;
int i;
if (sibling->any.type == META_WINDOW_CLIENT_TYPE_X11)
return sibling;
meta_stack_tracker_get_stack (stack_tracker,
&windows, &n_windows);
/* NB: Children are in order from bottom to top and we
* want to search downwards for the nearest X window.
*/
for (i = n_windows - 1; i >= 0; i--)
if (meta_stack_window_equal (&windows[i], sibling))
break;
for (; i >= 0; i--)
{
if (windows[i].any.type == META_WINDOW_CLIENT_TYPE_X11)
return &windows[i];
}
return NULL;
}
/**
* raise_window_relative_to_managed_windows:
*
* This function is used to avoid raising a window above popup
* menus and other such things.
*
* The key to the operation of this function is that we are expecting
* at most one window to be added at a time. If xwindow is newly added,
* then its own stack position will be too high (the frame window
* is created at the top of the stack), but if we ignore xwindow,
* then the *next* managed window in the stack will be a window that
* we've already stacked.
*
* We could generalize this and remove the assumption that windows
* are added one at a time by keeping an explicit ->stacked flag in
* MetaWindow.
*
* An alternate approach would be to reverse the stacking algorithm to
* work by placing each window above the others, and start by lowering
* a window to the bottom (instead of the current way, which works by
* placing each window below another and starting with a raise)
*/
static void
raise_window_relative_to_managed_windows (MetaScreen *screen,
const MetaStackWindow *window)
{
gulong serial = 0;
MetaStackWindow *sibling;
sibling = find_top_most_managed_window (screen, window);
if (!sibling)
{
if (window->any.type == META_WINDOW_CLIENT_TYPE_X11)
{
serial = XNextRequest (screen->display->xdisplay);
meta_error_trap_push (screen->display);
XLowerWindow (screen->display->xdisplay,
window->x11.xwindow);
meta_error_trap_pop (screen->display);
}
/* No sibling to use, just lower ourselves to the bottom
* to be sure we're below any override redirect windows.
*/
meta_stack_tracker_record_lower (screen->stack_tracker,
window,
serial);
return;
}
/* window is the topmost managed child */
meta_topic (META_DEBUG_STACK,
"Moving 0x%lx above topmost managed child window 0x%lx\n",
window->any.type == META_WINDOW_CLIENT_TYPE_X11 ? window->x11.xwindow: 0,
sibling->any.type == META_WINDOW_CLIENT_TYPE_X11 ? sibling->x11.xwindow: 0);
if (window->any.type == META_WINDOW_CLIENT_TYPE_X11)
{
XWindowChanges changes;
MetaStackWindow *x11_sibling = find_x11_sibling_downwards (screen, sibling);
serial = XNextRequest (screen->display->xdisplay);
if (x11_sibling)
{
changes.sibling = x11_sibling->x11.xwindow;
changes.stack_mode = Above;
meta_error_trap_push (screen->display);
XConfigureWindow (screen->display->xdisplay,
window->x11.xwindow,
CWSibling | CWStackMode,
&changes);
meta_error_trap_pop (screen->display);
}
else
{
/* No sibling to use, just lower ourselves to the bottom
* to be sure we're below any override redirect windows.
*/
meta_error_trap_push (screen->display);
XLowerWindow (screen->display->xdisplay,
window->x11.xwindow);
meta_error_trap_pop (screen->display);
}
}
meta_stack_tracker_record_raise_above (screen->stack_tracker,
window,
sibling,
serial);
}
/**
* stack_sync_to_server:
*
* Order the windows on the X server to be the same as in our structure.
* We do this using XRestackWindows if we don't know the previous order,
* or XConfigureWindow on a few particular windows if we do and can figure
* out the minimum set of changes. After that, we set __NET_CLIENT_LIST
* and __NET_CLIENT_LIST_STACKING.
*
* FIXME: Now that we have a good view of the stacking order on the server
* with MetaStackTracker it should be possible to do a simpler and better
* job of computing the minimal set of stacking requests needed.
*/
static void
stack_sync_to_xserver (MetaStack *stack)
{
GArray *x11_stacked;
GArray *x11_root_children_stacked;
GArray *all_root_children_stacked; /* wayland OR x11 */
GList *tmp;
GArray *x11_hidden;
GArray *x11_hidden_stack_windows;
int n_override_redirect = 0;
MetaStackWindow guard_stack_window;
/* Bail out if frozen */
if (stack->freeze_count > 0)
return;
meta_topic (META_DEBUG_STACK, "Syncing window stack to server\n");
stack_ensure_sorted (stack);
/* Create stacked xwindow arrays.
* Painfully, "stacked" is in bottom-to-top order for the
* _NET hints, and "root_children_stacked" is in top-to-bottom
* order for XRestackWindows()
*/
x11_stacked = g_array_new (FALSE, FALSE, sizeof (Window));
all_root_children_stacked = g_array_new (FALSE, FALSE, sizeof (MetaStackWindow));
x11_root_children_stacked = g_array_new (FALSE, FALSE, sizeof (Window));
x11_hidden_stack_windows = g_array_new (FALSE, FALSE, sizeof (MetaStackWindow));
x11_hidden = g_array_new (FALSE, FALSE, sizeof (Window));
/* The screen guard window sits above all hidden windows and acts as
* a barrier to input reaching these windows. */
g_array_append_val (x11_hidden, stack->screen->guard_window);
meta_topic (META_DEBUG_STACK, "Top to bottom: ");
meta_push_no_msg_prefix ();
for (tmp = stack->sorted; tmp != NULL; tmp = tmp->next)
{
MetaWindow *w = tmp->data;
Window top_level_window;
MetaStackWindow stack_window;
stack_window.any.type = w->client_type;
meta_topic (META_DEBUG_STACK, "%u:%d - %s ",
w->layer, w->stack_position, w->desc);
/* remember, stacked is in reverse order (bottom to top) */
if (w->override_redirect)
n_override_redirect++;
else
g_array_prepend_val (x11_stacked, w->xwindow);
if (w->frame)
top_level_window = w->frame->xwindow;
else
top_level_window = w->xwindow;
if (w->client_type == META_WINDOW_CLIENT_TYPE_X11)
stack_window.x11.xwindow = top_level_window;
else
stack_window.wayland.meta_window = w;
/* We don't restack hidden windows along with the rest, though they are
* reflected in the _NET hints. Hidden windows all get pushed below
* the screens fullscreen guard_window. */
if (w->hidden)
{
if (w->client_type == META_WINDOW_CLIENT_TYPE_X11)
{
MetaStackWindow stack_window;
stack_window.any.type = META_WINDOW_CLIENT_TYPE_X11;
stack_window.x11.xwindow = top_level_window;
g_array_append_val (x11_hidden_stack_windows, stack_window);
g_array_append_val (x11_hidden, top_level_window);
}
continue;
}
g_array_append_val (all_root_children_stacked, stack_window);
/* build XRestackWindows() array from top to bottom */
if (w->client_type == META_WINDOW_CLIENT_TYPE_X11)
g_array_append_val (x11_root_children_stacked, top_level_window);
}
meta_topic (META_DEBUG_STACK, "\n");
meta_pop_no_msg_prefix ();
/* All X windows should be in some stacking order */
if (x11_stacked->len != stack->xwindows->len - n_override_redirect)
meta_bug ("%u windows stacked, %u windows exist in stack\n",
x11_stacked->len, stack->xwindows->len);
/* Sync to server */
meta_topic (META_DEBUG_STACK, "Restacking %u windows\n",
all_root_children_stacked->len);
meta_error_trap_push (stack->screen->display);
if (stack->last_all_root_children_stacked == NULL)
{
/* Just impose our stack, we don't know the previous state.
* This involves a ton of circulate requests and may flicker.
*/
meta_topic (META_DEBUG_STACK, "Don't know last stack state, restacking everything\n");
if (all_root_children_stacked->len > 1)
{
gulong serial = 0;
if (x11_root_children_stacked->len > 1)
{
serial = XNextRequest (stack->screen->display->xdisplay);
XRestackWindows (stack->screen->display->xdisplay,
(Window *) x11_root_children_stacked->data,
x11_root_children_stacked->len);
}
meta_stack_tracker_record_restack_windows (stack->screen->stack_tracker,
(MetaStackWindow *) all_root_children_stacked->data,
all_root_children_stacked->len,
serial);
}
}
else if (all_root_children_stacked->len > 0)
{
/* Try to do minimal window moves to get the stack in order */
/* A point of note: these arrays include frames not client windows,
* so if a client window has changed frame since last_root_children_stacked
* was saved, then we may have inefficiency, but I don't think things
* break...
*/
const MetaStackWindow *old_stack = (MetaStackWindow *) stack->last_all_root_children_stacked->data;
const MetaStackWindow *new_stack = (MetaStackWindow *) all_root_children_stacked->data;
const int old_len = stack->last_all_root_children_stacked->len;
const int new_len = all_root_children_stacked->len;
const MetaStackWindow *oldp = old_stack;
const MetaStackWindow *newp = new_stack;
const MetaStackWindow *old_end = old_stack + old_len;
const MetaStackWindow *new_end = new_stack + new_len;
Window last_xwindow = None;
const MetaStackWindow *last_window = NULL;
while (oldp != old_end &&
newp != new_end)
{
if (meta_stack_window_equal (oldp, newp))
{
/* Stacks are the same here, move on */
++oldp;
if (newp->any.type == META_WINDOW_CLIENT_TYPE_X11)
last_xwindow = newp->x11.xwindow;
last_window = newp;
++newp;
}
else if ((oldp->any.type == META_WINDOW_CLIENT_TYPE_X11 &&
meta_display_lookup_x_window (stack->screen->display,
oldp->x11.xwindow) == NULL) ||
(oldp->any.type == META_WINDOW_CLIENT_TYPE_WAYLAND &&
oldp->wayland.meta_window == NULL))
{
/* *oldp is no longer known to us (probably destroyed),
* so we can just skip it
*/
++oldp;
}
else
{
/* Move *newp below the last_window */
if (!last_window)
{
meta_topic (META_DEBUG_STACK, "Using window 0x%lx as topmost (but leaving it in-place)\n",
newp->x11.xwindow);
raise_window_relative_to_managed_windows (stack->screen, newp);
}
else if (newp->any.type == META_WINDOW_CLIENT_TYPE_X11 &&
last_xwindow == None)
{
/* In this case we have an X window that we need to
* put below a wayland window and this is the
* topmost X window. */
/* In X terms (because this is the topmost X window)
* we want to
* raise_window_relative_to_managed_windows() to
* ensure the X window is below override-redirect
* pop-up windows.
*
* In Wayland terms we just want to ensure
* newp is lowered below last_window (which
* notably doesn't require an X request because we
* know last_window isn't an X window).
*/
raise_window_relative_to_managed_windows (stack->screen, newp);
meta_stack_tracker_record_lower_below (stack->screen->stack_tracker,
newp, last_window,
0); /* no x request serial */
}
else
{
gulong serial = 0;
/* This means that if last_xwindow is dead, but not
* *newp, then we fail to restack *newp; but on
* unmanaging last_xwindow, we'll fix it up.
*/
meta_topic (META_DEBUG_STACK, "Placing window 0x%lx below 0x%lx\n",
newp->any.type == META_WINDOW_CLIENT_TYPE_X11 ? newp->x11.xwindow : 0,
last_xwindow);
if (newp->any.type == META_WINDOW_CLIENT_TYPE_X11)
{
XWindowChanges changes;
serial = XNextRequest (stack->screen->display->xdisplay);
changes.sibling = last_xwindow;
changes.stack_mode = Below;
XConfigureWindow (stack->screen->display->xdisplay,
newp->x11.xwindow,
CWSibling | CWStackMode,
&changes);
}
meta_stack_tracker_record_lower_below (stack->screen->stack_tracker,
newp, last_window,
serial);
}
if (newp->any.type == META_WINDOW_CLIENT_TYPE_X11)
last_xwindow = newp->x11.xwindow;
last_window = newp;
++newp;
}
}
if (newp != new_end)
{
const MetaStackWindow *x_ref;
unsigned long serial = 0;
/* Restack remaining windows */
meta_topic (META_DEBUG_STACK, "Restacking remaining %d windows\n",
(int) (new_end - newp));
/* rewind until we find the last stacked X window that we can use
* as a reference point for re-stacking remaining X windows */
if (newp != new_stack)
for (x_ref = newp - 1;
x_ref->any.type != META_WINDOW_CLIENT_TYPE_X11 && x_ref > new_stack;
x_ref--)
;
else
x_ref = new_stack;
/* If we didn't find an X window looking backwards then walk forwards
* through the remaining windows to find the first remaining X window
* instead. */
if (x_ref->any.type != META_WINDOW_CLIENT_TYPE_X11)
{
for (x_ref = newp;
x_ref->any.type != META_WINDOW_CLIENT_TYPE_X11 && x_ref < new_end;
x_ref++)
;
}
/* If there are any X windows remaining unstacked then restack them */
if (x_ref->any.type == META_WINDOW_CLIENT_TYPE_X11)
{
int i;
for (i = x11_root_children_stacked->len - 1; i; i--)
{
Window *reference = &g_array_index (x11_root_children_stacked, Window, i);
if (*reference == x_ref->x11.xwindow)
{
int n = x11_root_children_stacked->len - i;
/* There's no point restacking if there's only one X window */
if (n == 1)
break;
serial = XNextRequest (stack->screen->display->xdisplay);
XRestackWindows (stack->screen->display->xdisplay,
reference, n);
break;
}
}
}
/* We need to include an already-stacked window
* in the restack call, so we get in the proper position
* with respect to it.
*/
if (newp != new_stack)
newp = MIN (newp - 1, x_ref);
meta_stack_tracker_record_restack_windows (stack->screen->stack_tracker,
newp, new_end - newp,
serial);
}
}
/* Push hidden X windows to the bottom of the stack under the guard window */
guard_stack_window.any.type = META_WINDOW_CLIENT_TYPE_X11;
guard_stack_window.x11.xwindow = stack->screen->guard_window;
meta_stack_tracker_record_lower (stack->screen->stack_tracker,
&guard_stack_window,
XNextRequest (stack->screen->display->xdisplay));
XLowerWindow (stack->screen->display->xdisplay, stack->screen->guard_window);
meta_stack_tracker_record_restack_windows (stack->screen->stack_tracker,
(MetaStackWindow *)x11_hidden_stack_windows->data,
x11_hidden_stack_windows->len,
XNextRequest (stack->screen->display->xdisplay));
XRestackWindows (stack->screen->display->xdisplay,
(Window *)x11_hidden->data,
x11_hidden->len);
g_array_free (x11_hidden, TRUE);
g_array_free (x11_hidden_stack_windows, TRUE);
meta_error_trap_pop (stack->screen->display);
/* on error, a window was destroyed; it should eventually
* get removed from the stacking list when we unmanage it
* and we'll fix stacking at that time.
*/
/* Sync _NET_CLIENT_LIST and _NET_CLIENT_LIST_STACKING */
XChangeProperty (stack->screen->display->xdisplay,
stack->screen->xroot,
stack->screen->display->atom__NET_CLIENT_LIST,
XA_WINDOW,
32, PropModeReplace,
(unsigned char *)stack->xwindows->data,
stack->xwindows->len);
XChangeProperty (stack->screen->display->xdisplay,
stack->screen->xroot,
stack->screen->display->atom__NET_CLIENT_LIST_STACKING,
XA_WINDOW,
32, PropModeReplace,
(unsigned char *)x11_stacked->data,
x11_stacked->len);
g_array_free (x11_stacked, TRUE);
if (stack->last_all_root_children_stacked)
free_last_all_root_children_stacked_cache (stack);
stack->last_all_root_children_stacked = all_root_children_stacked;
g_array_free (x11_root_children_stacked, TRUE);
/* That was scary... */
}
MetaWindow*
meta_stack_get_top (MetaStack *stack)
{
stack_ensure_sorted (stack);
if (stack->sorted)
return stack->sorted->data;
else
return NULL;
}
MetaWindow*
meta_stack_get_bottom (MetaStack *stack)
{
GList *link;
stack_ensure_sorted (stack);
link = g_list_last (stack->sorted);
if (link != NULL)
return link->data;
else
return NULL;
}
MetaWindow*
meta_stack_get_above (MetaStack *stack,
MetaWindow *window,
gboolean only_within_layer)
{
GList *link;
MetaWindow *above;
stack_ensure_sorted (stack);
link = g_list_find (stack->sorted, window);
if (link == NULL)
return NULL;
if (link->prev == NULL)
return NULL;
above = link->prev->data;
if (only_within_layer &&
above->layer != window->layer)
return NULL;
else
return above;
}
MetaWindow*
meta_stack_get_below (MetaStack *stack,
MetaWindow *window,
gboolean only_within_layer)
{
GList *link;
MetaWindow *below;
stack_ensure_sorted (stack);
link = g_list_find (stack->sorted, window);
if (link == NULL)
return NULL;
if (link->next == NULL)
return NULL;
below = link->next->data;
if (only_within_layer &&
below->layer != window->layer)
return NULL;
else
return below;
}
static gboolean
window_contains_point (MetaWindow *window,
int root_x,
int root_y)
{
MetaRectangle rect;
meta_window_get_frame_rect (window, &rect);
return POINT_IN_RECT (root_x, root_y, rect);
}
static MetaWindow*
get_default_focus_window (MetaStack *stack,
MetaWorkspace *workspace,
MetaWindow *not_this_one,
gboolean must_be_at_point,
int root_x,
int root_y)
{
/* Find the topmost, focusable, mapped, window.
* not_this_one is being unfocused or going away, so exclude it.
* Also, prefer to focus transient parent of not_this_one,
* or top window in same group as not_this_one.
*/
MetaWindow *transient_parent;
MetaWindow *topmost_in_group;
MetaWindow *topmost_overall;
MetaGroup *not_this_one_group;
GList *l;
transient_parent = NULL;
topmost_in_group = NULL;
topmost_overall = NULL;
if (not_this_one)
not_this_one_group = meta_window_get_group (not_this_one);
else
not_this_one_group = NULL;
stack_ensure_sorted (stack);
/* top of this layer is at the front of the list */
for (l = stack->sorted; l != NULL; l = l->next)
{
MetaWindow *window = l->data;
if (!window)
continue;
if (window == not_this_one)
continue;
if (window->unmaps_pending > 0)
continue;
if (window->minimized)
continue;
if (!(window->input || window->take_focus))
continue;
if (workspace != NULL && !meta_window_located_on_workspace (window, workspace))
continue;
if (must_be_at_point && !window_contains_point (window, root_x, root_y))
continue;
if (not_this_one != NULL)
{
if (transient_parent == NULL &&
meta_window_get_transient_for (not_this_one) == window)
transient_parent = window;
if (topmost_in_group == NULL &&
not_this_one_group != NULL &&
not_this_one_group == meta_window_get_group (window))
topmost_in_group = window;
}
if (topmost_overall == NULL && window->type != META_WINDOW_DOCK)
topmost_overall = window;
/* We could try to bail out early here for efficiency in
* some cases, but it's just not worth the code.
*/
}
if (transient_parent)
return transient_parent;
else if (topmost_in_group)
return topmost_in_group;
else if (topmost_overall)
return topmost_overall;
else
return NULL;
}
MetaWindow*
meta_stack_get_default_focus_window_at_point (MetaStack *stack,
MetaWorkspace *workspace,
MetaWindow *not_this_one,
int root_x,
int root_y)
{
return get_default_focus_window (stack, workspace, not_this_one,
TRUE, root_x, root_y);
}
MetaWindow*
meta_stack_get_default_focus_window (MetaStack *stack,
MetaWorkspace *workspace,
MetaWindow *not_this_one)
{
return get_default_focus_window (stack, workspace, not_this_one,
FALSE, 0, 0);
}
GList*
meta_stack_list_windows (MetaStack *stack,
MetaWorkspace *workspace)
{
GList *workspace_windows = NULL;
GList *link;
stack_ensure_sorted (stack); /* do adds/removes */
link = stack->sorted;
while (link)
{
MetaWindow *window = link->data;
if (window &&
(workspace == NULL || meta_window_located_on_workspace (window, workspace)))
{
workspace_windows = g_list_prepend (workspace_windows,
window);
}
link = link->next;
}
return workspace_windows;
}
int
meta_stack_windows_cmp (MetaStack *stack,
MetaWindow *window_a,
MetaWindow *window_b)
{
g_return_val_if_fail (window_a->screen == window_b->screen, 0);
/* -1 means a below b */
stack_ensure_sorted (stack); /* update constraints, layers */
if (window_a->layer < window_b->layer)
return -1;
else if (window_a->layer > window_b->layer)
return 1;
else if (window_a->stack_position < window_b->stack_position)
return -1;
else if (window_a->stack_position > window_b->stack_position)
return 1;
else
return 0; /* not reached */
}
static int
compare_just_window_stack_position (void *a,
void *b)
{
MetaWindow *window_a = a;
MetaWindow *window_b = b;
if (window_a->stack_position < window_b->stack_position)
return -1; /* move window_a earlier in list */
else if (window_a->stack_position > window_b->stack_position)
return 1;
else
return 0; /* not reached */
}
GList*
meta_stack_get_positions (MetaStack *stack)
{
GList *tmp;
/* Make sure to handle any adds or removes */
stack_ensure_sorted (stack);
tmp = g_list_copy (stack->sorted);
tmp = g_list_sort (tmp, (GCompareFunc) compare_just_window_stack_position);
return tmp;
}
static gint
compare_pointers (gconstpointer a,
gconstpointer b)
{
if (a > b)
return 1;
else if (a < b)
return -1;
else
return 0;
}
static gboolean
lists_contain_same_windows (GList *a,
GList *b)
{
GList *copy1, *copy2;
GList *tmp1, *tmp2;
if (g_list_length (a) != g_list_length (b))
return FALSE;
tmp1 = copy1 = g_list_sort (g_list_copy (a), compare_pointers);
tmp2 = copy2 = g_list_sort (g_list_copy (b), compare_pointers);
while (tmp1 && tmp1->data == tmp2->data) /* tmp2 is non-NULL if tmp1 is */
{
tmp1 = tmp1->next;
tmp2 = tmp2->next;
}
g_list_free (copy1);
g_list_free (copy2);
return (tmp1 == NULL); /* tmp2 is non-NULL if tmp1 is */
}
void
meta_stack_set_positions (MetaStack *stack,
GList *windows)
{
int i;
GList *tmp;
/* Make sure any adds or removes aren't in limbo -- is this needed? */
stack_ensure_sorted (stack);
if (!lists_contain_same_windows (windows, stack->sorted))
{
meta_warning ("This list of windows has somehow changed; not resetting "
"positions of the windows.\n");
return;
}
g_list_free (stack->sorted);
stack->sorted = g_list_copy (windows);
stack->need_resort = TRUE;
stack->need_constrain = TRUE;
i = 0;
tmp = windows;
while (tmp != NULL)
{
MetaWindow *w = tmp->data;
w->stack_position = i++;
tmp = tmp->next;
}
meta_topic (META_DEBUG_STACK,
"Reset the stack positions of (nearly) all windows\n");
stack_sync_to_xserver (stack);
meta_stack_update_window_tile_matches (stack, NULL);
}
void
meta_window_set_stack_position_no_sync (MetaWindow *window,
int position)
{
int low, high, delta;
GList *tmp;
g_return_if_fail (window->screen->stack != NULL);
g_return_if_fail (window->stack_position >= 0);
g_return_if_fail (position >= 0);
g_return_if_fail (position < window->screen->stack->n_positions);
if (position == window->stack_position)
{
meta_topic (META_DEBUG_STACK, "Window %s already has position %d\n",
window->desc, position);
return;
}
window->screen->stack->need_resort = TRUE;
window->screen->stack->need_constrain = TRUE;
if (position < window->stack_position)
{
low = position;
high = window->stack_position - 1;
delta = 1;
}
else
{
low = window->stack_position + 1;
high = position;
delta = -1;
}
tmp = window->screen->stack->sorted;
while (tmp != NULL)
{
MetaWindow *w = tmp->data;
if (w->stack_position >= low &&
w->stack_position <= high)
w->stack_position += delta;
tmp = tmp->next;
}
window->stack_position = position;
meta_topic (META_DEBUG_STACK,
"Window %s had stack_position set to %d\n",
window->desc, window->stack_position);
}
void
meta_window_set_stack_position (MetaWindow *window,
int position)
{
meta_window_set_stack_position_no_sync (window, position);
stack_sync_to_xserver (window->screen->stack);
meta_stack_update_window_tile_matches (window->screen->stack,
window->screen->active_workspace);
}