mutter/src/wayland/meta-wayland-touch.c
Olivier Fourdan 20bb8bf502 wayland: Avoid a race in wl_seat capabilities
The way wl_seat capabilities work, by notifying clients of capabilities
changes, and clients consequently requesting the relevant interface
objects (pointer, keyboard, touch) is inherently racy.

On quick VT changes for example, capabilities on the seat will be added
and removed, and by the time the client receives the capability change
notification and requests the relevant keyboard, pointer or touch,
another VT switch might have occurred and the wl_pointer, wl_keyboard or
wl_touch already destroyed, leading to a protocol error which kills the
client.

To avoid this, create the objects when requested regardless of the
capabilities.

Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1797
Related: https://bugzilla.gnome.org/show_bug.cgi?id=790932
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/77>
2021-09-16 06:52:20 +00:00

609 lines
16 KiB
C

/*
* Wayland Support
*
* Copyright (C) 2014 Red Hat
*
* 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, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
* 02111-1307, USA.
*
* Author: Carlos Garnacho <carlosg@gnome.org>
*/
#include "config.h"
#include <glib.h>
#include <string.h>
#include "compositor/meta-surface-actor-wayland.h"
#include "wayland/meta-wayland-private.h"
G_DEFINE_TYPE (MetaWaylandTouch, meta_wayland_touch,
META_TYPE_WAYLAND_INPUT_DEVICE)
struct _MetaWaylandTouchSurface
{
MetaWaylandSurface *surface;
MetaWaylandTouch *touch;
struct wl_listener surface_destroy_listener;
struct wl_list resource_list;
gint touch_count;
};
struct _MetaWaylandTouchInfo
{
MetaWaylandTouchSurface *touch_surface;
guint32 slot_serial;
gint32 slot;
gfloat start_x;
gfloat start_y;
gfloat x;
gfloat y;
guint updated : 1;
guint begin_delivered : 1;
};
static void
move_resources (struct wl_list *destination, struct wl_list *source)
{
wl_list_insert_list (destination, source);
wl_list_init (source);
}
static void
move_resources_for_client (struct wl_list *destination,
struct wl_list *source,
struct wl_client *client)
{
struct wl_resource *resource, *tmp;
wl_resource_for_each_safe (resource, tmp, source)
{
if (wl_resource_get_client (resource) == client)
{
wl_list_remove (wl_resource_get_link (resource));
wl_list_insert (destination, wl_resource_get_link (resource));
}
}
}
static void
touch_surface_free (gpointer data)
{
MetaWaylandTouchSurface *touch_surface = data;
MetaWaylandTouch *touch = touch_surface->touch;
move_resources (&touch->resource_list,
&touch_surface->resource_list);
wl_list_remove (&touch_surface->surface_destroy_listener.link);
g_free (touch_surface);
}
static MetaWaylandTouchSurface *
touch_surface_increment_touch (MetaWaylandTouchSurface *surface)
{
surface->touch_count++;
return surface;
}
static void
touch_surface_decrement_touch (MetaWaylandTouchSurface *touch_surface)
{
touch_surface->touch_count--;
if (touch_surface->touch_count == 0)
{
/* Now that there are no touches on the surface, free the
* MetaWaylandTouchSurface, the memory is actually owned by
* the touch_surface->touch_surfaces hashtable, so remove the
* item from there.
*/
MetaWaylandTouch *touch = touch_surface->touch;
g_hash_table_remove (touch->touch_surfaces, touch_surface->surface);
}
}
static void
touch_handle_surface_destroy (struct wl_listener *listener, void *data)
{
MetaWaylandTouchSurface *touch_surface = wl_container_of (listener, touch_surface, surface_destroy_listener);
MetaWaylandSurface *surface = touch_surface->surface;
MetaWaylandTouch *touch = touch_surface->touch;
MetaWaylandTouchInfo *touch_info;
GHashTableIter iter;
g_hash_table_iter_init (&iter, touch->touches);
/* Destroy all touches on the surface, this indirectly drops touch_count
* on the touch_surface to 0, also freeing touch_surface and removing
* from the touch_surfaces hashtable.
*/
while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &touch_info))
{
if (touch_info->touch_surface == touch_surface)
g_hash_table_iter_remove (&iter);
}
/* Ensure the surface no longer exists */
g_assert (g_hash_table_remove (touch->touch_surfaces, surface) == FALSE);
}
static MetaWaylandTouchSurface *
touch_surface_get (MetaWaylandTouch *touch,
MetaWaylandSurface *surface)
{
MetaWaylandTouchSurface *touch_surface;
touch_surface = g_hash_table_lookup (touch->touch_surfaces, surface);
if (touch_surface)
return touch_surface_increment_touch (touch_surface);
/* Create a new one for this surface */
touch_surface = g_new0 (MetaWaylandTouchSurface, 1);
touch_surface->touch = touch;
touch_surface->surface = surface;
touch_surface->touch_count = 1;
touch_surface->surface_destroy_listener.notify = touch_handle_surface_destroy;
wl_resource_add_destroy_listener (touch_surface->surface->resource,
&touch_surface->surface_destroy_listener);
wl_list_init (&touch_surface->resource_list);
move_resources_for_client (&touch_surface->resource_list,
&touch->resource_list,
wl_resource_get_client (touch_surface->surface->resource));
g_hash_table_insert (touch->touch_surfaces, surface, touch_surface);
return touch_surface;
}
static MetaWaylandTouchInfo *
touch_get_info (MetaWaylandTouch *touch,
ClutterEventSequence *sequence,
gboolean create)
{
MetaWaylandTouchInfo *touch_info;
touch_info = g_hash_table_lookup (touch->touches, sequence);
if (!touch_info && create)
{
touch_info = g_new0 (MetaWaylandTouchInfo, 1);
touch_info->slot = clutter_event_sequence_get_slot (sequence);
g_hash_table_insert (touch->touches, sequence, touch_info);
}
return touch_info;
}
static void
touch_get_relative_coordinates (MetaWaylandTouch *touch,
MetaWaylandSurface *surface,
const ClutterEvent *event,
gfloat *x,
gfloat *y)
{
gfloat event_x, event_y;
clutter_event_get_coords (event, &event_x, &event_y);
return meta_wayland_surface_get_relative_coordinates (surface,
event_x, event_y,
x, y);
}
void
meta_wayland_touch_update (MetaWaylandTouch *touch,
const ClutterEvent *event)
{
MetaWaylandTouchInfo *touch_info;
ClutterEventSequence *sequence;
sequence = clutter_event_get_event_sequence (event);
if (event->type == CLUTTER_TOUCH_BEGIN)
{
MetaWaylandSurface *surface = NULL;
ClutterActor *actor;
actor = clutter_event_get_source (event);
if (META_IS_SURFACE_ACTOR_WAYLAND (actor))
surface = meta_surface_actor_wayland_get_surface (META_SURFACE_ACTOR_WAYLAND (actor));
if (!surface)
return;
touch_info = touch_get_info (touch, sequence, TRUE);
touch_info->touch_surface = touch_surface_get (touch, surface);
clutter_event_get_coords (event, &touch_info->start_x, &touch_info->start_y);
}
else
touch_info = touch_get_info (touch, sequence, FALSE);
if (!touch_info)
return;
if (event->type != CLUTTER_TOUCH_BEGIN &&
!touch_info->begin_delivered)
{
g_hash_table_remove (touch->touches, sequence);
return;
}
if (event->type == CLUTTER_TOUCH_BEGIN ||
event->type == CLUTTER_TOUCH_END)
{
MetaWaylandInputDevice *input_device = META_WAYLAND_INPUT_DEVICE (touch);
touch_info->slot_serial =
meta_wayland_input_device_next_serial (input_device);
}
touch_get_relative_coordinates (touch, touch_info->touch_surface->surface,
event, &touch_info->x, &touch_info->y);
touch_info->updated = TRUE;
}
static void
handle_touch_begin (MetaWaylandTouch *touch,
const ClutterEvent *event)
{
MetaWaylandTouchInfo *touch_info;
ClutterEventSequence *sequence;
struct wl_resource *resource;
struct wl_list *l;
sequence = clutter_event_get_event_sequence (event);
touch_info = touch_get_info (touch, sequence, FALSE);
if (!touch_info)
return;
l = &touch_info->touch_surface->resource_list;
wl_resource_for_each(resource, l)
{
wl_touch_send_down (resource, touch_info->slot_serial,
clutter_event_get_time (event),
touch_info->touch_surface->surface->resource,
touch_info->slot,
wl_fixed_from_double (touch_info->x),
wl_fixed_from_double (touch_info->y));
}
touch_info->begin_delivered = TRUE;
}
static void
handle_touch_update (MetaWaylandTouch *touch,
const ClutterEvent *event)
{
MetaWaylandTouchInfo *touch_info;
ClutterEventSequence *sequence;
struct wl_resource *resource;
struct wl_list *l;
sequence = clutter_event_get_event_sequence (event);
touch_info = touch_get_info (touch, sequence, FALSE);
if (!touch_info)
return;
l = &touch_info->touch_surface->resource_list;
wl_resource_for_each(resource, l)
{
wl_touch_send_motion (resource,
clutter_event_get_time (event),
touch_info->slot,
wl_fixed_from_double (touch_info->x),
wl_fixed_from_double (touch_info->y));
}
}
static void
handle_touch_end (MetaWaylandTouch *touch,
const ClutterEvent *event)
{
MetaWaylandTouchInfo *touch_info;
ClutterEventSequence *sequence;
struct wl_resource *resource;
struct wl_list *l;
sequence = clutter_event_get_event_sequence (event);
touch_info = touch_get_info (touch, sequence, FALSE);
if (!touch_info)
return;
l = &touch_info->touch_surface->resource_list;
wl_resource_for_each (resource, l)
{
wl_touch_send_up (resource, touch_info->slot_serial,
clutter_event_get_time (event),
touch_info->slot);
}
g_hash_table_remove (touch->touches, sequence);
}
static GList *
touch_get_surfaces (MetaWaylandTouch *touch,
gboolean only_updated)
{
MetaWaylandTouchInfo *touch_info;
GList *surfaces = NULL;
GHashTableIter iter;
g_hash_table_iter_init (&iter, touch->touches);
while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &touch_info))
{
if (only_updated && !touch_info->updated)
continue;
if (g_list_find (surfaces, touch_info->touch_surface))
continue;
surfaces = g_list_prepend (surfaces, touch_info->touch_surface);
touch_info->updated = FALSE;
}
return g_list_reverse (surfaces);
}
static void
touch_send_frame_event (MetaWaylandTouch *touch)
{
GList *surfaces, *s;
surfaces = touch_get_surfaces (touch, TRUE);
for (s = surfaces; s; s = s->next)
{
MetaWaylandTouchSurface *touch_surface = s->data;
struct wl_resource *resource;
struct wl_list *l;
l = &touch_surface->resource_list;
wl_resource_for_each(resource, l)
{
wl_touch_send_frame (resource);
}
}
g_list_free (surfaces);
}
static gboolean
queue_frame_event_cb (MetaWaylandTouch *touch)
{
touch_send_frame_event (touch);
touch->queued_frame_id = 0;
return G_SOURCE_REMOVE;
}
static void
send_or_queue_frame_event (MetaWaylandTouch *touch)
{
if (clutter_events_pending ())
{
if (touch->queued_frame_id == 0)
{
touch->queued_frame_id =
g_idle_add_full (CLUTTER_PRIORITY_EVENTS + 1,
(GSourceFunc) queue_frame_event_cb,
touch, NULL);
}
}
else
{
/* There's no more events */
g_clear_handle_id (&touch->queued_frame_id, g_source_remove);
touch_send_frame_event (touch);
}
}
gboolean
meta_wayland_touch_handle_event (MetaWaylandTouch *touch,
const ClutterEvent *event)
{
switch (event->type)
{
case CLUTTER_TOUCH_BEGIN:
handle_touch_begin (touch, event);
break;
case CLUTTER_TOUCH_UPDATE:
handle_touch_update (touch, event);
break;
case CLUTTER_TOUCH_END:
handle_touch_end (touch, event);
break;
case CLUTTER_TOUCH_CANCEL:
meta_wayland_touch_cancel (touch);
break;
default:
return FALSE;
}
send_or_queue_frame_event (touch);
return FALSE;
}
static void
unbind_resource (struct wl_resource *resource)
{
wl_list_remove (wl_resource_get_link (resource));
}
static void
touch_release (struct wl_client *client,
struct wl_resource *resource)
{
wl_resource_destroy (resource);
}
static const struct wl_touch_interface touch_interface = {
touch_release,
};
static void
touch_info_free (MetaWaylandTouchInfo *touch_info)
{
touch_surface_decrement_touch (touch_info->touch_surface);
g_free (touch_info);
}
void
meta_wayland_touch_cancel (MetaWaylandTouch *touch)
{
MetaWaylandInputDevice *input_device = META_WAYLAND_INPUT_DEVICE (touch);
MetaWaylandSeat *seat = meta_wayland_input_device_get_seat (input_device);
GList *surfaces, *s;
if (!meta_wayland_seat_has_touch (seat))
return;
surfaces = s = touch_get_surfaces (touch, FALSE);
for (s = surfaces; s; s = s->next)
{
MetaWaylandTouchSurface *touch_surface = s->data;
struct wl_resource *resource;
struct wl_list *l;
l = &touch_surface->resource_list;
wl_resource_for_each(resource, l)
wl_touch_send_cancel (resource);
}
g_hash_table_remove_all (touch->touches);
g_list_free (surfaces);
}
void
meta_wayland_touch_enable (MetaWaylandTouch *touch)
{
touch->touch_surfaces = g_hash_table_new_full (NULL, NULL, NULL,
(GDestroyNotify) touch_surface_free);
touch->touches = g_hash_table_new_full (NULL, NULL, NULL,
(GDestroyNotify) touch_info_free);
wl_list_init (&touch->resource_list);
}
void
meta_wayland_touch_disable (MetaWaylandTouch *touch)
{
meta_wayland_touch_cancel (touch);
g_clear_pointer (&touch->touch_surfaces, g_hash_table_unref);
g_clear_pointer (&touch->touches, g_hash_table_unref);
}
void
meta_wayland_touch_create_new_resource (MetaWaylandTouch *touch,
struct wl_client *client,
struct wl_resource *seat_resource,
uint32_t id)
{
struct wl_resource *cr;
cr = wl_resource_create (client, &wl_touch_interface, wl_resource_get_version (seat_resource), id);
wl_resource_set_implementation (cr, &touch_interface, touch, unbind_resource);
wl_list_insert (&touch->resource_list, wl_resource_get_link (cr));
}
gboolean
meta_wayland_touch_can_popup (MetaWaylandTouch *touch,
uint32_t serial)
{
MetaWaylandTouchInfo *touch_info;
GHashTableIter iter;
if (!touch->touches)
return FALSE;
g_hash_table_iter_init (&iter, touch->touches);
while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &touch_info))
{
if (touch_info->slot_serial == serial)
return TRUE;
}
return FALSE;
}
ClutterEventSequence *
meta_wayland_touch_find_grab_sequence (MetaWaylandTouch *touch,
MetaWaylandSurface *surface,
uint32_t serial)
{
MetaWaylandTouchInfo *touch_info;
ClutterEventSequence *sequence;
GHashTableIter iter;
if (!touch->touches)
return NULL;
g_hash_table_iter_init (&iter, touch->touches);
while (g_hash_table_iter_next (&iter, (gpointer*) &sequence,
(gpointer*) &touch_info))
{
if (touch_info->slot_serial == serial &&
touch_info->touch_surface->surface == surface)
return sequence;
}
return NULL;
}
gboolean
meta_wayland_touch_get_press_coords (MetaWaylandTouch *touch,
ClutterEventSequence *sequence,
gfloat *x,
gfloat *y)
{
MetaWaylandTouchInfo *touch_info;
if (!touch->touches)
return FALSE;
touch_info = g_hash_table_lookup (touch->touches, sequence);
if (!touch_info)
return FALSE;
if (x)
*x = touch_info->start_x;
if (y)
*y = touch_info->start_y;
return TRUE;
}
static void
meta_wayland_touch_init (MetaWaylandTouch *touch)
{
}
static void
meta_wayland_touch_class_init (MetaWaylandTouchClass *klass)
{
}