/* cairo - a vector graphics library with display and print output
*
* Copyright © 2002 University of Southern California
* Copyright © 2005 Red Hat, Inc.
* Copyright © 2009 Intel Corporation
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*
* The Original Code is the cairo graphics library.
*
* The Initial Developer of the Original Code is University of Southern
* California.
*
* Contributor(s):
* Carl D. Worth <cworth@cworth.org>
* Chris Wilson <chris@chris-wilson.co.uk>
*/
#include "cairoint.h"
#include "cairo-error-private.h"
#include "cairo-image-surface-private.h"
#include "cairo-surface-snapshot-inline.h"
static cairo_status_t
_cairo_surface_snapshot_finish (void *abstract_surface)
{
cairo_surface_snapshot_t *surface = abstract_surface;
cairo_status_t status = CAIRO_STATUS_SUCCESS;
TRACE ((stderr, "%s\n", __FUNCTION__));
if (surface->clone != NULL) {
cairo_surface_finish (surface->clone);
status = surface->clone->status;
cairo_surface_destroy (surface->clone);
}
CAIRO_MUTEX_FINI (surface->mutex);
return status;
}
static cairo_status_t
_cairo_surface_snapshot_flush (void *abstract_surface, unsigned flags)
{
cairo_surface_snapshot_t *surface = abstract_surface;
cairo_surface_t *target;
cairo_status_t status;
target = _cairo_surface_snapshot_get_target (&surface->base);
status = _cairo_surface_flush (target, flags);
cairo_surface_destroy (target);
return status;
}
static cairo_surface_t *
_cairo_surface_snapshot_source (void *abstract_surface,
cairo_rectangle_int_t *extents)
{
cairo_surface_snapshot_t *surface = abstract_surface;
return _cairo_surface_get_source (surface->target, extents); /* XXX racy */
}
struct snapshot_extra {
cairo_surface_t *target;
void *extra;
};
static cairo_status_t
_cairo_surface_snapshot_acquire_source_image (void *abstract_surface,
cairo_image_surface_t **image_out,
void **extra_out)
{
cairo_surface_snapshot_t *surface = abstract_surface;
struct snapshot_extra *extra;
cairo_status_t status;
extra = malloc (sizeof (*extra));
if (unlikely (extra == NULL))
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
extra->target = _cairo_surface_snapshot_get_target (&surface->base);
status = _cairo_surface_acquire_source_image (extra->target, image_out, &extra->extra);
if (unlikely (status)) {
cairo_surface_destroy (extra->target);
free (extra);
}
*extra_out = extra;
return status;
}
static void
_cairo_surface_snapshot_release_source_image (void *abstract_surface,
cairo_image_surface_t *image,
void *_extra)
{
struct snapshot_extra *extra = _extra;
_cairo_surface_release_source_image (extra->target, image, extra->extra);
cairo_surface_destroy (extra->target);
free (extra);
}
static cairo_bool_t
_cairo_surface_snapshot_get_extents (void *abstract_surface,
cairo_rectangle_int_t *extents)
{
cairo_surface_snapshot_t *surface = abstract_surface;
cairo_surface_t *target;
cairo_bool_t bounded;
target = _cairo_surface_snapshot_get_target (&surface->base);
bounded = _cairo_surface_get_extents (target, extents);
cairo_surface_destroy (target);
return bounded;
}
static const cairo_surface_backend_t _cairo_surface_snapshot_backend = {
CAIRO_INTERNAL_SURFACE_TYPE_SNAPSHOT,
_cairo_surface_snapshot_finish,
NULL,
NULL, /* create similar */
NULL, /* create similar image */
NULL, /* map to image */
NULL, /* unmap image */
_cairo_surface_snapshot_source,
_cairo_surface_snapshot_acquire_source_image,
_cairo_surface_snapshot_release_source_image,
NULL, /* snapshot */
NULL, /* copy_page */
NULL, /* show_page */
_cairo_surface_snapshot_get_extents,
NULL, /* get-font-options */
_cairo_surface_snapshot_flush,
};
static void
_cairo_surface_snapshot_copy_on_write (cairo_surface_t *surface)
{
cairo_surface_snapshot_t *snapshot = (cairo_surface_snapshot_t *) surface;
cairo_image_surface_t *image;
cairo_surface_t *clone;
void *extra;
cairo_status_t status;
TRACE ((stderr, "%s: target=%d\n",
__FUNCTION__, snapshot->target->unique_id));
/* We need to make an image copy of the original surface since the
* snapshot may exceed the lifetime of the original device, i.e.
* when we later need to use the snapshot the data may have already
* been lost.
*/
CAIRO_MUTEX_LOCK (snapshot->mutex);
if (snapshot->target->backend->snapshot != NULL) {
clone = snapshot->target->backend->snapshot (snapshot->target);
if (clone != NULL) {
assert (clone->status || ! _cairo_surface_is_snapshot (clone));
goto done;
}
}
/* XXX copy to a similar surface, leave acquisition till later?
* We should probably leave such decisions to the backend in case we
* rely upon devices/connections like Xlib.
*/
status = _cairo_surface_acquire_source_image (snapshot->target, &image, &extra);
if (unlikely (status)) {
snapshot->target = _cairo_surface_create_in_error (status);
status = _cairo_surface_set_error (surface, status);
goto unlock;
}
clone = image->base.backend->snapshot (&image->base);
_cairo_surface_release_source_image (snapshot->target, image, extra);
done:
status = _cairo_surface_set_error (surface, clone->status);
snapshot->target = snapshot->clone = clone;
snapshot->base.type = clone->type;
unlock:
CAIRO_MUTEX_UNLOCK (snapshot->mutex);
}
/**
* _cairo_surface_snapshot:
* @surface: a #cairo_surface_t
*
* Make an immutable reference to @surface. It is an error to call a
* surface-modifying function on the result of this function. The
* resulting 'snapshot' is a lazily copied-on-write surface i.e. it
* remains a reference to the original surface until that surface is
* written to again, at which time a copy is made of the original surface
* and the snapshot then points to that instead. Multiple snapshots of the
* same unmodified surface point to the same copy.
*
* The caller owns the return value and should call
* cairo_surface_destroy() when finished with it. This function will not
* return %NULL, but will return a nil surface instead.
*
* Return value: The snapshot surface. Note that the return surface
* may not necessarily be of the same type as @surface.
**/
cairo_surface_t *
_cairo_surface_snapshot (cairo_surface_t *surface)
{
cairo_surface_snapshot_t *snapshot;
cairo_status_t status;
TRACE ((stderr, "%s: target=%d\n", __FUNCTION__, surface->unique_id));
if (unlikely (surface->status))
return _cairo_surface_create_in_error (surface->status);
if (unlikely (surface->finished))
return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_SURFACE_FINISHED));
if (surface->snapshot_of != NULL)
return cairo_surface_reference (surface);
if (_cairo_surface_is_snapshot (surface))
return cairo_surface_reference (surface);
snapshot = (cairo_surface_snapshot_t *)
_cairo_surface_has_snapshot (surface, &_cairo_surface_snapshot_backend);
if (snapshot != NULL)
return cairo_surface_reference (&snapshot->base);
snapshot = malloc (sizeof (cairo_surface_snapshot_t));
if (unlikely (snapshot == NULL))
return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_SURFACE_FINISHED));
_cairo_surface_init (&snapshot->base,
&_cairo_surface_snapshot_backend,
NULL, /* device */
surface->content,
surface->is_vector);
snapshot->base.type = surface->type;
CAIRO_MUTEX_INIT (snapshot->mutex);
snapshot->target = surface;
snapshot->clone = NULL;
status = _cairo_surface_copy_mime_data (&snapshot->base, surface);
if (unlikely (status)) {
cairo_surface_destroy (&snapshot->base);
return _cairo_surface_create_in_error (status);
}
snapshot->base.device_transform = surface->device_transform;
snapshot->base.device_transform_inverse = surface->device_transform_inverse;
_cairo_surface_attach_snapshot (surface,
&snapshot->base,
_cairo_surface_snapshot_copy_on_write);
return &snapshot->base;
}