/* Cairo - a vector graphics library with display and print output
*
* 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 Intel Corporation.
*
* Contributors(s):
* Chris Wilson <chris@chris-wilson.co.uk>
*/
#include "cairoint.h"
#include "cairo-device-private.h"
#include "cairo-error-private.h"
/**
* SECTION:cairo-device
* @Title: cairo_device_t
* @Short_Description: interface to underlying rendering system
* @See_Also: #cairo_surface_t
*
* Devices are the abstraction Cairo employs for the rendering system
* used by a #cairo_surface_t. You can get the device of a surface using
* cairo_surface_get_device().
*
* Devices are created using custom functions specific to the rendering
* system you want to use. See the documentation for the surface types
* for those functions.
*
* An important function that devices fulfill is sharing access to the
* rendering system between Cairo and your application. If you want to
* access a device directly that you used to draw to with Cairo, you must
* first call cairo_device_flush() to ensure that Cairo finishes all
* operations on the device and resets it to a clean state.
*
* Cairo also provides the functions cairo_device_acquire() and
* cairo_device_release() to synchronize access to the rendering system
* in a multithreaded environment. This is done internally, but can also
* be used by applications.
*
* Putting this all together, a function that works with devices should
* look something like this:
* <informalexample><programlisting>
* void
* my_device_modifying_function (cairo_device_t *device)
* {
* cairo_status_t status;
*
* // Ensure the device is properly reset
* cairo_device_flush (device);
* // Try to acquire the device
* status = cairo_device_acquire (device);
* if (status != CAIRO_STATUS_SUCCESS) {
* printf ("Failed to acquire the device: %s\n", cairo_status_to_string (status));
* return;
* }
*
* // Do the custom operations on the device here.
* // But do not call any Cairo functions that might acquire devices.
*
* // Release the device when done.
* cairo_device_release (device);
* }
* </programlisting></informalexample>
*
* <note><para>Please refer to the documentation of each backend for
* additional usage requirements, guarantees provided, and
* interactions with existing surface API of the device functions for
* surfaces of that type.
* </para></note>
**/
static const cairo_device_t _nil_device = {
CAIRO_REFERENCE_COUNT_INVALID,
CAIRO_STATUS_NO_MEMORY,
};
static const cairo_device_t _mismatch_device = {
CAIRO_REFERENCE_COUNT_INVALID,
CAIRO_STATUS_DEVICE_TYPE_MISMATCH,
};
static const cairo_device_t _invalid_device = {
CAIRO_REFERENCE_COUNT_INVALID,
CAIRO_STATUS_DEVICE_ERROR,
};
cairo_device_t *
_cairo_device_create_in_error (cairo_status_t status)
{
switch (status) {
case CAIRO_STATUS_NO_MEMORY:
return (cairo_device_t *) &_nil_device;
case CAIRO_STATUS_DEVICE_ERROR:
return (cairo_device_t *) &_invalid_device;
case CAIRO_STATUS_DEVICE_TYPE_MISMATCH:
return (cairo_device_t *) &_mismatch_device;
case CAIRO_STATUS_SUCCESS:
case CAIRO_STATUS_LAST_STATUS:
ASSERT_NOT_REACHED;
/* fall-through */
case CAIRO_STATUS_SURFACE_TYPE_MISMATCH:
case CAIRO_STATUS_INVALID_STATUS:
case CAIRO_STATUS_INVALID_FORMAT:
case CAIRO_STATUS_INVALID_VISUAL:
case CAIRO_STATUS_READ_ERROR:
case CAIRO_STATUS_WRITE_ERROR:
case CAIRO_STATUS_FILE_NOT_FOUND:
case CAIRO_STATUS_TEMP_FILE_ERROR:
case CAIRO_STATUS_INVALID_STRIDE:
case CAIRO_STATUS_INVALID_SIZE:
case CAIRO_STATUS_INVALID_RESTORE:
case CAIRO_STATUS_INVALID_POP_GROUP:
case CAIRO_STATUS_NO_CURRENT_POINT:
case CAIRO_STATUS_INVALID_MATRIX:
case CAIRO_STATUS_NULL_POINTER:
case CAIRO_STATUS_INVALID_STRING:
case CAIRO_STATUS_INVALID_PATH_DATA:
case CAIRO_STATUS_SURFACE_FINISHED:
case CAIRO_STATUS_PATTERN_TYPE_MISMATCH:
case CAIRO_STATUS_INVALID_DASH:
case CAIRO_STATUS_INVALID_DSC_COMMENT:
case CAIRO_STATUS_INVALID_INDEX:
case CAIRO_STATUS_CLIP_NOT_REPRESENTABLE:
case CAIRO_STATUS_FONT_TYPE_MISMATCH:
case CAIRO_STATUS_USER_FONT_IMMUTABLE:
case CAIRO_STATUS_USER_FONT_ERROR:
case CAIRO_STATUS_NEGATIVE_COUNT:
case CAIRO_STATUS_INVALID_CLUSTERS:
case CAIRO_STATUS_INVALID_SLANT:
case CAIRO_STATUS_INVALID_WEIGHT:
case CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED:
case CAIRO_STATUS_INVALID_CONTENT:
case CAIRO_STATUS_INVALID_MESH_CONSTRUCTION:
case CAIRO_STATUS_DEVICE_FINISHED:
default:
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
return (cairo_device_t *) &_nil_device;
}
}
void
_cairo_device_init (cairo_device_t *device,
const cairo_device_backend_t *backend)
{
CAIRO_REFERENCE_COUNT_INIT (&device->ref_count, 1);
device->status = CAIRO_STATUS_SUCCESS;
device->backend = backend;
CAIRO_RECURSIVE_MUTEX_INIT (device->mutex);
device->mutex_depth = 0;
device->finished = FALSE;
_cairo_user_data_array_init (&device->user_data);
}
/**
* cairo_device_reference:
* @device: a #cairo_device_t
*
* Increases the reference count on @device by one. This prevents
* @device from being destroyed until a matching call to
* cairo_device_destroy() is made.
*
* The number of references to a #cairo_device_t can be get using
* cairo_device_get_reference_count().
*
* Return value: the referenced #cairo_device_t.
*
* Since: 1.10
**/
cairo_device_t *
cairo_device_reference (cairo_device_t *device)
{
if (device == NULL ||
CAIRO_REFERENCE_COUNT_IS_INVALID (&device->ref_count))
{
return device;
}
assert (CAIRO_REFERENCE_COUNT_HAS_REFERENCE
(&device
->ref_count
)); _cairo_reference_count_inc (&device->ref_count);
return device;
}
slim_hidden_def (cairo_device_reference);
/**
* cairo_device_status:
* @device: a #cairo_device_t
*
* Checks whether an error has previously occurred for this
* device.
*
* Return value: %CAIRO_STATUS_SUCCESS on success or an error code if
* the device is in an error state.
*
* Since: 1.10
**/
cairo_status_t
cairo_device_status (cairo_device_t *device)
{
if (device == NULL)
return CAIRO_STATUS_NULL_POINTER;
return device->status;
}
/**
* cairo_device_flush:
* @device: a #cairo_device_t
*
* Finish any pending operations for the device and also restore any
* temporary modifications cairo has made to the device's state.
* This function must be called before switching from using the
* device with Cairo to operating on it directly with native APIs.
* If the device doesn't support direct access, then this function
* does nothing.
*
* This function may acquire devices.
*
* Since: 1.10
**/
void
cairo_device_flush (cairo_device_t *device)
{
cairo_status_t status;
if (device == NULL || device->status)
return;
if (device->finished)
return;
if (device->backend->flush != NULL) {
status = device->backend->flush (device);
if (unlikely (status))
status = _cairo_device_set_error (device, status);
}
}
slim_hidden_def (cairo_device_flush);
/**
* cairo_device_finish:
* @device: the #cairo_device_t to finish
*
* This function finishes the device and drops all references to
* external resources. All surfaces, fonts and other objects created
* for this @device will be finished, too.
* Further operations on the @device will not affect the @device but
* will instead trigger a %CAIRO_STATUS_DEVICE_FINISHED error.
*
* When the last call to cairo_device_destroy() decreases the
* reference count to zero, cairo will call cairo_device_finish() if
* it hasn't been called already, before freeing the resources
* associated with the device.
*
* This function may acquire devices.
*
* Since: 1.10
**/
void
cairo_device_finish (cairo_device_t *device)
{
if (device == NULL ||
CAIRO_REFERENCE_COUNT_IS_INVALID (&device->ref_count))
{
return;
}
if (device->finished)
return;
cairo_device_flush (device);
if (device->backend->finish != NULL)
device->backend->finish (device);
/* We only finish the device after the backend's callback returns because
* the device might still be needed during the callback
* (e.g. for cairo_device_acquire ()).
*/
device->finished = TRUE;
}
slim_hidden_def (cairo_device_finish);
/**
* cairo_device_destroy:
* @device: a #cairo_device_t
*
* Decreases the reference count on @device by one. If the result is
* zero, then @device and all associated resources are freed. See
* cairo_device_reference().
*
* This function may acquire devices if the last reference was dropped.
*
* Since: 1.10
**/
void
cairo_device_destroy (cairo_device_t *device)
{
cairo_user_data_array_t user_data;
if (device == NULL ||
CAIRO_REFERENCE_COUNT_IS_INVALID (&device->ref_count))
{
return;
}
assert (CAIRO_REFERENCE_COUNT_HAS_REFERENCE
(&device
->ref_count
)); if (! _cairo_reference_count_dec_and_test (&device->ref_count))
return;
cairo_device_finish (device);
assert (device
->mutex_depth
== 0); CAIRO_MUTEX_FINI (device->mutex);
user_data = device->user_data;
device->backend->destroy (device);
_cairo_user_data_array_fini (&user_data);
}
slim_hidden_def (cairo_device_destroy);
/**
* cairo_device_get_type:
* @device: a #cairo_device_t
*
* This function returns the type of the device. See #cairo_device_type_t
* for available types.
*
* Return value: The type of @device.
*
* Since: 1.10
**/
cairo_device_type_t
cairo_device_get_type (cairo_device_t *device)
{
if (device == NULL ||
CAIRO_REFERENCE_COUNT_IS_INVALID (&device->ref_count))
{
return CAIRO_DEVICE_TYPE_INVALID;
}
return device->backend->type;
}
/**
* cairo_device_acquire:
* @device: a #cairo_device_t
*
* Acquires the @device for the current thread. This function will block
* until no other thread has acquired the device.
*
* If the return value is %CAIRO_STATUS_SUCCESS, you successfully acquired the
* device. From now on your thread owns the device and no other thread will be
* able to acquire it until a matching call to cairo_device_release(). It is
* allowed to recursively acquire the device multiple times from the same
* thread.
*
* <note><para>You must never acquire two different devices at the same time
* unless this is explicitly allowed. Otherwise the possibility of deadlocks
* exist.
*
* As various Cairo functions can acquire devices when called, these functions
* may also cause deadlocks when you call them with an acquired device. So you
* must not have a device acquired when calling them. These functions are
* marked in the documentation.
* </para></note>
*
* Return value: %CAIRO_STATUS_SUCCESS on success or an error code if
* the device is in an error state and could not be
* acquired. After a successful call to cairo_device_acquire(),
* a matching call to cairo_device_release() is required.
*
* Since: 1.10
**/
cairo_status_t
cairo_device_acquire (cairo_device_t *device)
{
if (device == NULL)
return CAIRO_STATUS_SUCCESS;
if (unlikely (device->status))
return device->status;
if (unlikely (device->finished))
return _cairo_device_set_error (device, CAIRO_STATUS_DEVICE_FINISHED);
CAIRO_MUTEX_LOCK (device->mutex);
if (device->mutex_depth++ == 0) {
if (device->backend->lock != NULL)
device->backend->lock (device);
}
return CAIRO_STATUS_SUCCESS;
}
slim_hidden_def (cairo_device_acquire);
/**
* cairo_device_release:
* @device: a #cairo_device_t
*
* Releases a @device previously acquired using cairo_device_acquire(). See
* that function for details.
*
* Since: 1.10
**/
void
cairo_device_release (cairo_device_t *device)
{
if (device == NULL)
return;
assert (device
->mutex_depth
> 0);
if (--device->mutex_depth == 0) {
if (device->backend->unlock != NULL)
device->backend->unlock (device);
}
CAIRO_MUTEX_UNLOCK (device->mutex);
}
slim_hidden_def (cairo_device_release);
cairo_status_t
_cairo_device_set_error (cairo_device_t *device,
cairo_status_t status)
{
if (status == CAIRO_STATUS_SUCCESS)
return CAIRO_STATUS_SUCCESS;
_cairo_status_set_error (&device->status, status);
return _cairo_error (status);
}
/**
* cairo_device_get_reference_count:
* @device: a #cairo_device_t
*
* Returns the current reference count of @device.
*
* Return value: the current reference count of @device. If the
* object is a nil object, 0 will be returned.
*
* Since: 1.10
**/
unsigned int
cairo_device_get_reference_count (cairo_device_t *device)
{
if (device == NULL ||
CAIRO_REFERENCE_COUNT_IS_INVALID (&device->ref_count))
return 0;
return CAIRO_REFERENCE_COUNT_GET_VALUE (&device->ref_count);
}
/**
* cairo_device_get_user_data:
* @device: a #cairo_device_t
* @key: the address of the #cairo_user_data_key_t the user data was
* attached to
*
* Return user data previously attached to @device using the
* specified key. If no user data has been attached with the given
* key this function returns %NULL.
*
* Return value: the user data previously attached or %NULL.
*
* Since: 1.10
**/
void *
cairo_device_get_user_data (cairo_device_t *device,
const cairo_user_data_key_t *key)
{
return _cairo_user_data_array_get_data (&device->user_data,
key);
}
/**
* cairo_device_set_user_data:
* @device: a #cairo_device_t
* @key: the address of a #cairo_user_data_key_t to attach the user data to
* @user_data: the user data to attach to the #cairo_device_t
* @destroy: a #cairo_destroy_func_t which will be called when the
* #cairo_t is destroyed or when new user data is attached using the
* same key.
*
* Attach user data to @device. To remove user data from a surface,
* call this function with the key that was used to set it and %NULL
* for @data.
*
* Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY if a
* slot could not be allocated for the user data.
*
* Since: 1.10
**/
cairo_status_t
cairo_device_set_user_data (cairo_device_t *device,
const cairo_user_data_key_t *key,
void *user_data,
cairo_destroy_func_t destroy)
{
if (CAIRO_REFERENCE_COUNT_IS_INVALID (&device->ref_count))
return device->status;
return _cairo_user_data_array_set_data (&device->user_data,
key, user_data, destroy);
}