/* GIO - GLib Input, Output and Streaming Library
*
* Copyright (C) 2009 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General
* Public License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*
* Author: Alexander Larsson <alexl@redhat.com>
*/
#include "config.h"
#include "gasyncinitable.h"
#include "gasyncresult.h"
#include "gsimpleasyncresult.h"
#include "glibintl.h"
#include "gioalias.h"
/**
* SECTION:gasyncinitable
* @short_description: Asynchronously failable object initialization interface
* @include: gio/gio.h
* @see_also: #GInitable
*
* This is the asynchronous version of #GInitable, it behaves the same
* in all ways except that initialization is asynchronous. For more details
* see the descriptions on #GInitable.
*
* A class may implement both the #GInitable and #GAsyncInitable interfaces.
*
* Users of objects implementing this are not intended to use the interface
* method directly, instead it will be used automatically in various ways.
* For C applications you generally just call g_async_initable_new_async()
* directly, or indirectly via a foo_thing_new_async() wrapper. This will call
* g_async_initable_init_async() under the cover, calling back with %NULL and
* a set %GError on failure.
*/
static void g_async_initable_base_init (gpointer g_iface);
static void g_async_initable_real_init_async (GAsyncInitable *initable,
int io_priority,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data);
static gboolean g_async_initable_real_init_finish (GAsyncInitable *initable,
GAsyncResult *res,
GError **error);
GType
g_async_initable_get_type (void)
{
static volatile gsize g_define_type_id__volatile = 0;
if (g_once_init_enter (&g_define_type_id__volatile))
{
const GTypeInfo initable_info =
{
sizeof (GAsyncInitableIface), /* class_size */
g_async_initable_base_init, /* base_init */
NULL, /* base_finalize */
NULL,
NULL, /* class_finalize */
NULL, /* class_data */
0,
0, /* n_preallocs */
NULL
};
GType g_define_type_id =
g_type_register_static (G_TYPE_INTERFACE, I_("GAsyncInitable"),
&initable_info, 0);
g_type_interface_add_prerequisite (g_define_type_id, G_TYPE_OBJECT);
g_once_init_leave (&g_define_type_id__volatile, g_define_type_id);
}
return g_define_type_id__volatile;
}
static void
g_async_initable_base_init (gpointer g_iface)
{
GAsyncInitableIface *iface = g_iface;
iface->init_async = g_async_initable_real_init_async;
iface->init_finish = g_async_initable_real_init_finish;
}
/**
* g_async_initable_init_async:
* @initable: a #GAsyncInitable.
* @io_priority: the <link linkend="io-priority">I/O priority</link>
* of the operation.
* @cancellable: optional #GCancellable object, %NULL to ignore.
* @callback: a #GAsyncReadyCallback to call when the request is satisfied
* @user_data: the data to pass to callback function
*
* Starts asynchronous initialization of the object implementing the
* interface. This must be done before any real use of the object after
* initial construction. If the object also implements #GInitable you can
* optionally call g_initable_init() instead.
*
* When the initialization is finished, @callback will be called. You can
* then call g_async_initable_init_finish() to get the result of the
* initialization.
*
* Implementations may also support cancellation. If @cancellable is not
* %NULL, then initialization can be cancelled by triggering the cancellable
* object from another thread. If the operation was cancelled, the error
* %G_IO_ERROR_CANCELLED will be returned. If @cancellable is not %NULL and
* the object doesn't support cancellable initialization the error
* %G_IO_ERROR_NOT_SUPPORTED will be returned.
*
* If this function is not called, or returns with an error then all
* operations on the object should fail, generally returning the
* error %G_IO_ERROR_NOT_INITIALIZED.
*
* Implementations of this method must be idempotent, i.e. multiple calls
* to this function with the same argument should return the same results.
* Only the first call initializes the object, further calls return the result
* of the first call. This is so that its safe to implement the singleton
* pattern in the GObject constructor function.
*
* For classes that also support the #GInitable interface the default
* implementation of this method will run the g_initable_init() function
* in a thread, so if you want to support asynchronous initialization via
* threads, just implement the #GAsyncInitable interface without overriding
* any interface methods.
*
* Since: 2.22
*/
void
g_async_initable_init_async (GAsyncInitable *initable,
int io_priority,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
GAsyncInitableIface *iface;
g_return_if_fail (G_IS_ASYNC_INITABLE (initable));
iface = G_ASYNC_INITABLE_GET_IFACE (initable);
(* iface->init_async) (initable, io_priority, cancellable, callback, user_data);
}
/**
* g_async_initable_init_finish:
* @initable: a #GAsyncInitable.
* @res: a #GAsyncResult.
* @error: a #GError location to store the error occuring, or %NULL to
* ignore.
*
* Finishes asynchronous initialization and returns the result.
* See g_async_initable_init_async().
*
* Returns: %TRUE if successful. If an error has occurred, this function
* will return %FALSE and set @error appropriately if present.
*
* Since: 2.22
*/
gboolean
g_async_initable_init_finish (GAsyncInitable *initable,
GAsyncResult *res,
GError **error)
{
GAsyncInitableIface *iface;
g_return_val_if_fail (G_IS_ASYNC_INITABLE (initable), FALSE);
g_return_val_if_fail (G_IS_ASYNC_RESULT (res), FALSE);
if (G_IS_SIMPLE_ASYNC_RESULT (res))
{
GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (res);
if (g_simple_async_result_propagate_error (simple, error))
return FALSE;
}
iface = G_ASYNC_INITABLE_GET_IFACE (initable);
return (* iface->init_finish) (initable, res, error);
}
static void
async_init_thread (GSimpleAsyncResult *res,
GObject *object,
GCancellable *cancellable)
{
GError *error = NULL;
if (!g_initable_init (G_INITABLE (res), cancellable, &error))
{
g_simple_async_result_set_from_error (res, error);
g_error_free (error);
}
}
static void
g_async_initable_real_init_async (GAsyncInitable *initable,
int io_priority,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
GSimpleAsyncResult *res;
g_return_if_fail (G_IS_INITABLE (initable));
res = g_simple_async_result_new (G_OBJECT (initable), callback, user_data,
g_async_initable_real_init_async);
g_simple_async_result_run_in_thread (res, async_init_thread,
io_priority, cancellable);
g_object_unref (res);
}
static gboolean
g_async_initable_real_init_finish (GAsyncInitable *initable,
GAsyncResult *res,
GError **error)
{
return TRUE; /* Errors handled by base impl */
}
/**
* g_async_initable_new_async:
* @object_type: a #GType supporting #GAsyncInitable.
* @io_priority: the <link linkend="io-priority">I/O priority</link>
* of the operation.
* @cancellable: optional #GCancellable object, %NULL to ignore.
* @callback: a #GAsyncReadyCallback to call when the initialization is
* finished
* @user_data: the data to pass to callback function
* @first_property_name: the name of the first property, or %NULL if no
* properties
* @...: the value if the first property, followed by and other property
* value pairs, and ended by %NULL.
*
* Helper function for constructing #GAsyncInitiable object. This is
* similar to g_object_new() but also initializes the object asyncronously.
*
* When the initialization is finished, @callback will be called. You can
* then call g_async_initable_new_finish() to get new object and check for
* any errors.
*
* Since: 2.22
*/
void
g_async_initable_new_async (GType object_type,
int io_priority,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data,
const gchar *first_property_name,
...)
{
va_list var_args;
va_start (var_args, first_property_name);
g_async_initable_new_valist_async (object_type,
first_property_name, var_args,
io_priority, cancellable,
callback, user_data);
va_end (var_args);
}
/**
* g_async_initable_newv_async:
* @object_type: a #GType supporting #GAsyncInitable.
* @n_parameters: the number of parameters in @parameters
* @parameters: the parameters to use to construct the object
* @io_priority: the <link linkend="io-priority">I/O priority</link>
* of the operation.
* @cancellable: optional #GCancellable object, %NULL to ignore.
* @callback: a #GAsyncReadyCallback to call when the initialization is
* finished
* @user_data: the data to pass to callback function
*
* Helper function for constructing #GAsyncInitiable object. This is
* similar to g_object_newv() but also initializes the object asyncronously.
*
* When the initialization is finished, @callback will be called. You can
* then call g_async_initable_new_finish() to get new object and check for
* any errors.
*
* Since: 2.22
*/
void
g_async_initable_newv_async (GType object_type,
guint n_parameters,
GParameter *parameters,
int io_priority,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
GObject *obj;
g_return_if_fail (G_TYPE_IS_ASYNC_INITABLE (object_type));
obj = g_object_newv (object_type, n_parameters, parameters);
g_async_initable_init_async (G_ASYNC_INITABLE (obj),
io_priority, cancellable,
callback, user_data);
}
/**
* g_async_initable_new_valist_async:
* @object_type: a #GType supporting #GAsyncInitable.
* @first_property_name: the name of the first property, followed by
* the value, and other property value pairs, and ended by %NULL.
* @var_args: The var args list generated from @first_property_name.
* @io_priority: the <link linkend="io-priority">I/O priority</link>
* of the operation.
* @cancellable: optional #GCancellable object, %NULL to ignore.
* @callback: a #GAsyncReadyCallback to call when the initialization is
* finished
* @user_data: the data to pass to callback function
*
* Helper function for constructing #GAsyncInitiable object. This is
* similar to g_object_new_valist() but also initializes the object
* asyncronously.
*
* When the initialization is finished, @callback will be called. You can
* then call g_async_initable_new_finish() to get new object and check for
* any errors.
*
* Since: 2.22
*/
void
g_async_initable_new_valist_async (GType object_type,
const gchar *first_property_name,
va_list var_args,
int io_priority,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
GObject *obj;
g_return_if_fail (G_TYPE_IS_ASYNC_INITABLE (object_type));
obj = g_object_new_valist (object_type,
first_property_name,
var_args);
g_async_initable_init_async (G_ASYNC_INITABLE (obj),
io_priority, cancellable,
callback, user_data);
g_object_unref (obj); /* Passed ownership to async call */
}
/**
* g_async_initable_new_finish:
* @initable: the #GAsyncInitable from the callback
* @res: the #GAsyncResult.from the callback
* @error: a #GError location to store the error occuring, or %NULL to
* ignore.
*
* Finishes the async construction for the various g_async_initable_new calls,
* returning the created object or %NULL on error.
*
* Returns: a newly created #GObject, or %NULL on error. Free with
* g_object_unref().
*
* Since: 2.22
*/
GObject *
g_async_initable_new_finish (GAsyncInitable *initable,
GAsyncResult *res,
GError **error)
{
if (g_async_initable_init_finish (initable, res, error))
return g_object_ref (initable);
else
return NULL;
}
#define __G_ASYNC_INITABLE_C__
#include "gioaliasdef.c"