| /* 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 2.1 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, see <http://www.gnu.org/licenses/>. |
| * |
| * Author: Alexander Larsson <alexl@redhat.com> |
| */ |
| |
| #include "config.h" |
| #include "gasyncinitable.h" |
| #include "gasyncresult.h" |
| #include "gsimpleasyncresult.h" |
| #include "gtask.h" |
| #include "glibintl.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. |
| * |
| * A typical implementation might look something like this: |
| * |
| * |[<!-- language="C" --> |
| * enum { |
| * NOT_INITIALIZED, |
| * INITIALIZING, |
| * INITIALIZED |
| * }; |
| * |
| * static void |
| * _foo_ready_cb (Foo *self) |
| * { |
| * GList *l; |
| * |
| * self->priv->state = INITIALIZED; |
| * |
| * for (l = self->priv->init_results; l != NULL; l = l->next) |
| * { |
| * GTask *task = l->data; |
| * |
| * if (self->priv->success) |
| * g_task_return_boolean (task, TRUE); |
| * else |
| * g_task_return_new_error (task, ...); |
| * g_object_unref (task); |
| * } |
| * |
| * g_list_free (self->priv->init_results); |
| * self->priv->init_results = NULL; |
| * } |
| * |
| * static void |
| * foo_init_async (GAsyncInitable *initable, |
| * int io_priority, |
| * GCancellable *cancellable, |
| * GAsyncReadyCallback callback, |
| * gpointer user_data) |
| * { |
| * Foo *self = FOO (initable); |
| * GTask *task; |
| * |
| * task = g_task_new (initable, cancellable, callback, user_data); |
| * g_task_set_name (task, G_STRFUNC); |
| * |
| * switch (self->priv->state) |
| * { |
| * case NOT_INITIALIZED: |
| * _foo_get_ready (self); |
| * self->priv->init_results = g_list_append (self->priv->init_results, |
| * task); |
| * self->priv->state = INITIALIZING; |
| * break; |
| * case INITIALIZING: |
| * self->priv->init_results = g_list_append (self->priv->init_results, |
| * task); |
| * break; |
| * case INITIALIZED: |
| * if (!self->priv->success) |
| * g_task_return_new_error (task, ...); |
| * else |
| * g_task_return_boolean (task, TRUE); |
| * g_object_unref (task); |
| * break; |
| * } |
| * } |
| * |
| * static gboolean |
| * foo_init_finish (GAsyncInitable *initable, |
| * GAsyncResult *result, |
| * GError **error) |
| * { |
| * g_return_val_if_fail (g_task_is_valid (result, initable), FALSE); |
| * |
| * return g_task_propagate_boolean (G_TASK (result), error); |
| * } |
| * |
| * static void |
| * foo_async_initable_iface_init (gpointer g_iface, |
| * gpointer data) |
| * { |
| * GAsyncInitableIface *iface = g_iface; |
| * |
| * iface->init_async = foo_init_async; |
| * iface->init_finish = foo_init_finish; |
| * } |
| * ]| |
| */ |
| |
| 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); |
| |
| |
| typedef GAsyncInitableIface GAsyncInitableInterface; |
| G_DEFINE_INTERFACE (GAsyncInitable, g_async_initable, G_TYPE_OBJECT) |
| |
| |
| static void |
| g_async_initable_default_init (GAsyncInitableInterface *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 [I/O priority][io-priority] 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. |
| * |
| * This method is intended for language bindings. If writing in C, |
| * g_async_initable_new_async() should typically be used 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. |
| * |
| * As with #GInitable, if the object is not initialized, or initialization |
| * returns with an error, then all operations on the object except |
| * g_object_ref() and g_object_unref() are considered to be invalid, and |
| * have undefined behaviour. They will often fail with g_critical() or |
| * g_warning(), but this must not be relied on. |
| * |
| * Callers should not assume that a class which implements #GAsyncInitable can |
| * be initialized multiple times; for more information, see g_initable_init(). |
| * If a class explicitly supports being initialized multiple times, |
| * implementation requires yielding all subsequent calls to init_async() on the |
| * results of the first call. |
| * |
| * 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 occurring, 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_async_result_legacy_propagate_error (res, error)) |
| return FALSE; |
| |
| iface = G_ASYNC_INITABLE_GET_IFACE (initable); |
| |
| return (* iface->init_finish) (initable, res, error); |
| } |
| |
| static void |
| async_init_thread (GTask *task, |
| gpointer source_object, |
| gpointer task_data, |
| GCancellable *cancellable) |
| { |
| GError *error = NULL; |
| |
| if (g_initable_init (G_INITABLE (source_object), cancellable, &error)) |
| g_task_return_boolean (task, TRUE); |
| else |
| g_task_return_error (task, error); |
| } |
| |
| static void |
| g_async_initable_real_init_async (GAsyncInitable *initable, |
| int io_priority, |
| GCancellable *cancellable, |
| GAsyncReadyCallback callback, |
| gpointer user_data) |
| { |
| GTask *task; |
| |
| g_return_if_fail (G_IS_INITABLE (initable)); |
| |
| task = g_task_new (initable, cancellable, callback, user_data); |
| g_task_set_source_tag (task, g_async_initable_real_init_async); |
| g_task_set_priority (task, io_priority); |
| g_task_run_in_thread (task, async_init_thread); |
| g_object_unref (task); |
| } |
| |
| static gboolean |
| g_async_initable_real_init_finish (GAsyncInitable *initable, |
| GAsyncResult *res, |
| GError **error) |
| { |
| /* For backward compatibility we have to process GSimpleAsyncResults |
| * even though g_async_initable_real_init_async doesn't generate |
| * them any more. |
| */ |
| G_GNUC_BEGIN_IGNORE_DEPRECATIONS |
| 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; |
| else |
| return TRUE; |
| } |
| G_GNUC_END_IGNORE_DEPRECATIONS |
| |
| g_return_val_if_fail (g_task_is_valid (res, initable), FALSE); |
| |
| return g_task_propagate_boolean (G_TASK (res), error); |
| } |
| |
| /** |
| * g_async_initable_new_async: |
| * @object_type: a #GType supporting #GAsyncInitable. |
| * @io_priority: the [I/O priority][io-priority] 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: (nullable): the name of the first property, or %NULL if no |
| * properties |
| * @...: the value of the first property, followed by other property |
| * value pairs, and ended by %NULL. |
| * |
| * Helper function for constructing #GAsyncInitable object. This is |
| * similar to g_object_new() but also initializes the object asynchronously. |
| * |
| * When the initialization is finished, @callback will be called. You can |
| * then call g_async_initable_new_finish() to get the 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 [I/O priority][io-priority] 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 #GAsyncInitable object. This is |
| * similar to g_object_newv() but also initializes the object asynchronously. |
| * |
| * When the initialization is finished, @callback will be called. You can |
| * then call g_async_initable_new_finish() to get the new object and check |
| * for any errors. |
| * |
| * Since: 2.22 |
| * Deprecated: 2.54: Use g_object_new_with_properties() and |
| * g_async_initable_init_async() instead. See #GParameter for more information. |
| */ |
| G_GNUC_BEGIN_IGNORE_DEPRECATIONS |
| 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_object_unref (obj); /* Passed ownership to async call */ |
| } |
| G_GNUC_END_IGNORE_DEPRECATIONS |
| |
| /** |
| * 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 [I/O priority][io-priority] 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 #GAsyncInitable object. This is |
| * similar to g_object_new_valist() but also initializes the object |
| * asynchronously. |
| * |
| * When the initialization is finished, @callback will be called. You can |
| * then call g_async_initable_new_finish() to get the 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: return location for errors, 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: (type GObject.Object) (transfer full): 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 (G_OBJECT (initable)); |
| else |
| return NULL; |
| } |