| /* 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 "ginitable.h" |
| #include "glibintl.h" |
| |
| |
| /** |
| * SECTION:ginitable |
| * @short_description: Failable object initialization interface |
| * @include: gio/gio.h |
| * @see_also: #GAsyncInitable |
| * |
| * #GInitable is implemented by objects that can fail during |
| * initialization. If an object implements this interface then |
| * it must be initialized as the first thing after construction, |
| * either via g_initable_init() or g_async_initable_init_async() |
| * (the latter is only available if it also implements #GAsyncInitable). |
| * |
| * 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. |
| * |
| * 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_initable_new() directly, or indirectly via a foo_thing_new() wrapper. |
| * This will call g_initable_init() under the cover, returning %NULL and |
| * setting a #GError on failure (at which point the instance is |
| * unreferenced). |
| * |
| * For bindings in languages where the native constructor supports |
| * exceptions the binding could check for objects implemention %GInitable |
| * during normal construction and automatically initialize them, throwing |
| * an exception on failure. |
| */ |
| |
| typedef GInitableIface GInitableInterface; |
| G_DEFINE_INTERFACE (GInitable, g_initable, G_TYPE_OBJECT) |
| |
| static void |
| g_initable_default_init (GInitableInterface *iface) |
| { |
| } |
| |
| /** |
| * g_initable_init: |
| * @initable: a #GInitable. |
| * @cancellable: optional #GCancellable object, %NULL to ignore. |
| * @error: a #GError location to store the error occurring, or %NULL to |
| * ignore. |
| * |
| * Initializes the object implementing the interface. |
| * |
| * This method is intended for language bindings. If writing in C, |
| * g_initable_new() should typically be used instead. |
| * |
| * The object must be initialized before any real use after initial |
| * construction, either with this function or g_async_initable_init_async(). |
| * |
| * 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 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. See the [introduction][ginitable] for more details. |
| * |
| * Callers should not assume that a class which implements #GInitable can be |
| * initialized multiple times, unless the class explicitly documents itself as |
| * supporting this. Generally, a class’ implementation of init() can assume |
| * (and assert) that it will only be called once. Previously, this documentation |
| * recommended all #GInitable implementations should be idempotent; that |
| * recommendation was relaxed in GLib 2.54. |
| * |
| * If a class explicitly supports being initialized multiple times, it is |
| * recommended that the method is idempotent: multiple calls with the same |
| * arguments should return the same results. Only the first call initializes |
| * the object; further calls return the result of the first call. |
| * |
| * One reason why a class might need to support idempotent initialization is if |
| * it is designed to be used via the singleton pattern, with a |
| * #GObjectClass.constructor that sometimes returns an existing instance. |
| * In this pattern, a caller would expect to be able to call g_initable_init() |
| * on the result of g_object_new(), regardless of whether it is in fact a new |
| * instance. |
| * |
| * 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_initable_init (GInitable *initable, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GInitableIface *iface; |
| |
| g_return_val_if_fail (G_IS_INITABLE (initable), FALSE); |
| |
| iface = G_INITABLE_GET_IFACE (initable); |
| |
| return (* iface->init) (initable, cancellable, error); |
| } |
| |
| /** |
| * g_initable_new: |
| * @object_type: a #GType supporting #GInitable. |
| * @cancellable: optional #GCancellable object, %NULL to ignore. |
| * @error: a #GError location to store the error occurring, or %NULL to |
| * ignore. |
| * @first_property_name: (nullable): 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 #GInitable object. This is |
| * similar to g_object_new() but also initializes the object |
| * and returns %NULL, setting an error on failure. |
| * |
| * Returns: (type GObject.Object) (transfer full): a newly allocated |
| * #GObject, or %NULL on error |
| * |
| * Since: 2.22 |
| */ |
| gpointer |
| g_initable_new (GType object_type, |
| GCancellable *cancellable, |
| GError **error, |
| const gchar *first_property_name, |
| ...) |
| { |
| GObject *object; |
| va_list var_args; |
| |
| va_start (var_args, first_property_name); |
| object = g_initable_new_valist (object_type, |
| first_property_name, var_args, |
| cancellable, error); |
| va_end (var_args); |
| |
| return object; |
| } |
| |
| /** |
| * g_initable_newv: |
| * @object_type: a #GType supporting #GInitable. |
| * @n_parameters: the number of parameters in @parameters |
| * @parameters: (array length=n_parameters): the parameters to use to construct the object |
| * @cancellable: optional #GCancellable object, %NULL to ignore. |
| * @error: a #GError location to store the error occurring, or %NULL to |
| * ignore. |
| * |
| * Helper function for constructing #GInitable object. This is |
| * similar to g_object_newv() but also initializes the object |
| * and returns %NULL, setting an error on failure. |
| * |
| * Returns: (type GObject.Object) (transfer full): a newly allocated |
| * #GObject, or %NULL on error |
| * |
| * Since: 2.22 |
| * Deprecated: 2.54: Use g_object_new_with_properties() and |
| * g_initable_init() instead. See #GParameter for more information. |
| */ |
| gpointer |
| g_initable_newv (GType object_type, |
| guint n_parameters, |
| GParameter *parameters, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GObject *obj; |
| |
| g_return_val_if_fail (G_TYPE_IS_INITABLE (object_type), NULL); |
| |
| G_GNUC_BEGIN_IGNORE_DEPRECATIONS |
| obj = g_object_newv (object_type, n_parameters, parameters); |
| G_GNUC_END_IGNORE_DEPRECATIONS |
| |
| if (!g_initable_init (G_INITABLE (obj), cancellable, error)) |
| { |
| g_object_unref (obj); |
| return NULL; |
| } |
| |
| return (gpointer)obj; |
| } |
| |
| /** |
| * g_initable_new_valist: |
| * @object_type: a #GType supporting #GInitable. |
| * @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. |
| * @cancellable: optional #GCancellable object, %NULL to ignore. |
| * @error: a #GError location to store the error occurring, or %NULL to |
| * ignore. |
| * |
| * Helper function for constructing #GInitable object. This is |
| * similar to g_object_new_valist() but also initializes the object |
| * and returns %NULL, setting an error on failure. |
| * |
| * Returns: (type GObject.Object) (transfer full): a newly allocated |
| * #GObject, or %NULL on error |
| * |
| * Since: 2.22 |
| */ |
| GObject* |
| g_initable_new_valist (GType object_type, |
| const gchar *first_property_name, |
| va_list var_args, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GObject *obj; |
| |
| g_return_val_if_fail (G_TYPE_IS_INITABLE (object_type), NULL); |
| |
| obj = g_object_new_valist (object_type, |
| first_property_name, |
| var_args); |
| |
| if (!g_initable_init (G_INITABLE (obj), cancellable, error)) |
| { |
| g_object_unref (obj); |
| return NULL; |
| } |
| |
| return obj; |
| } |