gio/auto/

initable.rs

// This file was generated by gir (https://github.com/gtk-rs/gir)
// from gir-files (https://github.com/gtk-rs/gir-files)
// DO NOT EDIT

use crate::{ffi, Cancellable};
use glib::{prelude::*, translate::*};

glib::wrapper! {
    /// `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 [`InitableExt::init()`][crate::prelude::InitableExt::init()] or [`AsyncInitableExt::init_async()`][crate::prelude::AsyncInitableExt::init_async()]
    /// (the latter is only available if it also implements [`AsyncInitable`][crate::AsyncInitable]).
    ///
    /// 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 `critical()` or
    /// `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
    /// [`new()`][Self::new()] directly, or indirectly via a `foo_thing_new()` wrapper.
    /// This will call [`InitableExt::init()`][crate::prelude::InitableExt::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 implementing `GInitable`
    /// during normal construction and automatically initialize them, throwing
    /// an exception on failure.
    ///
    /// # Implements
    ///
    /// [`InitableExt`][trait@crate::prelude::InitableExt]
    #[doc(alias = "GInitable")]
    pub struct Initable(Interface<ffi::GInitable, ffi::GInitableIface>);

    match fn {
        type_ => || ffi::g_initable_get_type(),
    }
}

impl Initable {
    pub const NONE: Option<&'static Initable> = None;
}

mod sealed {
    pub trait Sealed {}
    impl<T: super::IsA<super::Initable>> Sealed for T {}
}

/// Trait containing all [`struct@Initable`] methods.
///
/// # Implementors
///
/// [`CharsetConverter`][struct@crate::CharsetConverter], [`DBusConnection`][struct@crate::DBusConnection], [`DBusProxy`][struct@crate::DBusProxy], [`DBusServer`][struct@crate::DBusServer], [`DebugControllerDBus`][struct@crate::DebugControllerDBus], [`DebugController`][struct@crate::DebugController], [`InetAddressMask`][struct@crate::InetAddressMask], [`Initable`][struct@crate::Initable], [`MemoryMonitor`][struct@crate::MemoryMonitor], [`NetworkMonitor`][struct@crate::NetworkMonitor], [`PowerProfileMonitor`][struct@crate::PowerProfileMonitor], [`Socket`][struct@crate::Socket], [`Subprocess`][struct@crate::Subprocess]
pub trait InitableExt: IsA<Initable> + sealed::Sealed + 'static {
    /// 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 [`None`],
    /// then initialization can be cancelled by triggering the cancellable object
    /// from another thread. If the operation was cancelled, the error
    /// [`IOErrorEnum::Cancelled`][crate::IOErrorEnum::Cancelled] will be returned. If @cancellable is not [`None`] and
    /// the object doesn't support cancellable initialization the error
    /// [`IOErrorEnum::NotSupported`][crate::IOErrorEnum::NotSupported] 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.
    /// ## `cancellable`
    /// optional #GCancellable object, [`None`] to ignore.
    ///
    /// # Returns
    ///
    /// [`true`] if successful. If an error has occurred, this function will
    ///     return [`false`] and set @error appropriately if present.
    #[doc(alias = "g_initable_init")]
    unsafe fn init(&self, cancellable: Option<&impl IsA<Cancellable>>) -> Result<(), glib::Error> {
        let mut error = std::ptr::null_mut();
        let is_ok = ffi::g_initable_init(
            self.as_ref().to_glib_none().0,
            cancellable.map(|p| p.as_ref()).to_glib_none().0,
            &mut error,
        );
        debug_assert_eq!(is_ok == glib::ffi::GFALSE, !error.is_null());
        if error.is_null() {
            Ok(())
        } else {
            Err(from_glib_full(error))
        }
    }
}

impl<O: IsA<Initable>> InitableExt for O {}